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61.
The potential benefits of providing geocell reinforced sand mattress over clay subgrade with void have been investigated through a series of laboratory scale model tests. The parameters varied in the test programme include, thickness of unreinforced sand layer above clay bed, width and height of geocell mattress, relative density of the sand fill in the geocells, and influence of an additional layer of planar geogrid placed at the base of the geocell mattress. The test results indicate that substantial improvement in performance can be obtained with the provision of geocell mattress, of adequate size, over the clay subgrade with void. In order to have beneficial effect, the geocell mattress must spread beyond the void at least a distance equal to the diameter of the void. The influence of the void over the performance of the footing reduces for height of geocell mattress greater than 1.8 times the diameter of the footing. Better improvement in performance is obtained for geocells filled with dense soil. 相似文献
62.
C. T. Liu Ph.D. K. S. Kumar Ph.D. 《JOM Journal of the Minerals, Metals and Materials Society》1993,45(5):38-44
This article summarizes recent progress in research and development on nickel and iron aluminide intermetallic alloys. Ordered intermetallics possess attractive properties for structural applications at elevated temperatures in hostile environments; however, brittle failure and poor fracture resistance limit their use as engineering materials. In recent years, efforts to understand this brittle fracture behavior have identified both intrinsic and extrinsic factors governing brittle fracture. Parallel work on alloy design using physical metallurgy principles has led to the development of aluminide alloys with improved mechanical and metallurgical properties for structural use. 相似文献
63.
Studies were conducted on harvesting of Bacillus thuringiensis (Bt)-based biopesticides from fermented broths of starch industry wastewater (SIW), wastewater sludge (raw and hydrolyzed-NH and TH, respectively) and semi-synthetic soyameal to enhance entomotoxicity (Tx) by centrifugation. Pertinent factors influencing Tx, solids concentration, pH, temperature and centrifugal force were investigated. The centrifugate solids concentration beyond 100 g/l did not enhance Tx, instead caused pellet formation. Centrifugation efficiency (Tx recovery) was higher at pH 4, and temperature 20 degrees C for starch wastewater (98%), wastewater sludge (98% and 97.8% for non-hydrolyzed and hydrolyzed, respectively) and soya broth (83%). For maximum Tx recovery (SIW-95%; NH-90%; TH-98% and soya-78%), the centrifugal force and time required was 48,000 g and 30 min, respectively. Losses in recovery efficiency were lower for SIW and wastewater sludge in comparison to soya on adopting commercially recommended centrifugal force of 9000 g. The settling velocity computations for different fermented broths enabled calculation of Sigma factor for continuous commercial centrifuge of a given capacity and hence simulation of power requirements. It was established that power requirements for a given Tx recovery efficiency were highest for conventional medium (soya) in comparison to other waste-based fermented broths. 相似文献
64.
雅法,是世界上最古老的城市之一,有4000多年的历史,面临地中海。项目中的这座古宅就坐落在这座曾经辉煌的城市中,它庄严辉煌的开口也同样正面对着地中海,可以俯瞰整个海面。虽然我们现在已经很难确定建筑确切年纪,不过很清楚的是,它已有上百年的历史了。 相似文献
65.
Brajendra Kumar Singh Jeremy Coulter Mohammad Abdul Ghani Sayani Syed M. Sami Mohammad Khalid Kemal E. Tepe 《The International journal of environmental studies》2013,70(5):765-776
Communication systems are needed to integrate generated power from wind farms with the electrical grid. This paper provides a comprehensive review of available communication technologies, protocols and objectives related to wind energy and electrical grid integration. This paper summarizes the communication system solutions for wind generation. A major obstacle is an absence of unified communication architectures and standards. 相似文献
66.
Stenotrophomonas,Mycobacterium, and Streptomyces in home dust and air: associations with moldiness and other home/family characteristics 总被引:1,自引:0,他引:1
E. Kettleson S. Kumar T. Reponen S. Vesper D. Méheust S. A. Grinshpun A. Adhikari 《Indoor air》2013,23(5):387-396
Respiratory illnesses have been linked to children's exposures to water‐damaged homes. Therefore, understanding the microbiome in water‐damaged homes is critical to preventing these illnesses. Few studies have quantified bacterial contamination, especially specific species, in water‐damaged homes. We collected air and dust samples in twenty‐one low‐mold homes and twenty‐one high‐mold homes. The concentrations of three bacteria/genera, Stenotrophomonas maltophilia, Streptomyces sp., and Mycobacterium sp., were measured in air and dust samples using quantitative PCR (QPCR). The concentrations of the bacteria measured in the air samples were not associated with any specific home characteristic based on multiple regression models. However, higher concentrations of S. maltophilia in the dust samples were associated with water damage, that is, with higher floor surface moisture and higher concentrations of moisture‐related mold species. The concentrations of Streptomyces and Mycobacterium sp. had similar patterns and may be partially determined by human and animal occupants and outdoor sources of these bacteria. 相似文献
67.
This article presents experimental results of the effect of methanol gasoline blends as alternate fuels for the spark ignition (SI) engine. As the cost of the gasoline is periodically increasing the quest for the alternative fuels are evolved with which the emissions are reduced along with improved engine performance. A set of experiments have been conducted to investigate the effect of gasoline methanol blends in methanol percentages of M5, M10 and M15 on the engine performance and emissions. A significant reduction in emissions is observed with methanol blends compared to the standard gasoline with improved engine performance and emission characteristics. The fuels blends ranging from M10 to M15 have been found suitable for reduced emissions and improved engine performance. 相似文献
68.
India is one of the largest growing economies in the world. It has a GDP of 2487.94 billion US dollars as of 2017. Around 61.297% of power generation is by utilising abundantly available lignite blended with imported coal. India is slowly cutting out its demand for imported coal from other countries. It has built its own lignite-based power plant to overcome the need of imported coal. The impact on cost of electricity (COE) and net power output (NPO) after retrofitting carbon capture and storage (CCS) over a lignite-based power plant of India is analysed. In this paper, a feasibility study is carried out for NLC India Ltd Barsingsar power plant by retrofitting CCS. The results obtained from the Integrated Environmental Control Model (IECM) Software are positively strong enough to encourage CCS implementation. Various strategies for utilising the CO2 capture and carbon storage sites are suggested. 相似文献
69.
Motorisation and fast depletion of fossil fuel reserves and issues like global warming have led the researchers all over to look for substitute fuels. Biodiesel resulting from vegetable oil is being used around the globe to lessen air pollution and reduce the necessity of diesel fuel. The current study covers the various aspects of N20 neem biodiesel with increased fuel injection pressure. The blends of N20 were tested with increased fuel injection pressure to examine the characteristics such as brake thermal efficiency, fuel consumption, emission and combustion parameters. Experimental results indicated that N20 with 240?bar has a closer performance to diesel, reduced exhaust emission and improved combustion parameters. 相似文献
70.
This paper presents an account of a research project concerned with the application of artificial intelligence techniques to structural design in civil engineering. INDEX is a rule-based system for the design of industrial buildings that is being developed at the University of Edinburgh. It has a blackboard architecture and its knowledge base is organized into a hierarchy of two levels. The main focus of this paper is to summarize the implementation aspects of one of its knowledge modules, ALTSEL which is responsible for the preliminary design. The organization of knowledge inside the ALTSEL module is briefly outlined using a number of representative rules from its sub-modules. The use of the Edinburgh PROLOG Blackboard Shell in the development of INDEX is also described briefly. 相似文献