全文获取类型
收费全文 | 9968篇 |
免费 | 1710篇 |
国内免费 | 2000篇 |
专业分类
化学 | 7727篇 |
晶体学 | 119篇 |
力学 | 604篇 |
综合类 | 149篇 |
数学 | 1316篇 |
物理学 | 3763篇 |
出版年
2024年 | 6篇 |
2023年 | 231篇 |
2022年 | 299篇 |
2021年 | 363篇 |
2020年 | 483篇 |
2019年 | 467篇 |
2018年 | 366篇 |
2017年 | 401篇 |
2016年 | 553篇 |
2015年 | 556篇 |
2014年 | 599篇 |
2013年 | 833篇 |
2012年 | 772篇 |
2011年 | 875篇 |
2010年 | 658篇 |
2009年 | 615篇 |
2008年 | 707篇 |
2007年 | 584篇 |
2006年 | 546篇 |
2005年 | 507篇 |
2004年 | 416篇 |
2003年 | 347篇 |
2002年 | 384篇 |
2001年 | 310篇 |
2000年 | 271篇 |
1999年 | 230篇 |
1998年 | 178篇 |
1997年 | 128篇 |
1996年 | 151篇 |
1995年 | 112篇 |
1994年 | 132篇 |
1993年 | 99篇 |
1992年 | 73篇 |
1991年 | 94篇 |
1990年 | 89篇 |
1989年 | 42篇 |
1988年 | 39篇 |
1987年 | 29篇 |
1986年 | 34篇 |
1985年 | 37篇 |
1984年 | 15篇 |
1983年 | 18篇 |
1982年 | 8篇 |
1981年 | 7篇 |
1980年 | 4篇 |
1979年 | 2篇 |
1971年 | 1篇 |
1957年 | 3篇 |
1936年 | 4篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
Song Zi-Long Zhu Yun Liu Jing-Rui Guo Shu-Ke Gu Yu-Cheng Han Xinya Dong Hong-Qiang Sun Qi Zhang Wei-Hua Zhang Ming-Zhi 《Molecular diversity》2021,25(1):205-221
Molecular Diversity - Based on the strategy of diversity-oriented synthesis and the structures of natural product pimprinine and streptochlorin, two series of novel pimprinine derivatives... 相似文献
2.
Guo Jiayun Ma Dongge Sun Fulin Zhuang Guilin Wang Qi Al-Enizi Abdullah M. Nafady Ayman Ma Shengqian 《中国科学:化学(英文版)》2022,65(9):1704-1709
Science China Chemistry - The heterojunction constructed of covalent organic frameworks (COFs) with adjustable structure and other photocatalysts has great potential in the field of photocatalysis.... 相似文献
3.
Hongjin Wang Tengfei Long Hao Zhang Meng Li Qi Sun Xin Zhai Lixin Sun 《Biomedical chromatography : BMC》2022,36(4):e5301
3,4-Difluorobenzyl(1-ethyl-5-(4-((4-hydroxypiperidin-1-yl)-methyl)thiazol-2-yl)-1H-indol-3-yl)carbamate (NAI59), a small molecule with outstanding therapeutic effectiveness to anti-pulmonary fibrosis, was developed as an autotaxin inhibitor candidate compound. To evaluate the pharmacokinetics and plasma protein binding of NAI59, a UPLC–MS/MS method was developed to quantify NAI59 in plasma and phosphate-buffered saline. The calibration curve linearity ranged from 9.95 to 1990.00 ng/mL in plasma. The accuracy was −6.8 to 5.9%, and the intra- and inter-day precision was within 15%. The matrix effect and recovery, as well as dilution integrity, were within the criteria. The chromatographic and mass spectrometric conditions were also feasible to determine phosphate-buffered saline samples, and it has been proved that this method exhibits good precision and accuracy in the range of 9.95–497.50 ng/mL in phosphate-buffered saline. This study is the first to determine the pharmacokinetics, absolute bioavailability, and plasma protein binding of NAI59 in rats using this established method. Therefore, the pharmacokinetic profiles of NAI59 showed a dose-dependent relationship after oral administration, and the absolute bioavailability in rats was 6.3%. In addition, the results of protein binding showed that the combining capacity of NAI59 with plasma protein attained 90% and increased with the increase in drug concentration. 相似文献
4.
Chen Zi-Han Li Yue-Hua Qi Ming-Yu Tang Zi-Rong Xu Yi-Jun 《Research on Chemical Intermediates》2022,48(1):1-12
Research on Chemical Intermediates - Owing to the simultaneous utilization of photogenerated electrons and holes, coupling light-driven hydrogen (H2) evolution reaction (HER) and biomass-derived... 相似文献
5.
Yujie Gao Zhiye Qiu Lei Liu Mengmeng Li Bingjie Xu Dan Yu Dongming Qi Jindan Wu 《Journal of polymer science. Part A, Polymer chemistry》2022,60(15):2191-2212
Refractory wounds have always been an important issue to healthcare systems, whose healing process is always delayed by multiple factors, including bacterial infections, chronic inflammation, and excessive exudates, etc. Employing multifunctional wound dressings is recognized as an effective strategy to deal with refractory wounds, which has yielded promising outcomes in recent years. Among these advanced wound dressings, fibrous dressings have gained growing attention due to their unique merits. Such wound dressings have demonstrated great potential in delivering theranostic agents, such as antibacterial agents, anti-inflammatory drugs, growth factors, and diagnostic probes, etc., for the purposes of accelerating wound healing. This paper reviews the development of multifunctional fibrous dressings and their applications in treating refractory wounds. The construction approaches of novel fibrous dressing with capabilities of antibacterial, anti-inflammation, exudate management and diagnosis were also introduced. Furthermore, the existing problems and challenges are also discussed briefly. 相似文献
6.
Guzev M. A. Liu W. Qi Ch. Riabokon E. P. 《Journal of Applied Mechanics and Technical Physics》2021,62(5):736-741
Journal of Applied Mechanics and Technical Physics - A self-equilibrated stress field for an incompressible sphere is constructed based on a non-Euclidean continuum model. The... 相似文献
7.
8.
Fluid Dynamics - The collapse of cavitation bubbles in a hydraulic system generates localized zones of high temperature and pressure and, under certain conditions, luminescence. In this study, we... 相似文献
9.
随着光伏行业的快速发展, 对硅单晶的品质和长晶装备的稳定性的要求也不断提高。直拉法是生产硅单晶的主要方法,通过提高单晶炉副室的高度以扩大单晶硅的生产规模。由于副室高度的大幅增加,且单晶炉提拉头质心相对于旋转轴心有一定距离,对单晶炉整体稳定性有较大影响,从而降低了单晶硅的生产质量。针对此问题,对单晶炉建立可靠的力学分析模型,采用数值仿真方法,对单晶炉整体进行动力学响应分析,计算得到副室高度增加后的单晶炉工作时中钨丝绳下端晶棒的运动规律以及最大摆动幅度,为改进设计提供依据。数值仿真分析表明提高单晶炉副室高度后,提拉头较大的质心偏心是单晶炉提拉系统发生摆动的主要原因。在此基础上提出在提拉头上添加质心调节装置,通过控制系统调节可保证提拉头质心位置在旋转轴线上以降低提拉系统的摆动。 相似文献
10.
Wang Zhenya Chen Hui Yao Ligang Chen Xu Qi Xiaoli Zhang Jun 《Nonlinear dynamics》2021,106(3):2107-2130
Nonlinear Dynamics - Fault diagnosis of critical rotating machinery components is necessary to ensure safe operation. However, the commonly used rotating machinery fault diagnosis methods are... 相似文献