bluuebunny/crossref_metadata_2025 huggingface dataset:
Structural and Electrical Properties of Silver-Doped Zinc Oxide Nanorods Array
Authors: Lee Shih Fong , Lee Li Ying , Chang Yung Ping
Published: April 2015

In this study, silver-doped zinc oxide (ZnO) nanorods were grown by a solution method and the effect of varying the doping concentration on the electrical property and component characteristics of the synthesized ZnO nanorods were studied. The ZnO nanorods were grown in the mixed solution of zinc nitrate hexahydrate (Zn (NO3)2·6H2O), hexamethylenetetramine (C6H12N4), and silver nitrate (AgNO3) at 90oC for 2 hours. The purpose of silver nitrate was to supply dopant atoms. Field-emission scanning electron microscopy (FE-SEM), energy dispersive spectrometer (EDS), X-ray diffraction (XRD) were used to investigate the surface morphology, chemical compositions, and microstructure of silver-doped ZnO nanorods, and the electrical properties were determined by Hall effect measurement. As found by EDS results, dopant atoms Ag have been successfully incorporated into the crystalline structure of ZnO nanorods, and the conductivity, concentration and mobility of majority carrier in ZnO nanorods have been modified accordingly.
Influence of Ingate Thickness and Pouring Temperature on Structure and Fluidity of Cast Hyper-Eutectic Al-18%Si Alloy
Authors: Ramadan Mohamed
Published: April 2015

The flow of molten metal after being poured usually is accompanied by turbulence, splashing, separation of streams near change of sections, branching off and rejoining of streams, changes in melt properties such as density, viscosity, surface tension and the solidification behavior. In this work, the effect of gating design (ingate thickness) and pouring temperature on the microstructure and fluidity of Al-18% Si alloy into sand mold are investigated. Four different ingates thicknesses of 2.5, 3, 3.5 and 4mm are used. The melt charge was poured at three different pouring temperature (680, 670, 660 °C) into the mold. Decreasing the ingate thickness slightly improves the microstructure to be fine and more globular. Decreasing the ingate thickness increases the hardness of all cast samples. Increasing the pouring temperature increases the filling area of cast Al-18% Si alloy for all ingates thicknesses used in this study. To maintain complete filling for pouring temperatures of 670 °C and 660 °C a minimum of 3.5 and 4 mm ingate thicknesses consequentially should be considered.
A First Principle Study of the Massive TMR in Magnetic Tunnel Junction Using Fe3Al Heusler Alloy Electrodes and MgO Barrier
Authors: Rotjanapittayakul Worasak , Archer Thomas , Sanvito Stefano , Pijitrojana Wanchai
Published: April 2015

The massive tunnel magnetoresistane (TMR) is expected when Fe3Al Heusler alloy are used for magnetic electrodes in magnetic tunnel junction (MTJ). We demonstrate the Fe3Al/MgO/Fe3Al MTJ, which have good lattice matching interfaces. The electronic and transport properties of these system are systematically investigated by first principle calculation. The electronic band structure of Fe3Al Heusler alloy and MgO are represented for discussion spin filtering effect. Besides, the transmission conductance is calculated to study the spin tunneling effect. We found that the massive TMR is clearly achieved at zero-bias condition, and the TMR is decreased when the finite bias are applied. Thus, among ferromagnetic materials, the Fe3Al Heusler alloy will be good alternative to bcc-Fe based electrodes with MgO barrier for the MTJs beyond.
Influences of Temperature and Strain Rate on Microstructure of Manganese Aluminum Bronze Alloy
Authors: Wannaprawat Nuwan , Suranuntchai Surasak , Thuanboon Swieng , Uthaisangsuk Viton
Published: April 2015

Manganese Aluminum Bronze has been extensively used for applications under seawater such as marine propellers, because this alloy exhibits high strength as well as excellent corrosion resistance behavior. In this work, microstructures and hardness properties of an as cast Manganese Aluminum Bronze undergoing hot deformation at different temperatures between 700oC, 750oC, 800oC and 850oC with the strain rates of 0.1s-1 and 1s-1 were investigated. Microstructures of the MAB alloy from each condition were characterized by both optical and scanning electron microscopy. The results showed that dynamic recrystallization obviously occurred at the temperatures higher than 800oC for both strain rates. Finally, determined hardness values were correlated with observed microstructure evolutions.
Novel β- Cyclodextrin Functional Monomers and its Application for Molecularly Imprinted Polymers
Authors: Feng Feng , Liu Zhi Min , Xu Zhi Gang
Published: April 2015

β-Cyclodextrin shows good molecular recognition ability for its unique physical and chemical properties and suitable cavity structure. The selective recognition can be further improved if β-cyclodextrin combines with molecularly imprinted technique. In this paper, the novel β-cyclodextrin functional monomers were introduced. And the preparation and application of molecularly imprinted polymers based on β-cyclodextrin functional monomers were reviewed. The development trend of β-cyclodextrin molecularly imprinted polymers were also prospected.
Synthesis of Magnesium Based Layered Hydroxide Salt and its Chemical Heat Storage Properties
Authors: Yamashita Seiji , Sugie Yoshimasa , Kita Hideki
Published: April 2015

