利用Aspen Plus模拟软件,建立了分离丙酮-乙醇-水物系的隔壁塔工艺流程。在保证丙酮产品纯度不低于99.2%的前提下,使用响应面法分析了隔壁塔的结构参数对能耗的影响,拟合出塔结构参数与再沸器热负荷的二次方程,对隔壁塔的结构参数进行...利用Aspen Plus模拟软件,建立了分离丙酮-乙醇-水物系的隔壁塔工艺流程。在保证丙酮产品纯度不低于99.2%的前提下,使用响应面法分析了隔壁塔的结构参数对能耗的影响,拟合出塔结构参数与再沸器热负荷的二次方程,对隔壁塔的结构参数进行了优化。优化结果为:预分离段、公共精馏段、公共提馏段和侧线采出段的理论塔板数分别为22,20,19,18;预分离段的进料位置为第16塔板,公共提馏段的再沸器热负荷为405.63 k W。验证结果显示,优化结果与模拟结果的相对误差为0.65%,说明流程模拟与响应面法相结合用于隔壁塔结构参数的优化可行。与传统工艺相比,隔壁塔分离工艺的设备费用降低26.86%、年度总费用降低41.10%。展开更多
New initiator systems for the ring-opening polymerization of 1,4-dioxan-2-one (PDO), AlEt 3-M(AcAc) n-H 2O, where M=Nd, La, Zn, Fe, Co and Ni, were used to initiate the ring-opening polymerization of PDO in bulk, and ...New initiator systems for the ring-opening polymerization of 1,4-dioxan-2-one (PDO), AlEt 3-M(AcAc) n-H 2O, where M=Nd, La, Zn, Fe, Co and Ni, were used to initiate the ring-opening polymerization of PDO in bulk, and to synthesize poly(1,4-dioxan-2-one)(PPDO) with high molecular weights within very short reaction time. A high conversion of monomer can be reached. Of all those initiator systems, AlEt 3-Nd(AcAc) 3-H 2O is the best one. The effects of n(Al)∶n(Nd) and n(H 2O)∶n(Al) on the polymerization of PDO were investigated. It was found that n(AlEt 3)∶ n[Nd(AcAc) 3]∶n(H 2O)=8∶1∶4 could obtain the best initiating effects. PPDO with a viscosity-average molecular weight of 3.1×105 can be obtained when n(PDO)∶n[AlEt 3-Nd(AcAc) 3-H 2O] is 2 000, the reaction temperature 80 ℃, and the reaction time 24 h. Meanwhile, a high conversion of 94.7% can be reached.展开更多
In order to investigate the effect of magnetic field on the liquid-liquid extraction, the extraction in the acetone-water-trichloroethane system was studied under magnetic field with different magnetic induction inten...In order to investigate the effect of magnetic field on the liquid-liquid extraction, the extraction in the acetone-water-trichloroethane system was studied under magnetic field with different magnetic induction intensity.The results showed that the effect of magnetic field was positive in the extraction process, and the partition coeffi-cient and the yield of acetone increased-with the increasing magnetic induction intensity by 5.16%-8.35% and 1.85%-5.70% respectively. The effect of magnetic field on the extraction was intensified when the temperature became, higher. The experimental data of the partition coefficient of acetone were correlated by the method of least square in terms of a power-law correlation.展开更多
Pervaporation has attracted considerable interest owing to its potential application in recovering biobutanol from biomass acetone-butanol-ethanol (ABE) fermentation broth. In this study, butanol was recovered from it...Pervaporation has attracted considerable interest owing to its potential application in recovering biobutanol from biomass acetone-butanol-ethanol (ABE) fermentation broth. In this study, butanol was recovered from its aqueous solution using a polydimethylsiloxane (PDMS)/ceramic composite pervaporation membrane. The effects of operating temperature, feed concentration, feed flow rate and operating time on the membrane pervaporation performance were investigated. It was found that with the increase of temperature or butanol concentration in the feed, the total flux through the membrane increased while the separation factor decreased slightly. As the feed flow rate increased, the total flux increased gradually while the separation factor changed little. At 40°C and 1% (by mass) butanol in the feed, the total flux and separation factor of the membrane reached 457.4 g·m?2·h?1 and 26.1, respectively. The membrane with high flux is suitable for recovering butanol from ABE fermentation broth.展开更多
