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1.
《Ceramics International》2015,41(4):5537-5546
A new kind of composite mica pigments were prepared by coating Co2−xMxTiO4 composite oxide nanoparticles onto mica, to investigate the effects of doping ions Mg2+, Mn2+, Ni2+, Cu2+ and Zn2+ on the properties of the doped composite pearlescent pigments, such as the crystal structure, color and shading power. The structure, morphology, color and shading power of the coated pigments were characterized by the X-ray diffraction (XRD), scanning electron microscopy (SEM), UV–vis spectrophotometer and CIE L*a*b* methods. SEM images of coated pigments showed that mica were coated uniformly with a single layer of dispersed nanoparticles. Research of the doped composite pigments showed that the doping ions had entered into the spinel crystal structure, forming a new kind of composite mica pearlescent pigments coated with Co2−xMxTiO4. For the analysis of color and shading power of the pigments, doping of Ni2+ and Zn2+ can improve the color and shading power of the doped pigments, but the larger dosage of Zn2+ doping can weaken the color and shading power of the doped pigments. Doping of Mg2+, Mn2+ and Cu2+ metal ions can also weaken the color and shading power of the doped pigments.  相似文献   

2.
This article addresses the synthesis and characterization of polyaniline (PANI) both in pure and doped forms with various levels of CuCl2 and ZnCl2 in HCl medium where ammonium persulphate was used as an oxidant. Synthesized polymeric materials were characterized spectroscopically (UV‐visible spectroscopy, Fourier transform infrared spectroscopy, and Atomic absorption spectroscopy), thermally (Differential scanning calorimetry), and morphologically (Scanning electron microscopy). Free adsorption energy was calculated via Langmuir adsorption isotherm based on the quantities of Cu2+ and Zn2+ cations in both pre‐ and post‐ polymerization process where it was found that Cu2+ and Zn2+ are adsorbed physically on PANI surface. The dielectric measurements as a function of frequency and temperature showed that conductivity decreased with increasing doping levels of metal cations at high temperatures. POLYM. COMPOS., 31:1862–1868, 2010. © 2010 Society of Plastics Engineers.  相似文献   

3.
《Ceramics International》2016,42(10):11535-11542
Multi-component BaTiO3–Bi0.5Na0.5TiO3–Nb2O5 (BBNN) system doped with divalent metal ions (Zn2+, Co2+, Ni2+) was prepared by the conventional solid–state method.The X-ray diffraction patterns revealed all samples exhibited perovskite (P4mm) single phase. The dielectric properties and micro-mechanisms were discussed and validated. Novel theories, based on the characteristics of the different kinds of dielectric polarization, are proposed to explain the dielectric anomalies in the dielectric system. The relationships between microstructure and the dielectric properties were investigated systematically for the first time. The samples doped with 15 mol% Zn2+/Co2+presented good dielectric properties of an ultra-broad temperature stable range (from −50 and >300), high dielectric constant (ε~1925 for Zn2+/ ε~1341 for Co2+) and low dielectric loss (tan δ<0.02) were obtained. These features made the ceramics system have high practical values for miniaturization and harsh environments applications.  相似文献   

4.
Copolymers (8‐HQ5‐SAOF) were synthesized by the condensation of 8‐hydroxyquinoline 5‐sulphonic acid (8‐HQ5‐SA) and oxamide (O) with formaldehyde (F) in the presence of acid catalyst. Four different copolymers were synthesized by using varied molar proportion of the reacting monomers. Copolymer resin composition has been determined on the basis of their elemental analysis and average molecular weights of these resins were determined by conductometric titration in nonaqueous medium. Viscometric measurement in dimethyl sulphoxide (DMSO) has been carried out with a view to ascertain the characteristic functions and constants. Electronic spectra, FTIR, and proton nuclear magnetic resonance spectra were studied to elucidate the structures. The newly synthesized copolymer proved to be a selective chelating ion‐exchange copolymer for certain metals. The chelating ion‐exchange properties of this synthesized copolymer was studied for different metal ions such as Fe3+, Cu2+, Ni2+, Co2+, Zn2+, Cd2+, and Pb2+. A batch equilibrium method was used in the study of the selectivity of metal ion uptake involving the measurements of the distribution of a given metal ion between the copolymer sample and a solution containing the metal ion only for representative copolymer 8‐HQ5‐SAOF‐I due to economy of space. The study was carried out over a wide pH range, shaking time, and in media of various ionic strengths. The copolymer showed a higher selectivity for Fe3+, Cu2+, and Ni2+ ions than for Co2+, Zn2+, Cd2+, and Pb2+ ions. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010  相似文献   

