bluuebunny/crossref_metadata_2025_split huggingface dataset:
Shape Memory Alloys and Their Applications in Power Generation and Refrigeration
Authors: Cui Jun 
Published: December 2013

ABSTRACTThe shape memory effect is closely related to the reversible martensitic phase transformation, which is diffusionless and involves shear deformation. The recoverable transformation between the two phases with different crystalline symmetry results in reversible changes in physical properties such as electrical conductivity, magnetization, and elasticity. Accompanying the transformation is a change of entropy. Fascinating applications are developed based on these changes. In this paper, the history, fundamentals and technical challenges of both thermoelastic and ferromagnetic shape memory alloys are briefly reviewed; applications related to energy conversion such as power generation and refrigeration as well as recent developments will be discussed.
Adventures with a Flipped Classroom and a Materials Science and Engineering MOOC : “Fools Go Where Angels Fear to Tread”
Authors: Clemens Bruce M. , Nivargi Chinmay , Jan Antony , Lu Yuxiang , Schneider Emily , Manning Jane 
Published: December 2013

ABSTRACTIn the fall of 2012 the Stanford University materials science course Solar Cells, Fuel Cells and Batteries: Materials for the Energy Solution was offered as a flipped class and a massively open online course (MOOC). To the best of our knowledge, this was the first materials science MOOC. Here we describe how the course was implemented, and present results on performance, demographics and other observations that were made. Finally, we provide some perspectives for the future of the implementation of these engineering MOOCs.
Photocatalytic Activity of Bare and Amine-Treated TiO2 Nanoparticles
Authors: Hossain Fahim , Perez Oscar Perales , Hwang Sangchul 
Published: December 2013

ABSTRACTThe capability of tuning the functional properties of nanosize TiO2 nanoparticles (NPs) by suitable control of surface chemistry, phase stability and crystal size plays a key role on their safe use and enhanced efficacy in actual and envisioned applications, including nanomedicine, environmental remediation, and food safety, among others. On this basis, any attempt to develop a size-controlled synthesis method and an efficient surface treatment protocol becomes indispensable. Accordingly, we have synthesized TiO2 NPs via a modified aqueous processing route using HNO3 as a catalyst and polyvinylpyrrolidone as particle size controller and a dispersing agent. The NPs surface was treated by using Ethylenediamine (EDA) as a source for amine species. Bare and amine-treated TiO2 NPs were characterized by X-ray diffraction (XRD) and FTIR spectroscopy. The photocatalytic activity of TiO2 NPs was assessed by irradiating an aqueous solution of Methylene Blue (MB) dye containing different amounts of the NPs. XRD analyses evidenced the formation of two phases of crystalline TiO2 with an average crystallite size estimated at 15.3 nm. Bare and amine-treated TiO2 NPs exhibited significant activity under UV light illumination (365 nm). Bare NPs exhibited a dye photo degradation capability of about 38.02% with particle concentration of 0.5 g/l while amine-treated NPs reported 66.18% dye photo degradation capability with particle concentration of 0.5 g/l.
Effect of the Nature of the Metal Co-Catalyst on CO2 Photoreduction Using Fast-Grown Periodically Modulated Titanium Dioxide Nanotube Arrays (PMTiNTs)
Authors: Amirsolaimani Babak , Zhang Xiaojiang , Han Fei , Farsinezhad Samira , Mohammadpour Arash , Dechaine Greg , Shankar Karthik 
Published: December 2013

