scholarly journals Comparison of Lateral Non-uniformity Phenomena between HfO2 and SiO2 from Magnified C-V Curves in Inversion Region

2019 ◽  
Vol 25 (6) ◽  
pp. 327-338 ◽  
Author(s):  
Jen-Yuan Cheng ◽  
Chiao-Ti Huang ◽  
Hui-Ting Lu ◽  
Jenn-Gwo Hwu
Keyword(s):  
Inversion Region

Effect of Shear and Water Cut on Phase Inversion and Droplet Size Distribution in Oil–Water Flow

2018 ◽  
Vol 141 (3) ◽  
Author(s):  
Mo Zhang ◽  
Ramin Dabirian ◽  
Ram S. Mohan ◽  
Ovadia Shoham
Keyword(s):  
Size Distribution ◽  
Droplet Size ◽  
Phase Inversion ◽  
Droplet Size Distribution ◽  
Continuous Phase ◽  
Dispersed Phase ◽  
Water Emulsion ◽  
Inversion Region ◽  
Oil Water ◽  
Water Cut

Oil–water dispersed flow occurs commonly in the petroleum industry during the production and transportation of crudes. Phase inversion occurs when the dispersed phase grows into the continuous phase and the continuous phase becomes the dispersed phase caused by changes in the composition, interfacial properties, and other factors. Production equipment, such as pumps and chokes, generates shear in oil–water mixture flow, which has a strong effect on phase inversion phenomena. The objective of this paper is to investigate the effects of shear intensity and water cut (WC) on the phase inversion region and also the droplet size distribution. A state-of-the-art closed-loop two phase (oil–water) flow facility including a multipass gear pump and a differential dielectric sensor (DDS) is used to identify the phase inversion region. Also, the facility utilizes an in-line droplet size analyzer (a high speed camera), to record real-time videos of oil–water emulsion to determine the droplet size distribution. The experimental data for phase inversion confirm that as shear intensity increases, the phase inversion occurs at relatively higher dispersed phase fractions. Also the data show that oil-in-water emulsion requires larger dispersed phase volumetric fraction for phase inversion as compared with that of water-in-oil emulsion under the same shear intensity conditions. Experiments for droplet size distribution confirm that larger droplets are obtained for the water continuous phase, and increasing the dispersed phase volume fraction leads to the creation of larger droplets.

Partitioning of the components into two-demixed-macrophases from a solution blend emulating high impact polystyrene close to the phase inversion region

Polymer ◽  
2020 ◽  
Vol 198 ◽  
pp. 122523
Author(s):  
Eliezer Velásquez ◽  
Ilibeth Morales ◽  
María Montero ◽  
Haydée Oliva ◽  
Alejandro J. Müller ◽  
...  
Keyword(s):  
Phase Inversion ◽  
High Impact ◽  
Inversion Region ◽  
High Impact Polystyrene

scholarly journals Highly mobile DNA segment of IncI alpha plasmid R64: a clustered inversion region.

1986 ◽  
Vol 165 (1) ◽  
pp. 94-100 ◽  
Author(s):  
T Komano ◽  
A Kubo ◽  
T Kayanuma ◽  
T Furuichi ◽  
T Nisioka
Keyword(s):  
Mobile Dna ◽  
Inversion Region ◽  
Plasmid R64

The Absence of a Marcus Inversion Region for Electron Transfer at the Metal-Redox Electrolyte Interface

1994 ◽  
Vol 47 (12) ◽  
pp. 2171 ◽  
Author(s):  
D Matthews
Keyword(s):  
Electron Transfer ◽  
Potential Energy ◽  
Electron Distribution ◽  
Distribution Functions ◽  
Rate Distribution ◽  
Inversion Region ◽  
Redox Electrolyte ◽  
Electrolyte Interface ◽  
Metal Redox ◽  
Nuclear Configuration

The theory of electron transfer at the metal- redox electrolyte interface is described by starting with the work of Gurney and incorporating that of Gerischer and Marcus. This GGM model brings together diverse approaches to the description of electron transfer at electrodes. The electron transfer is described in terms of nuclear configuration potential energy diagrams, electronic configuration potential energy diagrams, electron distribution functions and rate distribution functions. The distinction between microscopic energies and macroscopic (thermodynamic) energies is made and the concept of the Fermi level of the redox electrolyte is clarified. The model of identical parabolas is used for the nuclear configuration diagrams and this is shown to lead to Gaussian electron distribution functions for the redox electrolyte. The rate distribution is obtained from the overlap between occupied and unoccupied states of the metal and redox electrolyte. Integration of the rate distribution gives the rate which is calculated as a function of the electrode potential for various values of the reorganization energy λ. It is shown that the variation of symmetry factor β is small for high λ and that the Tafel plots do not show significant decrease in rate at high overpotentials in the anomalous or inversion region. The Tafel plots for charge transfer (mass transfer is assumed to be fast at all potentials) tend to a limiting value with only a small decrease at high overpotential. This contrasts with the prediction based on nuclear configuration potential energy curves and is attributed to the fact that the overlap is between a Gaussian and a Fermi function rather than between two Gaussians, the latter being the case for homogeneous reactions.

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