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121.
Background
Recently, we showed a selective enhancement in corticospinal excitability when participants actively discriminated raised 2-D symbols with the index finger. This extra-facilitation likely reflected activation in the premotor and dorsal prefrontal cortices modulating motor cortical activity during attention to haptic sensing. However, this parieto-frontal network appears to be finely modulated depending upon whether haptic sensing is directed towards material or geometric properties. To examine this issue, we contrasted changes in corticospinal excitability when young adults (n = 18) were engaged in either a roughness discrimination on two gratings with different spatial periods, or a 2-D pattern discrimination of the relative offset in the alignment of a row of small circles in the upward or downward direction. 相似文献122.
J.-F. Daigle Y. Kamali M. Chateauneuf G. Tremblay F. Théberge J. Dubois G. Roy S. L. Chin 《Applied physics. B, Lasers and optics》2009,97(3):701-713
A method involving a closed loop adaptive optic system is investigated as a tool to significantly enhance the collected optical
emissions, for remote sensing applications involving ultrafast laser filamentation. The technique combines beam expansion
and geometrical focusing, assisted by an adaptive optics system to correct the wavefront aberrations. Targets, such as a gaseous
mixture of air and hydrocarbons, solid lead and airborne clouds of contaminated aqueous aerosols, were remotely probed with
filaments generated at distances up to 118 m after the focusing beam expander. The integrated backscattered signals collected
by the detection system (15–28 m from the filaments) were increased up to a factor of 7, for atmospheric N2 and solid lead, when the wavefronts were corrected by the adaptive optic system. Moreover, an extrapolation based on a simplified
version of the LIDAR equation showed that the adaptive optic system improved the detection distance for N2 molecular fluorescence, from 45 m for uncorrected wavefronts to 125 m for corrected. 相似文献
123.
Using the evolution history of the universe, one can make constraint on the parameter space of dynamic dark energy models. We discuss two different parameterized dark energy models. Our results further restrict the combined constraints obtained from supernova and the first-year Wilkinson-microwave-anisotropy-probe observations. From the allowed parameter space, it is found that our universe will experience an eternal acceleration. We also estimate the bound on the physically relevant regions both in the re-inflationary and inflationary phases. 相似文献
124.
Solid‐Phase Parallel Synthesis of Functionalised Medium‐to‐Large Cyclic Peptidomimetics through Three‐Component Coupling Driven by Aziridine Aldehyde Dimers
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Dr. Adam P. Treder Dr. Jennifer L. Hickey Marie‐Claude J. Tremblay Dr. Serge Zaretsky Dr. Conor C. G. Scully Dr. John Mancuso Annie Doucet Prof. Andrei K. Yudin Prof. Eric Marsault 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(25):9249-9255
The first solid‐phase parallel synthesis of macrocyclic peptides using three‐component coupling driven by aziridine aldehyde dimers is described. The method supports the synthesis of 9‐ to 18‐membered aziridine‐containing macrocycles, which are then functionalized by nucleophilic opening of the aziridine ring. This constitutes a robust approach for the rapid parallel synthesis of macrocyclic peptides. 相似文献
125.
ORBKIT: A modular python toolbox for cross‐platform postprocessing of quantum chemical wavefunction data
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Gunter Hermann Vincent Pohl Jean Christophe Tremblay Beate Paulus Hans‐Christian Hege Axel Schild 《Journal of computational chemistry》2016,37(16):1511-1520
ORBKIT is a toolbox for postprocessing electronic structure calculations based on a highly modular and portable Python architecture. The program allows computing a multitude of electronic properties of molecular systems on arbitrary spatial grids from the basis set representation of its electronic wavefunction, as well as several grid‐independent properties. The required data can be extracted directly from the standard output of a large number of quantum chemistry programs. ORBKIT can be used as a standalone program to determine standard quantities, for example, the electron density, molecular orbitals, and derivatives thereof. The cornerstone of ORBKIT is its modular structure. The existing basic functions can be arranged in an individual way and can be easily extended by user‐written modules to determine any other derived quantity. ORBKIT offers multiple output formats that can be processed by common visualization tools (VMD, Molden, etc.). Additionally, ORBKIT possesses routines to order molecular orbitals computed at different nuclear configurations according to their electronic character and to interpolate the wavefunction between these configurations. The program is open‐source under GNU‐LGPLv3 license and freely available at https://github.com/orbkit/orbkit/ . This article provides an overview of ORBKIT with particular focus on its capabilities and applicability, and includes several example calculations. © 2016 Wiley Periodicals, Inc. 相似文献
126.
M.G. Townsend J.R. Gosselin R.J. Tremblay L.G. Ripley D.W. Carson W.B. Muir 《Journal of Physics and Chemistry of Solids》1977,38(10):1153-1159
Magnetic susceptibilities and Mössbauer spectra recorded at temperatures between 4° and 300°K show that the low temperature form of Cu5FeS4, bornite, orders magnetically at 76±2°K. At a lower temperature 8°K a second magnetic phase transition occurs. The Mössbauer spectra suggest that there is significant partial disordering of cations and vacancies in tetrahedral holes of the face-centred cubic sulphur lattice. Thermoelectric power measurements indicate that bornite is a p-type semiconductor.For a three dimensional magnetic superexchange interaction between Fe(III) atoms a small super-transferred spin density would be required on intermediate Cu(I) atoms. 相似文献
127.
An axicon is used to focus a CO2-TEA laser pulse in a high pressure preionized mixture of He-N2. An amplified stimulated emission (ASE) effect at 337.1 nm (N2) is obtained. The dependence of inversion population on the electron density is shown. Also presented is the electron temperature as a function of the CO2 pulse intensity for different mixtures of He-N2. 相似文献
128.
129.
The present report describes the design and application of a dual sprayer system for high-throughput proteome analysis. This system comprises parallel solid-phase extraction cartridges used for preconcentration and desalting of proteolytic digests prior to nanoelectrospray mass spectrometry analyses. Tryptic peptides from in-gel digest of protein bands/spots are first adsorbed on styrene divinyl benzene membrane and subsequently eluted with a short plug of organic buffer prior to infusion to the mass spectrometer at a flow rate of typically 500 nL/min. Tryptic peptide eluting from the membrane are analyzed by the mass spectrometer by moving in turn each sprayer in front of the sampling orifice. Sequential injection, preconcentration and analyses of tryptic digests are typically achieved with a throughput of up to 3.5 min/sample and a detection limit of approximately 8-80 fmol per injection. Replicate injections of peptide mixtures indicated that reproducibility of peak areas ranged from relative standard deviations (RSD) of 1.1% to 4.5%. The application of this device is demonstrated for digests of gel-isolated proteins obtained from sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) separation of rat liver plasma membrane and from two-dimensional gel electrophoresis of total cell lysate extracts from human prostatic cancer cell. 相似文献
130.
(-)-Menthone, an inexpensive chiral auxiliary, was used to prepare both enantiomers of alpha-amino acids, amino alcohols, or oxazolidinones. The sequence includes the S(N)2' displacement by a cuprate reagent and a Curtius rearrangement as key steps. 相似文献