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991.
《Mathematische Nachrichten》2018,291(8-9):1177-1190
We introduce homogeneous Besov and Triebel–Lizorkin spaces with variable indexes. We show that their study reduces to the study of inhomogeneous variable exponent spaces and homogeneous constant exponent spaces. Corollaries include trace space characterizations and Sobolev embeddings. 相似文献
992.
Ghasem Rashidian Sara Bahrami Gorji Mehdi Naderi Farsani Marko D. Prokić 《Natural product research》2020,34(17):2413-2423
AbstractMedicinal plants play an important role in aquaculture as feed additives. This study aimed to investigate effects of alcoholic extract of acorn on growth performance, body composition, digestive enzymes activity and blood biochemical parameters of rainbow trout (O. mykiss) as a commercially important fish. Five dietary treatments were supplemented: 100, 200, 400 and 600?mg.kg?1 of the extract. Fishes were fed twice per day for 8?weeks, and results showed that acorn extract positively affected all investigated parameters in rainbow trout fishes. Digestive enzymes activity and growth performance were increased, while activity of liver enzymes and cortisol were lowed in comparison to control individuals. Body composition of treated animals was also enhanced. Comparison between treated groups together with integrative biomarker response (IBR) values indicated greatest effects in animals fed with 400 and 600?mg.kg?1 of the extract. Positive effects of the acorn represent promising start point for further studies. 相似文献
993.
Oxana V. Kharissova Evgeny M. Kopnin Victor V. Maltsev Nikolai I. Leonyuk Luis Manuel León-Rossano Ilya Yu. Pinus 《固体与材料科学评论》2014,39(4):253-276
This article is focused on principal Bi-containing superconductors. Recent results obtained on Bi-2212, Bi-2223, and related composite materials are discussed. Special attention is paid to various advanced methods of synthesis. Optimization of the superconducting properties by the chemical modifications is considered in terms of most important practical applications. 相似文献
994.
Good quality single crystals of 2-aminophenol were grown by slow evaporation solution growth technique at room temperature. Crystal structure and crystalline nature was determined by X-ray diffraction studies. Prescence of functional groups in the crystal was confirmed by FT-IR analysis. UV transmittance study shows the large transmittance in the entire visible region. Dielectric constant and loss for the crystals were taken at different tempeature. Photoconductivity study exhibits positive nature of the grown crytal. DC conductivity studies were also carried out for the grown crystal. 相似文献
995.
Song-Tao Dong Bin-Bin Zhang Lunyong Zhang Y.B. Chen Jian Zhou Shan-Tao Zhang Zheng-Bin Gu S.H. Yao Yan-Feng Chen 《Physics letters. A》2014
A series of Gd-doped Sr2IrO4 single crystals were grown using a flux method. Analysis of the temperature-dependent resistance of these crystals reveals that these samples show two-dimensional weak localization at 150 to 300 K, while three-dimensional variable range hopping (VRH) behavior is observed at temperatures lower than 150 K. Two localization lengths are observed in the VRH behavior, with a transition temperature of around 88 K. Correspondingly, temperature-dependent magnetization observations along the ab-plane reveal magnetic anomalies at both 150 and 85 K. This work demonstrates the correlation between the electrical and magnetic properties of 5d transition-metal compounds. 相似文献
996.
997.
采用直流双靶磁控溅射聚焦共沉积技术在Fe衬底上高速率生长A lN薄膜,结果表明,双靶共沉积技术有效地提高了A lN薄膜生长速率,相同工作气压或低N2浓度时双靶磁控溅射沉积速率约为单靶沉积速率的2倍;随着溅射系统内工作气压或N2浓度的升高,薄膜生长速率不断减小;薄膜择优取向与薄膜生长速率相互影响,随着工作气压的升高,(100)晶面的择优生长减缓了薄膜生长速率的降低,随着N2浓度的升高,(002)晶面的择优生长加剧了薄膜生长速率的降低,而相对较低的溅射沉积速率有利于(002)晶面择优取向生长。 相似文献
998.
Numerous studies including continuous Czochralski method and double crucible technique have been reported on the control of macroscopic axial resistivity distribution in bulk crystal growth. The simple codoping method for improving the productivity of silicon single-crystal growth by controlling axial specific resistivity distribution was proposed by Wang [Jpn. J. Appl. Phys. 43 (2004) 4079]. Wang [J. Crystal Growth 275 (2005) e73] demonstrated using numerical analysis and by experimental results that the axial specific resistivity distribution can be modified in melt growth of silicon crystals and relatively uniform profile is possible by B–P codoping method. In this work, the basic characteristic of 8 in silicon single crystal grown using codoping method is studied and whether proposed method has advantage for the silicon crystal growth is discussed. 相似文献
999.
本文使用铱坩埚感应加热Czochralski法成功地生长出了无色透明且尺寸达5 0mm× 6 0mm的Lu2 SiO5:Ce晶体。XRD结构分析表明 ,该晶体为单斜结构。在室温下分别以X射线和紫外光为激发源测量了该晶体的发射光谱 ,获得的发射波长分别为 4 0 3nm和 4 2 0nm ,光衰减时间为 4 1ns,光产额达 32 0 0 0p/MeV。发射光谱的双峰结构以及晶体的发光特性证明其发光源于Ce3 离子的 5d1→5F5/ 2 和 5d1→5F7/ 2 跃迁。 相似文献
1000.
Strong and stable red photoluminescence from porous silicon prepared by Fe-contaminated silicon 总被引:1,自引:0,他引:1
D. Y. Lee J. W. Park J. Y. Leem J. S. Kim S. K. Kang J. S. Son H. B. Kang Y. H. Mun D. K. Lee D. H. Kim I. H. Bae 《Journal of Crystal Growth》2004,260(3-4):394-399
Strong red photoluminescence (PL) spectra appeared at porous silicon (PS) samples prepared by a chemical anodization of Fe-contaminated Si substrates. The Fe1000 sample with Fe contamination of 1000 ppb showed a ten times stronger red PL than that of the reference PS sample without any Fe contamination, and this sample also showed the higher thermal stability for PL spectra as compared with the reference PS sample. Furthermore, the PL intensity from the PS with Fe contamination is linearly proportional to the Fe-related trap concentrations of Si substrates obtained from DLTS. Especially, all the PS samples exhibit the same PL peak position regardless of Fe contamination concentrations, as compared with that of the reference PS. This means that there is no significant effect such as the variation of size distribution of nanocrystalline Si in PS layer formed on Fe-contaminated Si substrate. Based on the results of PL and DLTS, we found that the PL efficiency depends strongly on the Fe-related trap concentration in Si substrates. 相似文献