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41.
Mohammed Berkhouch Ghizlane Lakhnati Marcelo Brutti Righi 《Applied Mathematical Finance》2013,20(3):295-314
ABSTRACTThe aim of this paper is to introduce a risk measure, Extended Gini Shortfall (EGS), that extends the Gini-type measures of risk and variability by taking risk aversion into consideration. Our risk measure is coherent and catches variability, an important concept for risk management. The analysis is made under the Choquet integral representations framework. We expose results for analytic computation under well-known distribution functions. Furthermore, we provide a practical application. 相似文献
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43.
The deuteron wave function is calculated integrating from outside the Schredinger equation using as input its asymptotic behaviour. Some potentials are tested and the one pion exchange potential (OPEP) is shown to be the main responsible of the wave function structure up to distances of about 1 fm. The relevance of the short range part of the potential is analyzed and it is shown that a substantial enhancement of the OPEP central part is needed in the deuteron channel. 相似文献
44.
Peri F Binassi E Manetto A Marotta E Mazzanti A Righi P Scardovi N Rosini G 《The Journal of organic chemistry》2004,69(4):1353-1356
The easily available bicyclo[3.2.0]hept-3-en-6-ones (1a-f) have been converted into the corresponding bicyclo[3.2.0]heptane-2-endo,7-endo-diols (4a-f) in an efficient and stereoselective fashion. This preparation opens a route to a family of 1,3-diols with a chiral rigid backbone, potentially suitable as nonracemic precursors for bidentate ligands in asymmetric synthesis. 相似文献
45.
Synthesis, spectral and cyclic voltammetric characterization of [Ni(dedtc)(4‐MP)2](ClO4) ( 1 ), [Ni(dedtc)(4‐MP)(NCS)]( 2 ), [Ni(dedtc)(PPh3)(NCS)] ( 3 ) and [Ni(dedtc)(PPh3)(CN)] ( 4 ) (dedtc = diethyldithiocarbamate, 4‐MP = tri(4‐methylphenyl)phosphine, PPh3 = triphenylphophine) are reported. IR spectra of complexes 1‐4 show the characteristic thioureide (C‐N) bands at higher wave numbers compared to that of the parent dithiocarbamate complex [Ni(dedtc)2]. The d‐d transitions are observed in the region 452—482 nm. The CV studies clearly show the presence of reduced electron density on the nickel ions in mixed ligand complexes 1‐4 compared to the parent dithiocarbamate. Single crystal X‐ray structure studies show all the complexes to containplanar NiS2P2, NiS2PN, and NiS2PC chromophores in keeping with the observed diamagnetism. In all the complexes the Ni‐S distances are asymmetric. The thioureide C‐N distance of the complexes 1‐4 are less thanthe C‐N distance observed in the parent [Ni(dedtc)2]. 相似文献
46.
[reaction:see text] The substituted cyclopentanic structures, 6-benzyloxymethyl-7-hydroxy-2-oxabicyclo [3.3.0]octan-3-one (1), a Corey lactone derivative, and 6-exo-benzyloxymethyl-2-oxabicyclo[3.3. 0]oct-7-en-3-one (2), have been obtained stereoselectively through the bicyclo[3.2.0]hept-3-en-6-one approach via 5-benzyloxymethyl-3-hydroxy-6-heptenoic acid, easily accessible from the inexpensive monoprotected cis-2-butene-1,4-diol. 相似文献
47.
Sylvian Cretton Alejandra Oyarzún Davide Righi Lamia Sahib Marcel Kaiser 《Natural product research》2018,32(6):695-701
A new bibenzyl derivative (4), together with two glycosylated flavonoids (1 and 2), batatasin III (3) and the phenanthrene isohircinol (5) were isolated from the aerial parts of Gavilea lutea. Their structures were elucidated on the basis of spectroscopic studies including 1D and 2D NMR, UV, IR and HRESIMS. All isolated compounds were evaluated for their antifungal activity towards Candida albicans. The new compound 4 showed inhibitory activity with a MIQ of 50 μg. In addition, compound 4 exhibited a selective activity (IC50 = 2.3 μg/mL) against Leishmania donovani. 相似文献
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49.
Ponraj Prabakaran Jebamony Justin Robert Packianathan Thomas Muthiah Gabriele Bocelli Lara Righi 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(4):459-461
In the title cocrystal, trimethoprim maleate [2,4‐diamino‐5‐(3,4,5‐trimethoxybenzyl)pyrimidin‐1‐ium maleate], C14H19N4O3+·C4H3O4?, the trimethoprim molecule is protonated at N1. The carboxyl group of the maleate ion makes a specific double hydrogen bond of type N—H?O with the 2‐amino group and the protonated N1 atom of the trimethoprim cation which is similar to the carboxylate–trimethoprim cation interaction observed in the complex of dihydrofolate reductase with trimethoprim. The pyrimidine moieties of trimethoprim cations are centrosymmetrically paired through a pair of N—H?N hydrogen bonds involving the 4‐amino group and the pyridinium N3 atom of a symmetry‐related molecule. One of the O atoms at the maleate carboxylate group bridges the 2‐amino and 4‐amino groups on either side of the paired trimethoprim cations. The other O atom of the carboxylate group forms an intramolecular O—H?O hydrogen bond with the carboxyl group. These characteristic hydrogen bonds result in infinite two‐dimensional aggregation of rings into a supramolecular ladder, which is further crosslinked through weak C—H?O interactions with methoxy groups of neighbouring trimethoprim molecules to form a layered structure. 相似文献
50.
Céline Righi 《Journal of Algebra》2008,319(4):1555-1584
We extend the results of Cellini and Papi [P. Cellini, P. Papi, Ad-nilpotent ideals of a Borel subalgebra, J. Algebra 225 (2000) 130–140; P. Cellini, P. Papi, Ad-nilpotent ideals of a Borel subalgebra II, J. Algebra 258 (2002) 112–121] on the characterizations of ad-nilpotent and abelian ideals of a Borel subalgebra to parabolic subalgebras of a simple Lie algebra. These characterizations are given in terms of elements of the affine Weyl group and faces of alcoves. In the case of a parabolic subalgebra of a classical simple Lie algebra, we give formulas for the number of these ideals. 相似文献