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2015

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Implications Of Electric Vehicles On Gasoline Tax Revenues, Florida Solar Energy Center, Kevin Schleith Dec 2015

Implications Of Electric Vehicles On Gasoline Tax Revenues, Florida Solar Energy Center, Kevin Schleith

FSEC Energy Research Center®

This report summarizes the results of research conducted to determine if current and near future EV sales will have an impact on gasoline (gas) tax revenues as part of the Federal Highway Trust Fund (HTF). Gasoline taxes account for $31.1 billion or about 87% of the HTF. The project results were accomplished through a review of existing industry and government reports that detail fuel tax revenues and through analysis of EV sales from 2010 to 2015.


Numerical-Analytical Assessment On Solar Chimney Power Plant, Nima Fathi, Seyed Sobhan Aleyasin, Peter Vorobieff Dec 2015

Numerical-Analytical Assessment On Solar Chimney Power Plant, Nima Fathi, Seyed Sobhan Aleyasin, Peter Vorobieff

Nima Fathi

This study considers an appropriate expression to estimate the output power of solar chimney power plant systems (SCPPS). Recently several mathematical models of a solar chimney power plant were derived, studied for a variety of boundary conditions, and compared against CFD calculations. An important concern for modeling SCPPS is about the accuracy of the derived pressure drop and output power equation. To elucidate the matter, axisymmetric CFD analysis was performed to model the solar chimney power plant and calculate the output power for different available solar irradiation. Both analytical and numerical results were compared against the available experimental data from …


Analysis Of Capillary Flow In Interior Corners : Perturbed Power Law Similarity Solutions, Joshua Thomas Mccraney Dec 2015

Analysis Of Capillary Flow In Interior Corners : Perturbed Power Law Similarity Solutions, Joshua Thomas Mccraney

Dissertations and Theses

The design of fluid management systems requires accurate models for fluid transport. In the low gravity environment of space, gravity no longer dominates fluid displacement; instead capillary forces often govern flow. This thesis considers the redistribution of fluid along an interior corner. Following a rapid reduction of gravity, fluid advances along the corner measured by the column length z = L(t), which is governed by a nonlinear partial differential equation with dynamical boundary conditions. Three flow types are examined: capillary rise, spreading drop, and tapered corner. The spreading drop regime is shown to exhibit column length growth L ~ …


Direct Numerical Simulation Of Cylindrical Particle-Laden Gravity Currents, ‪Nadim Zgheib, Thomas Bonometti, S. Balachandar Dec 2015

Direct Numerical Simulation Of Cylindrical Particle-Laden Gravity Currents, ‪Nadim Zgheib, Thomas Bonometti, S. Balachandar

Mechanical Engineering Faculty Publications and Presentations

We present results from direct numerical simulations (DNS) of cylindrical particle-laden gravity currents. We consider the case of a full depth release with monodisperse particles at a dilute concentration where particle–particle interactions may be neglected. The disperse phase is treated as a continuum and a two-fluid formulation is adopted. We present results from two simulations at Reynolds numbers of 3450 and 10,000. Our results are in good agreement with previously reported experiments and theoretical models. At early times in the simulations, we observe a set of rolled up vortices that advance at varying speeds. These Kelvin–Helmholtz (K–H) vortex tubes are …


Mechanical Engineering News, Georgia Southern University Dec 2015

Mechanical Engineering News, Georgia Southern University

Mechanical Engineering News (2013-2023)

  • Georgia Southern Research Focus Prompts R2 Carnegie Designation


Mapping Chemical Selection Pathways For Designing Multicomponent Alloys: An Informatics Framework For Materials Design, Srinkant Srinivasan, Scott R. Broderick, Ruifeng Zhang, Amrita Mishra, Susan B. Sinnott, Surendra Saxena, James M. Lebeau, Krishna Rajan Dec 2015

Mapping Chemical Selection Pathways For Designing Multicomponent Alloys: An Informatics Framework For Materials Design, Srinkant Srinivasan, Scott R. Broderick, Ruifeng Zhang, Amrita Mishra, Susan B. Sinnott, Surendra Saxena, James M. Lebeau, Krishna Rajan

Department of Mechanical and Materials Engineering

A data driven methodology is developed for tracking the collective influence of the multiple attributes of alloying elements on both thermodynamic and mechanical properties of metal alloys. Cobalt-based superalloys are used as a template to demonstrate the approach. By mapping the high dimensional nature of the systematics of elemental data embedded in the periodic table into the form of a network graph, one can guide targeted first principles calculations that identify the influence of specific elements on phase stability, crystal structure and elastic properties. This provides a fundamentally new means to rapidly identify new stable alloy chemistries with enhanced high …