A chemical heat storage method is advantageous in terms long periods of time storage and the high storage density are possible as compared to the direct storage methods. Normally, a reversible single reaction is utilized, then the heat storage temperature is limited. On the other hand, in order to store industrial waste ranging widely in the temperatures, it’s necessary to develop a new material which allows heat storage in a stepwise manner in response to temperature changes. In this study, we have investigated the effect of several experimental conditions on the synthesis of Mg based layered hydroxide by simple aqueous solution derived methods. In addition, the potentials of the multistep chemical heat storage property have been investigated.
Development of the Synthesis of Chromium and Molybdenum – Amino Acid Complexes: A Green Chemistry Approach
Authors: Budiasih Kun Sri , Anwar Chairil , Santosa Sri Juari , Ismail Hilda
Published: April 2015

Some concepts of green chemistry were applied on the Synthesis of Chromium(III) and Mo(V) complexes with amino acids. Three concepts were used in this research were changing to safer solvent, using less energy and appliying a shorter process. The optimum pH of the complex formation of Chromium (III) is 4, whereas for Mo(V) complex, the most stable condition is at pH=1. The products were characterized by physical properties, Infrared and Uv-Vis spectrophotometer, Atomic Absorbtion Spectrophotometer, Elemental Analysis, and VSM (Vibrational Sample Magnetometer). The molecular formula of the complexes were predicted by simulation from the composition and the magnetic properties.
Model of Phanerochaete chrysosporium Growth and Multisubstrate Degradation on the Biological Pretreatment of Water Hyacinth
Authors: Sari Eka , Syamsiah Siti , Sulistyo Hary , Hidayat Muslikhin
Published: April 2015

A mathematical model was developed to predict the kinetics of Phanerochaete Chrysosporium growth and degradation of multisubstrate on a batch process with limited oxygen conditions, that of the effects the initial moisture content (IMC). The study was conducted on the pretreatment of water hyacinth (WH), to degrade the lignin in order to prepare the WH as a bioethanol feedstock. In this pretreatment, the fungus was inoculated on WH where it grew on the surface of the WH. The fungus consumed three different substrates contained in WH as carbon source, i.e. lignin, cellulose and hemicellulose. Experimental data are used to formulate multisubstrate degradation and fungal growth influenced by the IMC. The constant of fungal growth (μ) is influenced by the amount of the initial moisture content (IMC) following the equation with μmax value of 0.6887 day-1, KSL reached 0.7967 g.g dry weight-1, KsS is 0.7102 g.g dry weight-1, KsH is 0.1965 g.g dry weight-1, Yx/sL is 0.13 g.g dry weight of lignin-1, Yx/sS is 0.8560 g.g dry weight of cellulose-1, Yx/sH is 0.8999 g.g dry weight of hemicellulose-1 and the maximum of IMC (Wm) is 0.67 or 67%.
Adsorption of Remazol Brilliant Blue R (RBBR) by C-4-Ethoxy-3-Methoxyphenylcalix[4]Resorcinarene Triphenylphosphonium Chloride
Authors: Wulandari Rika , Jumina Jumina , Siswanta Dwi
Published: April 2015

The adsorption of Remazol by CEMPCRP was studied as a function of pH, contact time and concentration. All experiments were carried out using the batch method. The initial and final RBBR concentration were determinated using UV-Vis spectrometer at λ = 592.3 nm. The result showed that the optimum condition of RBBR adsorption were at pH 10, contact time 360 min, and concentration of 300 mg/L. This adsorption followed the Lagergren (first pseudo order) and Langmuir isotherm adsorption model. The adsorption capacity was obtained 6.51 x 10-5 mol/L and the mechanism is a chemisorption (ΔG = 28.92 kJ/mol) that occurs in the monolayer.
Effects of Anti-Clogging in Ultra-Soft Soils Using Different Composite Filter Material
Authors: Zhou Yuan , Zhang Ling Yun , Lu Zhi Hao
Published: April 2015

An experimental study on drainage of different composite filter material in Wenzhou ultra-soft soils was carried out, to investigate the effects of anti-clogging for these composite material. A new instrument was designed to simulate draining process of the ultra-soft soils under vacuum loadings. Based on the experimental results in the form of pump quantity of water, the average settlement of the sludge, the pumping rate and the water content, a comparison was made among six composite filter material (e.g., PVA-1, PVA-2, SAP, superfine fiber, coral cashmere fiber and bamboo fiber) and a traditional non-woven fabric material. The results demonstrate that, PVA-2 composite material is the best way to keep from clogging in the ultra-soft soils. The effects of the anti-clogging is depended on the characteristics of the water absorbency and retention.
Experimental Investigation of Mueller Matrix of a Bidispersed Foam Using Polarised Light Scattering
Authors: Qian Shao Yu , Chen John J.J.
Published: April 2015

We have previously investigated foams with monodispersed bubbles using a polarised light scattering technique. The liquid fraction and the bubble size distribution were found to influence scattering properties of polarised light and correlate with the Mueller matrix elements. This paper focused on an investigation of the Mueller matrix of a bidispersed foam. Comparisons were made between the results of bidispersed foam and monodispersed foam.
Graphene Based Polymer Strain Sensors for Non-Destructive Testing
Authors: Deepak A. , Srinivasan N. , Karthik V. , Ramya S. , Ganesan Vaidehi , Shankar P.
Published: April 2015

