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Abstract  

The glass transition of lyophilized materials is normally measured by conventional or temperature modulated differential scanning calorimetry (TMDSC). However, because of the weakness of these transitions when protein concentrations are high, these techniques are often unable to detect the glass transition (T g). High ramp rate DSC, where heating rates of 100 K per min and higher are used, has been shown to be able to detect weak transitions in a wide range of materials and has been applied to these materials in previous work. Dynamic mechanical analysis (DMA) is also known to be much more sensitive to the presence of relaxations in materials than other commonly used thermal techniques. The development of a method to handle powders in the DMA makes it now possible to apply this technique to protein and protein-excipient mixtures. HRR DSC, TMA and DMA were used to characterize the glass transition of lyophilized materials and the results correlated. DMA is shown to be a viable alternative to HRR DSC and TMA for lyophilized materials.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: Y. Kawabata, V. Aparin, M. Nagai, M. Yamamoto, K. Shiraishi, and Y. Katayama

Abstract  

Uranium and thorium concentrations in water and in soil from Kazakhstan have been investigated. In some sampling points the uranium concentrations of drinking water, exceeded the WHO guideline level for drinking water. Thus, the human effect of uranium exposure from drinking water in these areas is significant. However, soil samples were the same as in the Nature. Irrigation systems in these areas would be easy for water carried in the drains mix with groundwater. The results here suggest that the uranium passes into the groundwater through the agriculture land by the above mechanism.

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Abstract  

Content of 40 elements in plant leaves, soils and rocks collected from several sampling sites in Okayama Prefecture was analyzed by instrumental neutron activation analysis using the Research Reactor of Kyoto University. Of these, 16 elements were taken up, and the relationship among their amounts in plants, rocks and soils was discussed, focusing mainly on the essential elements of higher plants and related elements in the periodic table. Although most element contents in plant were different among species, the mediam values of the most non-essential elements in the leaf were lower than the contents in the soil and rock samples. However, essential elements showed significantly higher median values than those in the soil and rock samples. Most element contents in leaves showed a logarithmic normal distribution. The normal distribution was observed in most essential elements except for zinc, while non-essential elements did not show a normal distribution. The results obtained by analysis of variance, showed that the plant species studied could be divided into four major groups, namelyDicotyledoneae, Monocotyledoneae, Gymnospermae andPteridophyta. In general,Dycotyledoneae andPteridophyta had higher element contents thanMonocotyledonaeae andGymnospermae.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: Y. Kawabata, M. Yamamoto, V. Aparin, S. Ko, K. Shiraishi, M. Nagai, and Y. Katayama

Summary  

Water and phosphorous fertilizer samples from Karakalpakstan in the Republic of Uzbekistan were analyzed by inductively coupled plasma mass spectrometry, (ICP-MS) to demonstrate the water quality in drinking water, rivers and canals. Uranium concentrations exceeded the WHO (2004) guideline levels for drinking water at some sampling points. Since uranium can also have a toxic effect on kidneys, the effect of uranium from drinking water on people in these areas is significant. One of the main pollutant sources is the phosphate fertilizer leached from agriculture land.

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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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