全文获取类型
收费全文 | 863篇 |
免费 | 81篇 |
国内免费 | 1篇 |
专业分类
电工技术 | 18篇 |
综合类 | 3篇 |
化学工业 | 185篇 |
金属工艺 | 27篇 |
机械仪表 | 60篇 |
建筑科学 | 6篇 |
矿业工程 | 1篇 |
能源动力 | 26篇 |
轻工业 | 56篇 |
水利工程 | 2篇 |
石油天然气 | 1篇 |
无线电 | 167篇 |
一般工业技术 | 239篇 |
冶金工业 | 71篇 |
原子能技术 | 10篇 |
自动化技术 | 73篇 |
出版年
2024年 | 2篇 |
2023年 | 17篇 |
2022年 | 12篇 |
2021年 | 31篇 |
2020年 | 21篇 |
2019年 | 32篇 |
2018年 | 36篇 |
2017年 | 32篇 |
2016年 | 51篇 |
2015年 | 26篇 |
2014年 | 51篇 |
2013年 | 58篇 |
2012年 | 78篇 |
2011年 | 68篇 |
2010年 | 69篇 |
2009年 | 40篇 |
2008年 | 49篇 |
2007年 | 33篇 |
2006年 | 24篇 |
2005年 | 22篇 |
2004年 | 20篇 |
2003年 | 21篇 |
2002年 | 12篇 |
2001年 | 11篇 |
2000年 | 16篇 |
1999年 | 14篇 |
1998年 | 15篇 |
1997年 | 15篇 |
1996年 | 12篇 |
1995年 | 8篇 |
1994年 | 9篇 |
1993年 | 7篇 |
1992年 | 2篇 |
1991年 | 4篇 |
1990年 | 6篇 |
1989年 | 5篇 |
1988年 | 3篇 |
1987年 | 6篇 |
1986年 | 4篇 |
1984年 | 3篇 |
排序方式: 共有945条查询结果,搜索用时 296 毫秒
941.
Jeong-Chan Lee Yeonju Noh Nam-Su Kim Ki Beom Park Hyunghoon Kim Hyung-Hwan Cho Hyung-Ki Park Tea-Sung Jun Chang-Soo Park 《国际钢铁研究》2023,94(2):2200243
The austenitic stainless steel's remarkable mechanical properties are caused by twinning-induced plasticity and transformation-induced plasticity mechanisms. Numerous studies focus on stacking fault energy's effect, which is affected by various factors, to interpret and control these mechanisms. However, crystallographic orientation is also an important parameter for mechanical properties in metals. This study compares the mechanical properties and microstructural features of 304 austenitic stainless steel, focusing on the effect of initial texture and deformation temperature. Microstructural characterization is identified by an interrupted tensile test based on strain, tensile direction, and temperature conditions, and X-ray diffraction and electron back-scattered diffraction analysis are performed. The results show that the mechanical features and strain-induced martensitic transformation rate depend on the tensile directions. In addition, this trend is maintained irrespective of the temperature conditions. The attribute reason is that the difference in the Taylor factor and the formation rate of the deformed band structure is induced by the initial crystallographic orientations. Moreover, a decrease in temperature significantly increases the dislocation densities and abundant twins and transformed martensites formation. Furthermore, the yield and tensile strengths are enhanced while the elongation decreased with the tensile strains. 相似文献
942.
Henok Getachew Girma Kwang Hun Park Dongseob Ji Yejin Kim Hye Min Lee Seungju Jeon Seo-Hyun Jung Jin Young Kim Yong-Young Noh Bogyu Lim 《Advanced functional materials》2023,33(18):2213381
Although semiconducting single-walled carbon nanotubes (sc-SWNTs) exhibit excellent sensing properties for various gases, commercialization is hampered by several obstacles. Among these, the difficulty in reproducibly fabricating sc-SWNT films with uniform density and thickness is the main one. Here, a facile fabrication method for sc-SWNT-based hydrogen (H2) sensors with excellent reproducibility, high sensitivity, and selectivity against CO, CO2, and CH4 is reported. Uniform-density and monolayer sc-SWNT films are fabricated using chemical immobilized through the click reaction between azide-functionalized polymer-wrapped sc-SWNTs and immobilized alkyne polymer on a substrate before decorating with Pd nanoparticles (0.5–3.0 nm). The optimized sc-SWNT sensor has a high room-temperature response of 285 with the response and recovery times of 10 and 3 s, respectively, under 1% H2 gas in air. In particular, this sensor demonstrates highly selective H2 detection at room temperature (25 °C), compared to other gases and humidity. Therefore, the chemical immobilization of the monolayer SWNT films with reproducible and uniform density has the potential for large-scale fabrication of robust room-temperature H2 sensors. 相似文献
943.
Ji-Young Go Gwon Byeon Taesu Choi Shuzhang Yang Wenwu Li Yong-Young Noh 《Advanced functional materials》2023,33(44):2303759
Metal halide perovskite optoelectronic devices have made significant progress over the past few years, but precise control of charge carrier density through doping is essential for optimizing these devices. In this study, the potential of using an organic salt, N,N-dimethylanilinium tetrakis(pentafluorophenyl)borate, as a dopant for Sn-based perovskite devices, is explored. Under optimized conditions, the thin film transistors based on the doped 2D/3D perovskite PEAFASnI3 demonstrate remarkable improvement in hole mobility, reaching 7.45 cm2V−1s−1 with a low subthreshold swing and the smallest sweep hysteresis (ΔVhysteresis = 2.27 V) and exceptional bias stability with the lowest contact resistance (2.2 kΩ cm). The bulky chemical structure of the dopant prevents it from penetrating the perovskite lattice and also surface passivation against Sn oxidation due to its hydrophobic nature surface. This improvement is attributed to the bifunctional effect of the dopant, which simultaneously passivates defects and improves crystal orientation. These findings provide new insights into potential molecular dopants that can be used in metal halide perovskite devices. 相似文献
944.
Wonryeol Yang Geonwoong Park Ao Liu Hock Beng Lee Jae-Wook Kang Huihui Zhu Yong-Young Noh 《Advanced functional materials》2023,33(36):2303309
2D tin-based perovskites have gained considerable attention for use in diverse optoelectronic applications, such as solar cells, lasers, and thin-film transistors (TFTs), owing to their good stability and optoelectronic properties. However, their intrinsic charge-transport properties are limited, and the insulating bulky organic ligands hinder the achievement of high-mobility electronics. Blending 3D counterparts into 2D perovskites to form 2D/3D hybrid structures is a synergistic approach that combine the high mobility and stability of 3D and 2D perovskites, respectively. In this study, reliable p-channel 2D/3D tin-based hybrid perovskite TFTs comprising 3D formamidinium tin iodide (FASnI3) and 2D fluorinated 4-fluoro-phenethylammonium tin iodide ((4-FPEA)2SnI4) are reported. The optimized FPEA-incorporated TFTs show a high hole mobility of 12 cm2 V−1 s−1, an on/off current ratio of over 108, and a subthreshold swing of 0.09 V dec−1 with negligible hysteresis. This excellent p-type characteristic is compatible with n-type metal-oxide TFT for constructing complementary electronics. Two procedures of antisolvent engineering and device patterning are further proposed to address the key concern of low-performance reproducibility of perovskite TFTs. This study provides an alternative A-cation engineering method for achieving high-performance and reliable tin-halide perovskite electronics. 相似文献
945.
Virtual Reality - Cybersickness is one of the greatest barriers to the adoption of virtual reality. A growing body of research has focused on identifying the characteristics of cybersickness and... 相似文献