Humic Acids As a Scavenger of Manganese(II) and Zinc(II) in Soil Environment Using a Radiotracer Technique

The uptake of manganese(II) and zinc(II) by humic acids (HA) was investigated using a radiotracer technique in order to elucidate their ability of scavenging heavy metals released into the soil environment. Metal uptake by HA was affected by aqueous pH, in which the amounts of Mn(II) and Zn(II) associated with HA showed a similar pattern against pH. These facts indicate that interactions of Mn(II) and Zn(II) with HA would be ionic in character, and affected by properties of the carboxyl groups in HA.     

Effect of zinc on the uptake of various elements into carrot

The effect of ZnCl₂ on the uptake of Be, Na, Mn, Co, Zn, Se, Rb, Sr, Rh, Cs and lanthanoids (Ce, Pm, Gd and Lu) by carrot (Daucas carota cv. U.S. harumakigosun) was investigated. Uptake was measured using a multitracer technique which enables to acquire information about various elements under identical conditions. The amount of uptake of Rb, Cs, Sr, Mn and Co, into roots decreased with increasing concentration of ZnCl₂. On the other hand, little effect was observed for the uptake of Be, Se, Rh and lanthanoids. These results suggest that Rb, Cs, Sr, Mn and Co competed antagonistically with Zn for the binding sites of carriers in the roots, while there was no influence on the uptake of the other elements. Uptake of Se was not influenced by Cl added as ZnCl₂. It is concluded, therefore, that carrot can distinguish Se from Cl based on the physicochemical differences between these two anion species.     

Arsenate uptake and arsenite simultaneous sorption and oxidation by Fe-Mn binary oxides: influence of Mn/Fe ratio, pH, Ca2+, and humic acid

Arsenate retention, arsenite sorption and oxidation on the surfaces of Fe-Mn binary oxides may play an important role in the mobilization and transformation of arsenic, due to the common occurrence of these oxides in the environment. However, no sufficient information on the sorption behaviors of arsenic on Fe-Mn binary oxides is available. This study investigated the influences of Mn/Fe molar ratio, solution pH, coexisting calcium ions, and humic acids have on arsenic sorption by Fe-Mn binary oxides. To create Fe-Mn binary oxides, simultaneous oxidation and co-precipitation methods were employed. The Fe-Mn binary oxides exhibited a porous crystalline structure similar to 2-line ferrihydrite at Mn/Fe ratios 1:3 and below, whereas exhibited similar structures to δ-MnO(2) at higher ratios. The As(V) sorption maximum was observed at a Mn/Fe ratio of 1:6, but As(III) uptake maximum was at Mn/Fe ratio 1:3. However, As(III) adsorption capacity was much higher than that of As(V) at each Mn/Fe ratio. As(V) sorption was found to decrease with increasing pH, while As(III) sorption edge was different, depending on the content of MnO(2) in the binary oxides. The presence of Ca(2+) enhanced the As(V) uptake under alkaline pH, but did not significantly influence the As(III) sorption by 1:9 Fe-Mn binary oxide; whereas the presence of humic acid slightly reduced both As(V) and As(III) uptake. These results indicate that As(III) is more easily immobilized than As(V) in the environment, where Fe-Mn binary oxides are available as sorbents and they represent attractive adsorbents for both As(V) and As(III) removal from water and groundwater.     

Sorption of 63Ni(II) to montmorillonite as a function of pH, ionic strength, foreign ions and humic substances

Different kinds of clay minerals have been studied extensively in the removal of radionuclides from large volumes of aqueous solutions because of their high sorption capacity. Herein, the Na-montmorillonite was characterized by using XRD and FTIR in detail. The sorption of ⁶³Ni(II) from aqueous solution to montmorillonite as a function of pH, ionic strength, foreign ions, humic substances and temperature was studied by batch technique. The sorption of ⁶³Ni(II) on montmorillonite achieved equilibration quickly. The sorption of ⁶³Ni(II) to montmorillonite was strongly dependent on pH, and dependent on ionic strength at low pH and independent of ionic strength at high pH values. The sorption of ⁶³Ni(II) on montmorillonite was enhanced at low pH in the presence of humic acid (HA), while a negative effect of HA on ⁶³Ni(II) sorption was found at high pH values. At low pH values, the sorption of ⁶³Ni(II) was attributed to outer-sphere surface complexation or ion exchange, whereas the sorption was dominated by inner-sphere surface complexation at high pH values. The montmorillonite sample is a suitable material in the preconcentration of radionuclides from large volumes and the material can be used as backfill material in nuclear waste repository.     

