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71.
The balance between low carbon development and rapid economic growth is a ‘Gordian knot’ for most countries. This study aims to explore the practicable route of lowering carbon intensity with the expansion of the Information and Communication Technologies (ICT) industry in China. Using the provincial panel data from 2000 to 2017, the paper employs five indicators to empirically investigate the determinant mechanism of carbon intensity based on the refined Stochastic Impact by Regression on Population, Affluence, and Technology (STIRPAT) and spatial econometric models. The findings demonstrate that the ICT industry is the main force in adjusting carbon intensity. Despite constraint by the rebound effect, the net effect of the ICT industry shows a significant positive impact on lowering carbon intensity under the consideration of spatial dependence. Furthermore, compared with developed regions, the contribution of ICT on regional inequality of carbon intensity shows a higher share in developing regions. By applying the Oaxaca-Ransom counterfactual decomposition, the results reveal that there are substantial regional gaps between multi-comparable groups. The composite effect of informatization, industrialization, and urbanization accounts for the major share of the regional gap. Thus, policymakers should pay more attention to enhancing the ICT infrastructure in developing regions, boosting the ICT-related technology investment in specific sectors, coordinating regional cooperation, and balancing the migration of skilled workers. 相似文献
72.
The Retail-Minus Rule (RMR) specifies that the rate for a mandated wholesale service is set by subtracting from the vertically integrated provider's (VIP's) retail price the costs it avoids by selling the wholesale service rather than the retail service. While the RMR offers regulators an expedient method for setting wholesale prices, we show that it is efficient only under restrictive conditions. The proper test for a price squeeze inquires whether the VIP's retail price is greater than or equal to the sum of the direct cost and the opportunity cost of supplying the retail service. The RMR passes this test only when the competing retail services are perfect substitutes. 相似文献
73.
Xi ZHANG Yong GENG Yen Wah TONG Harn Wei KUA Huijuan DONG Hengyu PAN 《Frontiers in Energy》2021,15(2):473
Low-carbon energy technology (LC) innovation contributes to both environmental protection and economic development. Using the panel data of 30 provinces/autonomous regions/municipalities in China from 1998 to 2017, this paper constructs a two-layer logarithmic mean Divisia index (LMDI) model to uncover the factors influencing the variation of the innovation of LC in China’s industrial sectors, including the alternative energy production technology (AEPT) and the energy conversation technology (ECT). The results show that China’s industrial LC patent applications rapidly increased after 2005 and AEPT patent applications outweighed ECT patent applications all the time with a gradually narrowing gap. Low-carbon degree played the dominant role in promoting the increase in China’s industrial LC patent applications, followed by the economic scale, R&D (research and development) efficiency, and R&D share. Economic structure contributed to the increases in LC patent applications in the central and the western regions, while led to the decreases in the eastern region, the north-eastern region, and Chinese mainland Xizang(Tibet) Autonoomous Region is not considered due to lack of data. This note applies to the entire article. . Low-carbon degree and economic scale were two main contributors to the growths of both industrial AEPT patent applications and ECT patent applications in Chinese mainland and the four regions. Several policy recommendations are made to further promote industrial innovation in China. 相似文献
74.
Ji Qi Yanhui Li 《International Journal of Adaptive Control and Signal Processing》2021,35(6):1062-1082
In the network environment, the single time-triggered scheme wastes limited bandwidth resources due to all the sampled data are transmitted to the networks, and the single event-triggered scheme may increase system error because of ignoring factors such as changes in network utilization. To reduce the design conservatism, this paper is concerned with the hybrid-triggered L1 fault detection filter design for a class of nonlinear networked control systems (NCSs) described by Takagi–Sugeno (T-S) fuzzy model. Taking the effects of time-triggered scheme and event-triggered scheme into consideration simultaneously, we construct a fuzzy fault detection system. New results on stability and L1 performance are proposed for fuzzy fault detection system by exploiting the Lyapunov–Krasovskii functional and by means of the integral inequality method. Specially, attention is focused on the design of fault detection filter that guarantees a prescribed L1 noise attenuation level . Finally, two examples are presented to demonstrate the effectiveness of the proposed method. 相似文献
75.
