全文获取类型
收费全文 | 411篇 |
免费 | 28篇 |
专业分类
电工技术 | 6篇 |
化学工业 | 118篇 |
金属工艺 | 7篇 |
机械仪表 | 10篇 |
建筑科学 | 2篇 |
能源动力 | 8篇 |
轻工业 | 28篇 |
无线电 | 46篇 |
一般工业技术 | 158篇 |
冶金工业 | 35篇 |
原子能技术 | 5篇 |
自动化技术 | 16篇 |
出版年
2024年 | 1篇 |
2023年 | 3篇 |
2022年 | 11篇 |
2021年 | 13篇 |
2020年 | 7篇 |
2019年 | 10篇 |
2018年 | 7篇 |
2017年 | 8篇 |
2016年 | 7篇 |
2015年 | 12篇 |
2014年 | 14篇 |
2013年 | 17篇 |
2012年 | 24篇 |
2011年 | 37篇 |
2010年 | 22篇 |
2009年 | 26篇 |
2008年 | 26篇 |
2007年 | 18篇 |
2006年 | 15篇 |
2005年 | 31篇 |
2004年 | 19篇 |
2003年 | 14篇 |
2002年 | 10篇 |
2001年 | 10篇 |
2000年 | 6篇 |
1999年 | 7篇 |
1998年 | 14篇 |
1997年 | 7篇 |
1996年 | 4篇 |
1995年 | 2篇 |
1994年 | 3篇 |
1993年 | 2篇 |
1992年 | 2篇 |
1991年 | 2篇 |
1990年 | 4篇 |
1989年 | 4篇 |
1988年 | 8篇 |
1987年 | 3篇 |
1986年 | 2篇 |
1985年 | 1篇 |
1984年 | 3篇 |
1983年 | 1篇 |
1982年 | 1篇 |
1980年 | 1篇 |
排序方式: 共有439条查询结果,搜索用时 0 毫秒
61.
Dai‐Ming Tang Cui‐Lan Ren Ling Zhang Ying Tao Peng Zhang Wei Lv Xiang‐Ling Jia Xiaojuan Jiang Guangmin Zhou Takahito Ohmura Ping Huai Feng Li Yoshio Bando Dmitri Golberg Quan‐Hong Yang 《Advanced functional materials》2019,29(19)
It is essential to understand the size scaling effects on the mechanical properties of graphene networks to realize the potential mechanical applications of graphene assemblies. Here, a “highly dense‐yet‐nanoporous graphene monolith (HPGM)” is used as a model material of graphene networks to investigate the dependence of mechanical properties on the intrinsic interplanar interactions and the extrinsic specimen size effects. The interactions between graphene sheets could be enhanced by heat treatment and the plastic HPGM is transformed into a highly elastic network. A strong size effect is revealed by in situ compression of micro‐ and nanopillars inside electron microscopes. Both the modulus and strength are drastically increased as the specimen size reduces to ≈100 nm, because of the reduced weak links in a small volume. Molecular dynamics simulations reveal the deformation mechanism involving slip‐stick sliding, bending, buckling of graphene sheets, collapsing, and densification of graphene cells. In addition, a size‐dependent brittle‐to‐ductile transition of the HPGM nanopillars is discovered and understood by the competition between volumetric deformation energy and critical dilation energy. 相似文献
62.
Muhammad Iqbal Yusuf Valentino Kaneti Jeonghun Kim Brian Yuliarto Yong‐Mook Kang Yoshio Bando Yoshiyuki Sugahara Yusuke Yamauchi 《Small (Weinheim an der Bergstrasse, Germany)》2019,15(6)
Palladium (Pd) plays an important role in numerous catalytic reactions, such as methanol and ethanol oxidation, oxygen reduction, hydrogenation, coupling reactions, and carbon monoxide oxidation. Creating Pd‐based nanoarchitectures with increased active surface sites, higher density of low‐coordinated atoms, and maximized surface coverage for the reactants is important. To address the limitations of pure Pd, various Pd‐based nanoarchitectures, including alloys, intermetallics, and supported Pd nanomaterials, have been fabricated by combining Pd with other elements with similar or higher catalytic activity for many catalytic reactions. Herein, recent advances in the preparation of Pd‐based nanoarchitectures through solution‐phase chemical reduction and electrochemical deposition methods are summarized. Finally, the trend and future outlook in the development of Pd nanocatalysts toward practical catalytic applications are discussed. 相似文献
63.
