全文获取类型
收费全文 | 2105篇 |
免费 | 57篇 |
国内免费 | 8篇 |
专业分类
电工技术 | 100篇 |
综合类 | 2篇 |
化学工业 | 716篇 |
金属工艺 | 86篇 |
机械仪表 | 54篇 |
建筑科学 | 44篇 |
矿业工程 | 3篇 |
能源动力 | 93篇 |
轻工业 | 224篇 |
水利工程 | 8篇 |
石油天然气 | 3篇 |
无线电 | 102篇 |
一般工业技术 | 443篇 |
冶金工业 | 36篇 |
原子能技术 | 65篇 |
自动化技术 | 191篇 |
出版年
2023年 | 9篇 |
2022年 | 33篇 |
2021年 | 44篇 |
2020年 | 25篇 |
2019年 | 39篇 |
2018年 | 41篇 |
2017年 | 33篇 |
2016年 | 49篇 |
2015年 | 43篇 |
2014年 | 62篇 |
2013年 | 118篇 |
2012年 | 102篇 |
2011年 | 130篇 |
2010年 | 117篇 |
2009年 | 124篇 |
2008年 | 125篇 |
2007年 | 118篇 |
2006年 | 94篇 |
2005年 | 74篇 |
2004年 | 85篇 |
2003年 | 70篇 |
2002年 | 56篇 |
2001年 | 41篇 |
2000年 | 42篇 |
1999年 | 37篇 |
1998年 | 47篇 |
1997年 | 35篇 |
1996年 | 31篇 |
1995年 | 24篇 |
1994年 | 27篇 |
1993年 | 20篇 |
1992年 | 25篇 |
1991年 | 26篇 |
1990年 | 16篇 |
1989年 | 15篇 |
1988年 | 8篇 |
1987年 | 22篇 |
1986年 | 17篇 |
1985年 | 16篇 |
1984年 | 14篇 |
1983年 | 9篇 |
1982年 | 19篇 |
1981年 | 14篇 |
1980年 | 15篇 |
1979年 | 16篇 |
1978年 | 7篇 |
1977年 | 9篇 |
1976年 | 9篇 |
1974年 | 4篇 |
1972年 | 3篇 |
排序方式: 共有2170条查询结果,搜索用时 15 毫秒
61.
62.
A Method for Reducing the Dead‐Time Voltage and Impedance Voltage in a Series Voltage Compensator
下载免费PDF全文
![点击此处可从《Electrical Engineering in Japan》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Atsushi Nakata Masahiro Nozaki Akihiro Torii Akiteru Ueda 《Electrical Engineering in Japan》2014,186(3):85-93
Many research groups are developing series voltage compensators. In a series converter, since a transformer is used in series in the power system, the power system current flows into the voltage source inverter through the transformer. The inverter current, which is determined by the transformation ratio, gives rise to an error voltage that consists of a dead‐time voltage and an impedance voltage. The error voltage is generated even when the reference voltage is zero. This paper describes the mechanism by which the error voltage occurs and proposes a method for reducing the error voltage. © 2013 Wiley Periodicals, Inc. Electr Eng Jpn, 186(3): 85–93, 2014; Published online in Wiley Online Library ( wileyonlinelibrary.com ). DOI 10.1002/eej.22333 相似文献
63.
64.
Susumu Fujii Masato Yoshiya Akuto Yumura Yohei Miyauchi Masahiro Tada Hideyuki Yasuda 《Journal of Electronic Materials》2014,43(6):1905-1915
The phonon thermal conductivity of misfit-layered Ca3Co4O9 has been calculated by perturbed molecular dynamics using a classical force field. Detailed numerical analyses reveal that, in spite of its smaller cross-sectional area, the CoO2 layer transports more heat than the thicker rock salt (RS) layer, although its local thermal conduction is more suppressed than in another layered cobaltite, Na x CoO2. The origins of these differences have been elucidated through careful examination of the atomic arrangements in each layer. Since thermal conduction in the RS layer can be reduced without deteriorating electronic properties for which the CoO2 layer is responsible, it is suggested that the RS layer should be modified to further suppress the overall in-plane thermal conductivity. Computational experiments with increasing number of Ca–O planes in the RS layer showed the opposite trend to what can be predicted based on the misfit between two dissimilar layers. Further analyses to reveal the origin of these unexpected results provide yet another strategy to further decrease the thermal conductivity, namely to control the dynamic interference between atoms across the interface between two layers. 相似文献
65.
Mohammed Shahien Motohiro Yamada Masahiro Fukumoto 《Journal of Thermal Spray Technology》2016,25(5):851-873
Reactive plasma spraying (RPS) is a promising technology for the in situ formation of several ceramic coatings. The focus of this paper is to summarize the state of our current knowledge about the RPS process and using the nitriding of Al particles and the fabrication of aluminum nitride coatings, as a case study. The aspects and challenges in this process such as the influence of the plasma power, in-flight time, particle size, nitriding mechanism, splat morphology, in-flight particle diagnostics, N2 plasma gas, and the feeding rate on the RPS process are analyzed and discussed. 相似文献
66.
