全文获取类型
收费全文 | 53127篇 |
免费 | 8901篇 |
国内免费 | 6056篇 |
专业分类
化学 | 37242篇 |
晶体学 | 686篇 |
力学 | 3526篇 |
综合类 | 412篇 |
数学 | 6383篇 |
物理学 | 19835篇 |
出版年
2024年 | 127篇 |
2023年 | 1040篇 |
2022年 | 1486篇 |
2021年 | 1703篇 |
2020年 | 2012篇 |
2019年 | 1959篇 |
2018年 | 1691篇 |
2017年 | 1613篇 |
2016年 | 2375篇 |
2015年 | 2337篇 |
2014年 | 2926篇 |
2013年 | 3659篇 |
2012年 | 4585篇 |
2011年 | 4832篇 |
2010年 | 3289篇 |
2009年 | 3144篇 |
2008年 | 3459篇 |
2007年 | 3141篇 |
2006年 | 3046篇 |
2005年 | 2397篇 |
2004年 | 1890篇 |
2003年 | 1627篇 |
2002年 | 1552篇 |
2001年 | 1270篇 |
2000年 | 1191篇 |
1999年 | 1158篇 |
1998年 | 1000篇 |
1997年 | 927篇 |
1996年 | 967篇 |
1995年 | 829篇 |
1994年 | 733篇 |
1993年 | 585篇 |
1992年 | 584篇 |
1991年 | 493篇 |
1990年 | 426篇 |
1989年 | 354篇 |
1988年 | 279篇 |
1987年 | 239篇 |
1986年 | 224篇 |
1985年 | 208篇 |
1984年 | 157篇 |
1983年 | 113篇 |
1982年 | 91篇 |
1981年 | 66篇 |
1980年 | 45篇 |
1979年 | 28篇 |
1978年 | 24篇 |
1977年 | 27篇 |
1976年 | 23篇 |
1973年 | 26篇 |
排序方式: 共有10000条查询结果,搜索用时 464 毫秒
11.
Yi-Tong Xu Tian-Yang Zhang Zheng Li Xiang-Nan Liu Yuan-Cheng Zhu Wei-Wei Zhao Hong-Yuan Chen Jing-Juan Xu 《Electroanalysis》2022,34(6):947-955
Photoelectrochemical (PEC) cytosensors, a combination of the PEC process and the living-cell assay, have emerged as a powerful tool in the analytical and biological science. This mini review provides a brief introduction of this arena and summaries the key steps about the development of PEC cytosensors with representative examples, followed by future prospects based on our own opinions. 相似文献
12.
Li Quanxin Li Zheng He Cheng Sun Huilin Tan Shengheng Zhang Hua 《Journal of Radioanalytical and Nuclear Chemistry》2022,331(5):2105-2115
Journal of Radioanalytical and Nuclear Chemistry - The simplified 8-oxide system (SiO2-B2O3-Na2O-Al2O3-CaO-TiO2-MoO3-La2O3) has been prepared under two types of cooling methods, and analyzed with... 相似文献
13.
Xu Mengtao Li Changyou Sun Yang Yang Tianzhi Zhang Hongzhuang Liu Zhendong Liu Haiyang Li Zhenyuan Zhang Yimin 《Nonlinear dynamics》2021,105(4):3061-3092
Nonlinear Dynamics - Investigation of the dynamic characteristics of linear guideway is essential for enhancing structural performance of machine tools. However, few mechanical models are... 相似文献
14.
Interactions of the vector breathers for the coupled Hirota system with $$4\times 4$$ 4 × 4 Lax pair
Nonlinear Dynamics - In this paper, we investigate the interactions of the vector breathers for the coupled Hirota system with $$4\times 4$$ Lax pair. Firstly, we give the first-order breather... 相似文献
15.
Kai Cheng Xiao-Shuai Zhang Jie An Cheng Li Ruo-Yun Zhang Run Ye Prof. Dr. Bang-Jiao Ye Prof. Dr. Bo Liu Prof. Dr. Yuan-Di Zhao 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(31):7553-7560
Given their superior penetration depths, photosensitizers with longer absorption wavelengths present broader application prospects in photodynamic therapy (PDT). Herein, Ag2S quantum dots were discovered, for the first time, to be capable of killing tumor cells through the photodynamic route by near-infrared light irradiation, which means relatively less excitation of the probe compared with traditional photosensitizers absorbing short wavelengths. On modification with polydopamine (PDA), PDA-Ag2S was obtained, which showed outstanding capacity for inducing reactive oxygen species (increased by 1.69 times). With the addition of PDA, Ag2S had more opportunities to react with surrounding O2, which was demonstrated by typical triplet electron spin resonance (ESR) analysis. Furthermore, the PDT effects of Ag2S and PDA-Ag2S achieved at longer wavelengths were almost identical to the effects produced at 660 nm, which was proved by studies in vitro. PDA-Ag2S showed distinctly better therapeutic effects than Ag2S in experiments in vivo, which further validated the enhanced regulatory effect of PDA. Altogether, a new photosensitizer with longer absorption wavelength was developed by using the hitherto-unexplored photodynamic function of Ag2S quantum dots, which extended and enhanced the regulatory effect originating from PDA. 相似文献
16.
Dr. Yong-Sheng Wei Dr. Liming Sun Miao Wang Dr. Jinhua Hong Dr. Lianli Zou Hongwen Liu Dr. Yu Wang Dr. Mei Zhang Dr. Zheng Liu Prof. Yinwei Li Prof. Satoshi Horike Prof. Kazu Suenaga Prof. Qiang Xu 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(37):16147-16156
Understanding the thermal aggregation behavior of metal atoms is important for the synthesis of supported metal clusters. Here, derived from a metal–organic framework encapsulating a trinuclear FeIII2FeII complex (denoted as Fe3) within the channels, a well-defined nitrogen-doped carbon layer is fabricated as an ideal support for stabilizing the generated iron nanoclusters. Atomic replacement of FeII by other metal(II) ions (e.g., ZnII/CoII) via synthesizing isostructural trinuclear-complex precursors (Fe2Zn/Fe2Co), namely the “heteroatom modulator approach”, is inhibiting the aggregation of Fe atoms toward nanoclusters with formation of a stable iron dimer in an optimal metal–nitrogen moiety, clearly identified by direct transmission electron microscopy and X-ray absorption fine structure analysis. The supported iron dimer, serving as cooperative metal–metal site, acts as efficient oxygen evolution catalyst. Our findings offer an atomic insight to guide the future design of ultrasmall metal clusters bearing outstanding catalytic capabilities. 相似文献
17.
Ruirui Xu Kun Wang Haoying Liu Prof. Dr. Weijun Tang Dr. Huaming Sun Prof. Dr. Dong Xue Prof. Dr. Jianliang Xiao Prof. Dr. Chao Wang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(49):22143-22148
A ruthenium-catalyzed formal anti-Markovnikov hydroamination of allylic alcohols for the synthesis of chiral γ-amino alcohols is presented. Proceeding via an asymmetric hydrogen-borrowing process, the catalysis allows racemic secondary allylic alcohols to react with various amines, affording enantiomerically enriched chiral γ-amino alcohols with broad substrate scope and excellent enantioselectivities (68 examples, up to >99 % ee). 相似文献
18.
19.
Nonlinear Dynamics - With an increasing number of people sharing feelings and opinions online, the online platforms have become one of the most important channels for public opinion dissemination.... 相似文献
20.