A method to synthesize anticancer drug N-( 4- hydroxyphenyl) retinamide (4-HPR)on a large scale is described. It consists of the preferred steps of reacting all-trans retinoic acid with thionyl chloride to form re...A method to synthesize anticancer drug N-( 4- hydroxyphenyl) retinamide (4-HPR)on a large scale is described. It consists of the preferred steps of reacting all-trans retinoic acid with thionyl chloride to form retinoyl chloride and then reacting with triethylamine to generate retinoyl ammonium salt which in turn is reacted with p-aminophenol to eventually produce 4-HPR. This process can overcome many scale-up challenges that exist in the methods reported in the literature and provide an easy, mild and high yield route for large scale synthesis of 4-HPR. Moreover, the effects of the molar ratios of the reagents on the yield are examined. The best molar ratios are a 2.0 molar equivalence of thionyl chloride and a 3.0 molar equivalence of paminophenol to retinoic acid, and the total yield is 80. 7%.展开更多
A novel mathematical model for single particle slurry propylene polymerization rising heterogeneous Ziegler-Natta catalysts has been developed to describe the kinetic behavior, the molecular weight-distribution, the m...A novel mathematical model for single particle slurry propylene polymerization rising heterogeneous Ziegler-Natta catalysts has been developed to describe the kinetic behavior, the molecular weight-distribution, the monomer concentration, the degree of polymerization, the polydispersity index (PDI), etc. This model provides a more valid mathematical description by accounting for the monomer diffusion phenomena at two levels as multigrai model counts, and obtains results that are more applicable to the conditions existing in most polymerizations of industrial interest. Considering that some models on the mesoscale phenomena are so complex that some existingmodeling aspects have to be simplified or even neglected to make the model convenient for use in interesting engineering studies, it is very important to put some effort into determining what sort of numerical analysis works bestfor these problems. For this reason, special attentionis.paid to these studies to explorean efficient algorithm usingadaptive grid-point spacing in a tlnlte-ditterence technique to tlgure out more practical mass transport models andconvection-diffusion models efficiently. The reasonable outcomes, as well as the significant computation time saving, have been achieved, thereby displaying the advantage of this calculation method.展开更多
With the increment of focal elements number in discernment framework,the computation amount in Dezert-Smarandache Theory (DSmT) will exponentially go up. This has been the bottleneck problem to block the wide applicat...With the increment of focal elements number in discernment framework,the computation amount in Dezert-Smarandache Theory (DSmT) will exponentially go up. This has been the bottleneck problem to block the wide application and development of DSmT. Aiming at this difficulty,in this paper,a kind of fast approximate reasoning method in hierarchical DSmT is proposed. Presently,this method is only fit for the case that there are only singletons with assignment in hyper-power set. These singletons in hyper-power set are forced to group through bintree or tri-tree technologies. At the same time,the assignments of singletons in those different groups corresponding to each source are added up respectively,in order to realize the mapping from the refined hyper-power set to the coarsened one. And then,two sources with the coarsened hyper-power set are combined together according to classical DSm Combination rule (DSmC) and Proportional Conflict Redistribution rule No. 5 (PCR5). The fused results in coarsened framework will be saved as the connecting weights between father and children nodes. And then,all assignments of singletons in different groups will be normalized respectively. Tree depth is set,in order to decide the iterative times in hierarchical system. Finally,by comparing new method with old one from different views,the superiority of new one over old one is testified well.展开更多
Considering the difference in driving parameters of buses and social vehicles on the arterial,an arterial traffic signal coordination model that takes into account social vehicles and buses on the basis of the maximum...Considering the difference in driving parameters of buses and social vehicles on the arterial,an arterial traffic signal coordination model that takes into account social vehicles and buses on the basis of the maximum bandwidth is proposed.By using the pre-set parameters of a common cycle,green/red duration and known parameters of bus dwell time distribution,link length and vehicle speed and solving the mixed-integer-linear programming and optimizing the signal offsets,the model obtains the signal control parameters of the green bands both of social vehicles and buses.Finally,taking Wangjiang Road in Hefei as an example,simulation and evaluation are carried out by VISSIM.The results show that the new model has 15.2%and 13.2%reduction in average person delay and number of stops,respectively,compared with the traditional coordinated control method.展开更多
This paper systematically introduces the advantages of several developed countries, i.e., in Britain, Germany, the USA and other developed countries. The author mainly discusses some advanced school enterprise coopera...This paper systematically introduces the advantages of several developed countries, i.e., in Britain, Germany, the USA and other developed countries. The author mainly discusses some advanced school enterprise cooperation models and in combination with China's national conditions, the author examines what we should do and in what ways we should learn from them and improve, in order to facilitate the cooperation education in line with the development of China, thus contributing to the students' occupation career planning in vocational colleges. Therefore, this article has certain reference values.展开更多
