共查询到20条相似文献,搜索用时 31 毫秒
1.
Navneet Kaur Jasvinder Singh Gargi Dhaka Richa Rani Vijay Luxami 《Supramolecular chemistry》2013,25(7-8):453-459
2-Hydroxy-1-naphthaldehyde-based benzothiazole chemosensor (1) undergoes absorption and fluorescence changes with addition of CN? and Cu2+ ions. Addition of CN? ions results in the appearance of two new bands at 420 and 440 nm. However, Cu2+ addition causes decrease in absorption band at 370 nm up to 12 equiv., while addition of higher equiv. of Cu2+(~190 equiv.) results in the appearance of two new bands at 400 and 800 nm. Differential absorption changes observed with addition of Cu2+ and CN? ions results in the construction of ‘NOR’ and ‘INHIBIT’ logic gates at 370 and 440 nm, respectively. 相似文献
2.
Ab initio cluster quantum chemical calculations at the Hartree–Fock (HF/Lanl2dz) and correlated second-order Moller–Plesset perturbation theory (MP2/Lanl2dz) levels were performed for NO and N2O interactions with Ag+ and Cu+ ion-exchanged zeolites. The interaction energies were estimated in a conventional way and also corrected for basis set superposition errors. It was shown that the highly dispersed Ag+ counterions establish twofold coordination to the lattice oxygens on the zeolite surface, similar to the case of Cu+ ions. However, both NO and N2O bind relatively strongly to the Cu active sites of Cu+ ion-exchanged zeolites than those of the Ag+ site of the Ag+ ion-exchanged zeolites. Based on the results of these calculations, the two different forms of adsorption for these molecules on the catalyst surface, the nature of their binding and characteristics of the adsorption properties have been discussed. Finally, some comparisons with the results obtained by a variety of density functional theory calculations on target systems have been presented. 相似文献
3.
In this work, we synthesised and characterised three novel fluorescence macrocyclic sensors containing optically active dansyl groups. The studies for the interaction of the synthesised compounds with various mental ions (Li+, Na+, K+, Ag+, Mg2+, Ca2+, Ba2+, Pb2+, Zn2+, Co2+, Cd2+, Hg2+, Ni2+, Cu2+, Mn2+, Cr3+, Al3+, Fe3+) were performed by fluorescence titration, Job’s plot, ESI-MS and DFT calculations. The results showed that the sensors 1a–1c displayed selective recognition for Cu2+ and Fe3+ ions and formed stoichiometry 1:1 complex through PET mechanism in DMSO/H2O solution (1:1, v/v, pH 7.4 of HEPES). The binding constant (K) and detection limit were calculated. 相似文献
4.
A simple epoxy-based oligomer 1 containing naphthylazobenzene-appended dithia-aza moieties was prepared. In UV–vis measurements, the proposed oligomer showed the ion-sensing ability to Hg2+ and Cu2+ ions. The discrimination between two differently responding Hg2+ and Cu2+ ions was also realised from ‘ON–OFF’ type fluorescence responses of 1. 相似文献
5.
Sukhdeep Kaur 《Tetrahedron letters》2004,45(26):5081-5085
Fluorescent chemosensor 3 can sense Cu2+ ions (1-8 μM) even in the presence of elevated levels of Ni2+, Cd2+, Zn2+, Hg2+, Ag+ and Pb2+ (5000 μM). 3 can also analyze for Ag+ ions (50-500 μM) in the presence of Ni2+, Cd2+, Zn2+, Hg2+ and Pb2+ (5000 μM) but Cu2+ strongly interferes. 相似文献
6.
Qiuping Hu Yuling Liu Zhengqiang Li Rongzheng Wen Yuan Gao Yiling Bei Qingzeng Zhu 《Tetrahedron letters》2014
A new rhodamine B derivative bearing a hydrazone group has been designed and prepared. The synthesized colorimetric and fluorescent molecular chemosensor can be used as a dual probe, selectively detecting Al3+ and Cu2+ in acetonitrile solution by monitoring changes in the absorption and fluorescence spectral patterns. The results show that Al3+ ions can induce a greater fluorescence enhancement, while the addition of Cu2+ ions induces a strong UV–vis absorption enhancement with weak fluorescence. The limits of detection of Cu2+ and Al3+ were estimated to be 2.9 × 10−7 M and 8.3 × 10−9 M, respectively. 相似文献
7.
