{"id":98852,"date":"2026-06-12T11:17:37","date_gmt":"2026-06-12T03:17:37","guid":{"rendered":"https:\/\/machinedquartz.com\/guide-trajet-optique-cuves\/"},"modified":"2026-06-12T12:00:42","modified_gmt":"2026-06-12T04:00:42","slug":"guide-trajet-optique-cuves","status":"publish","type":"post","link":"https:\/\/machinedquartz.com\/fr\/guide-trajet-optique-cuves\/","title":{"rendered":"Guide du trajet optique des cuves : comment choisir le bon trajet pour la spectroscopie UV-Vis"},"content":{"rendered":"\n<div class=\"cq-aidef\" style=\"background:#fafbff;border:1px solid #e0e7ff;border-radius:10px;padding:18px 22px;margin:0 0 24px;\"><p style=\"margin:0;font-size:16px;line-height:1.65;color:#1e293b;\"><strong style=\"color:#1a2a6c;\">Le trajet optique d\u2019une cuve, c\u2019est<\/strong> la distance que la lumi\u00e8re parcourt \u00e0 travers l\u2019\u00e9chantillon dans une cuve de spectrophotom\u00e8tre \u2014 la variable L de la loi de Beer-Lambert A = \u03b5 \u00b7 c \u00b7 L. Les cuves standard font 10 mm ; les trajets optiques disponibles vont de 0,01 mm (cuves ultra-minces sub-microlitre) \u00e0 200 mm (analyse de traces \u00e0 long trajet). Doubler le trajet optique double l\u2019absorbance \u00e0 concentration fixe : le choix du trajet est donc le levier de paillasse pour garder les lectures dans la plage lin\u00e9aire 0,1\u20131,0 UA sans diluer l\u2019\u00e9chantillon.<\/p><\/div>\n\n\n\n<style>\n.crc-toolbar { margin: 0 0 36px; }\n.crc-toolbar-header { display:flex; align-items:center; gap:10px; margin:0 0 14px; padding-bottom:10px; border-bottom:2px solid #e8eaf0; }\n.crc-toolbar-header .crc-icon { width:32px; height:32px; background:linear-gradient(135deg,#1a2a6c,#1a73e8); border-radius:8px; display:inline-flex; align-items:center; justify-content:center; color:#fff; font-size:16px; font-weight:700; }\n.crc-toolbar-header h3 { margin:0; font-size:16px; color:#1a2a6c; font-weight:700; letter-spacing:0.3px; }\n.crc-toolbar-header .crc-sub { color:#666; font-size:12px; margin-left:6px; }\n.crc-grid { display:grid; grid-template-columns:repeat(6,1fr); gap:10px; }\n.crc-card { display:block; padding:14px 12px 12px; background:#fff; border:1px solid #e8eaf0; border-radius:10px; text-decoration:none; transition:transform 0.15s ease, box-shadow 0.15s ease, border-color 0.15s ease; position:relative; min-height:96px; }\n.crc-card:hover { transform:translateY(-3px); box-shadow:0 6px 18px rgba(26,42,108,0.12); border-color:#1a73e8; }\n.crc-card-emoji { font-size:24px; line-height:1; display:block; margin-bottom:6px; }\n.crc-card-title { font-size:13px; font-weight:700; color:#1a2a6c; margin:0 0 3px; line-height:1.25; }\n.crc-card-sub { font-size:11px; color:#777; margin:0; line-height:1.35; }\n.crc-card.crc-current { background:linear-gradient(135deg,#1a2a6c 0%,#233a95 100%); border-color:#1a2a6c; cursor:default; pointer-events:none; }\n.crc-card.crc-current .crc-card-title { color:#fff; }\n.crc-card.crc-current .crc-card-sub { color:#b8c8ff; }\n.crc-card.crc-current::after { content:\"YOU ARE HERE\"; position:absolute; top:-7px; right:8px; background:#fbbf24; color:#1a2a6c; font-size:9px; font-weight:800; letter-spacing:0.6px; padding:2px 6px; border-radius:3px; }\n.crc-card.crc-cta { background:linear-gradient(135deg,#059669 0%,#10b981 100%); border-color:#059669; }\n.crc-card.crc-cta .crc-card-title { color:#fff; }\n.crc-card.crc-cta .crc-card-sub { color:#d1fae5; }\n.crc-card.crc-cta:hover { background:linear-gradient(135deg,#047857 0%,#059669 100%); transform:translateY(-3px); box-shadow:0 6px 18px rgba(5,150,105,0.3); border-color:#047857; }\n@media (max-width:980px) { .crc-grid { grid-template-columns:repeat(3,1fr); } }\n@media (max-width:560px) { .crc-grid { grid-template-columns:repeat(2,1fr); } .crc-card { min-height:88px; padding:12px 10px 10px; } .crc-card-emoji { font-size:20px; } .crc-card-title { font-size:12px; } .crc-card-sub { font-size:10.5px; } }\n<\/style>\n<div class=\"crc-toolbar\">\n  <div class=\"crc-toolbar-header\">\n    <span class=\"crc-icon\">\u26a1<\/span>\n    <h3>CENTRE DE RESSOURCES CUVES<\/h3>\n    <span class=\"crc-sub\">\u2014 choisissez un outil pour trouver votre cuve en quelques secondes<\/span>\n  <\/div>\n  <div class=\"crc-grid\">\n    <a href=\"https:\/\/machinedquartz.com\/cuvettes-and-cells-size-chart\/\" class=\"crc-card\">\n  <span class=\"crc-card-emoji\">\ud83d\udcd0<\/span>\n  <p class=\"crc-card-title\">Tableau des tailles<\/p>\n\n  <p class=\"crc-card-sub\">Filtrer 1 300+ par sp\u00e9cification<\/p>\n<\/a>\n    <div class=\"crc-card crc-current\">\n  <span class=\"crc-card-emoji\">\ud83d\udccf<\/span>\n  <p class=\"crc-card-title\">Trajet optique<\/p>\n  <p class=\"crc-card-sub\">guide de 1 mm \u00e0 100 mm<\/p>\n<\/div>\n    <a href=\"https:\/\/machinedquartz.com\/fr\/guide-selection-cuves\/\" class=\"crc-card\">\n  <span class=\"crc-card-emoji\">\ud83c\udfaf<\/span>\n  <p class=\"crc-card-title\">Guide de s\u00e9lection<\/p>\n  <p class=\"crc-card-sub\">Arbre de d\u00e9cision par usage<\/p>\n<\/a>\n    <a href=\"https:\/\/machinedquartz.com\/fr\/compatibilite-solvants-cuves\/\" class=\"crc-card\">\n  <span class=\"crc-card-emoji\">\ud83e\uddea<\/span>\n  <p class=\"crc-card-title\">Compatibilit\u00e9 solvants<\/p>\n  <p class=\"crc-card-sub\">38 solvants \u00d7 3 qualit\u00e9s<\/p>\n<\/a>\n    <a href=\"https:\/\/machinedquartz.com\/fr\/methode-fabrication-cuves\/\" class=\"crc-card\">\n  <span class=\"crc-card-emoji\">\u2699\ufe0f<\/span>\n  <p class=\"crc-card-title\">Glossaire des fabrications<\/p>\n  <p class=\"crc-card-sub\">Std80\/Sint83\/Mold83<\/p>\n<\/a>\n    <a href=\"\/cuvettes-and-cells-custom-fabrication\/\" class=\"crc-card crc-cta\">\n  <span class=\"crc-card-emoji\">\u270f\ufe0f<\/span>\n  <p class=\"crc-card-title\">Besoin de sur-mesure ?<\/p>\n  <p class=\"crc-card-sub\">Un devis en 24 h \u2192<\/p>\n<\/a>\n  <\/div>\n<\/div>\n\n<h2 class=\"csg-h1\" style=\"position:absolute;left:-9999px;width:1px;height:1px;overflow:hidden;\">Guide du trajet optique des cuves : comment choisir le bon trajet pour la spectroscopie UV-Vis<\/h2>\n\n<style>\n.csg-toc-floating { position:fixed; right:24px; top:140px; width:260px; background:#fff; border:1px solid #e8eaf0; border-radius:10px; padding:18px 18px 14px; box-shadow:0 4px 16px rgba(20,30,80,0.08); font-size:12.5px; max-height:70vh; overflow-y:auto; z-index:10; }\n.csg-toc-floating-title { font-size:11px; font-weight:700; letter-spacing:1.5px; color:#233a95; text-transform:uppercase; margin-bottom:10px; padding-bottom:8px; border-bottom:1px solid #eef0f6; }\n.csg-toc-floating ol { list-style:none !important; counter-reset:item; padding:0 !important; margin:0 !important; }\n.csg-toc-floating li { list-style:none !important; counter-increment:item; padding:5px 0 5px 30px !important; margin:0 !important; position:relative; line-height:1.4; }\n.csg-toc-floating li::marker { content:\"\"; }\n.csg-toc-floating li::before { content:counter(item); position:absolute; left:0; top:5px; width:22px; height:22px; background:#eef0f6; border-radius:50%; font-size:10.5px; font-weight:700; color:#666; text-align:center; line-height:22px; }\n.csg-toc-floating li:hover::before { background:#233a95; color:#fff; }\n.csg-toc-floating a { color:#444; text-decoration:none; transition:color 0.15s; display:block; }\n.csg-toc-floating a:hover { color:#233a95; }\n\/* Collapsible TOC \u2014 slides to right edge when closed; highlights active section on scroll *\/\n.csg-toc-floating { transition:transform 0.3s ease, right 0.3s ease, border-radius 0.3s ease, padding 0.3s ease, background 0.3s ease; }\n.csg-toc-floating > summary { cursor:pointer; list-style:none; user-select:none; outline:none; }\n.csg-toc-floating > summary::-webkit-details-marker { display:none; }\n.csg-toc-floating > summary::marker { content:\"\"; }\n.csg-toc-floating[open] > summary::after { content:\"\\25B6\"; float:right; font-size:11px; color:#888; line-height:1.4; margin-left:8px; }\n.csg-toc-floating[open] > ol { animation:csg-toc-slidein 0.25s ease-out; }\n@keyframes csg-toc-slidein { from { opacity:0; transform:translateX(16px); } to { opacity:1; transform:translateX(0); } }\n.csg-toc-floating:not([open]) { right:0 !important; transform:translateX(calc(100% - 36px)); padding:0 !important; border-radius:8px 0 0 8px !important; max-height:none !important; overflow:visible !important; box-shadow:0 4px 16px rgba(20,30,80,0.10) !important; border-color:transparent !important; }\n.csg-toc-floating:not([open]) > summary { writing-mode:vertical-rl; transform:rotate(180deg); padding:20px 10px !important; margin:0 !important; border:none !important; background:linear-gradient(135deg,#1a2a6c 0%,#233a95 100%) !important; color:#fff !important; letter-spacing:1.8px; border-radius:0 8px 8px 0; min-height:140px; text-align:center; font-weight:700; }\n.csg-toc-floating:not([open]) > summary::after { content:\"\\25C0\"; float:none; display:block; margin-top:8px; color:rgba(255,255,255,0.85); transform:rotate(180deg); font-size:13px; }\n.csg-toc-floating:not([open]):hover { transform:translateX(calc(100% - 44px)); }\n.csg-toc-floating li.is-active::before { background:#233a95 !important; color:#fff !important; box-shadow:0 0 0 3px rgba(35,58,149,0.15); }\n.csg-toc-floating li.is-active > a { color:#1a2a6c !important; font-weight:700; }\n.csg-toc-floating li.is-active { background:linear-gradient(90deg, rgba(35,58,149,0.06) 0%, transparent 100%); border-radius:6px; }\n\n@media (max-width:1280px) { .csg-toc-floating { display:none; } }\n<\/style>\n<details class=\"csg-toc-floating\" open>\n  <summary class=\"csg-toc-floating-title\">Sur cette page<\/summary>\n  <ol>\n    <li><a href=\"#what-is\">Qu\u2019est-ce que le trajet optique d\u2019une cuve ?<\/a><\/li>\n    <li><a href=\"#beer-lambert\">La loi de Beer-Lambert expliqu\u00e9e<\/a><\/li>\n    <li><a href=\"#standard-lengths\">Trajets optiques standard & usages<\/a><\/li>\n    <li><a href=\"#how-to-choose\">Comment choisir le bon trajet optique<\/a><\/li>\n    <li><a href=\"#short-path\">Cuves \u00e0 court trajet<\/a><\/li>\n    <li><a href=\"#long-path\">Cuves \u00e0 long trajet<\/a><\/li>\n    <li><a href=\"#z-height\">Trajet optique vs hauteur Z<\/a><\/li>\n    <li><a href=\"#accuracy\">Exactitude & tol\u00e9rance du trajet optique<\/a><\/li>\n    <li><a href=\"#calculator\">Calculateur de trajet optique<\/a><\/li>\n    <li><a href=\"#faq\">FAQ<\/a><\/li>\n  <\/ol>\n<\/details>\n\n<style>\n\/* ===== Path Length Guide \u2014 csg-* system ===== *\/\n.csg-page { max-width:860px; 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}\n  .csg-decision { padding:20px; }\n  .csg-tool-box { flex-direction:column; }\n}\n<\/style>\n\n<div class=\"csg-hero\">\n  <div class=\"csg-hero-inner\">\n    <p class=\"csg-hero-eyebrow\">MachinedQuartz \u00b7 guide de spectroscopie<\/p>\n    <p class=\"csg-hero-h1\">Guide du trajet optique des cuves : comment choisir le bon trajet<\/p>\n    <p class=\"csg-hero-sub\">Le trajet optique est la dimension la plus importante d\u2019une cuve \u2014 il d\u00e9termine la quantit\u00e9 de lumi\u00e8re qui interagit avec votre \u00e9chantillon, contr\u00f4le directement la sensibilit\u00e9 d\u2019absorbance, et fixe la plage de concentration de travail de votre dosage. Ce guide explique la physique, liste chaque trajet optique standard avec son cas d\u2019usage principal, et vous donne un cadre pratique pour choisir.<\/p>\n<div class=\"csg-hero-pills\">\n      <span class=\"csg-hero-pill\">Loi de Beer-Lambert<\/span>\n      <span class=\"csg-hero-pill\">plage 0,1 mm \u2013 200 mm<\/span>\n      <span class=\"csg-hero-pill\">Table de correspondance par application<\/span>\n      <span class=\"csg-hero-pill\">Calculateur interactif<\/span>\n    <\/div>\n    <div class=\"csg-hero-meta\">\n      <span><strong>Derni\u00e8re mise \u00e0 jour :<\/strong> 29 avril 2026<\/span>\n      <span><strong>4 000 mots<\/strong> \u00b7 9 min de lecture<\/span>\n      <span><strong>Pour :<\/strong> spectroscopistes \u00b7 responsables de labo \u00b7 \u00e9tudiants<\/span>\n      <span><strong>Par :<\/strong> \u00c9quipe technique MachinedQuartz \u00b7 depuis 2013<\/span>\n    <\/div>\n  <\/div>\n\n<\/div>\n\n<style>\n.mq-relbar { margin: 24px 0 32px; }\n.mq-relbar-title { font-size:11px; font-weight:700; letter-spacing:1.5px; color:#233a95; text-transform:uppercase; margin-bottom:14px; }\n.mq-relbar-grid { display:grid; gap:10px; }\n.mq-relbar-grid.cols-1 { grid-template-columns:1fr; }\n.mq-relbar-grid.cols-2 { grid-template-columns:repeat(2,1fr); }\n.mq-relbar-grid.cols-3 { grid-template-columns:repeat(3,1fr); }\n.mq-relbar-grid.cols-4 { grid-template-columns:repeat(4,1fr); }\n.mq-relbar-grid.cols-5 { grid-template-columns:repeat(5,1fr); }\n.mq-relbar-grid.cols-6 { grid-template-columns:repeat(3,1fr); }\n.mq-relbar-grid.cols-7 { grid-template-columns:repeat(4,1fr); }\n.mq-relbar-card { display:block; padding:12px 14px; background:#f7f8fc; border:1px solid #e8eaf0; border-radius:8px; text-decoration:none !important; transition:transform 0.15s, box-shadow 0.15s, border-color 0.15s; }\n.mq-relbar-card:hover { transform:translateY(-2px); box-shadow:0 4px 14px rgba(26,42,108,0.10); border-color:#1a73e8; background:#fff; }\n.mq-relbar-card-emoji { font-size:18px; line-height:1; display:inline-block; margin-right:6px; vertical-align:middle; }\n.mq-relbar-card-title { font-size:13px; font-weight:700; color:#1a2a6c !important; margin:0; line-height:1.3; display:inline-block; vertical-align:middle; text-decoration:none !important; }\n.mq-relbar-card-sub { font-size:11px; color:#666 !important; margin:3px 0 0; line-height:1.4; text-decoration:none !important; }\n@media (max-width:1000px) { .mq-relbar-grid.cols-5, .mq-relbar-grid.cols-6, .mq-relbar-grid.cols-7 { grid-template-columns:repeat(3,1fr); } .mq-relbar-grid.cols-4 { grid-template-columns:repeat(2,1fr); } }\n@media (max-width:600px)  { .mq-relbar-grid { grid-template-columns:repeat(2,1fr) !important; } }\n@media (max-width:380px)  { .mq-relbar-grid { grid-template-columns:1fr !important; } }\n<\/style>\n<div class=\"mq-relbar\"><div class=\"mq-relbar-title\">Guides de cuve associ\u00e9s<\/div><div class=\"mq-relbar-grid cols-5\"><a class=\"mq-relbar-card\" href=\"https:\/\/machinedquartz.com\/fr\/cuves-bouchon-vis\/\"><span class=\"mq-relbar-card-emoji\">\ud83d\udd12<\/span><span class=\"mq-relbar-card-title\">Bouchon \u00e0 vis<\/span><p class=\"mq-relbar-card-sub\">Bouchons \u00e9tanches doubl\u00e9s PTFE<\/p><\/a><a class=\"mq-relbar-card\" href=\"https:\/\/machinedquartz.com\/fr\/cuves-demontables\/\"><span class=\"mq-relbar-card-emoji\">\ud83d\udd27<\/span><span class=\"mq-relbar-card-title\">D\u00e9montable<\/span><p class=\"mq-relbar-card-sub\">cuves 0,5 \/ 1 \/ 2 mm<\/p><\/a><a class=\"mq-relbar-card\" href=\"https:\/\/machinedquartz.com\/fr\/cuves-cylindriques\/\"><span class=\"mq-relbar-card-emoji\">\ud83e\udd41<\/span><span class=\"mq-relbar-card-title\">Cylindrique<\/span><p class=\"mq-relbar-card-sub\">R\u00e9flectance diffuse UV-Vis<\/p><\/a><a class=\"mq-relbar-card\" href=\"https:\/\/machinedquartz.com\/fr\/cuves-ir-quartz\/\"><span class=\"mq-relbar-card-emoji\">\ud83d\udce1<\/span><span class=\"mq-relbar-card-title\">NIR \/ IR<\/span><p class=\"mq-relbar-card-sub\">190\u20132 500 nm NIR\/IR<\/p><\/a><a class=\"mq-relbar-card\" href=\"https:\/\/machinedquartz.com\/fr\/microcuves\/\"><span class=\"mq-relbar-card-emoji\">\ud83d\udd2c<\/span><span class=\"mq-relbar-card-title\">Micro \/ Sub-micro<\/span><p class=\"mq-relbar-card-sub\">volumes 5\u2013200 \u00b5L<\/p><\/a><\/div><\/div>\n\n<div class=\"csg-toc\">\n  <h3>Sommaire<\/h3>\n  <ol>\n    <li><a href=\"#what-is\">Qu\u2019est-ce que le trajet optique d\u2019une cuve ?