目的研究马口铁包装水果罐头中锡的浓度变化和形态分布。方法采用电感耦合等离子体串联质谱法(inductively coupled plasma tandem mass spectrometry,ICP-MS/MS)测定马口铁包装水果罐头的锡含量,并分析锡浓度随储存时间、加热次数的变...目的研究马口铁包装水果罐头中锡的浓度变化和形态分布。方法采用电感耦合等离子体串联质谱法(inductively coupled plasma tandem mass spectrometry,ICP-MS/MS)测定马口铁包装水果罐头的锡含量,并分析锡浓度随储存时间、加热次数的变化特点;采用高效液相色谱电感耦合等离子体串联质谱法(high performance liquid chromatography-inductively coupled plasma tandem mass spectrometry,HPLC-ICP-MS/MS)测定并分析罐头中锡的形态分布。结果镀锡马口铁包装水果罐头中锡含量在生产日期3个月内为27.17~183.81mg/kg,生产日期12个月时为54.56~265.44mg/kg,锡浓度随储存时间、加热次数而明显增加,溶出锡为无机形态,以二价锡Sn[II]为主,未检测到锡的有机形态。结论马口铁包装水果罐头中锡随储存时间和加热次数而大量增加,但都以无机锡的形态存在,因吸收利用率低,毒性较低;尽量选择靠近生产日期的产品,且不要罐内加热食用。展开更多
The Nuri deposit is the only Cu-W-Mo polymetallic deposit with large-scale WO3 resources in the eastern section of the Gangdese metallogenic belt,Tibet,China.However,the genetic type of this deposit has been controver...The Nuri deposit is the only Cu-W-Mo polymetallic deposit with large-scale WO3 resources in the eastern section of the Gangdese metallogenic belt,Tibet,China.However,the genetic type of this deposit has been controversial since its discovery.Based on a study of the geological characteristics of the deposit,this study presents mineralization stages,focusing on the oxide stage and the quartz-sulfide stage where scheelite is mainly formed,referred to as Sch-A and Sch-B,respectively.Through LA-ICP-MS trace element and Sr isotope analyses,the origin,evolutionary process of the oreforming fluid and genesis of the ore deposit are investigated.Scanning Electron Microscope-Cathodoluminescence(SEMCL)observations reveal that Sch-A consists of three generations,with dark gray homogenous Sch-A1 being replaced by relatively lighter and homogeneous Sch-A2 and Sch-A3,with Sch-A2 displaying a gray CL image color with vague and uneven growth bands and Sch-A3 has a light gray CL image color with hardly any growth band.In contrast,Sch-B exhibits a‘core-rim’structure,with the core part(Sch-B1)being dark gray and displaying a uniform growth band,while the rim part(Sch-B2)is light gray and homogeneous.The normalized distribution pattern of rare earth elements in scheelite and Sr isotope data suggest that the early ore-forming fluid in the Nuri deposit originated from granodiorite porphyry and,later on,some country rock material was mixed in,due to strong water-rock interaction.Combining the O-H isotope data further indicates that the ore-forming fluid in the Nuri deposit originated from magmatic-hydrothermal sources,with contributions from metamorphic water caused by water-rock interaction during the mineralization process,as well as later meteoric water.The intense water-rock interaction likely played a crucial role in the precipitation of scheelite,leading to varying Eu anomalies in different generations of scheelite from the oxide stage to the quartz-sulfide stage,while also causing a gradual decrease in oxygen fugacity(fO2)and a slow rise in pH value.Additionally,the high Mo and low Sr contents in the scheelite are consistent with typical characteristics of magmatic-hydrothermal scheelite.Therefore,considering the geological features of the deposit,the geochemical characteristics of scheelite and the O-H isotope data published previously,it can be concluded that the genesis of the Nuri deposit belongs to porphyry-skarn deposit.展开更多
文摘目的研究马口铁包装水果罐头中锡的浓度变化和形态分布。方法采用电感耦合等离子体串联质谱法(inductively coupled plasma tandem mass spectrometry,ICP-MS/MS)测定马口铁包装水果罐头的锡含量,并分析锡浓度随储存时间、加热次数的变化特点;采用高效液相色谱电感耦合等离子体串联质谱法(high performance liquid chromatography-inductively coupled plasma tandem mass spectrometry,HPLC-ICP-MS/MS)测定并分析罐头中锡的形态分布。结果镀锡马口铁包装水果罐头中锡含量在生产日期3个月内为27.17~183.81mg/kg,生产日期12个月时为54.56~265.44mg/kg,锡浓度随储存时间、加热次数而明显增加,溶出锡为无机形态,以二价锡Sn[II]为主,未检测到锡的有机形态。结论马口铁包装水果罐头中锡随储存时间和加热次数而大量增加,但都以无机锡的形态存在,因吸收利用率低,毒性较低;尽量选择靠近生产日期的产品,且不要罐内加热食用。
基金financially supported by the National Key Research and Development Program of China(Grant No.2021YFC2901903)the Geological Comprehensive Research Project of China’s Metallurgical Geology Bureau(Grant No.[2022]CMGBDZYJ005),the National Natural Science Foundation of China(Grant No.42002097)the Geological Investigation Project(Grant Nos.DD20230031,DD20221690,DD20230049,DD20230337).
文摘The Nuri deposit is the only Cu-W-Mo polymetallic deposit with large-scale WO3 resources in the eastern section of the Gangdese metallogenic belt,Tibet,China.However,the genetic type of this deposit has been controversial since its discovery.Based on a study of the geological characteristics of the deposit,this study presents mineralization stages,focusing on the oxide stage and the quartz-sulfide stage where scheelite is mainly formed,referred to as Sch-A and Sch-B,respectively.Through LA-ICP-MS trace element and Sr isotope analyses,the origin,evolutionary process of the oreforming fluid and genesis of the ore deposit are investigated.Scanning Electron Microscope-Cathodoluminescence(SEMCL)observations reveal that Sch-A consists of three generations,with dark gray homogenous Sch-A1 being replaced by relatively lighter and homogeneous Sch-A2 and Sch-A3,with Sch-A2 displaying a gray CL image color with vague and uneven growth bands and Sch-A3 has a light gray CL image color with hardly any growth band.In contrast,Sch-B exhibits a‘core-rim’structure,with the core part(Sch-B1)being dark gray and displaying a uniform growth band,while the rim part(Sch-B2)is light gray and homogeneous.The normalized distribution pattern of rare earth elements in scheelite and Sr isotope data suggest that the early ore-forming fluid in the Nuri deposit originated from granodiorite porphyry and,later on,some country rock material was mixed in,due to strong water-rock interaction.Combining the O-H isotope data further indicates that the ore-forming fluid in the Nuri deposit originated from magmatic-hydrothermal sources,with contributions from metamorphic water caused by water-rock interaction during the mineralization process,as well as later meteoric water.The intense water-rock interaction likely played a crucial role in the precipitation of scheelite,leading to varying Eu anomalies in different generations of scheelite from the oxide stage to the quartz-sulfide stage,while also causing a gradual decrease in oxygen fugacity(fO2)and a slow rise in pH value.Additionally,the high Mo and low Sr contents in the scheelite are consistent with typical characteristics of magmatic-hydrothermal scheelite.Therefore,considering the geological features of the deposit,the geochemical characteristics of scheelite and the O-H isotope data published previously,it can be concluded that the genesis of the Nuri deposit belongs to porphyry-skarn deposit.