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81.
Venzo de Sabbata C. Sivaram L. Garcia de Andrade 《International Journal of Theoretical Physics》1993,32(9):1523-1530
We study electrodynamics in Einstein-Cartan space-time, that is, in space-time with torsion, and show an analogy with the Chern-Simons gauge-invariant massive electrodynamics. In our case, however, there is no arbitrary parameter, the torsionQ playing the role of the Chern-Simons parameter. This leads to bounds on the photon mass, charge, and torsion coupling. 相似文献
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4H‐cyclopenta[2,1‐b:3,4‐b′]dithiophen‐4‐one (CPDTO) homopolymer with side chains on every other CPDTO
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Jianyuan Sun Swaminathan Venkatesan Ashish Dubey Qiquan Qiao Cheng Zhang 《Journal of polymer science. Part A, Polymer chemistry》2017,55(6):1077-1085
A soluble 4H‐cyclopenta[2,1‐b ;3,4‐b ′]dithiophene‐4‐one (CPDTO)‐based polymer (C6‐PCPDTO) has been synthesized from two monomers derived from nonalkylated CPDTO and didodecyl CPDTO (C12‐CPDTO). Proton NMR, thermal analysis, UV–vis absorption, cyclic voltammetry, and XRD are used to characterize the polymer in solution and film. The new polymer has an optical bandgap of 1.28 eV in film, and has strong interchain interaction in chloroform solutions. The polymer contains a significant amount of homocoupled segments. The regular segments and homocoupled CPDTO segments render the polymer highly aggregating in solution. The non‐planar homocoupled C12‐CPDTO segments prevent the polymer from forming regular π‐stacks, resulting in a low SCLC hole mobility (3.88 × 10?7 cm2V?1s?1). CV experiments show that C6‐PCPDTO is stable in its oxidized and reduced states. Solar cell devices were fabricated from C6‐PCPDTO2 :PC60BM blends of different weight ratios. High PC60BM loading (80% or greater) was required for the devices to show measurable efficiency, indicating that the limited π‐stacking of the polymer is not sufficient to cause effective phase separation. Further development of synthetic method is still needed to eliminate structural defects so that long‐range ordered pi‐stacking can be realized in the polymer for these applications. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55 , 1077–1085 相似文献
85.
Kavya Swaminathan Jeffrey C. Dyason Andrea Maggioni Mark von Itzstein Kevin M. Downard 《Analytical and bioanalytical chemistry》2013,405(20):6563-6572
The binding of a natural anthocyanin to influenza neuraminidase has been studied employing mass spectrometry and molecular docking. Derived from a black elderberry extract, cyanidin-3-sambubiocide has been found to be a potent inhibitor of sialidase activity. This study reveals the molecular basis for its activity for the first time. The anthocyanin is shown by parallel experimental and computational approaches to bind in the so-called 430-cavity in the vicinity of neuraminidase residues 356–364 and 395–432. Since this antiviral compound binds remote from Asp 151 and Glu 119, two residues known to regulate neuraminidase resistance, it provides the potential for the development of a new class of antivirals against the influenza virus without this susceptibility. 相似文献
86.
Peter G. Jones Henning Hopf Cornelia Mlynek Vijay Narayanan Swaminathan 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(12):o723-o725
In benzene‐1,2,3‐tricarbonitrile, C9H3N3, the packing of the two independent molecules is three‐dimensional and complex, involving inter alia bifurcated (C—H)2...N systems from neighbouring CH groups. In [2.2]paracyclophane‐4,5,12,13‐tetracarbonitrile, C20H12N4, the [2.2]paracyclophane systems display the usual distortions, namely lengthened C—C bonds and widened sp3 angles in the bridges, narrow angles in the six‐membered rings at the bridgehead atoms, and flattened boat conformations of the rings. The molecules are linked by a series of C—H...N interactions to form layers parallel to the ab plane. 相似文献
87.
Kwong-Kit Choi Carlos Monroy Venkataraman Swaminathan Theodor Tamir Ming Leung John Devitt David Forrai Darrel Endres 《Infrared Physics & Technology》2007,50(2-3):124-135
Previously, we demonstrated a large format 1024 × 1024 corrugated quantum well infrared photodetector focal plane array (C-QWIP FPA). The FPA has a cutoff at 8.6 μm and is BLIP at 76 K with f/1.8 optics. The pixel had a shallow trapezoidal geometry that simplified processing but limited the quantum efficiency QE. In this paper, we will present two approaches to achieve a larger QE for the C-QWIPs. The first approach increases the size of the corrugations for more active volume and adopts a nearly triangular pixel geometry for larger light reflecting surfaces. With these improvements, QE is predicted to be about 35% for a pair of inclined sidewalls, which is more than twice the previous value. The second approach is to use Fabry–Perot resonant oscillations inside the corrugated cavities to enhance the vertical electric field strength. With this approach, a larger QE of 50% can be achieved within certain spectral regions without using either very thick active layers or anti-reflection coatings. The former approach has been adopted to produce two FPAs, and the preliminary experimental results will be discussed. In this paper, we also describe using voltage tunable detector materials to achieve multi-color capability for these FPAs. 相似文献
88.
Creep damage behaviour of water quenched 5Cr–0.5Mo steel has been studied using magnetic Barkhausen emissions (MBE) technique. The results were compared with the materials having same composition but used in service for 15 years to demonstrate the potentiality of the magnetic technique for in-situ evaluation of extent of creep damage of components. The rms voltage of magnetic Barkhausen signal for the virgin sample decreased at the initial stage of the expended creep life where new carbides are formed. As soon as the growth of the carbides took place at the expense of the smaller ones, MBE voltage started increasing due to the decrease of pinning density. However, in case of 15 years of service exposed sample, growth of carbides already took place and hence MBE voltage increased even during the initial stage of laboratory creep testing. As soon as the void started forming in the samples (both for virgin and service exposed one), the rate of increase of MBE voltage started decreasing. The formations of such cavities were observed through SEM micrograph analysis. 相似文献
89.
N.A.K. Doan S. Bansude K. Osawa Y. Minamoto T. Lu J.H. Chen N. Swaminathan 《Proceedings of the Combustion Institute》2021,38(4):5415-5422
Direct Numerical Simulations (DNS) data of Moderate or Intense Low-oxygen Dilution (MILD) combustion are analysed to identify the contributions of the autoignition and flame modes. This is performed using an extended Chemical Explosive Mode Analysis (CEMA) which accounts for diffusion effects allowing it to discriminate between deflagration and autoignition. This analysis indicates that in premixed MILD combustion conditions, the main combustion mode is ignition for all dilution and turbulence levels and for the two reactant temperature conditions considered. In non-premixed conditions, the preponderance of the ignition mode was observed to depend on the axial location and mixture fraction stratification. With a large mixture fraction lengthscale, ignition is more preponderant in the early part of the domain while the deflagrative mode increases further downstream. On the other hand, when the mixture fraction lengthscale is small, sequential autoignition is observed. Finally, the various combustion modes are observed to correlate strongly with mixture fraction where lean mixtures are more likely to autoignite while stoichiometric and rich mixtures are more likely to react as deflagrative structures. 相似文献
90.
Selvam Kaliyamoorthy Sreedhar Bojja Swaminathan Meenakshisundaram 《Research on Chemical Intermediates》2022,48(3):1309-1309
Research on Chemical Intermediates - This article has been retracted. Please see the Retraction Notice for more detail: https://doi.org/10.1007/s11164-020-04374-7 相似文献