The supercritical carbon dioxide extraction was applied to obtain essential oil from Pogostemon cablin in this work.Effect of extraction parameters including temperature,pressure,extraction time and particle size on e...The supercritical carbon dioxide extraction was applied to obtain essential oil from Pogostemon cablin in this work.Effect of extraction parameters including temperature,pressure,extraction time and particle size on extraction yield was investigated,and the response surface methodology with a Box–Behnken Design was used to achieve the optimized extraction conditions.The maximum yield of essential oil was 2.4356%under the conditions of extraction temperature 47°C,pressure 24.5 MPa and extraction time 119 min.Moreover,based on the Brunauer–Emmett–Teller theory of adsorption,a mathematical modeling was performed to correlate the measured data.The model shows a function relationship between extraction yield and time by a simple equation with three significantly adjustable parameters.These model parameters have been optimized through simulated annealing algorithm.The predicted data from the mathematical model show a good agreement with the experimental data of the different extraction parameters.展开更多
In this work, liquid–liquid equilibria(LLE) data for the ternary system methyl tert-butyl ketone(MTBK)+ o, m,p-benzenediol + water were investigated at 333.2 K, 343.2 K and 353.2 K under 101.3 kPa. The performance of...In this work, liquid–liquid equilibria(LLE) data for the ternary system methyl tert-butyl ketone(MTBK)+ o, m,p-benzenediol + water were investigated at 333.2 K, 343.2 K and 353.2 K under 101.3 kPa. The performance of MTBK to extract o, m, p-benzenediol from wastewaters was estimated by partition coefficients and separation factors. The Hand and Bachman equations were both applied to check the reliability of the experimental LLE data. Furthermore, the Non-Random Two-Liquid(NRTL) and Universal Quasi Chemical(UNIQUAC) models were applied to correlate the measured LLE data. The results showed a good agreement with the determined ternary LLE data with the root-mean-square error(RMSE) values below 0.71%. MTBK was proved to be a promising extracting agent in extracting benzenediols from effluents.展开更多
The effects of NaCl, KCl and Na_2SO_4 on the liquid–liquid equilibrium(LLE) data for the ternary system, water+ phenol + methyl isobutyl ketone, were determined at 0.101 MPa and 333.15 K and 343.15 K.The nonrandom tw...The effects of NaCl, KCl and Na_2SO_4 on the liquid–liquid equilibrium(LLE) data for the ternary system, water+ phenol + methyl isobutyl ketone, were determined at 0.101 MPa and 333.15 K and 343.15 K.The nonrandom two-liquid(NRTL) model was used to correlate the experimental data and to yield corresponding binary interaction parameters for these salt containing systems.The Hand and Othmer–Tobias equations were used to confirm the dependability of the determined LLE data in this work.Distribution coefficient and selectivity were used to evaluate the extraction performance of methyl isobutyl ketone with the existence of salt.The magnitude of salt effect on the water + phenol + methyl isobutyl ketone(MIBK) system is in the following order: Na_2SO_4>NaCl>KCl.展开更多
Collapse is a common geomorphic process in karst areas,especially on the Yunnan-Guizhou Plateau,which has a tectonic background of integral uplift.The frequent occurrence of collapse processes in karst underground cav...Collapse is a common geomorphic process in karst areas,especially on the Yunnan-Guizhou Plateau,which has a tectonic background of integral uplift.The frequent occurrence of collapse processes in karst underground caves and canyons indicates that collapses play an important role in the formation of canyons.Through an analysis of the morphology of a semicircular cliff in the Huajiang Grand Canyon and an investigation of sediments at the bottom of the cliff,a large-scale collapse event was found to have occurred.U-series dating of secondary calcium carbonate cement in the collapse breccias indicates that collapse processes occurred approximately 200 ka.According to the geomorphological evolution of the Huajiang Grand Canyon,the following geomorphic evolutionary process is proposed:underground river-cave hall-collapse of a tiankeng-tiankeng degradation-canyon formation.These findings also show that the dating of collapsed breccia cement can be effectively used to determine the development times of karst canyons and the formation ages of tiankengs.展开更多
Kadsura coccinea(Lem.)is a woody wine plant with a peculiar fruit enriched in important health-promoting compounds.The non-editable part of the fruit,i.e.,the seed and peel,represents more than 60%of the fruit and is ...Kadsura coccinea(Lem.)is a woody wine plant with a peculiar fruit enriched in important health-promoting compounds.The non-editable part of the fruit,i.e.,the seed and peel,represents more than 60%of the fruit and is considered a biowaste.This significantly restricts the development of the K.coccinea fruit industry.Clarifying the metabolic components of the different fruit parts can help to improve the utilization rate and valorization of K.coccinea.Herein,we evaluated K.coccinea fruit peel,pulp,and seed using widely-targeted metabolomics and quantified a set of 736 bioactive compounds from 11 major metabolite classes.The most prominent metabolite classes included lipids,amino acids,flavonoids,and lignans.Furthermore,our results emphasized a significant accumulation of flavonoids in pulp tissues,while alkaloids and lignans were abundant in peel and seed tissues,respectively.A total of 183 metabolites were differentially accumulated among the three tissues.Procyanidin C2,rutinoside,2-hydroxyoleanolic acid,5-hydroxymethyluracil,nootkatol,isoquercitrin,isohyperoside,quercetin-7-O-glucoside,hyperin,and rutin showed elevated accumulation in the peel.In the seed,kadsuralignan G,kadcoccilactone A,kadsuralignan H,lysoPE 20:5,iso-schisandrin ethyl alcohol,and kadangustin were significantly enriched.Our results highlight the diverse metabolome composition of K.coccinea fruit parts,which can be further exploited for its valorization in various industries.展开更多
文摘The supercritical carbon dioxide extraction was applied to obtain essential oil from Pogostemon cablin in this work.Effect of extraction parameters including temperature,pressure,extraction time and particle size on extraction yield was investigated,and the response surface methodology with a Box–Behnken Design was used to achieve the optimized extraction conditions.The maximum yield of essential oil was 2.4356%under the conditions of extraction temperature 47°C,pressure 24.5 MPa and extraction time 119 min.Moreover,based on the Brunauer–Emmett–Teller theory of adsorption,a mathematical modeling was performed to correlate the measured data.The model shows a function relationship between extraction yield and time by a simple equation with three significantly adjustable parameters.These model parameters have been optimized through simulated annealing algorithm.The predicted data from the mathematical model show a good agreement with the experimental data of the different extraction parameters.
