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1.
2.
通过“click”反应合成了两个新的由三氮唑连接的含芘的杯[4]芳烃。 化合物1含有两个芘单元,对Zn2+表现出比率荧光响应,且对Cu2+, Hg2+ 和 Pb2+表现出选择性的荧光淬灭;而化合物2只含一个芘单元,对铜离子有显著的荧光淬灭,对汞离子有中等程度的荧光淬灭。利用化合物1对锌离子和铜离子不同的荧光响应,设计了INH和NOR逻辑门。  相似文献   

3.
《Electroanalysis》2006,18(10):1019-1027
A new PVC membrane potentiometric sensor for Ag(I) ion based on a recently synthesized calix[4]arene compound of 5,11,17,23‐tetra‐tert‐butyl‐25,27‐dihydroxy‐calix[4]arene‐thiacrown‐4 is developed. The electrode exhibits a Nernstian response for Ag(I) ions over a wide concentration range (1.0×10?2?1.0×10?6 M) with a slope of 53.8±1.6 mV per decade. It has a relatively fast response time (5–10 s) and can be used for at least 2 months without any considerable divergence in potentials. The proposed electrode shows high selectivity towards Ag+ ions over Pb2+, Cd2+, Co2+, Zn2+, Cu2+, Ni2+, Sr2+, Mg2+, Ca2+, Li+, K+, Na+, NH4+ ions and can be used in a pH range of 2–6. Only interference of Hg2+ is found. It is successfully used as an indicator electrode in potentiometric titration of a mixture of chloride, bromide and iodide ions.  相似文献   

4.
The competitive removal of Pb2+, Cu2+, and Cd2+ ions from aqueous solutions by the copolymer of 2‐acrylamido‐2‐methyl‐1‐propane sulfonic acid (AMPS) and itaconic acid (IA), P(AMPS‐co‐IA), was investigated. Homopolymer of AMPS (PAMPS) was also used to remove these ions from their aqueous solution. In the preparation of AMPS–IA copolymer, the molar percentages of AMPS and IA were 80 and 20, respectively. In order to observe the changes in the structures of polymers due to metal adsorption, FTIR spectra by attenuated total reflectancetechnique and scanning electron microscopy (SEM) pictures of the polymers were taken both before and after adsorption experiments. Total metal ion removal capacities of PAMPS and P(AMPS‐co‐IA) were 1.685 and 1.722 mmol Me2+/gpolymer, respectively. Experimental data were evaluated to determine the kinetic characteristics of the adsorption process. Competitive adsorption of Pb2+, Cu2+, and Cd2+ ions onto both PAMPS and P(AMPS‐co‐IA) was found to fit pseudo‐second‐order type kinetics. In addition, the removal orders in the competitive adsorption of these metal ions onto PAMPS and P(AMPS‐co‐IA) were found to be Cd2+ > Pb2+ > Cu2+ and Pb2+ > Cd2+ > Cu2+, respectively. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   

5.
A new chemosensor for Cu2+ was synthesized based on 1,2,3,4,5,6,7,8,9,10‐decahydroacridine‐1,8‐dione dyes, which exhibited an obvious fluorescent selectivity to the sensing of Cu2+ ions over other cations, such as Na+, K+, Ca2+, Cd2+, Co2+, Hg2+, Mg2+, Mn2+, Ni2+, Zn2+, Ag+ and Pb2+. Moreover, it presented a fluorescent switch function when EDTA was added to the compound‐Cu2+ complex in examined systems.  相似文献   

6.
Rigid N‐(substituted)‐2‐aza‐[3]‐ferrocenophanes L1 and L2 were easily synthesized from 1,1 ‐dicarboxyaldehydeferrocene and the corresponding amines. Ligands L1 and L2 were characterized by 1H NMR, 13C NMR and single‐crystal X‐ray crystallography. The coordination abilities of L1 and L2 with metal ions such as Cu2+, Mg2+, Ni2+, Zn2+, Pb2+ and Cd2+ were evaluated by cyclic voltammetry. The electrochemical shift (ΔE1/2) of 125 mV was observed in the presence of Cu2+ ion, while no significant shift of the Fc/Fc + couple was observed when Mg2+, Ni2+, Zn2+, Pb2+, Cd2+ metal ions were added to the solution of L1 in the mixture of MeOH and H2O. Moreover, the extent of the anodic shift of redox potentials was approximately equal to that induced by Cu2+ alone when a mixture of Cu2+, Mg2+, Ni2+, Zn2+, Pb2+ and Cd2+ was added to a solution of L1. Ligand L1 was proved to selectively sense Cu2+ in the presence of large, excessive first‐row transition and late‐transition metal cations. The coordination model was proposed from the results of controlled experiments and quantum calculations. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   

