scholarly journals Self-template–assisted micro-phase segregation in blended liquid-crystalline block copolymers films toward three-dimensional structures

2020 ◽  
Vol 117 (35) ◽  
pp. 21070-21078
Author(s):  
Yusuke Hibi ◽  
Yuki Oguchi ◽  
Yuta Shimizu ◽  
Kayoko Hashimoto ◽  
Katsuya Kondo ◽  
...  
Keyword(s):  
Liquid Crystalline ◽  
Three Dimensional ◽  
Phase Segregation ◽  
Material Design ◽  
The Other ◽  
Cooling Process ◽  
Water Separation ◽  
Practical Applications ◽  
Out Of Plane ◽  
Fundamental Research

In-plane mesopatterns derived from block-copolymer (BCP) micro-phase segregation in thin films have attracted much interest in practical applications as well as fundamental research programs. However, phase segregation along the film-normal direction has been less studied. Here, we describe a strategy to concurrently, yet independently, control in-plane micro-phase and out-of-plane macro-phase segregation in multiblended films composed of liquid-crystalline BCPs (LCBCPs), affording spontaneously layered three-dimensional (3D) mesostructures. This strategy relies on sequential liquid crystallization during the cooling process in thermal annealing as follows. The constituent LCBCP with the highest isotropic-transition temperature (Tiso) first liquid-crystallizes and segregates from the other LCBCP mixture remaining in isotropic states to form a noncontaminated layer at the top surface. This preformed LCBCP layer preserves its inherent in-plane pattern and acts as a template guiding the subsequent micro-phase segregations of the other low-TisoLCBCPs underneath. This self-template–assisted micro-phase segregation (STAMPS) readily provides 3D mesostructures, the potential toward rational material design of which is also demonstrated in water-separation applications.

Correlation of Patellar Tracking Pattern With Trochlear and Retropatellar Surface Topographies

2000 ◽  
Vol 122 (6) ◽  
pp. 652-660 ◽  
Author(s):  
A. M. Ahmed ◽  
N. A. Duncan
Keyword(s):  
Three Dimensional ◽  
Knee Extension ◽  
The Other ◽  
Lateral Direction ◽  
Dial Gage ◽  
Passive Restraint ◽  
Out Of Plane ◽  
Fresh Frozen ◽  
Six Degree Of Freedom ◽  
Anterior Posterior

The study was aimed to test the hypothesis that in the knee extension range 100 to 30 deg, the patellar “out-of-plane” tracking pattern is controlled by the passive restraint provided by the topographic interaction of the patellofemoral contacting surfaces. The out-of-plane tracking pattern, i.e., the pattern of patellar displacements not in the plane of knee extension/flexion, consists of translation in the medial–lateral direction, and rotations about the anterior–posterior axis (spin) and the proximal–distal axis (tilt). Using 15 fresh-frozen knees subjected to extensor moment magnitudes comparable to those in the “static-lifting” activity (foot-ground reaction=334 N), the patellar displacements were measured using a calibrated six-degree-of-freedom electromechanical goniometer. The topographies of the trochlear and retropatellar surfaces were then measured using a calibrated traveling dial-gage arrangement and the same coordinate system used for the displacement measurements. Three indices were defined to quantify particular natural features of the three-dimensional topographies that are expected to control the patellar displacements. Correlation of the indices with their corresponding displacements showed that topographic interaction was significant in the control of all three displacements. However, for patellar spin, unlike for the other two displacements, the direction of the active quadriceps tension vector was also a significant controlling factor. Patellar medial–lateral translation was found to be controlled dominantly by the trochlear topography, while retropatellar topography also had a significant role in the control of the other two displacements. [S0148-0731(00)01406-0]

scholarly journals Microdroplet-guided intercalation and deterministic delamination towards intelligent rolling origami

2019 ◽  
Vol 10 (1) ◽  
Author(s):  
Borui Xu ◽  
Xinyuan Zhang ◽  
Ziao Tian ◽  
Di Han ◽  
Xingce Fan ◽  
...  
Keyword(s):  
Low Cost ◽  
Rolling Direction ◽  
Three Dimensional ◽  
Van Der Waals Interaction ◽  
Creative Design ◽  
General Strategy ◽  
Practical Applications ◽  
On Demand ◽  
Vapor Sensing ◽  
Fundamental Research

