Highly Efficient and Selective Removal of Pb(II) ions by Sulfur-Containing Calcium Phosphate Nanoparticles

A facile one-step co-precipitation method was demonstrated to fabricate amorphous sulfurcontaining calcium phosphate (SCP) nanoparticles, in which the sulfur group was in-situ introduced into calcium phosphate. The resulting SCP exhibited a noticeable enhanced performance for Pb(II) removal in comparison with hydroxyapatite (HAP), being capable of easily reducing 20 ppm of Pb(II) to below the acceptable standard for drinking water within less than 10 min. Remarkably, the saturated removal capacities of Pb(II) on SCP were as high as 1720.57 mg/g calculated by the Langmuir isotherm model, exceeding largely that of the previously reported absorbents. Significantly, SCP displayed highly selective removal ability toward Pb(II) ions in the presence of the competing metal ions (Ni(II), Co(II), Zn(II), and Cd(II)). Further investigations indicated that such ultra-high removal efficiency and preferable affinity of Pb(II) ions on SCP may be reasonably ascribed to the formation of rodlike hydroxypyromorphite crystals on the surface of SCP via dissolution-precipitation and ion exchange reactions, accompanied by the presence of lead sulfide precipitates. High removal efficiency, fast removal kinetics and excellent selectivity toward Pb(II) made the obtained SCP material an ideal candidate for Pb(II) ions decontamination in practical application.     

牛磺酸双核铜络合物为载体的高选择性硫氰酸根离子电极的研究

本文报道了一种以牛磺酸双核铜络合物为中性载体的硫氰酸根PVC膜电极。该电极对硫氰酸根有良好的电位响应并呈现出anti-Hofmeister行为,其选择性顺序SCN^->I^->ClO₄^->Sal^->NO₃^-> NO₂^-> Br^- > Cl^- > SO₃^-> SO₄ ^2-。在20℃ pH 5.0的磷酸缓冲溶液中,其线性范围为1.0´10 ^-1~ 1.0´10^-6mol×L-1,检测线为8.0×10 ^-7mol•L^-1,斜率为 -56.5 mV/pcSCN^-。紫外、红外和交流阻抗研究表明电极的高选择性与载体的立体结构和分析物与中心金属离子的作用相关。将该电极用于废水和人体尿液中硫氰酸根的测定,获得了较满意的结果。     

Indirect Pyrophosphate Determination by Atomic Absorption Using Copper(II) Ions and A Liquid Ion Exchanger

Abstract

Pyrophosphate (5 × 10^?6 M to 5 × 10^?6 M in the final aqueous solution) may be determined in the presence of similar concentrations of phosphate, other condensed phosphates, or some other anions, by measurement of its inhibitory effect on the extraction of copper(II) by Amberlite LA-1 into MIBK or ethyl acetate. The copper extracted is determined by atomic absorption spectrophotometry.     

羧酸铜与单螺旋吡啶胺配体自组装的两种新型超分子配合物

Two novel supramolecular complexes [Cu（bpapa）（dhbd）]·CHaOH （1） and [Cu（bpapa）（ma）]·ma （2） （bpapa= bis[6-（2-pyridylamino）pyrid-2-yl]amine, dhbd=2,3-dihydroxybutanedioate dianion, ma=a-methacrylate） were rationally designed, synthesized and characterized by single crystal X-ray diffraction, IR, electronic spectroscopy and thermogravimetric analyses. Complex 1 was the first oligo-a-pyfidylamino complex based on hydroxypolycarboxylate and self-assembled into a 3D honeycomb configuration network with open channels and tubes containing 1D ladder-shaped double chains formed by hydrogen bonds and aromatic π-π stacking interactions. Complex 2 constructed a 2D supramolecular network extended by 1D chains from dimeric supramolecular synthon through noncovalent supramolecular interactions. In the two complexes, the chelating monohelical ligand adopted all-anti configuration. Density functional theory calculations were applied to 1 and 2.     

