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131.
Tomoya Ohno Kazunori Numakura Hidenobu Itoh Hisao Suzuki Takeshi Matsuda 《Advanced Powder Technology》2011,22(3):390-395
This paper describes control of the coating layer thickness and the crystallite size of the core–shell hybrid particles by controlling the process parameter. The core–shell hybrid particles were prepared using liquid phase deposition (LPD). We confirmed that the homogeneous coating was attained from the result of the zeta potential and the transmission electron microscope (TEM) observation. Furthermore, the coating layer microstructure was estimated using Brunauer–Emmett–Teller (BET) method. The obtained coating layer of titania was estimated using the band gap energy. Results indicate that the blue shift of the band gap energy signifies that the physical property of the hybrid particles was controlled by the coating layer thickness and the crystallite size, which are determined by the processing parameters. 相似文献
132.
Matsuda S Liu H Kato S Hashimoto K Nakanishi S 《Environmental science & technology》2011,45(23):10163-10169
Geobacter sulfurreducens is a gram-negative δ-proteobacterium that is capable of transferring respiratory electrons to solid-state extracellular acceptors, including anodes, via abundant c-type cytochromes expressed in the outer membrane. As extracellular electron transfer (EET) to solid-state acceptors can proceed without the addition of exogenous mediators, this microbe has attracted significant attention with respect to energy conversion between electrical and chemical energy. Here, we revealed that clear redox peaks were present in the whole-cell cyclic voltammogram of G. sulfurreducens at around -0.15 V vs Ag|AgCl when tin-doped In(2)O(3) (ITO) glass was used as an anode. Interestingly, the EET current decreased in the potential region more positive than the midpoint potential (E(m)) of the redox peak. Thus, EET of anode-respiring G. sulfurreducens cells exhibited a negative Faradaic resistance (NFR) characteristic at the E(m) of the redox peak, in contrast to general electrochemical systems where the Faradaic current typically increases with increasing overpotential. 相似文献
133.
Taguchi T Rao Z Ito M Matsuda M 《Journal of materials science. Materials in medicine》2011,22(10):2357-2363
We developed a poly(ethylene glycol) (PEG) derivative with oleyl groups, so-called “cell adhesive”, for the promotion of human
hepatocellular carcinoma HepG2 cell spheroids. Our approach was based on crosslinking of the cell membrane with a cell adhesive
via a hydrophobic interaction. A cell adhesive, PEG derivative with hydrophobic oleyl groups at both ends was synthesized
and characterized. HepG2 spheroids formed when the adhesive was added to cell suspensions. The size of the spheroids increased
with time in culture. In addition, Ammonia elimination of HepG2 spheroid with cell adhesive was 3.4 times higher than that
without cell adhesive. Furthermore, albumin secretion from HeG2 spheroids grown with the cell adhesive for 7 days was 3.3
times that from HepG2 spheroids grown without cell adhesive. Fluorescence microscopy showed greater albumin staining in spheroids
grown with cell adhesive compared with spheroids grown without adhesive. This cell adhesive may be useful not only for single
type of cells but also for multi types of cells to form artificial organs. This cell adhesive will be a key material for liver
tissue engineering when it will apply to primary hepatocytes. 相似文献
134.
Hae-Seok Lee Hiroshi Okada Akihiro Wakahara Akira Yoshida Takeshi Ohshima Hisayoshi Itoh Shirou Kawakita Mitsuru Imaizumi Sumio Matsuda 《Solar Energy Materials & Solar Cells》2003,75(1-2):57-63
High-energy proton irradiation (380 keV and 1 MeV) on the electrical properties of CuInSe2 (CIS) thin films has been investigated. The samples were epitaxially grown on GaAs (0 0 1) substrates by Radio Frequency sputtering. As the proton fluence exceeded 1×1013 cm−2, the carrier concentration and mobility of the CIS thin films were decreased. The carrier removal rate with proton fluence was estimated to be about 1000 cm−1. The electrical properties of CIS thin films before and after irradiation were studied between 80 and 300 K. From the temperature dependence of the carrier concentration in CIS thin films, we found ND=9.5×1016 cm−3, NA=3.7×1016 cm−3 and ED=21 meV from the fitting to the experimental data on the basis of the charge balance equation. After irradiation, a defect level was created, and NT=1×1017 cm−3 for a fluence of 3×1013 cm−2, NT=5.7×1017 cm−3 for a fluence of 1×1014 cm−2 and ET=95 meV were also obtained from the same fitting. The new defect, which acted as an electron trap, was due to proton irradiation, and the defect density was increased with proton fluence. 相似文献
135.
The fabrication process for a-Si:H solar cells with p–i–n structure contains a problem of damage to the SnO2 substrate particularly at higher process temperatures. We have reported that the suppression of darkening and wide optical gap (Eopt) are obtained by using SiH2Cl2 instead of SiH4 as a source gas (Mater. Res. Soc. Symp. Proc. 609 (2000), in press). In this paper, p-type a-Si:H:(Cl) was investigated. Comparable Eopt and dark conductivity (σdark) to those of conventional a-SiC:H were obtained. Solar cells using this a-Si:H:(Cl) show higher current density (Jsc) and higher collection efficiency in all wavelength regions as compared to a p-layer not using chlorine processes. The newly developed p-layer has been applied to solar cells with p–i–n structure fabricated at higher substrate temperatures (Ts). Although the a-Si:H material deposited at higher substrate temperatures has been reported as being more stable against light soaking (21st IEEE PVSC Proceeding, Florida, USA, 1990, p. 1656), the high temperature processing is difficult to apply to the a-Si:H p–i–n structure because of the significant darkening of SnO2 at higher Ts. With an a-Si:H:(Cl) buffer layer, a-Si:H solar cells can be fabricated at higher Ts (300°C) with reasonable cell performance. The best stabilized efficiency was 7.5% obtained at a Ts of 250°C. 相似文献
136.