This work reports the possibility of using graphene based polymer nanocomposites for strain sensing applications. The Graphene-PVDF composite films were characterized using techniques like Scanning Electron Microscope, X-ray Diffraction and Raman analysis. Dielectric studies were carried out to check the conductivity of the nanocomposite film as a function of different weight percentage of graphene. The output voltage variation in Graphene-PVDF based films, as a function of strain, were correlated with digital image correlation (DIC) technique.
The Effect of Thermal Cycling on the Agglomeration of Fuel Cell Electrocatalysts
Authors: Wongyao Nutthapon , Therdthianwong Apichai , Therdthianwong Supaporn
Published: April 2015

The effect of thermal cycling on the agglomeration within 48 hrs of Pt and PtRu electrocatalysts was investigated by using transmission electron microscopy (TEM) and X-ray diffraction (XRD). In comparison with the thermal continuous test, particle agglomeration under the thermal cycle condition was more severe. The PtRu particle size increment was 44.4% and 70.4% for thermal continuous and thermal cycle tests, respectively. These results are in agreement with the direct methanol fuel cells (DMFC) performance test. In the study of the effect of environment, the ethanol solution caused the highest Pt particle agglomeration, followed by methanol and water.
The Preparation of Fluorocarbon Thermal Insulation Coating with Different Fillers
Authors: Ye Xiu Fang , Chen Dong Chu , Chang Meng Lei , Liang Qi Hua , Lu Qi Peng
Published: April 2015

According to the mechanism of thermal insulation, closed pore perlite, hollow glass microsphere and nanoantimony tin oxide (ATO) powder three different kinds of functional fillers were adopted respectively to prepare obstructive, reflective and radiative thermal insulation coating base on polyvinylidene fluoride emulsion, and how the category and content of functional fillers effect the thermal insulation performance of the fluorocarbon thermal insulation coating (FTIC) was investigate. The test results showed that, all the three functional fillers has an significant effect on the thermal insulation performance of FTIC.
Parametrical Investigations on Concrete-Jacketed RC Columns with Pre- and Post-Corrosion Damage
Authors: Wang Sai Sai
Published: April 2015

The main objective of this study is to parametrically investigate the effect of pre-and post-corrosion and loading damage on concrete-jacketed reinforced concrete (RC) columns under uni-axial loading. A model capable of evaluating the squash load of un-jacketed or jacketed RC columns with and without corrosion damage was induced. The parametric studies based on this model are meant to investigate the effect of rebar corrosion on the axial compression capacity of jacketed RC column. It was concluded that the longitudinal rebar corrosion has more distinct effect on the peak load than that of web rebar. The jacketing rebar corrosion has more distinct effect on the peak load than that of substrate rebar.
Development of Vacuum Levitation Melting Technology in China
Authors: Li Bei , Zhang Sen , Xu Jie Ping , Zhang Wei
Published: April 2015

This paper reviews the development of levitation melting technology including the equipment production, fundament research and applied development from 1981 to 2012, moreover, introduces the new progresses after 2010 from different aspects including improved levitation ability, increased melting temperature, increased equipment specification, and combining levitation melting with modern technologies of the material science, and so on. The development of advanced materials preparation by using levitation melting technology also is introduced in this paper.
Dissimilar Welding Simulation of 316L and Low Alloy Steel Using the SYSWELD Simulation
Authors: Liu Ying Cheng , Cheng Ta Chien , Yu Chieh , Shiue R.K.
Published: April 2015

The purpose of this investigation is focused on the welding process simulation using the SYSWELD software. It has been used to conduct the simulation of the tungsten inert gas (TIG) welding process. 316L stainless steel (316L SS) is welded with a low alloy steel (A508) using the Inconel filler 82 (IN-82). Welding experiments are carried out in order to compare with simulation results. Profile of the welding pool, residual thermal stress and deformation of the weld have been studied, and accuracy of the simulated results is also evaluated.
Constitutive Modeling of Flow Stress of MAB Alloy
Authors: Aungsusiripong Auchariya , Suranuntchai Surasak , Uthaisangsuk Viton
Published: April 2015

In this work, plastic flow behavior of an as-cast manganese aluminum bronze was investigated under various compressive deformation conditions. The forming temperatures of 1023, 1073, 1123 and 1173 K and strain rates of 0.01, 0.1, 1.0 and 10 s-1 were considered. It was found that all obtained stress-strain responses of manganese aluminum bronze showed a single peak stress that afterwards approached a steady flow stress. Additionally, constitutive equations based on the Arrhenius model were applied for describing the determined flow stresses, in which Zener-Hollomon parameter in a hyperbolic-sine function was taken into account. By the flow stress modeling, the activation energy of about 194 kJ/mol was calculated for the examined manganese aluminum bronze.
Deflection Simulation of Ionic Polymer Metal Composites (IPMC) Actuators for Bionic Knee Joints
Authors: Farid Muhammad , Gang Zhao , Khuong Tran Linh , Rehman Naveed Ur , Adnan Saifullah
Published: April 2015