<\/a><\/li>\n    <li><a href=\"#beer-lambert\">La loi de Beer-Lambert expliqu\u00e9e<\/a><\/li>\n    <li><a href=\"#standard-lengths\">Trajets optiques standard & usages<\/a><\/li>\n    <li><a href=\"#how-to-choose\">Comment choisir le bon trajet optique<\/a><\/li>\n    <li><a href=\"#short-path\">Cuves \u00e0 court trajet (<10 mm)<\/a><\/li>\n    <li><a href=\"#long-path\">Long path length cuvettes (>10 mm)<\/a><\/li>\n    <li><a href=\"#z-height\">Trajet optique vs hauteur Z<\/a><\/li>\n    <li><a href=\"#accuracy\">Exactitude & tol\u00e9rance du trajet optique<\/a><\/li>\n    <li><a href=\"#calculator\">Calculateur de trajet optique<\/a><\/li>\n    <li><a href=\"#faq\">Questions fr\u00e9quentes<\/a><\/li>\n  <\/ol>\n<\/div>\n\n<style>\n.cplp-picker { background:#f0f7ff; border:2px solid #1a73e8; border-radius:12px; padding:24px; margin:32px 0; }\n.cplp-picker h3 { margin:0 0 16px; color:#1a2a6c; font-size:20px; }\n.cplp-table { width:100%; border-collapse:collapse; background:#fff; border-radius:8px; overflow:hidden; }\n.cplp-table th { background:#1a2a6c; color:#fff; padding:10px 12px; text-align:left; font-size:13px; }\n.cplp-table td { padding:10px 12px; border-top:1px solid #e8eaf0; font-size:14px; vertical-align:top; }\n.cplp-table tr:hover td { background:#f7f9ff; }\n.cplp-table .pl { font-weight:700; color:#1a2a6c; white-space:nowrap; }\n.cplp-table a { color:#1a73e8; text-decoration:none; font-weight:600; }\n.cplp-table a:hover { text-decoration:underline; }\n.cplp-jump { display:inline-block; margin-top:14px; background:#1a2a6c; color:#fff; padding:10px 18px; border-radius:6px; text-decoration:none; font-weight:600; font-size:14px; }\n.cplp-jump:hover { background:#1a73e8; color:#fff; }\n<\/style>\n<div class=\"cplp-picker\">\n  <h3>S\u00e9lecteur rapide de trajet optique<\/h3>\n  <p style=\"margin:0 0 14px;font-size:14px;color:#444;\">Choisissez la ligne qui correspond \u00e0 votre \u00e9chantillon, sautez au bon produit :<\/p>\n  <table class=\"cplp-table\">\n    <thead><tr><th>Trajet optique<\/th><th>Id\u00e9al pour<\/th><th>Plage de concentration typique<\/th><th>Produit MQ<\/th><\/tr><\/thead>\n    <tbody>\n      <tr><td class=\"pl\">1 mm<\/td><td>\u00c9chantillons tr\u00e8s concentr\u00e9s, prot\u00e9ine A280, ADN\/ARN non dilu\u00e9<\/td><td>1\u201310 mg\/mL protein, >acide nucl\u00e9ique \u00e0 100 ng\/\u00b5L<\/td><td><a href=\"https:\/\/machinedquartz.com\/cuvettes-and-cells-size-chart\/\">Standard 80 \/ Sintered 83<\/a><\/td><\/tr>\n      <tr><td class=\"pl\">5 mm<\/td><td>Concentration mod\u00e9r\u00e9e, \u00e9chantillons semi-micro<\/td><td>prot\u00e9ine 0,5\u20135 mg\/mL, solutions m\u00e8res de colorant<\/td><td><a href=\"https:\/\/machinedquartz.com\/cuvettes-and-cells-size-chart\/\">Standard 80<\/a><\/td><\/tr>\n      <tr><td class=\"pl\">10 mm<\/td><td>R\u00e9f\u00e9rence standard, la plupart des dosages UV-Vis, cin\u00e9tique<\/td><td>La plupart du travail courant, A = 0,1\u20131,0 dans la plage cible<\/td><td><a href=\"https:\/\/machinedquartz.com\/cuvettes-and-cells-size-chart\/\">Standard 80 \/ Molded 83<\/a><\/td><\/tr>\n      <tr><td class=\"pl\">20 mm<\/td><td>\u00c9chantillons dilu\u00e9s, eau environnementale, faible absorbance<\/td><td>Organiques traces, biomol\u00e9cules dilu\u00e9es<\/td><td><a href=\"https:\/\/machinedquartz.com\/cuvettes-and-cells-size-chart\/\">Standard 80<\/a><\/td><\/tr>\n      <tr><td class=\"pl\">50 mm<\/td><td>\u00c9chantillons tr\u00e8s dilu\u00e9s, qualit\u00e9 de l\u2019eau, analyse de r\u00e9sidus<\/td><td>polluants \u00e0 \u00b5g\/L, analytes sub-\u00b5M<\/td><td><a href=\"\/cuvettes-and-cells-custom-fabrication\/\">Sur mesure \u2014 demander un devis<\/a><\/td><\/tr>\n      <tr><td class=\"pl\">100 mm<\/td><td>Analyse ultra-trace, cuves d\u2019absorption gazeuse<\/td><td>analytes \u00e0 ng\/L, gaz basse pression<\/td><td><a href=\"\/cuvettes-and-cells-custom-fabrication\/\">Sur mesure \u2014 demander un devis<\/a><\/td><\/tr>\n    <\/tbody>\n  <\/table>\n  <a href=\"#path-length-calculator\" class=\"cplp-jump\">Aller au calculateur \u2192<\/a>\n<\/div>\n\n<style>\n.cplv-section { margin:48px 0; }\n.cplv-section h3 { color:#1a2a6c; font-size:22px; margin:0 0 8px; }\n.cplv-section p.cplv-intro { color:#555; font-size:14px; margin:0 0 18px; }\n.cplv-table-wrap { overflow-x:auto; }\n.cplv-table { width:100%; min-width:680px; border-collapse:collapse; background:#fff; border:1px solid #e8eaf0; border-radius:8px; overflow:hidden; }\n.cplv-table thead th { background:#1a2a6c; color:#fff; padding:12px 10px; font-size:13px; text-align:center; font-weight:600; }\n.cplv-table thead th:first-child { background:#0f1d54; text-align:left; }\n.cplv-table tbody td { padding:10px; border-top:1px solid #e8eaf0; font-size:13px; text-align:center; vertical-align:middle; }\n.cplv-table tbody td:first-child { text-align:left; font-weight:700; color:#1a2a6c; background:#f7f9ff; white-space:nowrap; }\n.cplv-cell-yes { background:#dcfce7; color:#15803d; font-weight:600; }\n.cplv-cell-best { background:#86efac; color:#166534; font-weight:700; }\n.cplv-cell-no { background:#f3f4f6; color:#9ca3af; }\n.cplv-legend { margin-top:14px; font-size:12px; color:#555; display:flex; gap:18px; flex-wrap:wrap; }\n.cplv-legend span { display:inline-flex; align-items:center; gap:6px; }\n.cplv-legend i { display:inline-block; width:14px; height:14px; border-radius:3px; }\n.cplv-takeaway { background:#fef3c7; border-left:4px solid #d97706; padding:14px 18px; margin-top:18px; border-radius:6px; font-size:14px; line-height:1.6; }\n.cplv-takeaway strong { color:#92400e; }\n<\/style>\n<div class=\"cplv-section\">\n  <h3>Matrice trajet optique \u00d7 volume d\u2019\u00e9chantillon<\/h3>\n  <p class=\"cplv-intro\">Diff\u00e9rentes g\u00e9om\u00e9tries de cuve arbitrent entre trajet optique et volume d\u2019\u00e9chantillon. Utilisez cette matrice pour trouver la bonne combinaison selon la taille de votre \u00e9chantillon :<\/p>\n  <div class=\"cplv-table-wrap\">\n    <table class=\"cplv-table\">\n      <thead>\n        <tr>\n          <th>Volume d\u2019\u00e9chantillon<\/th>\n          <th>1 mm<\/th>\n          <th>2 mm<\/th>\n          <th>5 mm<\/th>\n          <th>10 mm<\/th>\n          <th>20 mm<\/th>\n          <th>50 mm<\/th>\n          <th>100 mm<\/th>\n        <\/tr>\n      <\/thead>\n      <tbody>\n        <tr>\n          <td>< 50 \u00b5L (ultra-micro)<\/td>\n          <td class=\"cplv-cell-best\">Id\u00e9al<\/td>\n          <td class=\"cplv-cell-yes\">OK<\/td>\n          <td class=\"cplv-cell-yes\">OK<\/td>\n          <td class=\"cplv-cell-yes\">OK*<\/td>\n          <td class=\"cplv-cell-no\">\u2014<\/td>\n          <td class=\"cplv-cell-no\">\u2014<\/td>\n          <td class=\"cplv-cell-no\">\u2014<\/td>\n        <\/tr>\n        <tr>\n          <td>50 \u2013 500 \u00b5L (sub-micro)<\/td>\n          <td class=\"cplv-cell-yes\">OK<\/td>\n          <td class=\"cplv-cell-yes\">OK<\/td>\n          <td class=\"cplv-cell-best\">Id\u00e9al<\/td>\n          <td class=\"cplv-cell-best\">Id\u00e9al<\/td>\n          <td class=\"cplv-cell-yes\">OK<\/td>\n          <td class=\"cplv-cell-no\">\u2014<\/td>\n          <td class=\"cplv-cell-no\">\u2014<\/td>\n        <\/tr>\n        <tr>\n          <td>500 \u00b5L \u2013 1,4 mL (semi-micro)<\/td>\n          <td class=\"cplv-cell-yes\">OK<\/td>\n          <td class=\"cplv-cell-yes\">OK<\/td>\n          <td class=\"cplv-cell-yes\">OK<\/td>\n          <td class=\"cplv-cell-best\">Id\u00e9al<\/td>\n          <td class=\"cplv-cell-best\">Id\u00e9al<\/td>\n          <td class=\"cplv-cell-yes\">OK<\/td>\n          <td class=\"cplv-cell-no\">\u2014<\/td>\n        <\/tr>\n        <tr>\n          <td>1,4 \u2013 3,5 mL (standard)<\/td>\n          <td class=\"cplv-cell-no\">\u2014<\/td>\n          <td class=\"cplv-cell-no\">\u2014<\/td>\n          <td class=\"cplv-cell-yes\">OK<\/td>\n          <td class=\"cplv-cell-best\">Id\u00e9al<\/td>\n          <td class=\"cplv-cell-best\">Id\u00e9al<\/td>\n          <td class=\"cplv-cell-best\">Id\u00e9al<\/td>\n          <td class=\"cplv-cell-yes\">OK<\/td>\n        <\/tr>\n        <tr>\n          <td>3,5 \u2013 10 mL (macro)<\/td>\n          <td class=\"cplv-cell-no\">\u2014<\/td>\n          <td class=\"cplv-cell-no\">\u2014<\/td>\n          <td class=\"cplv-cell-no\">\u2014<\/td>\n          <td class=\"cplv-cell-yes\">OK<\/td>\n          <td class=\"cplv-cell-best\">Id\u00e9al<\/td>\n          <td class=\"cplv-cell-best\">Id\u00e9al<\/td>\n          <td class=\"cplv-cell-best\">Id\u00e9al<\/td>\n        <\/tr>\n        <tr>\n          <td>> 10 mL (circulation \/ grand)<\/td>\n          <td class=\"cplv-cell-no\">\u2014<\/td>\n          <td class=\"cplv-cell-no\">\u2014<\/td>\n          <td class=\"cplv-cell-no\">\u2014<\/td>\n          <td class=\"cplv-cell-no\">\u2014<\/td>\n          <td class=\"cplv-cell-yes\">OK<\/td>\n          <td class=\"cplv-cell-best\">Id\u00e9al<\/td>\n          <td class=\"cplv-cell-best\">Id\u00e9al<\/td>\n        <\/tr>\n      <\/tbody>\n    <\/table>\n  <\/div>\n  <div class=\"cplv-legend\">\n    <span><i style=\"background:#86efac;\"><\/i>Id\u00e9al \u2014 g\u00e9om\u00e9trie accord\u00e9e, sans gaspillage, remplissage de faisceau optimal<\/span>\n    <span><i style=\"background:#dcfce7;\"><\/i>OK \u2014 fonctionne mais sous-optimal (exc\u00e8s de volume ou \u00e9cr\u00eatage du faisceau)<\/span>\n    <span><i style=\"background:#f3f4f6;\"><\/i>\u2014 D\u00e9conseill\u00e9 (mauvaise g\u00e9om\u00e9trie)<\/span>\n  <\/div>\n  <div class=\"cplv-takeaway\">\n    <strong>En r\u00e9sum\u00e9 :<\/strong> Accordez d\u2019abord le trajet optique \u00e0 votre volume d\u2019\u00e9chantillon, puis v\u00e9rifiez que votre absorbance tombe dans la zone id\u00e9ale 0,2\u20131,0. *Les \u00e9chantillons sous 50 \u00b5L dans un trajet de 10 mm n\u00e9cessitent une sub-microcuve \u00e0 largeur interne r\u00e9duite \u2014 voir notre <a href=\"https:\/\/machinedquartz.com\/fr\/dimension-z-cuves-spectrophotometre\/\" style=\"color:#1a2a6c;font-weight:600;\">guide de la dimension Z<\/a> pour la compatibilit\u00e9 avec votre spectrophotom\u00e8tre.\n  <\/div>\n<\/div>\n\n<div id=\"what-is\">\n<p class=\"csg-label\">Section 1<\/p>\n<h2>Qu\u2019est-ce que le trajet optique d\u2019une cuve ?<\/h2>\n\n<div class=\"csg-img-row\">\n  <div class=\"csg-img-col\">\n    <img decoding=\"async\" src=\"https:\/\/machinedquartz.com\/wp-content\/uploads\/2026\/04\/csg-path-length-new-1-1mm-short-path-quartz-cuvette.jpg\" alt=\"Cuve en quartz \u00e0 court trajet 1 mm pour \u00e9chantillons concentr\u00e9s\" loading=\"lazy\">\n    <p class=\"csg-img-caption\">1 mm \u00b7 \u00e9chantillons concentr\u00e9s \u00b7 forte absorbance<\/p>\n  <\/div>\n  <div class=\"csg-img-col\">\n    <img decoding=\"async\" src=\"https:\/\/machinedquartz.com\/wp-content\/uploads\/2026\/04\/csg-path-length-new-2-10mm-standard-quartz-cuvette-2.jpg\" alt=\"Cuve en quartz \u00e0 trajet standard 10 mm \u2014 la plus courante\" loading=\"lazy\">\n    <p class=\"csg-img-caption\">10 mm \u00b7 standard \u00b7 la plupart des applications<\/p>\n  <\/div>\n  <div class=\"csg-img-col\">\n    <img decoding=\"async\" src=\"https:\/\/machinedquartz.com\/wp-content\/uploads\/2026\/04\/csg-path-length-new-3-100mm-long-path-quartz-cuvette.jpg\" alt=\"Cuve en quartz \u00e0 long trajet 100 mm pour \u00e9chantillons dilu\u00e9s\" loading=\"lazy\">\n    <p class=\"csg-img-caption\">100 mm \u00b7 \u00e9chantillons dilu\u00e9s \u00b7 analyse de traces<\/p>\n  <\/div>\n<\/div>\n\n<p>Le trajet optique (aussi appel\u00e9 chemin optique ou trajet de lumi\u00e8re) est la distance qu\u2019un faisceau de lumi\u00e8re parcourt \u00e0 travers l\u2019\u00e9chantillon dans une cuve. Il se mesure en millim\u00e8tres et \u00e9gale la largeur interne de la cuve mesur\u00e9e selon la direction du faisceau \u2014 pr\u00e9cis\u00e9ment, la distance entre les deux fen\u00eatres optiquement polies.<\/p>\n<p>Pour une cuve standard de 10 mm, la lumi\u00e8re parcourt exactement 10 mm \u00e0 travers l\u2019\u00e9chantillon. Pour une <a href=\"https:\/\/machinedquartz.com\/cuvettes-and-cells-size-chart\/\">cuve de 1 mm<\/a>, elle parcourt 1 mm. Cette seule dimension a un effet direct et lin\u00e9aire sur la quantit\u00e9 de lumi\u00e8re absorb\u00e9e par l\u2019\u00e9chantillon, ce que d\u00e9crit la loi de Beer-Lambert.<\/p>\n\n<!-- SVG 1: Cross-section diagram \u2014 light beam through cuvette -->\n<div style=\"background:#f7f8fc;border-radius:12px;padding:20px 16px 12px;margin:20px 0 24px;\">\n<svg viewBox=\"0 0 660 200\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" style=\"width:100%;max-width:660px;display:block;margin:0 auto;\" aria-label=\"Coupe vue de dessus d'une cuve montrant le trajet du faisceau \u00e0 travers l'\u00e9chantillon\">\n  <rect width=\"660\" height=\"200\" fill=\"#f7f8fc\" rx=\"8\"\/>\n  <text x=\"330\" y=\"18\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"12\" font-weight=\"700\" fill=\"#233a95\" letter-spacing=\"1\">COUPE DE LA CUVE (vue de dessus)<\/text>\n\n  <!-- Outer cuvette body -->\n  <rect x=\"200\" y=\"35\" width=\"260\" height=\"130\" rx=\"5\" fill=\"none\" stroke=\"#233a95\" stroke-width=\"2.5\"\/>\n  <!-- Left quartz wall (thick) -->\n  <rect x=\"200\" y=\"35\" width=\"35\" height=\"130\" fill=\"rgba(147,197,253,0.4)\" stroke=\"#233a95\" stroke-width=\"1.5\"\/>\n  <!-- Right quartz wall (thick) -->\n  <rect x=\"425\" y=\"35\" width=\"35\" height=\"130\" fill=\"rgba(147,197,253,0.4)\" stroke=\"#233a95\" stroke-width=\"1.5\"\/>\n  <!-- Top\/bottom walls (opaque sides) -->\n  <rect x=\"235\" y=\"35\" width=\"190\" height=\"22\" fill=\"rgba(100,116,139,0.25)\" stroke=\"#64748b\" stroke-width=\"1\"\/>\n  <rect x=\"235\" y=\"143\" width=\"190\" height=\"22\" fill=\"rgba(100,116,139,0.25)\" stroke=\"#64748b\" stroke-width=\"1\"\/>\n\n  <!-- Sample interior -->\n  <rect x=\"235\" y=\"57\" width=\"190\" height=\"86\" fill=\"rgba(120,60,200,0.12)\"\/>\n\n  <!-- Path length arrow (horizontal, inside sample) -->\n  <line x1=\"235\" y1=\"175\" x2=\"425\" y2=\"175\" stroke=\"#233a95\" stroke-width=\"1.8\"\/>\n  <polygon points=\"235,171 235,179 226,175\" fill=\"#233a95\"\/>\n  <polygon points=\"425,171 425,179 434,175\" fill=\"#233a95\"\/>\n  <text x=\"330\" y=\"191\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"11.5\" font-weight=\"700\" fill=\"#233a95\">Trajet optique (l) \u2014 mesur\u00e9 ici<\/text>\n\n  <!-- Light beam arrows through sample -->\n  <defs>\n    <marker id=\"arrowA\" markerWidth=\"7\" markerHeight=\"5\" refX=\"7\" refY=\"2.5\" orient=\"auto\"><polygon points=\"0,0 7,2.5 0,5\" fill=\"#f59e0b\"\/><\/marker>\n  <\/defs>\n  <line x1=\"50\" y1=\"100\" x2=\"197\" y2=\"100\" stroke=\"#f59e0b\" stroke-width=\"3.5\" marker-end=\"url(#arrowA)\"\/>\n  <!-- beam inside sample (dashed) -->\n  <line x1=\"235\" y1=\"100\" x2=\"422\" y2=\"100\" stroke=\"#f59e0b\" stroke-width=\"3\" stroke-dasharray=\"7,4\" opacity=\"0.75\"\/>\n  <!-- exiting beam (attenuated) -->\n  <defs>\n    <marker id=\"arrowB\" markerWidth=\"7\" markerHeight=\"5\" refX=\"7\" refY=\"2.5\" orient=\"auto\"><polygon points=\"0,0 7,2.5 0,5\" fill=\"#ef4444\"\/><\/marker>\n  <\/defs>\n  <line x1=\"460\" y1=\"100\" x2=\"610\" y2=\"100\" stroke=\"#ef4444\" stroke-width=\"2.2\" marker-end=\"url(#arrowB)\"\/>\n\n  <!-- Labels -->\n  <text x=\"123\" y=\"88\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"11\" fill=\"#b45309\" font-weight=\"600\">Lumi\u00e8re<\/text>\n  <text x=\"123\" y=\"100\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"11\" fill=\"#b45309\" font-weight=\"600\">incidente (I\u2080)<\/text>\n  <text x=\"535\" y=\"88\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"11\" fill=\"#b91c1c\" font-weight=\"600\">Lumi\u00e8re<\/text>\n  <text x=\"535\" y=\"100\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"11\" fill=\"#b91c1c\" font-weight=\"600\">transmise (I)<\/text>\n\n  <!-- Optical window labels -->\n  <text x=\"217\" y=\"52\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"9.5\" fill=\"#1e40af\">Fen\u00eatre<\/text>\n  <text x=\"217\" y=\"62\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"9.5\" fill=\"#1e40af\">optique<\/text>\n  <text x=\"443\" y=\"52\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"9.5\" fill=\"#1e40af\">Fen\u00eatre<\/text>\n  <text x=\"443\" y=\"62\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"9.5\" fill=\"#1e40af\">optique<\/text>\n\n  <!