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91.
The ability to handle very large amounts of image data is important for image analysis, indexing and retrieval applications. Sadly, in the literature, scalability aspects are often ignored or glanced over, especially with respect to the intricacies of actual implementation details. In this paper we present a case-study showing how a standard bag-of-visual-words image indexing pipeline can be scaled across a distributed cluster of machines. In order to achieve scalability, we investigate the optimal combination of hybridisations of the MapReduce distributed computational framework which allows the components of the analysis and indexing pipeline to be effectively mapped and run on modern server hardware. We then demonstrate the scalability of the approach practically with a set of image analysis and indexing tools built on top of the Apache Hadoop MapReduce framework. The tools used for our experiments are freely available as open-source software, and the paper fully describes the nuances of their implementation.  相似文献   
92.
In this paper, stochastic optimal strategy for unknown linear discrete‐time system quadratic zero‐sum games in input‐output form with communication imperfections such as network‐induced delays and packet losses, otherwise referred to as networked control system (NCS) zero‐sum games, relating to the H optimal control problem is solved in a forward‐in‐time manner. First, the linear discrete‐time zero sum state space representation is transformed into a linear NCS in the state space form after incorporating random delays and packet losses and then into the input‐output form. Subsequently, the stochastic optimal approach, referred to as adaptive dynamic programming (ADP), is introduced which estimates the cost or value function to solve the infinite horizon optimal regulation of unknown linear NCS quadratic zero‐sum games in the presence of communication imperfections. The optimal control and worst case disturbance inputs are derived based on the estimated value function in the absence of state measurements. An update law for tuning the unknown parameters of the value function estimator is derived and Lyapunov theory is used to show that all signals are asymptotically stable (AS) and that the estimated control and disturbance signals converge to optimal control and worst case disturbances, respectively. Simulation results are included to verify the theoretical claims.  相似文献   
93.
An investigation has been performed of the cell nucleation and initial growth behaviors in the foam processing of polypropylene (PP) in both the linear and branched forms. These materials were foamed in extrusion with the two blowing agents, CO2 and isopentane. The cell density generally increased with an increased content of the blowing agent, for both CO2 and isopentane. The effect of processing pressure on the cell density was distinct when CO2 was used, whereas no pressure effect was observed in the foam processing with isopentane. The cell morphologies for the two PPs were found to be significantly different. A slightly lower nuclei density was observed in the branched PP foams than in the linear PP foams. However, the phenomenon of cell coalescence was observed much less in the branched PP foams. Most cells in the branched PP foams were closed, whereas in the linear PP foams they were connected to each other. The experimental results indicated that the branched structure played an important role in determining the cell morphologies through its effects on the melt strength and/or melt elasticity.  相似文献   
94.
The in vitro incorporation of leucine, isoleucine and pyruvate into lipids was compared and the possibility that leucine might serve as anin situ precursor to the correspondingiso fatty acids in the rat sciatic nerve was studied. The relative incorporation of14C from leucine into lipids vs. nonlipids was 20%, and the incorporation of label into total lipids from leucine was one-half that from pyruvate. The incorporation of label from leucine and pyruvate into sterols was nearly equivalent, but the incorporation of label into all other lipid classes from leucine was less than that from pyruvate, and the incorporation of label from isoleucine into lipids was much less in all cases. No detectable label from leucine was incorporated into brached chain fatty acids. It is concluded that leucine may be a substantial in vitro precursor to all major lipids in peripheral nerve, especially sterols. The possibility and significance of a leucine catabolic pathway in the cytosol in relation to availability of 3-hydroxy-3-methylglutaryl CoA for sterol biosynthesis is discussed.  相似文献   
95.
Dogs were maintainedoon a control ration or on a semisynthetic diet, containing 5% cholesterol and 16% hydrogenated coconut oil, known to induce hyperlipemia and arteriosclerosis. Circulating leukocytes isolated from dogs fed the coconut oil containing diet were shown to incorporate 50% more radioactivity into lipids than control leukocytes when incubated with acetate-1-14C. This increase, expressed as dpm/mg of leukocyte DNA, was not specific for any particular lipid since the distribution of radioactivity between neutral lipids and phospholipids, as well as among their subfractions, was the same regardless of the diet fed. The labeling patterns observed suggest that leukocyte fatty acid synthesis from acetate occurs predominantly, and perhaps exclusively, by the chain elongation pathway.  相似文献   
96.
