On the Growth Dynamics of Nearly-Locked Grain in the Three-Phase In-Bi-Sn Eutectic System

In vivo tumours are highly heterogeneous entities which often comprise intratumoural regions of hypoxia and widespread necrosis. In this paper, we develop a new three phase model of nutrient-limited, avascular tumour growth to investigate how dead material within the tumour may influence the tumour’s growth dynamics. We model the tumour as a mixture of tumour cells, dead cellular material and extracellular fluid. The model equations are derived using mass and momentum balances for each phase along with appropriate constitutive equations. The tumour cells are viewed as a viscous fluid pressure, while the extracellular fluid phase is viewed as inviscid. The physical properties of the dead material are intermediate between those of the tumour cells and extracellular fluid, and are characterised by three key parameters. Through numerical simulation of the model equations, we reproduce spatial structures and dynamics typical of those associated with the growth of avascular tumour spheroids. We also characterise novel, non-monotonic behaviours which are driven by the internal dynamics of the dead material within the tumour. Investigations of the parameter sub-space describing the properties of the dead material reveal that the way in which non-viable tumour cells are modelled may significantly influence the qualitative tumour growth dynamics.

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Three-Phase Planar Eutectic Growth Models for a Ternary Eutectic System

Materials Transactions JIM ◽

10.2320/matertrans1989.40.665 ◽

1999 ◽

Vol 40 (7) ◽

pp. 665-674 ◽

Cited By ~ 59

Author(s):

Toshiaki Himemiya ◽

Takateru Umeda

Keyword(s):

Growth Models ◽

Ternary Eutectic ◽

Eutectic Growth ◽

Eutectic System ◽

Three Phase

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Exotic three-phase microstructures in the ternary Ag-Cu-Sb eutectic system

Acta Materialia ◽

10.1016/j.actamat.2021.117400 ◽

2021 ◽

pp. 117400

Author(s):

Shanmukha Kiran Aramanda ◽

Kamanio Chattopadhyay ◽

Abhik Choudhury

Keyword(s):

Eutectic System ◽

Three Phase

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Kinetic behavior of heterotrophic and autotrophic biofilms in wastewater treatment processes

Water Science & Technology ◽

10.2166/wst.1994.0783 ◽

1994 ◽

Vol 29 (10-11) ◽

pp. 385-391 ◽

Cited By ~ 20

Author(s):

M. Moreau ◽

Y. Liu ◽

B. Capdeville ◽

J. M. Audic ◽

L. Calvez

Keyword(s):

Removal Rate ◽

Growth Dynamics ◽

Fluidised Bed ◽

Active Biomass ◽

Substrate Removal ◽

Treatment Processes ◽

Three Phase ◽

Biological Substrate ◽

Autotrophic Biofilms ◽

Fluidised Bed Reactor

Conventional laboratory scale annular reactors were employed to investigate the growth dynamics of both heterotrophic and autotrophic biofilms. Based on the experimental observations and physiological aspects, which consist of defining two types of biomass: active biomass (Ma) responsible for substrate removal, and non-active biomass (Md), which plays no role in the biological substrate removal process but is responsible for the observed additional accumulation of biofilms. The experimental results showed that the biological constants were strongly dependent on the influent substrate concentration (So). It was found that the same was true for the volumic substrate removal rate (kov), which shows a surface reaction independent of the film thickness, and that substrate removal in both heterotrophic and autotrophic biofilm reactors remains reactive. The results demonstrated that thinner biofilms ranging from 20 to 30μm have a higher specific removal rate. It is preferable to use thin biofilms for attached culture industrial processes such as three-phase fluidized-bed and turbulent reactors. The results showed that it is possible to eliminate very high carbon loadings up to 10 to 15 kgTOD/m3/d in a three-phase fluidised-bed reactor, and promising results were obtained for simultaneous removal of carbon and nitrogen in the turbulent bed.

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Cristal-growth dynamics of n-doped gaAs

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100132352 ◽

1992 ◽

Vol 50 (2) ◽

pp. 1544-1545

Author(s):

Pham V. Huong ◽

Stéphanie Bouchet ◽

Jean-Claude Launay

Keyword(s):

Crystal Growth ◽

Spatial Resolution ◽

Epitaxial Layer ◽

Outer Surface ◽

Gaas Substrate ◽

Structural Modification ◽

Growth Dynamics ◽

Argon Laser ◽

High Anisotropy ◽

Crystal Gaas

Microstructure of epitaxial layers of doped GaAs and its crystal growth dynamics on single crystal GaAs substrate were studied by Raman microspectroscopy with a Dilor OMARS instrument equipped with a 1024 photodiode multichannel detector and a ion-argon laser Spectra-Physics emitting at 514.5 nm.The spatial resolution of this technique, less than 1 μm2, allows the recording of Raman spectra at several spots in function of thickness, from the substrate to the outer deposit, including areas around the interface (Fig.l).The high anisotropy of the LO and TO Raman bands is indicative of the orientation of the epitaxial layer as well as of the structural modification in the deposit and in the substrate at the interface.With Sn doped, the epitaxial layer also presents plasmon in Raman scattering. This fact is already very well known, but we additionally observed that its frequency increases with the thickness of the deposit. For a sample with electron density 1020 cm-3, the plasmon L+ appears at 930 and 790 cm-1 near the outer surface.

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In situ TEM observations of melting in nanosized eutectic Pb-Cd inclusions embedded in Al

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100167391 ◽

1996 ◽

Vol 54 ◽

pp. 986-987

Author(s):

S. Hagège ◽

U. Dahmen ◽

E. Johnson ◽

A. Johansen ◽

V.S. Tuboltsev

Keyword(s):

Electron Microscope ◽

Melt Spinning ◽

Ternary Alloys ◽

Solid Matrix ◽

Eutectic System ◽

In Situ Tem ◽

In Situ Observation ◽

Orientation Relationships ◽

Transmission Electron

Small particles of a low-melting phase embedded in a solid matrix with a higher melting point offer the possibility of studying the mechanisms of melting and solidification directly by in-situ observation in a transmission electron microscope. Previous studies of Pb, Cd and other low-melting inclusions embedded in an Al matrix have shown well-defined orientation relationships, strongly faceted shapes, and an unusual size-dependent superheating before melting.[e.g. 1,2].In the present study we have examined the shapes and thermal behavior of eutectic Pb-Cd inclusions in Al. Pb and Cd form a simple eutectic system with each other, but both elements are insoluble in solid Al. Ternary alloys of Al (Pb,Cd) were prepared from high purity elements by melt spinning or by sequential ion implantation of the two alloying additions to achieve a total alloying addition of up to lat%. TEM observations were made using a heating stage in a 200kV electron microscope equipped with a video system for recording dynamic behavior.

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