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关键词： addition polymerization   mathematical analysis   molecule sizes   polystyrene   spinning disc reactor  

摘要： A mathematical analysis of the behaviour of the molecular weights of addition polymers during a polymerisation process is described. Spinning disc reactor (SDR) technology has been shown to yield significant improvements in terms of polymerisation rates whilst retaining close control of the molecular weights and the molecular weight distributions([1,2]). However, understanding of the kinetics of the polymerisation process on a SDR remains unresolved. One of the questions to be addressed concerns the sizes of the macromolecules preferably formed during the polymerisation process. To address this question, a mathematical analysis of the observed trends in number and weight average molecular weight, monomer concentration and polydispersity during the polymerisation process on a SDR has been undertaken. To validate the results, experimental data obtained from benzoyl peroxide initiated free radical polymerisation of styrene on a SDR[2] was used. It was concluded that most of the monomers consumed are in the growth of smaller size chains.

ISBN: (纸本)704014364X

关键词： ozone   aerosol heterogeneous chemistry   nonlinear system   multiequilibrium   catastrophe  

摘要： The impact of odd chlorine (Cl-y) and odd nitrogen (NOy) perturbations (resulting from human activities) and of enhanced H2O-H2SO4 aerosol load (associated with volcanic activity) on stratospheric ozone (25 km altitude, midlatitudes) is assessed by using a chemical box model in which key heterogeneous reactions on the surface of sulfate aerosol particles are taken into account. The model shows that if transport is ignored, the response of the photochemical system to increased abundances of odd chlorine and odd nitrogen and to enhanced aerosol surface area density is characterized by a multiequilibrium regime. Catastrophic transitions may occur and may produce dramatic reductions in the stratospheric ozone concentration. When the dissipative effects associated with transport are taken into account, the system still exhibits a nonlinear response to external nitrogen and chlorine sources but without multiequilibrium solutions or catastrophic transitions. Over a sensitive interval, small external disturbances applied to model parameters can lead to large changes in the state of the system. For example, the large drop in ozone derived by the model when dissipative transport effects are taken into account corresponds to a degeneracy of the multiequilibrium regime found when dissipative terms are omitted.

关键词： 斑岩   矿山地质   矿体   数学分析   地质特征  

摘要： 通过对生产矿山回访 ,发现一些斑岩中的矿体变化较大 ,因而对比之下提出在初期圈矿过程中 ,对地质资料加强分析 。

关键词： 复合函数极限   数学教学   数学分析   极限  

摘要： 复合函数极限问题在数学教学中经常遇到。复合函数极限当外层函数y =f(u)在u =a处不连续的情况下 ,limx→r0f[φ(x) ]=limu→af(u)

关键词： 数学分析   极限   放大法  

摘要： 以数列极限为例,详细阐述了用极限定义证明极限存在的三种常用的方法:基本方法、适当放大法、条件放大法,以及在应用这些方法时应注意的一些主要问题,从而强化对极限概念的理解·

关键词： 推广的黎曼引理   积分第一中值定理   极限   黎曼积分   应用  

摘要： 本文介绍了推广的黎曼引理在傅立叶级数积分收敛证明中的应用,通过引入辅助函数和积分第一中值定理对 该定理进行了证明,然后将推广的黎曼引理用于黎曼引理的证明和数学分析中傅立叶级数积分收敛某些题的证明中,证明 比《数学分析》书中简洁,所证明的结果再用于计算题中,这样使抽象的数学证明和计算变得具有趣味了。

关键词： 中值定理   证题方法   “两点函数值之差”   不等式   数学分析   柯西定理  

摘要： 利用中值定理来证明等式和不等式的证题方法。

ISBN: (纸本)7030137302

关键词： 数控车削   数学分析   车刀   刀尖圆弧   数控车床  

摘要： 从数学角度就车刀刀尖圆弧对数控车削加工的影响进行了分析 。