Liquid Crystals Reviews最新文献_第3页

Lehmann effect in nematic and cholesteric liquid crystals: a review 向列型和胆甾醇型液晶中的莱曼效应

IF 5.1 3区材料科学

Liquid Crystals Reviews Pub Date : 2019-07-03 DOI: 10.1080/21680396.2019.1671244

P. Oswald, A. Dequidt, G. Poy

{"title":"Lehmann effect in nematic and cholesteric liquid crystals: a review","authors":"P. Oswald, A. Dequidt, G. Poy","doi":"10.1080/21680396.2019.1671244","DOIUrl":"https://doi.org/10.1080/21680396.2019.1671244","url":null,"abstract":"ABSTRACT The Lehmann effect is the continuous rotation of cholesteric droplets subjected to a temperature gradient. Discovered by Otto Lehmann in 1900, this effect was re-observed recently by several authors not only in cholesterics but also in nematics when the director field is twisted inside the droplets. In most experiments, the droplets coexist with their isotropic liquid, but the Lehmann effect can also be observed when the droplets are dispersed in an isotropic liquid in which the LC is partly miscible. After a brief history on the Lehmann effect and its first explanation by Leslie in 1968, we will review the main experimental results obtained on this subject from 2008. In particular, the role of the temperature gradient, of the size of the droplets, of the textures and their orientation with respect to the temperature gradient, of the confinement effects, of the impurities and of the concentration of chiral molecules will be described. A special emphasis will also be placed on the research of hydrodynamic effects to answer the fundamental question of whether it is just the texture or the droplet itself that rotates. We will then review the different models proposed in the literature to explain the Lehmann effect. Among them are two thermomechanical models directly based on the Leslie explanation (named TM1 and TM2 models), a thermomechanical model of rotating texture ‘surfing’ on a heat wave (TM3 model), a model of melting-growth (MG model) that only applies when the droplets coexist with their own isotropic liquid, and a pure hydrodynamic model (H model) based on the existence of Marangoni flows – currently, only evidenced in emulsified cholesterics. The strengths and weaknesses of each model will be discussed in relation with the experimental results.","PeriodicalId":18087,"journal":{"name":"Liquid Crystals Reviews","volume":"7 1","pages":"142 - 166"},"PeriodicalIF":5.1,"publicationDate":"2019-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/21680396.2019.1671244","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49480140","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 17

Recent advancements in the mesogens comprising of 1,3,5-triazine core moiety 1,3,5-三氮嘧啶核片段的介原研究进展

IF 5.1 3区材料科学

Liquid Crystals Reviews Pub Date : 2019-07-03 DOI: 10.1080/21680396.2019.1666753

Deepak Devadiga, T. N. Ahipa

{"title":"Recent advancements in the mesogens comprising of 1,3,5-triazine core moiety","authors":"Deepak Devadiga, T. N. Ahipa","doi":"10.1080/21680396.2019.1666753","DOIUrl":"https://doi.org/10.1080/21680396.2019.1666753","url":null,"abstract":"ABSTRACT Research works on new discoid molecules, comprehending an aromatic/heteroaromatic rigid core with flexible peripheral chains, have been gathered with the multiplying attentiveness due to their prime importance as prototype systems for the charge and energy transport investigation and owing to the prospect of their organo-electronic applications. This critical review article delineates the recent headway in the fundamental design ideas and the available synthetic approaches to obtain the most often encountered triazine-based discotic liquid crystals. The major focal point of the review is to explore the exhilarating research on 1,3,5-triazine-based mesogens that has been reported in the last 5 years. Moreover, the current review not only highlights the variety of structural modifications that are undertaken by the various researchers across the globe in the field of 1,3,5-triazine-based discoid molecules, but also facilitates the fascinating and beneficial altering of properties, both for the rudimentary intentions of demonstrating structure–property relationships and for materials focused in the direction of commercially triumphant liquid crystal display and other applications. GRAPHICAL ABSTRACT","PeriodicalId":18087,"journal":{"name":"Liquid Crystals Reviews","volume":"7 1","pages":"107 - 141"},"PeriodicalIF":5.1,"publicationDate":"2019-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/21680396.2019.1666753","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48865360","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 14

The role of hydrogen bonds in the mesomorphic behaviour of supramolecular assemblies organized in dendritic architectures 氢键在树枝状结构超分子组装体介晶行为中的作用

