Based on the principle of chemical engineering in the multisubject field—drug delivery, the release kinetics of the slab monolithic matrix with an initially linear concentration distribution is studied in this paper....Based on the principle of chemical engineering in the multisubject field—drug delivery, the release kinetics of the slab monolithic matrix with an initially linear concentration distribution is studied in this paper. It can be used to describe the later stage when drug loading is above its solubility limit. A comprehensive model is proposed and the generalized solutions are acquired by Laplace transformation, from which a special case, i.e. a perfect sink has been deduced. According to the derived equations, the concentration profiles in the matrix has been computed and illustrated and the effect of volume of extraction medium on release has been investigated.展开更多
The leaching kinetics of Sb and Fe from antimony-bearing complex sulfides ore was investigated in HCl solution by oxidation?leaching with ozone.The effects of temperature,HCl concentration,stirring speed and particle ...The leaching kinetics of Sb and Fe from antimony-bearing complex sulfides ore was investigated in HCl solution by oxidation?leaching with ozone.The effects of temperature,HCl concentration,stirring speed and particle size on the process were explored.It is found that the recoveries of Sb and Fe reach86.1%and28.8%,respectively,when the reaction conditions are4.0mol/L HCl,900r/min stirring speed at85°C with<0.074mm particle size after50min leaching.XRD analysis indicates that no new solid product forms in the leaching residue and the leaching process can be described by shrinking core model.The leaching of Sb corresponds to diffusion-controlled model at low temperature(15?45°C)and mixed-controlled model at high temperature(45?85°C),and the apparent activation energies are6.91and17.93kJ/mol,respectively.The leaching of Fe corresponds to diffusion-controlled model,and the apparent activation energy is1.99kJ/mol.Three semi-empirical rate equations are obtained to describe the leaching process.展开更多
After decades of researches and discussions on occurrence regularity and control technology of citrus psyl id （Diaphorina citri Kuwayana） and Liberobacter asi-aticum, the occurrence regularity and sampling technique...After decades of researches and discussions on occurrence regularity and control technology of citrus psyl id （Diaphorina citri Kuwayana） and Liberobacter asi-aticum, the occurrence regularity and sampling technique of citrus psyl id in orange forests in Taizhou was defined and the connections between the infection rate and carrying rate of citrus psyl id and Liberobacter asiaticum as wel as the correlations between the Liberobacter asiaticum and citrus yield loss were discussed. This paper discussed the warnings of Liberobacter asiaticum and citrus psylid control index, the economic life span of orange forests was then predicted by building the diseases spreading models with different management styles. At last, the paper put forward the comprehensive prevention and control technology and the concept that Liber-obacter asiaticum was preventable and control able.展开更多
This study presents a conceptual framework based on the new product diffusion and demand theory models. The proposed framework was creating a probability of demand function. Considering effectiveness of demand functio...This study presents a conceptual framework based on the new product diffusion and demand theory models. The proposed framework was creating a probability of demand function. Considering effectiveness of demand function transmitted by adopters, the optimal control policies of pricing are conducted according to the optimal control theorv.展开更多
在纳米介观尺度范围内实现对材料尺寸与形貌的调控,是纳米材料合成、制备、功能化及其应用的关键,对认识并解纳米晶的成核与生长规律具有重要意义.基于单分散氟化物纳米晶合成提出的扩散控制动力学模型(DCK,diffusion-controlled kinet...在纳米介观尺度范围内实现对材料尺寸与形貌的调控,是纳米材料合成、制备、功能化及其应用的关键,对认识并解纳米晶的成核与生长规律具有重要意义.基于单分散氟化物纳米晶合成提出的扩散控制动力学模型(DCK,diffusion-controlled kinetic)和表面化学热力学模型(SCT,surface chemical thermodynamics)旨在探讨纳米晶的成核与生长规律.本文围绕纳米晶的成核、生长机理,在综述前人工作的基础上,归纳和总结了上述模型,有望对纳米晶的可控合成提供理论指导与借鉴.展开更多
Many dynamic optimal control models for advertising make efforts to solve the problem of determining optimal advertising expenditures and other variables of interest over time for a firm or several competing firms,How...Many dynamic optimal control models for advertising make efforts to solve the problem of determining optimal advertising expenditures and other variables of interest over time for a firm or several competing firms,However,after analyzing the extant literature,one can find that few dynamic optimal advertising models available consider the problem within the product diffusion framework.Furthermore,the established models involving product diffusion are inspired by the Bass model,which has been out of date.This paper poses a dynamic optimal advertising model for new products,which considers the product diffusion based on the relative newly developed generalized version of the Bass model.In this paper,the optimal control model is used to derive the optimal advertising expenditure policy,which gives some implications to advertising practice.展开更多
This paper considers the problem about optimization of proportional reinsurance in the setting of diffusion models. The authors take into account non-cheap proportional reinsurance and bankruptcy value simultaneously....This paper considers the problem about optimization of proportional reinsurance in the setting of diffusion models. The authors take into account non-cheap proportional reinsurance and bankruptcy value simultaneously. The objective is to find the risk control policies which maximize the total discounted reserve and the bankruptcy value. Results show that, the optimal risk control policies and corresponding optimal return functions vary, depending both on the range of bankruptcy value and the relationship between the premium rate of insurance and that of reinsurance.展开更多
文摘Based on the principle of chemical engineering in the multisubject field—drug delivery, the release kinetics of the slab monolithic matrix with an initially linear concentration distribution is studied in this paper. It can be used to describe the later stage when drug loading is above its solubility limit. A comprehensive model is proposed and the generalized solutions are acquired by Laplace transformation, from which a special case, i.e. a perfect sink has been deduced. According to the derived equations, the concentration profiles in the matrix has been computed and illustrated and the effect of volume of extraction medium on release has been investigated.
