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Abstract  

Seven representative wood species constituting caatinger forest were chosen to analyze Sc, V, Cr, Mn, Fe and Co, as well as Na, Mg and Al, by instrumental neutron activation analysis. In most cases of the soil, the concentration of the element tended to be higher with the increase of depth. Generally, the element partition from soil to root was higher in Mg and Co, whereas V showed higher partition rate from root to bark. The correlation within the elements was higher in the order of soil, root and bark.

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Journal of Thermal Analysis and Calorimetry
Authors: T. Shibasaki, T. Furuya, J. Kuwahara, Y. Takahashi, H. Takahashi, and T. Hashimoto

Summary Structural phase transitions upon the application of high pressure in LaGaO3 and LaCrO3, which were prospected from diffraction and thermal analyses of phase transition under ambient pressure, were discovered by using high-pressure X-ray diffraction. It was revealed that the crystal structures of LaCrO3 and LaGaO3 changed completely from that of orthorhombic distorted perovskite to that of a rhombohedral distorted one upon the application of pressure higher than 5.4 and 3.0 GPa, respectively, at room temperature. The variation of lattice constants with pressure was investigated for the high-pressure rhombohedral phases of LaCrO3 and LaGaO3 and isothermal compressibility was estimated. The variation of lattice constants with pressure at room temperature in the high-pressure rhombohedral phase was compared with that with temperature at ambient pressure in high-temperature rhombohedral phase. It was found that the application of pressure decreased the crystal symmetry, which was opposite to the result in the case of increasing the temperature.

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Abstract  

This work describes the synthesis, IR and UV-Vis spectroscopic characterization as well the thermal behavior of the [NiCl2(HIPz)4]⋅C3H6O (1), [Ni(H2O)2(HIPz)4](NO3)2 (2), [Ni(NCS)2(HIPz)4] (3) and [Ni(N3)2(HIPz)4] (4) (HIPz=4-iodopyrazole) pyrazolyl complexes. TG experiments reveal that the compounds 14 undergo thermal decomposition in three or four mass loss steps yielding NiO as final residue, which was identified by X-ray powder diffraction.

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Abstract  

The Mössbauer spectrum of LiFeVPOx, LiFeV0.5POx and LiFePOx glasses prepared by conventional melt-quenching method for cathode active material is composed of a doublet due to distorted FeIIIO4 tetrahedra. The Mössbauer spectrum of LiFePOx glass has an additional doublet due to distorted FeIIO6 octahedra. Heat treatment of LiFeVPOx and LiFeV0.5POx glasses at a given temperature close to each crystallization temperature causes a marked decrease in the value of Δ, reflecting a decrease in the distortion or an increase in the local symmetry of distorted FeIIIO4 tetrahedra. Heat treatment of LiFeVPOx glass causes an increase in the electric conductivity from the order of 10−7 to 10−3 S·cm−1, together with an increase in the specific discharge-and charge-capacity of a coin-type Li-ion cell from 50 to 150 mAh·g−1. These results prove that structural relaxation of the glass network causes an increase in the electric conductivity and an increase in the energy density of the Li-ion cell.

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Abstract  

155Gd Mössbauer spectra of some Gd(III)-b-diketonato complexes are reported. All of their 155Gd Mössbauer isomer shift (d) values fall in a narrow range of +0.55-+0.65 mm.s-1, and are between those of GdF3 and the cubic form of Gd2O3. This indicates that their Gd-O bonds have small covalent character. The value for quadrupole coupling constant (e2qQ) spread out from 1.67 to 7.56 mm.s-1 and reflects the difference well in symmetry of the coordination polyhedron around Gd(III) ions for those Gd(III)-b-diketonato complexes.

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Abstract  

Eighteen trace elements, including seven rare earth elements (REEs), and major and minor elements in the sediment samples from the Japan Sea and the northwestern Pacific near Japan were determined with instrumental neutron activation analysis (INAA). Most REE patterns (chondrite-nomalized) of the sediments were nearly identical to the patterns of terrigenous materials without cerium anomaly whereas the La/Yb ratio varied with the site locations. The variation of the La/Yb ratio of the sediments may indicate the regional variation of the mixing proportion of the terrigenous materials from the continent to the materials from the volcanic island arcs including the Japanese islands. The Th/Sc ratio of the sediments tended to increase with distance from the island-arc volcanism. Regional variation of the Th/Sc ratio may indicate variation of amount of the continental terrigenous materials supplied to the sediments.

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Abstract  

This work describes the synthesis, IR and 13C CPMAS NMR spectroscopic as well the thermal characterization of the new dicarboxylate complexes [Pd2(ox)2(4,4′-bipy)]n (1), [Pd2(ox)2(bpe)]n (2) and [Pd2(ox)2(pz)]n (3) {ox = oxalate, bipy = 4,4′-bipyridine, bpe = 1,2-bis(4-pyridyl)ethane, pz = pyrazine}. TG experiments reveal that compounds 13 undergo thermal decomposition in three steps. Metal palladium was the final product of the thermal decompositions, which was identified by X-ray powder diffraction.

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Abstract  

The synthesis and thermal behavior of the new [Pd(fum)(bipy)]n·2nH2O (1), [Pd(fum)(bpe)]n·nH2O (2) and [Pd(fum)(pz)]n·3nH2O (3) {bipy = 4,4′-bipyridine, bpe = 1,2-bis(4-pyridyl)ethene and pz = pyrazine} fumarate complexes are described in this work as well their characterization by IR and 13C CPMAS NMR spectroscopies. TG curves showed that the compounds released organic ligands and lattice water molecules in the temperature range of 46–491 °C. In all the cases, metallic palladium was identified as the final residue.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: J. Akashi, I. Fukushima, A. Imahori, S. Shiobara, Y. Takahashi, and K. Tomura

Abstract  

Scalp hair samples were collected from 75 zinc mine workers at the Nakadatsu Mine in Fukui Prefecture and were subjected to instrumental neutron activation analysis for determination of Cu, Cl, Mn, Ca, Au, Br, As, Na, K, Hg, Zn and Co concentrations. For determination of Cd, atomic absorption spectrophotometry was applied to approximately a half of the samples. The results were compared with the data of inhabitants of Suginami Ward in the Tokyo Metropolitan Area. Excessive concentration in the mean values of Zn, Cu, Mn and Hg was observed in the hair of the miners as compared with the Suginami residents. On the other hand, the mean concentrations of K and Cl in the hair of the miners were lower than those of the Suginami inhabitants.

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