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1.
对立方型状态方程的分析和改进及对超临界工质的计算 总被引:1,自引:0,他引:1
1对现有立方型状态方程特性的分析研究与改进现有的立方型状态方程无论是SRK方程还是PR方程都有其固定的适用范围,井且与偏心因子有关。另外,这两个方程的引力项中均引人温度函数叫Tr;叫。但是,偏心因子。不反映强极性物质的特点,这对计算强极性质起不到应有的作用,还有这两个方程中的常数a和b,其系数几和成都是定值,特别是门数值偏大,对计算液体密度是不利的,甚至有时还出现摩尔体积比6值还小,即V<6,这是很不合理的。在超临界流体区流体密度也比较大,相当于液体密度,故这种状态方程也不适用,基于这些不足之处,本文作者… 相似文献
2.
In this study, cultural, economic as well as certain crucial demographic factors are considered as the determinants for projecting the average family size in rural India. We use the Analytic Hierarchy Process to analyze influences of the factors which enter implicitly in a rural couple's decision‐making to determine the number of children they want to have as time goes by. We did not attempt to make distinctions among the regional differences in rural India. The outcome projected in our analysis compares favorably with the results of other demographic studies. 相似文献
3.
委托-代理关系下的企业筹资决策模型 总被引:2,自引:0,他引:2
本文建立了在委托代理关系下的企业筹资决策的数学模型 .模型分析表明 ,股东在设立经理激励合同时 ,将经理报酬与权益资本利润率联系起来 ,能够激励经理选择负债经营 ,但经理选择的最优资本结构可能会偏离股东效用最大化的资本结构 . 相似文献
4.
Henk Flap Bert Bulder Beate V#xD;lker 《Computational & Mathematical Organization Theory》1998,4(2):109-147
Intra-organizational network research had its first heyday during the empirical revolution in social sciences before World War II when it discovered the informal group within the formal organization. These studies comment on the classic sociological idea of bureaucracy being the optimal organization. Later relational interest within organizational studies gave way to comparative studies on the quantifiable formal features of organizations. There has been a resurgence in intra-organizational networks studies recently as the conviction grows that they are critical to organizational and individual performance. Along with methodological improvements, the theoretical emphasis has shifted from networks as a constraining force to a conceptualization that sees them as providing opportunities and finally, as social capital. Because of this shift it has become necessary not only to explain the differences between networks but also their outcomes, that is, their performance. It also implies that internal and external networks should no longer be treated separately.Research on differences between intra-organizational networks centers on the influence of the formal organization, organizational demography, technology and environment. Studies on outcomes deal with diffusion and adaptation of innovation; the utilization of human capital; recruitment, absenteeism and turnover; work stress and job satisfaction; equity; power; information efficiency; collective decision making; mobilization for and outcomes of conflicts; social control; profit and survival of firms and individual performance.Of all the difficulties that are associated with intra-organizational network research, problems of access to organizations and incomparability of research findings seem to be the most serious. Nevertheless, future research should concentrate on mechanisms that make networks productive, while taking into account the difficulties of measuring performance within organizations, such as the performance paradox and the halo-effect. 相似文献
5.
Three hypotheses about the effects of different informal social network structures on gossip behavior are developed and tested. Gossip is defined as a conversation about a third person who is not participating in the conversation. Having analyzed the costs and benefits of gossip, we prefer the coalition hypothesis.~It states that gossip will flourish in social networks that have a relatively large number of coalition triads, that is ego and alter having a good relationship amongst themselves and both having a bad relationship with tertius, the object of gossip. Two rivalling hypotheses are developed. The constraint hypothesis predicts that the inclination towards gossip is greater, the larger the number of structural holes in the personal network of the gossipmonger.~The closure hypothesis predicts that more gossip will be found in networks with a large number of closed triads, that is where both gossipmonger and listener have a good relationship with the absent third person. The hypotheses are tested using a newly developed instrument to measure gossip behavior and network data from six work organizations and six school classes. The data support the coalition hypothesis and do not support the two rivalling hypotheses. 相似文献
6.
基于语言评价信息的知识资本要素识别方法 总被引:2,自引:0,他引:2
知识资本是组织创造价值和获取竞争优势的关键资源, 其要素通常具有复杂的关联性, 如何识别知识资本的核心要素、原因要素和结果要素,对于组织进行知识资本管理具有重要意义.本文在构建了知识资本要素识别体系的基础上,借鉴决策试验和评价实验室报告的思想提出了一种基于语言评价信息的知识资本要素识别方法,通过处理和集结专家针对知识资本要素关联给出的语言评价信息,对知识资本要素进行排序与归类.最后通过一个实例分析说明了该方法的应用, 并说明了如何根据识别结果制定相应的策略以便进行知识资本的投资和控制. 相似文献
7.
Network science has been widely applied in theoretical and empirical studies of global value chain (GVC), and many related articles have emerged, forming many more mature and complete analytical frameworks. Among them, the GVC accounting method based on complex network theory is different from the mainstream economics in both research angle and content. In this paper, we build up global industrial value chain network (GIVCN) models based on World Input–Output Database, introduce the theoretical framework of Social Capital, and define the network-based indicators with economic meanings. Second, we follow the econometric framework to analyze the hypothesis and test whether it is true. Finally, we study how the three types of capital constituted by these indicators interact with each other, and discuss their impact on the social capital (economic development level, i.e., GDP). The results prove that the structural capital (industrial status) has a positive impact on the social capital; the relational capital (industrial correlation) has a positive impact on both social capital and structural capital; the cognitive capital (industrial structure) has a small impact on the social capital, structural capital, and relational capital. 相似文献
8.
The paper demonstrates conceptual parallels and relationships between intellectual capital measurement methods and the evaluation of quality in clinical laboratories in the Slovak Republic. It explores further the contextual links of those parallels with the tangibility (or intangibility) of quality indicators of laboratory diagnostics. It also highlights the problems which laboratory staff in Slovakia are confronted with. Presented at the conference Quality in the Spotlight, March 2007, Antwerp, Belgium. 相似文献
9.
三种中高温热泵工质循环性能实验研究 总被引:1,自引:0,他引:1
采用改进型的循环性能对比实验评价研究方法,在水-水蒸汽压缩式热泵实验台上,对理论循环性能优良、样品可得的混合工质M3、M4和纯质HFC245fa,在冷凝温度90~95℃、蒸发温度40~65℃的工况范围内进行了循环性能对比实验研究.研究结果表明,与在冷凝温度90~100℃工况范围内实验性能较优的纯质HFC245fa相比,M3和M4的制热量和COP均明显高于HFC245fa,排温比HFC245fa高10℃左右,综合性能优于HFC245fa;两种混合工质中,M3的环境特性和循环性能最优. 相似文献
10.
S. A. Agamy M. Y. Khalil M. Y. Hamza W. A. Abou-Taleb 《Isotopes in environmental and health studies》2013,49(6):287-291
Microstructure defects play a very important role in the swelling of irradiated stainless steel. This work is a parametric study of the effects of microstructural defects on the swelling of ion-irradiated steel. For simplicity, vacancy loop effects were neglected. Cold working was found to play a complicated role in the swelling behavior. On one hand, it increase the bias to interstitial absorption due to the increase in dislocation density. On the other hand, it decreases the total flux of point defects to voids by the decrease of the point defect concentrations. Grain size has also a strong effect on swelling. It was found that large gain sizes produces higher swelling and vise versa, i.e. the larger the surface of grain boundaries the less the irradiation-produced swelling. Similar effects were found for precipitates. 相似文献