全文获取类型
收费全文 | 1417篇 |
免费 | 70篇 |
国内免费 | 31篇 |
专业分类
化学 | 446篇 |
晶体学 | 29篇 |
力学 | 15篇 |
综合类 | 7篇 |
数学 | 201篇 |
物理学 | 820篇 |
出版年
2023年 | 7篇 |
2022年 | 8篇 |
2021年 | 8篇 |
2020年 | 6篇 |
2019年 | 18篇 |
2018年 | 10篇 |
2017年 | 7篇 |
2016年 | 10篇 |
2015年 | 8篇 |
2014年 | 10篇 |
2013年 | 35篇 |
2012年 | 6篇 |
2011年 | 9篇 |
2010年 | 19篇 |
2009年 | 98篇 |
2008年 | 134篇 |
2007年 | 111篇 |
2006年 | 103篇 |
2005年 | 79篇 |
2004年 | 82篇 |
2003年 | 89篇 |
2002年 | 79篇 |
2001年 | 87篇 |
2000年 | 75篇 |
1999年 | 57篇 |
1998年 | 44篇 |
1997年 | 25篇 |
1996年 | 27篇 |
1995年 | 28篇 |
1994年 | 41篇 |
1993年 | 22篇 |
1992年 | 24篇 |
1991年 | 11篇 |
1990年 | 9篇 |
1989年 | 20篇 |
1988年 | 7篇 |
1987年 | 7篇 |
1986年 | 8篇 |
1985年 | 6篇 |
1984年 | 9篇 |
1983年 | 4篇 |
1982年 | 5篇 |
1981年 | 12篇 |
1980年 | 9篇 |
1979年 | 12篇 |
1978年 | 10篇 |
1977年 | 10篇 |
1976年 | 5篇 |
1975年 | 3篇 |
1973年 | 3篇 |
排序方式: 共有1518条查询结果,搜索用时 0 毫秒
1.
K. Batra V. Prasad M. Mohan 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2002,20(2):191-198
The scattering of heavy ion with a multilevel Rydberg atom in the presence of an electromagnetic field is studied. The interaction
of Rydberg atom and the e.m field is explored using non-perturbative quasi-energy technique. Although the results are presented
for selected excitations but in actual calculations we have included many levels of the atom. The effect of various parameters
are shown on collisional excitation process. As an illustration detailed calculations are performed for the inelastic proton-Na
Rydberg atom collision accompanied by the transfer of photons and the effects of dressing due to the field are considered.
The emphasis of the present work is on collision induced transitions especially the case that involves change of orbital as
well as principal quantum number.
Received 26 December 2001 / Received in final form 8 April 2002 Published online 19 July 2002 相似文献
2.
S. Mancini D. Vitali V. Giovannetti P. Tombesi 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2003,22(3):417-422
We show that the optomechanical coupling between an optical cavity mode and two movable cavity mirrors is able to entangle
two different macroscopic oscillation modes of the mirrors. This continuous variable entanglement is maintained by the light
bouncing between the mirrors and is robust against thermal noise. In fact, it could be experimentally demonstrated using present
technology.
Received 2 September 2002 / Received in final form 10 October 2002 Published online 7 January 2003 相似文献
3.
In this paper, we first reduce the problem of finding a minimum parity (gt;ggt;,gt;fgt;)-factor of a graph gt;Ggt; into the problem of finding a minimum perfect matching in a weighted simple graph gt;Ggt;*. Using the structure of gt;Ggt;*, a necessary and sufficient condition for the existence of an even factor is derived.
This paper was accomplished while the second author was visiting the Center for Combinatorics, Nankai University.
The research is supported by NSFC 相似文献
4.
The discovery of the neutrino oscillation pattern with solar and atmospheric neutrinos has stimulated systematic studies with long-baseline accelerator experiments. Precise neutrino beamline calculations have demonstrated the importance and paucity of existing hadroproduction data needed to shape the primary meson production in targets and tune available Monte Carlo codes for hadronic shower simulation. After a brief introduction to the physics of neutrino beams, available hadron production data will be reviewed with regards to their parametrization. Fast simulations based on such parameterizations and full Monte Carlo simulations of neutrino beamlines will then be illustrated. The prospective impact of new hadroproduction experiments, such as HARP at CERN and MIPP at Fermilab, will be shown together with some neutrino beamline simulations. 相似文献
5.