This paper presents a novel computational procedure for the maximum dry density of mixed soils containing oversize particles.At first,the large-scale compaction test data for mixed soils are analyzed by an artificial ...This paper presents a novel computational procedure for the maximum dry density of mixed soils containing oversize particles.At first,the large-scale compaction test data for mixed soils are analyzed by an artificial neural network to determine the main factors affecting the compaction.These factors are then imposed on a genetic programming method and a new mathematical equation emerges.The new equation has more conformity with the experimental data in comparison with the previous correction methods.Besides,the mixed soil dry density is associated with most base soil and oversize fraction specifications.With regard to the sensitivity analyses,if the mixed soil contains high percentages of oversize fraction,the mixed soil composition is governed by the specification of oversized grains,such as specific gravity and the maximum grain size and by increasing these factors,the mixed soil dry density is increased.In mixed soil with a low content of oversize,the base soil specification mainly controls the compaction behavior of mixed soil.Furthermore,if the base soil is inherently compacted with greater dry density,adding the oversize slightly improves the mixed soil dry density.In contrast,adding oversized grains to the base soil with a lower dry density produces a mixed soil with greater dry density.By increasing the maximum grain size difference between the oversize fraction and base soil,the dry density of mixed soil is enhanced.展开更多
Historic cities are cultural achievements that are gradually created by inhabitants over the centuries. In developed countries, the conservation of historic cities seems to be generally acknowledged as a method of com...Historic cities are cultural achievements that are gradually created by inhabitants over the centuries. In developed countries, the conservation of historic cities seems to be generally acknowledged as a method of community development that does not depend on huge exploitation. On the other hand, no sufficient countermeasures have been taken in developing countries because most native stakeholders are still interested in development. Here the author could focus on so-called "international cooperation", but urban conservation for historic cities where inhabitants actually live is still a minor consideration except for some government-based conservation projects for monuments and isolated examples of cultural heritage. In this paper, the example was taken of a conservation project which has been carried out by JICA (Japanese International Cooperation Agency) in Damascus, the old capital of Syria. The target area for the project is "Qanawat South". Although the origin of"Qanawat South" dates back to the Roman age, efforts for urban conservation have not been well organized, partly because the area is located outside of the so-called old city registered as a world heritage site. For example, the master plan of 1968 indicated the redistribution of the traditional quarters, while some conservation laws have been restricting the regeneration of the area. Moreover, there is not yet any consensus among the stakeholders concerning the historical value of the quarter, they are still questioning why the area should be conserved rather than being freely sold or developed and what and how they should contribute to conservation. Based on analysis of the actual situation of Qasr al-Hajjaj Street, this paper examines a method called "restoration-type" facade improvement adopted by JICA, for which the final goal is not only to maintain the appearance of the street but also to activate the life of the habitants of the street.展开更多
It is common in China that the employment consciousness of the college students is weak, the professional orientation is not clear and vocational skills are deficient. The gradates lack of cognition about career, and ...It is common in China that the employment consciousness of the college students is weak, the professional orientation is not clear and vocational skills are deficient. The gradates lack of cognition about career, and there are many students changing other jobs frequently, which not only influences personal development, but also is a waste for the company and the country, Under the situation, the colleges should strengthen the college students to understand career planning and plan the lifetime rationally. The paper tries to find out the breakthrough point from the teaching ways and methods of career planning course for college students, proposes experience-based-based-based teaching, blends the second-classroom teaching model in it, and combines the qualities of science and engineering students in western universities, for solving the problems of the existing classroom teaching.展开更多
