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71.
Tadahisa Funaki Yueyuan Gao Danielle Hilhorst 《Mathematical Methods in the Applied Sciences》2020,43(9):5860-5886
In this paper, we prove the existence and uniqueness of the entropy solution for a first-order stochastic conservation law with a multiplicative source term involving a -Brownian motion. After having defined a measure-valued weak entropy solution of the stochastic conservation law, we present the Kato inequality, and as a corollary, we deduce the uniqueness of the measure-valued weak entropy solution, which coincides with the unique weak entropy solution of the problem. The Kato inequality is proved by a doubling of variables method; to that purpose, we prove the existence and the uniqueness of the strong solution of an associated stochastic nonlinear parabolic problem by means of an implicit time discretization scheme; we also prove its convergence to a measure-valued entropy solution of the stochastic conservation law, which proves the existence of the measure-valued entropy solution. 相似文献
72.
Dr. Kara M. Harmatys Dr. Juan Chen Danielle M. Charron Dr. Christina M. MacLaughlin Prof. Dr. Gang Zheng 《Angewandte Chemie (International ed. in English)》2018,57(27):8125-8129
Current biomimetics for medical applications use a single biomimetic approach to imitate natural structures, which can be insufficient for reconstructing structurally complex natural systems. Multipronged efforts may resolve these complexities. To achieve interesting nanostructure‐driven optical properties, a dual‐biomimetic system contained within a single nanoagent was engineered to recapitulate chlorosomes, efficient light‐harvesting organelles that have unique dye assemblies and tunable photonic properties. A series of chlorin dyes was synthesized, and these hydrophobic assemblies were stabilized inside a high‐density lipoprotein, a second biomimetic that enabled in vivo utility. This system resulted in tunable tumor imaging of intact (photoacoustic) and disrupted (activatable fluorescence) nanostructures. The successful demonstration of this multipronged biomimetic approach opens the door for reconstruction of complex natural systems for biomedical applications. 相似文献
73.
A new heterogeneous catalyst composed of copper and nickel oxide particles supported within charcoal has been developed. It catalyzes cross-couplings that traditionally use palladium, nickel, or copper, including Suzuki-Miyaura reactions, Buchwald-Hartwig aminations, vinylalane alkylations, etherifications of aryl halides, aryl halide reductions, asymmetric conjugate reductions of activated olefins, and azide-alkyne "click" reactions. 相似文献
74.
Schriemer DC Kemmer D Roberge M 《Combinatorial chemistry & high throughput screening》2008,11(8):610-616
Cell-based screening using phenotypic assays is a useful means of identifying bioactive chemicals for use as tools to elucidate complex cellular processes. However, the chemicals must display sufficient selectivity and their targets have to be identified. We describe how cell-based screening assays can be designed to maximize the likelihood of discovering selective compounds through the choice of positive readouts, low chemical concentrations and long incubation periods. Examining the potency, efficacy and activity range of chemicals can further help set apart those likely to act more specifically. Identifying the cellular targets of active chemicals can be especially demanding. Secondary screens and the cautious use of the candidate approach can help narrow down their mechanisms of action, but biased approaches may lead to the identification of secondary or even irrelevant targets. We discuss strategies for unbiased target identification by sampling potential targets at the genome-wide and proteome-wide levels. 相似文献
75.
76.
Parallel factor analysis (PARAFAC) was used to analyze data from the high throughput screening of an array of organometallic rhodium and iridium complexes as catalysts for the intramolecular hydroamination of 2-(2-phenylethynyl)aniline to give 2-phenylindole. The progress of the hydroamination reactions was monitored using UV-visible spectroscopy. The overlapped UV-visible spectra of the mixture of starting material, product and solvent in the samples taken at different times were deconvoluted using PARAFAC. Unique PARAFAC models led to close approximations of the actual UV-visible spectra of the compounds in the mixture. The performance of the catalysts was then compared by estimating the final concentration of the starting material and product using PARAFAC loadings. A library of 63 complexes generated in situ was examined in a single experiment using this methodology. The complexes were generated from combinations of seven ligands (bis(N-methyl2-imidazolyl)methane, bis(1-pyrazolyl)methane, 1,10-phenanthroline, N,N'-bis(p-tolyl)diazabutadiene, N,N'-bis(p-tolyl)1,2-dimethyldiazabutadiene, N,N'-bis(mesityl)1,2-dimethyldiazabutadiene and bis(2,4,6-trimethylphenylimino)acenapthene) and nine metal precursors ([Ir(COD)Cl](2) (COD = 1,5-cyclooctadiene), [Ir(CO)(2)Cl](n), [Ir(COE)(2)Cl](2), [IrCp*Cl(2)](2) (Cp* = 1,2,3,4,5-pentamethylcyclopentadiene), [Rh(COD)Cl](2), [Rh(CO)(2)Cl](2), [Rh(COE)(2)Cl](2), [RhCp*Cl(2)](2) and [RhCpCl(2)](2)) (Cp = cyclopentadiene)). The proposed method can be used for the fast screening of arrays of metal complexes for identifying effective catalysts, providing information that can augment traditional methods used for the analysis of catalyzed reactions. 相似文献
77.