Trisannelated Benzene Synthesis by Copper(II) Chloride

Different ketones such as cyclohexanone, cyclopentanone, acetophenone, 2‐acetonaphthalene, 4‐methylcyclohexanone in the presence of an hydrous CuCl₂ (catalytic amounts) at reflux condition for 2–4 hours, without using a solvent led to dimers 2‐(1‐cyclohexane‐1‐yl)‐cyclohexanone 6 , 2‐cyclopentylidene cyclopentanone 10 , trimer dodecahydrotriphenylene (DTP) 4 , trindan (tricyclopentabenzene) 9 , 1,3,5‐ triphenylbenzene (TBP) 12a , 1,3,5‐tri β‐naphthylbenzene 12b and dodecahydro‐2,6,10‐trimethyltriphenylenes 17 and 18 .     

Highly Selective Salicylate Membrane Electrode Based on N,N＇- （Aminoethyl）ethylenediamide Bis（2-salicylideneimine） Binuclear Copper（Ⅱ） Complex as Neutral Carrier

A new ion selective electrode for salicylate based on N,N＇-（aminoethyl）ethylenediamide bis（2-salicylideneimine） binuclear copper（Ⅱ） complex [Cu（Ⅱ）2-AEBS] as an ionophore was developed. The electrode has a linear range from 1.0 × 10^-1 to 5.0 ×10^-7 mol·L^- 1 with a near-Nemstian slope of （ - 55 ±1 ） mV/decade and a detection limit of 2.0 × 10-7 mol·L^-1 in phosphorate buffer solution of pH 5.0 at 25 ℃. It shows good selectivity for Sal^- and displays anti-Hofmeister selectivity sequence： Sal^-〉SCN^-〉 ClO4^- 〉I^-〉 NO2^- 〉Br^-〉 NO3^- 〉Cl^-〉 SO3^2- 〉 SO4^2- The proposed sensor based on binuclear copper（Ⅱ）complex has a fast response time of 5-10 s and can be used for at least 2 months without any major deviation. The response mechanism is discussed in view of the alternating current （AC） impedance technique and the UV-vis spectroscopy technique. The effect of the electrode membrane compositions and the experimental conditions were studied. The electrode has been successfully used for the determination of salicylate ion in drug pharmaceutical preparations.     

A Simple Turn-off Schiff Base Fluorescent Sensor for Copper (II) Ion and Its Application in Water Analysis

An aniline-functionalized naphthalene dialdehyde Schiff base fluorescent probe L with aggregation-induced enhanced emission (AIEE) characteristics was synthesized via a simple one-step condensation reaction and exhibited excellent sensitivity and selectivity towards copper(II) ions in aqueous media with a fluorescence “ turn-off ” phenomenon. The detection limit of the probe is 1.64 × 10⁻⁸ mol·L⁻¹. Furthermore, according to the results of the UV-vis/fluorescence titrations, Job’s plot method and ¹H-NMR titrations, a 1:2 stoichiometry was identified. The binding constant between L and Cu²⁺ was calculated to be K_a = 1.222 × 10³. In addition, the AIEE fluorescent probe L could be applied to detection in real water samples with satisfactory recoveries in the range 99.10–102.90% in lake water and 98.49–102.37% in tap water.     

Copper(II) ion-selective microelectrochemical transistor

A device has been developed for the measurement of copper(II) ions (Cu²⁺) in aqueous medium. The device reported here is an electrochemical transistor which consists of two platinum electrodes separated by 100 μm spacing and bridged with an anodically grown film of polycarbazole. Polycarbazole film (undoped form) is observed to be highly selective for the Cu(II) ions. In a completed device, the conductivity of the polycarbazole film changes on addition of Cu(II) ions. The change in conductivity is attributed to the conformational changes in the polymer phase on occupation of the Cu(II) ions, without affecting electron/proton transfer. The device turns on by adding 2.5 × 10⁻⁶ M Cu(II) ions and reaches a saturation region beyond 10⁻⁴ M Cu(II) ion concentrations. In the above concentration range, the device response [I _D vs. log Cu(II) ion concentration] is linear. The selectivity of the device for other metal ions such as Cu(I), Ni(II), Co(II), Fe(II), Fe(III), Zn(II) and Pb(II) is also studied. Received: 6 April 1999 / Accepted: 20 August 1999     

