Fresh blood of Tibetan sheep was subjected to protein separation and spray drying, and the effects of drying process on water content, yield and nitrogen soluble index of plasma powder from blood of Tibetan sheep were...Fresh blood of Tibetan sheep was subjected to protein separation and spray drying, and the effects of drying process on water content, yield and nitrogen soluble index of plasma powder from blood of Tibetan sheep were investigated. The results showed that the optimum separation parameters were a centrifugal speed at 6 000 r/min, centrifugal time of 20 min, a mass fraction of dry matter of 20%, an inlet air temperature at 180 ℃ and a feed rate at 400 ml/h, under which the plasma protein was a pale yellow powdery solid, indicating a good separation effect.展开更多
In reversed-phase high performance liquid chromatography （RP-HPLC）, the mobile phase condition for separating eight isoflavones （daidzin, glycitin, genistin, 6＇-o-acetyl daidzin, 6＇-o-malonyl genistin, daidzein, ...In reversed-phase high performance liquid chromatography （RP-HPLC）, the mobile phase condition for separating eight isoflavones （daidzin, glycitin, genistin, 6＇-o-acetyl daidzin, 6＇-o-malonyl genistin, daidzein, glycitein and genistein） was optimized using the HCI （High-Purity Separation Laboratory, Department of Chemical Engineering, Inha University） program software. The optimum composition of mobile phase for the separation of the eight isoflavones was obtained. The elution profiles were calculated by the plate theory based on the equations of retention factor, In k=A＋BF＋CF2, where F was the volume percentage of acetonitrile with 0.1% acetic acid （AA）. The first mobile phase composition was water with 0.1% AA/acetonitrile with 0.1% AA （88%/12%, by volume）, followed at 9min later by the second composition of mobile phase which was step-changed to 85%/15%, at 19rain by the third composition which was step-changed to 73%/27%, at 30min when it was changed to 65%/35% and finally it was maintained in isocratic mode to the end of the run time at 50rain. Although, using step gradient mode to separate the isoflavones, the calculated and experimented data were not achieved very good agreement, we could estimate the closed retention time before experiment. And the agreement between the experimental data and the calculated values was relatively good using isocratic separation for eight isoflavones, but the retention time is very long.展开更多
The bottleneck of strontium compounds preparing from celestite is the promotion of Sr/S isolation efficiency.Low energy consumption and zero release method for isolating Sr/S in preparing Sr(OH)2 process from celestit...The bottleneck of strontium compounds preparing from celestite is the promotion of Sr/S isolation efficiency.Low energy consumption and zero release method for isolating Sr/S in preparing Sr(OH)2 process from celestite in mild condition was described.Sr element remained in precipitation with formation of Sr(OH)2,while S element entered into leachate with formation of Na2SO4.The effects of initial concentration of NaOH,conversion temperature,liquid-to-solid(L/S)ratio and conversion time on Sr/S ratio of samples for celestite conversion were systematically investigated by experiments.The results demonstrated that the efficiency of Sr/S isolation increased with the initial concentration of NaOH,L/S ratio and conversion time,and decreased with conversion temperature.The maximum conversion ratio of Sr(OH)2 was 93.88%under the optimum condition,whose Sr/S ratio of sample could reach to 41.16.It illustrated that better isolation efficiency of celestite could be achieved in alkaline treatment.The results of SEM-EDS analyses demonstrated that the conversion reaction was a dissolution-precipitation process.展开更多
Constructing bismuth oxyhalide solid solutions with a single homogeneous phase have intrigued the research community;however,a deeper understanding of the intrinsic origin for improved bulk-charge separation is still ...Constructing bismuth oxyhalide solid solutions with a single homogeneous phase have intrigued the research community;however,a deeper understanding of the intrinsic origin for improved bulk-charge separation is still unclear.Herein,a series of Bi_(24)O_(31)Cl_(x)Br_(10-x) solid solutions with the same structural characteristics were synthesized by crystal structure regulation.Combining density functional theory calculation,Kelvin probe force microscopy,and zeta potential testing results,an enhanced internal electric field(IEF)intensity between[Bi_(24)O_(31)]and[X]layers was achieved by changing halogen types and ratios.This greatly facilitated bulk-charge separation and transfer efficiency,which is significant for the degradation of phenolic organic pollutants.Owing to the enhanced IEF intensity,the charge carrier density of Bi_(24)O_(31)Cl_(4)Br_(6) was 33.1 and 4.7 times stronger than that of Bi_(24)O_(31)Cl_(10) and Bi_(24)O_(31)Br_(10),respectively.Therefore,Bi24O31Cl4Br6 had an optimal photoactivity for the degradation of bisphenol A,which was 6.21 and 2.71 times higher than those of Bi_(24)O_(31)Cl_(10) and Bi_(24)O_(31)Br_(10),respectively.Thus,this study revealed the intrinsic mechanism of the solid solution strategy for photocatalytic performance enhancement with respect to an IEF.展开更多
An antithrombus enzyme (ATE) was precipitated by (NH4)2SO4 or ethanol from supernatant of Bacillus subtilis culture broth then purified using ion exchange chromatography on CM-sepharose fast flow. The effects of ionic...An antithrombus enzyme (ATE) was precipitated by (NH4)2SO4 or ethanol from supernatant of Bacillus subtilis culture broth then purified using ion exchange chromatography on CM-sepharose fast flow. The effects of ionic strength and pH value on protein adsorption, the gradient elution at different flow rates and step elution were examined respectively. The recovery yield of the optimised process was 74.5% with a purification factor 8.1. The ATE molecular weight was estimated as 30ku by SDS-PAGE. The experimental results showed that the enzyme was stable in the range of pH 7 to pH11, and temperature 25℃ to 37℃.展开更多
基金Supported by"123"Science and Technology Support Program from Science and Technology Department of Qinghai Province(2014-GX-136A)~~
文摘Fresh blood of Tibetan sheep was subjected to protein separation and spray drying, and the effects of drying process on water content, yield and nitrogen soluble index of plasma powder from blood of Tibetan sheep were investigated. The results showed that the optimum separation parameters were a centrifugal speed at 6 000 r/min, centrifugal time of 20 min, a mass fraction of dry matter of 20%, an inlet air temperature at 180 ℃ and a feed rate at 400 ml/h, under which the plasma protein was a pale yellow powdery solid, indicating a good separation effect.
