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991.
Hirokazu Asahara Daiju Takamizu Masaki Hirayama Shin Saito Tadahiro Ohmi 《Thin solid films》2010,518(11):2953-6157
MgZnO (magnesium-zinc-oxide) films were grown on (11-20) sapphire substrates and Zn-polar ZnO substrates by plasma enhanced metal-organic chemical vapor deposition (PE-MOCVD) employing microwave-excited plasma. Structural, electrical and optical properties were investigated by X-ray diffraction, atomic force microscope, Hall, transmittance and photoluminescence measurement. The c-axis lattice constant decreases proportionally to an increase in the Mg content of MgxZn1 − xO films. Therefore, this indicates that Mg atoms can be substituted in the Zn sites. Mg contents in films on ZnO substrates increase up to 0.11. In addition, Ga doped ZnO films were grown on (11-20) sapphire substrates. The resistivity of the films on (11-20) sapphire is controlled between 1.2 × 10− 3 Ω cm to 1 Ω cm by changing the process conditions. The overall results indicate the promising potential of this PE-MOCVD method for related (Zn, Mg)O films formation because of the reactivity of the radicals, such as oxygen radicals (O?). 相似文献
992.
993.
Ando M Seoka M Nakatani M Tsujisawa T Katayama Y Nakao M Tsukamasa Y Kawasaki K 《Journal of food protection》2008,71(3):595-601
Substantial amounts of mercury are usually present in tuna muscle, with levels in excess of 10 times the standard safety value present in some individuals. Inspection of individual fish for mercury content would be desirable but may not be cost-effective. In this study, we tried to establish a low-cost system for checking the mercury content of tuna by using a tail muscle that is usually discarded. The samples used in this experiment were bluefin tuna, cultured in the Fisheries Laboratory of Kinki University (Oshima Experimental Station, Wakayama, Japan). They were raised from eggs spawned in 2002. Ninety-eight individuals, weighing 22.3 to 61.6 kg, were selected between December 2004 and November 2005. In nine individuals, the mercury content of the tail was compared with that of the whole body. The total mercury level was measured using the reduction vaporizing atomic absorption method after acid digestion. Except for the front of the abdomen, where the mercury content was lower (0.490 ppm), the mercury content of other parts of the fish did not differ from that of the tail muscle (0.631 ppm). Therefore, the overall mercury concentration in bluefin tuna could be estimated to be almost the same and/or lower than that of the tail muscle. On the basis of these results, for 1 year we investigated the quantity of mercury in full-cycle cultured bluefin tuna that were shipped. The mercury concentration showed no increase irrespective of increases of body weight. 相似文献
994.
Masaki FUJIOKA Kiyoshi OKA Riko KITAMURA Aya YAKABE 《Hemodialysis international. International Symposium on Home Hemodialysis》2009,13(2):168-171
The number of patients requiring dialysis because of diabetes mellitus is increasing and such patients often have complex chronic wounds, which are difficult to heal. However, there are few retrospective studies of wounds requiring surgical treatment. We evaluated 14 patients receiving hemodialysis (HD) (8 because of diabetes and 6 because of other diseases) who had extremity wounds and underwent surgical treatment in our unit from 2004 through 2007. We investigated differences in the cause of wounds, and in the interval between the start of HD and wound development. Wounds in patients undergoing HD because of diabetes originated due to ischemia in 2 cases (25%), trauma in 2 cases (25%), and infection in 4 cases (50%). Seven of 8 wounds developed infection with methicillin-resistant Staphylococcus aureus (MRSA). Wounds in patients undergoing HD because of other diseases developed due to ischemia in 2 cases (33%) and trauma in 4 cases (67%). Three of 6 wounds developed infection and MRSA were isolated from 2 wounds. The interval between the start of HD and wound development was significantly shorter in patients with diabetes than in patients without diabetes. All patients with infectious wounds required immediate debridement. We conclude that patients receiving HD because of diabetes are likely to have more severe and rapidly developing wounds due to infections. Thus, they usually require immediate debridement before blood access shunt infection occurs. 相似文献
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997.
