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81.
Yoichi Kumada Daisuke Kuroki Hidefumi Yasui Takuhito Ohse Michimasa Kishimoto 《Journal of Bioscience and Bioengineering》2010,109(6):583-587
In this study, we characterized polystyrene-binding peptides (PS-tags) that possess a specific binding affinity for hydrophilic polystyrene (phi-PS) plates. Both the FITC-labeled PS19-1 (RAFIASRRIKRP) and PS19-6 (RIIIRRIRR) peptides showed strong binding affinity for commercially available hydrophilic, but not hydrophobic, PS plates in the presence of the non-ionic surfactant Tween 20. The dissociation constants (Kd) of the PS19-1 and PS19-6 peptides for the hydrophilic PS-A plate were 169 and 86 nM, respectively, and the Kd of both peptides increased with the concentration of NaCl or urea. Based on adsorption yield and residual activity of glutathione S-transferase (GST) after fusion with the PS19-6 peptide or its variants, it was found that the basic amino acid in the PS-tags, i.e., Arg was essential for the strong binding affinity of PS-tags in both the peptide and peptide-fused protein forms The aliphatic amino acids in PS19-6 and PS19-6L, such as Ile or Leu, were also effective. Thus, a series of PS-tags that possess this unusual feature, especially the peptides PS19-6 (RIIIRRIRR) and PS19-6L (RLLLRRLRR), are potential candidate affinity peptide tags for site-specific immobilization of proteins onto hydrophilic PS plates, which show potential as solid supports for protein-based biochips. 相似文献
82.
0引言SUGAWARA(菅原)轴承测试系统,是由日本SUGAWARA(菅原)研究所开发的一款高品质测试系统,系统具有集成度高、精准、安全、操作简单、维护轻松等特点,且具有测试范围广、外观高档、分析功能强大等优点。该系统广泛应用于研发、质量认证、检测、轴承测试领域,其代表客户有美蓓 相似文献
83.
Hyun-Chul Ko Doo-Cheol Park Yoichi Kawakami Shizuo Fujita Shigeo Fujita Chai-ok Kim 《Journal of Materials Science Letters》1997,16(13):1187-1190
Abstracts are not published in this journal
This revised version was published online in November 2006 with corrections to the Cover Date. 相似文献
84.
This paper describes a business intelligence application of neural networks in analyzing consumer heterogeneity in the context of eating-out behavior in Taiwan. We apply a neural network rule extraction algorithm which automatically groups the consumers into identifiable segments according to their socio-demographic information. Within each of these segments, the consumers are distinguished between those who eat-out frequently from those who do not based on their psychological traits and eat-out considerations. The data set for this study has been collected through a survey of 800 Taiwanese consumers. Demographic information such as gender, age and income were recorded. In addition, information about their psychological traits and eating-out considerations that might influence the frequency of eating-out were obtained. The results of our data analysis show that the neural network rule extraction algorithm is able to find distinct consumer segments and predict the consumers within each segment with good accuracy. 相似文献
85.
86.
Improved Filtration Performance of Continuous Alumina-fiber-reinforced Mullite Composites for Hot-Gas Cleaning 总被引:1,自引:0,他引:1
Satoshi Kitaoka Naoki Kawashima Yoshinobu Komatsubara Akira Yamaguchi Hisao Suzuki 《Journal of the American Ceramic Society》2005,88(1):45-50
The effect of filtration layer morphology on filtration performance at 673 K was investigated for continuous alumina-fiber-reinforced mullite composite filters that capture fly ash on their outer surfaces. Two types of filtration layers were prepared on the outer surfaces: a mono-layer consisting of mullite agglomerated particulates and a bi-layer, with mullite whiskers formed by a vapor-phase reaction and strongly adhered to the particulates exposed on the outer surfaces. For filters with mono-filtration layers, the filtration efficiency was improved slightly by increasing the filtration layer thickness. However, the maximum differential pressure increased during the filtration tests. Adhesion of whiskers to the outer surface decreased the maximum differential pressure to about one-third less than that with the mono-filtration layer. This low differential pressure remained constant throughout the duration of the test, with corresponding increases in filtration efficiency. 相似文献
87.
