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41.
Dianov E.M. Grudinin A.B. Gurjanov A.N. Gusovsky D.D. Harutjunian Z.E. Ignatev S.V. Smirnov O.B. 《Lightwave Technology, Journal of》1992,10(2):118-124
The reproducible technology for producing high-birefringence fibers with stress-induced elliptical cladding and circular core is described. The authors have obtained fibers that have a birefringence of about (1-3) 10-4, a mode coupling parameter of about (2-7) 10 -5 m-1, and loss of less than 0.5 dB/km at 1.6 μm. The authors have found effects restricting the capability of test fibers to maintain the state of linear polarization 相似文献
42.
Z. M. Sun Z. G. Wang H. Hdl B. Weiss R. Sticker 《Materialwissenschaft und Werkstofftechnik》1995,26(9):483-487
The deformation behavior of pure recrystallized molybdenum under cyclic and static loads was investigated in the temperature range between 30°C and 10O°C, for stress amplitudes between 100 MPa and 250 MPa and for static loads up to 200 MPa. The results show that in spite of the low test temperatures and stress levels the Mo material exhibits considerable plastic strains which depend sensitively on frequenez and small changes in temperature.The activation energy deduced for the static and dynamic deformation is less than 0.98 eV which indicates thermally activated processes, to be explained by a dislocation kink model as described in the literature. The low-temperature fatigue behavior appears strongly influenced by creep-fatigue interaction phenomena. 相似文献
43.
Under serum-free conditions the beta-glucan receptor of mouse macrophages mediates phagocytosis of beta-1,3-D-glucan-coated microbeads (diameter 2 microns). IFN-gamma increases the phagocytic function of the beta-glucan receptor in a dose-dependent manner, giving the plateau level at 100 U/ml. Maximum activity appears 9 h after addition of IFN-gamma to the cells. The effect disappears within 24 h. The effect of IFN-gamma may be a result of augmented receptor synthesis since treatment with cycloheximide reduces the phagocytosis. IL-1 also increases the phagocytic function of the beta-glucan receptor giving a dose-dependent response and with the plateau level reached at 10 U/ml. Maximum activity is found 4 h after addition of IL-1 to macrophages. The effect disappears within 24 h. TNF does not alter the phagocytic function of the beta-glucan receptor, but TNF together with IL-1 prolongs the effect of IL-1. PGE2 reduces the phagocytic function of the beta-glucan receptor. Maximum reduction is achieved with 8 ng/ml. Time-course studies show the lowest phagocytic activity 9 h after addition of PGE2 to the cells. 相似文献
44.
精选了一系列有机和无机化合物为成核剂,使用砂浴法和热台法制备了一系列不同β晶含量的等规聚丙烯,发现最有效的β成核剂是溶靛素灰 IBL 和溶蒽素金黄 IGK,首次表明β成核剂具有排列紧密的稠球结构特征,且含有硫原子。 相似文献
45.
Continuing our work on the immunosuppressive activity of cyclolinopeptide A (CLA), a cyclic nonapeptide of the sequence: c-(-Leu-Ile-Ile-Leu-Val-Pro-Pro-Phe-Phe), we synthesized a series of 6 linear analogs of CLA, successively shortened at the N-terminus of the peptide chain. Immunosuppressive activity of acetates as well as trifluoroacetates of these peptides was investigated using PFC (humoral immunity) and DTH (cellular immunity) tests. It was found that the immunosuppressive potency of the peptides examined diminishes with shortening of the peptide chain. Octapeptide I with the sequence Ile-Ile-Leu-Val-Pro-Pro-Phe-Phe was found to be the most active of the whole series. The immunosuppressive activity increased again for a tripeptide fragment of CLA of the sequence Pro-Phe-Phe. The immunosuppressive activity of octapeptide probably depends on the suppression of IL-1, IL-6 and TNF production by the cells involved in immune and inflammatory response. 相似文献
46.
R. Z. Gataulin 《Chemical and Petroleum Engineering》1992,28(8):519-521
Translated from Khimicheskoe i Neftyanoe Mashinostroenie, No. 8, pp. 31–32, August, 1992. 相似文献
47.
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49.
Casacca M.A. Capobianco M.R. Salameh Z.M. 《Energy Conversion, IEEE Transaction on》1996,11(1):139-145
Battery storage is a crucial element in alternative energy and electric vehicle systems. Three battery storage configurations: a conventional; a parallel; and a dual, were analyzed for both shallow cycle and deep cycle lead-acid batteries to determine if capacity improvement is achievable. Daily profiles for the weekly irradiance, daily loads, and ambient temperature are simulated. Cycle tests were performed monthly to determine the effect each configuration had on the available battery capacity. Results for each battery type differ. Available capacity was improved using the parallel configuration with shallow cycle batteries and the dual configuration with deep cycle batteries 相似文献
50.