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351.
Anna Zahoranová Mirko Černák Miloslav Štefečka Hans-Erich Wagner 《Czechoslovak Journal of Physics》1999,49(12):1721-1735
Current wave forms of initial stages of discharge formation in a short negative point-to-plane gap have been measured with
a nanosecond time resolution in hydrogen at pressures (12.5–76) kPa and for various overvoltages and cathode point radii.
The measurements revealed the existence of a stepped form of negative corona current pulses in hydrogen. To test existing
models for negative corona pulse formation, effects of changing cathode secondary electron emission were studied using copper
and brass cathodes coated by CuI and graphite. It is concluded that a negative corona pulse is associated with the ignition
of a cathode-directed streamer in the vicinity of the cathode. We report what we believe are the first experimental observations
of non-Trichel oscillations of negative corona current with a frequency of (1–10) MHz.
This work was supported by the Scientific Grant Agency of the Ministry of Education and Academy of Sciences of Slovak Republic
(Project No. 1/5190/98). 相似文献
352.
353.
The cyclic chromatic number χc(G) of a 2‐connected plane graph G is the minimum number of colors in an assigment of colors to the vertices of G such that, for every face‐bounding cycle f of G, the vertices of f have different colors. Plummer and Toft proved that, for a 3‐connected plane graph G, under the assumption Δ*(G) ≥ 42, where Δ*(G) is the size of a largest face of G, it holds that χc(G) ≤ Δ*(G) + 4. They conjectured that, if G is a 3‐connected plane graph, then χc>(G) ≤ Δ*(G) + 2. In the article the conjecture is proved for Δ*(G) ≥ 24. © 1999 John Wiley & Sons, Inc. J Graph Theory 30: 177–189, 1999 相似文献
354.
Mazzapioda Lucia Sgambetterra Mirko Tsurumaki Akiko Navarra Maria Assunta 《Journal of Solid State Electrochemistry》2022,26(1):17-27
Journal of Solid State Electrochemistry - A series of sulfated aluminum oxides (S-Al2O3), investigated as an electrolyte additive in Nafion membranes, was synthesized via three different methods:... 相似文献
355.
Numerical simulations are performed for multiphase jets in crossflow. The flow solver uses an Eulerian/Lagrangian approach. Turbulence in the gas phase is modeled in the framework of large eddy simulation. The dispersed phase is handled using Lagrangian particle tracking. The model assumptions of solvers for Lagrangian particle tracking are critically assessed for typical flow conditions of spray jets in crossflow. The droplets are assumed to be spherical and isolated. It is shown that several model assumptions are apparently inconsistent in larger portions of the flow field. Firstly, average Weber numbers can be so large that the model assumption to regard droplets as spherical is questionable, not only near the nozzle, but also in the far-field. Secondly, the average droplet spacing can be so low that droplets directly interact with each other, again also in the far-field. Thirdly, the average Stokes numbers in the jet region can be so large that the phase coupling between the dispersed and continuous phase is weak. Some remedies to these deficiencies are proposed. 相似文献
356.
357.
Dr. Stefano Carli Dr. Giulia Fioravanti Dr. Andrea Armirotti Dr. Francesca Ciarpella Dr. Mirko Prato Dr. Giuliana Ottonello Dr. Marco Salerno Dr. Alice Scarpellini Dr. Daniela Perrone Dr. Elena Marchesi Dr. Davide Ricci Prof. Luciano Fadiga 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(9):2322-2329
Localized drug delivery represents one of the most challenging uses of systems based on conductive polymer films. Typically, anionic drugs are incorporated within conductive polymers through electrostatic interaction with the positively charged polymer. Following this approach, the synthetic glucocorticoid dexamethasone phosphate is often delivered from neural probes to reduce the inflammation of the surrounding tissue. In light of the recent literature on the neuroprotective and anti-inflammatory properties of tauroursodeoxycholic acid (TUDCA), for the first time, this natural bile acid was incorporated within poly(3,4-ethylenedioxythiophene) (PEDOT). The new material, PEDOT—TUDCA, efficiently promoted an electrochemically controlled delivery of the drug, while preserving optimal electrochemical properties. Moreover, the low cytotoxicity observed with viability assays, makes PEDOT–TUDCA a good candidate for prolonging the time span of chronic neural recording brain implants. 相似文献
358.
We consider planar skew Brownian motion (BM) across pre-fractal Koch interfaces ?Ω n and moving on \(\overline {{\Omega }^{n}} \cup {\Sigma }^{n}= {\Omega }^{n}_{\varepsilon }\) where Σ n is a suitable neighbourhood of ?Ω n . We study the asymptotic behaviour of the corresponding multiplicative functionals when thickness of Σ n and skewness coefficients vanish with different rates. Thus, we provide a probabilistic framework for studying diffusions across semi-permeable pre-fractal (and fractal) layers and the asymptotic analysis concerning the insulating fractal layer case. 相似文献
359.
Todd Cowen Mirko Busato Kal Karim Sergey A. Piletsky 《Macromolecular rapid communications》2016,37(24):2011-2016
Molecularly imprinted polymer (MIP) synthetic receptors have proposed and applied applications in chemical extraction, sensors, assays, catalysis, targeted drug delivery, and direct inhibition of harmful chemicals and pathogens. However, they rely heavily on effective design for success. An algorithm has been written which mimics radical polymerization atomistically, accounting for chemical and spatial discrimination, hybridization, and geometric optimization. Synthetic ephedrine receptors were synthesized in silico to demonstrate the accuracy of the algorithm in reproducing polymers structures at the atomic level. Comparative analysis in the design of a synthetic ephedrine receptor demonstrates that the new method can effectively identify affinity trends and binding site selectivities where commonly used alternative methods cannot. This new method is believed to generate the most realistic models of MIPs thus produced. This suggests that the algorithm could be a powerful new tool in the design and analysis of various polymers, including MIPs, with significant implications in areas of biotechnology, biomimetics, and the materials sciences more generally.
360.