Turning An Organic Semiconductor Into A Low-Resistance Material By Ion Implantation, Beatrice Fraboni, Alessandra Scidà, Piero Cosseddu, Yongqiang Wang, Michael Nastasi, Silvia Milita, Annalisa Bonfiglio Dec 2015

Turning An Organic Semiconductor Into A Low-Resistance Material By Ion Implantation, Beatrice Fraboni, Alessandra Scidà, Piero Cosseddu, Yongqiang Wang, Michael Nastasi, Silvia Milita, Annalisa Bonfiglio

Nebraska Center for Energy Sciences Research: Publications

We report on the effects of low energy ion implantation on thin films of pentacene, carried out to investigate the efficacy of this process in the fabrication of organic electronic devices. Two different ions, Ne and N, have been implanted and compared, to assess the effects of different reactivity within the hydrocarbon matrix. Strong modification of the electrical conductivity, stable in time, is observed following ion implantation. This effect is significantly larger for N implants (up to six orders of magnitude), which are shown to introduce stable charged species within the hydrocarbon matrix, not only damage as is the case …


Electromechanics Of An Ocean Current Turbine, Vasileios Tzelepis Dec 2015

Electromechanics Of An Ocean Current Turbine, Vasileios Tzelepis

University of New Orleans Theses and Dissertations

The development of a numeric simulation for predicting the performance of an Ocean Current Energy Conversion System is presented in this thesis along with a control system development using a PID controller for the achievement of specified rotational velocity set-points. In the beginning, this numeric model is implemented in MATLAB/Simulink® and it is used to predict the performance of a three phase squirrel single-cage type induction motor/generator in two different cases. The first case is a small 3 meter rotor diameter, 20 kW ocean current turbine with fixed pitch blades, and the second case a 20 …


Developing And Testing An Anguilliform Robot Swimming With Theoretically High Hydrodynamic Efficiency, John B. Potts Iii Dec 2015

Developing And Testing An Anguilliform Robot Swimming With Theoretically High Hydrodynamic Efficiency, John B. Potts Iii

University of New Orleans Theses and Dissertations

An anguilliform swimming robot replicating an idealized motion is a complex marine vehicle necessitating both a theoretical and experimental analysis to completely understand its propulsion characteristics. The ideal anguilliform motion within is theorized to produce ``wakeless'' swimming (Vorus, 2011), a reactive swimming technique that produces thrust by accelerations of the added mass in the vicinity of the body. The net circulation for the unsteady motion is theorized to be eliminated.

The robot was designed to replicate the desired, theoretical motion by applying control theory methods. Independent joint control was used due to hardware limitations. The fluid velocity vectors in the …


Design, Manufacturing And Control Of An Advanced High-Precision Robotic System For Microsurgery, Arezoo Ebrahimi Dec 2015

Design, Manufacturing And Control Of An Advanced High-Precision Robotic System For Microsurgery, Arezoo Ebrahimi

Electronic Theses and Dissertations

Microsurgeries like ophthalmic surgery confront many challenges like limited workspace and hand motion, steady hand movements, manipulating delicate thin tissues, and holding the instrument in place for a long time. New developments in robotically-assisted surgery can highly benefits this field and facilitate those complicated surgeries. Robotic eye surgery can save time, reduce surgical complications and inspire more delicate surgical procedures that cannot be done currently by surgeon’s hands. In this thesis work, the requirements for ophthalmic surgeries were studied and based on that a robotic system with 6 DOF is proposed and designed. This robotic

system is capable of handling …


A General-Purpose Multiphase/Multispecies Model To Predict The Spread, Percutaneous Hazard, And Contact Dynamics For Nonporous And Porous Substrates And Membranes, Homayun K. Navaz, Ali R. Zand, Amir Gat, Theresa S. Atkinson Dec 2015

A General-Purpose Multiphase/Multispecies Model To Predict The Spread, Percutaneous Hazard, And Contact Dynamics For Nonporous And Porous Substrates And Membranes, Homayun K. Navaz, Ali R. Zand, Amir Gat, Theresa S. Atkinson

