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231.
Anglin EJ Salisbury C Bailey S Hor M Macardle P Fenech M Thissen H Voelcker NH 《Lab on a chip》2010,10(24):3413-3421
We report on surface-engineered microarrays that provide in situ cell sorting, localization, and immobilization of various subsets of human primary lymphocytes, followed by an on-chip bioassay for ionizing-radiation-induced cytogenetic damage. The microarray format eliminates the necessity of separating cell sub-populations by alternative means (such as fluorescence- or magnetic-activated cell sorting) prior to performing informational bioassays. To exemplify the potential of this on-chip cytometry approach, we have integrated the cytokinesis-block micronucleus cytome (CBMNcyt) assay with the microarray platform for analysis of the chromosome damage profile of specific subsets of human peripheral lymphocytes. Microarray results were compared with data obtained from the traditional CBMNcyt assay on heterogeneous lymphocyte populations, and with flow cytometry data. Our results suggest that cytogenetic damage caused by ionizing radiation is not uniformly distributed across all lymphocytes subsets, but rather concentrated in specific subsets. The salient features of our approach are that it requires very small volumes of reagents, allows sorting of lymphocyte subsets in situ, increases parallelism of cell assays and is amenable to high content microscopy analysis. The on-chip cytometry format opens new vistas for advanced cell-based assays, potentially bringing to light important information which remains hidden with conventional assays and hence engendering new discoveries in cell biology. 相似文献
232.
233.
Gomila A Le Poul N Cosquer N Kerbaol JM Noël JM Reddy MT Jabin I Reinaud O Conan F Le Mest Y 《Dalton transactions (Cambridge, England : 2003)》2010,39(48):11516-11518
We report the self-induced "electroclick" immobilization of the [Cu(II)(6-ethynyl-TMPA)(H(2)O)](2+) complex, by its simple electro-reduction, onto a mixed azidoundodecane-/decane-thiol modified gold electrode. The redox response of the grafted [Cu(II/I)(TMPA)] at the modified electrode is fully reversible indicating no Cu coordination change and a fast electron transfer. 相似文献
234.
The synthesis and crystal structure of the novel reduced molybdenum oxide Mg4.5Pr79.5Mo126O312 are presented. This compound crystallizes in the trigonal space group R-3 m with a = 11.3061(2) Å, c = 58.242(1) Å, V = 6447.5(2) Å3, and Z = 1. Refinements yield R(F 2) = 0.0433 and wR(F 2) = 0.0931 for 2827 unique reflections. The structure is built up from alternating slabs made up of molybdenum forming Mo3, Mo7 and Mo19 clusters, praseodymium and oxygen atoms, and slabs containing isolated MoO6 octahedra. The Pr3+ cations are localized either within the slabs or at their borderlines to ensure the cohesion between the slabs. Of the six crystallographically independent sites occupy by the Pr3+ cations, two of them also contain randomly about 15% and 20% of Mg2+ cations while the remaining four are fully occupied by the Pr3+ cations. 相似文献
235.
Murielle Rivenet Nicolas Vigier Pascal Roussel Francis Abraham 《Journal of solid state chemistry》2009,182(4):905-912
The new U(VI) compound, [Ni(H2O)4]3[U(OH,H2O)(UO2)8O12(OH)3], was synthesized by mild hydrothermal reaction of uranyl and nickel nitrates. The crystal-structure was solved in the P-1 space group, a=8.627(2), b=10.566(2), c=12.091(4) Å and α=110.59(1), β=102.96(2), γ=105.50(1)°, R=0.0539 and wR=0.0464 from 3441 unique observed reflections and 151 parameters. The structure of the title compound is built from sheets of uranium polyhedra closely related to that in β-U3O8. Within the sheets [(UO2)(OH)O4] pentagonal bipyramids share equatorial edges to form chains, which are cross-linked by [(UO2)O4] and [UO4(H2O)(OH)] square bipyramids and through hydroxyl groups shared between [(UO2)(OH)O4] pentagonal bipyramids. The sheets are pillared by sharing the apical oxygen atoms of the [(UO2)(OH)O4] pentagonal bipyramids with the oxygen atoms of [NiO2(H2O)4] octahedral units. That builds a three-dimensional framework with water molecules pointing towards the channels. On heating [Ni(H2O)4]3[U(OH,H2O)(UO2)8O12(OH)3] decomposes into NiU3O10. 相似文献
236.
