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91.
Sato K  Yamamoto S  Kamada O  Ochi M 《Applied optics》1984,23(23):4450-4452
A method of measuring angular displacement is investigated that uses two pairs of photodiode arrays arranged in a square and crossed linear images produced with two cylindrical mirrors. According to this method the measurement error can be greatly reduced even when inclination of the rotation axis exists.  相似文献   
92.
We propose a method for a sign language animation by skin region detection applied to an infrared thermal image. In a system incorporating the proposed method, a 3D CG model corresponding to a person’s characteristic posture while using sign language is generated automatically by pattern recognition of the thermal image, and then a person’s hand in the CG model is set. The hand part is made manually beforehand. If necessary, the model can be replaced manually by a more appropriate model corresponding to training key frames, and/or the same generated model can be refined manually. In our experiments, three hearing-impaired people, who were experienced in using sign language, recognized the Japanese sign language gestures of 70 words expressed as animations with 94.3% accuracy. We further improved the system by correcting the position and direction of the hand of the automatically generated model through the use of a fuzzy algorithm and simulated annealing.  相似文献   
93.
A method of stress analysis for a two dimensional crack, which is subjected to internal gas pressure, and situated parallel to a free surface of a material, is presented. It is based on the concept of continuously distributed edge dislocations of two kinds, i.e. one with Burgers vector normal to the free surface and the other with Burgers vector parallel to it.Stress fields of individual dislocations are chosen so as to satisfy stress free boundary conditions at the free surface, by taking account of image dislocations. Distributions of both kinds of dislocations in the crack are derived so as to give the internal gas pressure and, at the same time, to satisfy shear stress free boundary conditions on the crack surface. Stress fields xx, yy and xy in the sub-surface layer are then determined from them. They have square root singularities at the crack-up.
Résumé On présente un méthode d'analyse de contrainte dans le cas d'une fissure bidimensionnelle soumise à la pression d'un gaz interne et située parallèlement à une surface libre d'un matériau. La méthode est basée sur un concept de dislocation-coin distribuée de manière continue et de deux types, c'est-à-dire l'une présentant un vecteur de Burgers normal à la surface libre et l'autre comportant un vecteur de Burgers parallèle à cette surface libre.On choisit le champ de contrainte de dislocations individuelles de telle manière qu'il satisfasse à des conditions de frontières libres de contrainte à la surface libre et en tenant compte des dislocations images. On en tire les distributions des deux types de dislocation dans la fissure de manière à fournir la pression interne des gaz et, dans le même temps, à satisfaire les conditions d'absence de contraintes de cisaillement aux frontières, sur la surface de la fissure. On en détermine les champs de contrainte et dans la couche subsuperficielle. Ces champs présentent des singularités d'ordre 1/2 à la face supérieure de la fissure.
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94.
Changes of magnetic minor hysteresis loops in pure Fe, Fe-1 wt% Mn, Fe-0.9 wt% Cu, and Fe-0.9 wt% Cu-1 wt% Mn model alloys after neutron irradiation have been studied. Minor-loop coefficients which are obtained from scaling relations between minor-loop parameters and in proportion to internal stress, were found to decrease in all model alloys after the irradiation to a fluence of 3.32 × 1019 n cm−2. The decrease of the coefficients is larger for alloys including Cu and is enhanced by 1 wt% Mn addition. Such decrease implying the reduction of internal stress during irradiation is in contrast with changes of yield strength after the irradiation that increase with Cu and Mn contents. A qualitative explanation was given on the basis of the preferential formation of Cu precipitates along pre-existing dislocations which reduces internal stress of the dislocations.  相似文献   
95.
Δ5 Desaturase-defective mutants of an arachidonic acid-producing fungus, Mortierella alpina 1S-4, accumulate large amounts of 8,11,14,17-cis-eicosatetraenoic acid (20:4ω3) when grown with linseed oil. One of the mutants, the S14 strain, produced 1.65 mg of 20:4ω3 per mL of culture medium (corresponding to 66.0 mg/g dry mycelia and 11.6% of total cellular fatty acids) when grown in a medium containing 1% glucose, 1% yeast extract, and 4% linseed oil methyl ester at 28°C for 2 d, and then at 16°C for 7 d. In a bench-scale fermentation in a 5-L jar fermenter, 20:4ω3 production reached 1.60 g/L of culture medium on the eighth day (corresponding to 77.3 mg/g dry mycelia and 26.0% of total cellular fatty acids). The cellular lipids of the S14 strain comprised 75.8% triacylglycerol (TG), 6.7% diacylglycerol, and 13.3% phospholipids (PL). The percentage of 20:4ω3 was higher in PL than in TG, and highest in phosphatidylcholine (32.6%).  相似文献   
96.
