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771.
R. Alizadeh 《Linear algebra and its applications》2012,437(6):1422-1425
772.
A series of 2-substituted-1H-benzimidazole derivatives were synthesized and evaluated for antimicrobial, antifungal and cytotoxic activities. The results showed that all tested compounds showed potent antimicrobial activity against some species of Gram-negative bacteria (Pseudomonas aeruginosa, Escherichia coli, Salmonella typhi) and fungi (Candida albicans) with minimum inhibitory concentrations (MICs) lower than 0.016 μg/mL. In contrast, all tested compounds were inactive against Staphylococcus aureus (Gram-positive bacterium). The final targets were also tested for their antitumor activity in vitro on cervical carcinoma (HeLa) cell line. Eight of the test compounds displayed more potent cytotoxic effect than doxorubicin at nanomolar concentrations. Compounds 2c and 3c exerted the strongest cytoyoxic effect with IC(50) 15 and 13 nM, respectively. 相似文献
773.
Let 1≦m≦4 be a fixed integer and let f:X→Y be a mapping with X, Y two vector spaces. The functional equation (1.1) is said to be additive if m=1, quadratic if m=2, cubic if m=3 and quartic if m=4, respectively. For convenience, a solution of (1.1) will be called an m-mapping. Let $\mathcal{A}$ , $\mathcal{B}$ be two algebras. An m-mapping $f\colon \mathcal{A} \to \mathcal{B}$ will be called m-derivation if the equality f(xy)=x m f(y)+f(x)y m is fulfilled for all $x,y\in \mathcal{A}$ . In this paper, we use a fixed point method to prove the stability and hyperstability of m-derivations on Banach algebras. 相似文献
774.
RSeCCPh (1a, R = Et; 1b, R = n-Bu; 1c, R = Ph; 1d, R = 2,4,6-Me3C6H2) reacts with equimolar amounts of Fe2(CO)9 (2) to give [(μ-SeR)(μ-σ,π-CCPh)]Fe2(CO)6 (3a, R = Et; 3b, R = n-Bu; 3c, R = Ph; 3d, R = 2,4,6-Me3C6H2).Complexes 3a-3d exist as two isomers, depending on the axial or equatorial position of R at selenium.Addition of P(OiC3H7)3 (4) to 3d affords {(μ-Se-2,4,6-Me3C6H2)[μ-η1-CCPh(P(OiC3H7)3)]}Fe2(CO)6 (5) along with {(μ-Se-2,4,6-Me3C6H2)[μ-η1:η1-PhCC(P(OiC3H7)3)]}Fe2(CO)6 (6).The solid-state structures of 3d, 5 and 6 were determined by single X-ray structure analysis.In mononuclear 3d the Fe(CO)3 fragments are bridged by a μ-Se-2,4,6-Me3C6H2 and a μ-σ,π-CCPh unit, resulting in an over-all butterfly arrangement.Due to steric reasons, the mesityl group is pointing away from the PhCC entity and hence, is located in an equatorial position.Compounds 5 and 6, which co-crystallise in the ratio of 7:93, feature aμ-bridging 2,4,6-Me3C6H2Se unit and either a vinylidenic CCPh(P(OiC3H7)3) (complex 5) or a olefinic PhCC(P(OiC3H7)3) (complex 6) building block of which the latter entity is part of a diiron cyclobutene ring. 相似文献
775.
A 4-(2-pyridylazo)-resorcinol (PAR)-modified carbon ceramic electrode (CCE) prepared by the sol-gel technique has been reported for the first time in this paper. By immersing the CCE in aqueous solution of PAR (0.001 mol L−1), after a short period of time, a thin film of PAR was rapidly formed on the surface of the electrode due to its strong adsorption properties. A differential pulse anodic stripping voltammetric (DPASV) method was developed for determination of Ag(I) at the modified carbon ceramic electrode. The analysis procedure consisted of an open circuit accumulation step in a sample solution which was continuously stirred for 12 min. This was followed by replacing the medium with a clean solution where the accumulated Ag(I) was reduced for 15 s in −0.6 V. Then, the potential was scanned from −0.2 to +0.2 V to obtain the voltammetric peak. The detection limit of silver(I) was 0.123 μg L−1, and for seven successive determinations of 10, 100 and 200 μg L−1 Ag(I), the relative standard deviations were 2.1, 1.4 and 1.03%, respectively. The calibration curve was linear for 0.5-300 μg L−1 silver(I). The procedure was applied to determine silver(I) in X-ray photographic films and super-alloy samples. 相似文献
776.
The unusual 1:2 intermediate, generated by the addition of triphenylphosphine (TPP) to dialkyl acetylenedicarboxylates (DAAD) was trapped during the reaction of a Ph3P/RN = C/DMAD binucleophilic system with TFA as an initial proton source in a pseudo-seven-component (7-CR) diastereoselective reaction to give λ5-phosphanylidene bis(2,5-dioxotetrahydro-1H-pyrrole-3-carboxylates) with three stereogenic centers and a phosphorane group in good yields. 相似文献
777.
New unsymmetrical diamine monomer containing triaryl imidazole pendent group,4-[4-(4,5-diphenyl-1H-imidazol-2-yl)phenoxy] -1,3-benzenediamine,was synthesized via aromatic substitution reaction of 1-chloro-2,4-dinitrobenzene with 4-(4,5- diphenyl-1H-imidazol-2-yl)phenol,followed by palladium-catalyzed hydrazine reduction.This new monomer was further confirmed by FT-IR,~1H NMR and ~(13)C NMR.Novel polyamides having pendant triaryl imidazole group were prepared by the phosphorylation polycondensation of fou... 相似文献
778.
This article reviews a new developing method in the field of metal oxide reduction in chemical and metallurgical processes, which uses methane as a reducing agent. Commonly, coal is used as the reducing agent in the reduction of metal oxide and other inorganic materials; Metal producing factories are among the most intensive and concentrated source of greenhouse gases and other pollutants such as heavy metals, sulfur dioxide and fly ash. Thermodynamically, methane has a great reducing capability and can be activated to produce synthesis gas over a metal oxide as an oxygen donor. Metal oxide reduction and methane activation, two concurrent thermochemical processes, can be combined as an efficient and energy-saving process; nowadays this kind of technologies is of great importance. This new reduction process could improve energy efficiencies and significantly decrease greenhouse gas emission compared to the conventional process; furthermore, the produced gases are synthesis gas that is more valuable than methane. In this paper, thermodynamic studies and advantages of this promising method were discussed. The major aim of this article is to introduce methane as a best and environmentally friendly reducing agent at low temperature. 相似文献
779.
R. Alizadeh 《Linear algebra and its applications》2009,430(1):574-119
Let A be a unital associative ring and M be a 2-torsion free A-bimodule. Using an elementary and constructive method we show that every Jordan derivation from Mn(A) into Mn(M) is a derivation. 相似文献
780.
We consider bifunctions ${F : C\times C\rightarrow \mathbb{R}}$ where C is an arbitrary subset of a Banach space. We show that under weak assumptions, monotone bifunctions are locally bounded in the interior of their domain. As an immediate corollary, we obtain the corresponding property for monotone operators. Also, we show that in contrast to maximal monotone operators, monotone bifunctions (maximal or not maximal) can also be locally bounded at the boundary of their domain; in fact, this is always the case whenever C is a locally polyhedral subset of ${\mathbb{R}^{n}}$ and F(x, ·) is quasiconvex and lower semicontinuous. 相似文献