An industrialized technique of preparation for oxidized com starch using oxygen as oxidant was investigated in this paper. The industrialized preparation parameters were optimized as follows： reaction temperature 85-...An industrialized technique of preparation for oxidized com starch using oxygen as oxidant was investigated in this paper. The industrialized preparation parameters were optimized as follows： reaction temperature 85-95 ℃, oxygen flow rate 8-12 L/min, reaction time 210 min, the ratio of starch to water 1：5, 3.5 wt% of NaOH and 0.1 wt% of catalyst. The experimental results show that the concentration of hydrolysate-oxidaton product is 16-18 wt%. The powdered products were gained through dehydrated and powdered process using quadruple-effect evaporator, spray drying tower and guide shell mixer. The composting test indicates that the degradability of the oxidized corn starch can reach 76.4%. The complexation capacity of calcium ions reaches 108.5 mg per gram oxidized starch, and the detergency ratio （P） reaches 1.30 as builder.展开更多
Through analyzing the components of convertible bond＇s value, this paper studied the determinants of premiums of Chinese CBs. According to this research, the premiums in fixed period are significantly higher than tha...Through analyzing the components of convertible bond＇s value, this paper studied the determinants of premiums of Chinese CBs. According to this research, the premiums in fixed period are significantly higher than that in conversion period due to legal constraints. The premiums in conversion period are negatively related to conversion value, risk-free interest rate, whether the issuing firm has right to advance repayment, whether in selling back period, and additional selling back price, and are positively related to exercise price, risk, and redemption price.展开更多
Na-A zeolite was successfully synthesized via the alkaline fusion method with oil shale ash as the raw material. The adsorption capacity of it was tested by removing Cu2＋, Ni2＋, Pb2＋ and Cd2＋ from aqueous solution...Na-A zeolite was successfully synthesized via the alkaline fusion method with oil shale ash as the raw material. The adsorption capacity of it was tested by removing Cu2＋, Ni2＋, Pb2＋ and Cd2＋ from aqueous solutions. The results reveal the maximum adsorption capacity of adsorbent for Pb2＋, Cu2＋, Cd2＋ and Ni2＋ were 224.72, 156.74, 118.34 and 53.02 mg/g, respectively. The effects of contact time and pH value of solutions on the adsorption effi- ciency of the zeolite were evaluated. Besides, The equilibrium adsorption data and the batch kinetic data were correlated with Langmuir and Freundlich models and the pseudo-first-order and pseudo-second-order models separately. The results show that the Langmuir isotherm and the pseudo-second-order equation were more suitable for the adsorption of Na-A zeolite for the metal ions. In addition, Thermodynamic parameters of the adsorption（the Gibbs free energy, entropy, and enthalpy） were also evaluated and discussed. The results demonstrate that the adsorption process was spontaneous and endothermic under natural conditions and the synthesized zeolite was an effective adsorbent for the removal of metal ions from aqueous solution.展开更多
文摘An industrialized technique of preparation for oxidized com starch using oxygen as oxidant was investigated in this paper. The industrialized preparation parameters were optimized as follows： reaction temperature 85-95 ℃, oxygen flow rate 8-12 L/min, reaction time 210 min, the ratio of starch to water 1：5, 3.5 wt% of NaOH and 0.1 wt% of catalyst. The experimental results show that the concentration of hydrolysate-oxidaton product is 16-18 wt%. The powdered products were gained through dehydrated and powdered process using quadruple-effect evaporator, spray drying tower and guide shell mixer. The composting test indicates that the degradability of the oxidized corn starch can reach 76.4%. The complexation capacity of calcium ions reaches 108.5 mg per gram oxidized starch, and the detergency ratio （P） reaches 1.30 as builder.
文摘Through analyzing the components of convertible bond＇s value, this paper studied the determinants of premiums of Chinese CBs. According to this research, the premiums in fixed period are significantly higher than that in conversion period due to legal constraints. The premiums in conversion period are negatively related to conversion value, risk-free interest rate, whether the issuing firm has right to advance repayment, whether in selling back period, and additional selling back price, and are positively related to exercise price, risk, and redemption price.
文摘Na-A zeolite was successfully synthesized via the alkaline fusion method with oil shale ash as the raw material. The adsorption capacity of it was tested by removing Cu2＋, Ni2＋, Pb2＋ and Cd2＋ from aqueous solutions. The results reveal the maximum adsorption capacity of adsorbent for Pb2＋, Cu2＋, Cd2＋ and Ni2＋ were 224.72, 156.74, 118.34 and 53.02 mg/g, respectively. The effects of contact time and pH value of solutions on the adsorption effi- ciency of the zeolite were evaluated. Besides, The equilibrium adsorption data and the batch kinetic data were correlated with Langmuir and Freundlich models and the pseudo-first-order and pseudo-second-order models separately. The results show that the Langmuir isotherm and the pseudo-second-order equation were more suitable for the adsorption of Na-A zeolite for the metal ions. In addition, Thermodynamic parameters of the adsorption（the Gibbs free energy, entropy, and enthalpy） were also evaluated and discussed. The results demonstrate that the adsorption process was spontaneous and endothermic under natural conditions and the synthesized zeolite was an effective adsorbent for the removal of metal ions from aqueous solution.