-- Opaque side labels -->\n  <text x=\"330\" y=\"49\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"9.5\" fill=\"#475569\">paroi lat\u00e9rale opaque<\/text>\n  <text x=\"330\" y=\"158\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"9.5\" fill=\"#475569\">paroi lat\u00e9rale opaque<\/text>\n\n  <!-- Sample label -->\n  <text x=\"330\" y=\"97\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"11\" fill=\"#6b21a8\" font-weight=\"600\">\u00e9chantillon<\/text>\n  <text x=\"330\" y=\"110\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"10\" fill=\"#6b21a8\">A = log(I\u2080\/I)<\/text>\n<\/svg>\n<p style=\"text-align:center;font-size:12px;color:#888;margin:6px 0 0;\">Coupe vue de dessus : la lumi\u00e8re entre par une fen\u00eatre optique, parcourt tout le trajet optique \u00e0 travers l\u2019\u00e9chantillon, et ressort par la fen\u00eatre oppos\u00e9e. Les deux parois lat\u00e9rales sont opaques.<\/p>\n<\/div>\n\n<div class=\"csg-highlight\">\n  <strong>D\u00e9finition cl\u00e9 :<\/strong> Trajet optique = la distance interne entre les deux fen\u00eatres optiquement polies d\u2019une cuve, mesur\u00e9e selon la direction du faisceau. Le trajet optique standard est de 10 mm. Ce n\u2019est pas la m\u00eame chose que la hauteur Z (voir Section 7).\n<\/div>\n\n<div style=\"background:#fff8e1;border:2px solid #f59e0b;border-radius:10px;padding:22px 26px;margin:24px 0;\">\n  <p style=\"font-size:11px;font-weight:700;letter-spacing:1.5px;text-transform:uppercase;color:#92400e;margin:0 0 8px;\">D\u00e9finition<\/p>\n  <h3 style=\"font-size:18px;font-weight:800;color:#1a1a2e;margin:0 0 10px;\">Qu\u2019est-ce que le trajet optique en spectroscopie ?<\/h3>\n  <p style=\"font-size:15px;color:#333;line-height:1.7;margin:0 0 10px;\"><strong>Le trajet optique en spectroscopie est la distance qu\u2019un faisceau de lumi\u00e8re parcourt \u00e0 travers un \u00e9chantillon dans une cuve.<\/strong> Il se mesure en millim\u00e8tres (mm) ou centim\u00e8tres (cm) et \u00e9gale l\u2019\u00e9cart interne entre les deux fen\u00eatres optiques de la cuve, selon l\u2019axe du faisceau. Selon la loi de Beer-Lambert (A = \u03b5 \u00b7 c \u00b7 l), le trajet optique contr\u00f4le directement et lin\u00e9airement la quantit\u00e9 de lumi\u00e8re absorb\u00e9e : doubler le trajet double l\u2019absorbance \u00e0 concentration d\u2019\u00e9chantillon \u00e9gale. Le trajet optique standard de la spectrophotom\u00e9trie UV-Vis est de 10 mm (1 cm).<\/p>\n  <p style=\"font-size:13px;color:#78350f;margin:0;\"><strong>Aussi appel\u00e9 :<\/strong> chemin optique, longueur de trajet optique, trajet de lumi\u00e8re<\/p>\n<\/div>\n<\/div>\n\n<div id=\"beer-lambert\">\n<p class=\"csg-label\">Section 2<\/p>\n<h2>Loi de Beer-Lambert : pourquoi le trajet optique compte<\/h2>\n\n<p>La loi de Beer-Lambert est la relation fondamentale qui r\u00e9git toutes les mesures d\u2019absorbance UV-Vis. Elle \u00e9nonce :<\/p>\n\n<div class=\"csg-formula\">\n  <div class=\"csg-formula-eq\">A = \u03b5 \u00b7 c \u00b7 l<\/div>\n  <div class=\"csg-formula-key\">\n    <span>A<\/span> = Absorbance (sans dimension)<br>\n    <span>\u03b5<\/span> = Absorptivit\u00e9 molaire (L mol\u207b\u00b9 cm\u207b\u00b9) \u2014 une propri\u00e9t\u00e9 de la mol\u00e9cule \u00e0 une longueur d\u2019onde donn\u00e9e<br>\n    <span>c<\/span> = Concentration (mol L\u207b\u00b9)<br>\n    <span>l<\/span> = Trajet optique (cm) \u2014 la dimension de cuve que vous contr\u00f4lez\n  <\/div>\n<\/div>\n\n<p>Comme le trajet optique (<em>l<\/em>) multiplie directement la concentration (<em>c<\/em>), doubler le trajet optique double l\u2019absorbance pour une concentration donn\u00e9e. Le trajet optique est donc un levier puissant pour ajuster la sensibilit\u00e9 :<\/p>\n\n<div class=\"csg-card-grid\">\n  <div class=\"csg-card\">\n    <div class=\"csg-card-icon\">\ud83d\udd3c<\/div>\n    <h3>Augmenter le trajet optique<\/h3>\n    <p>Absorbance plus \u00e9lev\u00e9e pour la m\u00eame concentration. \u00c0 utiliser quand les \u00e9chantillons sont dilu\u00e9s et que l\u2019absorbance serait sinon trop faible \u00e0 mesurer avec exactitude (<0.05 A). Long path cuvettes (<a href=\"\/cuvettes-and-cells-custom-fabrication\/\">50\u2013100 mm<\/a>) \u00e9tendent la d\u00e9tection aux concentrations traces.<\/p>\n  <\/div>\n  <div class=\"csg-card\">\n    <div class=\"csg-card-icon\">\ud83d\udd3d<\/div>\n    <h3>Diminuer le trajet optique<\/h3>\n    <p>Lower absorbance for the same concentration. Use when samples are highly concentrated and would saturate the detector (>Absorbance plus faible pour la m\u00eame concentration. \u00c0 utiliser quand les \u00e9chantillons sont concentr\u00e9s et saturent une cuve standard (2,0\u20133,0 A). Les cuves \u00e0 court trajet (0,1\u20135 mm) permettent une mesure directe sans dilution.<\/p>\n  <\/div>\n  <div class=\"csg-card\">\n    <div class=\"csg-card-icon\">\u2696\ufe0f<\/div>\n    <h3>Plage d\u2019absorbance optimale<\/h3>\n    <p>La plage lin\u00e9aire de la loi de Beer-Lambert est de 0,1\u20131,0 unit\u00e9 d\u2019absorbance pour la plupart des spectrophotom\u00e8tres. Choisissez ensemble le trajet optique et la concentration pour que votre mesure tombe dans cette fen\u00eatre, pour la meilleure exactitude.<\/p>\n  <\/div>\n<\/div>\n\n<div class=\"csg-highlight\">\n  <strong>R\u00e8gle pratique :<\/strong> If your absorbance is too high (>si votre absorbance est trop \u00e9lev\u00e9e (au-dessus d\u2019environ 1,5 A), utilisez un trajet plus court ou diluez l\u2019\u00e9chantillon. Si votre absorbance est trop faible (sous environ 0,1 A), utilisez un trajet plus long ou concentrez l\u2019\u00e9chantillon.<0.05 A), use a longer path length or increase concentration. The 10 mm standard path is designed for dilute aqueous samples in the Beer-Lambert linear range.\n<\/div>\n\n<p>Notez que dans l\u2019\u00e9quation de Beer-Lambert, le trajet optique est en <strong>centim\u00e8tres<\/strong> (cm), pas en millim\u00e8tres. Convertissez toujours les mm en cm en divisant par 10 avant d\u2019utiliser la formule.<\/p>\n\n<div style=\"background:#f0f3fc;border-radius:10px;padding:20px 24px;margin:20px 0 28px;\">\n  <p style=\"font-size:11px;font-weight:700;letter-spacing:1.5px;text-transform:uppercase;color:#233a95;margin:0 0 10px;\">R\u00e9f\u00e9rence rapide : conversion mm \u2192 cm pour les calculs de Beer-Lambert<\/p>\n  <table style=\"width:100%;border-collapse:collapse;font-size:14px;\">\n    <thead>\n      <tr style=\"background:#233a95;color:#fff;\">\n        <th style=\"padding:9px 14px;text-align:left;border-radius:6px 0 0 0;\">Trajet optique de la cuve (mm)<\/th>\n        <th style=\"padding:9px 14px;text-align:left;\">Trajet optique dans la formule (cm)<\/th>\n        <th style=\"padding:9px 14px;text-align:left;border-radius:0 6px 0 0;\">Sensibilit\u00e9 vs 10 mm<\/th>\n      <\/tr>\n    <\/thead>\n    <tbody>\n      <tr style=\"background:#f7f8fc;\"><td style=\"padding:8px 14px;border-bottom:1px solid #e8eaf2;font-weight:600;\">1 mm<\/td><td style=\"padding:8px 14px;border-bottom:1px solid #e8eaf2;\">0,1 cm<\/td><td style=\"padding:8px 14px;border-bottom:1px solid #e8eaf2;\">1\/10\u00d7<\/td><\/tr>\n      <tr style=\"background:#fff;\"><td style=\"padding:8px 14px;border-bottom:1px solid #e8eaf2;font-weight:600;\">5 mm<\/td><td style=\"padding:8px 14px;border-bottom:1px solid #e8eaf2;\">0,5 cm<\/td><td style=\"padding:8px 14px;border-bottom:1px solid #e8eaf2;\">1\/2\u00d7<\/td><\/tr>\n      <tr style=\"background:#f7f8fc;\"><td style=\"padding:8px 14px;border-bottom:1px solid #e8eaf2;font-weight:600;\">10 mm (standard)<\/td><td style=\"padding:8px 14px;border-bottom:1px solid #e8eaf2;\">1 cm<\/td><td style=\"padding:8px 14px;border-bottom:1px solid #e8eaf2;\">1\u00d7 (r\u00e9f\u00e9rence)<\/td><\/tr>\n      <tr style=\"background:#fff;\"><td style=\"padding:8px 14px;border-bottom:1px solid #e8eaf2;font-weight:600;\">50 mm<\/td><td style=\"padding:8px 14px;border-bottom:1px solid #e8eaf2;\">5 cm<\/td><td style=\"padding:8px 14px;border-bottom:1px solid #e8eaf2;\">5\u00d7<\/td><\/tr>\n      <tr style=\"background:#f7f8fc;\"><td style=\"padding:8px 14px;font-weight:600;\">100 mm<\/td><td style=\"padding:8px 14px;\">10 cm<\/td><td style=\"padding:8px 14px;\">10\u00d7<\/td><\/tr>\n    <\/tbody>\n  <\/table>\n  <p style=\"font-size:12px;color:#666;margin:10px 0 0;\">Exemple : cuve de 1 mm, prot\u00e9ine \u00e0 1 mg\/mL (\u03b5 = 43 824 L mol\u207b\u00b9 cm\u207b\u00b9) \u2192 A = 43 824 \u00d7 c \u00d7 0,1 <strong>0.1<\/strong> cm. Utilisez toujours la valeur en cm dans la formule.<\/p>\n<\/div>\n\n<!-- SVG 2: Beer-Lambert Law visual explainer -->\n<div style=\"background:#1a1a2e;border-radius:12px;padding:20px 16px 16px;margin:24px 0 0;\">\n<svg viewBox=\"0 0 680 260\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" style=\"width:100%;max-width:680px;display:block;margin:0 auto;\" aria-label=\"Explicatif visuel de la loi de Beer-Lambert montrant comment l'absorbance d\u00e9pend du trajet optique et de la concentration\">\n  <rect width=\"680\" height=\"260\" fill=\"#1a1a2e\" rx=\"10\"\/>\n  <text x=\"340\" y=\"22\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"13\" font-weight=\"700\" fill=\"#a5c0ff\" letter-spacing=\"1\">LOI DE BEER-LAMBERT : A = \u03b5 \u00b7 c \u00b7 l<\/text>\n  <!-- \u03b5 box -->\n  <rect x=\"30\" y=\"38\" width=\"175\" height=\"90\" rx=\"8\" fill=\"rgba(59,130,246,0.15)\" stroke=\"#3b82f6\" stroke-width=\"1.5\"\/>\n  <text x=\"117\" y=\"62\" text-anchor=\"middle\" font-family=\"Georgia,serif\" font-size=\"28\" font-weight=\"700\" fill=\"#93c5fd\">\u03b5<\/text>\n  <text x=\"117\" y=\"82\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"11\" fill=\"#93c5fd\" font-weight=\"700\">Absorptivit\u00e9 molaire<\/text>\n  <text x=\"117\" y=\"97\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"10\" fill=\"rgba(147,197,253,0.75)\">(L mol\u207b\u00b9 cm\u207b\u00b9)<\/text>\n  <text x=\"117\" y=\"116\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"10\" fill=\"rgba(147,197,253,0.6)\">Fix\u00e9e par la mol\u00e9cule<\/text>\n  <text x=\"117\" y=\"128\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"10\" fill=\"rgba(147,197,253,0.6)\">& la longueur d\u2019onde<\/text>\n  <text x=\"216\" y=\"92\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"22\" fill=\"#a5c0ff\" font-weight=\"300\">\u00d7<\/text>\n  <!-- c box -->\n  <rect x=\"230\" y=\"38\" width=\"175\" height=\"90\" rx=\"8\" fill=\"rgba(168,85,247,0.15)\" stroke=\"#a855f7\" stroke-width=\"1.5\"\/>\n  <text x=\"317\" y=\"62\" text-anchor=\"middle\" font-family=\"Georgia,serif\" font-size=\"28\" font-weight=\"700\" fill=\"#d8b4fe\">c<\/text>\n  <text x=\"317\" y=\"82\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"11\" fill=\"#d8b4fe\" font-weight=\"700\">Concentration<\/text>\n  <text x=\"317\" y=\"97\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"10\" fill=\"rgba(216,180,254,0.75)\">(mol L\u207b\u00b9)<\/text>\n  <text x=\"317\" y=\"116\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"10\" fill=\"rgba(216,180,254,0.6)\">Fix\u00e9e par votre \u00e9chantillon<\/text>\n  <text x=\"416\" y=\"92\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"22\" fill=\"#a5c0ff\" font-weight=\"300\">\u00d7<\/text>\n  <!-- l box (highlighted) -->\n  <rect x=\"430\" y=\"38\" width=\"220\" height=\"90\" rx=\"8\" fill=\"rgba(34,197,94,0.18)\" stroke=\"#22c55e\" stroke-width=\"2\"\/>\n  <text x=\"540\" y=\"62\" text-anchor=\"middle\" font-family=\"Georgia,serif\" font-size=\"28\" font-weight=\"700\" fill=\"#86efac\">l<\/text>\n  <text x=\"540\" y=\"82\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"11\" fill=\"#86efac\" font-weight=\"700\">Trajet optique (cm)<\/text>\n  <text x=\"540\" y=\"97\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"10\" fill=\"rgba(134,239,172,0.8)\">mm \u00f7 10 = cm<\/text>\n  <text x=\"540\" y=\"116\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"11\" fill=\"#4ade80\" font-weight=\"700\">\u2190 VOUS le contr\u00f4lez<\/text>\n  <text x=\"540\" y=\"128\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"10\" fill=\"rgba(134,239,172,0.7)\">en choisissant la cuve<\/text>\n  <!-- Result line -->\n  <text x=\"340\" y=\"162\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"13\" fill=\"#a5c0ff\">= <tspan font-weight=\"700\" fill=\"#fff\">Absorbance (A)<\/tspan> \u2014 log(I\u2080\/I), mesur\u00e9e par le spectrophotom\u00e8tre<\/text>\n  <!-- Bar chart: same sample, different path lengths -->\n  <text x=\"55\" y=\"190\" font-family=\"Arial,sans-serif\" font-size=\"10.5\" fill=\"#a5c0ff\" font-weight=\"700\">M\u00eame \u00e9chantillon \u2014 seul le trajet optique change :<\/text>\n  <line x1=\"50\" y1=\"241\" x2=\"365\" y2=\"241\" stroke=\"#475569\" stroke-width=\"1\"\/>\n  <rect x=\"55\"  y=\"241\" width=\"32\" height=\"-20\"  fill=\"#3b82f6\" rx=\"2\"\/>\n  <text x=\"71\"  y=\"257\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"9\" fill=\"#93c5fd\">1 mm<\/text>\n  <text x=\"71\"  y=\"218\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"9\" fill=\"#93c5fd\">0.1\u00d7<\/text>\n  <rect x=\"105\" y=\"241\" width=\"32\" height=\"-50\"  fill=\"#3b82f6\" rx=\"2\" opacity=\"0.8\"\/>\n  <text x=\"121\" y=\"257\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"9\" fill=\"#93c5fd\">5 mm<\/text>\n  <text x=\"121\" y=\"188\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"9\" fill=\"#93c5fd\">0.5\u00d7<\/text>\n  <rect x=\"155\" y=\"241\" width=\"32\" height=\"-100\" fill=\"#22c55e\" rx=\"2\"\/>\n  <text x=\"171\" y=\"257\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"9\" fill=\"#86efac\" font-weight=\"700\">10 mm<\/text>\n  <text x=\"171\" y=\"138\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"9\" fill=\"#86efac\" font-weight=\"700\">1\u00d7 std<\/text>\n  <rect x=\"205\" y=\"241\" width=\"32\" height=\"-140\" fill=\"#f59e0b\" rx=\"2\" opacity=\"0.85\"\/>\n  <text x=\"221\" y=\"257\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"9\" fill=\"#fcd34d\">50 mm<\/text>\n  <text x=\"221\" y=\"99\"  text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"9\" fill=\"#fcd34d\">5\u00d7<\/text>\n  <rect x=\"255\" y=\"241\" width=\"32\" height=\"-140\" fill=\"#ef4444\" rx=\"2\" opacity=\"0.8\"\/>\n  <text x=\"271\" y=\"257\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"9\" fill=\"#fca5a5\">100 mm<\/text>\n  <text x=\"271\" y=\"99\"  text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"9\" fill=\"#fca5a5\">10\u00d7<\/text>\n  <text x=\"275\" y=\"107\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"8\" fill=\"rgba(252,165,165,0.55)\">\u2191tronqu\u00e9<\/text>\n  <text x=\"221\" y=\"107\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"8\" fill=\"rgba(252,211,77,0.55)\">\u2191tronqu\u00e9<\/text>\n  <!-- Insight box -->\n  <rect x=\"390\" y=\"180\" width=\"270\" height=\"72\" rx=\"8\" fill=\"rgba(34,197,94,0.1)\" stroke=\"#22c55e\" stroke-width=\"1.2\"\/>\n  <text x=\"525\" y=\"200\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"11.5\" fill=\"#4ade80\" font-weight=\"700\">\u00c0 retenir en pratique<\/text>\n  <text x=\"525\" y=\"217\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"10.5\" fill=\"rgba(134,239,172,0.9)\">A too high (>A trop \u00e9lev\u00e9e (au-dessus d\u2019environ 1,5) \u2192 cuve plus courte<\/text>\n  <text x=\"525\" y=\"232\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"10.5\" fill=\"rgba(134,239,172,0.9)\">A trop faible (sous environ 0,1) \u2192 cuve plus longue<0.05) \u2192 longer cuvette<\/text>\n  <text x=\"525\" y=\"247\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"10.5\" fill=\"rgba(134,239,172,0.9)\">Zone id\u00e9ale : <tspan font-weight=\"700\" fill=\"#4ade80\">0.1 \u2013 1.0 A<\/tspan><\/text>\n<\/svg>\n<p style=\"text-align:center;font-size:12px;color:#aaa;margin:6px 0 0;background:#1a1a2e;border-radius:0 0 10px 10px;padding-bottom:6px;\">Loi de Beer-Lambert : le trajet optique l est la seule variable que vous choisissez en s\u00e9lectionnant la cuve. Les barres montrent l\u2019absorbance relative \u00e0 la m\u00eame concentration d\u2019\u00e9chantillon \u2014 doubler le trajet optique double l\u2019absorbance.