高速剪切乳化机制备纳米氧化锌及形貌控制

提出了应用高速剪切乳化机制备纳米氧化锌材料的新方法,研究了反应时间、pH值、锌盐浓度、乳化机转速和搅拌方式等实验条件对氧化锌纳米材料形貌的影响.与其它方法相比,用该方法制备纳米氧化锌具有方法简单、条件易控、成本低廉、易于量产、纳米结构几何形状均一等优点.     

催化裂化汽油光催化脱硫连续管式反应器数学模型

通过对催化裂化(FCC)汽油萃取-光催化脱硫连续工艺中光催化脱硫反应器的研究,从光的量子性出发,在对FCC汽油光催化脱硫反应器进行合理简化的基础上,建立了光催化脱硫反应器的数学模型.采用隐式差分法对模型求解,求得FCC汽油光催化脱硫反应器中硫化物的浓度、反应温度、光强在径向和轴向的分布.同时,建立了管式光催化反应器中辐射能传递的基本方程和局部体积能量吸收速率的理论模型.并以催化裂化汽油萃取-光催化脱硫连续试验数据验证了模型的可行性.     

Development of <Emphasis Type="Italic">Gossypium barbadense</Emphasis> chromosome segment substitution lines in the genetic standard line TM-1 of <Emphasis Type="Italic">Gossypium hirsutum</Emphasis>

Chromosome segment substitution lines （CSSL） consist of a battery of near-isogenic lines that have been developed and cover the entire genome of some crops. With the exception of one homozygous chromosome segment transferred from a donor parent, the remaining genome of each CSSL line is the same as the recipient parent. It is an ideal material for genome research and particularly QTL mapping. In the present study, we first developed one set of CSSL lines using G hirsutum acc. TM-1 （the genetic standard）, as the recipient parent and G barbadense cv. Hai7124 as the donor parent using molecular assistedlselection in BC5S1-3 generations. The CSSL consisted of 330 different lines, in which 1-4 different lines had the same or overlapping substituted segments. The genetic length of the substituted segments covered 5271.9 cM with an average segment distance of 10.9 cM, 1.5 times the total genetic length of Upland cotton （3514.6 cM）. The substituted segments of each line varied in length, ranging from 3.5 cM for the shortest segment to 23.2 cM in the longest segment. Our CSSL have not yet to cover the entire tetraploid cotton genome, due to the absence of some donor parent interval segments.     

一个关于"公地悲剧"的错误推导

自哈丁"公地悲剧"一文发表后,相关经济结论似乎已经成为常识,但是在几个不同的文献中将这个理论说法模型化却不尽相同,文献[2]中的模型便存在着一些值得探讨的问题.详细分析文[2]中作者关于该模型的推导过程中所存在的数学与逻辑的疑问,并且指出尽管文[2]中导出的结果碰巧是对的,但是其推导方式却是完全错误的,并且该推导方式不适用于一般情况.     

数学分析课程教学改革的几点尝试

结合数学分析课程教学实际,探讨数学分析课程教学内容的处理和教学方法的更新以及师资队伍的建设。     

关于数学分析教学的几点建议

数学分析是数学专业十分重要的一门基础课,文章对数学分析课程教学的改革与实践进行了总结和探讨。     

Observations of passenger flow and verification of a crowd dynamics model

This paper reports observations of passenger flow in the Wuchang railway station in Wuhan, China during the Chinese Traditional Spring Festival in 2006. The data collected are used to verify a crowd dynamics model previously developed. The crowd dynamics model is based on simulating the global movement of each individual under the influence of the surrounding crowd, and the good agreement between the predictions and observations validates the prediction model. The crowd dynamics model suggests that the crowd movement speed is dominated by two factors： the front-back inter-person effect, and the pedestrian＇s self-motive. The first effect gives logarithmic relationship between the crowd speed and crowd density. The second factor depends on the individual motive driven with which people try to divorce themselves from the control of the crowd movement. The prediction model are helpful to guide the design of public traffic systems for effective crowd dispersal.     

广义次序统计量的任意维边际密度函数

广义次序统计量包括许多用以描述有序变量的随机模型,研究广义次序统计量使人们能够采用统一的观点去看待这些具体的模型,揭示其内在的性质。本文用数学归纳法给出了广义次序统计量的任意维边际密度函数的显示表达式,这对进一步探讨广义次序统计量性质具有十分重要的意义。     

概率论与数理统计教学改革的探索和实践

根据地方院校的现状,结合概率论和数理统计教学实践,就如何精心设计授课内容和教学方法等方面提出了本课程教学改革的建议和措施。     

在西藏高校文科专业开设高等数学课程初探

文章针对目前我国高校高等数学的教学现状,阐述了在我区高校文科专业开设高等数学教学的必要性,并在如何加强教材建设、教学方法的改革、师资队伍的建设以及学生学习评价体系的建立等方面做了探索。