A structure and composition

Marita, J. M. Ralph, J. Hatheld, R. D. Guo, D. Chen, F. Dixon, R. A. Structural and compositional modihcations in lignin of transgenic alfalfa down-regulated in caffeic acid 3-O-methyltransferase and caffeoyl coenzyme A 3-O-methyltransferase. 

Mann, S. Bannister, J.V. Williams, R.J.P. (1986 a) Structure and composition of ferritin cores isolated from human spleen, limpet (patella vulgata) hemolymph and bacterial (Pseudomonas aeruginosa) cells. J. Mol. Biol. 188 225-232... 

For example, Fig. la shows a high-resolution TEM image of a complex catalyst, Pt/CeTbO c, a metal supported on a mixed-metal oxide with a structure and composition the determination of which require elaborate image contrast simulations using various model structures 10). Furthermore, the platinum particles are partly embedded in the oxide support, creating sites with activities... 

The first reaction involves a structural and compositional change in the active mass (near the surface), while the second reaction involves only the dehthiation (and Li2C03 formation). It should be noted that Li2C03 films formed on Li MOj, inhibit the kinetics of Li insertion and should be considered as a detrimental phenomenon. 

Careful sample preparation is critical for obtaining useftil structural information from surface-sensitive techniques such as XPS. We have found that fracturing the glass sample in vacuum immediately before analysis produces a surface with a structure and composition that is most representative of the bulk. For reasons aheady outlined, polished samples or samples exposed to the ambient have compositionally and structurally altered surfaces that yield misleading results. Surfaces that are created by inert ion sputtering in vacuum also are altered relative to the bulk. 

Watson, S. A. Structure and composition. In Corn Chemistry and Technology Watson, S. A., Ransted, P. E., Editors American Association of Cereal Chemists Minneapolis, MN, 1987 pp. 53-82. 

Homogeneity of data. Homogeneous data will be uniform in structure and composition, usually possible to describe with a fixed number of parameters. Homogeneous data is encountered in simple NDT inspection, e.g. quality control in production. Inhomogeneous data will contain various combinations of indications from construction elements, defects and noise sources. An example of inhomogenous data are ultrasonic B-scan images as described in [Hopgood, 1993] or as encountered in the ultrasonic rail-inspection system described later in this paper. 

Salaita G N, Lu F, Laguren-Davidson L and Flubbard A T 1987 Structure and composition of the Ag(111) surface as a function of electrode potential in aqueous halide solutions J. Electroanal. Chem. 229 1-17... 

The major STEM analysis modes are the imaging, diffraction, and microanalysis modes described above. Indeed, this instrument may be considered a miniature analytical chemistry laboratory inside an electron microscope. Specimens of unknown crystal structure and composition usually require a combination of two or more analysis modes for complete identification. 

It is known that thin (-20 A) passive films form on iron, nickel, chromium, and other metals. In s ressive environments, these films provide excellent corrosion protection to the underlying metal. The structure and composition of passive films on iron have been investigated through iron K-edge EXAFS obtained under a variety of conditions, yet there is still some controversy about the exact nature of... 

Photoluminescence is a well-established and widely practiced tool for materials analysis. In the context of surface and microanalysis, PL is applied mostly qualitatively or semiquantitatively to exploit the correlation between the structure and composition of a material system and its electronic states and their lifetimes, and to identify the presence and type of trace chemicals, impurities, and defects. 

The structure and composition of the lithium surface layers in carbonate-based electrolytes have been studied extensively by many investigators [19-37], High reactivity of propylene carbonate (PC) to the bare lithium metal is expected, since its reduction on an ideal polarizable electrode takes place at much more positive potentials compared with THF and 2Me-THF [18]. Thevenin and Muller [29] found that the surface layer in LiC104/PC electrolyte is a mixture of solid Li2C03 and a... 

The above results correlate well with studies by Ratner et al. [979,980] who used samples of defined particle size and surface area. They report the rapid formation at 503—523 K of nuclei of a new phase on NH4Re04 surfaces and that decomposition is accompanied by a surface area increase. There is a marked reduction in conductivity (X 10"8) near the onset of reaction. Structures and compositions of the product phases are discussed. 

Smith and Stirton applied this mechanism to the sulfonation of long-chain fatty acid esters [31]. Instead of forming the well-defined mixed anhydride during the reaction of fatty acids with S03, the acid esters form a complex less defined in structure and composition. In this complex the a-hydrogen is activated, so that a second molecule of S03 can react. These two addition steps are fast. The final step is again a slow rearrangement of the intermediate with a loss of one molecule of S03. 

A new form of carbon coating is now available which is neither diamond nor graphite and is known as diamond-like carbon (DLC).bl DLC can be considered as a metastable carbon produced as a thin coating with a broad range of structure and composition.l b[42]... 

Such studies have shown that it is the chemical structure and composition that determine whether or not synthetic polymers are biodegradable. On the other hand, the precise rate at which a synthetic polymer will degrade is determined by the specific morphology of the article into which the polymer has been fabricated. 

This study is the first report of the presence of rhamnogalacturonan n in fruit-derived products with the exception of the RG-n from wine [20]. Our RG-II preparations correspond very closely to the described model [1,13], confirming the conservation of its structure among plant cell walls. The complexity of the structure and composition of RG-II with several rare sugars uneasy to identify may be one possible explanation of why this fascinating molecule remained undetected in apple juices for such a long time. 

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