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101.
H. Kudo K. Okuno H. Sugai Y. Nagame 《Journal of Radioanalytical and Nuclear Chemistry》1985,93(1):55-64
Chemical states of tritium existing in neutron-irradiated solid lithium compounds were analyzed using a radiometric method. Nearly 100% of tritium was found in the T+ state in LiOH, Li2O2 and Li3N, while the T– state predominated in LiH, Li7Pb2 and Li2C2. Tritium incorporated in Li2O, Li2S, LiF, LiCl, LiBr and LiI was distributed over the T+, T– and T0 states. In Li2O crystals, the distribution of tritium in the T+ state increased from 58% to 81% with increasing neutron fluence from 2.5×1016 cm–2 to 6.3×1017 cm–2. 相似文献
102.
Photocatalyst Materials for Water Splitting 总被引:4,自引:0,他引:4
Akihiko Kudo 《Catalysis Surveys from Asia》2003,7(1):31-38
Various photocatalyst materials developed by the group of the present author are described. Alkali and alkaline earth tantalates have arisen as a new group of photocatalyst materials for splitting of water into H2 and O2 under ultraviolet irradiation. They showed activities even without co-catalysts such as Pt, being different from titanate photocatalysts. When NiO co-catalysts were loaded on the tantalate photocatalysts, the photocatalytic activities were markedly increased. Among the tantalates, NiO/NaTaO3 doped with La showed the highest activity. BiVO4, AgNO3, and TiO2 co-doped with Cr and Sb photocatalysts showed high activities for O2 evolution in the presence of a sacrificial reagent (Ag+) under visible light irradiation ( > 420 nm). Pt/SrTiO3 co-doped with Cr and Sb or Ta, Pt/NaInS2, and Pt/AgInZn7S9 photocatalysts showed high activities for H2 evolution from aqueous solutions containing reducing reagents under visible light irradiation. Furthermore, Cu- or Ni-doped ZnS photocatalysts showed H2 evolution activities even without co-catalysts such as Pt. 相似文献
103.
Three analytical methods for uranium by neutron activation are described. The methods are based on the substoichiometric separation of barium or lanthanum, which are the fission products of uranium-235 by neutron irradiation. Uranium contents in high purity materials were determined by the methods, which were found to be useful for the determination of a trace amounts of uranium. 相似文献
104.
Mikami K Angelaud R Ding K Ishii A Tanaka A Sawada N Kudo K Senda M 《Chemistry (Weinheim an der Bergstrasse, Germany)》2001,7(3):730-737
Asymmetric catalysts, prepared by chiral ligand exchange or chiral modification, can evolve further into highly activated catalysts through engineering with chiral activators. Two new methodologies for "super high-throughput screening" (SHTS) of chiral ligands and activators have been developed as a combination of HPLC-CD/UV (CD/ UV = circular dichroism/ultraviolet spectroscopy) or -OR/RIU (OR/RIU = optical rotation/refractive index unit) with a combinatorial chemistry (CC) factory. With these techniques, the % ee of the product is determined within minutes without separation of the enantiomeric products by using a nonchiral stationary phase. Therefore, those SHTS techniques combined with our 'asymmetric activation' concept can provide a powerful strategy for finding the best activated chiral catalyst. 相似文献
105.
The genetic polymorphisms of orosomucoid, ORM1 and ORM2, were analyzed by isoelectric focusing on polyacrylamide gels and subsequent immunoprinting. Sera from 600 unrelated individuals in Taiwan and Japan were examined. Five new alleles, designated ORM1*7, ORM1*8, ORM1*4.2, ORM2*8 and ORM2*10, were observed together with common and rare alleles that have been found in the Japanese and the Filipinos. As compared with the Japanese, the Taiwanese have a higher frequency of ORM1*1, and a significantly lower frequency of ORM1*2.1. 相似文献
106.
107.
Substoichiometric methods of analysis are simple in principle and involve the addition of a smaller amount of reagent than is required for complete reaction with the element to be determined. They can be used with great effect in trace analysis. 相似文献
108.
Y. Saiki M. Fukuzaki T. Sekine Y. Kino H. Kudo 《Journal of Radioanalytical and Nuclear Chemistry》2003,255(1):101-104
Particle growing processes were investigated for technetium(VII) sulfide (Tc2S7) colloids produced in a mixture of Na2S and TcO4
- solutions by laser-induced photoacoustic spectroscopy (LPAS). Analysis of the LPAS signal intensities indicated that the particle size increased in the solution with an increase of standing time, while the number of particles remained constant. It was revealed that the size of colloid particles increased by deposition of Tc2S7 on the particle surfaces, not by coagulation of colloid particles. The formation mechanism and growing process of the colloids are discussed based on the LaMer model, which deals with nucleation processes. 相似文献
109.
Murata Y Kudo S Kofuji K Miyamoto E Kawashima S 《Chemical & pharmaceutical bulletin》2004,52(10):1183-1185
The orotic acid (OT) salt of chitosan (CS), CS-OT, and that of a CS derivative, CP, were prepared, and the adsorption of primary or secondary bile acid was investigated. Calcium-induced alginate gel beads (Alg-Ca) containing CS-OT were also prepared and autoclaved, and the possibility of these beads to act as a vehicle for oral administration to prevent hyperlipidemia was investigated. When taurocholate (TCA) and glycocholate (GCA) were present together in the medium, CS-OT adsorbed identical amounts of both bile acids. This trend was seen in all CPs, although the capacity to adsorb bile acid was affected by the number and/or structure of the amino groups in the CP. On the other hand, taurodeoxycholate, a secondary bile acid was preferentially adsorbed over TCA and GCA. Alg-Ca containing CS-OT took up bile acids in a similar manner as CS-OT irrespective of the water content of the gel matrix. As all elements can be taken as a food, Alg-Ca containing CS-OT could serve as a useful dietary agent for the prevention of hyperlipidemia, which is a lifestyle-related disease. 相似文献
110.