Characterization of structures and

Hendrickson, J.B. (1971) A Systematic Characterization of Structures and Reactions for Use in Organic Synthesis. Journal of the American Chemical Society, 93, 6847-6854. 

R. B. Ultrafiltration tandem mass spectrometry of estrogens for characterization of structure and affinity for human estrogen receptors. J. Am. Soc. Mass Spectrom. 2005, 16, 271-279. 

Various levels of structure ultimately determine the properties of a polymer. The characterization of structure and how it influences properties is outlined in the following. 

S.C. Reyes and E. Iglesia, Simulation techniques for the characterization of structural and transport properties of catalyst pellets, in Computer-Aided Design of Catalysts E.R. Becker, and C.J. Pereira, cds., Dekker, New York, 1993. 

Characterization of Structure and Microtexture of Carbon Materials by Magnetoresistance Technique, Yoshihiro Hishiyanui, Yiitaka Kahiiragi, and Michio Inagaki... 

In this review, we tried to highlight the possibilities of using NMR approaches for exploring phase transformations. The merit and achievements of NMR in the study of phase transitions is quite clear. Owing to its selectivity and sensitivity, NMR helps in discovering the existence of a transition, the identification of the different phases and the characterization of structural and dynamical order in the different phases. In favorable cases,... 

NMR has grown in importance over the last two decades as an important tool for characterizing the structure and dynamics of polymers, both synthetic and biosynthetic. Other reviews have appeared in the recent literature [1, 2]. This chapter will focus on both the characterization of structure and dynamics of biopolymers from spectra obtained without the use of magic-angle spinning. 

The characterization of structure and dynamics in metal carbonyl cluster chemistry has understandably been based around single-crystal X-ray diffraction and NMR spectroscopic studies, respectively. As has been shown in the earlier part of this chapter, these sources of data can be used in conjunction to provide a coherent picture of the possible molecular configurations of a given species and the processes by which they interconvert, at least in favorable cases. In general however, it is not possible to determine the geometric structures of these species in solution, nor to obtain direct experimental evidence to confirm that the same structure(s) obtain in solution as in the solid state. Fortunately the rebirth and exploitation of X-ray absorption spectroscopy (XAS) and in particular the application of synchrotron X-ray sources and improved methods of data analysis to EXAFS (Extended X-ray Absorption Eine Structure) spectroscopy has provided exactly this sort of experimental evidence. In this section we provide selective coverage of such work as relates to the structure and dynamics of metal carbonyl clusters. 

Characterization of structure and combustion behavior of the coke Formed on a hydroisomerization catalyst... 

Hinderberger D, Jeschke G (2006) Site-specific characterization of structure and dynamics of complex materials by EPR spin probes. Modem Magnetic Resonance 3 1509-1517... 

A less empirical approach to synthesis analysis has been taken by Hendrickson He recognizes the need for a system of characterization of structures and reactions that is specifically designed for use in synthesis. Obviously such a system should derive from the fundamentals of structure, and should be general enough to allow the inclusion of new reactions without collapse of the system. It should convey the information a chemist looks for first when he considers a molecule that is to be synthesized, i.e. the carbon skeleton and functionality. Finally, the system should be so designed that it takes into account, at least implicitly, all possible synthetic routes to a given compound. 

Stationary hanging mercury drop electrodes (h.m.d.e.) are suitable for evaluating a slow equilibrium of adsorption and subsequent reduction. Solid metal or graphite electrodes are used mainly for oxidation. From the molecular biophysical point of view such measurements are performed for characterization of structural and conformational transitions caused by physical and electrochemical influences, such as heat, light, electrical fields, solvents, ions, and other ligands. In all cases, one can distinguish between reversible (allosteric and conformational modifications) and irreversible (denaturation, strand break, enzyme reactions) processes. Besides these investigations, biochemical analysis, clinical tests, and electrochemical synthesis are fruitful applications. 

