Detectors deuterated triglycine sulfate

The infrared absorption spectrum of atorvastatin calcium, Form-I, was obtained using a Nicolet FT-IR Impact 410 spectrophotometer equipped with deuterated triglycine sulfate detector, and using Omnic 5.1 a software. The sample was contained in a pressed KBr pellet, with each spectrum being derived from 16 single scans over the range of 4000-400 cm-1 at a... 

Figure 7.2. Transient time-resolved transmission IR spectra of pulsed injection of 1 cm of CO into 10 cm min CO, 10 cm min" NO, and 15 cm min He flow with 2% Ar during NO-CO reaction over 4 wt % Rh-Si02 at 473 K and 0.1 MPa. Spectra measured with resolution of 4 cm" using Nicolet 5SXC equipped with DIGS (deuterated triglycine sulfate) detector and in situ cell shown in Fig. 4.40, by averaging two or four scans. Reprinted, by permission, from S. S. C. Chuang, M. A. Brundage, M. W. Balakos, and G. Srinivas, Appl Spectrosc. 49,1151 (1995), p. 1161, Fig. 6b. Copyrighf 1995 Society for Applied Spectroscopy.

The system applied in the study mentioned previously consisted of a CDS model 122 Pyroprobe with a ribbon filament as the heating surface. This pyrolyser heats by varying the resistance of the platinum element. Temperature rise times for flash pyrolysis are typically of the order of milliseconds. IR spectra were obtained with an FT-IR bench system equipped with a CDS pyrolysis/FT-IR interface. The data were collected at 8 cm with a deuterated triglycine sulfate detector. The interface is cylindrical in shape with two potassium bromide windows for the IR beam to pass through. 

Pyroelectric detectors depend on the use of a thin slice of ferroelectric material (deuterated triglycine sulfate [DTGS], Figure 5.6, is the standard example) - in which the molecules of the organic crystal are naturally aligned with a permanent electric dipole. The thin slab is cut and arranged such that the direction... 

ETIR Measurements. FTIR spectra were recorded using a Nicolet model 870 spectrometer (Madison, WI) equipped with a deuterated triglycine sulfate (DTGS) detector. 

Deuterated triglycine sulfate (abbreviated DTGS) is a common ferroelectric infrared detector material. Explain how it works. 

FTIR Spectroscopy. Infrared spectra were recorded on a Perkin Elmer Spectrum One FTIR spectrometer equipped with a Deuterated Triglycine Sulfate (DTGS) detector and KBr optics. Data collection was performed at 4 cm-1 spectral resolution in the region of 4000-450 cm-1 and averaged over 5 scans. All samples were measured in transmission mode. 

A technique which has proven useful for our studies is that of cylindrical internal reflectance (CIR), coupled with a Fourier transform infrared spectrometer. In this study, an IBM-85 FTIR equipped with either a DTGS (deuterated triglycine sulfate) or MCT (mercury-cadmium-tellurium) detector was used. The infrared radiation is focused by concave mirrors onto the 45° conical ends of a transmitting crystal (Figure 1). The crystal may be made of any material which is optically transparent, has a high mechanical strength and high index of refraction, and is resistant to thermal shock and chemical attack. Suitable materials include ZnS, ZnSe,... 

The pyroelectric detector contains a mono-crystal of deuterated triglycine sulfate (DTGS) or lithium tantalate (LiTaOj), sandwiched between two electrodes, one of which is semi-transparent to radiation and receives the impact of the optical beam. It generates electric charges with small temperature changes. The crystal is polarized proportionally to the radiation received and it acts as a capacitor. 

Fourier transform mid-infrared (FTIR), near-infrared (FTNIR), and Raman (FT-Raman) spectroscopy were used for discrimination among 10 different edible oils and fats, and for comparing the performance of these spectroscopic methods in edible oil/fat studies. The FTIR apparatus was equipped with a deuterated triglycine sulfate (DTGS) detector, while the same spectrometer was also used for FT-NIR and FT-Raman measurements with additional accessories and detectors. The spectral features of edible oils and fats were studied and the unsaturation bond (C=C) in IR and Raman spectra was identified and used for the discriminant analysis. Linear discriminant analysis (LDA) and canonical variate analysis (CVA) were used for the disaimination and classification of different edible oils and fats based on spectral data. FTIR spectroscopy measurements in conjunction with CVA yielded about 98% classification accuracy of oils and fats followed by FT-Raman (94%) and FTNIR (93%) methods however, the number of factors was much higher for the FT-Raman and FT-NIR methods. 

The middle infrared (MIR) spectra were obtained with FTIR spectrometers (Nicolet 60SX, resolution = 2 cm Perkin Elmer System 2000, resolution 2cm , both the spectrometers equipped with deuterated triglycine sulfate, DTGS, detector), either by transmission through self-supporting silica disks or from diffuse reflectance of silica powder. Silica disks pressed under 50 MPa could be evacuated with a residual pressure under 10 Pa. The spectra are shown in a normalized absorbance scale, according to... 

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