Monoglyceride(MAG)is a widely used nonionic surfactant.In this work,an economic and green solid superbase HND-63 was utilized to synthesize monoglyceride,and the independent variables were examined to achieve the high...Monoglyceride(MAG)is a widely used nonionic surfactant.In this work,an economic and green solid superbase HND-63 was utilized to synthesize monoglyceride,and the independent variables were examined to achieve the highest MAG content.HND-63 was characterized in order to explore the potential reasons for its high MAG selectivity.At the same time,the catalytic mechanism of HND-63 in glycerolysis reaction was also focused on in this paper.A maximum of 72.50%MAG content was obtained under the optimal reaction parameters(reaction temperature of 110.5◦C,reaction time of 209 min,molar ratio of glycerol to oil of 9.2:1,and catalyst dosage of 10.1%).The activation energy Ea and the pre-exponential factor A of the reaction were 61.37 kJ/mol and 6.33×10^(6) mol·L^(-1)·min^(-1),respectively.The basic site of HND-63 is O^(2-),which is loaded on molecular sieve analogs in the form of Na_(2)O,thus providing great convenience for recovery.The findings offer a novel solid superbase that could be potentially applied to glycerolysis reactions,providing the foundation for further development of plantbased surfactants.展开更多
This work gives a comparison on the microstructural characteristics,textural discrepancies,and twinning behaviors of lamellar and equiaxed nearβ-Ti alloys during multi-pass cross rolling with a rolling reduction of 2...This work gives a comparison on the microstructural characteristics,textural discrepancies,and twinning behaviors of lamellar and equiaxed nearβ-Ti alloys during multi-pass cross rolling with a rolling reduction of 20%,50%and 80%.The results showed that the restoration mechanism of the alloy inβphase is strongly dependent on theαmorphologies,and in comparison,strain path has weaker influences on the grain refinement of theβmatrix.Therefore,the texture intensities of bothαandβphases were weakened owing to the dynamic recrystallization(DRX)of the two phases in the equiaxed microstructure.While,with regard to the lamellar microstructure,dynamic recovery(DRV)of theβphase predominated,forming elongatedβsubgrains.Besides,theαandβmatrix in lamellar microstructures obeyed the Burgers orientation relationship,which was gradually broken down until the final reduction.Lastly,the{1101}twinning exhibits a strong size effect.With the continuous DRX ofαphases,theα-twinning is suppressed owing to progressive grain refinement.The activation ofβ-twinning,namely{332}?113?and{112}?111?,in nearβ-Ti alloys is heavily dependent on the deficientβ-stabilizing elements and the local stress concentration.These findings provide an effective way to obtain ultra-fine grain microstructures of this alloy.展开更多
Chlorophyll has been demonstrated to negatively impact the quality and shelf life of rapeseed oils.In this work,graphene materials for chlorophyll removal from rapeseed oil were explored.It exhibited that thermally re...Chlorophyll has been demonstrated to negatively impact the quality and shelf life of rapeseed oils.In this work,graphene materials for chlorophyll removal from rapeseed oil were explored.It exhibited that thermally reduced graphene oxide(TRGO)was the most effective of all the materials.91.7% of chlorophyll can be removed by TRGO while 99.9% of tocopherol,98.5% of phytosterol,and 85.9% of polyphenol are retained in the oil under the optimized conditions of TRGO loading of 0.5 wt%,30℃ and 10 min.Moreover,82.5% of the initial activity of TRGO can be remained after 5 cycles of use.The structure and surface properties of TRGO and the results of kinetic,thermodynamic,and isothermal studies revealed that the chlorophyll adsorption by TRGO was a spontaneous and endothermic process,which was consistent with the pseudo-second-order kinetic model and with the Freundlich and Temkin models.The mesoporous structure and surface-active sites such as C=C,C=O and C-O groups were proposed as responsible for the excellent performance of TRGO.This work may provide possibilities for the application of novel materials in edible oil bleaching.展开更多
基金financially sponsored by Natural Science Foundation of Henan(252300421033).