基于酞菁铜衍生物为载体的电极对水杨酸根的选择性电位响应

本文以2,9,16,23-四硝基酞菁铜(II) (Cu(II)TNPc) 和2,9,16,23-四氨基酞菁铜(II) (Cu(II)TAPc) 为载体制备PVC聚合膜,构建了水杨酸根选择性电极,并探讨了该电极的选择性响应性能。研究了增塑剂的性质、载体的含量及阴、阳离子添加剂对电极电位响应的影响。结果表明,基于Cu(II)TNPc为载体的PVC膜电极对水杨酸根 (Sal－) 呈现出优先选择性电位响应。具有最佳电位响应的电极的膜组成是：(w/w) 3.0% Cu(II)TNPc,67.0% o-NPOE,29.5% PVC和0.5% NaTPB。基于该组成的电极的线性响应范围为1.0×10－1－9.0×10－7 mol·L－1,检测下限为7.2×10－7 mol·L-1,斜率为－59.8±0.5 mV/decade;其响应快速,稳定性好,适宜的pH范围是3.0－7.0。并成功运用于了实际样品中水杨酸含量的测定,获得令人满意的结果。     

Ion Association and Hydration in Aqueous Solutions of Nickel(II) and Cobalt(II) Sulfate

Aqueous solutions of nickel(II) and cobalt(II) sulfate have been investigated at 25 ^∘C by dielectric relaxation spectroscopy (DRS) over a wide range of frequencies (0.2 ≤ ν (GHz) ≤ 89) and salt concentrations (0.025 ≤ c(mol-L⁻¹) ≤ 1.4). The spectra indicate, as for MgSO₄(aq) studied previously, the simultaneous presence of double solvent-separated, solvent-shared and contact ion pairs in both NiSO₄(aq) and CoSO₄(aq). The stepwise formation constants for each ion-pair type and the overall association constant, obtained from the data are in good agreement with ultrasonic relaxation and other estimates. The DR spectra at higher concentrations (c ≥ 0.5 mol-L⁻¹) suggest the existence of a nonlinear triple ion M₂SO₄²⁺(aq). Consistent with the very strong hydration of the salts, which have ‘effective’ hydration numbers approaching 27 at infinite dilution, there are no significant differences in any of the relaxation or thermodynamic parameters for NiSO₄(aq) and CoSO₄(aq), except that the triple ion appears to be somewhat more stable for the latter.     

Reversible Calcium(II)‐Ion Binding through an Apparent pKa Shift of Thermosensitive Block‐Copolymer Micelles

There is an increasing need for smart materials capable of removing multivalent ions from aqueous streams without the inconvenience of brine regeneration as in ion‐exchange processes. Herein, we present a thermoresponsive micellar system consisting of polystyrene–poly(methoxy diethyleneglycol acrylate) block copolymer surfactants modified with carboxylic acid end groups (PS‐PMDEGA‐COOH) that can be used to switch between the adsorption and desorption of divalent calcium(II) cations by a mild temperature trigger, thus providing a new type of thermoregenerable ion‐adsorbing materials. The switch of calcium(II)‐binding capacity is demonstrated to result from a shift in the pK_a value of the carboxylic acid groups by the collapse and redissolution of the PMDEGA block and the associated change in local polarity.     

铜（II）离子对脱镁叶绿素-a荧光猝灭的研究

本文介绍了一种利用荧光熄灭定量的测定铜（II）的新方法。从新鲜菠菜中提取叶绿素-a,用高氯酸溶液处理,制得脱镁叶绿素-a。测量脱镁叶绿素-a的紫外-可见吸收光谱,观测到505和535nm处有特征吸收峰。在60 ℃水浴中,脱镁叶绿素-a的丙酮溶液与铜（II）离子水溶液混合,5分钟后发现混合液颜色变绿,505和535 nm处吸收峰消失。铜（II）离子水溶液与脱镁叶绿素-a的丙酮溶液混合后发生荧光猝灭现象,而类似浓度的其它生理离子在相同反应条件下对脱镁叶绿素-a的荧光猝灭现象不明显。 研究了铜（II）离子与脱镁叶绿素-a的反应时间,反应温度对荧光强度衰减的影响。并通过阿累尼乌斯经验关系估算铜（II）离子与脱镁叶绿素-a反应的活化能约为10 ±1kJ·mol-1。研究了铜（II）离子的浓度对脱镁叶绿素-a的丙酮溶液荧光强度的影响,在8.0×10-5 ～8.0×10-7 mol·dm-3范围内,铜（II）离子的浓度与混合液的荧光强度成线性衰减关系,检测限可达8.0×10-7 mol·dm-3。利用脱镁叶绿素-a的丙酮溶液的荧光强度变化测量,有望发展成为一种检测铜（II）离子的新方法。     