Solvent extraction of several metal ions with mercaptotropone

Mercaptotropone was synthesized from tropone, and its acid dissociation constant (K_a) and distribution coefficient (K_D) between benze and aqueous solution were spectrophotometrically determined as 5.75 (pK_a) and 2.46 (log K_D); Extraction behaviour of Mn(II), Co(II), Ni(II), Cu(II), Zn(II), Pb(II), Cr(III), Fe(III), Y(III), and Zr(IV) with this reagent into benzene was examined. Cu(II) and Fe(III) were completely extracted from acidic solution, Mn(II), Co(II), Ni(II), Zn(II), Pb(II), and Zr(IV) were also extracted from intermediate pH region, a part of Cr(III) was extracted, but Y(III) was not extracted.     

Determination of Mn,Co, Cu,Zn, Ag,Bi, Cd,Se, Cr and Te in anatolian iron artifacts by instrumental neutron activation analysis and atomic absorption spectrophotometry

Two methods of concentration of Ag, As, Cd, Co, Cr, Cu, Fe, Hg, In, Mo, Mn, Sb, Sc, Se, W and Zn from water have been elaborated. The trace elements are preconcentrated by coprecipitation with thionalide at pH 9, 1 and 0 or by sorption on ion exchange resin Dowex 1×2 loaded with 8-hydroxyquinoline-5-sulfonic acid at pH 7.     

糙米、胚芽米、精白米中多种矿质元素和B族维生素含量的比较研究

对产自黑龙江省绥化市的同一批粳稻分别进行加工制得糙米、胚芽米和精白米,经过干灰化法或微波消解处理后,采用电感耦合等离子体发射光谱法（ICP—OES）、原子吸收光谱法（AAS）和原子荧光光谱法（AFS）测定了其中Al、As、B、Ba、Ca、Cd、Co、cr、Cu、Fe、Hg、K、Mg、Mn、Mo、Na、Ni、P、Pb、Rb、S、Se和zn共23种矿质元素的含量,,并采用高效液相色谱法（HPLC）和荧光分光光度法测定了其中维生素B．,烟酸,烟酰胺,维生素B。和维生素B：的含量。另外,还研究了经水淘洗后这3种类型大米中矿质元素和B族维生素含量的损失情况。结果表明,矿质元素和B族维生素含量呈现糙米,胚芽米,精白米由高到低的基本特征,淘洗可使各种矿质元素和B族维生素产生不同程度的损失,其中精白米中维生素B．经水淘洗后已损失殆尽。3种类型大米中cd、Cu、Mo、Ni、S、Se、Zn等元素含量差异相对较小,并且淘洗对Mo、S元素含量几乎没有影响,而cd、cu元素含量经水淘洗后反而略有增加。     

Effect of some environmental ligands on the sorption of radionuclidesby peat humin

Summary In a previous paper we studied the interaction of the radionuclides ^110mAg, ⁶⁰Co and ⁶⁵Zn with peat humin. These nuclides are among the fission or corrosion products in nuclear reactors. The aim of this paper is to study the effect of certain ligands, which are present in the environment, such as humic acid, fulvic acid, EDTA and urea, on the sorption of these radionuclides by humin. The obtained results indicated that urea has no effect on the sorption of Co and Zn by humin, and only a little in case of Ag. However, the presence of the other ligands (humic acid, fulvic acid or EDTA) leads to different decreases in the sorption of the three nuclides by humin. The results are interpreted in the light of the complex formation between ligands and the metal cations and of the strength of binding of these cations to the humin sorbent. The release of Ag⁺in the presence of different ligands was found to follow the order: humic acid>EDTA>fulvic acid>urea. In the case of both Co²⁺and Zn²⁺, the sequence is changed to be: EDTA>humic acid>fulvic acid>urea, with a higher release in the case of Zn²⁺. The results showed that cobalt is bound more strongly to humin than silver and zinc. The sulphur content of the humic fractions plays a significant role in the competition for silver and zinc.     

