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排序方式: 共有393条查询结果,搜索用时 171 毫秒
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Norberto Garcia‐Cairasco Miguel Moyses‐Neto Flavio DelVecchio Jos A. C. Oliveira Francisco L. dosSantos Olagide W. Castro Gabriel M. Arisi Mrcio Dantas Ruither O. G. Carolino Joaquim Coutinho‐Netto Andre L. A. Dagostin Marcelo C. A. Rodrigues Ricardo M. Leo Samir A. P. Quintiliano Luiz F. Silva Leonardo Gobbo‐Neto Norberto P. Lopes 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2013,125(49):12981-12981
183.
Dickson Maria Michela Espa Giuseppe Giuliani Diego Santi Flavio Savadori Lucia 《Nonlinear dynamics》2020,101(3):1833-1846
Nonlinear Dynamics - This paper aims at investigating empirically whether and to what extent the containment measures adopted in Italy had an impact in reducing the diffusion of the COVID-19... 相似文献
184.
Gabriel Cendejas Csar Andrs Flores-Sandoval Nelson Huitrn Rafael Herrera Luis S. Zamudio-Rivera Hiram I. Beltrn Flavio Vzquez 《Journal of Molecular Structure》2008,879(1-3):40-52
In this work, the influence of three different initiators (KOH, KOH dissolved in ethanol and the potassium salt of ethylene glycol) on the propylene oxide polymerization was studied by experimental and theoretical methods. A first series of reactions was carried out to establish the adequate thermal conditions for a minimal monomer transfer during the polymerization. The formation of end insaturations (main consequence of the monomer transfer interference) in the poly(propylene oxide) chains was studied by spectroscopic methods. Furthermore, a second series of poly(propylene oxide)s was prepared by using the mentioned initiators, and characterized by size exclusion chromatography. The initiator efficiency to create active centers in every reactive system was determined from the molecular weight and the conversion data obtained. Experimental results were elucidated by using quantum chemical calculations at density functional theory level, involving thermo-chemistry parameters, and the simulation of the infrared, and 13C nuclear magnetic resonance spectra. This method led to studying the addition of up to ten propylene oxide unit, resulting into important energetic tendencies and regioselectivity, being compared to the physicochemical data of products obtained. These correlations meant further understanding of the reaction course and the type of products obtained, depending on the nature of the initiator. 相似文献
185.
Adele Mucci Luisa Schenetti Maria A. Vandelli Barbara Ruozi Gianfranco Salvioli Flavio Forni 《Supramolecular chemistry》2013,25(4):427-433
Abstract The formation and geometry of the hyodeoxycholic acid (HDCA)/2-hydroxypropyl-β-cyclodextrin (HPβCD) complex in methanol-d4 solution was determined through a rotating frame nuclear Overhauser (ROESY) experiment. The reported results confirmed those independently and previously obtained though the use of 13C complexation shifts in the same solvent. The 13C approach, which needs shorter experimental times and is currently used in the study of HPβCD/bile acid systems, was then substantiated. 相似文献
186.
Cazzani Antonio Serra Mauro Stochino Flavio Turco Emilio 《Continuum Mechanics and Thermodynamics》2020,32(3):665-692
Continuum Mechanics and Thermodynamics - This work discusses some alternate models of a mixed assumed strain finite element which has been developed for laminated plates. After a brief theoretical... 相似文献
187.
Keelara Abiraj Dr. Rosalba Mansi Dr. Maria‐Luisa Tamma Flavio Forrer Dr. Renzo Cescato Dr. Jean Claude Reubi Prof. Kayhan G. Akyel Helmut R. Maecke Prof. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(7):2115-2124
Owing to its optimal nuclear properties, ready availability, low cost and favourable dosimetry, 99mTc continues to be the ideal radioisotope for medical‐imaging applications. Bifunctional chelators based on a tetraamine framework exhibit facile complexation with Tc(V)O2 to form monocationic species with high in vivo stability and significant hydrophilicity, which leads to favourable pharmacokinetics. The synthesis of a series of 1,4,8,11‐tetraazaundecane derivatives ( 01 – 06 ) containing different functional groups at the 6‐position for the conjugation of biomolecules and subsequent labelling with 99mTc is described herein. The chelator 01 was used as a starting material for the facile synthesis of chelators functionalised with OH ( 02 ), N3 ( 04 ) and O‐succinyl ester ( 05 ) groups. A straightforward and easy synthesis of carboxyl‐functionalised tetraamine‐based chelator 06 was achieved by using inexpensive and commercially available starting materials. Conjugation of 06 to a potent bombesin‐antagonist peptide and subsequent labelling with 99mTc afforded the radiotracer 99mTc‐N4‐BB‐ANT, with radiolabelling yields of >97 % at a specific activity of 37 GBq μmol?1. An IC50 value of (3.7±1.3) nM was obtained, which confirmed the high affinity of the conjugate to the gastrin‐releasing‐peptide receptor (GRPr). Immunofluorescence and calcium mobilisation assays confirmed the strong antagonist properties of the conjugate. In vivo pharmacokinetic studies of 99mTc‐N4‐BB‐ANT showed high and specific uptake in PC3 xenografts and in other GRPr‐positive organs. The tumour uptake was (22.5±2.6) % injected activity per gram (% IA g?1) at 1 h post injection (p.i.). and increased to (29.9±4.0) % IA g?1 at 4 h p.i. The SPECT/computed tomography (CT) images showed high tumour uptake, clear background and negligible radioactivity in the abdomen. The promising preclinical results of 99mTc‐N4‐BB‐ANT warrant its potential candidature for clinical translation. 相似文献
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