全文获取类型
收费全文 | 560篇 |
免费 | 9篇 |
国内免费 | 4篇 |
专业分类
电工技术 | 13篇 |
综合类 | 1篇 |
化学工业 | 109篇 |
金属工艺 | 19篇 |
机械仪表 | 7篇 |
建筑科学 | 8篇 |
能源动力 | 25篇 |
轻工业 | 27篇 |
水利工程 | 7篇 |
无线电 | 56篇 |
一般工业技术 | 125篇 |
冶金工业 | 146篇 |
原子能技术 | 8篇 |
自动化技术 | 22篇 |
出版年
2023年 | 3篇 |
2022年 | 5篇 |
2021年 | 16篇 |
2020年 | 4篇 |
2019年 | 11篇 |
2018年 | 4篇 |
2017年 | 5篇 |
2016年 | 6篇 |
2015年 | 6篇 |
2014年 | 10篇 |
2013年 | 15篇 |
2012年 | 11篇 |
2011年 | 34篇 |
2010年 | 12篇 |
2009年 | 19篇 |
2008年 | 21篇 |
2007年 | 16篇 |
2006年 | 15篇 |
2005年 | 18篇 |
2004年 | 12篇 |
2003年 | 21篇 |
2002年 | 13篇 |
2001年 | 10篇 |
2000年 | 10篇 |
1999年 | 13篇 |
1998年 | 51篇 |
1997年 | 37篇 |
1996年 | 32篇 |
1995年 | 14篇 |
1994年 | 18篇 |
1993年 | 16篇 |
1992年 | 9篇 |
1991年 | 12篇 |
1990年 | 8篇 |
1989年 | 12篇 |
1988年 | 4篇 |
1987年 | 4篇 |
1986年 | 4篇 |
1985年 | 6篇 |
1984年 | 4篇 |
1983年 | 2篇 |
1982年 | 6篇 |
1981年 | 3篇 |
1980年 | 4篇 |
1977年 | 5篇 |
1976年 | 7篇 |
1975年 | 1篇 |
1974年 | 1篇 |
1973年 | 1篇 |
1972年 | 1篇 |
排序方式: 共有573条查询结果,搜索用时 234 毫秒
41.
42.
43.
44.
In 35 lower limbs of 22 patients with peripheral circulation disturbance, we evaluated the effects of lumbar sympathetic ganglion block (LSGB) by skin temperature difference (delta T) between the two measured by thermography before and after LSGB. We divided the patients into two groups; ASO group (n = 15): patients with chronic arterial occulusive diseases, and nonASO group (n = 7): those with peripheral circulation disturbance partly due to decrease nervous function. After LSGB, we recognized a significant increase in delta T and remission of ischemic symptoms in all the patients of nonASO group and those in early stage of ASO group. This suggests that in ASO group LSGB should be applied as soon as possible to obtain good outcome, and thermography is useful to evaluate the effects of LSGB in patients with peripheral circulation disturbance of the lower limbs. 相似文献
45.
F. Ono S. Komatsu Y. Chimi N. Ishikawa A. Iwase T. Kambara 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2005,230(1-4):279-283
High-energy ion irradiation was performed using a ring-cyclotron installed at the Institute of Physical and Chemical Research (RIKEN). The incident ions were Ta with the energy of 3.71 GeV, and the fluence was fixed to 5 × 1012 ions/cm2. As a target, three sheets of square plates of Fe–30.2 at.% Ni invar alloys were put one upon another. The shift of the Curie temperature TC of the first sample was 14 K, while that of the second one was 22 K. Comparing these two, the shift was as large as 46 K in the last sample in which ions stopped in the middle. It was concluded that there are at least two different mechanisms that contribute to the shift of TC. 相似文献
46.
47.
Pradyumna Gupta Himanshu Jain David B. Williams Tsuyoshi Honma Yasuhiko Benino Takayuki Komatsu 《Journal of the American Ceramic Society》2008,91(1):110-114
Using a novel, selective heating by Nd:YAG laser, a single-crystal architecture is created in a model glass system, Sm0.5 La0.5 BGeO5 , which devitrifies congruently into a ferroelectric phase of the same composition as the parent glass. The Sm3+ ions in glass absorb the light and heat the matrix locally resulting in devitrification. Initially, a polycrystalline spot is formed. However, with optimum laser power, scanning speed, and the depth of focus, one of the grains acts as the seed for further growth as a single crystal. By programming the relative displacement of the glass with respect to laser spot, desired single ferroelectric crystal architecture is created. The optical functionalities (guiding of light and second harmonic generation) of the architectures are shown, which demonstrate the viability of this method for constructing active elements in optical integrated circuits. The single-crystal nature of the architecture is confirmed from the electron backscattered diffraction results. 相似文献
48.
Full-scale application of anaerobic digestion process with partial ozonation of digested sludge. 总被引:4,自引:0,他引:4
For improving sludge digestion and biogas recovery, a new anaerobic digestion process combined with ozonation was tested at a full-scale unit for 2 years and its performance was compared with a simultaneously operated conventional anaerobic digestion process. The new process requires two essential modifications, which includes ozonation for enhancing the biological degradability of sludge organics and concentrating of solids in the digester through a solid/liquid separation for extension of SRT. These modifications resulted in high VSS degradation efficiency of ca. 88%, as much as 1.3 times of methane production and more than 70% reduction in dewatered sludge cake production. Owing to accumulation of inorganic solids in the digested sludge, water content of the dewatered sludge cake also reduced from 80% to 68%. An energy analysis suggested that no supplemental fuel was necessary for the subsequent incineration of the cake from the new process scheme. The process is suitable to apply to a low-loaded anaerobic digestion tank, where power production is used. 相似文献
49.
The influence of HfO2 addition on the fracture strength and microstructure of ß-SiAlON ceramics sintered from Si3 N4 and Al2 O3 powders was investigated. The strength was increased by the addition of HfO2 , from ∼500 MPa to 700 MPa, and was almost constant from ambient temperature to 1300°C. Monoclinic HfO2 grains that were distributed in the SiAlON grain boundaries had a flat shape (∼20 nm thick) and were surrounded by an amorphous phase. The aluminum concentration in ß-SiAlON in the samples with an Al2 O3 starting composition of 15 wt% was decreased by the addition of HfO2 . The amount of secondary phases was very small at grain boundaries between the SiAlON grains; amorphous phases were observed infrequently at the triple points but were very small (∼20 nm). The effects of HfO2 addition on the mechanism of the microstructure development and fracture strength are discussed. 相似文献
50.
Matsumoto Mitsutaka Komatsu Shingo 《The International Journal of Advanced Manufacturing Technology》2015,78(1-4):161-175
The International Journal of Advanced Manufacturing Technology - Remanufacturing is effective for energy and material savings; however, production planning and control in remanufacturing are more... 相似文献