Selective transport of silver ions through bulk liquid membrane using Victoria blue as carrier

Transport of Ag⁺ as Ag(CN)₂⁻ ions through a bulk liquid membrane is reported. The bulk liquid membrane used is a solution of Victoria blue (VB) in chloroform. The effects of pH of the source phase, cyanide concentration in the source phase, sodium hydroxide in the receiving phase, and VB concentration in the organic phase on the efficiency of the transport system were studied. The above system has a high selectivity for Ag⁺ and can selectively and efficiently transport Ag(CN)₂⁻ ion from aqueous solutions containing other cations such as alkali and alkaline earths, Zn²⁺, Pd²⁺, Cu²⁺, Cd²⁺,Hg²⁺, Co²⁺, Fe²⁺, Pb²⁺, Ni²⁺, and Al³⁺.     

A highly selective chemosensor for copper ion based on ICT fluorescence

Simple structural compounds 1 to 3 were synthesized.The presence of Cu²⁺ resulted in the fluorescence and absorption spectra change of 1 and 2,which indicated that 1 and 2 showed a highly selective response to Cu²⁺ over other metal ions.However,3 showed no selectivity for metal ions,which means that the compound could bind with several metal ions,such as,Ni²⁺,Zn²⁺,Cd²⁺.Hg²⁺, Pb²⁺,Fe³⁺,Mg²⁺,Ca²⁺,and Co²⁺,except Cu²⁺ and Ag⁺.The different spectral responses were attributed to the difference in binding sites for 1 and 3.     

N,N-二甲基吡啶苯甲醛缩对二甲氨基苯甲酰腙的合成及对Cu2+的选择性识别

设计合成了可用于识别铜离子的化合物N,N-二甲基吡啶苯甲醛缩对二甲氨基苯甲酰腙(1), 通过¹H NMR, ¹³C NMR和MS等对其结构进行了表征; 采用荧光光谱和吸收光谱法研究了化合物1与金属离子间的相互作用. 结果表明, 化合物1对Cu²⁺ 呈现良好的选择性, Cu²⁺ 的加入使化合物1的荧光强度增强12.5倍, 加入其它金属离子如Fe³⁺, Zn²⁺, Pb²⁺, Hg²⁺, Cd²⁺, Co²⁺, Ni²⁺, Li⁺, K⁺, Ca²⁺, Mg²⁺ 和 Ag⁺, 仅引起化合物1荧光强度的微降. 采用双倒数线性回归拟合法计算可知, 化合物1与Cu²⁺ 形成了1: 1型强发光配合物, 结合常数为2.0×10⁷ L/mol.     

碘化钾-十六烷基三甲基溴化铵-水体系液固分离银的研究

本文利用碘化钾-十六烷基三甲基溴化铵-水微晶吸附体系研究了银离子的液固分离行为.分别考察了KI用量、CTMAB用量、溶液酸度、盐和放置时间对分离效率的影响,结果表明,当2％碘化钾溶液溶液和2.0×10-3 mol·L-1 CTMAB溶液的用量均为1.0 mL时,Ag+、I-、CTMAB+形成的三元缔合物AgI2-·CT...     

Pb2+和Zn2+对亲水型光敏热成像材料感光性能和存储稳定性能的影响

分别研究了Pb²⁺和Zn²⁺对以聚乙烯醇(PVA)为粘合剂的亲水型光敏热成像(PTG)材料的感光性能以及老化稳定性能的影响.实验结果表明,涂布液中加入Pb²⁺或Zn²⁺后,PTG材料的热显影灰雾和相对感光度均明显降低,并且随着离子加入量的增加,下降程度更加显著.另外,含有Pb²⁺或Zn²⁺的PTG材料在经过不同时间的老化后,与未老化PTG材料相比,其热显影灰雾缓慢增加,相对感光度也略有上升.     

