Smart Blending: Functional Fine-Scale Structures Formed by Intelligent Agitations in Multi-Component Melts

Volume 2: Symposia, Parts A, B, and C ◽

10.1115/fedsm2003-45051 ◽

2003 ◽

Cited By ~ 1

Author(s):

D. A. Zumbrunnen

Keyword(s):

Mechanical Properties ◽

Fluid Mechanics ◽

Layer Structure ◽

Chaotic Advection ◽

Fine Scale ◽

Electrically Conducting ◽

Molecular Scale ◽

Small Feature ◽

Scale Structures

In viscous melts, turbulence often does not arise. Consequently, opportunities exist for controllably organizing melt components into functional structures that can have very small feature sizes. In this paper, concepts and results of smart blending are described. Smart blending entails the controllable development in situ of a variety of fine-scale structures in the melt by intelligent agitations. Once formed, structures may be useful in the melt or may be captured in applicable products by extrusion and solidification. Chaotic advection is an enabling recent sub-field of fluid mechanics for smart blending since it provides a means to stretch and fold melt domains and evolve a multi-layer structure leading to derivative arrangements, or indirectly manipulate solid additives. Applications include the production of plastics with enhanced mechanical properties, electrically conducting plastics and glasses, low permeation films, membranes, and nano- and molecular-scale composites.

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Design and preparation of an ultra-high temperature ceramic by in-situ introduction of Zr2[Al(Si)]4C5 into ZrB2-SiC: Investigation on the mechanical properties and oxidation behavior

Journal of Advanced Ceramics ◽

10.1007/s40145-021-0493-y ◽

2021 ◽

Author(s):

Lei Yu ◽

Hui Liu ◽

Yaohui Fu ◽

Weijiang Hu ◽

Zhefei Wang ◽

...

Keyword(s):

Mechanical Properties ◽

Layer Structure ◽

Synergistic Effects ◽

High Hardness ◽

Matrix Composites ◽

Pull Out ◽

Parabolic Law ◽

Formation And Evolution ◽

First Time

AbstractNovel ZrB2-matrix composites were designed and prepared by in-situ introducing SiC and Zr2[Al(Si)]4C5 simultaneously for the first time. The obtained composites were dense and showed good mechanical properties, especially the strength and toughness, 706 MPa and 7.33 MPa·m1/2, respectively, coupled with high hardness of 21.3 GPa, and stiffness of 452 GPa. SiC and Zr2[Al(Si)]4C5 constituted a reinforcing system with synergistic effects including grain refinement, grain pull-out as well as crack branching, bridging, and deflection. Besides, the oxidation results of the composites showed that the oxidation kinetics followed the parabolic law at 1600 °C, and the oxidation rate constants increased with the increase of Zr2[Al(Si)]4C5 content. The formation and evolution model of the oxidation structure was also investigated, and the oxide scale of the composite exhibited a three-layer structure.

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Particle Transport via Three-Dimensional Chaotic Advection to Produce Electrically Conducting Plastics With Powder Additives

10.1115/imece1999-1072 ◽

1999 ◽

Author(s):

R. I. Danescu ◽

D. A. Zumbrunnen

Keyword(s):

Carbon Black ◽

Three Dimensional ◽

Chaotic Advection ◽

Chaotic Mixing ◽

Complex Structures ◽

Two Dimensional ◽

Electrical Measurements ◽

Electrically Conducting ◽

Scale Structures ◽

Large Clusters

Abstract Extended micron-scale structures were produced in thermoplastic melts from initially large clusters of conducting carbon black particles transported by three-dimensional chaotic mixing. The structures formed networks that were captured by solidification and rendered the composite materials electrically conducting. A systematic study was carried out to assess the influence of key parameters and relate the electrical properties to the microstructures. Micrographs showed complex structures exhibiting patterns characteristic of chaos. Electrical measurements indicated that conductivity was achieved at carbon black concentrations significantly lower than achievable by common mixing methods, and lower than reported recently for two-dimensional chaotic mixing.

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Recent progress in the study of fine-scale physical-biological coupling in the Mediterranean Sea.

10.5194/egusphere-egu21-7133 ◽

2021 ◽

Author(s):

Roxane Tzortzis ◽

Andrea M. Doglioli ◽

Stéphanie Barrillon ◽

Anne A. Petrenko ◽

Francesco d'Ovidio ◽

...