7.
Hui Xu  Xiwen Zeng  Huiling Dai 《中国化学》2011,29(10):2165-2168
A new fluorescent chemosensor based upon 1,8‐naphthalimide and 8‐hydroxyquinoline was synthesized, and its fluorescent properties in the presence of different metal cations (Hg2+, Ag+, Zn2+, Fe2+, Cd2+, Pb2+, Ca2+, Cu2+, Mg2+, and Ba2+) were investigated. It displayed fluorescence quenching with some heavy and transition metal (HTM) ions, and the quenching strongly depended on the nature of HTM ions.  相似文献   

8.
A conjugated polymer was synthesized by the polymerization of 4,7‐dibromobenzo[2,1,3]thiadiazole ( M‐1 ) with tri{1,4‐diethynyl‐2,5‐bis(2‐(2‐methoxyethoxy)‐ethoxy)}‐benzene ( M‐2 ) via Pd‐catalyzed Sonogashira reaction. The polymer shows strong orange fluorescence. The responsive optical properties of the polymer on various metal ions were investigated through photoluminescence and UV–vis absorption measurements. The polymer displays highly sensitive and selective on‐off Hg2+ fluorescence quenching property in tetrahydrofuran solution in comparison with the other cations including Mg2+, Zn2+, Co2+, Ni2+, Cu2+, Ag+, Cd2+, and Pb2+. More importantly, the fluorescent color of the polymer sensor disappears after addition of Hg2+, which could be easily detected by naked eyes. The results indicate that this kind of polymer sensor incorporating benzo[2,1,3]thiadiazole moiety as a ligand can be used as a novel colorimetric and fluorometric sensor for Hg2+ detection. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011  相似文献   

9.
A series of new calix[4]resorcinarenes (rccc-isomer) and resorcinols functionalized by acetylhydrazone binding fragments have been synthesized. The IR and NMR data and stereochemical behaviour of hydrazones are reported and compared with the results of earlier investigations. The barriers of rotation of hydrazone fragments for some octahydrazone derivatives of calix[4]resorcinarenes and their resorcinol analogues have been determined by NMR-measurements. The complexing behaviour of bis- and octahydrazones has been studied by liquid-liquid extraction towards the s-metal ions (Li+, Na+, K+, Cs+ and Ca2+), p-metal ions (Pb2+), d-metal ions (Co2+, Ni2+, Cu2+, Zn2+, Cd2+ and Hg2+) and f-metal ions (La3+, Gd3+ and Lu3+). The stoichiometry of complexes and the extraction constants have been determined. It has been established that octahydrazones do not extract alkali metal cations but show excellent selectivity towards transition and soft heavy metal cations (especially Hg2+ or Pb2+).  相似文献   

10.
A series of new calix[4]arene(amido)mono-crown compounds have been synthesized through aminolysis of calix[4]arene esters and intramolecular cyclization of the intermediates. The title compounds were converted into their nitro and azo substituted derivatives to provide novel photoresponsive molecular receptors for transition metal ions. Single crystal X-ray analysis of calix[4]arene(ethyleneamido)mono-crown (2a) revealed that the compound is present in a cone conformation with an amido loop that caps the lower rim of calix[4]arene cavity to result in stacking along axis a and axis c to provide supramolecular aggregates in the solid state. Evaluation of synthesized macrocycles in the solution phase for recognition of transition metal cations (Cr3+, Fe2+, Co2+, Ni2+, Cu2+, Ag+, Cd2+, Pb2+, Hg+, Hg2+, Pd2+, and Pt2+) by UV-visible spectroscopy revealed that p-tert-butyl-calix[4]arene mono-(amidocrown) 1c selectively shows a blue shift at 38 nm on interaction with Hg+ ions.  相似文献   

