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61.
62.
Jun Kawahara Peter Andersson Ersman David Nilsson Kazuya Katoh Yasukazu Nakata Mats Sandberg Marie Nilsson Göran Gustafsson Magnus Berggren 《Journal of Polymer Science.Polymer Physics》2013,51(4):265-271
A flexible electrochromic active matrix addressed display, including 8 × 8 pixels, is demonstrated by using solution processing based on standard printing and coating manufacturing techniques. Each organic electrochromic display (OECD) pixel and its corresponding organic electrochemical transistor (OECT) are located on different sides of the flexible PET substrate. Electronic vias generated through the plastic substrate connects each OECD pixel with one addressing OECT. When comparing this display with actively addressed OECDs with all its components located on the same side, the present approach based on this electronic via substrate provides an enhanced pixel resolution and a relatively more simplified manufacturing process. © 2012 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2012 相似文献
63.
Francęois D. Tropper Fredrik O. Andersson Suoding Cao René Roy 《Journal of carbohydrate chemistry》2013,32(6):741-750
Abstract Peracetylated glycosyl- and glycobiosyl bromides and chlorides 1-4 including acetochloroneuraminic acid 5 were stereoselectively transformed into their corresponding S-glycosyl xanthates 6-10 in high yield (91-98%) under phase transfer catalyzed conditions. The reactions occurred at room temperature using tetrabutylammonium hydrogen sulfate as the catalyst. The substitutions gave complete inversion of configuration and thus proceeded by an SN2 type mechanism. Changing the organic solvent from methylene chloride to ethyl acetate had no detrimental effect on the outcome of the reactions but avoided an undesirable side reaction between the xanthate anion and methylene chloride. 相似文献
64.
Johan R. Johansson Yubo Wang Dr. Mattias P. Eng Prof. Nina Kann Prof. Per Lincoln Dr. Johanna Andersson 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(20):6246-6256
The slow dissociation of DNA threading intercalators makes them interesting as model compounds in the search for new DNA targeting drugs, as there appears to be a correlation between slow dissociation and biological activity. Thus, it would be of great value to understand the mechanisms controlling threading intercalation, and for this purpose we have investigated how the length of the bridging ligand of binuclear ruthenium threading intercalators affects their DNA binding properties. We have synthesised a new binuclear ruthenium threading intercalator with slower dissociation kinetics from ct‐DNA than has ever been observed for any ruthenium complex with any type of DNA, a property that we attribute to the increased distance between the ruthenium centres of the new complex. By comparison with previously studied ruthenium complexes, we further conclude that elongation of the bridging ligand reduces the sensitivity of the threading interaction to DNA flexibility, resulting in a decreased AT selectivity for the new complex. We also find that the length of the bridging ligand affects the enantioselectivity with increasing preference for the ΔΔ enantiomer as the bridging ligand becomes longer. 相似文献
65.
David Wensbo Posaric Anders Andersson Karl-Erik Bergquist Anders Isaksson 《Analytical and bioanalytical chemistry》2014,406(19):4735-4744
Various phosphatidylethanol (PEth) derivatives, the corresponding reversed positional isomers (RPI-PEths), lyso-PEth-16:0, and penta-deuterium-labeled PEth analogs (d5-PEths), were synthesized by enzyme-independent synthetic routes. A general solvent system consisting of a mixture of acetone-d6 and methanol-d4 (97:3; v/v) was found to provide a good solubilizing capacity and excellent hydrogen-1 NMR (1H-NMR) peak resolution of various PEth homologues. Analytical differentiation of PEth from the corresponding RPI-PEth by carbon-13 NMR (13C-NMR) was demonstrated by comparison of the 13C-NMR signals of the carbonyl groups, the allylic positions, and of the β-carbons. An exemplary stable long-term room temperature, DMSO-d6-based, and proton-sensitive quantitative nuclear magnetic resonance (1H-qNMR) independently quantified calibrator comprising PEth-16:0/18:1 for liquid chromatography (tandem) mass spectrometry (LC-MS/MS) analytical applications were prepared by employment of sodium dodecyl sulfate (SDS) as a solubilizing additive. In summary, novel hypothetically occurring PEth derivatives, e.g., RPI-PEths, have been independently synthesized with regio- and stereochemical control. Use of polar organic solvents, e.g., mixtures of acetone-d6 and methanol-d4 or DMSO-d6, improves spectral line shapes as compared to traditional hydrophobic solvents and allow for analytical differentiation between closely related PEth derivatives, as well as LC-MS/MS-independent concentration determination of dissolved single species by employment of 1H-qNMR. Figure
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66.
