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51.
52.
Kester Bruce E. Gilliland J. L. Fritts Stewart S. Bell Zeb G. Smith Hubert Berby Richard H. 《Industry Applications, IEEE Transactions on》1972,(1):8-18
MAN is but a part of the universe; his capabilities make him a significant link, in the cycle of life. To ensure this life, man must live in harmony with his environment. Recently, a disharmony has been discovered which could have grave effects upon the existence of man. It appears that man in his great thrust forward is destroying his own environment. The gravity of this threat to man's own existence carries some intrinsic problems of its own: man must allow his reason rather than his emotion to take command. 相似文献
53.
Smith Robert El. Wekstein David R. Sullivan Robert H. 《IEEE transactions on bio-medical engineering》1970,(2):151-156
A multiplexing, demodulating, and recording telemetry system designed to process multiple pulse-coded temperature channels is described. The system provides complete control of recording and multiplexing sequences and timing, and gives a single analog signal in response to each sample of pulse-coded data. It identifies all channels and indicates to a computer when a new data sample is to be processed. The system is self-calibrating to maintain accuracy over extended data collection periods, and is inexpensive. 相似文献
54.
55.
Electroantennograms (EAGs) from male and femaleIps avulsus, I. calligraphus, andI. grandicollis to their pheromones and selected host odorants or kairomones verified the presence of antennal olfactory receptors in both sexes of each species capable of detecting ipsdienol, ipsenol,cis- andtrans-verbenol,endo-brevicomin -pinene, frontalin, and verbenone. Each species possesses receptors with lower thresholds and in greater abundance for the compounds they produce and to which they are behaviorally most responsive. Detection of bothIps andDendroctonus pheromones by the three cohabiting species provides a sensory basis for olfactory interactions among the species. Differences in both threshold and saturation levels for EAGs for the various behavioral chemicals could denote differences in specific behavioral roles for each compound.Texas Agricultural Experiment Station Paper Number TA-22463. This research was supported in part by McIntire-Stennis Project 1525, USDA-CR grants 85-CRCR-1-1856 and 86-CRCR-2019 and NATO Collaborative Research Grant 86-0710. The findings, opinions, and recommendations expressed herein are those of the authors and not necessarily those of the U.S. Department of Agriculture. All programs and information of the Texas Agricultural Experiment Station are available without regard to race, ethnic origin, religion, sex, or age.Mention of a trademark, proprietary product, or vendor does not constitute a guarantee or warranty of the product by the U.S. Department of Agriculture and does not imply its approval to the exclusion of other products or vendors that may also be suitable. 相似文献
56.
The study of a three-phase catalytic slurry reactor for SO2 oxidation on activated carbon has been conducted with a dynamic response technique. The analysis of zero and first temporal moments of the gas for temperatures between 10 and 26°C provides individual measurements of the adsorption, desorption and surface reaction rate constants and their energies of activation. A parallel first-moment analysis was carried out for O2 adsorption onto carbon to obtain the necessary equilibrium constants for temperatures used in the SO2-oxidation calculations. With second moment analysis of adsorption data, we find the adsorption kinetic constants with and without reaction are in quantitative agreement. By evaluating the separate temperatu effect on the adsorption/desorption, and surface reaction rates, we conclude that neither step is controlling at temperatures up to 26°C. The values the several kinetic and equilibrium constants agree well with those found by other authors. 相似文献
57.
Naguib-Mostafa A. Smith A. K. deMan J. M. 《Journal of the American Oil Chemists' Society》1985,62(4):760-762
Journal of the American Oil Chemists' Society - Scanning electron microscopy was used to study the crystal structure of hydrogenated Canola oil. Fixation of the samples was carried out at 10 C... 相似文献
58.
J. K. Weil F. D. Smith A. J. Stirton R. G. Bistline 《Journal of the American Oil Chemists' Society》1963,40(10):538-541
Even chain sodium alkanesulfonates from the Strecker reaction, odd chain sodium alkanesulfonates from the alkaline decarboxylation
of α-sulfo acids, and sodium 1-hydroxy-2-alkanesulfonates from the reduction of esters of α-sulfo acids were compared with
respect to Krafft point, critical micelle concentration, detergency and foam height. Sodium alkanesulfonates and crude fusion
products from the α-sulfo acids (mixtures of alkanesulfonates of one less carbon atom with a lesser amount of a soap of two
less carbon atoms) are more soluble and have better detergent and foaming properties. Sodium 1-hydroxy-2-alkanesulfonates
resemble monosodium salts of α-sulfo acids.
Alkanesulfonic acids and 1-hydroxy-2-alkane-sulfonic acids obtained from the sodium salts by ion exchange have lower Krafft
points and are more readily soluble. The critical micelle concentrations of 1-hydroxy-2-alkanesulfonic acids and α-sulfo acids
are nearly the same and about equal to those of alkanesulfonic acids of one less carbon atom.
Presented at the AOCS meeting in Toronto, Canada, 1962.
A laboratory of the E. Utiliz. Res. & Dev. Div., ARS, U.S.D.A. 相似文献
59.
L. Smith 《Chemical engineering science》2004,59(15):3223-3234
We demonstrate the enhanced capacities of our analysis toolset for three-dimensional data. In particular, we provide supporting evidence for some of the conclusions reached in our previous studies of two-dimensional avalanching heaps. Segregation by self-diffusion is shown to take place in three-dimensional assemblies and self-diffusion velocities are shown to be of a comparable order of magnitude to those found in plane-strain situations. The effect on assembly evolution by discrete avalanching of the availability of a third dimension for translation is investigated. The discrete wavelet transform is again shown to be a useful component of the toolset in coupling process variables in the context of the discrete defining events associated with assembly evolution. In particular, we move towards the determination of time constants by correlating wavelet coefficients with a time shift. 相似文献
60.
These investigations are concerned with water-polymer interactions in polymer latices. It is known that water can act as a plasticizer for many solid polymers and cause a reduction in the glass transition temperature, Tg, of the amorphous regions. Experiments were carried out to determine whether pulsed n.m.r. techniques could be used to study the Tg of a polymer suspension and hence the influence of water and electrolyte on it. From T1 and T2 proton relaxation measurements as a function of temperature on polystyrene latex systems it was shown that the presence of water lowers the Tg of the polymer particles (by about 10°C), the effect being slightly greater in the presence of concentrated electrolyte. The extent of electrolyte penetration into the particles was deduced by studying relaxation as a function of particle diameter in latices containing paramagnetic Mn2+ ions. Using simple theories of relaxation and spin diffusion it was concluded that for all but the smallest particles electrolyte penetration is restricted to a very thin shell of the order of 1 nm. These conclusions were supported by the results of similar measurements on PTFE particles. 相似文献