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801.
Cauchy with whale optimizer based eagle strategy for multi-level color hematology image segmentation
Ray Swarnajit Das Arunita Dhal Krishna Gopal Gálvez Jorge Naskar Prabir Kumar 《Neural computing & applications》2021,33(11):5917-5949
Neural Computing and Applications - Pathological color image segmentation is an exigent procedure due to the existence of imperceptibly correlated, and indistinct multiple regions of concern.... 相似文献
802.
The nature of carbidesvis-a-vis austenite grain growth characteristics in a ball-bearing steel (1Cr-1C) and in a wear-resistant steel (6Cr-1Mo-1C) is reported. Quantitative EPMA analysis was used to determine the type of carbides andin situ examination of austenite grain growth was carried out in a hot-stage microscope. The grain size against temperature plots indicated an initial stage of slower normal grain growth, followed by the abnormal growth, or, grain coarsening beyond a critical soaking temperature. The M3C type of carbides containing a small amount of chromium could inhibit grain coarsening up to 1223 K in 1Cr-1C steel, whereas the alloy carbides of the M7C3 type with a substantial amount (about 35 mass%) of chromium were more effective in restricting grain growth even up to 1273 K in the 6Cr-1Mo-1C steel. In addition, the grain sizes obtained in the latter steel were found to be considerably smaller than those of the former variety at all soaking temperatures investigated. 相似文献
803.
Kenneth R. Anderson David E. Coleman C. Ray Hill Andrew P. Jaworski Patrick L. Love Douglas A. Spindler Marwan Simaan 《Annals of Mathematics and Artificial Intelligence》1990,2(1-4):21-37
In this paper we discuss a set of software tools developed to support the tasks associated with managing special causes of variation in a manufacturing process. These tasks include the detection of significant changes in process variables, a diagnosis of the causes of those changes, the discovery of new causes, the management of performance data, and the reporting of results. The software tools include automatic recognition of out-of-control features in critical process variables, rule-based diagnosis of special causes, a model-based search for symptoms where a diagnosis is not possible, and automated reporting aids. It is hoped that these tools will enhance the efficiency of special cause management. 相似文献
804.
Electrical resistivity studies on several (Pd1–x
Au
x
)99.93Fe0.07 alloys between 25 mK and 1 K are reported. The experiments reveal interesting features of the impurity spin polarization with the addition of Au atoms to pure PdFe0.07 alloy. Forx<0.28 the ternary alloys exhibit a familiarT
2 dependence for belowT
c
, indicative of complex magnetic behavior. For still higher Au concentrations, resistivity maxima occur in these alloys, reflective of short-range magnetic ordering. Arguments are presented to show that this is strongly suggestive of spin-glass-type freezing at lower temperatures, as is observed in many canonical metallic spin-glasses. 相似文献
805.
An attempt was made to use high-melting lowdigestible fat palmstearin as a vanaspati substitute by blending it with polyunsaturated
fatty acid-rich liquid oils. This blending produced fat products of zero-trans fatty acid content and melting points below the human body temperature, so that they can be digested easily. The new blended
products were fed to male albino rats (Charles Foster strain); the coefficients of digestibilities were 94.2% for palmstearin
and rapeseed oil blend, 95.1% for palmstearin and sunflower oil blend, and 96.2% for palmstearin and soybean oil blend, which
were somewhat better than the digestibility coefficient of conventional vanaspati (93.6%). Feeding experiments for three months
showed comparable results in terms of serum lipid profiles. The blended products significantly increased the total cholesterol
level but not the free cholesterol level in serum and liver of rats when compared with those of the conventional vanaspati
group of rats. 相似文献
806.
M.A. Ray T. Tyler B. Hook A. Martin G. Cunningham O. Shenderova J.L. Davidson M. Howell W.P. Kang G. McGuire 《Diamond and Related Materials》2007,16(12):2087-2089
It was demonstrated that an atmospheric pressure dielectric barrier glow discharge system is a powerful tool for the surface functionalization of nano-crystalline diamond films. Diamond film functionalization was performed in minutes using plasma discharges generated with fluorine containing gases. The chemical bonds formed between reactive species generated in the plasma and diamond surface were confirmed by FTIR and XPS analysis. Following plasma treatment, XPS analysis revealed a high concentration of F on the diamond surface, nearly 50 atomic percent. FTIR analysis revealed the presence F-bands related to CF3 (CF2) stretching vibrations and symmetric and asymmetric CF2 vibrations. It was concluded that atmospheric pressure dielectric barrier glow discharge is a highly effective means to fluorinate diamond surfaces within a modest time. 相似文献
807.
The influence of Lewis number on stability and oscillations for stirred tanks, catalytic wires and gauzes, and catalyst particles is determined quantitatively. The mathematical structure is discussed and illustrated by example. Relaxation oscillations are found to be the natural asymptote to the bifurcating limit cycles as Le → 0. 相似文献
808.
Ray RD 《Applied ergonomics》1984,15(1):55-59
Many hot objects which may be touched or handled every day can cause either discomfort, pain or burning of the skin. The precise effect will depend on the Contact Temperature tC, an intermediate value between the hot object and the skin temperature. The value of tC varies with the material, and is governed by the Contact Coefficient b, a property of the material which has a wide range of values from metals to plastics. In the experiments with 48 female subjects, surface and contact temperatures for three materials were measured over a wide range, and subject reactions recorded on a five-point comfort scale. From the heat conduction theory outlined, and using the calculated values of b for the three materials, the predicted safe surface temperatures were determined. These predicted values were then compared with the observed temperatures and with those recommended in British Standards. 相似文献
809.
Marvin J. Schwedock Larry C. Windes W. Harmon Ray 《Chemical Engineering Communications》1989,78(1):45-71
Heterogeneous and pseudohomogeneous two-dimensional models are compared to steady state and dynamic experimental data from a packed bed reactor for the partial oxidation of methanol to formaldehyde over an iron oxide-molybdenum oxide catalyst. Highly effective parameter estimation software was used to fit selected model parameters to large sets of experimental data so as to obtain small residuals. Heat transfer parameters which were successful in matching data from experiments without reaction were not capable of fitting data from experiments with reaction, and it was necessary to increase the radial heat transfer for higher temperatures or reaction rates. Axial composition profile data was represented by estimating the preexponential factors and activation energy in a half-order redox rate expression for methanol oxidation. After some decline in catalyst activity, a time-varying axial catalyst activity profile was determined from the data. A redox-type rate expression for the oxidation of formaldehyde to carbon monoxide was proposed to fit the data. The dynamics of the reactor temperature profile were accurately represented by the model. The heterogeneous and pseudohomogeneous models gave similar results in fitting experimental data, although the parameters determined for the two models were somewhat different. 相似文献
810.
The Quasi-steady-state-approximation (QSSA) applied lo continuous stirred tank reactors (CSTR) is examined. The induction period is found to be somewhat longer and the error in the QSSA larger than for batch reactors. This error is usually insignificant except when CSTR conversions are low. An alternative approximation is proposed for this case. The errors in the QSSA are also illustrated for the well known cases of Enzyme and Free-Radical polymerization kinetics. 相似文献