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91.
析企业高层管理者培训的实效性问题   总被引:1,自引:0,他引:1  
分析了影响企业高层管理者培训实效性的原因,并指出要提高企业高层管理者培训的实效性,必须重视企业高层管理者培训的特殊性,着力解决培训的激励机制问题,加强培训需求调研,建设高素质的培训师资队伍。  相似文献   
92.
天然沉积物中存在主要由粉质土或粉细砂土含黏性土构成的中间土.通过系统的室内和现场试验,明确了天然海相黏性土和天然海相中间土之间性质的不同.天然中间土天然含水量与液限之比几乎与软质天然海相黏土相似,但是前者相对后者的灵敏度和现场强度更高.粒度分布对锥尖阻力有显著的影响.由于高灵敏度和相对大的渗透性,试样的扰动更加显著地影响了天然海相中间土的力学参数.无侧限抗压强度试验,显著低估了天然海相中间土的强度,而简易三轴固结再压缩剪切试验相对无侧限抗压强度qo试验有显著的改善。  相似文献   
93.
对接于公共联结点(PCC)的并联负载,如果对各负载只按其各自消耗的无功电流进行补偿或收费而不考虑负载之间的相互补偿作用是不合理的。该文提出了一个合理的确定各负载对PCC无功功率的贡献的方法:如果某一负载的无功电流在PCC提供的无功电流上的投影为正,则这一负载对PCC无功电流的贡献与其在PCC无功电流上的投影大小成正比;如果投影为负,则这一负载对PCC无功电流没有贡献,其无功电流只在负载间流动。各负载按无功电流贡献确定对总无功费用分担的比例。算例结果表明:文中提出的方法是经济合理的。它不仅适用于传统的正弦电路,而且适用于非正弦及不对称电路,对无功功率补偿、管理和收费具有实用意义。  相似文献   
94.
A mechanism for proof-of-reputation consensus for blockchain validator nodes is proposed to deal with existing blockchain consensus mechanism's lack of evaluation of validator node's reputation and the inability to effectively prevent Byzantine behaviors. First, an interactive indicator is designed for validator nodes to represent their contribution in the blockchain network, which will be used as the reputation benchmark of validator nodes. Second, another reliability indicator is designed for validator nodes from the aspects of online time and the number of valid blocks, which will be used as the weight of the reputation improvement of validator nodes. Finally, the reputation of validator nodes of the current round is comprehensively calculated, and a set of producing validators of the current round is selected based on the reputation ranking. Experimental results show that the proof of reputation consensus mechanism has certain advantages in dealing with malicious and lazy behaviors, and that it can also reduce the impact of capital and energy consumption on the blockchain consensus mechanism while ensuring the validity of the credit evaluation.  相似文献   
95.
阐述了影响企业效益因素重要程度的 D 值分析法.对企业获利能力建立了多元线性回归分析模型,尝试性地作了评价方法的阐述.  相似文献   
96.
Some functional lanthanide metal complexes, such as acetylacetonato complexes, ethylenediaminetetraacetato complexes, were successfully applied for diagnostic technique. The authors are interested in investigating the structure and bonding in lanthanide and actinide metal complexes using 166Er, t55Gd, and 237Np Mtissbauer spectroscopies in connection with single-crystal and/or powder X-ray diffraction, making clear the differences on their structures as well as the differences in the participation of 4f and 5f orbitals in the chemical bonds. In this article, the crystal structures of two novel Gd(Ⅲ) acetylacetonato complexes, Gd(pta)3 · 2H2O (pta = 1,1,1 -trifluoro-5,5-dimethy 1-2,4-hexanedione) and Gd(bfa)3 · 2H2O (bfa = 1, 1, 1 -trifluoro-4-phenyl-2-4-butanedione) were reported. Though both of them were dihydrate and had distorted square antiprismatical structure, Gd(pta)3 · 2H2O crystallizes in the P 2 1/n (#14) monoclinic space group and its lattice parameters are a = 1.4141(6) nm, b = 1.0708(3) nm, c =2.2344(4) nm, β =952.4(2)°, and Gd(bfa)3· 2H2O crystallizes in P 212121 orthorhombic space group and its lattice parameters were a = 1.322 (1) nm, b = 2.295 (1) nm, c = 1. 0786(8) nm. In the meantime, the authors had finished a systematic investigation on the ^155Gd Mossbauer isomer shift (δ) of various Gd(Ⅲ) metal complexes having a different coordination number (C.N.) and different ratios coordinating oxygen to nitrogen. A tendency for the 6 value to decrease with an increase in the C.N, and the number of the nitrogen atom coordinating to Gd was confirmed. This indicated that the Gd-O and/or Gd-N bond in the investigated Gd(Ⅲ) metal complexes had a small covalent contribution, which was possible to be deduced from the O and/or N atoms of the lisands donating electrons to 6s, 5d, and 4f orbitals of Gd.  相似文献   
97.
