全文获取类型
收费全文 | 1324篇 |
免费 | 24篇 |
专业分类
电工技术 | 52篇 |
化学工业 | 320篇 |
金属工艺 | 70篇 |
机械仪表 | 33篇 |
建筑科学 | 18篇 |
能源动力 | 23篇 |
轻工业 | 71篇 |
水利工程 | 6篇 |
石油天然气 | 1篇 |
无线电 | 130篇 |
一般工业技术 | 224篇 |
冶金工业 | 243篇 |
原子能技术 | 30篇 |
自动化技术 | 127篇 |
出版年
2023年 | 3篇 |
2022年 | 17篇 |
2021年 | 17篇 |
2020年 | 8篇 |
2019年 | 6篇 |
2018年 | 18篇 |
2017年 | 11篇 |
2016年 | 19篇 |
2015年 | 16篇 |
2014年 | 31篇 |
2013年 | 51篇 |
2012年 | 43篇 |
2011年 | 67篇 |
2010年 | 43篇 |
2009年 | 60篇 |
2008年 | 78篇 |
2007年 | 60篇 |
2006年 | 42篇 |
2005年 | 57篇 |
2004年 | 42篇 |
2003年 | 35篇 |
2002年 | 42篇 |
2001年 | 40篇 |
2000年 | 26篇 |
1999年 | 33篇 |
1998年 | 109篇 |
1997年 | 67篇 |
1996年 | 53篇 |
1995年 | 26篇 |
1994年 | 33篇 |
1993年 | 25篇 |
1992年 | 13篇 |
1991年 | 14篇 |
1990年 | 16篇 |
1989年 | 12篇 |
1988年 | 14篇 |
1987年 | 13篇 |
1986年 | 8篇 |
1985年 | 13篇 |
1984年 | 9篇 |
1983年 | 10篇 |
1982年 | 3篇 |
1980年 | 3篇 |
1979年 | 3篇 |
1978年 | 6篇 |
1977年 | 8篇 |
1976年 | 13篇 |
1975年 | 3篇 |
1972年 | 3篇 |
1968年 | 2篇 |
排序方式: 共有1348条查询结果,搜索用时 15 毫秒
1.
Ken Kanazawa Shoji Yoshida Hidemi Shigekawa Shinji Kuroda 《Science and Technology of Advanced Materials》2015,16(1)
The reconstructed surface structure of the II–VI semiconductor ZnTe (110), which is a promising material in the research field of semiconductor spintronics, was studied by scanning tunneling microscopy/spectroscopy (STM/STS). First, the surface states formed by reconstruction by the charge transfer of dangling bond electrons from cationic Zn to anionic Te atoms, which are similar to those of IV and III–V semiconductors, were confirmed in real space. Secondly, oscillation in tunneling current between binary states, which is considered to reflect a conformational change in the topmost Zn–Te structure between the reconstructed and bulk-like ideal structures, was directly observed by STM. Third, using the technique of charge injection, a surface atomic structure was successfully fabricated, suggesting the possibility of atomic-scale manipulation of this widely applicable surface of ZnTe. 相似文献
2.
Sachiyuki Hasegawa Kazuyuki Shimizu Takeshi Kobayashi Masakazu Matsubara 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1985,35(1):33-42
Repeated batch operation using two fermentors (RBTF) to penicillin fermentation was demonstrated by computer simulation to improve productivity. Three operation modes were compared: chemostat, repeated batch operation using a single fermentor (RBSF) and RBTF; in each case account was made of the lag period before growth. The simulated fermentor performances were assessed on the basis of the penicillin productivity and concentration; the simulation was based on published batch fermentation data. It was shown that RBTF was superior to RBSF and chemostat. The advantage of RBTF increased as the lag period became greater. 相似文献
3.
Y. L. Hao R. Yang M. Niinomi D. Kuroda Y. L. Zhou K. Fukunaga A. Suzuki 《Metallurgical and Materials Transactions A》2003,34(4):1007-1012
Alloys for implant devices require improved strength but a reduced Young’s modulus, in order to become mechanically more compatible
with adjacent bone tissues. In this study, a new metastable β-type titanium alloy, Ti-29Nb-13Ta-4.6Zr (wt pct), was subjected to aging treatment to produce different microstructures,
and the resulting mechanical properties, including the Young’s modulus, were measured. The Young’s modulus of this alloy is
found to be sensitive to microstructures generated by various heat treatments. For microstructures varying from (α + β) to (α + β + ω) and (β + ω), the Young’s modulus increases with an accompanying increase in tensile strength and hardness, but decreases in ductility.
The (β + ω) microstructure has a low strength, high modulus, and poor ductility and cannot be used for biomedical applications. For
an (α + β) microstructure, the volume fraction of the phases is shown to be the main factor that determines the mechanical properties. 相似文献
4.
Iida M. Kuroda N. Otsuka H. Hirose M. Yamasaki Y. Ohta K. Shimakawa K. Nakabayashi T. Yamauchi H. Sano T. Gyohten T. Maruta M. Yamazaki A. Morishita F. Dosaka K. Takeuchi M. Arimoto K. 《Solid-State Circuits, IEEE Journal of》2005,40(11):2296-2304
A 16 Mb embedded DRAM macro in a fully CMOS logic compatible 90 nm process with a low noise core architecture and a high-accuracy post-fabrication tuning scheme has been developed. Based on the proposed techniques, 61% improvement of the sensing accuracy is realized. Even with the smallest 5 fF/cell capacitance, a 322 MHz random-cycle access while 32 ms data retention time which contributes to save the data retention power down to 60 /spl mu/W are achieved. 相似文献
5.