5.
《分离科学与技术》2012,47(15):3770-3791
Abstract

The present study reports the potential of mango peel waste (MPW) as an adsorbent material to remove Cu2+, Ni2+, and Zn2+ from constituted metal solutions and genuine electroplating industry wastewater. Heavy metal ions were noted to be efficiently removed from the constituted solution with the selectivity order of Cu2+ > Ni2+ > Zn2+. The adsorption process was pH-dependent, while the maximum adsorption was observed to occur at pH 5 to 6. Adsorption was fast as the equilibrium was established within 60 min. Maximum adsorption of the heavy metal ions at equilibrium was 46.09, 39.75, and 28.21 mg g for Cu2+, Ni2+, and Zn2+, respectively. Adsorption data of all the three metals fit well the Langmuir adsorption isotherm model with 0.99 regression coefficient. Release of alkali and alkaline earth metal cations (Na+, K+, Ca2+, Mg2+) and protons H+ from MPW, during the uptake of Cu2+, Ni2+, and Zn2+, and EDX analysis of MPW, before and after the metal sorption process, revealed that ion exchange was the main mechanism of sorption. FTIR analysis showed that carboxyl and hydroxyl functional groups were involved in the sorption of Cu2+, Ni2+, and Zn2+. MPW was also shown to be highly effective in removing metal ions from the genuine electroplating industry effluent samples as it removed all the three metal ions to the permissible levels of discharge legislated by environment protection agencies. This study indicates that MPW has the potential to effectively remove metal ions from industrial effluents.  相似文献   

6.
Cu+2 ion doped polyanilines (PANI) were synthesized by oxidative polymerization of aniline using ammonium persulphate in presence of copper sulphate solution having varying Cu+2 ion concentration. Products were characterized by UV?CVis and FTIR spectroscopy. Morphology of the products was observed by SEM. Morphology of the emeraldine-base form of PANI (EB-PANI) changed when doped with Cu+2 ion and its concentration had also shown influence on the morphology. Thermal stability of the Cu+2 doped PANI was found to be less than that of EB-PANI. Experimental results showed that Cu+2 ions were successfully incorporated into the polymer and there was a strong interaction between the Cu+2 ions and PANI chains. Formation of semiquinone segments (polaron species) upon coordination with Cu+2 ions was undoubtedly demonstrated by UV?CVis and FTIR spectroscopic results. FTIR spectroscopy showed shifts towards the lower wavenumbers for the Cu+2 ion doped PANI as compared to EB-PANI. An increase in intensity of the band at 1,130?cm?1 was observed which corresponds to the electronic like absorption confirming the doping of EB-PANI. Crystallinity was studied by powder XRD analysis and it was found that Cu+2 ion doped PANI has developed a crystalline structure while EB-PANI is amorphous. Conductivity was found to be dependent on the concentration of the Cu+2 ions and there was an optimum concentration of Cu+2 ions for getting the highest conductivity.  相似文献   

7.
This article reports the synthesis, characterization, and ion exchange properties of a terpolymer. The terpolymer resin salicylic acid‐diaminonaphthalein‐formaldehyde (SDNF) was synthesized by the condensation of salicylic acid and diaminonaphthalein with formaldehyde in the presence of a hydrochloric acid catalyst. Terpolymer resin was characterized by elemental analysis, infrared (IR) spectroscopy, nuclear magnetic resonance spectroscopy, and UV–Visible spectral studies. The number average molecular weight of the resin was determined by nonaqueous conductometric titration. Chelation ion exchange properties have also been studied for Fe3+, Cu2+, Ni2+, Co2+, Zn2+, Cd2+, Pb2+ ions employing a batch equilibrium method. It was employed to study the selectivity of metal ion uptake involving the measurements of distribution of a given metal ion between the polymer sample and a solution containing the metal ion. The study was carried out over wide pH range and in a media of various ionic strengths. The terpolymer showed higher selectivity for Fe3+, Cu2+, and Ni2+ions than for Co2+, Zn2+, Cd2+, and Pb2+ ions. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010  相似文献   

