Author Keywords: Radiation detection; Long-lasting phosphor; Luminescence; Temperature dependence; Fade-out effect 相似文献
全文获取类型
收费全文 | 1260篇 |
免费 | 71篇 |
国内免费 | 6篇 |
专业分类
电工技术 | 70篇 |
综合类 | 4篇 |
化学工业 | 312篇 |
金属工艺 | 40篇 |
机械仪表 | 26篇 |
建筑科学 | 40篇 |
能源动力 | 52篇 |
轻工业 | 140篇 |
水利工程 | 9篇 |
石油天然气 | 3篇 |
无线电 | 112篇 |
一般工业技术 | 273篇 |
冶金工业 | 71篇 |
原子能技术 | 41篇 |
自动化技术 | 144篇 |
出版年
2023年 | 6篇 |
2022年 | 34篇 |
2021年 | 48篇 |
2020年 | 23篇 |
2019年 | 38篇 |
2018年 | 30篇 |
2017年 | 29篇 |
2016年 | 45篇 |
2015年 | 42篇 |
2014年 | 65篇 |
2013年 | 81篇 |
2012年 | 87篇 |
2011年 | 128篇 |
2010年 | 82篇 |
2009年 | 77篇 |
2008年 | 89篇 |
2007年 | 66篇 |
2006年 | 38篇 |
2005年 | 48篇 |
2004年 | 41篇 |
2003年 | 32篇 |
2002年 | 25篇 |
2001年 | 17篇 |
2000年 | 12篇 |
1999年 | 5篇 |
1998年 | 33篇 |
1997年 | 23篇 |
1996年 | 17篇 |
1995年 | 5篇 |
1994年 | 9篇 |
1993年 | 12篇 |
1992年 | 6篇 |
1991年 | 3篇 |
1990年 | 4篇 |
1989年 | 3篇 |
1987年 | 2篇 |
1986年 | 2篇 |
1985年 | 1篇 |
1984年 | 4篇 |
1983年 | 6篇 |
1982年 | 2篇 |
1981年 | 2篇 |
1980年 | 1篇 |
1978年 | 1篇 |
1977年 | 3篇 |
1976年 | 1篇 |
1975年 | 2篇 |
1974年 | 3篇 |
1972年 | 2篇 |
1969年 | 1篇 |
排序方式: 共有1337条查询结果,搜索用时 109 毫秒
1.
The present paper includes experimental and analytical data on the fracture properties of a nickel-iron superalloy, a ferromagnetic austenite, at 4 K in magnetic fields of 0 and 6 T. The tensile, notch tensile and small punch tests are employed. A finite element analysis is also performed to convert the experimentally measured load-displacement data into useful engineering information. To interpret the results we review the available theory of the influence of magnetic field on the stress intensity factor for a crack in ferromagnetic materials. 相似文献
2.
3.
Critical heat fluxes (CHFs) were measured for two types of rectangular ducts containing horizontal flat plate heaters. One has the flat plate heater of 6 mm wide and 20 mm long located on the inner lower wall at 50 mm from the inlet. The other duct has two horizontal flat plates of 6 mm wide and 20 mm long on inner upper and lower walls at 50 mm from the inlet. The equation of CHF for the forced convection containing a new nondimensional-parameter m introduced in order to calculate cross-sectionally averaged liquid temperature at the center of the duct was derived based on two fluid model, ordinary convection theorem and experimental results. It was confirmed that this correlation can describe not only the author's data on the duct but also other worker's data for channels with different shapes and sizes. 相似文献
4.
Akira Watanabe Yoshimitsu Takeuchi Goji Saeki 《Journal of the American Ceramic Society》1985,68(11):308-C
The length of potassium titanate fibers produced by several conventional methods averages 50 μm, with a maximum of 100 μm. Extremely long fibers (most >1000 μm long) were obtained by calcination in N2 gas flowing at 5.2×10-4 m/s. 相似文献
5.
Munehiko Kowatari Daisuke Koyama Yoshiyuki Satoh Kouichi Iinuma Shunsuke Uchida 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》2002,480(2-3):431-439
The temperature dependence of luminescence from a long-lasting phosphor (LLP), SrAl2O4 : Eu2+,Dy3+, exposed to ionizing radiation has been measured to understand the LLP luminescence mechanism. Evaluation of the decay constants of the LLP exposed to -, β- or γ-rays at temperatures from 200 to 390 K showed that the decay constant is divided into four components ranging from 10−4 to 10−1 s−1 with activation energies of 0.02–0.35 eV.
