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1.
介绍了单层防水卷材机械固定屋面系统的特点、应用范围、材料要求、设计与施工要点等.从现行屋面规范和节材的角度对发展该屋面系统提出了建议。 相似文献
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虹桥机场西航站楼屋面形式有混凝土和轻钢两种,设计分别选用了西卡渗耐的PVC卷材满粘系统和机械固定系统。本文从材料选择、系统理论依据、节点处理等方面分别介绍了这两种单层屋面系统技术,指出整个屋面防水系统使用效果良好。 相似文献
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纳、微米Al2O3颗粒混杂增强铝基复合材料的磨损性能 总被引:1,自引:0,他引:1
利用搅拌摩擦加工(FSP)制备纳、微米氧化铝颗粒单一增强以及混杂增强的A356铝基复合材料,并在摩擦磨损试验机上考察其磨损性能。结果表明,在0.5~3.0 MPa载荷范围内,在相同载荷下,混杂复合材料的磨损量都低于两种单一增强的复合材料;在不同载荷下,随着载荷的增加,复合材料的磨损量都增加,但是混杂颗粒增强复合材料的增加最快,微米颗粒增强复合材料最慢;复合材料的磨损机制主要是磨粒磨损和剥层磨损;在复合材料磨损亚表层都发现机械混合层的存在,对复合材料的耐磨性有一定的影响。 相似文献
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Satoshi Kaneko 《Fullerenes, Nanotubes and Carbon Nanostructures》2014,22(1-3):166-172
A pyrazine molecular junction was investigated using mechanically controllable break junction (MCBJ) technique at 10 K. The conductance measurements revealed the single pyrazine molecular junctions showed two distinct conductance values of 0.27 ± 0.04 and 1.0 ± 0.2 G 0 (2e 2/h). The conductance value of the single pyrazine molecular junction was comparable with that of the metal atomic junction. The interface between pyrazine molecule and Pt surface was investigated by near edge X-ray absorption fine structure (NEXAFS). The broadening of the π* peak in N K-edge NEXAFS spectra suggested that the pyrazine molecule connected to Pt surface via a nitrogen atom. Based on the measurements of the conductance and NEXAFS, we could propose the structural models of two distinct conductance states for the single pyrazine molecular junction. 相似文献
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J. Yuste R. Pla M. Capellas E. Sendra E. Beltran M. Mor-Mur 《Journal of food science》2001,66(3):482-484
The effect of oscillatory high pressure processing on mesophile and psychrotroph populations of mechanically recovered poultry meat (MRPM) was evaluated. Vacuum‐packaged samples were subjected to cycles by alternating moderate pressure (60 MPa) and high pressure (450 MPa) at 20 °C, once or several times so that the total time under high pressure was 15 min. A continuous treatment at 450 MPa for 15 min at 20 °C was also performed. Oscillatory treatments did not generate significantly higher decreases in counts of both populations than continuous pressurization. Reductions from 3.2 to 3.8 log CFU g–1 were found for mesophiles. Psychrotrophs proved more sensitive: one of the cyclic treatments induced a lethality of 5.2 log CFU g –1. Pressurization improves the microbiological quality of MRPM. 相似文献
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Blends of uncrosslinked styrene-butadiene rubber (SBR) with a terpene tackifier resin or a naphthenic oil have been characterized, and their autohesion and cohesion determined using a T-peel geometry. SBR/oil blends are homogeneous at all proportions, while SBR/resin blends, based on DSC and DMA analysis, undergo bulk phase separation at about 50% resin. However, migration of tackifier to the surface region is proposed at much lower resin contents. Compositions diluted with oil have autohesion similar to the neat SBR. This is attributed to compensating effects; although oil hastens self-bond formation by increasing chain mobility, this is nearly equally balanced by more facile chain separation during bond rupture. In short, oil-diluted compositions are soft and weak. On the other hand, SBR compositions containing small amounts of resin have high autohesion. Resin-diluted specimens deform easily at low strain, just as those containing oil, but intertwined chains of the former have greater resistance to separation, due at least in part to higher glass transition temperatures. It is proposed that autohesion is further enhanced by migration of tackifier to the surface. This causes SBR/resin compositions to be both soft and strong-a necessary condition for high autohesion. 相似文献
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