Yamori A. Yanagisawa M. Sato K. Kawashima N. Furukawa T. Teii S. 《IEEE transactions on magnetics》1991,27(1):126-129
A railgun for the study of the interaction of meteorites with planetary surfaces and the interaction of space debris was developed. The authors have attained a velocity constantly higher than 5 km/s, with a maximum of 6 km/s. The importance of plasma confinement behind the projectile to prevent a leakage is shown to realize a high velocity. An effective acceleration using an aluminum rail is also shown 相似文献
88.
Yoichi Morales Alexander Carballo Eijiro Takeuchi Atsushi Aburadani Takashi Tsubouchi 《野外机器人技术杂志》2009,26(8):609-635
This paper describes an implementation of a mobile robot system for autonomous navigation in outdoor concurred walkways. The task was to navigate through nonmodified pedestrian paths with people and bicycles passing by. The robot has multiple redundant sensors, which include wheel encoders, an inertial measurement unit, a differential global positioning system, and four laser scanner sensors. All the computation was done on a single laptop computer. A previously constructed map containing waypoints and landmarks for position correction is given to the robot. The robot system's perception, road extraction, and motion planning are detailed. The system was used and tested in a 1‐km autonomous robot navigation challenge held in the City of Tsukuba, Japan, named “Tsukuba Challenge 2007.” The proposed approach proved to be robust for outdoor navigation in cluttered and crowded walkways, first on campus paths and then running the challenge course multiple times between trials and the challenge final. The paper reports experimental results and overall performance of the system. Finally the lessons learned are discussed. The main contribution of this work is the report of a system integration approach for autonomous outdoor navigation and its evaluation. © 2009 Wiley Periodicals, Inc. 相似文献
89.
Zhanpeng Lu Tetsuo Shoji Yoichi Takeda Yuzuru Ito Akira Kai Seiya Yamazaki 《Corrosion Science》2008,50(2):561-575
The stress corrosion cracking (SCC) growth kinetics for a cold worked 316L stainless steel was continuously monitored in high purity water at different temperatures and dissolved oxygen (DO) levels under a K (or Kmax) of 30 MPa m0.5. The total SCC test time was more than 8000 h to make sure the steady state crack growth rate under each test condition could be reached. Crack growth rate (CGR) increases with increasing temperature in the range 110-288 °C. A typical intergranular-cracking mode is identified. Depending on the previous test condition, especially the temperature, three kinds of crack growth kinetics, i.e., increasing with testing time then becoming steady, being constant during the whole period, or decreasing with test time then becoming steady, are identified and discussed. Time-dependent and testing history-dependent crack growth modes were confirmed in two series of tests in 2 ppm DO and 7.5 ppm DO pure water. The apparent activation energies are calculated and compared with other data in different environments under different applied loading levels for understanding the cracking mechanism. 相似文献
90.
S Mikami S Kawashima K Kanazawa K Hirata H Hotta Y Hayashi H Itoh M Yokoyama 《Canadian Metallurgical Quarterly》1997,81(4):504-511
Recent reports demonstrated the expression of inducible-type NO synthase in the heart of viral myocarditis. Since NO has multiple biological actions, a substantial amount of NO produced in the diseased heart may act either as a cytotoxic or as a cytoprotective molecule in the process of myocarditis. In the present study, we examined the effect of inhibition of NO synthesis on the mortality and the extent of myocardial injury in a murine model of coxsackievirus B3-induced myocarditis. We fed the infected mice drinking water containing a relatively low concentration (0.37 mmol/L) of N omega-nitro-L-arginine methyl ester (L-NAME) for 14 days after virus inoculation. This dose of L-NAME did not change virus titers in the heart. However, L-NAME-fed mice showed a significant reduction in mortality compared with those fed normal drinking water (nontreated mice). On the contrary, mice given a higher concentration of L-NAME (3.7 mmol/L) exhibited increased mortality. In addition, mice fed a low concentration of L-NAME showed reductions in the severity of heart failure and in the area of myocardial necrosis. Although systemic blood pressure was reduced in nontreated mice, in mice fed a low concentration of L-NAME, it was maintained at a level similar to that in uninfected control mice, L-NAME-treated mice also exhibited a reduction in the degree of inflammatory cell infiltration associated with decreased production of tissue prostaglandin E2 levels in the heart compared with nontreated mice. Therefore, NO is likely to be involved in the pathogenic mechanisms of myocardial injury and resultant cardiac dysfunction in a murine model of coxsackievirus B3-induced viral myocarditis. 相似文献