GF-AAS法测定庐山区农村饮用水中铅、镉的含量

通过对庐山区农村饮用水进行抽样测定了重金属Pb、Cd的含量,分析重金属Pb、Cd的污染情况。选取有代表性的水样28份,采用石墨炉原子吸收光谱法(GF-AAS)测定饮用其中Pb、Cd的含量。结果表明:28份水样中所含Pb量为(0.2386±0.4124)μg/L,Cd量为(0.0984±0.1456)μg/L。根据《生活饮用水卫生标准》(GB/T5750-2006),Pb限度为10μg/L,Cd限度为5μg/L,28份样本所测的重金属均在其限度范围内,表明庐山区农村饮用水没有重金属Pb、Cd的污染。     

铅在土壤-蔬菜体系中的迁移规律

采集中山市农田中的土壤及对应种植的蔬菜,测定土壤和蔬菜中铅的含量,并计算出不同蔬菜对土壤中铅的富集系数,进而分析土壤中的铅含量、蔬菜中铅含量与蔬菜铅富集系数的相关性情况,以研究铅在土壤-蔬菜体系中的迁移规律。结果表明:不同蔬菜中铅含量差异明显,铅在土壤-蔬菜体系中的迁移能力因蔬菜种类不同而不同,蔬菜中铅含量与土壤中铅含量不具显著相关性,与其富集系数具显著相关性。     

Identification and Functional Analysis of MicroRNAs and Their Targets in Platanus acerifolia under Lead (Pb) Stress

MicroRNAs (miRNAs) play important regulatory roles in development and stress responses in plants. Lead (Pb) is a non-essential element that is highly toxic to living organisms. Platanus acerifolia is grown as a street tree in cities throughout temperate regions for its importance in improving the urban ecological environment. MiRNAs that respond to abiotic stresses have been identified in plants; however, until now, the influence of Pb stress on P. acerifolia miRNAs has not been reported. To identify miRNAs and predict their target genes under Pb stress, two small RNA and two degradome libraries were constructed from Pb-treated and Pb-free leaves of P. acerifolia seedlings. After sequencing, 55 known miRNAs and 129 novel miRNAs were obtained, and 104 target genes for the miRNAs were identified by degradome sequencing. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway analyses were performed to predict the functions of the targets. The expressions of eight differentially expressed miRNAs were validated by quantitative real-time polymerase chain reaction (qRT-PCR). This is the first report about P. acerifolia miRNAs and their target genes under Pb stress. This study has provided data for further research into molecular mechanisms involved in resistance of P. acerifolia to Pb stress.     

辽东青城子姚家沟钼矿床S、Pb同位素组成及其地质意义

本文对辽东青城子姚家沟钼矿床金属硫化物进行S、Pb同位素测量,探讨成矿物质来源。研究结果表明,金属硫化物δ34S值变化介于2.0‰～3.9‰之间,显示岩浆硫的特点。矿石206Pb/204Pb=17.708～18.854,207Pb/204Pb=15.474～15.669,208Pb/204Pb=37.739～39.097。铅同位素Th/U比值范围为3.74～3.94,μ值介于9.34～9.56之间,均低于9.58 介于地壳与原始地幔值之间,反应矿石铅具深源铅和壳源铅特征,铅同位素特征参数、判别图解结合矿床成矿背景和矿床成因,认为姚家沟钼矿铅同位素组成具混合铅特征,这种混合受俯冲造山作用控制,是一种与岩浆作用有关的壳幔混合铅的成矿作用。     

论西塔里木晚古生代弧形海相热水-火山热水沉积型铅锌（铜）矿区域成矿特征

西塔里木弧形晚古生代海相热水-火山热水沉积铅锌(铜)矿的蕴矿基础是恰尔隆-库尔良拉张坳陷带的一部分,奥依塔格裂陷槽,和西南天山柯坪断隆外缘(木兹都克)构造过渡带.这个弧形矿带的亚一级构造是弧顶区昆盖山北坡裂谷,属古隆外缘拉张坳陷带,产海相火山热水沉积型S、Cu、Zn、Au矿.弧西区塔木-卡兰古坳拉槽(夭折裂谷)产海相热水沉积型Pb、Zn(Cu)矿.弧东区西南天山木兹都克构造过渡带,产海相热水-火山热水沉积型Pb、Zu、Cu矿.这个弧形矿带中的矿产,其成矿与控矿构造具有一致性,成矿时代具有相对集中性、矿产生成具有迁移性、区域成矿特征具有可对比性,是新疆最为重要的铅锌成矿区带.     

微波消解-石墨炉法测定缢蛏中的铅

铅的检测方法归纳起来有原子吸收光谱法、电感耦合等离子体原子发射光谱/质谱法、分光光度法等。本文研究了硝酸-双氧水体系对缢蛏样品微波消解石墨炉原子吸收分光光度法测定缢蛏中的铅的方法,基体改进剂为磷酸二氢胺溶液(20g/L),塞曼扣背景,结果表明本方法简便、精密度好、准确性高。方法检测限为0.017mg/kg,实际样品回收率为80.0%~98.0%。精密度和重现性均能满足试验要求。     

浅析退锡铅制程

文章主要介绍退锡铅制程的原理、制程问题的解决方法以及设备的设计的注意事项。     

Removal, preconcentration and determination of trace heavy metal ions in water samples by AAS via chemically modified silica gel N-(1-carboxy-6-hydroxy) benzylidenepropylamine ion exchanger

The use of chemically modified silica gel N-(1-carboxy-6-hydroxy) benzylidenepropylamine (SiG-CHBPA), ion exchanger for removal and preconcentration of Cr, Mn, Fe, Co, Ni, Cu, Zn, Cd and Pb in natural water samples collected from River Nile, Mediterranean Sea and other locations followed by their consecutive AAS determination was described. The effects on the percentage of recovered metal ions including mass change of ion exchanger, stirring time, pH of sample solutions and eluent concentration were studied. The distribution coefficient K_d, ml g^− 1 and the percentage concentration of the studied metal ions on the ion exchanger at equilibrium, C_M,_eqm ,% (Recovery, %) were studied as a function of experimental parameters. The logarithmic values of the distribution coefficients, log K_d are 3-6.3. The interfering effects of some foreign ions on the removal, preconcentration and determination of the investigated metal ions were described. The metal-chelates formed between the ion exchanger and the studied metal ions were characterized by IR (absorption and reflectance), UV spectrometry, potentiometric titration and thermal analysis (TG and DTG). The reliability of the present method was confirmed by the comparison with a standard solvent extraction method. The present method is simple and rapidly applicable for the determination of the studied metal ions, ng ml^− 1 in different natural water samples.     

有机高分子螯合剂在氰化废水治理中的应用研究

用一种新型有机高分子螯合剂处理含氰废水中的Pb2+、Hg2+等重金属离子,对其处理效果与无机沉淀剂Na2S进行了比较。结果表明,该螯合剂对氰化废水中的Pb2+、Hg2+等重金属离子的捕集效率高,处理后的废水可排放,且成本低、设备简单。     

大兴安岭东南段哈拉苏西铅锌多金属矿床地质特征及成因探讨

大兴安岭东南段晚侏罗世—早白垩世火山—岩浆活动强烈,形成了以北北东向构造控制的构造岩浆岩带,发现多处与其相关的铅锌银矿床。在充分收集已有地质、物探和化探资料的基础上,分析了哈拉苏西铅锌多金属矿矿区和矿体地质特征,提出了矿床成因机制和找矿方向。研究为大兴安岭东南段与火山—岩浆作用相关中低温热液型金属矿的发现提供了基础地质资料和勘查找矿思路。