全文获取类型
收费全文 | 58篇 |
免费 | 2篇 |
国内免费 | 4篇 |
专业分类
化学 | 29篇 |
晶体学 | 2篇 |
力学 | 1篇 |
数学 | 1篇 |
物理学 | 31篇 |
出版年
2015年 | 1篇 |
2014年 | 1篇 |
2013年 | 5篇 |
2011年 | 4篇 |
2010年 | 3篇 |
2009年 | 5篇 |
2008年 | 5篇 |
2007年 | 4篇 |
2006年 | 2篇 |
2005年 | 2篇 |
2003年 | 1篇 |
2002年 | 1篇 |
2000年 | 2篇 |
1999年 | 2篇 |
1998年 | 3篇 |
1997年 | 1篇 |
1996年 | 1篇 |
1995年 | 2篇 |
1994年 | 2篇 |
1993年 | 1篇 |
1992年 | 1篇 |
1991年 | 1篇 |
1989年 | 1篇 |
1988年 | 1篇 |
1986年 | 3篇 |
1985年 | 1篇 |
1984年 | 1篇 |
1979年 | 1篇 |
1978年 | 2篇 |
1977年 | 1篇 |
1976年 | 2篇 |
1939年 | 1篇 |
排序方式: 共有64条查询结果,搜索用时 15 毫秒
1.
P.A. Fantin P.L. Barbieri A. Canal Neto F.E. Jorge 《Journal of Molecular Structure》2007,810(1-3):103-111
2.
Avenoza A Busto JH Canal N Peregrina JM 《Chemical communications (Cambridge, England)》2003,(12):1376-1377
The reactivity of 2-acylaminoacrylates with ketene diethyl acetal can be modulated by means of thermal conditions to yield cyclobutanes for the preparation of protected beta-hydroxycyclobutane-alpha-amino acids, or catalytic conditions that yield cyclohexanes by tandem condensations to obtain interesting building blocks that are alternatives to Danishefsky's diene. 相似文献
3.
C. M. Arizmendi A. H. Rizzo L. N. Epele C. A. García Canal 《Zeitschrift für Physik B Condensed Matter》1991,83(2):273-276
The Hamiltonian limit of the ANNNI model in (1+1) dimensions is studied by using the Quantum Statistical Monte Carlo method. Even if recent results suggest that Monte Carlo calculations may prove unreliable in the study of this system, the phase diagram of the quantum version of the model was successfully obtained. In particular, the clusive transitions between the disordered, the floating incommensurate and the degenerate 2, 2 are determined by analysing the correlation length behaviour in finite lattices.Partially supported by CONICET Argentina 相似文献
4.
The well-known Hellmann-Feynman theorem of quantum mechanics connected with the derivative of the eigenvalues with respect to a parameter upon which the Hamiltonian depends, is generalized to include cases in which the domain of definition of the Hamiltonian of the system also depends on that parameter. 相似文献
5.
Mudasir Ahmad Tantry Reehana Khan Seema Akbar Abdul Rouf Dar Abdul Sami Shawl Mohammad Sarwar Alam 《中国化学快报》2011,22(5):575-579
An unusual oleanane triterpene(1) was isolated from aerial parts of Rhododendron campanulatum.The compound had shown prominent antibacterial and immunomodulatory activities.The structure of the compound was determined by spectroscopic data including 1D and 2D NMR spectral analysis. 相似文献
6.
An alternative theoretical analysis directed to obtaining a more accurate expression for the critical power in the symmetric nonlinear directional coupler, or other nonlinear, five-layer waveguiding structures, is reported. Our analysis works with the nonlinear supermodes of the waveguide, and it is presented as an improvement of the preceding study by Silberberg and Stegeman [1]. Numerical simulations comparing both techniques, and by means of the beam propagation method, are reported for a few cases. A set of three representative, power dependent parameters is proposed, in order to give a comprehensive view of the power flow between both branches in the device as a function of the excitation conditions. 相似文献
7.