A novel metal-insulator heterostructure made of twinned Ga2O3 nanowires embedding discrete gold particles along the twin boundary was formed through a reaction between gold, gallium, and silica at 800 degrees C during simple thermal annealing. The Au-in-Ga2O3 peapods spontaneously crystallized under phase separation induced by the formation of twin boundaries. The nanostructures were analyzed by field emission scanning (FESEM) and transmission electron microscopes (FETEM), and their photoresponse was investigated using a double-frequency Nd:YAG laser with a wavelength of 532 nm on a designed single-nanowire device. The surface plasmon resonance (SPR) effects of embedded Au nanoparticles are proposed to be responsible for the remarkable photoresponse of these novel structures. 相似文献
64.
Takahiro Wada Yuichiro Manabe Issei Nakamura Yuichi Tsunoyama Hiroo Nakajima Masako Bando 《Journal of Nuclear Science and Technology》2016,53(11):1824-1830
We have investigated the dependence of the mutation frequency on the dose and dose rate of artificial radiation using the Whack-A-Mole (WAM) model that we recently proposed. In particular, we pay special attention to the case of long-term and low-dose-rate exposure. Our results indicate that the WAM model successfully describes the dose-rate dependence, and it can replace the so-called dose and dose-rate effectiveness factor (DDREF), which has been used for long, to account for the differences between high-dose-rate and low-dose-rate data. The basic properties of the WAM model are discussed with special emphasis on the dose-rate dependence in order to demonstrate how the dose-rate dependence, which is built into the model explicitly, plays a key role. Biological effects of long-term exposure to extremely low-dose-rate radiation are discussed in light of analysis of mega-mouse experiments using the WAM model. In the WAM model, the effects of long-term exposure show a saturation property, thus making it distinctly different from the ‘linear no threshold (LNT)’ hypothesis that predicts a linear increase of the effects with time. 相似文献
65.
Effect of collagen fibril formation on bioresorbability of hydroxyapatite/collagen composites 总被引:2,自引:0,他引:2
Yunoki S Marukawa E Ikoma T Sotome S Fan H Zhang X Shinomiya K Tanaka J 《Journal of materials science. Materials in medicine》2007,18(11):2179-2183
Porous hydroxyapatite/collagen (HAp/Col) composite is a promising biomaterial and a scaffold for bone tissue engineering.
The effect of fibril formation of Col in the porous composite on bioresorbability and mechanical strength was investigated.
The fibril formation, in mixing a self-organized HAp/Col nanocomposite and sodium phosphate buffer at a neutral condition,
occurred during incubation at 37 °C, resulting in gelation of the mixture. The porous composites with and without the incubation
were obtained by freeze-drying technique, in which macroscopic open pores were formed. The compressive strength of the porous
composite with the incubation (34.1 ± 1.6 kPa) was significantly higher than that without the incubation (28.0 ± 3.3 kPa)
due to the fibril formation of Col. The implantations of the porous composites treated with a dehydrothermal treatment in
bone holes revealed that bioresorption was clearly depended on the fibril formation. The bioresorbability in vivo was almost
matched to the in vitro test using enzymatic reaction of collagenase. 相似文献
66.
A Yamamoto E Shimizu E Takeuchi H Houchi H Doi H Bando T Ogura S Sone 《Canadian Metallurgical Quarterly》1999,56(2):129-133
To clarify the host immune response and explore a new serological marker of lung cancer, we examined serum c-Myc antigens and auto-antibodies against c-Myc in 68 lung cancer patients and 30 healthy volunteers using bacterially synthesized glutathione S-transferase c-Myc fusion proteins and immunoblotting. The detection rate of anti-c-Myc antibodies was 13.2% (9/68) in lung cancer patients and 3.3% (1/30) in healthy volunteers. These anti-c-Myc antibodies were directed toward exon 2 alone (4/68), exon 3 alone (1/68), and both exon 2 and exon 3 (4/68) of c-Myc. Circulating c-Myc antigen was not detected in any individuals with lung cancer and normal controls. Age, sex, performance status, histology, stage, smoking history, and prior treatment of the patients with and without anti-c-Myc antibodies were not significantly different. The low incidence of anti-c-Myc antibodies and c-Myc antigens in peripheral blood suggests that these examinations are not useful in the serological diagnosis of lung cancer. 相似文献
67.
Takakazu Yamamoto Mahmut Abla Takahisa Shimizu Dahrma Komarudin Bang-Lin Lee Eriko Kurokawa 《Polymer Bulletin》1999,42(3):321-327
Summary
Temperature dependent electrical conductivity of substituted polythiophenes (poly(3,4-ethylenedioxythiophene) PEDOTh and head-to-tail
type poly(3-alkylthiophene) HT-P3RTh) has been measured. The electrical conductivity (σ) of p-doped PEDOTh and HT-P3RTh obeys
equations of a type, ln σ= ln σo− (To/T)0.25, with the To value of about 105–107 K.
Received: 21 December 1998/Revised version: 8 February 1999/Accepted: 15 February 1999 相似文献
68.
69.
70.