全文获取类型
收费全文 | 402篇 |
免费 | 13篇 |
国内免费 | 3篇 |
专业分类
电工技术 | 10篇 |
化学工业 | 58篇 |
金属工艺 | 11篇 |
机械仪表 | 7篇 |
建筑科学 | 7篇 |
能源动力 | 4篇 |
轻工业 | 38篇 |
无线电 | 34篇 |
一般工业技术 | 80篇 |
冶金工业 | 123篇 |
原子能技术 | 4篇 |
自动化技术 | 42篇 |
出版年
2023年 | 3篇 |
2022年 | 3篇 |
2021年 | 9篇 |
2020年 | 6篇 |
2019年 | 3篇 |
2018年 | 5篇 |
2017年 | 9篇 |
2016年 | 5篇 |
2015年 | 2篇 |
2014年 | 2篇 |
2013年 | 20篇 |
2012年 | 23篇 |
2011年 | 17篇 |
2010年 | 15篇 |
2009年 | 14篇 |
2008年 | 10篇 |
2007年 | 7篇 |
2006年 | 5篇 |
2005年 | 14篇 |
2004年 | 9篇 |
2003年 | 12篇 |
2002年 | 8篇 |
2001年 | 6篇 |
2000年 | 6篇 |
1999年 | 17篇 |
1998年 | 40篇 |
1997年 | 30篇 |
1996年 | 23篇 |
1995年 | 11篇 |
1994年 | 7篇 |
1993年 | 9篇 |
1992年 | 2篇 |
1991年 | 8篇 |
1990年 | 5篇 |
1989年 | 13篇 |
1988年 | 14篇 |
1987年 | 3篇 |
1986年 | 4篇 |
1985年 | 2篇 |
1984年 | 3篇 |
1983年 | 2篇 |
1982年 | 1篇 |
1981年 | 2篇 |
1980年 | 1篇 |
1977年 | 1篇 |
1976年 | 4篇 |
1975年 | 1篇 |
1973年 | 1篇 |
1970年 | 1篇 |
排序方式: 共有418条查询结果,搜索用时 15 毫秒
1.
K Kamigiri T Tokunaga T Sugawara K Nagai M Shibazaki B Setiawan RM Rantiatmodjo M Morioka K Suzuki 《Canadian Metallurgical Quarterly》1997,50(7):556-561
Two new types of macrolide antibiotics, YM-32890 A and B, have been isolated from the fermentation broth of cytophaga sp. YL-02905S. In this paper, the taxonomy of the producing strain, fermentation, isolation, structure elucidation, and biological activity of the antibiotics are reported. YM-32890 A inhibits the growth of staphylococci including a macrolide-resistant strain, but shows no antimicrobial activity against other Gram-positive, Gram-negative bacteria and yeast. 相似文献
2.
Y Shioda S Koizumi S Furuya S Akira N Kameyama N Hamano W Takahashi A Tokunaga N Tanaka M Onda 《Canadian Metallurgical Quarterly》1993,23(6):556-561
Respiratory infections are the most common infection in children. They differ remarkably according to age, bacteria and viruses. Therefore a careful history of outbreak, age, former infections, involvement of surroundings, symptoms, etc are essential. The present study included 50 children, aged between 0.3 and 12 yrs, all treated ambulatorily. 21 received brodimoprim (B) and 29 erythromycin (E). Indications were: tonsillitis, bronchitis, otitis media, sinusitis and scarlet fever. Dosages were: B was given 10 mg/kg body weight (b.w.) initially followed by 5 mg/kg b.w., once-a-day. The duration of treatment varied between 4 and 14 days (mean 8.3 days). E was given 30.50 mg/kg b.w. 3 times per day; duration 4 to 14 days (mean 8.6 days). Overall results were: in group B:12 cures, 5 improvements, 3 failures; 1 not assessable. In group E: 20 cures, 8 improvements, 1 failure. Side effects: in group B: vomiting (1), skin reaction (2), discontinuation (2); in group E: skin reaction (1), diarrhea (5), diarrhea+vomiting (1); discontinuation (2). The differences in efficacy and tolerability in the two groups are not statistically significant. The improved compliance with a single versus t.i.d. dosages has to be taken into account. 相似文献
3.
