全文获取类型
收费全文 | 425篇 |
免费 | 12篇 |
国内免费 | 2篇 |
专业分类
电工技术 | 24篇 |
化学工业 | 171篇 |
金属工艺 | 16篇 |
机械仪表 | 7篇 |
建筑科学 | 6篇 |
能源动力 | 7篇 |
轻工业 | 39篇 |
水利工程 | 2篇 |
石油天然气 | 6篇 |
无线电 | 20篇 |
一般工业技术 | 62篇 |
冶金工业 | 25篇 |
原子能技术 | 8篇 |
自动化技术 | 46篇 |
出版年
2023年 | 2篇 |
2022年 | 12篇 |
2021年 | 13篇 |
2020年 | 6篇 |
2019年 | 3篇 |
2018年 | 10篇 |
2017年 | 5篇 |
2016年 | 13篇 |
2015年 | 6篇 |
2014年 | 16篇 |
2013年 | 24篇 |
2012年 | 17篇 |
2011年 | 30篇 |
2010年 | 18篇 |
2009年 | 27篇 |
2008年 | 14篇 |
2007年 | 28篇 |
2006年 | 9篇 |
2005年 | 15篇 |
2004年 | 10篇 |
2003年 | 12篇 |
2002年 | 12篇 |
2001年 | 10篇 |
2000年 | 10篇 |
1999年 | 18篇 |
1998年 | 13篇 |
1997年 | 10篇 |
1996年 | 11篇 |
1995年 | 4篇 |
1994年 | 9篇 |
1993年 | 8篇 |
1992年 | 4篇 |
1991年 | 5篇 |
1990年 | 3篇 |
1989年 | 4篇 |
1988年 | 2篇 |
1987年 | 3篇 |
1986年 | 2篇 |
1985年 | 1篇 |
1984年 | 4篇 |
1983年 | 3篇 |
1982年 | 2篇 |
1981年 | 5篇 |
1979年 | 2篇 |
1978年 | 1篇 |
1976年 | 1篇 |
1969年 | 1篇 |
1959年 | 1篇 |
排序方式: 共有439条查询结果,搜索用时 15 毫秒
1.
Moritoshi Yasunaga Noriyuki Aibe Yoshiki Yamaguchi Yorihisa Yamamoto Takaaki Awano Ikuo Yoshihara 《Artificial Life and Robotics》2008,12(1-2):219-222
Watching and tracking an object while seeing a much wider view is one of advantages of the eye system. We proposed and developed
a tracking camera system that mimics the eyes by using double-lens modules. In the system, a wide view is captured through
the wide-lens module, while the target in it is tracked and magnified through the telescopic lens module. Electronic circuits
for tracking control are implemented onto the reconfigurable VLSI or FPGA in order to embed the parallelism in the tracking
algorithm into the hardware. A successfully developed FPGA-based prototype performs high-speed tracking at the video-rate.
This work was present in part at the 12th International Symposium on Artificial Life and Robotics, Oita, Japan, January 25–27,
2007 相似文献
2.
Summary Hydroboration polymerization of various ,-dicyanoalkanes with thexylborane produced the corresponding poly(cyclodiborazane)s, that consist of boron-nitrogen four-membered rings. The structures of the obtained polymers were confirmed by spectroscopic analyses such as 1H-, 11B-NMR and IR spectra. From the result of thermogravimetric analysis of the polymer prepared from adiponitrile and thexylborane, 12% of the inorganic materials remained after heating at 900°C. *** DIRECT SUPPORT *** AEB03051 00003 相似文献
3.
Shuyan Gao Naoto Koshizaki Hideo Tokuhisa Emiko Koyama Takeshi Sasaki Jae‐Kwan Kim Joonghyun Ryu Deok‐Soo Kim Yoshiki Shimizu 《Advanced functional materials》2010,20(1):78-86
Colloidal Au‐amplified surface plasmon resonance (SPR), like traditional SPR, is typically used to detect binding events on a thin noble metal film. The two major concerns in developing colloidal Au‐amplified SPR lie in 1) the instability, manifested as a change in morphology following immersion in organic solvents and aqueous solutions, and 2) the uncontrollable interparticle distance, determining probe spacing and inducing steric hindrance between neighboring probe molecules. This may introduce uncertainties into such detecting techniques, degrade the sensitivity, and become the barricade hampering colloidal Au‐based transducers from applications in sensing. In this paper, colloidal Au‐amplified SPR transducers are produced by using ultrathin Au/Al2O3 nanocomposite films via a radio frequency magnetron co‐sputtering method. Deposited Au/Al2O3 nanocomposite films exhibit superior stability, and average interparticle distances between Au nanoparticles with similar average sizes can be tuned by changing surface coverage. These characteristics are ascribed to the spacer function and rim confinement of dielectric Al2O3 and highlight their advantages for application in optimal nanoparticle‐amplified SPR, especially when the probe size is smaller than the target molecule size. This importance is demonstrated here for the binding of protein (streptavidin) targets to the probe (biotin) surface. In this case, the dielectric matrix Al2O3 is a main contributor, behaving as a spacer, tuning the concentration of Au nanoparticles, and manipulating the average interparticle distance, and thus guaranteeing an appropriate number of biotin molecules and expected near‐field coupling to obtain optimal sensing performance. 相似文献
4.
