全文获取类型
收费全文 | 14167篇 |
免费 | 2400篇 |
国内免费 | 2838篇 |
专业分类
化学 | 12078篇 |
晶体学 | 211篇 |
力学 | 756篇 |
综合类 | 191篇 |
数学 | 1714篇 |
物理学 | 4455篇 |
出版年
2024年 | 7篇 |
2023年 | 164篇 |
2022年 | 292篇 |
2021年 | 383篇 |
2020年 | 437篇 |
2019年 | 579篇 |
2018年 | 436篇 |
2017年 | 482篇 |
2016年 | 643篇 |
2015年 | 764篇 |
2014年 | 849篇 |
2013年 | 1126篇 |
2012年 | 1304篇 |
2011年 | 1354篇 |
2010年 | 1020篇 |
2009年 | 1014篇 |
2008年 | 1152篇 |
2007年 | 990篇 |
2006年 | 879篇 |
2005年 | 849篇 |
2004年 | 696篇 |
2003年 | 544篇 |
2002年 | 663篇 |
2001年 | 565篇 |
2000年 | 419篇 |
1999年 | 309篇 |
1998年 | 260篇 |
1997年 | 199篇 |
1996年 | 140篇 |
1995年 | 129篇 |
1994年 | 139篇 |
1993年 | 100篇 |
1992年 | 101篇 |
1991年 | 96篇 |
1990年 | 75篇 |
1989年 | 46篇 |
1988年 | 51篇 |
1987年 | 27篇 |
1986年 | 27篇 |
1985年 | 26篇 |
1984年 | 13篇 |
1983年 | 16篇 |
1982年 | 9篇 |
1981年 | 7篇 |
1980年 | 4篇 |
1977年 | 3篇 |
1943年 | 1篇 |
1939年 | 1篇 |
1936年 | 7篇 |
1935年 | 1篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
Hua Saixiang Zhu Huichao Wang Xiao Wu Mingyuan Wu Qingyun Liu Jiuyi Yang Jianjun Zhang Jianan 《Cellulose (London, England)》2022,29(13):7465-7475
Cellulose - Ultraviolet (UV) protective cotton fabric is a convenient and reliable way to protect human body from sunlight. Herein, a polymerizable UV-absorber,... 相似文献
2.
Journal of Optimization Theory and Applications - We distinguish two kinds of piecewise linear functions and provide an interesting representation for a piecewise linear function between two normed... 相似文献
3.
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
4.
In this article,we study the initial boundary value problem of coupled semi-linear degenerate parabolic equations with a singular potential term on manifolds with corner singularities.Firstly,we introduce the corner type weighted p-Sobolev spaces and the weighted corner type Sobolev inequality,the Poincare′inequality,and the Hardy inequality.Then,by using the potential well method and the inequality mentioned above,we obtain an existence theorem of global solutions with exponential decay and show the blow-up in finite time of solutions for both cases with low initial energy and critical initial energy.Significantly,the relation between the above two phenomena is derived as a sharp condition.Moreover,we show that the global existence also holds for the case of a potential well family. 相似文献
5.
Zhang Tinggui Xi Ya Fei Shao-Ming 《International Journal of Theoretical Physics》2021,60(8):2909-2915
We study the Bell nonlocality of high dimensional quantum systems based on quantum entanglement. A quantitative relationship between the maximal expectation value B of Bell operators and the quantum entanglement concurrence C is obtained for even dimension pure states, with the upper and lower bounds of B governed by C.
相似文献6.
Zhen Xi 《中国科学:化学(英文版)》2015,(3):434-435
Redox-based post-translational modification of protein thiols has become an attractive strategy in cellular homeostasis and cell signaling.Due to the reductive end of the redox buffer network,the vicinal dithiol-containing proteins(VDPs)maintains an appropriate oxidation-reduction state of proteins through the reversible transformation from vicinal dithiols to disulfide,which is responsible for a variety of 相似文献
7.
8.
9.
Over the past two decades, advanced materials with hollow interiors have received significant attention in materials research owing to their great application potential across a vast number of technological fields. Though with great difficulty, multi-shelled hollow metal–organic frameworks (MSHMs) have also been successfully synthesized in recent years. Herein, a rational shell-by-shell soft-templating protocol has been devised to fabricate highly uniform multi-shelled hollow cobalt-imidazole-based MOF (ZIF-67). For the first time, it has become possible to endow mesoporosity to this new type of functional material (i.e., mesoporous MOFs). When used as carrier materials in catalytic reactions, in principle, these mesoporous MSHMs with high surface area not only improve the dispersity of metal nanoparticles (NPs), but also efficiently facilitate the mass diffusion of the reactions, resulting in enhanced catalyst activity. Moreover, the obtained MSHMs/M nanocomposites serve as base-metal bifunctional catalysts for one-pot oxidation-Knoevenagel condensation cascade reaction, in which the MSHMs itself serves as a pristine active catalyst in addition to its role of catalyst support. The results demonstrate that excellent multifunctional catalysts can be achieved via preparing intrinsically microporous bulk MOFs into extrinsically mesoporous MSHMs which possess many structural merits that conventional bulk MOFs do not have. 相似文献
10.
Jia Yang Xingang Li Wenjun Li Xin Xi Qian Du Feng Pan Songqing Liu 《Biomedical chromatography : BMC》2020,34(8):e4857
Because of its unpredictable side effects and efficacy, the anticancer drug docetaxel (DTX) requires improved characterisation of its pharmacokinetic profiles through population pharmacokinetic studies. A sensitive and rugged LC–MS/MS method for the detection of DTX in human plasma was developed and optimised using paclitaxel as an internal standard (IS). The plasma samples underwent rapid extraction using hybrid solid-phase extraction-protein precipitation. The analyte and IS were separated with an isocratic system on a Zorbax Eclipse Plus C18 column using water containing 0.05% acetic acid along with 20 μM of sodium acetate and methanol (30/70, v/v) as the mobile phase. Quantification was performed using a triple quadrupole mass spectrometer through multiple reaction monitoring in positive mode, using the m/z 830.3 → 548.8 and m/z 876.3 → 307.7 transitions for DTX and paclitaxel, respectively. The range of the calibration curve was 1–500 ng/mL for DTX, and the linear correlation coefficient was >0.99. The accuracies ranged from −4.6 to 4.2%, and the precision was no higher than 7.0% for the analytes. No significant matrix effect was observed. Both DTX and the IS showed considerable recovery. This method was finally applied to the establishment of a population pharmacokinetic model to optimise the clinical use of DTX. 相似文献