We have prepared composite magnetic core–shell particles using the process of soap-free emulsion polymerization and the co-precipitation method. The shell of the synthesized composite sphere is cobalt ferrite (CoFegt;2gt;Ogt;4gt;) nanoparticles and the core consists of poly(styrene-co-methacrylic acid) polymer. The mean crystallite sizes of the coated CoFegt;2gt;Ogt;4gt; nanoparticles were controlled in the range of 2.4–6.7 nm by the concentration of [NHgt;4gt;gt;+gt;] and heated temperature. The magnetic properties of the core–shell spherical particles can go from superparamagnetic to ferromagnetic behavior depending on the crystalline sizes of CoFegt;2gt;Ogt;4gt;. 相似文献
6.
Luis Anchordoqui María Teresa Dova Thomas McCauley Stephen Reucroft 《Annals of Physics》2004,314(1):145-207
The properties of cosmic rays with energies above 10gt;6gt; GeV have to be deduced from the spacetime structure and particle content of the air showers which they initiate. In this review we summarize the phenomenology of these giant air showers. We describe the hadronic interaction models used to extrapolate results from collider data to ultra high energies, and discuss the prospects for insights into forward physics at the LHC. We also describe the main electromagnetic processes that govern the longitudinal shower evolution, as well as the lateral spread of particles. Armed with these two principal shower ingredients and motivation from the underlying physics, we provide an overview of some of the different methods proposed to distinguish primary species. The properties of neutrino interactions and the potential of forthcoming experiments to isolate deeply penetrating showers from baryonic cascades are also discussed. We finally venture into a gt;terra incognitagt; endowed with TeV-scale gravity and explore anomalous neutrino-induced showers. 相似文献
7.
D.E. ShalómH. Pastoriza 《Solid State Communications》2003,126(7):379-383
We present kinetic inductance measurements in current driven Josephson junction arrays. Measurements performed with circular coils indicate that this technique is very sensitive to the vortex mobility. Results obtained with anisotropic detection coils provide experimental evidence for the anisotropic response of a driven vortex lattice. Anisotropic behavior is obtained when rising the temperature or the mean vortex velocity as indicated by the loss of the superconducting shielding capability, first in the direction of vortex motion and then in the perpendicular direction. 相似文献
8.
H. Maekawa K. Tsubakihara A. Ohnishi 《The European Physical Journal A - Hadrons and Nuclei》2007,33(3):269-272
We study the hyperon-nucleus potential with distorted-wave impulse wave approximation (DWIA) using the Green's function method.
In order to include the nucleon and hyperon potential effects in Fermi averaging, we introduce the local optimal momentum
approximation of target nucleons. We can describe the quasi-free Λ , Σ and Ξ production spectra in a better way than in the
standard Fermi-averaged gt;tgt; -matrix treatments. 相似文献
9.
gt;35gt;Cl NQR as well as heat capacity measurements of [(PyO)H][AuClgt;4gt;] and its deuterated analog [(PyO)D][AuClgt;4gt;] revealed successive phase transitions at 70.5 and 62.5 K, and at 71 and 63 K, respectively. The NQR frequency varied continuously through the upper transition point while discontinuously through the lower transition point. In the intermediate-temperature phase a remarkable decrease in the signal intensity was observed. These NQR observations as well as the feature of the heat capacity anomaly in which a broad peak is succeeded by a sharp peak with decreasing temperature suggest a possibility of normal-incommensurate-commensurate phase sequence. 相似文献
10.
M. A. Macrì C. Del Gratta L. Di Donato S. Di Luzio G. L. Romani S. Della Penna A. Pasquarelli 《Il Nuovo Cimento D》1994,16(5):425-432
Summary A preliminary study is here reported on a new potential marker for biomagnetic measurements. The marker consists of superparamagnetic
polymer microspheres which were detected in the presence of external steady magnetic fields by means of an r.f.-SQUID magnetometer.
The particles were prepared in samples differing in the concentration value and immersed in a homogeneous magnetic field of
variable intensity. A simple model was taken into account for the distribution of the microspheres in the samples, so that
the theoretical values were compared to the marker field values measured by the biomagnetic sensor. The overall sensitivity
of the experimental apparatus and the minimum concentration value of the marker were then estimated. 相似文献