La对Pb， Cd复合污染大豆幼苗的缓解作用

以盆栽法研究了Ｐｂ，Ｃｄ复合污染对大豆幼苗的影响及Ｌａ对Ｐｂ，Ｃｄ复合胁迫的缓解效应。结果显示，Ｐｂ５００ｍｇ／Ｌ和Ｃｄ１００ｍｇ／Ｌ的混合液严重抑制大豆幼苗代谢与生长。叶面喷施３０ｍｇ／ＬＬａＣｌ３一次，能减轻Ｐｂ，Ｃｄ复合污染造成的伤害。这与Ｌａ能增加大豆幼苗光合速率，提高叶绿素含量与硝酸还原酶活性，降低质膜透性与植株中Ｐｂ，Ｃｄ含量，维持ＴＴＣ还原力等多重作用相关。     

高岭土对焚烧烟气中Pb、Cd排放的控制特性研究

采用流化床焚烧炉进行焚烧实验,研究了烟气中颗粒物形态Pb和Cd的排放规律以及炉内添加高岭土粉末对Pb、Cd排放的影响。用低压冲击器分级采集颗粒物,原子吸收分光光度计检测Pb、Cd浓度,用扫描电镜/X射线衍射/能谱仪观察高岭土吸附重金属前后表面形貌和反应物的种类并检测表面元素分布。结果表明,PM10中90%以上的Pb和85%以上的Cd分布在亚微米颗粒物中;在焚烧炉内,Pb比Cd更易于向PM10中迁移。高温下高岭土与重金属Pb、Cd蒸气反应而产生共晶融化,随温度升高融化量逐渐增加。共晶融化可以促使颗粒相互黏附,促进亚微米重金属向粗颗粒中迁移。添加高岭土可以有效控制亚微米Pb、Cd排放,对亚微米Pb的最高吸附效率达83%,对亚微米Cd的最高效率达50%。高岭土对Pb吸附效率顺序为950℃1000℃850℃900℃;高岭土与Cd反应所需的温度较高,直至1000℃时才具有明显吸附效果。     

吸附原子电催化机理的研究——铂单晶(100)晶面上Pb、Cd吸附原子在甲酸电氧化中的助催化特性

In this work a modified adsorption method was used to form firstly a saturated Cd or Pb adlayer on platinum single crystal (100) surface, then its surface structure, the electrochemical stability and the desorption-readsorption CV properties were studied. The HCOOH oxidation has been used as a probe to determine the electrocatalytic propertics of Pt (100) with different surface concentration of Cd or Pb adatoms. The results show that Cd adatoms on Pt(100) inhibit both HCOOH dissociation adsorption (to form poisoning intermediates) and HCOOH oxidation via the reactive intermediate, and that Pb adatoms on Pt(100) inhibit only HCOOH disociation adsorption but catalyse HCOOH oxidation via the reactive intermediate, in this case the more Pb adatoms on Pt(100), the higher te catalytic effect. The highest enhanced catalytic effet has been found with the saturated Pb adlayer on Pt(100) (the coverage of Pb, calibrated by hydrogen adsorption, is then equal to 1.0), i.e. with a surface structure of C(2×2)-bridged Pb. The difference of influence to the hydrogen adsorption-desorption process and the different catalytic effect on HCOOH oxidation of Cd and Pb adatoms on Pt(100) were attributed to the intrinsic properties of Cd and Pd elements and also to their interaction with Pt(100). This results indicate that the electrocatalytic mechanism of Cd and Pb adatom on Pt(100) depends on the geometrical surface structure effect and, more importantly, on the electro structure effect during the interaction of adatoms with Pt(100) surface atoms.     

La-Gly对Pb胁迫下大豆幼苗生理生化特性的影响

大豆幼苗在高剂量Ｐｂ 胁迫下, 生理生化特性发生明显改变, 其中ＭＤＡ、质膜透性、ＣＡＴ和ＰＯＤ 活性急剧上升。叶面喷布３０ ｍｇ·Ｌ－１ＬａＧｌｙ１ 次, 可缓解Ｐｂ 对大豆幼苗的伤害。这同ＬａＧｌｙ 降低植株体内Ｐｂ 含量, 增强光合作用与ＮＲ 活性, 降低ＭＤＡ含量与质膜透性, 维持保护膜（ＣＴＡ、ＰＯＤ） 活性等多重作用相关。     

LaCl3对大豆Cu, Zn-SOD活性影响研究

研究证明0～100μmol·L-1的LaCl3对于大豆Cu,Zn SOD的NBT光还原活性抑制作用具有明显影响,即受La3+作用,大豆Cu,Zn SOD活性动力学曲线为S形,同时受La3+作用Cu,Zn SOD的热稳定性明显提高。大豆Cu,Zn SOD受La3+作用的阈值浓度和饱和浓度分别为cLa3+=18μmol·L-1,cLa3+=65μmol·L-1。根据Hill系数3.9和荧光光谱分析,大豆Cu,Zn SOD分子中存在4个La3+的强结合位点。证明了La3+对Cu,Zn SOD具有明显的正协同效应。     

