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Optical infrared

When the spectral characteristics of the source itself are of primary interest, dispersive or ftir spectrometers are readily adapted to emission spectroscopy. Commercial instmments usually have a port that can accept an input beam without disturbing the usual source optics. Infrared emission spectroscopy at ambient or only moderately elevated temperatures has the advantage that no sample preparation is necessary. It is particularly appHcable to opaque and highly scattering samples, anodized and painted surfaces, polymer films, and atmospheric species (135). The interferometric... [Pg.315]

Telephone cable Pneumatic Optical fibre Optical - infrared Radio... [Pg.329]

Keywords detectors, optical, infrared, quantum efficiency, noise... [Pg.123]

Figure 4. Simplified schematic of an optical/infrared focal plane array. The detector is a thin wafer of light sensitive material that is connected to a thin layer of solid state electronics - the connection is made either by direct deposition (CCD) or bump bonding (IR detector). The solid state electronics amplify and read out the charge produced by the incident light. Figure 4. Simplified schematic of an optical/infrared focal plane array. The detector is a thin wafer of light sensitive material that is connected to a thin layer of solid state electronics - the connection is made either by direct deposition (CCD) or bump bonding (IR detector). The solid state electronics amplify and read out the charge produced by the incident light.
In this study, we extend the range of inorganic materials produced from polymeric precursors to include copper composites. Soluble complexes between poly(2-vinylpyridine) (P2VPy) and cupric chloride were prepared in a mixed solvent of 95% methanol 5% water. Pyrolysis of the isolated complexes results in the formation of carbonaceous composites of copper. The decomposition mechanism of the complexes was studied by optical, infrared, x-ray photoelectron and pyrolysis mass spectroscopy as well as thermogravimetric analysis and magnetic susceptibility measurements. [Pg.430]

Optical, infrared, x-ray, thermal, and chemical studies were carried out to characterize the anthraxolite and to determine its geochemical evolution. Some differences in the same properties were noted for different nodules hence, several nodules were pulverized together in order to have average anthraxolite for analyses. Sufficient material for determining compositional extremes and variation was not available. Present understanding suggests that neither properties nor composition vary widely. [Pg.103]

In a Si zero-dimensional system the strong quantum confinement can increase the optical infrared gap of bulk Si and consequently shift the optical transition energies towards the visible range [65,66]. This is the reason for which silicon nanocrystals (Si-NCs) with a passivated surface are used as the natural trial model for theoretical simulations on Si based light emitting materials, such as porous Si or Si nanocrystals dispersed in a matrix. In this section we present a comprehensive analysis of the structural, electronic and optical properties of Si-NCs as a function of size, symmetry and surface passivation. We will also point out the main changes induced... [Pg.216]

In a few cases, small optical infrared absorption monitors have been integrated into electronic nose sensors [11], mostly for detection of the carbon dioxide evolution from cells. The 3000-4000 nm filters are normally used. [Pg.68]

Corkill et al. [56] have used for the first time the infrared spectroscopy for foam films. The measurement of the adsorption of the infrared light provides information about the water content in the foam films which is of major significance for the black foam films. These studies involved the use of dispersion type instruments. In order to obtain measurable values of adsorption, the infrared light is passed through a series of vertical films (up to 10) formed in a cylindrical tube acting as a frame. Additional information about the film structure the authors derived from the correlation between the optical infrared transmission data and the film reflectance measurements. Here a three-layer model of the film structure consisting of an aqueous core sandwiched between two adsorption layers is assumed (see Section 2.1.3). [Pg.71]

Nonlinear optical infrared-visible sum frequency generation (IR-vis SFG) is a versatile surface-specific vibrational spectroscopy that meets the requirements mentioned above. SFG provides vibrational spectra of molecules adsorbed on a surface, while the molecules in the gas phase do not produce a signal. Consequently, SFG can be operated in a pressure range from UFIV to ambient conditions and still detects only the adsorbed species. A direct comparison of adsorbate structures under UFIV and elevated pressure is therefore feasible. Furthermore, SFG can be applied to molecules adsorbed on single crystals, thin films, metal foils, and supported nanoparticles (46,116-121) and is thus a promising tool to extend surface science experiments to more realistic conditions. [Pg.144]

Fig. 11. Experimental setup for the in situ detection of chemisorbed CO during catalytic combustion of CO on Pt using optical infrared-visible sum frequency generation (SFG) and mass spectrometry. A mode-locked Nd YAG laser system is used to provide the visible laser beam (second harmonic 532 nm) and to pump an optical parametric system to generate infrared radiation (wir) tunable with a pulse duration of 25 ps. MC monochromator, PMT Photomultiplier, AES Auger Electron Spectrometer, LEED Low Energy Electron Diffraction Spectrometer, QMS Quadrupole Mass Spectrometers for CO Thermal Desorption (TD) and CO2 production rate measurements. Fig. 11. Experimental setup for the in situ detection of chemisorbed CO during catalytic combustion of CO on Pt using optical infrared-visible sum frequency generation (SFG) and mass spectrometry. A mode-locked Nd YAG laser system is used to provide the visible laser beam (second harmonic 532 nm) and to pump an optical parametric system to generate infrared radiation (wir) tunable with a pulse duration of 25 ps. MC monochromator, PMT Photomultiplier, AES Auger Electron Spectrometer, LEED Low Energy Electron Diffraction Spectrometer, QMS Quadrupole Mass Spectrometers for CO Thermal Desorption (TD) and CO2 production rate measurements.
In the Fall of 1999, a set of field tests were conducted at Fallon Naval Air Station to study the optical infrared signatures arising from the detonation of conventional munitions. Three types of explosives (A, B and C) spanning several weights (extra small. [Pg.278]

