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21.
Fifteen studies of family-school interventions with preschool children conducted between 1980 and 2002, and published in peer-reviewed journals, were reviewed and evaluated according to the criteria developed by the Task Force on Evidence-Based Intervention in School Psychology (Division 16 and Society for the Study of School Psychology Task Force, 2003). Results indicate that family-school interventions with preschool children have taken many forms, have targeted a variety of problems and behaviors, and have generally shown positive effects. Efficacious interventions included parent and teacher training, parent education, and behavioral family therapy. Recommendations for future research include increased methodological rigor, replication and extension of current studies, and the completion of longer-term, follow-up investigations to determine whether gains that are made post-treatment are maintained over time. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
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23.
The response of a granular chain to impulse loading was investigated as a function of material properties. Using COMSOL Multiphysics, the elastic modulus and density of the grains were varied while the piston and force sensor properties remained fixed. The result of solitary wave propagation through the granular chain was recorded at the force sensor as a series of reaction force waves. It was found that wave velocity and amplitude increased with elastic modulus. Increasing density caused a decrease in wave velocity and an increase in amplitude. In addition, higher density granular chains exhibited a decrease in the number of waves in their respective reaction force wave trains. LS-DYNA was then used to explore the response of a variety of ceramic and metallic granular chains. Density, elastic modulus, and Poisson’s ratio were all set to representative values for the respective material. It was found that solitary wave development and decay occurred at different rates for different materials. In addition, the kinetic energy decay of the impactor was slower for glass compared with tungsten. Finally, it was shown that a single reaction force wave with no train could be produced by impacting a high density, high modulus chain such as tungsten with a glass piston, which has relatively low density and elastic modulus. Increasing impact velocity for this case resulted in a single high-amplitude wave with no train. 相似文献
24.
Mark Carlson 《Journal of Network and Systems Management》2014,22(4):709-715
Hosted by the Distributed Management Task Force (DMTF) and collocated with the International Conference on Network and Service Management, SVM 2013 was the seventh International DMTF Academic Alliance Workshop on Systems and Virtualization Management (SVM). SVM 2013 was held in Zurich, Switzerland on October 18, 2013. Featuring seven presentations surrounding cloud, OpenSAF, open standards, and CIM, SVM 2013 also included a joint poster session with another workshop, an invited talk by a guest speaker, a keynote speech given by the DMTF President, Jeff Hilland, and closed with an informal interactive group discussion. 相似文献
25.
Streets SS Henderson SA Stoner AD Carlson DL Simcik MF Swackhamer DL 《Environmental science & technology》2006,40(23):7263-7269
Water from Lake Michigan and fish from all five Great Lakes have been sampled and analyzed for a suite of six polybrominated diphenyl ether (PBDE) congeners and 110 polychlorinated biphenyl congeners (PCBs). The Lake Michigan dissolved phase PBDE congener concentrations (0.2 to 10 pg/L) are similar to dissolved phase PCB congener concentrations (nondetected to 13 pg/L). Partitioning of PBDEs between the particulate and dissolved phases exhibits behavior similar to that of PCBs. Organic-carbon-normalized water-particle partition coefficients (log K(OC)s) ranged from 6.2 to 6.5. Lake trout are depleted in BDE-99 relative to dissolved phase concentrations, and in contrast to what is expected from the PCB congener patterns. This reflects suspected debromination of BDE-99 in the food web of Lake Michigan. A regression of the log of the bioaccumulation factor (BAF) and the log of the octanol-water partition coefficent (K(OW)) indicated a positive relationship for both PCB congeners and PBDE congeners. BDE-99 does not appear to followthe same trend, a further indication that it is subject to biotransformation. Using the PBDE BAFs for Lake Michigan and the PBDE fish concentrations from the other Great Lakes it is expected that the dissolved phase concentrations of congeners in the other lakes would range from 0.04 to approximately 3 pg/L. 相似文献
26.
A. Chaudhry R. Kleiman K. D. Carlson 《Journal of the American Oil Chemists' Society》1990,67(11):863-866
Routine analysis of fatty ester fractions ofLesquerella fendleri oil suggested the presence of epoxy compounds and other minor components. By a combination of open silica column and high
performance liquid chromatography (HPLC) fractionations of the methyl esters prepared from the oil, these constitutents were
isolated and then characterized by thin-layer chromatography-mass spectrometry (GC-MS—electron ionization, EI, and chemical
ionization, CI) and nuclear magnetic resonance (NMR—1H and13C). Three epoxy acids, 15,16-epoxy-9,12-octadecadienoic, 9,10-epoxy-12-octadecenoic and 9,10-epoxy-octadecanoic, were found.
