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11.
Shibata T Ito S Doe M Tanaka R Hashimoto H Kinoshita I Yano S Nishioka T 《Dalton transactions (Cambridge, England : 2003)》2011,40(25):6778-6784
Nickel complexes having acetylated glucopyranosyl group incorporated N-heterocyclic carbene (NHC) ligands with methyl or benzyl groups as an N-substituent exhibit two kinds of dynamic behaviours in solution (1)H NMR spectroscopy. One of the dynamic behaviours is attributed to the anti- and syn-rotamers, which occur by the rotation of the unsymmetrical NHC ligands around the axes of the Ni-C bonds. The other is attributed to the diastereomers of the syn-rotamers, which occur by opposite rotation of the imidazolylidene rings and the chiral carbohydrate group incorporated into the NHC ligands. Crystallographic analysis of the nickel complex having the NHC ligand with acetylated glucopyranosyl and benzyl groups as N-substituents showed CH-π interaction between the glucopyranosyl unit of each NHC ligand and the phenyl ring of the other NHC ligand in the complex in the solid state. 相似文献
12.
Aharmim B Ahmed SN Amsbaugh JF Anthony AE Banar J Barros N Beier EW Bellerive A Beltran B Bergevin M Biller SD Boudjemline K Boulay MG Bowles TJ Browne MC Bullard TV Burritt TH Cai B Chan YD Chauhan D Chen M Cleveland BT Cox-Mobrand GA Currat CA Dai X Deng H Detwiler J DiMarco M Doe PJ Doucas G Drouin PL Duba CA Duncan FA Dunford M Earle ED Elliott SR Evans HC Ewan GT Farine J Fergani H Fleurot F Ford RJ Formaggio JA Fowler MM Gagnon N Germani JV Goldschmidt A Goon JT Graham K Guillian E 《Physical review letters》2008,101(11):111301
The Sudbury Neutrino Observatory (SNO) used an array of 3He proportional counters to measure the rate of neutral-current interactions in heavy water and precisely determined the total active (nu_x) 8B solar neutrino flux. This technique is independent of previous methods employed by SNO. The total flux is found to be 5.54_-0.31;+0.33(stat)-0.34+0.36(syst)x10(6) cm(-2) s(-1), in agreement with previous measurements and standard solar models. A global analysis of solar and reactor neutrino results yields Deltam2=7.59_-0.21;+0.19x10(-5) eV2 and theta=34.4_-1.2;+1.3 degrees. The uncertainty on the mixing angle has been reduced from SNO's previous results. 相似文献
13.
14.
Daisuke Takano Matsumi Doe Yoshiki Morimoto Takamasa Kinoshita Kazuo Yoshihara 《Journal of heterocyclic chemistry》1999,36(1):221-224
The first synthesis of (-)-meridinol and (-)-3-epimeridinol was accomplished from (S)-malic acid. This synthesis unambiguously established the absolute stereochemistry of meridinol. 相似文献
15.
Limit on flavor-changing neutral currents from a measurement of neutrino-electron elastic scattering
16.
Osako T Tachi Y Doe M Shiro M Ohkubo K Fukuzumi S Itoh S 《Chemistry (Weinheim an der Bergstrasse, Germany)》2004,10(1):237-246
Crystal structures of the copper(I) complexes 1(X), 2, and 3 of a series of tridentate ligands L1(X), L2, and L3, respectively (L1(X): p-substituted derivatives of N,N-bis[2-(2-pyridyl)ethyl]-2-phenylethylamine; X=H, Me, OMe, Cl, NO(2); L2: N,N-bis[2-(2-pyridyl)ethyl]-2-methyl-2-phenylethylamine; L3: N,N-bis[2-(2-pyridyl)ethyl]-2,2-diphenylethylamine) were solved to demonstrate that all the copper(I) complexes involve an eta(2) copper-arene interaction with the phenyl ring of the ligand sidearm. The Cu(I) ion in each complex has a distorted tetrahedral geometry consisting of the three nitrogen atoms (one tertiary amine nitrogen atom and two pyridine nitrogen atoms) and C(1)-C(2) of the phenyl ring of ligand sidearm, whereby the Cu-C distances of the copper-arene interaction significantly depend on the para substituents. The existence of the copper-arene interaction in a nonpolar organic solvent (CH(2)Cl(2)) was demonstrated by the observation of an intense MLCT band around 290 nm, and the magnitude of the interaction was evaluated by detailed analysis of the (1)H and (13)C NMR spectra and the redox potentials E(1/2) of the copper ion, as well as by means of the ligand-exchange reaction between the phenyl ring and CH(3)CN as an external ligand. The thermodynamic parameters DeltaH(o) and DeltaS(o) for the ligand-exchange reaction with CH(3)CN afforded a quantitative measure for the energy difference of the copper-arene interaction in the series of copper(I) complexes. Density functional studies indicated that the copper(I)-arene interaction mainly consists of the interaction between the d(z(2) ) orbital of Cu(I) and a pi orbital of the phenyl ring. The copper(I) complexes 1(X) reacted with O(2) at -80 degrees C in CH(2)Cl(2) to give the corresponding (micro-eta(2):eta(2)-peroxo)dicopper(II) complexes 4, the formation rates k(obs) of which were significantly retarded by stronger d-pi interaction, while complexes 2 and 3, which exhibit the strongest d-pi interaction showed significantly lower reactivity toward O(2) under the same experimental conditions. Thus, the d-pi interaction has been demonstrated for the first time to affect the copper(I)-dioxygen reactivity, and represents a new aspect of ligand effects in copper(I)-dioxygen chemistry. 相似文献
17.
