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1.
1 INTRODUCTION Carbon nanotubes have many potential applica- tions due to their unique structures and properties[1~4]. Physicists have been studying their electrical, me- chanical and other properties since their discove- ries[5, 6]. Recently, chemists are interested in carbon nanotubes because their properties can be altered by chemical functionalization[7~14], and these functiona- lized nanotubes can undergo further chemical trea- tment. So the potential application range of such na- … 相似文献
2.
针对柱面注浆方式,研究了有关渗透注浆的单孔复注及不同方式布孔时多孔注浆的相互影响等问题,推导出一些有价值的岩体注浆理论公式,可用于指导现场注浆工程的设计与施工. 相似文献
3.
4.
本文简述了乳浓聚合动力学研究的进展,着重于澳大利亚Sydney大学Gilbert等在乳液聚合阶段Ⅱ动力学方面的研究概况。介绍了不同水溶性单体的小尺寸种子乳液体系的SmithEwart递推方程的求解方法及其解析解形式和乳液聚合动力学数据的处理。同时讨论了该研究的局限性。 相似文献
5.
Summary The detachment of a rubber matrix from a rigid inclusion under monotonic loading and at subsequent relaxation is investigated within two dimensional analysis. Examined are stress–strain experimental data acquired with the help of a test bed equipped with a digital image-acquisition device. The influence of the interfacial bonding strength and the particle size on the detachment process is analyzed. The influence of the interfacial bonding strength is visible in the stress–strain diagram of loading and in the recorded images. The relaxation test reveals no influence of the bonding strength on the stress-relaxation. However, the image analysis indicates a secondary transient creep of the contour of detachment, which depends on the interfacial bonding. 相似文献
6.
本文讨论嵌套病例对照研究中相对危险率的估计问题,引入了相对危险率的两步估计,并在一般嵌套病例对照抽样的假设下讨论了相对危险率的两步估计的相合性问题,最后给出了几个例子。 相似文献
7.
Jon Samseth Richard J. Spontak Kell Mortensen 《Journal of Polymer Science.Polymer Physics》1993,31(4):467-474
Poly(siloxaneimide) (PSI) segmented copolymers exhibit organized microdomains if the blocks are sufficiently incompatible. As with neat diblock and triblock copolymers, the processing route employed to prepare films of PSI materials is expected to influence the dimensions and/or morphology of the resultant microstructure. In this work, small-angle neutron scattering (SANS) is utilized to characterize the disordered microstructure found in films of a series of PSI copolymers which are subjected to solvent casting and various thermal treatments. Microstructural dimensions such as the periodicity and correlation length are deduced from the Teubner-Strey (TS) model for disordered microemulsions. The scattering intensity of each copolymer up to q = 5.0 nm?1, where q is the scattering vector, is found to scale as q?2.8+?0.1. Results indicate that processing the materials as cast films or as melt-pressed films allowed to cool slowly has a small, but discernible, effect on microstructural characteristics. SANS profiles of films quenched from elevated temperatures reveal a clear transition in microdomain periodicity, which correlates well with the glass transition temperature of the imide microphase in these and other materials of similar chemical structure. © 1993 John Wiley & Sons, Inc. 相似文献
8.
Alkynyl-substituted indene was first used as a ligand for the synthesis of transition metal complexes. ansa-Zirconocenes containing ethylene and dimethylsilylene bridges were synthesized starting from 2-(phenylethynyl)-1H-indene. The structure of the former compound was established by X-ray diffraction.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 68–73, January, 2007. 相似文献
9.
A. A. Korlyukov K. A. Lyssenko M. Yu. Antipin A. G. Shipov O. A. Zamyshlyaeva E. P. Kramarova Vad. V. Negrebetsky S. A. Pogozhikh Yu. E. Ovchinnikov Yu. I. Baukov 《Russian Chemical Bulletin》2004,53(9):1924-1931
The reaction of 4-(2-hydroxybenzoyl)-2,2,6,6-tetramethyl-2,6-disilamorpholine with BF3Et2O afforded (O-B)-chelate 4-[2-(difluoroboroxy)benzoyl]-2,2,6,6-tetramethyl-2,6-disilamorpholine. Treatment of the latter with BF3Et2O or SOCl2 gave rise to products of the disilamorpholine ring opening, viz., (O-B) chelate 2-(difluoroboroxy)-N,N-bis(dimethylfluorosilylmethyl)benzamide or 2-(difluoroboroxy)-N, N-bis(dimethylchlorosilylmethyl)benzamide, respectively. The structures of the compounds synthesized were confirmed by X-ray diffraction analysis and 1H, 13C, and 29Si NMR spectroscopy. High-precision X-ray diffraction study and quantum-chemical calculations demonstrated that the coordination OSi bond is absent in the two last-mentioned compounds.Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1846–1853, September, 2004. 相似文献
10.
D. N. Dybtsev M. P. Yutkin E. V. Peresypkina A. V. Virovets Y. Hasegawa H. Nishihara V. P. Fedin 《Russian Chemical Bulletin》2007,56(9):1782-1786
The reaction of Co(NO3)2·6H2O with 1,3,5-benzenetricarboxylic acid (H3btc, trimesic acid) in DMF at 100 °C afforded the coordination polymer [Co3(dmf)6(btc)(Hbtc)(H2btc)]··9H2O (1) (dmf is N,N′-dimethylformamide, DMF). According to the X-ray diffraction study, the metal-organic coordination polymer is composed of
planar honeycomb (6,3) networks, in which the organic benzenetricarboxylate anions and the inorganic Co2+ cations play a role of three-connected nodes. Disordered water molecules are intercalated between the layers. A study of
the magnetic properties showed the presence of a weak antiferromagnetic coupling between the Co2+ ions (S = 3/2).
Dedicated to Academician G. A. Abakumov on the occasion of his 70th birthday.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1719–1723, September, 2007. 相似文献