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991.
Hiroshi Kobayashi Toyoko Suzuki Mineho Moritaka Emi Miyanaga Masayoshi Okubo 《Colloid and polymer science》2009,287(3):251-257
Seeded emulsion polymerizations of styrene using polystyrene (PS) seed particles with incorporated nonionic emulsifier were
carried out at 40 and 70 °C to investigate the influence of temperature during the polymerization process including the swelling
step of the seed particles with monomer on the formation of multihollow PS particles. An increase in the temperature during
the polymerization process caused an increase in the rate of coalescence (i.e., the degree of coalescence at any given time)
of the small water domains in the inside. After the coalescence proceeded excessively, the water domains were eventually discharged
from the particles to the medium, resulting in nonhollow particles. The results show that it is important for the preparation
of the multihollow PS particles to control the coalescence of a lot of small water domains inside the seed particles with
the incorporated nonionic emulsifier, and strongly support the formation mechanism previously proposed.
Part CCCXX of the series “Studies on Suspension and Emulsion”. 相似文献
992.
Atsuya Muranaka Dr. Osamu Matsushita Kengo Yoshida Shigeki Mori Dr. Masaaki Suzuki Dr. Taniyuki Furuyama Masanobu Uchiyama Prof. Dr. Atsuhiro Osuka Prof. Dr. Nagao Kobayashi Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(15):3744-3751
Expanded porphyrins : The electronic excited states of two forms of meso‐hexakis(pentafluorophenyl)‐substituted gold(III) hexaphyrin(1.1.1.1.1.1), such as that depicted, have been investigated by density functional calculations and magnetic circular dichroism spectroscopy to assign their low‐energy excited singlet states.
993.
Ryoji Kobori Tomonori Ohba Takaomi Suzuki Taku Iiyama Sumio Ozeki Michio Inagaki Akihiro Nakamura Masato Kawai Hirofumi Kanoh Katsumi Kaneko 《Adsorption》2009,15(2):114-122
N2 adsorption isotherms of molecular sieve carbon were measured at 77 K and 303 K. The Ar adsorption isotherms of molecular
sieve carbon samples were also measured at 303 K. The grand canonical Monte Carlo (GCMC) simulation technique was applied
to calculate the N2 and Ar adsorption isotherms at 303 K using the ultramicropore volume determined by H2O adsorption. The comparative method of experimental and simulated isotherms of supercritical N2 and Ar at 303 K gave the width of the micropore mouth of the molecular sieve carbon, which can be applied to the ultramicropore
width determination for other noncrystalline porous solids. 相似文献
994.
Y. Morisaki K. Saito H. Imoto K. Suzuki Y. Ouchi Y. Chujo 《Polymer Science Series A》2009,51(11-12):1218-1228
Anionic polymerization of triphenylmethyl methacrylate was performed by using P-chiral bisphosphine initiators. According to the optical rotation analysis and circular dichroism measurements, the polymer obtained by using the initiator (S,S)-1,2-bis(boranato(tert-butyl)methylphosphino) ethane exhibited one-handed helical conformation induced by the chirality of phosphorus atoms in the polymer terminal. The enantiomer (R,R)-1,2-bis(boranato(tert-butyl)methylphosphino) ethane gave the opposite one-handed helical polymer. Optically active bisphosphine (S,S)-1,2-bis(boranatomethylphenylphosphino) ethane was employed for the helix-sense-selective polymerization of triphenylmethyl methacrylate in order to obtain the polymer with the same helix sense as the polymer obtained from the initiator (S,S)-1,2-ethane bis(t-butylm-ethylphosphineborane). Further, removal of the coordinated boranes and complexation with platinum(II) on the chiral phosphorus atoms were carried out in order to yield the corresponding polymer-platinum(II) complex without loss of its chiral higher-ordered structure. 相似文献
995.
Suzuki N Hashizume D Yoshida H Tezuka M Ida K Nagashima S Chihara T 《Journal of the American Chemical Society》2009,131(6):2050-2051
Low-valent zirconocene species reacted with 1,1,6,6-tetraalkyl-1,2,3,4,5-hexapentaenes to form both 1-zirconacyclopent-3-ynes and eta2-pi-coordinated complexes according to the alkyl groups (R) and the existence of the neutral ligand (L). Haptotropic interconvertion between these two complexes was observed. It was proposed that double insertion of isocyanide into the Zr-C bond of 1-zirconacyclopent-3-ynes takes place via the isocyanide adduct of the eta2-pi-complex as an intermediate. 相似文献
996.
