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The structure of nuclear transition matrix elements (NTMEs) required for the study of neutrinoless double-β decay within light Majorana neutrino mass mechanism is disassembled in the PHFB model. The NTMEs are calculated using a set
of HFB intrinsic wave functions, the reliability of which has been previously established by obtaining an overall agreement
between the theoretically calculated spectroscopic properties and the available experimental data. Presently, we study the
role of short-range correlations, radial evolution of NTMEs and deformation effects due to quadrupolar correlations. In addition,
limits on effective light neutrino mass 〈m
ν
〉 are extracted from the observed limits on half-lives T
12/0ν
of neutrinoless double-β decay. 相似文献
24.
2-(o-Hydroxyphenyl)-1,8-naphthyridine (HN), 2-(4-hydroxy-6-methylpyran-2-one-3-yl)-1,8-naphthyridine (HMPN) and 2-(benzimidazol-2-yl)-1,8-naphthyridine(BN) react with acetates of Mn(II), Co(II), Ni(II), Cu(II) and Zn(II) to yield metal ion complexes of definite composition. These compounds were characterized by elemental analyses, molar conductivity, magnetic susceptibility measurements, thermal studies, IR, UV-visible, NMR and mass spectral investigations. The complexes are found to have the formulae [M(HN)2(H2O)2], [M(HMPN)2(H2O)2] and [M(BN)2(OAc)2], respectively. 相似文献
25.
Jyothi Rajesh Kumar Joon-Soo Kim Jin-Young Lee Ho-Sung Yoon 《Journal of Radioanalytical and Nuclear Chemistry》2010,285(2):301-308
The present scientific study on uranium(VI) solvent extraction and vanadium(V) separation from sulfate solutions using Alamine
336 as an extractant diluted in kerosene was established. The preliminary experiments indicating the uranium extraction process
will follow the solvation as well as ion-exchange mechanisms. In the present acid region (0.1–1.0 mol dm−3 H2SO4) it showing the ion-exchange type mechanism. Time (1–120 min) and temperature (25–55 °C) not influencing the present extraction
system. Other experimental parameters like loading capacity of Alamine 336, stripping of uranium from loaded organic phase,
recycling of Alamine 336 and separation of uranium(VI)/vanadium(V) was studied. 相似文献
26.
Solvent extraction behaviour of lanthanum(III), cerium(III), europium(III), thorium(IV) and uranium(VI) with 3-phenyl-4-benzoyl-5-isoxazolone 总被引:1,自引:0,他引:1
The extraction behaviour of La(III), Ce(III), Eu(III), Th(IV) and U(VI) with 3-phenyl-4- benzoyl-5-isoxazolone (HPBI) in chloroform has been studied. The mechanism of extraction and the species extracted have been identified. Extraction constants for each system have been calculated. The system has been used to separate Th(IV) from U(VI) and from La(III), Ce(III) and Eu(III). A comparison of the extraction constants with those for the 1-phenyl-3-methyl-4-benzoyl-5-pyrazolone (HPMBP) and thenoyltrifluoroacetone (HTTA) systems indicates that HPBI extracts these metal species better than HPMBP and HTTA do. 相似文献
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28.
Bertram R Asbury T Fabiola F Quine JR Cross TA Chapman MS 《Journal of magnetic resonance (San Diego, Calif. : 1997)》2003,163(2):300-309
The orientation data provided by solid-state NMR can provide a great deal of structural information about membrane proteins. The quality of the information provided is, however, somewhat degraded by sign degeneracies in measurements of the dipolar coupling tensor. This is reflected in the dipolar coupling penalty function used in atomic refinement, which is less capable of properly restraining atoms when dipolar sign degeneracies are present. In this report we generate simulated solid-state NMR data using a variety of procedures, including back-calculation from crystal structures of alpha-helical and beta-sheet membrane proteins. We demonstrate that a large fraction of the dipolar sign degeneracies are resolved if anisotropic dipolar coupling measurements are correlated with anisotropic chemical shift measurements, and that all sign degeneracies can be resolved if three data types are correlated. The advantages of correlating data are demonstrated with atomic refinement of two test membrane proteins. When refinement is performed using correlated dipolar couplings and chemical shifts, perturbed structures converge to conformations with a larger fraction of correct dipolar signs than when data are uncorrelated. In addition, the final structures are closer to the original unperturbed structures when correlated data are used in the refinement. Thus, refinement with correlated data leads to improved atomic structures. The software used to correlate dipolar coupling and chemical shift data and to set up energy functions and their derivatives for refinement, CNS-SS02, is available at our web site. 相似文献
29.
Quantum mechanical calculations at all valence complete neglect of differential overlap (CNDO/2) and self-consistent charge
extend Huckel (SCC-EH) and the Pi electron Pariser-Parr-Pople with limited configuration interaction (PPP-LCI) levels of approximation
have been accomplished for monothiobiuret and dithiobiuret. From the calculated results, a discussion of the electronic structure,
photoelectron and electronic spectra and the conformational stability are given. The electronic and1H nmr spectra are also reported. A trans-cis-CONHCS-structure is found to be the stable conformation for monothiobiuret consistent
with other evidences. 相似文献
30.
The geometric theory of partial differential equations due to E. Cartan is applied to atomic systems in order to solve the many-body problems and to obtain the binding energies of electrons in an atom. The procedure consists in defining a Schrödinger equation over an Euclidean patch which overlaps with other Euclidean patches in a specified way to form a manifold. If the energy of the system has to be a minimum, it is shown using the Dirichlet principle that the coordinate systems are related by the Cauchy-Riemann relations. The invariance of the Schrödinger equations in the overlapping region leads to a nonlinear second-order equation which is invariant to automorphic transformations and whose solutions are doubly periodic functions. There are only two possible single-valued solutions to this nonlinear partial differential equation and these correspond to lattices of points in the complex space, which are (a) corners of an array of equilateral triangles, and (b) corners of an array of isosceles right-angled triangles. The first solution was used in an earlier work to derive many static properties of nuclei. In this paper it is shown that the second solution gives binding energies of atoms in agreement of about 3% for the few experimental points that are available and also in good agreement with the binding energies of atoms obtained by the perturbation theory. It is also shown that this lattice under certain approximations is equivalent to a pure Coulomb law and the Bohr orbits of the hydrogen atom are correctly predicted. In obtaining the binding energies of atoms, no free parameters are required in the theory, except for the value of the binding energy of the He atom, as the theory is developed only for spinless systems. All other constants turn out to be fundamental constants. 相似文献