Large‐scale Micropillar 3D Patterning with High‐aspect Ratio Using a Theta‐pipette

The flow behavior and heat transfer were measured in a large scale, high aspect ratio, turbine blade rib-roughened internal cooling channel. The ribs, installed on one wall, were inclined at 90 deg with respect to the main flow direction and generated a blockage of 20%. The rib corners were rounded to take into account manufacturing aspects. The bulk flow Reynolds number was 20,000. Pressure drop and velocity measurements were first conducted. Liquid crystal thermography was applied to quantify the heat transfer, not only along the ribbed and the smooth opposite walls but also on the rib itself. Numerical simulations were conducted with two flow solvers, IGG/FINE (Numeca) and MSD (ONERA) and compared with measurements. They also supported the analysis of the flow behavior. The influence of round-corner versus sharp edge ribs was numerically evaluated with IGG/FINE.

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Scalable Production of Monodisperse Functional Microspheres by Multilayer Parallelization of High Aspect Ratio Microfluidic Channels

Micromachines ◽

10.3390/mi10090592 ◽

2019 ◽

Vol 10 (9) ◽

pp. 592 ◽

Cited By ~ 3

Author(s):

Casper Ho Yin Chung ◽

Binbin Cui ◽

Ruyuan Song ◽

Xin Liu ◽

Xiaonan Xu ◽

...

Keyword(s):

Aspect Ratio ◽

High Aspect Ratio ◽

Large Scale ◽

Scale Up ◽

Functional Materials ◽

Droplet Microfluidics ◽

Microfluidic Channels ◽

Layer By Layer ◽

Precise Control ◽

Wide Range

Droplet microfluidics enables the generation of highly uniform emulsions with excellent stability, precise control over droplet volume, and morphology, which offer superior platforms over conventional technologies for material synthesis and biological assays. However, it remains a challenge to scale up the production of the microfluidic devices due to their complicated geometry and long-term reliability. In this study, we present a high-throughput droplet generator by parallelization of high aspect ratio rectangular structures, which enables facile and scalable generation of uniform droplets without the need to precisely control external flow conditions. A multilayer device is formed by stacking layer-by-layer of the polydimethylsiloxane (PDMS) replica patterned with parallelized generators. By feeding the sample fluid into the device immersed in the carrying fluid, we used the multilayer device with 1200 parallelized generators to generate monodisperse droplets (~45 μm in diameter with a coefficient of variation <3%) at a frequency of 25 kHz. We demonstrate this approach is versatile for a wide range of materials by synthesis of polyacrylamide hydrogel and Poly (l-lactide-co-glycolide) (PLGA) through water-in-oil (W/O) and oil-in-water (O/W) emulsion templates, respectively. The combined scalability and robustness of such droplet emulsion technology is promising for production of monodisperse functional materials for large-scale applications.

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Ultra-high aspect ratio functional nanoporous silicon via nucleated catalysts

RSC Advances ◽

10.1039/c7ra00562h ◽

2017 ◽

Vol 7 (19) ◽

pp. 11537-11542 ◽

Cited By ~ 6

Author(s):

Jatin J. Patil ◽

Brendan D. Smith ◽

Jeffrey C. Grossman

Keyword(s):

Aspect Ratio ◽

High Aspect Ratio ◽

Large Scale ◽

Nanoporous Silicon

Large scale, sub-10 nm high aspect ratio nanoporous silicon is fabricatedviascalable sputtering and a solution-based process.

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Facile Fabrication of Electrohydrodynamic Micro-/Nanostructures with High Aspect Ratio of a Conducting Polymer for Large-Scale Superhydrophilic/Superhydrophobic Surfaces

Macromolecular Materials and Engineering ◽

10.1002/mame.201700361 ◽

2017 ◽

Vol 303 (2) ◽

pp. 1700361 ◽

Cited By ~ 5

Author(s):

Guowei Lv ◽

Yuhang Liu ◽

Jinyou Shao ◽

Hongmiao Tian ◽

Demei Yu

Keyword(s):

Aspect Ratio ◽

Conducting Polymer ◽

High Aspect Ratio ◽

Large Scale ◽

Superhydrophobic Surfaces ◽

Facile Fabrication

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The origin and 3D architecture of a km-scale deep-water scour-fill: example from the Skoorsteenberg Fm., Karoo Basin, South Africa

10.31223/x59p6c ◽

2021 ◽

Author(s):

Larissa Hansen ◽

Rachel Healy ◽

Luz Gomis Cartesio ◽

David Lee ◽

David Hodgson ◽

...

Keyword(s):

South Africa ◽

Aspect Ratio ◽

High Aspect Ratio ◽

Large Scale ◽

Sedimentary Facies ◽

Depositional Environments ◽

Sediment Delivery ◽

Marine Systems ◽

Karoo Basin ◽

Erosion Surface

Scours, and scour fields, are common features on the modern seafloor of deep-marine systems, particularly downstream of submarine channels, and in channel-lobe-transitions-zones. High-resolution images of the seafloor have improved the documentation of the large scale, coalescence, and distribution of these scours in deep-marine systems. However, their scale and high aspect ratio mean they can be challenging to identify in outcrop. Here, we document a large-scale, composite erosion surface from the exhumed deep-marine stratigraphy of Unit 5 from the Permian Karoo Basin succession in South Africa, which is interpreted to be present at the end of a submarine channel.This study utilizes 24 sedimentary logs, 2 cored boreholes, and extensive palaeocurrent and thickness data across a 126 km2 study area. Sedimentary facies analysis, thickness variations and correlation panels allowed identification of a lower heterolithic-dominated part (up to 70 m thick) and an upper sandstone-dominated part (10-40 m thick) separated by an extensive erosion surface. The lower part comprises heterolithics with abundant current and sinusoidal ripples, which due to palaeocurrents, thickness trends and adjacent depositional environments is interpreted as the aggradational lobe complex fringes. The base of the upper part comprises 2-3 medium-bedded sandstone beds interpreted as precursor lobes cut by a 3-4 km wide, 1-2 km long, and up to 28 m deep, high aspect ratio (1:100) composite scour surface. The abrupt change from heterolithics to thick-bedded sandstones marks the establishment of a new sediment delivery system, which may have been triggered by an updip channel avulsion. The composite scour and subsequent sandstone fill support a change from erosion- and bypass-dominated flows to depositional flows, which might reflect increasingly sand-rich flows as a new sediment route matured. This study provides a unique outcrop example with 3D stratigraphic control of the record of a new sediment conduit, and development and fill of a large-scale composite scour surface at the channel mouth, providing a rare insight into how scours imaged on seafloor data can be preserved in the rock record.

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