Composite growth surface

Fio. 7. Schematic of the composite growth surface showing the sequence of layers involved in the reaction process. From Nagelberg [29],... 

Fluoroelastomers Novikova et al. [32] reported unproved physico-mechanical properties of fluoro mbbers by reinforcement with chopped polyamide fibers. Other fiber reinforcements are covered by Grinblat et al. [33]. Watson and Francis [34] described the use of aramid (Kevlar) as short fiber reinforcement for vulcanized fluoroelastomer along with polychloroprene mbber and a co-polyester TPE in terms of improvement in the wear properties of the composites. Rubber diaphragms, made up of fluorosilicone mbbers, can be reinforced using aramid fiber in order to impart better mechanical properties to the composite, though surface modification of the fiber is needed to improve the adhesion between fluorosUicone mbber and the fiber [35]. Bhattacharya et al. [36] studied the crack growth resistance of fluoroelastomer vulcanizates filled with Kevlar fiber. 

The electrochemical behavior of single-crystal (100) lead telluride, PbTe, has been studied in acetate buffer pH 4.9 or HCIO4 (pH 1.1) and KOH (pH 12.9) solutions by potentiodynamic techniques with an RRDE setup and compared to the properties of pure Pb and Te [203]. Preferential oxidation, reduction, growth, and dissolution processes were investigated. The composition of surface products was examined by XPS analysis. It was concluded that the use of electrochemical processes on PbTe for forming well-passivating or insulating surface layers is rather limited. 

For crystal growth at constant rate, if the crystal composition can respond to interface melt composition through surface equilibrium, steady state may be reached (Smith et ah, 1956). At steady state, (dCldt) = 0 by definition. Hence,... 

Crystal shape, size, and density all affect the physical properties of the final solid fat matrix. Crystal growth, primary nucleation, and secondary nucleation in fat systems are influenced by many factors, including diffusion, molecular compatibility, TAG structure, nuclei composition and surface properties, number of nuclei, and processing conditions (temperamre and/or shear) (38, 39). It is during the crystallization process of fats that the template for the final physical properties of the material is created. 

The microstructures of ceramic matrices grown from two different classes of alloys have been reported. The external growth surface of ceramic matrices grown from an Al-Si-Mg alloy in the absence of a reinforcement was covered by a thin ( 1- to 4-gm) layer of MgO that sometimes contained up to 5% MgAl204 [33]. The external MgO layer typically was separated from the interconnected A1203 matrix by a thin aluminum alloy (1- to 3-gm) layer. Only rarely was an A1203 grain found in direct contact with the external oxide layer. Within the bulk of the composite, the metallic channels typically were 3 to 8 /tm in width. 

Soils are extremely important environmentally, for they provide the medium and the essential nutrients for plant growth and strongly influence the chemical composition of surface- and groundwaters. Soils are also called upon to remove or attenuate contaminants derived from the atmosphere or released from the surface or near-surface disposal of wastes. We will limit our discussion of soils to a few basic principles. For a more thorough treatment of soil geochemistry the reader is referred to books by Loughnan (1969), Greenland and Hayes (1978), Lindsay (1979), Rose et al. (1979), Bolt (1979), Drever (1985), and Sposito (1989). 

In spite of the role of the dominant deposition precursor in determining the structure and composition of the deposited him, it is also worth examining the possible roles of minority species that are present at low concentrations in the plasma and are not expected to have signihcant quantitative contribution to the hhn growth process. Of particular interest are species that are very reactive with the growth surfaces, such as SiH radicals and small Si H, clusters with n > 1. Indeed, such species may have both benehcial and detrimental effects on the structural quahty of the deposited him. 

Reeder, R. L, Valley, j. W., Graham, C. M. Eiler, 1. M. 1997. Ion microprobe smdy of oxygen isotopic compositions of structurally nonequivalent growth surfaces on synthetic calcite. Geochimica et Cosmochimica Acta, 61, 5057-5063. 

The effect of chemical bath composition, electrodeposition potential, etc., on film composition was determined [317]. The precursor films were loaded in a physical evaporation chamber and additional In or Cu and Se were added to the films to adjust the final composition of CIS. The device fabricated using electrodeposited Cu-In-Se precursor layers had a solar cell efficiency of 9.4%. CIS thin films have also been obtained from different precursors prepared by direct or sequential electrodeposition processes [303]. The results showed that thin crystalline chalcopyrite CIS films with the desired composition can be obtained after annealing, whether directly or sequentially electrodeposited precursors at 400 °C. An improvement in film quality was obtained by using an electrodeposited Cu layer as the growth surface for CIS formation. If elemental Se was also added during the heat treatment, then a higher recrystalHzation of the films was observed. A new approach for CIS formation by sequential electrodeposition of Cu and In-Se layers and subsequent heat treatment with elemental selenium in Ar + H2 flows has been presented [304]. An increase in the film crystallinity was achieved... 

The geometric structure and diemical composition of surfaces and interfaces is of fundamental importance for the initial growth of films... 

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