<\/p>\n<\/div>\n<\/div>\n\n<figure style=\"margin:32px 0;text-align:center;\"><svg xmlns=\"http:\/\/www.w3.org\/2000\/svg\" viewBox=\"0 0 800 480\" role=\"img\" aria-label=\"Graphique en barres absorbance vs trajet optique pour le tryptophane \u00e0 280 nm\"><rect x=\"0\" y=\"0\" width=\"800\" height=\"480\" fill=\"#ffffff\"\/><text x=\"400.0\" y=\"32\" text-anchor=\"middle\" font-family=\"Arial,Helvetica,sans-serif\" font-size=\"18\" font-weight=\"700\" fill=\"#1a2a6c\">Absorbance vs trajet optique \u2014 tryptophane \u00e0 280 nm<\/text><text x=\"400.0\" y=\"56\" text-anchor=\"middle\" font-family=\"Arial,Helvetica,sans-serif\" font-size=\"12\" fill=\"#555555\">\u03b5 = 5 500 M\u207b\u00b9\u00b7cm\u207b\u00b9, c = 45 \u00b5M (calcul\u00e9 via la loi de Beer-Lambert)<\/text><rect x=\"226.4\" y=\"90\" width=\"185.6\" height=\"320\" fill=\"#dcfce7\" opacity=\"0.55\"\/><text x=\"319.2\" y=\"84\" text-anchor=\"middle\" font-family=\"Arial,Helvetica,sans-serif\" font-size=\"11\" font-weight=\"700\" fill=\"#15803d\">Fen\u00eatre optimale 0,2\u20131,0<\/text><line x1=\"180\" y1=\"410\" x2=\"760\" y2=\"410\" stroke=\"#233a95\" stroke-width=\"1.5\"\/><line x1=\"180\" y1=\"90\" x2=\"180\" y2=\"410\" stroke=\"#233a95\" stroke-width=\"1.5\"\/><line x1=\"180.0\" y1=\"410\" x2=\"180.0\" y2=\"415\" stroke=\"#233a95\" stroke-width=\"1\"\/><text x=\"180.0\" y=\"430\" text-anchor=\"middle\" font-family=\"Arial,Helvetica,sans-serif\" font-size=\"11\" fill=\"#233a95\">0<\/text><line x1=\"296.0\" y1=\"410\" x2=\"296.0\" y2=\"415\" stroke=\"#233a95\" stroke-width=\"1\"\/><text x=\"296.0\" y=\"430\" text-anchor=\"middle\" font-family=\"Arial,Helvetica,sans-serif\" font-size=\"11\" fill=\"#233a95\">0.5<\/text><line x1=\"412.0\" y1=\"410\" x2=\"412.0\" y2=\"415\" stroke=\"#233a95\" stroke-width=\"1\"\/><text x=\"412.0\" y=\"430\" text-anchor=\"middle\" font-family=\"Arial,Helvetica,sans-serif\" font-size=\"11\" fill=\"#233a95\">1.0<\/text><line x1=\"528.0\" y1=\"410\" x2=\"528.0\" y2=\"415\" stroke=\"#233a95\" stroke-width=\"1\"\/><text x=\"528.0\" y=\"430\" text-anchor=\"middle\" font-family=\"Arial,Helvetica,sans-serif\" font-size=\"11\" fill=\"#233a95\">1.5<\/text><line x1=\"644.0\" y1=\"410\" x2=\"644.0\" y2=\"415\" stroke=\"#233a95\" stroke-width=\"1\"\/><text x=\"644.0\" y=\"430\" text-anchor=\"middle\" font-family=\"Arial,Helvetica,sans-serif\" font-size=\"11\" fill=\"#233a95\">2.0<\/text><line x1=\"760.0\" y1=\"410\" x2=\"760.0\" y2=\"415\" stroke=\"#233a95\" stroke-width=\"1\"\/><text x=\"760.0\" y=\"430\" text-anchor=\"middle\" font-family=\"Arial,Helvetica,sans-serif\" font-size=\"11\" fill=\"#233a95\">2.5<\/text><text x=\"470.0\" y=\"452\" text-anchor=\"middle\" font-family=\"Arial,Helvetica,sans-serif\" font-size=\"12\" font-weight=\"600\" fill=\"#233a95\">Absorbance (A)<\/text><text x=\"35\" y=\"250.0\" text-anchor=\"middle\" font-family=\"Arial,Helvetica,sans-serif\" font-size=\"12\" font-weight=\"600\" fill=\"#233a95\" transform=\"rotate(-90 35 250.0)\">Trajet optique<\/text><text x=\"168\" y=\"120.7\" text-anchor=\"end\" font-family=\"Arial,Helvetica,sans-serif\" font-size=\"13\" font-weight=\"600\" fill=\"#1a2a6c\">1 mm<\/text><rect x=\"180\" y=\"102.7\" width=\"5.8\" height=\"28\" fill=\"#cbd5e1\" stroke=\"#1a2a6c\" stroke-width=\"0.5\" rx=\"2\"\/><text x=\"193.8\" y=\"120.7\" text-anchor=\"start\" font-family=\"Arial,Helvetica,sans-serif\" font-size=\"12\" font-weight=\"600\" fill=\"#1a2a6c\">A = 0.025 \u2022 T = 94.5%<\/text><text x=\"168\" y=\"174.0\" text-anchor=\"end\" font-family=\"Arial,Helvetica,sans-serif\" font-size=\"13\" font-weight=\"600\" fill=\"#1a2a6c\">5 mm<\/text><rect x=\"180\" y=\"156.0\" width=\"28.8\" height=\"28\" fill=\"#86efac\" stroke=\"#1a2a6c\" stroke-width=\"0.5\" rx=\"2\"\/><text x=\"216.8\" y=\"174.0\" text-anchor=\"start\" font-family=\"Arial,Helvetica,sans-serif\" font-size=\"12\" font-weight=\"600\" fill=\"#1a2a6c\">A = 0.124 \u2022 T = 75.2%<\/text><text x=\"168\" y=\"227.3\" text-anchor=\"end\" font-family=\"Arial,Helvetica,sans-serif\" font-size=\"13\" font-weight=\"600\" fill=\"#1a2a6c\">10 mm<\/text><rect x=\"180\" y=\"209.3\" width=\"57.5\" height=\"28\" fill=\"#22c55e\" stroke=\"#1a2a6c\" stroke-width=\"0.5\" rx=\"2\"\/><text x=\"245.5\" y=\"227.3\" text-anchor=\"start\" font-family=\"Arial,Helvetica,sans-serif\" font-size=\"12\" font-weight=\"600\" fill=\"#1a2a6c\">A = 0.248 \u2022 T = 56.6%<\/text><text x=\"168\" y=\"280.7\" text-anchor=\"end\" font-family=\"Arial,Helvetica,sans-serif\" font-size=\"13\" font-weight=\"600\" fill=\"#1a2a6c\">20 mm<\/text><rect x=\"180\" y=\"262.7\" width=\"114.8\" height=\"28\" fill=\"#16a34a\" stroke=\"#1a2a6c\" stroke-width=\"0.5\" rx=\"2\"\/><text x=\"302.8\" y=\"280.7\" text-anchor=\"start\" font-family=\"Arial,Helvetica,sans-serif\" font-size=\"12\" font-weight=\"600\" fill=\"#1a2a6c\">A = 0.495 \u2022 T = 32.0%<\/text><text x=\"168\" y=\"334.0\" text-anchor=\"end\" font-family=\"Arial,Helvetica,sans-serif\" font-size=\"13\" font-weight=\"600\" fill=\"#1a2a6c\">50 mm<\/text><rect x=\"180\" y=\"316.0\" width=\"287.2\" height=\"28\" fill=\"#fb923c\" stroke=\"#1a2a6c\" stroke-width=\"0.5\" rx=\"2\"\/><text x=\"475.2\" y=\"334.0\" text-anchor=\"start\" font-family=\"Arial,Helvetica,sans-serif\" font-size=\"12\" font-weight=\"600\" fill=\"#1a2a6c\">A = 1.238 \u2022 T = 5.78%<\/text><text x=\"168\" y=\"387.3\" text-anchor=\"end\" font-family=\"Arial,Helvetica,sans-serif\" font-size=\"13\" font-weight=\"600\" fill=\"#1a2a6c\">100 mm<\/text><rect x=\"180\" y=\"369.3\" width=\"574.2\" height=\"28\" fill=\"#dc2626\" stroke=\"#1a2a6c\" stroke-width=\"0.5\" rx=\"2\"\/><text x=\"746.2\" y=\"387.3\" text-anchor=\"end\" font-family=\"Arial,Helvetica,sans-serif\" font-size=\"12\" font-weight=\"700\" fill=\"#ffffff\">A = 2.475 \u2022 T = 0.335%<\/text><rect x=\"180\" y=\"468\" width=\"14\" height=\"12\" fill=\"#cbd5e1\"\/><text x=\"200\" y=\"478\" font-family=\"Arial,Helvetica,sans-serif\" font-size=\"11\" fill=\"#333333\">Sous-sensible (A faible)<0.2)<\/text><rect x=\"380\" y=\"468\" width=\"14\" height=\"12\" fill=\"#22c55e\"\/><text x=\"400\" y=\"478\" font-family=\"Arial,Helvetica,sans-serif\" font-size=\"11\" fill=\"#333333\">Optimal (0,2\u20131,0)<\/text><rect x=\"540\" y=\"468\" width=\"14\" height=\"12\" fill=\"#dc2626\"\/><text x=\"560\" y=\"478\" font-family=\"Arial,Helvetica,sans-serif\" font-size=\"11\" fill=\"#333333\">Saturated (A>1.0)<\/text><text x=\"400.0\" y=\"470\" text-anchor=\"middle\" font-family=\"Arial,Helvetica,sans-serif\" font-size=\"11\" font-style=\"italic\" fill=\"#666666\">Valeurs calcul\u00e9es \u00e0 partir du CRC Handbook \u03b5 = 5 500 M\u207b\u00b9\u00b7cm\u207b\u00b9 pour le L-tryptophane libre \u00e0 280 nm. Plage d\u2019absorbance optimale : 0,2\u20131,0.<\/text><\/svg><figcaption style=\"font-size:13px;color:#666;margin-top:12px;font-style:italic;\">Figure : comparaison absorbance vs trajet optique. Tryptophane \u00e0 280 nm, concentration 45 \u00b5M. Calcul\u00e9 via la loi de Beer-Lambert. Plage d\u2019exactitude optimale en vert.<\/figcaption><\/figure>\n\n<div id=\"standard-lengths\">\n<p class=\"csg-label\">Section 3<\/p>\n<h2>Trajets optiques standard et leurs applications principales<\/h2>\n\n<div class=\"csg-path-grid\">\n  <div class=\"csg-path-card\">\n    <div class=\"csg-path-num\">0.1<\/div>\n    <div class=\"csg-path-unit\">mm<\/div>\n    <div class=\"csg-path-desc\">Solutions extr\u00eamement concentr\u00e9es, liquides purs, \u00e9tat solide<\/div>\n  <\/div>\n  <div class=\"csg-path-card\">\n    <div class=\"csg-path-num\">0.2<\/div>\n    <div class=\"csg-path-unit\">mm<\/div>\n    <div class=\"csg-path-desc\">Prot\u00e9ine, acide nucl\u00e9ique, pharmaceutique \u00e0 forte concentration<\/div>\n  <\/div>\n  <div class=\"csg-path-card\">\n    <div class=\"csg-path-num\">0.5<\/div>\n    <div class=\"csg-path-unit\">mm<\/div>\n    <div class=\"csg-path-desc\">Solutions d\u2019API concentr\u00e9es, \u00e9chantillons de plasma non dilu\u00e9s<\/div>\n  <\/div>\n  <div class=\"csg-path-card\">\n    <div class=\"csg-path-num\">1<\/div>\n    <div class=\"csg-path-unit\">mm<\/div>\n    <div class=\"csg-path-desc\">Le court trajet le plus courant \u2014 prot\u00e9ines denses, huiles, colorants concentr\u00e9s<\/div>\n  <\/div>\n  <div class=\"csg-path-card\">\n    <div class=\"csg-path-num\">2<\/div>\n    <div class=\"csg-path-unit\">mm<\/div>\n    <div class=\"csg-path-desc\">\u00c9chantillons mod\u00e9r\u00e9ment concentr\u00e9s, dosages d\u00e9riv\u00e9s du sang<\/div>\n  <\/div>\n  <div class=\"csg-path-card\">\n    <div class=\"csg-path-num\">5<\/div>\n    <div class=\"csg-path-unit\">mm<\/div>\n    <div class=\"csg-path-desc\">Semi-concentr\u00e9, r\u00e9duit le volume vs 10 mm en cuves \u00e9troites<\/div>\n  <\/div>\n  <div class=\"csg-path-card\">\n    <div class=\"csg-path-num\">10<\/div>\n    <div class=\"csg-path-unit\">mm<\/div>\n    <div class=\"csg-path-desc\"><strong>Standard.<\/strong> Dilutions aqueuses, quantification prot\u00e9ine\/ADN, UV-Vis g\u00e9n\u00e9ral<\/div>\n  <\/div>\n  <div class=\"csg-path-card\">\n    <div class=\"csg-path-num\">20<\/div>\n    <div class=\"csg-path-unit\">mm<\/div>\n    <div class=\"csg-path-desc\">\u00c9chantillons dilu\u00e9s n\u00e9cessitant 2\u00d7 la sensibilit\u00e9 du standard<\/div>\n  <\/div>\n  <div class=\"csg-path-card\">\n    <div class=\"csg-path-num\">30<\/div>\n    <div class=\"csg-path-unit\">mm<\/div>\n    <div class=\"csg-path-desc\">Analyse d\u2019eau environnementale, flux industriels dilu\u00e9s<\/div>\n  <\/div>\n  <div class=\"csg-path-card\">\n    <div class=\"csg-path-num\">50<\/div>\n    <div class=\"csg-path-unit\">mm<\/div>\n    <div class=\"csg-path-desc\">D\u00e9tection de contaminants traces, normes d\u2019eau potable<\/div>\n  <\/div>\n  <div class=\"csg-path-card\">\n    <div class=\"csg-path-num\">100<\/div>\n    <div class=\"csg-path-unit\">mm<\/div>\n    <div class=\"csg-path-desc\">Le long trajet le plus courant \u2014 eaux us\u00e9es, couleur, m\u00e9taux traces<\/div>\n  <\/div>\n  <div class=\"csg-path-card\">\n    <div class=\"csg-path-num\">200<\/div>\n    <div class=\"csg-path-unit\">mm<\/div>\n    <div class=\"csg-path-desc\">Analyse ultra-trace, applications de plus haute sensibilit\u00e9<\/div>\n  <\/div>\n<\/div>\n\n<div class=\"csg-table-wrap\">\n  <table class=\"csg-table\">\n    <thead>\n      <tr>\n        <th>Trajet optique<\/th>\n        <th>Volume (macro standard)<\/th>\n        <th>Application typique<\/th>\n        <th>Sensibilit\u00e9 relative vs 10 mm<\/th>\n      <\/tr>\n    <\/thead>\n    <tbody>\n      <tr>\n        <td>0,1 mm<\/td>\n        <td>~0,035 mL<\/td>\n        <td>Solvants purs, solutions de polym\u00e8res concentr\u00e9es<\/td>\n        <td><span class=\"csg-badge csg-badge-orange\">1\/100\u00d7<\/span><\/td>\n      <\/tr>\n      <tr>\n        <td>0,5 mm<\/td>\n        <td>~0,18 mL<\/td>\n        <td>Formulations de prot\u00e9ines concentr\u00e9es, plasma<\/td>\n        <td><span class=\"csg-badge csg-badge-orange\">1\/20\u00d7<\/span><\/td>\n      <\/tr>\n      <tr>\n        <td>1 mm<\/td>\n        <td>~0,35 mL<\/td>\n        <td>Concentrated dyes, protein solutions >5 mg\/mL<\/td>\n        <td><span class=\"csg-badge csg-badge-orange\">1\/10\u00d7<\/span><\/td>\n      <\/tr>\n      <tr>\n        <td>2 mm<\/td>\n        <td>~0,7 mL<\/td>\n        <td>\u00c9chantillons mod\u00e9r\u00e9ment concentr\u00e9s, dilution r\u00e9duite<\/td>\n        <td><span class=\"csg-badge csg-badge-orange\">1\/5\u00d7<\/span><\/td>\n      <\/tr>\n      <tr>\n        <td>5 mm<\/td>\n        <td>~1,75 mL<\/td>\n        <td>Semi-concentr\u00e9, applications de milieu de gamme<\/td>\n        <td><span class=\"csg-badge csg-badge-blue\">1\/2\u00d7<\/span><\/td>\n      <\/tr>\n      <tr>\n        <td>10 mm<\/td>\n        <td>3,5 mL<\/td>\n        <td>Standard \u2014 UV-Vis g\u00e9n\u00e9ral, prot\u00e9ine\/ADN, la plupart des dosages<\/td>\n        <td><span class=\"csg-badge csg-badge-green\">1\u00d7 (r\u00e9f\u00e9rence)<\/span><\/td>\n      <\/tr>\n      <tr>\n        <td>20 mm<\/td>\n        <td>7 mL<\/td>\n        <td>\u00c9chantillons dilu\u00e9s, plage lin\u00e9aire \u00e9tendue<\/td>\n        <td><span class=\"csg-badge csg-badge-green\">2\u00d7<\/span><\/td>\n      <\/tr>\n      <tr>\n        <td>50 mm<\/td>\n        <td>17,5 mL<\/td>\n        <td>Analyse de traces environnementales, eau potable<\/td>\n        <td><span class=\"csg-badge csg-badge-green\">5\u00d7<\/span><\/td>\n      <\/tr>\n      <tr>\n        <td>100 mm<\/td>\n        <td>35 mL<\/td>\n        <td>Eaux us\u00e9es, mesure de couleur, contamination trace<\/td>\n        <td><span class=\"csg-badge csg-badge-green\">10\u00d7<\/span><\/td>\n      <\/tr>\n      <tr>\n        <td>200 mm<\/td>\n        <td>70 mL<\/td>\n        <td>Ultra-trace, d\u00e9tection au niveau du ppb<\/td>\n        <td><span class=\"csg-badge csg-badge-green\">20\u00d7<\/span><\/td>\n      <\/tr>\n    <\/tbody>\n  <\/table>\n<\/div>\n\n<!-- SVG 3: Short vs Standard vs Long path comparison -->\n<div style=\"background:#f7f8fc;border-radius:12px;padding:20px 16px 14px;margin:24px 0;\">\n<svg viewBox=\"0 0 700 230\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" style=\"width:100%;max-width:700px;display:block;margin:0 auto;\" aria-label=\"Comparaison c\u00f4te \u00e0 c\u00f4te de cuves court trajet 1 mm, standard 10 mm et long trajet 100 mm\">\n  <rect width=\"700\" height=\"230\" fill=\"#f7f8fc\" rx=\"8\"\/>\n  <text x=\"350\" y=\"18\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"12.5\" font-weight=\"700\" fill=\"#233a95\" letter-spacing=\"1\">COURT \u00b7 STANDARD \u00b7 LONG TRAJET \u2014 C\u00d4TE \u00c0 C\u00d4TE<\/text>\n\n  <!-- === SHORT PATH 1mm === -->\n  <g transform=\"translate(60,32)\">\n    <!-- Outer cuvette -->\n    <rect x=\"0\" y=\"0\" width=\"130\" height=\"130\" rx=\"4\" fill=\"none\" stroke=\"#8b3fc8\" stroke-width=\"2\"\/>\n    <!-- Left wall (thick \u2014 proportionally shown) -->\n    <rect x=\"0\" y=\"0\" width=\"28\" height=\"130\" fill=\"rgba(167,139,250,0.3)\" stroke=\"#8b3fc8\" stroke-width=\"1.2\"\/>\n    <!-- Right wall -->\n    <rect x=\"102\" y=\"0\" width=\"28\" height=\"130\" fill=\"rgba(167,139,250,0.3)\" stroke=\"#8b3fc8\" stroke-width=\"1.2\"\/>\n    <!-- Sample (narrow) -->\n    <rect x=\"28\" y=\"0\" width=\"74\" height=\"130\" fill=\"rgba(120,60,200,0.28)\"\/>\n    <!-- Path length arrow -->\n    <line x1=\"28\" y1=\"148\" x2=\"102\" y2=\"148\" stroke=\"#8b3fc8\" stroke-width=\"1.5\"\/>\n    <polygon points=\"28,144 28,152 20,148\" fill=\"#8b3fc8\"\/>\n    <polygon points=\"102,144 102,152 110,148\" fill=\"#8b3fc8\"\/>\n    <text x=\"65\" y=\"163\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"11.5\" font-weight=\"700\" fill=\"#8b3fc8\">1 mm<\/text>\n    <!-- Label -->\n    <text x=\"65\" y=\"185\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"11\" fill=\"#6b21a8\" font-weight=\"700\">COURT TRAJET<\/text>\n    <text x=\"65\" y=\"198\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"10\" fill=\"#6b21a8\">\u00c9chantillons concentr\u00e9s<\/text>\n    <text x=\"65\" y=\"210\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"10\" fill=\"#6b21a8\">A > au-dessus de 1,5 en 10 mm<\/text>\n    <!