全文获取类型
收费全文 | 312篇 |
免费 | 12篇 |
国内免费 | 2篇 |
专业分类
化学 | 211篇 |
晶体学 | 5篇 |
力学 | 9篇 |
综合类 | 2篇 |
数学 | 32篇 |
物理学 | 67篇 |
出版年
2023年 | 5篇 |
2022年 | 7篇 |
2021年 | 8篇 |
2020年 | 11篇 |
2019年 | 12篇 |
2018年 | 11篇 |
2017年 | 6篇 |
2016年 | 10篇 |
2015年 | 19篇 |
2014年 | 15篇 |
2013年 | 26篇 |
2012年 | 18篇 |
2011年 | 34篇 |
2010年 | 11篇 |
2009年 | 9篇 |
2008年 | 15篇 |
2007年 | 15篇 |
2006年 | 11篇 |
2005年 | 19篇 |
2004年 | 7篇 |
2003年 | 11篇 |
2002年 | 5篇 |
2001年 | 5篇 |
2000年 | 1篇 |
1999年 | 4篇 |
1998年 | 4篇 |
1997年 | 2篇 |
1996年 | 1篇 |
1995年 | 1篇 |
1993年 | 2篇 |
1992年 | 1篇 |
1991年 | 2篇 |
1990年 | 2篇 |
1989年 | 1篇 |
1986年 | 1篇 |
1985年 | 2篇 |
1983年 | 2篇 |
1980年 | 1篇 |
1979年 | 2篇 |
1978年 | 1篇 |
1977年 | 1篇 |
1976年 | 3篇 |
1974年 | 1篇 |
1972年 | 1篇 |
排序方式: 共有326条查询结果,搜索用时 31 毫秒
91.
A new τ_method is presented for the two dimensional linear boundary value problems. Theoretical and numerical analyses are presented. These results indicate that our method works nicely and efficiently. 相似文献
92.
93.
The Jones–Dole B coefficients of the electrolyte Lithium bromide (LiBr), reference salts tetra butyl ammonium tetra phenyl borate (BU4NBPh4), tetra butyl ammonium bromide (BU4NBr), and potassium chloride (KCl) in dimethylsulfoxide (DMSO), water, and DMSO–water mixtures were obtained at different
temperatures range from 25 to 45 °C For this, the relative viscosities were measured for Lithium bromide (LiBr) and reference
salts in DMSO, water, and DMSO–water mixtures at above-mentioned temperatures. The B coefficients of these electrolytes were behaved as structure makers in DMSO, while in H2O and DMSO–H2O mixtures, the B-coefficient values were less positive showing the weak structure-making effect. Ionic viscosity B coefficients allow us to assess the behavior of ions in the solvent mixtures. In this study it was observed that all the
values of ionic B coefficient of (Li+) were positive and small showing the weak structure-making effects. It was also observed that Br− ions maintain negative B coefficient values in all DMSO–H2O mixtures, except in 60% DMSO mole fraction. From this it can be concluded that Br− ion behaved as a structure breaker in water and in all DMSO–H2O mixtures except in 60% DMSO mole fraction mixtures. The low B
± values of alkali metal ions and Br− ions in water are due to the breakdown of the tetrahedral structural of water and the formation of strongly structured solvated
ion. It is also observed that the values of the energy of activation of the flow for LiBr are greater in DMSO–water mixtures
and in pure water than in DMSO. This may be due the presence of a network of hydrogen bonds which cause the hindrance in the
flow of the solution of LiBr in DMSO–water mixtures and in pure water than in DMSO. 相似文献
94.
A. Muhammed Uludağ 《manuscripta mathematica》2001,106(3):271-277
We give a recipe for finding new examples of plane curves with a finite non-abelian fundamental group of the complement and
new examples of Zariski pairs of plane curves.
Received: 18 December 2000 / Revised version: 27 April 2001 相似文献
95.
96.
97.
98.
Muhammed een Jong Min Oh Zeynep
zdemir Saliha Ebru Büyüktuncel Mehtap Uysal Mohamed A. Abdelgawad Arafa Musa Nicola Gambacorta Orazio Nicolotti Bijo Mathew Hoon Kim 《Molecules (Basel, Switzerland)》2020,25(22)
Twelve pyridazinones (T1–T12) containing the (2-fluorophenyl) piperazine moiety were designed, synthesized, and evaluated for monoamine oxidase (MAO) -A and -B inhibitory activities. T6 was found to be the most potent MAO-B inhibitor with an IC50 value of 0.013 µM, followed by T3 (IC50 = 0.039 µM). Inhibitory potency for MAO-B was more enhanced by meta bromo substitution (T6) than by para bromo substitution (T7). For para substitution, inhibitory potencies for MAO-B were as follows: -Cl (T3) > -N(CH3)2 (T12) > -OCH3 (T9) > Br (T7) > F (T5) > -CH3 (T11) > -H (T1). T6 and T3 efficiently inhibited MAO-A with IC50 values of 1.57 and 4.19 µM and had the highest selectivity indices (SIs) for MAO-B (120.8 and 107.4, respectively). T3 and T6 were found to be reversible and competitive inhibitors of MAO-B with Ki values of 0.014 and 0.0071, respectively. Moreover, T6 was less toxic to healthy fibroblast cells (L929) than T3. Molecular docking simulations with MAO binding sites returned higher docking scores for T6 and T3 with MAO-B than with MAO-A. These results suggest that T3 and T6 are selective, reversible, and competitive inhibitors of MAO-B and should be considered lead candidates for the treatment of neurodegenerative disorders like Alzheimer’s disease. 相似文献
99.
Jais Abdul Azim Ali S. A. Muhammed Anwar Mustafa Somalu Mahendra Rao Muchtar Andanastuti Isahak Wan Nor Roslam Wan Baharudin Nurul Akidah Lim Kean Long Brandon Nigel P. 《Journal of Solid State Electrochemistry》2020,24(3):711-722
Journal of Solid State Electrochemistry - Nickel/scandia-ceria-stabilized-zirconia (Ni/10Sc1CeSZ) cermet is a potential anode for solid oxide fuel cells. The anode powder is prepared through a... 相似文献
100.
T. Gamze Ulusoy Ghobadi Amir Ghobadi Muhammed Buyuktemiz Elif Akhuseyin Yildiz Dilara Berna Yildiz H. Gul Yaglioglu Yavuz Dede Ekmel Ozbay Ferdi Karadas 《Angewandte Chemie (International ed. in English)》2020,59(10):4082-4090
Herein, we establish a simple synthetic strategy affording a heterogeneous, precious metal‐free, dye‐sensitized photoelectrode for water oxidation, which incorporates a Prussian blue (PB) structure for the sensitization of TiO2 and water oxidation catalysis. Our approach involves the use of a Fe(CN)5 bridging group not only as a cyanide precursor for the formation of a PB‐type structure but also as an electron shuttle between an organic chromophore and the catalytic center. The resulting hetero‐functional PB‐modified TiO2 electrode demonstrates a low‐cost and easy‐to‐construct photoanode, which exhibits favorable electron transfers with a remarkable excited state lifetime on the order of nanoseconds and an extended light absorption capacity of up to 500 nm. Our approach paves the way for a new family of precious metal‐free robust dye‐sensitized photoelectrodes for water oxidation, in which a variety of common organic chromophores can be employed in conjunction with CoFe PB structures. 相似文献