A member of the new series of cationic reactive dyes containing a thioether‐ethylsulphone grouping referred to in Part 1 of this series has been applied to nylon at pH 3–10. The dye is water soluble and shows excellent substantivity for nylon 6.6 when dyed at the boil at pH 8–10. Under alkaline conditions, gradual β‐elimination back to the vinylsulphone dye occurs and covalent bond formation quickly takes place with the fibre; the higher the pH the more rapidly this occurs. Dyeings carried out at pH 10 showed very good brightness and levelling, together with good wash fastness. The light fastness of dyeings at moderate depth was 4–5 on the Blue Wool scale.  相似文献   
97.
Mullite-SiC-whisker composites were prepared by powder processing using two commercial SiC whiskers. These composites were prepared by sintering rather than hot-pressing. A mulliteSlC-powder composite and a base line mallite material were also prepared for comparison with the two whisker composite materials. Fracture toughness measurements showed significant enhancement in only one of the whisker composite materials. The microstructure of the four materials was examined by scanning electron microscopy and transmission electron microscopy to assist in the explanation of the mechanical behavior of these composites. The examinations suggested that most of the toughening results from second-phase particles, with only limited toughening from effects associated with whiskers per se. In one case, higher toughness was partially associated with the formation of sialon phase by reaction with the whiskers and the furnace environment.  相似文献   
98.
Compressive strength and hydration characteristics of wastepaper sludge ash-ground granulated blastfurnace slag (WSA-GGBS) blended pastes were investigated at a water to binder (w/b) ratio of 0.5. The strength results are compared to those of normal Portland cement (PC) paste and relative strengths are reported. Early relative strengths (1 day) of WSA-GGBS pastes were very low but a marked gain in relative strength occurred between 1 and 7 days and this increased further after 28 and 90 days. For the 50% WSA-50% GGBS blended paste, the strength achieved at 90 days was nearly 50% of that of the PC control paste. Transmission electron microscopy (TEM), X-ray diffraction (XRD) and thermogravimetric (TG) analysis were carried out to identify the mineral components in the WSA and the hydration products of WSA and WSA-GGBS pastes. The principal crystalline components in the WSA are gehlenite, calcium oxide, bredigite and α′-C2S (stabilised with Al and Mg) together with small amounts of anorthite and calcium carbonate and traces of calcium hydroxide and quartz. The α′-C2S and bredigite, which phase separate from liquid phase that forms a glass on cooling, are difficult to distinguish by XRD. The hydration products identified in WSA paste are CH, C4AH13, C3A.0.5CC?.0.5CH.H11.5 and C-S-H gel plus possible evidence of small amounts of C2ASH8 and C3A.3CS?.H32. Based upon the findings, a hydration mechanism is presented, and a model is proposed to explain the observed strength development.  相似文献   
99.
Wool fabrics undergo setting during dyeing. The degree of set can be controlled by careful selection of dyebath conditions and also by the addition to the dyebath of chemicals termed anti-setting agents. The anti-setting effect of sodium thiocyanate has been evaluated according to its concentration in the dyebath and the dyebath pH. The fabric crease-angle method was adopted to estimate the degree of anti-setting. In the case of wool fabric boiled in the presence of sodium thiocyanate, good anti-setting effects resulted from the pH 3 and pH 5 treatment baths. Chemical changes in the wool were detected using FTIR analysis.  相似文献   
100.
Dyeing cotton with reactive dyes under neutral conditions   总被引:1,自引:0,他引:1  
This paper describes a new method to dye cotton with selected reactive dyes by long-liquor – or so-called 'exhaustion'– processes under neutral conditions. Particularly promising results were obtained with reactive dyes containing free vinyl sulphone residues. Although there are dyes on the market that contain free vinyl sulphone groups, for example, the Novacron C (Huntsman) range of dyes, many of this class contain 'blocked' vinyl sulphone residues; examples include sulphatoethylsulphone or chloroethylsulphone precursor groups, and these may be preactivated to the highly reactive vinyl sulphone form simply by a mild alkali treatment. After this activation, neutral, long-liquor dyeings can be carried out at the boil in the presence of electrolyte. This new dyeing method gave very good results in terms of overall fixation efficiency values, without the need for alkali additions.  相似文献   
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