Search results for: Cold atmospheric plasma
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 659

Search results for: Cold atmospheric plasma

389 Two-Dimensional Solitary Wave Solution to the Quadratic Nonlinear Schrdinger Equation

Authors: Sarun Phibanchon

Abstract:

The solitary wave solution of the quadratic nonlinear Schrdinger equation is determined by the iterative method called Petviashvili method. This solution is also used for the initial condition for the time evolution to study the stability analysis. The spectral method is applied for the time evolution.

Keywords: soliton, iterative method, spectral method, plasma

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388 Oxidation of Carbon Monoxide in a Monolithic Reactor

Authors: S. Chauhan, T.P.K. Grewal, S.K. Aggarwal, V.K. Srivastava

Abstract:

Solution for the complete removal of carbon monoxide from the exhaust gases still poses a challenge to the researchers and this problem is still under development. Modeling for reduction of carbon monoxide is carried out using heterogeneous reaction using low cost non-noble metal based catalysts for the purpose of controlling emissions released to the atmosphere. A simple one-dimensional model was developed for the monolith using hopcalite catalyst. The converter is assumed to be an adiabatic monolith operating under warm-up conditions. The effect of inlet gas temperatures and catalyst loading on carbon monoxide reduction during cold start period in the converter is analysed.

Keywords: carbon monoxide, catalytic, modeling, monolith

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387 Formation of Round Channel for Microfluidic Applications

Authors: A. Zahra, G. de Cesare, D. Caputo, A. Nascetti

Abstract:

PDMS (Polydimethylsiloxane) polymer is a suitable material for biological and MEMS (Microelectromechanical systems) designers, because of its biocompatibility, transparency and high resistance under plasma treatment. PDMS round channel is always been of great interest due to its ability to confine the liquid with membrane type micro valves. In this paper we are presenting a very simple way to form round shapemicrofluidic channel, which is based on reflow of positive photoresist AZ® 40 XT. With this method, it is possible to obtain channel of different height simply by varying the spin coating parameters of photoresist.

Keywords: Lab-on-Chip, PDMS, Reflow, Round microfluidic channel.

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386 Modern Kazakhstan in Global World After Independence

Authors: Dmitri Men, Byong-soon Chun, Soon-ok Myong

Abstract:

The article deals with the problems of political and economic processes in Kazakhstan since independence in the context of globalization. It analyzes the geopolitical situation and selfpositioning processes in the world after the end of the "cold war". It examines the problems of internal economization of the Republic for 20 years of independence. The authors argue that the reforms proceeded in the economic sphere have brought ambiguous and tangible results. Despite the difficult economic and political conditions facing a world economical crisis the country has undergone fundamental and radical transformations in the whole socio-economic system

Keywords: Globalization, Kazakhstan, integration, economic processes, financial crisis, multi-vector.

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385 Culturally Enhanced Collaborative Filtering

Authors: Mahboobe Zardosht, Nasser Ghasem-Aghaee

Abstract:

We propose an enhanced collaborative filtering method using Hofstede-s cultural dimensions, calculated for 111 countries. We employ 4 of these dimensions, which are correlated to the costumers- buying behavior, in order to detect users- preferences for items. In addition, several advantages of this method demonstrated for data sparseness and cold-start users, which are important challenges in collaborative filtering. We present experiments using a real dataset, Book Crossing Dataset. Experimental results shows that the proposed algorithm provide significant advantages in terms of improving recommendation quality.

Keywords: Collaborative filtering, Cross-cultural, E-commerce, Recommender systems

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384 The Impact of Cutting Tool Materials on Cutting Force

Authors: M.A. Kamely, M.Y. Noordin

Abstract:

A judicious choice of insert material, tool geometry and cutting conditions can make hard turning produce better surfaces than grinding. In the present study, an attempt has been made to investigate the effect of cutting tool materials on cutting forces (feed force, thrust force and cutting force) in finish hard turning of AISI D2 cold work tool steel. In conclusion of the results obtained with a constant depth of cut and feed rate, it is important to note that cutting force is directly affected by cutting tool material.

