全文获取类型
收费全文 | 1061篇 |
免费 | 59篇 |
国内免费 | 2篇 |
专业分类
电工技术 | 38篇 |
综合类 | 2篇 |
化学工业 | 350篇 |
金属工艺 | 23篇 |
机械仪表 | 31篇 |
建筑科学 | 19篇 |
矿业工程 | 1篇 |
能源动力 | 43篇 |
轻工业 | 62篇 |
石油天然气 | 2篇 |
无线电 | 55篇 |
一般工业技术 | 276篇 |
冶金工业 | 66篇 |
原子能技术 | 24篇 |
自动化技术 | 130篇 |
出版年
2024年 | 3篇 |
2023年 | 22篇 |
2022年 | 21篇 |
2021年 | 59篇 |
2020年 | 26篇 |
2019年 | 37篇 |
2018年 | 31篇 |
2017年 | 44篇 |
2016年 | 46篇 |
2015年 | 33篇 |
2014年 | 53篇 |
2013年 | 83篇 |
2012年 | 69篇 |
2011年 | 79篇 |
2010年 | 79篇 |
2009年 | 73篇 |
2008年 | 55篇 |
2007年 | 41篇 |
2006年 | 46篇 |
2005年 | 29篇 |
2004年 | 16篇 |
2003年 | 14篇 |
2002年 | 13篇 |
2001年 | 9篇 |
2000年 | 9篇 |
1999年 | 8篇 |
1998年 | 20篇 |
1997年 | 14篇 |
1996年 | 15篇 |
1995年 | 12篇 |
1994年 | 6篇 |
1993年 | 6篇 |
1992年 | 2篇 |
1991年 | 4篇 |
1990年 | 2篇 |
1989年 | 3篇 |
1988年 | 4篇 |
1986年 | 3篇 |
1985年 | 7篇 |
1984年 | 3篇 |
1983年 | 6篇 |
1982年 | 5篇 |
1981年 | 5篇 |
1980年 | 3篇 |
1979年 | 1篇 |
1977年 | 1篇 |
1976年 | 2篇 |
排序方式: 共有1122条查询结果,搜索用时 15 毫秒
91.
Shinichi Kitade Kazuo Asuka Isamu Akiba Yusuke Sanada Kazuo Sakurai Hiroyasu Masunaga 《Polymer》2013,54(1):246-257
Shear-induced crystallization of a long chain hyper-branched polypropylene (LCB-PP, denoted PP-3) was carried out at a relatively high temperature of 170 °C, close to its melting temperature of 158 °C. Small-angle X-ray scattering (SAXS) showed that the intensity ratio of the normal to the perpendicular to the shear (V/H) was always larger than 1 for PP-3, indicating that shish-like structures were predominately formed and further growth to kebab was suppressed in PP-3. The crystallization behavior of PP-3 can be explained by the nature of PP-3 that there were a large amount of crystallization nuclei due to their branching points, and the point-like precursors formed from these nuclei were arrayed linearly along the shear direction and transformed into thread-like precursors or premature shishs; however, owing to the large amount of branching, further progress in crystallization was suppressed. 相似文献
92.
The feasibility of a direct internal reforming (DIR) solid oxide fuel cell (SOFC) running on wet palm‐biodiesel fuel (BDF) was demonstrated. Simultaneous production of H2‐rich syngas and electricity from BDF could be achieved. A power density of 0.32 W cm?2 was obtained at 0.4 A cm?2 and 800 °C under steam to carbon ratio of 3.5. Subsequent durability testing revealed that a DIR‐SOFC running on wet palm‐BDF exhibited a stable voltage of around 0.8 V at 0.2 A cm?2 for more than 1 month with a degradation rate of approximately 15 % / 1000 h. The main cause of the degradation was an increase in the ohmic resistance. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
93.
Shiro Asano Toshihisa Okuyama Toshiwo Oonawa Yutaka Yanagi Mitsuru Ejiri Toshio Kanahara Koji Ichihashi Atsushi Kikuchi Shoichi Mizumaki Kei Masaki Yusuke K. Shibama Masahiro Katayama Akira Sakasai 《Fusion Engineering and Design》2011,86(9-11):1816-1820
The real vacuum vessel (VV) manufacturing of JT-60SA has started since November 2009 at Toshiba. Prior to starting manufacturing, fundamental welding R&Ds had been performed by three stages. In the first stage, primary tests for screening welding method were performed. In the second stage, the trial welding for 1 m-long straight and curved double shell samples were conducted. The dependences of welding quality and distortion on the welding conditions, such as arc voltage and current, setting accuracy, welding sequence, and the shape of grooves were studied. In addition, welding condition with low heat input was explored. In the last stage, fabrication sequence was confirmed and established by the trial manufacturing of the 20° upper half mock-up [1]. This paper presents the R&D results obtained in the first and second stages. 相似文献
94.
