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欧洲各国采用的反刍动物能量评定新体系
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作者 杨在宾 李凤双 《饲料世界》 1991年第1期45-48,39,共5页
关键词 反刍动物 能量评定 体系 欧州
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高钢级管线钢的延性断裂:CVN和DWTT动态冲击试样应力状态和能量的研究 被引量:1
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作者 孙宏 栾涛 +1 位作者 宗秋丽 郑青昊(编译) 《焊管》 2020年第10期56-60,64,共6页
针对高强韧钢的止裂性能,讨论了可用的管道止裂预测技术的现象学基础和局限性,以及在更大塑性变形时如何修订和修正结构钢的韧性,以便更好地理解在这种情况下钢的延性断裂过程。通过进行GTN损伤模型和扩展有限元(XFEM)模型的数值分析,... 针对高强韧钢的止裂性能,讨论了可用的管道止裂预测技术的现象学基础和局限性,以及在更大塑性变形时如何修订和修正结构钢的韧性,以便更好地理解在这种情况下钢的延性断裂过程。通过进行GTN损伤模型和扩展有限元(XFEM)模型的数值分析,包括参数的校准和灵敏度分析,对采用三点弯曲加载方式的X80钢夏比冲击试样及DWTT试样进行了模拟。结果表明:两种模型在应力状态和能量方面的结果都很接近,说明两种方法都可以考虑用作所需分析的比对。GTN模型更具现象学性,而XFEM模型被证明更简单、更实用。此外,应力场和能量可以针对所研究的几何形状进行量化,并且此类分析表明了夏比和DWTT试样表征描述稳态延性断裂扩展和止裂所需能量的可能性和局限性。结果支持进一步研究相关管道完整性评定。 展开更多
关键词 输气管道 止裂 高钢级钢 损伤模型 能量评定
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用B—LA指标评定速滑运动员的无氧和有氧代谢能力
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作者 李双滨 牟秀荣 《哈尔滨体育学院学报》 1998年第3期70-73,共4页
通过对速度滑冰运动供能系统分析及短、长距离不同的供能要求,表明了要合理地安排各种负荷强度,必须科学地确定强度标准,提出利用B—LA指标和简易方法评定三种能量单位,为教练员、运动员科学安排负荷提供参考依据。
关键词 B—LA 能量系统评定 速滑运动员
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Could quantitative liver function tests gain wide acceptance among hepatologists? 被引量:7
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作者 Giovanni Tarantino 《World Journal of Gastroenterology》 SCIE CAS CSCD 2009年第28期3457-3461,共5页
It has been emphasized that the assessment of residual liver function is of paramount importance to determine the following: severity of acute or chronic liver diseases independent of etiology; long-term prognosis; s... It has been emphasized that the assessment of residual liver function is of paramount importance to determine the following: severity of acute or chronic liver diseases independent of etiology; long-term prognosis; step-bystep disease progression; surgical risk; and efficacy of antiviral treatment. The most frequently used tools are the galactose elimination capacity to asses hepatocyte cytosol activity, plasma clearance of indocyanine green to assess excretory function, and antipyrine clearance to estimate microsomal activity. However, a widely accepted liver test (not necessarily a laboratory one) to assess quantitative functional hepatic reserve still needs to be established, although there have been various proposals. Furthermore, who are the operators that should order these tests? Advances in analytic methods are expected to allow quantitative liver function tests to be used in clinical practice. 展开更多
关键词 Chronic diseases Fatty liver Hepatitis viral Liver cirrhosis Liver function tests Prognosis
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Regional Study on Economical Supporting Capacity of Land Resources in Shandong Province
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作者 Li Yujiang Chen Pei'an 《Chinese Journal of Population,Resources and Environment》 北大核心 2007年第1期68-73,共6页
Taking the land resources of 17 cities in Shandong Province as the basic data, the article studied on the economical supporting capacity of land resources in terms of the effect of land on economy. The author classifi... Taking the land resources of 17 cities in Shandong Province as the basic data, the article studied on the economical supporting capacity of land resources in terms of the effect of land on economy. The author classified 17 cities of Shandong Province into four types according to the economical supporting capacity of land resources by quantitatively estimating the evaluation indices of the total amount of land resources, the potential of urban and other nonagricultural land, and the integrated economical sup- porting capacity of land resources, etc. The author proposes the questions requiring further study at the end of this article. 展开更多
关键词 land resources economical supporting capacity quantitative estimation Shandong Province
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Quantitative Evaluation on Wetland Ecosystem Service Function in Chao Lake
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作者 唐晓先 高芮 《Agricultural Science & Technology》 CAS 2016年第11期2489-2492,2504,共5页