Matsuo N. Matsui H. Tokunaga Y. 《Selected Areas in Communications, IEEE Journal on》1991,9(4):548-554
People faced with an unfamiliar product or service tend to fall back on mental models based on analogical relationships with familiar products or services. Two experiments on the analogical relationships or metaphors that people might use when operating a communications terminal are described. In the first experiment, the role previously acquired operating knowledge has in determining the mental models people use when directory dialing with novel equipment is examined. In a second experiment, it is shown that an explicit appeal to an analogy between conventional mail and electronic mail can help users learn to use an electronic mail system, and make it easier for them to remember how to use the system as long as 90 days after initial exposure. It is concluded that the mental model is constructed only from the user's operating knowledge acquired as a result of past experiences, and the metaphor method is effective when the instructions are metaphorically taught 相似文献
4.
Vera Sheinman Christiane Fellbaum Isaac Julien Peter Schulam Takenobu Tokunaga 《Language Resources and Evaluation》2013,47(3):797-816
We propose a new semantic relation for gradable adjectives in WordNet, which enriches the present, vague, similar relation with information on the degree or intensity with which different adjectives express a shared attribute. Using lexical-semantic patterns, we mine the Web for evidence of the relative strength of adjectives like “large”, “huge” and “gigantic” with respect to their attribute (“size”). The pairwise orderings we derive allow us to construct scales on which the adjectives are located. To represent the intensity relation among gradable adjectives in WordNet, we combine ordered scales with the current WordNet dumbbells based on the relation between a pair of central adjectives and a group of undifferentiated semantically similar adjectives. A new intensity relation links the adjectives in the dumbbells and their concurrent representation on scales. Besides capturing the semantics of gradable adjectives in a way that is both intuitively clear as well as consistent with corpus data, the introduction of an intensity relation would potentially result in several specific benefits for NLP. 相似文献
5.
Human brain disturbance by methylmercury poisoning, focusing on the long-term effect on brain weight
The long-term effects of the initial methylmercury exposure in the Minamata area were examined, with focus on brain weight. Comparisons were made between the brain weights of methylmercury-contaminated persons in the Minamata area (cases) and those of Japanese who suffered sudden or accidental death without brain disease (controls). Since over thirty years have passed since the outbreak of Minamata disease, subjects aged 30 or over at death were included in the analysis. The total number of cases was 417 (273 males, 144 females) and that of controls was 2,934 (2,174 males, 760 females). The data suggest that the brain weights from Minamata cases were reduced by 80 to 200g as compared to the controls. These results may indicate that methylmercury exposure led to a decrease of nerve cells (single cell necrosis), so-called "thinning out", in the brain cortex. 相似文献
6.
This study was conducted to investigate the changes in lipids and their effect on the taste of migaki-nishin during drying. Lipid was extracted from herring fillets following different drying stages to measure the degree of lipid oxidation and changes in lipid composition, and fatty acid profile. Peroxide value, carbonyl value and acid value of the lipids were significantly increased (P < 0.05) during the drying period. Marked increase in free fatty acids, with decreases in triglyceride and phospholipid content were observed in proportion to drying time and this result suggested that hydrolysis was induced by lipases and phospholipases. The decreases in polyunsaturated fatty acids (PUFAs), especially eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), were observed in the total lipids and phospholipid fraction. In addition, significant increase in PUFAs especially DHA was found in the free fatty acid fraction. Sensory evaluation showed that an addition of DHA to mentsuyu significantly (P < 0.05) enhances the intensities of thickness, mouthfulness and continuity. These results suggest that during drying period lipid oxidation was not only occurred but also lipolysis predominantly released DHA, which might have a contribution to kokumi enhancement of migaki-nishin. 相似文献
7.
