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71.
T. Matsumoto S. Nagaoka K. Ikemoto M. Mitsui M. Ara H. Tada A. Nakajima 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2009,52(1-3):99-102
A hexadecyl monolayer covalently attached to Si(111) surfaces (C16–Si(111)) was prepared at 200 ○C from 1-hexadecene. Formation of the monolayer was characterized by water contact angle measurement, attenuated total reflection infrared (ATR-IR) spectroscopy, and X-ray photoelectron spectroscopy (XPS). Gas phase synthesized vanadium (V)-benzene (Bz) 1:2 (VBz2) sandwich clusters were size-selectively deposited onto the C16–Si(111) substrate thus prepared and an oxidized Si substrate. Investigation of the resultant clusters was implemented by thermal desorption spectroscopy (TDS). About 30 K increase in threshold desorption temperature of the landed clusters was observed on going from the oxidized Si to the C16–Si(111) substrate, a result indicating that the clusters are more strongly bound to the C16–Si(111) than to the oxidized Si. This result was explained by the penetration of the landed clusters into the hexadecyl monolayer. 相似文献
72.
Masayuki Kurokuzu Shinji Kitao Yasuhiro Kobayashi Makina Saito Ryo Masuda Takaya Mitsui Yoshitaka Yoda Makoto Seto 《Hyperfine Interactions》2014,226(1-3):687-691
The Mössbauer spectra of the 35.49 keV excited state of 125Te were observed in the energy domain using synchrotron radiation for the first time. The obtained isomer shifts and Debye temperature agree with previous experiments. These results show that this method will be applicable to various compounds. 相似文献
73.
Hidenori Otsuka Taketomo Sanbai Daisuke Matsukuma Yusuke Ikenaga 《Colloid and polymer science》2014,292(2):291-300
We have newly synthesized amphiphilic block copolymers composed of hydrophilic poly(ethylene glycol) (PEG) and hydrophobic pyridine segments (PEG-b-Py). Chain transfer agent-terminated PEG was subsequently chain-extended with 3-(4-pyridyl)-propyl acrylate to obtain PEG-b-Py by reversible additional-fragmentation chain transfer polymerization. Particularly, the effect of varying molecular weight (Mn) of PEG (Mn?=?2,000 and 5,000) and Py in the block copolymers was investigated in terms of critical micelle concentration, pyrene solubilization, micelle size distribution, and association number per micelle. Based on the amphiphilic balance, PEG-b-Pys formed core-shell type polymer micelle. The association number of PEG2k-b-Py was higher than that of PEG5k-b-Py, suggesting the degree of phase separation strongly depended on PEG Mn. Furthermore, the adsorption of PEG-b-Py copolymer onto silica nanoparticles as dispersant was studied to estimate the effect of PEG Mn in the copolymers and their solubility in the medium on the adsorption. Adsorbed density of PEG2k-b-Py copolymer onto silica nanoparticle was higher than that of PEG5k-b-Py, which was significantly correlated with the degree of phase separation. Furthermore, the adsorbed amount of copolymer increased with the increase in ionic strength due to the reduced solubility of PEG in the buffer solution. The resultant dispersion stability was highly correlated with the graft density of copolymer onto silica surface. However, the stability of PEG2k-b-Py coated particles was lower than that with PEG5k-b-Py, this is attributed to the relatively thin layer of PEG at the silica surface, which cannot provide the system with sufficient steric stabilization as the salt concentration increases. These fundamental investigations for the surface modification of the nanoparticle provide the insight into the highly stable colloidal dispersion, particularly in the physiological condition with high ionic strength. 相似文献
74.
Kentaro Mitsui 《Mathematische Zeitschrift》2014,276(1-2):237-242
We give a new method to construct unirational surfaces which may be applied to the following question posed by Zariski in his studies on unirational surfaces. Is any Zariski surface with geometric genus zero rational? Our main result is a negative answer to this question in any characteristic case. 相似文献
75.
Takaya Mitsui Ryo Masuda Naohisa Hirao Ko Mibu Makoto Seto 《Hyperfine Interactions》2012,205(1-3):97-100
Formation of LaFeO3 nanoparticles obtained from thermal decomposition of organometallic precursors was investigated as a function of the heat-treatment temperature. The precursors heat-treated below 300°C were amorphous, but above 350°C a single-phase of nanocrystalline LaFeO3 was formed. The LaFeO3 nanoparticles showed the superparamagnetic behavior in both magnetization and M?ssbauer measurements. With increasing heat-treatment temperature, the crystallite size of LaFeO3 nanoparticles was gradually increased. The quadrupole splitting and isomer shift of paramagnetic doublet pattern were affected by the growth of LaFeO3 particles. 相似文献
76.
77.
N Mitsui T Noro M Kuroyanagi T Miyase K Umehara A Ueno 《Chemical & pharmaceutical bulletin》1989,37(2):363-366
Three strong alkaloidal monoamine oxidase (MAO) inhibitors, quinine (1), cinchonicinol ([ 1S,3'R,4'R]-3-(3-ethenyl-4-piperidinyl)-1-(4-quinolinyl)-1-propanol) (2) and cinchonaminone ([ 3'R,4'S]-2-[2-(3-ethenyl-4-piperidinyl)-acetyl]-1H-indole-3-ethanol) (3), were isolated from Cinchonae Cortex (Cinchona succirubra Pav., Rubiaceae). The structures of 2 and 3 were elucidated on the bases of spectral data and chemical evidence, and 3 is a new alkaloid. The inhibitory effects on MAO of 1, 2, 3 and related alkaloids were assayed. The type of inhibition by 1 with respect to benzylamine as a substrate was competitive. 相似文献
78.
Hiroshi Mitsui Sueo Machi Miyuki Hagiwara Tsutomu Kagiya 《Journal of polymer science. Part A, Polymer chemistry》1967,5(5):1073-1082
The relation between the gaseous products and the reaction conditions such as pressure, temperature, and dose rate in the γ-radiation-induced polymerization of ethylene was studied. The main gaseous products were hydrogen and acetylene, and the amounts of these products increased linearly with reaction time, monomer density, and dose rate, while they were independent of reaction temperature. The ratio of rate of formation of hydrogen to acetylene was about one-half. Further, it was found that the number of moles of polymer chain formed was almost equal to that of acetylene at room temperature. An initiation mechanism in which both hydrogen and acetylene are formed is proposed. The equation which is derived on the basis of the initiation mechanism is shown to be in good accordance with the experimental results. 相似文献
79.
80.
Hemolytic and its protective activity of ginseng saponins 总被引:3,自引:0,他引:3
T Namba M Yoshizaki T Tominori K Kobashi K Mitsui 《Chemical & pharmaceutical bulletin》1973,21(2):459-461