A Quantitative Model of Surface Segregation in III-V Ternary Compounds

2000 ◽  
Vol 618 ◽  
Author(s):  
Sergey Yu. Karpov ◽  
Yuri N. Makarov
Keyword(s):  
Surface Segregation ◽  
Quantitative Model ◽  
Model Verification ◽  
Key Factors ◽  
Underlying Assumption ◽  
Factors Affecting ◽  
Surface Population ◽  
Theoretical Predictions ◽  
Good Agreement ◽  
Crystal Bulk

ABSTRACTA quantitative model of surface segregation free from adjustable parameters is suggested for the growth of ternary III-V compounds. In contrast to previous approaches, the model considers the dynamics of surface population by the three elements producing the ternary alloy. The underlying assumption is that the atoms in the adsorption layer are in equilibrium with the crystal bulk. Elastic strain arising in the epitaxial layer due to the lattice constant mismatch with the substrate is found to be one of the key factors affecting segregation. Along with growth temperature, it controls the segregation efficiency and the composition profile evolution in a growing heterostructure. The effect of the V/III ratio, growth rate and other parameters is accounted for. Here, we apply the model to analyze the InGaAs growth by molecular beam epitaxy owing to the vast experimental data available for the model verification. The theoretical predictions show a good agreement with the experimental observations

Dehydration of Fractal Particles of Iron (III) and Aluminum Hydroxides

1995 ◽  
Vol 407 ◽  
Author(s):  
A. A. Vertegel ◽  
S. V. Kalinin ◽  
N. N. Oleynikov ◽  
Yu. D. Tretyakov
Keyword(s):  
Experimental Data ◽  
Fractal Dimension ◽  
Metal Atom ◽  
Quantitative Model ◽  
Kinetic Behavior ◽  
Dehydration Rate ◽  
Aluminum Hydroxides ◽  
Theoretical Predictions ◽  
Fractal Particles ◽  
Good Agreement

ABSTRACTThe kinetic behavior of Fe(OH)3 and AI(OH)3 powders during thermal dehydration is investigated. It has been shown that the dehydration rate is governed by the value of fractal dimension of the sample without any respect to the nature of metal atom in hydroxide. The quantitative model for dehydration of fractal particles with particular value of fractal dimension is suggested. Theoretical predictions are in a good agreement with experimental data.

scholarly journals Tension modeling of package binding belts in cargo spacecraft

2018 ◽  
Vol 198 ◽  
pp. 05006
Author(s):  
Weifeng Yuan ◽  
Hailin Dai ◽  
Ruizhao Du
Keyword(s):  
Coupling Model ◽  
Quantitative Model ◽  
Model Verification ◽  
Loading Test ◽  
Dimension Analysis ◽  
Test Platform ◽  
Tension Sensor ◽  
Packing Process ◽  
Force Data ◽  
Good Agreement

At the site of cargo package binding in cargo spacecraft, the binding belt tension is loaded with a ratchet device. It is determined by experience of operators, therefore it’s difficult to quantify the force and the reliability of the binding belt is low. Based on the dimension analysis method, a semi-quantitative model was established between the binding belt tension and the ratchet force of the fastening device. The motion of the binding process was carefully observed and analyzed based on Analysis of Therbligs. On this basis, the standard packing process is developed, which improves the repeatability of loading and packing pre loading. A loading test platform for cargo loading is built with small tension sensor and tension tester, and a large number of tension data and ratchet force data are obtained. Based on the least-squares linear data fitting, four coupling models for the four binding belts were established. The coupling model verification experiments show that the calculated values are in good agreement with the measured values, and the errors are mostly lower than 5%. The model can be applied to the quantification of the binding belt tension.

