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- Author or Editor: Y. Nakano x
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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.
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.
This study examined the aging effect on disuse muscle atrophy prevention using heat stress. Wistar rats aged 7 and 60 weeks were divided into three groups as follows: control, immobilized (Im), and immobilized and heat stressed (ImH). Heat stress was given by immersing the hindlimbs in hot water (42 °C) for 60 min, once in every 3 days and the gastrocnemius (GAS) and soleus (SOL) muscles were extracted after 14 days. Muscle-fiber types were classified using ATPase staining. Heat shock protein 70 (HSP70) was assessed through Western blotting. In GAS muscle of both groups and SOL muscle of 7-week-old rats, the fiber diameter of each muscle type in the ImH group significantly increased compared with that in the Im group. However, this could not be observed in the SOL muscle of the 60-week-old rats. The increased percentage of type-I fibers and variability of types I and II muscle-fiber diameter were evident in the SOL muscle of the 60-week rats. HSP70 was significantly elevated in the ImH group compared with in the Im group in both muscle types of both age groups. Thus, effectiveness of heat stress in the prevention of disuse muscle atrophy appears unsatisfactory in aging muscle fibers.
Abstract
An experimental method is described for the synthesis of195mPt-radiolabeled (–)-(R)-2-aminomethylpyrrolidine (1,1-cyclobutanedicarboxylato)-2-platinum (II) (DWA2114R). An amount of 10 mg of 95% enriched194Pt was irradiated for 75 h in the hydraulic conveyer of the KUR at a thermal neutron flux of approximately 8.1×1013 n.cm–2.sec–1 and the195mPt-radiolabeled DWA2114R was purified using HPLC. The chemical yield is higher than 65%, its chemical purity is greater than 99.2%, the radiochemical purity is nearly 100%, and the specific activity is 6.7 MBq. mg–1 DWA2114R.
Abstract
Instrumental neutron activation analysis was applied to the determination of trace impurity elements in a silicon single crystal. Impurity concentrations in polysilicon melt were compared with those in a single crystal. Impurity concentrations in artificial quartz were also compared with those in natural quartz. Segregation coefficients in Au, Ir and Sb were determined at different concentrations. The segregation coefficient of an element in a silicon single crystal is constant over a critical concentration, it becomes larger gradually under the critical one, and at last it becomes larger than 1.
Abstract
Neutron activation analysis was applied to the determination of trace impurity elements in a silicon ingot. Detection limits of 36 elements were calculated semi — empirically and compared with minimum concentrations detected in a silicon single crystal. The sources of the impurities were estimated from element concentrations detected in polycrystalline silicon and a quartz crucible. Segregation coefficients were determined from the concentration curves in a single crystal and discussed by comparing with reported values.
Calorimetric study on inclusion of some alcohols into α-cyclodextrin cavities
Molecular mechanical calculation of hydration Gibbs energies
Abstract
The enthalpies of transfer 2-propanol, 1,2-butanediol (BD) and 1-hexanol from aqueous to aqueous α-cyclodextrin (CD) solutions have been determined by microcalorimetry at various mole fractions at 298.15 K. To clarify stabilities of inclusion complexes in aqueous solutions, hydration Gibbs energies calculation of inclusion complex of CD-alcohol were performed by using the molecular mechanics with the MMFF94s force field in the generalized born/surface area (GB/SA) model. The largest stabilization in Gibbs energy is obtained by the hydration (Δhyd H) of α-CD-1,2-butanediol complex among α-CD-butanediol isomers complexes.
Abstract
The new control system of pneumatic transportation apparatuses for neutron irradiation in Kyoto University Reactor (KUR) has been developed based on the TCP/IP network for the purpose of integrated management of the apparatus. The control system is comprised of PLCs, control PCs, database and web servers. Archiving logs of detailed information about irradiation enables the secure operation and management of the irradiation system. The information stored in the server can be referred by remote PCs and mobile phones through the internet. Combining the present facility with measurement and radiation management systems it can realize advanced INAA methods and secure managements of radioisotopes.
