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Composites performance structural

Expertise in the manufacture of composite and structured materials from large molecules Expertise in the manufacture of high-performance and specialty materials... [Pg.26]

The role of the distribution of species in solution in determining the CdS film composition and structure was studied by Rieke and Bentjen [244], who performed equilibrium analysis of the cadmium-amine-hydroxide system to predict the spe-ciation in solution. The focus was on the formation of Cd(OH)2 and Cd(NH3) species due to their importance in film growfh. If was concluded fhat for deposition of high-quality, adherent, phase-pure CdS films, a surface cafalytically active toward thiourea decomposition is desirable. The Cd(OH)2 film was thought to be responsible for this effect. [Pg.134]

A highly detailed picture of a reaction mechanism evolves in-situ studies. It is now known that the adsorption of molecules from the gas phase can seriously influence the reactivity of adsorbed species at oxide surfaces[24]. In-situ observation of adsorbed molecules on metal-oxide surfaces is a crucial issue in molecular-scale understanding of catalysis. The transport of adsorbed species often controls the rate of surface reactions. In practice the inherent compositional and structural inhomogeneity of oxide surfaces makes the problem of identifying the essential issues for their catalytic performance extremely difficult. In order to reduce the level of complexity, a common approach is to study model catalysts such as single crystal oxide surfaces and epitaxial oxide flat surfaces. [Pg.26]

Successful combination of a chromatographic procedure for separating and isolating additive components with an on-line method for obtaining the IR spectrum enables detailed compositional and structural information to be obtained in a relatively short time frame, as shown in the case of additives in PP [501], and of a plasticiser (DEHP) and an aromatic phenyl phosphate flame retardant in a PVC fabric [502], RPLC-TSP-FTIR with diffuse reflectance detection has been used for dye analysis [512], The HPLC-separated components were deposited as a series of concentrated spots on a moving tape. HPLC-TSP-FTIR has analysed polystyrene samples [513,514], The LC Transform has also been employed for the identification of a stain in carpet yarn [515] and a contaminant in a multiwire cable [516], HPLC-FTIR can be used to maintain consistency of raw materials or to characterise a performance difference. [Pg.496]

Analytical investigations usually concern samples which are temporally and locally invariant. This kind of analysis is denoted as bulk analysis (average analysis). On the other hand, analytical investigations can particularly be directed to characterize temporal or local dependences of the composition or structure of samples. One has to perform dynamic analysis or process analysis on the one hand and distribution analysis, local analysis, micro analysis, and nano analysis on the other. [Pg.34]

Detailed studies on the lipase-catalyzed polymerization of divinyl adipate and 1,4-butanediol were performed [41-44]. Bulk polymerization increased the reaction rate and molecular weight of the polymer however, the hydrolysis of the terminal vinyl ester significantly limited the formation of the polyester with high molecular weight. A mathematical model describing the kinetics of this polymerization was proposed, which effectively predicts the composition (terminal structure) of the polyester. [Pg.245]

Although the electrode performance can be improved by the introduction of compositional and microstructural gradients into the anode or cathode, the processing required to produce such graded layers also increases in complexity as the number of discrete layers increases, particularly when separate deposition and firing steps are required for each increment in layer composition or structure. [Pg.250]

Although silicone oils by themselves or hydrophobic particles (e.g., specially treated silica) are effective antifoams, combinations of silicone oils with hydrophobic silica particles are most effective and commonly used. The mechanism of film destruction has been studied with the use of surface and interfacial tensions, measurements, contact angles, oil-spreading rates, and globule-entering characteristics for PDMS-based antifoams in a variety of surfactant solutions.490 A very recent study of the effect of surfactant composition and structure on foam-control performance has been reported.380 The science and technology of silicone antifoams have recently been reviewed.491... [Pg.679]

In summary, modeling offers powerful tools and guidance for performance optimization. With advancements in new techniques for micro- and nanofabrication, it will be possible to engineer fuel cell CLs (electrodes) according to the compositions and structures predicted by modeling and simulation. [Pg.93]

BMI polymers have glass transition temperatures in excess of 260°C and continuous-use temperatures of 200-230°C. BMI polymers lend themselves to processing by the same techniques used for epoxy polymers. They are finding applications in high-performance structural composites and adhesives (e.g., for aircraft, aerospace, and defense applications) used at tem-peratrues beyond the 150-180°C range for the epoxies. Bisnadimide (BNI) polymers are similar materials based on bisnadimides instead of bismaleimides. [Pg.155]

Emulsification is a stabilizing effect of proteins a lowering of the interfacial tension between immiscible components that allow the formation of a protective layer around oil droplets. The inherent properties of proteins or their molecular conformation, denaturation, aggregation, pH solubility, and susceptibility to divalent cations affect their performance in model and commercial emulsion systems. Emulsion capacity profiles of proteins closely resemble protein solubility curves and thus the factors that influence solubility properties (protein composition and structure, methods and conditions of extraction, processing, and storage) or treatments used to modify protein character also influence emulsifying properties. [Pg.340]

The increasing use of high-performance fibrous composites in critical structural applications has led to a need to predict the lifetimes of these materials in service environments. To predict the durability of a composite in service environment requires a basic understanding of (1) the microscopic deformation and failure processes of the composite (2) the significance of the fiber, epoxy matrix and fiber-matrix interfacial region in composite performance and (3) the relations between the structure, deformation and failure processes and mechanical response of the fiber, epoxy matrix and their interface and how such relations are modified by environmental factors. [Pg.3]

Inorganic Reinforcements for High-Performance Structural Composites... [Pg.492]


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See also in sourсe #XX -- [ Pg.482 ]




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