The reasonability of the adopted capacity load ratio numerical value in urban power grid planning determines the economy of planning level yearly power grid.Too large capacity load ratio will result in the increasing ...The reasonability of the adopted capacity load ratio numerical value in urban power grid planning determines the economy of planning level yearly power grid.Too large capacity load ratio will result in the increasing investment in the early period of power grid construction, however, too small capacity load ratio will make the power grid have poor adaptability, affecting the power supply. Reasonably determining the adopted regional power grid capacity load ratio quantitative numerical value in planning has a strong guiding significance for constructing reliable and economic power grid and preventing power grid from excessive advance or lagging behind the load development. This paper, through the statistics and analysis of a certain regional power grid 2010-2012 three years' power grid daily load characteristics and the investment benefit evaluation of three years' 220KV power grid individual project, makes a preliminary analysis and puts forwards the specific advice on the reasonable values of power ~rid 35-220KV power transformation capacity load ratio.展开更多
文摘A method to synthesize anticancer drug N-( 4- hydroxyphenyl) retinamide (4-HPR)on a large scale is described. It consists of the preferred steps of reacting all-trans retinoic acid with thionyl chloride to form retinoyl chloride and then reacting with triethylamine to generate retinoyl ammonium salt which in turn is reacted with p-aminophenol to eventually produce 4-HPR. This process can overcome many scale-up challenges that exist in the methods reported in the literature and provide an easy, mild and high yield route for large scale synthesis of 4-HPR. Moreover, the effects of the molar ratios of the reagents on the yield are examined. The best molar ratios are a 2.0 molar equivalence of thionyl chloride and a 3.0 molar equivalence of paminophenol to retinoic acid, and the total yield is 80. 7%.
基金Supported by the National High Technology Development Program of China (No.2006AA05Z226), Natural Science Foundation of Zhejiang Province (No.Y105370), National HI-TECH Industrialization Program of China (No.2004-2080), and Science Fund for Distinguished Young Scholars of Zhejiang University (No. 111000-581645).
文摘A novel mathematical model for single particle slurry propylene polymerization rising heterogeneous Ziegler-Natta catalysts has been developed to describe the kinetic behavior, the molecular weight-distribution, the monomer concentration, the degree of polymerization, the polydispersity index (PDI), etc. This model provides a more valid mathematical description by accounting for the monomer diffusion phenomena at two levels as multigrai model counts, and obtains results that are more applicable to the conditions existing in most polymerizations of industrial interest. Considering that some models on the mesoscale phenomena are so complex that some existingmodeling aspects have to be simplified or even neglected to make the model convenient for use in interesting engineering studies, it is very important to put some effort into determining what sort of numerical analysis works bestfor these problems. For this reason, special attentionis.paid to these studies to explorean efficient algorithm usingadaptive grid-point spacing in a tlnlte-ditterence technique to tlgure out more practical mass transport models andconvection-diffusion models efficiently. The reasonable outcomes, as well as the significant computation time saving, have been achieved, thereby displaying the advantage of this calculation method.
基金Supported by the National Natural Science Foundation of China (No. 60804063)
文摘With the increment of focal elements number in discernment framework,the computation amount in Dezert-Smarandache Theory (DSmT) will exponentially go up. This has been the bottleneck problem to block the wide application and development of DSmT. Aiming at this difficulty,in this paper,a kind of fast approximate reasoning method in hierarchical DSmT is proposed. Presently,this method is only fit for the case that there are only singletons with assignment in hyper-power set. These singletons in hyper-power set are forced to group through bintree or tri-tree technologies. At the same time,the assignments of singletons in those different groups corresponding to each source are added up respectively,in order to realize the mapping from the refined hyper-power set to the coarsened one. And then,two sources with the coarsened hyper-power set are combined together according to classical DSm Combination rule (DSmC) and Proportional Conflict Redistribution rule No. 5 (PCR5). The fused results in coarsened framework will be saved as the connecting weights between father and children nodes. And then,all assignments of singletons in different groups will be normalized respectively. Tree depth is set,in order to decide the iterative times in hierarchical system. Finally,by comparing new method with old one from different views,the superiority of new one over old one is testified well.
基金The National Natural Science Foundation of China(No.51878236)。
文摘Considering the difference in driving parameters of buses and social vehicles on the arterial,an arterial traffic signal coordination model that takes into account social vehicles and buses on the basis of the maximum bandwidth is proposed.By using the pre-set parameters of a common cycle,green/red duration and known parameters of bus dwell time distribution,link length and vehicle speed and solving the mixed-integer-linear programming and optimizing the signal offsets,the model obtains the signal control parameters of the green bands both of social vehicles and buses.Finally,taking Wangjiang Road in Hefei as an example,simulation and evaluation are carried out by VISSIM.The results show that the new model has 15.2%and 13.2%reduction in average person delay and number of stops,respectively,compared with the traditional coordinated control method.
