全文获取类型
收费全文 | 299篇 |
免费 | 4篇 |
专业分类
电工技术 | 9篇 |
化学工业 | 126篇 |
金属工艺 | 19篇 |
机械仪表 | 3篇 |
建筑科学 | 11篇 |
能源动力 | 3篇 |
轻工业 | 29篇 |
无线电 | 26篇 |
一般工业技术 | 33篇 |
冶金工业 | 23篇 |
原子能技术 | 6篇 |
自动化技术 | 15篇 |
出版年
2023年 | 1篇 |
2021年 | 13篇 |
2020年 | 3篇 |
2019年 | 5篇 |
2018年 | 9篇 |
2017年 | 5篇 |
2016年 | 4篇 |
2015年 | 3篇 |
2014年 | 7篇 |
2013年 | 12篇 |
2012年 | 16篇 |
2011年 | 19篇 |
2010年 | 9篇 |
2009年 | 11篇 |
2008年 | 5篇 |
2007年 | 10篇 |
2006年 | 4篇 |
2005年 | 8篇 |
2004年 | 7篇 |
2003年 | 13篇 |
2002年 | 6篇 |
2001年 | 3篇 |
2000年 | 9篇 |
1999年 | 8篇 |
1998年 | 15篇 |
1997年 | 10篇 |
1996年 | 13篇 |
1995年 | 8篇 |
1994年 | 2篇 |
1993年 | 4篇 |
1992年 | 3篇 |
1991年 | 8篇 |
1990年 | 2篇 |
1989年 | 3篇 |
1988年 | 3篇 |
1987年 | 1篇 |
1986年 | 3篇 |
1985年 | 1篇 |
1984年 | 6篇 |
1983年 | 6篇 |
1982年 | 4篇 |
1981年 | 3篇 |
1980年 | 5篇 |
1979年 | 6篇 |
1978年 | 2篇 |
1977年 | 4篇 |
1976年 | 1篇 |
排序方式: 共有303条查询结果,搜索用时 15 毫秒
1.
Sakama Chiaki Inoue Katsumi Sato Taisuke 《Annals of Mathematics and Artificial Intelligence》2021,89(12):1133-1153
Annals of Mathematics and Artificial Intelligence - This paper introduces a novel approach to computing logic programming semantics. First, a propositional Herbrand base is represented in a vector... 相似文献
2.
Photocatalysts have attracted great research interest owing to their excellent properties and potential for simultaneously addressing challenges related to energy needs and environmental pollution. Photocatalytic particles need to be in contact with their respective media to exhibit efficient photocatalytic performances. However, it is difficult to separate nanometer-sized photocatalytic materials from reaction media later, which may lead to secondary pollution and a poor recycling performance. Hydrogel photocatalysts with a three-dimensional (3D) network structures are promising support materials for photocatalysts based on features such as high specific surface areas and adsorption capacities and good environmental compatibility. In this review, hydrogel photocatalysts are classified into two different categories depending on their elemental composition and recent progresses in the methods for preparing hydrogel photocatalysts are summarized. Moreover, current applications of hydrogel photocatalysts in energy conversion and environmental remediation are reviewed. Furthermore, a comprehensive outlook and highlight future challenges in the development of hydrogel photocatalysts are presented. 相似文献
3.
Yukinori Matsukura Chiaki T. Oguchi Nobuaki Kuchitsu 《Bulletin of Engineering Geology and the Environment》2004,63(2):167-176
To clarify the mechanism of salt fretting of a brick building, monthly observations were made over one year at a two-storey brick kiln in central Japan. Products of weathering that had fallen were collected and weighed; salts were identified using XRD and the moisture content of the brick was measured at its surface using a portable infrared optical moisture meter. Gypsum (CaSO4·2H2O) was found at the bottom of the first floor wall in the warm and humid season. Thenardite (Na2SO4) is dominant on the first floor wall; it is abundant in the cold and dry season but sparse in the warm and humid season. Magnesium sulphate is dominant on the second floor wall; epsomite (MgSO4·7H2O) was observed in the dry-to-wet season and hexahydrite (MgSO4·6H2O) in the wet-to-dry season. Seasonal changes in salt abundance result from the temperature dependence of the solubilities and equilibrium relative humidities (ERH) of each salt. The amount of brick decay material due to salt weathering is much greater from the second floor wall than from the first floor wall and is greater from spring to the end of summer. These seasonal and spatial variations of the rate of brick decay can be explained by a combination of factors: (1) the types of salt, (2) efflorescence or sub-florescence and (3) salt deliquescence. 相似文献
4.