Pb,Cu和Zn在自然水体生物膜中铁/ 锰氧化物等组分上的富集规律

用选择性萃取法萃取天然基质采集的生物膜中的铁/锰氧化物, 考察生物膜上铁/锰氧化物对水体中Pb, Cu及Zn的富集作用. 结果表明, 锰氧化物对生物膜富集Pb起主要作用, 而铁氧化物和除铁/锰氧化物以外的以有机质为主的其它组分的作用很小; 膜上其它组分对Cu的富集贡献较大, 锰氧化物的贡献与铁氧化物的接近; 锰氧化物对Zn的富集贡献最大, 铁氧化物和其它组分的贡献比较接近. 锰氧化物对Pb, Cu及Zn的富集能力分别高于铁氧化物的富集能力, 铁氧化物和锰氧化物对3种金属富集能力的大小顺序分别是Zn>Cu>Pb和Zn>Pb≥Cu.     

酸处理对海泡石的表面及其吸附Pb(Ⅱ)、Cd(Ⅱ)的影响

离子吸附;脱镁率;比表面;酸处理对海泡石的表面及其吸附Pb(Ⅱ)、Cd(Ⅱ)的影响     

溶剂浮选法分离富集葛根中大豆甙元的研究

采用溶剂浮选法分离富集葛根中的大豆甙元。考察了浮选溶剂、氮气流速、试液pH、浮选时间及电解质（KC1）等因素对浮选效率的影响,优选出最佳浮选条件;对最佳条件下的浮选效果进行了评价,并与溶剂萃取法进行了对照,前者明显优于后者。     

Distribution of Cd and Pb in a wetland ecosystem

Cadmium and lead contents in sediments, dominant species of plants (Phargmites aus-tralis and Scripus mariquter), benthos (Helice tridens tientsinensis, llyoplax deschampsi, and Bul-lacta exarata), and waders (Calidris ruficollis) on the Eastern End of Chongming Island were measured. The results showed that, for cadmium, there are clear stratification in the sediment of reclaimed area and bio-amplification in food chain. However, for lead, a phenomenon was different. The amplification factors (AFs) for cadmium of primary producers, primary consumers, and secondary consumers were 2.59-12.38, 0.09-8.44, and 51.1, respectively. For lead, AFs of primary producers, primary consumers and the top trophic layer were 0.29-2.62, 0.06-5.62, and 7.31, respectively. Each species of macrobenthos showed different strategies to cadmium and lead. Large-sized crabs accumulated more lead, while small-sized crabs and snails accumulated more cadmium. Waders had significantly highest AFs for cadmium and lead in the study. Tha     

示波极谱同时测定金属锌中铅和镉

本文提出了在ＨＣｌ－Ｈ＿３ＰＯ＿４－ＫＣｌ底液中示波极谱同时测定金属锌中铅、镉含量的方法，检测下限铅为０．１ｍｇ／Ｌ，镉为０．０１ｍｇ／Ｌ铅、锡波形清晰，重视性好。试样中加标准回收，铅回收率为９９．２％～１００％，镉回收率为９５％～９８％，与标准方法比较，相对误差＜５％。方法准确、简便、快速，适用于金属锌中铅、镉的常规分析。     

Lamellar and three-dimensional hybrid compounds formed by cyclohexene- and cyclohexanedicarboxylates of Pb, La, and Cd

To establish factors that determine the formation of three-dimensional hybrid structures of metal dicarboxylates involving metal-oxygen-metal linkages, we have investigated metal dicarboxylates derived from 1,2-cyclohexene as well as 1,2-, 1,3-, and 1,4-cyclohexane dicarboxylic acids. Thus, we have synthesized a 1,2-cyclohexenedicarboxylate of Cd, [Cd(1,2-CHeDC)(H2O)] (I), a 1,2-cyclohexanedicarboxylate of Pb, [Pb(1,2-CHDC)] (II), and three 1,4-cyclohexanedicarboxylates of La [La2(1,4-CHDC)3(H2O)4] (III), [La3(1,4-HCHDC)2(1,4-CHDC)5(H2O)2].H2O (IV) and [La2(1,4-CHDC)3(H2O)].2.5 H2O (V) under hydrothermal conditions and determined their structures. A mixed dicarboxylate involving both 1,3- and 1,4-cyclohexenedicarboxylates of Pb, [Pb3O(1,3-CHDC)(1,4-CHDC)].0.5 H2O (VI) and a 1,4-cyclohexanedicarboxylate of Pb, [Pb(6)O(2)(1,4-CHDC)3(1,4-HCHDC)2], have also been synthesized and characterized. While the 1,2-dicarboxylates have layered structures, the 1,4-dicarboxylates and the mixed dicarboxylates possess three-dimensional structures. Interestingly, both the 1,2 and 1,4-dicarboxylates are true hybrid compounds composed of infinite M-O-M linkages. The equatorial-equatorial (e,e) conformation is adopted commonly in all these compounds, although less stable conformations are encountered occasionally. The formation of the layered and the three-dimensional structures can be understood based on the relative disposition of the two carboxylic groups, the 1,4-isomer favoring the three-dimensional structure. Based on the results of the present study along with the available literature, we conclude that in order to obtain three-dimensional hybrid structures with metal-oxygen-metal networks, it appears necessary to make use of the 1,4-cyclohexanedicarboxylic acid.     

