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61.
介绍砌块仿花岗岩挡土结构的特点和砌块形状,针对砌块挡土结构在我国刚开始应用,没有设计、施工规范的现状,依托可以借鉴的加筋挡土结构和浆砌块石挡土结构设计规范,提出了自锁式砌块加筋挡土结构设计中的地面荷载强度及土压力计算方法、砌块层间稳定验算方法、加筋长度和间距验算方法、挡土结构整体稳定验算方法和施工过程中需要注意的主要问题,为自锁式砌块加筋挡土结构设计人员提供了设计验算内容、验算方法和安全系数取值范围,为现场施工和监理人员提供参考,并为该类型的挡土结构推广应用提供技术支持。 相似文献
62.
The durability of a cold wall MHD generator consisting of metal electrodes and alumina-coated peg insulators was experimentally examined in the oil-fired MHD condition with the additive of SO2 corresponding to S = 0.54 wt%. The structure of the electrode wall and various anode and cathode materials were tested, with particular reference to developing long-life electrodes. It was clarified that Pt, SHOMAC (28.8 Cr−1.9 Mo) and SUS-304 as anodes and W---Cu (70 W−30 Cu) and WC---Ag (60 WC−40 Ag) alloys as cathodes were promising for durability and that the structure of an anode divided into two elements connected to each other with an SnO2 resistor was very useful for uniformity of the anode corrosion pattern and the inter-anode voltages. It is reasonable to expect, from the test results, that the lifetime of a cold wall MHD generator in an oil-fired commercial plant will be over 4000 h, and therefore, a foundation for its commercial use has been established. 相似文献
63.
A protein which masks galactose receptor mediated phage susceptibility in Lactococcus lactis subsp. lactis MPL56 总被引:1,自引:0,他引:1
Yasin Tuncer & Mustafa Akçelik 《International Journal of Food Science & Technology》2002,37(2):139-144
A 28.5-kb plasmid, isolated from Lactococcus lactis subsp. lactis MPL56, causes complete inhibition of four lactococcal phages. Cell wall characteristics of wild-type strain MPL56 were compared with its 28.5 kb plasmid-cured, phage-sensitive derivative MPL56-22. After proteolytic enzyme treatments, adsorption of phages occurred at high levels, an example is 94.6–98.5% in MPL56 cells. Analysis of cell wall extracts of MPL56-22 by sodium dodecyl sulphate–polyacrylamide gel electrophoresis (SDS–PAGE) indicated that the only difference between strains was the 55.4 kDa band in protein patterns of MPL56. Adsorption of the four phages was completely inhibited when MPL56-22 cells were subjected to SDS, Triton-X-100, HCl and NaOH treatments. Lectins that were specific for glucose/mannose and N-acetylglucosamine did not prevent adsorption of phages in cell wall extracts of MPL 56-22. However a lectin specific for galactose (MCA; Momordica charantia ) completely inhibited adsorption of these phages in cell wall extracts of MPL56-22. HPLC patterns of cell wall carbohydrates of MPL56-22 and its HCl treated preparations showed that the most prevalent difference was the galactose on untreated MPL56-22 cell wall chromatograms. 相似文献
64.
65.
分析了住宅室内材质的功能与表现,介绍了室内材质的设计原则以及室内材质协调的基本规律,例举了住宅室内材质的合理运用,以展现出人性化的居住空间。 相似文献
66.
A. Kadashchuk A. Andreev H. Sitter N.S. Sariciftci Y. Skryshevski Y. Piryatinski I. Blonsky D. Meissner 《Advanced functional materials》2004,14(10):970-978
We report on photoluminescence (PL) and thermally stimulated luminescence (TSL) in highly ordered nanostructures of para‐sexiphenyl (PSP) grown by hot wall epitaxy (HWE). A low‐energy broad band is observed in the PL spectra that can be attributed to the emission from molecular aggregates. While the intrinsic exciton emission in steady‐state PL dominates at low temperatures, the emission from aggregates increases with elevating temperature and its magnitude depends sensitively on film preparation conditions. Time‐resolved PL measurements showed that the aggregate emission decays with a life‐time of ≈ 4 ns, which is approximately an order of magnitude larger than the lifetime of singlet excitons. TSL data suggests the presence of an energetically disordered distribution of localized states for charge carriers in PSP films, which results from an intrinsic disorder in this material. A low‐temperature TSL peak with the maximum at around 30 K evidences for a weak energy disorder in PSP films, and has been interpreted in terms of a hopping model of TSL in disordered organic materials. 相似文献
67.
Unconrolled agglomeration of particles and adhesion of the particulate mass to wall surfaces are common severe problems in many drying operations. This paper reviews the mechanisms of interparticle and particle-surface attraction as well as the theory and the existing tests for characterising powders in terms of internal strength, wall friction and adhesion. The usefulness of the information obtained from these tests in dryer design and operation is critically reviewed. The importance of powder stickiness in various types of dryers is discussed and established methods of combating the problem are presented Recommendations an made for further research in the area of powder cohesion and adhesion. 相似文献
68.
东荣三矿冻结段井壁破坏原因简析 总被引:1,自引:0,他引:1
介绍了东荣三矿主井、副井、东风井三个井筒冻结段井壁的施工及破坏情况,并针对破坏的原因进行了分析,同时对冻结段的井壁结构型式提出了建议。 相似文献
69.
本文提出一种可控环量船用翼数值模拟方法,其计算结果与最近Mclachlan的试验数据十分吻合。通过本文的计算,对广泛引用的Kind & Maull的二维试验数据提出了修正。根据本文所作的三维可控环量帆翼的试验结果,与二维计算值的比较,指出它们之间所存在的显著差别。 相似文献
70.
运用文献[1]所介绍的分析原理与方法,编制了强震作用下钢筋混凝土框架-剪力墙结构非线性地震反应时程分析的程序。本文介绍该程序的功能、框图,以及利用该程序计算所得到的几栋钢筋混凝土结构的非线性地震反应分析结果。算例表明,本程序计算结果可靠,能很好地用于解释震害和预测地震时结构可能发生的破坏。 相似文献