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1.
本文从理论上探讨了用机械振动分析法对康明斯发动机的燃烧状况进行监测时,应出现的振动信号的时域、频域波形的情况,并以此为指导在实验中确定了振动的最佳测点位置。  相似文献   
2.
The history of the development of a system for handling radwastes is presented in the context of the formulation of present Russian legislation pertaining to the use of atomic energy before the adoption of the Federal law in 2011. The deficiencies of the present system are noted, and a brief commentary is given on the most significant norms of the new law and the expected difficulties of its implementation.  相似文献   
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We evaluated the Medical Information System (MedISys) as an early-warning system for the detection of food- and feed-borne hazards. Nine hazards were selected in the period from January 2007 to March 2009 from the Rapid Alert System for Food and Feed (RASFF) and traced back on MedISys and ProMED-mail. In addition, from January to March 2009, food- and feed-borne (re-)emerging hazards were monitored on MedISys and traced back on ProMED-mail and RASFF. MedISys has demonstrated to be an effective early-warning system for food- and feed-borne hazards. However, further customization is required to improve its sensitivity, in particular by increasing the number of multi-lingual categories related to food and feed items. MedISys tended to detect food- and feed-borne hazards earlier and more frequently than ProMED-mail, but the information from both systems was often complementary.  相似文献   
4.
Water quality changes associated with the passage of aerobic reverse osmosis (RO) treated recycled water through a deep anaerobic pyritic aquifer system was evaluated in sediment-filled laboratory columns as part of a managed aquifer recharge (MAR) strategy. The fate of nine recycled water trace organic compounds along with potential negative water quality changes such as the release of metal(loid)s were investigated in large-scale columns over a period of 12 months.The anaerobic geochemical conditions provided a suitable environment for denitrification, and rapid (half-life <1-25 days) degradation of the endocrine disrupting compounds (bisphenol A, 17β-estradiol, 17α-ethynylestradiol), and iodipamide. However, pharmaceuticals (carbamazepine and oxazepam), disinfection by-products (N-nitrosodimethylamine, N-nitrosomorpholine) and iohexol did not degrade rapidly (half-life > 100 days).High retardation coefficients (R) determined for many of the trace organics (R 13 to 67) would increase aquifer residence time and be beneficial for many of the slow degrading compounds. However, for the trace organics with low R values (1.1-2.6) and slow degradation rates (half-life > 100 days), such as N-nitrosodimethylamine, N-nitrosomorpholine and iohexol, substantial biodegradation during aquifer passage may not occur and additional investigations are required.Only minor transient increases in some metal(loid) concentrations were observed, as a result of either pyrite oxidation, mineral dissolution or pH induced metal desorption, followed by metal re-sorption downgradient in the oxygen depleted zone.  相似文献   
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The author, a clinical psychologist, sustained a serious head injury in 1977 when research on the rehabilitation of the head injured was in its early stages and advocacy/support organizations did not exist. Despite the total unavailability of formal rehabilitation and therapy, the author, with the help of his family, was eventually able to return to professional practice and attain a reasonable quality of life. In this account, the author describes his journey toward recovery and the ways in which, 12 years postinjury, he copes with the impairments that remain. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
6.
The use of the Chernobyl experience in emergency data management is presented. Information technologies for the generalization of practical experience in the protection of the population after the Chernobyl accident are described. The two main components of this work are the development of the administrative information system (AIS) and the creation of the central data bank. The current state of the AIS, the data bank and the bank of models is described. Data accumulated and models are used to estimate the consequences of radiation accidents and to provide different types of prognosis. Experience of accumulated analysis data allows special software to be developed for large-scale simulation of radiation consequences of major radiation accidents and to organize practical exercises. Some examples of such activity are presented.  相似文献   
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The leaching of chalcopyrite from several Australian chalcopyrite concentrates by the reaction CuFeS2 + 4 Fe(III) + Cu(II) + 5 Fe(II) + 2 S0 obeyed parabolic kinetics in acidified nitrate solution between 25 and 40°C. The chalcopyrite reactivity was dependent on the mineral composition of the concentrate: the presence of pyrite accelerated the reaction markedly, but sphalerite and bismuthinite slowed it slightly. Galvanic interaction between minerals cannot account for this change: instead, the associated minerals must influence the rate determining diffusion of the lattice elements within the chalcopyrite crystal.  相似文献   
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智能变电站的无功控制需要实现实时就地平衡。传统变电站通常配置电容器组进行无功补偿,而随柔性交流输电技术的发展,动态无功补偿装置逐步应用于智能变电站无功补偿中,但很少有考虑两者的协调配置。针对以上情况,提出电容器组与静止无功补偿器(static var compensator, SVC)协调配合进行智能变电站的无功优化配置。在原最优覆盖思想仅考虑电容器的等容分组配置的基础上,增加SVC进行组合配置,在分析等容分组与几种典型不等容分组情况后,建立统一的无功失配面积最小及投资成本最优的多目标优化数学模型,并转换为年损耗最小的单一目标函数作为变电站无功配置的评价函数,用遗传算法进行寻优,获得SVC与等容及不等容分组的电容器组优化配置方案,进行对比,得到最优方案。最后采用某智能变电站无功负荷数据验证了该配置方法的有效性及实用性。  相似文献   
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