ABSTRACTAnodically formed TiO2 nanotube arrays composed of the anatase phase with periodically modulated diameters (PMTiNTs) are excellent photocatalysts for the sunlight-driven transformation of carbon dioxide into hydrocarbons. Exploiting the full potential of this nanoarchitecture for CO2 photoreduction requires integration with metal nanoparticles that function as catalytic promoters for multistep electron transfer reactions. We studied the effect of different metallic and bimetallic nanoparticles on the rate of generation of light hydrocarbons by the photoreduction of CO2. All the metal nanoparticles were loaded on to the TiO2nanotubes using the technique of photodeposition, which standardized the coating process and enabled examination purely of the effect of different metals. Photodeposition was used not only due to its simplicity but also because it enabled us to engineer very fine coatings possessing excellent uniformity and depth penetration into the nanotubes. The best performing co-catalysts were found to be CuPt (atomic ratio of 0.33:0.67), Pt and NiPt (1:2), which when loaded onto the PMTiNTs yielded total hydrocarbon generation rates of 3.5, 0.85 and 0.8 mL g-1 hr-1 respectively. The time required to form PMTiNTs was reduced by a factor of 160 by using a recently reported recipe based on fluoride ion bearing electrolyte containing lactic acid. PMTiNTs formed using the ultrafast growth lactic acid-based electrolytes exhibited similar photocatalytic properties to samples obtained more slowly using conventional ethylene glycol-based electrolytes.
A Highly Efficient On-chip 3D Plasmonic Nanofocusing Structure
Authors: Kim Myung-Ki , Choo Hyuck 
Published: December 2013

ABSTRACTWe demonstrate and analyze a highly efficient on-chip 3D metal-insulator-metal (MIM) nanofocusing structure. Here, we show the in-depth theoretical design, analysis and discussion to provide a detailed picture of the highly efficient, on-chip nanofocusing process which is linearly tapered in 3D.
Mechanical Characterisation of the NiTi Shape Memory Alloy for Microfluidic Valve Applications
Authors: Waddell Alistair M. , Punch Jeff , Stanley Walter , Jeffers Nicholas , Stafford Jason 
Published: December 2013

ABSTRACTPhotonics Integrated Circuits (PICs) are being applied by the telecommunications industry as transceivers for fibre optic networks. The core component of a typical PIC is the laser array and these devices can have relatively low operating temperatures (15°C - 25°C) with a tight operating range (±0.1K). To accommodate such a specification, a thermal control system is required that can change the cooling rate through feedback. The power density of next generation PICs is at such a level to demand novel thermal management architectures including developments such as near source liquid cooling. In order to control the thermal performance of fluidic devices, effective methods for varying the rate of coolant are an essential component. Consequently, micro-valve structures are required, ideally involving passive actuation to meet stringent reliability standards. One solution to this challenge is to exploit the phase-change driven shape memory effect of the NiTi Shape Memory Alloy (SMA). A micro-valve could be developed from the NiTi SMA, thermally coupled to the laser array component in order to work passively to regulate the flow of coolant in a micro-channel. Such a valve would have to be intrinsically reliable, and the goal of this paper is to investigate the conditions that will affect this reliability. The objective of the work is to investigate the mechanical properties relevant to the design of a passive NiTi SMA micro-valve, with a focus on the formation of stress-induced Martensite bands. It is not understood why these bands form on a plane inclined at ∼55° to the axis of loading and in this paper theory is presented that suggests a reasoning for this. A plate sample of NiTi was tested in uni-axial tension and Digital Image Correlation (DIC) used to analyse the strain fields across the surface of the sample. The DIC results revealed areas of high stress concentrations occurring in bands inclined on average 53.86° to the axis of loading. The theory and experimental observations are in agreement with the literature but to validate the theory the crystal texture needs to be analysed in the stress concentration regions. This paper provides valuable insight into the mechanical behaviour of a passive NiTi SMA micro-valve subjected to a sufficient pressure to form stress-induced Martensite.
Ab initio study of magnetic properties of Fe-Mn-Al Heusler alloys
Authors: Sokolovskiy Vladimir V. , Buchelnikov Vasiliy D. , Zagrebin Mikhail A. , Taskaev Sergey V. , Khovaylo Vladimir V. , Entel Peter 
Published: December 2013

