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111.
Whereas many mammals (some primates and mice) experience amodal completion, previous data split for avian species. However, experimental procedures have been quite different among the species, and thus a direct comparison of various avian species in the same experimental situation is needed. We tested whether bantams (Gallus gallus domesticus) would complete partly occluded figures using a visual search task on the touch monitor, which was successfully used in our previous study with pigeons. First, we trained 3 participants to search for a notched red diamond (a target) among complete diamonds (distracters). Next, white squares accompanied each figure with a small gap of a fixed size. In test, the location of the accompanying white squares sometimes changed. In some trials, the white squares exactly covered, or “occluded,” the notched portion of the target. Humans are known to have great difficulty in finding such targets due to “automatic” completion of the notched part. However, bantams met no such difficulty at all. This result and the demonstration by Forkman (1998) of hens' amodal completion of figures placed on a perspective background, suggest that the perspective cue may have an important role in amodal completion in this species. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
112.
针对脂润滑汽车轮毂轴承单元一旦进水可能导致轴承产生异常磨损、锈蚀或提前失效的问题,经过分析与试验,提出通过改变润滑脂添加剂来维持较厚的油膜厚度,并形成坚硬的氧化膜,以避免滚动体与滚道间金属的直接接触、防止滚道面锈蚀及氢元素渗入,达到延长轴承寿命的效果。  相似文献   
113.
This paper outlines the first Asian network-based speech-to-speech translation system developed by the Asian Speech Translation Advanced Research (A-STAR) consortium. Eight research groups comprising the A-STAR members participated in the experiments, covering nine languages, i.e., eight Asian languages (Hindi, Indonesian, Japanese, Korean, Malay, Thai, Vietnamese, and Chinese) and English. Each A-STAR member contributed one or more of the following spoken language technologies: automatic speech recognition, machine translation, and text-to-speech through Web servers. The system was designed to translate common spoken utterances of travel conversations from a given source language into multiple target languages in order to facilitate multiparty travel conversations between people speaking different Asian languages. It covers travel expressions including proper nouns that are names of famous places or attractions in Asian countries. In this paper, we describe the issues of developing spoken language technologies for Asian languages, and discuss the difficulties involved in connecting different heterogeneous spoken language translation systems through Web servers. This paper also presents speech-translation results including subjective evaluation, from the first A-STAR field testing which was carried out in July 2009.  相似文献   
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115.
We investigated an easy way to prepare industrially a conductive paint made with polyaniline (PANI)/dodecylbenzenesulfonic acid (DBSA) dispersion and poly(methyl methacrylate) (PMMA) in organic media. First, water‐dispersible PANI doped with DBSA was chemically synthesized with aniline sulfate using ammonium persulfate in water, and the resulting PANI/DBSA was readily extracted from the reaction medium with a mixture of toluene and methyl ethyl ketone (MEK) (toluene:MEK = 1:1 (v/v)), which is useful for industrial applications. The obtained PANI/DBSA organic dispersion was mixed with PMMA organic solution to give the corresponding PANI/DBSA conductive paint containing PMMA. A film prepared with the resulting PANI/DBSA conductive paint was found to possess relatively good conductivity and low surface resistivity for a conductive paint utilized for an electrostatic discharge even at low PANI/DBSA content in the PANI/DBSA–PMMA composite film (the conductivity and the surface resistivity were 9.48 × 10?4 S cm?1 and 3.14 × 106 Ω cm?2, respectively, when the feed ratio of PANI/DBSA:PMMA was 1:39 (w/w)). Furthermore, it was found that the conductivity of the film composed of PANI/DBSA–PMMA composite can be readily and widely controlled by the PANI/DBSA content of the composite or by the amount of DBSA used during the PANI/DBSA synthesis. The highest conductivity of PANI/DBSA–PMMA composite film (7.84 × 10?1 S cm?1) was obtained when the feed ratio of PANI/DBSA:PMMA was 1:4 (w/w). Copyright © 2007 Society of Chemical Industry  相似文献   
116.
LiCoO2 thin films with nanosize particles were synthesized on Au substrates by nanosheet restacking method and subsequent hydrothermal reaction which needs less cost than the vacuum deposition methods. The grain size of LiCoO2 films estimated by XRD reflection was about 15 nm that was independent of the thickness of precursor cobalt hydroxide film. Comparing the rate performance of the thin films with various thickness, the optimum performance was obtained by the thin film with 5 min deposition time: 62% of the capacity was held at 400 C-rate compared with that at 20 C-rate. The results of AC-impedance analysis of electrode reaction indicate that the high rate capability of the LiCoO2 film is obtained by the small grain size and large surface area of LiCoO2 thin film with nano size particles.  相似文献   
117.
118.
Magnesium hydride is a promising hydrogen source because of its high mass density of hydrogen, 15.2%, when it is hydrolyzed; MgH2 + 2H2O = Mg(OH)2 + 2H2 + 277 kJ. However, a magnesium hydroxide, Mg(OH)2, layer forms rapidly on the surface of the unreacted MgH2 as the pH increases, hindering further reaction. The purpose of this study is to find acids that could effectively accelerate the reaction by using a chemical equilibrium analysis where the relationships of pH to concentration of ionized Mg were calculated. For the best performing acid, the calculated and measured relationships were compared, and the effects of acid concentration on hydrogen release were measured. The analysis revealed that citric acid and ethylenediamine-tetraacetic acid were good buffering agents. The calculated and measured relationships between pH and concentration of ionized Mg were in good accord. Hydrogen release improved considerably in a relatively dilute citric acid solution instead of pure distilled water. The maximum amount of hydrogen generated was 1.7 × 103 cm3 g−1 at STP after 30 min. We estimated the exact concentration of citric acid solution for complete MgH2 hydrolysis by a chemical equilibrium analysis method.  相似文献   
119.
The structure of solid polymer electrode and catalyst ink of fuel cell has been investigated by focusing‐ (FSANS) and contrast‐variation small‐angle neutron scattering (CV‐SANS). The solid polymer electrode, consisting of carbon (C), platinum, and ionomer (polymer, P), exhibited a power‐law function with two asymptotes, i.e., from I(q) ~ q?1 to I(q) ~ q?4 with a crossover around q ≈ 0.005 Å?1. The scattering functions of the catalyst ink, i.e., the polymer electrodes dispersed in water, were successfully decomposed to the corresponding partial structure factors, SCC(q), SPP(q), SCP(q), exclusively representing C‐C, P‐P, and C‐P correlations. SCC(q) was a monotonic decreasing function of q, dominating in the scattering from carbon clusters. On the other hand, SPP(q) exhibited a scattering maximum characteristic of polyelectrolyte solutions. This suggests that ionic clusters in polyelectrolyte solutions are formed in catalyst ink. The cross term, SCP(q), indicated that the carbon scattering is dominant and significant amount of ionomer is adsorbed on the carbon agglomerates. It is concluded that the catalyst ink consists of carbon agglomerates surrounded by ionomers and the presence of ionic‐cluster path plays a key role in the performance of the solid polymer electrodes in polymer electrolyte fuel cells. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 39842.  相似文献   
120.
Experimental studies are reported concerning polarization reversal in the single crystal of telluric acid ammonium phosphate (TAAP). The switching currents have been measured under various temperatures and external electric fields. The experimental results have been used in order to obtain the effective growth dimension of reversed domain and the characteristic time of the polarization reversal on the basis of the Avrami theory. It becomes clear that the effective growth dimension depends on temperature and applied electric field.  相似文献   
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