Abstract Three-dimensional microstructures fabricated by origami, including folding, rolling and buckling, gain great interests in mechanics, optics and electronics. We propose a general strategy on on-demand and spontaneous rolling origami for artificial microstructures aiming at massive and intelligent production. Deposited nanomembranes are rolled-up in great amount triggered by the intercalation of tiny droplet, taking advantage of a creative design of van der Waals interaction with substrate. The rolling of nanomembranes delaminated by liquid permits a wide choice in materials as well as precise manipulation in rolling direction by controlling the motion of microdroplet, resulting in intelligent construction of rolling microstructures with designable geometries. Moreover, this liquid-triggered delamination phenomenon and constructed microstructures are demonstrated in the applications among vapor sensing, microresonators, micromotors, and microactuators. This investigation offers a simple, massive, low-cost, versatile and designable construction of rolling microstructures for fundamental research and practical applications.

“Seeing” the Resonant SPP Modes Confined in Metal Nanocavity via Cathodoluminescne Spectroscopy

2014 ◽  
Vol 1659 ◽  
pp. 83-94
Author(s):  
Liu Chuanpu ◽  
Zhu Xinli ◽  
Zhang Jiasen ◽  
Xu Jun ◽  
Yu Dapeng
Keyword(s):  
Surface Plasmon ◽  
Surface Plasmon Polaritons ◽  
Strong Field ◽  
Three Dimensional ◽  
Metal Nanostructures ◽  
Feature Size ◽  
Practical Applications ◽  
Plane Field ◽  
Out Of Plane ◽  
Plasmon Polaritons

ABSTRACT:Surface plasmon polaritons (SPPs), which are coupled excitations of electrons bound to a metal-dielectric interface, show great potential for application in future nanoscale photonic systems due to the strong field confinement at the nanoscale, intensive local field enhancement, and interplay between strongly localized and propagating SPPs. The fabrication of sufficiently smooth metal surface with nanoscale feature size is crucial for SPPs to have practical applications. A template stripping (ST) method combined with PMMA as a template was successfully developed to create extraordinarily smooth metal nanostructures with a desirable feature size and morphology for plasmonics and metamaterials. The advantages of this method, including the high resolution, precipitous top-to bottom profile with a high aspect ratio, and three-dimensional characteristics, make it very suitable for the fabrication of plasmonic structures. By using this ST method, boxing ring-shaped nanocavities have been fabricated and the confined modes of surface plasmon polaritons in these nanocavities have been investigated and imaged by using cathodoluminescence (CL) spectroscopy, which has been turned out to be a powerful means to characterize the resonant SPPs modes confined in metal nanocavities [1∼5] . The mode of the out-of-plane field components of surface plasmon polaritons dominates the experimental mode patterns, indicating that the electron beam locally excites the out-of-plane field component of surface plasmon polaritons. Quality factors can be directly acquired from the spectra induced by the ultrasmooth surface of the cavity and the high reflectivity of the silver (Ag) reflectors. Because of its three-dimensional confined characteristics and the omnidirectional reflectors, the nanocavity exhibits a small modal volume, small total volume, rich resonant modes, and flexibility in mode control. Numerous applications, such as plasmonic filter, nanolaser, and efficient light-emitting devices, can be expected to arise from these developments.

scholarly journals Roadmap for advanced aqueous batteries: From design of materials to applications

2020 ◽  
Vol 6 (21) ◽  
pp. eaba4098 ◽  
Author(s):  
Dongliang Chao ◽  
Wanhai Zhou ◽  
Fangxi Xie ◽  
Chao Ye ◽  
Huan Li ◽  
...  
Keyword(s):  
Large Scale ◽  
Cost Effective ◽  
Material Design ◽  
Advanced Materials ◽  
Promising Alternative ◽  
Practical Applications ◽  
Limited Output ◽  
Key Issues ◽  
Fundamental Research ◽  
Aqueous Batteries

Safety concerns about organic media-based batteries are the key public arguments against their widespread usage. Aqueous batteries (ABs), based on water which is environmentally benign, provide a promising alternative for safe, cost-effective, and scalable energy storage, with high power density and tolerance against mishandling. Research interests and achievements in ABs have surged globally in the past 5 years. However, their large-scale application is plagued by the limited output voltage and inadequate energy density. We present the challenges in AB fundamental research, focusing on the design of advanced materials and practical applications of whole devices. Potential interactions of the challenges in different AB systems are established. A critical appraisal of recent advances in ABs is presented for addressing the key issues, with special emphasis on the connection between advanced materials and emerging electrochemistry. Last, we provide a roadmap starting with material design and ending with the commercialization of next-generation reliable ABs.

