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991.
通过一个工程实例,说明了提高室内设计相对湿度未必能降低空调系统能耗,指出了选择合理的室内设计相对湿度要综合考虑包括能耗在内的各方面因素. 相似文献
992.
Wei Lu Ping Zheng Wenjuan Du Zhongyan Meng 《Journal of Materials Science: Materials in Electronics》2004,15(11):739-742
Lanthanum nickel oxide (LaNiO3 or LNO) conducting thin films that could be used as electrodes for improving fatigue and aging properties of ferroelectric thin films were investigated. In this paper, LNO films were directly spin-coated onto SiO2/Si(1 0 0) substrates followed by thermal treatment in air and in oxygen. It was found that crack-free dense and uniform films with good crystallinity and medium grains were obtained, preferentially (1 0 0)-oriented LNO thin films could be formed at a lower annealing temperature of 550 °C and that with the increase in thermal annealing temperature the LNO thin film possessed better electrical properties especially at 750 °C. However, the LNO film displayed a structure transformation above 850 °C. A phenomenon was found that the first heat-treatment temperature and time played a key role to determine the crystallite size of LNO films. A subsequent deposition of a sol–gel derived Pb(Zr0.53Ti0.47)O3 (PZT53/47) thin film on the LNO-coated SiO2/Si(1 0 0) substrates was also found to have a (1 0 0)-oriented texture. Moreover, the Au/PZT/LNO capacitor was found to significantly improve the fatigue and the effects of the LNO electrodes to the fatigue were discussed. 相似文献
993.
S.H. Hu J. Chen Z.G. Hu G.S. Wang X.J. Meng J.H. Chu N. Dai 《Materials Research Bulletin》2004,39(9):1223-1229
Bi3.25La0.75Ti3O12(BiLT) thin films with different thickness were successfully deposited onto fused quartz by chemical solution deposition. X-ray diffraction analysis shows that BiLT thin films are polycrystalline with (0 0 2)-preferred orientation. The dispersion of refractive indices of the BiLT thin films was investigated by the optical transmittance spectrum. The optical band gap energy was estimated from the graph of (hνα)2 versus hν. The results show that the refractive index and band-gap energy of the BiLT thin films decrease with the films thickness. 相似文献
994.
Structural-mechanical relationship of epoxy compatibilized polyamide 6/polycarbonate blends 总被引:1,自引:0,他引:1
Polyamide 6 (PA6)/polycarbonate (PC) blends compatibilized with solid epoxy resin (bisphenol type-A) were prepared by extrusion followed by injection molding. The effects of epoxy resin on the microstructure, tensile, impact and compatibility of the PA6/PC blends were investigated. The results showed that both the tensile modulus and elongation at break of PA6/PC blends were inferior as compared to their parent polymers. This resulted from incompatibility between the PA6 and PC phases. SEM observation revealed that the introduction of 0.5 part per hundred (phr) epoxy resin into the PA6/PC75/25 blend yields a finer dispersion of PC phase in PA6 matrix. The boundaries between the PC domains and PA6 matrix became obscure with the incorporation of 1 phr epoxy resin. Such an improvement in compatibility was suggested to be resulted from the formation of in situ epoxy bridged PA6-PC block copolymer in the blend during compounding. Consequently, the tensile modulus, yield strength and impact strength of the PA6/PC 75/25 blend improved considerably with increasing epoxy content. 相似文献
995.
996.
997.
深入分析了山西省电力公司办公自动化系统的技术构架,针对存在的问题和广域网上办公的要求,提出了基于广域网的办公自动化建设方案。 相似文献
998.
MENG Fanbin LI Yangxian LIU Heyan QU Jingping LIU Zhuhong CHEN Jinglian & WU Guangheng .School of Mechanical Science Engineering Hebei University of Technology Tianjin China .State Key Laboratory for Magnetism Institute of Physics Chinese Academy of Sciences Beijing China 《中国科学E辑(英文版)》2004,47(6)
~~Influence of stresses on martensitic transformation in ferromagnetic shape memory Ni_(50)Mn_(19)Fe_6Ga_(25) ribbons1. Ullakko, K., Huang, J. K., O'Handley, R. C. et al., Large magnetic-field-induced strains in Ni2MnGa single crystals, Appl. Phys. Lett., 1996, 69(13): 1966-1968.
2. James, R. D., Wuttig, M., Magnetostriciton of martensite, Philos. Mag., 1998, A 77: 1273-1275.
3. Wu, G. H., Yu, C. H., Meng, L. Q. et al., Giant magnetic-field-induced strains in H… 相似文献
999.
Daughter minerals in fluid inclusions of garnet and diopside from Tongguanshan Copper Deposit by SEM/EDS and LRM 总被引:2,自引:0,他引:2
YulingXie JiuhuaXu ZengqianHou ZhusenYang WenyiXu YifengMeng BaohuaWang 《北京科技大学学报(英文版)》2004,11(6):481-485
Tongguanshan copper deposit of Tongling large ore belt is one of the typical skarn copper deposits. Based on careful observation under microscope many daughter minerals including transparent ones and opaque ones have been distinguished in the fluid inclusions of garnet and diopside. The results of SEM/EDS (scanning electron microscope/energy dispersive spectrometer) and LRM (laser Raman microprobe) analysis show that these daughter minerals in garnet are sylvite, halite, sphalerite, chalcopyrite and carbonate. Sylvite daughter mineral is very popular in garnet and diopside. The existence of so much sylvite daughter mineral and other daughter minerals in the fluid inclusions indicates that the ore-forming fluid is of supper-high salinity and high potassium concentration. High potassium concentration in the fluid inclusions agrees with K-rich mesotype-acid rock and K-silicate alteration that occurred widely in this area. The daughter mineral assemblage in garnet and diopside is similar to the mineral assemblage of oreforming stage that followed skarn stage. 相似文献
1000.
聚丙烯热失重特性的研究 总被引:2,自引:0,他引:2
采用TG-DTA法研究了聚丙烯在不同气氛下的热失重特性,求取了反应动力学参数,探讨了聚丙烯热失重反应的机理.结果表明,氧气对聚丙烯的失重有明显的促进作用,聚丙烯的热失重反应均符合一级反应模型. 相似文献