Keyword(s):

Mediterranean Sea ◽

Temporal Frequency ◽

Phytoplankton Growth ◽

Coupling Mechanism ◽

Fine Scale ◽

Biological Coupling ◽

The Future ◽

Scale Structures ◽

The Mediterranean

The fine scales are defined here as oceanic dynamical features (eddies, fronts and filaments) generally induced by mesoscale interactions and frontogenesis, and often associated with intense vertical exchanges. These processes are characterized by horizontal scales of 1&#8211;10 km with a relatively short lifetime of days/weeks to months. This temporal scale is similar to that of many biological processes, such as, phytoplankton growth, suggesting a physical and biological coupling. Numerical simulations and satellite observations have allowed the characterization of this regime highlighting the role played by these fine scales on structuring the phytoplankton community. To better understand this coupling mechanism, physical and biological in situ measurements are necessary. However, the observations of fine scales remains challenging due to the difficulties of sampling at high spatio-temporal frequency (~km ~daily). Over the past few years, the Mediterranean Sea has become a lab for developing fine scale in situ strategies. Indeed, a series of campaigns using a satellite based adaptative and Lagrangian strategy coupled with a high-resolution physical-biological sampling, have been performed in order to follow and describe fine scale structures. Following this strategy, the PROTEVSMED-SWOT 2018 cruise has been leaded in the South of the Balearic Islands, with a particular attention to correlate the Lagrangian sampling with the temporal phytoplankton growth, in order to reconstruct the phytoplankton diurnal cycle. Multidisciplinary in situ sensors have allowed to identify a frontal area with a dynamic vertical circulation. Furthermore, the presence of two Atlantic waters, at different stages of mixing associated with various abundances of several phytoplankton groups, corroborated that fine scales must be dynamical barriers to transport, as previous modeling studies have proposed. In order to better understand fine scale mechanisms, the Protevs Gibraltar cruise was performed in the Strait of Gibraltar in October 2020. This region of study is characterized by an important exchange of Mediterranean and Atlantic waters, and also by an intense circulation that generates energetic processes, which make it a favorable place for the formation of fine scale structures. The new knowledge acquired with these studies paves the way to the future BIOSWOT-Med campaign planned for 2022 in the western Mediterranean Sea under the future SWOT satellite crossover tracks.

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Design of the Observing System Simulation Experiments with multi-platform in situ data and impact on fine- scale structures

10.3289/eurosea_d2.1 ◽

2020 ◽

Author(s):

Barbara Barcelo-Llull ◽

Ananda Pascual ◽

Eugenio Cutolo ◽

Ronan Fablet ◽

Florent Gasparin ◽

...

Keyword(s):

System Simulation ◽

Satellite Observations ◽

Fine Scale ◽

Simulation Experiments ◽

Work Plan ◽

In Situ Data ◽

Scale Structures

This report presents the work plan of the Task 2.3: Observing System Simulation Experiments: impact of multi-platform observations for the validation of satellite observations

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In situ assembly using a continuous chaotic advection blending process of electrically conducting networks in carbon black-thermoplastic extrusions

Chemical Engineering Science ◽

10.1016/j.ces.2004.10.043 ◽

2005 ◽

Vol 60 (8-9) ◽

pp. 2459-2467 ◽

Cited By ~ 10

Author(s):

V.A. Chougule ◽

D.A. Zumbrunnen

Keyword(s):

Carbon Black ◽

Chaotic Advection ◽

Electrically Conducting ◽

Conducting Networks ◽

Blending Process

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Dynamics of Nanoparticle Chain Aggregates of Carbon Under Tension

MRS Proceedings ◽

10.1557/proc-778-u4.4 ◽

2003 ◽

Vol 778 ◽

Author(s):

Rajdip Bandyopadhyaya ◽

Weizhi Rong ◽

Yong J. Suh ◽

Sheldon K. Friedlander

Keyword(s):

Mechanical Properties ◽

Carbon Black ◽

Polymer Film ◽

Elastic Behavior ◽

Small Strains ◽

Transmission Electron ◽

Chain Aggregates ◽

Nanoparticle Chains ◽

Reinforcing Filler

AbstractCarbon black in the form of nanoparticle chains is used as a reinforcing filler in elastomers. However, the dynamics of the filler particles under tension and their role in the improvement of the mechanical properties of rubber are not well understood. We have studied experimentally the dynamics of isolated nanoparticle chain aggregates (NCAs) of carbon made by laser ablation, and also that of carbon black embedded in a polymer film. In situ studies of stretching and contraction of such chains in the transmission electron microscope (TEM) were conducted under different maximum values of strain. Stretching causes initially folded NCA to reorganize into a straight, taut configuration. Further stretching leads to either plastic deformation and breakage (at 37.4% strain) or to a partial elastic behavior of the chain at small strains (e.g. 2.3% strain). For all cases the chains were very flexible under tension. Similar reorientation and stretching was observed for carbon black chains embedded in a polymer film. Such flexible and elastic nature of NCAs point towards a possible mechanism of reinforcement of rubber by carbon black fillers.

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