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排序方式: 共有115条查询结果,搜索用时 15 毫秒
41.
In this paper, we describe a self-aligned process to produce short-channel vertical power DMOSFETs in 4H-SiC. By reducing the channel length to /spl les/0.5 /spl mu/m, the specific on-resistance of the MOSFET channel is proportionally reduced, significantly enhancing performance. 相似文献
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Md. Abdul Matin Ji-Hoon Jang Eunjik Lee Young-Uk Kwon 《Journal of Applied Electrochemistry》2012,42(10):827-832
Pt-doped Pd nanoparticle catalysts (Pd n Pt, n is 12, 15 and 19) supported on carbon were synthesized by an ultrasound assisted polyol method. The catalysts were characterized by X-ray diffraction, transmission electron microscopy, and energy dispersive X-ray spectroscopy. The electrochemical activity of the electrocatalysts was investigated in terms of formic acid oxidation reaction (FAOR) at low concentration of formic acid in 0.1 M perchloric acid at room temperature. Formic acid oxidation on the Pd n Pt/C commences at lower potential than a commercial Pt/C. Pd19Pt/C catalyst showed the highest catalytic activity in FAOR compared to that of other catalysts. The obtained electrochemical results from voltammograms indicate that Pt-doped Pd catalysts can be a promising candidate for the anode material in direct formic acid fuel cells. The synthesis procedure is not only a very facile route but also a mass producible method for preparing carbon supported alloy nanoparticles. 相似文献
44.
Houwen Tang M. A. Matin Heli Wang Shet Sudhakar Le Chen Mowafak M. Al-Jassim Yanfa Yan 《Journal of Electronic Materials》2012,41(11):3062-3067
A major drawback for CuO as an efficient photocathode in photoelectrochemical (PEC) water splitting is its instability in aqueous solution. In this paper, we report that Ti alloying can enhance the stability of CuO in PEC water splitting but at the cost of reduced crystallinity and optical absorption, and therefore reduced photocurrent. We further report that a balance between the stability and photocurrent can be realized by a bilayer configuration—a thin Ti-alloyed CuO layer on a pure CuO thin film. Our results indicate that the thickness of the top Ti-alloyed CuO layer should be optimized to realize the best stability and photocurrent. 相似文献
45.
Rubayyat Mahbub Takian Fakhrul Md. Fakhrul Islam Mehedi Hasan Arman Hussain M.A. Matin M.A. Hakim 《金属学报(英文版)》2015,28(8):958
The main focus of the research was to correlate the microstructure with dielectric and magnetic properties of Bi1-xBaxFeO3 samples. Bi1-xBaxFeO3 samples(x = 0.1, 0.2 and 0.3) were synthesized by the conventional solid-state reaction method using nano-powders of Bi2O3, Fe2O3, and BaCO3. Thereafter, field emission scanning electron microscope and X-ray diffraction(XRD) techniques were used to examine the structure and phase of the samples. Phase analysis by XRD indicated that the single-phase perovskite structure was formed with possible increment in lattice parameter with increasing Ba doping. Complex permeability(u'iand u'i) measured using impedance analyzer confirmed the increase in magnetic property with increasing Ba doping. Finally, dielectric constant(k) was analyzed as a function of temperature at different frequencies. Dielectric constant as high as 2900 was attained in this research for Bi0.8Ba0.2FeO3 sample due to reduction in leakage current at this composition. 相似文献
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Mohamed Abusnina Helio Moutinho Mowafak Al-Jassim Clay DeHart Mohammed Matin 《Journal of Electronic Materials》2014,43(9):3145-3154
In this work, Cu2ZnSnS4 (CZTS) thin films were prepared by the sulfurization of metal precursors deposited sequentially via radio frequency magnetron sputtering on Mo-coated soda-lime glass. The stack order of the precursors was Mo/Zn/Sn/Cu. Sputtered precursors were annealed in sulfur atmosphere with nine different conditions to study the impact of sulfurization time and substrate temperature on the structural, morphological, and optical properties of the final CZTS films. X-ray fluorescence was used to determine the elemental composition ratio of the metal precursors. Final CZTS films were characterized by x-ray diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive spectroscopy (EDS). XRD and EDS were combined to investigate the films’ structure and to identify the presence of secondary phases. XRD analysis indicated an improvement in film crystallinity with an increase of the substrate temperature and annealing times. Also indicated was the minimization and/or elimination of secondary phases when the films experienced longer annealing time. EDS revealed slight Sn loss in films sulfurized at 550°C; however, an increase of the sulfurization temperature to 600°C did not confirm these results. SEM study showed that films treated with higher temperatures exhibited dense morphology, indicating the completion of the sulfurization process. The estimated absorption coefficient was on the order of 104 cm?1 for all CZTS films, and the values obtained for the optical bandgap energy of the films were between 1.33 eV and 1.52 eV. 相似文献
49.
Matin Ahooghalandari Mehdi Khiadani Mina Esmi Jahromi 《Water Resources Management》2016,30(11):3815-3828
Quantifying reference evapotranspiration (ET0) is essential in water resources management. Although, many methods have been developed with different level of accuracy, in this study, two new equations were developed and optimized for estimating ET0 using Honey-Bee Mating Optimization (HBMO) algorithm. The first eq. estimates ET0 from extraterrestrial radiation (Ra), relative humidity (RH) and mean daily temperature (Tmean), while the second uses the same parameters except that mean daily temperatures is replaced with maximum daily air temperature (Tmax). Both equations were developed using climatic data from eight weather stations in Western Australia and subsequently verified using data from ten sites across Australia. The estimated ET0 values from both equations versus the FAO56-Penman-Monteith have a coefficient of determination, R2, of larger than 0.96. Moreover, the performance of six commonly used methods of estimating ET0 including Hargreaves-Samani, Thornthwaith, Hamon, Mc Guinness-Bordne, Irmak and Jensen-Haise were assessed and the Hargreaves-Samani method performed better than others. An attempt was made to calibrate the Hargreaves-Samani equation; however, its overall performance did not improved and the two newly proposed equations are suggested to be used in Australia. 相似文献
50.
The effects of ionizing radiation doses between 1 and 20 krad on all stages of Rhyzopertha dominica were studied. Adult emergence from treated eggs and larvae was prevented by 4 and 8 krad respectively. Doses up to 20 krad to pupae only slightly reduced the emergence of adults. However there was considerable (up to 30 per cent) mortality of the adults within 8 hours of eclosion. The 20 krad dose caused very high mortality of adults from irradiated pupae and of irradiated adults within 3–5 weeks. Complete sterility, as evidenced by the lack of an F1 generation, was induced in pupae by a dose of 14 krad and in adults by 11·5 krad. 相似文献