基金Supported by the State Key Laboratory of Pulp and Paper Engineering in China(201703,201708)
文摘In this work, liquid–liquid equilibria(LLE) data for the ternary system methyl tert-butyl ketone(MTBK)+ o, m,p-benzenediol + water were investigated at 333.2 K, 343.2 K and 353.2 K under 101.3 kPa. The performance of MTBK to extract o, m, p-benzenediol from wastewaters was estimated by partition coefficients and separation factors. The Hand and Bachman equations were both applied to check the reliability of the experimental LLE data. Furthermore, the Non-Random Two-Liquid(NRTL) and Universal Quasi Chemical(UNIQUAC) models were applied to correlate the measured LLE data. The results showed a good agreement with the determined ternary LLE data with the root-mean-square error(RMSE) values below 0.71%. MTBK was proved to be a promising extracting agent in extracting benzenediols from effluents.
基金Supported by the National Natural Science Foundation of China(21506066)State Key Laboratory of Pulp and Paper Engineering(201708)+2 种基金the Guangdong Natural Science Foundation(2014A030310260)the Fundamental Research Funds for the Central Universities SCUT(2017ZD069)the Guangzhou Technology Project(201804010219)
文摘The effects of NaCl, KCl and Na_2SO_4 on the liquid–liquid equilibrium(LLE) data for the ternary system, water+ phenol + methyl isobutyl ketone, were determined at 0.101 MPa and 333.15 K and 343.15 K.The nonrandom two-liquid(NRTL) model was used to correlate the experimental data and to yield corresponding binary interaction parameters for these salt containing systems.The Hand and Othmer–Tobias equations were used to confirm the dependability of the determined LLE data in this work.Distribution coefficient and selectivity were used to evaluate the extraction performance of methyl isobutyl ketone with the existence of salt.The magnitude of salt effect on the water + phenol + methyl isobutyl ketone(MIBK) system is in the following order: Na_2SO_4>NaCl>KCl.
基金funded by the National Natural Science Foundation of China(Grant Nos:42061001,41501006)The Science and Technology Foundation of Guizhou Province(Grant Nos:Qianke Jichu-ZK[2021]190)Natural science research funding project of Guizhou Provincial Department of Education(Grant No.:Qian Jiao KY[2021]036).
文摘Collapse is a common geomorphic process in karst areas,especially on the Yunnan-Guizhou Plateau,which has a tectonic background of integral uplift.The frequent occurrence of collapse processes in karst underground caves and canyons indicates that collapses play an important role in the formation of canyons.Through an analysis of the morphology of a semicircular cliff in the Huajiang Grand Canyon and an investigation of sediments at the bottom of the cliff,a large-scale collapse event was found to have occurred.U-series dating of secondary calcium carbonate cement in the collapse breccias indicates that collapse processes occurred approximately 200 ka.According to the geomorphological evolution of the Huajiang Grand Canyon,the following geomorphic evolutionary process is proposed:underground river-cave hall-collapse of a tiankeng-tiankeng degradation-canyon formation.These findings also show that the dating of collapsed breccia cement can be effectively used to determine the development times of karst canyons and the formation ages of tiankengs.
文摘Kadsura coccinea(Lem.)is a woody wine plant with a peculiar fruit enriched in important health-promoting compounds.The non-editable part of the fruit,i.e.,the seed and peel,represents more than 60%of the fruit and is considered a biowaste.This significantly restricts the development of the K.coccinea fruit industry.Clarifying the metabolic components of the different fruit parts can help to improve the utilization rate and valorization of K.coccinea.Herein,we evaluated K.coccinea fruit peel,pulp,and seed using widely-targeted metabolomics and quantified a set of 736 bioactive compounds from 11 major metabolite classes.The most prominent metabolite classes included lipids,amino acids,flavonoids,and lignans.Furthermore,our results emphasized a significant accumulation of flavonoids in pulp tissues,while alkaloids and lignans were abundant in peel and seed tissues,respectively.A total of 183 metabolites were differentially accumulated among the three tissues.Procyanidin C2,rutinoside,2-hydroxyoleanolic acid,5-hydroxymethyluracil,nootkatol,isoquercitrin,isohyperoside,quercetin-7-O-glucoside,hyperin,and rutin showed elevated accumulation in the peel.In the seed,kadsuralignan G,kadcoccilactone A,kadsuralignan H,lysoPE 20:5,iso-schisandrin ethyl alcohol,and kadangustin were significantly enriched.Our results highlight the diverse metabolome composition of K.coccinea fruit parts,which can be further exploited for its valorization in various industries.