The influence of microstructure on the electrochromic properties of LixWO3 films: Part II. Limiting mechanisms in coloring and bleaching processes

1993 ◽  
Vol 8 (10) ◽  
pp. 2657-2667 ◽  
Author(s):  
Ji-Guang Zhang ◽  
David K. Benson ◽  
Edwin C. Tracy ◽  
Satyen K. Deb
Keyword(s):  
Structural Changes ◽  
Lithium Concentration ◽  
Quantitative Model ◽  
Experimental Conditions ◽  
Bleaching Process ◽  
Factors Affecting ◽  
Diffusion Impedance ◽  
Electrolyte Resistance ◽  
Circuit Resistance ◽  
Good Agreement

Various factors affecting the coloring and bleaching processes of LixWO3 films have been studied. The rate of the coloring process is limited by the decreasing electromotive force in the LixWO3 film and by the components of the series circuit resistance, including the electrolyte resistance and the diffusion impedance within the film. The bleaching process in a thick film is limited by either the space charge or by the diffusion impedance, depending on the experimental conditions. A more complete and quantitative model of the coloring/bleaching process has been developed and shows good agreement with experimental results. Our analysis also indicates that the lithium concentration value of x near the LixWO3/electrolyte interface can greatly exceed its reversible limit during the coloring process, even though the average x value within the film remains much lower than the reversible limit. This phenomenon may introduce some irreversible structural changes in the film, which in turn may constitute one of the film's degradation mechanisms.

EVALUATION OF FINANCIAL SECURITY OF THE REPUBLIC OF CRIMEA

2020 ◽  
pp. 56-67
Author(s):  
Elena Evgenevna Mashyanova ◽  
Elena Aleksandrovna Smirnova
Keyword(s):  
Financial Markets ◽  
Negative Impact ◽  
Gradual Increase ◽  
Financial System ◽  
Financial Security ◽  
Key Factors ◽  
Factors Affecting ◽  
External Threats ◽  
The Republic ◽  
Global Financial System

In modern conditions of development, financial security is an integral part of the overall security of the region and is formed on the basis of the functioning of the financial system. The complication of relationships between key segments of international financial markets, as well as the limited ability to accurately predict future trends in the development of the global financial system, lead to a gradual increase in the risks that accompany the activities of economic entities, and an increase in the number and scale of internal and external threats that have a negative impact on the financial security of the state. This formulation of the issue requires generalization of approaches to determining the financial security of the region in order to further formalize this issue and determine the key factors affecting it. The article considers the types of financial security, as well as certain areas of ensuring the financial security of the region and their priority. In work the assessment of the level of socio-economic development of the region with a view to ensuring financial security on the basis of which offers the main activities and priority areas of implementation of the investment policy that will ensure financial security of the Republic of Crimea.

scholarly journals A Generalized Approach for Evaluating the Mechanical Properties of Polymer Nanocomposites Reinforced with Spherical Fillers

Nanomaterials ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 830
Author(s):  
Julio Cesar Martinez-Garcia ◽  
Alexandre Serraïma-Ferrer ◽  
Aitor Lopeandía-Fernández ◽  
Marco Lattuada ◽  
Janak Sapkota ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Polymeric Nanocomposites ◽  
Mechanical Reinforcement ◽  
Future Studies ◽  
Three Phase ◽  
Theoretical Predictions ◽  
Filler Network ◽  
New Research ◽  
Good Agreement ◽  
Research Avenue

In this work, the effective mechanical reinforcement of polymeric nanocomposites containing spherical particle fillers is predicted based on a generalized analytical three-phase-series-parallel model, considering the concepts of percolation and the interfacial glassy region. While the concept of percolation is solely taken as a contribution of the filler-network, we herein show that the glassy interphase between filler and matrix, which is often in the nanometers range, is also to be considered while interpreting enhanced mechanical properties of particulate filled polymeric nanocomposites. To demonstrate the relevance of the proposed generalized equation, we have fitted several experimental results which show a good agreement with theoretical predictions. Thus, the approach presented here can be valuable to elucidate new possible conceptual routes for the creation of new materials with fundamental technological applications and can open a new research avenue for future studies.

scholarly journals Comparison of the sensitivity of Western blotting between PVDF and NC membranes

