全文获取类型
收费全文 | 2681篇 |
免费 | 225篇 |
国内免费 | 135篇 |
专业分类
化学 | 1823篇 |
晶体学 | 34篇 |
力学 | 114篇 |
综合类 | 9篇 |
数学 | 397篇 |
物理学 | 664篇 |
出版年
2023年 | 38篇 |
2022年 | 36篇 |
2021年 | 68篇 |
2020年 | 97篇 |
2019年 | 100篇 |
2018年 | 90篇 |
2017年 | 70篇 |
2016年 | 143篇 |
2015年 | 105篇 |
2014年 | 139篇 |
2013年 | 198篇 |
2012年 | 188篇 |
2011年 | 220篇 |
2010年 | 129篇 |
2009年 | 116篇 |
2008年 | 144篇 |
2007年 | 141篇 |
2006年 | 148篇 |
2005年 | 115篇 |
2004年 | 85篇 |
2003年 | 58篇 |
2002年 | 58篇 |
2001年 | 46篇 |
2000年 | 47篇 |
1999年 | 30篇 |
1998年 | 26篇 |
1997年 | 23篇 |
1996年 | 26篇 |
1995年 | 34篇 |
1994年 | 24篇 |
1993年 | 23篇 |
1992年 | 26篇 |
1991年 | 27篇 |
1990年 | 15篇 |
1989年 | 10篇 |
1988年 | 15篇 |
1987年 | 16篇 |
1986年 | 13篇 |
1985年 | 21篇 |
1984年 | 15篇 |
1983年 | 10篇 |
1982年 | 15篇 |
1981年 | 14篇 |
1980年 | 11篇 |
1979年 | 9篇 |
1978年 | 9篇 |
1977年 | 9篇 |
1976年 | 8篇 |
1974年 | 7篇 |
1973年 | 6篇 |
排序方式: 共有3041条查询结果,搜索用时 181 毫秒
1.
Mathematical Programming - In the general equilibrium with incomplete asset markets (GEI) model, the excess demand functions are typically not continuous at the prices for which the assets have... 相似文献
2.
Anh Ha Lan Nhan Dang Duc Frew Russell Quynh Tran Minh 《Journal of Radioanalytical and Nuclear Chemistry》2022,331(9):3613-3621
Journal of Radioanalytical and Nuclear Chemistry - This research aimed to authenticate the geographical origin of imported fresh apples using isotopic techniques. The results show that the... 相似文献
3.
Dang Huyen Vu Xuan Dang Hanh Vu Bich Doan Huu Dung Nguyen Tan Phong 《Research on Chemical Intermediates》2022,48(3):1311-1311
Research on Chemical Intermediates - 相似文献
4.
将TiNi基记忆合金薄膜与光纤相结合可制成智能化、集成化且成本经济的微机电系统和微传感器件.本文采用磁控溅射法在二氧化硅光纤基底上制备TiNi记忆合金薄膜,系统讨论了溅射工艺参数以及后续退火处理对薄膜质量的影响.采用自研制光纤镀膜掩膜装置在直径为125μm的光纤圆周表面上形成均匀薄膜.实验表明:在靶基距、背底真空度、Ar气流量和溅射时间一定的条件下,溅射功率存在最佳值;溅射压强较大时,薄膜沉积速率较低,但薄膜表面粗糙度较小.进行退火处理后,薄膜形成较良好的晶体结构,Ti49.09Ni50.91薄膜中马氏体B19′相和奥氏体B2相共存,但以B19′为主.根据本文研究结果,在玻璃光纤基底上制备高质量的TiNi基记忆合金薄膜是可实现的,本工作为下一步研制微机电系统和微型传感器做了基础准备. 相似文献
5.
Bao Nguyen Xuan Duy Khanh Phan Quoc Tung Nguyen Minh 《Set-Valued and Variational Analysis》2022,30(2):465-486
Set-Valued and Variational Analysis - We aim to establish Karush-Kuhn-Tucker multiplier rules involving higher-order complementarity slackness under Hölder metric subregularity. These rules... 相似文献
6.
Gitae Moon Intae Son Chunho Kim Chi Hyeong Cho Eunbi Lee Eun Hyoung Bae 《Molecular Crystals and Liquid Crystals》2019,687(1):60-67
AbstractTo enable recent 3D and moving picture applications, liquid crystal displays (LCD) must exhibit fast response and wide viewing angle characteristics. Pre-tilted vertical alignment layers for high-speed LCD were fabricated using bi-functional photoreactive monomers. The monomers can be confined to the polyimide layer and photo-polymerized by UV exposure under voltage. Response characteristics of photo-controlled alignment films according to the structure were investigated. Vertical alignment properties were evaluated using a polarizing optical microscope, and electro-optical characteristics were compared through the voltage-transmittance curve and response time measurement. Faster response speed could be obtained by using photoreactive monomers having a long alkyl chain. 相似文献
7.
Although bilobetin, a biflavone isolated from the leaves of Ginkgo biloba, represents a variety of pharmacological activities, to date there have been no validated determination methods for bilobetin in biological samples. Thus, we developed a liquid chromatographic method using a tandem mass spectrometry for the determination of bilobetin in rat plasma. After protein precipitation with acetonitrile including diclofenac (internal standard), the analytes were chromatographed on a reversed-phased column with a mobile phase of purified water and acetonitrile (3:7, v/v, including 0.1% formic acid). The ion transitions of the precursor to the product ion were principally deprotonated ions [M − H]− at m/z 551.2 → 519.2 for bilobetin and 296.1 → 251.7 for the IS. The accuracy and precision of the assay were in accordance with US Food and Drug Administration regulations for the validation of bioanalytical methods. This analytical method was successfully applied to monitor plasma concentrations of bilobetin over time following intravenous administration in rats. 相似文献
8.
9.
Journal of Mathematical Chemistry - Deficiency zero is an important network structure and has been the focus of many celebrated results within reaction network theory. In our previous paper... 相似文献
10.
Journal of Statistical Physics - In this paper, we will study the long time behavior of the simple symmetric exclusion process in the “channel” $$\varLambda _N=[1,N]\cap \mathbb {N}$$... 相似文献