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<div class="nist-section-header__main grid-container"> <div class="grid-row"> <div class="nist-section-header__title"> <h1 class="nist-page__title">Chemistry</h1> </div> </div> </div> </div> </div> <section class="nist-page__content usa-section clearfix" > <a id="main-content" tabindex="-1"></a> <div class="grid-container margin-top-4"> <div class="grid-row grid-gap-6"> <aside class="nist-page__region nist-page__region--sidebar-first tablet-lg:grid-col-4 desktop-lg:grid-col-3"> <div> <!-- nist-index-ignore-start --> <div data-elastic-exclude="" class="nist-block" > <nav> <ul class="usa-sidenav usa-accordion "> <li class="usa-sidenav__item"> <a href="/nist-and-nobel/dan-shechtman" data-drupal-link-system-path="">NIST and the Nobel: Dan Shechtman</a> </li> <li class="usa-sidenav__item"> <a href="/chemistry/international-year-periodic-table" data-drupal-link-system-path="">International Year of the Periodic Table</a> </li> </ul> </nav> </div> <!-- nist-index-ignore-end --> <!-- 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margin-y-5"> <div class="paragraph paragraph--type--topic-research paragraph--view-mode--default"> <div class="nist-region-heading"> <h2>The Research</h2> </div> <div class="grid-row"> <div class="tablet:grid-col-8 padding-right-5 margin-y-2"> <h2 class="nist-block__title">Projects & Programs</h2> <article about="/programs-projects/chemical-foundations-cannabis-breathalyzer" class="nist-teaser" > <div class="nist-teaser__image"> <div class="entity-reference"> <a href="/programs-projects/chemical-foundations-cannabis-breathalyzer" hreflang="en"><img loading="lazy" src="/sites/default/files/styles/thumbnail/public/images/2020/07/16/Cannabis%20Buds.jpeg?itok=I3WFsLdU" width="100" height="67" alt="Cannabis Buds" typeof="foaf:Image" /> </a> </div> </div> <div class="nist-teaser__content-wrapper"> <header> <h3 class="nist-teaser__title"><a href="/programs-projects/chemical-foundations-cannabis-breathalyzer"><span>Chemical Foundations for a Cannabis Breathalyzer</span> </a></h3> <div class="nist-teaser__type"> <div class="nist-badge display-inline-block margin-y-1 nist-badge--blue boolean">Ongoing</div> </div> </header> <div class="nist-teaser__content"> <div class="text-with-summary"> NIST's initial work in cannabis science was a series of measurements of the vapor pressure of two important cannabinoids: delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD). Our current effort is funded in part by interagency agreements with the ational Institute of Justice and by the NIST </div> </div> </div> </article> <article about="/programs-projects/development-methods-measurement-vitamin-d-and-its-metabolites-foods-fortified" class="nist-teaser" > <div class="nist-teaser__image"> <div class="entity-reference"> <a href="/programs-projects/development-methods-measurement-vitamin-d-and-its-metabolites-foods-fortified" hreflang="en"><img loading="lazy" src="/sites/default/files/styles/thumbnail/public/images/2018/09/27/triangle_with_vit_d_srms.png?itok=DGWoDSRo" width="100" height="87" alt="Triangle with Vit D SRMs" typeof="foaf:Image" /> </a> </div> </div> <div class="nist-teaser__content-wrapper"> <header> <h3 class="nist-teaser__title"><a href="/programs-projects/development-methods-measurement-vitamin-d-and-its-metabolites-foods-fortified"><span>Development of Methods for Measurement of Vitamin D and its Metabolites in Foods, Fortified Foods, and Dietary Supplements</span> </a></h3> <div class="nist-teaser__type"> <div class="nist-badge display-inline-block margin-y-1 nist-badge--blue boolean">Ongoing</div> </div> </header> <div class="nist-teaser__content"> <div class="text-with-summary"> Vitamin D exists in two forms: vitamin D2 (ergocalciferol) and vitamin D3 (cholecalciferol). Vitamin D3 is produced in the body after sun exposure and is also the form used in most fortified foods. Dietary supplements may contain either vitamin D2 or D3. Measurement of vitamin D in foods and dietary </div> </div> </div> </article> <article