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991.
Jun-Woo ParkKazuki Yoshida Naoki TachikawaKaoru Dokko Masayoshi Watanabe 《Journal of power sources》2011,196(4):2264-2268
The physicochemical and electrochemical properties of the binary ionic liquid (IL), lithium bis(trifluoromethylsulfonyl)amide (LiTFSA) dissolved in N,N-diethyl-N-methyl-N-(2-methoxyethyl)ammonium bis(trifluoromethylsulfonyl)amide (DEMETFSA), were investigated. The ionic conductivity of the binary IL decreased with an increase in LiTFSA concentration. The self-diffusion coefficients of Li+, DEME+, and TFSA− dissolved in the IL were measured by using the pulsed-field-gradient spin-echo (PGSE) NMR method. The self-diffusion coefficient of each ionic species was also found to decrease with increasing concentration of LiTFSA. The limiting current density in the IL electrolyte was evaluated by chronoamperometry using symmetric Li|IL|Li cell. The results suggest that the diffusion process of Li(I) in the IL dominates the limiting current density in the cell. The highest limiting current density is achieved at a concentration of 0.64 mol dm−3 of LiTFSA. 相似文献
992.
A domain of attraction (DOA) analysis has been performed for a simplified model of the primary circuit of a pressurized water nuclear power plant, the Paks Nuclear Power Plant in Hungary. A simple two dimensional autonomous hybrid differential equation model of the controlled primary circuit has been developed for the purpose of the stability analysis that contains both continuous and discrete variables. It has been shown that the DOA of the controlled system encapsulates the operating domain for any positive value of the considered feedback gain of the power controller and the reactor power. However, the gain has a great impact on the dynamics of the controlled system that is also investigated, and a practically advantageous domain of the gain has been determined. 相似文献
993.
Shoichiro Watanabe Masahiro KinoshitaKensuke Nakura 《Journal of power sources》2011,196(16):6906-6910
Nickel-based oxide cathode material taking out from lithium-ion cell after storage for 2 years at 45 °C is analyzed by electron energy-loss spectroscopy in a scanning transmission electron microscope (STEM-EELS) and the result of STEM-EELS is compared with cobalt-based oxide cathode material which is treated as same manor as nickel-based oxide cathode material. The Ni-L2,3 energy-loss near-edge structure (ELNES) spectra of nickel-based oxide cathode material show peak positions similar to original material before storage. This result indicates that nickel-based oxide material has no significant change in the surface structure. On the other hand, a remarkable shift to low energy is observed in the Co-L2,3 ELNES spectra of the cobalt-based oxide cathode material after storage. The cycle test at 60 °C under the conditions of aggressive driving cycle (US06) mode for the nickel-based oxide cathode/graphite cell is also carried out. It is clear that cycle performance of the nickel-based oxide cathode/graphite cell is dependent on the depth of discharge (DOD). 相似文献
994.
Recent methodological and instrumental advances in solution-state nuclear magnetic resonance have opened up the way to investigating challenging problems in structural biology such as large macromolecular complexes. This review focuses on the experimental strategies currently employed to solve structures of protein–DNA complexes and to analyse their dynamics. It highlights how these approaches can help in understanding detailed molecular mechanisms of target recognition. 相似文献
995.
996.
运用项目质量管理理论,结合秦山核电二期工程的建设实践对质量规划、质量保证和质量控制分别展开讨论,通过运用以上质量管理的理论和控制技术,在实际指导项目质量管理过程中起到了积极的作用,具有较强的实用性。 相似文献
997.
998.
This paper summarizes the work done in the SARNET European Network of Excellence on Severe Accidents (6th Framework Programme of the European Commission) on the capability of the ASTEC code to simulate in-vessel corium retention (IVR). This code, jointly developed by the French Institut de Radioprotection et de Sûreté Nucléaire (IRSN) and the German Gesellschaft für Anlagen und Reaktorsicherheit mbH (GRS) for simulation of severe accidents, is now considered as the European reference simulation tool.First, the DIVA module of ASTEC code is briefly introduced. This module treats the core degradation and corium thermal behaviour, when relocated in the reactor lower head. Former ASTEC V1.2 version assumed a predefined stratified molten pool configuration with a metallic layer on the top of the volumetrically heated oxide pool. In order to reflect the results of the MASCA project, improved models that enable modelling of more general corium pool configurations were implemented by the CEA (France) into the DIVA module of the ASTEC V1.3 code.In parallel, the CEA was working on ASTEC modelling of the external reactor vessel cooling (ERVC). The capability of the ASTEC CESAR circuit thermal-hydraulics to simulate the ERVC was tested. The conclusions were that the CESAR module is capable of simulating this system although some numerical and physical instabilities can occur. Developments were then made on the coupling between both DIVA and CESAR modules in close collaboration with IRSN. In specific conditions, code oscillations remain and an analysis was made to reduce the numerical part of these oscillations. A comparison of CESAR results of the SULTAN experiments (CEA) showed an agreement on the pressure differences.The ASTEC V1.2 code version was applied to IVR simulation for VVER-440/V213 reactors assuming defined corium mass, composition and decay heat. The external cooling of reactor wall was simulated by applying imposed coolant temperature and heat transfer coefficient (HTC). The obtained results (pool temperatures, heat flux distribution, reactor wall ablation) were compared with available predictions of other codes. The agreement was correct, in particular on the shape and depth of ablation, as well as the maximum heat flux in case of a thick metallic layer, while ASTEC calculated a lower maximum heat flux for a thin metallic layer. 相似文献
999.
Hing Wah Chan David G. Howitt Alan B. Harker 《Journal of the American Ceramic Society》1989,72(6):1040-1043
The microstructures of simulated tailored ceramic forms for the Idaho Chemical Processing Plant (ICPP) high-level waste were characterized by TEM. The ceramic forms were consolidated from simulated ICPP waste calcines with either silicayttria-based or silica–lithia-based additives by hot isostatic pressing. The hot isostatically pressed ceramic waste forms are composed of cubic CaF2 , monoclinic ZrO2 , stabilized cubic ZrO2 , tetragonal ZrSiO4 , and amorphous silicate phases which can be phase separated. The phaseseparated glass is a result of phase immiscibility in the soda aluminosilicate glass to the compositions of albite and mullite. 相似文献
1000.
A.Ted WATSON Jinsoo UH 《青岛大学学报(工程技术版)》2004,19(3):1-12
核磁共振技术(NMR)是一种有力而安全的用于获取介质的空间分辨信息的方法。分析NMR数据的新方法能提供研究各种物理体系的机遇。本文讨论了核磁探针法的实验和分析进展。该方法用于定量评价表征流体和其在多孔介质中的流动行为。这种探针法的核心是辅助函数评价问题的求解,而这类问题的求解决依赖于用B spline表示法对未知函数的规整化和序列评估。 相似文献