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31.
M. H. Mallah M. Ghannadi Maragheh A. Badiei R. Habibzadeh Sbo 《Journal of Radioanalytical and Nuclear Chemistry》2010,283(3):597-601
In the present work, results of γ-irradiation on normal and functionalized SBA-15 by aurintricarboxylic acid have been reported.
Characterization of normal and functionalized SBA-15 particles before and after γ-irradiation was carried out using Fourier-transform
infrared technique. Aurintricarboxylic acid ligand connected to SBA-15 was also analyzed using UV/Vis spectrophotometer. The
modified sorbent was then used as a new sorbent for separation of trace amounts of praseodymium and lutetium ions from nuclear
waste waters in batch techniques. Based on the results of distribution coefficients determination, and investigation of sorption
process in various conditions, the parameters were optimized for separation lanthanides. It can be concluded that the functionalized
SBA-15 is a promising sorbent for praseodymium and lutetium cations. 相似文献
32.
Morteza Hosseini Vinod Kumar Gupta Mohammad Reza Ganjali Zahra Rafiei-Sarmazdeh Farnoush Faridbod Hassan Goldooz Ali Reza Badiei Parviz Norouzi 《Analytica chimica acta》2012
A novel fluorescence nano-chemosensor for Cr2O72− anion has been developed by assembly of fluorescent aluminum complex of 8-hydroxyquinoline (AlQx) within the channels of modified SBA-15. SBA-SPS-AlQx shows a fluorescence emission at 486 nm. The observed remarkable fluorescence of SBA-SPS-AlQx quenches in presence of Cr2O72− anion. The results showed that this fluorescent nano-material can be a useful chemo-sensor for determination of dichromate anions in aqueous solutions. The linear detecting range of fluorescent nano-chemosensor for Cr2O72− anion was 0.16–2.9 μmol L−1. The lowest limit of detection (LDL) was also found to be 0.2 ng mL−1 in aqueous solutions. SBA-SPS-AlQx showed selectively and sensitively fluorescent quenching response toward Cr2O72− ion in comparison with I3−, NO3−, CN−, CO32−, Br−, Cl−, F−, H2PO4− and SO42− ions, which was because of the higher stability of its inorganic complex with dichromate ion. 相似文献
33.
Strontium hexaferrite is a hard magnetic material and has been extensively used as a permanent magnet. In this work, a novel sol–gel auto-combustion method was used to synthesize ultra-fine strontium hexaferrite, and the effect of the surfactant on the crystallite size of the final product was investigated for the first time. The DTA/TGA plot exhibited the formation temperature of hexaferrite. The XRD results show that adding surfactant to the sol does not change the composition of the combustion product and the surfactant burns completely during the combustion process. The average crystallite size of hexaferrite powders was also measured by the X-ray line broadening technique employing the Scherrer formula. The results show that adding surfactant to the gel makes the particle size of the final product much smaller. 相似文献
34.
Morteza Hosseini Mohammad Reza Ganjali Zahra Rafiei-Sarmazdeh Farnoush Faridbod Hassan Goldooz Alireza Badiei Parviz Nourozi Ghodsi Mohammadi Ziarani 《Analytica chimica acta》2013
A new Lu3+ sensitive fluorescent chemosensor is designed using 8-hydroxyquinoline functionalized mesoporous silica with highly ordered structure (LUS-SPS-Q). The characterization of LUS-SPS-Q showed that the organized structure has been preserved after the post grafting procedure. The synthesized material showed a selective interaction with Lu3+ ion, most probably due to the presence of the fluorophore moiety at its surface. The emission intensity of the Lu3+-bound mesoporous material increases with an increase in concentrations of Lu3+ ion. Addition of other mono-, di-, trivalent ions resulted in insignificant change in the fluorescent intensity. The enhancement of fluorescence is attributed to the strong covalent binding of Lu3+ ion. The linear response range of Lu3+ chemo-sensor was from 1.6 × 10−7 to 1.0 × 10−5 mol L−1. The Limit of detection obtained was 8.2 × 10−8 mol L−1 and the pH range which the proposed chemo-sensor can be applied was 3.3–8.3. 相似文献
35.