Total luminous intensity from the LLP with changing irradiation temperature has its maximum value around the room temperature. Irradiation at elevated temperature (390 K) has the total luminescence pattern with monotonous decrease as temperature rises. As a result of evaluating the temperature dependence of luminescence, the luminescence mechanism is considered as follows:
6.
K Iihara M Sasahara Y Saeki N Hashimoto H Kikuchi F Hazama 《Canadian Metallurgical Quarterly》1993,20(7-8):515-521
1. We characterized the endothelial cell-derived growth factors of SHRSP and Wistar Kyoto rats (WKY), respectively and found that platelet-derived growth factor (PDGF)-B chain related growth factor constituted a major portion of the mitogenic activity of the conditioned media of endothelial cells from both animals. There were no remarkable qualitative differences between the endothelial cell-derived growth factors of SHRSP and WKY. 2. Northern analysis revealed that the expression of PDGF-B chain was 2-4-fold enhanced in cultured aortic endothelial cells of SHRSP. This enhanced expression of PDGF-B chain, which may be induced under chronic hypertensive conditions, is suggested to contribute to the increase in endothelial cell-derived growth factors reported in this animal. 相似文献
7.
The light scattering from the spherulites of polyethylene terephthalate grown near the glass transition temperature has been investigated. The Hv scattering profiles can be reproduced by the sum of the ideal spherulite scattering with the distribution of spherulite radius and the isotropic scattering from randomly oriented crystallites. The ratio of optical anisotropies in the isotropic scattering to the ideal spherulite scattering is obtained by the method established to eliminate the effects of the number density of spherulites and the coefficient depending on the experimental conditions. It is found that the anisotropy ratio is almost independent of the crystallization time and of temperature above 106 °C, while it is larger at a crystallization temperature of 103 °C. The spherulitic structure is discussed in terms of the anisotropy ratio. 相似文献
8.
Properties of Stabilizing PID Gain Set in Parameter Space 总被引:1,自引:0,他引:1
The properties of the PID gain set for which all the closed-loop poles lie in the left half of the complex plane are examined on the parameter plane. A new method of determining the increase in the number of unstable poles when the gain crosses the boundary of stability regions is proposed. This method is useful for determining the number of unstable poles in each region. These results are extended to Gamma-stability based on conformal mapping. 相似文献
9.
T Kuroda M Saeki K Tanaka M Komura T Honna M Nakano M Sugiyama S Nakagawa K Miyasaka 《Canadian Metallurgical Quarterly》1998,33(11):1641-1644
BACKGROUND/PURPOSE: To develop practical and less invasive techniques for fetal endoscopic surgery, new methods of lifting the uterine wall to allow fetal surgery without maternal laparotomy were developed and assessed. METHODS: Fetal endoscopic surgical procedures, including tracheostomy and umbilical vascular cannulation, were performed using one of the three methods to enter the uterus without maternal laparotomy in pregnant goats (n = 6; 105 to 115 days' gestation): (1) direct uterine lifting with an air-cushion device; (2) indirect uterine lifting, in which the uterine wall was fixed to the maternal abdominal wall using balloon tip ports inserted percutaneously by Seldinger's method, then the maternal abdomen was lifted mechanically; and (3) combined method, in which low pressure CO2 (5 mm Hg for initial inflation and 2 mm Hg for maintenance) was insufflated into the uterus in addition to the indirect uterine lifting cited above. RESULTS: The direct uterine lifting caused massive injury of myometrium and uterine membranes. The creation of intrauterine space and the protection of the membranes were not accomplished effectively by the indirect uterine lifting only. The combined method provided the adequate intrauterine space and excellent endoscopic visibility for completion of the endoscopic procedures with minimal uterine injury. CONCLUSION: The fetal endoscopic surgery may be accomplished simply and safely by the combined method, a novel technique of uterine lifting to allow fetal surgery without maternal laparotomy. 相似文献
10.
Asia boasts a growing software industry spread across several countries. However, software technology in Asia still lags behind the US. To become competitive in the global marketplace, many Asian countries have started to improve their university systems and software-development industries. If successful, by 2001 their efforts will create an Asian software industry quite different from today's. The authors survey these efforts and sketch briefly the history of software development in each country. They survey recent trends in Asian software engineering from the industrial, educational, and organizational viewpoints, and offer an optimistic assessment of efforts toward modernization and regional cooperation 相似文献