Parametric Investigation of Liquid Crystal Mixtures PDF Download

Author: Vinita Dhulia
Publisher: LAP Lambert Academic Publishing
ISBN: 9783659253195
Category :
Languages : en
Pages : 112

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Book Description
While much fundamental research is still performed with pure liquid crystals, industrial applications employ mostly mixtures, composites, or specially doped liquid crystals with tailor-made physical and optical properties.Current progress and large scale application of liquid crystals in optical technology are largely the result of tremendous advances in such new material development efforts.Liquid crystal mixtures formed by different concentrations of the same set of constituents should be regarded as physically and optically different materials.The book contains the experimental work carried on the composite system formed using cholesteric liquid crystal Cholesteryl Pelargonate-(CP)], polymer Poly Methyl Methacrylate(PMMA)] and azobenzene(orange) dye.The parameters that are investigated are the textures, the phase transition temperatures, the absorption in the visible range and infrared absorption.The parameters were investigated for(i)the pure CP, (ii)the composite system formed using CP and PMMA and (iii) for the composite system formed using CP, PMMA and azobenz

Author: Lajos Bata
Publisher: Elsevier
ISBN: 1483150178
Category : Science
Languages : en
Pages : 704

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Book Description
Advances in Liquid Crystal Research and Applications, Volume 1 is a collection of papers presented at the Third Liquid Crystal Conference of the Socialist Countries, held in Budapest on August 27-31, 1979. This volume is comprised of three parts. The first part deals with the phases and structures of liquid crystals through methods employing synthesis, X-ray studies, electron diffraction, and calorimetric determination. The second part discusses molecular dynamics and dynamical methods where mostly dielectric investigations into liquid crystal properties are emphasized. This part includes the developments in the study of molecular dynamics in liquid crystals. Other topics presented in this part are the acousto-optical and ultrasonic relaxation methods. The third part covers the continual properties of liquid crystals: their properties and behavior when exposed to different testing methods and variables. For example, a correlation between viscosity coefficients of starting components and those of their mixtures is attempted, resulting when MBBA and EBBA in different percentages are mixed, that none of their coefficients is found to obey any pronounced law. However, the viscosity coefficients given in the table may serve as reference data for further studies. Physicists; process engineers; and graduate students in physics, chemistry, and materials science fields; and university professors and lecturers related to studies in the field of liquid crystals will find this collection of papers highly informative and rewarding.

Author: Peter J. Collings
Publisher: Oxford University Press, USA
ISBN:
Category : Language Arts & Disciplines
Languages : en
Pages : 632

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Book Description
The Handbook of Liquid Crystal Research deals with all the important recent advances in liquid crystalline materials. It contains in one volume the results of technical and theoretical work done in the last 15 years.

Author: D.M.P. Mingos
Publisher: Springer
ISBN: 3540681183
Category : Technology & Engineering
Languages : en
Pages : 276

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Book Description
The liquid crystalline state may be identified as a distinct and unique state of matter which is characterised by properties which resembles those of both solids and liquids. It was first recognised in the middle of the last century through the study of nerve myelin and derivatives of cholesterol. The research in the area really gathered momentum, however, when as a result of the pioneering work of Gray in the early 1970's organic compounds showing liquid crystalline properties were shown to be suitable to form the basis of display devices in the electronic products. The study of liquid crystals is truly multidisciplinary and has attached the attention of physicists, biologists, chemists, mathematicians and electronics engineers. It is therefore impossible to cover all these aspects fully in two small volumes and therefore it was decided in view of the overall title of the series to concentrate on the structural and bonding aspects of the subject. The Chapters presented in these two volumes have been organised to cover the following fundamental aspects of the subject. The calculation of the structures of liquid crystals, an account of their dynamical properties and a discussion of computer simulations of liquid crystalline phases formed by Gay Berne mesogens. The relationships between molecular conformation and packing are analysed in some detail. The crystal structures of liquid crystal mesogens and the importance of their X ray scattering properties for characterisational purposes are discussed.

Author: E. Priestly
Publisher: Springer Science & Business Media
ISBN: 1468421751
Category : Science
Languages : en
Pages : 358

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Book Description
The existence of liquid crystals has been known for nearly a centu ry; yet it is only in the last ten years that their unique optical, electri cal, electro-optic, and thermal properties have been exploited to any significant extent in such technological applications as digital d~ plays and thermography. Digital watches equipped with liquid-crys tal displays (LCD's) have recently made their debut in the electronic watch market, and the large-scale use of LCD's in a variety of other applications requiring reliable, low-power digital displays is immi nent. There is good reason to believe that liquid crystals will be the first electro-optic materials to find widespread commercial use. Apart from applications, liquid crystals are unique among the phases of matter. Lurking beneath their garish display of color and texture is a great complexity of physical and chemical interaction that is only now beginning to unfold in the face of a decade-old resurgence in all aspects of liquid~rystal research. RCA Laboratories has participated in this resurgence from its beginning in the early 1960's and at present maintains active liquid-crystal programs both in basic re search and in device engineering. In view of the widespread interest in liquid crystals at RCA Labo ratories, an in-house weekly seminar devoted to the subject of liquid crystals was organized in the fall of 1973. The resulting lectures were subsequently published in three issues of the RCA Review and, with the incorporation of much additional material, eventually grew into the present volume.

