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451.
K. Nagano T. Mochida K. Shimakura K. Murashita S. Takeda 《Solar Energy Materials & Solar Cells》2003,77(3):2287
The authors have developed experimental thermal-photovoltaic (PV) hybrid exterior wallboards that incorporate of PV cells. The clapboard-shaped hybrid wallboards permit modular assembly that can be more easily adapted for building applications than previous PV systems. Solar heat is collected in the form of heated air circulating in the air gap between the hybrid wallboard and the thermal insulation of the exterior walls. This paper presents an evaluation of both the electrical power generating ability and the solar heat collection capacity during winter of six variations of the experimental thermal-PV hybrid wallboard. In addition, exergy analyses were conducted. 相似文献
452.
Huh JH Hermannstädter C Sato H Ito S Idutsu Y Sasakura H Tanaka K Akazaki T Suemune I 《Nanotechnology》2011,22(4):045302
We introduce a novel three-step procedure for precise niobium (Nb)-etching on the nanometer-scale, including the design of high contrast resist patterning and sacrifice layer formation under high radio frequency (RF) power. We present the results of precise slit fabrication using this technique and discuss its application for the production of superconducting devices, such as superconductor-semiconductor-superconductor (S-Sm-S) Josephson junctions. For the reactive ion etching (RIE) of Nb, we selected CF(4) as etchant gas and a positive tone resist to form the etching mask. We found that the combination of resist usage and RIE process allows for etching of thicker Nb layers when utilizing the opposite dependence of the etching rate (ER) on the CF(4) pressure in the case of Nb as compared to the resist. Precise slit-width control of 80 and 200 nm thick Nb apertures was performed with three kinds of ER control, for the resist, the Nb, and the underlying layer. S-Sm-S Josephson junctions were fabricated with lengths as small as 80 nm, which can be considered clean and short and thus exhibit critical currents as high as 50 μA. Moreover, possible further applications, such as for apertures of superconducting light emitting diodes (SC LEDs), are addressed. 相似文献
453.
Synthesis,chemical, and thermoelectric properties of n‐type π‐conjugated polymer composed of 1,2,4‐triazole and pyridine rings and its metal complexes 下载免费PDF全文
A soluble n‐type π‐conjugated polymer ( polymer 1 ) composed of a 1,2,4‐triazole ring substituted by a 4‐n‐octylphenyl subunit at the 4‐position of the 1,2,4‐triazole ring and pyridine‐2,5‐diyl rings was synthesized by Ni(cod)2 (cod = 1,5‐cyclooctadiene) promoted dehalogenation polycondensation of 3,5‐bis(2‐bromopyridyl)‐4‐n‐octylphenyl‐1,2,4‐triazole ( monomer 1 ). A polymer complex ( polymer‐BiCl3 ) was synthesized by the reaction of polymer 1 with BiCl3. The UV–vis spectrum of polymer 1 exhibited an absorption maximum (λmax value) at a longer wavelength than that exhibited by monomer 1 revealing that its π‐conjugation system was expanded along the polymer chain. Polymer 1 was electrochemically active in film, and the electrochemical reaction was accompanied with electrochromism. Thermoelectoric properties of polymer 1 and polymer‐BiCl3 were investigated. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 39928. 相似文献
454.
The aim of this study was to evaluate tissue distribution of vitamin E isoforms such as α- and γ-tocotrienol and γ-tocopherol
and interference with their tissue accumulation by α-tocopherol. Rats were fed a diet containing a tocotrienol mixture or
γ-tocopherol with or without α-tocopherol, or were administered by gavage an emulsion containing tocotrienol mixture or γ-tocopherol
with or without α-tocopherol. There were high levels of α-tocotrienol in the adipose tissue and adrenal gland, γ-tocotrienol
in the adipose tissue, and γ-tocopherol in the adrenal gland of rats fed tocotrienol mixture or γ-tocopherol for 7 weeks.
