全文获取类型
收费全文 | 57篇 |
免费 | 13篇 |
国内免费 | 37篇 |
专业分类
化学 | 42篇 |
力学 | 7篇 |
综合类 | 3篇 |
数学 | 2篇 |
物理学 | 53篇 |
出版年
2023年 | 6篇 |
2022年 | 5篇 |
2021年 | 5篇 |
2020年 | 5篇 |
2019年 | 4篇 |
2018年 | 4篇 |
2017年 | 1篇 |
2016年 | 2篇 |
2015年 | 3篇 |
2014年 | 9篇 |
2013年 | 3篇 |
2012年 | 3篇 |
2011年 | 6篇 |
2010年 | 6篇 |
2009年 | 6篇 |
2008年 | 4篇 |
2007年 | 4篇 |
2006年 | 8篇 |
2005年 | 4篇 |
2004年 | 1篇 |
2003年 | 3篇 |
2002年 | 6篇 |
2001年 | 4篇 |
1999年 | 3篇 |
1956年 | 1篇 |
1954年 | 1篇 |
排序方式: 共有107条查询结果,搜索用时 15 毫秒
21.
We investigate a matter dominated navigation cosmological model.The influence of a possible drift(wind) in the navigation cosmological model makes the spacetime geometry change from Riemannian to Finslerian.The evolution of the Finslerian Universe is governed by the same gravitational field equation with the familiar Friedmann-Robertson-Walker one.However,the change of space geometry from Riemannian to Finslerian supplies us a new relation between the luminosity distant and redshift.It is shown that the Hubble diagram based on this new relation could account for the observations on distant Type Ia supernovae. 相似文献
22.
Gravitational field equations in Randers-Finsler space of approximate Berwald type are investigated. A modified Friedmann equation and a new luminosity distance-redshift relation is proposed. A best-fit to the Type Ia supernovae (SNe) observations yields that the ΩΛ in the Λ-CDM model is suppressed to almost zero. This fact indicates that the astronomical observations on the Type Ia SNe can be described well without invoking any form of dark energy. The best-fit age of the universe is given. It is in agreement with the age of our galaxy. 相似文献
23.
Based on the solvable spin-1/2 Heisenberg chain we demonstrate how two many-body systems are entangled due to their partial entanglement. The entanglement wave in the two spin chains displays a damped oscillation if the spin number is N 〉 3, and only propagates with a certain velocity depending on the coupling constant J. Moreover, the entanglement wave will be reflected on the other ends of the two spin chains. A simple scheme for transferring some special two-qubit states to other two distant qubits is also proposed. 相似文献
24.
25.
We probe the universality of acceleration scale a0 in Milgrom's modified Newtonian dynamics(MOND)using the recently released rotation curve data from SPARC galaxies.We divide the SPARC data into different subsamples according to the morphological types of galaxies,and fit the rotation curve data of each subsample with the theoretical prediction of MOND.MOND involves an arbitrary interpolation function which connects the Newtonian region and the MOND region.Here we consider five different interpolation functions that are widely discussed in the literature.It is shown that the best-fitting a0 significantly depends on the interpolation functions.For a specific interpolation function, a0 also depends on the morphological types of galaxies,implying that a0 may be not a universal constant.Introducing a dipole correction to a0 can significantly improve the fits.The dipole directions for four of the five interpolation functions point towards an approximately consistent direction,but a0 still varies for different interpolation functions. 相似文献
26.
27.
28.
29.
30.
用具有恒定温度环境的反应热量计,以 4 m ol· L- 1 H Cl溶液为量热溶剂,测得8羟基喹啉与醋酸钴固相反应焓Δr Hm = 29.68 k J·m ol- 1,计算了配合物 Co(oxin)2 ·2 H2 O 的标准生成焓Δf Hm = - 764.6 k J·m ol 相似文献