Ionic Polymer Composite Material (IPMC) is a new type of smart material which has the capability of activation under the application of a small voltage. It is flexible; light weighed, produces high force and can be activated in any two opposite directions. These benefits have inspired the scientists and researchers to explore its availability for real-world applications in various fields. In this paper, the application of IPMC has been considered for the provision of required force to the movement of a grasshopper knee joint for the upward or stretching movement by the knee. In other words, it has been proposed to act as an artificial muscle for the mentioned job. Furthermore, simulation is carried out for two separate conditions of the weight ratios of the weight of the leg and that of the IPMC strip and simulation is carried out to clarify the relation between the force and deflection. The simulation is based on mathematical model that has been previously developed. Analysis of the simulation results of the two conditions indicated that more force is required to move a heavier leg by a certain amount of angle as compared to the force requirement for moving a lighter leg. This paper represents the simulation results for the upward movement of the link; however the same model and its simulation can be applied to that of the reverse direction because of the unanimity of the material properties and specifications.
Effects of Design Parameters for Clay Brick Kiln Using Computational Fluid Dynamics and Experimental Design
Authors: Ratanathavorn W. , Charoenjai S. , Janbuala Sutas , Chalermsinsuwan B. , Poochinda K.
Published: April 2015

One of the most critical steps in brick making is firing, performed to harden the bricks. In a typical non-industrial setting, many pieces of extruded clays are stacked into a box-shaped kiln with equally-spaced rectangular vertical holes and another set of equally-spaced horizontal holes at the bottom across two sides. Roman roof tiles are used to cover the vertical sides, while leaving the horizontal holes opened, to complete the kiln assembly. Rice husk is filled in the holes of the kiln and is used as the fuel for firing. However, approximately 10% of the bricks, stacked conventionally, are always not appropriately fired. Therefore, this research aimed at simplifying model and redesigning the clay brick kiln using three-dimensional computational fluid dynamics (CFD). The studied parameters for 23 factorial designs were as follows: kiln height (200 – 225 cm), horizontal holes width (7.5 – 15 cm) and height (45 – 60 cm). The total volume of brick stack, averaged steady-state temperature and time to reach a steady-state temperature were selected as the response parameters. The analysis of variance (ANOVA) of 23 factorial design showed that the width and height of holes affected the time to reach steady-state but the averaged steady-state temperature and the total volume of brick stack were dependent on all 3 parameters. Then, a kiln was constructed according to the model with the maximum number of bricks and only 4% of the bricks were not appropriately fired.
Structural, Elastic and Optical Properties of Ag-Doped Rutile TiO2
Authors: Mahmood Waqas
Published: April 2015

The structural, elastic and optical properties of Ag-doped rutile TiO2 are studied using the first principles calculations method. Four different functionals are employed using the ultrasoft pseudopotentials (USPs) on a supercell of size 2a × 2b × 1c. The band gaps of un-doped TiO2 obtained using PBE, RPBE, PW91 and LDA-CA-PZ are 1.861, 1.873, 1.857 and 1.854 eVs respectively. However, after Ag substitution in the supercell, the band gaps are reduced for all of the functionals. After substitution, in the region near to the Fermi level, some new electronic states are observed. The calculated elastic constants show that the structure is mechanically stable. The obtained values of the B, G and elastic constants of un-doped TiO2 are consistent with prior published experimental findings. For Ag-doped supercell, implementing PW91, B and G are 119 and 62 GPa. For the same size of supercell, using LDA-CA-PZ, B and G are 152 and 70 GPa. Besides, the results of the optical properties show that the major absorption peaks for all of the functionals locate away from the visible region. This shows poor absorption of visible light and weak photocatalytic activity of rutile TiO2.
A Novel Preparation of Carbon Foams Derived from Albumen
Authors: Zhang Bo Ya , He Xing , Xu Kai Yu , Bu Tian Ling
Published: April 2015

Most of the carbon foams’ preparation is conducted under either high temperature or high pressure which consumes much energy. Aimed at this problem, we proposed a novel preparation technology which utilized the albumen as the foaming agent under normal temperature and pressure. The carbon foams had a bulk density of between 0.38 and 0.44 g/cm3. Analysis of scanning electron micrographs indicated that the cells had spherical cavity, small transom, and ligament which connected spherical cavity and provided high mechanical properties. The compressive strengths ranged from 0.4 to 2.1MPa and the thermal conductivity stayed still when the content of the meso-carbon micro-beads (MCMB) varied between 0 and 10%. It is one of our method’s features that the content of MCMB has litter effect on the thermal conductivity of the carbon foams.
Thermal Property Evaluation of Chilled Aluminum-Alumina MMC
Authors: Suresh B.C. , Arun S.B.
Published: April 2015

Now a day’s composite materials are taking very important role in industrial growth. Composite materials are widely used in Automobiles, aerospace, submarine and also in other major fields, due to their special characteristics like light weight, high strength, stiffness, corrosion resistance. The determination of Coefficient of Thermal Expansion (CTE) of MMCs is important to aid its usage in high temperature environment as in the case of automobile combustion chamber. In these applications the stability of the composites over a long period of operation is a critical design considerationPresent work deals with the thermal property evaluation of the Al alloy / alumina metal matrix composite developed using the Stir Casting with chilling route technique. LM 26 Al alloy is being selected as the matrix material as it is a potential alloy for automotive piston applications. Al alloy / alumina MMCs was cast under end chilling technique by dispersing the reinforcement from 6 to 12 wt% the steps of 3% to study the variation in its thermal properties. At the same time chill material is also changed (Copper and MS) for different composition of MMCs cast to study the thermal behavior variations. After casting the required MMC, test specimens were prepared as per the standards to conduct thermal conductivity (K) tests and coefficient of thermal expansion (CTE) tests. Above tests were repeated for different composites containing different weight % of dispersed cast using different chills.
Deformation Behavior of Cu-8wt%Ag Alloy during Equal Channel Angular Pressing
Authors: Shen Yue , Ren Chuan Ting , Zhang Guo Quan , Xie Ming , Wen Ming , Cheng Qi Bing , Guan Wei Ming
Published: April 2015

