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Abstract  

In order to develop new reference materials for microanalytical nuclear techniques, the Scanning Proton Microprobe (SPM) technique was used to determine homogeneity levels within 100×200 m2 micro-area on small pieces of IAEA Urban Dust reference materials. The experimental methods are described in detail. The results show that IAEA-396A/M Vienna Urban Dust is homogeneous enough for a SRM (10% for Si, S, K, Ca, Fe, Cu, Zn) for small sample analysis.

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Abstract  

Bone mineral density (BMD) determination has been performed in 210 selected Shanghai residents of both sexes of age range 15–50 using Hologic QDR-2000 dual energy X-ray absorptiometry (DEXA). The results showed that in female groups the peak value of L1-L4 BMD was 1.023 g/cm2 at the age of 31–35, but in the male groups it was 0.971 g/cm2 aged 26–30 and the peak period lasted till the group aged 46–50. The similar conclusion has also obtained by further statistics.

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Abstract  

The IAEA-386 bovine liver candidate reference material is prepared specially for micro-analytical techniques. The development process including material collection, drying, pulverizing, sieving, homogenization and preliminary test is described in detail. More effective grinding methods were established to achieve the median partiele size of 22 μm. For reasons of quality control and better assessment of resulting data, its certification campaigns on world-wide will be organized by the IAEA.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: Zhang Yuanxun, Zhang Yongping, Li Delu, Zhang Guilin, Long Jiangang, Shen Hui, Huang Yuying, and He Wei

Summary  

In order to explore the interaction between the expression of ZnT3 (Zinc Transporter 3) mRNA (Messenger Ribonucleic Acid) and the concentration of elemental zinc in mouse brain, zinc distribution in brain was determined by synchrotron radiation X-ray fluorescence (SRXRF) technique and a ZnT3 mRNA expression in tissue was examined by the reverse-transcriptase polymerase chain reaction (RT-PCR) method.The results show that the zinc concentration is not evenly distributed in brain slices. Its concentrations in cerebral cortex and hippocampus are nearly 5-10 times higher than those in other positions. A corresponding relation is that ZnT3 mRNA in cerebral cortex, hippocampus and testis has higher abundant degree, but it is not examined out in other tissues. Furthermore, the results promote that ZnT3 facilitates the accumulation of zinc in synaptic vesicles and may play an important role in structuring of vesicular zinc pool.

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Abstract  

This paper deals with the osteoporosis model of New Zealand rabbits in order to study the function of inorganic elements for women patients with osteoporosis. The thirty cases of iliac crest are collected and determined using neutron activation analysis (NAA). The results show that the fluorine concentrations in the experimental group are higher than those in control group and the magnesium concentrations are significantly lower (P<0.001), but the concentrations of K, Na, Ca, Ba, Mn, Sr show no remarkable difference. Combined with the serum biochemical markers of bone formation and resorption, the physiological functions of some metal elements in bone are also discussed.

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Abstract  

This study is a one-year monitoring of the inhalable particulate matter (PM10) of Shanghai (from January 2006 to December 2006) to study PM10 pollution. Proton-induced X-ray emission (PIXE) was used to investigate the chemical elements in Shanghai PM10. The study finds seasonal variation in both mass concentration and of chemical elements in PM10. The results of the enrichment factor show that the chemical elements in the inhalable particles could be divided into two categories, soil elements from earth crust and anthropogenic pollution elements. The high enrichment factors suggest that anthropogenic activities were the dominant source for elements such as S, Cu, Cl, Zn, Pb and Br. Strong correlation of K, Ca, Fe and Ti, from factor analysis, indicates these elements coming from earth crust or soil, S, Zn and Pb from industrial pollution and/or traffic and Cl from coal combustion.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: Yuanxun Zhang, Youngping Zhang, Yongpeng Tong, Shijing Qui, Xiaotao Wu, and Kerong Dai

Abstract  

Proton Induced X-ray Emission (PIXE) method is used for the determination of elemental concentrations in cancellous bone of human femoral head from five autopsies and seven patients with femoral neck broken. The specimen preparation and experimental procedure are described in detail. Using the t test, the results show that the concentrations of P, Ca, Fe, Cu, Sr in control group are higher than those in patient group, but the concentrations of S, K, Zn, Mn are not significantly different. The physiological functions of metallic elements in human bone are also discussed.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: Yinsong Wang, Aiguo Li, Yuanxun Zhan, Lun Wei, Yan Li, Guilin Zhang, Yaning Xie, Jing Zhang, Yuanmao Zhang, and Zuci Shan

Abstract  

The atmospheric particulate matter samples were collected in Shanghai, China. The X-ray absorption near-edge structure (XANES) spectra of Cr, Mn, Cu and Zn were measured. The XANES spectroscopy was used as a fingerprint to compare with that of reference materials to obtain speciation information. The oxidation state of these elements and main chemical components in the samples were described using the method. The results show that in our samples the oxidation state of Cr is trivalent, Mn mainly exists in the divalent state, Cu also exists in the divalent state, and Zn mainly exists in the zinc sulfate. For the XANES spectra of samples with different particle size and from different sampling site, we did not find their obvious differences. When we compared the XANES spectra of our samples with those of standard reference material SRM 1648, we found that they are similar in regards to the determined elements. The elemental concentrations in the samples were determined by proton induced X-ray emission (PIXE). The difference of elemental concentrations was observed in the different samples.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: Zhang Yuanxun, Lin Erhkang, Li Deyi, Wang Yinsong, Yu Yuehchung, Wang Changwan, Shen Waiguo, Zhi Min, Zhang Guilin, and Li Yan

Abstract  

In order to evaluate the evolution of contamination we collected river water and sediment samples in the every spring season since 1998. The elemental analysis of water and sediment samples was performed by PIXE using the 3×2 MeV NEC Tandem accelerator at the Taipei Institute of Physics. The characterization of - and -radioactive levels for water and sediment samples was performed by a BH1216, low background radioactivity instrument at the Shanghai Institute of Nuclear Research. The PIXE results showed that the elemental contents of Cl, K, Ca, Cr, Mn, Fe, Zn and Pb in river water gradually decreased with the rising tide. At high tide, their concentrations were minimum and then increased toward the ebb tide. The analysis also demonstrated that the radioactivity of water samples had been gradually decreasing year by year. It was found that the decreasing rate of -radioactivity was a little quicker than that of -radioactivity. Further aspects of environmental data evaluation and assessment are also discussed.

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