Payman Hashemi Alireza Badiei Mohammad Shamizadeh Ghodsi Mohammadi Ziarani Ali Reza Ghiasvand 《中国化学会会志》2012,59(6):727-732
LUS‐1 typed nanoporous silica particles were synthesized and silylated with hexamethyldisilazane and investigated as a highly porous fiber coating for solid‐phase microextraction (SPME). The pore size distribution of the prepared Sil‐LUS‐1 was still typical of MCM‐41 and centered at 3 nm with a specific surface area of 720 m2g?1. The SPME fiber was prepared by liming the material on a copper wire. The extraction efficiency of the new fiber was compared with a commercial PDMS fiber for headspace extraction and GC‐MS analysis of phenol, 4‐nitrophenol, 2,4‐dichlorophenol and 4‐chlorophenol in water samples. Due to the high porosity of the prepared fiber it showed a higher sensitivity and better selectivity for the extraction of the target compounds. For optimization of different factors affecting the extraction efficiency, a simplex optimization method was used. The relative standard deviation for the measurements by one fiber was better than 7% for five replicates and the fiber‐to‐fiber reproducibility was about 10% for five fabricated fibers. Detection limits in the range of 0.002 to 0.026 μg mL?1 were obtained for the phenolic compounds. The fiber was successfully applied for the determination of phenolic compounds in natural water samples. 相似文献
36.
Sheykhan M Heydari A Ma'mani L Badiei A 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2011,83(1):379-383
Pure homogeneous nano sized biocompatible fluorapatite (FAp) particles were synthesized by a wet chemical procedure using water soluble tetra-butylammonium fluoride (TBAF) without using high temperatures and any purification processes. Combination of the Bragg's law and the plane-spacing equation for the two high intensity lines, namely, (002) and (300), gives a=9.3531 ?, c=6.8841 ?, confirms the identity of the highly crystalline synthetic material as well as its purity. The effect of various pH's in crystal formation and on their size was also evaluated. The calculated crystallinities were excellent with a rate around 5.0. The synthesized nano FAp was fully characterized by spectroscopic techniques (XRD, SEM, EDS, BET, FT-IR and ICP-AES). The nitrogen adsorption-desorption isotherm showed a type IV diagram and calculation of the surface area was investigated as well. 相似文献
37.
Ganjali MR Hosseini M Memari Z Faridbod F Norouzi P Goldooz H Badiei A 《Analytica chimica acta》2011,708(1-2):107-110
Bis(8-hydroxy quinoline-5-solphonate) cerium(III) chloride (Ce(QS)(2)Cl) (L) was synthesized and then used as a novel fluorescent sensor for anion recognition. Preliminarily study showed that fluorescence of L enhanced selectively in the presence of HPO(4)(2-) ion. This enhancement is attributed to a 1:1 complex formation between L and HPO(4)(2-) anion. The association constant of 1:1 complex of L-HPO(4)(2-) was calculated as 3.0×10(6). Thus, L was utilized as a basis for a selective detection of HPO(4)(2-) anion in solution. The linear response range of the proposed fluorescent chemo-sensor covers a concentration range of HPO(4)(2-) from 3.3×10(-7) to 5.0×10(-6) mol L(-1) with a detection limit of 2.5×10(-8) mol L(-1). L showed selective and sensitive fluorescence enhancement response toward HPO(4)(2-) ion in comparison with I(3)(-), NO(3)(-), CN(-), CO(3)(2-), Br(-), Cl(-), F(-), H(2)PO(4)(-) and SO(4)(2-) ions. It was probably attributed to the higher stability of the inorganic complex between HPO(4)(2-) ion and L. The method was successfully applied for analysis of phosphate ions in some fertilizers samples. 相似文献
38.