S Matsuoka K Mori O Nakano Y Yuasa Y Taguchi Y Hayabuchi Y Kuroda 《Canadian Metallurgical Quarterly》1997,156(9):704-708
Twenty-two children with chronic hepatitis serologically positive for hepatitis C virus (HCV) were treated with interferon-alpha (IFN-alpha). Liver biopsy showed chronic active hepatitis in 13 and chronic persistent hepatitis in 9 patients. A sustained clearance of HCV was observed in 8/22 children 12 months after the administration of IFN-alpha for 26 weeks, associated with normalization of HCV core antibody. Of these eight patients six had HCV genotype III and two HCV genotype II or IV. Hepatitis relapsed in seven other patients after completion of IFN-alpha with an increase in HCV core antibody titre, five with HCV genotype II, and two with HCV genotype III or IV. A second course of IFN-alpha suppressed the reactivation of HCV in all seven patients. Three of seven responders who relapsed after the first course remained negative for HCV RNA 12 months after their second course of IFN-alpha. However, the remaining four patients with HCV genotype II again relapsed after completing their second course of IFN-alpha. Seven children with the HCV genotype II resistant to IFN, including 8 weeks of IFN-beta administration, and showed no significant reduction in HCV core antibody titre. CONCLUSION: The genotype of HCV (III) and a reduction in the core antibody titre appear to be useful parameters for predicting the response to IFN-alpha therapy. 相似文献
6.
T Kuroda T Shimamoto T Mizushima T Tsuchiya 《Canadian Metallurgical Quarterly》1997,179(23):7600-7602
The activity of the NhaA Na+/H+ antiporter of Vibrio parahaemolyticus is inhibited by amiloride. We found an amino acid sequence in the NhaA that was identical to a putative amiloride binding domain of the Na+/H+ exchanger in mammalian cells. We constructed mutant NhaAs that had amino acid substitutions in the putative amiloride binding domain by site-directed mutagenesis. These include V62L (Val62 replaced by Leu), F63Y, F64Y, and L65F. Most mutant NhaAs showed decreased sensitivity for amiloride. Among these, the F64Y mutant NhaA showed the least amiloride sensitivity, with a Ki value 7 to 10 times greater than that in the wild type. Thus, the sequence between residues V62 and L65 in NhaA, especially F64, is very important for the inhibitory effect of amiloride on the antiporter. 相似文献
7.
Anju Sawada Takehiro Kubo Yosikazu Abe Kazuyuki Matsumoto 《Journal of Low Temperature Physics》1995,101(3-4):707-712
The isochoric pressure of bcc Solid3He in the vicinity of the triple point has been measured by changing the temperature stepwisely and waiting for thermal equilibrium. We observed anomalous pressure kinks of the temperature dependence in the paramagnetic region near the triple point. This anomaly appeared at 0.37 to 0.40 tesla, and disappeared below 0.36 tesla. Moreover, critical phenomena at the transition point from the paramagnetic phase (PP) to the high field phase was observed and the phase line curves toward the PP side. 相似文献
8.
T Takeshita T Arita H Asao N Tanaka M Higuchi H Kuroda K Kaneko H Munakata Y Endo T Fujita K Sugamura 《Canadian Metallurgical Quarterly》1996,225(3):1035-1039
We molecularly cloned a cDNA coding for a novel phosphotyrosine molecule with a 70 kDa molecular mass, named STAM (signal transducing adaptor molecule), which is tyrosine-phosphorylated rapidly after stimulation with various cytokines such as IL-2, IL-3, IL-4, IL-7, GM-CSF, EGF and PDGF. STAM contains an SH3 (Src-homology 3) domain and the ITAM (immunoreceptor tyrosine-based activation motif), suggesting that STAM acts as an adaptor molecule involved in signal transducing pathways from the cytokine receptors. 相似文献
9.
Neogi A. Everitt H. Morkoc H. Kuroda T. Tackeuchi A. 《Nanotechnology, IEEE Transactions on》2003,2(1):10-14
Self-assembled GaN quantum dots (QDs), grown on AlN by molecular beam epitaxy, were investigated by time-resolved photoluminescence spectroscopy. We investigate the emission mechanism in GaN QDs by comparing the carrier recombination dynamics in single and multiple period QDs. At 100 K, the PL decay time in single period QD structures is considerably shorter than in stacked QDs. Compared to single period QDs, the room temperature PL efficiency is considerably enhanced in 20 period QDs due to the reduction in nonradiative recombination processes. 相似文献
10.
Cooperative behavior of various agents in dynamic environment 总被引:5,自引:0,他引:5
Akihide Hiura Toshiya Kuroda Nobuhiro Inuzuka Ken-ichi Itoh Masashi Yamada Hirohisa Seki Hidenori Itoh 《Computers & Industrial Engineering》1997,33(3-4):601-604
The multi-agent model is a model in which agents with limited ability cooperate each other to accomplish a goal. In this paper, we introduce a multi-agent model in which agents are created to imitate real ants. There are two different type of agents, each type of which has a particular task. We designed agents to communicate each other by using pheromone considering noise. On this model, we observed cooperative behavior of agents and evaluated conditions to make an order of behavior in the model. 相似文献