Five questions prompted by the articles in the American Psychologist special issue on leadership (January 2007, Vol. 62, No. 1., see records 2006-23492-001, 2006-23492-002, 2006-23492-003, 2006-23492-004, 2006-23492-005, and 2006-23492-006) suggest some new directions for leadership research: (1) Not do leaders make a difference, but under what conditions does leadership matter? (2) Not what are the traits of leaders, but how do leaders' personal attributes interact with situational properties to shape outcomes? (3) Not do there exist common dimensions on which all leaders can be arrayed, but are good and poor leadership qualitatively different phenomena? (4) Not how do leaders and followers differ, but how can leadership models be reformulated so they treat all system members as both leaders and followers? (5) Not what should be taught in leadership courses, but how can leaders be helped to learn? (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
98.
The lattice contribution to the thermal conductivity (κph) in La0.80Ca0.20 MnO3 manganites is discussed within the Debye-type relaxation rate approximation in terms of the acoustic phonon frequency and relaxation time. The theory is formulated when heat transfer is limited by the scattering of phonons from defects, grain boundaries, charge carriers, and phonons. The lattice thermal conductivity dominates in La–Ca–MnO manganites and is an artifact of strong phonon-impurity and -phonon scattering mechanisms in the ferromagnetic metallic state. The electronic contribution to the thermal conductivity (κe) is estimated following the Wiedemann–Franz law. This estimate sets an upper bound on κe, and in the vicinity of the Curie temperature (240 K) κe is about 1% of total heat transfer of manganites. Another important contribution in the metallic phase should come from spin waves (κm). It is noticed that κm increases with a T2 dependence on the temperature. These channels for heat transfer are algebraically added and κtot develops a broad peak at about 55 K, before falling off at lower temperatures. The behavior of the thermal conductivity in manganites is determined by competition among the several operating scattering mechanisms for the heat carriers and a balance between electron, magnon, and phonon contributions. The numerical analysis of heat transfer in the ferromagnetic metallic phase of manganites shows similar results as those revealed from experiments.   相似文献   
99.
许民利  李展 《控制与决策》2013,28(11):1614-1622

为了探讨风险态度、现实约束对决策行为的影响, 建立了具有预算约束、损失约束、需求依赖于价格、基于条件风险价值(CVaR) 准则的价格-订单量决策模型, 并给出了模型最优解与约束条件有效阀值求解方法. 研究结果表明, 条件风险价值对损失约束比对预算约束的敏感程度高, 而不同约束的高敏感区域位置不同; 风险规避程度越高, CVaR 对约束值的弹性系数越低; 预算约束值的提高降低了边际贡献率, 风险规避程度越高, 降低幅度越大.

  相似文献   
100.
Temperature has great influence on the stacking fault energy (SFE). Both SFE and dr0/ d T for Fe-based alloys containing substitutional or interstitial atoms increase with increasing tempera-ture. Based on the thermodynamic model of SFE, the equation dr0/dT=drcn/dT+drseg/dT+drMG/dT and thoseexpressions for three items involved are established. The calculated dr0/dT is generally consistent with the experimental. The influence of chemical free energy on the temperature dependence of SFE is almost constant, and is obviously stronger than that of magnetic and segregation contributions. The magnetic transition and the segregation of alloying elements at stacking faults cause a decrease in SFE of the alloys when temperature increases; that is, drMG/dT<0 and dyseg/dT<0. Meanwhile, such an influence decreases with increasing temperature, except for the drseg/d 7 of Fe-Mn-Si alloys. With these results, the experimenal phenomena that the SFE of Fe-based alloys is not zero at the thermo-dynamically equilibrated tem  相似文献   
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