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31.
Samy Chammaa Dr. Bianca Sperl Anke G. Roth Aybike Yektaoglu Steffen Renner Dr. Thorsten Berg Prof. Dr. Christoph Arenz Prof. Dr. Athanassios Giannis Prof. Dr. Tudor I. Oprea Dr. Daniel Rauh Dr. Markus Kaiser Dr. Herbert Waldmann Prof. Dr. 《Angewandte Chemie (International ed. in English)》2010,49(21):3666-3670
32.
Samy Skander Bahoura 《Comptes Rendus Mathematique》2005,341(1):25-28
We prove some a priori estimates in dimension for equations of type prescribed scalar curvature. In the particular case of the unit sphere we give an estimation of the constant c in the inequality . To cite this article: S. Skander Bahoura, C. R. Acad. Sci. Paris, Ser. I 341 (2005). 相似文献
33.
Christoph B?ttcher Jan Spengler Samy A. Essawy Klaus Burger 《Monatshefte für Chemie / Chemical Monthly》2004,30(4):853-863
N-Glycosides of Asn and homologues have been synthesized starting from hexafluoroacetone-protected -activated Asp, Glu, and Aad derivatives and glycosylamines. The synthetic value of the new building blocks was demonstrated by the concise incorporation of N-glycosylated Asn, Gln, and Aad -amides into glycopeptides. 相似文献
34.
Mirabegron is a novel β3-adrenoceptor agonist containing an amide group. It was subjected to stress conditions of acidic and alkaline hydrolyses. The hydrolytic degradation product was isolated and its structure was confirmed using mass and IR spectrometry. Two stability-indicating chromatographic methods have been proposed for the determination of mirabegron. TLC method was applied using silica gel as stationary phase and chloroform–methanol–ammonia (9.0:1.0:0.1 by volume) as the mobile phase, and chromatograms were scanned at 250 nm. Accurate determination of the drug was achieved over the concentration range of 2–12 μg per band. In addition, an isocratic HPLC method was developed on Agilent C18 column (150 mm × 4.5 mm I.D., particle size 5 µm) using ethanol-phosphate buffer pH 2.5 (30:70, by volume) as a mobile phase with flow rate of 1 mL min?1.The intact drug was detected at 250 nm with running time less than 5 min. Mirabegron was determined accurately in a concentration range of 1–25 µg mL?1. The proposed chromatographic methods were applied successfully for the assay of mirabegron in pharmaceutical dosage form and both methods were validated as per the International Conference on Harmonization guidelines and statistically compared with a reported gradient HPLC method. 相似文献
35.
Saoud A. M. Metwally Maisa I. Abdel Moneim Yasser A. Elossely Radwa I. Awad Khaled Abou-Hadeed 《Chemistry of Heterocyclic Compounds》2010,46(4):426-437
Syntheses of various derivatives of 3,5-pyrazolidenedione are reported. This includes 4-arylidene (alkylidene or aralkylidene)-3,5-pyrazolidinediones,
which on epoxidation gave unreported oxiranes. The syntheses of these derivatives were based on either the Knoevenagel reaction
of carbonyl derivatives with 3,4-pyrazolidinedione or cyclization of arylidene (alkylidene) malonic acid hydrazide with glacial
acetic acid. 4-Arylazo-3,5-pyrazolidinedione derivatives were also prepared by coupling of aryldiazonium salts with 3,5-pyrazolidinedione
or cyclization of arylazomalonic acid hydrazide. Reduction of 4-benzylidene derivatives gave the corresponding benzyl derivatives.
The structure of the new products was confirmed by elemental and spectral analyses and X-ray crystallography. 相似文献
36.
37.
There has been recent progress on inferring the structure of interactions in complex networks when they are in stationary states satisfying detailed balance, but little has been done for nonequilibrium systems. Here we introduce an approach to this problem, considering, as an example, the question of recovering the interactions in an asymmetrically coupled, synchronously updated Sherrington-Kirkpatrick model. We derive an exact iterative inversion algorithm and develop efficient approximations based on dynamical mean-field and Thouless-Anderson-Palmer equations that express the interactions in terms of equal-time and one-time-step-delayed correlation functions. 相似文献
38.
A stability-indicating reversed-phase high-performance liquid chromatography (RP-HPLC) method has been developed which can separate and accurately quantitate paracetamol, dantrolene, cetirizine and pseudoephedrine. The method was successfully validated for the purpose of conducting stability studies of the four analytes in quality control (QC) laboratories. The stability-indicating capability of the method was demonstrated by adequate separation of these four analytes from all the degradant peaks. A gradient mobile phase system consisting of (A) 50 mmol L−1 sodium dihydrogen phosphate, 5 mmol L−1 heptane sulfonic acid sodium salt, pH 4.2 and (B) acetonitrile was used with Discovery reversed-phase HS C18 analytical column (250 mm × 4.6 mm i.d., 5 μm particle size). Quantitation was achieved with UV detection at 214 nm, based on peak area.The proposed method was validated and successfully applied for the analysis of pharmaceutical formulations and laboratory-prepared mixtures containing the two multicomponent combinations. 相似文献
39.
A right R-module M is called simple-direct-injective if, whenever, A and B are simple submodules of M with A?B, and B?⊕M, then A?⊕M. Dually, M is called simple-direct-projective if, whenever, A and B are submodules of M with M∕A?B?⊕M and B simple, then A?⊕M. In this paper, we continue our investigation of these classes of modules strengthening many of the established results on the subject. For example, we show that a ring R is uniserial (artinian serial) with J2(R) = 0 iff every simple-direct-projective right R-module is an SSP-module (SIP-module) iff every simple-direct-injective right R-module is an SIP-module (SSP-module). 相似文献
40.
Cecioni S Faure S Darbost U Bonnamour I Parrot-Lopez H Roy O Taillefumier C Wimmerová M Praly JP Imberty A Vidal S 《Chemistry (Weinheim an der Bergstrasse, Germany)》2011,17(7):2146-2159
The design of multivalent glycoconjugates has been developed over the past decades to obtain high-affinity ligands for lectin receptors. While multivalency frequently increases the affinity of a ligand for its lectin through the so-called "glycoside cluster effect", the binding profiles towards different lectins have been much less investigated. We have designed a series of multivalent galactosylated glycoconjugates and studied their binding properties towards two lectins, from plant and bacterial origins, to determine their potential selectivity. The synthesis was achieved through copper(I)-catalysed azide-alkyne cycloaddition (CuAAC) under microwave activation between propargylated multivalent scaffolds and an azido-functionalised carbohydrate derivative. The interactions of two galactose-binding lectins from Pseudomonas aeruginosa (PA-IL) and Erythrina cristagalli (ECA) with the synthesized glycoclusters were studied by hemagglutination inhibition assays (HIA), surface plasmon resonance (SPR) and isothermal titration microcalorimetry (ITC). The results obtained illustrate the influence of the scaffold's geometry on the affinity towards the lectin and also on the relative potency in comparison with a monovalent galactoside reference probe. 相似文献