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81.
An architecture for a nonvolatile RAM (NVRAM) suitable for high-density applications is described. In the cell, a dynamic RAM cell is merged into an EEPROM cell. A capacitor is constructed between the control gate and the drain diffusion layer of the FLOTOX-type EEPROM memory cell. The equivalent circuit in the dynamic RAM mode consists of two transistors and a capacitor, which eliminates a dummy cell. A dynamic RAM sense amplifier is used in both modes, and it works as a data latch when data are transferred between the dynamic RAM and the EEPROM. The process of the NVRAM is compatible with ordinary EEPROMs  相似文献   
82.
2,3-Bisphosphoglycerate mutase (BPGM) [EC 5.4.2.4] is a multifunctional enzyme that catalyzes both the synthesis and the degradation of 2,3-diphosphoglycerate (2,3-DPG) and contains three types of activities in that it functions as a 2,3-DPG synthetase, a phosphoglycerate mutase and a 2,3-DPG phosphatase. In humans, BPGM occurs only in erythrocytes and plays a pivotal role in the dissociation of oxygen from hemoglobin via 2,3-DPG. The present study shows that the specific activity of BPGM in erythrocytes of diabetic patients is decreased, compared to normal controls as judged by 2,3-DPG synthetase activity and immunoreactive contents. To understand the mechanism by which the enzyme is inactivated, the enzyme was purified from pooled erythrocytes from diabetic patients and subjected to a boronate affinity column. The flow through fraction was active while the bound fraction was completely inactive. The bound fraction was reactive to an anti-hexitollysine antibody, indicating that the enzyme had undergone glycation and inactivation. The primary glycated site of the enzyme was found to be Lys158 as judged by amino acid sequencing and the reactivity with an anti-hexitollysine IgG, after reverse-phase HPLC of the lysyl-endopeptidase-digested peptides. Extensive glycation of recombinant BPGM in vitro indicated that the glycation sites were Lys2, Lys4, Lys17, Lys42, Lys158, and Lys196. From these results, the loss of enzymatic activity appears to be due to the glycation of Lys158 which may be located in the vicinity of the substrate binding site.  相似文献   
83.
The test module plant which is a quarter fragment of the conceptually designed, desalting plant with capacity of 100,000 m3/d has been operated as an activity of the national project in Japan. The type of the desalting plant is a high flow rate long tube multistage flash evaporator which is designed on the basis of the result achieved by the systematic research of the project. Where, condensing heat transfer tubes of length 33.6 m were successfully installed, and the reinforced concrete shell in the heat rejecting section is practiced without any trouble as a corrosion free vessel. The data acquisition system for the test module deals with 600 data which are classified into the total process, the concrete shell, the test sections and the pretreatment process. In the test section, temperature distribution of the brine flow is intended to measure at an accuracy of the order of 0.01°C. The paper describes these results on the basis of the recent information, and gives a scope for expecting effect on the progress of desalination technology.  相似文献   
84.
85.
The thermodynamic properties (solubility, vapour pressure, density, viscosity, heat capacity and heat of mixing) of the H2O + CH3OH + LiBr + ZnCl2 (9:1 H2O:CH3OH and 1:1 LiBr:ZnCl2 by mass) system using H2O + CH3OH as the working media and LiBr + ZnCl2 as the absorbents were measured. The solubility data were obtained in the temperature range from 270.35 to 389.55 K. The measurements of vapour pressure, density, viscosity and heat capacity were carried out at various temperatures and absorbent concentrations. The differential heat of dilution and differential heat of solution at 298.15 K were measured for solutionw with absorbent concentrations from 0 to 75.2 wt%. The integral heat of mixing data at 298.15 K were obtained from both sets of experimental data. The integral heats of mixing for this quaternary system showed exothermic behaviour. The vapour pressure data were correlated with an Antoine-type equation. An empirical formula for the heat capacity was obtained from experimental data. The experimental data for the basic thermodynamic properties of this quaternary system were compared with those of the basic H2O + LiBr system.  相似文献   
86.
