Infrared Emission Spectroscopy. I. Basic Considerations

1972 ◽  
Vol 26 (1) ◽  
pp. 73-76 ◽  
Author(s):  
Peter R. Griffiths
Keyword(s):  
High Pressure ◽  
Emission Spectroscopy ◽  
Infrared Emission ◽  
Thin Layers ◽  
Surface Films ◽  
Silicone Grease ◽  
Basic Principles ◽  
Ir Emission ◽  
Thick Layers

The basic principles behind the characterization of compounds by ir emission spectroscopy have been illustrated using surface films of silicone grease and gaseous samples. Anomalous features in the spectra are accounted for by considering the absorption of emitted radiation by less thermally excited molecules in the path to the detector. It is suggested that ir emission spectroscopy can be used easily to characterize thin layers on heated specular mirrors or hot vapors at low pressure, but care must be taken in the interpretation of results for thick layers of gases at high pressure, when the temperature of the emitter is close to that of the detector, or when molecules are to be characterized on substrates whose emissivity is high.

scholarly journals Synthesis and Characterization of Boehmite Nanofibers

2008 ◽  
Vol 2008 ◽  
pp. 1-4 ◽  
Author(s):  
Jing Yang ◽  
Ray L. Frost
Keyword(s):  
Emission Spectroscopy ◽  
Analytical Techniques ◽  
Infrared Emission ◽  
Synthesis And Characterization ◽  
X Ray Diffraction ◽  
High Quality ◽  
X Ray ◽  
Clear Cut ◽  
Scanning Electron

Boehmite nanofibers of high quality were synthesized through a wet-gel conversion process without the use of a surfactant. The long nanofibers of boehmite with clear-cut edges were obtained by steaming the wet-gel precipitate at 170∘C for 2 days. Analytical techniques such as X-ray diffraction (XRD), scanning electron microscopy (SEM), infrared emission spectroscopy (IES), as well as Raman spectroscopy were used to characterize the products.

Infrared Emission Spectroscopy of Coal Minerals and Their Thermal Transformations

1992 ◽  
Vol 46 (1) ◽  
pp. 73-78 ◽  
Author(s):  
A. M. Vassallo ◽  
P. A. Cole-Clarke ◽  
L. S. K. Pang ◽  
A. J. Palmisano
Keyword(s):  
Fourier Transform ◽  
Emission Spectrum ◽  
Atomic Absorption ◽  
Emission Spectroscopy ◽  
Graphite Furnace ◽  
Infrared Emission ◽  
Thermal Transformations ◽  
Infrared Spectrometer ◽  
Ir Emission

An infrared (IR) emission cell which is capable of operation up to 1500°C is described. The cell is based on an atomic absorption graphite furnace and is coupled to a Fourier transform infrared spectrometer. The spectrometer has been used to measure the emission spectrum of quartz from 200 to 1400°C, and the changes in the spectrum occurring with temperature can be related to the formation of cristobalite; transitions between low and high forms (alpha and beta forms) can also be monitored. Aragonite has also been analyzed through the temperature range 100 to 600°C, and the aragonite/calcite transition is clearly evident. The transformation of kaolinite to metakaolinite and through to mullite and cristobalite has also been studied with this in situ technique. The formation of mullite is evident in the spectrum at temperatures as low as 900°C, and the formation of cristobalite is clearly seen at 1200°C.

FT-IR Emission Spectroscopy and its Applications

1993 ◽  
Vol 47 (9) ◽  
pp. 1446-1451 ◽  
Author(s):  
János Mink ◽  
Gábor Keresztury
Keyword(s):  
Emission Spectroscopy ◽  
Emission Spectra ◽  
Infrared Emission ◽  
Metal Powders ◽  
Adsorbed Species ◽  
Infrared Emission Spectroscopy ◽  
Recent Developments ◽  
Ft Ir ◽  
Ir Emission

The practical aspects of infrared emission spectroscopy are reviewed briefly, with emphasis on recent developments and on special problems encountered in measurements of adsorbed species on opaque substrates. A few examples are given for cases when the species of interest give rise to inverted emission bands on the background of substrate emission. The feasibility of recording IR emission spectra of adsorbates on metal powders is demonstrated.

Characterization of Microwave Plasma for Polymer Surface Modification Using FTIR Emission Spectroscopy

2011 ◽  
Vol 409 ◽  
pp. 797-801 ◽  
Author(s):  
Maryam Mavadat ◽  
Stéphane Turgeon ◽  
André Ricard ◽  
Gaetan Laroche
Keyword(s):  
Emission Spectroscopy ◽  
Microwave Plasma ◽  
Polymer Surface ◽  
Plasma Temperature ◽  
Infrared Region ◽  
Emission Data ◽  
Numerical Generation ◽  
Ir Emission ◽  
Microwave Discharges

Infrared (IR) emission spectroscopy measurements were performed in N2 microwave discharges at pressures ranging from 0.5 to 3 Torr and powers of 200 and 300 W. Although emission spectroscopy in the infrared region has rarely been investigated, this technique has nevertheless provided numerous key data. For instance, numerical generation of spectra to match experimental FTIR emission data allowed estimating the plasma temperature.

