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951.
Smirnov M. S. Ovchinnikov O. V. Zvyagin A. I. Tikhomirov S. A. Ponyavina A. N. Povedailo V. A. Binh Nguyen Thanh Minh Pham Hong 《Optics and Spectroscopy》2022,130(3):224-231
Optics and Spectroscopy - The mechanism of the nonlinear optical response of colloidal solutions of Ag2S quantum dots passivated with thioglycolic acid molecules is considered. Appearance of... 相似文献
952.
Journal of Applied Spectroscopy - The grafting of specific functional groups has been drawing attention later as a simple and effective way to modify materials surfaces to induce a particular... 相似文献
953.
Thieu Huy Nguyen 《Archive for Rational Mechanics and Analysis》2014,213(2):689-703
We prove the existence and uniqueness of periodic motions to Stokes and Navier–Stokes flows around a rotating obstacle \({D \subset \mathbb{R}^3}\) with the complement \({\Omega = \mathbb{R}^3 \backslash D}\) being an exterior domain. In our strategy, we show the C b -regularity in time for the mild solutions to linearized equations in the Lorentz space \({L^{3,\infty}(\Omega)}\) (known as weak-L 3 spaces) and prove a Massera-typed Theorem on the existence and uniqueness of periodic mild solutions to the linearized equations in weak-L 3 spaces. We then use the obtained results for such equations and the fixed point argument to prove such results for Navier–Stokes equations around a rotating obstacle. We also show the stability of such periodic solutions. 相似文献
954.
The toxicity and antitumour effect of the ethanol extract of Selaginella tamariscina (STE), a plant widely used in folk medicine, were examined in a mice model. In the single-dose acute toxicity test, an oral administration of 10,000?mg?kg(-1) STE did not cause any lethality. The sub-acute toxicity study showed that the treatment by 250,?1000 and 3000?mg?kg(-1?)day(-1) for 30 continuous days did neither alter the body weights nor the haematological parameters in BALB/c mice. The anticancer effect of STE was evaluated in BALB/c mice inoculated with Lewis lung carcinoma cells. Oral administration of STE could not prevent the tumour formation but provided strong inhibition of tumour growth. 相似文献
955.
An efficient and selective multicomponent oxidative coupling of two different aliphatic primary amines into thioamides by elemental sulfur under solvent-free conditions has been developed. 相似文献
956.
957.
We investigate the molecular and electronic structure and thermochemical properties of the cationic boron clusters B n + with n?=?2–20, using both MO and DFT methods. Several functionals are used along with the MP2, G3, G3B3, G4, and CCSD(T)/CBS methods. The latter is the high accuracy reference. While the TPSS, TPSSh, PW91, PB86, and PBE functionals show results comparable to high-accuracy MO methods, both BLYP and B3LYP functionals are not accurate enough for three-dimensional (3D) structures. A negligible difference is observed between the B3LYP, MP2, and CCSD(T) geometries. A transition between 2D and 3D structures occurs for this series at the B16 +–B19 + sizes. While smaller clusters B n + with n?≤?15 are planar or quasi-planar, a structural competition takes place in the intermediate sizes of B 16–19 + . The B20 + cation has a 3D tubular shape. The standard heats of formation are determined and used to evaluate the cluster stability. The average binding energy tends to increase with increasing size toward a limit. All closed-shell species B n + has an aromatic character, but an enhanced stability is found for B5 + and B13 + whose aromaticity and electron delocalization are analyzed using the LOL technique. 相似文献
958.
Eryazici I Yildirim I Schatz GC Nguyen ST 《Journal of the American Chemical Society》2012,134(17):7450-7458
Detailed experimental and computational studies revealed the important role that hydrophobic interactions play in the aqueous assembly of rigid small molecule-DNA hybrid (rSMDH) building blocks into nanoscale cage and face-to-face (ff) dimeric structures. In aqueous environments, the hydrophobic surfaces of the organic cores in these nanostructures are minimized by interactions with the core in another rSMDHs, with the bases in the attached DNA strands, and/or with the base pairs in the final assembled structures. In the case that the hydrophobic surfaces of the cores could not be properly isolated in the assembly process, an ill-defined network results instead of dimers, even at low concentration of DNA. In contrast, if ff dimers can be formed with good minimization of the exposed hydrophobic surfaces of the cores, they are highly stable structures with enhanced melting temperatures and cooperative melting behavior. 相似文献
959.
960.
In this paper, we study the compactness in L of the semigroup (St)t≥0 of entropy weak solutions to strictly convex scalar conservation laws in one space dimension. The compactness of St for each t > 0 was established by P. D. Lax. Upper estimates for the Kolmogorov e‐entropy of the image of bounded sets in L1 n L∞ through St were given by C. De Lellis and F. Golse. Here we provide lower estimates on this e‐entropy of the same order as the one established by De Lellis and Golse, thus showing that such an e‐entropy is of size ≈ 1/ε. Moreover, we extend these estimates of compactness to the case of convex balance laws. © 2012 Wiley Periodicals, Inc. 相似文献