Distribution and Transport of Charge Carriers in Heterogeneous Electrolyte Systems

1988 ◽  
Vol 135 ◽  
Author(s):  
Joachim Maier
Keyword(s):  
Charge Carriers ◽  
Polycrystalline Materials ◽  
Composite Electrolytes ◽  
Solid Materials ◽  
Two Phase ◽  
Different Types ◽  
Heterogeneous Doping ◽  
Additional Conductivity ◽  
Catalytic Effects ◽  
Interface Effects

AbstractThe thermodynamic point defect concentrations for both ionic (majority) as well as electronic (minority) charge carriers are considered for different types of heterogeneities appearing in ionically conductive solid materials systems. Particularly, the electrical conductivity is discussed for different types of composite electrolytes. Quantitative space charge arguments are shown to be able to explain a variety of different phenomena such as: unusual enhancement of ionic conductivity in two phase samples and in polycrystalline materials, additional conductivity effects in microsized systems; change from cationic to anionic conduction due to heterogeneous doping; simultaneous enhancement of n- and p-conductivity in different electrolyte/ alumina samples, catalytic effects in composite electrolytes as well as chemical interface effects.

COMPARISON OF THE EFFECTS OF DIFFERENT TYPES OF TUBE INSERTS ON TWO-PHASE FLOW INSTABILITIES

2013 ◽  
Vol 20 (2) ◽  
pp. 179-194 ◽  
Author(s):  
Gokhan Omeroglu ◽  
Omer Gomakh ◽  
Sendogan Karagoz ◽  
Suleyman Karsli
Keyword(s):  
Two Phase Flow ◽  
Flow Instabilities ◽  
Phase Flow ◽  
Two Phase ◽  
Different Types

scholarly journals Effects of Polydispersity on the Phase Behavior of Additive Hard Spheres in Solution

Molecules ◽  
2021 ◽  
Vol 26 (6) ◽  
pp. 1543
Author(s):  
Luka Sturtewagen ◽  
Erik van der Linden
Keyword(s):  
Phase Behavior ◽  
Critical Point ◽  
Volume Fraction ◽  
Hard Spheres ◽  
Second Virial Coefficient ◽  
Two Phase ◽  
Different Types ◽  
Asymmetric Partitioning ◽  
Average Size ◽  
Liquid Liquid Phase Separation

The ability to separate enzymes, nucleic acids, cells, and viruses is an important asset in life sciences. This can be realised by using their spontaneous asymmetric partitioning over two macromolecular aqueous phases in equilibrium with one another. Such phases can already form while mixing two different types of macromolecules in water. We investigate the effect of polydispersity of the macromolecules on the two-phase formation. We study theoretically the phase behavior of a model polydisperse system: an asymmetric binary mixture of hard spheres, of which the smaller component is monodisperse and the larger component is polydisperse. The interactions are modelled in terms of the second virial coefficient and are assumed to be additive hard sphere interactions. The polydisperse component is subdivided into sub-components and has an average size ten times the size of the monodisperse component. We calculate the theoretical liquid–liquid phase separation boundary (the binodal), the critical point, and the spinodal. We vary the distribution of the polydisperse component in terms of skewness, modality, polydispersity, and number of sub-components. We compare the phase behavior of the polydisperse mixtures with their concomittant monodisperse mixtures. We find that the largest species in the larger (polydisperse) component causes the largest shift in the position of the phase boundary, critical point, and spinodal compared to the binary monodisperse binary mixtures. The polydisperse component also shows fractionation. The smaller species of the polydisperse component favor the phase enriched in the smaller component. This phase also has a higher-volume fraction compared to the monodisperse mixture.