A series of sulfonamido-substituted phenylethylidene-3,4-dihydro-1H-quinoxalin-2-one derivatives in which both of the fluorophore and ionophore are integrated into one structural unit, have been investigated. They all exhibit high selectivity toward Cu2+ in ethanol in the presence of other metallic ions (Zn2+, Mg2+, Co2+, Ni2+, Mn2+, Ca2+, and Ag+), as well as fast, stable, and reversible binding, as is evidenced by the observation of a red shift in the UV-vis spectrum, ‘ON-OFF’ fluorescence response. In addition, titration and MALDI-TOF measurements indicated that a 1:1 (and possibly also 2:1 (organic ligand: Cu2+) complexes were formed, depending on the relative amount of Cu2+ added to the solution of the organic ligand. It was also found that the binding constant could be tuned by modifying the nature and position of the substituents attached to the central benzene ring in the quinoxalone derivative. In acetonitrile, unlike in ethanol, these ligands undergo oxidation-decomposition by Cu2+ and therefore, no UV-vVis absorption bands could be observed. However, due to color change (from yellow to transparent) they could be useful as dosimeters in this solvent. 相似文献
8.
Azeem Ullah Muhammad Ateeq Muhammad Raza Shah Munira Taj Muhammad Imran Khan 《International journal of environmental analytical chemistry》2018,98(10):977-985
In this work, we have successfully developed novel silver nanoconjugates of pyrazolone analogue and screened its chemosensing potential in aqueous medium. Bispyrazolone silver nanoparticles (Bispyra-AgNPs) were synthesised and characterised through FTIR, UV-visible spectroscopy and atomic force microscopy. The sensing ability was explored towards Ca2+, Cd2+, Co2+, Cu2+, Fe2+, Li+, Pb2+, La3+, Hg2+, Mg2+, Ni2+ and Ba2+ metal ions, respectively. Bispyra-AgNPs showed a highly quenching potential in selective recognition of Cu2+and colour of the solution immediately turned from yellow to purple, after the addition of Cu2+ in to the solution. The developed method also displayed a remarkable selectivity for Cu2+ over others interfering metal ions. The binding ratio and stoichiometry of host-guest complex was found to be 1:1 and determined by Job’s method. The propose method is facile and sensitive to detect Cu2+ with detection limit of 10 µM. 相似文献
9.
Based on a boron dipyrromethene (BODIPY) derivative containing an N, O and S tridentate ligand, a Cu2+ fluorescent probe BTCu was developed. The detection mechanism was verified as Cu2+-promoted oxidative dehydrogenation of an amine moiety, leading to a formation of a fluorescent Cu+-Schiff base complex. Free BTCu exhibited a maximum absorption wavelength at 496 nm, and a very weak maximum emission at 511 nm. Upon addition of various metals ions, it showed large fluorescence enhancement toward Cu2+ (417-fold in MeCN and 103-fold in MeCN/HEPES solution, respectively) with high selectivity. The detection limits are as low as 1.74 × 10−8 M and 4.96 × 10−8 M in the two different solutions, respectively. And BTCu could work in a wide pH range with an extraordinary low pKa of 1.21 ± 0.06. Using fluorescence microscopy, the probe was shown to be capable of penetrating into living cells and imaging intracellular Cu2+ changes. 相似文献
10.
Mahendra Sonawane Kundan Tayade Suban K. Sahoo Chatur P. Sawant 《Journal of Coordination Chemistry》2016,69(18):2785-2792
A new lawsone-based azo-dye 2-hydroxy-3-((pyridin-2-ylmethyl)diazenyl)naphthalene-1,4-dione (1) was synthesized and applied for sensing of metal ions. Receptor 1 showed selective fluorescent and colorimetric response for the detection of Cu2+ and Fe3+ over other tested metal ions. The fluorescence intensity of 1 was significantly quenched allowing detection of Fe3+ and Cu2+ down to 0.61 and 6.06 μM, respectively. The binding has been established by fluorescence spectroscopic method. Receptor 1 provided a 1?:?1 binding scaffold for recognition of Fe3+ and Cu2+ ions with the association constant of 3.33 × 106 and 3.33 × 105 M?1, respectively. The B3LYP/6-31G/LANL2DZ method was employed for the optimization of 1 and 1·Fe3+ and 1·Cu2+. 相似文献
11.
