Chemical characterization Fourier transform infrared spectroscopy

Field desorption mass spectrometry [1606], C nuclear magnetic resonance, and fourier-transform infrared spectroscopy [1337] have been used to characterize oil field chemicals, among them, scale inhibitors. Ion... 

Willis, J. N. and Wheeler, L., Use of a gel permeation chromatography-Fourier transform infrared spectroscopy interface for polymer analysis, in Chromatographic Characterization of Polymers, Hyphenated and Multidimensional Techniques, Provder, T., Barth, H. G., and Urban, M. W., Eds., American Chemical Society, Washington, D.C., 1995, chap. 19. 

The wavelengths of IR absorption bands are characteristic of specific types of chemical bonds. In the past infrared had little application in protein analysis due to instrumentation and interpretation limitations. The development of Fourier transform infrared spectroscopy (FUR) makes it possible to characterize proteins using IR techniques (Surewicz et al. 1993). Several IR absorption regions are important for protein analysis. The amide I groups in proteins have a vibration absorption frequency of 1630-1670 cm. Secondary structures of proteins such as alpha(a)-helix and beta(P)-sheet have amide absorptions of 1645-1660 cm-1 and 1665-1680 cm, respectively. Random coil has absorptions in the range of 1660-1670 cm These characterization criteria come from studies of model polypeptides with known secondary structures. Thus, FTIR is useful in conformational analysis of peptides and proteins (Arrondo et al. 1993). 

Infrared spectroscopy (IR) or Fourier transform infrared spectroscopy (FTIR) are often used to characterize BN products. If pure BN mixtures with B N ratio of 1 1 are analyzed, it will be easy to distinguish between h-BN and c-BN. However, if the chemical composition of the sample is unknown, many artifacts can occur and a clear statement is often not possible. 

Characterization. The PPNVP and PPNVP/PEUU films were characterized by attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), electron spectroscopy for chemical analysis (ESCA), ellipsometry, and water contact angles in air. Two independent methods, a modification of the radioimmunoassay used by Ziats, et. al. (14) and an immunochemical stain based on the ABC immunohistochemical staining method (15) were developed to assay the binding of GOx to the PPNVP/PEUU support. 

V. A. Maroni and J. R. Ferraro, The use of vibrational spectroscopy in the characterization of high-critical temperature ceramic superconductors, in Practical Fourier Transform Infrared Spectroscopy—Industrial Laboratory Chemical Analysis (J. R. Ferraro and K. Krishnan, eds.). Academic Press, San Diego (1990), and references therein. 

Swalen JD, Rabolt JF (1985) Characterization of Orientation and Lateral Order in Thin Films by Fourier Transform Infrared Spectroscopy. In Ferraro JR, Basile LJ (eds) Fourier Transform Infrared Spectroscopy, Applications to Chemical Systems. Academic. Orlando, p 283 Swanson BI, Jones LH (1981) J Mol Spectrosc 89 566 Sweger DM, Travis JC (1979) AppI Spectrosc 33 46 Swietlik R, Schweitzer D, Keller HJ (1987) Phys Rev B6 881... 

There are several experimental techniques available to study the chemical properties of clusters on surfaces and when used in combination, a detailed picture can be obtained. A classical approach is the use of temperature programmed desorption (TPD) and temperature programmed reaction (TPR) spectroscopy [39, 239,240] in combination with temperature-dependent and eventually time-dependent Fourier transformed infrared spectroscopy (FTIR) [39,192,241-244]. This combination allows for obtaining information on estimates of binding energies of reactant molecules (TPD), for characterizing... 

Characterization of catalysts The zeolite structure was checked by X-ray diffraction patterns recorded on a CGR Theta 60 instrument using Cu Ka, filtered radiation. The chemical composition of the catalysts was determined by atomic absorption analysis after dissolution of the sample (SCA-CNRS, Solaize, France). Micropore volumes were measured by N2 adsorption at 77 K using a Micromeritics ASAP 2000 apparatus and by adsorption of cyclohexane (at P/Po=0.15) using a microbalance apparatus SET ARAM SF 85. Incorporation of tetrahedral cobalt (II) in the framework of Co-Al-BEA and Co-B-BEA was confirmed by electronic spectroscopy [18] using a Perkin Elmer Lambda 14 UV-visible diffuse reflectance spectrophotometer. Acidity measurements were performed by Fourier transform infrared spectroscopy (FT-IR, Nicolet FTIR 320) after pyridine adsorption. Self-supported wafer of pure zeolite (20 mg/cm ) was outgassed at 673 K for 6 hours at a pressure of lO Pa. After cooling at 423 K, the zeolite was saturated with pyridine vapour (30 kPa) for 5 min, evacuated at this temperature for 30 min and the IR spectrum was recorded. 

