scholarly journals The long-wavelength geoid from three-dimensional spherical models of thermal and thermochemical mantle convection

2015 ◽  
Vol 120 (6) ◽  
pp. 4572-4596 ◽  
Author(s):  
Xi Liu ◽  
Shijie Zhong
Keyword(s):  
Mantle Convection ◽  
Three Dimensional ◽  
Long Wavelength ◽  
Spherical Models

Three-dimensional spherical models of layered and whole mantle convection

1993 ◽  
Vol 98 (B12) ◽  
pp. 21969-21976 ◽  
Author(s):  
Gary A. Glatzmaier ◽  
Gerald Schubert
Keyword(s):  
Mantle Convection ◽  
Three Dimensional ◽  
Spherical Models

scholarly journals Steady streaming confined between three-dimensional wavy surfaces

2010 ◽  
Vol 657 ◽  
pp. 430-455 ◽  
Author(s):  
ROMAIN GUIBERT ◽  
FRANCK PLOURABOUÉ ◽  
ALAIN BERGEON
Keyword(s):  
Numerical Study ◽  
Second Harmonic ◽  
Three Dimensional ◽  
Womersley Number ◽  
Long Wavelength ◽  
Steady Streaming ◽  
Confined Flow ◽  
Wavy Surfaces ◽  
Harmonic Flow ◽  
Arbitrary Amplitude

We present a theoretical and numerical study of three-dimensional pulsatile confined flow between two rigid horizontal surfaces separated by an average gap h, and having three-dimensional wavy shapes with arbitrary amplitude σh where σ ~ O(1), but long-wavelength variations λ, with h/λ ≪ 1. We are interested in pulsating flows with moderate inertial effect arising from the Reynolds stress due to the cavity non-parallelism. We analyse the inertial steady-streaming and the second harmonic flows in a lubrication approximation. The dependence of the three-dimensional velocity field in the transverse direction is analytically obtained for arbitrary Womersley numbers and possibly overlapping Stokes layers. The horizontal dependence of the flow is solved numerically by computing the first two pressure fields of an asymptotic expansion in the small inertial limit. We study the variations of the flow structure with the amplitude, the channel's wavelength and the Womersley number for various families of three-dimensional channels. The steady-streaming flow field in the horizontal plane exhibits a quadrupolar vortex, the size of which is adjusted to the cavity wavelength. When increasing the wall amplitude, the wavelengths characterizing the channel or the Womersley number, we find higher-order harmonic flow structures, the origin of which can either be inertially driven or geometrically induced. When some of the channel symmetries are broken, a steady-streaming current appears which has a quadratic dependence on the pressure drop, the amplitude of which is linked to the Womersley number.

Tunable luminescence and white light emission of porphyrin-zinc coordination assemblies

2018 ◽  
Vol 22 (09n10) ◽  
pp. 821-830 ◽  
Author(s):  
Zheng Wang ◽  
Jian-Hua Zhang ◽  
Cheng-Yi Zhu ◽  
Shao-Yun Yin ◽  
Mei Pan
Keyword(s):  
White Light ◽  
Light Emission ◽  
Three Dimensional ◽  
White Light Emission ◽  
Molar Ratio ◽  
Excitation Wavelength ◽  
Temperature Dependent ◽  
Long Wavelength ◽  
Linear Formula ◽  
Zinc Coordination

Bipodal ligand 5,15-bis(4-carboxyphenyl) porphyrin (H[Formula: see text]DCPP) was designed and synthesized. By adjusting the molar ratio of H[Formula: see text]DCPP, ancillary ligand 4,4-bipyridine (bpy) and zinc acetate salts, three novel coordination assemblies, namely, zero-dimensional dimeric [Zn[Formula: see text](H[Formula: see text]DCPP)[Formula: see text] ·bpy] ·4H[Formula: see text]O ·4DMF (Zn-D), two-dimensional polymeric {[Zn[Formula: see text](DCPP) ·bpy[Formula: see text] ·H[Formula: see text]O ·DMF[Formula: see text]] ·solvent}[Formula: see text] (Zn-2D), and three-dimensional polymeric [Zn[Formula: see text](DCPP) ·bpy[Formula: see text]][Formula: see text] (Zn-3D) were assembled. Due to the delicate integration of multiple chromophores in the coordination space combining bpy, DCPP and MLCT emissions together, photoluminescence (PL) of the three porphyrin-zinc coordination assemblies differ from each other and color tone is tunable from blue to orange with changes of the excitation wavelength. In particular, white light emission (WLE) can be observed by the excitation of 270 to 290 nm, representing the first examples of single component WLE compounds based on porphyrin ligands. Furthermore, temperature-dependent luminescence results in a linear [Formula: see text]–[Formula: see text] relationship in Zn-2D and Zn-3D assemblies, applicable for long wavelength red-emitting thermometers.

scholarly journals Cooperatively rearranging regions change shape near the mode-coupling crossover for colloidal liquids on a sphere

2020 ◽  
Vol 11 (1) ◽  
Author(s):  
Navneet Singh ◽  
A. K. Sood ◽  
Rajesh Ganapathy
Keyword(s):  
Glass Transition ◽  
Mode Coupling ◽  
Three Dimensional ◽  
Order Theory ◽  
True Nature ◽  
Long Wavelength ◽  
Slowing Down ◽  
First Order Theory ◽  
Colloidal Liquids ◽  
Strong Curvature

Abstract The structure and dynamics of liquids on curved surfaces are often studied through the lens of frustration-based approaches to the glass transition. Competing glass transition theories, however, remain largely untested on such surfaces and moreover, studies hitherto have been entirely theoretical/numerical. Here we carry out single particle-resolved imaging of dynamics of bi-disperse colloidal liquids confined to the surface of a sphere. We find that mode-coupling theory well captures the slowing down of dynamics in the moderate to deeply supercooled regime. Strikingly, the morphology of cooperatively rearranging regions changed from string-like to compact near the mode-coupling crossover—a prediction unique to the random first-order theory of glasses. Further, we find that in the limit of strong curvature, Mermin–Wagner long-wavelength fluctuations are irrelevant and liquids on a sphere behave like three-dimensional liquids. A comparative evaluation of competing mechanisms is thus an essential step towards uncovering the true nature of the glass transition.

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