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Abstract  

Human hair collected from the mercury, arsenic and cadmium polluted areas has been analysed by instrumental neutron activation method. The concentrations of 27 elements were compared with those of normal Japanese. Correlation coefficients of logarithmic concentrations between the elements were calculated and their significance levels were determined. Factor contribution and factor loadings of the elements were calculated for each factor by making use of principal component analysis. The factor score of each sample was also calculated for each factor to examine the effects of the contamination by heavy metals on individuals.

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Abstract  

To investigate the present situation of inhabitants living in the cadmium polluted area of Toyama Prefecture of Japan, 95 hair samples were analyzed by neutron activation method. The median and the geometric standard deviation were determined from a cumulative frequency distribution curve of the elemental concentrations for each of 3 groups: male, female without perm and female with perm which were divided furthermore by two age ranges: 20 age<50 and 50 age. These concentrations were compared with those in some organs and urine reported.

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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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Abstract  

D-erythro sphingomyelines (SM) having a defined acyl chain were synthesized with sphingosylphosphorylcholine as a starting material, and both a structural property and its relating phase transition phenomenon were compared between a symmetric chain length SM (palmitoyl-SM: C16-SM) and asymmetric chain length SMs (behenoyl-SM: C22-SM, lignoceryl-SM: C24-SM). Furthermore, effect of increasing a content of asymmetric chain SMs in the mixture systems of C22-SM/C16-SM, and C24-SM/C16-SM was investigated. The present calorimetric and electron microscopic studies revealed that (1) The main transition enthalpy is smaller for the asymmetric chain SMs than for the symmetric chain SM by about 3 kJ mol−1, although the acyl chain length is longer for the former than for latter; (2) Relatively small size vesicles (100∼200 nm diameters) surrounded by one or more lamellae are observed for the asymmetric chain SMs, in contrast to large multilamellar vesicles (1500∼2500 nm diameters) having at least fifteen stained lamellae for the symmetric chain SM and (3) The coexisting asymmetric chain SMs cause the decrease in size and multiplicity for the MLV of the symmetric chain SM, simultaneously with a decrease in the main transition enthalpy.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: S. Ohmori, H. Tsuji, Y. Kusaka, T. Takeuchi, T. Hayashi, J. Takada, M. Koyama, H. Kozuka, M. Shinogi, A. Aoki, K. Katayama, and T. Tomiyama

Abstract  

With the aim of indicating environmental pollution effects by heavy metals on humans using hair, nondestructive activation analysis was applied to 382 normal Japanese hair samples (background level). Elemental contents of hair could be determined for Ag, Al, As, Br, Ca, Cd, Cl, Co, Cr, Cu, Fe, Hg, I, K, La, Mg, Mn, Na, S, Sb, Sc, Se, Sm, Ti, V and Zn. As these elements in hair have wide concentration ranges, the differences in concentrations distribution between groups (sex, age, permanent treatment and regional difference) are discussed. A method for hair sampling is presented.

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