全文获取类型
收费全文 | 164篇 |
免费 | 3篇 |
国内免费 | 2篇 |
专业分类
化学 | 57篇 |
晶体学 | 2篇 |
力学 | 3篇 |
数学 | 14篇 |
物理学 | 93篇 |
出版年
2022年 | 2篇 |
2019年 | 2篇 |
2018年 | 1篇 |
2017年 | 2篇 |
2016年 | 3篇 |
2015年 | 2篇 |
2014年 | 7篇 |
2013年 | 24篇 |
2012年 | 8篇 |
2011年 | 12篇 |
2010年 | 8篇 |
2009年 | 2篇 |
2008年 | 6篇 |
2007年 | 4篇 |
2006年 | 4篇 |
2005年 | 5篇 |
2004年 | 3篇 |
2003年 | 9篇 |
2002年 | 5篇 |
2001年 | 7篇 |
2000年 | 1篇 |
1999年 | 8篇 |
1998年 | 4篇 |
1997年 | 5篇 |
1996年 | 4篇 |
1995年 | 5篇 |
1994年 | 5篇 |
1993年 | 4篇 |
1992年 | 2篇 |
1990年 | 1篇 |
1987年 | 1篇 |
1985年 | 1篇 |
1981年 | 2篇 |
1979年 | 1篇 |
1968年 | 2篇 |
1957年 | 1篇 |
1939年 | 1篇 |
1934年 | 2篇 |
1933年 | 2篇 |
1867年 | 1篇 |
排序方式: 共有169条查询结果,搜索用时 281 毫秒
41.
We characterize statistical independence of sequences by the L
p-discrepancy and the Wiener L
p-discrepancy. Furthermore, we find asymptotic information on the distribution of the L
2-discrepancy of sequences 相似文献
42.
Structural Interactions of Planar and Non‐planar Bis(1,2‐dithiosquarato)metalate Host Lattices with CuII Complexes – Structure and EPR Investigations 1,2‐Dithiosquaratometalates (M = Cu, Ni, Zn) are available by direct synthesis from metal salts with dipotassium‐1,2‐dithiosquarate. The structural influence of the planar and nonplanar host lattice systems (BzlEt3N)2[Cu/Ni(dtsq)2] and (BzlEt3N)2[Cu/Zn(dtsq)2] on the geometrical and electronic structure of the CuII guest complex [Cu(dtsq)2]2– is studied by EPR spectroscopy. The used host lattices (BzlEt3N)2[Ni(dtsq)2] (planar) and (BzlEt3N)2[Zn(dtsq)2] (tetrahedral) are characterized by X‐ray structure analysis. (BzlEt3N)2[Ni(dtsq)2] crystallizes in the triclinic unit cell P1 with a = 9.1021(8) Å, b = 9.4190(8) Å, c = 11.0119(10) Å, α = 92.8560(10)°, β = 95.375(2)°, γ = 104.5180(10)° and Z = 1. (BzlEt3N)2[Zn(dtsq)2] crystallizes in the monoclinic unit cell C2/c with a = 21.1299(14) Å, b = 16.6641(11) Å, c = 13.8324(9) Å, β = 123.9100(10)° and Z = 4. The g and A Cu tensors in the Cu/Ni system are nearly axial symmetric (g|| = 2.122, g⊥ = 2.028; A = –159.5 · 10–4 cm–1, A = –36.9 · 10–4 cm–1). The coordination geometry of the CuII guest complex in the tetrahedral Cu/Zn system is rather distorted, which is shown by the changed g and A Cu tensor parameters (g|| = 2.143, g⊥ = 2.042; A = –103.0 · 10–4 cm–1, A ≈ –5.0 · 10–4 cm–1). The spin density distribution is discussed using EHT molecular orbital calculations. 相似文献
43.
K. Schmalzl D. Wallacher M. M. Koza M. Rheinstädter D. Strauch K. Knorr 《The European physical journal. Special topics》2007,141(1):117-120
The role of geometrical confinement on the dynamics of
argon is studied. We have investigated 36Argon adsorbed
in nanoporous Gelsil glass by inelastic neutron scattering.