Liu, X.D., Yu, X.W., Zhang, Y, Xue, W.M. et al. 2002. Characterization of structure and diffusion behaviour of Ca-alginate beads prepared with external or internal calcium sources. J. Microencapsul. 10 775-782. 

The structures and dynamics of supramolecular assemblies are usually complex and cannot be completely characterized by a single technique. This is particularly true for functional systems, which require a minimum size of a few nanometers and a certain balance between flexibility and rigidity to allow for reproducible changes of their states. The difficulties in characterizing such systems are readily apparent for a natural class of supramolecular systems, namely, membrane proteins that are functional when embedded in a lipid bilayer and tend to be extremely difficult to crystallize. To understand structure-dynamics-function relationships of such systems, many pieces of information on length scales between 1 A and several nanometers and time scales between picoseconds and milliseconds have to be assembled and interpreted. The samples are often macroscopically disordered systems, and the conformation of the molecules is distributed to some extent. Techniques for local characterization of structures and dynamics at selected sites are required to reduce the complexity of the problem. 

Samuels, R. J. Yee, R.Y. (1972). Characterization of structure and organization of beta-form crystals in type-iii and type-iv beta-isotactic polypropylene spherulites. Polym. Sci. PartA-2 Polymer Phys., Vol.lO, Issue 3, pp. 385-432. 

MS is utilized for the characterization of structures and determination of molecular weight. The production of gaseous ions from surfactants is carried out using soft ionization techniques. The chosen technique depends on the surfactant but those frequently used are field desorption and fast atom bombardment... 

Structure and dynamics studies of deuterated peptides and proteins by MAS solid-state NMR have been reviewed by Reif. It has been shown that perdeuteration and back substitution of exchangeable protons in microcrystalline proteins, in combination with recrystallization from D2O-containing buffers, significantly reduce H- H dipolar interactions leading to amide proton line widths on the order of 20 Hz. Aliphatic protons are accessible either via specifically protonated precursors or by using low amounts of H2O in the bacterial growth medium. As emphasised in this article, the labelling scheme enables characterization of structure and dynamics in the solid-state without dipolar truncation artifacts. 

Huang, H.-H., Glaser, R.H., and Wilkes, G.L. (1987) Structure-property behavior of new hybrid materials incorporating organic oligomeric species into sol—gel glasses. IV. Characterization of structure and extent of reaction. Proc. PMSE ACS Div., 56, 85812. 

Nuclear magnetic resonance (NMR) is the responses of nuclear spins to external radiofrequency (RF) stimulations, or the absorption and reemission of RF pulses by nuclear spins in a magnetic field. NMR techniques are developed to utilize this NMR phenomenon for the characterization of structures and dynamic properties of molecular systems, and for the identification and visualization of molecules and distributions. In the field of PEMFCs, the NMR techniques are frequently applied to the development and improvement of essential materials, proton exchange membrane and electrocatalysts, and the water management of PEMFCs. 

In recent years, it has evidenced a remarkable progress using solid-state MAS NMR to monitor the structure and dynamics, especially hydrogen bonding network and proton dynamics of polymer exchange membrane. Suarez and Greenbaum have reviewed the contribution of NMR spectroscopy to the development of the PEMFC, with particular emphasis on its use in the characterization of structure and transport in polymer electrolyte membranes [3]. Graf reviewed the application of 2D rotor-synchronized... 

Characterization of Structure and Microtexture of Carbon Materials by Magnetoresistance Technique, F. Hishiyama, Y. Kaburagi, and M. Inagaki Electrochemical Carbonization of Fluoropolymers, L. Kavan Oxidation Protection of Carbon Materials, Douglas W. McKee... 

In subsequent research, Sinha Ray et al. [26,27] prepared PLA nanocomposites with organically modified synthetic fluorine mica (OMSFM). For the characterization of structure and morphology of prepared nanocomposites, they first... 

Hatfield G R, Guo Y, Killinger W E, Andrejack R A and Roubicek P M (1993) Characterization of structure and morphology in two poly (ether-6/ocAramide) copolymers. 

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