Alejandro Pati?o Cristina Canal Cristina Rodríguez Gabriel Caballero Antonio Navarro José Ma Canal 《Cellulose (London, England)》2011,18(4):1073-1083
The surface of cotton fabrics was functionalized through corona plasma treatments and/or by cationising the whole of the fibre
with an epihalohydrin. The effects of both treatments, individually and in combination are analyzed through wettability studies,
by X-ray photoelectron spectroscopy (XPS), Scanning electron microscopy (SEM), and also by dyeing studies with an hetero bis
functional reactive dye. Plasma improved wetting properties, exhaustion of the dyebaths and K/Scorr of the fabrics through surface functionalisation. Cationising of the cotton highly increased the exhaustion of the dyebaths
and produced a dramatic improvement in K/Scorr. Plasma treatment previous to cationising increased the impregnation of the fabrics, but the effects of both treatments on
dyeing parameters are additive only in column water rise and generally the effects obtained by cationising with the epihalohydrin
prevail. The differences between both treatments are discussed in terms of surface functionalisation of the cotton fibres. 相似文献
8.
A contracted basis set of triple zeta (TZ) valence quality for the atoms from K to Kr was constructed from fully-optimized Gaussian basis sets generated in this work. Gaussian polarization functions (d, f, and g symmetries), which were optimized at the second-order Mφller–Plesset level, were added to the TZ set. This extends earlier work on segmented contracted TZ basis set for atoms H-Ar. This set along with the BP86 non-hybrid and B3LYP hybrid functionals were used to calculate geometric parameters, dissociation energy, harmonic vibrational frequency, and electric dipole moment of a sample of molecules and, then, comparison with results obtained with other basis sets and with experimental data reported in the literature is done. CCSD(T) atomic excitation energies and bond lengths, dissociation energies, and harmonic vibrational frequencies of some diatomics were also evaluated. Using density functional theory and gauge-including atomic orbitals, 57Fe and 77Se nuclear magnetic resonance chemical shifts in Fe(C5H5)2, H2Se, (CH3)SeH, CSe2, SeCO, H2CSe, and SeF6 were calculated. Comparison with theoretical and experimental values previously published in the literature was done. It is verified that in general these results give good agreement with experimental and benchmark values. 相似文献
9.
J. Hernández F. Canal F. Dios L. Gastón 《International Journal of Infrared and Millimeter Waves》1988,9(3):295-301
Multilayer structures are of great interest in the fabrication of single mode devices for Integrated Optics. this work it is shown that a multilayer structure allows not only single-mode behaviour but it enhaces the non-reci procity of the quide. 相似文献
10.
Canal JP Jennings M Yap GP Pomeroy RK 《Dalton transactions (Cambridge, England : 2003)》2008,(10):1375-1382
A synthetic route to [Os4(mu-H)(mu-OH)(mu-CO)(CO)12] ( 1) has been devised through the activation of [Os4(CO)14] with Me3NO. The pyrolysis and photolysis of the reactant in the presence of a trace amount of water produces 1 in low yield. The solid-state structure of [Os4(mu-H)(mu-OH)(mu-CO)(CO)12 x H2O] (1 x H2O) reveals a butterfly Os4 skeleton with bridging H, OH and CO ligands as well as hydrogen-bonded molecules of water in the crystal lattice. A low-temperature 13C{1H} NMR spectroscopic study revealed a merry-go-round exchange of CO ligands around the Os3 plane containing the asymmetric bridging CO. The exposure of 1 x H2O to D2O yielded [Os4(mu-H)(mu-OD)(mu-CO)(CO)12]2. Although the solid-state, intramolecular structure of 2 closely matched that of 1 x H2O, the intermolecular structure did not: its crystal lattice contained no water of crystallization, a previously unreported crystallographic isotope effect. 相似文献