scholarly journals Postbuckling analyses of frame mesostructures consisting of straight ribbons for mechanically guided three-dimensional assembly

2019 ◽  
Vol 475 (2225) ◽  
pp. 20190012 ◽  
Author(s):  
Yuan Liu ◽  
Zheng Xu ◽  
Keh-Chi Hwang ◽  
Yonggang Huang ◽  
Yihui Zhang
Keyword(s):  
Three Dimensional ◽  
Analytic Solutions ◽  
Finite Element Analyses ◽  
Practical Applications ◽  
Energetic Approach ◽  
Wide Range ◽  
Out Of Plane ◽  
Device Applications ◽  
Theoretical Analyses ◽  
Physical Quantities

Mechanically guided assembly through buckling-induced two-dimensional (2D)-to- three-dimensional (3D) transformation represents a versatile approach to the formation of 3D mesostructures, thanks to the demonstrated applicability to a wide range of length scales (from tens of nanometres to centimetres) and material types (from semiconductors, metals to polymers and ceramics). In many demonstrated examples of device applications, the 2D precursor structures are composed of ribbon-type components, and some of them exhibit frame geometries consisting of multiple straight ribbons. The coupling of bending/twisting deformations among various ribbon components of the frame mesostructures makes the analyses more complicated than the case with a single component, which requires the development of a relevant theory to serve as the basis of design optimization in practical applications. Here, an analytic model of compressive buckling in such frame mesostructures is presented in the framework of energetic approach, taking into account the contributions of spatial bending deformations and twisting deformations. Three different frame geometries are studied, including ‘+’, ‘T' and ‘H' shaped designs. As validated by the experiments and finite-element analyses (FEA), the developed model can predict accurately the assembled 3D configurations during the postbuckling of different precursor shapes. Furthermore, the theoretical analyses provide approximate analytic solutions to some key physical quantities (e.g. the maximum out-of-plane displacements and maximum strains), which can be used as design references in practical applications.

Three-Dimensional Photoreorientation of Self-Organized Azobenzene Chromophores in Liquid Crystalline Polymer Films

1999 ◽  
Vol 559 ◽  
Author(s):  
M. Han ◽  
S. Morino ◽  
K. Ichimura
Keyword(s):  
Absorption Spectroscopy ◽  
Liquid Crystalline Polymer ◽  
Liquid Crystalline ◽  
Critical Role ◽  
Three Dimensional ◽  
Crystalline Polymer ◽  
Infrared Transmission ◽  
Self Organized ◽  
Out Of Plane ◽  
Transmission And Reflection

ABSTRACTPhoto-induced reorientational behavior of films of a liquid crystalline polymer with azobenzene side chains was studied by means of UV-Vis absorption spectroscopy and Fourier transform infrared transmission and reflection-absorption spectroscopy. The incident directions of light for photoisomerization played a critical role in the photocontrol of out-of-plane (three-dimensional) orientation of the azobenzenes in films. Tilted directions of the azobenzene residues were evaluated by using polarized UV-Vis absorption spectra. Photoreoriented states of azobenzene chromophores including photodichroism and tilted alignment were enhanced by successive annealing of photoirradiated films at temperatures close to the glass transition temperature of the polymer.

scholarly journals Bicontinuous Cubic and Hexagonal Columnar Liquid Crystalline Ion-Conductors at Room Temperature in Ion-Doped Dendritic Amphiphiles

Crystals ◽  
2020 ◽  
Vol 10 (3) ◽  
pp. 193
Author(s):  
Thi Huyen Do ◽  
Ho-Joong Kim ◽  
Manh Linh Nguyen ◽  
Byoung-Ki Cho
Keyword(s):  
Liquid Crystalline ◽  
Room Temperature ◽  
Molecular Design ◽  
Three Dimensional ◽  
Impedance Analysis ◽  
Practical Applications ◽  
Alkyl Chains ◽  
Bicontinuous Cubic ◽  
Hexagonal Columnar ◽  
Ion Conductors

A bicontinuous cubic (Cubbi) liquid crystalline (LC) phase consisting of three dimensional (3D) conducting networks is a promising structural platform for ion-conductors. For practical applications using this fascinating LC structure, it is necessary to suppress crystallization at room temperature (RT). Herein, we report the Cubbi structure at RT and the morphology–dependent conduction behavior in ionic samples of a non-crystallizable dendritic amphiphile. In the molecular design, branched alkyl chains were used as an ionophobic part instead of crystallizable linear alkyl chains. Two ionic samples with Cubbi and hexagonal columnar (Colhex) LC phases at RT were prepared by adding different amounts of lithium salt to the amphiphile. Impedance analysis demonstrated that the Cubbi phase contributed to the faster ion-conduction to a larger extent than the Colhex phase due to the 3D ionic networks of the Cubbi phase. In addition, the temperature–dependent impedance and electric modulus data provided information regarding the phase transition from microphase-separated phase to molecularly mixed liquid phase.

