Synchrotron radiography characterization of the liquid core dynamics in a canonical two-fluid coaxial atomizer

Nano-LiFePO4/C materials were synthesized by two-fluid spray-drying using FePO4·2H2O, LiOH·H2O as raw materials. The morphology, physical and electrochemical properties of the LiFePO4/C were tested and analyzed. The morphology of the synthesis LiFePO4/C was spherical and its aggregated particle size was smaller than 10μm, primary particle size was smaller than 200nm, the tap density of the material up to 1.25g/cm3. The LiFePO4/C had an initial discharge specific capacity of 163.3mAh/g at 0.1C and its specific capacities were 147.7mAh/g and 121.8mAh/g at 1C and 5C, respectively. The initial charge/discharge efficiency reached 96.6%. Under low temperature 253K, the discharge capacity is 59.6% of that at 298K with 0.2C.

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Integration and characterization of SiN nanopores for single-molecule detection in liquid-core ARROW waveguides

10.1117/12.700479 ◽

2007 ◽

Cited By ~ 3

Author(s):

M. I. Rudenko ◽

D. Yin ◽

M. Holmes ◽

A. R. Hawkins ◽

H. Schmidt

Keyword(s):

Single Molecule ◽

Liquid Core ◽

Single Molecule Detection

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Latitudinal libration driven flows in triaxial ellipsoids

Journal of Fluid Mechanics ◽

10.1017/jfm.2015.130 ◽

2015 ◽

Vol 771 ◽

pp. 193-228 ◽

Cited By ~ 13

Author(s):

S. Vantieghem ◽

D. Cébron ◽

J. Noir

Keyword(s):

Numerical Simulations ◽

Equations Of Motion ◽

Liquid Core ◽

Three Dimensional ◽

Base Flow ◽

Upper And Lower Bounds ◽

Earth Planet ◽

Ekman Layers ◽

Core Dynamics ◽

Inertial Instability

Motivated by understanding the liquid core dynamics of tidally deformed planets and moons, we present a study of incompressible flow driven by latitudinal libration within rigid triaxial ellipsoids. We first derive a laminar solution for the inviscid equations of motion under the assumption of uniform vorticity flow. This solution exhibits a resonance if the libration frequency matches the frequency of the spin-over inertial mode. Furthermore, we extend our model by introducing a reduced model of the effect of viscous Ekman layers in the limit of low Ekman number (Noir & Cébron, J. Fluid Mech., vol. 737, 2013, pp. 412–439). This theoretical approach is consistent with the results of Chan et al. (Phys. Earth Planet. Inter., vol. 187, 2011, pp. 404–415) and Zhang et al. (J. Fluid Mech., vol. 692, 2012, pp. 420–445) for spheroidal geometries. Our results are validated against systematic three-dimensional numerical simulations. In the second part of the paper, we present the first linear stability analysis of this uniform vorticity flow. To this end, we adopt different methods (Lifschitz & Hameiri, Phys. Fluids A, vol. 3, 1991, p. 2644; Gledzer & Ponomarev, Acad. Sci., USSR, Izv., Atmos. Ocean. Phys., vol. 13, 1977, pp. 565–569) that allow us to deduce upper and lower bounds for the growth rate of an instability. Our analysis shows that the uniform vorticity base flow is prone to inertial instabilities caused by a parametric resonance mechanism. This is confirmed by a set of direct numerical simulations. Applying our results to planetary settings, we find that neither a spin-over resonance nor an inertial instability can exist within the liquid core of the Moon, Io and Mercury.

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Transport efficiency of metachronal waves in 3D cilium arrays immersed in a two-phase flow

Journal of Fluid Mechanics ◽

10.1017/jfm.2017.352 ◽

2017 ◽

Vol 824 ◽

pp. 931-961 ◽

Cited By ~ 15

Author(s):

S. Chateau ◽

J. Favier ◽

U. D’Ortona ◽

S. Poncet

Keyword(s):

Viscosity Ratio ◽

Coupling Parameter ◽

Immersed Boundary ◽

Two Phase ◽

Epithelial Surface ◽

Transport Efficiency ◽

Fluid Environment ◽

Metachronal Waves ◽

Two Fluid

This work reports the formation and characterization of antipleptic and symplectic metachronal waves in 3D cilium arrays immersed in a two-fluid environment, with a viscosity ratio of 20. A coupled lattice Boltzmann–immersed-boundary solver is used. The periciliary layer is confined between the epithelial surface and the mucus. Its thickness is chosen such that the tips of the cilia can penetrate the mucus. A purely hydrodynamical feedback of the fluid is taken into account and a coupling parameter $\unicode[STIX]{x1D6FC}$ is introduced, which allows tuning of both the direction of the wave propagation and the strength of the fluid feedback. A comparative study of both antipleptic and symplectic waves, mapping a cilium interspacing ranging from 1.67 up to 5 cilium lengths, is performed by imposing metachrony. Antipleptic waves are found to systematically outperform symplectic waves. They are shown to be more efficient for transporting and mixing the fluids, while spending less energy than symplectic, random or synchronized motions.

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Non-monotonic growth and motion of the South Atlantic Anomaly

Earth Planets and Space ◽

10.1186/s40623-021-01356-w ◽

2021 ◽

Vol 73 (1) ◽

Author(s):

Hagay Amit ◽

Filipe Terra-Nova ◽

Maxime Lézin ◽

Ricardo I. Trindade

Keyword(s):

Large Scale ◽

South Atlantic ◽

The South ◽

South Atlantic Anomaly ◽

Societal Issues ◽

Special Events ◽

Core Dynamics ◽

Intensity Changes ◽

The Magnetic Field

AbstractThe South Atlantic Anomaly (SAA) is a region at Earth’s surface where the intensity of the magnetic field is particularly low. Accurate characterization of the SAA is important for both fundamental understanding of core dynamics and the geodynamo as well as societal issues such as the erosion of instruments at surface observatories and onboard spacecrafts. Here, we propose new measures to better characterize the SAA area and center, accounting for surface intensity changes outside the SAA region and shape anisotropy. Applying our characterization to a geomagnetic field model covering the historical era, we find that the SAA area and center are more time dependent, including episodes of steady area, eastward drift and rapid southward drift. We interpret these special events in terms of the secular variation of relevant large-scale geomagnetic flux patches on the core–mantle boundary. Our characterization may be used as a constraint on Earth-like numerical dynamo models.

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