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61.
Jürgen Brem Monica Ioana Toşa Csaba Paizs Elemér Vass Florin Dan Irimie 《Tetrahedron: Asymmetry》2010,21(3):365-373
Starting from the racemic ethyl 3-hydroxy-3-(10-alkyl-10H-phenothiazin-3-yl)propanoates as substrates, a multienzymatic procedure was developed for the efficient synthesis of the corresponding highly enantiomerically enriched (R)- and (S)-3-heteroaryl-3-hydroxypropanoic acids. 相似文献
62.
Ioana Boca 《代数通讯》2013,41(4):1533-1554
We prove that certain algebra quotients of Hopf algebras are twisted Hopf algebras. On the other handuq (sl(2)) is a crossed product of a central subalgebra with a quotient [Ubar], when q is a root of 1. Using the cocycle involved in this crossed product we construct non-trivial complex cocycles τ and we find the isomorphism classes of the corresponding twisted Hopf algebras τ [Ubar]. These provide complex projective representations of [Ubar] which are not ordinary representations. 相似文献
63.
Leonard F. Lindoy George V. Meehan Ioana M. Vasilescu Hyun Jee Kim Ji-Eun Lee Shim Sung Lee 《Coordination chemistry reviews》2010,254(15-16):1713-1725
The transition and post-transition metal ion chemistry of a wide range of potentially pentadentate dibenzo-substituted macrocyclic ligands incorporating nitrogen, oxygen and/or sulfur donors is reviewed and shown to result in a diverse range of structural types. Aspects of metal ion recognition, bulk membrane transport, systems incorporating appended chromophores, a sulfate binding system, induced Cu(I)/Cu(II) redox switching, coordination polymers, and unsymmetric macrocyclic ligand systems are all discussed. 相似文献
64.
Mihailovic A Vladescu I McCauley M Ly E Williams MC Spain EM Nuñez ME 《Langmuir : the ACS journal of surfaces and colloids》2006,22(10):4699-4709
Here we explore DNA binding by a family of ruthenium(II) polypyridyl complexes using an atomic force microscope (AFM) and optical tweezers. We demonstrate using AFM that Ru(bpy)2dppz2+ intercalates into DNA (K(b) = 1.5 x 10(5) M(-1)), as does its close relative Ru(bpy)2dppx2+ (K(b) = 1.5 x 10(5) M(-1)). However, intercalation by Ru(phen)3(2+) and other Ru(II) complexes with K(b) values lower than that of Ru(bpy)2dppz2+ is difficult to determine using AFM because of competing aggregation and surface-binding phenomena. At the high Ru(II) concentrations required to evaluate intercalation, most of the DNA strands acquire a twisted, curled conformation that is impossible to measure accurately. The condensation of DNA on mica in the presence of polycations is well known, but it clearly precludes the accurate assessment by AFM of DNA intercalation by most Ru(II) complexes, though not by ethidium bromide and other monovalent intercalators. When stretching individual DNA molecules using optical tweezers, the same limitation on high metal concentration does not exist. Using optical tweezers, we show that Ru(phen)2dppz2+ intercalates avidly (K(b) = 3.2 x 10(6) M(-1)) whereas Ru(bpy)3(2+) does not intercalate, even at micromolar ruthenium concentrations. Ru(phen)3(2+) is shown to intercalate weakly (i.e., at micromolar concentrations (K(b) = 8.8 x 10(3) M(-1))). The distinct differences in DNA stretching behavior between Ru(phen)3(2+) and Ru(bpy)3(2+) clearly illustrate that intercalation can be distinguished from groove binding by pulling the DNA with optical tweezers. Our results demonstrate both the benefits and challenges of two single-molecule methods of exploring DNA binding and help to elucidate the mode of binding of Ru(phen)3(2+). 相似文献
65.
Ioana Ghenciu 《Monatshefte für Mathematik》2020,191(4):719-733
In this paper we introduce p-Dunford–Pettis completely continuous operators and study Banach spaces with the wp-Dunford–Pettis relative compact property (wp-DPrcP). We study the behaviour of p-Dunford–Pettis completely operators on spaces with this property. We give sufficient conditions for spaces of operators to have the wp-DPrcP. 相似文献
66.
Jürgen Brem Csaba Paizs Monica Ioana Toşa Elemér Vass Florin Dan Irimie 《Tetrahedron: Asymmetry》2009,20(4):489-496
Starting from the racemic 3-benzofuranyl- and 3-benzo[b]thiophenyl-3-hydroxypropanoic acid ethyl esters as substrates, various multistep enzymatic procedures were developed for the efficient synthesis of the corresponding highly enantiomerically enriched (R)- and (S)-3-heteroaryl-3-hydroxypropanoic acids. 相似文献
67.
68.
In this paper, a novel strategy for multicomponent analysis of two classes of pesticides such as triazines (atrazine and simazine) and phenoxyalkanoic acids (2,4-dichlorophenoxy acetic acid (2,4-D), 2,4,5-trichlorophenoxyacetic acid (2,4,5-T), 4-chlorophenoxyacetic acid (CPOAc), phenoxyacetic acid (POAc)) employing immuno-arrays is demonstrated. The approach is based on cross-reactive arrays of specific antibody pairs coupled to chemometric pattern recognition. The monoclonal antibody pairs employed in this work (atrazine-simazine and 2,4-D) are specific towards a set of analytes and preclude a particular set of others present in the sample matrix. Antibody pairs of atrazine, simazine, and 2,4-D are used to discriminate and quantify analyte of interest. Atrazine was quantified in presence of trace concentration of simazine and that of 2,4-D. The combinatorial cross-reactivity of antibody pairs towards simazine, atrazine and 2,4-D is used to distinguish among different classes of analytes and their influence on the signal suppression in immuno-techniques. These sensors exclude recognition by carbamates such as carbaryl and carbofuran. 相似文献
69.
Ioana Leuştean 《Archive for Mathematical Logic》2006,45(2):191-213
The non-commutative counterpart of the well-known Łukasiewicz propositional logic is developed, in strong connection with
the algebraic theory of psMV-algebras. An extension by a new unary logical connective is also considered and a stronger completeness result is proved
for this system. 相似文献
70.
In the selective process of the syngas conversion to synthetic gasoline a bifunctional catalytic system has to be used. It
was obtained by combination a Fischer-Tropsch catalyst with the HZSM-5 zeolite. The phase compositions of the precursor and
the fresh catalyst were established as well as the optimum thermal treatment. The catalyst was reduced in pure H2 or in a H2+CO mixture. The influence of the reduction and reaction conditions on the catalyst structure was investigated. 相似文献