The shear deformation behavior of the course-grained Cu-8wt%Ag alloy processed by one pass of equal channel angular pressing (ECAP) was revealed through the metallurgical microscope and the scanning electron microscope. Through the macro-level and micro-level synthesis analysis, it is confirmed that there are two shear deformation during the ECAP processing: the one along the intersection plane (IP) and the other along the vertical plane to the IP. And it is estimated that theoretical ranges of two shear angles are-32°<θ1<0° and 43°<θ2<58° respectively. Finally, it is also proved that the evolution of the shear bands is affected by the parallel and vertical shear to the IP of the ECAP die, and that, besides the shear along the IP, the shear along the vertical plane to the IP also plays an important role during the plastic deformation.
Wind Energy Potential in Kuching Areas of Sarawak for Small-Scale Power Application
Authors: Lawan S.M. , Abidin W.A.W.Z. , Chai W.Y. , Baharun Azhaili , Masri Thelaha
Published: April 2015

Energy is a catalyst for national development; most of the countries depend on hydrocarbon fuels for power generation. The traditional sources of energy are exorbitant and finite. In addition, they emit excessive carbon dioxide and other gases into the lower layer of the atmosphere which influence the increase occurrence of global warming in the world. Recently, renewable energy’s are gaining more attraction and attention in many parts of the globe, due to non-polluting characteristics. Among the renewable, wind power has emerged as safest and cleanest resource that will satisfy the need of energy in a cost effective way. Wind energy system can suit the energy need for grid and stand alone mode. This paper investigates the potential of wind energy in Kuching for small-scale application. The study employed three years wind speed data spanning from 2010-2012 observed at the Kuching meteorological station. Details of the analysis and potential of using wind energy systems are presented. Additionally, the output performances of two wind turbines are examined on the basis of the computed Weibull distribution.
Modelling and Simulation of Trigeneration Systems Integrated with Gas Engines
Authors: Ekwonu M.C. , Perry Simon , Oyedoh E.A.
Published: April 2015

In this paper, the integration of Gas Engines with the Rankine cycle and Organic Rankine cycle for use as a combined cooling, heating and power (CCHP) system was investigated. The gas engine model, Organic Rankine Cycle model, Rankine Cycle model and single effect absorption chiller model were developed in Aspen HYSYS V7.3®. The system performance of the combination of the Rankine Cycle and Organic Rankine Cycle was investigated with two different configurations. The series and parallel combination of Rankine and Organic Rankine Cycle integration with the gas engine showed an increase of 7% and 15% respectively both in the overall system efficiency and power generated. The trigeneration system provided a cooling duty of 18.6 kW, a heating duty of 704 kW to a district heating system with 3.9 MW of power generated and an overall trigeneration efficiency of 70%. The system also gave a 9% increase in the power generated when compared to the gas engine without waste heat recovery whilst bottoming with Rankine cycle, Organic Rankine cycle and Absorption refrigeration system.Keywords: Modelling, Trigeneration, Gas Engines, Waste Heat Recovery, Rankine Cycle, Organic Rankine Cycle.
The Use of Natural Zeolite as an Additive in Warm Mix Asphalt with Polymer Modified Asphalt Binder
Authors: Handayani Ani Tjitra , Setiaji Bagus Hario , Prabandiyani Sri
Published: April 2015

Asphalt Concrete mixture of polymer modification are used to reduce the damage early and increasing the durability of pavement to various damage such as permanent deformation, cracking due to temperature changes, fatigue During this process the polymer asphalt mixing using Hot Mix Asphalt / HMA. In accordance with the name and nature of hot mix asphalt, require high enough heating temperature on the Asphalt Mixing Plant (AMP), and also requires a high temperature compaction. As a result, it takes quite a lot of fuel so produced a large exhaust emissions. Emissions generated during the mixing process and compaction of HMA is a challenge for the environment. Some countries have developed a method of asphalt mixture to overcome this by using Warm Mix Asphalt technology. Warm Mix Asphalt is the technology of mixing and compaction temperatures of asphalt mixtures using mixing and compaction temperatures lower than Hot Mix Asphalt. Decreasing the mixing and compaction temperatures by adding additives to the asphalt mixture. Types of additives that have been widely used and developed for Warm Mix Asphalt them is the use of synthetic zeolites with various trademarks such as Aspha-min (R), Sasobit(R) dan Advera(R). In this paper the synthetic zeolite will be replaced by natural zeolite as an additive to be mixed with a mixture of Polymer Modified Asphalt Concrete. This study uses laboratory testing, using aggregate materials from Subang, West Java, Asphalt Elastomer Polymers, natural zeolite mineral mordenite sourced from Bayat, Central Java, Indonesia. Tests using a mixture Marshall Test. Marshall test results stated that the levels of natural zeolite 1% can reduce the temperature of mixing and compaction temperatures on Polymer Modified Concrete Asphalt mix 30°C, lower than the temperature of the mixture of Polymer Modified Asphalt Concrete without zeolite. Keywords: additive, Natural Zeolites, Warm Mixed Asphalt, Polymer Modified Asphalt Concrete
Integrating Bayesian Model Averaging for Uncertainty Reduction in Permeability Modeling
Authors: Al-Mudhafar Watheq
Published: April 2015