We have studied the cathodoluminescence of AlxGa1-xAs/GaAs multilayers grown on ridge-type triangles by molecular beam epitaxy. The compositional variation of Al, as well as the distribution of impurity and/or defect, was revealed by variations in the cathodoluminescence spectra and images. The Al composition in an AlxGa1-xAs layer was highest in the (111)A facet and decreased in the order (100), (411)A, (111)-delta and (110) facets. On the other hand, the carbon concentration was highest in the (411)A facet and decreased in the order (111)A, (111)-delta, (100) and (110) facets. It should be noted that the (111)-delta facet has a significant effect on the redistribution of Al. Although our ridge-type triangles are rather large for the quantum structures, these data have elucidated the self-organization mechanism of the AlxGa1-xAs/GaAs system and have yielded information on the design of quantum structures. We conclude that cathodoluminescence observation is a powerful tool for studying the compositional variation or band structure of three-dimensional microscale or nanoscale construction. 相似文献
5.
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
6.
Y. Kawabata M. Utsuro S. Hayashi H. Yoshiki 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》1988,30(4):557-566
Concentrations and depth distributions of the surface hydrogen and the surface deuterium in vacuum evaporated nickel layers and beryllium plates have been investigated by the ERDA method. It is shown that if the evaporation vacuum pressure is kept better than 10−6 Torr, the hydrogen adsorption from the residual gas during the evaporation is negligible and the hydrogen from residual or atmospheric gases after the evaporation is the main source of the surface hydrogen. Commercial beryllium plates are found to have surface hydrogen of about 1016 atoms cm2. Deuterium treated samples, either in D2 gas or heavy water, do not show more than possibly a partial replacement of hydrogen. The influence of substrates is small if the thickness of the evaporated nickel layer is more than 2000 Å. The measurements are in good agreement with previously published results. 相似文献
7.
8.
9.
Toshiyuki Iguchi Sakae Takenaka Keizo Nakagawa Yoshiki Orita Hideki Matsune Masahiro Kishida 《Topics in Catalysis》2009,52(6-7):563-570
Formation of carbon nanofibers (CNFs) and carbon nanotubes (CNTs) through the decomposition of ethylene at 973 K was achieved using various metal catalysts covered with silica layers. CNFs of various diameters were formed by ethylene decomposition over a Co metal catalyst supported on the outer surface of the silica. In contrast, silica-coated Co catalysts formed CNTs with uniform diameters by ethylene decomposition. Silica-coated Ni/SiO2 and Pt/carbon black also formed CNTs with uniform diameters, while CNFs and CNTs with various diameters were formed over Ni/SiO2 and Pt/carbon black without a silica coating. These results indicate that silica layers that envelop metal particles prevent sintering of the metal particles during ethylene decomposition. This results in the preferential formation of CNTs with a uniform diameter. 相似文献
10.
Summary Organoboron copolymers were prepared by polyaddition of diene mixture or diene/diyne mixture, respectively, with thexylborane (1). When a mixture of dienes such as 1,2-diallyloxyethane (2a) and p-diallylbenzene (2b) was polymerized with 1, the peaks in GPC using both UV and RI detectors were shifted to higher molecular weight regions with the increase of the amount of 1. The molecular weight distribution of the copolymer obtained by this method indicated clear difference from that of a mixture of two homopolymers. On the other hand, when the poymerization between 1 and 1,7-octadiene (2c) was carried out in the presence of a trace amount of 1,7-octadiyne (4), the molecular weights of organoboron polymers were found to be increased when the ratio of 4/2c was increased. 相似文献