A metal?Corganic framework complex, [Co(??3?Ctp)(??2?pyz)] n , where H2tp?=?1,4-benzenedicarboxylic acid (terephthalic acid) and pyz?=?pyrazine, has been synthesized under hydrothermal conditions and characterized by physico-chemical and spectroscopic methods, thermogravimetric analysis and single-crystal X-ray diffraction. Each Co(II) center is surrounded by four carboxylate oxygen atoms from three tp ligands and two nitrogen atoms from two pyrazine ligands, giving a distorted octahedral geometry. The entire framework is made up of two-dimensional sheets of dicobalt ions linked via terephthalate ligands to form rectangles. The sheets are then linked into each other via the axial pyrazine ligands, forming an interlocked 3-D network, which is finally arranged as an ABAB interconnected pattern. Photoluminescence measurements for the polymer in the solid state show an emission at 414?nm, which suggests this complex as a potential blue-light material. The electrochemical behavior of a modified carbon paste electrode prepared from the complex has been studied by cyclic voltammetry, indicating quasi-reversible redox behavior. 相似文献
39.
Photo and Chemical Reduction of Copper onto Anatase‐Type TiO2 Nanoparticles with Enhanced Surface Hydroxyl Groups as Efficient Visible Light Photocatalysts 下载免费PDF全文
Hamed Eskandarloo Alireza Badiei Mohammad A. Behnajady Ghodsi Mohammadi Ziarani 《Photochemistry and photobiology》2015,91(4):797-806
In this study, the photocatalytic efficiency of anatase‐type TiO2 nanoparticles synthesized using the sol–gel low‐temperature method, were enhanced by a combined process of copper reduction and surface hydroxyl groups enhancement. UV–light‐assisted photo and NaBH4‐assisted chemical reduction methods were used for deposition of copper onto TiO2. The surface hydroxyl groups of TiO2 were enhanced with the assistance of NaOH modification. The prepared catalysts were immobilized on glass plates and used as the fixed‐bed systems for the removal of phenazopyridine as a model drug contaminant under visible light irradiation. NaOH‐modified Cu/TiO2 nanoparticles demonstrated higher photocatalytic efficiency than that of pure TiO2 due to the extending of the charge carriers lifetime and enhancement of the adsorption capacity of TiO2 toward phenazopyridine. The relationship of structure and performance of prepared nanoparticles has been established by using various techniques, such as XRD, XPS, TEM, EDX, XRF, TGA, DRS and PL. The effects of preparation variables, including copper content, reducing agents rate (NaBH4 concentration and UV light intensity) and NaOH concentration were investigated on the photocatalytic efficiency of NaOH‐modified Cu/TiO2 nanoparticles. 相似文献
40.
Jalal Poostforooshan Alireza Badiei Gholamali Farzi Hassan Goldooz Alfred P. Weber 《Chemical Papers》2017,71(10):1887-1894
In this work, for the first time, control over the position of maximum emission peak for fluorophore, using embedded tris(8-hydroxyquinoline) aluminum (AlQ3) complexes into different types of host materials, can be achieved. Moreover, the environmental and concentration effects on luminescent properties were studied. In this regard, different concentrations of AlQ3 were embedded into the poly(methyl methacrylate-co-butyl acrylate) (PMMA-co-PBuA) nanoparticles as organic host materials by emulsion polymerization. It is established that the dilution of AlQ3 in the polymer matrix leads to blue-shift of the luminescence maximum up to 0.32 eV compared to pure AlQ3. Moreover, AlQ3 was embedded in SBA-15 type mesoporous silica as an inorganic host material by physical adsorption. Finally, this functionalized mesoporous silica was incorporated into PMMA-co-PBuA transparent matrix by blending method to obtain Co-Poly-AlQ3-SBA-15 as organic–inorganic composite material. It was found that there is no significant wavelength shift on the maximum emission peak of the organic–inorganic composite at various concentrations of AlQ3-SBA-15. The prepared materials were characterized by powder X-ray diffraction (XRD), N2 adsorption–desorption, NMR, Fourier transform infrared (FT-IR), dynamic light scattering (DLS), scanning electron microscopy (SEM) and fluorescence spectra. 相似文献