文摘Monoglyceride(MAG)is a widely used nonionic surfactant.In this work,an economic and green solid superbase HND-63 was utilized to synthesize monoglyceride,and the independent variables were examined to achieve the highest MAG content.HND-63 was characterized in order to explore the potential reasons for its high MAG selectivity.At the same time,the catalytic mechanism of HND-63 in glycerolysis reaction was also focused on in this paper.A maximum of 72.50%MAG content was obtained under the optimal reaction parameters(reaction temperature of 110.5◦C,reaction time of 209 min,molar ratio of glycerol to oil of 9.2:1,and catalyst dosage of 10.1%).The activation energy Ea and the pre-exponential factor A of the reaction were 61.37 kJ/mol and 6.33×10^(6) mol·L^(-1)·min^(-1),respectively.The basic site of HND-63 is O^(2-),which is loaded on molecular sieve analogs in the form of Na_(2)O,thus providing great convenience for recovery.The findings offer a novel solid superbase that could be potentially applied to glycerolysis reactions,providing the foundation for further development of plantbased surfactants.
基金financial supports from the National Natural Science Foundation of China(No.51871242)Scientific and technological innovation projects of Hunan Province,China(No.2017GK2292)the National Key R&D Program of China(2018YFB0704100)。
文摘This work gives a comparison on the microstructural characteristics,textural discrepancies,and twinning behaviors of lamellar and equiaxed nearβ-Ti alloys during multi-pass cross rolling with a rolling reduction of 20%,50%and 80%.The results showed that the restoration mechanism of the alloy inβphase is strongly dependent on theαmorphologies,and in comparison,strain path has weaker influences on the grain refinement of theβmatrix.Therefore,the texture intensities of bothαandβphases were weakened owing to the dynamic recrystallization(DRX)of the two phases in the equiaxed microstructure.While,with regard to the lamellar microstructure,dynamic recovery(DRV)of theβphase predominated,forming elongatedβsubgrains.Besides,theαandβmatrix in lamellar microstructures obeyed the Burgers orientation relationship,which was gradually broken down until the final reduction.Lastly,the{1101}twinning exhibits a strong size effect.With the continuous DRX ofαphases,theα-twinning is suppressed owing to progressive grain refinement.The activation ofβ-twinning,namely{332}?113?and{112}?111?,in nearβ-Ti alloys is heavily dependent on the deficientβ-stabilizing elements and the local stress concentration.These findings provide an effective way to obtain ultra-fine grain microstructures of this alloy.
基金supported by the National Key R&D Program of China(2023YFD2100400 and 2021YFD2100300)the Key R&D Program of Shandong Province(2023TZXD010)+1 种基金Key Research and Development Program of Shandong Province(2021CXGC010808)the Fundamental Research Funds for the Central Universities(JUSRP123045).
文摘Chlorophyll has been demonstrated to negatively impact the quality and shelf life of rapeseed oils.In this work,graphene materials for chlorophyll removal from rapeseed oil were explored.It exhibited that thermally reduced graphene oxide(TRGO)was the most effective of all the materials.91.7% of chlorophyll can be removed by TRGO while 99.9% of tocopherol,98.5% of phytosterol,and 85.9% of polyphenol are retained in the oil under the optimized conditions of TRGO loading of 0.5 wt%,30℃ and 10 min.Moreover,82.5% of the initial activity of TRGO can be remained after 5 cycles of use.The structure and surface properties of TRGO and the results of kinetic,thermodynamic,and isothermal studies revealed that the chlorophyll adsorption by TRGO was a spontaneous and endothermic process,which was consistent with the pseudo-second-order kinetic model and with the Freundlich and Temkin models.The mesoporous structure and surface-active sites such as C=C,C=O and C-O groups were proposed as responsible for the excellent performance of TRGO.This work may provide possibilities for the application of novel materials in edible oil bleaching.