The influence of Joule heating treatments and carbon black (CB) on the electrical and thermal behavior of epoxy resin composites is well described in this article. The effect of CB and Joule heating on network structure characteristics, such as shrinkability, interparticle distance between conductive particles, crosslinking density, hardness, thermoelectric power, thermal conductivity, the thermal expansion coefficient, and scanning electron microscopy, of epoxy composites was investigated. The electrical conductivity (σ) of epoxy resin correlated with the volume fraction of CB and Joule heating treatment. σ increased continuously with increasing CB content, and Joule heating increased the level of σ, which makes it attractive for electronic utilization. The σ for fresh and Joule heating samples was recorded during heating–cooling cycles. The conduction mechanism of σ for epoxy composites was identified. The activation energy and hopping energy for two batches of epoxy as a function of CB content were estimated. The hopping distance, the state density at the Fermi level, and the radius of localized wave function versus CB content were evaluated. The current–voltage–temperature characteristics of fresh and Joule heating samples of epoxy composites were demonstrated. The thermal reliability was tested by means of temperature–time characteristics when certain applied power was on and off for several cycles. The specific heat and amount of heat transfer by radiation and convection were calculated based on the energy balance model for two batches. The results indicate that the Joule heating effect is a very effective and prospective way of enhancing the electrical and thermal stability of epoxy–CB composites for consumer use as heaters and in other electronic areas such as electromagnetic shielding effectiveness. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 87: 97–109, 2003  相似文献   
97.
A Δ5 and Δ12 desaturase-defective mutant of an arachidonic acid-producing fungus, Mortierella alpina 1S-4, produced 8,11,14,17-cis-eicosatetraenoic acid (20:4ω3) intracellularly when grown with linseed oil. Dihomo-γ-linolenic acid was the only C20 polyunsaturated fatty acid (4.9 wt% of total mycelial fatty acids) other than 20:4ω3. AA and 5,8,11,14,17-cis-eicosapentaenoic acid were not detected. The mycelial lipids consisted of 82.2% (by mol) triacylglycerol (TG), 7.1% diacylglycerol, 8.9% phospholipids (PL), and 1.9% free fatty acids. The percentage of 20:4ω3 was higher in PL (30.1%) than in TG (11.6%), and highest in phosphatidylcholine (38.9%). Under the optimal conditions with a 5-L jar fermenter, 20:4ω3 production amounted to 97.4 mg/g dry mycelia with a mycelial yield of 23 g/L on the twelfth day (corresponding to 2.24 g/L medium and 37.1% of total mycelial fatty acids).  相似文献   
98.
This paper describes the realization of a video encoder/decoder chip set for the consumer use digital video cassette recorder (VCR). The two chips with a 5 Mb external DRAM either encode the CCIR601 digital component video signal into the standard-definition digital VCR (DV) format or decode the DV format signal into a component video signal. The compression rate of the intraframe compression is about 1/6. The total power dissipation of the two LSI's is 142 mW at 2 V internal supply voltage, which is more than one order of magnitude smaller than the recently reported MPIEG2 (MP@ML) encoder systems. Low power was achieved primarily due to the compression scheme which is optimized for large-scale integration (LSI) implementation. The 0.5-μm 2-V CMOS standard cell library was also effective in reducing the power consumption. Each chip, fabricated in two-layer metal 0.5-μm CMOS technology, contains about 500 k transistors on 71 mm2 and 79 mm2 die, respectively  相似文献   
99.
The creation of effective cancer units is central to the implementation of the report A Policy Framework for Commissioning Cancer Services, produced by the Chief Medical Officers of England and Wales, recently issued by the Department of Health in April 1995. While cancer units are described in this report a range of important questions remain about their nature and how they should be developed. This paper addresses these issues in three ways. A definition of the cancer unit is suggested and its main implications spelt out. The problems of establishing cancer units are covered under three headings. Where should cancer units be? Which cancer sites should the unit cover? What is needed to establish the cancer unit? Finally two checklists are presented, describing the task from the perspectives of the district health authority and hospital(s) concerned. The underlying theme is that real changes in clinical practice and organisation are the goal, and these can only be achieved where there is extensive local dialogue in which the relevant issues are addressed in a structured and rigorous manner. Cosmetic changes in hospital designation will not achieve the consistent quality of cancer service that is the cornerstone of the 'Calman' policy.  相似文献   
100.
To elucidate the role of phosphorylation in regulation of intracellular distribution of myosin II, we have characterized mutant Dictyostelium cells expressing myosin II that could not be regulated by the phosphorylation on the mapped heavy chain sites, the light chain site, or both sites. Immunofluorescence microscopy demonstrated that all three mutant myosin IIs were localized in the furrow region of dividing cells and in the tail region of migrating cells, similar to wild-type cells. Thus, regulation by phosphorylation is not required to direct myosin II toward the furrow region and the tail region in Dictyostelium. However, myosins that were deficient in heavy chain phosphorylation were distributed only in the cortical region of interphase cells, whereas some myosin IIs were present throughout the endoplasm in wild-type cells. Video microscopy showed that the rate of cell migration was significantly lower in cells that were deficient in heavy chain phosphorylation- than in light chain phosphorylation-deficient cells, myosin null cells and wild-type cells. Chemotactic behavior of cells that were deficient in heavy chain phosphorylation was also retarded. These results suggest that loss of regulation by heavy chain phosphorylation results in excessive myosin in the cortex, which leads to retarded motility.  相似文献   
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