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991.
对卫生间硅酸钙板轻质隔墙上采用瓷砖饰面系统进行了相关应用性研究,讨论了硅酸钙板厚度、界面处理、防水处理以及粘贴材料等对系统粘结力的影响,提出了在硅酸钙板轻质墙体上进行瓷砖饰面的可靠施工方案。 相似文献
992.
ABSTRACTThe versatility of polymer matrix composites in industrial applications has gained reputation and adaptability among advanced materials. Still, treatment of reinforcement for these composites has emerged as a vital domain to be explored. With a continuance to this fact, the present paper aims to analyze the effect of reinforced electroless coated silicon carbide particulates on mechanical properties of composites. The composite is developed using epoxy polymer as matrix and glass fibers as primary reinforcement. The electroless coated and uncoated silicon carbide particulates were used as secondary reinforcement. The phase identification of copper on secondary reinforcement was identified using X-ray powder diffraction technique. Fracture analysis during tensile testing and bonding behavior between matrix and reinforcement is examined using field emission scanning electron microscopy with energy dispersive spectroscopy. The presence of copper particles on secondary reinforcement results in improved interfacial bonding and resistance against fracture during loading. 相似文献
993.
994.
《Measurement》2016
This paper presents the design of a novel Ground-Penetrating Radar (GPR) test site that has been integrated into the mini-city demonstrator Sense-City located at University Paris-Est (France). This test site provides several sources of measurement interest expressed by the presence of a multilayered soil with significant dielectric contrasts, and various dielectric pipes and blades buried at various depths in trenches filled with a backfill soil different from the natural soil. This paper presents experimental Bscans associated with the pipe zone acquired by three different GPR systems at frequencies ranging from 300 MHz to 1.5 GHz. The interpretation and comparison of the raw Bscans have allowed to characterize the dielectric properties of the soil layers, and to detect the hyperbola signatures of the buried pipes. The results of this study will help to guide future developments on polarization, operating frequency and signal processing to extract parameters (orientation, dielectric characteristics, position and size) associated with pipes. 相似文献
995.
Jianfeng Li Ben Freireich Carl Wassgren James D. Litster 《American Institute of Chemical Engineers》2012,58(5):1397-1408
In this work, a general multidimensional population balance (PB) model is developed to predict the coating volume distribution on polydisperse particles as a function of time during particle coating in a paddle mixer. The model adopts a compartmental approach to account for coating variation caused by particle flow heterogeneity. Simulations show that for a realistic range of seed particle size polydispersity and coating mass applied, the coating volume distribution depends on the growth rate exponent and seed particle size distribute on, with the coating volume coefficient of variance (CoV) approaching an asymptotic value as the coating‐to‐particle volume ratio increases. These effects cannot be predicted by simpler one‐dimensional models. However, the full two‐dimensional PB and simpler one‐dimensional models such as Mann's equation do predict similar sensitivity of coating volume CoV to the variation in the compartment model parameters, i.e., to changes in the particle mixing behavior in the vessel. © 2011 American Institute of Chemical Engineers AIChE J, 2012 相似文献
996.
M.A. Darwish H.F. Abosheiasha A.T. Morchenko V.G. Kostishyn V.A. Turchenko E.L. Trukhanova K.A. Astapovich A.V. Trukhanov 《Ceramics International》2021,47(12):16752-16761
Rapid developments in information technologies and a large rise in electrical and electronic equipment have generated different forms of electronic environmental contamination. Microwave absorption materials are important to avoid the damage that can be caused by electromagnetic radiation. A necessary condition for the absorption of the most incoming radiation is balanced wave impedance at the air/shield interface, which depends on the studied materials' magnetic and electrical properties. The paper introduces the preparation of BaFe12-xZrxO19 (x = 0.1, 0.3, 0.6, 0.9, and 1.2) using a solid-state reaction technique. The studied samples were examined by X-ray diffraction, scanning electron microscopy, vibrating sample magnetometer, and a vector network analyzer. The studied samples showed that controlling the grain size and the prepared samples' magnetic properties play an important role in enhancing the microwave radiation absorption. The examined samples can be a promising absorption material in electromagnetic shielding applications. 相似文献
997.
Evaluation of fire performance of organic fire retardant free acrylic based coatings applied on various building materials by cone calorimetric method
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Fire performance of water‐based plaster systems containing acrylic copolymer binder and non‐flammable mineral and ceramic fillers intended for decorative coating application was determined by cone calorimetric method. The coatings were applied on common building substrate materials used in construction sector, namely, Medium Density Fibre (MDF) boards, Gypsum Boards (GIB) and Stainless Steel (SS), and the different plaster finishes attempted on these substrates were Tierrafino, Suave and Bone China respectively. Group numbers of the different test samples were also evaluated following the Kokkala method. Based on various measurements, especially heat release, smoke evolution, mass loss data and the Group number estimates, it is evident that these organic fire retardant free coatings can offer good fire safety if applied on appropriate substrates like GIB or SS. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
998.
999.
Yaosha Wu Dechang Zeng Zhongwu Liu Wanqi Qiu Hongya Yu Xichun Zhong Shangzhou Li Yuexin Ma 《稀有金属(英文版)》2012,31(2):204-208
A pseudo-alloy PS45/CuAl8 composite coating was sprayed on steel substrate by high-velocity activated arc spraying (HVAA) process. Its sliding wear behavior at room temperature was evaluated by M-2000 wear tester. For comparison, a single CuAl8 coating was also prepared and tested under the same conditions. It is found that the pseudo-alloy composite coating consists of α-Cu and γ-Ni metallic matrix phases together with homogenously distributed minor Al 2 O 3 , Cr 2 O 3 oxide phases. Moreover, pseudo-alloy coating possesses much better sliding wear resistance than CuAl8 coating due to the enhanced hardness and microstructural homogenization. Fatigue wear and abrasive wear are responsible for the wear-down mechanism of the pseudo-alloy coating. 相似文献
1000.
《Journal of the European Ceramic Society》2014,34(11):2687-2694
The spallation resistance of an air plasma sprayed (APS) thermal barrier coating (TBC) to cool-down/reheat is evaluated for a pre-existing delamination crack. The delamination emanates from a vertical crack through the coating and resides at the interface between coating and underlying thermally grown oxide layer (TGO). The coating progressively sinters during engine operation, and this leads to a depth-dependent increase in modulus. Following high temperature exposure, the coating is subjected to a cooling/reheating cycle representative of engine shut-down and start-up. The interfacial stress intensity factors are calculated for the delamination crack over this thermal cycle and are compared with the mode-dependent fracture toughness of the interface between sintered APS and TGO. The study reveals the role played by microstructural evolution during sintering in dictating the spallation life of the thermal barrier coating, and also describes a test method for the measurement of delamination toughness of a thin coating. 相似文献