全文获取类型
收费全文 | 3193篇 |
免费 | 218篇 |
国内免费 | 248篇 |
专业分类
化学 | 2528篇 |
晶体学 | 113篇 |
力学 | 93篇 |
综合类 | 1篇 |
数学 | 39篇 |
物理学 | 885篇 |
出版年
2023年 | 138篇 |
2022年 | 63篇 |
2021年 | 82篇 |
2020年 | 136篇 |
2019年 | 41篇 |
2018年 | 56篇 |
2017年 | 57篇 |
2016年 | 92篇 |
2015年 | 89篇 |
2014年 | 141篇 |
2013年 | 133篇 |
2012年 | 213篇 |
2011年 | 180篇 |
2010年 | 136篇 |
2009年 | 166篇 |
2008年 | 169篇 |
2007年 | 168篇 |
2006年 | 245篇 |
2005年 | 201篇 |
2004年 | 167篇 |
2003年 | 128篇 |
2002年 | 102篇 |
2001年 | 93篇 |
2000年 | 95篇 |
1999年 | 73篇 |
1998年 | 53篇 |
1997年 | 34篇 |
1996年 | 38篇 |
1995年 | 24篇 |
1994年 | 26篇 |
1993年 | 23篇 |
1992年 | 21篇 |
1991年 | 15篇 |
1990年 | 7篇 |
1989年 | 8篇 |
1985年 | 11篇 |
1984年 | 13篇 |
1983年 | 7篇 |
1982年 | 16篇 |
1981年 | 19篇 |
1980年 | 23篇 |
1979年 | 17篇 |
1978年 | 21篇 |
1977年 | 27篇 |
1976年 | 16篇 |
1975年 | 12篇 |
1974年 | 20篇 |
1973年 | 18篇 |
1972年 | 10篇 |
1971年 | 4篇 |
排序方式: 共有3659条查询结果,搜索用时 15 毫秒
11.
12.
Shang‐Xiong Huang‐Fu Jin‐Ni Shen Prof. Hua Lin Prof. Ling Chen Prof. Li‐Ming Wu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(27):9809-9815
A novel type of supertetrahedral connectivity is exhibited by the 72‐atom discrete supercubooctahedron in (Cs6Cl)2Cs5[Ga15Ge9Se48] ( 1 ), which undergoes both cation and anion exchange, as revealed by unambiguous single‐crystal X‐ray diffraction data. Electronic‐structure studies helped to understand the Ge/Ga distribution. 相似文献
13.
Wen‐Jing Guo Yong‐Tao Wang De‐Xian Kong Jin‐Yun Wang Prof. Qiao‐Hua Wei Guo‐Nan Chen 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(11):4205-4208
A heterometallic cluster [Ag6Au6(ethisterone)12] of an unprecedented topology was synthesized and characterized. A sensitive and specific probe for estrogen receptor α (ERα) has been developed for the first time based on the enhancement of the Ag6Au6 luminescence. 相似文献
14.
A new metal chalcogenide,γ-Hg3S2Br2(1),has been prepared by moderate-temperature solid-state reaction,and its crystal structure was determined by single-crystal X-ray diffraction analysis.Compound 1 crystallizes in space group Cmmm of orthorhombic system with a=9.1923(18),b=18.2262(5),c=4.6251(7)?,V=774.9(3)?3and Z=4.In the structure,two Hg(1),two Hg(2)and four S(1)atoms form a near square Hg4S4,and such squares are linked by Hg(3)atoms nearly linearly coordinated to two S1 atoms of two parallel Hg4S4squares to form one-dimensional infinite Hg6S4chains along c direction.Optical absorption spectra reveal the presence of sharp optical gap of 2.80 eV for 1.IR spectrum,TGA and electric resistivity have been investigated. 相似文献
15.
Regulation of Charge Delocalization in a Heteronuclear Fe2Ru System by a Stepwise Photochromic Process 下载免费PDF全文
Guang‐Tao Xu Dr. Bin Li Dr. Jin‐Yun Wang Dr. Dao‐Bin Zhang Prof. Zhong‐Ning Chen 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(8):3318-3326
Heteronuclear complexes FeCp2?DTE?C?C?Ru(dppe)2Cl ( 1 o ; dppe=1,2‐bis(diphenylphosphino)ethane, Cp=cyclopentadienyl, DTE=dithienylethene) and FeCp2?DTE?C?C?Ru(dppe)2?C?C?DTE?FeCp2 ( 2 oo ), with redox‐active ferrocenyl and ruthenium centers separated by a photochromic DTE moiety, were prepared to achieve photoswitchable charge delocalization and Fe???Ru electronic communication. Upon UV‐light irradiation of 2 oo , the Fe???Ru heterometallic electronic interaction is increasingly facilitated with stepwise photocyclization, 2 oo → 2 co → 2 cc ; this is ascribed to the gradual increase in π‐conjugated systems. The near‐infrared absorptions in mixed‐valence species [ 2 oo ]+/[ 2 co ]+/[ 2 cc ]+ are gradually intensified following the conversion of [ 2 oo ]+→[ 2 co ]+→[ 2 cc ]+, which demonstrates that the extent of charge delocalization shows progressive enhancement with stepwise photocyclization. As revealed by electrochemical, spectroscopic, and theoretical studies, complex 2 exhibits nine switchable states through stepwise photochromic and reversible redox processes. 相似文献
16.
Molecular triplets have attracted great interest across multidisciplinary fields of the research ranging from thermally activated delayed fluorescence[1],triplet-triplet annihilation(TTA)upconversion[2],to photodynamic therapy relying on TTA between triplet photosensitizers and surrounding triplet oxygen to generate singlet oxygen species[3]. 相似文献
17.
18.
Yi Liu Jiaqi Wang Shiguo Han Dr. Xitao Liu Maofan Li Zhiyun Xu Wuqian Guo Prof. Maochun Hong Prof. Junhua Luo Prof. Zhihua Sun 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(16):3494-3498
3D perovskite CsPbBr3 has recently taken a blooming position for optoelectronic applications. However, due to the lack of natural anisotropy of optical attributes, it is a great challenge to fulfil polarization-sensitive photodetection. Here, for the first time, we exploited dimensionality reduction of CsPbBr3 to tailor a 2D-multilayered hybrid perovskite, (TRA)2CsPb2Br7 ( 1 , in which TRA is (carboxy)cyclohexylmethylammonium), serving as a potential polarized-light detecting candidate. Its unique quantum-confined 2D structure results in intrinsic anisotropy of electrical conductivity, optical absorbance, and polarization-dependent responses. Particularly, it exhibits remarkable dichroism with the photocurrent ratio (Ipc/Ipa) of ≈2.1, being much higher than that of the isotropic CsPbBr3 crystal and reported CH3NH3PbI3 nanowire (≈1.3), which reveals its great potentials for polarization-sensitive photodetection. Further, crystal-based detectors of 1 show fascinating responses to the polarized light, including high detectivity (>1010 Jones), fast responding time (≈300 μs), and sizeable on/off current ratios (>104). To our best knowledge, this is the first study on 2D Cs-based hybrid perovskite exhibiting strong polarization-sensitivity. The work highlights an effective pathway to explore new polarization sensitive candidates for hybrid perovskites and promotes their future electronic applications. 相似文献
19.
20.