The kinetics of simultaneous transesterification and esterification with a carbon-based solid acid catalyst was studied.Two solid acid catalysts were prepared by the sulfonation of carbonized vegetable oil asphalt and...The kinetics of simultaneous transesterification and esterification with a carbon-based solid acid catalyst was studied.Two solid acid catalysts were prepared by the sulfonation of carbonized vegetable oil asphalt and petroleum asphalt.These catalysts were characterized on the basis of elemental analysis,acidity site concentration,the Brunauer-Emmett-Teller（BET）surface area and pore size.The kinetic parameters with the two catalysts were determined,and the reaction system can be described as a pseudo homogeneous catalyzed reaction.All the forward and reverse reactions follow second order kinetics.The calculated concentration values from the kinetic equations are in good agreement with experimental values.展开更多
Performance of simultaneous desulfurization and denitration using the solution of NaClO2 and NaClO as new-style complex absorbent was investigated experimentally in self-designed bench scale bubbling reactor. The effe...Performance of simultaneous desulfurization and denitration using the solution of NaClO2 and NaClO as new-style complex absorbent was investigated experimentally in self-designed bench scale bubbling reactor. The effects of main parameters, such as the concentrations of NaClO2 and of NaClO, solution pH and reaction temperature and so on, on removal efficiencies of SO2 and NOx, were examined, then the optimal conditions were established, in which the molar ratio of NaClO to NaClO2 was 1：1, the reaction temperature was 50℃ and the solution pH was 5.5. The removal efficiencies of SO2 and NO under the optimal conditions were 100% and 89.2%, respectively. The mechanism of simultaneous removal based on complex absorbent was proposed by analyzing the removal products and the electrode potentials of related species, namely SO2 and NO are oxi- dized by chlorite anion, hypochlorite, chlorine dioxide and chlorine contained in complex absorbent. In thermodynamic aspect, simultaneous desulfurization and denitration reactions in liquid phase can happen spontaneously and completely, and are all exothermic reactions. It was confirmed by kinetics that for simultaneous desulfurization and denitration, the reaction order and average activation energy of SO2 were 1 and 21.6 kJ·mol^-1, respectively, and those of NO were 1 and 8.2 kJ·mol^-1, respectively.展开更多
目的分析8月龄儿童麻腮风联合减毒活疫苗(Measles,mumps and rubella combined attenuated live vaccine,MMR)与乙型脑炎减毒活疫苗(Japanese encephalitis attenuated live vaccine,JEV-L)同时接种的不良反应。方法通过山东省免疫规划...目的分析8月龄儿童麻腮风联合减毒活疫苗(Measles,mumps and rubella combined attenuated live vaccine,MMR)与乙型脑炎减毒活疫苗(Japanese encephalitis attenuated live vaccine,JEV-L)同时接种的不良反应。方法通过山东省免疫规划信息系统和中国疑似预防接种异常反应监测系统收集山东省2020年出生且满8月龄儿童MMR和JEV-L同时或单独接种的剂次数和不良反应个案,采用泊松回归模型计算不良反应报告发生率的95%置信区间(Confidence interval,CI)。结果山东省8月龄儿童MMR与JEV-L同时接种、MMR单独接种、JEV-L单独接种一般反应报告发生率(/10万剂)分别为103.90(95%CI:92.01-117.32)、119.49(95%CI:109.40-130.50)、49.29(95%CI:42.85-56.69),异常反应分别为3.20(95%CI:1.60-6.29)、4.11(95%CI:2.56-6.61)、0.50(95%CI:0.13-2.01)。结论8月龄儿童同时接种MMR和JEV-L同时接种或单独接种的不良反应发生率均在预期范围内,同时接种未增加不良反应的发生风险。展开更多
