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1.
As a model for organic ferromagnetism in a one-dimensional system, substituted polyacetylenes are re-considered on the basis of the molecular orbital (MO) and the crystal orbital (CO) methods. The semiempirical MO calculations with configuration interaction for the dimer model show that the exchange interaction on poly[(4-oxyphenyl)acetylene] (1) is negative in spite of Ovchinnikov's prediction, due to the direct interaction between the adjacent pendant spins. On the other hand, it is shown that a polyacetylene chain with phenoxy radicals as pendants on every other active site can become a one-dimensional feromagnet. Moreover, the CO calculations by means of the unrestricted Hartree-Fock method give a theoretical background for the realization of a ground state with macroscopic spin alignment on the improved model chain. 相似文献
2.
Eiichi Hoshino Kazunari Maruta Yasunao Wada Kazuo Mori 《Journal of the American Oil Chemists' Society》1995,72(7):785-791
The interaction of highly purified alkaline protease fromBacillus sp. KSM-K16 with the horny cells of human skin contained in skin grime was directly visualized by electron microscopy. It
became clear that the protease first penetrates the horny cells and then adsorbs, mainly onto the internal structure of the
cells at the initial stage of hydrolysis, and directly hydrolyzes the keratin filaments, though the marginal band surrounding
them retains its original shape. Then, hydrolysate produced from the keratin filaments flows out of the cell, and early in
the hydrolysis process keratin filaments decrease and then disappear, leaving a marginal band, i.e., the cell turns to a hollow
state. As a result, the remaining marginal band loses support from inside the cell, thus promoting cleavage and dispersion.
Until this stage in the protease reaction, the remarkable liberation of hydrolysis products as water-soluble protein does
not occur. 相似文献
3.
4.
Riku Kawasaki Kosuke Kondo Risako Miura Keita Yamana Hinata Isozaki Risako Shimada Shogo Kawamura Hidetoshi Hirano Tomoki Nishimura Naoki Tarutani Kiyofumi Katagiri Alexandra Stubelius Shin-ichi Sawada Yoshihiro Sasaki Kazunari Akiyoshi Atsushi Ikeda 《International journal of molecular sciences》2022,23(9)
Developing photoactivatable theranostic platforms with integrated functionalities of biocompatibility, targeting, imaging contrast, and therapy is a promising approach for cancer diagnosis and therapy. Here, we report a theranostic agent based on a hybrid nanoparticle comprising fullerene nanocrystals and gold nanoparticles (FGNPs) for photoacoustic imaging and photothermal therapy. Compared to gold nanoparticles and fullerene crystals, FGNPs exhibited stronger photoacoustic signals and photothermal heating characteristics by irradiating light with an optimal wavelength. Our studies demonstrated that FGNPs could kill cancer cells due to their photothermal heating characteristics in vitro. Moreover, FGNPs that are accumulated in tumor tissue via the enhanced permeation and retention effect can visualize tumor tissue due to their photoacoustic signal in tumor xenograft model mice. The theranostic agent with FGNPs shows promise for cancer therapy. 相似文献
5.
Stephen Matthew Lyth Huaiyu Shao Jianfeng Liu Kazunari Sasaki Etsuo Akiba 《International Journal of Hydrogen Energy》2014
Hydrogen storage is a crucial technology for the realization of a carbon-neutral society. However, few materials have been able to approach useful hydrogen storage capacity at reasonable temperatures and pressures. Graphene has an extremely high surface-area-to-weight ratio, is strong, cheap, chemically inert, and environmentally benign. As such it may be an ideal substrate for hydrogen storage. Here we present synthesis of graphene foam by combustion of sodium ethoxide. This technique is low-cost, scalable, and results in a three-dimensional graphene network with a surface area of more than 1200 m2/g. It is applied as a hydrogen storage material at liquid nitrogen temperature, with a capacity of 2.1 wt%. 相似文献
6.
Kazunari Nawa 《应用聚合物科学杂志》1996,61(10):1737-1746
The application of advanced polycondensed fused polynuclear aromatic (COPNA) resin to a material for flexible printed wiring boards was studied in this work. To give flexibility to the advanced COPNA resin, a polymer blend technology was introduced. Nylon 6 was selected from the nominated blend polymers with advanced COPNA resin because of sufficient compatibility between the advanced COPNA resin and the amino groups. The polymer blend film, consisting of advanced COPNA resin and nylon 6 prepared at a blend fraction of 50/50 (COPNA/nylon 6), exhibited sufficient flexibility for printed wiring boards, and exhibited attractive properties of Tg at 158°C and a dielectric constant at 3.6. Morphological analysis was also carried out by transmission electron microscopy to the blends. Phase-separated structures were observed in entire systems of fully cured films because of crystallinity of the nylon 6, but sufficient compatibility for practical uses was observed in both the 30/70 and 50/50 systems. The compatibility became poor with an increase of the advanced COPNA resin fraction. © 1996 John Wiley & Sons, Inc. 相似文献
7.
