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971.
With the aid of a computer graphic display technique, data gathered from exploratory diencephalic recordings in 130 stereotactic operative procedures are presented to show the location and somatotopography of 'pressure'-evoked cellular responses. In addition, the variable position of these responses in relation to common diencephalic landmarks is presented. Our findings indicate that response points are more compact when related to a common posterior commissure (PC) and lie in a sickle-shaped zone 14-16 mm lateral to the midline and 2-8 mm rostral to anatomically the nucleus ventralis caudalis or the nucleus ventralis intermedius. Somatotopographically, face responses were medial to the leg. 相似文献
972.
973.
Guy A. Dumont 《Automatica》1982,18(3):307-314
On a chip refiner the gain of the transfer function between the refiner motor load and the plate gap is subject to a slow drift due to plate wear and to sudden changes in sign due to collapse of the pulp pad. A self-tuning regulator was designed to control motor load by manipulating the plate gap. It uses a recursive least-squares estimator with a variable forgetting factor in conjunction with a Dahlin regulator. Results of plant trials on an industrial thermomechanical pulp production unit show that this regulator is capable of tracking the slow gain drift and of taking proper action in case a pulp pad collapse occurs. 相似文献
974.
Neil A. Macleod Patrick Butz John P. Simons Guy H. Grant Christopher M. Baker George E. Tranter 《Israel journal of chemistry》2004,44(1-3):27-36
The sensitivity of the electronic circular dichroism (ECD) of a chiral molecule to structural and environmental changes has been investigated using 1-(R)-phenylethanol (1-PE) as the benchmark solute and cyclohexane and water as the trial solvents. Rotatory strengths associated with the π → π* (1Lb) electronic transition have been calculated ab initio for: (a) isolated 1-PE, as a function of the dihedral angles within its chiral side chain and between the side chain and the aromatic ring: these confirm the validity of the empirical “sector rule” but with the signs reversed; (b) the singly and doubly hydrated clusters of 1-PE, isolated in the gas phase; (c) 1-PE and its singly and doubly hydrated clusters embedded in a polarizable dielectric continuum; and (d) 1-PE in an aqueous solution interacting with the local hydration shell and with the polarizable dielectric continuum, using averaged solute structures computed from the fluctuating solute and solvent configurations generated via molecular dynamics simulations. The ab initio calculations (conducted with GAUSSIAN 98) employed configuration interaction singles (CIS) or time-dependent density functional theory (TD-DFT) procedures using basis sets of double- and triple-zeta quality. The results have been related to experimental observations and discussed in terms of changes in the molecular geometry and solvent-induced perturbations. 相似文献
975.
The experimental study of the H2S sulfidation of a Fe-22Cr-5.5 Al alloy, which leads to a multilayered scale, points out the existence of a critical temperature and a long time evolution of the layered scale. A detailed analysis of the experimental data shows that this could be explained by a kinetic approach involving non-linear processes. 相似文献
976.
Oliver Guy Stefanovic Victor R. April Georges-Emile 《Industry Applications, IEEE Transactions on》1983,(1):105-112
Three different phase-commutation thyristor bridges are applied to slip-power control of an induction motor. The performance of the drive is experimentally evaluated for each thyristor bridge with respect to input power factor, efficiency, total. input current, size of the dc-link inductor, and regulation. The best results are obtained with the eight-thyristor bridge while the conventional six-thyristor converter offers the worst overall performance. 相似文献
977.
978.
Guy Muller 《Polymer Bulletin》1981,5(1):31-37
979.
Ultrafiltrable serum uric acid (u.a.) was determined by ultrafiltration under in vivo conditions in humans using a reliable technique described in detail. It could be demonstrated that u.a. binding to macromolecules occurs in healthy humans (controls) and in patients with renal calcium stones. The percentage of free u.a. in controls (n=60) averages 86.2 +/- 0.9 SEM. With increasing age, bound u.a. rises slightly. On the other hand, younger (less than 40 years) stone patients have significantly more bound u.a. than matched controls (80.7 +/- 1.0 SEM; p less than 0.001), whereas this is not found in elderly patients. The degree of binding is not related to concentration of plasma proteins but inversely related to free fatty acid concentration in healthy controls (r= -0.52; p less than 0.01). It is suggested that no augmentation of tubular u.a. filtered by the glomeruli could have occurred. The origin of fasting hyperuricosuria shown earlier to be a prominent feature of young renal calcium stone formers is yet unknown. 相似文献
980.
A. G. Guy M. Golomb A. S. Yue 《JOM Journal of the Minerals, Metals and Materials Society》1957,9(10):1204-1206
Standard methods are available for calculating the results of diffusion processes providing the diffusion coefficient is a constant. In fact, the diffusion coefficient changes radically with composition in most alloy systems and therefore the standard methods are not quantitatively applicable. It is shown that a correction can be made for the variation of the diffusion coefficient with concentration by employing a special coordinate transformation. Illustrative calculations for two types of variation of the diffusion coefficient with concentration show that the accuracy of this approximate method is of the order of 20 pct for large changes in the diffusion coefficient. The relation of the present method to that of Wagner is discussed. 相似文献