about="/programs-projects/differential-absorption-lidar-detection-and-quantification-greenhouse-gases" class="nist-teaser" > <div class="nist-teaser__image"> <div class="entity-reference"> <a href="/programs-projects/differential-absorption-lidar-detection-and-quantification-greenhouse-gases" hreflang="en"><img loading="lazy" src="/sites/default/files/styles/thumbnail/public/images/2019/07/23/smokestack_nagy_sm_1.jpg?itok=7sWNc7UI" width="100" height="100" alt="smokestack" typeof="foaf:Image" /> </a> </div> </div> <div class="nist-teaser__content-wrapper"> <header> <h3 class="nist-teaser__title"><a href="/programs-projects/differential-absorption-lidar-detection-and-quantification-greenhouse-gases"><span>Differential absorption LIDAR for the detection and quantification of greenhouse gases</span> </a></h3> <div class="nist-teaser__type"> <div class="nist-badge display-inline-block margin-y-1 nist-badge--blue boolean">Ongoing</div> </div> </header> <div class="nist-teaser__content"> <div class="text-with-summary"> The basic processes involved in elastic backscatter LIDAR are as follows. A laser source emits a pulse of light (typically a few nanoseconds), and as the pulse propagates, the photons interact with particles in the atmosphere. Some of these interactions, such as Mie and Rayleigh scattering, result </div> </div> </div> </article> <div class="link-list"><a href="/laboratories/projects-programs/topic/248416">View All Projects/Programs</a></div> </div> <div class="tablet:grid-col-4 margin-y-2"> <h2 class="nist-block__title">Additional Resources Links</h2> <div class="nist-field nist-field--label-hidden nist-field--link-list link nist-field--link-list font-sans-sm"> <div class="nist-field__items"> <div class="nist-field__item"><a href="/publications/search?ta%5B0%5D=248416">Publications</a></div> <div class="nist-field__item"><a href="/services-resources/software?k=&d%5Bmin%5D=&d%5Bmax%5D=&a%5B0%5D=248416&tag=">Software</a></div> <div class="nist-field__item"><a href="/laboratories/tools-instruments?k=&a%5B0%5D=248416&o=All&tag=">Tools & Instruments</a></div> </div> </div> </div> </div> </div> </div> <div class="paragraph paragraph--type--topic-featured paragraph--view-mode--default nist-content-row--width-full bg-base-lightest margin-y-5"> <div class="grid-container"> <div class="nist-card nist-card--horizontal nist-card--horizontal-full nist-card--base-lightest"> <div class="nist-card__inner"> <div class="nist-card__image"> <a href="/blogs/taking-measure/shaping-future-nist-mass-spectral-library"> <div class="entity-reference"> <figure class="nist-image"> <img src="/sites/default/files/styles/800w_x_400h/public/images/2020/06/09/Mass%20Spec%20Database%20featured%20image.jpg.webp?itok=FtURj_Ra" width="800" height="400" alt="Tytus Mak sitting at his desk and while colleague Arun Moorthy and he look at a computer screen" title="Tytus Mak and Arun Moorthy" loading="lazy" typeof="foaf:Image" /> <figcaption class="nist-image__caption"> <div data-caption-editable="true" class="nist-image__caption-content"> </div> </figcaption> </figure> </div> </a> </div> <div class="nist-card__title"> <h3> Shaping the Future of the NIST Mass Spectral Library </h3> </div> <div class="nist-card__content"> <div class="text-long"><p>When one thinks of mass spectral libraries — well, let’s be honest here, the very idea of mass spectral libraries will never cross most people’s minds, even most scientists’. But that’s true for most of the seemingly esoteric things that many of us at the National Institute of Standards and Technology (NIST) have devoted our careers to. And though many of us have often struggled to explain the nature of our work to friends and loved ones (and more often than not failed to elicit excitement), the importance of NIST’s work cannot be overstated. 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The small circle says "protect the American public from the dangers of illicit drugs" and has an icon of a mountain with a flag on top. 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