In this work, esterification of acetic acid and methanol to synthesize methyl acetate in a batch stirred reactor is studied in the temperature range of 305.15–333.15 K. Sulfuric acid is used as the homogeneous cataly...In this work, esterification of acetic acid and methanol to synthesize methyl acetate in a batch stirred reactor is studied in the temperature range of 305.15–333.15 K. Sulfuric acid is used as the homogeneous catalyst with concentrations ranging from 0.0633 mol·L-1to 0.3268 mol·L-1. The feed molar ratio of acetic acid to methanol is varied from 1:1 to 1:4. The influences of temperature, catalyst concentration and reactant concentration on the reaction rate are investigated. A second order kinetic rate equation is used to correlate the experimental data. The forward and backward reaction rate constants and activation energies are determined from the Arrhenius plot.The developed kinetic model is compared with the models in literature. The developed kinetic equation is useful for the simulation of reactive distillation column for the synthesis of methyl acetate.展开更多
A modified systematic approach to determination of the kinetics of well known reaction from calorimetric data is addressed in this study. Because the application of calorimetry does not depend upon knowledge of concen...A modified systematic approach to determination of the kinetics of well known reaction from calorimetric data is addressed in this study. Because the application of calorimetry does not depend upon knowledge of concentration profiles, it has the advantage over other real-time analyses. Estimated kinetic parameters were compared with the ones obtained with Fourier Transform Infrared Spectroscopy （FTIR）. The chosen reaction was ethyl benzoate saponification performed in homogeneous reaction medium, although it is known as heterogeneous reaction. Thus, the rate expression was developed where no mass transfer is considered. The reaction was carried out in a MettlerTM RCI reaction calorimeter.展开更多
Plant height and tillering are crucial factors determining rice plant architecture and influencing rice grain production. In this study, rnulti-tillering dwarf1 （mtdl）, a stable multi-tiller and dwarf mutant, was sc...Plant height and tillering are crucial factors determining rice plant architecture and influencing rice grain production. In this study, rnulti-tillering dwarf1 （mtdl）, a stable multi-tiller and dwarf mutant, was screened from the ethylmethane sulfonate-treated japonica rice variety Wuyunging7. Compared with the wild type, mtdl mutant exhibited pleiotropic phenotypes, including dwarf- ism, more tillers, brittle culms and delayed heading date. By employing map-based cloning strategy, the gene MTD1 was finally mapped to an approximately 66-kb region on the short arm of chromosome 9. Sequencing results showed that the gene LOCOsO9g02650 （BC12） in mtdl mutant had a single nucleotide substitution （G to A）, which gen- erated a premature translation stop. Over-expressing MTD1/BC12 coding sequ（nce rescued all the phenotypes of mtdl mutants including plant height and tillers, which confirms that BC12 is the mutated gene in mtdl mutant. Quantitative reverse tran,-eription-PCR analysis showed that MTDI/BCI2 could negatively regulate the expression of MONOCULM 1, IDEAL PLANT ARCHITECTURE1 and Tillering and Dwarf 1, and control rice tillering. Remark- ably, a-amylase activity analysis and gibberellic acid （GA） treatment showed that the dwarf phenotype of mtdl mutant was dependent on GA biosynthesis pathway. These results facilitated to further uncover the molecular mechanism of the growth and development in rice.展开更多
文摘In this work, esterification of acetic acid and methanol to synthesize methyl acetate in a batch stirred reactor is studied in the temperature range of 305.15–333.15 K. Sulfuric acid is used as the homogeneous catalyst with concentrations ranging from 0.0633 mol·L-1to 0.3268 mol·L-1. The feed molar ratio of acetic acid to methanol is varied from 1:1 to 1:4. The influences of temperature, catalyst concentration and reactant concentration on the reaction rate are investigated. A second order kinetic rate equation is used to correlate the experimental data. The forward and backward reaction rate constants and activation energies are determined from the Arrhenius plot.The developed kinetic model is compared with the models in literature. The developed kinetic equation is useful for the simulation of reactive distillation column for the synthesis of methyl acetate.
文摘A modified systematic approach to determination of the kinetics of well known reaction from calorimetric data is addressed in this study. Because the application of calorimetry does not depend upon knowledge of concentration profiles, it has the advantage over other real-time analyses. Estimated kinetic parameters were compared with the ones obtained with Fourier Transform Infrared Spectroscopy （FTIR）. The chosen reaction was ethyl benzoate saponification performed in homogeneous reaction medium, although it is known as heterogeneous reaction. Thus, the rate expression was developed where no mass transfer is considered. The reaction was carried out in a MettlerTM RCI reaction calorimeter.
基金supported by the National Natural Science Foundation of China (31401464, 31201183)Zhejiang Provincial Natural Science Foundation of China (Y3110194, LY16C130001)+1 种基金China Postdoctoral Science Foundation (2014M561108)the Open Foundation from Zhejiang Provincial Top Key Discipline of Biology (KFJJ2014006)
文摘Plant height and tillering are crucial factors determining rice plant architecture and influencing rice grain production. In this study, rnulti-tillering dwarf1 （mtdl）, a stable multi-tiller and dwarf mutant, was screened from the ethylmethane sulfonate-treated japonica rice variety Wuyunging7. Compared with the wild type, mtdl mutant exhibited pleiotropic phenotypes, including dwarf- ism, more tillers, brittle culms and delayed heading date. By employing map-based cloning strategy, the gene MTD1 was finally mapped to an approximately 66-kb region on the short arm of chromosome 9. Sequencing results showed that the gene LOCOsO9g02650 （BC12） in mtdl mutant had a single nucleotide substitution （G to A）, which gen- erated a premature translation stop. Over-expressing MTD1/BC12 coding sequ（nce rescued all the phenotypes of mtdl mutants including plant height and tillers, which confirms that BC12 is the mutated gene in mtdl mutant. Quantitative reverse tran,-eription-PCR analysis showed that MTDI/BCI2 could negatively regulate the expression of MONOCULM 1, IDEAL PLANT ARCHITECTURE1 and Tillering and Dwarf 1, and control rice tillering. Remark- ably, a-amylase activity analysis and gibberellic acid （GA） treatment showed that the dwarf phenotype of mtdl mutant was dependent on GA biosynthesis pathway. These results facilitated to further uncover the molecular mechanism of the growth and development in rice.