Ag+存在下催化还原铬黑T及应用于Ag+检测

以铬黑T(EBT)为探针,在有Ag⁺存在的最优条件下,EBT被NaBH 4催化还原,体系在445 nm发射波长处荧光强度明显增强,基于此构建一种光学测定溶液中微量Ag⁺的方法。在最优条件下,Ag⁺浓度在(7.5×10-9~1.0×10^-6 mol·L^-1)范围内呈良好的线性关系,线性回归方程为ΔI F=5.59×10⁸ c-31(c,mol·L^-1,r=0.9966),Ag⁺的最低有效检测浓度为6.0×10^-8 mol·L^-1。在最优条件下,运用该方法对样品中Ag⁺浓度进行检测,样品中Ag⁺浓度的检测回收率在98.8%~102.4%之间,RSD=2.1%。该检测方法能够对水溶液中微量的Ag⁺进行有效定量检测,且操作简单、检测限低、灵敏度高。     

A Highly Selective Fluorescent Chemosensor for Cu2+

A new Zn²⁺ probe L2-Zn(L2=naphthofuran carbonylhydrazone derivant) was synthesized as a fluorescence chemosensor for Cu²⁺, by which Cu²⁺ ion could be detected with high selectivity and sensitivity in a wide pH range via a displacement “turn-off” signaling strategy. Whereas the coordination between Zn²⁺ and L2 resulted in a considerable enhancement of typical luminescence of a naphthalofuran group in complex L2-Zn, the addition of Cu²⁺ ion led to a dramatic decrease in the emission intensity of probe L2-Zn at about 503 nm(excitation at 423 nm). The competitive fluorescent experiments showed that other metal ions, such as Hg²⁺, Fe³⁺, Ag⁺, Ca²⁺, Co²⁺, Ni²⁺, Cd²⁺, Pb²⁺, Zn²⁺, Cr³⁺ and Mg²⁺ could not impact the detection of Cu²⁺. The detection limit of the novel probe L2-Zn for Cu²⁺ ion was as low as 2.3×10^-7 mol/L, which is far lower than the guideline value of 1.6×10^-5 mol/L of the United States Environmental Protection Agency.     

Complexation metallique des imides. II. Grandeurs thermodynamiques de formation des complexes de Ag(I), Cd(II), Co(II), Ni(II), Cu(II), Zn(II) avec l''hydantoine

Thermodynamic values for the formation of complexes of Ag⁺, Co²⁺, Ni²⁺, Cu²⁺, Zn²⁺, Cd²⁺ ions with hydantoïn were determined at 25°C in aqueous medium 0.5 M KNO₃. Stability constants were calculated from pH metric measurements while corresponding standard enthalpies were deduced from direct calorimetric determinations. The results are interpreted and compared to those of succinimide complexes previously studied.     

Novel Fluorescent Chemosensors Based on Tryptophan Unit for Cu2+ and Fe3+ in Aqueous Solution

We reported four fluorescent chemosensors containing tryptophan units. The fluorescence spectrum titration experiments suggest that chemosensors 1, 2, 3 and 4 are highly selective for Cu²⁺ and Fe³⁺ over Li⁺, Na⁺, K⁺, Co²⁺, Zn²⁺, Ni²⁺, Hg²⁺ and Cr³⁺ via forming complexes with Cu²⁺ or Fe³⁺, which is confirmed by dramatical quench of fluoreseence in aqueous solution at pH 7.4, thus making all the chemosensors suitable for Cu²⁺ and Fe³⁺ fluorescent sensors.     

Synthesis and fluorescence behaviour of crown and azacrown ethers carrying the dansyl fluorophore as a pendant in acetonitrile solution

The influence of Li⁺, Na⁺, K⁺, Cs⁺, Mg²⁺, Ca²⁺, Sr²⁺, Ba²⁺, Co²⁺, Ni²⁺, Cu²⁺, Zn²⁺, Pb²⁺ and Al³⁺ ions on the spectroscopic properties of the dansyl group covalently linked to crown ether or diazacrown ethers was investigated by means of absorption and emission spectrophotometry. Interaction of the alkali metal ions with all fluoroionophores studied is weak, while alkaline earth metal ions interact strongly causing about 50% quenching of dansyl fluorescence of A21C5-Dns and A₂18C6-Dns. The Cu²⁺, Pb²⁺ and Al³⁺ cations interact very strongly with dansyl chromophore regardless the crown ether type, causing a major change in absorption spectrum of the chromophore and forming non-fluorescent complexes. The Co²⁺, Ni²⁺, Zn², Mg²⁺ and Ag⁺ cations interact moderately with all fluoroionophores studied causing about 20% of fluorescence quenching of dansyl, except for a strong dansyl fluorescence quenching of 15C5-Dns by Co²⁺ ion. The quenching efficiency of didansylated fluoroionophores by the alkali metal ions and alkaline earth metal ions is weaker than monodansylated ones.     