The single phase La2（CO3）3·3.4H2 O was synthesized by hydrothermal method. The thermal decomposition and intermediates and final solid products of La2（CO3）3·3.4H2O from 30 to 1000 °C were characteri...The single phase La2（CO3）3·3.4H2 O was synthesized by hydrothermal method. The thermal decomposition and intermediates and final solid products of La2（CO3）3·3.4H2O from 30 to 1000 °C were characterized by XRD, FTIR and DTA-TG. The kinetics of dehydration of La2（CO3）3·3.4H2O in the temperature range of 30-366 °C was investigated under non-isothermal conditions. Flynn-Wall-Ozawa and Friedman isoconversion methods were used to calculate the activation energy and analyze the reaction steps; multivariate non-linear regression program was applied to determine the most probable mechanism and the kinetic parameters. The results show that the thermal dehydration of La2（CO3）3·3.4H2O is a kind of three-step competitive reaction, and controlled by an n-order initial reaction followed by n-order competitive reaction（FnFnFn model）. The activation energy matching with the most probable model is close to value obtained by Friedman method. The fitting curves match the original TG-DTG curves very well.展开更多
目的分析2015—2019年深圳市疫苗单独接种和同时接种过敏反应的发生情况,明确同时接种的安全性。方法利用2015—2019年深圳市在国家疑似预防接种异常反应(adverse event following immunization,AEFI)监测系统上报的异常反应中过敏反应...目的分析2015—2019年深圳市疫苗单独接种和同时接种过敏反应的发生情况,明确同时接种的安全性。方法利用2015—2019年深圳市在国家疑似预防接种异常反应(adverse event following immunization,AEFI)监测系统上报的异常反应中过敏反应数据,对单独接种和同时接种疫苗发生过敏反应的情况进行对比分析。结果2015—2019年深圳市共报告过敏反应3718例,其中单独接种组为2537例,同时接种组为1181例,两组间性别、接种时年龄、接种前过敏史及患病史、接种途径等方面比较,差异均无统计学意义(χ^(2)=0.889、1.520、2.757、2.064、1.835,均P>0.05)。在接种后接种部位红肿、硬结及异常反应分型方面,两组间差异均无统计学意义(χ^(2)=2.674、1.926、5.621,均P>0.05);在间隔时间、发热症状及转归状态方面,两组间差异均有统计学意义(χ^(2)=40.582、20.701、9.764,均P<0.01),同时接种过敏反应发生在24 h内的占比和出现发热症状的占比均高于单独接种。结论2015—2019年深圳市两种及以上疫苗同时接种不会增加接种部位局部红肿、局部硬结等症状的发生机率,过敏反应的临床分型也与单独接种没有明显差异,但接种24 h内发生过敏反应和伴发热的占比高于单独接种。提示两种或以上疫苗同时接种的安全性较好,但需关注接种24 h内的过敏反应和发热症状。展开更多
A novel high sensihtity, small-volume photothermal intheence detector has beenintroduced for capillap zone electrophoresis separation analysis. The utility of thes sdriulboconstecheque for momtomp chelating reachon of...A novel high sensihtity, small-volume photothermal intheence detector has beenintroduced for capillap zone electrophoresis separation analysis. The utility of thes sdriulboconstecheque for momtomp chelating reachon of light rare earth with tribromoarsenazo has beenreported.展开更多
The present work extends the previous work^[2] on 5-ion system to consider 7-ion system （i.e., Au^47＋ -Au^53＋）. It is found that more highly charged ions, e.g., Au^53＋, Au^54＋ etc., could be able to be neglected...The present work extends the previous work^[2] on 5-ion system to consider 7-ion system （i.e., Au^47＋ -Au^53＋）. It is found that more highly charged ions, e.g., Au^53＋, Au^54＋ etc., could be able to be neglected, however, less highly charged ions, e.g., Au^47＋, Au^46＋ etc., are rather important. Therefore, a new idea to consider 8-ion system, i.e., Au^46＋ - Au^53＋, is under way. As a supplement, we discuss the simultaneous reaction, which would be important in this sort of works.展开更多
In this paper the rotating packed bed, a new type of absorber, which has high mass-transfer characteristic by means of centrifugal field instead of gravity field, is used to study on stimulated flue gas desulfurizatio...In this paper the rotating packed bed, a new type of absorber, which has high mass-transfer characteristic by means of centrifugal field instead of gravity field, is used to study on stimulated flue gas desulfurization. Based on experimental data,a model of mass-transfer and reaction of the sulfur dioxide chemical absorption in the rotating packed bed reactor is proposed according to the film-theory. It can be used to predict the performance of the total absorption rate and the enhancement factor of the sulfur dioxide and oxygen simultaneous absorption in the rotating packed bed reactor.The prediction of the model is consistent with the experimental result varying operating conditions, and the relative error between experimental result and predicted result is below 12%. Some interesting potential projects of simultaneous absorption of sulfur dioxide and oxygen in the rotating packed bed reactor are also discussed.展开更多
