全文获取类型
收费全文 | 148篇 |
免费 | 2篇 |
国内免费 | 1篇 |
专业分类
化学 | 72篇 |
力学 | 8篇 |
数学 | 28篇 |
物理学 | 43篇 |
出版年
2022年 | 3篇 |
2021年 | 6篇 |
2020年 | 9篇 |
2019年 | 5篇 |
2018年 | 7篇 |
2017年 | 5篇 |
2016年 | 4篇 |
2015年 | 6篇 |
2014年 | 7篇 |
2013年 | 14篇 |
2012年 | 12篇 |
2011年 | 7篇 |
2010年 | 7篇 |
2009年 | 6篇 |
2008年 | 7篇 |
2007年 | 2篇 |
2006年 | 2篇 |
2005年 | 1篇 |
2004年 | 3篇 |
2003年 | 2篇 |
2002年 | 4篇 |
1999年 | 1篇 |
1996年 | 3篇 |
1995年 | 1篇 |
1993年 | 5篇 |
1992年 | 5篇 |
1991年 | 2篇 |
1990年 | 1篇 |
1989年 | 1篇 |
1988年 | 2篇 |
1987年 | 1篇 |
1986年 | 1篇 |
1981年 | 1篇 |
1980年 | 1篇 |
1979年 | 3篇 |
1977年 | 1篇 |
1976年 | 1篇 |
1975年 | 2篇 |
排序方式: 共有151条查询结果,搜索用时 31 毫秒
111.
Evidence for the electron-electron scattering contribution to the electrical resistivity of aluminum
It is demonstrated that the recent low-temperature electrical resistivity data for aluminum provide experimental evidence for the presence of a T2 contribution to the electrical resistivity due to electron-electron scattering. 相似文献
112.
113.
114.
115.
116.
Dr. Ayan Dasgupta Yara van Ingen Michael G. Guerzoni Dr. Kaveh Farshadfar Prof. Jeremy M. Rawson Dr. Emma Richards Prof. Alireza Ariafard Prof. Rebecca L. Melen 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(45):e202201422
An efficient and mild reaction protocol for the decarbonylation of isocyanates has been developed using catalytic amounts of Lewis acidic boranes. The electronic nature (electron withdrawing, electron neutral, and electron donating) and the position of the substituents (ortho/meta/para) bound to isocyanate controls the chain length and composition of the products formed in the reaction. Detailed DFT studies were undertaken to account for the formation of the mono/di-carboxamidation products and benzoxazolone compounds. 相似文献
117.
Sara Tavakkoli Fard Dr. Kohei Sekine Dr. Kaveh Farshadfar Dr. Frank Rominger Dr. Matthias Rudolph Dr. Alireza Ariafard Prof. Dr. A. Stephen K. Hashmi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(10):3552-3559
A simple gold-catalyzed annulation of 1,8-dialkynylnaphthalenes utilizing a cationic gold catalyst was developed. Such a peri-position of two alkynyl substituents has not been studied in gold catalysis before. Dependent on the substrate, the reactions either follow a mechanism involving vinyl cation intermediates or involve a dual gold catalysis mechanism which in an initial 6-endo-dig-cyclization generates gold(I) vinylidene intermediates that are able to insert into C−H bonds. Indenophenalene derivatives were obtained in moderate to high yields. In addition, the bidirectional gold-catalyzed annulation of tetraynes provided even larger conjugated π-systems. The optoelectronic properties of the products were also investigated. 相似文献
118.
The effect of cationic template on the adsorption of copper-phthalocyanine-3,4’,4",4"’-tetrasulfonic acid tetra- 相似文献
119.
By a $\mathfrak{B}$ -regular variety, we mean a smooth projective variety over $\mathbb{C}$ admitting an algebraic action of the upper triangular Borel subgroup $\mathfrak{B} \subset {\text{SL}}_{2} {\left( \mathbb{C} \right)}$ such that the unipotent radical in $\mathfrak{B}$ has a unique fixed point. A result of Brion and the first author [4] describes the equivariant cohomology algebra (over $\mathbb{C}$ ) of a $\mathfrak{B}$ -regular variety X as the coordinate ring of a remarkable affine curve in $X \times \mathbb{P}^{1}$ . The main result of this paper uses this fact to classify the $\mathfrak{B}$ -invariant subvarieties Y of a $\mathfrak{B}$ -regular variety X for which the restriction map i Y : H *(X) → H *(Y) is surjective. 相似文献
120.
In the present study, CoFe2O4@SiO2@CPTMS nanocomposite was synthesized and the homogeneous chiral Mn‐salen complex was anchored covalently onto the surface of CoFe2O4@SiO2@CPTMS nanocomposite. The heterogeneous Mn‐salen magnetic nanocatalyst (CoFe2O4@SiO2@CPTMS@ chiral Mn (III) Complex) was characterized by different techniques including transmission electron microscopy (TEM), Fourier transform infrared (FT‐IR), vibrating sample magnetometer (VSM), scanning electron microscopy (SEM), powder X‐ray diffraction (XRD) and thermogravimetric analysis (TGA). Then, the aerobic enantioselective oxidation of olefins to the corresponding epoxide was investigated in the presence of magnetic chiral CoFe2O4@SiO2@Mn (III) complex at ambient conditions within 90 min. The results showed the corresponding products were synthesized with excellent yields and selectivity. In addition, the heterogeneous CoFe2O4@SiO2@ CPTMS@ chiral Mn (III) complex has benefits such as high selectivity and comparable catalytic reactivity with its homogeneous analog as well as mild reaction condition, facile recovery, and recycling of the heterogeneous catalyst. 相似文献