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41.
Experiments have been carried out to determine the equilibria between FeO x -CaO-SiO2 slag and lead metal in iron crucibles at temperatures ranging from 1473 to 1573 K. It has been found that the highest lead solubilities are observed in the silica-saturated iron silicate slags, while the lowest solubilities are observed in the CaO-saturated calcium ferrite slags. The activity coefficient of PbO varies from 0.15 to 3, depending on the slag composition. Changes in temperature do not have a significant impact on the activity coefficient. The activity of FeO and pct Fe3+/pct Fe2+ ratios have been determined as a function of slag composition. These new experimental data have been incorporated into an optimized thermodynamic slag model using the computer package FACT.  相似文献   
42.
In this paper, the propagation characteristics of a creepage discharge on the surface of a solid insulator with a back electrode in perfluorocarbon liquid under an impulse voltage application are investigated. The propagation process is observed in detail by means of a high‐speed schlieren optical technique, and simultaneously waveforms of a current and a charge are also measured. Consequently, the polarity effect of the streamer propagation and the positive streamer which propagates stepwise can be seen. The latter is concurrent with the sparse current pulse which corresponds to the charge step‐variation. These results are compared with ones obtained in transformer oil. © 2000 Scripta Technica, Electr Eng Jpn, 131(4): 19–28, 2000  相似文献   
43.
A simple and reliable contactless battery charger for electric vehicles is proposed. Its feature is a unitized power factor correcting (PFC) converter and a high‐frequency inverter (HFI) where the low‐side switch of the HFI also works as the boost switch of the PFC in discontinuous conduction mode, which results in a high input power factor and low harmonic distortion without any feedforward control. The exiting current of the inductive connector, compliant with SAEJ1773, works effectively to make the converter operate in zero voltage switching (ZVS) condition. Another feature is that the charger is controlled by a single magnetically coupled variable frequency oscillator developed by the authors. This paper analyzes the circuits, gives a design example, describes the inductive connector and the oscillator, and presents experimental results. A 1.7‐kW output prototype charger achieved a charging efficiency of 87.4% for total one cycle charging, an overall efficiency of 90% at heavy load, and an input power factor of over 98%. © 2000 Scripta Technica, Electr Eng Jpn, 132(2): 73–81, 2000  相似文献   
44.
Effect of ball-mill treatment on physical properties and molecular change of maize starch granule was investigated. Ball-mill treatment was done by rotary type mill, and species of maize starch are normal, waxy and high amylose (amylo). Running time of the treatment is 0–320 h. Starch granules loss smoothness on surface and became rough, even though their changing speed was different among the three species. But, they retained whole figure and size after 320 h treatment in the all cases. Amylase susceptivity and water absorption activity were measured. Structural change of starch components was compared among the three species with X-ray diffraction, DSC and GPC. High Performance An-ion Exchange Chromatography (HPAEC) pattern of debranched sample treated with ball-mill for 320 h showed that formation of very short chain in amylopectin is little. 13C solid-NMR spectra suggest that disruption of molecules of amylopectin and amylose with ball-mill might occur at their glycosidic linkage. However, very slight radical was observed by Electron Spin Resonance spectroscopy (ESR) in the case of 320 h sample.  相似文献   
45.
Rutile-type Ru1−xVxO2 nanoparticles possessing high surface area were prepared by a polymerizable-complex method and its electrochemical supercapacitor behavior was studied. X-ray diffractometry, energy-dispersive X-ray analysis, and N2 adsorption/desorption measurements were used to characterize the structure of the products. The electrochemical supercapacitor behavior of thick and thin films was studied by cyclic voltammetry in various acidic, neutral, and alkaline electrolytes. Ru1−xVxO2 exhibited extremely enhanced supercapacitive properties compared to pure RuO2. The highest surface redox activity was achieved with an acidic electrolyte. Ru1−xVxO2 showed negligible surface redox activity in neutral electrolytes.  相似文献   
46.
