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Fukuwatari T Toriochi M Ohta M Sasaki R Shibata K 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2004,45(1):1-7
Bisphenol A, a monomer of polycarbonate plastics, disturbed the conversion pathway of the amino acid tryptophan to the vitamin nicotinamide. The conversion ratio of tryptophan to nicotinamide was reduced to 1/15 by feeding a diet containing 1% bisphenol A. A putative disturbing reaction is kynurenine-->3-hydroxykynurenine, which is catalyzed by kynurenine monohydroxylase. This is an FAD-enzyme and requires NADPH as a coenzyme. Styrene monomer (1% addition to a normal diet) did not affect the food intake or the body weight, but slightly reduced the conversion ratio of tryptophan-nicotinamide. 相似文献
54.
Vergleich von Hochofenbetriebsergebnissen mittels Leistungs-Faktor-Definition. Bestimmung der Lage und Form der Schmelzlinie im Hochofen durch Betriebsdaten. Wärmeeinbringen durch Blasform und deren Übertragung durch Konvektion und Strahlung. Einfluß der Wärmebedingungen im Unterofen auf die Lage der Schmelzlinie. Vergleich und Überprüfung der Modellprofile durch Betriebsmessungen. Einfluß verschiedener Unterofenparameter auf Hochofenbetrieb und Schmelzlinie. Schmelzgeschwindigkeit bei W- und ∧-Profilen in Abhängigkeit der Strahlungstemperatur. Untere kritische Höhenlage der Schmelzlinie und dynamisches Verhalten der Schmelzlinie. 相似文献
55.
Polymer film-type channel electron multipliers (CEMs) were developed and their characteristics investigated in comparison with bulk-type flexible CEM. As film-type CEMs, a paint-coating-type CEM and a solvent-etching-type CEM were fabricated. The paint-coating-type CEM is made by coating a “paint” which is prepared by dissolving in a solvent an electronically conductive polymeric composition having a high secondary electron emission yield. Up to the present study the mean gain of the film-type CEM, in spite of the lower resistivity of the dynode, seems to be slightly more dependent on the count rate than that of the bulk-type CEM made of the same material. However, the convenience of fabricating the dynode film by coating the dynode-forming paint on the internal surface of any shaped tube or a flexible polymer tube would overcome the slight disadvantage mentioned above. 相似文献
56.
Nomura SM Tsumoto K Hamada T Akiyoshi K Nakatani Y Yoshikawa K 《Chembiochem : a European journal of chemical biology》2003,4(11):1172-1175
Functional protein synthesis was observed in cell-sized lipid vesicles following encapsulation of a gene-expression system. Expression of rsGFP (red-shifted green fluorescent protein) within individual vesicles was observed by fluorescence microscopy. Interestingly, at the early stage of the reaction, the expression efficiency inside the vesicle was remarkably higher than that in the solution outside. The synthesized rsGFP in individual vesicles is safe from attack by proteinase K added to the external aqueous solution. Studies on cell-sized vesicles expressing protein should contribute to a fundamental understanding of certain aspects of living systems and will be useful for practical applications, such as the construction of microreactors. 相似文献
57.
Masaharu Nagayama Tsutomu Ikeda Tetsuya Ishiwata Norikazu Tamura Manshi Ohyanagi 《Journal of Materials Synthesis and Processing》2001,9(3):153-163
In the present paper, by using a mathematical model for self-propagating high-temperature synthesis, we reveal the three-dimensional structure of so-called spin combustion wave on the inside of cylindrical sample. It is shown that an isothermal surface of regular spin combustion wave has some wings of which number is the same as that of reaction spots on the cylindrical surface and that the isothermal surface with helical wings rotates down with time. Because of this propagating pattern, in this paper, we adopt the more suitable term helical wave. We also obtain the following existence conditions of a helical wave: If physical parameters are set so that a pulsating wave exists stably for the one-dimensional problem, then a helical wave takes the place of a pulsating wave when the radius of cylindrical sample becomes large. 相似文献
58.
A kinetic model based on the principle of maximum degradation rate of the total system free energy, MDR law using thermodynamic data, is proposed and successfully applied to the selection of the first intermetallic compound (IMC) phase in Cu/Sn and Ni/Sn diffusion couples. The first phases predicted with this model for Cu/Sn and Ni/Sn are Cu6Sn5 and Ni3Sn4, respectively, resulting in good agreement with experimental observations. 相似文献
59.
Kunihiro Suzuki Yuji Kataoka Susumu Nagayama Charles W. Magee Temel H. Buyuklimanli Tsutomu Nagayama 《Electron Devices, IEEE Transactions on》2007,54(2):262-271
We evaluated the redistribution profiles of ion-implanted impurities during solid-phase epitaxy using Rutherford backscattering spectrometry (RBS). RBS data revealed that the As concentration changes only near the moving amorphous/crystal interface. We derived an analytical model for the redistribution profiles using a segregation coefficient m between amorphous and crystalline Si, introduced a parameter of reaction length l that is the distance where impurities were exchanged, and obtained good agreement with experimental data with an m value of 3 and an l value of 1 nm for As. Furthermore, we applied our model to P and B redistribution profiles and obtained good agreement with corresponding m value of 4 and l value of 1 nm for P and m value of 0.3 and l value of 1 nm for B 相似文献
60.
Nylon-polystyrene microcapsules with immobilized ferroelectric liquid crystalline segments were prepared, and the permeability control of the encapsulated core material was investigated under an external electric field. A ferroelectric liquid crystal monomer possessing both mesogenicity and chirality effectively responded to an external electrical field. Permeation of the material (oxprenolol) contained in the inner aqueous core of the microcapsules was enhanced under a feeble electric field (2 V). Furthermore, it was found that the permeability of the microcapsules without the ferroelectric liquid crystal group did not depend on the external electrical field. In order to clarify the controlled release mechanism of the core material, the transmittance was quantitatively evaluated under an external electric field using a handmade polarized light transmittance apparatus. 相似文献