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171.
Suhaina Mohd Ibrahim Abdul Kadir Masrom Babak Mazinani Shahidan Radiman Farinaa Md Jamil Ali Beitollahi Nobuaki Negishi Noorhana Yahya 《Research on Chemical Intermediates》2013,39(3):1003-1014
Mesoporous TiO2 has been synthesized by the sol–gel method, using a nonionic triblock copolymer P123 as surfactant template under acidic conditions. The as-prepared samples were characterized by thermogravimetry–differential thermal analysis (TG–DTA), nitrogen absorption–desorption (BET), field emission scanning electron microscopy, and transmission electron microscopy. The photocatalytic activity of the mesoporous TiO2 was evaluated by degradation of methylene blue under high-intensity UV light irradiation; the amount of methylene blue was measured by UV–visible spectroscopy. TG–DTA analysis revealed that the surfactant had been removed partly in as-synthesized samples. BET analysis proved that all the samples retained mesoporosity with a narrow pore-size distribution (4.5–6.3 nm) and high surface area (103–200 m2/g). All calcined mesoporous TiO2 had high photocatalytic activity in the photodegradation of methylene blue. 相似文献
172.
Sadin Özdemir Veysi Okumuş Abdurrahman Dündar Kadir Serdar Çelik Uyan Yüksel 《International journal of environmental analytical chemistry》2013,93(6):533-545
Coriolus versicolor, a wood fungus, was immobilised on Amberlite XAD-4 and used as solid-phase biosorbent for preconcentrations of rare earth elements. La(III), Th(IV), U(IV) and Ce(III) were subjected to solid-phase extraction procedure. We observed that La(III) was selectively preconcentrated, while other ions remained in solution at pH 6.0. 5.0 mL of 1.0 mol L?1 HCl was used to elaute La(III) from column. 250 mg of C. versicolor loaded on 1000 mg of XAD-4 was optimised as solid-phase matrix. Concentrations of ions in solutions were determined by inductively coupled plasma– optical emission spectrometry (ICP-OES). The calibration plot after preconcentration was linear in the range from 1.0 to 50.0 ng mL?1 for La(III). Limit of detection was found as 0.27 ng mL?1 for La(III) by SPE method. Relative standard deviation was found lower than 6.7% for 1.0 ng mL?1 of La(III) solution (n = 10). The sensitivity of ICP-OES was improved by a factor of 46.8. The applicability of the method was validated through the analysis of certified reference samples of tea (NCS ZC-73014) and spinach (NCS ZC-73013). 相似文献
173.
U?ur?Tamer Yusuf?Gündo?du ?smail?Hakk??Boyac? Kadir?Pekmez 《Journal of nanoparticle research》2010,12(4):1187-1196
The production of monodispersed magnetic nanoparticles with appropriate surface modification has attracted increasing attention
in biomedical applications including drug delivery, separation, and purification of biomolecules from the matrices. In the
present study, we report rapid and room temperature reaction synthesis of gold-coated iron nanoparticles in aqueous solution
using the borohydride reduction of HAuCl4 under sonication for the first time. The resulting nanoparticles were characterized with transmission electron microscopy
(TEM), electron spectroscopy for chemical analysis (ESCA), ultraviolet visible spectroscopy (UV–Vis), and X-ray diffraction
(XRD). Surface charges and magnetic properties of the nanoparticles were also examined. The pattern of Fe3O4 nanoparticles is face centered cubic with an average diameter of 9.5 nm and the initial reduction of gold on the surface
of Fe3O4 particles exhibits uniform Fe3O4–Au nanoparticles with an average diameter of 12.5 nm. The saturation magnetization values for the uncoated and gold-coated
Fe3O4 nanoparticles were found to be 30 and 4.5 emu/g, respectively, at 300 K. The progression of binding events between boronic
acid terminated ligand shell and fructose based on the covalent bonding interaction was measured by absorbance spectral changes.
Immunomagnetic separation was also performed at different E. coli concentration to evaluate capturing efficiency of resulting nanoparticles. Immunomagnetic separation percentages were varied
in a range of 52.1 and 21.9% depend on the initial bacteria counts. 相似文献
174.
Dextran-chitosan blend added with ammonium thiocyanate (NH4SCN)-based solid polymer electrolytes are prepared by solution cast method. The interaction between the components of the electrolyte is verified by Fourier transform infrared (FTIR) analysis. The blend of 40 wt% dextran-60 wt% chitosan is found to be the most amorphous ratio. The room temperature conductivity of undoped 40 wt% dextran-60 wt% chitosan blend film is identified to be (3.84?±?0.97)?×?10?10 S cm?1. The inclusion of 40 wt.% NH4SCN to the polymer blend has optimized the room temperature conductivity up (1.28?±?0.43)?×?10?4 S cm?1. Result from X-ray diffraction (XRD) and differential scanning calorimetry (DSC) analysis shows that the electrolyte with the highest conductivity value has the lowest degree of crystallinity (χ c) and the glass transition temperature (T g), respectively. Temperature-dependence of conductivity follows Arrhenius theory. From transport analysis, the conductivity is noticed to be influenced by the mobility (μ) and number density (n) of ions. Conductivity trend is further verified by field emission scanning electron microscopy (FESEM) and dielectric results. 相似文献