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41.
Tatiana B. Mikenas Vladimir A. Zakharov Lyudmila G. Echevskaya Michail A. Matsko 《Journal of polymer science. Part A, Polymer chemistry》2005,43(10):2128-2133
Data on ethylene polymerization over supported LFeCl2/MgCl2 catalysts {L = 2,6‐bis[1‐(2,6‐dimethylphenylimino)ethyl]pyridyl} containing AlR3 (R = Me, Et, i‐Bu, or n‐Oct) as an activator are presented. These catalysts are highly active (100–300 kg of polyethylene/g of Fe h bar of C2H4) and stable in ethylene polymerization at 70–80 °C. Data on the effects of the iron content, AlR3 type, Al(i‐Bu)3 concentration, and hydrogen presence on the catalyst activity are presented. The molecular structure of polyethylene produced with these catalysts (including the molecular masses, molecular mass distribution, branching, and number of C?C bonds) has been studied; data on the effects of AlR3 and hydrogen on the molecular structure are presented. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 2128–2133, 2005 相似文献
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Athanasekos L Vasileiadis M Tsigara A Kaminska E Piotrowska A Alexandropoulos D Sigalas MM Vainos NA 《Optics letters》2010,35(23):4003-4005
We designed and fabricated multilayer metal/metal-oxide surface relief diffractive grating structures by growing alternating Pt and SnO(x) layers. Optical interrogation at 633 nm reveals the temperature dependence of their reflection and transmission diffractive effects. This function is explored here in the context of a remote, spatially localized, photonic temperature sensing operation, achieving sensitivity of 10% per °C for the zeroth-order in the transmission mode. The experimental demonstration is found to be in good agreement with the results of rigorous coupled wave analysis of the composite metal/metal-oxide element. 相似文献
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Let F be an algebraically closed field and let A and B be arbitrary finite dimensional simple algebras over F. We prove that A and B are isomorphic if and only if they satisfy the same identities. 相似文献
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Michail Papadourakis Stefano Bosisio Julien Michel 《Journal of computer-aided molecular design》2018,32(10):1047-1058
In the context of the SAMPL6 challenges, series of blinded predictions of standard binding free energies were made with the SOMD software for a dataset of 27 host–guest systems featuring two octa-acids hosts (OA and TEMOA) and a cucurbituril ring (CB8) host. Three different models were used, ModelA computes the free energy of binding based on a double annihilation technique; ModelB additionally takes into account long-range dispersion and standard state corrections; ModelC additionally introduces an empirical correction term derived from a regression analysis of SAMPL5 predictions previously made with SOMD. The performance of each model was evaluated with two different setups; buffer explicitly matches the ionic strength from the binding assays, whereas no-buffer merely neutralizes the host–guest net charge with counter-ions. ModelC/no-buffer shows the lowest mean-unsigned error for the overall dataset (MUE 1.29?<?1.39?<?1.50 kcal mol?1, 95% CI), while explicit modelling of the buffer improves significantly results for the CB8 host only. Correlation with experimental data ranges from excellent for the host TEMOA (R2 0.91?<?0.94?<?0.96), to poor for CB8 (R2 0.04?<?0.12?<?0.23). Further investigations indicate a pronounced dependence of the binding free energies on the modelled ionic strength, and variable reproducibility of the binding free energies between different simulation packages. 相似文献
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LetAbe a PI-algebra over a fieldF. We study the asymptotic behavior of the sequence of codimensionscn(A) ofA. We show that ifAis finitely generated overFthenInv(A)=limn→∞
always exists and is an integer. We also obtain the following characterization of simple algebras:Ais finite dimensional central simple overFif and only ifInv(A)=dim=A. 相似文献
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Michail K Matzi V Maier A Herwig R Greilberger J Juan H Kunert O Wintersteiger R 《Analytical and bioanalytical chemistry》2007,387(8):2801-2814
Hydroxymethylfurfural (HMF), a well-known heterocyclic Maillard reaction product, has often been studied for its potential
toxic, mutagenic, and carcinogenic effects. Recent clinical studies, however, have strongly suggested that HMF might have
exciting antitumor potential. We report on the development and validation of a bioanalytical assay for HMF that could be suitable
as a basis for pharmacokinetic models in cancer patients. Two strategies were tested, i.e., direct and indirect methodologies.
A direct isocratic LC determination at 283 nm was designed. Two indirect attempts involved derivatization coupled to HPLC-UV.
It was possible to resolve the stereoisomers of the HMF derivative, and factors influencing their equilibrium ratio are discussed.
HMF was extracted from the biomatrix by solid-phase extraction using different cartridges. A comparative study was made of
the implemented methods as well as the extraction protocols. Both indirect assays proved to be more sensitive and were used
to assess HMF quantitatively in human plasma. However, the newly introduced derivatization conditions led to the highest sensitivity
with a LOD (S/N ratio = 3) of at least 2 pmol analyte on column. The assay selectivity was satisfactory in pre- and post-dose
real samples. The mean recoveries of the assays were 79% and 89%, with acceptable accuracies and reproducibilities.
Figure Schematic representation of hydroxymethylfurfural (HMF) in human plasma 相似文献
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