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121.
122.
Novel chitosan‐based materials with a higher fatty acid glycidyl as the chemically modified agent were synthesized and the adsorption ability of the resulting polymers has been evaluated for typical anionic and cationic dyes. The successful modification was confirmed by the infrared spectroscopic measurements. As the degree of substitution was decreased, the adsorption ability of the chemically modified chitosans for anionic dyes at the higher dye concentration was increased, and the modified chitosans with a lower degree of substitution showed a higher adsorption ability than that of an activated carbon at the higher dye concentration. For cationic dyes, the chemically modified chitosan showed a good adsorption power, especially when the adsorption power was evaluated by the flow methods. The improved adsorption ability of a chemically modified chitosan material was also confirmed by comparing it with that of a crosslinked chitosan material. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 2423–2428, 2005 相似文献
123.
Satoshi Hiraoka Takeshi Fujii Hideyuki Takakura Yoshihiro Hamakawa 《Solar Energy Materials & Solar Cells》2003,75(3-4):781-786
One-year field experience of an 80 kW PV system on a rooftop of the ROHM Memorial VLSI Research Center at the Ritsumeikan University is reported. All kinds of live technology available materials, c-Si, poly Si and a-Si solar cells are installed on the three tilt angles of 26.5° south, horizontal and north 26.5°. Systematic PV performances have been measured from the beginning of June 2000 to the end of May 2001. Measurements were made mainly on DC output power from four kinds of PV arrays; c-Si south side, a-Si of horizontal and poly Si, a-Si north side. It has been shown from analyses of monthly data on each material that almost 70% of with that in the south side in the annual average. In summer a-Si module yields the maximum output power normalized to 1 kWp. On the contrary c-Si module shows larger output in winter. Some other unique results are demonstrated and discussed. 相似文献
124.
Er3+-doped SiO2 glasses with or without BaO were fabricated by containerless processing. Scanning electron microscope observations and the scan profiles of electron-probe microanalysis demonstrated that the Ba-silicate glass was homogeneous and no aggregation of Er3+ ions occurred. The infrared fluorescence at around 1.55 μm from Er3+ in the Ba-silicate glass excited by a 980-nm laser was broader and its lifetime was longer than that of the silica glass, indicating the difference in the local structures around Er3+ ions between the Ba-silicate and silica glasses; this was supported by Raman scattering measurements. These results demonstrated that the Ba-silicate-glass system might be a new candidate for a host glass for Er3+-doped fiber amplifiers. 相似文献
125.
Xiang PH Asanuma S Yamada H Inoue IH Sato H Akoh H Sawa A Ueno K Yuan H Shimotani H Kawasaki M Iwasa Y 《Advanced materials (Deerfield Beach, Fla.)》2011,23(48):5822-5827
A prototype Mott transistor, the electric double layer transistor with a strained CaMnO(3) thin film, is fabricated. As predicted by the strain phase diagram of electron-doped manganite films, the device with the compressively strained CaMnO(3) exhibits an immense conductivity modulation upon applying a tiny gate voltage of 2 V. 相似文献
126.
Takashi Minemoto Hideyuki Takakura Yoshihiro Hamakawa 《Solar Energy Materials & Solar Cells》2006,90(20):3576-3582
A CdS film as an antireflective (AR) coating has been successfully deposited on spherical silicon solar cells by chemical bath deposition, which is a novel deposition method of AR coatings for spherical silicon solar cells. The CBD method is a growth method in an aqueous solution and enables film formation for electronic devices with arbitrary shapes. The solar cell performance of the cell with the CdS film showed a 16% increase in short circuit current compared to that without an ARC. The result confirms that the CBD method is useful for the ARC fabrication of spherical silicon solar cells. 相似文献
127.
