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R. Aryaeinejad E. L. Reber J. K. Jewell J. D. Cole M. W. Drigert 《Journal of Radioanalytical and Nuclear Chemistry》2005,264(1):155-162
Summary In this work, prompt gamma-rays emitted by thermal neutron-induced fission decay using fast coincidence techniques are used to identify both light and heavy fragments and obtain gamma-ray signatures and radiation multiplicity. The measurements were carried out with 235U and 239Pu targets using the Intense Pulsed Neutron Source (IPNS) at Argonne National Laboratory. This study reports the recent results of a preliminary analysis of experimental data collected from the induced fission of 235U and 239Pu. In this paper, we discuss how these results could be used to characterize an unknown sample of fissile material. 相似文献
114.
Belous K Shapkin M Sokolov A Abe K Abe K Adachi I Aihara H Anipko D Arinstein K Aulchenko V Aushev T Bakich AM Barberio E Bay A Bedny I Bitenc U Bizjak I Blyth S Bondar A Bozek A Bracko M Browder TE Chang MC Chen A Chen KF Chen WT Cheon BG Chistov R Choi Y Choi YK Cole S Dalseno J Drutskoy A Eidelman S Epifanov D Fratina S Fujikawa M Gabyshev N Gershon T Gokhroo G Golob B Ha H Haba J Hasegawa Y Hayasaka K Hayashii H Hazumi M Heffernan D Hokuue T Hoshi Y Hou S Hou WS Iijima T Ikado K Imoto A 《Physical review letters》2007,99(1):011801
The mass of the tau lepton has been measured in the decay mode tau-->3pinutau using a pseudomass technique. The result obtained from 414 fb-1 of data collected with the Belle detector is Mtau=[1776.61+/-0.13(stat)+/-0.35(sys)] MeV/c2. The upper limit on the relative mass difference between positive and negative tau leptons is |Mtau+-Mtau-|/Mtau<2.8 x 10-4 at 90% confidence level. 相似文献
115.
Whitham modulation equations are derived for the nonlinear Schrödinger equation in the plane ((2+1)-dimensional nonlinear Schrödinger [2d NLS]) with small dispersion. The modulation equations are obtained in terms of both physical and Riemann-type variables; the latter yields equations of hydrodynamic type. The complete 2d NLS Whitham system consists of six dynamical equations in evolutionary form and two constraints. As an application, we determine the linear stability of one-dimensional traveling waves. In both the elliptic and hyperbolic cases, the traveling waves are found to be unstable. This result is consistent with previous investigations of stability by other methods and is supported by direct numerical calculations. 相似文献
116.
Spontaneous Reconstitution of Functional Transmembrane Proteins During Bioorthogonal Phospholipid Membrane Synthesis
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Christian M. Cole Dr. Roberto J. Brea Young Hun Kim Michael D. Hardy Prof. Jerry Yang Prof. Neal K. Devaraj 《Angewandte Chemie (International ed. in English)》2015,54(43):12738-12742
Transmembrane proteins are critical for signaling, transport, and metabolism, yet their reconstitution in synthetic membranes is often challenging. Non‐enzymatic and chemoselective methods to generate phospholipid membranes in situ would be powerful tools for the incorporation of membrane proteins. Herein, the spontaneous reconstitution of functional integral membrane proteins during the de novo synthesis of biomimetic phospholipid bilayers is described. The approach takes advantage of bioorthogonal coupling reactions to generate proteoliposomes from micelle‐solubilized proteins. This method was successfully used to reconstitute three different transmembrane proteins into synthetic membranes. This is the first example of the use of non‐enzymatic chemical synthesis of phospholipids to prepare proteoliposomes. 相似文献
117.
A Visible‐Light‐Mediated Radical Smiles Rearrangement and its Application to the Synthesis of a Difluoro‐Substituted Spirocyclic ORL‐1 Antagonist
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Dr. James J. Douglas Haley Albright Martin J. Sevrin Dr. Kevin P. Cole Prof. Corey R. J. Stephenson 《Angewandte Chemie (International ed. in English)》2015,54(49):14898-14902
A visible‐light‐mediated radical Smiles rearrangement has been developed to address the challenging synthesis of the gem‐difluoro group present in an opioid receptor‐like 1 (ORL‐1) antagonist that is currently in development for the treatment of depression and/or obesity. This method enables the direct and efficient introduction of the difluoroethanol motif into a range of aryl and heteroaryl systems, representing a new disconnection for the synthesis of this versatile moiety. When applied to the target compound, the photochemical step could be conducted on 15 g scale using industrially relevant [Ru(bpy)3Cl2] catalyst loadings of 0.01 mol %. This transformation is part of an overall five‐step route to the antagonist that compares favorably to the current synthetic sequence and demonstrates, in this specific case, a clear strategic benefit of photocatalysis. 相似文献
118.
[Mg(Form)2(THF)] [Form = bis(2,6‐dimethylphenyl)formamidinate (XylForm) ( 1 ), bis(2,6‐diethylphenyl)formamidinate, (EtForm) ( 2 ), bis(2,6‐diisopropylphenyl)formamidinate (DippForm) ( 3 )] are conveniently synthesized by treating bis(2,6‐dimethylphenyl)formamidine, bis(2,6‐diethylphenyl)formamidine, or bis(2,6‐diisopropylphenyl)formamidine, respectively, with half an equivalent of dibutylmagnesium in THF. Compounds 1 – 3 are mononuclear species in the solid state with five coordinate central metal atoms. The 1H NMR chemical shift of the formamidinate formyl proton exhibits a correlation with ligand sterics wherein increasing bulk leads to a shift to higher field. 相似文献
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Biofunctionalization of Polyoxometalates with DNA Primers,Their Use in the Polymerase Chain Reaction (PCR) and Electrochemical Detection of PCR Products
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Dr. Ahmed M. Debela Dr. Mayreli Ortiz Dr. Valerio Beni Prof. Serge Thorimbert Dr. Denis Lesage Prof. Richard B. Cole Prof. Ciara K. O'Sullivan Prof. Bernold Hasenknopf 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(49):17721-17727
The bioconjugation of polyoxometalates (POMs), which are inorganic metal oxido clusters, to DNA strands to obtain functional labeled DNA primers and their potential use in electrochemical detection have been investigated. Activated monooxoacylated polyoxotungstates [SiW11O39{Sn(CH2)2CO}]8? and [P2W17O61{Sn(CH2)2CO}]6? have been used to link to a 5′‐NH2 terminated 21‐mer DNA forward primer through amide coupling. The functionalized primer was characterized by using a battery of techniques, including electrophoresis, mass spectrometry, as well as IR and Raman spectroscopy. The functionality of the POM‐labeled primers was demonstrated through hybridization with a surface‐immobilized probe. Finally, the labeled primers were successfully used in the polymerase chain reaction (PCR) and the PCR products were characterized by using electrophoresis. 相似文献