纸币表面细菌的粘附力学建模研究

发布时间：2018-06-01 23:14

本文选题：细菌粘附 + 力学模型　；参考：《中南大学》2012年硕士论文

【摘要】：随着社会生产、生活和建设的不断改善和人类物质、精神文明的不断提高,产生了一系列的环境问题,其中以细菌、病毒等微生物对人类的健康威胁越来越大。医学研究证明纸币不仅是许多疾病传播的载体,也是引起许多疾病的罪魁祸首。而且,人们的健康意识也在不断加强,对周围环境的健康性、安全性要求也越来越高。纸币作为人民日常生活中的必需品,纸币消毒成为人们关注的对象。要想解决纸币消毒的问题,对细菌粘附、清除和预防方面的研究就显得十分重要。要解决细菌的粘附问题,首先要清楚细菌在纸币表面的粘附机理,细菌的粘附机理是解决细菌粘附问题的理论和基础。论文的主要研究内容和结论如下： (1)通过检索国内外细菌粘附力学大量文献,对这些研究成果进行了总结和相关分析,以此为基础,提出了细菌粘附研究的发展方向和需要做的工作。 (2)全面总结和分析了细菌在纸币表面的分布情况,纸币表面的细菌量随着季节变化明显,同时与纸币面值的大小也有关系。通过电镜观察,纸币表面粗糙度与细菌粘附量呈正相关。细菌在纸币表面粘附受多种因素影响,包括：细菌本身、外界环境、纸币表面的情况等,所以在研究粘附力时候要综合考虑多种因素的影响。 (3)较全面的总结和分析了目前细菌粘附表面的力学机理研究成果。在细菌的粘附过程中,分为特异性粘附和非特异性粘附,其中范德华力是普遍存在的粘附力,其他力都是在一定条件情况下存在的。在粘附过程中还存在静电力、毛细作用力、细菌特殊结构产生的作用力、氢键力、化学键力；细菌的细胞结构、纸币表面的情况和外界环境因素都能影响到细菌的粘附。 (4)利用MATLAB可视化软件对几种典型的粘附力进行可视化模拟,加深了对模型的认识和分析。直观显示了各个参数、变量的变化情况,以及对粘附的影响。在细菌与纸币的粘附过程中,当细菌与纸币的距离减小到2×10-7m时,范德华力作用急剧增大,当接触的突起部分半径r2×10-9m时,粗糙度增加,范德华力增大的速度变大。并且,在nm量级,静电力要比范德华力大2个数量级到3个数量级。毛细作用力比静电力也大2个数量级左右。 (5)研究构造了细菌的实体模型。运用ANSYS软件进行模拟,加载载荷进行力学分析,研究分析作用力在细菌细胞的分布情况和变化。这是一种探索性研究,结论的有效与适用性尚不可知,但作为一种尝试是有一定的价值作用的,为更深层次和广泛研究提供一定借鉴。 (6)运用ANSYS软件对细菌的模拟进行了模拟和分析,细胞模型内的应力分布及传递规律是：随着位移的施加,应力沿细胞中心轴传播并同时向其周围传播,但从向周围传播的速度比较慢。由于外在载荷的存在和细胞质的流动,对细胞壁产生内压,由此而发生一些应力分布的变化。而且随着载荷的施加,垂直于载荷加载方向的应力分布情况要比载荷加载方向的应力分布变化要明显。 (7)通过对前面的研究,能够对细菌在纸币表面的粘附及力学情况有全面的了解,使人们在使用纸币的时候能够注意到健康、安全的使用方式,同时对于纸币的杀菌消毒有重要的意义,也为纸质类物品(图书、包装袋等)的杀菌问题提供了理论基础。
[Abstract]:With the continuous improvement of social production, life and construction, and the continuous improvement of human material and spiritual civilization, a series of environmental problems have been created, among which bacteria, viruses and other microorganisms are becoming more and more dangerous to human health. Medical research has proved that paper currency is not only the carrier of many diseases, but also the culprit of many diseases. Moreover, people's health consciousness is also constantly strengthening, and the requirements for the health and safety of the surrounding environment are also getting higher and higher.
Paper money as a necessity in people's daily life, paper money disinfection has become the object of attention. In order to solve the problem of paper currency disinfection, it is very important to study the adhesion, clearance and prevention of bacteria. To solve the problem of bacterial adhesion, the adhesion mechanism of bacteria on the surface of paper money should be clear, and the adhesion mechanism of bacteria is the solution. The theory and foundation of the problem of bacterial adhesion.
The main contents and conclusions of this paper are as follows:
(1) through the retrieval of a large number of domestic and foreign bacterial adhesion mechanics literature, the research results are summarized and related analysis, based on which, the development direction of bacterial adhesion research and the work to be done are put forward.
(2) the distribution of bacteria on the surface of paper money was comprehensively summarized and analyzed. The bacterial quantity on the surface of the paper currency was obvious with the seasonal variation, and it was also related to the size of the paper currency. The surface roughness of the paper currency was positively correlated with the bacterial adhesion. The adhesion of bacteria on the surface of paper money was influenced by many factors, including the bacteria itself, The external environment, the surface of paper money, etc., so in the study of adhesion force, we should take into account the impact of a variety of factors.
(3) a comprehensive summary and analysis of the mechanical mechanism of the bacterial adhesion surface is summarized and analyzed. In the process of bacterial adhesion, it is divided into specific adhesion and non specific adhesion, in which van Edward force is a common adhesion force and other forces are stored under certain conditions. There is still static electricity and fine hair in the process of adhesion. Force, the force produced by the special structure of bacteria, the hydrogen bond force, the chemical bond force, the cell structure of the bacteria, the condition of the paper coin surface and the external environment factors can affect the adhesion of bacteria.
(4) the visual simulation of several typical adhesion forces was simulated with MATLAB visualization software, which deepened the understanding and analysis of the model. It showed each parameter, the change of the variable, and the influence on the adhesion. In the process of adhesion between bacteria and paper money, when the distance between bacteria and paper money decreased to 2 x, Vander Ed Ley acted urgently. As the play increases, when the radius of the contact is R2 * 10-9m, the roughness increases and the speed of the van Edward force increases. And, at the level of nm, the static power is 2 orders of magnitude to 3 orders of magnitude larger than the Fan Dehua force. The capillary force is about 2 orders of magnitude larger than that of the static power.
(5) the solid model of bacteria was constructed. The ANSYS software was used to simulate, load load and analyze the distribution and change of the bacterial cells. This is an exploratory study. The validity and applicability of the conclusion are still unknown, but as a kind of attempt, it has a certain value and is a deeper level. And a wide range of research to provide some reference.
(6) the simulation and analysis of bacterial simulation were carried out by ANSYS software. The stress distribution and transmission law in the cell model were that the stress spread along the center axis of the cell along with the displacement, but the speed of propagation around it was slow. When the load is applied, the stress distribution in the load direction is more obvious than the stress distribution in the loading direction.
(7) through the previous research, we can have a comprehensive understanding of the adhesion and mechanical conditions of bacteria on the surface of paper money, so that people can pay attention to health and safe use when using paper money, and it is of great significance for the sterilization and disinfection of paper money, and also provides the reason for the sterilization of paper materials (books, bags and so on). On the basis.
【学位授予单位】：中南大学
【学位级别】：硕士
【学位授予年份】：2012
【分类号】：R117

【参考文献】