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61.
62.
The reaction of bisgermavinylidene [(Me3SiN?PPh2)2C?Ge→Ge?C(PPh2?NSiMe3)2] ( 1 ) with AdNCO (Ad = Adamantyl) afforded the [2 + 2] cycloadditon product [(Me3SiN?PPh2)2CGeC(O) NAd] ( 2 ). Similar reaction of 1 with Ph3SiOH in tetrahydrofuran (THF) yielded the base‐stabilized germanium(II) triphenylsiloxide [H2C(PPh2?NSiMe3)2Ge(OSiPh3)2] ( 3 ). The results suggested that reactive germavinylidene may exist in solution and is capable of forming addition reaction products. The X‐ray structures of 2 and 3 were determined. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
63.
D. L. Phillips C. Zhao W. M. Kwok Y.L. Li X. Guan D. Wang 《光散射学报》2005,17(3):251-253
pacc:8240,8760E Acombinedexperimentalandtheoretical studyofthephotochemistryofCHBr3inpurewa terandinacetonitrile/watermixedsolventsisre portedthatelucidatesthereactionsandmecha nismsresponsibleforthephotochemicalconver sionofthehalogenatomsinCHBr3intothre… 相似文献
64.
Kwok Wah Hui Bo Yu Wu Kin S. Chiang 《International Journal of Infrared and Millimeter Waves》1997,18(4):875-887
An analysis is given on the finite element method (FEM) for calculating the various parameters of optical modulators and a
computer program is written to solve the finite element equation. Based on this method, a Mach-Zehnder type electro-optic
modulator with coplanar waveguide (CPW) electrode is designed and fabricated. When compared with the Fourier series method,
small differences on the 3-dB bandwidth, characteristic impedance and half-wave voltage, etc. are obtained. 相似文献
65.
The reduction of ReCl4(THF)2 in the presence of excess t-butylisocyanide by sodium amalgam produces pentakis(t-butylisocyanide)chlororhenium(I), which has been converted to the corresponding methyl and ethyl derivatives. The reaction of pentakis(trimethylphosphine)chlororhenium(I) with ButNC gives partially substituted complexes, ReCl(CNBut)2(PMe3)3 and ReCl(CNBut)3(PMe3)2. The structures of both compounds have been determined by X-ray methods. Octahedral ReCl(CNBut)2(PMe3)3 has trans isocyanide groups with one linear [C---N---C = 175(1)°] and one slightly bent [C---N---C = 159(1)°]. The Re---C bond lengths are equal within experimental error [2.004(7), 2.003(7)Å]. In the octahedral ReCl(CNBut)3(PMe3)2, for which the structure is not well defined, due to disorder, the unique isocyanide trans to chlorine is considerably bent at the nitrogen atom [C---
---C = 141(6)°] and appears to show the shortest Re---C bond length, 1.94(5) vs 2.02(5)Å for the other two isocyanides which are mutually trans. Protonation of these two isocyanide complexes with fluoroboric acid gives, respectively, the salts [ReCl(CNBut)CNHBut(PMe3)3]BF4 and [ReCl(CNBut)2CNHBut(PMe3)2]BF4, whose configurations have been determined by NMR spectroscopy. The reduction by sodium amalgam of Cr2(CO2Me)4 in tetrahydrofuran in presence of ButNC gives a high yield of Cr(CNBut)6 while similar reduction of the dimeric tungsten(II) complex of the anion (mhp) of 2-methyl-6- hydroxypyridine gives W(CNBut)6. Interaction of W2(mhp)4 in methanol-ether with ButNC gives a tungsten(I) complex W2(η-mhp)2(ButNC)4, which may be an intermediate in the reductive cleavage reaction. Interaction of cis-PtMe2(PMe3)2 with ButNC leads only to replacement of one PMe3 group to give the complex cis-PtMe2(PMe3)(CNBut). 相似文献
66.
H. Harde H. Burggraf H. W. K. Tom R. K. Jain P. B. Corkum R. S. Taylor Th. Sizer II J. D. Kafka C. Gable G. Mourou D. H. Auston P. R. Smith S. Williamson R. Trebino A. E. Siegman J. Kuhl J. H. Harris S. Sugai A. V. Nurmikko M. G. Li Veerendra K. Mathur Chi H. Lee M. Hasselbach S. C. Hsu H. S. Kwok 《Applied physics. B, Lasers and optics》1982,28(2-3):246-254
67.
This paper presents a systematic study of liquid droplet impact on three polymer surfaces: poly(methyl methacrylate), poly(methyl methacrylate/n-butyl methacrylate), and poly(n-butyl methacrylate). Changing from one surface to the next represents an incremental variation in solid surface tensions of 5-6 mJ/m2. These surfaces were prepared through careful experimental procedures that were used for the determination of solid surface tensions from contact angles. Our data for the maximum spreading diameter of water and formamide impacting on these surfaces were compared with those predicted from literature models. Of the models selected, we modified the model of Pasandideh-Fard et al. [Phys. Fluids 1996, 8, 650] and the results yielded a least error of only 5.09 +/- 5.05% in the determination of the maximum spreading diameter. The improved model was also compared with literature data, and good agreement was found. Of course, any such comparisons would rely on accurate experimental impact dynamics data on carefully prepared surfaces. 相似文献
68.
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70.
采用磁控溅射法,以镍硅合金为靶,制备了一种适用于金属诱导横向晶化的氧化物镍源——自缓释镍源.该镍源在内部构成和晶化现象上都不同于纯金属镍源.采用该镍源制备低温多晶硅材料,晶化速率不明显依赖于镍源薄膜的厚度,且晶化多晶硅膜内的残余镍量亦可有效降低,可为薄膜晶体管提供宽的工艺窗口.本文对用纯金属镍源所得多晶硅薄膜的晶化率、表面粗糙度、电学特性等与溅射条件的关系进行了研究,并对相应结果进行了讨论.
关键词:
自缓释
金属诱导横向晶化
多晶硅薄膜
低温制备与退火 相似文献