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21.
Noe Oña Antonio Romero Carmen Assiego Claudia Bello Pierre Vogel M. Soledad Pino-González 《Tetrahedron: Asymmetry》2010,21(17):2092-2099
An approach to the synthesis of polyhydroxyazepane derivatives from sugar-based epoxyamides or epoxyalcohols, in which the total regioselective epoxide opening by nitrogen nucleophiles is the key step, is described. Thus, novel polyhydroxyazepane carboxamides and aminomethyl polyhydroxyazepanes, with potential pharmacological interest, are synthesized from diacetone d-mannose. Configurational assignments of the obtained products were determined. 相似文献
22.
Ahn TK Yoon ZS Hwang IW Lim JK Rhee H Joo T Sim E Kim SK Aratani N Osuka A Kim D 《The journal of physical chemistry. B》2005,109(22):11223-11230
We have investigated the overall excitation energy relaxation dynamics in linear porphyrin arrays as well as the energy transport phenomena by attaching an energy acceptor to one end of a linear porphyrin array by using steady state and time-resolved spectroscopic measurements. We have revealed that the solvation dynamics as well as the conformational dynamics contributes significantly to the energy relaxation processes of linear porphyrin arrays. Consequently, long porphyrin arrays no longer serve as good energy transmission elements in donor-acceptor linked systems due to conformational heterogeneities which provide the non-radiative deactivation channels as energy quenchers. 相似文献
23.
We describe ab initio calculations of doubly strange, S = -2, s-shell hypernuclei (4(LambdaLambda)H, 5LambdaLambda)H, 5(LambdaLambda)He, and 6(LambdaLambda)He) as a first attempt to explore the few-body problem of the full-coupled channel scheme for these systems. The wave function includes LambdaLambda, LambdaSigma, NXi, and SigmaSigma channels. Minnesota NN, D2' YN, and simulated YY potentials based on the Nijmegen hard-core model are used. Bound-state solutions of these systems are obtained. We find that a set of phenomenological B8B8 interactions among the octet baryons in S = 0,-1, and -2 sectors, which is consistent with all of the available experimental binding energies of S = 0,-1, and -2 s-shell (hyper)nuclei, can predict a particle stable bound state of 4(LambdaLambda)H. For 5(LambdaLambda)H and 5(LambdaLambda)He, LambdaN-SigmaN and XiN-LambdaSigma potentials significantly affect the net LambdaLambda-NXi coupling, and a large Xi probability is obtained even for a weaker LambdaLambda-NXi potential. 相似文献
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Rud Wegscheider Noe L. Müller Eduard Chiari 《Monatshefte für Chemie / Chemical Monthly》1908,29(7):713-747
Ohne Zusammenfassung 相似文献
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Kwati Leonard Junichi Kurawaki Katumitu Hayakawa Myint Thein Tun Yoshihumi Kusumoto 《Colloid and polymer science》2009,287(7):773-778
Laser irradiation of copper(II) tetrasulfonated phthalocyanine (CuTsPc) microcrystals in poor organic solvents such as methanol,
2-methyl-2-propanol, ethanol, tetrahydrofuran, and acetone has produced CuTsPc nanoparticles with 15–112 nm in diameter. Field
emission scanning electron microscopy (FESEM) images have shown the formation of CuTsPc nanoparticles in poor organic solvents
used in this work. The mean diameters of CuTsPc nanoparticles obtained from transmission electron microscopy (TEM) images
in methanol, 2-methyl-2-propanol, ethanol, tetrahydrofuran, and acetone were determined to be 26, 36, 35, 86, and 78 nm, respectively.
A correlation between the size of CuTsPc nanoparticles and a solvent polarity could be found in this work. 相似文献
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