This study aimed to assess trace element concentrations in the hair of street children. Nutritional status was assessed by 24 hours’ dietary recall and anthropometric measurements. Data analysis found that Br, Sc, Sm...This study aimed to assess trace element concentrations in the hair of street children. Nutritional status was assessed by 24 hours’ dietary recall and anthropometric measurements. Data analysis found that Br, Sc, Sm and Ti concentrations show a normal distribution, and there is no significant difference between street children and control group. However, in the street children’s hair, the levels of Au, U, V are decreased and the levels of Co, La, Sb, Th are increased compared to the control group.展开更多
SrSO4：Dy,Tb nanocrystalline with crystalline size in the range of 44-54 nm was prepared by co-precipitation method followed by thermal treatment and characterized by X-ray diffraction （XRD）, scanning electron micro...SrSO4：Dy,Tb nanocrystalline with crystalline size in the range of 44-54 nm was prepared by co-precipitation method followed by thermal treatment and characterized by X-ray diffraction （XRD）, scanning electron microscopy （SEM）, energy dispersive X-ray spectroscopy （EDX） and UV-visible spectrometry. Our results provided direct evidence of incorporation of impurities into nanocrystalline SrSO4. The thermoluminescence （TL） properties of SrSOn：Dy,Tb nanocrystalline pellets irradiated with gamma rays at different doses were studied. The TL glow curve of SrSOa：Dy,Tb nanocrystalline pellets had a prominent peak at around 490 K and a small peak at around 430 K. The major peak in the TL glow curve was almost resolved from other peaks, which was analyzed using Chen＇s peak shape method to determine the TL kinetic parameters such as activation energy, E and kinetic order, b. The intensity of main dosimetric peak of SrSO4：Dy,Tb nanocrystalline pellets at around 490 K increased linearly with the increase in gamma dose. The TL response was linear in the range of 0.1-7 kGy. These properties made it a candidate as a dosimeter to be used for estimating the high dose of gamma rays.展开更多
文摘This study aimed to assess trace element concentrations in the hair of street children. Nutritional status was assessed by 24 hours’ dietary recall and anthropometric measurements. Data analysis found that Br, Sc, Sm and Ti concentrations show a normal distribution, and there is no significant difference between street children and control group. However, in the street children’s hair, the levels of Au, U, V are decreased and the levels of Co, La, Sb, Th are increased compared to the control group.
文摘SrSO4：Dy,Tb nanocrystalline with crystalline size in the range of 44-54 nm was prepared by co-precipitation method followed by thermal treatment and characterized by X-ray diffraction （XRD）, scanning electron microscopy （SEM）, energy dispersive X-ray spectroscopy （EDX） and UV-visible spectrometry. Our results provided direct evidence of incorporation of impurities into nanocrystalline SrSO4. The thermoluminescence （TL） properties of SrSOn：Dy,Tb nanocrystalline pellets irradiated with gamma rays at different doses were studied. The TL glow curve of SrSOa：Dy,Tb nanocrystalline pellets had a prominent peak at around 490 K and a small peak at around 430 K. The major peak in the TL glow curve was almost resolved from other peaks, which was analyzed using Chen＇s peak shape method to determine the TL kinetic parameters such as activation energy, E and kinetic order, b. The intensity of main dosimetric peak of SrSO4：Dy,Tb nanocrystalline pellets at around 490 K increased linearly with the increase in gamma dose. The TL response was linear in the range of 0.1-7 kGy. These properties made it a candidate as a dosimeter to be used for estimating the high dose of gamma rays.