Zeltner, W. A., E. C. Yost, M. L. Machesky, M. I. Tejedor-Tejedor, and M. A. Anderson (1986), Characterization of Anion Binding on Goethite Using Titration Calorimetry and Cylindrical Internal Reflection Fourier Transform Infrared Spectroscopy, Geochemical Processes at Mineral Surfaces, J. A. Davis and K. F. Hayes, Eds. (ACS Symposium Series No. 323), American Chemical Society, Washington, DC. 

The spent catalysts were characterized by chemical analysis (carbon content), temperature programmed oxidation coupled to a mass spectrometer (TPO/MS) and thermal analysis (DTA and TG). The samples were also submitted to extraction of soluble coke in a soxhiet apparatus with n-hexane and dichloromethane for 24h, after being treated with fluoridric acid (40%) at room temperature (2h), followed by reflux with hydrocloric acid (36%) for 2h. The extracts were analyzed by gas-chromatography-mass spectrometry (GC/MS), Fourier transformer infrared spectroscopy (FTIR), ultraviolet spectroscopy (UV) and X ray diffraction. The insoluble fraction was analyzed by X ray diffraction and FTIR. 

Due to the fundamental importance of the adsorbed protein film, many methods have been used to characterize its nature. These methods include ellipsometry (3,A), Fourier transform infrared spectroscopy (FTIR) (5,6), multiple attenuated internal reflection spectroscopy (MAIR) (7,8) immunological labeling techniques (9), radioisotope labeled binding studies (j ), calorimetric adsorption studies (jj ), circular dichroism spectroscopy (CDS) (12), electrophoresis (j ), electron spectroscopy for chemical analysis (ESCA) (1 ), scanning electron microscopy (SEM) (15,16,9), and transmission electron microscopy (TEM) (17-19). 

Framework and Surfaces Since compositions and structures are very diverse, surface and framework properties are also extremely varied. In terms of compositions, coordination, and chemical environments, several methods are particularly informative for the characterization of nanoporous solids, such as nuclear magnetic resonance methods (NMR), UV-visible spectroscopy, Fourier-transform infrared spectroscopy (FTIR), Raman spectroscopy, x-ray absorption spectroscopies, x-ray photoelectron emission spectroscopy (XPS), and electron paramagnetic resonance (EPR) (4, 6). Among them, sohd state NMR techniques arc largely employed and will be briefly described in the following. 

Other physical properties, such as air permeability, interfiber pore size and porosity, were also studied. Activated carbon nanofibers were produced from eleetrospun PAN by chemical activation with potassium hydroxide (KOH) as the activating agent. They were characterized by morphology, Fourier transform infrared spectroscopy (FTIR), Brunauer-Emmett-Teller... 

Klebsiella pneumonia KYCC 4352, co//ATCC10536, and . aureus ATCC 6538 were the three different bacteria with gram-postive and gram-negative characteristics that were selected to determine the antimicrobial activity of nanofibrous webs made from PVP/ CTAB salt. A detailed chemical characterization was performed on the produced nanofibrous webs by carrying out Fourier transform infrared spectroscopy (FTIR], ultraviolet visible (UV-Vis], and electrochemical impedance spectroscopy (EIS] measurements. ... 

Chemical characterization of the UHMWPE powder is typically performed at the powder-manufacturing site as part of their quality control protocol. However, researchers may want to periodically verify the purity and composition of the powder. ASTM 648 outlines several tests that can be used to analyze the powder. With regards to chemical characterization, trace element analysis and Fourier transform infrared spectroscopy (FTIR) are the two common approaches. 

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