Different types of aqueous two-phase systems for biomolecule and bioparticle extraction and purification

2013 ◽  
Vol 29 (6) ◽  
pp. 1343-1353 ◽  
Author(s):  
João Vitor Dutra Molino ◽  
Daniela de Araújo Viana Marques ◽  
Adalberto Pessoa Júnior ◽  
Priscila Gava Mazzola ◽  
Maria Silvia Viccari Gatti
Keyword(s):  
Two Phase ◽  
Extraction And Purification ◽  
Different Types ◽  
Aqueous Two Phase Systems ◽  
Phase Systems

scholarly journals Analysis of Microstructure Images Referred to Percolation Theory

2015 ◽  
Vol 15 (1) ◽  
pp. 109-112 ◽  
Author(s):  
W. Trzaskowski ◽  
W. Sobaszek ◽  
D. Myszka ◽  
S. Świłło
Keyword(s):  
Percolation Theory ◽  
Spatial Arrangement ◽  
Polycrystalline Materials ◽  
Practical Implementation ◽  
Material Structure ◽  
Two Phase ◽  
Modern Computer ◽  
Planar Images ◽  
Metallographic Image Analysis

Abstract The paper discusses possible applications of the percolation theory in analysis of the microstructure images of polycrystalline materials. Until now, practical use of this theory in metallographic studies has been an almost unprecedented practice. Observation of structures so intricate with the help of this tool is far from the current field of its application. Due to the complexity of the problem itself, modern computer programmes related with the image processing and analysis have been used. To enable practical implementation of the task previously established, an original software has been created. Based on cluster analysis, it is used for the determination of percolation phenomena in the examined materials. For comparative testing, two two-phase materials composed of phases of the same type (ADI matrix and duplex stainless steel) were chosen. Both materials have an austenitic - ferritic structure. The result of metallographic image analysis using a proprietary PERKOLACJA.EXE computer programme was the determination of the content of individual phases within the examined area and of the number of clusters formed by these phases. The outcome of the study is statistical information, which explains and helps in better understanding of the planar images and real spatial arrangement of the examined material structure. The results obtained are expected to assist future determination of the effect that the internal structure of two-phase materials may have on a relationship between the spatial structure and mechanical properties.

The Influence of External Electric Field on Heat Transfer at Boiling on Non-Uniform Surfaces

2010 ◽  
Author(s):  
Alexey A. Eronin ◽  
Stanislav P. Malyshenko ◽  
Anton I. Zhuravlev
Keyword(s):  
Heat Transfer ◽  
Electric Field ◽  
Electric Fields ◽  
Heated Surface ◽  
Transfer Enhancement ◽  
Two Phase ◽  
Major Mechanism ◽  
External Electric Fields ◽  
Different Types ◽  
Field Traps

Characteristics of heat transfer and hydrodynamics of boiling of liquid nitrogen on the surfaces with different types of non-uniformities at the presence of external electric fields are experimentally investigated. It is shown that the formation of field traps is a major mechanism of heat transfer enhancement. And this effect result in noticeable change of two-phase hydrodynamics in vicinity of heated surface.

Two-Phase Flow Distribution in a Compact Heat Exchanger Header

2003 ◽  
Author(s):  
Jong-Soo Kim ◽  
Yong-Bin Im ◽  
Jae-Hong Kim ◽  
Ki-Taek Lee
Keyword(s):  
Heat Exchanger ◽  
Two Phase Flow ◽  
Phase Distribution ◽  
Flow Distribution ◽  
Compact Heat Exchanger ◽  
Phase Flow ◽  
Two Phase ◽  
Insertion Depth ◽  
Different Types ◽  
Uniform Liquid

In this paper an experimental study was investigated for two-phase distribution in compact heat exchanger header. A test section was consisted of the horizontal header (circular tube: φ 5 mm × 80 mm) and 10 upward circular channels (φ 1.5 mm × 850 mm) using acrylic tube. Three different types of tube insertion depth were tested for the mass flux and inlet quality ranges of 50–200 kg/m2s and 0.1–0.3, respectively. Air and water were used as the test fluids. The distribution of vapor and liquid is obtained by measurement of the total mass flow rate and the calculation of the quality. Two-phase flow pattern was observed, and pressure drop of each channel was measured. By adjusting the insertion depth of each channel a uniform liquid flow distribution through the each channel was able to solve the mal-distribution problem.

