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本文围绕褐煤资源综合开发利用的问题进行了探讨;对褐煤煤质的特殊性进行了分析;对国内外褐煤提质加工技术进行了分类,简要说明了各类工艺的工作原理和技术特点;重点分析了国内外褐煤干燥热解技术的研究进展和工业应用情况,对工业化示范装置出现的问题进行了评价和总结;分析了制约褐煤发展的主要因素,并指出了未来产业发展的方向和重点. 相似文献
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列举了某公司尼龙生产线己二酸装置氧化反应器搅拌在多年运行中常见的损坏形式.分析了原因,提高了对氧化反应器搅拌的重视程度,及时对其采取预防措施.这些举措延长了搅拌器的使用寿命,保证了尼龙六六盐生产线的平稳运行,减少了生产成本,提高了经济效益. 相似文献
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<正>2010年1月16日—17日,公司召开了2010年度工作会议。会议认真回顾总结了2009年的主要工作,分析了当前的形势和机遇,部署了2010年的工作任务。会上,公司董事长蒋明作了重要讲话,总经理毛绍融作了行政工作报告,党委副书记陈百河作了党委工作报告,副总 相似文献
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文中详细介绍了几中丁二烯的生产工艺并进行了比较,总结出了它们的特点。对各地区丁二烯的生产能力以及消费状况进行了分析,并探究了丁二烯的新用途。 相似文献
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The fatigue behaviours were evaluated on a novel zirconia dental restoration known as self-glazed zirconia (SG), prepared by a precision additive 3D gel deposition approach, compared with a conventional zirconia (CZ) restoration, shaped by CNC milling of zirconia blanks made by cold isostatic pressing. Eight fixed partial dentures made by each method were subjected to fracture test, without or with the application of 5-million fatigue cycles, respectively. The processing defects, grain size, and t–m phase transformation were examined by SEM and XRD. The results revealed that the fracture force of the SG restorations was higher than that of the CZ restorations in both cases, which ascribed to the fact that more voids and larger grains in the conventional versus in the SG restorations. The t–m phase transformation was observed only on the fracture surfaces of both materials subjected to fatigue test. Both zirconia restorations meet the clinical requirement. 相似文献
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介绍了水热合成氧化锆的发展历程以及水热法制备氧化锆的特点和发展趋势。水热合成是一种合成氧化锆的重要方法,自发明以来就是该领域的研究热点。同时,介绍了氧化锆在陶瓷增韧、催化剂及载体、离子导电和生物等方面的应用。由于氧化锆的优异性质,其应用范围将越来越广阔。 相似文献
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在电熔单斜氧化锆原料中添加不同数量的CaO稳定剂,制备部分稳定氧化锆,研究CaO加入量和稳定相数量的关系.在制备的CaO部分稳定氧化锆中添加纳米氧化锆粉体,经过造粒、200 MPa压力成型、干燥、1650 ℃×2 h烧成制得试样.测试试样的物理性能、分析矿物相组成、观察显微结构,研究纳米氧化锆粉体添加量对试样性能的影响.研究结果表明:2Ca-PSZ、3Ca-PSZ、4Ca-PSZ试样中,4Ca-PSZ试样稳定化程度最高;3Ca-PSZ试样显气孔率小,体积密度较大,耐压强度高.在3Ca-PSZ试样中加入纳米氧化锆粉体,随着加入量的增加,试样的显气孔率下降、烧成收缩率增加、耐压强度提高.其中纳米氧化锆粉体添加比例为8wt%时,试样气孔率为9.4%,体积密度为5.08 g/cm3,抗压强度达到381 MPa.与3Ca-PSZ试样相比,气孔率下降40%,体积密度提高5%,耐压强度提高70%. 相似文献
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Daniel Glymond Michael J. Vick Finn Giuliani Luc J. Vandeperre 《Journal of the American Ceramic Society》2017,100(4):1570-1577
Reactive sintering of zircon and alumina and zirconia additions to mullite are well‐established methods for improving the poor fracture toughness of mullite. While it is clear that transformation toughening is responsible for the improved toughness by addition of partially stabilized zirconia, it is not clear why adding unstabilized zirconia increases the toughness although microcracking and crack deflection have been suggested. Therefore, the fracture toughness of a mullite composite with 20 vol% unstabilized zirconia and a monolithic mullite were investigated at ambient conditions and at temperatures up to 1225°C. It was found that monoclinic zirconia increases the toughness at ambient conditions from the monolithic mullite value of 1.9 to 3.9 MPa·m1/2. The toughness of the composite with zirconia remains relatively constant from ambient to 600°C but then decreases rapidly. The mechanism for the toughness enhancement as well as the reason for its variation with temperature are explained using changes in residual stress state as deduced using the sphere in shell model from the measured thermal expansion behavior. 相似文献
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介绍了氧化锆的性质、制备方法及国内外研究现状,概述了掺杂氧化锆的研究进展,并对氧化锆及掺杂氧化锆的发展方向进行了分析和讨论。 相似文献
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Zhiyong Wang Mohammed A. Al-Daous Elizabeth R. Kiesel Fan Li Andreas Stein 《Microporous and mesoporous materials》2009,120(3):351-358
Zeolite NaY nanocrystals (20−50 nm) were hydrothermally grown on polyelectrolyte-coated three-dimensionally ordered macroporous (3DOM) activated zirconia. The zeolite nanocrystallites uniformly coated the macropore walls of 3DOM sulfated zirconia, but sulfate groups were lost during the hydrothermal reaction. 3DOM tungstated zirconia was found to be more stable in the strong basic environment of the zeolite precursor solution. Further, ion-exchange of zeolite NaY with ruthenium followed by hydrogen-reduction formed a composite of RuNaY and 3DOM activated zirconia. The presence of ruthenium was confirmed by X-ray photoelectron spectroscopy and the external shape of zeolite nanoparticles was maintained after ion-exchange, but the zeolite lattice fringes could not be observed by transmission electron microscopy after incorporation of reduced ruthenium. Although the catalytic activity of the materials has not yet been tested, these hierarchical nano- and microstructures bring multiple catalyst components (modified zeolite Y, a typical Fischer–Tropsch catalyst, and activated zirconia, an isomerization catalyst) together in intimate contact for potential multi-reaction processes. 相似文献
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Shaobin Wang K Murata T Hayakawa S Hamakawa K Suzuki 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2001,76(3):265-272
The oxidative dehydrogenations of ethane and propane were investigated over a series of zirconia and nickel‐oxide supported on zirconia catalysts. It was found that zirconia, sulfated zirconia as well as NiO‐based zirconia catalysts showed high catalytic activities for oxidative dehydrogenation of ethane and propane. However, conversion and selectivity differed depending on the nature of the catalysts. Zirconia, sulfated zirconia (SZ) and their supported NiO catalysts showed high ethane conversions but lesser selectivities to olefins while NiO/Li2ZrO3 exhibited high selectivities to ethylene and propylene. Addition of an LiCl promoter in the NiO/SZ catalyst increased the catalytic activity and olefin selectivity, thus resulting in a higher olefin yield. In the oxidative dehydrogenations of ethane and propane NiO–LiCl/SZ exhibited 79% ethylene selectivity at 93% ethane conversion at 650 °C and 52% selectivity to propylene at 20% propane conversion at 600 °C, respectively. Characterization showed that the physico‐chemical properties of the catalysts determine the catalytic activity and selectivity. © 2001 Society of Chemical Industry 相似文献