基金Project (51474257) supported by the National Natural Science Foundation of ChinaProject (2015zzts037) supported by the Postgraduate Research and Innovation Projects of Hunan Province,ChinaProject (2015JC3005) supported by the Key Technology Research and Development Program of Hunan Province,China
文摘The leaching kinetics of Sb and Fe from antimony-bearing complex sulfides ore was investigated in HCl solution by oxidation?leaching with ozone.The effects of temperature,HCl concentration,stirring speed and particle size on the process were explored.It is found that the recoveries of Sb and Fe reach86.1%and28.8%,respectively,when the reaction conditions are4.0mol/L HCl,900r/min stirring speed at85°C with<0.074mm particle size after50min leaching.XRD analysis indicates that no new solid product forms in the leaching residue and the leaching process can be described by shrinking core model.The leaching of Sb corresponds to diffusion-controlled model at low temperature(15?45°C)and mixed-controlled model at high temperature(45?85°C),and the apparent activation energies are6.91and17.93kJ/mol,respectively.The leaching of Fe corresponds to diffusion-controlled model,and the apparent activation energy is1.99kJ/mol.Three semi-empirical rate equations are obtained to describe the leaching process.
基金Supported by the Ministry of Agriculture and public service sectors(agriculture)Research and Special Project Funds ‘Comprehensive Prevention and Control Technology Research and Demonstration of Liberibacter americanus and Canker’(201003067)Science and Technology Planning Project of Zhejiang Province ‘Research of Surveillance and Control Strategy of Liberibacter americanus’(2004C32087)~~
文摘After decades of researches and discussions on occurrence regularity and control technology of citrus psyl id （Diaphorina citri Kuwayana） and Liberobacter asi-aticum, the occurrence regularity and sampling technique of citrus psyl id in orange forests in Taizhou was defined and the connections between the infection rate and carrying rate of citrus psyl id and Liberobacter asiaticum as wel as the correlations between the Liberobacter asiaticum and citrus yield loss were discussed. This paper discussed the warnings of Liberobacter asiaticum and citrus psylid control index, the economic life span of orange forests was then predicted by building the diseases spreading models with different management styles. At last, the paper put forward the comprehensive prevention and control technology and the concept that Liber-obacter asiaticum was preventable and control able.
文摘This study presents a conceptual framework based on the new product diffusion and demand theory models. The proposed framework was creating a probability of demand function. Considering effectiveness of demand function transmitted by adopters, the optimal control policies of pricing are conducted according to the optimal control theorv.
文摘在纳米介观尺度范围内实现对材料尺寸与形貌的调控,是纳米材料合成、制备、功能化及其应用的关键,对认识并解纳米晶的成核与生长规律具有重要意义.基于单分散氟化物纳米晶合成提出的扩散控制动力学模型(DCK,diffusion-controlled kinetic)和表面化学热力学模型(SCT,surface chemical thermodynamics)旨在探讨纳米晶的成核与生长规律.本文围绕纳米晶的成核、生长机理,在综述前人工作的基础上,归纳和总结了上述模型,有望对纳米晶的可控合成提供理论指导与借鉴.
基金This research is supported by the National Natural Science Foundation of China.
文摘Many dynamic optimal control models for advertising make efforts to solve the problem of determining optimal advertising expenditures and other variables of interest over time for a firm or several competing firms,However,after analyzing the extant literature,one can find that few dynamic optimal advertising models available consider the problem within the product diffusion framework.Furthermore,the established models involving product diffusion are inspired by the Bass model,which has been out of date.This paper poses a dynamic optimal advertising model for new products,which considers the product diffusion based on the relative newly developed generalized version of the Bass model.In this paper,the optimal control model is used to derive the optimal advertising expenditure policy,which gives some implications to advertising practice.
文摘This paper considers the problem about optimization of proportional reinsurance in the setting of diffusion models. The authors take into account non-cheap proportional reinsurance and bankruptcy value simultaneously. The objective is to find the risk control policies which maximize the total discounted reserve and the bankruptcy value. Results show that, the optimal risk control policies and corresponding optimal return functions vary, depending both on the range of bankruptcy value and the relationship between the premium rate of insurance and that of reinsurance.