IF 5.1 3区材料科学

Liquid Crystals Reviews Pub Date : 2019-01-02 DOI: 10.1080/21680396.2019.1621226

M. Arkas, I. Kitsou, A. Gkouma, M. Papageorgiou

{"title":"The role of hydrogen bonds in the mesomorphic behaviour of supramolecular assemblies organized in dendritic architectures","authors":"M. Arkas, I. Kitsou, A. Gkouma, M. Papageorgiou","doi":"10.1080/21680396.2019.1621226","DOIUrl":"https://doi.org/10.1080/21680396.2019.1621226","url":null,"abstract":"ABSTRACT Dendritic polymers are artificial compounds with a unique, repeatedly branched structure inspired by the respective patterns, encountered in trees. They are recognized as the fourth major macromolecular architectural class next to linear, cross linked and branched polymers. Regarding the formation of liquid crystalline phases, they follow the same rules as all the other categories. Suitable chemical functionalization induces segregation. Secondary interactions, in the form of hydrogen bonds in particular, also play a crucial role in mesophase formation by regulating polarity fluctuations and other properties such as rigidity. As a consequence, there are some cases where liquid crystallinity is attributed exclusively to the presence of hydrogen bonding networks, whereas in many more examples mesophase formation is induced mainly due to these interactions. A survey of intra and intermolecular bond influence on the liquid crystalline character of dendritic polymers is presented. The review also covers some examples of supramolecular assemblies exhibiting architecture or incorporating elements reminiscent of trees which cannot be classified as dendritic polymers where segregation resulting by hydrogen bonding is governed by the same principles. In parallel, a description of the various mesophases observed in correlation to different hydrogen bonding patterns is included, and some general conclusions and rules are suggested.","PeriodicalId":18087,"journal":{"name":"Liquid Crystals Reviews","volume":"7 1","pages":"105 - 60"},"PeriodicalIF":5.1,"publicationDate":"2019-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/21680396.2019.1621226","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49298062","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 8

Tailoring surface patterns to direct the assembly of liquid crystalline materials 定制表面图案以指导液晶材料的组装

IF 5.1 3区材料科学

Liquid Crystals Reviews Pub Date : 2019-01-02 DOI: 10.1080/21680396.2019.1598295

Yu Xia, Apiradee Honglawan, Shu Yang

引用次数: 16

Interaction and self-organization of inclusions in two-dimensional free-standing smectic films 二维独立晶膜中夹杂物的相互作用和自组织

IF 5.1 3区材料科学

Liquid Crystals Reviews Pub Date : 2019-01-02 DOI: 10.1080/21680396.2019.1586590

P. Dolganov, P. Cluzeau, V. Dolganov

引用次数: 16

Lipid-based Liquid Crystalline Films and Solutions for the Delivery of Cargo to Cells. 用于向细胞输送货物的脂基液晶薄膜和解决方案。

IF 5.1 3区材料科学

Liquid Crystals Reviews Pub Date : 2019-01-01 Epub Date: 2019-11-04 DOI: 10.1080/21680396.2019.1666752

Marilyn Porras-Gomez, Cecilia Leal

{"title":"Lipid-based Liquid Crystalline Films and Solutions for the Delivery of Cargo to Cells.","authors":"Marilyn Porras-Gomez, Cecilia Leal","doi":"10.1080/21680396.2019.1666752","DOIUrl":"10.1080/21680396.2019.1666752","url":null,"abstract":"A major challenge in the delivery of cargo (genes and/or drugs) to cells using nanostructured vehicles is the ability to safely penetrate plasma membranes by escaping the endosome before degradation, later releasing the payload into the cytoplasm or organelle of interest. Lipids are a class of bio-compatible molecules that self-assemble into a variety of liquid crystalline constructs. Most of these materials can be used to encapsulate drugs, proteins, and nucleic acids to deliver them safely into various cell types. Lipid phases offer a plethora of structures capable of forming complexes with biomolecules, most notably nucleic acids. The physichochemical characteristics of the lipid molecular building blocks, one might say the lipid primary structure, dictates how they collectively interact to assemble into various secondary structures. These include bilayers, lamellar stacks of bilayers, two-dimensional (2D) hexagonal arrays of lipid tubes, and even 3D cubic constructs. The liquid crystalline materials can be present in the form of aqueous suspensions, bulk materials or confined to a film configuration depending on the intended application (e.g. bolus vs surface-based delivery). This work compiles recent findings of different lipid-based liquid crystalline constructs both in films and particles for gene and drug delivery applications. We explore how lipid primary and secondary structures endow liquid crystalline materials with the ability to carry biomolecular cargo and interact with cells.","PeriodicalId":18087,"journal":{"name":"Liquid Crystals Reviews","volume":"7 2","pages":"167-182"},"PeriodicalIF":5.1,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6961842/pdf/nihms-1541372.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"37545922","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Interpretation of saddle-splay and the Oseen-Frank free energy in liquid crystals 液晶中鞍展开和Oseen-Frank自由能的解释

IF 5.1 3区材料科学

Liquid Crystals Reviews Pub Date : 2018-07-03 DOI: 10.1080/21680396.2019.1581103

Jonathan V Selinger

引用次数: 72

Nematicons: reorientational solitons from optics to photonics 向列矩阵:从光学到光子学的重定向孤子

IF 5.1 3区材料科学

Liquid Crystals Reviews Pub Date : 2018-07-03 DOI: 10.1080/21680396.2019.1588797

G. Assanto

引用次数: 24

Ferroelectric liquid crystal nanocomposites: recent development and future perspective 铁电液晶纳米复合材料的最新发展与展望

IF 5.1 3区材料科学

Liquid Crystals Reviews Pub Date : 2018-07-03 DOI: 10.1080/21680396.2019.1589400

S. Yadav, Kanchan Yadav, J. Lahiri, Avanish Singh Parmar

引用次数: 15

Pierre-Gilles de Gennes and physics of liquid crystals Pierre-Gilles de Gennes和液晶物理学

IF 5.1 3区材料科学

Liquid Crystals Reviews Pub Date : 2018-07-03 DOI: 10.1080/21680396.2018.1474813

A. A. Sonin

引用次数: 5