This paper describes a new procedure of model selection in linear regression analysis to efficiently model and predict the formation permeability in non-cored intervals. The simplest way of model selection in regression model is to adopt stepwise elimination that depends on the probability of null hypotheses. However, the new method is the Bayesian Model Averaging (BMA) that selects the most appropriate model for a given outcome variable based on Bayes factors.

Model selection process in BMA considers model's posterior probability and Bayesian Information Criterion (BIC). BMA produces a posterior distribution of the outcome factor that represents the weighted average of the posterior distributions of that factor for each likely model. Only five models are selected that their posterior probabilities sum to be equal to one. The best model selection has the maximum posterior probability and minimum Bayesian Information Criterion; nevertheless, the model subset selection is determined when the probability of a non-zero predictor's coefficient is more than 90 % for the best sampled model. That means this predictor has an effect on the outcome and should be included in the regression model. All these variables are shown in the computed Occam's window.

The results showed that MBA algorithm has to achieve perfect t-test and analysis of variance especially regarding the rejection of null hypotheses for all the subselected independent variables. In addition, the reduced BMA model has been evaluated through Mean Square Prediction Error (MSPE) and residual analysis that clearly shows uncertainty reduction in permeability estimation. Therefore, the predicted permeability values for the entire formation depth are much more compatible with the measured data than the linear regression model.
An Analysis of the Effect of Surfactant Flood on Residual Oil under Composition-Dependent Multi-Contact Water-Oil Miscibility in a North Sea Reservoir
Authors: Temizel Cenk , Purwar Suryansh , Urrutia Karelis , Abdullayev Azer , Agarwal Amit
Published: April 2015

Surfactant flooding has become a more common method in recent decades in which the phase behavior inside the reservoir can be manipulated by the injection of surfactants, leading to favorable conditions to mobilize trapped oil. Carefully designed surfactants that are injected into the crude oil can generate microemulsions at the interface between crude oil and water, thereby reducing the interfacial tension to very low levels, which ultimately mobilizes the residual oil. However, the adsorption of surfactant to the rock during the injection and chromatographic separation of the surfactant in the reservoir are critical phenomena in which the surfactants must be resistant to reservoir conditions, including high pressures and temperatures. The application of surfactant methods is usually constrained by the cost of the chemicals and is adversely affected by adsorption and loss into the rock, making it crucial to understand the significance of those factors that affect the performance of this enhanced oil-recovery method so that more robust decisions can be made. This study aims to outline the lessons learned regarding the impact that these factors had on a North Sea reservoir.

In this study, a reservoir simulation model is harnessed in which the injection of cold water into the initially hot reservoir results in a reverse temperature gradient is simulated using a commercial full-physics reservoir simulator. A surfactant slug is followed by several years of water injection, where the reservoir contains a light oil trapped between a gas cap and an aquifer.

Surfactant effects on residual-oil detrapping and wettability are modeled by interpolating between relative permeability sets according to a capillary number, which depends on temperature and surfactant concentration, where composition-dependent K-values describe multiple-contact water-oil miscibility according to the concentration of water-based surfactant in which the adsorption of surfactant affects its availability and propagation.

Using a real reservoir model coupled with a robust optimization tool to provide useful insights beyond the limitations of the theoretical results, this study takes an extra step beyond experimental data and simulation studies that are carried out with synthetic models. The influence of each decision and uncertainty parameter important in reservoir management decisions is outlined with the optimization results under different scenarios on the performance of surfactant flood, thereby illustrating the phenomenon with a real reservoir model that will shed light onto similar cases.
Delta House Project Overview
Authors: Fowler R. L. , Zimmermann E. C. , Leimkuhler J. M. , Mullett C. , Cooley B. , Paternostro B. , Boelte J.
Published: April 2015

This paper provides an overview of the Delta House Project. The Delta House Floating Production System (FPS) in located in the Mississippi Canyon protraction area of the Gulf of Mexico in block 254 and will initially process production from three "anchor" fields varying from six to fourteen miles from the FPS. The FPS uses the Exmar Offshore designed OPTI-1100® semisubmersible design which has a nameplate capacity of 80 MBOPD and 200 MMCFD with peaking capacity of 100 MBOPD and 240 MMCFD. The Delta House anchor fields are primarily oil bearing Miocene sands in a channel levee turbidite depositional environment. Seven wells have been drilled to date in the initial anchor fields. Each anchor field will be developed with (i.e. wet trees) flowing to subsea manifolds and subsequently to the FPS via two infield flowloops using steel catenary risers. The project includes a 12" oil export line and 16" gas export line using steel catenary risers.