Based on the TiO2 photocatalysis mechanism, a new method of simultaneous desulfurization and denitrification from flue gas was proposed. Preparation of TiO2 photocatalyst, design of photocatalysis reactor and influenc...Based on the TiO2 photocatalysis mechanism, a new method of simultaneous desulfurization and denitrification from flue gas was proposed. Preparation of TiO2 photocatalyst, design of photocatalysis reactor and influencing factors for simul- taneous removal of SO2 and NO, and removal mechanism of SO2 and NO were studied. After the optimal values of concentration of O2 in flue gas, the relative humidity of flue gas and the irradiation time in the photocatalysis reactor were used, the efficiencies of removal for SO2 and NO can be achieved above 98% and about 67%, respectively. According to the results of removal products analysis, the re- moval mechanism of SO2 and NO based on TiO2 photocatlysis can be put forward, namely, SO2 was oxidized to SO3 partly, the bulk of NO was oxidized to NO2, and both were removed by resorbing finally.展开更多
文摘The kinetics of simultaneous transesterification and esterification with a carbon-based solid acid catalyst was studied.Two solid acid catalysts were prepared by the sulfonation of carbonized vegetable oil asphalt and petroleum asphalt.These catalysts were characterized on the basis of elemental analysis,acidity site concentration,the Brunauer-Emmett-Teller（BET）surface area and pore size.The kinetic parameters with the two catalysts were determined,and the reaction system can be described as a pseudo homogeneous catalyzed reaction.All the forward and reverse reactions follow second order kinetics.The calculated concentration values from the kinetic equations are in good agreement with experimental values.
文摘Performance of simultaneous desulfurization and denitration using the solution of NaClO2 and NaClO as new-style complex absorbent was investigated experimentally in self-designed bench scale bubbling reactor. The effects of main parameters, such as the concentrations of NaClO2 and of NaClO, solution pH and reaction temperature and so on, on removal efficiencies of SO2 and NOx, were examined, then the optimal conditions were established, in which the molar ratio of NaClO to NaClO2 was 1：1, the reaction temperature was 50℃ and the solution pH was 5.5. The removal efficiencies of SO2 and NO under the optimal conditions were 100% and 89.2%, respectively. The mechanism of simultaneous removal based on complex absorbent was proposed by analyzing the removal products and the electrode potentials of related species, namely SO2 and NO are oxi- dized by chlorite anion, hypochlorite, chlorine dioxide and chlorine contained in complex absorbent. In thermodynamic aspect, simultaneous desulfurization and denitration reactions in liquid phase can happen spontaneously and completely, and are all exothermic reactions. It was confirmed by kinetics that for simultaneous desulfurization and denitration, the reaction order and average activation energy of SO2 were 1 and 21.6 kJ·mol^-1, respectively, and those of NO were 1 and 8.2 kJ·mol^-1, respectively.