Keywords: hard turning, cutting force, cutting tool materials, mixed ceramic, cbn

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383 Kuehne + Nagel's PharmaChain: IoT-Enabled Product Monitoring Using Radio Frequency Identification

Authors: Rebecca Angeles

Abstract:

This case study features the Kuehne + Nagel PharmaChain solution for ‘cold chain’ pharmaceutical and biologic product shipments with IOT-enabled features for shipment temperature and location tracking. Using the case study method and content analysis, this research project investigates the application of the structurational model of technology theory introduced by Orlikowski in order to interpret the firm’s entry and participation in the IOT-impelled marketplace.

Keywords: Internet of things, IoT, radio frequency identification, supply chain management, business intelligence.

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382 Microstructure and Mechanical Characterization of Heat Treated Stir Cast Silica (Sea Sand) Reinforced 7XXX Al Alloy MMCs

Authors: S. S. Sharma, Jagannath K, P. R. Prabhu

Abstract:

Metal matrix composites consists of a metallic matrix combined with dispersed particulate phase as reinforcement. Aluminum alloys have been the primary material of choice for structural components of aircraft since about 1930. Well known performance characteristics, known fabrication costs, design experience, and established manufacturing methods and facilities, are just a few of the reasons for the continued confidence in 7XXX Al alloys that will ensure their use in significant quantities for the time to come. Particulate MMCs are of special interest owing to the low cost of their raw materials (primarily natural river sand here) and their ease of fabrication, making them suitable for applications requiring relatively high volume production. 7XXX Al alloys are precipitation hardenable and therefore amenable for thermomechanical treatment. Al–Zn alloys reinforced with particulate materials are used in aerospace industries in spite of the drawbacks of susceptibility to stress corrosion, poor wettability, poor weldability and poor fatigue resistance. The resistance offered by these particulates for the moving dislocations impart secondary hardening in turn contributes strain hardening. Cold deformation increases lattice defects, which in turn improves the properties of solution treated alloy. In view of this, six different Al–Zn–Mg alloy composites reinforced with silica (3 wt. % and 5 wt. %) are prepared by conventional semisolid synthesizing process. The cast alloys are solution treated and aged. The solution treated alloys are further severely cold rolled to enhance the properties. The hardness and strength values are analyzed and compared with silica free Al – Zn-Mg alloys. Precipitation hardening phenomena is accelerated due to the increased number of potential sites for precipitation. Higher peak hardness and lesser aging time are the characteristics of thermo mechanically treated samples. For obtaining maximum hardness, optimum number and volume of precipitate particles are required. The Al-5Zn-1Mg with 5% SiO2 alloy composite shows better result.

Keywords: Dislocation, hardness, matrix, thermomechanical, precipitation hardening, reinforcement.

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381 Numerical Simulation of High Pressure Hydrogen Emerges to Air

Authors: Mohamed H. Elhsnawi, Mesbah M. Salem, Saleh B. Mohamed

Abstract:

Numerical simulation performed to investigate the behavior of the high pressure hydrogen jetting of air. High pressure hydrogen (30–40 MPa) was injected to air at atmospheric pressure through 2mm orifice. Numerical simulations were performed with Kiva3V code with 2D axisymmetric geometry. Numerical simulations showed that auto ignition of high pressure hydrogen to air are possible due to molecular diffusion. Auto ignition was predicted at hydrogen-air contact surface due to mass and energy exchange between high temperature hydrogen and air heated by shock wave.

Keywords: Spontaneous Ignition, Diffusion Ignition, Hydrogen ignition, Hydrogen Jet.

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380 The Shanghai Cooperation Organization: China's Grand Strategy in Central Asia

Authors: Mara Gubaidullina, Aigerim Yelibayeva

Abstract:

The Shanghai Cooperation Organization is one of the successful outcomes of China's foreign policy since the end of the Cold war. The expansion of multilateral ties all over the world by dint of pursuing institutional strategies as SCO, identify China as a more constructive power. SCO became a new model of cooperation that was formed on remains of collapsed Soviet system, and predetermined China's geopolitical role in the region. As the fast developing effective regional mechanism, SCO today has more of external impact on the international system and forms a new type of interaction for promoting China's grand strategy of 'peaceful rise'.