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Yufang Xiang ◽  
Yuanyuan Zheng ◽  
Shaobo Liu ◽  
Gang Liu ◽  
Zhi Li ◽  
...  
Keyword(s):  
Western Blotting ◽  
Polyvinylidene Fluoride ◽  
Staining Intensity ◽  
Detection Sensitivity ◽  
Key Factors ◽  
Post Translational Modifications ◽  
Factors Affecting ◽  
Molecular Weights ◽  
Direct Blue ◽  
The Relationship

AbstractWestern blotting (WB) is one of the most widely used techniques to identify proteins as well as post translational modifications of proteins. The selection of electroblotted membrane is one of the key factors affecting the detection sensitivity of the protein which is transferred from gel to membrane in WB. The most common used membranes are polyvinylidene fluoride (PVDF) and nitrocellulose (NC) membranes. Which membrane of these two is more suitable for WB has not been reported so far. Here, by incubating proteins which were transferred to PVDF or NC membranes with a series of antibodies and different types of lectins, we investigated the relationship between the binding ability of these two membranes to proteins or glycoproteins and the molecular weight of the target protein. The antibody re-probed ability of the two membranes was also explored. Moreover, we verified the above results by directly incubating proteins having different molecular weights onto PVDF or NC membranes. Bound proteins were stained with direct blue-71, and the staining intensity was quantitated by scanning and densitometry.

scholarly journals The Effects of Mobility as a Service and Autonomous Vehicles on People’s Willingness to Own a Car in the Future

2021 ◽  
Vol 13 (4) ◽  
pp. 1962
Author(s):  
Timo Liljamo ◽  
Heikki Liimatainen ◽  
Markus Pöllänen ◽  
Riku Viri
Keyword(s):  
Public Transport ◽  
Autonomous Vehicles ◽  
Travel Behaviour ◽  
Car Ownership ◽  
Key Factors ◽  
Sustainable Mobility ◽  
Factors Affecting ◽  
Mobility Service ◽  
The Future ◽  
Mobility Behaviour

Car ownership is one of the key factors affecting travel behaviour and thus also essential in terms of sustainable mobility. This study examines car ownership and how people’s willingness to own a car may change in the future, when considering the effects of public transport, Mobility as a Service (MaaS) and automated vehicles (AVs). Results of two citizen surveys conducted with representative samples (NAV-survey = 2036; NMaaS-survey = 1176) of Finns aged 18–64 are presented. The results show that 39% of respondents would not want or need to own a car if public transport connections were good enough, 58% if the described mobility service was available and 65% if all vehicles in traffic were automated. Hence, car ownership can decrease as a result of the implementation of AVs and MaaS, and higher public transport quality of service. Current mobility behaviour has a strong correlation to car ownership, as respondents who use public transport frequently feel less of a will or need to own a car than others. Generally, women and younger people feel less of a will or need to own a car, but factors such as educational level and residential location seem to have a relatively low effect.

scholarly journals Optimize Design of Run-Flat Tires by Simulation and Experimental Research

Materials ◽  
2021 ◽  
Vol 14 (3) ◽  
pp. 474
Author(s):  
Huaqiao Liu ◽  
Yiren Pan ◽  
Huiguang Bian ◽  
Chuansheng Wang
Keyword(s):  
Stress Distribution ◽  
Energy Loss ◽  
Successful Implementation ◽  
Performance Tests ◽  
Key Factors ◽  
Heat Accumulation ◽  
Factors Affecting ◽  
Structural Rigidity ◽  
Key Factor ◽  
Durability Testing

In this study, the two key factors affecting the thermal performance of the insert rubber and stress distribution on the tire sidewall were analyzed extensively through various performance tests and simulations to promote the development of run-flat tires. Four compounds and two structures of insert rubber were designed to investigate the effects of heat accumulation and stress distribution on durability testing at zero pressure. It was concluded that the rigidity and tensile strength of the compound were negatively correlated with temperature. The deformation was a key factor that affects energy loss, which could not be judged solely by the loss factor. The stress distribution, however, should be considered in order to avoid early damage of the tire caused by stress concentration. On the whole, the careful balance of mechanical strength, energy loss, and structural rigidity was the key to the optimal development of run-flat tires. More importantly, the successful implementation of the simulations in the study provided important and useful guidance for run-flat tire development.

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