[Objective] The aim was to better reveal the type of ecosystem service function of wetlands in Chao Lake and provide references for protection and man- agement, restoration and rebuilding of local wetland ecosystem. [... [Objective] The aim was to better reveal the type of ecosystem service function of wetlands in Chao Lake and provide references for protection and man- agement, restoration and rebuilding of local wetland ecosystem. [Method] The val- ues of ecosystem function was estimated by market value method, opportunity cost approach, replacement cost method, shadow engineering approach, travel cost method, hedonic pricing method and contingent value method. [Result] With wetland ecosystem service function value totals 4.968 billion yuan, the value of eco-environ- ment regulation and maintenance was the highest, followed by the value of cultural and social function. The value of material production was the least. The values of sub-functions can be concluded by comparison of service function va}ue and pro- portions, as follows: flood mitigation 〉water purification 〉water conservation 〉 tourism&leisure〉material production〉scientific research and education〉water supply〉 biodiversity maintenance〉regulation on atmosphere constituents. [Conclusion] The re- search performed quantitative evaluations on ecosystem service function values of wetlands in Chao Lake and is of significance for specific development and protec- tion of local wetlands. 展开更多
关键词 Chao Lake Wetland ecosystem service function Quantitative evaluation
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Evaluation Method for Coordinated Development of Renewable Energy and Smart Grids
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作者 Dong Bo Wang Wei 《Electricity》 2012年第4期11-15,共5页
Modern power systems are typically characterized with renewable energies and smart grids.Their developments should be kept at a compatible pace with each other.According to the different structures of the power indust... Modern power systems are typically characterized with renewable energies and smart grids.Their developments should be kept at a compatible pace with each other.According to the different structures of the power industry,such as generation,transmission,distribution,consumption and dispatching,a comprehensive evaluation system for coordinated development of renewable energy and smart grid in"3 levels,4 sections,15 targets"is created.The index system of coordinated development is important to determine the priorities and key areas in smart grids and renewable energies.By the index system of coordinated development,this paper evaluates the status of renewable energy and grid development,and their degree of coordination in China.A quantitative evaluation method to determine the level of coordination between China's renewable energies and smart grids is developed.The total and component coordination levels in China are calculated by an analytic hierarchy process.In conclusion,the degree of coordination in transmission and dispatching is higher, but the extent of electricity consumption is lowest.Therefore,the consumption section should be the first to develop within China. 展开更多
关键词 renewable energy smart grid coordination index
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Emergy footprint evaluation of hydropower projects 被引量:7
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作者 WU JianHua HE ChengLong XU WeiLin 《Science China(Technological Sciences)》 SCIE EI CAS 2013年第9期2336-2342,共7页
In the past thirty years, various hydropower projects, some with a dam height of over 300 m, have been planned and constructed within China. It is inevitable that these will have sizable effects on the environment, an... In the past thirty years, various hydropower projects, some with a dam height of over 300 m, have been planned and constructed within China. It is inevitable that these will have sizable effects on the environment, and it is crucial therefore to reasonably evaluate and control adverse effects. In this paper, the transformities of various items for hydropower projects were systematically analyzed, and an emergy footprint model for the projects was developed based on ecological footprint analyses and emergy theory, so that it can quantitatively evaluate the effects on the environment, both positive and negative, resulting from the whole process of planning, constructing and operating the projects. As an example, the effects of a large-scale hydropower project, the 'LP project', were investigated. The results showed that the hydropower projects have strong positive effects on the environment and can even in the short term balance the emergy footprint appropriation resulting from the construction and operation of the hydropower projects. Finally, suggestions were presented for the design of hydropower projects. 展开更多
关键词 ecological footprint EMERGY emergy footprint model ENVIRONMENT hydropower project transformity
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