Thermodynamics of structured fluids. Hard science for soft materials

At liquid-like densities, molecules of complex fluids can assume a variety of structures (or positions) in space; when the molecules contain many atoms as, for example, in polymers, that variety becomes very large. Further, when confined to a narrow space, it is possible to achieve structures that are not normally observed. Thanks to recent advances in statistical mechanics and molecular physics, and thanks to increasingly fast computers, it is now possible to calculate a fluid's structure, that is, the positions of molecules at equilibrium under given conditions. Calculation of fluid structure is useful because thermodynamic properties depend strongly on that structure, leading to possible applications for new materials. Three examples illustrate some recent developments; each example is presented only schematically (with a minimum of equations) to indicate the physical basis of the mathematical description. The first example considers the effect of branching on self-assembly (micellization) of copolymers (with possible long-range applications in medicine). The second and third examples consider the effect of confinement on fluid structure: first, crystallization in a narrow, confined space to produce a desired crystal structure (with possible applications for light-emitting diodes) and second, suppression of micellization of a diblock copolymer in a thin film (with possible application in lithography). Whenever possible, theoretical calculations are compared with experimental results.

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Recent developments in the construction of metallacycle/metallacage-cored supramolecular polymers via hierarchical self-assembly

Chemical Communications ◽

10.1039/c9cc02472g ◽

2019 ◽

Vol 55 (56) ◽

pp. 8036-8059 ◽

Cited By ~ 28

Author(s):

Bo Li ◽

Tian He ◽

Yiqi Fan ◽

Xinchao Yuan ◽

Huayu Qiu ◽

...

Keyword(s):

Self Assembly ◽

Recent Progress ◽

Supramolecular Polymers ◽

Feature Article ◽

Light Emitting ◽

Recent Developments ◽

Potential Applications ◽

Bio Imaging

This feature article summarized the recent progress on the construction of metallacycle/metallacage-cored supramolecular polymers by the hierarchical self-assembly, and the potential applications in the areas of light emitting, sensing, bio-imaging, delivery and release, etc., are also presented.

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Recent Developments in Carbon Nanotubes-Reinforced Ceramic Matrix Composites: A Review on Dispersion and Densification Techniques

Crystals ◽

10.3390/cryst11050457 ◽

2021 ◽

Vol 11 (5) ◽

pp. 457

Author(s):

Kar Fei Chan ◽

Mohd Hafiz Mohd Zaid ◽

Md Shuhazlly Mamat ◽

Shahira Liza ◽

Masaki Tanemura ◽

...

Keyword(s):

Carbon Nanotubes ◽

Turbine Blades ◽

Glass Ceramics ◽

Ceramic Matrix Composites ◽

Ceramic Matrix ◽

Matrix Composites ◽

Catalytic Reactors ◽

Light Emitting ◽

Commercial Laboratory ◽

Recent Developments

Ceramic matrix composites (CMCs) are well-established composites applied on commercial, laboratory, and even industrial scales, including pottery for decoration, glass–ceramics-based light-emitting diodes (LEDs), commercial cooking utensils, high-temperature laboratory instruments, industrial catalytic reactors, and engine turbine blades. Despite the extensive applications of CMCs, researchers had to deal with their brittleness, low electrical conductivity, and low thermal properties. The use of carbon nanotubes (CNTs) as reinforcement is an effective and efficient method to tailor the ceramic structure at the nanoscale, which provides considerable practicability in the fabrication of highly functional CMC materials. This article provides a comprehensive review of CNTs-reinforced CMC materials (CNTs-CMCs). We critically examined the notable challenges during the synthesis of CNTs-CMCs. Five CNT dispersion processes were elucidated with a comparative study of the established research for the homogeneity distribution in the CMCs and the enhanced properties. We also discussed the effect of densification techniques on the properties of CNTs-CMCs. Additionally, we synopsized the outstanding microstructural and functional properties of CNTs in the CNTs-CMCs, namely stimulated ceramic crystallization, high thermal conductivity, bandgap reduction, and improved mechanical toughness. We also addressed the fundamental insights for the future technological maturation and advancement of CNTs-CMCs.