There are several unusual aspects of the Delta House project. The project went from first discovery to first production in about three years which is significantly less than other projects involving a new FPS. Engineering for the FPS and bidding of construction yards began prior to the first Delta House discovery. The Delta House FPS and export lines are owned by special purpose entities funded primarily by private equity.

This paper will provide a history of the project and will highlight the reasons for some of the key decisions that were made throughout the development.
Vertical Cable Seismic (VCS) Survey for SMS exploration in Izena Cauldron, Okinawa-Trough
Authors: Asakawa Eiichi , Murakami Fumitoshi , Tsukahara Hitoshi , Mizohata Shigeharu , Tara Kenji
Published: April 2015

The Vertical Cable Seismic (VCS) survey is one of the reflection seismic methods. It uses hydrophone arrays vertically moored from the seafloor to record acoustic waves generated by seismic sources. Because the VCS is an efficient high-resolution 3D seismic survey method for a spatially bounded area, we proposed it for the SMS survey tool development program started by Japanese government. In 2010, we manufactured the autonomous VCS data acquisition systems. Through several experimental surveys, our VCS is successfully completed. In 2011 and 2013, we carried out the two VCS surveys using GI gun and high-voltage sparker respectively in the Izena Cauldron, Okinawa Trough, which is one of the most promising SMS areas around Japan. Because seismic survey is not proven to be effective for SMS exploration, no seismic surveys have been conducted there so far. However, our VCS results are consistent with geological information from the cores of the nearby borehole and give useful information to SMS exploration..

In 2014, the Japanese government started the Cross-ministerial Strategic Innovation Promotion Program (SIP), which includes "Next-generation technology for ocean resource exploration". Our Vertical Cable Seismic (VCS) survey technique is accepted by this program, especially for the exploration of Seafloor Massive Sulfides (SMS) and we continue its development.
Low Frequency Seismic Acquisition Innovations Approaching One Hertz
Authors: Meier Mark , Lewallen Kyle , Otero Jose , Heiney Steve , Murray Tom
Published: April 2015

Expanding the low frequency seismic band promises to improve subsurface imaging and inversion and reduce risks in exploration and production of hydrocarbons. Modern seismic acquisition technologies measure several octaves of earth response. New acquisition technologies can provide several more octaves of low frequencies.

The industry has made substantial effort towards modifying existing acquisition technologies to capture additional low frequencies without compromising the higher frequencies. This approach relies on existing acquisition technology concepts. In our work, we set out to identify those specific traits found in existing acquisition technologies that are obstacles to step-change improvements in low frequency bandwidth. We then sought to devise new technology concepts that dispense with those traits. For example; the low frequency ghost notch is a major obstacle for marine seismic sources, land and marine sources suffer orders-of-magnitude losses in force output at low frequencies, and measurements from motion sensors in multicomponent streamers are problematic at low frequencies due to streamer dynamics. We have devised alternative technology concepts for seismic sources and multicomponent streamers that address these challenges; namely, the marine dipole seismic source, the counter-rotating eccentric mass actuator, and the pressure gradient transducer.

We are presently in research and development stages of these new technologies and are obtaining encouraging results. Our theoretical work predicts technical feasibility, and our experimental studies have confirmed tested aspects of the theory. We conclude these technologies have potential to extend the low frequency seismic band at least two octaves beyond modern capabilities. More experimental work remains to be completed, but based on the evidence gathered so far, we are persuaded to begin consideration of the next stages in development and commercialization.
Reassessment of Subsea processing Technology to Maximize Recovery on Offshore Marginal Field Developments
Authors: Ohanyere I. J. , Abili N
Published: April 2015

Objective/Scope

International and National oil companies have in their portfolios deep offshore marginal fields. Development of these fields is usually constrained by the CAPEX, OPEX, flow assurance and safety issues, which increases with maturity of the field. Subsea processing technology (SPT) is not only pivotal for unlocking such fields, but offers a novel approach that meets the challenges of developing offshore marginal fields. The present paper explores conceptual development from some of the most innovative solutions and performance analysis of the optimal SPT with field case studies demonstrated.

Methods, Procedures, Process

The paper provides a reassessment of the different SPTs available in the market as well as the limitations of such technologies. Conceptual development is carried out using a 3-step approach involving the Quality function deployment (QFD) and its tools, the Voice of customer (VOC) and Quality Matrix or House of Quality (HOQ) that analyzes and compares the capabilities of various SPTs to overcome the techno-economic challenges of marginal fields. Revalidation of results from the QFD process is done using Analytical Hierarchal process (AHP) and its pair wise comparison process, leading to the optimal innovative SPT for marginal field development. Field case analysis of this novel solution is applied to fields in the North Sea and Gulf of Guinea over an eight years period.

Results, Observations, and Conclusions

The present paper validates the effectiveness of SPT in tackling marginal field techno-economic challenges such as large CAPEX and OPEX, slugging, low recovery rate, remoteness of location amongst others issues. Its application in one of the fields led to increased projected revenue of up to $450,000,000 in recovery, as well as significant reduction in maintenance and work over costs. The analysis shows that SPT such as the deployment of Multiphase Pumps can be a game changer if effectively applied in marginal field development.