New-type solar cells, having a structure “transparent conductor/thin Si02 layer with ultrafine metal islands as conductive channels/n-Si” have been prepared by forming a very thin (< 1.0 nm) silicon oxide (Si02) layer as well as platinum (Pt) islands (5–50 nm in size) embedded in it on a single crystal n-type silicon (n-Si) wafer, followed by the deposition of an indium tin oxide (ITO) film (200 nm thick) by the electron-beam evaporation method. The open-circuit photovoltages (Voc) of the solar cells of the above structure were relatively low, 0.25–0.47 V, but they increased very much to 0.50–0.59 V if a thin (3–10 nm) layer of an organic compound such as copper phthalocyanine (CuPc) was pre-deposited on the Pt-island modified n-Si wafer before the ITO deposition. The reason for the beneficial effect of the pre-deposition of the thin CuPc layer was investigated in detail, and it has been found that certain crystal defects are formed in n-Si near the n-Si/Si02 interface during the ITO deposition in the absence of the CuPc layer. The formation of such defects is prevented in the presence of the CuPc layer, which leads to a decrease in surface carrier recombination and hence to the increase in Voc. 相似文献
128.
Many indoor and outdoor factors (e.g., the presence of occupants, hot-water supply equipment, the use of hygroscopic materials, and ventilation) contribute to indoor humidity. It is important to investigate and understand the contribution of each factor to indoor humidity and to establish an effective method for the design and control of indoor humidity. In this study, indoor humidity was treated as a linear summation of the contribution of various factors, all of which can cause an increase or decrease in indoor humidity. New indices for assessing the contribution of factors to the humidity distribution in a room are proposed as Contribution Ratios of Humidity (CRI(H)) 1, 2, and 3 which can be calculated based on Computational Fluid Dynamics (CFD) simulations. Furthermore, a transient simulation based on CRI(H)1 and the Contribution Ratio of Indoor Climate (CRI(C)) was developed to predict the indoor humidity distribution. A 100-day transient analysis was performed in a living room in which moisture-buffering materials were used. The simulation results were compared with those from a well-mixed zonal model and a CFD transient analysis to confirm the effectiveness of the approach. The analysis provided the three-dimensional spatial distribution of indoor humidity and temperature with good prediction accuracy. The calculation time was approximately equal to that of the well-mixed zonal model and much faster than that of the CFD transient analysis. 相似文献
129.
Rie Matsushima-Nishiwaki Yoshihiro Shidoji Shinji Nishiwaki Tetsuya Yamada Hisataka Moriwaki Yasutoshi Muto 《Lipids》1995,30(11):1029-1034
Microcystin-LR is a liver tumor promoter in the okadaic acid class, a group of potent inhibitors of protein phosphatases 1
and 2A. Because of inhibition of protein phosphatases, microcystin-LR induces hyperphosphorylation of cellular proteins, including
cytoskeletal proteins—cytokeratins 8 and 18—and causes morphological changes in mouse hepatocytes in primary culture. We studied
the effects of carotenoids to antagonize microcystin-LR-induced morphological changes in hepatocytes. β-Carotene (100 nM to
100 μM), suppressed the morphological changes induced by 100 nM microcystin-LR in a dose-dependent manner. Other carotenoids
tested exerted similar suppressive effects, although retinoids, such as all-trans retinol, all-trans retinoic acid, and 9-cis retinoic acid, were only weakly suppressive. The relative potency of the suppression correlated significantly with the number
of conjugated double bonds in thetrans configuration. β-Carotene strongly suppressed the hyperphosphorylation of cellular proteins induced by microcystin-LR without
significant changes in the basal phosphorylation level. Other antioxidants, such as α-tocopherol, did not protect the cells
against microcystin-LR. Taken together, the antagonistic effects of carotenoids against microcystin-LR are difficult to explain
by their antioxidant or provitamin A activities. Suppression of the hyperphosphorylation of cellular proteins may be a novel
mechanism by which carotenoids inhibit tumor promotion. 相似文献
130.
This paper describes realtime network management support systems which have been developed forntt’s telephone network. In particular, the advanced traffic observation and management information collecting system referred to as Atomics and the traffic congestion control system referred to astcs are presented. The purpose of the development, concept, functions and capabilities of each system are explained. Examples of powerful realtime network management supported by Atomics andTSC are also presented. 相似文献