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排序方式: 共有2901条查询结果,搜索用时 15 毫秒
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Markus W. Laimer Julia Engl Alexander Tschoner Susanne Kaser Andreas Ritsch Tobias Tatarczyk Markus Rauchenzauner Helmut Weiss Franz Aigner Josef R. Patsch Christoph F. Ebenbichler 《Lipids》2009,44(12):1125-1130
Obesity is associated with lipid abnormalities leading to an increased morbidity and mortality from atherosclerotic disease. Lipid transfer proteins such as Cholesteryl Ester Transfer Protein (CETP) and Phospholipid Transfer Protein (PLTP), and lipases such as lipoprotein lipase (LPL) and hepatic lipase (HL) are involved in the pathogenesis of the obesity associated proatherogenic dyslipidemia. Nineteen severely obese female subjects undergoing laparosopic gastric banding participated in this prospective study. Subjects were examined with respect to body composition, lipid profile, CETP, PLTP, LPL and HL before and 1 year after surgical treatment. Mean weight loss was 22.2 kg, mainly due to losses in the fat depots. Triglycerides decreased and HDL2-C increased significantly. In respect to transfer proteins mean CETP mass decreased from 1.82 to 1.71 μg mL?1 (P = 0.043) and mean PLTP activity was reduced from 7.15 to 6.12 μmol mL?1 h?1 (P = 0.002), in parallel. In addition, both mean LPL activity and mean HL activity tended to decrease from 297 to 248 nmol mL?1 h?1 for LPL (P = 0.139) and from 371 to 319 nmol mL?1 h?1 for HL (P = 0.170), respectively. We conclude that weight loss induced by bariatric surgery is associated with the amelioration of the obesity-associated dyslipidemic state. This improvement may be attributable to decreased mass and action of the adipocyte tissue derived lipid transfer proteins CETP and PLTP. 相似文献
74.
Valerian Dragutan Ileana Dragutan Helmut Fischer 《Journal of Inorganic and Organometallic Polymers and Materials》2008,18(1):18-31
Synthesis of a broad range of diverse polymers containing main group metals by the new ROMP approach starting from metal-functionalized
cyclic monomers and taking advantage of both classical and well-defined W-, Mo- and Ru-based metathesis catalytic systems
is critically surveyed. Emphasis is laid upon Si-containing ring-opening metathesis polymers, popular due to the easy accessibility
of the corresponding monomers and the valuable properties of the obtained polymers. Also highlighted is the production of
modern advanced materials based on metal-containing polymers as well as some of their multifarious applications. Future opportunities
for this field are finally outlined. 相似文献
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Research and development towards high efficiency plastic solar cells have been accelerating in recent years. Polymer-based bulk heterojunction solar cells are offering an attractive and inexpensive concept for large scale production by solution processing as well as advantageous flexible and aesthetic form factors. The thin film nano-morphology of bulk-heterojunction solar cells has been shown to dramatically influence the photovoltaic performance of the devices. This article reviews the different methods used to control the film nano-morphology of bulk-heterojunction solar cells focussing on the chemical additives during solution processing. All power conversion efficiency limiting mechanisms of bulk-heterojunction solar cells are discussed in detail. It is shown, how the formation of optimal percolation pathways between donor and acceptor influences the photovoltaic device performance. It is explained how the film nano-morphology relates to light absorption, free charge carrier generation as well as charge transport to the electrodes. 相似文献
77.
