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51.
The construction of a diamond-like tetracoordinated quasicrystal (possible only in the infinite point group R) is considered in the framework of algebraic geometry. The physical and materials research applications of this approach are discussed.  相似文献   
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A new genetic algorithm-based approach to the problem of reducing the diagnostic information acquired by testing discrete devices was proposed. Consideration was given to minimization and optimization of the diagnostic information for which the corresponding fitness functions and chromosome structures used in the genetic algorithms were suggested. Statistical data corroborating efficiency of the developed genetic algorithms for the problems under consideration were presented.  相似文献   
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A high-resolution electron backscatter diffraction technique was employed to investigate microstructure evolution during warm working of Ti–6Al–4V with a colony-α microstructure. Particular emphasis was paid to the specific mechanisms governing this process. Microstructure development was found to be driven mainly by the geometrical requirements of the imposed strain and by the kinking of α lamellae. For the most part, the lamellar microstructure was surprisingly stable during straining, with limited globularization observed only in kinked α colonies. The kinking process was shown to be closely linked with the development of shear bands within the colonies. These observations suggest that changes in strain path may be beneficial in promoting globularization during warm working.  相似文献   
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The antimicrobial effect of spice‐based marinades against Campylobacter jejuni on inoculated fresh broiler wings was investigated. Experiments were carried out with 1 strain of C. jejuni and 6 marinades. Four experimental marinades were composed for the study and contained spices (thyme, rosemary, basil, marjoram, and so on) and different combination of bioactive compounds. Two marinades were commercial and contained spices (black pepper, sweet red pepper, and so on) and chemical additives (monosodium glutamate, sodium diacetate, calcium lactate), 1 commercial marinade was also enriched with bioactive compounds (linalool, cinnamaldehyde, lactic acid). Total aerobic bacterial count was examined to estimate the possible effect of tested marinades on the shelf‐life of marinated broiler wings. Study revealed that thyme‐based marinade was the most effective against C. jejuni on broiler wings and reduced the numbers of campylobacters by 1.04 log colony forming unit (CFU)/g (P ≤ 0.05) during storage for 168 h at 4 °C temperature. Moreover, it was more effective against C. jejuni than commercial marinade with 0.47 log CFU/g (P ≤ 0.05) reduction effect. Both experimental and commercial marinades had very similar effect on the total aerobic bacterial count. Although experimental and commercial marinades had different effect on pH of broiler wings, this parameter did not show a major impact on the antimicrobial effect of tested marinades (P ≥ 0.05). Our study shows that experimental natural thyme‐based marinade can reduce numbers of C. jejuni more effectively than tested commercial marinades.  相似文献   
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Solid catalysts for wet oxidation of nitrogen-containing organic compounds   总被引:2,自引:0,他引:2  
Several solid catalysts (Co3O4/γ-Al2O3, Fe2O3/γ-Al2O3, Mn2O3/γ-Al2O3, Zn–Fe–Mn–Al–O, Pt/γ-Al2O3, Ru/CeO2, Ru/C) have been prepared and used to remove N-containing organic contaminants while processing toxic and hazardous industrial waste waters using wet oxidation by air (WAO). The autoclave tests of catalysts were done to reveal the main advantages of catalysts in water presence at high pressures and temperatures. Catalyst activity was determined with regard to oxygen interaction with model mixtures (water–organic contaminant: acetonitrile, carbamide, dimethyl formamide, or multi-component mixture of aliphatic alcohols). Activity tests were done in a static reactor under ideal mixing regime. Reagents and products were monitored using gas chromatograph Cvet-560, Millichrom-1 HPLC, and routine chemical analysis. Optimum process conditions for the best catalyst (Ru/graphite-like carbon) are as follows: partial oxygen pressure – 1.0 MPa, temperature – 473–513 K. At 0.5–5.0 MPa total pressure and 433–523 K catalysts show high water-resistance and high activity level (residual content of toxic compounds is less than 1%, and no NOx and NH3 are detected). There are no legal restrictions on catalysts operation, since they are harmless to environment.  相似文献   
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This paper reports on the results of investigations into the design of an operating prototype of the power plant for the production and accumulation of hydrogen. The objective of this work is to develop technologies of intermediate storage of hydrogen with subsequent generation of an electric power due to the electrochemical processes occurring in fuel cells with an efficiency of no lower than 90%. The power plant is based on the wind power plant, which operates using an integrated software-hardware system for control over the power regime of the entire technological process. New membrane and catalytic materials prepared by the solgel method are used as functional components of fuel cells.  相似文献   
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