Application of Modified Nickel Slag Adsorbent on the Removal of Pb~(2+) and Cu~(2+) from Aqueous Solution

Al(OH)_3 modified nickel slag adsorbent was prepared by sintering technology. The structure of the sample was characterized by BET, XRD, IR, SEM and EDAX. The sample's adsorption performance of Pb~(2+) and Cu~(2+) from aqueous solution was studied. Results indicated that the adsorbent is a loose and porous mesoporous material. Its surface had mass aluminosilicate, high-activity γ-Al_2O_3 and its p H ranges from 4 to 12 that all have negative charges. The BET surface of the adsorbent is 23.90 m~2/g. Furthermore, its surface contains rich oxygenic functional groups, which could not only provide abundant adsorption sites for Pb~(2+) and Cu~(2+), but also improve the adsorption performance of Pb~(2+) and Cu~(2+) from waste water through the complexation of heavy metal ions. The best p H values selected in the adsorption of Pb~(2+) and Cu~(2+) are 6 and 5, respectively. With the increase of the initial concentration of simulated solution, the adsorption capacities of Pb~(2+) and Cu~(2+) gradually increased but the removal rates showed a downward trend. The competitive adsorption results of Pb~(2+) and Cu~(2+) showed that Pb~(2+) has better preferential adsorption than Cu~(2+).     

液相色谱柱后衍生法同时测定Pb~(2+)Cu~(2+)Cd~(2+)Co~(2+)Zn~(2+)和Ni~(2+)

采用液相色谱流动相为0.05mol·L~(-1)草酸和0.095mol·L~(-1)氢氧化锂,流速为1.0ml·min~(-1);柱后衍生试剂为0.001mol·L~(-1)PAR+0.3mol·L~(-1)氨水+0.1mol·L~(-1)乙酸,流速为1.0ml·min~(-1),进样体积为20μl,检测波长为500nm,同时对Pb~(2+)、Cu~(2+)、Cd~(2+)、Co~(2+)、Zn~(2+)和Ni~(2+)检测。方法可用于水样检测。     

离子色谱法测定水中钙和镁

水的硬度测定,通常采用EDTA滴定法,文中改用离子色谱法测定,一次进样后同时测定水样中mg.L^-1级的钙和镁,然后换算成以mg.L^-1,硕酸钙表示的硬度,方法的回民率在98．2－102．0％之间,相对标准偏差为0．94％－1．21％,具有简便,快速,准确的特点。     

基于胸腺嘧啶-汞离子-胸腺嘧啶结构和纳米金放大传感器检测汞离子

利用Hg2+与DNA中胸腺嘧啶(T)结合的高度特异性和纳米金在石英晶体微天平(QCM)上的信号放大作用,设计了一种简便灵敏的Hg2+检测方法.纳米金采用柠檬酸钠还原法制备,其表面用末端带巯基的寡核苷酸探针进行自组装修饰,并用6-巯基己-1-醇(MCH)部分取代表面探针,以减少杂交空间位阻.结果表明,寡核苷酸链长为9bp、T个数为7的序列具有较高灵敏度;线性范围为5.0～100 nmol/L;检出限为2.0 nmol/L;Ca2+、Mg2+等其它金属离子无明显干扰.用于环境水样中Hg2+的测定, RSD<2.9%;加标回收率为97.3%～101.2%     

Eu^2＋和Mn^2＋在Sr3MgSi2O8中的光致发光研究

研究了Ｅｕ＾２＋和Ｍｎ＾２＋共激活的Ｓｒ３ＭｇＳｉ２Ｏ８的荧光性质。Ｅｕ＾２＋和Ｍｎ＾２＋在４６０ｎｍ和６９０ｎｍ的发射峰分别由Ｅｕ＾２＋的５ｄ→４ｆ跃迁和Ｍｎ＾２＋的＾４Ｔ１（＾４Ｇ）→＾６Ａ１ｇ（＾６Ｓ）跃迁产生。未观察到单掺杂Ｍｎ＾２＋的Ｓｒ３ＭｇＳｉ２Ｏ８的荧光发射，而掺入Ｅｕ＾２＋后则出现了Ｍｎ＾２＋的６９０ｎｍ光致发光峰，表明Ｅｕ＾２＋对Ｍｎ＾２＋有敏化作用。Ｅｕ＾２＋的荧光寿命也受Ｍ     

