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914.
本文介绍了基于可编程控制器PLC技术的备自投装置的设计思路,通过对输入输出方式,逻辑判断条件,软件编程等方面的分析,说明该装置在中压环网柜备自投控制功能方面的实际应用,最后展望该装置的应用前景。 相似文献
915.
Wan Zakiah Wan Ismail Kok Swee Sim 《International journal of imaging systems and technology》2011,21(3):280-289
Image processing requires an excellent image contrast‐enhancement technique to extract useful information invisible to the human or machine vision. Because of the histogram flattening, the widely used conventional histogram equalization image‐enhancing technique suffers from severe brightness changes, rendering it undesirable. Hence, we introduce a contrast‐enhancement dynamic histogram‐equalization algorithm method that generates better output image by preserving the input mean brightness without introducing the unfavorable side effects of checkerboard effect, artefacts, and washed‐out appearance. The first procedure of this technique is; normalizing input histogram and followed by smoothing process. Then, the break point detection process is done to divide the histogram into subhistograms before we can remap the gray level allocation. Lastly, the transformation function of each subhistogram is constructed independently. © 2011 Wiley Periodicals, Inc. Int J Imaging Syst Technol, 21, 280‐289, 2011; 相似文献
916.
917.
With increasing molybdenum ore mining, the difficult to treat ores, i.e., lower-grade and fine-disseminated ores have gradually increased in importance. Kerosene was widely used as the conventional collector of molybdenum flotation all along, but it does not adapt well to the flotation of molybdenite in difficult to treat ores. Meanwhile, kerosene has been cancelled from the manufacture catalogue in China, which makes large refineries no longer produce it, and in turn makes it difficult for a molybdenum flotation plant to purchase kerosene and makes it even harder for kerosene to keep a stable composition. Therefore, many molybdenum flotation plants began to apply diesel oil instead of kerosene as collector for molybdenite. However, the flotation results reveal that diesel oil from different manufacturers or being of different specifications from the same manufacturers has a different effect on the flotation of molybdenite, and pulp temperature has an obvious effect on the flotation efficiency of diesel oil. In pulp temperatures ranging from 10 to 30 °C, the flotation recovery of molybdenite increases with increasing high-boiling component in diesel oil. When pulp temperature is below 10 °C, the flotation recovery of molybdenite is related to the dispersibility of diesel oil, i.e., the proportion of high-boiling and low-boiling component in diesel oil. Therefore, a molybdenum flotation plant should not blindly apply diesel oil instead of kerosene as the collector for molybdenite, but should select diesel oil that is suitable for the properties of its ore. This technical note is helpful to better select the proper collector for a molybdenum flotation plant. 相似文献
918.
Chang‐Yong Wu Yong‐Zhen Peng Chun‐Li Wan Shu‐Ying Wang 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2011,86(3):461-467
BACKGROUND: In this study, a plug‐flow A2O (anaerobic/anoxic/oxic) reactor, with a working volume of 52.5 L, was employed to investigate the performance of biological nutrients removal and microbial population variations when treating low C/N ratio domestic wastewater. RESULTS: Results showed that TN removal was significantly affected by the shortage of carbon source while phosphorus removal was only slightly affected. The effluent soluble orthophosphate‐phosphorus (SOP) concentration was lower than 0.50 mg L?1 but the TN concentration was over 20 mg L?1 when the C/N ratio was 4.43. There was denitrifying phosphorus removal in the anoxic reactor and this was enhanced by increasing the volume ratio of anoxic reactor and maintaining appropriate mixed liquor recycle rate. More than 60% of the SOP were removed in anoxic reactors by denitrifying phosphorus removal when the volume ratio of anaerobic/anoxic/oxic was 1/1.4/1.6 and the mixed liquor recycle rate was 250%. The TN concentration of effluent decreased to 11.34 mg L?1 and SOP concentration was still lower than 0.5 mg L?1 in this condition. The main microorganisms found in the process by polymerase chain reaction‐denaturing gradient gel electrophoresis (PCR‐DGGE) and the functional biodiversity are discussed. CONCLUSION: Traditional design and operating parameters of A2O are not appropriate for treating low C/N wastewater. Enhancing the denitrifying phosphorus removal ratio in an A2O process is an effective way to increase the removal rate of N and P from low C/N wastewater. Copyright © 2010 Society of Chemical Industry 相似文献
919.
Meng Tian Feng Chen Wei Song Yancheng Song Yuanwei Chen Changxiu Wan Xixun Yu Xiaohua Zhang 《Journal of materials science. Materials in medicine》2009,20(7):1505-1512
The purpose of this study was to investigate in vivo biocompatibility and osteogenesis as well as degradability of the porous
strontium-doped calcium polyphosphate (SCPP) scaffolds as a biomaterial for bone substitute applications. The evaluation was
performed on a rabbit model over a period of 16 weeks by histology combined with image analysis, X-ray microradiography and
immunohistochemistry methods. The histological and X-ray microradiographic results showed that the SCPP scaffold exhibited
good biocompatibility and extensive osteoconductivity with host bone. Moreover, a significant more bone formation was observed
in the SCPP group compared with that in the CPP group, especially at the initial stage after implantation. New bone volumes
(NBVs) of the SCPP group determined at week 4, 8 and 16 were 14, 27 and 45%, respectively. Accordingly, NBVs of the CPP group
were 10, 19 and 40%. Immunohistochemical results revealed that both the expression of collagen type I and bone morphogenetic
proteins in the SCPP group were higher than that in the CPP group, which might be associated with the release of strontium
ions during the implantation. In addition, during 16 weeks implantation the SCPP scaffold exhibited similar degradability
with the CPP scaffold in vivo. Both scaffolds showed the greatest degradation rate for the first 4 weeks, and then the degradation
rate gradually decreased. The results presented in this study demonstrated that SCPP scaffold can be considered as a biocompatible
material, making it attractive for bone substitute application purposes. 相似文献
920.
This article presents solar energy or specifically the solar photovoltaic (PV) development outlook in Malaysia. The paper first introduces the massive potential of solar energy in the country, the key players in the solar energy development and the early solar energy policies, and programmes in the country. The most important to the PV development is the Malaysia Building Integrated Photovoltaic initiative, which is presented in this paper followed by an explanation on the Feed-in Tariff recently introduced in the country to encourage new solar PV projects. The outlook for solar PV in Malaysia is optimistic and as the uptake of solar PV increases, the unit cost is coming down rapidly. Solar PV is expected to be the most competitive Renewable Energy (RE) source, with the potential to achieve grid parity for electrical power in the country in the near future, and surpassing all other REs combined by 2050. 相似文献