Inexpensive and efficient Cu(Ⅰ) catalysis is reported for the synthesis of α-hydroxy ketones from propargylic alcohols, CO2, and water via tandem carboxylative cyclization and nucleophilic addition reaction. Notably...Inexpensive and efficient Cu(Ⅰ) catalysis is reported for the synthesis of α-hydroxy ketones from propargylic alcohols, CO2, and water via tandem carboxylative cyclization and nucleophilic addition reaction. Notably, hydration of propargylic alcohols can be carried out smoothly under atmospheric CO2 pressure, generating a series of α-hydroxy ketones efficiently and selectively. This strategy shows great potential for the preparation of valuable α-hydroxy ketones by using CO2 as a crucial cocatalyst under mild conditions.展开更多
This report describes a new three‐component strategy for the regioselective synthesis of a series of tri‐substituted pyridazines via a 1,4‐diazabicyclo[2.2.2]octane （DABCO）‐catalyzed condensation of propiophenon...This report describes a new three‐component strategy for the regioselective synthesis of a series of tri‐substituted pyridazines via a 1,4‐diazabicyclo[2.2.2]octane （DABCO）‐catalyzed condensation of propiophenones, arylglyoxalmonohydrates and hydrazine hydrate in water. This method provides a green and convenient one‐pot route toward a diverse set of 3,6‐diaryl‐4‐methylpyridazines bearing various aryl substituents. This procedure is highly regioselective, operationally simple, uses water as a safe, environmentally friendly solvent, and DABCO as a green base‐organocatalyst, and affords good to excellent yields of products.展开更多
The responses of photosynthesis of phosphoenopyruvate carboxylase (PEPC), pyrurate dikinase (PPDK), NADP-malic enzyme (NADP-ME) and PPDK+PEPC transgenic rice (Oryza saltiva L.) plant to light, temperature, CO 2 and t...The responses of photosynthesis of phosphoenopyruvate carboxylase (PEPC), pyrurate dikinase (PPDK), NADP-malic enzyme (NADP-ME) and PPDK+PEPC transgenic rice (Oryza saltiva L.) plant to light, temperature, CO 2 and the characteristics of chlorophyll fluorescence under photoinhibition conditions were studied. The results were as follows: 1. The light-saturated photosynthetic rates of transgenic rice plants were higher than that of wild type, in which the light-saturated point of PEPC and PPDK+PEPC transgenic rice plants was 200 μmol·m -2·s -1 higher than that of untransformed rice and the light-saturated photosynthetic rates were 51.6% and 58.5% respectively. The carboxylation efficiency of PEPC transgenic rice plant increased by 49.3% and the CO 2 compensation point decreased by 26.2% than that of untransformed rice. Under high temperature (35 ℃), the photosynthetic rate of PEPC transgenic rice plant was higher over 17.5% than that of untransformed rice. 2. On the 8th day after photoinhibition treatment, the PSⅡ photochemical efficiency (F v/F m) and photochemical quenching (qP) of PEPC and PPDK+PEPC transgenic rice plants decreased by about 20%-30% while the non-photochemical quenching (qN) increased by approximately 30%. But F v/F m and qP of untransformed rice decreased by over 50% while qN increased by less than 10%. The result suggested that transgenic rice plants were more tolerant to photoinhibition.展开更多
文摘利用Aspen Plus模拟软件,建立了分离丙酮-乙醇-水物系的隔壁塔工艺流程。在保证丙酮产品纯度不低于99.2%的前提下,使用响应面法分析了隔壁塔的结构参数对能耗的影响,拟合出塔结构参数与再沸器热负荷的二次方程,对隔壁塔的结构参数进行了优化。优化结果为:预分离段、公共精馏段、公共提馏段和侧线采出段的理论塔板数分别为22,20,19,18;预分离段的进料位置为第16塔板,公共提馏段的再沸器热负荷为405.63 k W。验证结果显示,优化结果与模拟结果的相对误差为0.65%,说明流程模拟与响应面法相结合用于隔壁塔结构参数的优化可行。与传统工艺相比,隔壁塔分离工艺的设备费用降低26.86%、年度总费用降低41.10%。
文摘New initiator systems for the ring-opening polymerization of 1,4-dioxan-2-one (PDO), AlEt 3-M(AcAc) n-H 2O, where M=Nd, La, Zn, Fe, Co and Ni, were used to initiate the ring-opening polymerization of PDO in bulk, and to synthesize poly(1,4-dioxan-2-one)(PPDO) with high molecular weights within very short reaction time. A high conversion of monomer can be reached. Of all those initiator systems, AlEt 3-Nd(AcAc) 3-H 2O is the best one. The effects of n(Al)∶n(Nd) and n(H 2O)∶n(Al) on the polymerization of PDO were investigated. It was found that n(AlEt 3)∶ n[Nd(AcAc) 3]∶n(H 2O)=8∶1∶4 could obtain the best initiating effects. PPDO with a viscosity-average molecular weight of 3.1×105 can be obtained when n(PDO)∶n[AlEt 3-Nd(AcAc) 3-H 2O] is 2 000, the reaction temperature 80 ℃, and the reaction time 24 h. Meanwhile, a high conversion of 94.7% can be reached.