8.
Interactions between poly(maleic anhydride‐alt‐acrylic acid), [poly(MA‐alt‐AA)] and Cu2+, Ni2+, and Cd2+ ions were studied by UV–vis spectroscopy and viscosimetry. Effects of nature and the concentrations of the metal ions on the complex formation were investigated and the formation constants of each complex were determined by the mole‐ratio method. UV–vis studies showed that the complex formation tendency increased in the followed order: Cd(II) < Ni(II) < Cu(II). This order was confirmed by the Irving–William series and the Pearson's classification. The influence of metal ions on the reduced viscosity of poly(MA‐alt‐AA) increased in the following order: Cu(II) < Ni(II) < Cd(II), and this result was explained by the concentration effect. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 2698–2705, 2004  相似文献   

9.
The doped polyaniline (PANI) with rare earth ions, which exhibits an increasing conductivity and strongly enhanced fluorescence emission, was prepared by dispersing PANI powder suspension in acetonitrile solution containing rare earth ions according to different mass ratios of rare earth ions to PANI at room temperature. The structure of the doped PANI was characterized by the spectra of FTIR, Raman, UV-vis, and XRD. Red-shifted change for the quinoid and benzenoid stretching vibration is observed in IR and Raman spectra after doping rare earth cations, and UV-vis absorption peak also presents a red-shift, indicating that the doped PANI possesses a better delocalization of electrons along the mainchain backbone. The experimental data show that the electrical and optical behaviors of PANI strongly depend on the species of rare earth cations and their concentration. It is found that enhancing fluorescence for the doped PANI is observed by comparing with emeraldine base (EB). Moreover, the conductivity of the protonated PANI samples doped with Eu3+, Tb3+, and Y3+ ions, increases from 2.1 × 10−4 to 3.33 S cm−1, 1.50 × 10−1 S cm−1 and 2.26 × 10−1 S cm−1. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012  相似文献   

10.
A novel series of visible light‐sensitive Cu2+, Sn2+, and Ag+‐substituted LiMg0.5Ti0.5O2 photocatalysts were synthesized by a facile ion‐exchange method and characterized by XRD, UV‐Vis diffuse reflectance spectra, scanning electron microscopy equipped with an X‐ray energy‐dispersive spectroscopy, Brunauer‐Emmett‐Teller surface area, inductively coupled plasma mass spectrometry, and thermal gravimetric analysis. The characterization results showed that morphology, crystallite size, and surface areas of the ion‐exchange products were almost similar to the parent compound. Absorption edges of Ag+‐doped (AMT), Cu2+‐doped (CMT), and Sn2+‐doped (SMT) samples were red shifted remarkably into the visible light region while parent LiMg0.5Ti0.5O2 (LMT) was UV active. Photocatalytic activity of these samples was evaluated by studying the degradation of methylene blue and nitro benzene under visible light irradiation and the stability of all samples during photocatalytic experiment was also investigated. The activity of all photocatalysts was ranked accordingly as SMT ≥ AMT > CMT > LMT. The correlation between photocatalytic properties, band gap energy, rate of recombination of the charge carriers, and amount of OH radicals generated during photocatalysis and the underlying reasons were discussed.  相似文献   

11.
A copolymer (4‐HAOF) prepared by condensation of 4‐hydroxyacetophenone and oxamide with formaldehyde in the presence of an acid catalyst proved to be a selective chelating ion‐exchange copolymer for certain metals. Chelating ion‐exchange properties of this copolymer were studied for Fe3+, Cu2+, Ni2+, Co2+, Zn2+, Cd2+, Pb2+, and Hg2+ ions. A batch equilibrium method was employed in the study of the selectivity of metal‐ion uptake involving the measurements of the distribution of a given metal ion between the copolymer sample and a solution containing the metal ion. The study was carried out over a wide pH range and in media of various ionic strengths. The copolymer showed a higher selectivity for Fe3+ ions than for Co2+, Zn2+, Cd2+, Pb2+, Cu2+, Ni2+, and Hg2+ ions. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 787–790, 2003  相似文献   

12.
Trichoderma reesei was used as a biosorbent for the removal of Co2+, Cu2+, Ni2+, Pb2+ and Zn2+ ions. The influence of factors such as pH, mass of biomass, contact time and temperature on biosorption efficiency was optimized. To calculate the isotherm parameters for the biosorption of Co2+, Cu2+, Ni2+, Pb2+ and Zn2+ ions at optimized conditions, the experimental equilibrium data were fitted to Langmuir and Freundlich models. The calculated thermodynamic parameters, ΔG°, ΔH° and ΔS° showed that the biosorption of Co2+, Cu2+, Ni2+, Pb2+ and Zn2+ ions onto T. reesei biomass was feasible, spontaneous and endothermic at the optimized conditions. The results of kinetic analysis showed that the biosorption of the selected metal ions onto T. reesei biomass obeys pseudo second order kinetics.  相似文献   

