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991.
Cholesteryl ester hydrolase (CEH), triacylglycerol lipase (TGL) and retinyl palmitate hydrolase (RPH) were measured in 104,000
×g supernatants from rat liver under optimal conditions for measurement of cytosolic CEH. Similar levels of hydrolytic activity
were seen with oil droplet dispersions of cholesteryl oleate, trioleoylglycerol and retinyl palmitate. No cytosolic TGL activity
was seen with substrate presented in the triton-albumin emulsion used for measurement of lipoprotein lipase-like TGL associated
with hepatic plasma membrane. Cytosolic CEH, TGL and RPH were differentially partially purified by both ammonium sulfate precipitation
and anion exchange fast protein liquid chromatography (FPLC). Of the three activities, only CEH was stimulated by cholestyramine
feeding and by activators of protein kinases A and C. All three activities were inhibited by alkaline phosphatase treatment,
although to different degrees. It is concluded that these activities are catalyzed by at least three differentially regulated
enzymes with a high degree of specificity for their respective substrates. 相似文献
992.
Raw, dewaxed and oxidized jute fibres and those chemically modified with phenol and formaldehyde (treatment done for 3 h at 95° C and pH 8) before or subsequent to oxidation, were subjected to graft copolymerization with methyl methacrylate (MMA) in the presence or absence of some other monomers such as maleic anhydride (MA) or methacrylic acid (MAA) in limited aqueous system using K2S2O8 as the initiator under photoconditions with the objective of inducing improved rot resistance and dyeability without loss in tensile strength of the fibre. For preparing oxy-jute, dewaxed and preswollen (dewaxed jute fibre swollen with 10% aqueous urea at 90° C for 2h) jute fibre were separately subjected to mild oxidation or bleaching using aqueous H2O2 and NalO4 and non-aqueous chlorine (Cl2 in CCl4) under specified conditions. Optimum conditions for graft copolymerization have been established by examination of the effect of such variables as monomer concentration, time of polymerization and nature of chemical modification of jute fibre prior to vinyl grafting. Percentage grafting, tenacity (g denier–1), dye fixation (%) and rot resistance (expressed as percentage retention of tensile strength of the fibre after a standard soil burial test) were evaluated and analysed. High rot resistance (80–90% retention of tensile strength after soil burial test) and dye fixation (%) of as high as 86% were readily obtained for grafted jute fibres. Washing fastness and light fastness properties of the dyed fibres (grafted and ungrafted) were also examined and compared. 相似文献
993.
J.N. Mohapatra A.K. Panda M.K. Gunjan N.R. Bandyopadhyay A. Mitra R.N. Ghosh 《NDT & E International》2007,40(2):173-178
Magnetic hysteresis loop and Barkhausen emissions were recorded and analysed for 5Cr–0.5Mo steel after ageing at 600 °C for various lengths of time. At the initial stage of ageing the interstitial carbon diffuses towards the grain boundary making the matrix magnetically softer. During this stage, extending up to 200 h of ageing, magnetic softness was found to be increasing. This was associated with a decrease in coercivity and increase in Barkhausen voltage. Beyond 200 h of ageing the precipitation of alloy carbides attain subsequent growth, making the material magnetically harder. The evolution of carbides was studied using SEM-EDAX analysis. It was observed that most of the carbides transformed into M23C6 type after ageing for 400 h. 相似文献
994.
Citro R. Ghosh S. Churgin P.G. 《IEEE transactions on information technology in biomedicine》1997,1(3):189-204
The concept of continuity in medicine is fundamental and it refers to the delivery of medical care to a patient by a care provider in an uninterrupted and coordinated manner and in accordance with the medical care needs of the patient. This paper models continuity for a representative staff model health maintenance organization (HMO) clinic in suburban Arizona and simulates patient visits that are stochastically generated through utilizing representative numbers of patient visits and care providers. It focuses on individual-based continuity delivered by a primary care provider, i.e., a general practitioner. In the simulation, the visit patterns of patients, their ages, and the length of the interaction episodes are synthesized stochastically. The distributions reflect both the patient visit profile, by age, inherent in the 90000+ patient electronic records collected at the CIGNA HMO clinic at Chandler, AZ, over a three-year period, and the population distribution inherent in the CIGNA records. This paper proposes a new definition of continuity, fundamental continuity of care index (FCCI), and argues that, fundamentally, a primary care provider's depth of understanding of the patient is directly proportional to the total length of interaction between the patient and the primary care provider 相似文献
995.
