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81.
Due to the industrial applications of nasno materials, the growth of Copper oxide (CuO) nanowires (NWs) at the same and opposite directions of the electric and gravitational fields was investigated to study the effects of fields on the NWs properties. The experiments were designed to grow NWs using thermal oxidation method at 450 °C for 50 h. NWs growth was evaluated to study two distinct cases; first, substrates exposed to the gravitational field and second those treated with electric field (EF) in-lined with gravitation field (GF). It was observed that the electric field developed a diameter homogeneity while compressing the NWs and decreasing the diameters. Furthermore, the GF influenced only the length of the NWs, while the EF had an impact on both length and diameter of the NWs. The direction of fields played an important role in NWs morphology and intensity of XRD pattern and optical properties. It was also observed that field direction greatly influenced the NWs length and diameter.  相似文献   
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The effect of different extraction methods i.e. extraction with alkali (AEDF), enzyme (EEDF) and enzyme plus shear emulsifying hydrolysis (SEDF) on structure, physiochemical as well as the functional characteristics of dietary fiber (DF) from defatted walnut flour were studied. AEDF process showed significantly higher (P < 0.05) amount of water retention capacity (WRC; 5.39 g/g), water swelling capacity (WSC; 3.16 g/mL), and particle size; while, shown lower value of oil adsorption capacity (OAC; 29 g/g) amongst all. Compared to AEDF, no major differences were observed in network except the matrix in EEDF and SEDF was more porous and honey comb like. DF extracted through AEDF, EEDF and SEDF showed good viscosity and emulsifying activity however, less stability indices. The results from this study suggest that AEDF and EEDF and SEDF had specific effects on the structure-functional properties of DF from defatted walnut flour, which has great potential in food applications.  相似文献   
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The most widely used methods for the assessment of beta-cell response and peripheral tissue sensitivity to insulin include the oral glucose tolerance test (OGTT), the frequently sampled intravenous glucose tolerance test, and the hyperinsulinemiceuglycemic clamp technique. During an OGTT, glucose levels increase after a variable lag period, then reach a peak and fall variably among individuals. The response even varies in the same subject upon repeat testing. A more reproducible glucose curve is achieved with an intravenous glucose tolerance test in which the plasma glucose levels rise rapidly to a very high level and fall exponentially. In neither of the two methods is a steady-state glucose level achieved. In the hyperinsulinemic-euglycemic clamp technique, a steady-state glucose level can be maintained at any level of hyperinsulinemia. However, an assessment of beta-cell sensitivity is not obtained. The less used hyperglycemic clamp technique can assess beta-cell sensitivity as well as peripheral tissue sensitivity. Moreover, a measure of glucose effectiveness or non-insulin-mediated glucose uptake can also be determined. With this technique the beta-cells of all subjects are stimulated with the same arterial glucose concentration, thus enabling assessment of beta-cell response to identical plasma glucose levels. Comparison of responses to stable hyperglycemic stimuli can be made in glucose-tolerant and -intolerant states with the addition of various substances, either alone or in combination. The use of the hyperglycemic clamp and several of its variant forms is reviewed as an alternative method for assessment of glucose homeostasis.  相似文献   
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We have conducted a retrospective study of deaths on a paediatric medical intensive care unit over a two-year period and reviewed similar series from outside the UK. There were 89 deaths out of 651 admission (13.7% mortality). In almost two-thirds of the cases death occurred with a decision to limit medical treatment or withdraw mechanical ventilation, implying that additional or further therapy was considered futile. We highlight this as a crucially important issue in the practice of intensive care. More comprehensive studies are needed to help clinicians derive consensus on what constitutes a futile intervention, and therefore when such an intervention should be withheld. This will help families and society better understand the limitations of intensive care.  相似文献   
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The high-energy current of runaway electrons during a major disruption in tokamak reactors can cause serious damage to the first wall of the reactor and reduce its lifetime. Therefore, it is important to find methods for decreasing the generation of runaway electrons and their energy. The safety factor plays an important role in determining the stability criteria for a wide range of MHD modes. Since runaway electrons suffer only rarely from collisions and are hardly sensitive to electrostatic turbulence, their transport is governed by the magnetic lines structure. On the other hand, since the safety factor is related to the magnetic lines structure, changes in safety factor may have important effects on the diffusion of runaway electrons. In this paper, the generation of runaway electrons and their transport is investigated theoretically. Moreover, by changing the discharge voltage of ohmic and toroidal capacitors, different values of the edge safety factor is generated. In fact, in this experiment, the researchers try to increase the diffusion of runaway electrons by using safety factor changes in the IR-T1 tokamak.  相似文献   
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The research reported in this paper is a contribution in understanding the epoxy injection retrofitting technique to strengthen the existing RC cracked members. This technique consists of injecting epoxy resin adhesive in a cracked beam to increase the stiffness and the strength. A total of six full scale RC beams were constructed with the same material using the same mix and water-cement ratio. The beams were tested until the width of cracks reached a limiting value of 1 mm. The beams were then repaired with the epoxy injection technique. After 3 days of water curing, the beams were tested again and loaded till the failure occurred. A considerable enhancement in the load carrying capacity was observed in the beams after the retrofitting. A reduction in deflection was also observed due to the injection of epoxy. These results clearly demonstrate the effectiveness of the proposed technique in repairing the RC members for strengthening the existing structures.  相似文献   
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Long‐term deterioration in the performance of PEFCs is attributed largely to reduction in active area of the platinum catalyst at cathode, usually caused by carbon‐support corrosion. It is found that the use of graphitic carbon as cathode‐catalyst support enhances its long‐term stability in relation to non‐graphitic carbon. This is because graphitic‐carbon‐supported‐Pt (Pt/GrC) cathodes exhibit higher resistance to carbon corrosion in‐relation to non‐graphitic‐carbon‐supported‐Pt (Pt/Non‐GrC) cathodes in PEFCs during accelerated stress test (AST) as evidenced by chronoamperometry and carbon dioxide studies. The corresponding change in electrochemical surface area (ESA), cell performance and charge‐transfer resistance are monitored through cyclic voltammetry (CV), cell polarisation and impedance measurements, respectively. The degradation in performance of PEFC with Pt/GrC cathode is found to be around 10% after 70 h of AST as against 77% for Pt/Non‐GrC cathode. It is noteworthy that Pt/GrC cathodes can withstand even up to 100 h of AST with nominal effect on their performance. X‐ray diffraction (XRD), Raman spectroscopy, transmission electron microscopy and cross‐sectional field‐emission scanning electron microscopy (FE‐SEM) studies before and after AST suggest lesser deformation in catalyst layer and catalyst particles for Pt/GrC cathodes in relation to Pt/Non‐GrC cathodes, reflecting that graphitic carbon‐support resists carbon corrosion and helps mitigating aggregation of Pt‐particles.  相似文献   
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