排序方式: 共有28条查询结果,搜索用时 218 毫秒
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Dejan M. Gvozdić Jovan B. Radunovic J. M. Elazar 《Journal of Infrared, Millimeter and Terahertz Waves》1993,14(7):1485-1493
In this work the conformal mapping is used to determine an analytical expression for the electric field in MSM structures. The expression simplifies the analysis of optically generated carriers transport, i.e. the determination of the response of the MSN photodetectors. It can also be useful in the analysis of MSM electrooptical modulators operation. 相似文献
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Presents a method for coding Ss in repeated measures designs when the data are subjected to a multiple regression analysis. Instead of having to use a multitude of vectors to code Ss, a single vector is used. The method is illustrated for randomized blocks and split plot designs. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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David Ehre Elazar Y. Gutmanas Rachman Chaim 《Journal of the European Ceramic Society》2005,25(16):3579-3585
Densification of pure nanocrystalline MgO powder with 10 nm particle size by hot-pressing was investigated in the temperature range 700–800 °C, applied pressure range 100–200 MPa, and for durations of up to 240 min. It was shown that significant densification under the pressure begins above 440 °C. Densities higher than 99.5% with grain size of 73 nm were achieved at 790 °C and 150 MPa for a 30 min duration. Remarkable densification from 90 to 99.5% was observed by temperature change from 700 to 790 °C, for which the grain size was doubled only. The final grain size decreased with increasing the applied pressure. Higher shrinkage rates and cumulative shrinkages were recorded by the application of pressure at 550 °C rather than from room temperature. The temperature at which the pressure was applied is crucial in determining the maximum shrinkage rate in the nanocrystalline compacts. This effect was related to the morphological changes of the particles caused by plastic deformation at lower temperatures. Analysis of the densification rate and its comparison to the literature data was in agreement with Coble creep, where self-diffusion of Mg2+ cations along the grain boundaries acts as a main densification mechanism. 相似文献
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Aleksandr V. Korchuganov Aleksandr N. Tyumentsev Konstantin P. Zolnikov Igor Yu. Litovchenko Dmitrij S. Kryzhevich Elazar Gutmanas Shouxin Li Zhongguang Wang Sergey G. Psakhie 《材料科学技术学报》2019,35(1):201-206
This paper reports on a molecular dynamics study of structural rearrangements in a copper nanocrystal during nucleation of plastic deformation under uniaxial tension. The study shows that the resulting nucleation of partial dislocations on the free surface and their glide occurs through local fcc→bcc→hcp transformations via consistent atomic displacements. We propose an atomic model for the generation of dislocations and twins based on local reversible fcc→bcc→fcc transformations, with the reverse one proceeding through an alternative system. The model gives an insight into possible causes and mechanisms of the generation of partial dislocations and mechanical twins in two and more adjacent planes of plastically deformed nanocrystals. The obtained data allow a better understanding of how plasticity is generated in nanostructured materials. 相似文献
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Zoran S. Ilić Radmila Trajković Radoš Pavlović Sharon Alkalai‐Tuvia Yaacov Perzelan Elazar Fallik 《International Journal of Food Science & Technology》2012,47(1):83-90
The goal of this study was to develop a technology for prolonged storage of pepper fruit at low temperature, based on physical treatments and packaging materials. Physical and compositional changes of red bell pepper fruit (Capsicum annuum L. cv.’Selika’) were monitored during 21 days of cold storage (at 2 °C) plus 3 days at 20 °C (market simulation). Fruits were treated with tap and hot water and stored without packaging or sealing each fruit in individual shrink packaging (Cryovac®). This research revealed that individual shrink packaging following prestorage with hot water rinse (55 °C for 15 s) over brushes, significantly reduced weight loss, softening, decay incidence and chilling injury, while maintaining a quality. The wrapped fruit ripened normally (carotenoid content increased) during shelf‐life period, when shifted to 20 °C after unwrapping. This study showed that antioxidant levels of pepper fruit may be preserved during storage. 相似文献
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Zipora Tietel Einat Bar Efraim Lewinsohn Ester Feldmesser Elazar Fallik Ron Porat 《Journal of the science of food and agriculture》2010,90(6):995-1007
BACKGROUND: Mandarins suffer from accumulation of off‐flavours after harvest. In this study the sensory quality and aroma profile composition of homogenised segments of untreated (control) and wax‐coated ‘Mor’ mandarins after 7 days at 20 °C or 3 or 6 weeks of cold storage at 5 °C were examined. RESULTS: Fruit taste score decreased during storage and following wax coating, and this was attributed to decreases in sourness and mandarin flavour and accumulation of off‐flavours. Aroma profiling identified 31 volatiles that decreased by at least 50% during storage and after waxing and thus may be involved in the observed flavour loss. In contrast, 13 volatiles, mostly belonging to ethanol fermentation and fatty acid and amino acid catabolism pathways, significantly increased at least twofold and probably contributed to off‐flavour enhancement. CONCLUSION: The results showed that after harvest there was a progressive decrease in sensory quality of ‘Mor’ mandarins. It is proposed that observed decreases in contents of sesqui‐ and monoterpenes and short‐chain oxygenated fatty acids may contribute to the decrease in mandarin flavour, whereas increases in the contents of ethanol fermentation metabolites and derivates of fatty acid and amino acid catabolism are most likely involved in causing the enhanced sensation of off‐flavours. Copyright © 2010 Society of Chemical Industry 相似文献
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