Multitracer study on transport and distribution of metal ions in plants

Transport and distribution of metal ions in rice and soybean plants were studied using multitracers produced by irradiating an Au target by 135 MeV/nucleon¹²C,¹⁴N, or¹⁶O ions accelerated by RIKEN Ring Cyclotron. The multitracer consisted of radioisotopes of the following elements: Be, Na, Sc, Mn, Fe, Co, Zn, Se, Rb, Sr, Y, Zr, Nb, Ag, Te, Ba, Ce, Pm, Eu, Gd, Tb, Tm, Yb, Lu, Hf, Ir, and Pt. Rice and soybean plants were grown in a nutrient solution and also on soil containing a multitracer. -ray spectroscopy of different parts of the plants showed that all the elements were more or less taken up by roots, while appreciable transport to leaves and seeds was observed only for Mn, Zn, Se, Rb, Sr, and Ba.     

三种不同品种航天稻米微量元素含量比较分析

为探讨航天育种稻米营养品质的变异,开发功能性稻米,选择了3个航天育种稻米新品种,测定其亲本及其在不同栽培条件下Fe、Zn、Cu、Mn、Se 5种元素的含量变化,并以非航天优质稻米粳籼89为对照和自身对比进行比较。结果表明,常规栽培条件下粤航一号Se含量较其亲本提高,经施用"富硒康"栽培,Se含量较常规种植提高,与对照组对比差异有高度显著意义(P0.01);常规栽培条件下航香糯Se含量较其亲本提高,经施用"富硒康"栽培,Se含量较常规种植提高,与对照组对比差异有高度显著差异(P0.01);常规栽培条件下航小占Se含量比亲本减低,对比差异有高度显著差异(P0.01),经施用"富硒康"栽培,Se含量与其亲本Se含量相近,对比差异无显著意义(P0.05);3个航天品种稻米Fe、Zn含量有减弱,与亲本对比差异有显著意义(P0.01)。可见3种不同航天稻米品质存在品种差异、处理差异,粤航一号稻米对Se的生物富集能力显著高于其它两个航天稻米品种,更适合用作开发功能稻米。     

Zinc chalcogenolate complexes as precursors to ZnE and Mn/ZnE (E = S, Se) clusters

The ternary clusters (tmeda)(6)Zn(14-x)Mn(x)S(13)Cl(2) (1a-d) and (tmeda)(6)Zn(14-x)Mn(x)Se(13)Cl(2) (2a-d), (tmeda = N,N,N',N'-tetramethylethylenediamine; x ≈ 2-8) and the binary clusters (tmeda)(6)Zn(14)E(13)Cl(2) (E = S, 3; Se, 4;) have been isolated by reacting (tmeda)Zn(ESiMe(3))(2) with Mn(II) and Zn(II) salts. Single crystal X-ray analysis of the complexes confirms the presence of the six "(tmeda)ZnE(2)" units as capping ligands that stabilize the clusters, and distorted tetrahedral geometry around the metal centers. Mn(II) is incorporated into the ZnE framework by substitution of Zn(II) ions in the cluster. The polynuclear complexes (tmeda)(6)Zn(12.3)Mn(1.7)S(13)Cl(2)1a, (tmeda)(6)Zn(12.0)Mn(2.0)Se(13)Cl(2)2a, and (tmeda)(6)Zn(8.4)Mn(5.6)Se(13)Cl(2)2d represent the first examples of "Mn/ZnE" clusters with structural characterization and indications of the local chemical environment of the Mn(II) ions. The incorporation of higher amounts of Mn into 1d and 2d has been confirmed by elemental analysis. Density functional theory (DFT) calculations indicate that replacement of Zn with Mn is perfectly feasible and at least partly allows for the identification of some sites preferred by the Mn(II) metals. These calculations, combined with luminescence studies, suggest a distribution of the Mn(II) in the clusters. The room temperature emission spectra of clusters 1c-d display a significant red shift relative to the all zinc cluster 3, with a peak maximum centered at 730 nm. Clusters 2c-d display a peak maximum at 640 nm in their emission spectra.     

