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101.
Kiem PV Tri MD Tuong le VD Tung NH Hanh NN Quang TH Cuong NX Minh CV Choi EM Kim YH 《Chemical & pharmaceutical bulletin》2008,56(9):1270-1275
Two new phenyl glycosides, mangliesides A and B (1, 2), a new ionol glycoside, manglieside C (3), two new lignan glycosides, mangliesides D and E (4, 5), were isolated from the leaves of Manglietia phuthoensis, along with two known lignans, 3-methoxymagnolol (6) and obovatol (7). Their structures were established by means of 1D and 2D NMR, electrospray ionization (ESI)-MS and HR-ESI-MS experiments. Among them, compounds 2 and 5 significantly (p<0.05) increased the growth and differentiation of osteoblastic MC3T3-E1 cells in vitro. 相似文献
102.
The permeability of poly(butylene terephthalate) was examined for He, Ne, Ar and CO2 at the temperature range of 293–338 K and an upstream pressure to 1,2 bar. The energies of activation of permeation and diffusion in case of Ne, Ar and CO2 are higher above glass transition temperature than below, while they are nearly constant in case of He. The dependence of temperature of solubility coefficients does not change at the glass transition temperature. 相似文献
103.
In this paper, we use a simple discrete dynamical model to study integer partitions and their lattice. The set of reachable configurations of the model, with the order induced by the transition rule defined on it, is the lattice of all partitions of a positive integer, equipped with a dominance ordering. We first explain how this lattice can be constructed by an algorithm in linear time with respect to its size by showing that it has a self-similar structure. Then, we define a natural extension of the model to infinity, which we compare with the Young lattice. Using a self-similar tree, we obtain an encoding of the obtained lattice which makes it possible to enumerate easily and efficiently all the partitions of a given integer. This approach also gives a recursive formula for the number of partitions of an integer, and some informations on special sets of partitions, such as length bounded partitions. 相似文献
104.
Hoa V. Phan Pradip Chakraborty Meimei Chen Yitzi M. Calm Dr. Kirill Kovnir Lawrence K. Keniley Jr. Jordan M. Hoyt Elisabeth S. Knowles Dr. Céline Besnard Prof. Mark W. Meisel Prof. Andreas Hauser Prof. Catalina Achim Prof. Michael Shatruk 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(49):15805-15815
Three iron(II) complexes, [Fe(TPMA)(BIM)](ClO4)2?0.5H2O ( 1 ), [Fe(TPMA)(XBIM)](ClO4)2 ( 2 ), and [Fe(TPMA)(XBBIM)](ClO4)2 ?0.75CH3OH ( 3 ), were prepared by reactions of FeII perchlorate and the corresponding ligands (TPMA=tris(2‐pyridylmethyl)amine, BIM=2,2′‐biimidazole, XBIM=1,1′‐(α,α′‐o‐xylyl)‐2,2′‐biimidazole, XBBIM=1,1′‐(α,α′‐o‐xylyl)‐2,2′‐bibenzimidazole). The compounds were investigated by a combination of X‐ray crystallography, magnetic and photomagnetic measurements, and Mössbauer and optical absorption spectroscopy. Complex 1 exhibits a gradual spin crossover (SCO) with T1/2=190 K, whereas 2 exhibits an abrupt SCO with approximately 7 K thermal hysteresis (T1/2=196 K on cooling and 203 K on heating). Complex 3 is in the high‐spin state in the 2–300 K range. The difference in the magnetic behavior was traced to differences between the inter‐ and intramolecular interactions in 1 and 2 . The crystal packing of 2 features a hierarchy of intermolecular interactions that result in increased cooperativity and abruptness of the spin transition. In 3 , steric repulsion between H atoms of one of the pyridyl substituents of TPMA and one of the benzene rings of XBBIM results in a strong distortion of the FeII coordination environment, which stabilizes the high‐spin state of the complex. Both 1 and 2 exhibit a photoinduced low‐spin to high‐spin transition (LIESST effect) at 5 K. The difference in the character of intermolecular interactions of 1 and 2 also manifests in the kinetics of the decay of the photoinduced high‐spin state. For 1 , the decay rate constant follows the single‐exponential law, whereas for 2 it is a stretched exponential, reflecting the hierarchical nature of intermolecular contacts. The structural parameters of the photoinduced high‐spin state at 50 K are similar to those determined for the high‐spin state at 295 K. This study shows that N‐alkylation of BIM has a negligible effect on the ligand field strength. Therefore, the combination of TPMA and BIM offers a promising ligand platform for the design of functionalized SCO complexes. 相似文献
105.
The paper describes a parallel algorithm for computing an n-dimensional Delaunay tessellation using a divide-conquer strategy. Its implementation (using MPI library for C) in the case
n = 2, relied on restricted areas to discard non-Delaunay edges, is executed easily on PC clusters. We shows that the convexity
is a crucial factor of efficiency of the parallel implementation over the corresponding sequential one. 相似文献
106.
Bao Nguyen Xuan Duy Khanh Phan Quoc Tung Nguyen Minh 《Set-Valued and Variational Analysis》2022,30(2):465-486
Set-Valued and Variational Analysis - We aim to establish Karush-Kuhn-Tucker multiplier rules involving higher-order complementarity slackness under Hölder metric subregularity. These rules... 相似文献
107.
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109.
Convex underestimators of a polynomial on a box. Given a non convex polynomial ${fin mathbb{R}[{rm x}]}$ and a box ${{rm B}subset mathbb{R}^n}$ , we construct a sequence of convex polynomials ${(f_{dk})subset mathbb{R}[{rm x}]}$ , which converges in a strong sense to the “best” (convex and degree-d) polynomial underestimator ${f^{*}_{d}}$ of f. Indeed, ${f^{*}_{d}}$ minimizes the L 1-norm ${Vert f-gVert_1}$ on B, over all convex degree-d polynomial underestimators g of f. On a sample of problems with non convex f, we then compare the lower bounds obtained by minimizing the convex underestimator of f computed as above and computed via the popular α BB method and some of its other refinements. In most of all examples we obtain significantly better results even with the smallest value of k. 相似文献
110.
Phan Van Thien 《代数通讯》2013,41(10):3704-3715
We will give a formula to compute the regularity index of s + 2 fat points not lying on a linear (s ? 1)-space in ? n , s ≤ n (Theorem 3.4). Our result generalizes a formula to compute the regularity index of fat points in general position in ? n ([3], Corollary 8). Our result also shows that the Segre bound is attained by s + 2 points not lying on a linear (s ? 1)-space. 相似文献