Kazuya Okamoto Naoto Kume Tatsuya Tokunaga Yoko Tanaka Noriaki Terasawa Takashi Tsukasa Tadamasa Takemura Hiroyuki Yoshihara 《Virtual Reality》2013,17(4):279-292
Understanding what cannot be seen is difficult. Physical behavior can be explained on the basis of physical theories even if the behavior cannot be observed. Explanation of what is physically happening in the real world would become easy, however, if annotations were superimposed on the real objects. Herein, the authors demonstrate how an understanding of a physical event can be facilitated by overlapping a real-world situation with a simulation that predicts a future state. This idea is demonstrated in a game application in which a player stacks blocks into a pile until it collapses. In general, it is easy to estimate whether a block on the edge of a table will fall or not. However, it is more difficult to predict whether a stack of many blocks will collapse, and in what manner the stack will collapse. Even though previous research has demonstrated that the problem of how two-dimensionally stacked blocks collapse can be reduced to solving a sequence of convex quadratic programs, algorithms for convex quadratic programs require massive computational resources. Hence, the authors developed a fast and new algorithm based on a linear program. The proposed algorithm realizes real-time simulation based on physics that superimposes predicted collapse. The block that is predicted to fall is superimposed on the real block with a lit background projection. The system was evaluated in an experiment, and superimposed augmented reality annotation was observed to be efficient. The system was also demonstrated in game contests and received positive feedback and comments. 相似文献
8.
Metal spinning is a plastic forming process in which a disk or tube of metal is rotated at high speed and forced onto a mandrel. It is widely used in industry as an efficient, modern and economical production technique. This research proposes to develop a versatile robotic forming method and expand the application areas of robotic manufacturing processes to the metal spinning area. A lathe-type laboratory setup has been built and an industrial robot manipulator has been used to implement the metal spinning process. Experiments have been conducted with enhanced cascaded trajectory tracking algorithms with an add-on vibration suppressor. The potential of the proposed method has been illustrated with extensive case studies using both constant and variable speed trajectory profiles. Analyses for the growth of wrinkles have been performed through the topographical measurements of the products and the forming forces have been inspected. Results indicate that the efficiency of the process can be significantly improved with suitably selected variable speed trajectory profiles and the process parameters. The developed scheme successfully reduces the excessive oscillations of the manipulator during the metal spinning process and it requires no additional hardware to employ. The investigations demonstrate the feasibility of robotic metal spinning using an industrial serial link manipulator. 相似文献
9.
Koichi Awazu Xiamin Wang Junji Tominaga Hirohiko Aiba Tetsuro Komatsubara 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2009,267(6):941-943
It has been reported that elongated Au nanoparticles oriented parallel to one another can be synthesized in SiO2 by ion irradiation. Our aim was to elucidate the mechanism of this elongation. We prepared Au and Ag nanoparticles with a diameter of 20 nm in an SiO2 matrix. It was found that Au nanoparticles showed greater elongated with a higher flux of ion beam and with thicker SiO2 films. In contrast, Ag nanoparticles split into two or more shorter nanorods aligned end to end in the direction parallel to the ion beam. These experimental results are discussed in the framework of a thermal spike model of Au and Ag nanorods embedded in SiO2. The lattice temperature exceeds the melting temperatures of SiO2, Au and Ag for 100 ns after one 110 MeV Br10+ ion has passed through the middle of an Au or Ag nanorod. 相似文献
10.
Koh Matsumoto Kazutada Ikenaga Jun Yamamoto Kazuki Naito Yoshiki Yano Akinori Ubukata Hiroki Tokunaga Tadanobu Arimura Katsuaki Cho Toshiya Tabuchi Akira Yamaguchi Yasuhiro Harada Yuzaburo Ban Kousuke Uchiyama 《半导体学报》2011,32(1):21-23
Growth rate has a direct impact on the productivity of nitride LED production.Atmospheric pressure growth of GaN with a growth rate as high as 10μm/h and also Al0.1Ga0.9N growth of 1μm/h by using 4 inch by 11 production scale MOVPE are described.XRD of(002) and(102) direction was 200 arcsec and 250 arcsec, respectively.Impact of the growth rate on productivity is discussed. 相似文献