237.
Michel Keddam Dr. Nicolas Portail Dr. Dao Trinh Vincent Vivier Dr. 《Chemphyschem》2009,10(18):3175-3182
Scanning electrochemical microscopy (SECM) is a powerful technique for performing quantitative measurements at a local scale. This paper covers the development of combinations of SECM with electrochemical impedance spectroscopy (EIS) and electrochemical quartz crystal microbalance (EQCM). Basic aspects are described and potential applications reported by several research groups are covered. The unique advantages of the coupled techniques—with additional information being obtained from each coupling—are also discussed. 相似文献
238.
Corentin Boilleau Nicolas Suaud Roland Bastardis Nathalie Guihéry Jean Paul Malrieu 《Theoretical chemistry accounts》2010,126(3-4):231-241
DFT calculations are performed on a model mixed-valence system presenting a double exchange phenomenon. Due to the intrinsic multireference character of the lowest Ms components of the spin states, it is shown that the interactions involved in the double-exchange model cannot be simply extracted from the DFT energies as it is sometimes done. It is, however, possible to extract from different DFT single determinant energies the interactions of a generalized Hubbard Hamiltonian, from which, in a second step, the double-exchange spectrum may be evaluated. The problems generated by the charge and spin polarization are discussed in both symmetric and non symmetric geometries, and the sensitivity of the results to the choice of the density functional is illustrated. 相似文献
239.
Cationic (arene)ruthenium‐based tetranuclear complexes of the general formula [Ru4(η6‐p‐cymene)4(μ‐N∩N)2(μ‐OO∩OO)2]4+ were obtained from the dinuclear (arene)ruthenium complexes [Ru2(η6‐p‐cymene)2(μ‐OO∩OO)2Cl2] (p‐cymene=1‐methyl‐4‐(1‐methylethyl)benzene, OO∩OO=5,8‐dihydroxy‐1,4‐naphthoquinonato(2?), 9,10‐dihydroxy‐1,4‐anthraquinonato(2?), or 6,11‐dihydroxynaphthacene‐5,12‐dionato(2?)) by reaction with pyrazine or bipyridine linkers (N∩N=pyrazine, 4,4′‐bipyridine, 4,4′‐[(1E)‐ethene‐1,2‐diyl]bis[pyridine]) in the presence of silver trifluoromethanesulfonate (CF3SO3Ag) (Scheme). All complexes 4 – 12 were isolated in good yield as CF3SO salts, and characterized by NMR and IR spectroscopy. The host–guest properties of the metallarectangles incorporating 4,4′‐bipyridine and (4,4′‐[(1E)‐ethene‐1,2‐diyl]bis[pyridine] linkers were studied in solution by means of multiple NMR experiments (1D, ROESY, and DOSY). The largest metallarectangles 10 – 12 incorporating (4,4′‐[(1E)‐ethene‐1,2‐diyl]bis[pyridine] linkers are able to host an anthracene, pyrene, perylene, or coronene molecule in their cavity, while the medium‐size metallarectangles 7 – 9 incorporating 4,4′‐bipyridine linkers are only able to encapsulate anthracene. However, out‐of‐cavity interactions are observed between these 4,4′‐bipyridine‐containing rectangles and pyrene, perylene, or coronene. In contrast, the small pyrazine‐containing metallarectangles 4 – 6 show no interaction in solution with this series of planar aromatic molecules. 相似文献
240.
The ability of A*[s ]U dinucleosides to gel organic solvents and water is modulated by changing the nature of the substituents at O C(2′) and O C(3′), as evidenced by comparing the gelation of the dinucleosides 7 – 9 and the properties of the gels. A mere extension of the hydrophobic moiety, by replacing the isopropylidene groups of 2 by cyclohexylidene groups, as in 7 , has a small effect, while changing the conformation of the ribose ring and reducing the size of the hydrophobic moiety, as in 8 , has a strong effect on the scope of gelation, the minimum gelation concentration, as low as 0.07% for pentanol and decanol, and the properties of the gel. The fully deprotected dinucleoside 9 gels water at a minimal gelation concentration of 0.6%. A TEM of the corresponding xerogel shows the formation of fibers with a diameter of ca. 30 to 90 nm. 相似文献