Author: Dietrich Demus
Publisher: John Wiley & Sons
ISBN: 3527620567
Category : Technology & Engineering
Languages : en
Pages : 530

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Book Description
The Handbook of Liquid Crystals is a unique compendium of knowledge on all aspects of liquid crystals. In over 2000 pages the Handbook provides detailed information on the basic principles of both low- and high-molecular weight materials, as well as the synthesis, characterization, modification, and applications (such as in computer displays or as structural materials) of all types of liquid crystals. The five editors of the Handbook are internationally renowned experts from both industry and academia and have drawn together over 70 leading figures in the field as authors. The four volumes of the Handbook are designed both to be used together or as stand-alone reference sources. Some users will require the whole set, others will be best served with one or two of the volumes. Volume 1 deals with the basic physical and chemical principles of liquid crystals, including structure-property relationships, nomenclature, phase behavior, characterization methods, and general synthesis and application strategies. As such this volume provides an excellent introduction to the field and a powerful learning and teaching tool for graduate students and above. Volumes 2A and 2B concentrate on low-molecular weight materials, for example those typically used in display technology. A high quality survey of the literature is provided along with full details of molecular design strategies, phase characterization and control, and applications development. These volumes are therefore by far the most detailed reference sources on these industrially very important materials, ideally suited for professionals in the field. Volume 3 concentrates on high-molecular weight, or polymeric, liquid crystals, some of which are found in structural applications and others occur as natural products of living systems. A high-quality literature survey is complemented by full detail of the synthesis, processing, analysis, and applications of all important materials classes. This volume is the most comprehensive reference source on these materials, and is therefore ideally suited for professionals in the field.

Author: Jennifer Kirchhoff
Publisher:
ISBN:
Category :
Languages : en
Pages : 157

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Book Description
ABSTRACT: Liquid crystal phases exhibit physical characteristics that lie between those of liquid and crystal phases. The many liquid crystal sub-phases are defined based on the degree of positional and orientational ordering the molecules have and the materials that make up these liquid crystal phases. This thesis presents a study of the molecular packing and physical properties of complex liquid crystal phases using dopants to better examine the stability and packing mechanisms of these phases. It also looks at the dispersion of quantum dots in liquid crystal materials, examining the electro-optical properties of the mixtures. The main goal of this thesis is to examine the effects of dopants on the properties of liquid crystal phases using optical microscopy, differential scanning calorimetry, electro-optical measurements, and X-ray scattering. For those mixtures with quantum dots fluorescence microscopy and photoluminescence measurements were also conducted. Rod-like liquid crystals are commonly used in display applications when the material is in a nematic liquid crystal phase, which is the least ordered phase exhibiting no positional ordering. The more complicated chiral smectic liquid crystal phases, which have a one dimensional layer structure, show potential for faster and tri-stable switching. A chiral rod-like liquid crystal material is doped with both chiral and achiral rod-like liquid crystals to examine the stability of one of the chiral smectic sub-phase, the SmC*FI1 phase. This phase consists of tilted molecules rotating about the cone defined by the tilt angle with a periodicity of three layers and an overall helical structure.

Author: Oleg D. Lavrentovich
Publisher: Springer Science & Business Media
ISBN: 9401005125
Category : Science
Languages : en
Pages : 356

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Book Description
Topological defects are the subject of intensive studies in many different branches of physics ranging from cosmology to liquid crystals and from elementary particles to colloids and biological systems. Liquid crystals are fascinating materials which present a great variety of these mathematical objects and can therefore be considered as an extremely useful laboratory for topological defects. This book is the first attempt to present together complementary approaches to the investigations of topological defects in liquid crystals using theory, experiments and computer simulations.

Author: Shri Singh
Publisher: Springer Nature
ISBN: 303152621X
Category :
Languages : en
Pages : 676

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Book Description

Author: Yuan Ming Huang
Publisher: Trans Tech Publications Ltd
ISBN: 3038136956
Category : Technology & Engineering
Languages : en
Pages : 930

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Book Description
These proceedings comprise a selection of the peer-reviewed papers that were presented at the 2nd International Symposium on Liquid Crystals: Science and Technology. Volume is indexed by Thomson Reuters CPCI-S (WoS). The topics of the 102 papers cover: the physics of liquid crystals, the chemistry of liquid crystals, applications of liquid crystals and related materials. This work will provide guidance to physicists, chemists and materials scientists working in the field of liquid crystals.