Keywords: Central Asia, China's grand strategy, Shanghai Cooperation Organization.

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379 Using HABIT to Establish the Chemicals Analysis Methodology for Maanshan Nuclear Power Plant

Authors: J. R. Wang, S. W. Chen, Y. Chiang, W. S. Hsu, J. H. Yang, Y. S. Tseng, C. Shih

Abstract:

In this research, the HABIT analysis methodology was established for Maanshan nuclear power plant (NPP). The Final Safety Analysis Report (FSAR), reports, and other data were used in this study. To evaluate the control room habitability under the CO2 storage burst, the HABIT methodology was used to perform this analysis. The HABIT result was below the R.G. 1.78 failure criteria. This indicates that Maanshan NPP habitability can be maintained. Additionally, the sensitivity study of the parameters (wind speed, atmospheric stability classification, air temperature, and control room intake flow rate) was also performed in this research.

Keywords: PWR, HABIT, habitability, Maanshan.

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378 Study on Radio Link Availability in Millimeter Wave Range

Authors: Boncho G. Bonev, Kliment N. Angelov, Emil S. Altimirski

Abstract:

In this paper, the link quality in SHF and EHF ranges are studied. In order to achieve high data rate higher frequencies must be used – centimeter waves (SHF), millimeter waves (EHF) or optical range. However, there are significant problem when a radio link work in that diapason – rain attenuation and attenuation in earth-s atmosphere. Based on statistical rain rates data for Bulgaria, the link availability can be determined, depending on the working frequency, the path length and the Power Budget of the link. For the calculations of rain attenuation and atmosphere-s attenuation the ITU recommendations are used.

Keywords: rain attenuation, atmospheric gaseous attenuation, link availability, link breaking probability

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377 The Study of Super Hydrophobic Surfaces Using High Speed Shadowgraphy

Authors: D. Jasikova, M. Kotek, V. Kopecky

Abstract:

The aim of this article is the measurement of the basic characteristic of superhydrophobic surfaces using high speed shadowgraphy. Here we describe the novel patented system for the industrial production of superhydrophobic surfaces. These surfaces were investigated with two optically based measurement methods: impinging drop and inclined wall. The results of the visualization and analysis help to state the suitable sample with superhydrophobic properties for mathematic simulation.

Keywords: Antipearl effect, contact angle, hydrophobic, impinging drop, inclined wall, measurement, plasma, shadowgraphy, superhydrophobic surface.

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376 Changes in Fine PM Pollution Levels with Tightening of Regulations on Vehicle Emissions

Authors: Akihiro Iijima, Kimiyo Kumagai

Abstract:

A long-term campaign for monitoring the concentration of atmospheric Particulate Matter (PM) was conducted at multiple sites located in the center and suburbs of the Tokyo Metropolitan Area in Japan. The concentration of fine PM has shown a declining trend over the last two decades. A positive matrix factorization model elucidated that the contribution of combustion sources was drastically reduced. In Japan, the regulations on vehicle exhaust emissions were phased in and gradually tightened over the last two decades, which has triggered a notable reduction in PM emissions from automobiles and has contributed to the mitigation of the problem of fine PM pollution.

Keywords: Air pollution, Diesel-powered vehicle, Positive matrix factorization, Receptor modeling.

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375 Retrofitting Measures for Existing Housing Stock in Kazakhstan

Authors: S. Yessengabulov, A. Uyzbayeva

Abstract:

Residential buildings fund of Kazakhstan was built in the Soviet time about 35-60 years ago without considering energy efficiency measures. Currently, most of these buildings are in a rundown condition and fail to meet the minimum of hygienic, sanitary and comfortable living requirements. The paper aims to examine the reports of recent building energy survey activities in the country and provide a possible solution for retrofitting existing housing stock built before 1989 which could be applicable for building envelope in cold climate. Methodology also includes two-dimensional modeling of possible practical solutions and further recommendations.