The feasibility of a direct internal reforming (DIR) solid oxide fuel cell (SOFC) running on wet palm‐biodiesel fuel (BDF) was demonstrated. Simultaneous production of H2‐rich syngas and electricity from BDF could be achieved. A power density of 0.32 W cm?2 was obtained at 0.4 A cm?2 and 800 °C under steam to carbon ratio of 3.5. Subsequent durability testing revealed that a DIR‐SOFC running on wet palm‐BDF exhibited a stable voltage of around 0.8 V at 0.2 A cm?2 for more than 1 month with a degradation rate of approximately 15 % / 1000 h. The main cause of the degradation was an increase in the ohmic resistance. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
8.
We investigated the possibility of conjugative plasmid transfer to the predominant bacteria in activated sludge and the factors influencing the transfer frequency in the activated sludge process. We performed conjugative transfers of a self-transmissible, broad-host-range plasmid RP4 from Escherichia coli C600 to activated sludge bacteria by broth mating. Most of the activated sludge bacteria tested could acquire plasmid RP4, although the transfer frequencies varied from 8.8 x 10(-7) to 1.3 x 10(-2) transconjugants per recipient. The transfer frequencies in several strains were similar to, or higher than, that in intraspecific transfer to E. coli HB101. Matings under various environmental conditions showed that factors relevant to physiological activity, such as temperature and nutrient conditions, seemed to affect the transfer frequency. In addition, conjugative transfer was detected even in filtered raw and treated wastewaters. Thus, the predominant activated sludge bacteria seem to have sufficient potential as recipients in conjugative plasmid transfer under the conditions likely to occur in the activated sludge process. Transfer frequency was reduced by agitation in the presence of suspended solid. This may suggest that conjugative plasmid transfer is physically inhibited in aeration tanks. 相似文献
9.
Several hexaaluminate-related materials were prepared via hydrolysis of alkoxide and powder mixing method for high temperature combustion of CH4 and C3H8, in order to investigate the effect of the concentration of the fuels, O2 and H2O on NOx emission and combustion characteristics. Among the hexaaluminate catalysts, Sr0.8La0.2MnAl11O19− prepared by the alkoxide method exhibited the highest activity for methane combustion and low NOx emission capability. NOx emission at 1500 °C was increased linearly with O2 concentration, whereas water vapor addition decreased NOx emission in CH4 combustion over the Sr0.8La0.2MnAl11O19− catalyst. In the catalytic combustion of C3H8 over the Sr0.8La0.2MnAl11O19− catalyst, the amount of NOx emitted was raised in the temperature range between 1000 and 1500 °C when the C3H8 concentration increased from 1 to 2 vol.%. It was found that NOx emission in this temperature range was reduced effectively by adding water vapor. 相似文献
10.
Ryuta Shigefuku Hideaki Takahashi Hiroyasu Nakano Tsunamasa Watanabe Kotaro Matsunaga Nobuyuki Matsumoto Masaki Kato Ryo Morita Yousuke Michikawa Tomohiro Tamura Tetsuya Hiraishi Nobuhiro Hattori Yohei Noguchi Kazunari Nakahara Hiroki Ikeda Toshiya Ishii Chiaki Okuse Shigeru Sase Fumio Itoh Michihiro Suzuki 《International journal of molecular sciences》2016,17(9)
The progression of chronic liver disease differs by etiology. The aim of this study was to elucidate the difference in disease progression between chronic hepatitis C (CHC) and nonalcoholic fatty liver disease (NAFLD) by means of fibrosis markers, liver function, and hepatic tissue blood flow (TBF). Xenon computed tomography (Xe-CT) was performed in 139 patients with NAFLD and 152 patients with CHC (including liver cirrhosis (LC)). The cutoff values for fibrosis markers were compared between NAFLD and CHC, and correlations between hepatic TBF and liver function tests were examined at each fibrosis stage. The cutoff values for detection of the advanced fibrosis stage were lower in NAFLD than in CHC. Although portal venous TBF (PVTBF) correlated with liver function tests, PVTBF in initial LC caused by nonalcoholic steatohepatitis (NASH-LC) was significantly lower than that in hepatitis C virus (C-LC) (p = 0.014). Conversely, the liver function tests in NASH-LC were higher than those in C-LC (p < 0.05). It is important to recognize the difference between NAFLD and CHC. We concluded that changes in hepatic blood flow occurred during the earliest stage of hepatic fibrosis in patients with NAFLD; therefore, patients with NAFLD need to be followed carefully. 相似文献