Fundamental Research on Development of Liquid Crystalline Micro-Actuator

2012 ◽  
Vol 502 ◽  
pp. 264-268 ◽  
Author(s):  
Chun Bo Liu ◽  
Yan Fang Guan
Keyword(s):  
Liquid Crystal ◽  
Liquid Crystalline ◽  
Twist Angle ◽  
Parallel Plates ◽  
Micro Actuator ◽  
Plane Component ◽  
Out Of Plane ◽  
Calculation Results ◽  
Fundamental Research ◽  
Induced Flow

As a purpose of developing new micro-actuator driven by the liquid crystal flow, transient behaviors of a nematic liquid crystal between two parallel plates are computed with parameter of twist angle. The Frank and Leslie-Ericksen theory were used. When the twist angle is 0 deg, the induced flow is planar, and when the twist angle is not 0 deg, the flow has a out of plane component. The twist angle has little effect to the time characteristics of the flow. In the experiment, the applied voltage of 5 was used, and the results are in agreement with the calculation results.

Three-Dimensional Reconstruction of Two Forms of the Chaperonin GRO EL

1990 ◽  
Vol 48 (1) ◽  
pp. 258-259
Author(s):  
J.L. Carrascosa ◽  
G. Abella ◽  
S. Marco ◽  
M. Muyal ◽  
J.M. Carazo
Keyword(s):  
Three Dimensional ◽  
The Other ◽  
Two Dimensional ◽  
Series Method ◽  
Three Dimensional Reconstruction ◽  
Structural Components ◽  
E Coli ◽  
Dimensional Reconstruction ◽  
Morphogenetic Factors ◽  
Tilt Series

Chaperonins are a class of proteins characterized by their role as morphogenetic factors. They trantsiently interact with the structural components of certain biological aggregates (viruses, enzymes etc), promoting their correct folding, assembly and, eventually transport. The groEL factor from E. coli is a conspicuous member of the chaperonins, as it promotes the assembly and morphogenesis of bacterial oligomers and/viral structures.We have studied groEL-like factors from two different bacteria:E. coli and B.subtilis. These factors share common morphological features , showing two different views: one is 6-fold, while the other shows 7 morphological units. There is also a correlation between the presence of a dominant 6-fold view and the fact of both bacteria been grown at low temperature (32°C), while the 7-fold is the main view at higher temperatures (42°C). As the two-dimensional projections of groEL were difficult to interprete, we studied their three-dimensional reconstruction by the random conical tilt series method from negatively stained particles.

An Efficient Multiple Description Coding for Multi-View Video Based on the Correlation of Spatial Polyphase Transformed Subsequences

2019 ◽  
Vol 63 (5) ◽  
pp. 50401-1-50401-7 ◽  
Author(s):  
Jing Chen ◽  
Jie Liao ◽  
Huanqiang Zeng ◽  
Canhui Cai ◽  
Kai-Kuang Ma
Keyword(s):  
Video Transmission ◽  
Video Sequence ◽  
Three Dimensional ◽  
The Other ◽  
Multiple Description Coding ◽  
Multiple Description ◽  
Prediction Mode ◽  
Gradient Based ◽  
Directional Interpolation ◽  
Description Coding

Abstract For a robust three-dimensional video transmission through error prone channels, an efficient multiple description coding for multi-view video based on the correlation of spatial polyphase transformed subsequences (CSPT_MDC_MVC) is proposed in this article. The input multi-view video sequence is first separated into four subsequences by spatial polyphase transform and then grouped into two descriptions. With the correlation of macroblocks in corresponding subsequence positions, these subsequences should not be coded in completely the same way. In each description, one subsequence is directly coded by the Joint Multi-view Video Coding (JMVC) encoder and the other subsequence is classified into four sets. According to the classification, the indirectly coding subsequence selectively employed the prediction mode and the prediction vector of the counter directly coding subsequence, which reduces the bitrate consumption and the coding complexity of multiple description coding for multi-view video. On the decoder side, the gradient-based directional interpolation is employed to improve the side reconstructed quality. The effectiveness and robustness of the proposed algorithm is verified by experiments in the JMVC coding platform.

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