11.
A new oligomeric calix[4]arene‐thiacrown‐4 ( 5 ) was synthesized via a condensation reaction of 5,11,17,23‐tetra‐tert‐butyl‐25,27‐bis‐(4‐aminobenzyloxy)‐calix[4]arene‐thiacrown‐4 ( 4 ) with adipoyl dichloride. In this oligomerization reaction only five/six calix[4]arene‐thiacrown‐4 units were linked in the oligomeric chain. The complexation studies of 5 were made with liquid–liquid‐ extraction and solid–liquid‐sorption procedures. For comparison, the extraction efficiencies of monomers 1 , 3 , and 4 to selected transition metals are reported. The selectivity of monomers 3 and 4 toward Cu2+, Hg2+, and Pb2+ was lost after oligomerization in the two‐phase extraction systems. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 186–193, 2004  相似文献   

12.
《Electroanalysis》2005,17(11):1015-1018
A new pendant‐arm derivative of diaza‐18‐crown‐6, containing two oxime donor groups, has been synthesized and incorporated into a polyvinyl chloride (PVC) membrane ion‐selective electrode. The electrode shows selectivity for Ag+ ion, with a near Nernstian response. Pb2+, Cu2+, Hg2+, and Tl+ are major interfering ions, with Cd2+ having minor interference. The electrode shows no potentiometric response for the ions Mg2+, Al3+, K+, Ca2+, Ni2+, Fe3+, and La3+, and is responsive to H+ at pH<6.  相似文献   

13.
A chloroform membrane system containing dibenzodiaza‐15‐crown‐4 was found to be a highly efficient and selective transport of Ag+ ions through a chloroform liquid membrane. In the presence of thiosulfate ion as a suitable ion stripping agent in the receiving phase, the amount of silver transported across the liquid membrane after 105 minis 95 ± 1.3%. The selectivity of Ag+transport from aqueous solutions containing Tl+, Pb2+, Cd2+, Ni2+, Co2+, K+, Ca2+, Sr2+, Hg2+, Zn2+, Cu2+was investigated. The interfering effect of Cu2+ ions was drastically diminished in the presence of EDTA as a proper masking agent in the source phase.  相似文献   

14.
The iiii stereoisomer of the tetrathiophosphonate-calix[4]resorcinarene host 1 exhibited excellent extraction properties towards soft metal ions, with a better affinity for Ag+ (91%), than for Tl+ (38%) and Hg2+ (16%). The extraction of other picrate salts (Cu2+, Ni2+, Co2+, Zn2+, Cd2+, Pb2+) was not detected. The stoichiometry and the structure of the Hg2+, Tl+ and Ag+ complexes were studied by NMR in solution and gave respectively 1:1, 1:1 and 1:2 host-guest complexes. The formation of the self-assembled 12·(AgPic)4 complex was independent on the anion and only observed with silver(I) ion.  相似文献   

15.
Complex formation between N,N,N′,N′‐tetrakis(2‐aminoethyl)ethane‐1,2‐diamine (penten) and the metal ions Mn2+, Co2+, Cu2+, Zn2+, Cd2+, Hg2+, Ag+, Pb2+, and Tl3+ (in 1.00M NaNO3 and 25°) was investigated by potentiometry and spectrophotometry. These are the first reported values of the stability constants for this ligand with Ag+, Pb2+, and Tl3+. The X‐ray crystal structure of [Tl(NO3)(penten)](NO3)2 was determined. In this structure, Tl3+ shows a coordination number of seven made up of the six N‐donors and one O‐atom of NO.  相似文献   

16.
Jing Wang 《Talanta》2009,78(2):477-5212
Silica gel-immobilized, di-ionizable calix[4]arenes are employed as stationary phases in ion-exchange chromatography for selected heavy metal ions. Sorption efficiencies for Pb2+ are dependent on the structure of the calix[4]arene ligand and the linker that joins the ligand to the silica gel, as well as the acidity of the sample solution. Although the resins exhibit only poor sorption of Cd2+, they are found to be scavengers for Hg2+. Competitive sorption studies are conducted with selected resins.  相似文献   