ABSTRACTDensity functional theory (DFT) based on the spin-polarized relativistic Korringa-Kohn-Rostoker (SPR-KKR) method is used to investigate the magnetic properties of nonstoichiometric Fe2+xMn1-xAl Heusler alloys, where 0 ≤ x ≤ 0.9. The composition dependences of the magnetic exchange couplings and the Curie temperature for the cubic L21 phase are obtained. Our simulations have shown that the Fe-Fe nearest neighbors present a strong ferromagnetic coupling. Moreover, these exchange interactions are larger than other interactions. The substitution of Mn by Fe in Fe2+xMn1-xAl (0 ≤ x ≤ 0.9) leads to an increase in the Curie temperature. This tendency and the values of Curie temperatures are in agreement with the experimental results for Fe2+xMn1-xAl (x = 0, and 0.1). The highest Curie temperature was observed for the Fe-richer alloy.
The Supercell Scaling Investigation of Magnetic Properties in Ni-Mn-X (X=Ga, In, Sn, Sb) Heusler Alloys by Means of First-principles Methods
Authors: Buchelnikov Vasiliy , Sokolovskiy Vladimir , Zagrebin Mikhail , Taskaev Sergey , Khovaylo Vladimir , Entel Peter 
Published: December 2013

ABSTRACTIn this work we study the influence of supercell scaling on magnetic properties in Ni-Mn-X-Z alloys by means of ab initio calculations with the help of Quantum Espresso PWSCF package and the spin-polarized relativistic Korringa-Kohn-Rostoker (SPR-KKR) code based on DFT approximation. It is shown that the supercell calculations for the equilibrium lattice parameter are coincided with the calculations for simple primitive lattice. The exchange parameters for Ni-Mn-X alloys obtained from supercell calculations are large than calculated for simple primitive lattice.
Integration of Dielectric Dispersion and 3D NMR Characterizes the Texture and Wettability of a Cretaceous Carbonate Reservoir
Authors: Abdelaal Atef Farouk , Al Daghar Khadija Ahmed , Ramamoorthy Raghu , Brahmakulam Jacob , Hall Jonathan C. , Baguenane Boussad , Al Marzooqi Mohammed Bin , Faivre Ollivier 
Published: December 2013

Abstract
Knowledge of rock texture and wettability are vital for the static and dynamic description of carbonate reservoirs. Conventional log measurements are limited in their applicability for the quantitative assessment of these attributes. Rapid variations of texture in carbonates diminishes the usefulness of core measurements on samples of limited size. Obtaining representative relative permeability by restoring core to native reservoir conditions, especially the original wettability state, is also very challenging.
The dielectric response of clean carbonate rocks exhibit characteristic frequency dispersion patterns which depend on their texture and wettability. Dielectric measurements with multiple frequencies have become available enabling us to extract this information by inverting the tool data using a dispersive petrophysical model.
The dielectric response is primarily sensitive to water, and provides a measure of the water phase tortuosity, which is a combination of texture and wettability, captured in the Archie’s exponents m and n. Previous work has demonstrated the estimation of m from pore size distribution obtained from NMR data using an effective medium model. Formation Resistivity Factor data from core is presented to validate the model-derived m. In this work we propose a way to combine the cementation exponent so derived with the textural answers from the dielectric measurement to make a wettability estimate. We also assess the wettability from 3D NMR stations, using the increase in relaxation of oil manifested as shortening of the oil T2 signal due to partial wetting of the oil phase.
The methods are illustrated on a dataset from a Cretaceous carbonate, onshore Abu Dhabi. The interval surveyed in the subject well straddles an oil/water contact (OWC). The n exponent value derived by the method shows that the rock above the OWC is oil-wet in varying degrees. The inference on wettability state from the NMR data further supports the conclusions.
Field Experience with Still Pipes Installation and Supporting in KOC Storage Tanks
Authors: Nassar Raga Hanna , Al-Hajri Abdul Rahman 
Published: December 2013

