Electrowetting and droplet impalement experiments on superhydrophobic multiscale structures

2010 ◽  
Vol 146 ◽  
pp. 125 ◽  
Author(s):  
F. Lapierre ◽  
P. Brunet ◽  
Y. Coffinier ◽  
V. Thomy ◽  
R. Blossey ◽  
...  
Keyword(s):  
Multiscale Structures

ADDITIVE MANUFACTURING OF HIGH-LOADING POLYMER NANOCOMPOSITES WITH MULTISCALE ALIGNMENT

2021 ◽  
Author(s):  
SOYEON PARK ◽  
KUN (KELVIN) FU
Keyword(s):  
Additive Manufacturing ◽  
Polymer Nanocomposites ◽  
High Performance ◽  
Energy Storage Devices ◽  
Storage Devices ◽  
High Productivity ◽  
Macro Scale ◽  
The Matrix ◽  
Multiscale Structures ◽  
Printing Direction

Polymer nanocomposites have advantages in mechanical, electrical, and optical properties compared to individual components. These unique properties of the nanocomposites have attracted attention in many applications, including electronics, robotics, biomedical fields, automotive industries. To achieve their high performance, it is crucial to control the orientation of nanomaterials within the polymer matrix. For example, the electric conductivity will be maximized in the ordered direction of conductive nanomaterials such as graphene and carbon nanotubes (CNTs). Conventional fabrication methods are commonly used to obtain polymer nanocomposites with the controlled alignment of nanomaterials using electric or magnetic fields, fluid flow, and shear forces. Such approaches may be complex in preparing a manufacturing system, have low fabrication rate, and even limited structure scalability and complexity required for customized functional products. Recently, additive manufacturing (AM), also called 3D printing, has been developed as a major fabrication technology for nanocomposites with aligned reinforcements. AM has the ability to control the orientation of nanoparticles and offers a great way to produce the composites with cost-efficiency, high productivity, scalability, and design flexibility. Herein, we propose a manufacturing process using AM for the architected structure of polymer nanocomposites with oriented nanomaterials using a polylactic acid polymer as the matrix and graphite and CNTs as fillers. AM can achieve the aligned orientation of the nanofillers along the printing direction. Thus, it enables the fabrication of multifunctional nanocomposites with complex shapes and higher precision, from micron to macro scale. This method will offer great opportunities in the advanced applications that require complex multiscale structures such as energy storage devices (e.g., batteries and supercapacitors) and structural electronic devices (e.g., circuits and sensors).

Self-organized multiscale structures in thermally relativistic electron-positron-ion plasmas

2021 ◽  
Author(s):  
Usman Shazad ◽  
Shafa Ullah ◽  
M. Iqbal
Keyword(s):  
The Self ◽  
Magnetized Plasma ◽  
Complex Conjugate ◽  
Dynamo Theory ◽  
Relativistic Plasmas ◽  
Self Organized ◽  
Electron Positron ◽  
Relativistic Temperature ◽  
Multiscale Structures ◽  
The Impact

Abstract The self-organization of a thermally relativistic magnetized plasma comprising of electrons, positrons and static ions is investigated. The self-organized state is found to be the superposition of three distinct Beltrami fields known as triple Beltrami (TB) state. In general, the eigenvalues associated with the multiscale self-organized vortices may be a pair of complex conjugate and real one. It is shown that all the eigenvalues become real when thermal energy increases or the positron density decreases. The impact of relativistic temperature and positron density on the formation of self-organized structures is investigated. The self-organized field and flow vortices may vary simultaneously on vastly different length scales. The disparate variation of self-organized vortices is important in the context of dynamo theory. The present work is useful to study the formation of multiscale vortices and dynamo mechanisms in multi-species thermally relativistic plasmas.

scholarly journals Multiscale structures and noise in magnetized plasmas line-tied at conducting surfaces

2019 ◽  
Vol 85 (2) ◽  
Author(s):  
A. B. Hassam ◽  
Yi-Min Huang
Keyword(s):  
Magnetic Fields ◽  
Boundary Conditions ◽  
Numerical Simulations ◽  
Magnetized Plasma ◽  
Long Wavelength ◽  
Numerical Noise ◽  
Long Time ◽  
Multiscale Structures ◽  
Ideal Magnetohydrodynamic ◽  
Numerical And Analytical Methods

In magnetized plasma situations where magnetic fields intersect massive conducting boundaries, ‘line-tied’ boundary conditions are often used, analytically and in numerical simulations. For ideal magnetohydrodynamic (MHD) plasmas, these conditions are arrived at given the relatively long time scales for magnetic fields penetrating resistively into good conductors. Under line-tied boundary conditions, numerical simulations often exhibit what could be construed as numerical ‘noise’ emanating from the boundaries. We show here that this ‘noise’ is real. By combining numerical and analytical methods, we highlight the existence of sharp spatial structures near the conductors and confirm the appearance of short wavelength structures riding on long wavelength modes. We conclude that, for numerical fidelity, the short multiscale structures need to be resolved. Generally, the short structure widths scale as the square root of the plasma $\unicode[STIX]{x1D6FD}$.

Fabrication of Custom Pattern Reinforced AZ31 Multilayer Composite Using Ultrasonic Spray Deposition

2016 ◽  
Author(s):  
Mina Bastwros ◽  
Gap-Yong Kim
Keyword(s):  
Spray Deposition ◽  
Matrix Material ◽  
Multilayer Composite ◽  
Nano Structure ◽  
Nanoscale Structures ◽  
Punch Test ◽  
Ultrasonic Spray ◽  
The Matrix ◽  
Multiscale Structures ◽  
Micro Patterns

Mimicking the unique hierarchical, multiscale structures of natural biological materials is a promising approach to create novel materials with outstanding properties. One of the challenges, however, is the lack of scalable fabrication methods capable of making such complex structures. In this study, a multilayer nanocomposite has been synthesized by incorporating an ultrasonic spray deposition technique. The spray deposition system was used to deposit nanoparticles on substrate foils, which were consolidated to synthesize the multilayer composite. A patterned mask was used to create micro-patterns with nanoscale structures. A magnesium alloy, AZ31, foils were used as the matrix material. A mixture of nano-silicon carbide (nano-SiC) and aluminum alloy, Al6061, particles was used as the reinforcement phase in the deposited patterns. A three point bend test and a small punch test were carried out to evaluate the mechanical properties. A multilayer composite consisting of circular micro-patterns with SiC nano-structure was successfully created. The patterned composite showed an enhancement in the flexural yield strength and the flexural ultimate strength of 43% and 30% respectively, compared with the uniform multilayer composite without the patterns.

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