文摘This paper systematically introduces the advantages of several developed countries, i.e., in Britain, Germany, the USA and other developed countries. The author mainly discusses some advanced school enterprise cooperation models and in combination with China's national conditions, the author examines what we should do and in what ways we should learn from them and improve, in order to facilitate the cooperation education in line with the development of China, thus contributing to the students' occupation career planning in vocational colleges. Therefore, this article has certain reference values.
文摘This paper presents a novel computational procedure for the maximum dry density of mixed soils containing oversize particles.At first,the large-scale compaction test data for mixed soils are analyzed by an artificial neural network to determine the main factors affecting the compaction.These factors are then imposed on a genetic programming method and a new mathematical equation emerges.The new equation has more conformity with the experimental data in comparison with the previous correction methods.Besides,the mixed soil dry density is associated with most base soil and oversize fraction specifications.With regard to the sensitivity analyses,if the mixed soil contains high percentages of oversize fraction,the mixed soil composition is governed by the specification of oversized grains,such as specific gravity and the maximum grain size and by increasing these factors,the mixed soil dry density is increased.In mixed soil with a low content of oversize,the base soil specification mainly controls the compaction behavior of mixed soil.Furthermore,if the base soil is inherently compacted with greater dry density,adding the oversize slightly improves the mixed soil dry density.In contrast,adding oversized grains to the base soil with a lower dry density produces a mixed soil with greater dry density.By increasing the maximum grain size difference between the oversize fraction and base soil,the dry density of mixed soil is enhanced.
文摘Historic cities are cultural achievements that are gradually created by inhabitants over the centuries. In developed countries, the conservation of historic cities seems to be generally acknowledged as a method of community development that does not depend on huge exploitation. On the other hand, no sufficient countermeasures have been taken in developing countries because most native stakeholders are still interested in development. Here the author could focus on so-called "international cooperation", but urban conservation for historic cities where inhabitants actually live is still a minor consideration except for some government-based conservation projects for monuments and isolated examples of cultural heritage. In this paper, the example was taken of a conservation project which has been carried out by JICA (Japanese International Cooperation Agency) in Damascus, the old capital of Syria. The target area for the project is "Qanawat South". Although the origin of"Qanawat South" dates back to the Roman age, efforts for urban conservation have not been well organized, partly because the area is located outside of the so-called old city registered as a world heritage site. For example, the master plan of 1968 indicated the redistribution of the traditional quarters, while some conservation laws have been restricting the regeneration of the area. Moreover, there is not yet any consensus among the stakeholders concerning the historical value of the quarter, they are still questioning why the area should be conserved rather than being freely sold or developed and what and how they should contribute to conservation. Based on analysis of the actual situation of Qasr al-Hajjaj Street, this paper examines a method called "restoration-type" facade improvement adopted by JICA, for which the final goal is not only to maintain the appearance of the street but also to activate the life of the habitants of the street.
文摘It is common in China that the employment consciousness of the college students is weak, the professional orientation is not clear and vocational skills are deficient. The gradates lack of cognition about career, and there are many students changing other jobs frequently, which not only influences personal development, but also is a waste for the company and the country, Under the situation, the colleges should strengthen the college students to understand career planning and plan the lifetime rationally. The paper tries to find out the breakthrough point from the teaching ways and methods of career planning course for college students, proposes experience-based-based-based teaching, blends the second-classroom teaching model in it, and combines the qualities of science and engineering students in western universities, for solving the problems of the existing classroom teaching.
文摘The reasonability of the adopted capacity load ratio numerical value in urban power grid planning determines the economy of planning level yearly power grid.Too large capacity load ratio will result in the increasing investment in the early period of power grid construction, however, too small capacity load ratio will make the power grid have poor adaptability, affecting the power supply. Reasonably determining the adopted regional power grid capacity load ratio quantitative numerical value in planning has a strong guiding significance for constructing reliable and economic power grid and preventing power grid from excessive advance or lagging behind the load development. This paper, through the statistics and analysis of a certain regional power grid 2010-2012 three years' power grid daily load characteristics and the investment benefit evaluation of three years' 220KV power grid individual project, makes a preliminary analysis and puts forwards the specific advice on the reasonable values of power ~rid 35-220KV power transformation capacity load ratio.