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At least 19 records

Spectroscopic chemical analysis methods and apparatus

Spectroscopic chemical analysis methods and apparatus are disclosed which employ deep ultraviolet (e.g. in the 200 nm to 300 nm spectral range) electron beam pumped wide bandgap semiconductor lasers, incoherent wide bandgap semiconductor light emitting devices, and hollow cathode metal ion lasers to perform non-contact, non-invasive detection of unknown chemical analytes. These deep ultraviolet sources enable dramatic size, weight and power consumption reductions of chemical analysis instruments. Chemical analysis instruments employed in some embodiments include capillary and gel plane electrophoresis, capillary electrochromatography, high performance liquid chromatography, flow cytometry, flow cells for liquids and aerosols, and surface detection instruments. In some embodiments, Raman spectroscopic detection methods and apparatus use ultra-narrow-band angle tuning filters, acousto-optic tuning filters, and temperature tuned filters to enable ultra-miniature analyzers for chemical identification. In some embodiments Raman analysis is conducted simultaneously with native fluorescence spectroscopy to provide high levels of sensitivity and specificity in the same instrument.

Hug, William F.↗

Spectroscopic chemical analysis methods and apparatus

Spectroscopic chemical analysis methods and apparatus are disclosed which employ deep ultraviolet (e.g. in the 200 nm to 300 nm spectral range) electron beam pumped wide bandgap semiconductor lasers, incoherent wide bandgap semiconductor light emitting devices, and hollow cathode metal ion lasers to perform non-contact, non-invasive detection of unknown chemical analytes. These deep ultraviolet sources enable dramatic size, weight and power consumption reductions of chemical analysis instruments. Chemical analysis instruments employed in some embodiments include capillary and gel plane electrophoresis, capillary electrochromatography, high performance liquid chromatography, flow cytometry, flow cells for liquids and aerosols, and surface detection instruments. In some embodiments, Raman spectroscopic detection methods and apparatus use ultra-narrow-band angle tuning filters, acousto-optic tuning filters, and temperature tuned filters to enable ultra-miniature analyzers for chemical identification. In some embodiments Raman analysis is conducted simultaneously with native fluorescence spectroscopy to provide high levels of sensitivity and specificity in the same instrument.

Hug, William F.↗

Spectroscopic chemical analysis methods and apparatus

Spectroscopic chemical analysis methods and apparatus are disclosed which employ deep ultraviolet (e.g. in the 200 nm to 300 nm spectral range) electron beam pumped wide bandgap semiconductor lasers, incoherent wide bandgap semiconductor light emitting devices, and hollow cathode metal ion lasers to perform non-contact, non-invasive detection of unknown chemical analytes. These deep ultraviolet sources enable dramatic size, weight and power consumption reductions of chemical analysis instruments. Chemical analysis instruments employed in some embodiments include capillary and gel plane electrophoresis, capillary electrochromatography, high performance liquid chromatography, flow cytometry, flow cells for liquids and aerosols, and surface detection instruments. In some embodiments, Raman spectroscopic detection methods and apparatus use ultra-narrow-band angle tuning filters, acousto-optic tuning filters, and temperature tuned filters to enable ultra-miniature analyzers for chemical identification. In some embodiments Raman analysis is conducted along with photoluminescence spectroscopy (i.e. fluorescence and/or phosphorescence spectroscopy) to provide high levels of sensitivity and specificity in the same instrument.

Hug, William F.↗

SALI chemical analysis of provided samples

SRI has completed the chemical analysis of all the samples supplied by NASA. The final batch of four samples consisted of: one inch diameter MgF2 mirror, control 1200-ID-FL3; one inch diameter neat resin, PMR-15, AO171-IV-55, half exposed and half unexposed; one inch diameter chromic acid anodized, EOIM-3 120-47 aluminum disc; and AO-exposed and unexposed samples of fullerene extract material in powdered form, pressed into In foil for analysis. Chemical analyses of the surfaces were performed by the surface analysis by laser ionization (SALI) method. The analyses emphasize surface contamination or general organic composition. SALI uses nonselective photoionization of sputtered or desorbed atoms and molecules above but close (approximately one mm) to the surface, followed by time-of-flight (TOF) mass spectrometry. In these studies, we used laser-induced desorption by 5-ns pulse-width 355-nm light (10-100 mJ/sq cm) and single-photon ionization (SPI) by coherent 118-nm radiation (at approximately 5 x 10(exp 5) W/sq cm). SPI was chosen primarily for its ability to obtain molecular information, whereas multiphoton ionization (not used in the present studies) is intended primarily for elemental and small molecule information. In addition to these four samples, the Au mirror (EOIM-3 200-11, sample four) was depth profiled again. Argon ion sputtering was used together with photoionization with intense 355-nm radiation (35-ps pulsewidths). Depth profiles are similar to those reported earlier, showing reproducibility. No chromium was found in the sample above noise level; its presence could at most be at the trace level. Somewhat more Ni appears to be present in the Au layer in the unexposed side, indicating thermal diffusion without chemical enhancement. The result of the presence of oxygen is apparently to tie-up/draw out the Ni as an oxide at the surface. The exposed region has a brownish tint appearance to the naked eye.

