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101.
Finite difference scheme for variational inequalities 总被引:2,自引:0,他引:2
E. A. Al-Said M. A. Noor A. K. Khalifa 《Journal of Optimization Theory and Applications》1996,89(2):453-459
In this paper, we show that a class of variational inequalities related with odd-order obstacle problems can be characterized by a system of differential equations, which are solved using the finite difference scheme. The variational inequality formulation is used to discuss the uniqueness and existence of the solution of the obstacle problems. 相似文献
102.
N. M. Khalifa E. S. Nossier M. A. Al-Omar A. E. Amr 《Russian Journal of General Chemistry》2016,86(8):1948-1953
Series of novel substituted thioxopyrimidine and thiazolo[3,2-a]pyrimidine compounds that combine various heteroaryl rings have been synthesized via Biginelli one-pot three-component reaction and elucidated with chemical and spectral analysis. Several products were tested for their antimicrobial properties. 相似文献
103.
Two simple and sensitive spectrophotometric and fluorimetric methods for the determination of tranexamic acid in tablets are developed. The methods are based on condensation the primary amino group of tranexamic acid with acetyl acetone and formaldehyde producing a yellow coloured product, which is measured spectrophotometrically at 335 nm or fluorimetrically at 480 nm the colour was stable for at least 1 h. Beer's law was valid within a concentration rang of 0.05-2.0 microg ml-1 spectrophotometrically and 0.05-0.25 microg ml-1 fluorimetrically. All the variables were studied to optimize the reaction conditions. No interference was observed in the presence of common pharmaceutical excipints. The validity of both methods was tested by analyzing tranexamic acid in its pharmaceutical preparations. Good recoveries were obtained and the results were comparable with those obtained by standard method. 相似文献
104.
In this paper, we establish new versions of Hardy's and Miyachi's theorems for the Bessel–Struve transform. 相似文献
105.
Russian Journal of General Chemistry - A series of new 1-{[1-(3-chlorophenyl)-3-(4-methoxyphenyl)-1H-pyrazol-4-yl]methyleneamino}-6-amino-1,2-dihydro-4-(substitutedphenyl)-2-oxopyridine-3,5-di... 相似文献
106.
A stable solution of (cobalt(III)(salen))2O2 was prepared under optimum conditions for its use for the potentiometric determination of xylenols, hydroquinone, sodium thiosulfate, and sodium metabisulfite, by iodide reduction of unreacted cobalt(III) complex and back titrating excess iodide with mercury(II) using silver amalgum and SCE combination. The possible schemes for the course of the redox reactions were suggested. The procedure was also evaluated in comparison with those mentioned in the literature. 相似文献
107.
Rapid potentiometric method was adopted for the determination of small amounts of hexacyanoferrate(II), thiosulfate, thiocyanate, and ascorbic acid, based on oxidation with ethanolic iodine at different pH values and subsequently titration of iodide with mercury(II) using silver amalgam as indicator electrode. The potential breaks at the vicinity of the endpoints were sharp enough for their accurate detection. The method provides for accurate determination of small amounts of some reductants of analytical importance. 相似文献
108.
Ibrahim H. Eissa Mohamed M. Khalifa Eslam B. Elkaeed Elsayed E. Hafez Aisha A. Alsfouk Ahmed M. Metwaly 《Molecules (Basel, Switzerland)》2021,26(20)
In continuation of our previous effort, different in silico selection methods were applied to 310 naturally isolated metabolites that exhibited antiviral potentialities before. The applied selection methods aimed to pick the most relevant inhibitor of SARS-CoV-2 nsp10. At first, a structural similarity study against the co-crystallized ligand, S-Adenosyl Methionine (SAM), of SARS-CoV-2 nonstructural protein (nsp10) (PDB ID: 6W4H) was carried out. The similarity analysis culled 30 candidates. Secondly, a fingerprint study against SAM preferred compounds 44, 48, 85, 102, 105, 182, 220, 221, 282, 284, 285, 301, and 302. The docking studies picked 48, 182, 220, 221, and 284. While the ADMET analysis expected the likeness of the five candidates to be drugs, the toxicity study preferred compounds 48 and 182. Finally, a density-functional theory (DFT) study suggested vidarabine (182) to be the most relevant SARS-Cov-2 nsp10 inhibitor. 相似文献
109.
110.
Khalifa El Mabrouk 《Positivity》2006,10(4):665-680
We obtain a characterization of all locally bounded functions p ≥ 0 for which the equation (E) Δu +p(x)ψ(u) = 0 has a positive solution in Ω vanishing on the boundary, where Ω is a domain of ℝN and ψ > 0 is a nonincreasing continuous function on ]0,∞[. In particular, for Ω = ℝN with N ≥ 3, it is shown that (E) has a (unique) positive solution in ℝN which decays to zero at infinity if and only if the set {p > 0} has positive Lebesgue measure and
This condition can be replaced by if p is radial. 相似文献