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31.
在高校信息网络中心机房升级改造中,不间断电源系统的规划应结合实际,兼顾可靠性和有用性的基础上,充分考虑冗余性、可管理性、可扩展性、可维护性、节能环保等基本要素,合理设计不间断电源系统配置,达到降低投资成本,提高系统的可靠性,减少能源消耗量的目标。 相似文献
32.
In civil and mining operations that involve ground excavation and support, the loads are distributed between the ground and support depending on their relative stiffness. This paper presents the development of conceptual single-degree-of-freedom models, which are used to derive equations for estimating displacements and stresses for ground-support interaction problems encountered in pillars in room-andpillar mining(natural support system), and liners for circular vertical shafts(artificial support systems).For pillar assessment, mine-pillar interaction curves can be constructed using a double spring analogy.Additionally, the effectiveness of different support systems can be evaluated depending on their effect upon the mine-pillar system. For shaft design, an initial estimation of the required lining strength and thickness can be readily made based on a double ring analogue. For both problems, the results from the proposed approach compare well with those obtained by finite element numerical simulations. 相似文献
33.
本文以某酒店为例,通过对业主指定的标准间客房进行用电设备能耗分析,利用智能化控制技术结合节能管理措施,按照业主提出的节能目标进行了精细化节能规划设计,在理论上完全实现了节能目标。 相似文献
34.
The shared housing sector is a growing private rental submarket. Researchers have sought to analyse the drivers of this growth, the benefits of shared housing for tenants, landlords and wider urban systems, as well as risks for tenants and local planning systems. Yet, there is limited research exploring the diversity of the shared housing sector. In particular, analysis of room or space sharing with non-related adults is lacking. This paper explores the characteristics, geography and impact of room sharing across Sydney. By analysing online accommodation listings this paper provides insights for policymakers seeking to monitor and regulate shared room accommodation. 相似文献
35.
《Ceramics International》2020,46(5):5706-5714
In this study, we synthesized nanostructured zinc oxide (ZnO) by using various concentrations (0–0.05 M) of cetyltrimethylammonium bromide (CTAB) as a surfactant to optimize its morphology for gas sensor applications. The optimization process was used to elucidate the morphology effects (rod-shaped and flower-shaped morphologies). The morphologies were investigated through scanning electron microscopy, in which the assembly of nanorods leading to a spherical microstructure with a CTAB concentration of 0.005 M was observed. Brunauer–Emmett–Teller isotherm measurements revealed a surface area of 7.928 g/m2 for the flower-like morphology, which was relatively higher than those of other CTAB-assisted morphologies. Such morphological features were expected to contribute toward high-performance gas-sensing. The effect of morphology variation on the resistance of ZnO microstructures was used for gas measurements. Among the varied morphologies, a sample with a spherical flower-shaped morphology exhibited a very high response at low temperatures (~29 at 25 °C) toward NOX gas (0.75 ppm) and a high selectivity toward NOx among ammonia (NH3), toluene (C6H5CH3), carbon monoxide (CO), acetone (CH3COCH3), and ethanol (C2H5OH). Raman and photoluminescence spectroscopy analyses unraveled the presence of a high density of oxygen vacancies in the sample, thereby suggesting a close link between the defective nature of the sample and the high response of the flower-like ZnO at low temperatures. 相似文献
36.
为提高PS-PVD热障涂层的抗沙尘冲刷性能,采用等离子喷涂-物理气相沉积技术(PS-PVD)在粘结层表面制备7YSZ热障涂层,在大气环境下进行了抗沙尘冲刷试验,研究了PS-PVD热障涂层的冲刷行为及失效机制。通过等离子喷涂技术(APS)在PS-PVD热障涂层表面制备了一层致密层状涂层,重点研究了致密层厚度对PSPVD热障涂层抗冲刷失效性能的影响。结果表明PS-PVD热障涂层冲刷过程经历了快速、中速、慢速冲刷三个阶段。随着致密层厚度的增加,对PS-PVD热障涂层抗冲刷性能的提升愈加明显。当致密层厚度为5μm时,对PS-PVD热障涂层抗冲刷性能无明显影响;当致密层厚度为10μm时,PS-PVD热障涂层抗冲刷性能提高了约30%;当致密层厚度为20μm时,PS-PVD热障涂层抗冲刷性能约提高了4倍。 相似文献
37.
38.
木地板种类繁多,其中实木复合地板是应用最为广泛、发展前景最好的品种之一。现阶段人们非常注重地板的材质和环保性能,却往往忽视地板与家居整体环境的协调,导致装修后整体效果不及预期。本文针对这种现象,结合实木地板的基本特性和室内设计的相关知识,总结了实木复合地板的组织设计原则及其与家具色彩的搭配方式,通过大量实例,生动展示了如何根据装饰装修风格来组织设计实木复合地板的颜色、纹样和功能,从而使家具陈设、墙面装饰、顶棚设计以及地面的铺装布局,在三维立体空间内实现多元有机互动,营造协调、宁静,并富有文化底蕴的室内环境氛围。 相似文献
39.
Zr doped ZnO nanoparticles are prepared by the sol-gel method with post-annealing. X-ray diffraction results show that all samples are the typical hexagonal wurtzite structure without any other new phase, as well as the Zr atoms have successfully entered into the ZnO lattices instead of forming other lattices. Magnetic measurements indicate that all the doping samples show room temperature ferromagnetism and the pure ZnO is paramagneism. The results of Raman and X-ray photoelectron spectroscopy indicate that there are a lot of oxygen vacancies in the samples by doping element of Zr. It is considered that the observed ferromagnetism is related to the doping induced oxygen vacancies. 相似文献
40.
聚异丁烯(PIB)具有优异的耐介质性能,作为化工添加剂被广泛应用于各种化工材料,将聚异丁烯应用于胶黏剂及密封胶可有效稳定黏度,降低黏温性;同时促进粘接,提高耐介质性能,增加低温下的柔韧性。研究了4种不同的聚异丁烯在单组分室温硫化硅橡胶(RTV-1)中的应用。通过在RTV-1中添加不同相对分子质量的PIB,重点考查PIB对于RTV-1拉伸强度、伸长率及耐介质老化性能的影响。结果发现,添加PIB所制得的RTV-1拉伸强度可达2MPa,伸长率370%左右,同时耐机油、耐水性、耐热氧老化性能优异。 相似文献