This paper describes the basic concepts, design and implementation decisions, standpoints and significance of the database machine Delta in the scope of Japan’s Fifth Generation Computer Project. Delta is planned to be operational in 1985 for researchers’ use as a backend database machine for logic programming software development. Delta is basically a relational database machine system. It combines hardware facilities for efficient relational database operations, which are typically represented by relational algebra, and software which deals with hardware control and actual database management requirements. Notable features include attribute-based internal schema in accordance with the characteristics found in the relation access from logic programming environment. This is also useful for the hardware relational algebra manipulation algorithm based on merge-sorting of attributes by hardware and a large capacity Semiconductor Disk for fast access to databases. Various implementation decisions of database management requirements are made in this novel system configuration, which will be meaningful to give an example for constructing a hardware and software combination of a relational database machine. Delta is in the stage between detailed design and implementation.  相似文献   
87.
Fatigue behaviour was investigated for low-strength silica fibres on which macroscopic flaws were forcibly introduced by abrading. Crack growth in silica glass was also examined on the CT specimen. Stable crack growth parameters, obtained from the static and dynamic fatigue tests for abraded fibres, were determined to be about 40 which is equal to that obtained from the CT specimen, indicating that the crack growth process in abraded fibres is quite the same as in the CT specimen. This leads to the conclusion that, for the optical fibre, the allowable stress condition wherein no breaks occur is given on the basis of some basic fracture mechanics parameters obtained from the CT specimen.  相似文献   
88.
Stable crack-propagation behaviour in silica glass as a raw material for optical fibres is studied under static tensile stress in various environments such as distilled water, NaCl aqueous solution, air and dry nitrogen gas, and the influence of these environments is discussed. The crack-growth rate in distilled water is obtained qualitatively as a function of the stress intensity factor and temperature, and the activation energy of the cracking process is determined as 97.6 kcal mol–1. The growth rate seems to be unaffected by Na+ and Cl ions in an NaCl acqueous solution, but is influenced significantly by the humidity in the atmosphere. In a dry atmosphere, the growth rate in Region II cannot be expressed as a single function of the stress intensity factor. A plot of the log of time to failure against the initial stress intensity factor reveals a linear relationship in the environments tested. The critical fracture stress of an optical fibre is evaluated taking account of the crack size on the basis of fracture mechanics concept.  相似文献   
89.
The following paper describes a mitral valve replacement (SJM 27 mm), the patch closure (EPTFE) of an ostium primum atrial septal defect and tricuspid annuloplasty (De Vega's method) in a 64-year-old female patient with an incomplete endocardial cushion defect and mitral stenosis. Surgery revealed thickened, mitral valve leaflets and the presence of a cleft, findings similar to those observed in case of rheumatic degeneration. Investigation of patient hemodynamics confirmed a diagnosis of Lutembacher syndrome and a lower with left ventricle volume. After surgery, the volume of left ventricle increased and the patients clinical course was uneventful.  相似文献   
90.
We investigated the basic characteristics of the pulsatility of motor current with an in vitro mock circuit that consists of a sac-type pulsatile pump (simulating the natural left ventricle), three reservoirs, and our mixed flow pump (MFP). There are three alternatives at the inlet of the MFP: 1) the left atrium (LA), 2) the left ventricle (LV), and 3) both (LALV). The motor current waveform was monitored. The pump speed of the MFP was changed from 0 to 7,000 rpm. We calculated the index of motor current amplitude (ICA), which was obtained from the amplitude of the motor current waveform divided by the simultaneous mean value. The ICA plotted against the pump speed had a peak point (t-point) that highly corresponded with the turning point from partial to total left heart assistance. The ICA also had a second specific point (s-point) that corresponded with the beginning of severe sucking. In LV and LALV aortic bypass, t- and s-points could clearly be detected. In LA aortic bypass, however, early and severe sucking occurred, and t- and s-points were not manifest. These data suggest that the assist status of continuous flow artificial heart can be estimated by detecting the t- and s-points.  相似文献   
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