文摘目的分析8月龄儿童麻腮风联合减毒活疫苗(Measles,mumps and rubella combined attenuated live vaccine,MMR)与乙型脑炎减毒活疫苗(Japanese encephalitis attenuated live vaccine,JEV-L)同时接种的不良反应。方法通过山东省免疫规划信息系统和中国疑似预防接种异常反应监测系统收集山东省2020年出生且满8月龄儿童MMR和JEV-L同时或单独接种的剂次数和不良反应个案,采用泊松回归模型计算不良反应报告发生率的95%置信区间(Confidence interval,CI)。结果山东省8月龄儿童MMR与JEV-L同时接种、MMR单独接种、JEV-L单独接种一般反应报告发生率(/10万剂)分别为103.90(95%CI:92.01-117.32)、119.49(95%CI:109.40-130.50)、49.29(95%CI:42.85-56.69),异常反应分别为3.20(95%CI:1.60-6.29)、4.11(95%CI:2.56-6.61)、0.50(95%CI:0.13-2.01)。结论8月龄儿童同时接种MMR和JEV-L同时接种或单独接种的不良反应发生率均在预期范围内,同时接种未增加不良反应的发生风险。
基金Project(201011005-5)supported by the National Land and Resources Public Welfare Scientific Research Project of ChinaProject(41030426)supported by the National Natural Science Foundation of China+1 种基金Project(20095122110015)supported by Specialized Research Fund for the Doctoral Program of Higher Education of ChinaProject(2010-32)supported by Scientific Research Foundation of the Education Ministry for Returned Chinese Scholars,China
文摘The single phase La2（CO3）3·3.4H2 O was synthesized by hydrothermal method. The thermal decomposition and intermediates and final solid products of La2（CO3）3·3.4H2O from 30 to 1000 °C were characterized by XRD, FTIR and DTA-TG. The kinetics of dehydration of La2（CO3）3·3.4H2O in the temperature range of 30-366 °C was investigated under non-isothermal conditions. Flynn-Wall-Ozawa and Friedman isoconversion methods were used to calculate the activation energy and analyze the reaction steps; multivariate non-linear regression program was applied to determine the most probable mechanism and the kinetic parameters. The results show that the thermal dehydration of La2（CO3）3·3.4H2O is a kind of three-step competitive reaction, and controlled by an n-order initial reaction followed by n-order competitive reaction（FnFnFn model）. The activation energy matching with the most probable model is close to value obtained by Friedman method. The fitting curves match the original TG-DTG curves very well.
文摘A novel high sensihtity, small-volume photothermal intheence detector has beenintroduced for capillap zone electrophoresis separation analysis. The utility of thes sdriulboconstecheque for momtomp chelating reachon of light rare earth with tribromoarsenazo has beenreported.
基金The project supported by the National Key Laboratory for High Temperature and Density Plasma Physics under Grant No. 514800203055SC0101
文摘The present work extends the previous work^[2] on 5-ion system to consider 7-ion system （i.e., Au^47＋ -Au^53＋）. It is found that more highly charged ions, e.g., Au^53＋, Au^54＋ etc., could be able to be neglected, however, less highly charged ions, e.g., Au^47＋, Au^46＋ etc., are rather important. Therefore, a new idea to consider 8-ion system, i.e., Au^46＋ - Au^53＋, is under way. As a supplement, we discuss the simultaneous reaction, which would be important in this sort of works.
文摘In this paper the rotating packed bed, a new type of absorber, which has high mass-transfer characteristic by means of centrifugal field instead of gravity field, is used to study on stimulated flue gas desulfurization. Based on experimental data,a model of mass-transfer and reaction of the sulfur dioxide chemical absorption in the rotating packed bed reactor is proposed according to the film-theory. It can be used to predict the performance of the total absorption rate and the enhancement factor of the sulfur dioxide and oxygen simultaneous absorption in the rotating packed bed reactor.The prediction of the model is consistent with the experimental result varying operating conditions, and the relative error between experimental result and predicted result is below 12%. Some interesting potential projects of simultaneous absorption of sulfur dioxide and oxygen in the rotating packed bed reactor are also discussed.
文摘Based on the TiO2 photocatalysis mechanism, a new method of simultaneous desulfurization and denitrification from flue gas was proposed. Preparation of TiO2 photocatalyst, design of photocatalysis reactor and influencing factors for simul- taneous removal of SO2 and NO, and removal mechanism of SO2 and NO were studied. After the optimal values of concentration of O2 in flue gas, the relative humidity of flue gas and the irradiation time in the photocatalysis reactor were used, the efficiencies of removal for SO2 and NO can be achieved above 98% and about 67%, respectively. According to the results of removal products analysis, the re- moval mechanism of SO2 and NO based on TiO2 photocatlysis can be put forward, namely, SO2 was oxidized to SO3 partly, the bulk of NO was oxidized to NO2, and both were removed by resorbing finally.
