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Abstract  

Reaction mechanism of base hydrolysis of halobis/8-quinolinolato/oxotechnetium (V) /TcOX (ox)2 X=Cl and Br/ was investigated by means of solvent extraction and spectrophotometric methods. Furthermore, distribution coefficients of tris/acetylacetonato/technetium/III/, dichlorobis/8-quinolinolato/technetium/IV/ and TcOX/ox/2 between chloroform and aqueous solutions were determined. In an alkaline solution, TcOX/ox/2 decomposed to pertechnetate as a final product. On the basis of the established base hydrolysis, the respective rate constants were determined.

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Abstract  

Chlorobis/-diketonato/ oxotechnetium/V/ complexes [TcOCl/-dik/2, -diketone=acetylacetone, benzoylacetone and dibenzoylmethane] were newly synthesized using macroamount of99Tc. These complexes were further separated into geometrical isomers. Furthermore, an improvement of the yields for the syntheses of tris/-dike-tonato/technetium/III/ complexes [Tc/-dik/3, -diketone=acetylacetone, benzoylacetone and 2-thenoyltrifluoroacetone] was examined using Tc/III/-thiourea complexes as a starting material.

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Summary The mixing state of amphiphilic di-block copolymers consisted of poly(ethylene oxide) and poly(methacrylate) having azobenzene moieties in the side chains p(EO)114pMA(Az)24 and poly(ethylene oxide) p(EO)114 was investigated from the viewpoints of isothermal crystallization and nano-scale ordered structure. The chemical potential, which required establishing the constant crystal growth rate, decreased with the p(EO) content up to 60%. The hexagonal packed cylinder structure was observed for the blends with the p(EO) content up to 60% and the lattice spacing of (100) and (110) planes increased with the p(EO) content up to 60%. The blends of amphiphilic p(EO)114pMA(Az)24 and p(EO)114 were miscible without in the p(EO) content below 60%.

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Abstract  

Tritium concentration of organically bound hydrogen has been measured during the 1941 to 1987 period using a cellulose fraction extracted from pine tree grown in Tatsunokuchi-machi, Ishikawa Prefecture, Japan. It was concluded that most of the tritium bound in cellulose was supplied from the mixture of underground water in the root zone of the pine tree. Underground water was strongly influenced by the precipitation and waters with different residence times.

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Abstract  

Mössbauer parameters of tin compounds, Sn(CH3)nCl4–n (n=0, 1, 2, 3, 4), isolated in low temperature matrices are correlated with electronic properties at the tin nuclei obtained by molecular orbital calculations. The Mössbauer isomer shift and quadrupole splitting show good correlation with electron density and electric field gradient estimated by molecular orbital calculations, respectively. Structures of novel species (Sn(CH3)2CH2 and [Sn(CH3)2CH2]2) produced via photodissociation of Sn(CH3)4 in low temperature matrices were estimated by means of molecular orbital calculations as compared with Mössbauer parameters.

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Abstract  

All of the combustion water samples extracted from cellulose in pine tree rings corresponding to the 1983–1987 period showed elevated tritium concentrations of approximately 65 pCi/dm3, which were 30 to 35 pCi/dm3 higher than those for precipitation and atmospheric vapor in recent years. In addition, other environmental samples, viz. the tissue-free water in tree rings, and of combustion and tissue-free water in pine needles and spring water near the pine tree site also showed concentrations similar to the combustion water of cellulose. These findings suggest that most of the tritium in tree rings was supplied from underground water containing a high tritium concentration in the root zone of the pine tree.

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Abstract  

At Tsugu mine in Aichi Prefecture, antimony was mined and smelted until 1956. The amounts of antimony present in the soil of the abandoned mine were measured to enable us to detect any traces of the operation of the mine and to measure the level of environmental contamination with antimony. The quantity of antimony in rings of hinoki and sugi was also measured to obtain information about chronological changes in environmental conditions. The quantity of antimony in the samples was determined by INAA. The antimony concentrations in eight soil samples at different points in the Tsugu mine area were 8–17,000 ppm.

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Journal of Radioanalytical and Nuclear Chemistry
Authors:
Y. Kobayashi
,
Y. Tsuruoka
,
M. Kubo
,
H. Nonaka
,
Y. Yamada
,
Y. Sakai
,
H. Shoji
,
W. Sato
,
A. Shinohara
,
Y. Watanabe
, and
H. Matsue

Abstract  

In order to investigate the physical and chemical effects of neutron capture reaction, a neutron in-beam Mössbauer spectroscopic study on two isomorphs of iron disulfide: pyrite and marcasite, were carried out with a parallel plate avalanche counter at room temperature. In both compounds only two major products accounted for the obtained spectrum: one with Mössbauer parameters close to the parent compound and the other one considered to be a new product. The yield of the parent-like species was different in the two isomorphs.

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Journal of Thermal Analysis and Calorimetry
Authors:
K. Moriya
,
T. Yamada
,
K. Sakai
,
S. Yano
,
S. Baluja
,
T. Matsuo
,
I. Pritz
, and
Y. Vysochanskii
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Abstract  

Iron oxides, magnetite Fe3O4 and hematite Fe2O3 were laser-deposited onto Al substrates at various temperatures, and the Mössbauer spectra of the films were measured. The compositions of the films changed depending on the formation temperature of the substrate, oxide deficiency in the lattice structures and the formation process of the iron oxides. The films were composed of Fe3−x O4 and Fe1−x O independent of the laser-evaporation source (magnetite or hematite). Fe3−x O4 was seen to be dominant at higher temperatures and Fe1−x O was dominant at lower temperatures. The compositions of the films were confirmed by X-ray diffraction (XRD) measurements, and the surfaces of the deposited films were examined using scanning electron microscopy (SEM).

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