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1.
A dynamic mathematical model is developed for production of Cerenol polyether from 1,3‐propanediol in a batch reactor system. The model accounts for polycondensation reactions and side reactions in the liquid phase and for mass transfer of volatile species to the vapor. Parameters are estimated using measured liquid‐phase concentrations of monomer, oligomers, water, and end groups as well as the mass and composition of condensate collected from the overhead condenser system. The proposed model uses novel probability factors to keep the model equations relatively simple while accounting for the complex influence of superacid catalyst on reaction rates. The model is a significant advance over previous Cerenol models because it better accounts for mass‐transfer rates and for the dynamic behavior of the condenser. In addition, the proposed model accounts for the inhibitory influence of water on polycondensation kinetics due to hydration of hydroxyl ends. The model equations and parameter estimates provide a substantial improvement in fit to the data, especially for long reaction times and high catalyst levels, resulting in a 97% reduction in the value of the weighted least squared objective function compared to equations and parameters from a previous model. 相似文献
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N. Dinh M. A. Goberna M. A. López T. H. Mo 《Journal of Optimization Theory and Applications》2017,173(2):357-390
The main purpose of this paper consists of providing characterizations of the inclusion of the solution set of a given conic system posed in a real locally convex topological space into a variety of subsets of the same space defined by means of vector-valued functions. These Farkas-type results are used to derive characterizations of the weak solutions of vector optimization problems (including multiobjective and scalar ones), vector variational inequalities, and vector equilibrium problems. 相似文献
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Le Thi Phuong Ngoc Nguyen Anh Triet Alain Pham Ngoc Dinh 《Numerical Functional Analysis & Optimization》2017,38(9):1173-1207
In this paper, we consider a wave equation with integral nonlocal boundary conditions of memory type. First, we establish two local existence theorems by using Faedo–Galerkin method and standard arguments of density. Next, we give a su?cient condition to guarantee the global existence and exponential decay of weak solutions. Finally, we present numerical results. 相似文献
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We prove the global solvability and weakly asymptotic stability for a semilinear fractional differential inclusion subject to impulsive effects by analyzing behavior of its solutions on the half-line. Our analysis is based on a fixed point principle for condensing multi-valued maps, which is employed for solution operator acting on the space of piecewise continuous functions. The obtained results will be applied to a lattice fractional differential system. 相似文献
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Thuan Nguyen Ngoc Ngan Nguyen Thi Kuo Ping-Chung Trinh Nguyen Thi Nu Thien Le Trung Mai Dam Sao Tuan Nguyen Ngoc Tan Le Van Thang Tran Dinh 《Chemistry of Natural Compounds》2021,57(6):1104-1106
Chemistry of Natural Compounds - 相似文献
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With impressive progress in carbon capture and renewable energy, carbon dioxide (CO2) conversion into useful chemicals has become a potential tool against climate change. Electrochemical CO2 conversion into C2 products (ethylene and ethanol) is an especially economically promising approach and an active research area. Nonetheless, catalyst layer design for CO2 conversion is challenging because of the complex CO2-to-C2 reaction pathways. In this review, we highlight key ideas in catalyst layer design for CO2 conversion to C2 in the past few years. We identify three fundamental principles to control catalyst selectivity—local CO2 and CO concentration, local pH, and intermediate–catalyst interaction. To achieve these goals, we introduce design strategies for both catalytic materials and overall catalyst layer morphology. 相似文献
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