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91.
A total coloring of a graph G is a coloring of all elements of G, i.e. vertices and edges, such that no two adjacent or incident elements receive the same color. A graph G is s-degenerate for a positive integer s if G can be reduced to a trivial graph by successive removal of vertices with degree ≤s. We prove that an s-degenerate graph G has a total coloring with Δ+1 colors if the maximum degree Δ of G is sufficiently large, say Δ≥4s+3. Our proof yields an efficient algorithm to find such a total coloring. We also give a lineartime algorithm to find a total
coloring of a graph G with the minimum number of colors if G is a partial k-tree, that is, the tree-width of G is bounded by a fixed integer k. 相似文献
92.
Y. Funaki A. Tohsaki H. Horiuchi P. Schuck G. Röpke 《The European Physical Journal A - Hadrons and Nuclei》2006,28(3):259-263
In order to discuss the spatial extention of the 02
+-state of 12C (Hoyle state), we analyze the inelastic form factor of electron scattering to the Hoyle state, which our 3α-condensate wave
function reproduces very well like previous 3α RGM/GCM models. The analysis is made by varying the size of the Hoyle state
artificially. As a result, we find that only the maximum value of the form factor sensitively depends on its size, while the
positions of maximum and minimum are almost unchanged. This size dependence is found to come from a characteristic feature
of the transition density from the ground state to the Hoyle state. We further show the theoretical predictions of the inelastic
form factor to the 22
+-state of 12C, which was recently observed above the Hoyle state, and of the inelastic form factor to the calculated 03
+-state of 16O, which was conjectured to correspond to the 4α condensed state in previous theoretical work by the present authors. 相似文献
93.
94.
95.
Hisao Yamashige Shuji Matsuo Tsutomu Kurisaki Rupert C C Perera Hisanobu Wakita 《Analytical sciences》2005,21(3):309-314
X-ray absorption near edge structure (XANES) measurements at the C, N, and Fe K absorption edges were performed for iron(III)-tetraphenylporphyrin (FeTPP), iron(III)-tetrakis(p-carboxyphenyl)porphyrin (FeTCPP), and iron(III)-tetrakis(p-sulfonatophenyl)porphyrin (FeTSPP). The spectral shapes differ in the Fe K XANES, but not in C and N K XANES among FeTPP, FeTCPP, and FeTSPP. Crosschecks of XANES data for C, N, and Fe K absorption edges in combination with discrete variational (DV)-Xalpha molecular orbital (MO) calculations indicate that each p-electron-withdrawing group on four meso-phenyl substitutes in an Fe(III)-porphyrin complex brings about a unique electron state through the complex because of the electron-withdrawal strength, itself. Consequently, they affect the positive charge of the center Fe(III) ion. 相似文献
96.
Tomohisa Yamashita Shuji Kodama Mikiya Ohto Eriko Nakayama Sumiyo Hasegawa Nobutaka Takayanagi Tomoko Kemmei Akira Yamaguchi Norio Teramae Yukio Saito 《Analytical sciences》2006,22(12):1495-1500
The permeation fluxes of phenol, benzene sulfonate (BS) and benzene disulfonate (BDS) through a porous anodic alumina membrane with the perpendicularly oriented silica-surfactant nanochannel assembly membrane (NAM) were measured in water-ethanol mixture media. The permeation flux depended on solute charges and on solvent composition. As the ethanol ratio increased, the fluxes of BS and BDS increased and the flux of phenol decreased. The results of extraction/elution experiments also depended on the solute charges and the solvent composition. Chromatographic experiments in n-hexane showed that dipole and hydrophobic interactions affect the retention of solutes. Permeation of the solute across the NAM in water-ethanol mixture is likely to be determined by various factors such as dipole interaction, hydrophobic interaction, solvation, and anion-exchange efficiencies. 相似文献
97.