Abstract
In continuation with the efforts being done to achieve accurate liquid measurement performance at tank farms and to empower the commitment towards protecting the Company’s net worth, high level of accuracy must be achieved when conducting manual and/or automatic measurement of the basic variables required for the determination of the net liquid asset at any time; i.e., level, temperature, density, free water, mass, amongst others. In this line and with the aim of maximizing the overall accuracy of the installed Automatic Tank Gauging (ATG) system by reducing the effects caused by installation and operating conditions, an initiative has been implemented to upgrade the installation and supporting of the still pipe were the ATG is mounted and that of the official manual tank gauging (OMTG) still pipe utilized to verify the accuracy of the ATG. As a result of this initiative, minimal or no vertical movement of the ATG mounting location has been recorded and more stable ATG verification test results are obtained nowadays, enabling the reduction of radar calibrations basically enforced by this mounting movement. This paper will examine the operational problems faced with the design principles considered for the ATG installation on the new and existing storage tanks in KOC and provides recommendations to overcome/minimize the impact of these issues on the liquid measurements process.
Application of a New Integrated Technique for Servo Adjustable Water Detection and Water Shuto ff in Sudan Oilfield
Authors: Fuwei Zhong , Dekui Xu , Xiaohui Han , Xiaoyu Xu , Zhongchao Lin , Yuan Gao , Wenlin Xu , Xiaojing Zhang , Fei Gao , Rongxi Li 
Published: December 2013

Abstract
The Block 3/7 of Sudan Oilfield has been in the period of high water production. The water cut of many wells is more than 80%, and still rising. Besides, there are many sandy wells in this area. In order to reduce the water cut, the conventional technique involves two string trips—water detection primarily, and then water shutoff treatment according to the result of testing. Obviously, high cost and low efficiency restrict its application. Therefore, based on the conventional technique, a new integrated technique for servo adjustable water detection and water shutoff has been researched by Daqing Oilfield Limited Company, which is mainly made up of drillable packers to divide layers, intelligent controlled piezoelectric valves, inserted seal sections and releasing subs. With the integrated technique, dynamic adjustment and water shutoff treatment can be achieved at any layer without pulling the string upward or downward. Applying casing pressure signals can open the appointed position’s valve when detecting water, then get its single layer’s production, meanwhile record and test on the ground to confirm this layer’s production and water cut. Applying casing pressure signals closes the appointed position valve after testing. Repeating the above steps can get all the layers water production and water cut. According to the result of water detection test, open the intelligent controlled piezoelectric valves of the lower water cut layers to stabilize the oil production.
This new technique has been successfully applied to 8 wells in the Block 3/7 of Sudan Oilfield, which features low cost and high efficiency. It could meet the requirements of water detection and water shutoff for the remaining 30 wells of high water production. Similarly, it could apply to many wells of high water production in Daqing Oilfield.
Modeling, Simulation and Comparison of Common Control Techniques of AC Induction Motor Drive
Authors: Al-Khaledi Sadoun , Al-Qallaf Ahmad 
Published: December 2013

Abstract
AC induction motor drives are now finding increasing acceptance in various industrial applications because of the performance they can provide. Applications of AC drives vary from running simple conveyor belts and blowers to implementing a sophisticated variable speed variable frequency drives (VFD), in which torque and speed are wellregulated. Based on the type of application, choice of an appropriate control technique is made.
This paper presents a comparative study on most popular control strategies of Induction Motor Drives; constant V/Hz open/ closed loop control, field-oriented control (FOC), and Direct Torque Control (DTC).
The comparison is based on various criteria including basic control characteristics, torque performance, speed performance and transient response with respect to the load torque and speed variations.
Simulations of the above control techniques have been performed using MATLAB/SIMULINK™ software.
The Adjustable Speed Drives are generally used in industry. In most drives AC motors are applied. The standard in those drives are Induction Motors (IM). Induction motors are widely used in application such as pumps, fans, elevators, electrical vehicles, heating, ventilation and air-conditioning (HVAC), robotics, wind generation systems, etc.
Previously, DC machines were preferred for variable speed drives. However, DC motors have disadvantages of higher cost, higher rotor inertia and maintenance problem with commutators and brushes. In addition they cannot operate in dirty and explosive environments. The AC motors do not have the disadvantages of DC machines. Therefore, DC motors are progressively replaced by AC drives. The accountable for those results are the development of modern semiconductor devices, especially power insulated gate bipolar transistors (IGBT).
The most economical IM speed control methods are realized by using frequency converters. Many different strategies of frequency converters are proposed and investigated in this paper. However, a converter consisting of a diode rectifier, a dc-link and a pulse width modulated (PWM) voltage inverter is the most applied used in industry.
The high-performance frequency controlled PWM inverter – fed IM drive should be characterized by: Fast flux and torque response.Constant switching frequency.Low flux and torque ripple.Robustness for parameter variation.
The abovesaid features depend on the applied control strategy. The main goal of the chosen control method is to provide the best possible parameters of the drive. Additionally, a very important requirement regarding control method is the simplicity (simple algorithm, simple tuning and operation with small controller dimension leads to low price of final product).
A general classification of the variable frequency IM control methods is presented in Fig. 1
Corrosion Monitoring for Kuwait’s Pipeline Network System
Authors: Al-Shamari A. , Al-Sulaiman S. , Al-Mithin A. , Jarragh Amer , Prakash S. S. 
Published: December 2013

