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11.
Mahalingam V Naccache R Vetrone F Capobianco JA 《Chemical communications (Cambridge, England)》2011,47(12):3481-3483
The intensity of high energy UV and blue upconverted emissions of Tm(3+) ions in Tm(3+)/Yb(3+) co-doped LiYF(4) colloidal nanocrystals was selectively reduced compared to the NIR emission at 802 nm. This was achieved by doping a small amount of Dy(3+) ions into the host matrix. 相似文献
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Karaman R 《Journal of computer-aided molecular design》2010,24(12):961-970
DFT calculation results for intramolecular proton transfer reactions in Kirby’s enzyme models 1–7 reveal that the reaction rate is quite responsive to geometric disposition, especially to distance between the two reactive
centers, r
GM, and the angle of attack, α (the hydrogen bonding angle). Hence, the study on the systems reported herein could provide a
good basis for designing aza nucleoside prodrug systems that are less hydrophilic than their parental drugs and can be used,
in different dosage forms, to release the parent drug in a controlled manner. For example, based on the calculated log EM,
the cleavage process for prodrug 1ProD is predicted to be about 1010 times faster than that for prodrug 7ProD and about 104 times faster than prodrug 3ProD: rate
1ProD
> rate
3ProD
> rate
7ProD
. Hence, the rate by which the prodrug releases the aza nucleoside drug can be determined according to the structural features
of the linker (Kirby’s enzyme model). 相似文献
14.
In this work, we are interested to obtain some result of existence and nonex- istence of positive weak solution for the following p-Laplacian system
{-△piui=λifi(u1,^…,um),inΩ, i=1,...,m, ui=0,
on δΩ,Vi=1,…,m,
where △piz = div(|△z|^pi-2△Z), Pi ≥ 1,λi,1 ≤ i ≤ m are a positive parameter, and Ω is a bounded domain in IR^N with smooth boundary δΩ. The proof of the main results is based to the method of sub-supersolutions. 相似文献
{-△piui=λifi(u1,^…,um),inΩ, i=1,...,m, ui=0,
on δΩ,Vi=1,…,m,
where △piz = div(|△z|^pi-2△Z), Pi ≥ 1,λi,1 ≤ i ≤ m are a positive parameter, and Ω is a bounded domain in IR^N with smooth boundary δΩ. The proof of the main results is based to the method of sub-supersolutions. 相似文献
15.
Loutfy H. Madkour Amera M. Hassanein Mohamed M. Ghoneim Safwat A. Eid 《Monatshefte für Chemie / Chemical Monthly》2001,132(2):245-258
Summary. The inhibition of corrosion of iron in 2 M nitric acid and 2 M sulfuric acid solutions by substituted phenylhydantoin, thiohydantoin, and dithiohydantoin compounds was measured using thermometric,
weight loss, and polarization methods. The three methods gave consistent results. The polarization curves indicated that the
hydantoin compounds act as mixed-type inhibitors. The adsorption of the inhibitors were found to obey the Temkin adsorption isotherm. The higher inhibition efficiency of the additives in nitric with respect to sulfuric acid solution may
be attributed to the reduced formation of soluble quaternary nitrogen salts in nitric acid medium, favouring adsorption of
the parent additive on the metal surface. The obtained results indicate that the corrosion rate of iron in both acids increases
with increasing temperature, both in absence and presence of the tested inhibitors. Kinetic-thermodynamic model functions
and Temkin isotherm data are compared and discussed. The synergistic effect of halide anions on the inhibition efficiency of the hydantoin
compounds was also investigated.
Received June 5, 2000. Accepted (revised) September 13, 2000 相似文献
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A PMR analytical procedure is described for the quantitation of camphor and parachlorophenol in camphorated parachlorophenol. The method is simple, rapid and accurate with standard deviations of ±1.13, ± 1.01 for camphor and ± 0.62, ± 0.89 for parachlorophenol, in standard mixtures and in camphorated parachlorophenol, respectively. The PMR spectrum, in addition, provides a very specific means for identification of camphor and parachlorophenol. 相似文献
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20.
Numerical modeling of multiphase flow generally requires a special procedure at the solid wall in order to be consistent with Young's law for static contact angles. The standard approach in the lattice Boltzmann method, which consists of imposing fictive densities at the solid lattice sites, is shown to be deficient for this task. Indeed, fictive mass transfer along the boundary could happen and potentially spoil the numerical results. In particular, when the contact angle is less than 90 degrees, the deficiencies of the standard model are major. Various videos that demonstrate this behavior are provided (Supporting Information). A new approach is proposed and consists of directly imposing the contact angle at the boundaries in much the same way as Dirichlet boundary conditions are generally imposed. The proposed method is able to retrieve analytical solutions for static contact angles in the case of straight and curved boundaries even when variable density and viscosity ratios between the phases are considered. Although the proposed wetting boundary condition is shown to significantly improve the numerical results for one particular class of lattice Boltzmann model, it is believed that other lattice Boltzmann multiphase schemes could also benefit from the underlying ideas of the proposed method. The proposed algorithm is two‐dimensional, and the D2Q9 lattice is used. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献