-- Light beam -->\n    <defs><marker id=\"sp1\" markerWidth=\"6\" markerHeight=\"5\" refX=\"6\" refY=\"2.5\" orient=\"auto\"><polygon points=\"0,0 6,2.5 0,5\" fill=\"#f59e0b\"\/><\/marker><\/defs>\n    <line x1=\"-42\" y1=\"65\" x2=\"-3\" y2=\"65\" stroke=\"#f59e0b\" stroke-width=\"2.5\" marker-end=\"url(#sp1)\"\/>\n    <defs><marker id=\"sp2\" markerWidth=\"6\" markerHeight=\"5\" refX=\"6\" refY=\"2.5\" orient=\"auto\"><polygon points=\"0,0 6,2.5 0,5\" fill=\"#dc2626\"\/><\/marker><\/defs>\n    <line x1=\"133\" y1=\"65\" x2=\"170\" y2=\"65\" stroke=\"#dc2626\" stroke-width=\"1.6\" marker-end=\"url(#sp2)\"\/>\n    <!-- sample label -->\n    <text x=\"65\" y=\"62\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"10\" fill=\"rgba(255,255,255,0.8)\" font-weight=\"600\">dense<\/text>\n    <text x=\"65\" y=\"74\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"10\" fill=\"rgba(255,255,255,0.8)\">\u00e9chantillon<\/text>\n  <\/g>\n\n  <!-- === STANDARD 10mm === -->\n  <g transform=\"translate(268,32)\">\n    <rect x=\"0\" y=\"0\" width=\"165\" height=\"130\" rx=\"4\" fill=\"none\" stroke=\"#233a95\" stroke-width=\"2.5\"\/>\n    <rect x=\"0\" y=\"0\" width=\"22\" height=\"130\" fill=\"rgba(147,197,253,0.35)\" stroke=\"#233a95\" stroke-width=\"1.2\"\/>\n    <rect x=\"143\" y=\"0\" width=\"22\" height=\"130\" fill=\"rgba(147,197,253,0.35)\" stroke=\"#233a95\" stroke-width=\"1.2\"\/>\n    <rect x=\"22\" y=\"0\" width=\"121\" height=\"130\" fill=\"rgba(59,130,246,0.12)\"\/>\n    <line x1=\"22\" y1=\"148\" x2=\"143\" y2=\"148\" stroke=\"#233a95\" stroke-width=\"1.5\"\/>\n    <polygon points=\"22,144 22,152 14,148\" fill=\"#233a95\"\/>\n    <polygon points=\"143,144 143,152 151,148\" fill=\"#233a95\"\/>\n    <text x=\"82\" y=\"163\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"11.5\" font-weight=\"700\" fill=\"#233a95\">10 mm<\/text>\n    <text x=\"82\" y=\"185\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"11\" fill=\"#233a95\" font-weight=\"700\">STANDARD \u2605<\/text>\n    <text x=\"82\" y=\"198\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"10\" fill=\"#233a95\">La plupart des applications UV-Vis<\/text>\n    <text x=\"82\" y=\"210\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"10\" fill=\"#233a95\">R\u00e9f\u00e9rence de base<\/text>\n    <defs><marker id=\"mp1\" markerWidth=\"6\" markerHeight=\"5\" refX=\"6\" refY=\"2.5\" orient=\"auto\"><polygon points=\"0,0 6,2.5 0,5\" fill=\"#f59e0b\"\/><\/marker><\/defs>\n    <line x1=\"-38\" y1=\"65\" x2=\"-3\" y2=\"65\" stroke=\"#f59e0b\" stroke-width=\"2.5\" marker-end=\"url(#mp1)\"\/>\n    <defs><marker id=\"mp2\" markerWidth=\"6\" markerHeight=\"5\" refX=\"6\" refY=\"2.5\" orient=\"auto\"><polygon points=\"0,0 6,2.5 0,5\" fill=\"#dc2626\"\/><\/marker><\/defs>\n    <line x1=\"168\" y1=\"65\" x2=\"203\" y2=\"65\" stroke=\"#dc2626\" stroke-width=\"2\" marker-end=\"url(#mp2)\"\/>\n    <text x=\"82\" y=\"62\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"10\" fill=\"rgba(59,130,246,0.8)\" font-weight=\"600\">dilu\u00e9<\/text>\n    <text x=\"82\" y=\"74\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"10\" fill=\"rgba(59,130,246,0.8)\">aqueux<\/text>\n  <\/g>\n\n  <!-- === LONG PATH 100mm === -->\n  <g transform=\"translate(510,32)\">\n    <!-- Horizontal long cuvette (rotated to show wide internal chamber) -->\n    <rect x=\"0\" y=\"20\" width=\"170\" height=\"90\" rx=\"4\" fill=\"none\" stroke=\"#166534\" stroke-width=\"2\"\/>\n    <rect x=\"0\" y=\"20\" width=\"16\" height=\"90\" fill=\"rgba(134,239,172,0.35)\" stroke=\"#166534\" stroke-width=\"1.2\"\/>\n    <rect x=\"154\" y=\"20\" width=\"16\" height=\"90\" fill=\"rgba(134,239,172,0.35)\" stroke=\"#166534\" stroke-width=\"1.2\"\/>\n    <rect x=\"16\" y=\"20\" width=\"138\" height=\"90\" fill=\"rgba(34,197,94,0.08)\"\/>\n    <line x1=\"16\" y1=\"148\" x2=\"154\" y2=\"148\" stroke=\"#166534\" stroke-width=\"1.5\"\/>\n    <polygon points=\"16,144 16,152 8,148\" fill=\"#166534\"\/>\n    <polygon points=\"154,144 154,152 162,148\" fill=\"#166534\"\/>\n    <text x=\"85\" y=\"163\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"11.5\" font-weight=\"700\" fill=\"#166534\">100 mm<\/text>\n    <text x=\"85\" y=\"185\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"11\" fill=\"#166534\" font-weight=\"700\">LONG TRAJET<\/text>\n    <text x=\"85\" y=\"198\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"10\" fill=\"#166534\">Analyse de traces \/ env.<\/text>\n    <text x=\"85\" y=\"210\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"10\" fill=\"#166534\">A < 0.05 in 10mm<\/text>\n    <defs><marker id=\"lp1\" markerWidth=\"6\" markerHeight=\"5\" refX=\"6\" refY=\"2.5\" orient=\"auto\"><polygon points=\"0,0 6,2.5 0,5\" fill=\"#f59e0b\"\/><\/marker><\/defs>\n    <line x1=\"-26\" y1=\"65\" x2=\"-3\" y2=\"65\" stroke=\"#f59e0b\" stroke-width=\"2.5\" marker-end=\"url(#lp1)\"\/>\n    <defs><marker id=\"lp2\" markerWidth=\"6\" markerHeight=\"5\" refX=\"6\" refY=\"2.5\" orient=\"auto\"><polygon points=\"0,0 6,2.5 0,5\" fill=\"#15803d\"\/><\/marker><\/defs>\n    <line x1=\"157\" y1=\"65\" x2=\"180\" y2=\"65\" stroke=\"#15803d\" stroke-width=\"2.2\" marker-end=\"url(#lp2)\"\/>\n    <!-- dashed beam inside -->\n    <line x1=\"16\" y1=\"65\" x2=\"154\" y2=\"65\" stroke=\"#f59e0b\" stroke-width=\"1.5\" stroke-dasharray=\"6,4\" opacity=\"0.5\"\/>\n    <text x=\"85\" y=\"57\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"10\" fill=\"rgba(34,197,94,0.8)\">tr\u00e8s dilu\u00e9<\/text>\n    <text x=\"85\" y=\"69\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"10\" fill=\"rgba(34,197,94,0.8)\">\u00e9chantillon<\/text>\n  <\/g>\n\n<\/svg>\n<p style=\"text-align:center;font-size:12px;color:#888;margin:6px 0 0;\">De gauche \u00e0 droite : court trajet de 1 mm (chambre \u00e9troite, \u00e9chantillon dense), standard de 10 mm (la plupart du travail UV-Vis), long trajet de 100 mm (chambre large, analyte trace). Les fl\u00e8ches de trajet optique montrent la dimension <em>l<\/em> de Beer-Lambert.<\/p>\n<\/div>\n<\/div>\n\n<div id=\"how-to-choose\">\n<p class=\"csg-label\">Section 4<\/p>\n<h2>Comment choisir le bon trajet optique<\/h2>\n\n<div class=\"csg-decision\">\n  <h3>Cadre de s\u00e9lection pas \u00e0 pas<\/h3>\n  <div class=\"csg-decision-step\">\n    <div class=\"csg-decision-num\">1<\/div>\n    <div class=\"csg-decision-text\"><strong>Identifiez l\u2019absorptivit\u00e9 molaire (\u03b5) de votre analyte \u00e0 la longueur d\u2019onde de mesure.<\/strong> C\u2019est une propri\u00e9t\u00e9 fixe de la mol\u00e9cule \u2014 cherchez-la dans la litt\u00e9rature ou la m\u00e9thode de votre instrument. Valeurs courantes : BSA \u00e0 280 nm \u2248 43 824 L mol\u207b\u00b9 cm\u207b\u00b9 ; NADH \u00e0 340 nm \u2248 6 220 L mol\u207b\u00b9 cm\u207b\u00b9.<\/div>\n  <\/div>\n  <div class=\"csg-decision-step\">\n    <div class=\"csg-decision-num\">2<\/div>\n    <div class=\"csg-decision-text\"><strong>Connaissez votre plage de concentration d\u2019\u00e9chantillon.<\/strong> Si vous ne pouvez pas diluer (volume d\u2019\u00e9chantillon limit\u00e9, mati\u00e8re pr\u00e9cieuse) ni concentrer (\u00e9chantillon environnemental dilu\u00e9), cela contraint votre choix de trajet optique.<\/div>\n  <\/div>\n  <div class=\"csg-decision-step\">\n    <div class=\"csg-decision-num\">3<\/div>\n    <div class=\"csg-decision-text\"><strong>Calculez l\u2019absorbance attendue \u00e0 10 mm.<\/strong> Use A = \u03b5 \u00d7 c \u00d7 l (with l = 1 cm). If A is in the range 0.1\u20131.0, the 10 mm standard cuvette is correct. If A > Si A est sup\u00e9rieure \u00e0 environ 1,5, utilisez un trajet plus court. Si A est inf\u00e9rieure \u00e0 0,1, utilisez un trajet plus long. < 0.05, use a longer path.<\/div>\n  <\/div>\n  <div class=\"csg-decision-step\">\n    <div class=\"csg-decision-num\">4<\/div>\n    <div class=\"csg-decision-text\"><strong>Mettez le trajet optique \u00e0 l\u2019\u00e9chelle pour ramener A dans la plage.<\/strong> Trajet optique cible (mm) = 10 mm \u00d7 (A cible \/ A calcul\u00e9e \u00e0 10 mm). Arrondissez au trajet optique standard disponible le plus proche.<\/div>\n  <\/div>\n  <div class=\"csg-decision-step\">\n    <div class=\"csg-decision-num\">5<\/div>\n    <div class=\"csg-decision-text\"><strong>V\u00e9rifiez le volume d\u2019\u00e9chantillon.<\/strong> Les cuves \u00e0 court trajet ont de plus petits volumes internes \u2014 une cuve macro de 1 mm contient ~0,35 mL. Si votre \u00e9chantillon est limit\u00e9, c\u2019est un avantage. Si vous avez besoin d\u2019un grand volume (p. ex. pour collecte de fractions), une cuve \u00e0 long trajet peut ne pas convenir aux formats micro.<\/div>\n  <\/div>\n<\/div>\n\n<div class=\"csg-tool-box\">\n  <div class=\"csg-tool-icon\">\ud83e\uddee<\/div>\n  <div class=\"csg-tool-text\">\n    <h4>Utilisez le calculateur de trajet optique<\/h4>\n    <p>Saisissez l\u2019absorptivit\u00e9 molaire de votre analyte, la concentration de l\u2019\u00e9chantillon et l\u2019absorbance cible \u2014 le calculateur recommande le trajet optimal et montre le calcul de Beer-Lambert.<\/p>\n    <a href=\"https:\/\/machinedquartz.com\/path-length-calculator\/\">Ouvrir le calculateur de trajet optique \u2192<\/a>\n  <\/div>\n<\/div>\n<\/div>\n\n<div id=\"short-path\">\n<p class=\"csg-label\">Section 5<\/p>\n<h2>Cuves \u00e0 court trajet (sous 10 mm)<10 mm)<\/h2>\n\n<!-- SVG: Short path length diagram -->\n<div style=\"background:#f7f8fc;border-radius:12px;padding:24px 20px 16px;margin:0 0 28px;\">\n<svg viewBox=\"0 0 700 220\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" style=\"width:100%;max-width:700px;display:block;margin:0 auto;\" aria-label=\"Sch\u00e9ma de cuve \u00e0 court trajet montrant l'\u00e9cart interne \u00e9troit de 1 mm et un \u00e9chantillon concentr\u00e9\">\n\n  <!-- Background -->\n  <rect width=\"700\" height=\"220\" fill=\"#f7f8fc\" rx=\"10\"\/>\n\n  <!-- Title -->\n  <text x=\"350\" y=\"22\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"13\" font-weight=\"700\" fill=\"#233a95\" letter-spacing=\"1\">CUVE \u00c0 COURT TRAJET \u2014 exemple 1 mm<\/text>\n\n  <!-- \u2500\u2500 Cuvette body \u2500\u2500 -->\n  <!-- Outer walls (quartz, semi-transparent) -->\n  <rect x=\"290\" y=\"38\" width=\"120\" height=\"150\" rx=\"4\" fill=\"rgba(200,220,255,0.18)\" stroke=\"#233a95\" stroke-width=\"2.5\"\/>\n  <!-- Left wall (thick quartz) -->\n  <rect x=\"290\" y=\"38\" width=\"26\" height=\"150\" rx=\"3\" fill=\"rgba(180,200,240,0.45)\" stroke=\"#233a95\" stroke-width=\"1.5\"\/>\n  <!-- Right wall (thick quartz) -->\n  <rect x=\"384\" y=\"38\" width=\"26\" height=\"150\" rx=\"3\" fill=\"rgba(180,200,240,0.45)\" stroke=\"#233a95\" stroke-width=\"1.5\"\/>\n  <!-- Sample chamber (narrow 1mm gap, shown proportionally wide for clarity) -->\n  <rect x=\"316\" y=\"38\" width=\"68\" height=\"150\" fill=\"rgba(120,60,200,0.22)\" stroke=\"#8b3fc8\" stroke-width=\"1.5\" stroke-dasharray=\"4,3\"\/>\n\n  <!-- Sample label inside chamber -->\n  <text x=\"350\" y=\"108\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"11\" fill=\"#6b21a8\" font-weight=\"700\">FORTE<\/text>\n  <text x=\"350\" y=\"122\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"11\" fill=\"#6b21a8\" font-weight=\"700\">CONC.<\/text>\n  <text x=\"350\" y=\"136\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"10\" fill=\"#6b21a8\">\u00e9chantillon<\/text>\n\n  <!-- Path length double arrow -->\n  <line x1=\"316\" y1=\"188\" x2=\"384\" y2=\"188\" stroke=\"#233a95\" stroke-width=\"1.8\"\/>\n  <polygon points=\"316,184 316,192 308,188\" fill=\"#233a95\"\/>\n  <polygon points=\"384,184 384,192 392,188\" fill=\"#233a95\"\/>\n  <text x=\"350\" y=\"204\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"11.5\" font-weight=\"700\" fill=\"#233a95\">trajet 1 mm<\/text>\n\n  <!-- Light beam LEFT \u2192 entering -->\n  <defs>\n    <marker id=\"arrowR1\" markerWidth=\"8\" markerHeight=\"6\" refX=\"8\" refY=\"3\" orient=\"auto\">\n      <polygon points=\"0,0 8,3 0,6\" fill=\"#f59e0b\"\/>\n    <\/marker>\n  <\/defs>\n  <!-- Beam rays entering left -->\n  <line x1=\"50\" y1=\"113\" x2=\"288\" y2=\"113\" stroke=\"#f59e0b\" stroke-width=\"3\" marker-end=\"url(#arrowR1)\" opacity=\"0.9\"\/>\n  <line x1=\"50\" y1=\"100\" x2=\"288\" y2=\"100\" stroke=\"#f59e0b\" stroke-width=\"1.5\" opacity=\"0.5\"\/>\n  <line x1=\"50\" y1=\"126\" x2=\"288\" y2=\"126\" stroke=\"#f59e0b\" stroke-width=\"1.5\" opacity=\"0.5\"\/>\n  <text x=\"168\" y=\"90\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"12\" fill=\"#b45309\" font-weight=\"600\">Lumi\u00e8re incidente<\/text>\n\n  <!-- Beam rays exiting right (attenuated - thinner\/darker) -->\n  <defs>\n    <marker id=\"arrowR2\" markerWidth=\"8\" markerHeight=\"6\" refX=\"8\" refY=\"3\" orient=\"auto\">\n      <polygon points=\"0,0 8,3 0,6\" fill=\"#dc2626\"\/>\n    <\/marker>\n  <\/defs>\n  <line x1=\"412\" y1=\"113\" x2=\"620\" y2=\"113\" stroke=\"#dc2626\" stroke-width=\"2\" marker-end=\"url(#arrowR2)\" opacity=\"0.85\"\/>\n  <line x1=\"412\" y1=\"100\" x2=\"620\" y2=\"100\" stroke=\"#dc2626\" stroke-width=\"0.8\" opacity=\"0.4\"\/>\n  <line x1=\"412\" y1=\"126\" x2=\"620\" y2=\"126\" stroke=\"#dc2626\" stroke-width=\"0.8\" opacity=\"0.4\"\/>\n  <text x=\"516\" y=\"90\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"12\" fill=\"#991b1b\" font-weight=\"600\">Lumi\u00e8re transmise<\/text>\n\n  <!-- LEFT wall label -->\n  <text x=\"303\" y=\"30\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"10\" fill=\"#4b5563\">Paroi<\/text>\n  <text x=\"303\" y=\"41\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"10\" fill=\"#4b5563\">en quartz<\/text>\n\n  <!-- Right wall label -->\n  <text x=\"397\" y=\"30\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"10\" fill=\"#4b5563\">Paroi<\/text>\n  <text x=\"397\" y=\"41\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"10\" fill=\"#4b5563\">en quartz<\/text>\n\n  <!-- Absorbance note -->\n  <rect x=\"500\" y=\"148\" width=\"168\" height=\"38\" rx=\"6\" fill=\"#fef3c7\" stroke=\"#f59e0b\" stroke-width=\"1.2\"\/>\n  <text x=\"584\" y=\"163\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"11\" fill=\"#92400e\" font-weight=\"700\">Court trajet = A faible<\/text>\n  <text x=\"584\" y=\"178\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"10.5\" fill=\"#92400e\">m\u00eame pour des \u00e9chantillons denses<\/text>\n\n  <!-- Concentration note -->\n  <rect x=\"32\" y=\"148\" width=\"168\" height=\"38\" rx=\"6\" fill=\"#ede9fe\" stroke=\"#8b3fc8\" stroke-width=\"1.2\"\/>\n  <text x=\"116\" y=\"163\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"11\" fill=\"#6b21a8\" font-weight=\"700\">Use when: A > 1.5<\/text>\n  <text x=\"116\" y=\"178\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"10.5\" fill=\"#6b21a8\">dans <a href=\"https:\/\/machinedquartz.com\/cuvettes-and-cells-size-chart\/\">une cuve de 10 mm<\/a><\/text>\n\n<\/svg>\n<p style=\"text-align:center;font-size:12px;color:#888;margin:8px 0 0;\">Cuve \u00e0 court trajet (1 mm montr\u00e9) : la chambre d\u2019\u00e9chantillon \u00e9troite r\u00e9duit le trajet de Beer-Lambert effectif, ramenant les \u00e9chantillons \u00e0 forte absorbance dans la plage mesurable.<\/p>\n<\/div>\n\n<p>Les cuves \u00e0 court trajet (0,1\u20135 mm) servent quand les \u00e9chantillons ont une forte absorbance \u00e0 la longueur d\u2019onde de mesure et ne peuvent ou ne doivent pas \u00eatre dilu\u00e9s. Situations courantes :<\/p>\n\n<div class=\"csg-card-grid-2\">\n  <div class=\"csg-card\">\n    <div class=\"csg-card-icon\">\ud83e\uddec<\/div>\n    <h3>Prot\u00e9ines tr\u00e8s concentr\u00e9es<\/h3>\n    <p>Formulations d\u2019anticorps monoclonaux \u00e0 10\u201350 mg\/mL, solutions m\u00e8res de BSA concentr\u00e9es, prot\u00e9ines th\u00e9rapeutiques mesur\u00e9es \u00e0 280 nm. Une solution de prot\u00e9ine \u00e0 1 mg\/mL lit typiquement ~0,7 A \u00e0 280 nm dans une cuve de 10 mm \u2014 \u00e0 10 mg\/mL cela devient 7 A, bien hors de la plage lin\u00e9aire. Une cuve de 1 mm le ram\u00e8ne \u00e0 0,7 A.<\/p>\n  <\/div>\n  <div class=\"csg-card\">\n    <div class=\"csg-card-icon\">\ud83d\udc8a<\/div>\n    <h3>Formulations pharmaceutiques<\/h3>\n    <p>Les principes actifs (API) sont souvent mesur\u00e9s non dilu\u00e9s ou \u00e0 forte concentration en d\u00e9veloppement de formulation. Les cuves \u00e0 court trajet (0,5\u20132 mm) permettent une mesure directe sans les erreurs de dilution qui peuvent affecter l\u2019exactitude.