To understand the levels of potentially toxic elements(PTEs)contamination in soils and their effects on human health from different agricultural land use in Sanya,China.128 soil samples(64 topsoil samples and correspo...To understand the levels of potentially toxic elements(PTEs)contamination in soils and their effects on human health from different agricultural land use in Sanya,China.128 soil samples(64 topsoil samples and corresponding subsoil samples)were collected from the five representative land-use patterns.Inductively coupled plasma mass spectrometry(ICP-MS),Atomic fluorescence spectrometry(AFS),and Inductively coupled plasma optical emission spectrometry(ICP-OES)were used to determine the content of PTEs(As,Cd,Hg,Cu,Cr,Ni,Pb,Zn,Co,Mo,Sb,and V).Correlation analysis and factor analysis were used to determine the source of PTEs.Geo-accumulation index(I_(geo)),hazard quotient(HQ),and total carcinogenic risk index(TR)were used to measure the PTEs contamination and its relative health impacts.Results showed that the average values of 12 PTEs in topsoil were higher than the Hainan soil geochemical baseline,showing different degrees of PTEs accumulation effect.The concentration of PTEs in the topsoil was lower than those in the subsoil except for Cd and Hg.The I_(geo)revealed that the major accumulated element in soils was As followed by Mo.Source apportionment suggested that parent materials and agricultural practices were the dominant factors for PTEs accumulation in the topsoil.Noncarcinogenic risks of soil samples from five land-use patterns presented a trend of paddy field>dry field>woodland>orchard>garden plot.However,the HQ values of 12 PTEs were less than the recommended limit of HQ=1,representing that there are no non-carcinogenic risks of PTEs for children and adults in the study area.The TR values are within 6.95×10^(-6)-1.38×10^(-5),which corresponds to the low level.Therefore the PTEs in the agricultural soil of the study area show little influence on the health status of the local population.展开更多
为解决植入式电子医疗器械在无线能量传输(Wireless Power Transmission, WPT)时效率较低的问题,根据Pancharatnam-Barry理论设计了一种可穿戴超表面结构,利用梯度相位设计调整电磁波入射角度,使波矢量方向尽可能垂直于皮肤,从而提高体...为解决植入式电子医疗器械在无线能量传输(Wireless Power Transmission, WPT)时效率较低的问题,根据Pancharatnam-Barry理论设计了一种可穿戴超表面结构,利用梯度相位设计调整电磁波入射角度,使波矢量方向尽可能垂直于皮肤,从而提高体内受电单元的能量接收功率。这种超表面单元具有良好的极化转换效率,透射幅度达到0.8以上。为验证其合理性,搭建人体局部等效模型进行系统仿真,结果表明加入超表面后系统的传输系数提高了5 dB,并且人体内的电场强度分布也明显改善,植入天线工作区域的场强显著提高,所设计结构有效改善了植入系统的能量传输效率(Power Transfer Efficiency, PTE)。实验结果进一步验证了该设计的有效性,所提出的超表面结构具有柔性、高效和易集成等优点,为提高植入系统无线PTE提供了一种有效的解决方案。展开更多
Type 2 diabetes mellitus(T2DM)is typified by the increment of chronic blood glucose levels that is caused by an absolute and/or a relative deficiency of insulin,accounts for 90%of diabetes and causes a range of compli...Type 2 diabetes mellitus(T2DM)is typified by the increment of chronic blood glucose levels that is caused by an absolute and/or a relative deficiency of insulin,accounts for 90%of diabetes and causes a range of complications[1].展开更多
基金supported by Open Foundation of the Key Laboratory of Coupling Process and Effect of Natural Resources Elements(No.2023KFKTB001)the Science&Technology Fundamental Resources Investigation Program(2022FY101800)+2 种基金the National Nonprofit Institute Research Grant of IGGE(AS2023D01)the projects of the China Geological Survey(DD20230309 and DD20190305)the National Natural Science Foundation of China(42002105)。
文摘To understand the levels of potentially toxic elements(PTEs)contamination in soils and their effects on human health from different agricultural land use in Sanya,China.128 soil samples(64 topsoil samples and corresponding subsoil samples)were collected from the five representative land-use patterns.Inductively coupled plasma mass spectrometry(ICP-MS),Atomic fluorescence spectrometry(AFS),and Inductively coupled plasma optical emission spectrometry(ICP-OES)were used to determine the content of PTEs(As,Cd,Hg,Cu,Cr,Ni,Pb,Zn,Co,Mo,Sb,and V).Correlation analysis and factor analysis were used to determine the source of PTEs.Geo-accumulation index(I_(geo)),hazard quotient(HQ),and total carcinogenic risk index(TR)were used to measure the PTEs contamination and its relative health impacts.Results showed that the average values of 12 PTEs in topsoil were higher than the Hainan soil geochemical baseline,showing different degrees of PTEs accumulation effect.The concentration of PTEs in the topsoil was lower than those in the subsoil except for Cd and Hg.The I_(geo)revealed that the major accumulated element in soils was As followed by Mo.Source apportionment suggested that parent materials and agricultural practices were the dominant factors for PTEs accumulation in the topsoil.Noncarcinogenic risks of soil samples from five land-use patterns presented a trend of paddy field>dry field>woodland>orchard>garden plot.However,the HQ values of 12 PTEs were less than the recommended limit of HQ=1,representing that there are no non-carcinogenic risks of PTEs for children and adults in the study area.The TR values are within 6.95×10^(-6)-1.38×10^(-5),which corresponds to the low level.Therefore the PTEs in the agricultural soil of the study area show little influence on the health status of the local population.
文摘为解决植入式电子医疗器械在无线能量传输(Wireless Power Transmission, WPT)时效率较低的问题,根据Pancharatnam-Barry理论设计了一种可穿戴超表面结构,利用梯度相位设计调整电磁波入射角度,使波矢量方向尽可能垂直于皮肤,从而提高体内受电单元的能量接收功率。这种超表面单元具有良好的极化转换效率,透射幅度达到0.8以上。为验证其合理性,搭建人体局部等效模型进行系统仿真,结果表明加入超表面后系统的传输系数提高了5 dB,并且人体内的电场强度分布也明显改善,植入天线工作区域的场强显著提高,所设计结构有效改善了植入系统的能量传输效率(Power Transfer Efficiency, PTE)。实验结果进一步验证了该设计的有效性,所提出的超表面结构具有柔性、高效和易集成等优点,为提高植入系统无线PTE提供了一种有效的解决方案。
基金supported by the National Nature Science Foundation of China[No.81872626]Science and Technology Foundation for Innovation Talent of Henan Province[No.154200510010]Science and Technology Plan of Henan Province[No.172102310029]。
文摘Type 2 diabetes mellitus(T2DM)is typified by the increment of chronic blood glucose levels that is caused by an absolute and/or a relative deficiency of insulin,accounts for 90%of diabetes and causes a range of complications[1].