Novel/Additive Information

The paper explores the novel application of QFD and AHP to develop offshore marginal fields. These tools have been used effectively in so many fortune 500 companies, where they have led to a significant reduction in cost as well as reduction in project implementation time. Proper application of the processes described in the present paper can serve as a better alternative over the traditional field conceptual development, to maximize recovery in offshore marginal fields.
Riserless Light Well Intervention Operations in Harsh Environment - A Case Study from West of Shetland
Authors: Løver Terje A. , Bjerkvik Oddbjørn
Published: April 2015

The area West of Shetland (WoS) between the UK and Faroe Islands, also known as the Atlantic Frontier, is characterized by a harsh environment with strong currents, presenting significant challenges for offshore operations. Our experience in this area began for the first time in 2009, performing Riserless Light Well Intervention (RLWI) operations. This type of well intervention had never been performed in this area and the challenge showed to be far bigger than first anticipated.

This is the seventh season with RLWI operations West of Shetland, an environment which is known to be very challenging due to extreme ocean currents. The first season there were significant struggles with the difficult environmental conditions. Strong currents caused damages to both RLWI equipment and vessel, forcing the operation to be stopped. To be able to complete the operations a quick adaption to this demanding environment was needed. The organization managed to turn around quickly and do the needed modification to respond to the challenging environment, making it possible to complete the operations in this harsh environment. After a steep learning curve and 6 years operational experience in this area, the operations are now completed ahead of schedule.

This paper will discuss the challenges experienced performing RLWI operations West of Shetland. Damages to equipment caused by the harsh environment and the “battle” to overcome these challenges will be discussed.
Ultra-High Conductivity Umbilicals: Polymer Nanotube Umbilicals
Authors: Dyke C. , Ecklund M. , Horton H.
Published: April 2015

This document describes the work performed and scheduled to satisfy the terms of the Research Partnership to Secure Energy for America (RPSEA) contract number 10121-4302-01. NanoRidge, Inc., located in Houston, Texas, is the prime contractor and has subcontracted Rice University and DUCO, Inc. to participate in this endeavor. Representatives from Shell, Weatherford, Total, and Technip Umbilicals, the project's cost share partners, comprise the Steering Committee and Working Project Group. The ultimate goal and culmination of work is to use a carbon nanotube wire as the conductor in a prototype power cable umbilical. Once accomplished, the technology, starting at a technology readiness level (TRL) of 1, would have a TRL of 5 to 6. The project was instituted to replace copper wire with a carbon-based conductor. The difficulties with copper include a) corrosion, particularly at wire terminations, and b) strength, in some applications the weight of copper exceeds its tenacity. The conductor formed in this effort shall overcome these difficulties. The technical steps to achieve this goal are the continuous production of CNT wire with in-line post processing steps to form the bare conductor. The resistivity of the carbon nanotube wire shall be equal to copper at one sixth the weight. Once the conductivity is achieved, the wire shall be jacketed with polymer. This material we have termed the polymer nanotube umbilical (PNU) cable. Since the wire is nonmetal, we anticipate minimal saltwater corrosion. Also, the CNT conductor shall have greater tensile strength than copper. The following is described in this paper: 1) our technical approach and progress, 2) specialty equipment, and 3) Phase I and II results.
Field Applications for Advanced Robotics
Authors: Nayar Hari D.
Published: April 2015

Applications of advanced robotics systems have grown over the past couple of decades in a wide range of industries. These include deployments in the space, military, manufacturing, mining, agriculture, emergency-response, oil and gas, transportation and many other sectors. Innovations in materials, sensors, actuators, mechanical design, computing hardware, software architectures, modeling and simulation, control algorithms, motion planning, machine perception, artificial intelligence and machine learning have all contributed to the highly capable and reliable robotics systems available today. At NASA's Jet Propulsion Laboratory (JPL), robots that integrate technologies from all these disciplines are being developed for a variety of space and terrestrial applications. This paper will give an overview of some of the state-of-the-art technologies being developed at JPL and describe potential applications for them in the oil and gas industry. Robotics skills and expertise at JPL are broadly categorized by discipline into the general areas of mechanical & electrical hardware development, modeling & simulation, mobility systems, manipulation & sampling systems, computer vision & perception, estimation & control, and operations. Through the life cycle of a robotics project, these skills are drawn on, usually with hardware, embedded systems and modeling and simulation development emphasized in the early stages and transitioning to advanced control, behavior and intelligence development at the later stages. Integration of these capabilities into robotics systems has resulted in a number of cutting-edge applications in planetary exploration, in-space servicing, surgery, ground, marine and aerial vehicles, and search & rescue. Areas in the offshore industry where these technologies could be applied include surveillance, inspection and maintenance of offshore surface and underwater facilities, automation of drilling, and production processes, safety and security monitoring and spill monitoring and cleanup. The benefits to be gained in developing robotics systems for oil and gas applications include reduced exposure of human operators to hazardous conditions, improved precision & reliability, and reduced cost. Current robotics technology is sufficiently mature for near-term applications in surveillance, inspection and maintenance operations for facilities and sub-sea systems. More sophisticated systems could be used in the future for challenging applications like autonomous well intervention, pipe inspection, and deepwater maintenance and repair. Potential oil and gas applications for surveillance and inspection of facilities, subsea infrastructure and pipelines are illustrated.