A Novel Coordination Polymer Based on Decavanadate Units Linked by Copper(II) Ethylenediamine Complexes

Summary: A novel coordination polymer[{Cu(en)₂}(V₁₀O₂₈)]_n · 2n[Cu(en)₂(H₂O)] · 2n(H₃BO₃) · 2n(H₂O) was obtained by hydrothermal reaction. The compound crystallizes in the monoclinic crystal system, in the C2/c space group, with a = 26.490 (3) Å; b = 11.6558 (11) Å; c = 19.8426 (19) Å; β = 124.011 (1)°; V = 5078.6(8) ų. The solid structure is formed by polymeric chains, [Cu(en)₂(H₂O)]²⁺ cations, and boric acid and water solvate molecules, stabilized through a multiple hydrogen bond network.     

Kinetic Study of the Reduction of Bromate Ion by Tris(1,10-Phenanthroline)Iron(II) and Aquoiron(II) Ions — Implication for the Bromate-Gallic Acid Oscillating Reaction

The kinetics of the bromate oxidation of tris(1,10-phenanthroline)iron(II) (Fe(phen)₃²⁺) and aquoiron(II) (Fe²⁺ (aq)) have been studied in aqueous sulfuric acid solutions at μ = 1.0M and with Fe(II) complexes in great excess. The rate laws for both reactions generally can be described as -d [Fe(II)]/6dt = d[Br^?]/dt = k[Fe(II)] [BrO^?₃] for [H⁺]₀ = 0.428–1.00M. For [BrO^?₃]₀ = 1.00 × 10^?4M. [Fe²⁺]₀ = (0.724–1.45)x 10^?2 M, and [H⁺]₀ = 1.00M, k = 3.34 ± 0.37 M^?1s^?1 at 25°. For [BrO^?₃]₀ = (1.00–1.50) × 10^?4M, [Fe²⁺]₀ = 7.24 × 10^?3M ([phen]₀ = 0.0353M), and [H⁺]₀ = 1.00M, k = (4.40 ± 0.16) × 10^?2 M^?1s^?1 at 25°. Kinetic results suggest that the BrO^?₃-Fe²⁺ reaction proceeds by an inner-sphere mechanism while the BrO^?₃-Fe(phen)₃²⁺ reaction by a dissociative mechanism. The implication of these results for the bromate-gallic acid and other bromate oscillators is also presented.     

Copper(II) Acetylacetonate: An Efficient Catalyst for Huisgen‐Click Reaction for Synthesis of 1,2,3‐Triazoles in Water

An efficient and green copper(II ) acetylacetonate‐catalyzed protocol for the Huisgen‐click reaction in water at 100 °C has been established. The protocol was not only suitable for the reaction between organic azides and alkynes, but also suitable for one‐pot three‐component reaction among alkyl halides, NaN₃ and alkynes.     

Selective Detection of Mercury（Ⅱ） and Copper（Ⅱ） Based on the Opposite Size-dependent Fluorescence Quenching of CdTe Quantum Dots

Three different size CdTe quantum dots （QDs） capped by 3-mercaptopropionic acid （MPA） have been prepared in aqueous solutions, and their interactions with Cu^2＋ and Hg^2＋ have been investigated. The opposite size-dependent fluorescence quenching of CdTe QDs by Hg^2＋ and Cu^2＋ was observed： Hg^2＋ quenched smaller particles more efficiently than larger ones while larger particles were more markedly quenched by Cu^2＋. Based on the different size responses, Hg^2＋ and Cu^2＋ were respectively detected with high sensitivity and selectivity, for the first time, using the QDs with different sizes but the same components and capping ligands.     

Structure of Perchlorato(2,5,8,11-Tetraazadodecane)Copper (II) Perchlorate Monohydrate

[Cu(C₈H₂₂N₄)]·(ClO₄)₂.H₂O, M_r= 454.80, orthorhombic C222₁, a = 15.481(5), b = 7.404(1), c = 14.827(3)Å, V = 1699.5(8)ų, Z = 4, D_x = 1.78 g/cm³, λ(MoKα) = 0.71073Å, μ = 16.5 cm^?1. F(000) = 940, T = 22°C, R = 6.86%, R_w = 7.66% for 820 observed reflections (I > 2.5σ (I)). The coordination number for the copper(II) ion is five, and the coordination geometry about copper(II) ion is a buckled square pyramid with the tetraamine equatorial and a perchlorate ion axial. The tetraamine is coordinated in a square-plannar manner with slight tetrahedral distortions. The four Cu-N distances span a very narrow range, 1.990(10) ?1.994(14)Å.     