Anion-exchange separation of scandium from yttrium,lanthanum, cerium and other elements in malonic and ascorbic acid media

Summary The anion-exchange behaviour of scandium was studied in malonate and ascorbate media on Dowex 2×8 colums (1.4×18 cm). It forms anionic complexes with 8% malonic acid at pH 5.0 and 5% ascorbic acid at pH 6.5. Various eluants such as mineral acids and their corresponding salts were tested eluants and their efficiencies evaluated. Scandium was separated from alkali metals, alkaline earth metals Tl(I), Hg(II) and Fe(II). It was separated from Co, Ni, Pd, Mn, Cd and Zn by selective washing of the column and from other elements by selective elution in both systems. The separation of scandium from Y, La, Ce, Pr, Nd, Sm, Gd and Dy were a remarkable feature of the method.     

Aggregation and dissolution of 4 nm ZnO nanoparticles in aqueous environments: influence of pH, ionic strength, size, and adsorption of humic acid

Metal oxide nanoparticles are used in a wide range of commercial products, leading to an increased interest in the behavior of these materials in the aquatic environment. The current study focuses on the stability of some of the smallest ZnO nanomaterials, 4 ± 1 nm in diameter nanoparticles, in aqueous solutions as a function of pH and ionic strength as well as upon the adsorption of humic acid. Measurements of nanoparticle aggregation due to attractive particle-particle interactions show that ionic strength, pH, and adsorption of humic acid affect the aggregation of ZnO nanoparticles in aqueous solutions, which are consistent with the trends expected from Derjaguin-Landau-Verwey-Overbeek (DLVO) theory. Measurements of nanoparticle dissolution at both low and high pH show that zinc ions can be released into the aqueous phase and that humic acid under certain, but not all, conditions can increase Zn(2+)(aq) concentrations. Comparison of the dissolution of ZnO nanoparticles of different nanoparticle diameters, including those near 15 and 240 nm, shows that the smallest nanoparticles dissolve more readily. Although qualitatively this enhancement in dissolution can be predicted by classical thermodynamics, quantitatively it does not describe the dissolution behavior very well.     

Chloroform extraction of ethyl xanthate complexes from sulphuric acid media

The chloroform extraction of 30 elements (Fe, Co, Ni, Zn, Cd, Ge, Sn, V, As, Sb, Bi, Cu, Ag, Au, Mn, Re, Ga, In, Tl, Se, Te, Cr, Mo, U, Pt, Pd, Rh, Ir, Ru and Ce) from 0.1-8M sulphuric acid in the presence of potassium ethyl xanthate has been studied. Pd(II), Bi, As(III), Sb(III), Se(IV) and Te(IV) are completely extracted and Au(III) is largely extracted over the range of acid concentration investigated. Fe(II), Tl(I), Rh(III) and Cr(VI) are only slightly extracted and Se(VI), Te(VI), Ru(III), Cr(III), Mn(II), Zn, Ce(IV), Ir(IV) and Ge(IV) are not extracted at all. Depending on the acid concentration, the remaining elements are all partly extracted. Results are compared with those obtained in an earlier study of the extraction of xanthate complexes from hydrochloric acid media. The processes involved in the formation of some xanthate complexes and potential analytical separations are discussed.     

肿瘤和微量元素的关系

采用量子共振检测仪测定了２５例恶性肿瘤患者、２５例良性肿瘤者和２５例无肿瘤人头发中Ｚｎ、Ｃｕ、Ｍｎ、Ｓｅ的含量。结果表明,恶性肿瘤患者头发中的锌含量明显高于良性肿瘤患者（Ｐ〈０．００１）和无肿瘤人（Ｐ〈０．００１）,而Ｓｅ、Ｍｎ、Ｃｕ的含量明显低于良性肿瘤患者和无肿瘤人（Ｐ〈０．００１）。恶性肿瘤患者锌含量过高,而Ｓｅ、Ｍｎ、Ｃｕ含量过低,所以高锌是诱发癌症的危险因素,也是诱发良好肿瘤的因素,而Ｓ     