Pankaj?SehgalEmail author Hidekazu?Doe Manu?Sharma Daniel?E.?Otzen 《Colloid and polymer science》2005,283(11):1219-1225
The synergistic behavior of sodiumdodecylsulfate (SDS) and 1,2-diheptanoyl-sn-glycero-3-phosphocholine (DHPC) binary mixtures
has been studied with interfacial and pyrene fluorescence(I
1/ I
3) intensity measurements. From the interfacial data, the interfacial parameters; the maximum surface excess (Γmax), or the minimum area per molecule (A
min), and the surface pressure at the critical micellar concentration (πcmc) have been evaluated. The cmc value has been used for evaluating the free energies of micellization (ΔG
o
m). The mixed micelle formation was evaluated with the help of the Clint equation. The SDS plus DHPC mixed micelles showed
negative departure from ideality indicating synergistic interactions between the unlike components. The quantitative analysis
of mixed micelle, mixed monolayer and the composition of the mixed micelle was carried out with the help of regular solution
approximation. The interaction parameters, β and βσ, in the mixed micelle as well as in the mixed monolayer, respectively showed negative values indicating synergistic behavior
of SDS and DHPC molecules. 相似文献
18.
Tokutaro Ogata Misae Doe Aya Matsubara Eri Torii Chiaki Nishiura Arisa Nishiuchi Yusuke Kobayashi Tetsutaro Kimachi 《Tetrahedron》2014
The oxidative intramolecular cyclization of 3-hydroxyalkyl-1,2,4-trimethoxynaphthalenes was investigated. A series of 1,2-naphthoquinone fused cyclic ethers were synthesized directly from 3-hydroxyalkyl-1,2,4-trimethoxynaphthalenes by exposure to diammonium cerium (IV) nitrate. To understand the reaction mechanism, the intramolecular cyclization of 3-hydroxyalkyl-naphthoquinones that were formed as reaction intermediates was also examined. The results suggested that the reaction proceeds by a stepwise oxidation–cyclization mechanism. Using this methodology, five-step synthesis of rhinacanthone was achieved with high yield. 相似文献
19.
Tetsuo Iwagawa Miho MiyazakiHiroaki Okamura Munehiro NakataniMatsumi Doe Kaoru Takemura 《Tetrahedron letters》2003,44(12):2533-2535
Three novel bis(indole) alkaloids with an unprecedented skeleton have been isolated from a stony coral, Tubastraea sp. These indoles could biogenetically be derived from two molecules of aplysinopsin via a Diels-Alder reaction. 相似文献
20.
D. Sinclair A. L. Carter D. Kessler E. D. Earle P. Jagam J. J. Simpson R. C. Allen H. H. Chen P. J. Doe E. D. Hallman W. F. Davidson R. S. Storey A. B. McDonald G. T. Ewan H. -B. Mak B. C. Robertson 《Il Nuovo Cimento C》1986,9(2):308-317
Summary The proposal to build a heavy-water Čerenkov detector deep underground is discussed. The main physics objectives are to measure
the8B solar neutrino flux, to identify neutrino oscillations and to watch for gravitational collapse. The measurements of the
sources of background and the optical properties of heavy water, which are necessary to prove the feasibility of the detector,
are reported. The present status of the project is indicated.
Riassunto Si discute il progetto di costruire un rivelatore Čerenkov ad acqua pesante a grande profondità. Gli obiettivi fisici principali sono quelli di misurare il flusso di neutrini solati di8B, d'identificare le oscillazioni neutriniche e di osservare il collasso gravitazionale. Si riportano le misure delle sorgenti di background e le proprietà ottiche dell'acqua pesante, che sono necessarie per provare la fattibilità del rivelatore. Si indica lo stato attuale del progetto.
Резюме Обсуждается преложение о строительстве черенковского детектора на тяжелойводе. Основные физические задачи—измерение потока8B солнечных нейтрино, идентификация нейтринных осцилляций и наблюдение гравитационного коллапса Сообщаются результаты измерений источников фона и оптических свойств тяжелой воды, необходимые для вьшолнения этого детектора. Описывается состояние проекта в настоящее время.相似文献