Keywords: Energy audit, energy efficient buildings in Kazakhstan, retrofit, two-dimensional conduction heat transfer analysis

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374 Study of the Behavior of an Organic Coating Applied on Algerian Oil Tanker in Seawater

Authors: N. Hammouda, K. Belmokre

Abstract:

Paints are the most widely used methods of protection against atmospheric corrosion of metals. The aim of this work was to determine the protective performance of epoxy coating against sea water before and after damage. Investigations are conducted using stationary and non-stationary electrochemical tools such as electrochemical impedance spectroscopy has allowed us to characterize the protective qualities of these films. The application of the EIS on our damaged in-situ painting shows the existence of several capacitive loops which is an indicator of the failure of our tested paint. Microscopic analysis (micrograph) helped bring essential elements in understanding the degradation of our paint condition and immersion training corrosion products.

Keywords: Epoxy Paints, Electrochemical Impedance Spectroscopy, Corrosion Mechanisms, sea water.

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373 Nonlinear Simulation of Harmonically Coupled Two-Beam Free-Electron Laser

Authors: M. Zahedian, B. Maraghechi, M. H. Rouhani

Abstract:

A nonlinear model of two-beam free-electron laser (FEL) in the absence of slippage is presented. The two beams are assumed to be cold with different energies and the fundamental resonance of the higher energy beam is at the third harmonic of lower energy beam. By using Maxwell-s equations and full Lorentz force equations of motion for the electron beams, coupled differential equations are derived and solved numerically by the fourth order Runge–Kutta method. In this method a considerable growth of third harmonic electromagnetic field in the XUV and X-ray regions is predicted.

Keywords: Free-electron laser, Higher energy beam, Lowerenergy beam, Two-beam

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372 Experimental Study of Adsorption Properties of Acid and Thermal Treated Bentonite from Tehran (Iran)

Authors: H. R. Moghadamzadeh, M. Naimi, H. Rahimzadeh, M. Ardjmand, V. M. Nansa, A. M. Ghanadi

Abstract:

The Iranian bentonite was first characterized by Scanning Electron Microscopy (SEM), Inductively Coupled Plasma mass spectrometry (ICP-MS), X-ray fluorescence (XRF), X-ray Diffraction (XRD) and BET. The bentonite was then treated thermally between 150°C-250°C at 15min, 45min and 90min and also was activated chemically with different concentration of sulphuric acid (3N, 5N and 10N). Although the results of thermal activated-bentonite didn-t show any considerable changes in specific surface area and Cation Exchange Capacity (CEC), but the results of chemical treated bentonite demonstrated that such properties have been improved by acid activation process.

Keywords: Acid activation, Bentonite, CEC, Thermal activation.

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371 Carbon Dioxide Removal from Flue Gas Using Amine-Based Hybrid Solvent Absorption

Authors: Supitcha Rinprasertmeechai, Sumaeth Chavadej, Pramoch Rangsunvigit, Santi Kulprathipanja

Abstract:

This study was to investigate the performance of hybrid solvents blended between primary, secondary, or tertiary amines and piperazine (PZ) for CO2 removal from flue gas in terms of CO2 absorption capacity and regeneration efficiency at 90 oC. Alkanolamines used in this work were monoethanolamine (MEA), diethanolamine (DEA), and triethanolamine (TEA). The CO2 absorption was experimentally examined under atmospheric pressure and room temperature. The results show that MEA blend with PZ provided the maximum CO2 absorption capacity of 0.50 mol CO2/mol amine while TEA provided the minimum CO2 absorption capacity of 0.30 mol CO2/mol amine. TEA was easier to regenerate for both first cycle and second cycle with less loss of absorption capacity. The regeneration efficiency of TEA was 95.09 and 92.89 %, for the first and second generation cycles, respectively.