Hisao Yamashige Shuji Matsuo Tsutomu Kurisaki Rupert C C Perera Hisanobu Wakita 《Analytical sciences》2005,21(6):635-639
This study investigated the protonation of nitrogen atoms in porphyrins with meso-phenyl p-substituted by an electron-withdrawing group using N 1s X-ray photoelectron spectroscopy (XPS), the N K X-ray absorption near-edge structure (XANES), and the discrete variational (DV)-Xalpha molecular orbital (MO) method. Both tetraphenylporphyrin (TPP) and tetrakis(p-sulfonatophenyl)porphyrin (TSPP) have a single structure: the former has two protonated and two non-protonated N atoms in the porphine ring; the latter has four protonated N atoms in the porphine ring. In contrast, a combination of XPS, XANES, and DV-Xalpha MO calculations shows that tetrakis(p-carboxyphenyl)porphyrin (TCPP) has a dual structure: one structure has two protonated and two non-protonated N atoms; the other has four protonated N atoms. Furthermore, this result was also considered based on the protonation constants of N atoms in the porphyrins. The correlation between the strength of electron-withdrawing groups and protonation to N atoms in porphyrins can be described using the spectral patterns of the N 1s XPS and N K XANES spectra. 相似文献
98.
Funaki Y. Tohsaki A. Horiuchi H. Schuck P. Röpke G. 《The European Physical Journal A - Hadrons and Nuclei》2005,24(3):321-342
The states with Jπ = 0+, 2+, and 4+ of 12C with excitation energies less than about 15 MeV are investigated with the alpha condensate wave function with spatial deformation and by using the method of ACCC (analytic continuation in the coupling constant) which is necessary for a proper treatment of resonance states. The calculated energy and width of the recently observed 22+ state are found to be well reproduced. The obtained 22+ wave function has a large overlap with a single condensate wave function of 3α gas-like structure. The density distribution is shown to be almost the same as that of the 02+ state that is regarded as a 3α Bose-condensed state, if the energy of the 22+ state is scaled down to the same value as the one of the 02+ state. Furthermore, the kinetic energy, nuclear interaction energy, and Coulomb interaction energy of the calculated 22+ state are shown to be very similar to those of the 02+ state. We conclude that the 22+ state has a structure similar to the 02+ state of Bose-condensate character with a dilute 3α gas-like structure. In addition, the resonance states, 03+, 04+, 42+, are also discussed. 相似文献
99.
Koji Ishida Yoshiaki Uchida Shuji Ninomiya Masumi Osawa 《Fresenius' Journal of Analytical Chemistry》1990,336(5):419-422
Summary The thin-layer chromatographic behaviour of all the rare earths except Pm on silica gel in aqueous solutions of five alkali metal chlorides has been surveyed. The Rf-values and the logarithms of the separation factors relative to Gd vary in a regular and peculiar way with increasing atomic number, through a reflection of the strong tetrad effect. A discussion concerning the effects on the Rf-values of the solvent cations and the solvent anions, and typical chromatograms for the separations of multi-component mixtures containing adjacent lanthanoids are also presented. 相似文献
100.
Xiao Tong Satoru Ohuchi Takehiro Tanikawa Ayumi Harasawa Taichi Okuda Yoshinobu Aoyagi Toyohiko Kinoshita Shuji Hasegawa 《Applied Surface Science》2002,190(1-4)
The evolution of Si 2p core-level photoemission during a structural conversion from the Si (1 1 1)–
-Ag to the Si(1 1 1)–
-Ag superstructures induced by Ag adatoms adsorption at 140 K was studied using synchrotron radiation. The component from the top-layer Si-trimer atoms on the former surface was found to split into two components in the latter surface. The result is discussed in terms of a relaxation in some of the Si trimers induced by Ag adatoms sitting on the nearby Ag triangles of the
-Ag substrate. The intensity ratio between the split components is a key to exclude some structure models proposed so far for the
phases. 相似文献