Study on the Adsorption Behavior of Co(II), Pb(II) on Modified Sodium Trititanate Whisker and Its Application to Wastewater
The modification of sodium trititanate whisker surface was performed by means of impregnation procedure to fabricate the modified sodium trititanate whisker, which was characterized by scanning electron microscopy(SEM) and infrared spectroscopy(IR). Its adsorptive performance for Co(II), Pb(II) in a static system was investigated by inductively coupled plasma atomic emission spectrometry(ICP-AES). The main factors affecting adsorption and desorption of Co(II), Pb(II), the adsorptive capacity of Co(II), Pb(II) in optimal condition and adsorption isotherm and the influence of coexistent ions were examined. The comparative test for selectivity was done. The adsorptive rate for Co(II) and Pb(II) on 0.2500 g of modified sodium trititanate whisker at PH 5.0 was the best. Co(II), Pb(II) adsorbed on the modified sodium tretitanate whisker could be eluted with 10 mL of 3.0 mol/L HCl. The adsorptive performance of modified sodium trititanate whisker was better than that of unmodified sodium trititanate whisker. The sobent has been applied to the enrichment and separation of Co(II), Pb(II) in water sample to determine Co(II), Pb(II).
Preparation and photocatalytic activity of alkali titanate nano materials A2TinO2n+1 (A=Li, Na and K)
Photocatalysts nano A{sub 2}Ti {sub n}O{sub 2n+1} (A = Li, Na, K) were prepared successfully by novel hydrothermal synthesis process. Powders were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), ultraviolet-visible (UV-vis) absorption spectra and field-emission scanning electron microscope (FE-SEM) measurements. These results showed that the compositions of lithium, sodium and potassium titanates were Li{sub 2}TiO{sub 3}, Na{sub 2}Ti{sub 3}O{sub 7} and K{sub 2}Ti{sub 8}O{sub 17}, respectively. The nano crystals of Li{sub 2}TiO{sub 3} were self-assembled as snowflakes while that of Na{sub 2}Ti{sub 3}O{sub 7} and K{sub 2}Ti{sub 8}O{sub 17} were nanorods. Photocatalytic properties of alkali titanates were also investigated. The results indicated that alkali titanates as prepared have higher photocatalytic activities compared with P25 TiO{sub 2} in the degradation of chloroform under UV light irradiation. A combination of K{sub 2}Ti{sub 8}O{sub 17} and NiO produces a photocatalyst effective for the degradation of chloroform in aqueous solution. The framework of the tunnel structure was suitable for accommodating cocatalysts such as NiO to induce a strong interaction between the active species and cocatalysts. Na{sub 2}Ti{sub 3}O{sub 7} has high photocatalytic activity under visible-light irradiation due to its strong absorption in the visible light region. The photocatalytic properties of Li{sub 2}TiO{submore » 3} are inferior to that of Na{sub 2}Ti{sub 3}O{sub 7} and K{sub 2}Ti{sub 8}O{sub 17} due to its mono-perovskite structure.« less
An anionic inositol phosphate glycan pseudotetrasaccharide exhibits high insulin-mimetic activity in rat adipocytes.
Inositol phosphate glycan pseudotetrasaccharides consisting of man-(alpha1-6)-man-(alpha1-4)-glcN-(alpha,beta1-6)-myo-inositol-1,2-cyclic phosphate possessing a sulfate group at either O-6 (compounds 3alpha,beta) or O-2 (compounds 4alpha,beta) of the terminal mannose have been prepared. Compound 4alpha was able to stimulate lipogenesis in native rat adipocytes to 78% of the maximal insulin response (MIR) with an EC50 of 1.1 microM. The other compounds exhibited lower maximal stimulations (47-63% MIR) and higher EC50 values (9.5-10.6 microM).