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901.
Seung Uk Son Do Han Kim Il Gu Jung Young Keung Chung Sueg‐Geun Lee Sung‐Ho Chun 《Journal of polymer science. Part A, Polymer chemistry》2003,41(1):76-83
New norbornene derivatives synthesized from Pauson–Khand reaction products were homopolymerized and copolymerized with norbornene with an allyl–palladium complex as a catalyst. The ketone group was tolerated by the polymerization reaction. Monomers bearing protected alcohols were easily homopolymerized. Most of the homopolymers were soluble in tetrahydrofuran, CH2Cl2, toluene, and cyclohexane. As the steric bulkiness of the substituent increased, the chain length of the homopolymer decreased. Copolymers with a molecular weight of up to 153,800 were formed and were soluble in tetrahydrofuran, CH2Cl2, toluene, and diethyl ether. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 76–83, 2003 相似文献
902.
By using a previously proposed novel integral transform approach, approximate analytical solutions for a certain class of concentration-dependent diffusion and reaction problems can be obtained. Three example problems of increasing complexity are presented to demonstrate the versatility of this technique. Perturbation techniques are also employed to determine asymptotic behaviour of the solutions in the limit of large or small values of some parameters. 相似文献
903.
Zs. Gulacsi M. Crişan M. Gulacsi Al. Anghel 《Journal of magnetism and magnetic materials》1983,37(1):58-62
The stability of the Sherrington-Kirkpatrick model is reconsidered, pointing out that the de Almeida-Thouless line from the phase diagram does not imply the replica symmetry breaking at the zero magnetic field. 相似文献
904.
The GeS8 chalcogenide glass was irradiated by four various doses of fast neutrons. An absorption band has appeared at 450 nm and developed with the neutron doses. It has been concluded that neutral defects are present in the material. From the measurements of the temperature dependence of the d.c. conductivity follows that the activation energy does not depend on the neutron dose within the measured range while the magnitude does with the peak value at neutron dose of 1017 ncm?2. 相似文献
905.
Changes in fluorescence intensity at the far and near side for various spot locations in a sorbent are calculated using a multilayer model and Bodó equations for each sublayer. Flow charts are given for evaluation of reflectance transmission, and fluorescence. 相似文献
906.
907.
908.
动态微粒场诊断用全息光路的设计与分析 总被引:1,自引:0,他引:1
本文分析了动态微粒场测试的特点,设计了一种适合于动态微粒场用脉冲激光全息诊断的全息光路,并从理论上进行了分析。使用这种全息光路记录的微粒场全息图,当用记录参考光,而不是它的共轭光照明再现时,就能获得微粒的实象,因而,使得参考光类型的选择更加灵活。同时,由于光路设计上还考虑了参物光之间的空间相干性的匹配,故降低了对激光器横模的要求。 相似文献
909.
V. K. Yatsimirskii E. V. Ishchenko T. B. Mischanchuk Do Dien Ho 《Theoretical and Experimental Chemistry》1989,24(5):590-592
Thermal desorption was used to study the state of chemisorbed nitrogen on the surface of iron-nickel ammonia-synthesis catalysts in the region of the solid solution of nickel and iron. It was shown that the 1 form of nitrogen should be responsible for catalysis.Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 24, No. 5, pp. 616–618, September–October, 1988. 相似文献
910.