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21.
当今设计住宅、商业等设施时主要考虑建筑物的功能、审美和可建造性,但是建筑物中大量使用的玻璃材料是建筑物结构中较为薄弱的环节,必须要对低概率的自然灾害和恶性供给予以考虑。从现在的大型商场、机场、银行等对安全方面的要求,开始使用了PVB夹层玻璃,而且是先钢化后夹胶的玻璃制品,因此夹层玻璃市场发展前景广阔。针对夹层玻璃的结构和功能,叙述了PVB夹层玻璃的性能和特点、PVB玻璃的产品品种及应用领域,分别介绍了建筑用PVB夹层玻璃和车用PVB夹层玻璃,同时指出了PVB夹层玻璃的市场商机。  相似文献   
22.
The oxygen vacancy levels as a factor on different gadolinia-doped ceria interlayer (GDCi) films deposited on yttria stabilized zirconia (YSZ) electrolyte substrates by an atmospheric pressure plasma jet (APPJ) via precursor solution of nitrate salts are investigated. Focusing on the effect of carrier gases, scanning electron microscopy (SEM), Raman, and X-ray diffraction (XRD) are implemented for the materials characterization of the as-deposited GDCi films and sintered-GDCi films at various temperatures. The higher level of oxygen vacancies in GDCi films adhered on 8YSZ electrolyte are evidently analyzed using Ar as the carrier gas during the deposition, of which the interdiffusion resulted in the formation of (GDC + YSZ) solid solution for sintering over 1300?°C degraded the total conductivity. The deposition of GDCi films on 8YSZ by APPJ method using O2 carrier gas significantly improved the total conductivities of the whole electrolyte layers. Moreover, this study provides the useful insight into the oxygen vacancy levels on GDC films as interlayer (GDCi) to improve the values of open circuit voltage in LSM/GDCi/YSZ/Pt full-cell, as well as offering the efficiency of APPJ as one step deposition process.  相似文献   
23.
针对含软弱夹层岩体爆炸应力波的传播过程,采用数值模拟的方法,探讨了软弱夹层厚度、位置及角度对爆炸应力波传播的影响规律。研究结果表明:爆炸应力波在软弱夹层界面处发生反射,产生的拉伸应力波使应力波能量在迎波面汇聚,加剧该部分岩体的破坏程度。随着软弱夹层厚度的增加,前方岩体拉应力峰值增长作用由近迎波面岩体向炮孔周边岩体传播,拉应力峰值增长率逐渐提高;同时,夹层阻隔作用增强,后方岩体有效应力峰值衰减加快。软弱夹层与起爆中心的间距减小使得夹层前方岩体拉应力峰值显著增长,而对夹层后方岩体的阻隔作用逐渐减弱。应力波能量主要汇聚在软弱夹层的垂直方向,致使岩体爆破产生的裂缝偏离水平测线方向而向软弱夹层法线方向发展。研究成果可用于指导类似地层隧道爆破施工设计。  相似文献   
24.
通过混合焓的计算,对不同共混比和聚合物浓度的聚氯乙烯(PVC)/聚乙烯醇缩丁醛(PVB)共混比体系的相容性进行预测,并通过稀溶液黏度(DSV)法、运动黏度法和目视法进行相应验证;以N,N-二甲基乙酰胺(DMAc)为溶剂,通过湿相转换法(NIPS)制备PVC/PVB共混平板超滤膜,并对超滤膜的性能和结构进行测试,系统地研究了PVC/PVB共混铸膜液的组成对平板超滤膜的结构及其分离性能的影响,为通过PVB共混改性PVC膜材料制备超滤膜提供了理论依据。  相似文献   
25.
The effect of interlayer distance of nanoclay on mechanical properties, cure characteristics, and swelling resistance of natural rubber (NR) in varying clay proportion were studied. X-ray diffraction results of nanocomposite with 10 phr of nanoclay showed the formation of an intercalated structure. The rate of vulcanization and maximum torque value of the nanocomposite are higher than the gum compound. Nanocomposites with clay having higher interlayer distance shows superior mechanical properties. Mechanical properties gradually increase with increase in clay loading up to 10 phr. A 50% increase in tensile strength and about 150% increase in modulus at 300% elongation were observed for the nanocomposite with 10 phr clay loading. Better barrier properties offered by the nanocomposites due to the presence of tortous path was confirmed by the Nielson's model.  相似文献   
26.