Keywords: CO2 absorption capacity, regeneration efficiency, CO2 removal, flue gas

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370 Study on the Atomic-Oxygen-Protection Film Preparation of Organic Silicon and Its Properties

Authors: Zheng-Kuohai, Yang-Shengsheng, Li-Zhonghua, Zhao-Lin

Abstract:

Materials used on exterior spacecraft surfaces are subjected to many environmental threats which can cause degradation, atomic oxygen is one of the most threats. We prepared organic silicon atomic-oxygen-protection film using method of polymerization. This paper presented the effects on the film structure and its durability of the preparation processing, and analyzed the polymerization theory, the film structure and composition of the film. At last, we tested the film in our ground based atomic oxygen simulator, and indicated that the film worked well.

Keywords: Atomic oxygen, siloxane, protection, plasma, polymerization.

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369 The Experimental and Numerical Analysis of the Joining Processes for Air Conditioning Systems

Authors: M.St. Węglowski, D. Miara, S. Błacha, J. Dworak, J. Rykała, K. Kwieciński, J. Pikuła, G. Ziobro, A. Szafron, P. Zimierska-Nowak, M. Richert, P. Noga

Abstract:

In the paper the results of welding of car’s air-conditioning elements are presented. These systems based on, mainly, the environmental unfriendly refrigerants. Thus, the producers of cars will have to stop using traditional refrigerant and to change it to carbon dioxide (R744). This refrigerant is environmental friendly. However, it should be noted that the air condition system working with R744 refrigerant operates at high temperature (up to 150 °C) and high pressure (up to 130 bar). These two parameters are much higher than for other refrigerants. Thus new materials, design as well as joining technologies are strongly needed for these systems. AISI 304 and 316L steels as well as aluminium alloys 5xxx are ranked among the prospective materials. As a joining process laser welding, plasma welding, electron beam welding as well as high rotary friction welding can be applied. In the study, the metallographic examination based on light microscopy as well as SEM was applied to estimate the quality of welded joints. The analysis of welding was supported by numerical modelling based on Sysweld software. The results indicated that using laser, plasma and electron beam welding, it is possible to obtain proper quality of welds in stainless steel. Moreover, high rotary friction welding allows to guarantee the metallic continuity in the aluminium welded area. The metallographic examination revealed that the grain growth in the heat affected zone (HAZ) in laser and electron beam welded joints were not observed. It is due to low heat input and short welding time. The grain growth and subgrains can be observed at room temperature when the solidification mode is austenitic. This caused low microstructural changes during solidification. The columnar grain structure was found in the weld metal. Meanwhile, the equiaxed grains were detected in the interface. The numerical modelling of laser welding process allowed to estimate the temperature profile in the welded joint as well as predicts the dimensions of welds. The agreement between FEM analysis and experimental data was achieved.  

Keywords: Car’s air–conditioning, microstructure, numerical modelling, welding.

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368 Effect of N2 Pretreatment on the Properties of Tungsten-Based Catalysts in Metathesis of Ethylene and 2-Butene

Authors: K. Aranyarat, S. Maksasithorn, K. Suriye, S. Kunjara Na Ayudhya, J. Panpranot

Abstract:

The effect of N2 pretreatment on the catalytic activity of tungsten-based catalysts was investigated in the metathesis of ethylene and trans-2-butene at 450oC and atmospheric pressure. The presence of tungsten active species was confirmed by UV-Vis and Raman spectroscopy. Compared to the WO3-based catalysts treated in air, higher amount of WO4 2-tetrahedral species and lower amount of WO3 crystalline species were observed on the N2-treated ones. These contribute to the higher conversion of 2-butene and propylene selectivity during 10 h time-on-stream. Moreover, N2 treatment led to lower amount of coke formation as revealed by TPO of the spent catalysts.

Keywords: Metathesis, Pretreatment, Propylene, Tungsten.