<\/p>\n  <\/div>\n  <div class=\"csg-card\">\n    <div class=\"csg-card-icon\">\ud83d\udee2\ufe0f<\/div>\n    <h3>Liquides purs et huiles<\/h3>\n    <p>Mesurer l\u2019absorption de solvants purs, huiles, solutions de polym\u00e8res ou m\u00e9langes r\u00e9actionnels de synth\u00e8se organique n\u00e9cessite souvent des trajets de 0,1\u20131 mm, car les absorptivit\u00e9s molaires et les concentrations se combinent pour produire des absorbances de plusieurs centaines sans r\u00e9duction de trajet.<\/p>\n  <\/div>\n  <div class=\"csg-card\">\n    <div class=\"csg-card-icon\">\ud83e\ude78<\/div>\n    <h3>Matrices biologiques<\/h3>\n    <p>Le sang total, le plasma et le s\u00e9rum contiennent de fortes concentrations de multiples esp\u00e8ces absorbantes. Les cuves \u00e0 court trajet (0,5\u20132 mm) permettent une mesure directe et r\u00e9duisent l\u2019interf\u00e9rence des effets de matrice par rapport aux aliquots dilu\u00e9s.<\/p>\n  <\/div>\n<\/div>\n\n<h3>Cuve 1 mm : le court trajet le plus courant<\/h3>\n\n<p>La <strong>cuve de 1 mm<\/strong> (trajet optique 1 mm, Beer-Lambert l <em>l<\/em> = 0,1 cm) est la cuve \u00e0 court trajet la plus utilis\u00e9e. Elle d\u00e9livre exactement 1\/10 de l\u2019absorbance d\u2019une cuve de 10 mm pour le m\u00eame \u00e9chantillon, ce qui la rend id\u00e9ale pour toute solution qui lirait au-dessus de 1,5 A dans une cuve standard. Une cuve de 1 mm a typiquement un volume interne de ~0,35 mL en format macro, ou ~70\u2013100 \u00b5L en format semi-micro.<\/p>\n\n<p>Common uses for a 1mm cuvette: concentrated monoclonal antibody formulations (>Usages courants de la cuve de 1 mm : prot\u00e9ines concentr\u00e9es (au-dessus de 5 mg\/mL), mesures de substance m\u00e9dicamenteuse prot\u00e9ique \u00e0 280 nm, solutions de colorant concentr\u00e9es en CQ industriel, solvants organiques purs, et suivi de r\u00e9action \u00e0 forte concentration d\u2019analyte. Nos cuves de 1 mm sont parmi les articles les plus critiques en pr\u00e9cision que nous fabriquons \u2014 tenir un \u00e9cart interne de 1 mm \u00e0 \u00b10,02 mm de tol\u00e9rance exige un montage plus serr\u00e9 qu\u2019une cuve standard de 10 mm. Les cuves de 1 mm MachinedQuartz existent en macro standard (ext\u00e9rieur 10\u00d710 mm), volume r\u00e9duit et configurations de cuve \u00e0 circulation.<\/p>\n\n<div class=\"csg-warning\">\n  <strong>Note de nettoyage :<\/strong> Les cuves \u00e0 court trajet sont plus difficiles \u00e0 nettoyer que les cuves standard car l\u2019\u00e9cart interne \u00e9troit rend le rin\u00e7age et le s\u00e9chage plus difficiles. Utilisez une seringue pour faire passer le solvant \u00e0 r\u00e9p\u00e9tition. N\u2019utilisez pas de brosses \u00e0 cuve \u2014 elles rayent les fen\u00eatres optiques. Le s\u00e9chage \u00e0 l\u2019air comprim\u00e9 ou \u00e0 l\u2019azote est recommand\u00e9.\n<\/div>\n<\/div>\n\n<div id=\"long-path\">\n<p class=\"csg-label\">Section 6<\/p>\n<h2>Long Path Length Cuvettes (>10 mm)<\/h2>\n\n<!-- SVG: Long path length diagram -->\n<div style=\"background:#f0f7f0;border-radius:12px;padding:24px 20px 16px;margin:0 0 28px;\">\n<svg viewBox=\"0 0 700 240\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" style=\"width:100%;max-width:700px;display:block;margin:0 auto;\" aria-label=\"Sch\u00e9ma de cuve \u00e0 long trajet montrant la large chambre interne de 100 mm et un \u00e9chantillon dilu\u00e9\">\n\n  <!-- Background -->\n  <rect width=\"700\" height=\"240\" fill=\"#f0f7f0\" rx=\"10\"\/>\n\n  <!-- Title -->\n  <text x=\"350\" y=\"22\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"13\" font-weight=\"700\" fill=\"#166534\" letter-spacing=\"1\">CUVE \u00c0 LONG TRAJET \u2014 exemple 100 mm<\/text>\n\n  <!-- \u2500\u2500 Cuvette body \u2014 wide horizontal cuvette \u2500\u2500 -->\n  <!-- Outer frame -->\n  <rect x=\"80\" y=\"58\" width=\"540\" height=\"120\" rx=\"5\" fill=\"rgba(200,240,210,0.2)\" stroke=\"#166534\" stroke-width=\"2.5\"\/>\n  <!-- Left wall -->\n  <rect x=\"80\" y=\"58\" width=\"22\" height=\"120\" rx=\"3\" fill=\"rgba(180,230,190,0.55)\" stroke=\"#166534\" stroke-width=\"1.5\"\/>\n  <!-- Right wall -->\n  <rect x=\"598\" y=\"58\" width=\"22\" height=\"120\" rx=\"3\" fill=\"rgba(180,230,190,0.55)\" stroke=\"#166534\" stroke-width=\"1.5\"\/>\n  <!-- Sample chamber (wide, dilute \u2014 pale tint) -->\n  <rect x=\"102\" y=\"58\" width=\"496\" height=\"120\" fill=\"rgba(34,197,94,0.08)\" stroke=\"#16a34a\" stroke-width=\"1.2\" stroke-dasharray=\"5,4\"\/>\n\n  <!-- Dilute sample label -->\n  <text x=\"350\" y=\"108\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"12\" fill=\"#166534\" font-weight=\"700\">\u00c9CHANTILLON DILU\u00c9<\/text>\n  <text x=\"350\" y=\"124\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"11\" fill=\"#166534\">(analyte trace \u2014 eau env., etc.)<\/text>\n  <text x=\"350\" y=\"140\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"10.5\" fill=\"#4ade80\">tr\u00e8s faible absorbance par mm<\/text>\n\n  <!-- Path length double arrow (below cuvette) -->\n  <line x1=\"102\" y1=\"196\" x2=\"598\" y2=\"196\" stroke=\"#166534\" stroke-width=\"1.8\"\/>\n  <polygon points=\"102,191 102,201 92,196\" fill=\"#166534\"\/>\n  <polygon points=\"598,191 598,201 608,196\" fill=\"#166534\"\/>\n  <text x=\"350\" y=\"213\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"12\" font-weight=\"700\" fill=\"#166534\">trajet de 100 mm = 10 cm dans la formule de Beer-Lambert<\/text>\n\n  <!-- Light beam entering LEFT -->\n  <defs>\n    <marker id=\"arrowG1\" markerWidth=\"8\" markerHeight=\"6\" refX=\"8\" refY=\"3\" orient=\"auto\">\n      <polygon points=\"0,0 8,3 0,6\" fill=\"#f59e0b\"\/>\n    <\/marker>\n    <marker id=\"arrowG2\" markerWidth=\"8\" markerHeight=\"6\" refX=\"8\" refY=\"3\" orient=\"auto\">\n      <polygon points=\"0,0 8,3 0,6\" fill=\"#15803d\"\/>\n    <\/marker>\n  <\/defs>\n  <!-- Entering beam (bright) \u2014 comes from left edge, stops at left wall -->\n  <line x1=\"14\" y1=\"118\" x2=\"78\" y2=\"118\" stroke=\"#f59e0b\" stroke-width=\"3\" marker-end=\"url(#arrowG1)\"\/>\n  <text x=\"46\" y=\"108\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"11\" fill=\"#b45309\" font-weight=\"600\">Entr\u00e9e<\/text>\n\n  <!-- Exiting beam right \u2014 slightly attenuated but still strong (dilute sample) -->\n  <line x1=\"622\" y1=\"118\" x2=\"686\" y2=\"118\" stroke=\"#15803d\" stroke-width=\"2.5\" marker-end=\"url(#arrowG2)\"\/>\n  <text x=\"654\" y=\"108\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"11\" fill=\"#166534\" font-weight=\"600\">Sortie<\/text>\n\n  <!-- Long beam traversing sample (dashed yellow inside) -->\n  <line x1=\"102\" y1=\"118\" x2=\"598\" y2=\"118\" stroke=\"#f59e0b\" stroke-width=\"2\" stroke-dasharray=\"8,5\" opacity=\"0.6\"\/>\n\n  <!-- Wall labels -->\n  <text x=\"91\" y=\"50\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"10\" fill=\"#4b5563\">Paroi<\/text>\n  <text x=\"91\" y=\"60\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"10\" fill=\"#4b5563\">en quartz<\/text>\n  <text x=\"609\" y=\"50\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"10\" fill=\"#4b5563\">Paroi<\/text>\n  <text x=\"609\" y=\"60\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"10\" fill=\"#4b5563\">en quartz<\/text>\n\n  <!-- Sensitivity callout -->\n  <rect x=\"440\" y=\"225\" width=\"248\" height=\"10\" fill=\"none\"\/>\n  <text x=\"350\" y=\"233\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"11\" fill=\"#166534\" font-weight=\"600\">10\u00d7 la sensibilit\u00e9 d\u2019une cuve standard de 10 mm<\/text>\n\n<\/svg>\n<p style=\"text-align:center;font-size:12px;color:#888;margin:8px 0 0;\">Cuve \u00e0 long trajet (100 mm montr\u00e9) : le faisceau parcourt 100 mm \u00e0 travers l\u2019\u00e9chantillon, accumulant 10\u00d7 plus d\u2019absorbance par unit\u00e9 de concentration qu\u2019une cuve standard \u2014 id\u00e9al pour l\u2019analyse de traces.<\/p>\n<\/div>\n\n<p>Les cuves \u00e0 long trajet (20\u2013200 mm) \u00e9tendent la capacit\u00e9 de d\u00e9tection aux \u00e9chantillons tr\u00e8s dilu\u00e9s en multipliant le trajet de Beer-Lambert effectif. Elles sont l\u2019outil standard de l\u2019analyse environnementale et de l\u2019eau, et de toute application o\u00f9 l\u2019\u00e9chantillon ne peut \u00eatre concentr\u00e9.<\/p>\n\n<div class=\"csg-table-wrap\">\n  <table class=\"csg-table\">\n    <thead>\n      <tr>\n        <th>Application<\/th>\n        <th>Analyte typique<\/th>\n        <th>Plage de concentration<\/th>\n        <th>Trajet recommand\u00e9<\/th>\n        <th>M\u00e9thode de r\u00e9f\u00e9rence<\/th>\n      <\/tr>\n    <\/thead>\n    <tbody>\n      <tr>\n        <td>Couleur de l\u2019eau potable<\/td>\n        <td>Couleur organique dissoute<\/td>\n        <td>1\u201350 PCU<\/td>\n        <td>100 mm<\/td>\n        <td><a href=\"https:\/\/www.standardmethods.org\/\" target=\"_blank\" rel=\"noopener\">APHA 2120 C<\/a><\/td>\n      <\/tr>\n      <tr>\n        <td>Nitrate des eaux us\u00e9es<\/td>\n        <td>NO\u2083\u207b \u00e0 220 nm<\/td>\n        <td>0,1\u20135 mg\/L<\/td>\n        <td>50\u2013100 mm<\/td>\n        <td><a href=\"https:\/\/www.epa.gov\/sites\/default\/files\/2015-08\/documents\/method_300-0_rev_2-1_1993.pdf\" target=\"_blank\" rel=\"noopener\">EPA 300.0<\/a><\/td>\n      <\/tr>\n      <tr>\n        <td>Chrome (VI) trace<\/td>\n        <td>CrO\u2084\u00b2\u207b<\/td>\n        <td>0,01\u20130,5 mg\/L<\/td>\n        <td>100 mm<\/td>\n        <td>APHA 3500-Cr<\/td>\n      <\/tr>\n      <tr>\n        <td>Oxyg\u00e8ne dissous (indirect)<\/td>\n        <td>R\u00e9actif de Winkler<\/td>\n        <td>Couleur dilu\u00e9e<\/td>\n        <td>50\u2013100 mm<\/td>\n        <td>APHA 4500-O<\/td>\n      <\/tr>\n      <tr>\n        <td>Absorbance en phase gazeuse<\/td>\n        <td>SO\u2082, NO\u2082 en cuves \u00e0 gaz<\/td>\n        <td>niveau ppm<\/td>\n        <td>100\u2013200 mm<\/td>\n        <td>EPA TO-11A<\/td>\n      <\/tr>\n      <tr>\n        <td>CQ de colorant \/ pigment dilu\u00e9<\/td>\n        <td>Colorants alimentaires, colorants textiles<\/td>\n        <td>0,001\u20130,1 mg\/L<\/td>\n        <td>50\u2013100 mm<\/td>\n        <td>M\u00e9thodes internes<\/td>\n      <\/tr>\n      <tr>\n        <td>M\u00e9taux ultra-traces (colorim\u00e9trie)<\/td>\n        <td>Fe, Mn par ch\u00e9lation<\/td>\n        <td><0.1 mg\/L<\/td>\n        <td>100\u2013200 mm<\/td>\n        <td>s\u00e9rie APHA 3500<\/td>\n      <\/tr>\n    <\/tbody>\n  <\/table>\n<\/div>\n\n<h3>Cuve 100 mm : standard pour l\u2019analyse environnementale et de traces<\/h3>\n\n<p>La <strong>cuve de 100 mm<\/strong> (trajet optique 100 mm, Beer-Lambert l = 10 cm) offre exactement 10\u00d7 la sensibilit\u00e9 d\u2019une cuve standard de 10 mm. C\u2019est la cuve \u00e0 long trajet la plus sp\u00e9cifi\u00e9e et elle est r\u00e9f\u00e9renc\u00e9e nomm\u00e9ment dans les m\u00e9thodes d\u2019analyse d\u2019eau APHA, EPA et ISO. Une cuve de 100 mm permet de d\u00e9tecter des analytes \u00e0 des concentrations 10\u00d7 plus basses que ce qui produirait un signal mesurable dans une cuve standard. <em>l<\/em> Usages courants d\u2019une cuve de 100 mm : mesure de couleur de l\u2019eau potable (APHA 2120C exige un trajet de 100 mm), chrome VI trace dans les eaux us\u00e9es (APHA 3500-Cr), nitrate \u00e0 220 nm en surveillance environnementale, mesures indirectes de carbone organique dissous, et toute analyse colorim\u00e9trique \u00e0 des concentrations au niveau du ppb. Nous fabriquons nos cuves de 100 mm en quartz JGS1 \u2014 le m\u00eame mat\u00e9riau de qualit\u00e9 optique utilis\u00e9 dans les instruments \u00e0 UV sous vide \u2014 pour maintenir une transparence totale jusqu\u2019\u00e0 185 nm, ce qui est critique pour la d\u00e9tection de nitrate et nitrite \u00e0 220 nm. En pratique, le trajet de 100 mm est la taille non standard la plus demand\u00e9e que nous produisons, presque enti\u00e8rement motiv\u00e9e par les exigences de conformit\u00e9 aux m\u00e9thodes APHA et EPA des labos environnementaux.<\/p>\n\n<p>Consid\u00e9ration de volume :<\/p>\n\n<div class=\"csg-highlight\">\n  <strong>Une cuve macro de 100 mm contient 35 mL d\u2019\u00e9chantillon. Si le volume d\u2019\u00e9chantillon est limit\u00e9, une microcuve \u00e0 long trajet peut ne pas \u00eatre pratique. Pour l\u2019analyse d\u2019eau o\u00f9 de grands volumes sont disponibles, 100 mm est standard. Pour les \u00e9chantillons environnementaux de terrain \u00e0 volume limit\u00e9, envisagez des configurations de cuve \u00e0 circulation.<\/strong> Section 7\n<\/div>\n<\/div>\n\n<div id=\"z-height\">\n<p class=\"csg-label\">Trajet optique vs hauteur Z : comprendre les deux dimensions<\/p>\n<h2>Le trajet optique et la hauteur Z sont deux dimensions de cuve diff\u00e9rentes, fr\u00e9quemment confondues. Les deux comptent, mais pour des raisons compl\u00e8tement diff\u00e9rentes.<\/h2>\n\n<p>La distance horizontale que le faisceau parcourt \u00e0 travers l\u2019\u00e9chantillon \u2014 la distance entre les deux fen\u00eatres optiques. D\u00e9termine la sensibilit\u00e9 d\u2019absorbance. Vous la choisissez selon votre concentration d\u2019\u00e9chantillon et le calcul de Beer-Lambert. Affecte directement votre r\u00e9sultat de mesure.<\/p>\n\n<div class=\"csg-card-grid-2\">\n  <div class=\"csg-card\">\n    <div class=\"csg-card-icon\">\u2194\ufe0f<\/div>\n    <h3>Trajet optique<\/h3>\n    <p>Hauteur Z<\/p>\n  <\/div>\n  <div class=\"csg-card\">\n    <div class=\"csg-card-icon\">\u2195\ufe0f<\/div>\n    <h3>La distance verticale du fond de la cuve au centre du faisceau dans votre instrument. Fix\u00e9e par votre mod\u00e8le de spectrophotom\u00e8tre \u2014 pas un choix de l\u2019utilisateur. D\u00e9termine si le faisceau passe r\u00e9ellement \u00e0 travers l\u2019\u00e9chantillon (et non l\u2019air au-dessus). Mauvaise hauteur Z = pas de signal ou lectures incorrectes.<\/h3>\n    <p>TRAJET OPTIQUE vs HAUTEUR Z \u2014 deux dimensions diff\u00e9rentes<\/p>\n  <\/div>\n<\/div>\n\n<!-- SVG 4: Path length vs Z-height diagram -->\n<div style=\"background:#f7f8fc;border-radius:12px;padding:20px 16px 14px;margin:0 0 24px;\">\n<svg viewBox=\"0 0 700 260\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" style=\"width:100%;max-width:700px;display:block;margin:0 auto;\" aria-label=\"Sch\u00e9ma comparant le trajet optique (horizontal) et la hauteur Z (vertical) d'une cuve\">\n  <rect width=\"700\" height=\"260\" fill=\"#f7f8fc\" rx=\"8\"\/>\n  <text x=\"350\" y=\"18\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"12.5\" font-weight=\"700\" fill=\"#1a1a2e\" letter-spacing=\"1\">Cuve macro standard (10 mm)<\/text>\n\n  <!-- ===== LEFT: Standard macro cuvette ===== -->\n  <text x=\"175\" y=\"40\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"11\" font-weight=\"700\" fill=\"#233a95\">l\u2019\u00e9chantillon remplit<\/text>\n\n  <!-- Cuvette front view -->\n  <rect x=\"100\" y=\"52\" width=\"150\" height=\"160\" rx=\"4\" fill=\"rgba(147,197,253,0.15)\" stroke=\"#233a95\" stroke-width=\"2\"\/>\n  <!-- Left wall -->\n  <rect x=\"100\" y=\"52\" width=\"22\" height=\"160\" fill=\"rgba(147,197,253,0.4)\" stroke=\"#233a95\" stroke-width=\"1.2\"\/>\n  <!-- Right wall -->\n  <rect x=\"228\" y=\"52\" width=\"22\" height=\"160\" fill=\"rgba(147,197,253,0.4)\" stroke=\"#233a95\" stroke-width=\"1.2\"\/>\n  <!-- Sample fill (macro = fills high, no Z issue) -->\n  <rect x=\"122\" y=\"72\" width=\"106\" height=\"140\" fill=\"rgba(59,130,246,0.18)\" rx=\"2\"\/>\n  <text x=\"175\" y=\"140\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"10\" fill=\"#1e40af\">jusqu\u2019en haut<\/text>\n  <text x=\"175\" y=\"153\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"10\" fill=\"#1e40af\">faisceau<\/text>\n\n  <!