Copper(Ⅱ) oxides powder catalysts were prepared by three different methods,thermal decomposition,solid phase reaction and chemical precipitation.The phase,surface structure,morphology,particle size and catalytic acti...Copper(Ⅱ) oxides powder catalysts were prepared by three different methods,thermal decomposition,solid phase reaction and chemical precipitation.The phase,surface structure,morphology,particle size and catalytic activity of the powder for H 2O 2 decomposition were investigated by XRD,SEM,FT IR and the surface area measurement techniques.These studies revealed that high low sequence of catalytic activity of powder prepared by three different methods is opposite from their surface area,and that catalytic activity of the powder is principally related to its surface structure and active compositions.展开更多
A highly sensitive fluorescence quenching method for the determination of chromium(VI)based on the system of Cr(VI)OFluorophenylfluorone(OFPF)cetyltrimethylammonium bromide(CTMAB)sodium tartrate(Tartrate)was developed...A highly sensitive fluorescence quenching method for the determination of chromium(VI)based on the system of Cr(VI)OFluorophenylfluorone(OFPF)cetyltrimethylammonium bromide(CTMAB)sodium tartrate(Tartrate)was developed.In a pH 420～480 medium of HAcNaAc,chromium(VI)reacts with OFPF,CTMAB and Tartrate to form a nonfluorescent mixed complex and quenches the fluorescence intensity of OFPF.There is a linear relationship between fluorescence quenching intensity and concentration of chromium(VI)from 0 to 02μg/25ml.The detection limit for Cr(VI)is 01μg/L.The method has been applied to the determination of trace chromium(VI)in water samples with satisfactory results.展开更多
Ultrafine Powder CuO was prepared by direct-heating Cu2(OH)2CO3 in differe nt calcination temperatures. XRD, FT-IR, SEM and surface area measurement tech niques were used to investigate the properties of the CuO powde...Ultrafine Powder CuO was prepared by direct-heating Cu2(OH)2CO3 in differe nt calcination temperatures. XRD, FT-IR, SEM and surface area measurement tech niques were used to investigate the properties of the CuO powder. The results sh ow that the decomposition temperature has remarkably effect on crystallite size, morphology, surface structure, IR behavior and activity of the powder for H2O2 decomposition. The major morphology of the particle is fluffy-sphered in the l ower temperature, which is consists of small sheets of crystallite. With the inc reasing of calcination temperature, crystal of CuO grows up, the fluffy-sphere d particle reduces and catalytic activity decreases. FT-IR patterns revealed t hat the absorption of Cu-O and -OH bond in CuO ultrafine powder were red-s hifted.展开更多
The distribution of mitomycin(MIT) for injection in aqueous surfactant two phases(ASTP), consisted of cetyltrimethylammonium bromide(CTAB) and sodium oleate(SO) has been studied by spectrophotometry. The results show ...The distribution of mitomycin(MIT) for injection in aqueous surfactant two phases(ASTP), consisted of cetyltrimethylammonium bromide(CTAB) and sodium oleate(SO) has been studied by spectrophotometry. The results show that for ASTP system with a certain ratio of CTAB to SO the volume of the upper phase decreased and that of the lower phase increased with increase of MIT added, while the distribution ratio K d and single extraction yield Y of MIT in two phases remained approximately constant.展开更多
Nanopowder MnO 2 was prepared with two oxidation reduction methods.XRD,SEM,FT IR and surface area measurement techniques were used to investigate properties of the MnO 2 powder.The results showed that the nano MnO 2 w...Nanopowder MnO 2 was prepared with two oxidation reduction methods.XRD,SEM,FT IR and surface area measurement techniques were used to investigate properties of the MnO 2 powder.The results showed that the nano MnO 2 with an average diameter in 30～50nm and good dispersity and high catalytic activity for H 2O 2 decomposition,can be synthesized with the two methods.With reduced crystal size of the powder,the infrared absorption peak of Mn O bond was blue shifted and fissioned,one shifted 61 19cm -1 and the other shifted 11 15cm -1 ,and the characteristic vibration bands of adsorption water were also blue shifted.展开更多
文摘Copper(Ⅱ) oxides powder catalysts were prepared by three different methods,thermal decomposition,solid phase reaction and chemical precipitation.The phase,surface structure,morphology,particle size and catalytic activity of the powder for H 2O 2 decomposition were investigated by XRD,SEM,FT IR and the surface area measurement techniques.These studies revealed that high low sequence of catalytic activity of powder prepared by three different methods is opposite from their surface area,and that catalytic activity of the powder is principally related to its surface structure and active compositions.
文摘A highly sensitive fluorescence quenching method for the determination of chromium(VI)based on the system of Cr(VI)OFluorophenylfluorone(OFPF)cetyltrimethylammonium bromide(CTMAB)sodium tartrate(Tartrate)was developed.In a pH 420～480 medium of HAcNaAc,chromium(VI)reacts with OFPF,CTMAB and Tartrate to form a nonfluorescent mixed complex and quenches the fluorescence intensity of OFPF.There is a linear relationship between fluorescence quenching intensity and concentration of chromium(VI)from 0 to 02μg/25ml.The detection limit for Cr(VI)is 01μg/L.The method has been applied to the determination of trace chromium(VI)in water samples with satisfactory results.
文摘Ultrafine Powder CuO was prepared by direct-heating Cu2(OH)2CO3 in differe nt calcination temperatures. XRD, FT-IR, SEM and surface area measurement tech niques were used to investigate the properties of the CuO powder. The results sh ow that the decomposition temperature has remarkably effect on crystallite size, morphology, surface structure, IR behavior and activity of the powder for H2O2 decomposition. The major morphology of the particle is fluffy-sphered in the l ower temperature, which is consists of small sheets of crystallite. With the inc reasing of calcination temperature, crystal of CuO grows up, the fluffy-sphere d particle reduces and catalytic activity decreases. FT-IR patterns revealed t hat the absorption of Cu-O and -OH bond in CuO ultrafine powder were red-s hifted.
文摘The distribution of mitomycin(MIT) for injection in aqueous surfactant two phases(ASTP), consisted of cetyltrimethylammonium bromide(CTAB) and sodium oleate(SO) has been studied by spectrophotometry. The results show that for ASTP system with a certain ratio of CTAB to SO the volume of the upper phase decreased and that of the lower phase increased with increase of MIT added, while the distribution ratio K d and single extraction yield Y of MIT in two phases remained approximately constant.
文摘Nanopowder MnO 2 was prepared with two oxidation reduction methods.XRD,SEM,FT IR and surface area measurement techniques were used to investigate properties of the MnO 2 powder.The results showed that the nano MnO 2 with an average diameter in 30～50nm and good dispersity and high catalytic activity for H 2O 2 decomposition,can be synthesized with the two methods.With reduced crystal size of the powder,the infrared absorption peak of Mn O bond was blue shifted and fissioned,one shifted 61 19cm -1 and the other shifted 11 15cm -1 ,and the characteristic vibration bands of adsorption water were also blue shifted.
