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51.
Journal of Materials Science: Materials in Electronics - In this work, a triple hexagonal split ring resonator incorporated metamaterial sensor is proposed for the improved detection of fuel...  相似文献   
52.
In this paper, a new design for the flow channels is presented, and a parametric study of the proton exchange membrane (PEM) fuel cell is conducted in order to investigate the effect of the new flow channels, as well as different operating parameters, on the efficiency and energy output of the cell. Design parameters are selected based on studies presented in the literature to build a physical and practical model. With the new design of the flow channels, it is noticed that the cell efficiency increases from 33.8% to 47.7% if the temperature of the cell is increased. The power output of the cell increases from 2.6 to 282.5 W when the cell temperature and the current density are increased. Moreover, decrease in the efficiency of the cell ranges from 45.5% to 28.4% with the increase in the current density and membrane thickness. Based on the analytical model, design parameters were selected to manufacture a fuel cell that has a power output of 175 W and an efficiency of 35% running at 353 K and 3 bar, with an effective membrane area of 450 cm2. Experiments are conducted to investigate the effect of newly designed flow channels on pressure distribution. It is found that when hydrogen is supplied from both inlets, pressure across the channels become symmetric and, therefore increasing the power output. This study reveals that, with the proper choice of design parameters, a PEM fuel cell is an attractive economical, efficient, and environmental solution when compared with conventional systems of power generation such as gas turbines. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
53.
A continued analysis of the meaning of "opposite speech," i.e., the use of the reverse apparently intended, in schizophrenics, accompanied by a clinical illustration. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
54.
The damage distributions induced by ultra low energy ion implantation (5 keV Si+) in both strained-Si/Si0.8Ge0.2 and normal Si are measured using high-resolution RBS/channeling with a depth resolution better than 1 nm. Ion implantation was performed at room temperature over the fluence range from 2 × 1013 to 1 × 1015 ions/cm2. Our HRBS results show that the radiation damage induced in the strained Si is slightly larger than that in the normal Si at fluences from 1 × 1014 to 4 × 1014 ions/cm2 while the amorphous width is almost the same in both strained and normal Si.  相似文献   
55.
The present work is accounted on the designing of a new and efficient asymmetric organic chromophore, named 4-(3,5-bis [trifluoromethyl] phenyl)-7-(5′-hexyl-[2,2′-bithiophen]-5-yl)-benzo[c [1, 2, 5]selenadiazole, (RT-BSe-F), based on benzoselenadiazole central acceptor building blocks. The acceptor unit of 3,5-bis (trifluoromethyl) benzene and donor unit of alkyl bithiophene attached with benzoselenadiazole central unit showed large impacts on the optical and electrochemical properties. The reasonable optical band gap of ~2.02 eV and HOMO of −5.33 eV were obtained by RT-BSe-F chromophore due to a strong electron accepting nature of fluorine based compound. With 3,5-bis(trifluoromethyl) benzene unit, the absorption of RT-BSe-F chromophore was considerably increased to higher wavelength which might enhance the crystallinity of thin film with high hole mobility. RT-BSe-F chromophore was effectively applied to fabricate the solution-processed bulk-heterojunction organic solar cells (BHJ-OSCs) and attained a high power conversion efficiency (PCE) of ~3.75% accompanying high JSC of ~12.56 mA cm−2, FF of ~0.42 and VOC of ~0.71 V. The obtained high PCE might be associated to a high surface energy of TiO2 layer as buffer and the use of high mobility organic RT-BSe-F chromophore.  相似文献   
56.
The aim of this paper is to present an overview of published research in selective laser sintering/melting (SLS/M), by using bibliometric indicators. Bibliometrics is the quantitative statistical analysis of written publications, such as articles or books. It is useful for displaying and classifying information according to selected variables, such as authors, journals, citations, countries, and institutions. This type of review provides a clear picture of research in a targeted area, such as the most cited research, author with most publications, journal with most published papers, and universities and countries producing the largest amount of research in the target area. The Web of Science database was used to collect data on the topic of interest. The results reveal that the Rapid Prototyping journal is the most productive journal in this field, where the Huazhong University Science Technology is the most effective institution. Also China is the most productive country, whereas USA is the most influential country.  相似文献   
57.