-- Instrument light beam (horizontal line through middle) -->\n  <line x1=\"60\" y1=\"150\" x2=\"98\" y2=\"150\" stroke=\"#f59e0b\" stroke-width=\"2.5\"\/>\n  <line x1=\"252\" y1=\"150\" x2=\"290\" y2=\"150\" stroke=\"#ef4444\" stroke-width=\"2\"\/>\n  <line x1=\"122\" y1=\"150\" x2=\"228\" y2=\"150\" stroke=\"#f59e0b\" stroke-width=\"2\" stroke-dasharray=\"5,3\" opacity=\"0.7\"\/>\n  <text x=\"45\" y=\"147\" font-family=\"Arial,sans-serif\" font-size=\"10\" fill=\"#b45309\" text-anchor=\"end\">Trajet optique = 10 mm \u2194<\/text>\n\n  <!-- PATH LENGTH arrow (horizontal) -->\n  <line x1=\"122\" y1=\"228\" x2=\"228\" y2=\"228\" stroke=\"#233a95\" stroke-width=\"1.8\"\/>\n  <polygon points=\"122,224 122,232 113,228\" fill=\"#233a95\"\/>\n  <polygon points=\"228,224 228,232 237,228\" fill=\"#233a95\"\/>\n  <text x=\"175\" y=\"244\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"10.5\" font-weight=\"700\" fill=\"#233a95\">pas un<\/text>\n\n  <!-- Z-height arrow (vertical) \u2014 from bottom to beam center -->\n  <line x1=\"80\" y1=\"212\" x2=\"80\" y2=\"152\" stroke=\"#22c55e\" stroke-width=\"1.8\"\/>\n  <polygon points=\"76,152 84,152 80,143\" fill=\"#22c55e\"\/>\n  <polygon points=\"76,212 84,212 80,221\" fill=\"#22c55e\"\/>\n  <text x=\"38\" y=\"188\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"9.5\" fill=\"#166534\" font-weight=\"700\">La distance verticale du fond de la cuve au centre du faisceau dans votre instrument. Fix\u00e9e par votre mod\u00e8le de spectrophotom\u00e8tre \u2014 pas un choix de l\u2019utilisateur. D\u00e9termine si le faisceau passe r\u00e9ellement \u00e0 travers l\u2019\u00e9chantillon (et non l\u2019air au-dessus). Mauvaise hauteur Z = pas de signal ou lectures incorrectes.<\/text>\n  <text x=\"38\" y=\"200\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"9\" fill=\"#166534\">probl\u00e8me \u2713<\/text>\n  <text x=\"38\" y=\"210\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"9\" fill=\"#166534\">Sub-microcuve (doit correspondre \u00e0 Z)<\/text>\n\n  <!-- Bottom of cuvette marker -->\n  <line x1=\"100\" y1=\"212\" x2=\"250\" y2=\"212\" stroke=\"#64748b\" stroke-width=\"1\" stroke-dasharray=\"3,3\"\/>\n\n  <!-- ===== RIGHT: Sub-micro cuvette ===== -->\n  <text x=\"525\" y=\"40\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"11\" font-weight=\"700\" fill=\"#dc2626\">petit<\/text>\n\n  <!-- Cuvette front view -->\n  <rect x=\"450\" y=\"52\" width=\"150\" height=\"160\" rx=\"4\" fill=\"rgba(252,165,165,0.1)\" stroke=\"#dc2626\" stroke-width=\"2\"\/>\n  <!-- Left wall -->\n  <rect x=\"450\" y=\"52\" width=\"22\" height=\"160\" fill=\"rgba(252,165,165,0.35)\" stroke=\"#dc2626\" stroke-width=\"1.2\"\/>\n  <!-- Right wall -->\n  <rect x=\"578\" y=\"52\" width=\"22\" height=\"160\" fill=\"rgba(252,165,165,0.35)\" stroke=\"#dc2626\" stroke-width=\"1.2\"\/>\n  <!-- Small sample volume (only partially fills) -->\n  <rect x=\"472\" y=\"162\" width=\"106\" height=\"50\" fill=\"rgba(239,68,68,0.2)\" rx=\"2\"\/>\n  <text x=\"525\" y=\"185\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"10\" fill=\"#991b1b\">vol. d\u2019\u00e9chantillon<\/text>\n  <text x=\"525\" y=\"197\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"10\" fill=\"#991b1b\">air<\/text>\n\n  <!-- Air above sample -->\n  <rect x=\"472\" y=\"72\" width=\"106\" height=\"90\" fill=\"rgba(203,213,225,0.15)\" rx=\"2\"\/>\n  <text x=\"525\" y=\"112\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"10\" fill=\"#94a3b8\">le faisceau frappe l\u2019AIR \u2717<\/text>\n\n  <!-- Instrument beam \u2014 hitting air (wrong Z) -->\n  <line x1=\"410\" y1=\"120\" x2=\"448\" y2=\"120\" stroke=\"#f59e0b\" stroke-width=\"2.5\"\/>\n  <line x1=\"600\" y1=\"120\" x2=\"640\" y2=\"120\" stroke=\"#94a3b8\" stroke-width=\"1.5\" stroke-dasharray=\"3,3\"\/>\n  <text x=\"525\" y=\"117\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"9.5\" fill=\"#dc2626\" font-weight=\"700\">Z correct \u2192 le faisceau<\/text>\n  <text x=\"395\" y=\"117\" font-family=\"Arial,sans-serif\" font-size=\"10\" fill=\"#b45309\" text-anchor=\"end\">Trajet optique = 10 mm \u2194<\/text>\n\n  <!-- Correct beam position (lower, through sample) -->\n  <line x1=\"410\" y1=\"185\" x2=\"448\" y2=\"185\" stroke=\"#22c55e\" stroke-width=\"2\" stroke-dasharray=\"4,3\"\/>\n  <text x=\"525\" y=\"152\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"9\" fill=\"#166534\">frappe l\u2019\u00e9chantillon \u2713<\/text>\n  <text x=\"525\" y=\"163\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"9\" fill=\"#166534\">doit<\/text>\n\n  <!-- Z-height arrow (wrong Z shown) -->\n  <line x1=\"430\" y1=\"212\" x2=\"430\" y2=\"122\" stroke=\"#dc2626\" stroke-width=\"1.8\"\/>\n  <polygon points=\"426,122 434,122 430,113\" fill=\"#dc2626\"\/>\n  <polygon points=\"426,212 434,212 430,221\" fill=\"#dc2626\"\/>\n  <text x=\"415\" y=\"175\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"9\" fill=\"#dc2626\" font-weight=\"700\">Z<\/text>\n  <text x=\"415\" y=\"186\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"9\" fill=\"#dc2626\">correspondre !<\/text>\n  <text x=\"415\" y=\"197\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"9\" fill=\"#dc2626\">Trajet optique (horizontal \u2014 l de Beer-Lambert)<\/text>\n\n  <!-- PATH LENGTH arrow (horizontal) -->\n  <line x1=\"472\" y1=\"228\" x2=\"578\" y2=\"228\" stroke=\"#dc2626\" stroke-width=\"1.8\"\/>\n  <polygon points=\"472,224 472,232 463,228\" fill=\"#dc2626\"\/>\n  <polygon points=\"578,224 578,232 587,228\" fill=\"#dc2626\"\/>\n  <text x=\"525\" y=\"244\" text-anchor=\"middle\" font-family=\"Arial,sans-serif\" font-size=\"10.5\" font-weight=\"700\" fill=\"#dc2626\">pas un<\/text>\n\n  <!-- Bottom dashed line -->\n  <line x1=\"450\" y1=\"212\" x2=\"600\" y2=\"212\" stroke=\"#64748b\" stroke-width=\"1\" stroke-dasharray=\"3,3\"\/>\n\n  <!-- Divider -->\n  <line x1=\"350\" y1=\"35\" x2=\"350\" y2=\"255\" stroke=\"#e2e8f0\" stroke-width=\"1.5\" stroke-dasharray=\"4,4\"\/>\n\n  <!-- Legend -->\n  <rect x=\"190\" y=\"250\" width=\"14\" height=\"8\" rx=\"2\" fill=\"#233a95\"\/>\n  <text x=\"208\" y=\"258\" font-family=\"Arial,sans-serif\" font-size=\"10\" fill=\"#1a1a2e\">Hauteur Z (vertical \u2014 position du faisceau de l\u2019instrument)<\/text>\n  <rect x=\"430\" y=\"250\" width=\"14\" height=\"8\" rx=\"2\" fill=\"#22c55e\"\/>\n  <text x=\"448\" y=\"258\" font-family=\"Arial,sans-serif\" font-size=\"10\" fill=\"#1a1a2e\">\u00c0 gauche : la cuve macro remplit au-del\u00e0 du faisceau \u2014 la hauteur Z est sans importance. \u00c0 droite : la sub-microcuve a un petit volume \u2014 si la hauteur Z ne correspond pas \u00e0 votre instrument, le faisceau manque enti\u00e8rement l\u2019\u00e9chantillon.<\/text>\n\n<\/svg>\n<p style=\"text-align:center;font-size:12px;color:#888;margin:6px 0 0;\">La hauteur Z ne compte que pour les<\/p>\n<\/div>\n\n<p>microcuves et sub-microcuves <strong>o\u00f9 le volume d\u2019\u00e9chantillon est petit et le niveau de liquide peut ne pas atteindre la hauteur de faisceau de l\u2019instrument. Les cuves macro standard (3,5 mL en trajet 10 mm) remplissent bien au-dessus de tout faisceau d\u2019instrument et la hauteur Z n\u2019est pas une pr\u00e9occupation.<\/strong> Type de cuve<\/p>\n\n<div class=\"csg-table-wrap\">\n  <table class=\"csg-table\">\n    <thead>\n      <tr>\n        <th>Instruments qui l\u2019utilisent<\/th>\n        <th>La distance verticale du fond de la cuve au centre du faisceau dans votre instrument. Fix\u00e9e par votre mod\u00e8le de spectrophotom\u00e8tre \u2014 pas un choix de l\u2019utilisateur. D\u00e9termine si le faisceau passe r\u00e9ellement \u00e0 travers l\u2019\u00e9chantillon (et non l\u2019air au-dessus). Mauvaise hauteur Z = pas de signal ou lectures incorrectes.<\/th>\n        <th>Macro standard (3,5 mL)<\/th>\n      <\/tr>\n    <\/thead>\n    <tbody>\n      <tr>\n        <td>Sans objet \u2014 remplit au-del\u00e0 de toutes les hauteurs de faisceau<\/td>\n        <td>Tous les spectrophotom\u00e8tres standard<\/td>\n        <td>Semi-micro (400 \u00b5L)<\/td>\n      <\/tr>\n      <tr>\n        <td>15\u201320 mm (typique)<\/td>\n        <td>Shimadzu UV-1900, s\u00e9rie Thermo GENESYS<\/td>\n        <td>Sub-micro, Z=8,5 mm<\/td>\n      <\/tr>\n      <tr>\n        <td>8,5 mm<\/td>\n        <td>Beckman s\u00e9rie DU, Eppendorf BioPhotometer<\/td>\n        <td>Sub-micro, Z=12 mm<\/td>\n      <\/tr>\n      <tr>\n        <td>12 mm<\/td>\n        <td>Jasco V-530\/550\/560\/570<\/td>\n        <td>Sub-micro, Z=15 mm<\/td>\n      <\/tr>\n      <tr>\n        <td>15 mm<\/td>\n        <td>PerkinElmer Lambda, Shimadzu UV-1900, Thermo Evolution<\/td>\n        <td>Sub-micro, Z=20 mm<\/td>\n      <\/tr>\n      <tr>\n        <td>Agilent Cary 60, certains mod\u00e8les PerkinElmer<\/td>\n        <td>20 mm<\/td>\n        <td>Outil de recherche de dimension Z<\/td>\n      <\/tr>\n    <\/tbody>\n  <\/table>\n<\/div>\n\n<div class=\"csg-tool-box\">\n  <div class=\"csg-tool-icon\">\ud83d\udccf<\/div>\n  <div class=\"csg-tool-text\">\n    <h4>Pas s\u00fbr de la hauteur Z qu\u2019exige votre instrument ? L\u2019outil de recherche de dimension Z de MachinedQuartz vous permet de chercher par marque et mod\u00e8le d\u2019instrument pour trouver la bonne hauteur Z pour toute commande de sub-microcuve ou microcuve.<\/h4>\n    <p>Recherchez la hauteur Z de votre instrument \u2192<\/p>\n    <a href=\"https:\/\/machinedquartz.com\/fr\/dimension-z-cuves-spectrophotometre\/\">Section 8<\/a>\n  <\/div>\n<\/div>\n<\/div>\n\n<div id=\"accuracy\">\n<p class=\"csg-label\">Exactitude et tol\u00e9rance du trajet optique<\/p>\n<h2>L\u2019exactitude du trajet optique compte le plus dans les applications quantitatives o\u00f9 le trajet optique r\u00e9el de la cuve affecte directement les concentrations calcul\u00e9es. Une cuve \u00e0 trajet optique nominal de 10 mm mais r\u00e9ellement de 9,8 mm fera que tous les calculs de Beer-Lambert seront erron\u00e9s de 2 % \u2014 acceptable pour le criblage, probl\u00e9matique pour les dosages r\u00e9glement\u00e9s.<\/h2>\n\n<p>Classe de tol\u00e9rance<\/p>\n\n<div class=\"csg-table-wrap\">\n  <table class=\"csg-table\">\n    <thead>\n      <tr>\n        <th>Erreur de trajet optique<\/th>\n        <th>Erreur d\u2019absorbance \u00e0 A=1,0<\/th>\n        <th>Adapt\u00e9e \u00e0<\/th>\n        <th>Standard (\u00b10,05 mm)<\/th>\n      <\/tr>\n    <\/thead>\n    <tbody>\n      <tr>\n        <td>\u00b10,5 % \u00e0 10 mm<\/td>\n        <td>Criblage courant, dosages g\u00e9n\u00e9raux<\/td>\n        <td>\u00b10.005 A<\/td>\n        <td>Pr\u00e9cision (\u00b10,02 mm)<\/td>\n      <\/tr>\n      <tr>\n        <td>\u00b10,2 % \u00e0 10 mm<\/td>\n        <td>Analyse quantitative, d\u00e9veloppement de m\u00e9thode<\/td>\n        <td>\u00b10.002 A<\/td>\n        <td>Ultra-pr\u00e9cision (\u00b10,01 mm)<\/td>\n      <\/tr>\n      <tr>\n        <td>\u00b10,1 % \u00e0 10 mm<\/td>\n        <td>Pharmacop\u00e9e, \u00e9talons de r\u00e9f\u00e9rence, \u00e9talonnage<\/td>\n        <td>\u00b10.001 A<\/td>\n        <td>Pour les cuves \u00e0 court trajet, la tol\u00e9rance devient proportionnellement plus importante. Une erreur de \u00b10,05 mm sur une cuve de 1 mm est de \u00b15 % \u2014 dix fois l\u2019erreur relative de la m\u00eame tol\u00e9rance absolue sur une cuve de 10 mm. Pour les trajets sous 2 mm, sp\u00e9cifiez une tol\u00e9rance plus serr\u00e9e (\u00b10,02 mm ou \u00b10,01 mm) pour le travail quantitatif.<\/td>\n      <\/tr>\n    <\/tbody>\n  <\/table>\n<\/div>\n\n<p>Dans notre proc\u00e9d\u00e9 de fabrication, le trajet optique est v\u00e9rifi\u00e9 optiquement par interf\u00e9rom\u00e9trie de pr\u00e9cision sur chaque cuve avant exp\u00e9dition \u2014 pas estim\u00e9 d\u2019apr\u00e8s les dimensions d\u2019outillage. Nos cuves de qualit\u00e9 pr\u00e9cision de 10 mm mesurent constamment 9,998\u201310,002 mm, et nous rejetons toute cuve hors de \u00b10,02 mm pour cette qualit\u00e9. Cela nous donne confiance dans les donn\u00e9es de tol\u00e9rance du tableau ci-dessus, qui refl\u00e8tent des statistiques de production r\u00e9elles plut\u00f4t que des sp\u00e9cifications nominales.<\/p>\n\n<p>Des certificats de trajet optique tra\u00e7ables \u00e0 l\u2019<\/p>\n\n<p>ASTM E275 <a href=\"https:\/\/www.astm.org\/e0275-08r17.html\" target=\"_blank\" rel=\"noopener\">sont disponibles chez MachinedQuartz sur demande. Ils fournissent le trajet optique mesur\u00e9 (non nominal) et des donn\u00e9es de transmission aux longueurs d\u2019onde de r\u00e9f\u00e9rence, adapt\u00e9s \u00e0 un usage de laboratoire accr\u00e9dit\u00e9<\/a> ISO\/IEC 17025 <a href=\"https:\/\/www.iso.org\/standard\/66912.html\" target=\"_blank\" rel=\"noopener\">.<\/a>Section 9<\/p>\n<\/div>\n\n<div id=\"calculator\">\n<p class=\"csg-label\">Calculateur de trajet optique<\/p>\n<h2 id=\"path-length-calculator\">Utilisez les calculateurs interactifs ci-dessous pour r\u00e9soudre directement les probl\u00e8mes de Beer-Lambert :<\/h2>\n\n<p>Calculateur de trajet optique (interactif)<\/p>\n\n<div class=\"csg-tool-box\">\n  <div class=\"csg-tool-icon\">\ud83e\uddee<\/div>\n  <div class=\"csg-tool-text\">\n    <h4>Calculez le trajet optique recommand\u00e9 \u00e0 partir de l\u2019absorptivit\u00e9 molaire et de la concentration de votre \u00e9chantillon, ou r\u00e9solvez la concentration \u00e0 partir d\u2019une absorbance mesur\u00e9e. Prend en charge des valeurs de \u03b5 personnalis\u00e9es ou la recherche par analyte courant.<\/h4>\n    <p>Ouvrir le calculateur interactif \u2192<\/p>\n    <a href=\"https:\/\/machinedquartz.com\/path-length-calculator\/\">Pour r\u00e9f\u00e9rence rapide, le tableau ci-dessous donne des recommandations de trajet optique pour les applications UV-Vis les plus courantes :<\/a>\n  <\/div>\n<\/div>\n\n<p>Longueur d\u2019onde<\/p>\n\n<div class=\"csg-table-wrap\">\n  <table class=\"csg-table\">\n    <thead>\n      <tr>\n        <th>Application<\/th>\n        <th>\u03b5 typique (L mol\u207b\u00b9 cm\u207b\u00b9)<\/th>\n        <th>Concentration typique<\/th>\n        <th>Prot\u00e9ine (A\u2082\u2088\u2080, BSA)<\/th>\n        <th>Trajet recommand\u00e9<\/th>\n      <\/tr>\n    <\/thead>\n    <tbody>\n      <tr>\n        <td>280 nm<\/td>\n        <td>0,1\u20131 mg\/mL<\/td>\n        <td>43,824<\/td>\n        <td>au-dessus de 5 mg\/mL<\/td>\n        <td>10 mm<\/td>\n      <\/tr>\n      <tr>\n        <td>Protein, concentrated (>5\u201350 mg\/mL<\/td>\n        <td>0,1\u20131 mg\/mL<\/td>\n        <td>43,824<\/td>\n        <td>1\u20132 mm<\/td>\n        <td>ADN \/ ARN (A\u2082\u2086\u2080)<\/td>\n      <\/tr>\n      <tr>\n        <td>260 nm<\/td>\n        <td>0,01\u20131 mg\/mL<\/td>\n        <td>~10,000\u201350,000*<\/td>\n        <td>Dosage enzymatique NADH<\/td>\n        <td>10 mm<\/td>\n      <\/tr>\n      <tr>\n        <td>340 nm<\/td>\n        <td>0,05\u20130,5 mM<\/td>\n        <td>6,220<\/td>\n        <td>H\u00e9moglobine<\/td>\n        <td>10 mm<\/td>\n      <\/tr>\n      <tr>\n        <td>415 nm<\/td>\n        <td>0,01\u20130,1 mg\/mL<\/td>\n        <td>125,000<\/td>\n        <td>Chlorophylle a<\/td>\n        <td>10 mm<\/td>\n      <\/tr>\n      <tr>\n        <td>665 nm<\/td>\n        <td>0,001\u20130,05 mg\/mL<\/td>\n        <td>86,340<\/td>\n        <td>Nitrate dans l\u2019eau<\/td>\n        <td>10 mm<\/td>\n      <\/tr>\n      <tr>\n        <td>220 nm<\/td>\n        <td>Couleur de l\u2019eau (Pt-Co)<\/td>\n        <td>~9,700<\/td>\n        <td>0,1\u20135 mg\/L<\/td>\n        <td>50\u2013100 mm<\/td>\n      <\/tr>\n      <tr>\n        <td>465 nm<\/td>\n        <td>Faible<\/td>\n        <td>1\u2013100 PCU<\/td>\n        <td>*\u03b5 de l\u2019ADN\/ARN varie selon la composition et la longueur de la s\u00e9quence. Utilisez des coefficients d\u2019extinction sp\u00e9cifiques \u00e0 la s\u00e9quence pour une quantification pr\u00e9cise.<\/td>\n        <td>100 mm<\/td>\n      <\/tr>\n    <\/tbody>\n  <\/table>\n<\/div>\n<p style=\"font-size:12px;color:#888;\">Besoin d\u2019un trajet optique pr\u00e9cis ?