近年来,高比能锂-硫电池作为最具前景的新能源储存装置之一引起了人们的广泛关注。然而,在该电池体系中,中间产物聚硫化物的溶解造成的穿梭效应会明显降低电池的循环性能和硫利用率,严重阻碍锂-硫电池的推广应用。综述了近年来石墨烯和石墨烯基复合自支撑中间层材料在锂-硫电池中的应用,例如,通过物理或化学限域的方法减缓多硫化物的穿梭并改善锂-硫电池电化学性能等,并对石墨烯基复合自支撑中间层材料未来在锂硫电池中的实际应用进行了展望。  相似文献   
27.
The shuttle effect of soluble polysulfides is a serious problem impeding the development of lithium−sulfur batteries. Herein, continuous amino-functionalized University of Oslo 66 membranes supported on carbon nanotube films are proposed as ion-permselective interlayers that overcome these issues and show outstanding suppression of the polysulfide shuttle effect. The proposed membrane material has appropriately sized pores, and can act as ionic sieves and serve as barriers to polysulfides transport while allowing the passage of lithium ions during electrochemical cycles, thereby validly preventing the shuttling of polysulfides. Moreover, a fast catalytic conversion of polysulfides is also achieved with the as-developed interlayer. Therefore, lithium−sulfur batteries with this interlayer show a desirable initial capacity of 999.21 mAh·g–1 at 1 C and a durable cyclic stability with a decay rate of only 0.04% per cycle over 300 cycles. Moreover, a high area capacity of 4.82 mAh·cm–2 is also obtained even under increased sulfur loading (5.12 mg·cm–2) and a lean-electrolyte condition (E/S = 4.8 μL·mg–1).  相似文献   
28.
In the present study, diffusion bonding of two dissimilar materials TC6 and copper alloy was investigated in vacuum chamber by directly bonding and using Ni foil as interlayer. Interface quality of the joints was evaluated by mechanical property and microstructure. The maximum shear strength of directly bonding was found to be 64 MPa for the speciemen bonded at 850 °C, 5 MPa for 30 min; and the maximum shear strength with Ni foil interlayer was 113 MPa under the same bonding parameters. The bonding interfaces and fracture surfaces were analyzed by energy disperse spectrometer, scanning electron microscopy and X-ray diffraction. The results show that the diffusion region of directly bonding specimen generated several IMCs (Ti2Cu and Ti5CuSn3, etc.). Fracture morphology showed that brittle fracture present at the Ti5CuSn3 IMCs, which was the weak point of the joint. While the diffusion zone of the specimen with Ni foil interlayer consists of various phase including Ti2Ni, TiNi, TiNi3 at TC6 side, and Cu-Ni solid solution at ZQSn11-4-3 side, and fracture surface of joint present a mixture of brittle and ductile characteristics, and fracture initiated at the TiNi3/Ni interface.  相似文献   
29.
Lu-Al-Si-O-N tapes with different thickness were used to join gas pressure sintered Si3N4 ceramics. The microstructure of the joints and the influences of the joint thickness and joining temperature on the bonding strength of the as-joined Si3N4 ceramics have been investigated. The highest bonding strength about ~ 300 MPa of the joined specimens was achieved by using 450 µm interlayer at 1450 °C. The existence of Si3N4 nanowires was beneficial for the improvement of the bonding strength by interweaving the oxynitride glass matrix in the joint region.  相似文献   
30.
Applying the Taguchi method of experimental design, we prepared various polyamide 6 (PA6)/acrylonitrile butadiene rubber (NBR)/nanoclay nanocomposites under different processing conditions by melt mixing in an internal mixer. The effects of the processing variables, including the rotor speed, chamber temperature, and mixing order on the morphology, that is, the rubber particle size and interlayer distance, and the mechanical properties, that is, the tensile modulus and impact strength, were then investigated. As demonstrated with the Taguchi approach, the lower temperature associated with higher rotor speeds improved the mechanical properties of the 90/5/5 PA6/NBR/nanoclay systems. However, it was revealed that the mixing order did not affect the mechanical properties for the assigned composition. Hence, the simultaneous mixing of all the ingredients is seemingly the simplest way of mixing to obtain the desired mechanical properties. These results were confirmed with transmission and scanning electron microscopy observations and X‐ray diffraction measurements. Image analysis corresponding to the mean particle size of the NBR constituent was also performed. The optimum processing condition to achieve the appropriate mechanical properties is ultimately predicted by the Taguchi analysis and corresponded to a chamber temperature of 230°C and a screw speed of 80 rpm. Moreover, the simultaneous mixing of all of the ingredients was suggested for convenience. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 820‐828, 2013  相似文献   
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