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131.
Shagapov V. Sh. Galiakbarova É. V. Khakimova Z. R. 《Journal of Engineering Physics and Thermophysics》2021,94(3):678-686
Journal of Engineering Physics and Thermophysics - A study is made of the evolution of pulsed pressure perturbations in a pipeline filled with a gas–droplet medium, which represents... 相似文献
132.
A method is proposed to monitor the shape of an atomic force microscope tip, which can combine the operations of ion etching
and shape monitoring, by using the intensity of the backscattering of ions from the same or a different beam to monitor the
shape. Relationships have been obtained to monitor the shape of the probe using the measured dependence of the backscattering
intensity on the parameters of the incident beam.
Pis’ma Zh. Tekh. Fiz. 23, 88–92 (June 12, 1997) 相似文献
133.
134.
Possibilities of polynomial techniques for synthesizing and analyzing a robast control system of dc thyristor electric drivers
are considered. It is shown that the use of the suggested techniques makes it possible to decrease the sensitivity of a controlled
electric drive to parametric, structural, and external disturbances by about an order of magnitude. A technique for optimizing
the parametric sensitivity of the quality factors is suggested. 相似文献
135.
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137.
Syed Safdar Ali Khalid Mohammed Khan Hartmut Echner Wolfgang Voelter Mashooda Hasan Atta-ur-Rahman 《Advanced Synthesis \u0026amp; Catalysis》1995,337(1):12-17
Two new synthons, Fmoc-L-Arg(biphenyl-4-sulphonyl)-OH ( 8 ) and Fmoc-Arg(4-methoxy-3-t-butylbenzenesulphonyl)-OH ( 14 ), are prepared for the synthesis of arginine-containing peptides. These groups are cleaved by commonly employed trifluoroacetic acid and methanesulphonic acid. Kinetic studies reveal that extended bicyclic aromatic conjugation, as in biphenyl, slightly improves the acid lability compared to the electron-donating t-butyl group. 相似文献
138.
Industrialization has led to a number of environmental problems, such as release of toxic metals and other toxic organic and inorganic compounds to the environment. Among all, the rapid expansion of leather related industries in Pakistan have resulted in considerable environmental problems and effluents from processing of both domestic and imported hides and skins have increased pollution to alarming levels. Some tannery effluents of Peshawar area investigated in the present study showed high concentrations of Cr(Ⅵ) (2.7-12.6 mg/L), Cu(Ⅱ) (2.6-11.4 mg/L) and phenol (0.1-4.2 mg/L). These contaminants are very toxic and must be removed from effluents before releasing into water bodies. A new technique of gamma irradiation has been investigated to decrease the load of COD and concentrations of Cr(Ⅵ), Cu(Ⅱ) and phenol associated with tannery effluents to the permitted values. It was observed that concentration of Cr(Ⅵ) in the effluents can be brought to the permitted level by applying radiation dose of 3 kGy. A radiation dose of 2.5 kGy was required to remove more than 95% of Cu(Ⅱ) and 100 % degradation of phenol in tannery effluents could be achieved by only one kGy of radiation dose. 相似文献
139.
T Sh Sharmanov I A Kurmangalinova S A Nikitin G Ia Chernov S M Kurmangalinov 《Voprosy pitaniia》1987,(6):39-42
A mathematical model of the mechanism of development of orally induced immunologic tolerance has been suggested. The model presents a system of differential non-linear equations, and it is realized as a program in FORTRAN. The model describes primary and secondary immune responses, reflects the main features of the immune system response to antigen intake with food. The immune system model response to varying doses and frequency of the antigen intake with food has been studied. It has been established that repeated administration of small doses of the food antigen leads to a deeper tolerance due to lower stimulation of the immune system. The existence of optimal tolerogenic doses of the food antigen has been proved. Qualitative changes in the immune system response to the food antigen have been recorded in case of increased permeability of the intestinal wall. 相似文献
140.
复杂环境下砖砌烟囱的爆破拆除 总被引:1,自引:0,他引:1
本文介绍了采用定向爆破拆除一座砖砌烟囱的施工设计方法,包括爆破方案选择、爆破切口设计和爆破安全验算等内容,对类似工程有一定的参考意义。 相似文献