The gas barrier properties of isotactic polypropylene (iPP) and high‐density polyethylene (HDPE) are both significantly improved by diamond‐like carbon (DLC) deposition and photografting polymerization using acrylic acid (AA) monomers. In fact, the gas barrier properties can be highly improved just by DLC or by AA‐photografting polymerization. The improvement observed by AA‐photografting polymerization is more pronounced than that by DLC deposition in our general experimental condition. In more detail, the oxygen barrier property of DLC‐deposited and AA‐grafted iPP is considerably improved by ~10 times when compared with that of neat iPP. As for HDPE, the oxygen barrier property is enhanced by nearly six times through DLC deposition and photografting polymerization. By observing the surfaces, 30 nm layer of DLC and 1.0 μm of AA‐grafted layer are firmly constructed on the polyolefins, which should contribute to the enhancement of the oxygen barrier property. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 相似文献
998.
Toru Fujii Rei Yamakawa Yoshie Terashima Shinya Imura Keiichi Ishigaki Masakatsu Kinjo Tetsu Ando 《Journal of chemical ecology》2013,39(1):28-36
Females of a lichen moth, Barsine expressa (Arctiidae, Lithosiinae), which inhabit Iriomote Island in Japan, were captured by a black-light trap, and the pheromone gland extract was analyzed by gas chromatography (GC) with an electroantennographic (EAG) detector, and by GC coupled with mass spectrometry. The females produced several EAG-active esters, and the mass spectrum of a major component indicated the mixture consists of propionates derived from C17-saturated secondary alcohols, which were inseparable on the capillary GC column. In addition to these main components, the pheromone glands included two acetate derivatives of C17 alcohols, and other propionates of C16 and C15 alcohols. The crude extract was treated with K2CO3, and a 1:1 mixture of C17 alcohols with a C6- or C7-chain moiety was obtained. The two alcohols were uniformly converted into monodeuterated n-heptadecane by mesylation and succeeding LiAlD4 reduction. This result revealed a straight-chain structure of the C17 alcohols with the acyl groups located at the 7- or 8-position. Field tests on Iriomote Island showed that the synthetic esters were behaviorally active. A 1:1 mixture of racemic 7-propioxyheptadecane and 8-propioxyheptadecane, which were prepared from the secondary alcohols synthesized by a Grignard coupling reaction, attracted male moths. Furthermore, propionates of the alcohols synthesized enantioselectively by using a hydrolytic kinetic resolution with Jacobsen’s catalyst were evaluated. Only the traps baited with a mixture of the two esters with the same S-configuration significantly attracted B. expressa males. In the Tokyo area, the propionate mixture attracted a closely related species, Barsine aberrans aberrans. 相似文献
999.
1000.
The beta-cyclodextrin-modified Ag-TiO2 core-shell nanoparticles were prepared by sodium borohydrate reduction of AgNO3 and the subsequent hydrolysis of the tetraisopropyl orthotitanate in an aqueous medium. Inversely in the preparation of beta-cyclodextrin-modified TiO2-Ag core-shell nanoparticles, first hydrolysis and then following reduction were carried out. The synthesized spherical core-shell nanoparticles were highly water-dispersible and had an average diameter in the range of 9 to 12 nm. A significant shifting of surface plasmon band was observed for the synthesized Ag-TiO2 and TiO2-Ag core-shell nanoparticles. On a model reaction, namely, the photodegradation of phenol by the UV light irradiation, the photocatalytic property of TiO2 nanoparticles was enhanced, when the Ag nanoparticle was embedded in the core of TiO2 nanoparticles but TiO2 nanoparticles coated by Ag shell decreased the photocatalytic property of TiO2 nanoparticles. The mechanism is ascribed to the surface plasmon characteristics of Ag in the core of the TiO2 nanoparticles under the acceleration by host-guest inclusion characteristics. 相似文献