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991.
Protein components extracted from the barley varieties, Prior and Beecher, have been electrophoretically separated in acrylamide gels. The resolution obtained was sufficiently definitive to allow scanning by transmission densitometry. With the same solvent, similar electrophoretic patterns were obtained over a number of sequential extractions. However, with different solvents the patterns showed that individual proteins had been extracted in different proportions. The work presented emphasizes the need for clarification of the relative importance of the separated proteins. 相似文献
992.
A mechanism for creating an enantioenrichment in the amino acids, the building blocks of the proteins, that involves global selection of one handedness by interactions between the amino acids and neutrinos from core-collapse supernovae is defined. The chiral selection involves the dependence of the interaction cross sections on the orientations of the spins of the neutrinos and the (14)N nuclei in the amino acids, or in precursor molecules, which in turn couple to the molecular chirality. It also requires an asymmetric distribution of neutrinos emitted from the supernova. The subsequent chemical evolution and galactic mixing would ultimately populate the Galaxy with the selected species. The resulting amino acids could either be the source thereof on Earth, or could have triggered the chirality that was ultimately achieved for Earth's proteinaceous amino acids. 相似文献
993.
A study was conducted to evaluate the effects of a direct-fed microbial (M) and dietary glycerol (G) on milk yield, efficiency of yield, and nutrient digestibility during hot weather. Sixty Holstein cows averaging 120 d in milk (DIM) and 36.2 kg/d of milk were used in a 12-wk 2 × 2 factorial design trial from June through September 2008. Cows were fed a common diet during the 2-wk standardization period and were blocked by milk yield, DIM, parity, and dry matter intake. Diets were based on corn and ryegrass silages and balanced to be isocaloric and isonitrogenous. Treatments included a negative control (M− or G−), 4 × 109 cfu/head of a combination of Lactobacillus acidophilus NP51 and Propionibacterium freudenreichii NP24 (M+), control plus 400 g/h per day of 99% pure food-grade glycerol (G+), and 4 × 109 cfu/h per day of a combination of Lactobacillus acidophilus NP51 and Propionibacterium freudenreichii NP24 plus 400 g/h per day of 99% pure food-grade glycerol (MG++). No interactions were observed between direct-fed microbials and dietary glycerol in the study except on apparent nutrient digestibility. No differences were observed in dry matter intake, which averaged 22.7, 23.1, 23.4, and 22.9 for M−, G−, M+, and G+, respectively. Milk yield was increased for M+ compared with M− at 34.1 and 31.7 kg/d, but G+ had no effect on yield. No treatment effect was noted for milk fat percentage or milk protein percentage among diets. Milk protein yield was higher for M+ compared with M− at 0.93 versus 0.87 kg/d. Energy-corrected milk was improved for the M+ versus M− groups at 33.5 and 31.6 kg/d, respectively. No differences in respiratory rate, skin temperature, body temperature, or concentrations of serum glucose or urea N were observed among treatments. Improvement in apparent digestibility was observed with M+ and G+ compared with M−/G− in this experiment. The addition of a direct-fed microbial alone improved milk and protein yield, energy-corrected milk, and apparent digestibility of crude protein, neutral detergent fiber, and acid detergent fiber, and the inclusion of glycerol (G+) had a positive effect on apparent dry matter and acid detergent fiber digestibility compared with M−/G−. The addition of a direct-fed microbial and dietary glycerol may improve yield and digestibility for cows subject to heat stress. 相似文献
994.
995.
The first in a series of papers which are directed towards facilitating the analysis and design of journal bearings. By employing computer techniques, numerical solutions of Reynolds' equation are obtained for centrally-loaded bearings having arcs of β = 360°, 180°, 120° and 60° for the widely used case of L/D = 1. Assumptions are based on constant viscosity and no film rupture. Performance curves are presented which eliminate the need for side leakage factors; the ease of application of the charts is shown by two illustrative problems. The effect of changing such design parameters as bearing clearance is illustrated. 相似文献
996.
Richard Fowler 《EDPACS》2013,47(3):13-16
Abstract Crime by Computer, by Donn B. Parker. Charles Scribner's Sons (597 Fifth Avenue, New York, NY, 10017). 1976, 308 pages, $10.95. The Cost of Crimes Against Business. U. S. Department of Commerce. (Order from Superintendent of Documents, U. S. Government Printing Office, Washington, DC, 20402.) 1976, 52 pages, $1.60. 相似文献
997.
It is shown that many system stability and robustness problems can be reduced to the question of when there is a quadratic Lyapunov function of a certain structure which establishes stability of x = Ax for some appropriate A. The existence of such a Lyapunov function can be determined by solving a convex program. We present several numerical methods for these optimization problems. A simple numerical example is given. 相似文献
998.
P. W. Fowler J.P. B. Sandall S. J. Austin 《Fullerenes, Nanotubes and Carbon Nanostructures》2013,21(3):369-384
Abstract Calculations are performed on optimal geometries and relative stabilities of 48 new candidates for the structure of the experimentally identified but as yet uncharacterised C70H36 molecule. Three structures with entirely unconjugated π systems, which differ only in the siting of the double bond in each polar pentagon, are more stable than all others by ~ 45 kJ mol?1 in the MNDO model. Localisation alone does not ensure stability, but the low strain of this particular arrangement apparently outweighs the total loss of π delocalisation energy. 相似文献
999.
This paper presents a comprehensive framework for the strategic capacity expansion of production equipment in semiconductor manufacturing, and the proposed approach is applied to a model of an actual wafer fabrication facility. It is the intention of this work to show that, once intelligently integrated, an analytical queueing model and a numeric computer simulation model can be used synergistically and can lead to a better alternative method than methods restricted to only one of them. The outcome of our methods is a number of good system configurations, each of which is characterised by its cycle time (CT)–throughput (TH) profile. Such profiles fully describe the system's comprehensive performance over a wide range of demand scenarios (involving varying product mix), and hence can be used to thoroughly evaluate alternative configurations in capacity expansion decisions. 相似文献
1000.
Susan R. Sandeman Carol A. Howell Gary J. Phillips Yishan Zheng Guy Standen Robert Pletzenauer Andrew Davenport Kolitha Basnayake Owen Boyd Stephen Holt Sergey V. Mikhalovsky 《Journal of materials science. Materials in medicine》2014,25(6):1589-1597
Adsorbents designed with porosity which allows the removal of protein bound and high molecular weight uraemic toxins may improve the effectiveness of haemodialysis treatment of chronic kidney disease (CKD). A nanoporous activated carbon monolith prototype designed for direct blood contact was first assessed for its capacity to remove albumin bound marker toxins indoxyl sulphate (IS), p-cresyl sulphate (p-CS) and high molecular weight cytokine interleukin-6 in spiked healthy donor studies. Haemodialysis patient blood samples were then used to measure the presence of these markers in pre- and post-dialysis blood and their removal by adsorbent recirculation of post-dialysis blood samples. Nanopores (20–100 nm) were necessary for marker uraemic toxin removal during in vitro studies. Limited removal of IS and p-CS occurred during haemodialysis, whereas almost complete removal occurred following perfusion through the carbon monoliths suggesting a key role for such adsorbent therapies in CKD patient care. 相似文献