Thermal Investigation of the Compounds of the Copper(II) Mono(o-hydroxybenzoate) with Chelate Ligands

Heteroligand complexes of copper(II) were obtained as a result of the reaction of Cu(II) mono (o-hydroxybenzoate) (monohydrate) with 8-hydroxyquinoline (HOx), o-aminophenol (NH₂Ph) and 2,2′-dipyridyl (2,2′-dipy). The mixture of the mono compound with: Cu(II) di(o-aminobenzoate) or Cu(II) di(o-hydroxybenzaldoximate) were obtained by the reaction with o-aminobenzoic acid (H₂A) and o-hydroxybenzaldoxime (H₂Salox). The obtained compounds and their sinters were subjected to chemical, X-ray and thermal analyses. This revised version was published online in July 2006 with corrections to the Cover Date.     

Thermal Studies of Copper(II) Squarate Complexes of Diamines in the Solid State

CuL₂C₄O₄ [L=ethane-1,2-diamine (en)], CuL₂C₄O₄⋅2H₂O [L=N-methylethane-1,2-diamine (meen), N-ethylethane-1,2-diamine (eten),N-propylethane-1,2-diamine (pren), N-methyl-N’-ethylethane- 1,2-diamine (meeten) andpropane-1,2-diamine (pn)], CuL₂C₄O₄⋅0.5H₂O [L=N,N’-dimethylethane- 1,2-diamine (dmeen)], CuL₂C₄O₄⋅4H₂O [L=propane-1,2-diamine (pn)]and CuL₂C₄O₄⋅H₂O[L=2-methylpropane-1,2-diamine (ibn)] have been synthesized by the addition of respective diamine to finely powdered CuC₄O₄⋅2H₂O and their thermal studies have been carried out in the solid state. Cu(en)₂C₄O₄ upon heating loses one molecule of diamine with shar pcolour change yielding Cu(en)C₄O₄ which upon further heating transforms to unidentified products. All aquated-bis-diamine species [CuL₂C₄O₄⋅2H₂O, CuL₂C₄O₄⋅0.5H₂O and CuL₂C₄O₄⋅H₂O] upon heating undergo deaquation–anation reaction in the solid state showing thermochromism and transform to CuL₂C⁴O₄, which revert on exposure to humid atmosphere (RH ∼90%). All the squarato bis-diamine species, CuL₂C₄O₄, on further heating transform to unidentified products through the formation of CuLC₄O₄ as intermediates. The mono diamine species, have been isolated pyrolytically in the solid state and can be stored in a desiccator as well as in open atmosphere. They are proposed to be polymeric. This revised version was published online in August 2006 with corrections to the Cover Date.     

Synthesis and Characterization of Two New Chiral Copper(II) Compounds Constructed from (+)‐N‐Tosyl‐L‐glutamic Acid

Chiral coordination polymers have attracted intense interest mainly due to their potential applications. Hence, two new chiral copper(II) coordination polymers {[Cu(tsgluO)(H₂O)]₂·3H₂O}_n ( 1 ) and [Cu(tsgluO)(2,2′‐bipy)]_n ( 2 ) (H₂tsglu?(+)‐N‐tosyl‐l‐glutamic acid; 2,2′‐bipy?2,2′‐bipyridine) were synthesized in the absence or presence of 2,2′‐bipy ligand and structurally characterized. A single crystal X‐ray diffraction study revealed that compound 1 consists of a paddle‐wheel dicopper(II) core, which links other equivalents via four tsgluO^2? ligands to form a 1D double chain. Such a chain is further interconnected through weak π‐π stacking and hydrogen bonding interactions to form a 3D H‐bonded supramolecular structure with 1D channels hosting lattice water molecules. Whereas, compound 2 , containing the coordinating 2,2′‐bipy, gives rise to a ladder‐like 1D double chain. Antiferromagnetic interactions were observed in 1 and 2 .