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排序方式: 共有532条查询结果,搜索用时 81 毫秒
51.
G. A. Emel’chenko A. N. Gruzintsev A. B. Kulakov É. N. Samarov I. A. Karpov A. N. Red’kin E. E. Yakimov C. Barthou 《Semiconductors》2007,41(2):176-179
The spectra of spontaneous and stimulated emission of ZnO nanorods grown by two low-temperature procedures are studied. Stimulated emission at 385 nm is observed at room temperature in CVD ZnO nanocrystals pumped by the nitrogen laser radiation at the wavelength 337 nm. The threshold pumping power density for lasing exitonic recombination is ~600 kW/cm2. 相似文献
52.
53.
Interactions of silicone rubbers designed for electrical engineering applications with aqueous media
L. B. Boinovich A. M. Emel’yanenko A. S. Pashinin 《Protection of Metals and Physical Chemistry of Surfaces》2009,45(1):89-94
Interactions of a number of electrical engineering silicone rubbers with water and aqueous salt, weakly acidic, and weakly basic solutions were studied by measuring contact angles. A mechanism for leakage currents along the surfaces of silicone insulators was proposed. 相似文献
54.
V. S. Gorelik Yu. P. Voinov G. A. Emel’chenko V. M. Masalov N. I. Yurasov V. V. Gryaznov 《Inorganic Materials》2009,45(6):645-650
We analyze broadband visible reflectivity spectra of opal photonic crystals annealed in an argon atmosphere and air. Scanning electron microscopic examination has shown that the crystals consist of close-packed spheres with a mean diameter in the range 200–290 nm. Incorporation of even small amounts of carbon (?0.5 wt %) increases the density of the opal matrix. The presence of carbon shifts the Bragg reflection peak of the opal and increases its intensity. 相似文献
55.
Emel Karacay 《International Journal of Food Properties》2013,16(5):960-971
Oranges were sanitized, dried, peeled and segmented. Undamaged segments were packed under passive and active MAP with low and high oxygen in PP trays sealed with CPP/OPP film. Overall quality of the segments were monitored for 25 days at 4°C. The results showed that orange segments could be stored under passive and active MAP without significant microbial growth. There were slight changes in acidity and Brix (p ≤ 0.05) with no significant changes in pH and sugar. The hardness increased and color (L, a, b) decreased during storage. Orange segments remained in a commercially viable condition for 10 days under MAP. 相似文献
56.
The problem of semantic clustering of subject-oriented natural language texts is discussed. Based on the theory of Formal Concept Analysis, an approach is proposed to determine the measure of semantic affinity of texts. 相似文献
57.
The results are given of observation of a fundamentally novel phenomenon, namely, the formation of detonation wave of condensation.
Experiments are performed behind shock waves in mixture containing 10–30% carbon suboxide C3O2 in argon. The release of the energy of condensation of highly supersaturated carbon vapor formed upon instantaneous thermal
decomposition of carbon suboxide C3O2 → C + 2CO behind the wave front leads to the amplification of shock wave and its transition to the detonation mode. 相似文献
58.
Capacitance-voltage characteristics of tunneling diodes fabricated by co-implantation of erbium and oxygen in single-crystal (111)Si wafers have been studied. Anomalous enhancement of the p-n-junction capacitance with increasing reverse bias has been observed at certain temperatures depending on the implantation dose. The rise in capacitance (decrease in the space charge region width) is associated with the formation of deep levels of high density in the band gap of n-layer of the p-n junction and electron emission from these levels in the space charge region with increasing voltage. The obtained results show that the parameters of the defects responsible for the levels depend on the erbium and oxygen implantation doses. 相似文献
59.
An Industrial Competitiveness Model 总被引:4,自引:0,他引:4
Muhittin Oral 《IIE Transactions》1986,18(2):148-157
The essence of strategic management is to generate within the firm the capability and the potentiality and then fully utilize them to better cope with competition. For this, however, the “competitiveness” level of a firm needs to be defined and measured. The present paper proposes a model for (i) measuring the competitiveness level of a given industrial firm, (ii) identifying the strengths and weaknesses of the firm, and (iii) formulating strategies to improve the competitive position of the firm. Field experience with this model is encouraging enough to discuss its usefulness as a tool for competitive strategy formulation. 相似文献
60.
O. A. Emel’yanov 《Technical Physics Letters》2001,27(8):679-682
A stationary temperature state of a polar polymer dielectric exposed to an electric field is studied. A special feature of
the dielectrics of this type is the presence of a maximum in the loss factor ε″(T) above the glass transition temperature. Using an approach based on the Kirkwood formula for ε″(T), exact solutions to a nonlinear model problem are obtained. These solutions show the multiplicity of the stationary temperature
states and the surface of these states in the “load-ambient temperature” space of parameters exhibits a topological singularity
of the “fold” type. 相似文献