13.
A series of graphene/polyaniline-M2+ (M2+ = Mn2+, Co2+, Ni2+, and Cu2+) composite counter electrodes were synthesized by doping transition-metal ions in polyaniline and graphene for dye-sensitized solar cells (DSSCs). The counter electrodes showed significantly high photoelectric conversion efficiency of 5.38% (Mn2+), 4.65% (Co2+), 4.00% (Ni2+), and 2.49% (Cu2+). The catalytic activities of graphene/polyaniline-M2+ electrodes were evaluated using cyclic voltammetry, Nyquist plots, and Tafel polarization. The chemical characteristics and surface morphology of graphene/polyaniline-M2+ composite materials were determined by infrared spectroscopy and scanning electron microscopy. These results indicate a potential application of ion-doped polyaniline as the counter electrode in cost-effective DSSCs.  相似文献   

14.
An ion‐exchange resin containing carboxylic acid groups was prepared by reaction of epoxidized soybean oil with triethylene tetramine, followed by hydrolysis of glycerides by using sodium hydroxide solution. The cation exchange capacity of the resins was determined to be 3.50 mequiv/g. The adsorption capacity for Cu2+, Ni2+, and Co2+ on the obtained resin at pH 5.0 was found to be 192, 96, and 78 mg/g, respectively. Effect of pH on the adsorption capacity for copper (II), nickel (II), and cobalt (II) ions were also studied. Cu2+, Ni2+, and Co2+ were adsorbed at a pH above 3. These metal ions adsorbed on the resin are easily eluted by using 1N HCl solution. The selectivity of the resin for Cu2+ from mixtures containing Cu2+/Co2+/Ni2+ ions in the presence of sodium chloride was also investigated © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 2386–2396, 2002  相似文献   

15.
Ultraviolet/visible (UV/vis) spectroscopy was used to determine qualitatively and quantitatively Cu2+, Co2+, Co3+, and Fe3+ in oxidized Cu–Co ore leachates. The mineralogical and chemical characteristics of the three oxidized Cu–Co ore samples considered were determined using Fourier transform infrared spectroscopy (FTIR), X-ray powder diffractometry (XRD), scanning electron microscopy-energy dispersive spectroscopy (SEM-EDS), and X-ray fluorescence spectrometry (XRF). The results showed that Cu and Co in the samples were in the form of carrollite (Co2CuS4), malachite (Cu2CO3(OH)2, and heterogenite (CoO(OH)). The samples contained (2.73% Cu and 0.19% Co), (2.82% Cu and 0.07% Co), and (0.03% Cu and 0.05% Co), respectively. Gangues were mainly constituted of quartz, goethite, and hematite. The ultraviolet/visible (UV/vis) results indicated that the wavelengths of absorbance of the metal ions in dilute ethylenediaminetetraacetic acid aqueous solution (pH ≈ 3.5) were Fe3+ (293 nm), Cu2+ (821 nm), Co3+ (344 nm), and Co2+ (512 nm). The molar concentrations of the metal ions obtained using the UV/vis method compared well with the results obtained using the atomic absorption spectroscopy (AAS) method. UV/vis spectroscopy was also used to monitor the conversion of Co3+ into Co2+ using different reducing agents. The results showed that the molar concentration of Co2+ in the aqueous solutions increased with the addition of reducing agents, of about 80.95% (copper foil), 61.22% (ferrous sulfate), and 20.35% (sodium sulfite), respectively.  相似文献   

16.
A novel terpolymer involving 2‐amino‐6‐nitrobenzothiazole and ethylenediamine with formaldehyde was synthesized by a polycondensation technique using glacial acetic acid as a reaction medium. The resulting chelating terpolymer resin was characterized using elemental analysis, physicochemical parameters, and UV‐visible, Fourier transform infrared, 1H NMR and 13C NMR spectral studies. Average molecular weights of the terpolymer were determined using gel permeation chromatography. The surface morphology and the nature of the terpolymer were investigated using scanning electron microscopy and X‐ray diffraction. The chelation ion‐exchange property of the terpolymer was determined against some common metal ions such as Fe3+, Co2+, Ni2+, Cu2+, Zn2+ and Pb2+ using the batch equilibrium method. Effects of parameters such as the pH, contact time and various electrolyte concentrations were studied. The reusability of the terpolymer was checked in terms of its effective repeated usage. The results of the Langmuir and Freundlich adsorption isotherm models were best fitted with each other and the reaction kinetics followed pseudo second‐order kinetics. The terpolymer showed good results against Fe3+, Cu2+ and Ni2+ ions compared to those against the other metal ions. © 2014 Society of Chemical Industry  相似文献   