Human motion has already deeply affected many aspects of psychological and social research. On the other hand, because of the huge challenges and new dimensions of its increasingly extreme applications, this field remains an inspiring area in which to explore rich possibilities in the fields of artificial intelligence and bio-informatics. In this research, we investigated a novel approach to identify individuals based on their gaits. Furthermore, we investigated a new avenue of the research toward the biometric identification of humans that involves the classification of human gait using the power of genetic programming (GP). Moreover, we also propose an approach that applies collaborative filter using multiple evolved classifiers to address the challenges of non-determinism and insufficient generality of GP.  相似文献   
47.
Raney-type Cu–Pd alloy electrodes were prepared from amorphous Cu–Pd–Zr ternary alloys by treatment with aq. HF, and competitive anodic oxidation reactions of HCHO and HCOO were studied on these electrodes in alkaline media. The initial HCHO oxidation product was HCOO even on Pd or Pd-rich alloy electrodes which should be more active to the HCOO oxidation than to HCHO. The product HCOO was oxidized only after a large decrease of the HCHO concentration in the electrolyte. The oxidation rate of HCOO was considerably lowered by the existence of even a small amount of HCHO, as well as by the introduction of CO. These results suggest that the HCHO electro-oxidation is accompanied by production of a surface contaminant such as adsorbed CO. The optimum nominal Pd atomic fraction in the Cu–Pd alloy electrodes suitable for the steady simultaneous oxidation of HCHO and HCOO in mixed solution was shown to be 0.25 and 0.4 in 1.0 M NaOH (M=moldm–3) and 0.5 M K2CO3, respectively.  相似文献   
48.
本文介绍了最小二乘支持向量机(LS-SVM)回归的基本原理,提出了一种基于LS-SVM回归的时间序列预测器,并将其用于传感器的故障检测和数据恢复。论述了LS-SVM预测器的实现方法和步骤,并且将其应用于压力传感器的故障检测和数据恢复,同线性神经网络预测器、RBF神经网络预测器和BP神经网络预测器的比较结果表明,LS-SVM预测器具有更高的预测精度,更好的外推能力,计算效率最高,因此,LS-SVM预测器是传感器故障检测和短期数据恢复的一种有效方法。  相似文献   
49.
为研究多孔隙岩石的变形特性,提出一个适用于多孔隙岩石的非线形流变模型(本构方程).本模型是由弹簧与阻尼器串连组成,弹簧部分采用作者曾经提出的本构方程;代表黏性部分的阻尼器设定加载前黏度很小,随着荷载的增加而逐渐加大.在低应力水平下的蠕变试验中,由于弹性系数没有明显的下降,因而设定阻尼器的应变与蠕变应变相同.为验证模型的准确性,对泥质砂岩、大谷凝灰岩、田下凝灰岩与河津凝灰岩4类岩石分别进行理论计算与试验测试.对于各类岩石,计算得到的应力-应变曲线与实测曲线基本一致,而且用此流变模型,发现气干与湿润状态下杨氏模量具有明显的差异.研究结果表明,在这2种状态下,杨氏模量的差异是由于非弹性应变(即阻尼器的应变)不同而引起的.在湿润状态下,阻尼器的应变增加越大,杨氏模量则变得越小.即使在较低的应力条件下,阻尼器的应变比以往研究中所认为的应变要大很多.  相似文献   
50.
Spectral control of thermal radiation emitted from rectangular microcavities (0.5×0.5×0.5µm3) was investigated through emission experiments at high temperatures. The microcavities were fabricated on a mirror‐finished Ni metal surface. Through measurement of the normal spectral emittance, the maximum emittance was obtained around a wavelength of 0.87µm, which was very close to that (0.894µm) estimated from the cavity resonance theory. The emittance reached a maximum value of 0.95, and then decreased drastically with increasing wavelength, from the cut‐off wavelength. For a longer wavelength range from 1.7µm, it was equal to the emittance of the mirror‐finished surface. © 2009 Wiley Periodicals, Inc. Heat Trans Asian Res; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/htj.20248  相似文献   
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