Effect of Zn2+ Ions on Upconversion Emission of Er3+ in Zn/Er:LiNbO3 Crystal

The effect of Zn2+ ions codoped on the upconversion emission of Er3+ ions in Er:LiNbO3 crystal under different excitation wavelength was reported.The upconversion emission spectra of Zn/Er:LiNbO3 follo...     

Preparation and Characterization of Heteropoly Octadecamolybdodiphosphates

Heteropoly molybdophosphates with general formula M(?)P2Mo18O62 ·xH2O, where M = H+, K+, NH4+, Ca2+, Co2+, Ni2+, Cu2+, Zn2+ and Ag+, were prepared and characterlzed by elemental analysis, IR and UV spectrometry and thermal analysis. The solubilities of the compounds were examined. The IR spectra show that the countercations and the crystallization water have an influence upon the vibration frequencies of vMo-Oc and vMo-Oc-Mo·In the UV spectra, the charge-transfer bands are assigned to e→e and e→b2 transition. All the compounds decompose at 328-534℃.     

A Novel Coumarin-based Fluorescence Chemosensor for Fe^3＋

A novel coumarin derivative[7-diethylamino-2-oxo-2H-chromene-3-carboxylic acid（6-amino-pyridin2-yl）-amide,CFe1] has been synthesized and its potential application as a chemosensor for the detection of metal ions has been further investigated.The responses of CFe1 to Fe^3＋ were studied by fluorescence emission spectrometry in the presence of other metal ions such as Al^3＋,Ba^2＋,Ca^2＋,Co^3＋,Cr^3＋,Cu^2＋,Fe^2＋,Hg^2＋,Mg^2＋,Mn^2＋,Na^＋,Ni^＋,Pb^2＋,Zn^2＋,K^＋,and Ag^＋.CFe1 showed a good selectivity for Fe^3＋ with fast response,a wide pH span of 3.3-9.18,and a large Stocks shift.CFe1 in the presence of Fe^3＋ and ethylene diamine tetraacetic acid（EDTA） makes the blue solution fade to colorless,which is due to the formation of CFe1-Fe^3＋ complex instead of any catalytic action of Fe^3＋.Furthermore,the imaging of Fe^3＋ in cultured single mice microglia cells was realized with the aid of CFe1,indicating that CFe1 has a great potential to be used as promising models for the future design of novel and robust chemosensor for metal ion detection in the field of biomedical and environmental analyses.     

Zn(II)-selective membrane electrode based on tetra(2-aminophenyl) porphyrin

A new PVC membrane electrode for Zn²⁺ ions based on tetra(2-aminophenyl) porphyrin (TAPP) as membrane carrier is prepared. The sensor exhibits a linear stable response over a wide concentration range (5.0×10⁻⁵ to 1.0×10⁻¹ M) with a slope of 26.5 mV/decade and a limit of detection 3.0×10⁻⁵ M (1.96 ppm). It has a response time of about l0 s and can be used for at least 8 months without any divergence in potential. The propose membrane sensor revealed good selectivities for Zn²⁺ over a wide variety of other metal ions and can be used in pH range of 3.0–6.0. It was successfully applied to the direct determination of zinc in a pharmaceutical sample and also as an indicator electrode in potentiometric titration of Zn²⁺ ions.     

含蒽双三联吡啶化合物的合成及其对金属离子的荧光识别性能

以蒽,醋酸,溴化氢,1,3,5-三聚甲醛,N,N,N-三甲基-1-十四烷基溴化铵,双(2-吡啶基甲基)胺,三乙胺等为原料,合成了含蒽的双三联吡啶化合物,其结构经¹H NMR、 ¹³C NMR和HR-MS表征。目标产物中含有双三联吡啶结构,可以与金属离子之间具有较强的螯合作用,从而改变原来目标化合物的光学性质,尤其是其荧光性能。实验结果表明：体系中随着Zn²⁺、Ag⁺和Mn²⁺浓度不断增大,含蒽双三联化合物荧光强度不断增强;Cu²⁺、Co²⁺、Hg²⁺、Pb²⁺、Na⁺、Fe³⁺、Ni²⁺均随着浓度的增大,含蒽双三联化合物荧光强度不断减弱。在此基础上,运用荧光光谱法能高灵敏度的检测痕量金属离子。      

Target-triggered inhibiting oxidase-mimicking activity of platinum nanoparticles for ultrasensitive colorimetric detection of silver ion

A facile colorimetric method for sensitive and selective detection of Ag⁺ is successfully developed based on the excellent oxidase-like activity of chitosan-stabilized platinum nanoparticles and the strong metallophilic Pt²⁺-Ag⁺ interactions.     

