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排序方式: 共有1306条查询结果,搜索用时 15 毫秒
111.
Chinatsu Okamura Takashi Ueda Kazuhiro Hasezaki 《Journal of Electronic Materials》2010,39(9):2172-2175
Single-phase β-Zn4Sb3 materials were prepared by mechanical grinding (MG). Source materials for the Zn4Sb3 ingots were prepared using three different processes after the direct melting of constituent elements. In process 1, the
ingot was obtained by quenching the melt in water within an evacuated quartz ampoule. In process 2, the ingot was heat-treated
for 100 h at 723 K after process 1. In process 3, the ingot was heat-treated for a total of 200 h in two stages at 723 K and
673 K after process 1. The resultant ingots were mechanically ground and sintered at 623 K by hot pressing. The sintered materials
were characterized by x-ray diffraction, differential thermal analysis (DTA), and thermoelectric property measurements. The
thermal conductivity of the sintered materials was 0.88 W m−1 K−1 at room temperature, being slightly lower than that reported for the materials prepared by a conventional method. Results
indicate that the dimensionless figure of merit of the single-phase β-Zn4Sb3 ranged from 1.06 to 1.31 at 573 K. 相似文献
112.
113.
A fluorous micellar system in water has been created to produce a large interfacial area between these media that retains substrates, effectively facilitating intermolecular Diels–Alder reactions due to repulsion effects from both media. Because LiFOS functioned not only as a surfactant but also as a supporting electrolyte, an electrochemical approach could be introduced to evaluate the rate acceleration effects. The measurement of the particle size distribution of the fluorous micelles clearly supported these evaluations. 相似文献
114.
Kazuhiro Yamaguchi Kohei Miyasaka Naoki Kida Yoshio Nogami Syunichi Tada Hideaki Matsue 《通讯和计算机》2013,(10):1350-1359
In this paper, return link systems for wireless mobile camera using 42 GHz-band in multipath fading environments are proposed. The return link systems for wireless mobile camera require wireless transmission with high reliability as same as the conventional wired camera systems. The proposed return link systems achieve transmission with high reliability by taking into consideration frequency and space diversity techniques. The proposed systems can be classified as 3 three types of return link systems according to diversity techniques: FD (frequency diversity) systems, SD (space diversity) systems and FD+SD system (frequency and space diversity). Computer simulations are carried out in order to confirm the effectiveness of the proposed return link systems. It is confirmed that the proposed three types of return link systems have an advantage about BER performances and effectively exploit frequency and space resources. 相似文献
115.
Sumio Chono Yoshihiko Tauchi Kazuhiro Morimoto 《Drug development and industrial pharmacy》2013,39(1):125-135
ABSTRACTIn order to confirm the efficacy of liposomes as a drug carrier for atherosclerotic therapy, the influence of particle size on the distribution of liposomes to atherosclerotic lesions in mice was investigated. In brief, liposomes of three different particle sizes (500, 200, and 70 nm) were prepared, and the uptake of liposomes by the macrophages and foam cells in vitro and the biodistributions of liposomes administered intravenously to atherogenic mice in vivo were examined. The uptake by the macrophages and foam cells increased with the increase in particle size. Although the elimination rate from the blood circulation and the hepatic and splenic distribution increased with the increase in particle size in atherogenic mice, the aortic distribution was independent of the particle size. The aortic distribution of 200 nm liposomes was the highest in comparison with the other sizes. Surprisingly, the aortic distribution of liposomes in vivo did not correspond with the uptake by macrophages and foam cells in vitro. These results suggest that there is an optimal size for the distribution of liposomes to atherosclerotic lesions. 相似文献
116.
Satoshi Murakami Kazuhiro Satou Taturo Kijima Masataka Watanabe Taeko Izumi 《European Journal of Lipid Science and Technology》2011,113(4):450-458
The enantiopure of (R)‐(?) MαNPA was allowed to react with racemic 18‐(tert‐butyldimethylsilyloxy)‐5‐octadecayne‐7‐ol which was derived from dodecane‐1,12‐diol, yielding diastereomeric esters mixture. These racemic esters were easily separated by HPLC on silica‐gel. The absolute configurations of the first‐eluted diastereomeric esters from the separated esters were determined using 1H NMR anisotropy method. Analysis on 1H NMR spectra and HPLC elution time of the synthesized esters and those of MαNP ester derived from natural methyl‐12‐hydroxystealate showed that the absolute configuration of natural 12‐hydroxystearic acid was R form, and the enantiomeric excess was over 99%. 相似文献
117.
