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81.
82.
蒲荣松 《中国水能及电气化》2017,(1)
坝基坝体渗水对大坝安全运行有不利影响。本文采用现场检查、水样试验、析出物试验、资料分析等手段,对碾压混凝土坝运行期渗水及其析出物对大坝的影响进行了较全面的分析,并提出了运行期需关注的问题。 相似文献
83.
由于市场、人力资源及成本的优势,跨过公司在我国的投资不断增加,我国已成为全球研发投资项目的最大积聚地。介绍了近几年跨国化工企业在我国投资的项目情况,新一轮的投资主要集中在长江三角洲地区。随着众多跨国公司的签约,催生了南京化学工业园区、上海化学工业区、泉州泉港石化工业区,惠州大亚湾石油化学工业区,同时也将一体化基地的理念带入中国。 相似文献
84.
增强聚氨酯硬泡塑料的冲击性能研究 总被引:3,自引:0,他引:3
本文研究了SiO2和纤维增强剂对于聚氨酯硬泡塑料冲击性能的增强效应.试验结果表明,加入SiO2并不能增强聚氨酯硬泡塑料冲击性能.然而以2.5% KH550偶联剂四氢呋喃溶液处理的玻璃纤维作为增强剂,能使聚氨酯硬泡塑料的冲击性能有显著的提高. 相似文献
85.
86.
Louise Therese Pick Eileen Harkin‐Jones Maria Jovita Oliveira Maria Clara Cramez 《应用聚合物科学杂志》2006,101(3):1963-1971
This article examines changes to the morphology of rotationally molded metallocene catalyzed linear low density polyethylene brought about by varying the cooling rate during processing. These changes in morphology lead to variations in the impact performance, which is reflected in the dynamic mechanical characteristics of the materials. Various analytical techniques are used in an attempt to explain the differences in impact behavior. Slow cooling is shown to result in high crystallinity, and in the formation of large spherulites, which in turn is detrimental to the impact performance of the material, particularly at low temperatures. The high crystallinity corresponds with a shift in the β transition of the material to a higher temperature, and is shown to result in a higher brittle–ductile transition. A case study was also carried out on samples from a finished part provided by an industrial molder, one section of which failed in a brittle manner when impact tested while the other failed in a ductile manner. Microscopy results showed that the brittle material had large spherulites at the inside surface, while the ductile material showed incipient degradation at this surface, which has previously been shown to be of benefit to impact strength in rotationally molded parts. Dynamic mechanical studies again showed a β transition at a higher temperature in the brittle samples. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 1963–1971, 2006 相似文献
87.
1993年化工系统完成总产值1796.3亿元,比上年增长7.3%。全年完成固定资产投资230多亿元,比上年增长19%。全年进出口总额达187亿美元,比上年增长16.1%。但化学工业发展速度低于全国工业的增长速度。 相似文献
88.
89.
Heinz Ludwig 《Desalination》2004,164(1):1-18
Ever since seawater desalination has been applied on an industrial scale, and particular in the countries of the Arabian Gulf, the application of desalination processes in dual-purpose facilities—water and power—as a hybrid configuration has been discussed in many feasibility investigations and also planning concepts. It is above all the combination of reverse osmosis with thermal processes that has found increasing interest with the aim of ensuring, as economically as possible, uniform water supplies under the specific, greatly varying load conditions in the Gulf countries. Such design concepts for hybrid configurations encompass straightforward structures with a low degree of coupling between membrane and thermal desalination processes, but range up to very complex configurations with strong interconnections on both the water side and thermally, as well as with several desalination processes connected in series or in parallel. Classical hybrid concepts in which the permeate from an RO desalination component is mixed with distillate from thermal desalination have already been implemented in Saudi Arabian dual-purpose plants, like Jeddah and Yanbu-Medina. Although hybrid systems of greater complexity have been addressed in many design studies and publications, up to now none has been brought to fruition. Coming into consideration asthe design basis for determining the capacity shares of the various desalination processes operated in a hybrid configuration are: arrangement of thermal cycle of the power plant component; water/power ratio of the dual-purpose seawater desalination and power plant; provision of undiminished water production of the desalination plant as electricity generation varies; provision of a specified drinking water quality with regard to composition and salt content; combination of all these aspects. Also gaining in importance are concerns of environmental pollution and sustainable development when selecting seawater desalination and power plant configurations, as well as their optimization when considering desalination and electricity generation as a whole. In the practical design of hybrid membrane and thermal systems, aspects come to light, though, that restrict linking of the two systems and joint utilization of facilities, as conceived in studies and conceptual design investigations. This applies both for common utilization of intakes and the use of heated up cooling water from thermal processes as a feed stream for the RO part of the desalination process. Additionally, requirements of drinking water composition, particularly chloride content, TDS and compliance with a specific residual content of boron, influence specifically the design of the membrane process part and its share in the total desalination capacity. Such practical aspects have greatly influenced the design and configuration of the Fujairah hybrid plant for which, from a total desalination capacity of 100 MIGD (454,600 m3/d), the share of 37.5 MIGD (170,500 m3/d) makes its seawater RO plant the biggest currently being constructed anywhere in the world. From the findings of the engineering of this plant and the idea that, by increasing interconnection between the two processes on the water side, it is possible to advance a hybrid configuration of this type with regard to cost optimization in the membrane installation, but also by joint utilization of the intake equipment, perspectives result for applied research efforts over the near and long terms, for example: long-term behavior of membranes at elevated temperatures; tendency for biofouling in membrane process with common utilization of cooling water and brine; influences of such interconnections on the overall availability of the facility. But also for the operation and maintenance organization of such large facilities, consequences can be foreseen for the future development of hybrid plants, particularly for operation management and organisation of the interplay of the different power plant and desalination systems, monitoring of SWRO membrane replacement and cleaning, as well as controlling water quality. 相似文献
90.
在经济全球化的国际大背景下,我国不仅要实施“引进来”的发展战略,更要着手“走出去”的发展战略。在实施“走出去”发展战略的过程中,为了保护我国境外资本在东道国的安全和利益,必须有一套健全的境外投资保险法律制度。而我国目前在这方面基本上是处于一种制度供给稀缺的状态,因此,我国有必要在对比分析他国相关制度的基础上,借鉴他国的先进制度经验,建立、健全我国的境外投资保险法律制度,以为我国“走出去”的发展战略提供坚固的“法制防火墙”。 相似文献