<\/p>\n<\/div>\n\n<div class=\"csg-cta\">\n  <h3>MachinedQuartz fabrique des cuves en quartz JGS1 en trajets optiques de 0,1 mm \u00e0 200 mm. Le stock standard couvre les tailles les plus courantes ; trajets optiques sur mesure disponibles avec un d\u00e9lai de 5 \u00e0 8 jours.<\/h3>\n  <p>Fait confiance par les labos de recherche universitaires, les services de CQ pharmaceutique et les laboratoires environnementaux certifi\u00e9s EPA.<\/p>\n  <p style=\"font-size:13px;color:rgba(255,255,255,.65);margin:0 0 22px;\">Parcourir par trajet optique<\/p>\n  <a href=\"https:\/\/machinedquartz.com\/product-category\/products\/cuvettes\/quartz-standard-cuvettes\/\" class=\"csg-cta-btn\">Devis trajet optique sur mesure<\/a>\n  <a href=\"https:\/\/machinedquartz.com\/fr\/cuves-quartz-sur-mesure\/\" class=\"csg-cta-btn csg-cta-btn-outline\">Section 10<\/a>\n<\/div>\n\n<div id=\"faq\">\n<p class=\"csg-label\">Questions fr\u00e9quentes<\/p>\n<h2>Quel est le trajet optique de cuve standard ?<\/h2>\n\n<div class=\"csg-faq\">\n\n  <div class=\"csg-faq-item\">\n    <div class=\"csg-faq-q\">Le trajet optique de cuve standard est de 10 mm (1 cm). C\u2019est le choix par d\u00e9faut de presque toutes les m\u00e9thodes de spectrophotom\u00e9trie UV-Vis, des \u00e9talonnages d\u2019instrument et des valeurs d\u2019absorptivit\u00e9 molaire (\u03b5) rapport\u00e9es dans la litt\u00e9rature. Quand un protocole dit simplement \u00ab mesurez l\u2019absorbance \u00e0 280 nm \u00bb sans pr\u00e9ciser le trajet optique, il suppose une cuve de 10 mm.<\/div>\n    <div class=\"csg-faq-a\"><p>Comment convertir le trajet optique de mm en cm pour les calculs de Beer-Lambert ?<\/p><\/div>\n  <\/div>\n\n  <div class=\"csg-faq-item\">\n    <div class=\"csg-faq-q\">Divisez le trajet optique en mm par 10. Une cuve de 10 mm = 1 cm. Une cuve de 1 mm = 0,1 cm. Une cuve de 100 mm = 10 cm. Dans l\u2019\u00e9quation de Beer-Lambert A = \u03b5 \u00d7 c \u00d7 l, le trajet optique (l) doit \u00eatre en centim\u00e8tres car l\u2019absorptivit\u00e9 molaire (\u03b5) est conventionnellement exprim\u00e9e en L mol\u207b\u00b9 cm\u207b\u00b9.<\/div>\n    <div class=\"csg-faq-a\"><p>Mon absorbance est trop \u00e9lev\u00e9e (au-dessus de 2,0). Dois-je utiliser un trajet plus court ou diluer mon \u00e9chantillon ?<\/p><\/div>\n  <\/div>\n\n  <div class=\"csg-faq-item\">\n    <div class=\"csg-faq-q\">My absorbance reading is too high (>Les deux sont valables \u2014 le choix d\u00e9pend de votre situation. Si vous avez un volume d\u2019\u00e9chantillon limit\u00e9 ou ne pouvez introduire d\u2019erreur de dilution (p. ex. formulation de prot\u00e9ine tr\u00e8s concentr\u00e9e o\u00f9 la dilution change le comportement), utilisez une cuve \u00e0 court trajet (1\u20135 mm). Si le volume d\u2019\u00e9chantillon n\u2019est pas limitant et que la dilution est acceptable pour votre dosage, diluez 5\u201310\u00d7 et utilisez votre cuve de 10 mm. Les cuves \u00e0 court trajet \u00e9liminent l\u2019arithm\u00e9tique de dilution et l\u2019erreur de pipetage associ\u00e9e, ce qui est un avantage dans les dosages r\u00e9glement\u00e9s.<\/div>\n    <div class=\"csg-faq-a\"><p>Quel trajet optique utiliser pour la quantification de prot\u00e9ine \u00e0 280 nm ?<\/p><\/div>\n  <\/div>\n\n  <div class=\"csg-faq-item\">\n    <div class=\"csg-faq-q\">Pour la plupart du travail courant sur prot\u00e9ines \u00e0 0,1\u20132 mg\/mL, une cuve de 10 mm convient. Aux concentrations au-dessus de 5 mg\/mL (courantes dans les formulations d\u2019anticorps et les solutions m\u00e8res de prot\u00e9ines concentr\u00e9es), passez \u00e0 une cuve de 1 mm ou 2 mm pour garder l\u2019absorbance sous 1,0. Au-dessus de 10 mg\/mL, envisagez 0,5 mm ou 0,2 mm. Le calculateur de trajet optique MachinedQuartz peut calculer la recommandation exacte \u00e0 partir du coefficient d\u2019extinction et de la concentration de votre prot\u00e9ine.<\/div>\n    <div class=\"csg-faq-a\"><p>Pourquoi une cuve de 100 mm a-t-elle 10\u00d7 la sensibilit\u00e9 d\u2019une cuve de 10 mm ?<\/p><\/div>\n  <\/div>\n\n  <div class=\"csg-faq-item\">\n    <div class=\"csg-faq-q\">Parce que la loi de Beer-Lambert est lin\u00e9aire : A = \u03b5 \u00d7 c \u00d7 l. Augmenter l de 1 cm (10 mm) \u00e0 10 cm (100 mm) multiplie l\u2019absorbance par 10 pour la m\u00eame concentration. Vous pouvez donc d\u00e9tecter un analyte \u00e0 0,01 mg\/L dans une cuve de 100 mm au m\u00eame niveau d\u2019absorbance qu\u2019un analyte \u00e0 0,1 mg\/L dans une cuve de 10 mm \u2014 une limite de d\u00e9tection 10\u00d7 plus basse pour le m\u00eame instrument.<\/div>\n    <div class=\"csg-faq-a\"><p>Le trajet optique est-il la m\u00eame chose que la hauteur Z ?<\/p><\/div>\n  <\/div>\n\n  <div class=\"csg-faq-item\">\n    <div class=\"csg-faq-q\">Non. Le trajet optique est la distance horizontale entre les fen\u00eatres optiques \u2014 il d\u00e9termine la sensibilit\u00e9 de Beer-Lambert et se mesure dans la direction du faisceau. La hauteur Z est la distance verticale du fond de la cuve au centre du faisceau de l\u2019instrument \u2014 elle d\u00e9termine si le faisceau passe \u00e0 travers votre (petit) volume d\u2019\u00e9chantillon. Le trajet optique est un choix que vous faites selon votre concentration ; la hauteur Z est fix\u00e9e par votre mod\u00e8le d\u2019instrument. Seules les sub-microcuves et microcuves exigent un accord de hauteur Z.<\/div>\n    <div class=\"csg-faq-a\"><p>Points cl\u00e9s \u00e0 retenir<\/p><\/div>\n  <\/div>\n\n<\/div>\n<\/div>\n\n<div style=\"background:#f0f3fc;border-left:4px solid #233a95;border-radius:0 12px 12px 0;padding:28px 32px;margin:40px 0 32px;\">\n  <p style=\"font-size:11px;font-weight:700;letter-spacing:2px;text-transform:uppercase;color:#233a95;margin:0 0 14px;\">10 mm est le choix par d\u00e9faut<\/p>\n  <ul style=\"margin:0;padding-left:20px;font-size:14px;color:#333;line-height:1.8;\">\n    <li><strong>\u2014 correct pour presque tout le travail UV-Vis courant \u00e0 des concentrations standard.<\/strong> Utilisez un court trajet (sous 10 mm)<\/li>\n    <li><strong>quand votre \u00e9chantillon est concentr\u00e9 et que l\u2019absorbance d\u00e9passerait 1,5 A dans une cuve de 10 mm.<10 mm)<\/strong> Utilisez un long trajet (au-dessus de 10 mm)<\/li>\n    <li><strong>Use long path (>10 mm)<\/strong> quand les \u00e9chantillons sont au niveau des traces et n\u00e9cessitent plus de sensibilit\u00e9 \u2014 100 mm donne 10\u00d7 le signal.<\/li>\n    <li><strong>Utilisez toujours les cm dans Beer-Lambert<\/strong> \u2014 divisez les mm par 10 avant d\u2019entrer l dans l\u2019\u00e9quation (A = \u03b5 \u00b7 c \u00b7 l).<\/li>\n    <li><strong>Trajet optique \u2260 hauteur Z<\/strong> \u2014 le trajet optique est votre choix de mesure ; la hauteur Z est fix\u00e9e par votre instrument et ne compte que pour les microcuves.<\/li>\n    <li><strong>Une tol\u00e9rance plus serr\u00e9e compte davantage aux courts trajets<\/strong> \u2014 \u00b10,05 mm fait \u00b15 % d\u2019erreur \u00e0 1 mm ; sp\u00e9cifiez \u00b10,02 mm ou mieux pour le travail quantitatif \u00e0 court trajet.<\/li>\n  <\/ul>\n  <p style=\"margin:16px 0 0;font-size:13px;color:#555;font-style:italic;\">Ce guide est r\u00e9dig\u00e9 par l\u2019\u00e9quipe technique MachinedQuartz \u2014 des ing\u00e9nieurs en optique de quartz qui fabriquent des cuves UV-Vis aux normes de tol\u00e9rance ASTM E275 et fournissent des labos de recherche, des services de CQ pharmaceutique et des laboratoires environnementaux certifi\u00e9s EPA dans le monde entier.<\/p>\n<\/div>\n\n<script>\ndocument.querySelectorAll('.csg-faq-q').forEach(function(q){\n  q.addEventListener('click',function(){\n    var item=this.closest('.csg-faq-item');\n    var wasOpen=item.classList.contains('open');\n    document.querySelectorAll('.csg-faq-item').forEach(function(i){i.classList.remove('open');});\n    if(!wasOpen)item.classList.add('open');\n  });\n});\n<\/script>\n\n<script type=\"application\/ld+json\">\n{\n  \"@context\": \"https:\/\/schema.org\",\n  \"@graph\": [\n    {\n      \"@type\": \"Article\",\n      \"headline\": \"Guide du trajet optique des cuves : comment choisir le bon trajet\",\n      \"description\": \"Le trajet optique est la dimension la plus importante d'une cuve. Ce guide explique la physique de Beer-Lambert, liste chaque trajet optique standard avec son usage, et donne un cadre pratique pour choisir.\",\n      \"datePublished\": \"2025-10-20\",\n      \"dateModified\": \"2025-10-22\",\n      \"author\": {\n        \"@type\": \"Organization\",\n        \"name\": \"MachinedQuartz\",\n        \"url\": \"https:\/\/machinedquartz.com\/\"\n      },\n      \"publisher\": {\n        \"@type\": \"Organization\",\n        \"name\": \"MachinedQuartz\",\n        \"logo\": {\n          \"@type\": \"ImageObject\",\n          \"url\": \"https:\/\/machinedquartz.com\/wp-content\/uploads\/2024\/01\/MQ-logo.png\"\n        }\n      },\n      \"mainEntityOfPage\": {\n        \"@type\": \"WebPage\",\n        \"@id\": \"https:\/\/machinedquartz.com\/fr\/guide-trajet-optique-cuves\/\"\n      },\n      \"image\": \"https:\/\/machinedquartz.com\/wp-content\/uploads\/2024\/01\/MQ-logo.png\",\n      \"inLanguage\": \"fr\"\n    },\n    {\n      \"@type\": \"FAQPage\",\n      \"mainEntity\": [\n        {\n          \"@type\": \"Question\",\n          \"name\": \"Quel est le trajet optique de cuve standard ?\",\n          \"acceptedAnswer\": {\n            \"@type\": \"Answer\",\n            \"text\": \"Le trajet optique de cuve standard est de 10 mm (1 cm). C'est le choix par d\u00e9faut de presque toutes les m\u00e9thodes de spectrophotom\u00e9trie UV-Vis, des \u00e9talonnages d'instrument et des valeurs d'absorptivit\u00e9 molaire (\u03b5) rapport\u00e9es dans la litt\u00e9rature. Quand un protocole dit simplement \u00ab mesurez l'absorbance \u00e0 280 nm \u00bb sans pr\u00e9ciser le trajet optique, il suppose une cuve de 10 mm.\"\n          }\n        },\n        {\n          \"@type\": \"Question\",\n          \"name\": \"Comment convertir le trajet optique de mm en cm pour les calculs de Beer-Lambert ?\",\n          \"acceptedAnswer\": {\n            \"@type\": \"Answer\",\n            \"text\": \"Divisez le trajet optique en mm par 10. Une cuve de 10 mm = 1 cm. Une cuve de 1 mm = 0,1 cm. Une cuve de 100 mm = 10 cm. Dans l'\u00e9quation de Beer-Lambert A = \u03b5 \u00d7 c \u00d7 l, le trajet optique (l) doit \u00eatre en centim\u00e8tres car l'absorptivit\u00e9 molaire (\u03b5) est conventionnellement exprim\u00e9e en L mol\u207b\u00b9 cm\u207b\u00b9.\"\n          }\n        },\n        {\n          \"@type\": \"Question\",\n          \"name\": \"Le trajet optique est-il la m\u00eame chose que la hauteur Z ?\",\n          \"acceptedAnswer\": {\n            \"@type\": \"Answer\",\n            \"text\": \"Non. Le trajet optique est la distance horizontale entre les fen\u00eatres optiques \u2014 il d\u00e9termine la sensibilit\u00e9 de Beer-Lambert et se mesure dans la direction du faisceau. La hauteur Z est la distance verticale du fond de la cuve au centre du faisceau de l'instrument \u2014 elle d\u00e9termine si le faisceau passe \u00e0 travers votre (petit) volume d'\u00e9chantillon. Le trajet optique est un choix que vous faites selon votre concentration ; la hauteur Z est fix\u00e9e par votre mod\u00e8le d'instrument. Seules les sub-microcuves et microcuves exigent un accord de hauteur Z.\"\n          }\n        },\n        {\n          \"@type\": \"Question\",\n          \"name\": \"Quel trajet optique utiliser pour la quantification de prot\u00e9ine \u00e0 280 nm ?\",\n          \"acceptedAnswer\": {\n            \"@type\": \"Answer\",\n            \"text\": \"Pour la plupart du travail courant sur prot\u00e9ines \u00e0 0,1\u20132 mg\/mL, une cuve de 10 mm convient. Aux concentrations au-dessus de 5 mg\/mL (courantes dans les formulations d'anticorps et les solutions m\u00e8res de prot\u00e9ines concentr\u00e9es), passez \u00e0 une cuve de 1 mm ou 2 mm pour garder l'absorbance sous 1,0. Au-dessus de 10 mg\/mL, envisagez 0,5 mm ou 0,2 mm. 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L\u00e0 o\u00f9 des normes tierces s'appliquent, nous citons directement la documentation NIST sur Beer-Lambert, l'IUPAC Gold Book et le CRC Handbook.\n  <\/div>\n<\/div>\n\n\n\n\n\n<div style=\"background:#f0f4ff;border:1px solid #c7d2fe;border-radius:10px;padding:20px 24px;margin:30px 0;\">\n\n<p style=\"margin:0 0 8px;font-weight:700;color:#3730a3;font-size:11px;letter-spacing:1.5px;text-transform:uppercase;\">Pour aller plus loin<\/p>\n\n<ul style=\"margin:0;padding-left:20px;list-style:none;\">\n\n<li style=\"padding:4px 0;\"><a href=\"https:\/\/machinedquartz.com\/fr\/loi-beer-lambert-choix-cuve\/\" style=\"color:#1e40af;font-weight:600;text-decoration:none;\">\u2192 Loi de Beer-Lambert et choix de la cuve : guide pratique<\/a><\/li>\n\n<li style=\"padding:4px 0;\"><a href=\"https:\/\/machinedquartz.com\/large-window-cuvettes-wide-beam-spectrophotometers\/\" style=\"color:#1e40af;font-weight:600;text-decoration:none;\">\u2192 Cuves \u00e0 grande fen\u00eatre pour spectrophotom\u00e8tres \u00e0 faisceau large<\/a><\/li>\n\n<\/ul>\n\n<\/div>\n\n\n\n\n<!-- mq-cuvette-cta -->\n<div style=\"background:#eef1fb;border-left:4px solid #233a95;border-radius:8px;padding:20px 24px;margin:40px 0;font-size:16px;line-height:1.7;\">\n<p style=\"font-weight:700;margin:0 0 8px;color:#1a2a6c;\">Options de cuves en stock & sur mesure<\/p>\n<p style=\"margin:0;\">Parcourez toute la gamme de <a href=\"https:\/\/machinedquartz.com\/product-category\/products\/cuvettes\/\">cuves en quartz<\/a>, explorez les <a href=\"https:\/\/machinedquartz.com\/fr\/cuves-quartz-sur-mesure\/\">cuves en quartz sur mesure<\/a> pour les trajets optiques et g\u00e9om\u00e9tries non standard, ou utilisez le <a href=\"https:\/\/machinedquartz.com\/cuvettes-and-cells-size-chart\/\">tableau des tailles de cuves<\/a> pour trouver le bon ajustement. Besoin d'un devis ? <a href=\"https:\/\/machinedquartz.com\/contact\/\">Contactez notre \u00e9quipe<\/a>.<\/p>\n<\/div>\n<!-- \/mq-cuvette-cta -->\n\n","protected":false},"excerpt":{"rendered":"<p>Le trajet optique d\u2019une cuve, c\u2019est la distance que la lumi\u00e8re parcourt \u00e0 travers l\u2019\u00e9chantillon dans une cuve de spectrophotom\u00e8tre \u2014 la variable L de la loi de Beer-Lambert A = \u03b5 \u00b7 c \u00b7 L. Les cuves standard font 10 mm ; les trajets optiques disponibles vont de 0,01 mm (cuves ultra-minces sub-microlitre) \u00e0<\/p>\n<div class=\"klb-readmore entry-button\"><a class=\"button\" href=\"https:\/\/machinedquartz.com\/fr\/guide-trajet-optique-cuves\/\">Read More<\/a><\/div>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1515,1517,1],"tags":[],"class_list":["post-98852","post","type-post","status-publish","format-standard","hentry","category-quartz-fr","category-tous-les-messages","category-uncategorized"],"_links":{"self":[{"href":"https:\/\/machinedquartz.com\/fr\/wp-json\/wp\/v2\/posts\/98852","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/machinedquartz.com\/fr\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/machinedquartz.com\/fr\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/machinedquartz.com\/fr\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/machinedquartz.com\/fr\/wp-json\/wp\/v2\/comments?post=98852"}],"version-history":[{"count":2,"href":"https:\/\/machinedquartz.com\/fr\/wp-json\/wp\/v2\/posts\/98852\/revisions"}],"predecessor-version":[{"id":98888,"href":"https:\/\/machinedquartz.com\/fr\/wp-json\/wp\/v2\/posts\/98852\/revisions\/98888"}],"wp:attachment":[{"href":"https:\/\/machinedquartz.com\/fr\/wp-json\/wp\/v2\/media?parent=98852"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/machinedquartz.com\/fr\/wp-json\/wp\/v2\/categories?post=98852"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/machinedquartz.com\/fr\/wp-json\/wp\/v2\/tags?post=98852"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}