Becker, Christopher H.↗

Spectroscopic Chemical Analysis Methods and Apparatus

Spectroscopic chemical analysis methods and apparatus are disclosed which employ deep ultraviolet (e.g. in the 200 nm to 300 nm spectral range) electron beam pumped wide bandgap semiconductor lasers, incoherent wide bandgap semiconductor light emitting devices, and hollow cathode metal ion lasers to perform non-contact, non-invasive detection of unknown chemical analytes. These deep ultraviolet sources enable dramatic size, weight and power consumption reductions of chemical analysis instruments. In some embodiments, Raman spectroscopic detection methods and apparatus use ultra-narrow-band angle tuning filters, acousto-optic tuning filters, and temperature tuned filters to enable ultra-miniature analyzers for chemical identification. In some embodiments Raman analysis is conducted along with photoluminescence spectroscopy (i.e. fluorescence and/or phosphorescence spectroscopy) to provide high levels of sensitivity and specificity in the same instrument.

Hug, William F.↗

Spectroscopic Chemical Analysis Methods and Apparatus

Spectroscopic chemical analysis methods and apparatus are disclosed which employ deep ultraviolet (e.g. in the 200 nm to 300 nm spectral range) electron beam pumped wide bandgap semiconductor lasers, incoherent wide bandgap semiconductor light emitting devices, and hollow cathode metal ion lasers to perform non-contact, non-invasive detection of unknown chemical analytes. These deep ultraviolet sources enable dramatic size, weight and power consumption reductions of chemical analysis instruments. In some embodiments, Raman spectroscopic detection methods and apparatus use ultra-narrow-band angle tuning filters, acousto-optic tuning filters, and temperature tuned filters to enable ultra-miniature analyzers for chemical identification. In some embodiments Raman analysis is conducted along with photoluminescence spectroscopy (i.e. fluorescence and/or phosphorescence spectroscopy) to provide high levels of sensitivity and specificity in the same instrument.

Hug, William F.↗

Analytical/Operational Requirements for the In Situ Chemical Analysis of Cometary and Planetary Environments Using GC-IMS

Exobiology flight experiments require highly sensitive instrumentation for the in situ analysis of the volatile chemical species that occur in the atmospheres and surfaces of various bodies within the solar system. The complex mixtures encountered place a heavy burden on the analytical instrumentation to detect and identify all species present. The minimal resources available onboard for such missions mandate that the instruments provide maximum analytical capabilities with minimal requirements of volume, weight and consumables. The miniCIDEX instrument was developed for the chemical analysis of a cemetery environment. It combined a Gas Chromatograph (GC) with a helium based Ion Mobility Spectrometer (IMS) to fulfill the analytical requirements of a cemetery exobiology mission: universal response; ppb sensitivity; low mass, volume and consumable MiniCIDEX is now a candidate for the chemical analysis instrument of a Titan Aero-rover Mission. The complexity of the analyses will be similar to the comet application with a heavier emphasis on organic molecules. Because the Titan Aero-Rover will be a balloon powered rover, much more attention is placed on the total mass of the instrument package. The GC will likely be a Micro-Electro-Mechanical-System (MEMS) design, smaller than the initial miniCIDEX GC by a factor of ten (with a similar reduction in consumable use). Similar miniaturization of the helium-based IMS will be necessary while maintaining the analytical capabilities. The two mission applications, the analytical requirements, and the evolution of the IMS design to accommodate these requirements will be presented.

Kojiro, Daniel R.↗

Multivariate Quantitative Chemical Analysis

Technique of multivariate quantitative chemical analysis devised for use in determining relative proportions of two components mixed and sprayed together onto object to form thermally insulating foam. Potentially adaptable to other materials, especially in process-monitoring applications in which necessary to know and control critical properties of products via quantitative chemical analyses of products. In addition to chemical composition, also used to determine such physical properties as densities and strengths.

Kinchen, David G.↗

Chemical Analysis of Fluorobenzenes via Multinuclear Detection in the Strong Heteronuclear J-Coupling Regime

Chemical analysis via nuclear magnetic resonance (NMR) spectroscopy using permanent magnets, rather than superconducting magnets, is a rapidly developing field. Performing the NMR measurement in the strong heteronuclear J-coupling regime has shown considerable promise for the chemical analysis of small molecules. Typically, the condition for the strong heteronuclear J-coupling regime is satisfied at µT magnetic field strengths and enables high resolution J-coupled spectra (JCS) to be acquired. However, the JCS response to systematic chemical structural changes has largely not been investigated. In this report, we investigate the JCS of C6H6−xFx (x = 0, 1, 2, …, 6) fluorobenzene compounds via simultaneous excitation and detection of 19F and 1H at 51.5 µT. The results demonstrate that JCS are quantitative, and the common NMR observables, including Larmor frequency, heteronuclear and homonuclear J-couplings, relative signs of the J-coupling, chemical shift, and relaxation, are all measurable and are differentiable between molecules at low magnetic fields. The results, corroborated by ab initio calculations, provide new insights into the impact of chemical structure and their corresponding spin systems on JCS. In several instances, the JCS provided more chemical information than traditional high field NMR, demonstrating that JCS can be used for robust chemical analysis.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

ISS Expeditions 16 Thru 20: Chemical Analysis Results for Potable Water

This slide presentation reviews the results of the chemical analysis of the potable water supply from the International Space Station (ISS) expeditions 16 thru 20. Both Russian ground water and shuttle-transferred water are available for the use of the ISS crew's requirements. This is supplemented with condensate water and water form the Water Recovery System (WRS). An overview of the condensate H2O recovery system is given and the WRS is described and diagrammed. The water quality requirements, the handling, and analytical methods for the inorganic and organic tests are reviewed. The chemical analysis results for expeditions 16-20 archival water samples collected from the various water sources indicate that all of the ISS potable water supplies were acceptable for crew consumption.

Straub, John E., II↗