The paper presents a simple and effective method for the concurrent manipulation of linearly ordered data structures on hypercube systems. The method Is based on the existence of an augmented binomial search tree, called the pruned binomial tree, rooted at any arbitrary processor node of the hypercube such that; every edge of the tree corresponds to a direct link between a pair of hypercube nodes; and the tree spans any arbitrary sequence of n consecutive nodes containing the root, using a fanout of at most [log2 n] and a depth of at most [log2 n]+1. Search trees spanning nonoverlapping processor lists are formed using only local information, and can be used concurrently without contention problems. Thus, they can be used for performing operations such as broadcast and merge simultaneously on sets with nonuniform sizes. Extensions of the tree to k-ary n-cubes and faulty hypercubes are presented. Applications of this concurrent data structure to low- and intermediate-level image processing algorithms, and for dictionary operations involving multiple keys, are also outlined 相似文献
996.
997.
A set of self-consistent thermodynamic model parameters is presented to describe the phase equilibria of the Ag-Pd, Co-Pd, Fe-Pd, and Ni-Pd systems. In most cases, the calculated values using the optimized model parameters agree very well with the experimental data. The FePd and FePd3 phases with large homogeneity ranges are described by the compound energy formalism. At present, insufficient thermodynamic data are available for these two phases. Therefore, experimental data on the heat of formation and/or the first-principle calculation of cohesive energies will be very useful for further refinement of thermodynamic parameters of FePd and FePd3 phases. 相似文献
998.
Influence of cocatalyst on the stereoselectivity and productivity of styrene polymerization reactions 总被引:1,自引:1,他引:0
Sutapa Ghosh 《Journal of Polymer Research》2009,16(2):117-124
Influence of different cocatalysts on the polymerization reaction of styrene using heterogeneous nanoparticle NA-MgO and NA-TiO2
(anatase) supported bis (cyclopentadienyl) zirconium dichloride catalysts is studied. Methyaluminoxane, trityl tetrakis(pentafluorophenyl)borate(1),
dimethylanilinium tetrakis (pentafluoro-phenyl)borate (2) and tris(pentafluorophenyl)borane (3) are used as cocatalysts for
this study. The productivity and stereoselectivity of the catalysts systems are found to be highest with MAO and lowest with
the borane 3 (MAO > 1> 2 > 3). Catalysts derived from the borane 3 yield amorphous atactic polystyrenes but those from cocatalysts
MAO, 1, or 2 yield crystalline, syndiotactic polystyrenes under the same reaction conditions. Effects of addition of various
scavengers and solvents with different polarities on styrene polymerizations are also reported here. Characterization of the
obtained polymers is done by Gel Permeation Chromatography, 13C-NMR spectroscopy and Differential Scanning Calorimetry. 相似文献
999.
Srivaths Ravi Indradeep Ghosh Rabindra K. Roy Sujit Dey 《Journal of Electronic Testing》1998,13(2):201-212
In this paper, we propose a controller resynthesis technique to enhance the testability of register-transfer level (RTL) controller/data path circuits. Our technique exploits the fact that the control signals in an RTL implementation are don't cares under certain states/conditions. We make an effective use of the don't care information in the controller specification to improve the overall testability (better fault coverage and shorter test generation time). If the don't care information in the controller specification leaves little scope for respecification, we add control vectors to the controller to enhance the testability. Experimental results with example benchmarks show an average increase in testability of 9% with a 3–4 fold decrease in test generation time for the modified implementation. The area, delay and power overheads incurred for testability are very low. The average area overhead is 0.4%, and the average power overhead is 4.6%. There was no delay overhead due to this technique in most of the cases. 相似文献
1000.
S Ghosh 《Canadian Metallurgical Quarterly》1998,111(1064):151-152