Jun Liu Yuhui Zhao Hao Xu Xiaolu Zhao Yutian Tan Peipei Li Dongdong Li Yingmei Tao Dunhua Liu 《International Journal of Food Science & Technology》2021,56(6):3044-3054
The present study aims to examine fruit cell wall-associated fruit softening in Lycium barbarum L. by the microstructure of the fruit cells and the changes in the contents of cell wall components, molecular weights of cell wall polysaccharides and the activities of related cell wall degrading enzymes at different development stages of L. barbarum L. fruit. Fruit firmness significantly declined during ripening, with the greatest reduction between the 28 and 35 days stages. The decrease in firmness correlated with an extensively deformed microstructure in the parenchyma tissues and positively correlated with reductions in the contents of fruit cell wall materials and molecular weight in cell wall polysaccharide. Cellulase, α-galactosidase, polygalactosidase and pectin methylesterase showed higher activities during 28 days; whereas, the activities of β-galactosidase were higher during 35 days. These results indicate that cell wall-related processes are a key feature of early softening in L. barbarum L. 相似文献
76.
《International Journal of Hydrogen Energy》2022,47(97):41097-41110
The present work was focused on the corrosion properties and contact resistance behavior of poly(orthophenlyenediamine) (PoPD) coating on 316L SS bipolar plates. To reduce the corrosion rate and increase the interfacial conductivity of 316L SS bipolar plates, PoPD coating was deposited using an electropolymerization technique by the various monomer concentration of orthophenlyenediamine (oPD) on its surface. The presence of 1, 2, 4, 5- tetra substituted benzene nuclei of phenazine units in the polymer coating was confirmed by infrared spectroscopy. X-ray photoelectron spectroscopy analysis has confirmed the (%) of chemical composition in PoPD coating. The results of scanning electron microscopy analysis revealed that the uniform and compact coating with complete cover on 316L SS. The corrosion properties were investigated in 0.5 M H2SO4 and 2 ppm HF solution at 80 °C. The polarization test results showed that the PoPD coating reduced the corrosion current density both in the PEMFC anode and cathode environments. The charge transfer resistance values were in the order of 316L SS ? 0.02 M PoPD ? 0.06 M PoPD ? 0.04 M PoPD. A very low interfacial contact resistance and good adhesion strength was observed for 0.04 M PoPD coating. The higher contact angle of 0.04 M PoPD coating explained the hydrophobic property and more benefit of water management in the PEMFC environment. The results of the analysis of total metal ion releases clearly explained that the low level of metal ions released for 0.04 M PoPD coating. The overall studies revealed the PoPD coating with optimized 0.04 M oPD concentration showed best performance and provided more anodic protection to 316L SS bipolar plates. 相似文献
77.
春哲铁矿位于南冈底斯火山—岩浆弧带,谢通门—墨竹工卡铜、铁、铅、锌、金成矿带(Ⅳ5),麦热—空朗金银铜铅锌成矿远景区,成矿地质条件优越。在总结区内地层、构造、岩浆成矿背景及成矿条件,航磁、物探特征的基础上结合前人工作成果,对区内找矿潜力进行分析。重点介绍根据航磁异常利用地质、物探方法寻找铁矿取得的效果,在区域上寻找同类型矿床具有一定的参考作用。 相似文献
78.
分析了龙门山石灰石矿区的区域稳定性及采矿生产活动可能诱发的各种环境地质问题,并针对性地提出防治对策。 相似文献
79.
在多年瓦斯地质研究的实践基础上,研究矿区、矿井、采掘工作面瓦斯地质图的作用和编制方法,运用板块构造和区域地质演化理论,做到区域控制矿区,矿区控制矿井,矿井控制采区和采煤工作面.结合大量的瓦斯地质资料和瓦斯测试参数,搞清瓦斯地质规律、赋存规律和涌出规律、瓦斯突出危险性的分区分带特征,编制三级彩色瓦斯地质图.认为瓦斯地质图是指导煤矿瓦斯治理的最重要的基础和技术,使瓦斯地质规律一目了然,指导瓦斯灾害预测、防治和瓦斯资源开发利用,有的放矢综合治理瓦斯. 相似文献
80.