Diffuse reflectance infrared fourier analyses

Diffuse reflectance infrared Fourier transform spectroscopy deuterium triglycine sulphate energy compensated atom probe energy dispersive analysis energy-loss near edge structure electron probe X-ray microanalysis elastic recoil detection analysis (see also FreS) electron spectroscopy for chemical analysis extended energy-loss fine structure field emission gun focused ion beam field ion microscope... 

The experimental system consists of three sections (i) a gas metering section with interconnected 4-port and 6-port valves, (ii) a reactor section including an in-situ diffused reflectance infrared Fourier transform spectroscopy reactor (DRIFTS) connected to tubular quartz reactor, (iii) an effluent gas analysis section including a mass spectrometer or a gas chromatograph (9). 

Pakdel H, Grandmaison JL, Roy C (1989) Analysis of wood vacuum pyrolysis solid residues by diffuse reflectance infrared Fourier transform spectrometry Can J Chem 67 310-314 Perkins WD (1986) Fourier transform-infrared spectroscopy Part I Instrumentation J Chem Educ 63 A5-A10... 

Castles, M.A. Azarraga, L.V. Carreira, L.A. Continuous on-line interface for reversed-phase microbore high performance liquid chromatography/diffuse reflectance infrared fourier transform analysis. Appl. Spectrosc. 1986, 40, 673-680. 

The catalysts were characterized by N2 adsorption-desorption isotherms, thermogravimetric analysis (TGA), temperature-programmed desorption of ammonia (NH3-TPD), X-ray diffraction (XRD), Raman spectroscopy, in-situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS), and X-ray photoelectron spectroscopy (XPS). The procedures and experimental conditions have been detailed elsewhere [9]. 

KJ Hartauer, ES Miller, JK Guillory. Diffuse reflectance infrared Fourier transform spectroscopy for the quantitative analysis of mixtures of polymorphs. Int J Pharm 85 163-174, 1992. 

Lennard C J, Mazzella W D and Margot P A 1993 Some applications of diffuse reflectance infrared Fourier transform spectroscopy DRIFTS in forensic science Analysis 21 M34-7... 

Accordingly, transient kinetic techniques which are able to provide unique information on the actual state of a working catalyst within a very short period of time [13,14] were applied to this complex and unstable catalytic system. Non-steady-state and steady-state isotopic transient kinetics (NSSTK and SSITK) combined with in situ diffuse reflectance infrared Fourier transformed spectroscopy (DRIFT) and temporal analysis of product (TAP) were performed in order to analyse some of the above mentioned key steps of the aromatisation process. 

IR spectroscopy is one of the few analytical techniques that can be used for the characterization of solid, liquid, and gas samples. The choice of sampling technique depends upon the goal of the analysis, qualitative identification or quantitative measurement of specific analytes, upon the sample size available, and upon sample composition. Water content of the sample is a major concern, since the most common IR-transparent materials are soluble in water. Samples in different phases must be treated differently. Sampling techniques are available for transmission (absorption) measurements and, since the advent of FTIR, for several types of reflectance (reflection) measurements. The common reflectance measurements are attenuated total reflectance (ATR), diffuse reflectance or diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS), and specular reflectance. The term reflection may be used in place of reflectance and may be more accurate specular reflection is actually what occurs in that measurement, for example. However, the term reflectance is widely used in the literature and will be used here. 

Our intention in this report is to demonstrate the utility of diffuse reflectance infrared Fourier transform (DRIFT) spectroscopy for coal analysis, particularly in relation to monitoring the in situ oxidation of coal, and to compare its relative merits to those of the KBr pellet and PA sampling techniques. 

Diffuse reflectance or DRIFTS (diffuse reflectance infrared Fourier-lransform spectroscopy) allows the sain)le to be analysed neat, ot diluted in a non-absorbing matrix (e.g. KCl or KBr at 1-5% w/w analyte). DRIFTS also may be used to obtain the spectrum of a solute in a volatile solvent by evaporating the solution onto KBr. When the IR radiation interacts with the powdered sample it will be absorbed, reflected and diffracted. The radiation which has been diffusely reflected contains vibrational information on the molecule. This technique allows non-destructive testing of neat materials and is suited to quantitative analysis, although care must be taken to ensure that a consistent particle size is used. 

The primary components and the chemical structure of the raw peat and the solid product were further analyzed by Fourier transform infrared spectroscopy (FTIR) 0ASCO 670 Plus) using the Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFTS) technique and the JASCO IR Mentor Pro 6.5 software for spectral analysis. The cross polarization/magic angle spinning (CP/MAS) NMR spectrum of raw peat and the solid... 

Adsorbent materials have been characterized and tested using a range of techniques. Characterisation of materials has focused on deteiming the physical and chemical properties of the sold sorbent materials. This has heen conducted using a range of techniques, for example, elemental analysis, power x-ray diffraction (XRD), diffuse reflectance infrared Fourier transform spectra (DRIFTS), textural properties have been determined by BET N2 adsorption analysis. Thermogravimetric analysis (TGA) has been used to determine the thermal stability of the materials as well as measure CO2 adsorption capacity and cyclic capacity [14]. 

Diffuse reflection spectroscopy, also known as diffuse reflectance infrared Fourier transform (DRIFT) spectroscopy, enables the analysis of many samples for which traditional techniques fail, to be made with little or no sample preparation. Many substances in their natural. state. e.spe-cially powders but also any solid with a rough surface, such as dyed textiles and printed papers, exhibit diffuse reflection, i.e., incident light is... 

B.K. Alsberg. W.G. Wade and R. Goodacre. Chemometric Analysis of Diffuse reflectance-absorbance Fourier Transform Infrared Spectra Using Rule Induction Methods Application to the Classification of Eubacterium Species, Applied Spectroscopy, 52(6) (1998), 823-832. 

In this contribution, the steady-state isotopic transient kinetic analysis-diffuse reflectance Fourier transform spectroscopy (SSITKA-DRIFTS) method provides further support to the conclusion that not only are infrared active formates likely intermediates in the water-gas shift (WGS) reaction, in agreement with the mechanism proposed by Shido and Iwasawa for Rh/ceria, but designing catalysts based on formate C-H bond weakening can lead to significantly higher... 

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