全文获取类型
收费全文 | 112篇 |
免费 | 3篇 |
专业分类
化学 | 51篇 |
晶体学 | 1篇 |
数学 | 7篇 |
物理学 | 56篇 |
出版年
2019年 | 4篇 |
2015年 | 3篇 |
2014年 | 2篇 |
2013年 | 3篇 |
2012年 | 5篇 |
2011年 | 5篇 |
2010年 | 4篇 |
2009年 | 4篇 |
2008年 | 4篇 |
2007年 | 8篇 |
2006年 | 7篇 |
2005年 | 4篇 |
2004年 | 2篇 |
2003年 | 5篇 |
2002年 | 4篇 |
2001年 | 1篇 |
2000年 | 2篇 |
1999年 | 3篇 |
1997年 | 1篇 |
1996年 | 2篇 |
1995年 | 2篇 |
1994年 | 1篇 |
1993年 | 3篇 |
1992年 | 1篇 |
1991年 | 2篇 |
1990年 | 2篇 |
1989年 | 3篇 |
1988年 | 4篇 |
1987年 | 1篇 |
1986年 | 4篇 |
1985年 | 1篇 |
1984年 | 4篇 |
1983年 | 2篇 |
1982年 | 2篇 |
1981年 | 2篇 |
1979年 | 1篇 |
1976年 | 2篇 |
1975年 | 2篇 |
1973年 | 1篇 |
1882年 | 2篇 |
排序方式: 共有115条查询结果,搜索用时 0 毫秒
21.
S. Brant K. Sistemich V. Paar G. Lhersonneau 《Zeitschrift für Physik A Hadrons and Nuclei》1988,330(4):365-369
Unique-parity states of97Y are studied in the framework of the interacting boson-fermion model (IBFM). Spin assignments for the levels of the unique-parity yrast band are proposed on the basis of nuclear systematics and the IBFM band pattern associated with coupling of a particle-type quasiparticle (g9/2) to the SU(5) core38 96Sr58. The good fit of the experimental data with the IBFM calculations confirms the single particle character of this immediate neighbour of the doubly sub-magic nucleus96Zr. 相似文献
22.
H. Seyfarth S. Brant P. Göttel V. Paar D. Vorkapić D. Vretenar 《Zeitschrift für Physik A Hadrons and Nuclei》1988,330(2):141-152
The results of aγ-γ angular correlation and a low energyγ-ray singles measurement using thermal neutron capture in39K are presented. The properties of low-lying levels of40K are interpreted in a comparison of the experimental data with the Interacting-Boson-Fermion-Fermion Model (IBFFM). The level fluctuation properties of the IBFFM spectrum are analysed and a sizeable deviation from chaoticity is found. 相似文献
23.
24.
G. Lhersonneau S. Brant H. Ohm V. Paar K. Sistemich D. Weiler 《Zeitschrift für Physik A Hadrons and Nuclei》1989,334(3):259-267
A level scheme has been established for 37 94 Rb57 based on studies at the fission-product separator JOSEF ofγγ coincidences following theβ- decay of94Kr. For the 190.7 keV level a half-life of 2.5(8) ns has been determined through the centroid-shift method. The majorβ-decay branch of94Kr proceeds with log ft=3.7 into the 988.4 keV state in94Rb. This transition must be of the 0+→1+ GT type involving the transitionνg7/2→πg9/2. IBFFM calculations have been performed for94Rb, starting from the parametrization used in the previous IBM investigations for the isotope93Rb and the isotone96Y. A theoretical interpretation of the low-lying levels including propositions for the spins is given in a comparison to the available data. 相似文献
25.
Aggregation and Deposition Characteristics of Fullerene Nanoparticles in Aqueous Systems 总被引:3,自引:0,他引:3
Jonathan Brant Hélène Lecoanet Mark R. Wiesner 《Journal of nanoparticle research》2005,7(4-5):545-553
The propensity of n-C60 to aggregate and deposit will play a key role in determining its longevity in aquatic systems, and therefore the potential exposure and risk presented by these colloids. We consider the origin of n-C60 stability and compare the aggregation and deposition characteristics of n-C60 under conditions of variable ionic strength using an indifferent electrolyte. Relatively weak electrolyte solutions (0.001 M) were observed to destabilize suspensions of n-C60 resulting in the formation of settleable aggregates. This behavior supports the hypothesis that the stabilizing mechanism for n-C60 clusters is electrostatic in origin. Similarly, the deposition of n-C60 in porous media increased as ionic strength increased. These observations suggest that under some conditions present in natural aquatic systems, these materials may have limited mobility as they form large aggregates that may settle out of suspension or deposit on surfaces. These phenomena may, at least partially, offset any risk presented by n-C60 toxicity due to a reduced potential for exposure. 相似文献
26.
This article reviews our recent results on the steam reforming of methanol over a series of NiAl-layered double hydroxide
catalysts prepared by the co-precipitation method. The influence of calcination temperature, reaction temperature, pretreatment
temperature and atmospheres, inorganic salt ions and steam to methanol ratio on the catalytic performance was studied. The
major products for many of the catalysts were H2, CO, CO2 and CH4. However, the product composition varies significantly with the experimental parameters and high selectivity for CO2 and H2 was observed under various conditions, showing the potential of Ni based catalysts for the production of highly pure hydrogen. 相似文献
27.
Brant C. Jones 《Order》2009,26(4):319-330
We give an explicit nonrecursive complete matching for the Hasse diagram of the strong Bruhat order of any interval in any Coxeter group. This yields a new derivation of the Möbius function, recovering a classical result due to Verma. 相似文献
28.
The crystal structure of the defect perovskite series Sr1−xTi1−2xNb2xO3 has been investigated over a range of temperatures using high-resolution synchrotron X-ray diffraction, neutron diffraction and electron diffraction. Three distinct regions were observed: 0<x≤0.125 was a solid solution of Sr1−xTi1−2xNb2xO3 with minor SrTiO3 intergrowth, 0.125<x≤0.2 was a pure Sr1−xTi1−2xNb2xO3 solid solution adopting the cubic perovskite type structure (Pm3¯m) and for x>0.2 Sr0.8Ti0.6Nb0.4O3 and Sr3TiNb4O15 formed a two phase region. The cubic structure for Sr0.8Ti0.6Nb0.4O3 was stable over the temperature range 90-1248 K and the thermal expansion co-efficient was determined to be 8.72(9)×10−6 K−1. Electron diffraction studies revealed diffuse scattering due to local scale Ti/Nb displacements and slightly enhanced octahedral rotations that did not lead to long range order. The octahedral rotations were observed to ‘lock-in’ at temperatures below ∼75 K resulting in a tetragonal structure (I4/mcm) with anti-phase octahedral tilting about the c-axis. 相似文献
29.
In the Interacting Boson-Fermion-Fermion Model (IBFFM) for odd-odd nuclei the yrast states are calculated for \(\tilde j_\pi = \tilde h_{1 1/2} ,\tilde j_v = \tilde i_{1 3/2} \) , proton-neutron configurations coupled to theO(6) andSU(3) boson core. The results are discussed in terms of the strongly coupled/ decoupled band type criterion and in comparison to the peaceful and conflicting case of asymmetric rotor model. 相似文献
30.
Laura Bradford Meredith Harris Brant Jones Alex Komarinski Carly Matson Edwin O’Shea 《The Ramanujan Journal》2014,34(2):163-176
Bousquet-Mélou & Eriksson’s lecture hall theorem generalizes Euler’s celebrated distinct-odd partition theorem. We present an elementary and transparent proof of a refined version of the lecture hall theorem using a simple bijection involving abacus diagrams. 相似文献