Evan G. Robertson Danielle E. Martin Chris D. Thompson Richard J.S. Morrison John G. Philis 《Chemical physics letters》2008,463(1-3):29-32
Sec-butylbenzene has been investigated using resonant two-photon ionization (R2PI) and UV–UV hole-burning spectroscopy aided by ab initio calculations. All three conformers predicted from theory are observed in the spectrum, and are assigned by rotational band contour analysis. The most strongly populated conformer (G1) has a gauche arrangement of the side chain dihedral angle τ2(C1CαCβCγ). The populations of the anti (A) and the remaining gauche conformer (G2) are about 7% and 2%, respectively. The alpha methyl group is found to significantly affect the conformational preferences in sec-butylbenzene (sec-BB), compared to n-propylbenzene in which the anti conformer is favored. 相似文献
78.
A computational study of the relative stability of the monolacunary Keggin polyoxotungstates alpha and beta 3-[XW 11O 39] ( m- ) (X = P, m = 7; X = Si, m = 8) was performed. The influence of the nature of different grafted cations and of the central anion XO 4 ( n- ) on the relative stabilities of the lacunary isomers was analyzed. From these results, an interpretation of the structural difference in the metallic frameworks of alpha-[PW 11O 39{Ru(DMSO) 3(H 2O)}] (5-), alpha-[PW 11O 39{Ru(C 6H 6)(H 2O)}] (5-), and beta 3-[SiW 11O 39{Ru(DMSO) 3(H 2O)}] (6-) is proposed, and conclusions are drawn as to how to favor the formation of beta 3 derivatives in future syntheses. 相似文献
79.
YCo 0.88Ga 3Ge has an incommensurately modulated structure that was solved with (3 + 1)D superspace techniques. YCo 0.88Ga 3Ge crystallizes in the orthorhombic superspace group Immm(alpha00)00 s with unit cell constants of a = 4.1639(4), b = 4.1639(4), c = 23.541(2) A and a modulation vector of q = 0.3200(4) a* at 293 K. The incommensurate modulation, which creates a very large supercell ( approximately 25 fold), arises from a charge density wave (CDW) in the square net of Ga atoms that is coupled with a site occupancy wave (SOW) of Co atoms. The distorted Ga net features polygallide ribbons, chains, as well as single atoms. Temperature dependent crystallographic studies of the structure from 100-500 K indicate that the CDW is "locked in". Electrical conductivity and thermopower measurements in the temperature range of 300-500 K show that YCo 0.88Ga 3Ge is a poor metal. 相似文献
80.
Kippeny TC Bowers MJ Dukes AD McBride JR Orndorff RL Garrett MD Rosenthal SJ 《The Journal of chemical physics》2008,128(8):084713
The exciton dynamics of CdSe nanocrystals are intimately linked to the surface morphology. Photo-oxidation of the selenium surfaces of the nanocrystal leads to an increase in radiative decay efficiency from both the band edge and deep trap emission states. The addition of the primary amine hexadecylamine curtails nonradiative excitonic decay attributed to the dangling surface selenium orbitals by passivation of those trap sites by the methylene protons on the amine, leading to enhanced band edge emission and the absence of deep trap emission. Furthermore, CdSeZnSe core/shell nanocrystals are not immune from contributions from surface states because of the alignment of the band structures of the core and shell materials. 相似文献