Single Photon Infrared Emission Spectroscopy:  A Study of IR Emission from UV Laser Excited PAHs between 3 and 15 μm

1998 ◽  
Vol 102 (9) ◽  
pp. 1465-1481 ◽  
Author(s):  
D. J. Cook ◽  
S. Schlemmer ◽  
N. Balucani ◽  
D. R. Wagner ◽  
J. A. Harrison ◽  
...  
Keyword(s):  
Emission Spectroscopy ◽  
Single Photon ◽  
Infrared Emission ◽  
Uv Laser ◽  
Infrared Emission Spectroscopy ◽  
Ir Emission

Infrared Emission Spectroscopy as a Reliability Tool

1999 ◽  
Author(s):  
Q. Kim ◽  
S. Kayali
Keyword(s):  
Spatial Resolution ◽  
Emission Spectroscopy ◽  
Hot Spot ◽  
Cost Effective ◽  
Infrared Emission ◽  
Test System ◽  
Operating Conditions ◽  
Yield Enhancement ◽  
Infrared Emission Spectroscopy ◽  
Channel Temperature

Abstract In this paper, we report on a non-destructive technique, based on IR emission spectroscopy, for measuring the temperature of a hot spot in the gate channel of a GaAs metal/semiconductor field effect transistor (MESFET). A submicron-size He-Ne laser provides the local excitation of the gate channel and the emitted photons are collected by a spectrophotometer. Given the state of our experimental test system, we estimate a spectral resolution of approximately 0.1 Angstroms and a spatial resolution of approximately 0.9 μm, which is up to 100 times finer spatial resolution than can be obtained using the best available passive IR systems. The temperature resolution (<0.02 K/μm in our case) is dependent upon the spectrometer used and can be further improved. This novel technique can be used to estimate device lifetimes for critical applications and measure the channel temperature of devices under actual operating conditions. Another potential use is cost-effective prescreening for determining the 'hot spot' channel temperature of devices under normal operating conditions, which can further improve device design, yield enhancement, and reliable operation. Results are shown for both a powered and unpowered MESFET, demonstrating the strength of our infrared emission spectroscopy technique as a reliability tool.

Separation and Characterization of Standard Propoxyphene Diastereomers and Their Determination in Pharmaceutical and Illicit Preparations

1981 ◽  
Vol 64 (4) ◽  
pp. 875-883
Author(s):  
Shiv K Soni ◽  
Daniel Van Gelder
Keyword(s):  
High Pressure ◽  
Optical Isomers ◽  
Gold Chloride ◽  
Melting Points ◽  
Eutectic Melting ◽  
Racemic Mixtures ◽  
The Individual ◽  
Isomeric Mixtures ◽  
Asymmetric Carbon

Abstract Due to the existence of 2 asymmetric carbon atoms in: the propoxyphene molecule, there are 4 diastereomers: alpha dextro, alpha levo, beta dextro, and beta levo. Only α-d-propoxyphene is included under the federal Controlled Substances Act. Baseline separations of propoxyphene from various incipients (aspirin, caffeine, phenacetin, and acetaminophen) present in pharmaceutical and illicit preparations, and between the alpha and beta diastereomers, were achieved by high pressure liquid chromatography. The column eluant was collected and propoxyphene was extracted. The optical isomers were differentiated and characterized by melting points and by chemical microcrystalline tests. Using hot stage thermomicroscopy, the eutectic melting points of binary isomeric mixtures of propoxyphene bases and salts were found to be depressed about 10° and 15-30°C, respectively, below the individual isomer melting points. The characteristic microcrystals formed with the alpha racemic mixtures by using a glycerin-aqueous gold chloride reagent were not produced by the beta racemic mixtures.

The Use of Ratio-Recording Interferometry for the Measurement of Infrared Emission Spectra: Applications to Oxide Films on Copper Surfaces

1975 ◽  
Vol 29 (6) ◽  
pp. 496-500 ◽  
Author(s):  
D. Kember ◽  
N. Sheppard
Keyword(s):  
Emission Spectra ◽  
Black Body ◽  
Infrared Emission ◽  
Thin Layers ◽  
Oxide Surface ◽  
Surface Layers ◽  
Selective Reflection ◽  
Copper Surfaces ◽  
Emission And Absorption Spectra ◽  
Direct Correspondence

Infrared emission spectra from metal samples with oxide surface layers are shown to be very advantageously studied using the spectrum-ratioing facility of a recording infrared interferometer. The emission from a given sample is ratioed against that from a black-body emitter at the same temperature so as to give emittance as a function of wavenumber directly. This method has very useful application to irregularly shaped metal emitters. In the absence of selective reflection there is a direct correspondence between emission and absorption spectra for thin layers of an emitting substance. However, the presence of selective reflection leads to reduced emission and to considerable differences in the appearance of “absorption” and emission spectra in regions of strong absorption. Emission spectra obtained from copper plates heated, above 150°C, for different periods in air are shown clearly to indicate the presence of cuprous, Cu(I), and cupric, Cu(II), oxides in the surface layer.

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