金属离子Cu~(2+)，Co~(2+)，Ni~(2+)的微芯片电泳分离及化学发光检测

根据流动注射－化学发光的通用实验装置图，设计并通过标准光刻技术，湿化 学刻蚀及热键合技术制作了玻璃微芯片。在该芯片上将毛细管电泳分离与化学发光 检测相联用，鲁米诺和H_2O_2化学发光反应溶液通过实验室自制的微流泵输送。对 所用电压，缓冲溶液和发光试剂流速等实验条件进行了优化。在所选的最佳条件下 ，成功地实现了金属离子Cu~(2+)，Co~(2+)，Ni~(2+)的电泳分离－化学发光检测， 过渡金属离子。     

Cu(2+) and Pt(2+) complexes of pyrazole and triazole based dinucleating ligands

A series of pyrazole and triazole based dinucleating ligands have been synthesized and their complexation potential for metal ions, which exhibit square planar coordination geometry has been studied. In the case of Cu(2+) the complexation equilibria in solution have been determined using pH titrations. Species with 1 : 1 stoichiometry [CuLH(n)], 2 : 1 stoichiometry [Cu(2)LH(m)], and of dimeric nature [Cu(2)L(2)H(p)], have been detected and their overall stability constants have been measured. The reactivity of the dinuclear species [Cu(2)LH(-1)] towards phosphate ester hydrolysis have shown that the OH-functionality incorporated in some of the ligands does not enhance the hydrolysis rate. Several ligands were reacted with Pt(2+) to give insoluble dinuclear species [Pt(2)LI(3)]. One of them was studied by X-ray diffraction and shows that the two Pt(2+) are bridged by the pyrazolide group and by one I(-). The remaining two positions are occupied by the amino group in alpha position of the heterocyclic ring and a terminal I(-). The nearly planar [Pt(2)LI(3)] units form sheets in the crystals, which are about 4 A apart and thus indicate pi stacking interactions.     

Theoretical study on the Co~(2+)OH_2/Co~(3+)OH_2 electron transfer reactivity

This paper presents a contact distance dependence analysis scheme and an ab initio calculation application for the electron transfer (ET) reactivity of Co2+OH2/Co3+OH2 reacting pair. The applicability of these schemes and the corresponding models has been discussed. The contact distance (Rcoco) dependence of the relevant quantities has been analyzed. The results indicate that the activation energy from the accurate PES method agrees well with that from the anharmonic potential method, and they are obviously better than that from the harmonic potential method. The pair distribution function varies from 10~(-2) to 10~(-5) along with Rcoco changing from 1.20 to 0.35 nm. The coupling matrix element exponentially decays along with the increase of Rcoco, and the effective electronic coupling requires Rcoco smaller than 0.75 nm. In the range from 0.50 to 0.75 nm for Rcoco, the corresponding electronic transmission coefficient falls within 1.0-10~(-6). The local ET rate also exponentially decays along with the incre     

Concerning the photophysical properties of Re2(4+) and Re2(6+) carboxylate compounds

The preparation and structure of Re(2)(dppm)(2)(O(2)CC(6)H(4)-p-NO(2))(2)Cl(2), where dppm = Ph(2)PCH(2)PPh(2), is reported together with its photophysical properties (absorption, steady state emission, fs- and ns-transient absorption spectroscopy) and electrochemistry. These data are compared with photophysical studies on the previously reported Re(2)(dppm)(2)(O(2)CCH(3))(2)Cl(2). The preparation of the complex Re(2)(O(2)CC(6)H(4)-p-NO(2))(4)Cl(2) is also reported together with its photophysical properties which allows for a comparison of the electronic structures and photophysical states of Re(2)(4+) and Re(2)(6+) containing complexes having MM configurations σ(2)π(4)δ(2)δ(*2) and σ(2)π(4)δ(2), respectively. An interesting comparison is also made with the related MM quadruply bonded complexes of molybdenum and tungsten.     