The unprecedented role of a CuII cryptand in the luminescence properties of a EuIII cryptate complex
Hideki Ohtsu Tomoya Suzuki Hajime Ohtsuka Ayumi Ishii Miki Hasegawa 《Monatshefte für Chemie / Chemical Monthly》2009,25(6):783-787
Abstract
A EuIII cryptate complex constructed from a CuII cryptand with an L tBu ligand, [EuIIICu2II(L tBu)2(NO3)3(MeOH)], and the corresponding CaII and NaI cryptates, [CaIICu2II(L tBu)2(NO3)2(MeOH)2] and [NaICu2II(L tBu)2(Me2CO)](BPh4), have been synthesized and characterized in order to shed light on the essential role of CuII in the luminescence of a EuIII cryptate. The unprecedented role of a CuII cryptand makes it possible to produce lanthanide luminescence in a EuIII cryptate complex and is successfully elucidated by comparison with the corresponding CaII and NaI cryptates. 相似文献997.
Yoshio Kabe Houjin Hachiya Daisuke Shimizu Kazuharu Suzuki Wataru Ando 《Journal of organometallic chemistry》2009,694(13):1988-10153
The addition of silyl diazomethane (1a-d) to fullerene C60 at room temperature provided the mono-adducts, the bis- and tris-adducts of silyl fulleroid (3a-d) in moderate yields. The structures of the silyl fulleroids were characterized by mass spectroscopy, as well as 1H and 13C NMR. The gated 1H NMR and 13C-1H COLOC analyses of 3a-d showed a correlation between the methine proton resonances and three fullerene carbons. These observations, as well as the 1H NMR chemical shifts of the methine protons, suggest a remarkable diastereoselectivity, with the silyl groups located above a five-membered ring. Two transition states of the thermal nitrogen-extrusion of pyrazoline intermediate (2a) were theoretically obtained, the structures of which disclosed that the diastereoselectivity is a consequence of minimization of the repulsive interaction between the silyl groups and the N2 moiety. The bridgehead CC double bond of the silyl fulleroid is thought to be reactive by POAV analyses. The silyl fulleroids (3a,b) were found to react with singlet oxygen to afford the silyl enol ether (9a,b) via 1,3-silyl migration of a diketone (8a,b). This is the first example of 1O2 oxygenation of fulleroids. 相似文献
998.
Kenichi Murata Masato Suzuki Nobuhumi Nakamura Hiroyuki Ohno 《Electrochemistry communications》2009,11(8):1623-1626
The direct electron transfer reaction of fructose dehydrogenase (FDH) from Gluconobacter sp. on alkanethiol-modified silver nanoparticles (AgNPs) was examined using cyclic voltammetry and surface-enhanced resonance Raman scattering (SERRS). Using cyclic voltammetry, catalytic oxidation currents (based on the direct electron transfer reaction of FDH) were observed from a potential of approximately −100 mV (vs. Ag/AgCl, 3 M NaCl) in the presence of d-fructose, without a mediator. A comparison of the SERRS spectra and the resonance Raman spectra of FDH in solution indicated that the heme c site retained its six-coordinated low-spin heme after immobilization. Moreover, SERRS also demonstrated that the heme c of the adsorbed FDH was the electron transfer site within the enzyme. 相似文献
999.
Kenichi Murata Masato Suzuki Kazuki Kajiya Nobuhumi Nakamura Hiroyuki Ohno 《Electrochemistry communications》2009,11(3):668-671
The direct electron transfer reaction of fructose dehydrogenase (FDH) from Gluconobacter sp. on alkanethiol-modified gold nanoparticles (AuNPs) was examined. AuNP-modified electrodes were simply fabricated by depositing citrate-reduced gold nanoparticles onto a gold electrode and carbon fiber paper and then covering the surface with a self-assembled monolayer of alkanethiols. The immobilization of AuNPs provided a large effective surface area for the adsorption of FDH. Catalytic oxidation currents based on the direct electron transfer reaction of FDH were observed from a potential about ?100 mV (vs. Ag/AgCl, 3 M NaCl) in the presence of d-fructose without a mediator. The current density reached as high as 14.3 ± 0.93 mA/cm2 (at +500 mV), which was achieved in the presence of 200 mM d-fructose by immobilization of FDH on 2-mercaptoethanol-modified AuNP/carbon fiber paper electrodes. 相似文献
1000.
C. Li Y. Yamamoto M. Suzuki D. Hirabayashi K. Suzuki 《Journal of Thermal Analysis and Calorimetry》2009,95(3):991-997
TG and DTA experiments were performed to investigate the biomass tar combustion behavior in coexistence of dolomite and mayenite
at two different heating rates as 5 and 15°C min−1. Different reaction kinetic mechanisms with the classical Arrhenius model were used to treat TG data, and showed that the
first-order combustion model fitted the data well. Three stages combustion model was proposed and applied for the calculation
of kinetics parameters successfully. The starting temperature of high temperature combustion stage moved up near 100°C because
of the coexistence catalysts, and the combustion amount of biomass of the stage also improved nearly 10 mass%. By calculation
a uniform trend of decreasing activation energies was observed with the addition of dolomite and mayenite, and also greatly
improved the amount and speed of tar combustion process. 相似文献