克山病病区和常硒及低硒非病区儿童发铜,锌,铁,锰含量的测定

用原子吸收光谱法测定了克山病病区,常硒非病硒非病区儿童区Ｃｕ、Ｚｎ、Ｆｅ、Ｍｎ含量,结果表明：（１）低硒非病区组儿童发Ｃｕ、Ｚｎ、Ｆｅ、Ｍｎ含量与常硒非病区组无明显差异。（２）克山病病区组儿童ｕ、Ｚｎ、Ｍｎ民低硒和常硒非病区组儿童无明显差异。     

隐蔽剂在螯合滴定中的应用(Ⅹ)——丙二酸可作为铝的专属性隐蔽剂

本文从理论和实践上证明了以环己烷二胺四乙酸(DCTA)为滴定剂,丙二酸在pH5.5可作为铝的专属性隐蔽剂,在以DCTA-丙二酸隐蔽法间接滴定铝时,锆、钍、锡、钛、铁、镓、稀土、铜等卅种离子不干扰。试以此法测定硅酸盐或铝青铜的铝时,进一步证明丙二酸的良好性能。     

大孔型腐植酸树脂的合成及其对重金属离子的螯合性

交联的聚苯乙烯(PS)通过偶氮键—N=N—或酯、醚键与腐植酸(HA)相连接枝得珠状大孔型腐植酸树脂(HAR)。当HA/PSNH_2的重量比为0.7—1.0,PSN_2~+Cl~-偶联PH13时制得的偶氮型腐植酸树脂(AHAR)对重金属离子有优良的吸附性。延长PSCH_2Cl与HA的反应时间可提高酯醚型腐植酸树脂(EHAR)对Cu~(2+)的吸附量。红外光谱探讨了HAR的结构。AHAR的吸附容量为1.01mmol~(2+)Cd/g树脂,对Ni~(2+)、Mn~(2+)、Cu~(2+)、Co~(3+)、Zn~(2+)为0.6—0.53mmol离子/g树脂。重金属离子在AHAR上的分配系数为 Cu~(2+)(8.7×10~3)>Cd~(2+)(3.8×10~2)>Zn~(2+)(2.4×10~2)>Ni~(2+)(1.8×10~2)>Mn~(2+)(4.9×10)。 pH6.5时AHAR能定量吸附Cu~(2+)、Cd~(2+)、Ni~(2+)、Mn~(2+),并能用INHNO_3定量洗脱。AHAR可再生,重复使用,分析了四种天然水、自来水中痕量上述金属离子的浓度。     

Simultaneous biobehavior of trace elements, Sc, Mn, Fe, Co, Zn, Se, Rb and Zr in the brain and other organs of C57BL/6N mice

The radioactive multitracer technique was applied to a study on the uptake of trace elements in normal C57BL/6N mice. Comparative uptake behavior of⁴⁶Sc,⁵⁴Mn,⁵⁹Fe,⁵⁸Co,⁶⁵Se,⁸³Rb and⁸⁸Zr tracers was examined among 11 organs (brain, cardiac muscle, lung, liver, spleen, pancreas, kidneys, bone, muscle, eyeballs and testes) and blood, and evaluated in terms of the “tissue uptake rate (the radioactivity percentage of injected dose per gram of tissue, %dose/g)”. The multitracer technique revealed reliable data demonstrating characteristic uptake of the 8 trace elements, Sc, Mn, Fe, Co, Zn, Se, Rb and Zr by the brain and other organs, as well as the distinctive features of the accumulation and retention of each element in the brain.     

108例甲状腺功能障碍患者全血9种元素相关性研究

通过原子吸收光谱技术对68例治疗前甲亢病人(A组)，35例治疗后甲亢病人(B组)，5例甲减病人(C组)及74例正常人(D组）全血多种微量元素测定分析，结果显示：D组Cu与Al，Mg与Mn正相关；Al与Zn、Se负相关；A组Fe与Zn、Ca，Ca与TT4。Cu与Mn正相关，TT与Zn、Cr负相关。B组Fe与Zn、Cu、Mg，Zn与Cu、Mn、Mg与Ca、Se、Se与TT3正相关。