Ultraprecise surface figuring (e.g., optics with accuracy in the nm scale, i.e., stepper optics, x-ray-optics, infrared optics, diffractive optics, laser mirrors). [Pg.216]

This paper describes ongoing studies of the electrodeposition thin films of the compound semiconductors CdTe and InAs, using the method of electrochemical atomic layer epitaxy (ALE). Surface limited electrochemical reactions are used to form the individual atomic layers of the component elements. An automated electrochemical flow deposition system is used to form the atomic layers in a cycle. Studies of the conditions needed to optimize the deposition processes are underway. The deposits were characterized using X-ray diffraction, scanning probe microscopy, electron probe microanalysis and optical/infrared absorption spectroscopy. [Pg.272]

Figure 6. Infrared-NSOM image of a blended polystyrene/polyethylacrylate film ( 1 micron thick) on Si. The image (8 /xm X 8 /xm), collected at 3125 cm b shows the domains of polystyrene (PS) embedded within the polyethylacrylate (PEA). This chemical map of the surface has 10 times higher spatial resolution than a conventional optical infrared microscope image. (Courtesy of Dr. Chris Michaels and Dr. Stephan Stranick, NIST.)... Figure 6. Infrared-NSOM image of a blended polystyrene/polyethylacrylate film ( 1 micron thick) on Si. The image (8 /xm X 8 /xm), collected at 3125 cm b shows the domains of polystyrene (PS) embedded within the polyethylacrylate (PEA). This chemical map of the surface has 10 times higher spatial resolution than a conventional optical infrared microscope image. (Courtesy of Dr. Chris Michaels and Dr. Stephan Stranick, NIST.)...
Table 1. Experimental Electro-optical Infrared Intensity Parameters for Butadiene and trans Polyacetylene. Table 1. Experimental Electro-optical Infrared Intensity Parameters for Butadiene and trans Polyacetylene.
The results are presented of an investigation of the optical infrared transmission and reflection spectra of the alloy 0.7 InSb-0.3 InAs, doped with tellurium to obtain different electron densities (n). The optical width of the forbidden band (AE) and the optical effective mass of the electrons (mn) were determined from the spectra and their dependence on n studied. It was established that the conduction bands of InSb-InAs solid solutions are nonparabolic. Attempts were made by extrapolation to obtain an estimate of the limiting values of AE and mg in the region of low values of n, and an estimate of the matrix element P was made. It is concluded that there is general agreement between the structure of the energy bands of the semiconductor alloys considered and the Kane model. [Pg.45]

The optical (infrared and visible) thresholds are described by complex dielectric constants, which accounts for the shape of the polarizability curve at these frequencies. [Pg.149]

The most conventional method to determine methanol crossover in a DMFC is to monitor the CO2 content in the cathode exhaust gas flux by using an optical infrared sensor, by gas chromatographic analysis, or by mass spectrometry [132], However, these measurements are based on the assumptions that flie crossed over methanol at the cathode is completely oxidized and that there is no CO2 permeation from the anode to the cathode. In reality, in particular for operation at high current density, a large amount of CO2 permeates from the anode to the cafliode in the DMFC. So far, no reliable method is available to measure the methanol crossover through the membrane from the anode to the cathode at the operating status. [Pg.48]


See other pages where Optical infrared is mentioned: [Pg.1960]    [Pg.430]    [Pg.4]    [Pg.80]    [Pg.273]    [Pg.171]    [Pg.488]    [Pg.1517]    [Pg.6]    [Pg.412]    [Pg.3]    [Pg.178]    [Pg.200]    [Pg.530]    [Pg.31]    [Pg.42]    [Pg.1960]    [Pg.151]    [Pg.72]    [Pg.183]    [Pg.379]    [Pg.60]    [Pg.117]    [Pg.3880]    [Pg.184]    [Pg.166]    [Pg.1145]    [Pg.428]   
See also in sourсe #XX -- [ Pg.64 , Pg.68 , Pg.219 ]




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Fourier Transform-infrared Optical microscope

Fourier transform infrared optical system

Infrared and Fiber-Optic Thermometers

Infrared and optical spectra

Infrared optics

Infrared optics

Infrared spectrometer optical components

Infrared spectrometer optical systems

Infrared spectroscopy optical materials

Near infrared optics

Near infrared regions, glass optical fibers

Near-infrared spectrometers optical-filter spectrometer

Near-infrared spectroscop optical fibers used

Optical Components Used in Infrared Spectrometers Specially Designed for External Reflectance Spectroscopy

Optical Spectroscopy in the Infrared Range

Optical and Infrared Properties

Optical birefringence and infrared activation

Optical fibers near-infrared

Optical properties strong near-infrared absorption

Optical properties, spectroscopy infrared

Optical systems infrared

Optical techniques infrared absorption spectra

Strong infrared absorption, dithiolene optical properties

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