合成了2,4-二(2-噻吩乙烯基)-6-(4'-N,N-二甲氨基苯乙烯基)-1,3,5-均三嗪(2)并鉴定了其结构。在乙腈-水混合介质中,化合物2在355和416nm处呈现双吸收峰,加入Cu2+,Hg2+ 和Fe3+ 后,均在520nm附近形成新的吸收峰。化合物2与Cu2+、Hg2+ 和Fe3+ 均形成1:1型配合物,其结合常数分别为1.9×105L·mol-1,6.6×103L·mol-1,2.7×103L·mol-1。对照化合物4与金属离子的光谱响应与化合物2相似,仅吸收峰的位置不同。因此,可认为化合物2和4中三嗪环中的N和噻吩环中的S与Cu2+、Hg2+ 和Fe3+ 共同配位形成了稳定的金属配合物。 相似文献
12.
An ion-selective bulk optode (ISBO) for sensing Cu2+ and Pb2+ ions based on plasticized poly(vinyl chloride) containing 1,10-dibenzyl-1,10-diaza-18-crown-6 (DBzDA18C6) as ionophore and 1-(2-pyridylazo)-2-naphthol (PAN) as chromoionophore was prepared. The effects of DBzDA18C6/PAN and NaTPB/PAN mole ratios on the response behavior of the ISBO were investigated. The ISBO membrane shows enhanced selectivities for Cu2+ (at 530 nm) and Pb2+ (at 467 nm) over alkali, alkaline earth and other transition metal ions. The optical selectivity coefficients were measured using the separate solution method (SSM) in the two corresponding wavelengths at pH=5. The detection limit for Cu2+ and Pb2+ are 3.2×10−7 and 1.0×10−8 M, respectively. 相似文献
13.
Umesh A. Fegade Suban K. Sahoo Amanpreet Singh Narinder Singh Sanjay B. Attarde Anil S. Kuwar 《Analytica chimica acta》2015
A fluorescent based receptor (4Z)-4-(4-diethylamino)-2-hydroxybenzylidene amino)-1,2dihydro-1,5-dimethyl-2-phenylpyrazol-3-one (receptor 3) was developed for the highly selective and sensitive detection of Cu2+ and Zn2+ in semi-aqueous system. The fluorescence of receptor 3 was enhanced and quenched, respectively, with the addition of Zn2+ and Cu2+ ions over other surveyed cations. The receptor formed host-guest complexes in 1:1 stoichiometry with the detection limit of 5 nM and 15 nM for Cu2+ and Zn2+ ions, respectively. Further, we have effectively utilized the two metal ions (Cu2+ and Zn2+) as chemical inputs for the manufacture of INHIBIT type logic gate at molecular level using the fluorescence responses of receptor 3 at 450 nm. 相似文献
14.
L. Hajiaghababaei A. Badiei M. Shojaan M.R. Ganjali G.M. Ziarani P. Zarabadi-Poor 《International journal of environmental analytical chemistry》2013,93(12):1352-1364
A rapid method for the extraction and monitoring of nanogram level of Pb2+, Cu2+ and Zn2+ ions using uniform silanized mesopor (SBA-15) functionalized with diethylenetriamine groups and flame atomic absorption spectrometry (FAAS) is presented. The preconcentration factor of the method is 100 and detection limit of the technique is 5.5?ng?mL?1 and 1.4?ng?mL?1 and 0.1?ng?mL?1 for Pb2+, Cu2+ and Zn2+ respectively. The time and the optimum amount of the sorbent, pH and minimum amount of acid for stripping of ions from functionalized SBA-15 were tested. The maximum capacity the functionalized SBA-15 was found to be 183.0 (±1.9) µg, 156.0 (±1.5) µg and 80.0 (±1.6) µg of Pb2+, Cu2+ and Zn2+/mg functionalized SBA-15, respectively. 相似文献
15.
Three novel compounds bearing 2,7-dihydroxylnaphthalene capable of detecting Cu2+ or Fe3+ have been synthesised based on photoinduced electron transfer. The ability of these compounds for complex transition metal ions has been studied, and complex stoichiometry for Cu2+ and Fe3+ complex has been determined in the Tris–HCl (0.01 M DMSO/H2O (v/v) 1:1, buffer, pH 7.4) solution system by fluorescence titration experiments. These chemosensors form a 1:1 complex with Cu2+ or Fe3+ and show a fluorescent quenching with a binding constant of (4.46 ± 0.29) × 103 and (8.04 ± 0.26) × 104, respectively. 相似文献
16.