C. Bauer-Christoph Helmut Wachter Norbert Christoph Andreas Rßmann Ludwig Adam 《European Food Research and Technology》1997,204(6):445-452
Gas chromatography and the determination of natural isotope ratios are powerful analytical methods which can be used to check the authenticity of alcoholic beverages and to detect any adulteration. To check the origin and the authenticity of commercial fruit spirits, whiskies, etc., 197 samples were analysed by gas chromatography, 2H-NMR and 13C isotope mass spectrometry. The discrimination between different varieties was demonstrated by bivariate and multivariate discriminant analysis using different concentrations of volatile compounds such as methanol, butan-1-ol, 2- and 3-methyl-butanol, benzaldehyde and hexanol as well as isotopic data like (D/H)I, (D/H)II and 13C/12C isotopomers of ethanol. The results show that by using multivariate discriminant analysis it is possible to distinguish not only between different groups of spirits, e.g. those made of stone-fruit, malaceous fruit, grain and corn, but also between individual varieties, such as cherry, plum, mirabelle and apple. If the detection of highly rectified ethyl alcohol of agricultural origin and the identification of its raw materials are required, then natural isotope ratios are the only discriminant analytical parameters available. 相似文献
78.
Univ.-Prof. DI Dr. Helmut Habersack DI Marlene Haimann Ass. Prof. Dr. Sándor Baranya Prof. Dr. János Józsa Mag. Angelika Riegler Dr Christine Sindelar DI Marcel Liedermann Johanna Ficsor Gabriella Mohácsiné Simon HR DI Dr. Michael Hengl 《?sterreichische Wasser- und Abfallwirtschaft》2014,66(9-10):340-347
The multiple uses of the Danube River for navigation, hydropower production and as a drinking water supply influence its ecological quality. Flow restrictions due to regulation as well as impacts on the sediment regime such as retention in the catchment area and interruption of the sediment continuum result in changes of the hydromorphological structures and can produce major problems in the context of sediment management. In light of these facts, cross-border investigations of sediment transport at the Danube River are called for. As there are no uniform research approaches shared by Austria and Hungary, the EU-funded project SEDDON (Sediment Research and Management at the Danube River) aims to compare different monitoring and modeling techniques used to determine sediment transport, and to develop mutual solutions. Further, the laboratory equipment currently used for hydraulic model experiments is evaluated and a research channel with a free flowing discharge of up to 10 m3/s without pumping will be constructed, allowing large-scale joint laboratory tests concerning sediment to be performed. 相似文献
79.
Brice K. Grunert Shelby L. Brunner Sajad A. Hamidi Hector R. Bravo J. Val Klump 《Journal of Great Lakes research》2018,44(5):851-863
We present water column thermal structure for two climatically different years: 2012, which experienced abnormally warm spring and summer air temperatures preceded by a relatively low ice winter and 2013, which experienced cooler than average spring and average summer air temperatures and preceded by average ice conditions. Mean bottom water temperatures for the season and during cold water intrusions were significantly warmer in 2012 than 2013 leading to a significantly reduced stratified season in 2012. Cold water intrusions were driven into southern Green Bay by southerly winds while intrusions were terminated when winds switched to persistent northerly winds. 2012 observed a significant increase in northerly winds relative to 2013, decreasing cold water intrusion presence and duration but winds did not fully explain the difference in thermal conditions for southern Green Bay. These cold bottom waters drive stratification in polymictic southern Green Bay while dimictic waters were found to have significantly warmer bottom temperatures during 2012 and a deeper mixed layer. Our observations suggest that relatively shallow (<20?m), seasonally stratified systems may not increase in stratification strength and duration under a warming climate; rather, changing wind climatology and surface heat flux can inform the degree to which the mixing regime can be expected to change and impact stratification and thermal structure of coastal systems. We discuss the biogeochemical implications of different thermal regimes, particularly within the context of multiple drivers of physical water column structure in eutrophic, stratified coastal systems. 相似文献
80.
Automated analysis of submicron particles by computer-controlled scanning electron microscopy is generally possible. The minimum diameter of the detectable particles is dependent on the mean atomic number of the particles and the operating parameters of the scanning microscope. The main limitation with regard to particle size is set by the quality of the particle detection system, which generally is the backscatter electron detector. The accuracy of the results of the x-ray analyses is very often strongly affected by specimen damage, omnipresent especially for environmental particles even at low electron energies and probe currents. With the exception for light elements, the detection limit is approximately 1 wt%. Device-related limitations to automated analysis may be specimen drift and an unreliable autofocus function. 相似文献