全文获取类型
收费全文 | 1418篇 |
免费 | 45篇 |
国内免费 | 6篇 |
专业分类
化学 | 1152篇 |
晶体学 | 6篇 |
力学 | 18篇 |
数学 | 63篇 |
物理学 | 230篇 |
出版年
2023年 | 15篇 |
2022年 | 6篇 |
2021年 | 8篇 |
2020年 | 34篇 |
2019年 | 19篇 |
2018年 | 8篇 |
2016年 | 19篇 |
2015年 | 21篇 |
2014年 | 19篇 |
2013年 | 67篇 |
2012年 | 74篇 |
2011年 | 95篇 |
2010年 | 44篇 |
2009年 | 48篇 |
2008年 | 90篇 |
2007年 | 57篇 |
2006年 | 93篇 |
2005年 | 80篇 |
2004年 | 92篇 |
2003年 | 72篇 |
2002年 | 76篇 |
2001年 | 25篇 |
2000年 | 14篇 |
1999年 | 26篇 |
1998年 | 22篇 |
1997年 | 13篇 |
1996年 | 18篇 |
1995年 | 10篇 |
1994年 | 11篇 |
1993年 | 9篇 |
1992年 | 15篇 |
1991年 | 13篇 |
1990年 | 14篇 |
1989年 | 12篇 |
1988年 | 5篇 |
1987年 | 6篇 |
1986年 | 8篇 |
1985年 | 22篇 |
1984年 | 23篇 |
1983年 | 11篇 |
1982年 | 19篇 |
1981年 | 14篇 |
1980年 | 7篇 |
1979年 | 24篇 |
1978年 | 9篇 |
1977年 | 10篇 |
1976年 | 10篇 |
1975年 | 13篇 |
1974年 | 16篇 |
1973年 | 7篇 |
排序方式: 共有1469条查询结果,搜索用时 46 毫秒
71.
Susumu Takigawa Masanori Koshimizu Takio Noguchi Tsutomu Aida Seiichi Takami Tadafumi Adschiri Yutaka Fujimoto Akira Yoko Gimyeong Seong Takaaki Tomai Keisuke Asai 《Journal of Radioanalytical and Nuclear Chemistry》2017,314(2):611-615
We synthesized liquid scintillators incorporating ZrO2 nanoparticles for application in neutrinoless double beta decay experiments. ZrO2 nanoparticles of less than 10 nm in size were synthesized with sub- and supercritical hydrothermal methods. The Zr concentrations in the liquid scintillators were determined to be up to 1.4 wt% with inductively coupled plasma analysis, and the liquid scintillators were transparent to scintillation. These results indicate that these methods are applicable for the preparation of liquid scintillators for neutrinoless double beta decay experiments. 相似文献
72.
Seiichi Ohta Susumu Inasawa Yukio Yamaguchi 《Journal of Polymer Science.Polymer Physics》2012,50(12):863-869
When a mixture of liquid crystal (LC) and photo reactive monomer is irradiated by UV light, polymerization occurs and LC droplets form through phase separation, producing polymer dispersed LCs (PDLCs). Although size control of LC droplets and reduced amounts of LC in PDLC films are important in applications, precise size control of LC droplets at a low LC fraction has not yet been accomplished. In this study, the phase diagrams of the LC/initial monomer and the LC/polymer during polymerization were used to control LC droplet size at various LC fractions. Both the relative position of the sample in the initial phase diagram and the shift of the phase separation line during polymerization were shown to be important in determining the size of LC droplets. Our results are expected to provide a new strategy for precise size control of LC droplets especially at a low LC fraction range, which would be a great help for PDLC applications. © 2012 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2012 相似文献
73.
74.
75.
76.
77.
Takaaki Taguchi Masaki Yabe Hitomi Odaki Miki Shinozaki Mikko Metsä-Ketelä Takao Arai Susumu Okamoto Koji Ichinose 《Chemistry & biology》2013,20(4):510-520
Highlights? ActVA-ORF5 is a flavin-dependent monooxygenase required for actinorhodin biosynthesis ? ActVA-ORF5 and its three close homologs were functionally dissected ? ActVA-ORF5 and Gra-21 are bifunctional at C-6/C-8, while Med-7 acts only for C-6 ? AlnT exhibits different regiospecificity for oxidation of tricyclic substrates 相似文献
78.
Tetsuya Tsuda Susumu Kuwabata Gery R. Stafford Charles L. Hussey 《Journal of Solid State Electrochemistry》2013,17(2):409-417
The electrochemistry of Hf(IV) and the electrodeposition of Al–Hf alloys were examined in the Lewis acidic 66.7–33.3 mol% aluminum chloride-1-ethyl-3-methylimidazolium chloride molten salt containing HfCl4. When cyclic staircase voltammetry was carried out at a platinum disk electrode in this melt, the deposition and stripping waves for Al shifted to negative and positive potentials, respectively, suggesting that aluminum stripping is more difficult due to the formation of Al–Hf alloys. Al–Hf alloy electrodeposits containing ~13 at.% Hf were obtained on Cu rotating wire and cylinder electrodes. The Hf content in the Al–Hf alloy deposits depended on the HfCl4 concentration in the melt, the electrodeposition temperature, and the applied current density. The deposits were composed of dense crystals and were completely chloride-free. The chloride-induced pitting corrosion potential of the resulting Al–Hf alloys was approximately +0.30 V against pure aluminum when the Hf content was above 10 at.%. 相似文献
79.
Susumu Ohira 《合成通讯》2013,43(3-4):561-564
Dimethyl (1-diazo-2-oxopropyl) phosphonate (3) was transformed to dimethyl (diazomethyl)—phosphonate (4), which was used for the synthesis of enol ether or alkyne without isolation. 相似文献
80.
Tetsuyuki Taniai Sachiko Wakasugi Susumu Hashimoto Ai Shimada Tatsuya Urabe Kazuya Takahashi 《International journal of environmental analytical chemistry》2013,93(5):601-612
To obtain information on the environmental impact of materials eluted from volcanic ashes of Mt. Oyama, Miyake Island, which erupted in July 2000, the dissolution behaviours of heavy metals and rare-earth elements from the volcanic ashes were examined. The most important characteristic of the Mt. Oyama eruption is that sulphur dioxide (SO2) gas has been continuously released, and all persons living on Miyake Island have been required to evacuate. To estimate in terms of the volcanic eruption using SO2 gas, the ash nature in Mt. Usu, Hokkaido, was also examined and compared with that in Mt. Oyama. When rain water mixed the ashes, the water from the ashes of Mt. Oyama became acidic because of the sulphuric acid. Therefore, SO2 gas in Mt. Oyama can accelerate the dissolution of protons and heavy metals in the ashes, whereas the rain water in Mt. Usu was not acidic and the dissolution of the heavy metals was not so evident compared with that in the case of Mt. Oyama. With this sulphuric acid, heavy metals such as As, Cd, Pb and Hg in the ashes in Mt. Oyama easily dissolved owing to the low pH. The ashes in Mt. Oyama had been released for eight years and the amount of fallen ashes was estimated to be 33 billion tons. The weights of the harmful heavy metals in the volcanic ashes, such as As, Cd, Pb and Hg, were estimated to be 3.8?×?102, 1.3?×?103, 1.1?×?103 and 29?kg, respectively, and these heavy metals were dissolved and diluted in seawater. Therefore, the concentration and species (chemical form) of these metals should be carefully monitored in the future. Moreover, SO2 gas, which has a direct effect on human health and has been monitored continuously, causes other effects, such as facilitation of metal ion elution and rock aeration. 相似文献