Esat Bozkurt Bünyamin Karabulut 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2009,73(5):871-874
The electron paramagnetic resonance spectra of Cu2+ doped diaquabis(nicotinamide)bis(o-sulfobenzimidato-N)-cadmium(II) (hereafter, CdNAS) single crystals which were taken at room temperature are discussed. It was found from the analysis of the EPR data that the Cu2+ ions substitute for magnetically inequivalent Cd2+ ions. Two magnetically inequivalent Cu2+sites were observed. The principal values of the g and the hyperfine tensors were determined. The ground state wave functions of the unpaired electron of Cu2+ ions in two sites were constructed and type of the distortion was determined. 相似文献
17.
Preparation and characterization of nylon 6/Cu2+-exchanged and Fe3+-exchanged montmorillonite nanocomposite 总被引:1,自引:0,他引:1
Jie Liu Yuan Hu Shaofeng Wang Lei Song Zuyao Chen Weicheng Fan 《Colloid and polymer science》2004,282(3):291-294
Nylon 6/Cu2+-exchanged and Fe3+-exchanged montmorillonite nanocomposites have been prepared by a melt intercalation technique directly from Cu2+-exchanged and Fe3+-exchanged montmorillonite. Hexadecyltrimethylammonium bromide was chosen as the clay/matrix reactive compatibilizer. The intercalation spacing and the degree of dispersion were determined by X-ray diffraction and transmission electron microscopy. Also the thermal character of the nanocomposites prepared was analyzed by thermogravimetric analysis. 相似文献
18.
G. Anbalagan G. Sankari S. Ponnusamy R. Thilak kumar S. Gunasekaran 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2009,74(2):404-409
Sanidine, a variety of feldspar minerals has been investigated through optical absorption, vibrational (IR and Raman), EPR and NMR spectroscopic techniques. The principal reflections occurring at the d-spacings, 3.2892, 3.2431, 2.9022 and 2.6041 Å confirm the presence of sanidine structure in the mineral. Sanidine shows five prominent characteristic infrared absorption bands in the region 1200–950, 770–720, 590–540 and 650–640 cm−1. The Raman spectrum shows the strongest band at 512 cm−1 characteristic of the feldspar structure, which contains four membered rings of tetrahedra. The UV–vis–NIR absorption spectrum had strong absorption features at 6757, 5780 and 5181 cm−1 due to the combination of fundamental OH– stretching. The bands at 11236 and 8196 cm−1and the strong, well-defined band at (30303 cm−1 attest the presence of Fe2+ and Fe3+, respectively, in the sample. The signals at g = 4.3 and 3.7 are interpreted in terms of Fe3+ at two distinct tetrahedral positions Tl and T2 of the monoclinic crystal structure The 29Si NMR spectrum shows two peaks at −97 and −101 ppm corresponding to T2 and T1, respectively, and one peak in 27Al NMR for Al(IV). 相似文献
19.
Ioannis T. Papadas Chariklia Kosma Yiannis Deligiannakis 《Journal of colloid and interface science》2009,339(1):19-30
Cu2+ binding on γ-Al2O3 is modulated by common electrolyte ions such as Mg2+, , and in a complex manner: (a) At high concentrations of electrolyte ions, Cu2+ uptake by γ-Al2O3 is inhibited. This is partially due to bulk ionic strength effects and, mostly, due to direct competition between Mg2+ and Cu2+ ions for the SO− surface sites of γ-Al2O3. (b) At low concentrations of electrolyte ions, Cu2+ uptake by γ-Al2O3 can be enhanced. This is due to synergistic coadsorption of Cu2+ and electrolyte anions, and . This results in the formation of ternary surface species (SOH2SO4Cu)+, (SOH2PO4Cu), and (SOH2HPO4Cu)+ which enhance Cu2+ uptake at pH < 6. The effect of phosphate ions may be particularly strong resulting in a 100% Cu uptake by the oxide surface. (c) EPR spectroscopy shows that at pH pHPZC, Cu2+ coordinates to one SO− group. Phosphate anions form stronger, binary or ternary, surface species than sulfate anions. At pH pHPZC Cu2+ may coordinate to two SO− groups. At pH pHPZC electrolyte ions and are bridging one O-atom from the γ-Al2O3 surface and one Cu2+ ion forming ternary [γ-Al2O3/elecrolyte/Cu2+] species. 相似文献
20.
Azo 8-hydroxyquinoline benzoate (2) was synthesized and studied to detect metal ions. Distinct color change was found for compound 2 in the presence of transition metal ions Hg2+ or Cu2+ in CH3CN, respectively, which makes it possible for distinguishing Hg2+ and Cu2+ from other metal ions by the ‘naked eye’. 相似文献