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367 Biocompatibility of NiTi Alloy Implants in vivo

Authors: Gul Tosun, Emine Ünsaldi Latif Özler, Nuri Orhan, Ali Said Durmus, Hatice Eröksüz

Abstract:

In this study, the powders of Ni and Ti with 50.5 at.% Ni for 12 h were blended and cold pressed at the different pressures (50, 75 and100 MPa).The porous product obtained after Ni-Ti compacts were synthesized by SHS (self-propagating hightemperature synthesis) in the different preheating temperatures (200, 250 and 300oC) and heating rates (30, 60 and 90oC/min). The effects of the pressure, preheating temperature and heating rate were investigated on biocompatibility in vivo. The porosity in the synthesized products was in the range of 50.7–59.7 vol. %. The pressure, preheating temperature and heating rate were found to have an important effect on the biocompatibility in-vivo of the synthesized products. Max. fibrotic tissue within the porous implant was found in vivo periods (6 months), in which compacting pressure 100MPa.

Keywords: NiTi, biomaterial, SHS, biocompatibility.

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366 Quebec Elementary Pre-service Teachers’ Conceptual Representations about Heat and Temperature

Authors: Abdeljalil Métioui

Abstract:

This article identifies the conceptual representations of 128 students enrolled in elementary pre-service teachers’ education in the Province of Quebec, Canada (ages 19-24). To construct their conceptual representations relatively to notions of heat and temperature, we use a qualitative research approach. For that, we distributed them a questionnaire including four questions. The result demonstrates that these students tend to view the temperature as a measure of the hotness of an object or person. They also related the sensation of cold (or warm) to the difference in temperature, and for their majority, the physical change of the matter does not require a constant temperature. These representations are inaccurate relatively to the scientific views, and we will see that they are relevant to the design of teaching strategies based on conceptual conflict.

Keywords: Conceptual representations, heat, temperature, pre-service teachers, elementary school.

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365 Direct Numerical Simulation of Oxygen Transfer at the Air-Water Interface in a Convective Flow Environment and Comparison to Experiments

Authors: B. Kubrak J. Wissink H. Herlina

Abstract:

Two-dimensional Direct Numerical Simulation (DNS) of high Schmidt number mass transfer in a convective flow environment (Rayleigh-B'enard) is carried out and results are compared to experimental data. A fourth-order accurate WENO-scheme has been used for scalar transport in order to aim for a high accuracy in areas of high concentration gradients. It was found that the typical spatial distance between downward plumes of cold high concentration water and the eddy size are in good agreement with experiments using a combined PIV-LIF technique for simultaneous and spatially synoptic measurements of 2D velocity and concentration fields.

Keywords: Air-Water Interface, DNS, Gas Transfer, LIF.

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364 Genetic Variants and Atherosclerosis

Authors: M. Seifi, A. Ghasemi, M. Khosravi, M. Salimi, S. Jahandideh, J. Sherizadeh, F. S. Hashemizadeh, R. Khodaei

Abstract:

Atherosclerosis is the condition in which an artery wall thickens as the result of a build-up of fatty materials such as cholesterol. It is a syndrome affecting arterial blood vessels, a chronic inflammatory response in the walls of arteries, in large part due to the accumulation of macrophage white blood cells and promoted by low density (especially small particle) lipoproteins (plasma proteins that carry cholesterol and triglycerides) without adequate removal of fats and cholesterol from the macrophages by functional high density lipoproteins (HDL). It is commonly referred to as a hardening or furring of the arteries. It is caused by the formation of multiple plaques within the arteries.

Keywords: Arterial blood vessels, atherosclerosis, cholesterol.

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363 Numerical Analysis for the Performance of a Thermoelectric Generator According to Engine Exhaust Gas Thermal Conditions

Authors: Jinkyu Park, Yungjin Kim, Byungdeok In, Sangki Park, Kihyung Lee

Abstract:

Internal combustion engines rejects 30-40% of the energy supplied by fuel to the environment through exhaust gas. thus, there is a possibility for further significant improvement of efficiency with the utilization of exhaust gas energy and its conversion to mechanical energy or electrical energy. The Thermo-Electric Generator (TEG) will be located in the exhaust system and will make use of an energy flow between the warmer exhaust gas and the external environment. Predict to th optimum position of temperature distribution and the performance of TEG through numerical analysis. The experimental results obtained show that the power output significantly increases with the temperature difference between cold and hot sides of a thermoelectric generator.

