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61.
ZTE Corporation 《中兴通讯技术(英文版)》2012,10(3):F0002-F0002
22 August 2012-ZTE Corporation, a publicly listed global provider of telecommunications equipment and network solutions, announced its interim results for the six months ended 30 June 2012. Based on both HKFRS and PRC ASBE, ZTE recorded revenue of RMB 42.64 billion for the period, an increase of 15.2% year-on-year. Pre-tax profit in the period was RMB 656 million, a decrease of 48.5% year-on-year. 相似文献
62.
ZET Corporation 《中兴通讯技术(英文版)》2011,9(3):F0003-F0003
At the BASE media meeting held in Berlin, ZTE met with senior executives from the E-Plus Group on September 9, 2011 to discuss expansion of its mobile device portfolio in Germany. E-Plus, one of the largest mobile operators in Germany, has been 相似文献
63.
Richard Whitehead 《通讯世界》2011,(5):40-40
戴玫瑰色眼镜不是我的风格,我倾向以冷酷严厉的目光审视事物。数周前,Amazon Web Services崩溃,致使数千企业疑虑,是否还能看到他们的网站起死回生再次可用。很显然,AWS并没有充分的ec2备份计划,令许多过分乐观的IT安全人员以及他们的客户深受震惊。 相似文献
64.
Yiwei Zhang Yuming Zhou Lihui Wan Mengwei Xue Yongzheng Duan Xuan Liu .School of Chemistry Chemical Engineering Southeast University Nanjing Jiangsu China .Biochemical Environmental Engineering College Nanjing Xiaozhuang University Nanjing 《天然气化学杂志》2011,20(6):639-646
Catalytic dehydrogenation of isobutane has recently received considerable attention because of the increasing demand for isobutene.In this study,the synergistic effect between Sn and K on PtSnK/γ-Al2O3 catalysts has been investigated by changing the content of Sn.It was found that with the presence of potassium,suitable addition of Sn could not only increase the metal dispersion,but also reduce the catalyst acidity.In these cases,the synergistic effect could also strengthen the interactions between the metal and support,which resulted in an increase in both catalytic activity and stability.In our experiments,Pt-0.6SnK/Al catalyst exhibited the lowest deactivation rate (12.4%) and showed a selectivity to isobutene higher than 94% at the isobutane conversion of about 45.3% after running the reaction for 6 h.However,with the excessive loading of Sn,surface property of active sites and the interactions between metal and support were changed.As a result,the initial optimal ratio between the metallic function and acid function would be destroyed,which was disadvantageous to the reaction. 相似文献
65.
光谱痕量分析的检出限问题 总被引:2,自引:0,他引:2
陈远盘 《光谱学与光谱分析》1994,14(5):105-110
本文研究了光谱分析中的检出限问题。对目前文献中提出的一些检出限的公式进行了归纳和推导。讨论了IUPAC和Long检出限公式的一些实际应用。 相似文献
66.
介绍一种纠误码光纤通信系统原理框图,讨论了交错延迟十单位正反码自动纠误编码体制,指出这种纠误码光纤通信系统不但允许信息短期中断,而且可延长通信系统中继距离。作者已研制出低速交错延迟自动纠误设备,其编码与5B6B码型相比,可使系统可靠性显著提高,并减少字同步建立时间。 相似文献
67.
文章介绍了近年来光纤活动连接器,光分、合波器,光开关等光通信无源器件的现状及发展趋势,尤其介绍了光纤用户网系统光纤无源器件的开发情况。 相似文献
68.
69.
The analytical expressions of the various structural units and the average degree of branching for the hyperbranched polymers resulted from AB_2 polycondensation with substitution effect were derived by the kinetic mechanism.The reactivity difference between the B group in linear unit and that in terminal group has great effect on the molecular parameters of the products obtained.The concentration of terminal units has a maximum with the increase of the conversion of A groups(x).The higher the reactivity... 相似文献
70.
ZHANG Xia LIU Wei XU Yong YANG Liu KONG Wei-song RUI Xiao-dong YANG Shuai CHEN Yong-kuan MIAO Ming-ming .Key Laboratory of Tobacco Chemistry Yunnan Academy of Tobacco Science Kunming P.R.China .Research Development Center of Hongta Tobacco Corporation Limited Yuxi 《高等学校化学研究》2011,(4):550-556
The comparison of solid phase extraction(SPE) for the preconcentration and isolation of polyphenols in tobacco samples was carried out by ultra-high performance liquid chromatography/tandem mass spectrometry (UPLC/MS/MS) and multivariate analysis.Several adsorbing materials of SPE(C18,NH2,SAX and OASIS) were investigated.It was found that the C18 and OASIS cartridges can not only speed up the purification process,but also simplify the SPE operation.A UPLC/MS/MS was used for the determination of polyphenols ... 相似文献