基金Supported by the Program on Technological Development Plan of Tianjin (No.033180611).
文摘In order to investigate the effect of magnetic field on the liquid-liquid extraction, the extraction in the acetone-water-trichloroethane system was studied under magnetic field with different magnetic induction intensity.The results showed that the effect of magnetic field was positive in the extraction process, and the partition coeffi-cient and the yield of acetone increased-with the increasing magnetic induction intensity by 5.16%-8.35% and 1.85%-5.70% respectively. The effect of magnetic field on the extraction was intensified when the temperature became, higher. The experimental data of the partition coefficient of acetone were correlated by the method of least square in terms of a power-law correlation.
基金Supported by the National Basic Research Program of China（2009CB623406） the National Natural Science Foundation of China（20990222）+1 种基金 the Natural Science Foundation of Jiangsu Province（SBK200930313） the“Six Kinds of Important Talents”Program of Jiangsu Province（2007007）
文摘Pervaporation has attracted considerable interest owing to its potential application in recovering biobutanol from biomass acetone-butanol-ethanol (ABE) fermentation broth. In this study, butanol was recovered from its aqueous solution using a polydimethylsiloxane (PDMS)/ceramic composite pervaporation membrane. The effects of operating temperature, feed concentration, feed flow rate and operating time on the membrane pervaporation performance were investigated. It was found that with the increase of temperature or butanol concentration in the feed, the total flux through the membrane increased while the separation factor decreased slightly. As the feed flow rate increased, the total flux increased gradually while the separation factor changed little. At 40°C and 1% (by mass) butanol in the feed, the total flux and separation factor of the membrane reached 457.4 g·m?2·h?1 and 26.1, respectively. The membrane with high flux is suitable for recovering butanol from ABE fermentation broth.
基金supported by National Natural Science Foundation of China(21672119)China Postdoctoral Science Foundation(2018M641624)~~
文摘Inexpensive and efficient Cu(Ⅰ) catalysis is reported for the synthesis of α-hydroxy ketones from propargylic alcohols, CO2, and water via tandem carboxylative cyclization and nucleophilic addition reaction. Notably, hydration of propargylic alcohols can be carried out smoothly under atmospheric CO2 pressure, generating a series of α-hydroxy ketones efficiently and selectively. This strategy shows great potential for the preparation of valuable α-hydroxy ketones by using CO2 as a crucial cocatalyst under mild conditions.
基金supported by the Research Council of Payame Noor University
文摘This report describes a new three‐component strategy for the regioselective synthesis of a series of tri‐substituted pyridazines via a 1,4‐diazabicyclo[2.2.2]octane （DABCO）‐catalyzed condensation of propiophenones, arylglyoxalmonohydrates and hydrazine hydrate in water. This method provides a green and convenient one‐pot route toward a diverse set of 3,6‐diaryl‐4‐methylpyridazines bearing various aryl substituents. This procedure is highly regioselective, operationally simple, uses water as a safe, environmentally friendly solvent, and DABCO as a green base‐organocatalyst, and affords good to excellent yields of products.
文摘The responses of photosynthesis of phosphoenopyruvate carboxylase (PEPC), pyrurate dikinase (PPDK), NADP-malic enzyme (NADP-ME) and PPDK+PEPC transgenic rice (Oryza saltiva L.) plant to light, temperature, CO 2 and the characteristics of chlorophyll fluorescence under photoinhibition conditions were studied. The results were as follows: 1. The light-saturated photosynthetic rates of transgenic rice plants were higher than that of wild type, in which the light-saturated point of PEPC and PPDK+PEPC transgenic rice plants was 200 μmol·m -2·s -1 higher than that of untransformed rice and the light-saturated photosynthetic rates were 51.6% and 58.5% respectively. The carboxylation efficiency of PEPC transgenic rice plant increased by 49.3% and the CO 2 compensation point decreased by 26.2% than that of untransformed rice. Under high temperature (35 ℃), the photosynthetic rate of PEPC transgenic rice plant was higher over 17.5% than that of untransformed rice. 2. On the 8th day after photoinhibition treatment, the PSⅡ photochemical efficiency (F v/F m) and photochemical quenching (qP) of PEPC and PPDK+PEPC transgenic rice plants decreased by about 20%-30% while the non-photochemical quenching (qN) increased by approximately 30%. But F v/F m and qP of untransformed rice decreased by over 50% while qN increased by less than 10%. The result suggested that transgenic rice plants were more tolerant to photoinhibition.