Color and intensity coding provide perceptual cues to segregate categories of objects within a visual display, allowing operators to search more efficiently for needed information. Even within a perceptually distinct subset of display elements, however, it may often be useful to prioritize items representing urgent or task-critical information. The design of symbology to produce search asymmetries (Treisman & Souther, 1985) offers a potential technique for doing this, but it is not obvious from existing models of search that an asymmetry observed in the absence of extraneous visual stimuli will persist within a complex color- or intensity-coded display. To address this issue, in the current study we measured the strength of a visual search asymmetry within displays containing color- or intensity-coded extraneous items. The asymmetry persisted strongly in the presence of extraneous items that were drawn in a different color (Experiment 1) or a lower contrast (Experiment 2) than the search-relevant items, with the targets favored by the search asymmetry producing highly efficient search. The asymmetry was attenuated but not eliminated when extraneous items were drawn in a higher contrast than search-relevant items (Experiment 3). Results imply that the coding of symbology to exploit visual search asymmetries can facilitate visual search for high-priority items even within color- or intensity-coded displays. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
95.
Bruce A. Julian Hitoshi Suzuki Goce Spasovski Yusuke Suzuki Yasuhiko Tomino Jan Novak 《Proteomics. Clinical applications》2009,3(9):1023-1028
Chronic kidney disease accounts for a significant portion of many national health-care budgets. In this viewpoint, we highlight recent advances in urinary proteomic analyses that potentially may soon enhance the care of afflicted patients. To achieve this goal, cooperation of interdisciplinary teams from around the world will be vital, so as to standardize methodology for preparation urine samples and technical aspects of the analyses, and for better application of results. These collaborative activities will facilitate translational research in kidney diseases. 相似文献
96.
We investigated the temperature dependence, at low temperaturs, of sound velocity in sintered silicon carbide samples, containing three different sintering additives, boron or beryllium oxide or aluminum nitride. It was found that samples containing AlN or B showed lnT dependence (T is the temperature) of sound velocity but the one with BeO did not. The slope of the lnT dependence, which is proportional to the density of states of two level tunneling systems (TLS), is much larger for SiC with AlN than that with B. This sequence and no lnT dependence in BeO, correlate with the solubility of these additives into SiC, suggesting that the TLS, at least in this case, are created by the additives in solid solutions in the crystals. The samples containing B were heat treated to allow grain growth as well as densification. The density of states of TLS in these samples (measured by the slope of the lnT dependence of velocity) increased as the grain size increased. This suggests that the TLS do not reside in grain boundaries and that B migrates from the grain boundaries (where it originally segregated) into the bulk, thus creating more TLS inside the grains. 相似文献
97.
Takuro Kikuchi Yusuke Fukushima Kouichi Nishimura 《Canadian Metallurgical Quarterly》2005,19(4):117-129
The boundary condition for concentration of snow particles at the bed is necessary to calculate snowdrifts by a numerical analysis model. The flux type or the gradient type boundary conditions are reasonable. An idea of an entrainment coefficient of snow particle at the snow surface is useful. The values of the coefficient are considered to be a function of the density and viscosity of the working fluid and the properties of snow particles. In this paper, the values of the coefficient are estimated based on the k–ε turbulence model and the distribution of snow particle flux observed at the Mizuho Station, Antarctica in 2000, assuming the steady, fully developed flow over a flat snow surface. The snow entrainment coefficient is two or three orders smaller than the sand entrainment coefficient in a river. The reason is that the specific weight of snow particles in air is much larger than that of sand particles in water. 相似文献
98.
Telechelically bis(hydrodimethylsilyl)-functionalized oligo(dimethylsiloxane)s or aromatics were found to give polymers constituting
of alternating disilylene and oligodimethylsiloxane or 4,4′-diylaromatics as repeating units by dehydrogenative coupling reaction
in the presence of palladium dibenzylideneacetone complex. The same catalyst gave polysilylenes with trisiloxane pendant from
1,1-dihydro-1,3,3,5,5,7,7,7-octamethyltetrasiloxane.
Received: 18 October 1996/Accepted: 31 October 1996 相似文献
99.
Yusuke Suzuki Chisato Takenaka Rie Tomioka Hiromi Tsubota Yuka Takasaki Tomonari Umemura 《Mine Water and the Environment》2016,35(3):265-272
Bryophytes with high As accumulation affinity were identified in the aquatic environment. We surveyed a stream near copper mine tailings and then conducted laboratory experiments to confirm As accumulation in the bryophytes with high As affinity. We found that a moss, Scopelophila cataractae, accumulates As in addition to Cu in aquatic environments and confirmed it in laboratory experiments. The highest value for As in S. cataractae from the field survey was 1300 mg/kg dry weight at relatively low As concentrations in the stream water (0.005 mg/L). In addition, Brachythecium plumosum and Rhynchostegium riparioides may also be useful bryophytes for accumulation of Cu and As, though the mechanisms of As accumulation might differ between these two bryophytes and S. cataractae. 相似文献
100.
A 4‐Fold‐Symmetry Hexagonal Ruthenium for Magnetic Heterostructures Exhibiting Enhanced Perpendicular Magnetic Anisotropy and Tunnel Magnetoresistance 下载免费PDF全文