Yoshikawa M Seki H Inoue K Matsuda K Tanahashi Y Sako H Nanen Y Kato M Kimoto T 《Applied spectroscopy》2011,65(5):543-548
We used Fourier transform infrared (FT-IR) spectroscopy to characterize silicon dioxide (SiO(2)) films on a 4H-SiC(0001) Si face. We found that the peak frequency of the transverse optical (TO) phonon in SiO(2) films grown on a 4H-SiC substrate agrees well with that in SiO(2) films grown on a Si substrate, whereas the peak frequency of the longitudinal optical (LO) phonon in SiO(2) films on a 4H-SiC substrate is red-shifted by approximately 50 cm(-1) relative to that in SiO(2) films on a Si substrate. We concluded that this red-shift of the LO phonon is mainly caused by a change in inhomogeneity due to a decrease in density in the SiO(2) films. Furthermore, cathodoluminescence (CL) spectroscopy results indicated that the channel mobility of the SiC metal-oxide-semiconductor field-effect transistor (MOSFET) decreases roughly in proportion to the increase in the intensity of the CL peak at 460 and 490 nm, which is attributed to the increase in the number of oxygen vacancy centers (OVCs). FT-IR and CL spectroscopies provide us with a large amount of data on OVCs in the SiO(2) films on a 4H-SiC substrate. 相似文献
137.
Ryota Masumoto Ken-ichi Ueno Hirofumi Matsuda Ryuji Nomura Yuichi Okuda 《Journal of Low Temperature Physics》2011,162(5-6):399-406
Crystallization of 4He in aerogels of 90 and 96% porosities shows a dynamical phase transition at around 600 mK due to the competition between thermal fluctuation and disorder: crystals grow via creep at high temperatures and via avalanche at low temperatures. In a very high porosity 99.5% aerogel, however, the transition had not been observed in our previous publication (Nomura et al. in Phys. Rev. Lett. 101:175703, 2008). We improved the spatial resolution of the video image and found that the 99.5% aerogel did have the transition at around 200 mK, which is much lower than those of the lower porosities. The avalanche size is significantly smaller in the 99.5% aerogel. The reduction in the transition temperature and avalanche size may be the consequence of weaker disorder for the crystallization in the very high porosity aerogel. 相似文献
138.
The case of a patient who presented with a ruptured aneurysm of the brachial artery and type I neurofibromatosis is presented. Angiography revealed a ruptured aneurysm of the brachial artery in the middle of the upper arm. Repair of the artery with autogenous vein grafting was impossible due to the extremely brittle brachial artery and accompanying veins. The blood supply distal to the aneurysm was secured by collaterals, and the aneurysm, including a relatively long portion of the brachial artery and veins adjacent to the aneurysm, was resected. The patient died of massive hemorrhage from the subclavian artery of the involved side 9 days postoperatively. Histological and immunohistological examinations of the tissues involved in the ruptured aneurysm were conducted. The resected brachial artery and veins were surrounded by hypertrophied tissue which tested positive for S-100 protein and negative for desmin and action. These findings suggest that the origin of the proliferating tissue was not mesodermal dysplasia, but neurofibroma occurring near or in the vessels. A ruptured aneurysm in a patient with neurofibromatosis should not be treated with reconstruction of the vessels. The treatment of choice is surgical or endovascular occlusion of the vessels involved. 相似文献
139.
X Wang AA Thant K Machida Y Hiraiwa H Iwata S Matsuda M Hamaguchi 《Canadian Metallurgical Quarterly》1998,12(5):1097-1101
We found that ectopic expression of N-cadherin in 3Y1 caused tight association of cells and, thereby, substantially suppressed cell growth. N-cadherin expression inhibited neither tyrosine phosphorylation of cellular proteins, GTP uptake onto Ras, nor activation of MAP kinase, suggesting that it does not directly interfere the Ras-MAP kinase pathway. However, co-expression of N-cadherin with dominant negative Ras, S17N Ras, showed synergestic growth inhibitory effect, suggesting that N-cadherin signaling antagonizes the Ras-MAP kinase signaling. In addition, we found that N-cadherin yielded cell-cycle arrest at G0/G1 phase. These results strongly suggest that N-cadherin cell adhesion machinery works as a negative controller of cell cycle in 3Y1 and this growth suppressive function of cadherin is distinct from the epithelial morphogenetic function. 相似文献
140.
For the study of the acidic character of layered perovskite oxide, HLaNb2O7 (HLa), the intercalation of water and alcohols was performed and further the HLa was used of dehydration of 1- and 2-butanol as a test reaction. The acidic properties of the HLa was greatly affected by the irreversible water in the interlayer removed in the temperature range of 350°C
00°C. In the presence of water, the intercalation of hydrophilic nalcohols having carbon number below 5 occurred. Dehydration activity of 2-butanol was higher than 1-butanol and produced only n-butenes. On the other hand, butenes and n-butylaldehyde were produced in the reaction of 1-butanol, especially the formation of the latter was predominant at the lower temperature as 200°C
50°C. With raising the heat-treatment temperature of the catalyst its acidity decreased and was almost lost at 500°C. However, the selectivity to n-butylaldehyde increased, indicating that the acidity did not concern to the nbutylaldehyde formation. The reaction behaviors of 1-and 2-butanol on the HLa catalyst were discussed. 相似文献