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61.
The aim of this paper is to control the rate of convergence for central limit theorems of sojourn times of Gaussian fields in both cases: the fixed and the moving level. Our main tools are the Malliavin calculus and the Stein method, developed by Nualart, Peccati and Nourdin. We also extend some results of Berman to the multidimensional case. 相似文献
62.
63.
Regioselective hydrolysis of cocaine led, according to the reaction conditions, either to benzoylecgonine or to ecgonine methyl ester. Acylation with benzoylecgonine was readily achieved when benzotriazolyloxytrisdimethylamino-phosphonium (BOP) was used as a coupling agent. 相似文献
64.
In the copolymerization of vinyl acetate (A) with either vinyl chloride (C) or vinylidene chloride (V), an internal transfer (backbiting) reaction—of the C- or V-ended radi-cals on an antepenultimate A unit—is proposed to be responsible for the deviation of the copolymerization kinetics from the Lewis and Mayo theory. The deviations disappear if A is replaced by isopropenylacetate [Ip], Then one gets, for the Ip -C copolymerization. rI p =0.35 and :rc=2.4, and for I -V copolymerization, rI p=0.13 and rv=5.9. The internal transfer reaction causes the formation of branches which may be evidenced by NMR analysis of constant composition suspension A-C copolymers. A kinetic scheme is proposed and the corresponding reactivity ratios derived rA=0.29, rc=1.60, r=0.3 (radical resulting from the transfer reaction), and kT=1500 (rate constant of the transfer reaction at 50°C). The distribution of branches is calculated together with the sequence distribution functions for the .A. or Cunits. 相似文献
65.
66.
H. T. Hoang A. A. Sertsova S. I. Marakulin E. N. Subcheva M. P. Zaitseva E. V. Yurtov 《Russian Journal of Inorganic Chemistry》2018,63(11):1414-1418
MgO@SiO2 core–shell nanoparticles were manufactured, and a synthetic protocol was developed to prepare MgO nanoparticles where the SiO2 shell thickness was less than 10 nm. The influence of synthesis parameters on the formation of MgO@SiO2 nanoparticles was studied. The fact of a SiO2 shell being formed on the MgO surface was established and the sizes of the thus-prepared MgO@SiO2 nanoparticles were determined by TEM and Fourier-transform IR spectroscopy. 相似文献
67.
Redox‐responsive core cross‐linked micelles of poly(ethylene oxide)‐b‐poly(furfuryl methacrylate) by Diels‐Alder reaction for doxorubicin release 下载免费PDF全文
Cuong M. Q. Le Hai Ha Pham Thi Xuan Thang Cao Gun‐Do Kim Chul‐Woong Oh Kwon Taek Lim 《Journal of polymer science. Part A, Polymer chemistry》2016,54(23):3741-3750
Redox‐responsive core cross‐linked (CCL) micelles of poly(ethylene oxide)‐b‐poly(furfuryl methacrylate) (PEO‐b‐PFMA) block copolymers were prepared by the Diels‐Alder click‐type reaction. First, the PEO‐b‐PFMA amphiphilic block copolymer was synthesized by the reversible addition‐fragmentation chain transfer polymerization. The hydrophobic blocks of PFMA were employed to encapsulate the doxorubicin (DOX) drug, and they were cross‐linked using dithiobismaleimidoethane at 60 °C without any catalyst. Under physiological circumstance, the CCL micelles demonstrated the enhanced structural stability of the micelles, whereas dissociation of the micelles took place rapidly through the breaking of disulfide bonds in the cross‐linking linkages under reduction environment. The core‐cross‐linked micelles showed fine spherical distribution with hydrodynamic diameter of 68 ± 2.9 nm. The in vitro drug release profiles presented a slight release of DOX at pH 7.4, while a significant release of DOX was observed at pH 5.0 in the presence of 1,4‐dithiothreitol. MTT assays demonstrated that the block copolymer did not have any practically cytotoxicity against the normal HEK293 cell line while DOX‐loaded CCL micelles exhibited a high antitumor activity towards HepG2 cells. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 3741–3750 相似文献
68.
Truong Son Pham Katalin Gönczi György Kardos Krisztina Süle László Hegedűs Mihály Kállay Miklós Kubinyi Pál Szabó Imre Petneházy László Tőke Zsuzsa Jászay 《Tetrahedron: Asymmetry》2013,24(24):1605-1614
Several cinchona based squaramide catalysts were applied to the asymmetric Michael addition of α-nitroethylphosphonates to acrylic acid aryl esters, resulting in high yields and enantioselectivities. The absolute configuration of one of the quaternary α-nitrophosphonate adducts was deduced from its experimental and calculated CD spectra. The adducts were reduced to their cyclic aminophosphonates by catalytic hydrogenation. 相似文献
69.
Energy management in buildings is addressed in this paper. The energetic impact of buildings in the current energetic context
is first depicted. Then the studied optimization problem is defined as the optimal management of production and consumption
activities in houses. A scheduling problem is identified to adjust the energy consumption to both the energy cost and the
inhabitant’s comfort. The available flexibilities of the services provided by domestic appliances are used to compute optimal
energy plans. These flexibilities are associated to time windows or heating storage abilities. A constraints formulation of
the energy allocation problem is given. A derived mixed linear program is used to solve this problem. The energy consumption
in houses is very dependent to uncertain data such as weather forecasts and inhabitants’ activities. Parametric uncertainties
are introduced in the home energy management problem in order to provide robust energy allocation. Robust linear programming
is implemented. Event related uncertainties are also addressed through stochastic programming in order to take into account
the inhabitant’s activities. A scenario based approach is implemented to face this robust optimization problem. 相似文献
70.
Ly Dieu Ha Poul Erik Hansen Fritz Duus Hung Dinh Pham Lien‐Hoa D. Nguyen 《Magnetic resonance in chemistry : MRC》2012,50(3):242-245
Four new prenylated depsidones, oliveridepsidones A–D, were isolated from the bark of Garcinia oliveri collected in Vietnam. Their structures were elucidated using mainly NMR techniques (1H and 13C NMR, HMQC, HMBC and NOE experiments). Copyright © 2012 John Wiley & Sons, Ltd. 相似文献