全文获取类型
收费全文 | 1362篇 |
免费 | 228篇 |
国内免费 | 151篇 |
专业分类
化学 | 911篇 |
晶体学 | 27篇 |
力学 | 339篇 |
综合类 | 7篇 |
数学 | 127篇 |
物理学 | 330篇 |
出版年
2024年 | 3篇 |
2023年 | 17篇 |
2022年 | 48篇 |
2021年 | 54篇 |
2020年 | 76篇 |
2019年 | 58篇 |
2018年 | 41篇 |
2017年 | 70篇 |
2016年 | 114篇 |
2015年 | 84篇 |
2014年 | 78篇 |
2013年 | 109篇 |
2012年 | 89篇 |
2011年 | 110篇 |
2010年 | 74篇 |
2009年 | 77篇 |
2008年 | 74篇 |
2007年 | 61篇 |
2006年 | 69篇 |
2005年 | 37篇 |
2004年 | 41篇 |
2003年 | 56篇 |
2002年 | 40篇 |
2001年 | 34篇 |
2000年 | 24篇 |
1999年 | 42篇 |
1998年 | 29篇 |
1997年 | 16篇 |
1996年 | 13篇 |
1995年 | 17篇 |
1994年 | 9篇 |
1993年 | 14篇 |
1992年 | 9篇 |
1991年 | 6篇 |
1990年 | 4篇 |
1989年 | 8篇 |
1988年 | 8篇 |
1987年 | 2篇 |
1986年 | 4篇 |
1985年 | 8篇 |
1984年 | 4篇 |
1983年 | 1篇 |
1981年 | 2篇 |
1978年 | 1篇 |
1971年 | 1篇 |
1957年 | 4篇 |
1936年 | 1篇 |
排序方式: 共有1741条查询结果,搜索用时 15 毫秒
31.
(C6H5)3MX2 (M = As, Sb; X = OCOCF3 and M = Sb, Bi; X = SO3F, SO3CF3) compounds prepared by the interaction of triphenylmetal(V) substrates with (CF3CO)2O, (CF3SO2)2O and (FSO2)2O have been characterized by molecular weight determination, elemental and spectroscopic (IR, 1H and 19F NMR, mass) analyses. 相似文献
32.
We present a computational protocol which uses the known three-dimensional structure of a target enzyme to identify possible ligands from databases of compounds with low molecular weight. This is accomplished by first mapping the essential interactions in the binding site with the program GRID. The resulting regions of favorable interaction between target and ligand are translated into a database query, and with UNITY a flexible 3D database search is performed. The feasibility of this approach is calibrated with thrombin as the target. Our results show that the resulting hit lists are enriched with thrombin inhibitors compared to the total database. 相似文献
33.
34.
The template function of cationic particle monolayers bearing quaternary ammonium groups on their surfaces towards anionic colloids was investigated in this paper. Monodispersed cationic polymer particles having quaternary ammonium groups were self-organized on octadecylated glass plates through hydrophobic interaction. The morphology of the resulting particle monolayers was changed by tuning hydrophilic–hydrophobic balance of particles to fabricate aggregated type and dispersed type of particle monolayers. Gold and silver colloids were selectively deposited onto the particle monolayers through electrostatic interaction. The deposited gold and silver colloids on particle monolayers showed plasmon absorbance. Fluorescent silica colloids were also selectively deposited on particle monolayers to permit fluorescence labeling of the particle monolayers. Cationic particle monolayers fabricated on hydrophobic solid octadecylated were found to effectively work as templates for the deposition of above mentioned inorganic colloids. 相似文献
35.
《Mendeleev Communications》2021,31(5):726-727
Low-temperature XRD measurements were performed to confirm the phase composition and structural parameters of the electrochemically deposited Cu2ZnSnSe4 thin films on flexible metal substrates. 相似文献
36.
《Electroanalysis》2018,30(2):345-352
We reported here three simple, low cost and easy to accomplish strategies for the fabrication of microelectrodes and other conductive patterns using ordinary office laser‐printers. In this work, toner patterns were directly printed onto the flexible substrate, acting as a mask to create the intended conductive design. To highlight the versatility of such technology, toner‐printed patterns were employed in two diverse ways: one in which the patterned toner had the exact design of the electrode and other employing a reverse toner‐printed pattern. The first one was used for the adaptation of the well‐known printed circuit board (PCB) fabrication technique, but using direct toner printing (DTP) in an already conductive flexible substrate. The second was employed for the two remaining strategies: one based on the deposition of conductive film, followed by lift‐off process; and another based on drop‐casting of a conductive ink into the formed toner cavities, followed by thermal cure. As proof‐of‐concept, all three DTP strategies were used for the fabrication of miniaturized gold electrodes in polyimide substrate, and electrochemical performance of each obtained electrode was evaluated by cyclic voltammetry. Insights about DTP technology, alignment issues, advantages, limitations and resolution of each presented approach were provided. Finally, direct toner printing showed to be a simple, affordable and quite promising technology for the fabrication of low cost point‐of‐care electrochemical devices using flexible platforms. 相似文献
37.
Shuhei Akahori Prof. Dr. Takahiro Sasamori Prof. Dr. Hiroshi Shinokubo Prof. Dr. Yoshihiro Miyake 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(31):8178-8184
Quadruply BN-fused tetrathia[8]circulenes were synthesized through four-fold electrophilic borylation. The single-crystal X-ray diffraction analysis revealed that the BN-fused tetrathia[8]circulene with peripheral phenyl groups exhibits crystal polymorphism, in which the circulene core adopts both planar and saddle conformations in the solid state. The experimental and theoretical studies revealed that the weaker aromaticity of azaborine compared with benzene renders the flexibility of the BN-fused tetrathia[8]circulenes. 相似文献
38.
Room temperature and low temperature (120 °C) laser-assisted glass frit bonding of soda-lime glass substrates are accomplished in this work. The locally laser melted bonding showed hermeticity with helium leak rate of <5×10−8 atm cm3 s−1, maintaining its leak rate even after standard climatic cycle tests. Small size devices were bonded at room temperature while larger areas were sealed at the process temperature of 120 °C. The sealing parameters were optimized through response surface methodology that makes the process capable for further development regardless of device size. 相似文献
39.
40.
Kaisei Matsumoto Kazuki Ueno Prof. Dr. Jun Hirotani Prof. Dr. Yutaka Ohno Prof. Dr. Haruka Omachi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(28):6118-6121
Owing to their remarkable properties, single-walled carbon nanotube thin-film transistors (SWCNT-TFTs) are expected to be used in various flexible electronics applications. To fabricate SWCNT channel layers for TFTs, solution-based film formation on a self-assembled monolayer (SAM) covered with amino groups is commonly used. However, this method uses highly oxidized surfaces, which is not suitable for flexible polymeric substrates. In this work, a solution-based SWCNT film fabrication using methoxycarbonyl polyallylamine (Moc-PAA) is reported. The NH2-terminated surface of the cross-linked Moc-PAA layer enables the formation of highly dense and uniform SWCNT networks on both rigid and flexible substrates. TFTs that use the fabricated SWCNT thin film exhibited excellent performance with small variations. The presented simple method to access SWCNT thin film accelerates the realization of flexible nanoelectronics. 相似文献