An ultrasonic treatment system, using a TiO2 photocatalyst, was used to disinfect Legionella pneumophila. A kinetic study of the process indicates that TiO2 significantly improves the disinfection process. The concentrations of viable cells were reduced to 6% of the initial concentrations in the presence of 0.2 g/ml TiO2 after a 30 min of treatment period, while only an 18% reduction was observed in the absence of TiO2. The potency of the disinfection could be enhanced, to some extent, by increasing the amount of TiO2 used. Cell concentrations were decreased by an order of 3 within 30 min of treatment in the presence of 1.0 g/ml TiO2. The disinfection power in the presence of TiO2 versus Al2O3 was also compared and the findings showed that TiO2 induced a higher cell killing. No significant effect of initial cell concentration on the disinfection was found in the range of 102-107 CFU/ml after a 30 min of treatment period. The mechanism of cell killing was investigated by examining the effects of OH radical scavengers such as ascorbic acid, histidine and glutathione. The disinfection power was reduced in samples that contained these radical scavengers, thus indicating the importance of OH radicals. 相似文献
5.
Rina Sakai Yuji Morikawa Chiaki Kondo Hiroyuki Oka Hirofumi Miyajima Kihei Kubo Takeki Uehara 《International journal of molecular sciences》2014,15(10):17256-17269
In vitro mammalian cytogenetic tests detect chromosomal aberrations and are used for testing the genotoxicity of compounds. This study aimed to identify a supportive genomic biomarker could minimize the risk of misjudgments and aid appropriate decision making in genotoxicity testing. Human lymphoblastoid TK6 cells were treated with each of six DNA damage-inducing genotoxins (clastogens) or two genotoxins that do not cause DNA damage. Cells were exposed to each compound for 4 h, and gene expression was comprehensively examined using Affymetrix U133A microarrays. Toxicogenomic analysis revealed characteristic alterations in the expression of genes included in cyclin-dependent kinase inhibitor 1A (CDKN1A/p21)-centered network. The majority of genes included in this network were upregulated on treatment with DNA damage-inducing clastogens. The network, however, also included kinesin family member 20A (KIF20A) downregulated by treatment with all the DNA damage-inducing clastogens. Downregulation of KIF20A expression was successfully confirmed using additional DNA damage-inducing clastogens. Our analysis also demonstrated that nucleic acid constituents falsely downregulated the expression of KIF20A, possibly via p16 activation, independently of the CDKN1A signaling pathway. Our results indicate the potential of KIF20A as a supportive biomarker for clastogenicity judgment and possible mechanisms involved in KIF20A downregulation in DNA damage and non-DNA damage signaling networks. 相似文献
6.
Akira Minami Yuuki Kurebayashi Tadanobu Takahashi Tadamune Otsubo Kiyoshi Ikeda Takashi Suzuki 《International journal of molecular sciences》2021,22(6)
Sialidase cleaves sialic acid residues from glycans such as glycoproteins and glycolipids. In the brain, desorption of the sialic acid by sialidase is essential for synaptic plasticity, learning and memory and synaptic transmission. BTP3-Neu5Ac has been developed for sensitive imaging of sialidase enzyme activity in mammalian tissues. Sialidase activity in the rat hippocampus detected with BTP3-Neu5Ac increases rapidly by neuronal depolarization. It is presumed that an increased sialidase activity in conjunction with neural excitation is involved in the formation of the neural circuit for memory. Since sialidase inhibits the exocytosis of the excitatory neurotransmitter glutamate, the increased sialidase activity by neural excitation might play a role in the negative feedback mechanism against the glutamate release. Mammalian tissues other than the brain have also been stained with BTP3-Neu5Ac. On the basis of information on the sialidase activity imaging in the pancreas, it was found that sialidase inhibitor can be used as an anti-diabetic drug that can avoid hypoglycemia, a serious side effect of insulin secretagogues. In this review, we discuss the role of sialidase in the brain as well as in the pancreas and skin, as revealed by using a sialidase activity imaging probe. We also present the detection of influenza virus with BTP3-Neu5Ac and modification of BTP3-Neu5Ac. 相似文献
7.