17.
Two novel 25,27-dihydroxy-26,28-bis(3-phenylthiapropxy)-calix[4]arene(3) and 25,27-dihydroxy-26,28-bis(3-phenylthiapropoxy)-5,11,17,23-tetra-tert-butylcalix[4] arene (4) were synthesized for the evaluation of their ion-selectivity in ion-selective electrodes(ISEs).ISEs based on 3 and 4 as neutral ionophores were prepared,and their selectivity coefficients for Ag^ (lg KAg,M^pot)were investigated against other alkali metal,alkaline-earth metal,aluminum,thallium(Ⅰ),Lead and some transition metal ions using the separate solution method (SSM).These ISEs showed excellent Ag^ seletivity over most of the interfering cations examined,except for Hg^2 and Fe^2 having relative smaller interference(lg KAg,M^pot≤-2.1).  相似文献   

18.
The new application of C-dec-9-enylcalix[4]resorcinarene (R1), as an ionophore to detect heavy metals (HMs) cations (Cd2+, Hg2+, Cu2+, and Pb2+) in the aqueous media has been investigated through the preparation of an effective mass-sensitive sensor via the exploitation of a flow-type QCM-I technique. By adjusting the ions’ amounts in model solutions over a wide range of concentrations, acquired changes in the oscillating frequency related to the loading of metal ions on the sensor’s surface were gained, and thus favorable metrological parameters displaying the lowest detection limit (LOD) associated with copper ions (10 ppb). Simultaneously, a novel voltammetric sensor was prepared by modifying gold screen-printed electrodes (SPEs) with R1. Electrochemical characterization employing CV, SWV, and EIS was carried out, showing the success of the electrode modification. Then, the experimental conditions of supporting electrolyte, pH, accumulation time, and accumulation potential were optimized to achieve an enhanced detection. The R1@SPE sensor simultaneously detected the HMs (Cd2+, Hg2+, Cu2+, Pb2+), and the lowest LOD was associated with Pb2+ (0.19 ppb). The selectivity evaluation of the electrochemical sensor was performed by studying the effect of interferences majorly present in water sources (Mg2+, Ni2+, Zn2+, Al3+, and K+) on the SWV detection signals, and it was revealed that the interfering ions did not affect the simultaneous detection of the studied HMs (RSD less than 5%), the voltammetric sensors also presented excellent repeatability and reproducibility (RSD less than 5%).  相似文献   

19.
Abstract

A new inorganic ion exchanger, lead antimonate has been synthesized having an Pb:Sb ratio of 1:5 and cation exchange capacity of 1.46 mequiv./g. It is fairly stable in water and dilute solutions of acids, bases and salts. Ion distribution studies on twenty metal ions have been determined on this gel at pH 1,2,3 and 5. The following mixtures have been separated: Mg2+ - Pb2+, Zn2+ - Pb2+, Zn2+ - Pb2+, Cu2+ - Pb2+, Al3+ - Pb2+, Zn2+ - Cd2+ and Mg2+ - Cd2+. Mg2+ and Al3+ were removed with 0.4 M ammonium nitrate, Cu2+ and Zn2+ with 0.4 M ammonium nitrate + 0.1M nitric acid (1:1), Pb2+ with 0.5M nitric acid and Cd2+ with 0.25M nitric acid. A tentative structure of this material is proposed on the basis of chemical analysis, pH titrations, thermogravimetry and IR spectrophotometry.  相似文献   

20.
李广科a  b  刘敏a  b  杨国强a  陈传峰  a  黄志镗  a 《中国化学》2008,26(8):1440-1446
我们方便地合成了上沿修饰四丹磺酰胺基团的杯[4]芳烃衍生物1,发现该化合物在含50%水的乙腈中显示出对汞离子高选择性和灵敏性的识别作用,竞争实验表明多数金属离子对其检测干扰较小。机理研究结果表明荧光萃灭源于由丹磺酰胺基团到汞离子的光致电子转移过程。另外,通过研究1和1-Hg2+的荧光衰减实验,以及对比双丹磺酰胺杯[4]芳烃2和单丹磺酰胺杯[4]芳烃3对汞离子的识别作用,发现化合物1的四丹磺酰胺基团具有很好的预组织和协同作用。化合物1对汞离子的检测限为3.41×10-6 mol·L-1,这可以使1成为一个潜在的汞离子荧光化学传感器。  相似文献   

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