scholarly journals Developing Adaptive Serious Games for Children With Specific Learning Difficulties: A Two-phase Usability and Technology Acceptance Study (Preprint)

2021 ◽  
Author(s):  
Oguzcan Yildirim ◽  
Elif Surer
Keyword(s):  
Technology Acceptance ◽  
Serious Games ◽  
Learning Difficulties ◽  
Two Phase ◽  
Training Material ◽  
System Usability Scale ◽  
System Usability ◽  
Different Types ◽  
First Interview ◽  
Specific Learning

BACKGROUND Specific learning difficulties (SpLD) include several disorders such as dyslexia, dyscalculia, and dysgraphia, and the children with these SpLD receive special education. However, the studies and the educational material so far focus mainly on one specific disorder. OBJECTIVE This study’s primary goal is to develop comprehensive training material for different types of SpLD, with five serious games addressing different aspects of the SpLD. The second focus is measuring the impact of adaptive difficulty level adjustment in the children’s and their educators’ usability and technology acceptance perception. Receiving feedback from the children and their educators, and refining the games according to their suggestions have also been essential in this two-phase study. METHODS A total of 10 SpLD educators and 23 children with different types of SpLD tested the prototypes of the five serious games (ie, Word game, Memory game, Category game, Space game, and Math game), gave detailed feedback, answered the System Usability Scale and Technology Acceptance Model (TAM) questionnaires, and applied think-aloud protocols during game play. RESULTS The games’ standard and adaptive versions were analyzed in terms of average playtime and the number of false answers. Detailed analyses of the interviews, with word clouds and player performances, were also provided. The TAM questionnaires’ average and mean values and box plots of each data acquisition session for the children and the educators were also reported via System Usability Scale and TAM questionnaires. The TAM results of the educators had an average of 8.41 (SD 0.87) out of 10 in the first interview and an average of 8.71 (SD 0.64) out of 10 in the second interview. The children had an average of 9.07 (SD 0.56) out of 10 in the first interview. CONCLUSIONS Both the educators and the children with SpLD enjoyed playing the games, gave positive feedback, and suggested new ways for improvement. The results showed that these games provide thorough training material for different types of SpLD with personalized and tailored difficulty systems. The final version of the proposed games will become a part of the special education centers’ supplementary curriculum and training materials, making new enhancements and improvements possible in the future.

scholarly journals Preparation and Characterization of Sulfonated Carbon Cryogel Doped Zinc as a Catalyst for Glucose Ethanolysis to Ethyl Levulinate

2021 ◽  
Vol 21 (1) ◽  
pp. 1
Author(s):  
Muzakkir Mohammad Zainol ◽  
Mohamad Nor Fitri Roslan ◽  
Mohd Asmadi ◽  
Nor Aishah Saidina Amin
Keyword(s):  
Chemical Properties ◽  
Catalyst Loading ◽  
Solid Catalyst ◽  
Ethyl Levulinate ◽  
Different Types ◽  
Carbon Cryogel ◽  
Physical And Chemical ◽  
Catalytic Effects ◽  
And Chemical Properties

In this study, sulfonated carbon cryogel (CC) doped with zinc was prepared and used as a solid catalyst. Carbon cryogel was prepared by mixing urea and furfural, freeze-drying, and calcination. The CC was then sulfonated and impregnated with zinc (II) nitrate for ethyl levulinate production from ethanolysis of glucose. Experiment results showed that different types of catalyst prepared from CC precursor had different catalytic effects on the ethanolysis of glucose. Sulfonated carbon cryogel doped with zinc (SCC-Zn) which prepared at a calcination temperature of 300 °C showed better performance as a catalyst for the ethanolysis reaction of glucose. In addition, the 10 wt.% of Zn was recommended as optimum loading for the impregnation on the catalyst. The ethyl levulinate yield of 19.6 mol% was obtained at 180 °C for 6 h with 0.15 g catalyst loading and 0.4 g of glucose feed. The selected SCC-Zn catalyst was further characterized by using FTIR, TGA XRD, and SEM-EDX to evaluate its physical and chemical properties as a catalyst.

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