Determination of Phase Transitions of <i>p</i>,<i>n</i>-Alkyloxy Benzoic Acid Mesogens Using Legendre Moments and Image Analysis  

作　　者：S. Sreehari Sastry C. Nageswara Rao K. Mallika S. Lakshminarayan Ha Sie Tiong 

机构地区：[1]Department of Chemical Science, Faculty of Science, UniversitiTunku Abdul Rahman, Jalan Universiti, Bandar Barat, Kampar, Malaysia [2]Department of Electronics and Communcation Engineering, K. L. University, Greenfields, Vaddeswaram, India [3]Department of Physics, Acharya Nagarjuna University, Nagarjuna Nagar, India

出　　处：《World Journal of Condensed Matter Physics》2013年第1期54-61,共8页凝固态物理国际期刊（英文）

摘　　要：Phase transition temperatures of p,n-alkyloxy benzoic acids (nOBA, n = 3 to 10 and 12) are investigated basing on the textural image analysis of liquid crystal. The analysis is carried out by the computation of Legendre moments. Textures of the homeotropically aligned compounds are recorded as a function of temperature using POM in arthroscopic mode attached to the hot stage and high resolution camera. A recurrence formula is used to compute the liquid crystal textures based on Legendre polynomial. The discontinuities and fluctuations in the values of Legendre moments as a function of temperature are related to the phase transition temperatures of the sample. This method is successful in conforming or detecting the phase transition temperatures and the present findings are comparable with literature.Phase transition temperatures of p,n-alkyloxy benzoic acids (nOBA, n = 3 to 10 and 12) are investigated basing on the textural image analysis of liquid crystal. The analysis is carried out by the computation of Legendre moments. Textures of the homeotropically aligned compounds are recorded as a function of temperature using POM in arthroscopic mode attached to the hot stage and high resolution camera. A recurrence formula is used to compute the liquid crystal textures based on Legendre polynomial. The discontinuities and fluctuations in the values of Legendre moments as a function of temperature are related to the phase transition temperatures of the sample. This method is successful in conforming or detecting the phase transition temperatures and the present findings are comparable with literature.

关 键 词：Alkyloxybenzoic Acids HOMEOTROPIC Alignment Phase Transitions Textures Legendre Moments Image ANALYSIS 

分 类 号：O6[理学—化学]