This article proposes a new method to measure the creep strength of adhesively bonded joints using a hydro-pneumatic testing machine and a specimen holder, on which multi-specimens can be mounted in one testing machine. Creep tests were conducted on stainless steel butt joints bonded with epoxy adhesives. A hydro-pneumatic loading system was introduced to avoid successive failures of multi-specimens as well as to achieve a stable and constant loading through the experiments. Even after a failure occurs in one of the joints and thus generates an impact, the loading system is capable of absorbing the shock so that the other remaining joints do not fail simultaneously. It was experimentally verified that choke valves, which were introduced in the hydraulic circuit of the system, worked as a damper when failure occurred. Additionally, it was established that automatic reloading to the remaining specimens after the failure was short enough compared with the creep rupture time. As this new method relates to the efficiency of creep testing, the utility of the proposed approach with the multi-specimen setup has been verified. 相似文献
8.
<正>大船渡市属于日本西北部的岩手县,位于颇具特色的三陆海岸线上。大船渡市民文化会馆暨市立图书馆作为一个文化建筑综合体,包含了一个容纳1100个座位的大剧场、图书室、多功能剧场、画室、茶室以及工作室。工程在进展过程中组织了超过50次的各种区域性研 相似文献
9.
Construction of an error map of rotary axes on a five-axis machining center by static R-test 总被引:1,自引:0,他引:1
Soichi Ibaraki Chiaki OyamaHisashi Otsubo 《International Journal of Machine Tools and Manufacture》2011,51(3):190-200
This paper proposes an efficient and automated scheme to calibrate error motions of rotary axes on a five-axis machining center by using the R-test. During a five-axis measurement cycle, the R-test probing system measures the three-dimensional displacement of a sphere attached to the spindle in relative to the machine table. Location errors, defined in ISO 230-7, of rotary axes are the most fundamental error factors in the five-axis kinematics. A larger class of error motions can be modeled as geometric errors that vary depending on the angular position of a rotary axis. The objective of this paper is to present an algorithm to identify not only location errors, but also such position-dependent geometric errors, or “error map,” of rotary axes. Its experimental demonstration is presented. 相似文献
10.
Mihashi Mutsuko; Otsubo Yasunao; Yinjuan Xin; Nagatomi Kaori; Hoshiko Michiko; Ishitake Tatsuya 《Canadian Metallurgical Quarterly》2009,28(1):91
Objective: To investigate strategies for broad mass isolation during outbreaks of infectious diseases. Design: A survey using a self-administered questionnaire was conducted on 300 printing company workers in Beijing, China, which was under mass isolation following the 2003 SARS outbreak, in the 7-8 months after the isolation was lifted. Main Outcome Measures: Individuals with psychological disorders were classified on the basis of scores on the 30-item General Health Questionnaire during the recovery period. Psychological disorders were observed in 49 of 187 respondents (26.2%; 95% CI = 20.2, 32.7). Results: The predicting factor with the highest correlation was income reduction, with an odds ratio of 25.0. Other items obtained were gender, range of activities, eating restrictions, restrictions in going out, disinfection of clothing, and infection control, with odds ratios of 3.2, 5.5, 3.9, 3.2, 0.2, and 0.1, respectively, and the contribution ratio was 87.7%. Conclusion: Securing income is suggested to be important in future strategies. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献