Toshiaki Ozawa Koji Endo Takashi Masui Masahiro Miyaki Keiko Matsuo Shinji Yamada 《Journal of surfactants and detergents》2016,19(4):785-794
Five anionic surfactants widely used in commercial skin cleansers were studied: sodium polyoxyethylene lauryl ether carboxylate (EC), sodium polyoxyethylene alkyl ether sulfate (ES), sodium dodecyl sulfate, potassium laurate, and N-cocoyl-l-glutamic acid monosodium salt. The amount of surfactant from aqueous solution adsorbed into the stratum corneum (SC), the degree of SC swelling, the change of the secondary structure of SC proteins (denaturation). The surface tension of surfactant–zein mixed solutions, and the solubilization behavior of zein were measured. Results showed that EC had the lowest adsorption into SC, the lowest SC swelling, and lowest denaturation of SC proteins. Low interactions between surfactants and SC proteins were also observed for EC/ES mixture solutions as well as. Mixing EC with ES good foaming performance. The EC/ES mixture, at about 1:1 ratio, is an excellent surfactant system for skin cleanser applications having cleansing characteristics and mildness to the skin. 相似文献
67.
Chiho Miyamaru Mao Koide Nana Kato Shogo Matsubara Masahiro Higuchi 《International journal of molecular sciences》2022,23(2)
We fabricated CaCO3-coated vesicles as drug carriers that release their cargo under a weakly acidic condition. We designed and synthesized a peptide lipid containing the Val-His-Val-Glu-Val-Ser sequence as the hydrophilic part, and with two palmitoyl groups at the N-terminal as the anchor groups of the lipid bilayer membrane. Vesicles embedded with the peptide lipids were prepared. The CaCO3 coating of the vesicle surface was performed by the mineralization induced by the embedded peptide lipid. The peptide lipid produced the mineral source, CO32−, for CaCO3 mineralization through the hydrolysis of urea. We investigated the structure of the obtained CaCO3-coated vesicles using transmission electron microscopy (TEM). The vesicles retained the spherical shapes, even in vacuo. Furthermore, the vesicles had inner spaces that acted as the drug cargo, as observed by the TEM tomographic analysis. The thickness of the CaCO3 shell was estimated as ca. 20 nm. CaCO3-coated vesicles containing hydrophobic or hydrophilic drugs were prepared, and the drug release properties were examined under various pH conditions. The mineralized CaCO3 shell of the vesicle surface was dissolved under a weakly acidic condition, pH 6.0, such as in the neighborhood of cancer tissues. The degradation of the CaCO3 shell induced an effective release of the drugs. Such behavior suggests potential of the CaCO3-coated vesicles as carriers for cancer therapies. 相似文献
68.
Cheol Ho Pyeon Masao Yamanaka Akito Oizumi Masahiro Fukushima Go Chiba Kenichi Watanabe 《Journal of Nuclear Science and Technology》2019,56(8):684-689
This study demonstrates, for the first time, the principle of nuclear transmutation of minor actinide (MA) by the accelerator-driven system (ADS) through the injection of high-energy neutrons into the subcritical core at the Kyoto University Critical Assembly. The main objective of the experiments is to confirm fission reactions of neptunium-237 (237Np) and americium-241 (241Am), and capture reactions of 237Np. Subcritical irradiation of 237Np and 241Am foils is conducted in a hard spectrum core with the use of the back-to-back fission chamber that obtains simultaneously two signals from specially installed test (237Np or 241Am) and reference (uranium-235) foils. The first nuclear transmutation of 237Np and 241Am by ADS soundly implemented by combining the subcritical core and the 100 MeV proton accelerator, and the use of a lead-bismuth target, is conclusively demonstrated through the experimental results of fission and capture reaction events. 相似文献
69.
Bacterial alkaline phosphatase (BAP) was site-specifically and covalently immobilized on magnetic particles (MPs) using the enzymatic reaction of microbial transglutaminase (MTG). Immobilization efficiency was affected by the chemical surface treatment of MPs and immobilized BAP exhibited more than 90% of the initial activity after 10 rounds of recycling. 相似文献
70.
Masayuki Akiyama Masashi Tatsuzaki Tomomi Michishita Toshikazu Ichiki Masahiro Sumi Michio Ikeda Tetsuya Araki Yasuyuki Sagara 《Food and Bioprocess Technology》2012,5(5):1924-1938
To design a consumer-oriented package that complements the taste and aroma of ready-to-drink chilled-cup coffee beverages by using the food kansei model, the effects of the diameter and the color of drinking straws as well as the cognition terms of coffee on consumer sensory characteristics and preferences were investigated. Variance and factor analyses of the sensory scores for chilled-cup coffee with milk and sugar using straws of different diameters, as rated by consumer panelists, extracted two perceived factors (F1, contribution ratio 36.5%, and F2, 28.6%). A two-dimensional plot of the average F1 and F2 scores of 123 panelists showed that the perceived characteristics of the same taste and aroma varied according to the straw diameter. An image investigation of different straw colors and another sensory evaluation using “black,” “brown,” and “green” straws were also performed. A principal component analysis of the image data revealed that the sensory characteristics of coffee with milk and sugar were imaged from the straw color. The second evaluation suggested that the images of straw colors affected the sensory characteristics. In addition, cluster and multiple-comparison analyses of Internet research data from consumers regarding the cognition terms for coffee exhibited three clusters representing the cognitive characteristics of terms by consumers and by developers and the differences of attractiveness degree on the cognition terms due to the consumers’ personal attributes. These studies provide useful information for the development of packages of chilled-cup coffee beverages. 相似文献