By fractional filling the `dimensionality' of the system is tuned
from a two-dimensional towards the bulk state. Ab-initio
calculations of plane sheets of Ar atoms and of bulk Ar are
compared to the experimental results. A shift of various phonon
modes to lower energies with decreasing dimensionality is observed
in the results of both methods. 相似文献
44.
Strauch S Berman BL Adams G Ambrozewicz P Anghinolfi M Asavapibhop B Asryan G Audit G Avakian H Bagdasaryan H Baillie N Ball JP Baltzell NA Barrow S Batourine V Battaglieri M Beard K Bedlinskiy I Bektasoglu M Bellis M Benmouna N Bennhold C Biselli AS Boiarinov S Bouchigny S Bradford R Branford D Briscoe WJ Brooks WK Bültmann S Burkert VD Butuceanu C Calarco JR Careccia SL Carman DS Carnahan B Chen S Cole PL Coleman A Coltharp P Cords D Corvisiero P Crabb D Crannell H Cummings JP Degtyarenko PV 《Physical review letters》2005,95(16):162003
45.
Strauch S von Neumann-Cosel P Rangacharyulu C Richter A Schrieder G Schweda K Wambach J 《Physical review letters》2000,85(14):2913-2916
The 48Ca(e,e(')n) reaction has been investigated for excitation energies 11-25 MeV and momentum transfers 0.22-0.43 fm(-1) at the superconducting Darmstadt electron linear accelerator S-DALINAC. Electric dipole and quadrupole plus monopole strength distributions are extracted from a multipole decomposition of the spectra. Their fragmented structure is described by microscopic calculations allowing for coupling of the basic particle-hole excitations to more complex configurations. Comparison of the excitation spectrum of the residual nucleus 47Ca with statistical model calculations reveals a 39(5)% contribution of direct decay to the damping of the giant dipole resonance. 相似文献
46.
47.
The recent microscopic model of Michel and Naudts for the interaction of ionic vibrational displacements and molecular rotational displacements is combined with the lattice dynamical shell model to calculate phonon dispersion curves of KCN and NaCN. Very good agreement with the existing experimental data is obtained. In particular, the upward dispersion of the TA phonon branches, characteristic of the alkali cyanide crystals, is well reproduced. 相似文献
48.
P. Kostyrko M. Macaj T. Salá t O. Strauch 《Proceedings of the American Mathematical Society》2001,129(9):2647-2654
The set of all statistical limit points of a given sequence is characterized as an -set. It is also characterized in terms of discontinuity points of distribution functions of .
49.
Quantum Zeno and anti-Zeno paradoxes 总被引:1,自引:0,他引:1
Continuous observation of a time independent projection operator is known to prevent change of state (the quantum Zeno paradox).
We discuss the recent result that generic continuous measurement of time dependent projection operators will in fact ensure
change of state: an anti-Zeno paradox. 相似文献
50.
Abstract In the hydrosphere sulfates of the following origin may exist: (1) evaporitic; they come from the leaching of sulfate rocks, (2) biological, formed by sulfur-oxidizing bacteria and (3) anthropogenic, which get into water with wastes, fertilizers or acid rains. Chemical analyses may reveal sulfates in water, but their origin cannot be assessed by means of chemical analysis. The sulfates of various origin may differ in their isotopic compositions. However, sometimes we can observe the similarity of δ34S of sulfates whose origin was entirely different. This similarity may be so suggestive that it could be misleading. This paper presents patterns of completely different sulfates whose δ34S are similar, though they have nothing in common. Other tables present patterns of sulfates whose origin is similar or even the same but their δ34S are characterized by great variety. All of the isotopic data presented in the tables were specially chosen from some of the results of the studies of the sulfates in waters in Poland. Isotopes techniques are becoming more popular and are useful for studies in many fields. These patterns may be a warning against drawing hasty conclusions from the results of δ-measuring. 相似文献