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71.
72.
简述土壤源热泵基本工作原理、埋管形式、优势及实用性,工程实例介绍北京九华山庄二期土壤热泵系统的设计、施工、调试情况,阐述了选择复合式系统的理由。 相似文献
73.
Yu. S. Gorbunov A. G. Ageev R. V. Vasil’eva B. M. Korol’kov 《Power Technology and Engineering (formerly Hydrotechnical Construction)》2007,41(3):166-170
A system for the direct measurement of steam flow in steam lines after a steam generator, which utilizes a special design
of pneumometric tubes and a computing unit that accounts for variation in steam pressure, has been developed to improve the
quality of water-level regulation in the steam generators of VVéR-1000 power-generating units in the stationary and transitional
modes. The advantage of the pneumometric tubes consists in their structural simplicity, high erosion resistance, and absence
of irrevocable losses during measurement of steam flow. A similar measurement system is used at foreign NPP. The measurement
system in question has been placed in experimental service at the No. 3 unit of the Balakovo NPP, and has demonstrated its
worthiness. This measurement system can also be used to determine steam flow in the steam lines of NPP units with VVéR-1000
and VVéR-440 reactors, and PBMK-1000 power-generating units.
__________
Translated from élektricheskie Stantsii, No. 3, March 2007, pp. 23–26. 相似文献
74.
Reviews the book, Qualité de vie et drogues. Place aux jeunes (1986). In this volume, the author shares his initiatives in the plan of therapeutic and preventive intervention. This book discusses drug use and quality of life in young people. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
75.
提高连续油管使用寿命的方法 总被引:2,自引:1,他引:1
从采用软件跟踪疲劳寿命 ,截断法 ,变径连续油管 ,反转使用连续油管 ,防止连续油管损伤 ,合理配置设备 6个方面讨论了控制管串疲劳 ,提高连续油管使用寿命的方法 ,并得出结论 :控制管串疲劳的方法中 ,最有效的方法是实际作业截断法。指出要尽量减少连续油管在带内压下工作 ,也要研究开发降阻性能好的工作液 ,以延长连续油管使用寿命、降低作业风险。 相似文献
76.
Many new speciality polymers have been developed in the last few years. In this paper polymeric stabilizers (antioxidants, flame retardants and ultraviolet stabilizers) will be discussed. Polymeric antioxidants of the hindered-phenol type, copolymers of 2,6-ditertiarybutyl-4-vinyl(or isopropenyl)phenol with styrene, methyl methacrylate, or more importantly butadiene or isoprene have been prepared; hydrogenation of the latter copolymers gave copolymers of the two polymerizable phenolic antioxidants with ethylene or ethylene/propylene. The polymeric antioxidants have been blended with diene polymers and selected polyolefins and have improved the long-term oxidative stability of these polymers. Polymeric flame retardants have been prepared by copolymerizing styrene and/or acrylonitrile with acrylates and methacrylates of aliphatic bromine-containing alcohols or bromine-containing phenols. Polymers with polymer-bound flame retardants have a higher limiting oxygen index compared with the original polymer. A new class of polymerizable ultraviolet stabilizers has also been developed; these stabilizers are styryl, α-methylstyryl, acryloyl and methacryloyl derivatives of 2(2-hydroxyphenyl)2H-benzotriazoles. These monomers have been copolymerized with styrene, acrylates and methacrylates. 2(2-Hydroxyphenyl)2H-benzotriazoles substituted in the 4 position of the benzotriazole ring with hydroxyl, acetoxy or carboxyl groups suitable for incorporation into polyesters, polycarbonates, polyamides and epoxy resins have also been synthesized. All 2(2-hydroxyphenyl)2H-benzotriazole ultraviolet absorbers and the polymers into which they are incorporated have high light absorbency with γmax between 330 and 350 nm and extinction coefficients in some cases as high as 4.5 × 104 1 mol?1 cm?1. 相似文献
77.
H.-P. WiendahlM. Hegenscheidt 《CIRP Annals》2002,51(1):15-19
Tuning the performance parameters of all stations of interlinked manufacturing and assembly systems to ensure the planned capacity is a major challenge. The application of system simulation for this task is little common, particularly in SMEs. A suitable tool for quickly assessing the specific influence of a standalone station on the entire system performance has been developed on the basis of the characteristic curve theory. The applied methodology and the results obtained are presented in this paper. 相似文献
78.
79.
Wide variability exists with respect to how breast cancer survivors respond to common psychological and psychosocial challenges of their disease, ranging from posttraumatic stress disorder to posttraumatic growth. This cross-sectional study examined contextual, disease-related, and intraindividual predictors of posttraumatic growth in 224 randomly selected breast cancer survivors. A series of hierarchical regression analyses found that age at diagnosis, marital status, employment, education, perceived intensity of disease, and active coping accounted for 34%, 35%, and 28% of the variance in growth in relationships with others, new possibilities, and appreciation for life. These findings suggest that a more comprehensive model of growth will be helpful in understanding the various factors that play a role in breast cancer survivors' perception of psychological and psychosocial growth. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
80.
通过对真丝绸整个产品生命过程的分析,对其进行了生命周期评价,说明了丝绸与其产地环境之间的联系和影响,尝试寻求两者之间的和谐关系,提出了清洁生产工艺的规划和各种行之有效的对策和措施,尝试了对环境友好的丝绸印染工艺的生态设计。 相似文献