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Aluminate Red Phosphor in Light-Emitting Diodes: Theoretical Calculations, Charge Varieties, and High-Pressure Luminescence Analysis

ACS Applied Materials & Interfaces ◽

10.1021/acsami.7b06840 ◽

2017 ◽

Vol 9 (28) ◽

pp. 23995-24004 ◽

Cited By ~ 26

Author(s):

Niumiao Zhang ◽

Yi-Ting Tsai ◽

Mu-Huai Fang ◽

Chong-Geng Ma ◽

Agata Lazarowska ◽

...

Keyword(s):

High Pressure ◽

Light Emitting Diodes ◽

Theoretical Calculations ◽

Luminescence Analysis ◽

Red Phosphor ◽

Light Emitting

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Molecular materials for micro-electronics

Canadian Journal of Physics ◽

10.1139/p00-033 ◽

2000 ◽

Vol 78 (3) ◽

pp. 231-241 ◽

Cited By ~ 3

Author(s):

M D'Iorio

Keyword(s):

High Performance ◽

Organic Materials ◽

Coming Of Age ◽

Polymeric Materials ◽

Organic Light Emitting Diodes ◽

Light Emitting ◽

Light Emitting Devices ◽

Plastic Electronics ◽

Organic Light ◽

Recent Developments

Molecular organic materials have had an illustrious past but the ability to deposit these as homogeneous thin films has rejuvenated the field and led to organic light-emitting diodes (OLEDs) and the development of an increasing number of high-performance polymers for nonlinear and electronic applications. Whereas the use of organic materials in micro-electronics was restricted to photoresists for patterning purposes, polymeric materials are coming of age as metallic interconnects, flexible substrates, insulators, and semiconductors in all-plastic electronics. The focus of this topical review will be on organic light-emitting devices with a discussion of the most recent developments in electronic devices.PACS Nos.: 85.60Jb, 78.60Fi, 78.55Kz, 78.66Qn, 73.61Ph, 72.80Le

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Chirality, Gelation Ability and Crystal Structure: Together or Apart? Alkyl Phenyl Ethers of Glycerol as Simple LMWGs

Symmetry ◽

10.3390/sym13040732 ◽

2021 ◽

Vol 13 (4) ◽

pp. 732

Author(s):

Alexander A. Bredikhin ◽

Aidar T. Gubaidullin ◽

Zemfira A. Bredikhina ◽

Robert R. Fayzullin ◽

Olga A. Lodochnikova

Keyword(s):

Self Assembly ◽

Chiral Recognition ◽

Soft Materials ◽

Gelling Agent ◽

Low Molecular Weight ◽

X Ray Diffraction ◽

X Ray ◽

Different Types ◽

Low Molecular Weight Gelators ◽

Phenyl Ethers

Chiral recognition plays an important role in the self-assembly of soft materials, in particular supramolecular organogels formed by low molecular weight gelators (LMWGs). Out of 14 pairs of the studied racemic and enantiopure samples of alkyl-substituted phenyl ethers of glycerol, only eight enantiopure diols form the stable gels in nonane. The formation of gels from solutions was studied by polarimetry, and their degradation with the formation of xerogels was studied by the PXRD method. The revealed crystalline characteristics of all studied xerogels corresponded to those for crystalline samples of the parent gelators. In addition to those previously investigated, crystalline samples of enantiopure para-n-alkylphenyl glycerol ethers [alkyl = pentyl (5), hexyl (6), heptyl (7), octyl (8), nonyl (9)] and racemic 3-(3,5-dimethylphenoxy)propane-1,2-diol (rac-14) have been examined by single crystal X-ray diffraction analysis. Among 22 samples of compounds 1-14 studied by SC-XRD, seven different types of supramolecular motifs are identified, of which only two are realized in crystals of supramolecular gelators. An attempt was made to relate the ability to gel formation with the characteristics of the supramolecular motif of a potential gelling agent, and the frequency of formation of the motif, required for gelation, with the chiral characteristics of the sample.

