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141.
142.
Marc Levine 《K-Theory》1992,6(2):113-175
LetR be a commutative, semi-local ring,I
1, ...,I
s
ideals. In this paper, we define therelative Milnor K-groups of (R;I
1, ...,I
s
),K
p
M
(R;I
1, ...,I
s
), and show that these groups have many of the properties of the usual MilnorK-groups of a field. In particular, assuming a weak condition on the ideals, we show thatK
p
M
(R;I
1, ...,I
s
) is isomorphic to the weightp portion of the relative QuillenK-groupK
p
(R;I
1, ...,I
s
), after inverting (p–1)!. We also define the relative group homology of GL
n
(R;I
1, ...,I
s
), and show thatK
p
M
(R;I
1, ...,I
s
) is isomorphic toH
p
(GLp(R;I
1, ...,I
s
))/Im(H
p
(GL
p–1 (R;I
1, ...,I
s
))). Finally, we consider a generalization to the relative setting of Kato's conjecture asserting that the Galois symbol gives an isomorphism fromK
p
M
(F)/l
v
to
, and show that this relative version of Kato's conjecture implies the Quillen-Lichtenbaum conjectures asserting the Chern class:
相似文献
143.
The Hodge Filtration and Cyclic Homology 总被引:1,自引:0,他引:1
Charles Weibel 《K-Theory》1997,12(2):145-164
We relate the Hodge filtration of the cohomology of a complex algebraic variety X to the Hodge decomposition of its cyclic homology. If X is smooth and projective,
is the quotient of the Betti cohomology
by the
piece of the Hodge filtration. 相似文献
144.
Yoshishige Haraoka 《Transactions of the American Mathematical Society》1997,349(2):675-712
The hypergeometric function of general type, which is a generalization of the classical confluent hypergeometric functions, admits an integral representation derived from a character of a linear abelian group. For the hypergeometric function on the space of matrices, a basis of cycles for the integral is constructed by a limit process, which is called a process of confluence. The determinant of the period matrix is explicitly evaluated to show the independence of the cycles.
145.
A new method is described for generating all-atom protein structures from C-atom information. The method, which combines both local structural trace alignments and comparative side chain modeling with ab initio side chain modeling, makes use of both the virtual-bond and the dipole-path methods. Provided that 3D structures of structurally and functionally related proteins exist, the method presented here is highly suitable for generating all-atom coordinates of partly solved, low-resolution crystal structures. Particularly the active site region can be modeled accurately with this procedure, which enables investigation of the binding modes of different classes of ligands with molecular dynamics simulations. The method is applied to the trace of Streptococcus pneumoniae, in order to construct an all-atom structure of the transpeptidase domain. Since after generation of full coordinates of the transpeptidase domain the structure had been solved to 2.4 Å resolution, new X-ray coordinates for the worst modeled loop (residues T370 to M386; 17 out of a total number of 351 residues constituting the transpeptidase domain) were incorporated, as kindly provided by Dr. Dideberg. The structure was relaxed with molecular dynamics simulations and simulated annealing methods. The RMS deviation between the 144 aligned C-atoms and the corresponding ones in the originally solved 3.5 Å resolution crystal structure was 0.98. The 351 C-atoms of the whole transpeptidase domain of the final model showed an RMS deviation of 1.58. The Ramachandran plot showed that 79.3% of the residues are in the most favored regions, with only 1.0% occurring in disallowed regions. The model presented here can be used to investigate the three-dimensional influences of mutations around the active site of PBP2x. 相似文献
146.
Humberto Carrillo Calvet 《Applicable analysis》2013,92(3-4):191-208
The theorems that are presented in this paper, are a contribution to the foundations of the averaging method for ordinary differential equations. They involve the study of the persistent features of vector fields, under non autonomous perturbations of mean value zero. The problem of obtain ing qualitative information from the study of the averaged equation is considered and theorems that give new conditions to guarantee the uniform validitv of the approximation over the time interval [ 0.∞), are proved. A general icsult on the persistence of attractors is presented. The analysis uses in a fundamental way, a generalization of the notion of a solution stable under persistent disturbances. The proofs do not require special behavior of the linearized system and the results obtained are not only local, but give relevant information about the persistence of domains of attraction. 相似文献
147.
One of the major challenges for protein tertiary structure prediction strategies is the quality of conformational sampling algorithms, which can effectively and readily search the protein fold space to generate near‐native conformations. In an effort to advance the field by making the best use of available homology as well as fold recognition approaches along with ab initio folding methods, we have developed Bhageerath‐H Strgen, a homology/ab initio hybrid algorithm for protein conformational sampling. The methodology is tested on the benchmark CASP9 dataset of 116 targets. In 93% of the cases, a structure with TM‐score ≥ 0.5 is generated in the pool of decoys. Further, the performance of Bhageerath‐H Strgen was seen to be efficient in comparison with different decoy generation methods. The algorithm is web enabled as Bhageerath‐H Strgen web tool which is made freely accessible for protein decoy generation ( http://www.scfbio‐iitd.res.in/software/Bhageerath‐HStrgen1.jsp ). © 2013 Wiley Periodicals, Inc. 相似文献
148.
Li Shirong 《代数通讯》2013,41(6):1913-1918
In this paper, the minimal subgroups of a finite group G are studied. Using the normalizes of Sylow subgroups of G, we obtain some sufficient conditions for G to be p-milpotent and supersolvable, which ae extensions of the related results of Burnside, Ito, Buckley and Asaad. 相似文献
149.
M. Kawano A. Ramesh V. D. Thao R. Tatsukawa A. N. Subramanian 《International journal of environmental analytical chemistry》2013,93(3-4):163-174
Abstract A wide variety of agricultural soils from different regions of India such as paddy, wheat, mustard, potato, cotton, tea, tomato, sugarcane, grape and urban soils were surveyed for the residual levels of persistent organochlorine insecticide residues in 1988 and 1989. DDT and HCH concentrations were found to be higher in upland soils and lower in paddy field soils. These results indicate the large application of HCH and DDT compounds for agricultural purposes in India. In urban soil DDT levels were higher than HCHs reflecting the use of the former insecticide in relatively large amounts for vector control. Among DDT compounds, p,p′-DDE showed higher percentage in paddy and upland soils. On the other hand, p,p′-DDT contributed to higher levels in urban soils. The β-HCH was detected as the dominant isomer in both agricultural and non agricultural soils. The levels and percentage compositions of DDTs and HCHs revealed the extent of environmental contamination caused by the continuous usage of persistent organochlorine insecticides in large quantities in tropical areas like India. 相似文献
150.
Covalent networks formed by on-surface synthesis usually suffer from the presence of a large number of defects. We report on a methodology to characterize such two-dimensional networks from their experimental images obtained by scanning probe microscopy. The computation is based on a persistent homology approach and provides a quantitative score indicative of the network homogeneity. We compare our scoring method with results previously obtained using minimal spanning tree analyses and we apply it to some molecular systems appearing in the existing literature. 相似文献
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