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91.
Coimbatore S. Balasundaram Rajaram Chandramani Thillai Balakrishnan Konnaiyur K. Krishnamoorthy 《Journal of the science of food and agriculture》1977,28(7):598-601
A study to find out the effect of manuring and the frequency of cutting on the yield of leaf protein was conducted with four fodder grasses. The study revealed that Cenchrus glaucus was superior to the other grasses tried and it gave the maximum yield of dry matter and extractable protein. Farm yard manure at 10 tons/ha along with ammonium sulphate at 33 kg N/ha proved to be the best in giving the highest yield of dry matter and leaf protein. For all the grasses the maximum yield was found to range within the first three cuttings. 相似文献
92.
93.
Fluid catalytic cracking, a common secondary process employed in the petroleum industry, is used to convert heavier feedstocks into products such as liquefied Petroleum Gas (LPG), motor gasoline, diesel etc. The present study focuses on developing a three lump fraction kinetic model to estimate the yield of C5 up to 370°C cut (motor gasoline and middle distillates). A Micro Activity Test (MAT) apparatus was used to estimate the parameters in the kinetic model. The study is useful in evolving a procedure to simulate plant performance using experimental data obtained in the MAT apparatus for a particular catalyst and feedstock in terms of the product yield pattern. 相似文献
94.
95.
The performance of packed bed adiabatic gas absorbers has been analyzed using the enthalpy and material balance equations incorporating a new parameter, fr, defined as the fraction of the heat of absorption that is accounted for in the gas stream. An experimental programme to evaluate fr was carried out and the data correlated. It was found that fr was dependent on the thermo-physical properties and the hydrodynamic conditions. It is postulated that the mechanism by which this heat transfer occurs is by turbulence at the interface and by entrainment. 相似文献
96.
JD Balakrishnan 《Canadian Metallurgical Quarterly》1998,40(4):601-623
Operators' performance in a vigilance task is often assumed to depend on their choice of a detection criterion. When the signal rate is low this criterion is set high, causing the hit and false alarm rates to be low. With increasing time on task the criterion presumably tends to increase even further, thereby further decreasing the hit and false alarm rates. Virtually all of the empirical evidence for this simple interpretation is based on estimates of the bias measure beta from signal detection theory. In this article, I describe a new approach to studying decision making that does not require the technical assumptions of signal detection theory. The results of this new analysis suggest that the detection criterion is never biased toward either response, even when the signal rate is low and the time on task is long. Two modifications of the signal detection theory framework are considered to account for this seemingly paradoxical result. The first assumes that the signal rate affects the relative sizes of the variances of the information distributions; the second assumes that the signal rate affects the logic of the operator's stopping rule. Actual or potential applications of this research include the improved training and performance assessment of operators in areas such as product quality control, air traffic control, and medical and clinical diagnosis. 相似文献
97.
P. Ramachandran K. Naganathan K. Balakrishnan R. Srinivasan 《Journal of Applied Electrochemistry》1980,10(5):623-626
Lead alloys are widely used as anodes in electrowinning operations, for the recovery of metals such as zinc, copper and chromium. When lead alloys are used as such it takes a long time for the build up of a compact, adherent and protective lead dioxide film. During the initial period prior to the build up of the compact layer of lead dioxide, the rate of anodic dissolution is very high, leading to a decrease in the purity of the cathode deposit. In order to minimize the duration of the conditioning of the anode, it is customary to build up a compact lead dioxide layer by pretreating the anodes in suitable electrolytes. An attempt is made to evaluate the performance of the pretreated electrodes by potentiodynamic methods. 相似文献
98.
Thapar B. Gerez V. Balakrishnan A. Blank D.A. 《Power Delivery, IEEE Transactions on》1991,6(2):601-607
A large number of grounding grids in substations have shapes other than a square or a rectangle, whereas the simplified formulas for mesh and step voltages available in the literature are derived for square or rectangular grids. Improvements in the simplified equations for determining mesh and step voltages are presented. With the modified simple equations, mesh and step voltages at a substation of any practical shape can be estimated with reasonable accuracy. The results obtained with the improved equations have been compared with accurate results obtained via computer. The error in the values obtained with the derived equations is within 16% for mesh voltage and less than 30% for step voltage 相似文献
99.
A. Bansal A. Schubert M. V. Balakrishnan M. Kumosa 《Composites Science and Technology》1995,55(4):375-389
Composite insulators are rapidly replacing their porcelain counterparts in electrical substation applications. These insulators consist of a glass-reinforced polymer (GRP) rod, with two metal end fittings radially crimped onto the ends of the rod during assembly. In this paper, axisymmetric finite element models are developed to evaluate the mechanical performance of composite insulators under externally applied axial compression. The analyses are performed by assuming both a perfectly bonded interface between the composite rod and the end fittings, and an imperfect interface which permits large relative sliding with Coulomb friction. Results indicate that the perfect interface model is unrealistic since it predicts singular stresses at the interface comer and an overall linear structural response. On the other hand, the imperfect interface model is found to simulate accurately the structural non-linearity caused by relative sliding of the GRP rod within the end fittings. The imperfect interface model has therefore been used to evaluate the effects of interface friction, and the extent of crimping, on the maximum load-bearing capacity of substation composite insulators. 相似文献
100.