半导体纳米粒子在反胶束中的合成及其与芘分子间的跨相电子转移

本文在AOT/异辛烷反胶束中合成了CdS和ZnS半导体纳米粒子。粒子的荧光量子产率随胶束水含量的增大而减小。这可以归结为水含量增大导致胶粒表面Cd²⁺或Zn²⁺离子浓度降低,因为这两种离子在胶粒表面富集有利于形成硫空位,从而增大光生电子-空穴对的发光复合。研究发现,Ag⁺离子可以有效猝灭CdS和ZnS纳米粒子的荧光发射,该猝灭过程可以用Ag⁺离子在胶束中的Poisson分布来描述。以溶解在有机相中的pyrene作电子给体,在光激发下可以向CdS粒子注入电子,而和ZnS粒子间没有电荷转移发生,这可以解释为两种半导体的导带边相对于pyrene激发态氧化电位所处的位置不同。Cu²⁺或Ag⁺离子在ZnS颗粒表面吸附,可以形成Cu_xZn_1-xS或Ag_2xZn_1-xS复合粒子,降低ZnS粒子的导带位置,从而使之能够接受来自pyrene激发态的电子。实验结果证实了这种论点。     

Oligomycin A complex structures with some divalent metal cations studied by ESI MS and PM5 semiempirical methods

The ability of Oligomycin A (OLA) to form complexes with monovalent cations was studied by the ESI mass spectrometry and PM5 semiempirical method. At low cone voltage values the ESI MS spectra indicate that OLA formes stable 1:1 complexes with Mg²⁺, Ca²⁺, Sr²⁺, Ba²⁺, Zn²⁺ divalent cations irrespective of the stoichiometry. With increasing cone voltages the formation of the [OLA + M + (ClO₄ or Cl)]⁺ complexes was preferred. This process occurred simultaneously with the formation of fragmentary metal cation complexes with the exception of Pb²⁺ ions which does not form complexes with OLA molecule. PM5 semiempirical calculations allowed the visualizations of all structures of (OLA + M)²⁺ and [OLA + M + (ClO₄or Cl)]⁺ complexes as well as the fragmentary cations.     

基于金属配位键的自修复、可重塑聚丁二烯橡胶的合成及性能

橡胶材料通常因经过硫化及补强等工艺处理而呈现出热固性,因而难以被回收处理,容易造成严重的资源浪费和环境污染.本文通过在聚丁二烯上修饰羧酸基团,再加入锌离子(Zn2+)与羧酸配位,制备了基于金属配位键交联的自修复橡胶(PB-COOH/Zn2+).该橡胶具有良好的机械性能和优秀的自修复及重塑性能,在70℃下修复3 h,其韧性可以恢复到初始强度,修复效率可达100%. PB-COOH/Zn2+较高的聚合物链段运动能力及配位键交联网络良好的动态性不仅赋予其优异的修复性能,还使得其在较温和的条件下可以进行多次重塑,在70℃及5 MPa的条件下重塑3次仍能保持原有的机械性能.此外,通过在PB-COOH/Zn2+中掺杂适量的碳纳米管,不仅增强了其机械性能,还使其具备了电致修复及传感能力,扩宽了PB-COOH/Zn2+作为环境友好型材料的应用前景.     

A Luminescent Metal-Organic Framework with LON Topology for Highly Effective Fluorescence Sensing of Fe3+ and TNP

Aluminescent Ag-based metal-organic framework(1) has been synthesized and its structure has been characterized. Compound 1 was fabricated using the Ag⁺ and bbimb^2‒ ligands and manifestes a rare LON topology. Compound 1 is selective not only in detecting traces of Fe³⁺ and 2,4,6-trinitrophenol(TNP) via luminescence quenching, but also demonstrates high selectivity in the presence of other competitors. Compound 1’s K_sv values towards Fe³⁺ can reach as high as 9.3×10³ L/mol, which is higher than those of several other MOF materials. It is also a recyclable luminous sensor with the potential to be utilized for detecting TNP. Hence, based on its characteristics, compound 1 can be regarded as a prospective luminescence sensor for detecting Fe³⁺ and TNP.