Dietary α-tocopherol decreased the α-tocotrienol and γ-tocopherol but not γ-tocotrienol concentrations in tissues. In the
oral administration study, both tocopherol and tocotrienol quickly accumulated in the adrenal gland; however, their accumulation
in adipose tissue was slow. In contrast to the dietary intake, α-tocopherol, which has the highest affinity for α-tocopherol
transfer protein (αTTP), inhibited uptake of γ-tocotrienol to tissues including adipose tissue after oral administration,
suggesting that the affinities of tocopherol and tocotrienol for αTTP in the liver were the critical determinants of their
uptake to peripheral tissues. Vitamin E deficiency for 4 weeks depleted tocopherol and tocotrienol stores in the liver but
not in adipose tissue. These results indicate that dietary vitamin E slowly accumulates in adipose tissue but the levels are
kept without degradation. The property of adipose tissue as vitamin E store causes adipose tissue-specific accumulation of
dietary tocotrienol. 相似文献
455.
Dihomo-γ-linolenic acid (DGLA) is one of the polyunsaturated fatty acids, and is expected to show anti-allergic activity. We examined the effects of supplementation with DGLA-enriched oil (450 mg as free DGLA) for 4 weeks in healthy adults in a randomized controlled study. The DGLA composition in the total fatty acids of serum phospholipids increased from 2.0 to 3.4%, and returned to the initial level after a 4-week washout. No side effects or changes in blood biochemical parameters were observed. These results indicate that serum DGLA content can be safely increased by supplementation with 450 mg DGLA under these conditions. 相似文献
456.
Kazuma Higashisaka Yasuo Yoshioka Kohei Yamashita Yuki Morishita Huiyan Pan Toshinobu Ogura Takashi Nagano Akiyoshi Kunieda Kazuya Nagano Yasuhiro Abe Haruhiko Kamada Shin-ichi Tsunoda Hiromi Nabeshi Tomoaki Yoshikawa Yasuo Tsutsumi 《Nanoscale research letters》2012,7(1):555
Practical uses of nanomaterials are rapidly spreading to a wide variety of fields. However, potential harmful effects of nanomaterials are raising concerns about their safety. Therefore, it is important that a risk assessment system is developed so that the safety of nanomaterials can be evaluated or predicted. Here, we attempted to identify novel biomarkers of nanomaterial-induced health effects by a comprehensive screen of plasma proteins using two-dimensional differential in gel electrophoresis (2D-DIGE) analysis. Initially, we used 2D-DIGE to analyze changes in the level of plasma proteins in mice after intravenous injection via tail veins of 0.8 mg/mouse silica nanoparticles with diameters of 70 nm (nSP70) or saline as controls. By quantitative image analysis, protein spots representing >2.0-fold alteration in expression were found and identified by mass spectrometry. Among these proteins, we focused on hemopexin as a potential biomarker. The levels of hemopexin in the plasma increased as the silica particle size decreased. In addition, the production of hemopexin depended on the characteristics of the nanomaterials. These results suggested that hemopexin could be an additional biomarker for analyzing the biological responses associated with exposure to silica nanoparticles. We believe that this study will contribute to the development of biomarkers to ensure the safety of silica nanoparticles. 相似文献
457.
Saki Hikosaka Yoshimichi Ohki 《IEEJ Transactions on Electrical and Electronic Engineering》2012,7(2):116-120
Dielectric properties of poly(phenylene sulfide) (PPS), a kind of super engineering plastic, were investigated over a wide temperature range by measuring its frequency spectra of complex permittivity and thermally stimulated polarization and depolarization currents (TSPC and TSDC). Experimental results indicate that its permittivity and dielectric loss factor remain stable and maintain low values up to around 140 °C, despite the fact that its glass transition appears at a much lower temperature of 88 °C. As for TSPC and TSDC, a very small peak associated with the glass transition appears at about 110 °C. Furthermore, a much clearer TSPC peak due to orientation of dipole moments associated with the ether linkage induced by the cross‐linking reaction appears at about 150–170 °C. The corresponding TSDC peak due to randomization of these dipoles is very small compared to the TSPC peak, since PPS was cross‐linked during the high‐temperature process in the TSPC measurement, which made rotation of the dipoles difficult. At temperatures higher than 150 °C, both the real and imaginary parts of the complex permittivity show significant increases with increase in temperature and decrease in frequency. This is attributable to the transport of the charge carriers. © 2011 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献