Chemical structure analysis

Light element spectroscopy for concentration, electronic, and chemical structure analysis at ultra-high lateral resolution in a TEM or STEM... 

Schuffenhauer A, Gillet VJ, Willett P. Similarity searching in files of 3D chemical structures analysis of the BIOSTER database using 2D fingerprints and molecular field descriptors. J Chem Inf Comput Sci 2000 40 295-307. 

Our solution to this problem was the development of an interactive computer system that can be used by all professionals in the company to locate and manipulate chemical information. This system is called MAECIS, an acronymn for Management and Analysis Executive for Chemical Information and Structures. As the name implies, MAECIS is both a chemical information storage system and a chemical structure analysis system. 

Compared to conventional white-light analysis, fluorescence microscopy reveals a greater number and variety of macerals, as well as, characteristic textures and structures. Although the spectra of fluorescent macerals are broad-peaked and, at this time, not suitable for chemical structure analysis, they are characteristic of maceral types and rank. 

Although the characterization of coal macerals on the basis of their fluorescence spectra is a recent innovation, it has already proven to be an excellent fingerprinting tool for the various macerals. In some cases, it is even more sensitive than normal petrographic analysis. The initial results of fluorescence spectral studies show that the various fluorescent macerals in single coals can be statistically discriminated on the basis of their spectral parameters and that even varieties of a single maceral type can be distinguished. Although the spectra obtained at this time are rather broad and not suitable for chemical structure analysis, the potential for structural analysis exists and may be realized with improvements in instrumentation. 

Chemical—structural analysis and leachability tests on scum, slag, and Fe-minerals were carried out to characterize and measure the chemical stability of the metals in waste materials. The investigation was designated to (1) evaluate the... 

N. Bourgougnon, M. Lahaye, B. Quimener, M. Cormaci, G. Fumari, and J.-M. Komprobst, Chemical structure analysis of water-soluble sulfated polysaccharide from Schizymenia dubyi (Rhodophyta, Gigartinales), J. Appl. Phycol., 8 (1996) 147-153. 

Dorothy Hodgkin, who obtained a Nobel Prize in 1965 for her X-ray diffraction work, wrote, a great advantage of X-ray analysis as a method of chemical structure analysis is its power to show some totally unexpected and surprising structure with, at the same time, complete certainty. Her X-ray diffraction studies are the reason that we now know that penicillin has a /3-lactam structure and that vitamin B, contains what is now known as a corrin ring system. The results of all X-ray diffraction studies are used by chemists and biochemists, and these scientists need to be able to appreciate the significance and extent to which such results are useful and precise. 

The crystal structure of as prepared samples was identified by using a powder X-ray diffractometer equipped with CuKa radiation (30kV, 20mA) and a monochromator. An infrared spectrometer was used for the chemical structure analysis. Chemical composition of samples was determined by EDX analysis. To determine the content of organic species in the composites, thermal gravimetric (TG) analysis was carried out at a heating rate of 10 °C/min in air. The BET surface area was determined by measuring N2 adsorption isotherms at 77 K. The microstructure of samples was observed by FE-SEM. Diffuse reflectance spectra were recorded with a UV-vis spectrometer. 

Chem. Inf. Comput. Sci., 43, 391-405. Schuffenhauer, A., Gillet, V.J. and Willett, P. (2000) Similarity searching in flies of three-dimensional chemical structures analysis of the BIOSTER database using two-dimensional flngerprints and molecular fleld descriptors. /. Chem. Inf. Comput. Sci., 40, 295-307. 

Micro and chemical structural analysis, including porosity, bonding, coking X-ray diffraction (XRD) Nuclear magnetic resonance (NMR) Fourier-transform infrared (FTIR) Scanning electron microscopy (SEM) Transmission electron microscopy (TEM) Atomic force microscopy (AFM) Raman spectroscopy Small probe molecule volumetric and gravimetric adsorption... 

CHEMICAL STRUCTURE ANALYSIS OF STARCH AND CELLULOSE DERIVATIVES 119... 

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