ABSTRACT
Kuwait is the 5th largest oil producer in the world with a current crude oil production represents about 9% of the world’s oil. The country’s goal is to increase the production through the Strategic Plan 2020 and the Strategic Plan 2030. The Kuwait Oil Company (KOC) is the primary national organization responsible for exploration, drilling, production a- processing of the crude. The number and length of crude pipelines as well as the pipelines for other products (condensate, gas and water) have cumulatively grown to become about 4750 km over the last 60 years.
In-line inspection (ILI) pigging data has indicated internal corrosion damages in some pipelines. In addition, corrosion probes and coupons data along with fluid and bacteria analyses from various locations have confirmed internal corrosion damage. Therefore, a comprehensive Corrosion Management Plan for the Pipeline Network System has been established involving the following: (a) installation of internal corrosion monitoring equipment, (b) external corrosion protection by using coatings and cathodic protection (CP), (c) periodic cleaning pigging operations for internal cleaning, and (d) conducing in-line inspection (ILI).
The present paper will discuss the salient features of the Internal Corrosion Management Plan and its implementation in crude pipeline network.
The Impact of Black Powder on Gas Plant Safety Relief Valve Isolation Valve
Authors: Al-Jumayiah Khalid Abdullah 
Published: December 2013

Abstract
Black powder is a common problem in any upstream gas facilities. Black powder causes many problems to the gas treating facility. These problems can be in a form of erosion of gas transportation pipeline, erosion of processing equipment such as gas compressor, impurities in the product and accumulation in flow reduction components and clogging on isolation valves. This all leads to upsetting gas plant operation resulting in numerous cost to restore the plant operation and resolve the problem. One of the critical equipment that encounter black powder problem is isolation valve of safety relief valve. As known, safety relief valves are among the critical equipment in any plant. Safety relief valves are usually installed with an upstream block valve to maintain the operation and facilitate maintenance of the safety relief valve. Therefore, failure of this critical isolation valve will cause difficulties when dismantling the isolation valve as black powder will get accumulated in the cavity area of the valve and damage the seating which will, in turn, prevent full closure of the isolation valve. Realizing this detrimental effect of black powder on isolation valve entails proper selection process of isolation valve type. Nowadays, the industry offers various type of isolation valve. Each type has its own design aspects in terms of the capacity, strength, operator and nature of fluid media. However, the long term reliability comes from experience when valve is put into service. Under black powder operation conditions, passing or leaking after short period of time of operation usually not a good sign of proper valve selection. That is why emphasis have to be given to understand the nature of the processed product and select the right type of isolation valve that will serve for a long time to insure plant safety, reliability and smooth operation. In this paper, a Saudi Aramco gas plant experience will be shared of black powder problem on isolation gate valve of safety relief valve and the remedial action that has been taken to rectify this repeated problem.