文摘In reversed-phase high performance liquid chromatography （RP-HPLC）, the mobile phase condition for separating eight isoflavones （daidzin, glycitin, genistin, 6＇-o-acetyl daidzin, 6＇-o-malonyl genistin, daidzein, glycitein and genistein） was optimized using the HCI （High-Purity Separation Laboratory, Department of Chemical Engineering, Inha University） program software. The optimum composition of mobile phase for the separation of the eight isoflavones was obtained. The elution profiles were calculated by the plate theory based on the equations of retention factor, In k=A＋BF＋CF2, where F was the volume percentage of acetonitrile with 0.1% acetic acid （AA）. The first mobile phase composition was water with 0.1% AA/acetonitrile with 0.1% AA （88%/12%, by volume）, followed at 9min later by the second composition of mobile phase which was step-changed to 85%/15%, at 19rain by the third composition which was step-changed to 73%/27%, at 30min when it was changed to 65%/35% and finally it was maintained in isocratic mode to the end of the run time at 50rain. Although, using step gradient mode to separate the isoflavones, the calculated and experimented data were not achieved very good agreement, we could estimate the closed retention time before experiment. And the agreement between the experimental data and the calculated values was relatively good using isocratic separation for eight isoflavones, but the retention time is very long.
基金Project(2015-GX-108A)supported by Qinghai Provincial Science and Technology Support Program,China
文摘The bottleneck of strontium compounds preparing from celestite is the promotion of Sr/S isolation efficiency.Low energy consumption and zero release method for isolating Sr/S in preparing Sr(OH)2 process from celestite in mild condition was described.Sr element remained in precipitation with formation of Sr(OH)2,while S element entered into leachate with formation of Na2SO4.The effects of initial concentration of NaOH,conversion temperature,liquid-to-solid(L/S)ratio and conversion time on Sr/S ratio of samples for celestite conversion were systematically investigated by experiments.The results demonstrated that the efficiency of Sr/S isolation increased with the initial concentration of NaOH,L/S ratio and conversion time,and decreased with conversion temperature.The maximum conversion ratio of Sr(OH)2 was 93.88%under the optimum condition,whose Sr/S ratio of sample could reach to 41.16.It illustrated that better isolation efficiency of celestite could be achieved in alkaline treatment.The results of SEM-EDS analyses demonstrated that the conversion reaction was a dissolution-precipitation process.
文摘Constructing bismuth oxyhalide solid solutions with a single homogeneous phase have intrigued the research community;however,a deeper understanding of the intrinsic origin for improved bulk-charge separation is still unclear.Herein,a series of Bi_(24)O_(31)Cl_(x)Br_(10-x) solid solutions with the same structural characteristics were synthesized by crystal structure regulation.Combining density functional theory calculation,Kelvin probe force microscopy,and zeta potential testing results,an enhanced internal electric field(IEF)intensity between[Bi_(24)O_(31)]and[X]layers was achieved by changing halogen types and ratios.This greatly facilitated bulk-charge separation and transfer efficiency,which is significant for the degradation of phenolic organic pollutants.Owing to the enhanced IEF intensity,the charge carrier density of Bi_(24)O_(31)Cl_(4)Br_(6) was 33.1 and 4.7 times stronger than that of Bi_(24)O_(31)Cl_(10) and Bi_(24)O_(31)Br_(10),respectively.Therefore,Bi24O31Cl4Br6 had an optimal photoactivity for the degradation of bisphenol A,which was 6.21 and 2.71 times higher than those of Bi_(24)O_(31)Cl_(10) and Bi_(24)O_(31)Br_(10),respectively.Thus,this study revealed the intrinsic mechanism of the solid solution strategy for photocatalytic performance enhancement with respect to an IEF.
文摘An antithrombus enzyme (ATE) was precipitated by (NH4)2SO4 or ethanol from supernatant of Bacillus subtilis culture broth then purified using ion exchange chromatography on CM-sepharose fast flow. The effects of ionic strength and pH value on protein adsorption, the gradient elution at different flow rates and step elution were examined respectively. The recovery yield of the optimised process was 74.5% with a purification factor 8.1. The ATE molecular weight was estimated as 30ku by SDS-PAGE. The experimental results showed that the enzyme was stable in the range of pH 7 to pH11, and temperature 25℃ to 37℃.