17.
The poly‐o‐toluidine (POT) was prepared under different magnetization in solution containing 0.5 mol dm?3o‐toluidine, 1.0 mol dm?3 HCl with and without 0.5 mol dm?3 DyCl3, respectively. Their conductivity, UV–vis, FTIR spectra, X‐ray diffraction (XRD), thermogravimetric analysis (TGA), and scanning electron microscope (SEM) were investigated. The results of conductivity showed that magnetic field and the cooperative effect of Dy3+ and magnetic field do obvious effect to conductivity of POT. Meantime, they also can make the energy for the π–π* transitions and quinoid ring transition in UV–vis spectra smaller. At high magnetization the peaks of POT due to Q? NH+? B or B? NH+? B and C? H out of plane on 1,4‐ring or 1,2,4‐ring disappeared in FTIR spectra. Magnetic field and Dy3+ can make three dimensions morphologies of the POT clear, but they scarcely affect the crystallinity of POT. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 2174–2179, 2007  相似文献   

18.
Experimental studies on the retention of cadmium (Cd2+), copper (Cu2+), nickel (Ni2+), and lead (Pb2+) by bentonite samples from Iran were conducted using single- and multiple-component solutions. Based on the sorption capacity of bentonite the following order was obtained for single- and multiple-component solutions: Pb2+ > Cd2+ > Ni2+ > Cu2+. The maximum adsorption capacities of bentonite with metals in single- and multiple-component solutions were 29.5%, 22.5%, 19.2%, and 17.1% and 13.5%, 13.4%, 12.1%, and 9.1% for Pb2+, Cd2+, Ni2+, and Cu2+, respectively. Desorption isotherms of Cd2+, Cu2+, Ni2+, and Pb2+ deviated significantly from the sorption isotherms, thereby indicating irreversible or very slowly reversible sorption. Finally, soil solution saturation indices and metal speciation were assessed using the Visual MINTEQ 2.6 program and the probability of mineral precipitation was supported by scanning electron microscopy.  相似文献   

19.
A fluorescent conjugated polymer was synthesized by the polymerization of 1,4‐dibromo‐2,3‐bisbutoxynaphthalene ( M‐2 ) with 5,5′‐divinyl‐2,2′‐bipyridine ( M‐3 ) via Heck reaction. The conjugated polymer shows strong blue–green fluorescence because of the extended π‐electronic structure between the repeating unit 2,3‐bisbutoxynaphthyl group and the conjugated linker 2,2′‐bipyridyl (bpy = 2,2′‐bipyridine) moiety via vinylene bridge. The responsive properties of the conjugated polymer on transition metal ions were investigated by fluorescent and UV–vis spectra. The results show that Cu2+ and Ni2+ can form nonradiative metal‐to‐ligand charge‐transfer complexes with the polymer, whereas, Zn2+ and Cd2+ do not produce the pronounced differences from the polymer fluorescence and UV–vis spectra. The fluorescent quenching can probably be attributed to the intramolecular photoinduced electron transfer (PET) or photoinduced charge transfer (PCT). The results can also suggest that 2,2′‐bipyridyl moiety in the main chain backbone of the conjugated polymer can act as the recognition site of a special fluorescent chemosensor for sensitive detection of transition metal ions. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009  相似文献   

20.
Coordination polymers containing bisphenol‐A, formaldehyde, and transition metal complexes of ethylenediamine [M(en)2] were synthesized by the reaction of bisphenol‐A, formaldehyde, and M(en)2 complex in alkaline medium, using M for Fe+3, Co+2, Ni+2, Cu+2, and Zn+2. The materials were characterized by elemental analysis, FTIR, UV–Vis, 1H‐NMR spectra, TGA, and magnetic susceptibility measurement. The geometry of the central metal ions was determined by electronic spectral studies and magnetic moment measurement. The M N and C N bonds were confirmed by the IR spectra of the polychelates. The 1H‐NMR spectra of the chelating resins confirmed polycondensation with well‐defined peaks for bridging methylene functions. Complexation studies with transition metal ions revealed effective coordination of the bisphenol‐A formaldehyde resin. The antimicrobial activities of these chelated resins were screened against E. coli, S. dysantrea (bacteria), and C. albicans, A. niger (fungi) by using agar well diffusion method. All the polymeric chelates show promising antimicrobial activities. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011  相似文献   

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