全文获取类型
收费全文 | 753篇 |
免费 | 17篇 |
国内免费 | 1篇 |
专业分类
电工技术 | 49篇 |
综合类 | 1篇 |
化学工业 | 198篇 |
金属工艺 | 17篇 |
机械仪表 | 18篇 |
建筑科学 | 9篇 |
能源动力 | 63篇 |
轻工业 | 99篇 |
水利工程 | 1篇 |
无线电 | 53篇 |
一般工业技术 | 124篇 |
冶金工业 | 83篇 |
原子能技术 | 25篇 |
自动化技术 | 31篇 |
出版年
2023年 | 2篇 |
2022年 | 7篇 |
2021年 | 12篇 |
2020年 | 6篇 |
2019年 | 3篇 |
2018年 | 16篇 |
2017年 | 11篇 |
2016年 | 6篇 |
2015年 | 6篇 |
2014年 | 16篇 |
2013年 | 38篇 |
2012年 | 20篇 |
2011年 | 43篇 |
2010年 | 23篇 |
2009年 | 44篇 |
2008年 | 33篇 |
2007年 | 33篇 |
2006年 | 37篇 |
2005年 | 30篇 |
2004年 | 22篇 |
2003年 | 27篇 |
2002年 | 30篇 |
2001年 | 23篇 |
2000年 | 18篇 |
1999年 | 22篇 |
1998年 | 46篇 |
1997年 | 15篇 |
1996年 | 23篇 |
1995年 | 15篇 |
1994年 | 16篇 |
1993年 | 9篇 |
1992年 | 11篇 |
1991年 | 8篇 |
1990年 | 10篇 |
1989年 | 8篇 |
1988年 | 5篇 |
1987年 | 11篇 |
1986年 | 16篇 |
1985年 | 8篇 |
1984年 | 6篇 |
1983年 | 13篇 |
1982年 | 6篇 |
1981年 | 3篇 |
1978年 | 3篇 |
1977年 | 2篇 |
1976年 | 4篇 |
1974年 | 1篇 |
1973年 | 1篇 |
1972年 | 1篇 |
1965年 | 1篇 |
排序方式: 共有771条查询结果,搜索用时 31 毫秒
1.
Noriyuki Wada Jyoji Hanai Mikiya Furukawa Kazuo Kojima 《Journal of the American Ceramic Society》2019,102(8):4621-4631
To make a Mn2+-doped red glass phosphor that can be excited with ultraviolet (UV) light of light-emitting diodes (LEDs), 60P2O5-35ZnO-5Al2O3-8MnO-xCu2O glasses (x = 0-1.00) were prepared by a melt-quenching method at 1200-1400°C for 30-180 minutes in atmospheric air, and the redox of Mn and Cu as well as fluorescence properties were investigated. The Mn2+ ion was not reduced and oxidized in the melting, quenching, and annealing processes. The valence of Cu in the glasses changed in the order of 0, 1+, and 2+ with the increase in the amount of Cu2O and in the melting temperature and time. In this study, a 60P2O5-35ZnO-5Al2O3-8MnO-0.10Cu2O glass melted at 1250°C for 90 minutes, having the highest Cu+ concentration, showed the strongest Mn2+ red fluorescence under the UV light at 275 nm. This strong Mn2+ red fluorescence has been caused by the energy transfer from excited Cu+ ions to Mn2+ ions. 相似文献
2.
Shizuo Arichi Noriyuki Sakamoto Shozo Himuro Mayumi Miki Masafumi Yoshida 《Polymer》1985,26(8):1175-1180
In order to obtain the additional data concerning the unperturbed dimension of poly-4-substituted styrene, light scattering measurements are performed on the twenty-two fractions with molecular weight of (0.91–352)·104 of poly(4-acetoxystyrene) in dioxan at 25°C, from which the molecular weight obtained was found easily to be evaluated with the gel permeation chromatography using THF. Phase separation experiments for this polymer indicate that the theta state is attained in isopropyl acetate at 19.7°C and butyl acetate at 26.8°C. By making viscosity measurements at that state, the value of KΘ is directly evaluated as 5.4·10?4 dl g?1. The limiting viscosity number is also obtained in good solvents, THF and dioxan, at 25°C and constants of the Mark-Houwink-Sakurada equation in each solvent are determined. Further, approximately the same KΘ as above is obtained from these data with the Stockmayer-Fixman plot. The calculated value of steric factor, 2.37, on this polymer may be plausible, compared with those of polyvinylaromatic derivatives. 相似文献
3.
ABSTRACT Postmortem structural changes in titin and nebulin filaments were investigated by incubating isolated myofibrils in a solution containing 0.1 mM calcium ions and various concentrations of a protease inhibitor. The inhibition curves showed 2 abnormal steps with increases in the concentration of leupeptin or calpastatin domain I. While the amounts of unchanged titin and nebulin were constant in the 1st step, the 2nd occurred at higher protease inhibitor concentrations. These facts indicated that excess amounts of leupeptin and calpastatin domain I caused deterioration in titin and nebulin properties, thus interfering with the binding of calcium ions. We concluded that the severance of titin and nebulin filaments in the 1st step were induced by calcium ions at 0.1 mM. 相似文献
4.
Gong-Liang Li Ishihara Tatsumi Moro-oka Yoshihiko Takita Yusaku 《Applied catalysis. B, Environmental》1996,9(1-4):239-249
The catalytic decomposition of CHClF2 was studied over various acidic metal oxides in a fixed-bed reactor. The Cr2O3ZrO2 exhibited the highest activity. The presence of water vapor in the reaction system suppresses the transformation of oxides to fluorides, progresses the formation of CO2, and it improves the catalysts life. 相似文献
5.
Noda K. Tatsumi T. Uchida T. Nakajima K. Miyamoto H. Chenming Hu 《Electron Devices, IEEE Transactions on》1998,45(4):809-814
A simple fabrication technology for delta-doped MOSFETs, named post-low-energy implanting selective epitaxy (PLISE) is presented. The PLISE technology needs no additional photo-lithography mask, deposition step or etching step even for CMOS devices. The only additional step is growing undoped epitaxial channel layers by UHV-CVD after the channel implantation. With this technology, delta-doped NMOSFETs with 0.1-μm gate length were successfully fabricated. By optimizing the epi-layer thickness and the channel doping level, short-channel effects are suppressed enough to achieve 0.1-μm gate length. Moreover, the junction capacitance at zero bias is reduced by 50% 相似文献
6.
Shuzo Ueda Ryoichi Kurihara Noriyuki Miyazaki Toshikuni Isozaki 《International Journal of Pressure Vessels and Piping》1985,18(3):161-176
The purpose of pipe rupture studies in JAERI is to perform model tests on pipe whip, restraint behavior, jet impingement and jet thrust force, and to establish a computational method for analyzing these phenomena. This report presents the analytical results of 4-inch pipe whip tests under BWR LOCA conditions.Dynamic response analyses were performed using the general-purpose finite element program ADINA. The test pipe was modelled by straight beam elements and the four restraints were modelled by a single truss element. The analytical results were compared with the experimental results. Impact time and maximum total restraint force showed good agreement with experimental results. On the other hand, pipe strain and pipe deflection could not be predicted so well. The reason for this is that the sliding of the restraint during the pipe whip movement cannot be considered in the analyses. 相似文献
7.
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
8.
9.
10.