Keywords: Thermoelectric generator, Numerical analysis, Seebeck coefficient, Figure of merit

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362 Advanced Compound Coating for Delaying Corrosion of Fast-Dissolving Alloy in High Temperature and Corrosive Environment

Authors: Lei Zhao, Yi Song, Tim Dunne, Jiaxiang (Jason) Ren, Wenhan Yue, Lei Yang, Li Wen, Yu Liu

Abstract:

Fasting dissolving magnesium (DM) alloy technology has contributed significantly to the “Shale Revolution” in oil and gas industry. This application requires DM downhole tools dissolving initially at a slow rate, rapidly accelerating to a high rate after certain period of operation time (typically 8 h to 2 days), a contradicting requirement that can hardly be addressed by traditional Mg alloying or processing itself. Premature disintegration has been broadly reported in downhole DM tool from field trials. To address this issue, “temporary” thin polymers of various formulations are currently coated onto DM surface to delay its initial dissolving. Due to conveying parts, harsh downhole condition, and high dissolving rate of the base material, the current delay coatings relying on pure polymers are found to perform well only at low temperature (typical < 100 ℃) and parts without sharp edges or corners, as severe geometries prevent high quality thin film coatings from forming effectively. In this study, a coating technology combining Plasma Electrolytic Oxide (PEO) coatings with advanced thin film deposition has been developed, which can delay DM complex parts (with sharp corners) in corrosive fluid at 150 ℃ for over 2 days. Synergistic effects between porous hard PEO coating and chemical inert elastic-polymer sealing leads to its delaying dissolution improvement, and strong chemical/physical bonding between these two layers has been found to play essential role. Microstructure of this advanced coating and compatibility between PEO and various polymer selections has been thoroughly investigated and a model is also proposed to explain its delaying performance. This study could not only benefit oil and gas industry to unplug their High Temperature High Pressure (HTHP) unconventional resources inaccessible before, but also potentially provides a technical route for other industries (e.g., bio-medical, automobile, aerospace) where primer anti-corrosive protection on light Mg alloy is highly demanded.

Keywords: Dissolvable magnesium, coating, plasma electrolytic oxide, sealer.

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361 An Investigation of the Cu-Ni Compound Cathode Materials Affecting on Transient Recovery Voltage

Authors: Arunrungrusmi S, Chaokamnerd W, Tanitteerapan T, Mungkung N., Yuji T.

Abstract:

The purpose of this research was to analyze and compare the instability of a contact surface between Copper and Nickel an alloy cathode in vacuum, the different ratio of Copper and Copper were conducted at 1%, 2% and 4% by using the cathode spot model. The transient recovery voltage is predicted. The cathode spot region is recognized as the collisionless space charge sheath connected with singly ionized collisional plasma. It was found that the transient voltage is decreased with increasing the percentage of an amount of Nickel in cathode materials.

Keywords: Vacuum arc, Instability, Low current, Cathode spot, copper, Nickel, Transient Recovery Voltage.

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360 Multiphase Coexistence for Aqueous System with Hydrophilic Agent

Authors: G. B. Hong, H. W. Chen

Abstract:

Liquid-Liquid Equilibrium (LLE) data are measured for the ternary mixtures of water + 1-butanol + butyl acetate and quaternary mixtures of water + 1-butanol + butyl acetate + glycerol at atmospheric pressure at 313.15 K. In addition, isothermal vapor–liquid–liquid equilibrium (VLLE) data are determined experimentally at 333.15 K. The region of heterogeneity is found to increase as the hydrophilic agent (glycerol) is introduced into the aqueous mixtures. The experimental data are correlated with the NRTL model. The predicted results from the solution model with the model parameters determined from the constituent binaries are also compared with the experimental values.

Keywords: LLE, VLLE, hydrophilic agent, NRTL.

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