Pure K2Ti4O9 whiskers were prepared by KDC(Kneading-Drying-Calcination) method with TiO2 and K2CO3 as raw materials. The influences of TiO2/K2CO3 molar ratio(RT/K), calcination temperature(TC) and cooling proces...Pure K2Ti4O9 whiskers were prepared by KDC(Kneading-Drying-Calcination) method with TiO2 and K2CO3 as raw materials. The influences of TiO2/K2CO3 molar ratio(RT/K), calcination temperature(TC) and cooling process on phase composition and morphology of the whiskers were investigated by TG-DSC(thermo gravimetric-differential scanning calorimeter), XRD(X-ray diffraction), and SEM(scanning electron microscope). Pure K2Ti4O9 potassium titanate whiskers with large length-diameter ratio(r)(over 250) can be obtained at RT/K = 2.9 and TC = 950 ℃.展开更多
The spectrophotometric characteristic of a new reagent 1, 4, 9, 12-tetraaza Cyclo-2, 3, 6, 7, 10, 11, 14, 15 tetrabenzocetanan-5, 8, 13, 16-tetraone (TCTCT) and its complex with Cu(Ⅱ) were studied. The reagent and i...The spectrophotometric characteristic of a new reagent 1, 4, 9, 12-tetraaza Cyclo-2, 3, 6, 7, 10, 11, 14, 15 tetrabenzocetanan-5, 8, 13, 16-tetraone (TCTCT) and its complex with Cu(Ⅱ) were studied. The reagent and its complex with Cu(Ⅱ) have a similar maximum absorbance at 446 um. In C6H4(C2O4HK)-NaOH buffer (pH=4.00), the complex of Cu(Ⅱ)-TCTCT formed when it was heated. The absorbance increased with the increase of the concentration of Cu(Ⅱ) in the range of 1 .6x10-7-5.5x 10-5 mol/L. The composition ratio of the complex was formed to be 1: 1 using the molar ratio method. The method was simple, rapid and sensitive, giving an apparent molar absorptivity of 1.25x105 L mol-1 cm-1 and the apparent stability constant of 1 .04x106. The method was directly applied of copper in fresh milk.展开更多
基金Funded by the Natural Science Foundation Key Project of Hubei Province(No.2011CDA060)
文摘Pure K2Ti4O9 whiskers were prepared by KDC(Kneading-Drying-Calcination) method with TiO2 and K2CO3 as raw materials. The influences of TiO2/K2CO3 molar ratio(RT/K), calcination temperature(TC) and cooling process on phase composition and morphology of the whiskers were investigated by TG-DSC(thermo gravimetric-differential scanning calorimeter), XRD(X-ray diffraction), and SEM(scanning electron microscope). Pure K2Ti4O9 potassium titanate whiskers with large length-diameter ratio(r)(over 250) can be obtained at RT/K = 2.9 and TC = 950 ℃.
基金The work was financially supported by the National Natural Science Foundation of China and the New Materials Study Project of Northwest Normal University, China.
文摘The spectrophotometric characteristic of a new reagent 1, 4, 9, 12-tetraaza Cyclo-2, 3, 6, 7, 10, 11, 14, 15 tetrabenzocetanan-5, 8, 13, 16-tetraone (TCTCT) and its complex with Cu(Ⅱ) were studied. The reagent and its complex with Cu(Ⅱ) have a similar maximum absorbance at 446 um. In C6H4(C2O4HK)-NaOH buffer (pH=4.00), the complex of Cu(Ⅱ)-TCTCT formed when it was heated. The absorbance increased with the increase of the concentration of Cu(Ⅱ) in the range of 1 .6x10-7-5.5x 10-5 mol/L. The composition ratio of the complex was formed to be 1: 1 using the molar ratio method. The method was simple, rapid and sensitive, giving an apparent molar absorptivity of 1.25x105 L mol-1 cm-1 and the apparent stability constant of 1 .04x106. The method was directly applied of copper in fresh milk.