石墨炉原子吸收分光光度法测定茵栀黄注射液及其中的铅镉

采用石墨炉原子吸收分光光度法(GFAAS),通过对波长、光谱带宽、灯电流、干燥温度、灰化温度、原子化温度的选择来确定最佳条件,直接测定经浓HNO3和H2O2消解法预处理的茵栀黄注射液及4味药材金银花、茵陈、栀子、黄芩中Pb、Cd的含量。用体积分数为0.002%柠檬酸作基体改进剂,提高了灰化温度,消除了背景干扰,改善了原子化吸收峰,提高了测定灵敏度。线性回归方程为APb=0.0033c 0.04072,相关系数为rPb=0.9991,检出限为4×10-8mg/L;ACd=0.0889c 0.2158,rCd=0.9995,检出限为2×10-9mg/L。方法回收率为99.0%～110%,相对标准偏差小于2.5%。     

Electrochemical Sensing of Pb2+ and Cd2+ Ions with the Use of Electrode Modified with Carbon-Covered Halloysite and Carbon Nanotubes

A novel voltammetric method for the sensitive and selective determination of cadmium and lead ions using screen-printed carbon electrodes (SPCEs) modified with carbon-deposited natural halloysite (C_Hal) and multi-walled carbon nanotubes (MWCNTs) was developed. The electrochemical properties of the proposed sensor were investigated by electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV), while the morphology and structure were established by scanning electron microscopy (SEM) and X-ray powder diffraction (XRD). A two-factorial central composite design (CCD) was employed to select the composition of the nanocomposite modifying the electrode surface. The optimal measuring parameters of differential pulse anodic stripping voltammetry (DPASV) used for quantitative analysis were established with the Nelder–Mead simplex method. In the analytical investigation of Cd(II) and Pb(II) ions by DPASV, the MWCNTs/C_Hal/Nafion/SPCE exhibited a linear response in the concentration range of 0.1–10.0 µmol L⁻¹ (for both ions) with a detection limit of 0.0051 and 0.0106 µmol L⁻¹ for Pb(II) and Cd(II), respectively. The proposed sensor was successfully applied for the determination of metal ions in different natural water and honey samples with recovery values of 96.4–101.6%.     

巯基棉分离富集-ICP-AES测定高盐体系中痕量的铅、镉

采用巯基棉富集分离,电感耦合等离子体原子发射光谱法（ICP-AES）测定了高盐水样中痕量的铅、镉。研究表明,pH值为7时,巯基棉同时富集铅、镉的效果最好,可成功分离基体元素,以盐酸（1.5mol/L）溶液洗脱,铅、镉的加标回收率在95.0%~105.0%,相对标准偏差RSD为3.8%~9.7%。     

ICP-MS法测定中成药中微量砷铅镉和汞

对药品中毒性较大的有害元素指标进行严格限量控制是国际通用法规的重要规定。目前,已报道的光学分析方法归纳起来有：原子吸收光谱法、电感耦合等离子体原子发射光谱法、分光光度法、荧光分析法、化学发光法。在诸多方法中ICP-AES由于检出限低,精密度高、基体效应小、线性范围宽和多元素同时测定等优点,已在中草药微量元素分析中得到广泛应用。而ICP-MS比ICP-AES检出限改善了2-3个数量级,在中药微量分析中的应用开始受到人们的重视。本文利用微波消解ICP-MS法对几种中药及中成药中的As、Pb、Cd、Hg进行了测定,结果满意。     

双硫腙修饰玻碳电极阳极溶出伏安法测定痕量镉和铅

报道了双硫腙修饰玻碳电极同时测定痕量镉和铅的电分析方法。镉和铅离子通过与电极表面的双硫腙发生螯合作用而富集在电极表面 ,同时在 -1 .2 0V(vs.SCE)还原成零价镉和铅 ,当电极电势从 -1 .2 0V向 -0 .3 0V扫描时 ,被还原的镉和铅从电极表面溶出 ,分别于 -0 .78V和 -0 .4 8V左右形成灵敏的阳极溶出峰。优化了支持电解质及pH值、双硫腙用量、富集电位及时间等实验参数。利用该修饰电极测定镉、铅的线性范围分别为 1 .0×1 0 - 8～ 2 .5× 1 0 - 6 mol L和 5 .0× 1 0 - 9～ 2 .5× 1 0 - 6 mol L。检测限分别为 5 .0× 1 0 - 9mol L和7.0× 1 0 - 1 0 mol L。该法用于实际水样中镉和铅的测定 ,平均回收率分别为 99.3 0 %和 99.5 4 %。