Hydroxy acids present included a C-22 homologue of lesquerolic acid (16-hydroxy-12-docosenoic acid) and 14,15-dihydroxy-tricosanoic
acid. Other minor ocmponents included four sterols, brassicasterol, campesterol, β-sitosterol and stigmasterol, and a series
of saturated and unsaturated fatty acids up to C30.
Visiting postdoctoral scientist sponsored by the government of India. 相似文献
27.
Several deposits of dense natural clinoptilolite, including one from British Columbia, Canada, have been identified which exhibit both high zeolite content and essentially no macroporosity or intercrystalline voids. Sections of zeolite mineral from the British Columbia deposit were machined into thin membranes and used in the pervaporative desalination of water samples with varying salinity levels, including synthetic seawater. Essentially complete rejection of Mg2+ and Ca2+ (99.99% and 98.52%) and high levels of rejection of Na+ and K+ (over 97.5%) were observed when using a synthetic seawater feed at 75 °C and 1 atm feed-side pressure. Water flux through the natural zeolite membranes was dependent on the ion concentration in the feed, the operating temperature and the feed salinity. At 93 °C, water fluxes of 2.5 kg/m2·h and 0.39 kg/m2·h were obtained for feed concentrations of 100 mg/L Na+ and 5500 mg/L Na+, respectively. The high ion rejection and water flux observed for these rugged and economical natural clinoptilolite membranes indicates their potential utility for desalination applications. 相似文献
28.
Tianhao Wang Harpreet Sidhar Yuri Hovanski Piyush Upadhyay Blair Carlson 《Science & Technology of Welding & Joining》2018,23(3):249-255
Friction stir scribe technology, a derivative of friction stir welding, was applied for the dissimilar lap welding of an aluminium alloy and galvanised mild steel sheets. During the process, the rotating tool with a cobalt steel scribe first penetrated the top material – aluminium – and then the scribe cuts the bottom material – steel. The steel was displaced into the upper material to produce a characteristic hook feature. Lap welds were shear tested, and their fracture paths were studied. Welding parameters affected the welding features, including hook height, which turned out to be highly related to fracture position. Therefore, in this paper, the relationships among welding parameters, hook height, joint strength and fracture position are presented. In addition, the influence of zinc coating on joint strength was also studied. 相似文献
29.
Tributary confluences are dynamic thermal refuges for a juvenile salmonid in a warming river network
Terrance Wang Suzanne J. Kelson George Greer Sally E. Thompson Stephanie M. Carlson 《河流研究与利用》2020,36(7):1076-1086
As rivers warm, cold‐water fish species may alleviate thermal stress by moving into localized thermal refuges such as cold‐water plumes created by cool tributary inflows. We quantified use of two tributary confluence plumes by juvenile steelhead, Oncorhynchus mykiss, throughout the summer, including how trout positioned themselves in relation to temperature within confluence plumes. At two confluences, Cedar and Elder creeks, along the South Fork Eel River, California, USA, we monitored temperatures using in situ logger grids throughout summer 2016. Fish were counted within confluences via snorkel surveys five times a day on 5 days at each site. We found diel and seasonal dependence on confluence use by steelhead, especially at the Cedar Creek confluence, where mainstem temperatures exceeded 28°C. At this site, fish moved into the confluence on the warmest days and warmest times of the day. Fish observed within the Cedar Creek confluence plume were most common in locations between 20–22°C, rather than the coldest locations (14.5°C). At Elder Creek, where mainstem temperatures remained below 24°C, there was little relationship between mainstem temperature and steelhead presence in the confluence plume. At both sites, steelhead distribution within plumes was influenced by spatial variation of temperature and mean temperature in surveyed grid cells. Our results show that cool tributaries flowing into warmer mainstem reaches (over 24°C) likely create important thermal refuges for juvenile steelhead. As mainstem rivers warm with climate change, cool‐water tributary inputs may become more important for sustaining cold‐water salmonids near the southern end of their range. 相似文献
30.