Porous cobalt oxide (Co3O4) nanocubes (NCs) were synthesized by a simple and cost-effective hydrothermal technique for the potential application of electrochemical supercapacitors. The hydrothermally synthesized materials exhibited the small cube like morphology with the average size of ~ 50 to 60 nm. The surface analysis revealed a good surface area, and high pore volume of the synthesized porous Co3O4 NCs. The capacitive properties of porous Co3O4 NCs electrode were investigated by cyclic voltammetry (CV) in 6 M KOH electrolyte and a high specific capacitance of ~ 430.6 F/g at a scan rate of ~ 10 mV s?1 was observed. The capacity retention of up to ~ 85% after 1000 cycles was shown by the fabricated porous Co3O4 NCs electrode. The porous Co3O4 NCs showed excellent structural stability through cycling with promising capacity retention which suggested a good quality of porous Co3O4 NCs as electrochemical supercapacitor electrode.  相似文献   
58.
Deblurring computed tomography (CT) images has been an active research topic in recent years because of the wide variety of challenges it offers. Hence, a novel filter is proposed in this article unveiling a simple, efficient, and fast deblurring process that involves few parameters, low calculations and does not utilize the undesirable iterative property or introduce the common deblurring problems. The newly proposed filter is validated on both real and synthetic blurred CT images to provide a sufficient understanding about its performance. Moreover, proper comparisons are made with high‐profile deblurring methods, in which the results are evaluated using three reliable quality metrics of feature similarity index (FSIM), structural similarity (SSIM), and visual information fidelity in pixel domain (VIFP). The intensive experiments and performance evaluations exhibited the efficiency of the proposed filter, in that it outperformed all the comparative methods. © 2015 Wiley Periodicals, Inc. Int J Imaging Syst Technol, 25, 265–275, 2015  相似文献   
59.
An inorganic/organic hetrostructure diode was constructed by the electrophoretic deposition of the p-type polyaniline (PANI) on an n-type titanium oxide (TiO2) nanoparticulate thin film. The bonding and internalization of PANI to TiO2 nanoparticulate thin film were confirmed by the morphological, structural and optical studies of electrophoretically deposited PANI/TIO2 nanoparticulate thin film. The increased size of TiO2 nanoparticles indicated the well penetration of PANI molecules into the pores of mesoporous TiO2 nanoparticulate thin film. The XPS studies of PANI/TiO2 heterostructure exhibited the surface bonding and interaction between PANI molecules and TiO2 nanoparticles. The current-voltage (I-V) characterization of PANI/TiO2 heterostructure was carried out in the forward and the reverse bias at the applied voltage ranges from -1 V to +1 V with a scan rate of 2 mV/s. The constructed Pt/PANI/TiO2 heterostructure device established diodic behavior with non-linear nature of I-V curves.  相似文献   
60.
The novel organic-inorganic nanocomposites were synthesized via in-situ polymerization of polyaniline (PANI) with mesoporous silica (MCM-41) for methylene blue (MB) dye degradation under visible light. The synthesized PANI/MCM-41 nanocomposites were characterized through Fourier transform infrared (FTIR), X-ray diffraction (XRD), Raman spectroscopy, field emission scanning electron microscopy (FESEM), and UV-visible studies. The structural and optical properties confirmed the interaction between PANI and MCM-41. The photocatalytic experiments showed that the MB dye was efficiently degraded by approximately 70% under light irradiation over the surface of the PANI/MCM-41 nanocomposites. The degradation might occur due to the efficient charge separation of the e(-)-h+ pairs at the interface of PANI and MCM-41 in the excited state under light irradiation.  相似文献   
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