全文获取类型
收费全文 | 40885篇 |
免费 | 1185篇 |
国内免费 | 674篇 |
专业分类
化学 | 21201篇 |
晶体学 | 641篇 |
力学 | 1946篇 |
综合类 | 26篇 |
数学 | 4150篇 |
物理学 | 14780篇 |
出版年
2022年 | 353篇 |
2021年 | 495篇 |
2020年 | 508篇 |
2019年 | 504篇 |
2018年 | 689篇 |
2017年 | 580篇 |
2016年 | 968篇 |
2015年 | 618篇 |
2014年 | 954篇 |
2013年 | 1933篇 |
2012年 | 1934篇 |
2011年 | 2274篇 |
2010年 | 1626篇 |
2009年 | 1610篇 |
2008年 | 1817篇 |
2007年 | 1739篇 |
2006年 | 1610篇 |
2005年 | 1394篇 |
2004年 | 1309篇 |
2003年 | 1137篇 |
2002年 | 1063篇 |
2001年 | 1451篇 |
2000年 | 1056篇 |
1999年 | 897篇 |
1998年 | 673篇 |
1997年 | 653篇 |
1996年 | 579篇 |
1995年 | 527篇 |
1994年 | 484篇 |
1993年 | 434篇 |
1992年 | 490篇 |
1991年 | 505篇 |
1990年 | 493篇 |
1989年 | 446篇 |
1988年 | 441篇 |
1987年 | 431篇 |
1986年 | 379篇 |
1985年 | 448篇 |
1984年 | 466篇 |
1983年 | 346篇 |
1982年 | 389篇 |
1981年 | 375篇 |
1980年 | 312篇 |
1979年 | 394篇 |
1978年 | 375篇 |
1977年 | 392篇 |
1976年 | 390篇 |
1975年 | 340篇 |
1974年 | 319篇 |
1973年 | 334篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
Chuprin A. S. Belova S. A. Bugaenko M. G. Vologzhanina A. V. Loktev A. S. Voloshin Ya. Z. Buznik V. M. Dedov A. G. 《Kinetics and Catalysis》2022,63(1):108-116
Kinetics and Catalysis - A new ruthenium(II) cage complex with polar terminal groups in the apical substituents has been synthesized; the molecular design of the complex contributes to the... 相似文献
2.
High Energy Chemistry - Modification of Polyvinylidene fluoride (PVDF) by radiation grafting is a research hotspot in recent years. In this study, the monomer 2-Hydroxyethyl methacrylate (HEMA) was... 相似文献
3.
Alawainati F. A. Manaa H. Henari F. Z. Biyiklioglu Z. Arslan T. Jaafar A. 《Journal of Applied Spectroscopy》2021,88(5):951-957
Journal of Applied Spectroscopy - Detailed measurements of nonlinear optical properties and optical limiting for four phthalocyanine (Pc) derivatives (PcCo, PcCu, PcMn, and PcSi) are reported. The... 相似文献
4.
Siberian Mathematical Journal - A lattice homomorphism between quasi-Banach lattices is known to be compact if and only if it is a sum of a series of rank one lattice... 相似文献
5.
Donglei Wei Huili Li Chuanqing Yang Jianmin Fu Hou Chen Liangjiu Bai Wenxiang Wang Huawei Yang Lixia Yang Ying Liang 《Journal of polymer science. Part A, Polymer chemistry》2022,60(10):1588-1594
Acridone as a new kind of visible light photocatalyst has been developed to catalyze metal free atom transfer radical polymerization (ATRP). The photocatalyst possess low excited state potential as can undergo an oxidative quenching pathway to initiate ATRP of vinyl monomers. Kinetic study and light on/off reaction demonstrate the “living”/controlled nature of the polymerization by light. Block copolymers can be achieved by using PMMA as macroinitiator to reinitiate polymerization of other vinyl monomers, which shows highly preserved Br chain-end functionality in the synthesized polymers. Moreover, the polymerization can be conducted under air atmosphere as most photocatalysts need anaerobic condition, which may give inspiration of further application of this kind of photocatalyst. 相似文献
6.
7.
Nanocomposite hydrogel consisting of Na‐montmorillonite with enhanced mechanical properties 下载免费PDF全文
Ting Li Shuangfei Xiang Piming Ma Huiyu Bai Weifu Dong Mingqing Chen 《Journal of Polymer Science.Polymer Physics》2015,53(14):1020-1026
A new kind of nanocomposite (NC) hydrogel with Na‐montmorillonite (MMT) is presented in this article. The NC hydrogels were synthesized by free radical copolymerization of acrylamide and (3‐acrylamidopropyl) trimethylammonium chloride (ATC) in the presence of MMT and N,N′‐methylene‐bis‐acrylamide used as chemical cross‐linker. Due to the cation‐exchange reaction between MMT and ATC (cationic monomer) during the synthesis of NC hydrogels, MMT platelets were considered chemical “plane” cross‐linkers, different from “point” cross‐linkers. With increasing amount of MMT, the crosslinking degree enhanced, causing a decrease of the swelling degree at equilibrium. Investigations of mechanical properties indicated that NC hydrogels exhibited enhanced strength and toughness, which resulted from chemical interaction between exfoliated MMT platelets and polymer chains in hydrogels. Dynamic shear measurements showed that both storage modulus and loss modulus increased with increasing MMT content. The idea described here provided a new route to prepare hydrogels with high mechanical properties by using alternative natural Na‐MMT. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2015 , 53, 1020–1026 相似文献
8.
We study the full counting statistics of transport electrons through a semiconductor two-level quantum dot with Rashba spin–orbit (SO) coupling, which acts as a nonabelian gauge field and thus induces the electron transition between two levels along with the spin flip. By means of the quantum master equation approach, shot noise and skewness are obtained at finite temperature with two-body Coulomb interaction. We particularly demonstrate the crucial effect of SO coupling on the super-Poissonian fluctuation of transport electrons, in terms of which the SO coupling can be probed by the zero-frequency cumulants. While the charge currents are not sensitive to the SO coupling. 相似文献
9.
Analysis and pharmacokinetic study of polyphyllin H in beagle dog plasma after oral administration of Rhizoma Paridis Extracts by LC‐MS/MS 下载免费PDF全文
10.