Gas-phase oxidation reactions of Ta2+: synthesis and properties of TaO(2+) and TaO2(2+)

Gas-phase reactions of Ta(2+) and TaO(2+) with oxidants, including thermodynamically facile O-atom donor N(2)O and ineffective donor CO, as well as intermediate donors C(2)H(4)O (ethylene oxide), H(2)O, O(2), CO(2), NO, and CH(2)O, were studied by Fourier transform ion cyclotron resonance mass spectrometry. All oxidants reacted with Ta(2+) by electron transfer yielding Ta(+), in accord with the high second ionization energy of Ta (ca. 16 eV). TaO(2+) was also produced with N(2)O, H(2)O, O(2), and CO(2), oxidants with ionization energies above 12 eV; CO reacted only by electron transfer. The following charge separation products were also observed: TaN(+) and TaO(+) with N(2)O; and TaO(+) with O(2), CO(2), and CH(2)O. TaOH(2+), formed with H(2)O, reacted with a second H(2)O by proton transfer. TaO(2+) abstracted an electron from N(2)O, H(2)O, O(2), CO(2), and CO. Oxidation of TaO(2+) by N(2)O was also observed to produce TaO(2)(2+); on the basis of density functional theory (DFT) results, this species is a dioxide, {O-Ta-O}(2+). TaO(2)(2+) reacted by electron transfer with N(2)O, CO(2), and CO to give TaO(2)(+). Additionally, it was found that TaO(2)(2+) oxidizes CO to CO(2) and that it acts as a catalyst in the oxidation of CO by N(2)O. TaO(2)(2+) also activates H(2) to form TaO(2)H(2+). On the basis of the rates of electron transfer from N(2)O, CO(2), and CO to Ta(2+), TaO(2+), and TaO(2)(2+), the following estimates were made for the second ionization energies of Ta, TaO, and TaO(2): IE[Ta(+)] = 15.8 ± 0.3 eV, IE[TaO(+)] = 16.0 ± 0.5 eV, and IE[TaO(2)(+)] = 16.9 ± 0.4 eV. These IEs, together with recently reported bond dissociation energies, D[Ta(+)-O] and D[OTa(+)-O], result in the following bond energies: D[Ta(2+)-O] = 657 ± 58 kJ mol(-1) and D[OTa(2+)-O] = 500 ± 63 kJ mol(-1), the first of which is in good agreement with the value obtained by DFT.     

Hydrazinium(1+) hexafluorogermanate(IV) and hydrazinium(2+) hexafluorogermanate(IV) difluoride

(N₂H₅)₂GeF₆ and (N₂H₆)₂(GeF₆)F₂ have been prepared by reactions of N₂H₄·H₂O and N₂H₆F₂ with fluorogermanic acid. The solids have been characterized by chemical analysis and vibrational spectra. X-ray diffraction study has shown that crystals of (N₂H₅)₂GeF₆ are monoclinic, space group P 2₁/n, with unit-cell dimensions a = 6.015 (2), b = 5.249 (1), c = 11.181 (2) Å, β = 100.15 (2)^o, and Z = 2. There are N₂H₅⁺ cations and GeF₆^2? anions in the crystals interconnected by hydrogen bonds of the type NH····F and NH····N.     