Kazuhiro Fukuyo 《亚洲传热研究》2005,34(7):470-480
The power‐series method, a finite analytic approach to heat transfer and fluid flow problems that is based on power‐series expansion, was applied to a one‐dimensional heat‐conduction problem to evaluate its stability and accuracy. Application to a specific heat‐conduction problem with non‐uniform grid systems showed that it had stability within the ranges 10−5<Δt,ΔxE, and ΔxW,a<105, and 10−5<β<105. Comparison of its solutions with those by the fully implicit and Stefanovic–Stephan methods showed that this method yielded more accurate and robust solutions. © 2005 Wiley Periodicals, Inc. Heat Trans Asian Res, 34(7): 470–480, 2005; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/htj.20085 相似文献
118.
1-Naphthyl isocyanide was polymerized with Ni(II) catalyst in a cholesteric matrix at the liquid crystal (LC) temperature range. The resultant polymers showed optical activity. In this reaction, the structural chirality of cholesteric LC effectively functions to impart one-handed helicity on the corresponding polymers as an optically active atropisomer. 相似文献
119.
Tomohiro Isogai Kazuhiro Hirooka Tetsuro Tojo Hitoshi Takebayashi Morihiro Saito Minoru Inaba Akimasa Tasaka 《Electrochimica acta》2011,56(12):4425
Metal fluoride added carbon anodes treated by pre-electrolysis were investigated for electrolytic production of nitrogen trifluoride (NF3) in molten NH4F·KF·4HF at 100 °C. The conditions for pre-electrolysis were first optimized using a graphite sheet anode as a model anode. The formation of fluorine-graphite intercalation compounds (fluorine-GICs) with semi-covalent C–F bonds, (CxF)n, on the MgF2 and CaF2 added carbon anode surface was accelerated by pre-electrolysis at potentials less than 4.0 V. Critical current densities (CCD) on the MgF2 added carbon anodes pre-electrolyzed under various conditions were determined, and the highest CCD was 290 mA cm−2 obtained for that pre-electrolyzed at 3.5 V for 500 C cm−2. This anode was successfully used in the electrolysis at 100 mA cm−2 for 290 h and the maximum NF3 current efficiency was 55%. From these results, it was concluded that the metal fluoride added carbon anode treated by pre-electrolysis has a high potential for electrolytic production of NF3 at higher current density. 相似文献
120.
Kazuhiro Kimura Kota Sawada Hideaki Kushima 《Transactions of the Indian Institute of Metals》2010,63(2-3):123-129
Creep deformation properties of creep strength enhanced ferritic steels were investigated. Good linear relationships between creep strain vs. time and creep rate vs. time were observed within a transient stage in a double logarithmic plot. It was appropriately expressed by a power law rather than exponential law, logarithmic law and Blackburn’s equation. With decrease in stress, a magnitude of creep strain at the onset of accelerating creep stage decreased from about 2% in the short-term to less than 1% in the long-term. Life fraction of the time to specific strain of 1% creep strain and 1% total strain, to time to rupture tended to increase with decrease in stress. A time to 1% total strain, that is a parameter for design of high temperature components, was observed in the transient creep stage in the short-term regime, however, it shifted to the accelerating creep stage in the long-term regime. Difference in stress dependence of the minimum creep rate was observed in the high- and low-stress regimes with a boundary condition of 50% of 0.2% offset yield stress. Stress dependence of the minimum creep rate in the high stress regime was equivalent to a strain rate dependence of flow stress observed in tensile test, and a magnitude of stress exponent, n, in the high stress regime decreased with increase in temperature from 20 at 550°C to 10 at 700°C. On the other hand, n value in the low stress regime was about 5, and creep deformation in the low stress regime was considered to be controlled by dislocation climb. 相似文献