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Toward Experimental Evolution with Giant Vesicles

Life ◽

10.3390/life8040053 ◽

2018 ◽

Vol 8 (4) ◽

pp. 53 ◽

Cited By ~ 6

Author(s):

Hironori Sugiyama ◽

Taro Toyota

Keyword(s):

Chemical Evolution ◽

Self Assembly ◽

Experimental Evolution ◽

Microfluidic Devices ◽

Future Perspective ◽

Cell Models ◽

Giant Vesicles ◽

Chemical Models ◽

Recent Developments ◽

Oil Emulsions

Experimental evolution in chemical models of cells could reveal the fundamental mechanisms of cells today. Various chemical cell models, water-in-oil emulsions, oil-on-water droplets, and vesicles have been constructed in order to conduct research on experimental evolution. In this review, firstly, recent studies with these candidate models are introduced and discussed with regards to the two hierarchical directions of experimental evolution (chemical evolution and evolution of a molecular self-assembly). Secondly, we suggest giant vesicles (GVs), which have diameters larger than 1 µm, as promising chemical cell models for studying experimental evolution. Thirdly, since technical difficulties still exist in conventional GV experiments, recent developments of microfluidic devices to deal with GVs are reviewed with regards to the realization of open-ended evolution in GVs. Finally, as a future perspective, we link the concept of messy chemistry to the promising, unexplored direction of experimental evolution in GVs.

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Behavior of a smart one-way micro-valve considering fluid–structure interaction

Journal of Intelligent Material Systems and Structures ◽

10.1177/1045389x18803445 ◽

2018 ◽

Vol 29 (20) ◽

pp. 3960-3971 ◽

Cited By ~ 5

Author(s):

H Mazaheri ◽

AH Namdar ◽

A Amiri

Keyword(s):

Interaction Effect ◽

Fluid Structure Interaction ◽

Pressure Head ◽

Soft Materials ◽

Crosslinking Density ◽

Operational Parameters ◽

Sensors And Actuators ◽

Fluid Structure ◽

Structure Interaction ◽

Different Temperatures

Smart hydrogels are soft materials which can be applied in sensors and actuators especially in microfluidics in which the fluid–structure interaction is important. In this work, first, the behavior of a one-way hydrogel micro-valve is investigated by considering the fluid–structure interaction effect for a specified geometry of the micro-valve. Second, both the fluid–structure interaction and non-fluid–structure interaction simulations are conducted to study the fluid flow effect on the operational parameters of the micro-valve. The obtained results show that the fluid–structure interaction effects are important and have a considerable influence on the micro-valve parameters especially on its closing temperature. Thereafter, a precise study on the micro-valve is executed by considering the micro-valve operational parameters such as inlet pressure, head size, crosslinking density, and breaking pressure at different temperatures. The results show the importance of considering the fluid–structure interaction effect in the design of these devices.

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Geometric Effect for Biological Reactors and Biological Fluids

Bioengineering ◽

10.3390/bioengineering5040110 ◽

2018 ◽

Vol 5 (4) ◽

pp. 110 ◽

Cited By ~ 2

Author(s):

Kazusa Beppu ◽

Ziane Izri ◽

Yusuke Maeda ◽

Ryota Sakamoto

Keyword(s):

Biological Fluids ◽

Biological Systems ◽

Self Organization ◽

Active Matter ◽

Confined Space ◽

Self Organized ◽

Motile Cells ◽

Recent Developments ◽

A Cell

As expressed “God made the bulk; the surface was invented by the devil” by W. Pauli, the surface has remarkable properties because broken symmetry in surface alters the material properties. In biological systems, the smallest functional and structural unit, which has a functional bulk space enclosed by a thin interface, is a cell. Cells contain inner cytosolic soup in which genetic information stored in DNA can be expressed through transcription (TX) and translation (TL). The exploration of cell-sized confinement has been recently investigated by using micron-scale droplets and microfluidic devices. In the first part of this review article, we describe recent developments of cell-free bioreactors where bacterial TX-TL machinery and DNA are encapsulated in these cell-sized compartments. Since synthetic biology and microfluidics meet toward the bottom-up assembly of cell-free bioreactors, the interplay between cellular geometry and TX-TL advances better control of biological structure and dynamics in vitro system. Furthermore, biological systems that show self-organization in confined space are not limited to a single cell, but are also involved in the collective behavior of motile cells, named active matter. In the second part, we describe recent studies where collectively ordered patterns of active matter, from bacterial suspensions to active cytoskeleton, are self-organized. Since geometry and topology are vital concepts to understand the ordered phase of active matter, a microfluidic device with designed compartments allows one to explore geometric principles behind self-organization across the molecular scale to cellular scale. Finally, we discuss the future perspectives of a microfluidic approach to explore the further understanding of biological systems from geometric and topological aspects.

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