TiO2负载Co2+、Cu2+催化剂的制备及其对甲酚催化氧化性能

用浸渍法制备了一系列以TiO2为载体的负载型催化剂,利用XRD和IR分析测试技术研究了负载Co2+与Cu2+后催化剂的表面结构,催化剂用于对甲酚氧化制备对羟基苯甲醛的反应中。 结果表明,n(Co2+)∶n(Cu2+)=1∶0.5时,催化剂的催化效果最佳。 在反应优化条件下,对甲酚的转化率可达100%,对羟基苯甲醛的选择性达95.2%。     

1H and (113)Cd NMR Investigations of Cd(2+) and Zn(2+) Binding Sites on Serum Albumin: Competition with Ca(2+), Ni(2+), Cu(2+), and Zn(2+)

1H and (113)Cd NMR studies are used to investigate the Cd(2+) binding sites on serum albumin (67 kDa) in competition with other metal ions. A wide range of mammalian serum albumins possess two similar strong Cd(2+) binding sites (site A 113-124 ppm; site B 24-28 ppm). The two strong sites are shown not to involve the free thiol at Cys34. Ca(2+) influences the binding of Cd(2+) to isolated human albumin, and similar effects due to endogenous Ca(2+) are observed for intact human blood serum. (1)H NMR studies show that the same two His residues of human serum albumin are perturbed by Zn(2+) and Cd(2+) binding alike. Zn(2+) displaces Cd(2+) from site A which leads to Cd(2+) occupation of a third site (C, 45 ppm). The N-terminus of HSA is not the locus of the two strong Cd(2+) binding sites, in contrast to Cu(2+) and Ni(2+). After saturation of the N-terminal binding site, Cu(2+) or Ni(2+) also displaces Cd(2+) from site A to site C. The effect of pH on Cd(2+) binding is described. A common Cd(2+)/Zn(2+) binding site (site A) involving interdomain His residues is discussed.     

The effect of triethylenetetraamine (Trien) on the ion flotation of Cu(2+) and Ni(2+)

Ion flotation is a separation process involving the adsorption of a surfactant and counterions at an air/aqueous solution interface. It shows promise for removing toxic heavy metal ions from dilute aqueous solutions. Here we report the effect of a neutral chelating ligand, triethylenetetraamine (Trien), on the ion flotation of cations with dodecylsulfate, DS(-), introduced as sodium dodecylsulfate, SDS. Ion flotation in the aqueous SD-Cu(II)-Ca(II)-Trien system gave strongly preferential removal of Cu(II) over Ca(II), which is a reversal of the order of selectivity seen in the SDS-Cu(II)-Ca(II) system containing no Trien. The removal rates of Cu(2+) and Ni(2+) with DS(-) were much faster in the presence of Trien than for simple aquo ions, and the final metal concentration was significantly lower. Surface tension measurements showed that Trien enhanced the surface activity and adsorption density for SDS-Cu(II) and SDS-Ni(II) solutions. The overall change in the Gibbs free energy for adsorption resulting from complexation was -3.60 kJ/mol for Cu(II) and -3.50 kJ/mol for Ni(II). This included the effects of hydrophobic interactions between the metal-Trien complexes at the air/solution interface, along with changes in the amount of dehydration associated with cosorption of the metal-Trien complex with DS(-) at the air/solution interface.     

Eu~(2+),Mn~(2+)共激活碱土镁硅酸盐基红色荧光粉的发光性能

制备了以R3MgSi2O8(R=Ba,Sr,Ca)为基,Eu2+,Mn2+共激活的红色荧光粉并研究了其荧光性质。分别以Ba3MgSi2O8,Sr3MgSi2O8,Ca3MgSi2O8为基质时,由于晶体场环境不同,发光强度、发射峰产生相应变化。研究了以(Ba,Sr)3MgSi2O8为基的荧光粉中Ba,Sr相对量,及Eu2+,Mn2+浓度对发光性质的影响并探讨了Eu2+,Mn2+在基质中所处格位;结果表明,红光是由基质中处于九配位的Eu2+将能量传递给八面体六配位的Mn2+,而由Mn2+所发射的。     

在空气中合成MBPO5:Eu2+和MBPO5:Yb2+(M=Ca,Sr,Ba)荧光体

以含RE₂O₃(RE=Eu, Yb)为起始物, 在空气中成功地合成了MBPO5:RE(²⁺)(M=Ca, Sr, Ba;RE(²⁺)=Eu(²⁺), Yb(²⁺))荧光体, 测定了它们的激发和发射光谱峰位以及发射半高宽.