Rolle Rahikainen Pramila Rijal Tiong Kit Tan Hung‐Jen Wu Anne‐Marie C. Andersson Jordan R. Barrett Thomas A. Bowden Simon J. Draper Alain R. Townsend Mark Howarth 《Angewandte Chemie (International ed. in English)》2021,60(1):321-330
Matching of symmetry at interfaces is a fundamental obstacle in molecular assembly. Virus‐like particles (VLPs) are important vaccine platforms against pathogenic threats, including Covid‐19. However, symmetry mismatch can prohibit vaccine nanoassembly. We established an approach for coupling VLPs to diverse antigen symmetries. SpyCatcher003 enabled efficient VLP conjugation and extreme thermal resilience. Many people had pre‐existing antibodies to SpyTag:SpyCatcher but less to the 003 variants. We coupled the computer‐designed VLP not only to monomers (SARS‐CoV‐2) but also to cyclic dimers (Newcastle disease, Lyme disease), trimers (influenza hemagglutinins), and tetramers (influenza neuraminidases). Even an antigen with dihedral symmetry could be displayed. For the global challenge of influenza, SpyTag‐mediated display of trimer and tetramer antigens strongly induced neutralizing antibodies. SpyCatcher003 conjugation enables nanodisplay of diverse symmetries towards generation of potent vaccines. 相似文献
67.
We have undertaken the molecular imprinting of Leu5-enkephalin, and derivatives related to this endogenous neuropeptide, in highly cross-linked methacrylic acid/ethylene dimethacrylate copolymers. The underivatized enkephalin peptide yielded polymers with poor recognition abilities, since the imprinting of this compound had to be performed using dimethyl sulfoxide, which was found to interfere with the imprint inducement, as the solvent of polymerisation. In order to circumvent this problem, the amino- and carboxy-protected derivatives Boc-Leu5-enkephalin and Leu5-enkephalin anilide, which are soluble in apolar solvents, were investigated as alternative imprint molecules. Both compounds led to polymers which are highly specific for the imprint species. The anilide derivative was shown to be a good substitute for the free peptide since the resultant polymers showed efficient recognition of the parent enkephalin structure. 相似文献
68.
Harry J. Whitlow Margaretha Andersson Mikael Hult Leif Persson Mohamed El Bouanani Mikael Östling Carina Zaring Nils Lundberg David D. Cohen Nick Dytlewski Peter N. Johnston Ian F. Bubb Scott R. Walker Erik Johanson Sture Hogmark P. Anders Ingemarsson 《Mikrochimica acta》1995,120(1-4):171-181
Recoil Spectrometry covers a group of techniques that are very similar to the well known Rutherford backscattering Spectrometry technique, but with the important difference that one measures the recoiling target atom rather than the projectile ion. This makes it possible to determine both the identity of the recoil and its depth of origin from its energy and velocity, using a suitable detector system. The incident ion is typically high-energy (30–100MeV)35C1,81Br or127I. Low concentrations of light elements such as C, O and N can be profiled in a heavy matrix such as Fe or GaAs. Here we present an overview of mass and energy dispersive recoil Spectrometry and illustrate its successful use in some typical applications. 相似文献
69.
Inside Back Cover: The Nature of Activated Non‐classical Hydrogen Bonds: A Case Study on Acetylcholinesterase–Ligand Complexes (Chem. Eur. J. 8/2016) 下载免费PDF全文
70.
Mustafa Barri George K. El Khoury Helge I. Andersson Bjrnar Pettersen 《国际流体数值方法杂志》2010,64(7):777-792
Direct numerical simulation (DNS) has been performed to study the channel flow over a backward‐facing step at a Reynolds number Reb=5600 based on the step height h and the inflow bulk velocity Ub. A dynamic method has been used in order to generate realistic turbulent inflow conditions. The results upstream of the step compared well with the fully developed channel flow. Downstream of the step our results show excellent agreement with experimental data. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献