Mechanical Engineering Publications

A computational model to solve the coupled transport equations with chemical reaction and phase change for a liquid sessile droplet or the contact and spread of a sessile droplet between two approaching porous or non-porous surfaces, is developed. The model is general therefore it can be applied to toxic chemicals (contact hazard), drug delivery through porous organs and membranes, combustion processes within porous material, and liquid movements in the ground. The equation of motion and the spread of the incompressible liquid available on the primary surface for transfer into the contacting surface while reacting with other chemicals (or water) and/or …


Electronic Musical Instrument To Generate Musical Tones To Imitate A Stringed Instrument, Mizuki Nakagawa, Ikuo Tanaka, Shun Takai Dec 2015

Electronic Musical Instrument To Generate Musical Tones To Imitate A Stringed Instrument, Mizuki Nakagawa, Ikuo Tanaka, Shun Takai

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Provided are an electronic musical instrument, computer storage device, and method for generating tone. A sound source in an electronic musical instrument generates a first tone at a first pitch in response to a first tone generation instruction received by an input device of the electronic musical instrument. A second tone generation instruction is received to generate a second tone at a second pitch while generating the first tone at the sound source. A determination is made of a pitch difference of the first and the second pitches. The sound source is controlled to generate the second tone and to …


Towards The Development Of A Wearable Tremor Suppression Glove, Yue Zhou Dec 2015

Towards The Development Of A Wearable Tremor Suppression Glove, Yue Zhou

Electronic Thesis and Dissertation Repository

Patients diagnosed with Parkinson’s disease (PD) often associate with tremor. Among other symptoms of PD, tremor is the most aggressive symptom and it is difficult to control with traditional treatments. This thesis presents the assessment of Parkinsonian hand tremor in both the time domain and the frequency domain, the performance of a tremor estimator using different tremor models, and the development of a novel mechatronic transmission system for a wearable tremor suppression device. This transmission system functions as a mechatronic splitter that allows a single power source to support multiple independent applications. Unique features of this transmission system include low …


Guided Wave Based Integrated Structural Health Monitoring And Nondestructive Evaluation, Zhenhua Tian Dec 2015

Guided Wave Based Integrated Structural Health Monitoring And Nondestructive Evaluation, Zhenhua Tian

Theses and Dissertations

Damage detection and health monitoring are critical for ensuring the structural safety in various fields, such as aerospace, civil and nuclear engineering. Structural health monitoring (SHM) performs online nondestructive evaluation (NDE) and can predict the structural remaining life through appropriate diagnosis and prognosis technologies. Among various SHM/NDE technologies, guided ultrasonic waves have shown great potential for fast and large area SHM/NDE, due to their sensitivity to small defects and capability to propagate long distances. Recent advances in guided wave based SHM/NDE technologies have demonstrated the feasibility of detecting damage in simple structures such as metallic plates and pipes. However, there …


A Multiphysics Modeling Of Solid Oxide Metal-Air Redox Battery, Md Ahsan Uddin Dec 2015

A Multiphysics Modeling Of Solid Oxide Metal-Air Redox Battery, Md Ahsan Uddin

Theses and Dissertations

Cost-effective and large scale energy storage is essential for the growth of the future’s ‘‘green energy’’ infrastructure. Among the energy storage technologies currently being used, rechargeable batteries represent a class of advanced electrical energy storage (EES) mechanisms that can be valuable for the future renewable integration and smart grid. Rechargeable batteries have innumerous advantages over the conventional pumped hydro and compressed-air energy storage system. Now days, There are various types of rechargeable batteries available to work as an energy storage device in a smart grid but it still needs many breakthroughs to become commercially viable for stationary energy storage. First …


Wavelet Analysis Of Periodic Error In Heterodyne Interferometry, Chao Lu Dec 2015

Wavelet Analysis Of Periodic Error In Heterodyne Interferometry, Chao Lu

Theses and Dissertations

Heterodyne displacement measuring interferometry provides important metrology for applications requiring high resolution and accuracy. Heterodyne Michelson interferometers use a two-frequency laser source and separate the two optical frequencies into one fixed length and one variable length path via polarization. Ideally these two beams are linearly polarized and orthogonal so that only one frequency is directed toward each path. An interference signal is obtained by recombining the light from the two paths; this results in a measurement signal at the heterodyne (split) frequency of the laser source. This measurement signal is compared to the optical reference signal. Motion in the measurement …


Bio-Inspired Design Of Mechanical Band Pass Sensor With The Ability To Scavenge Energy, Md Riaz Uddin Ahmed Dec 2015

Bio-Inspired Design Of Mechanical Band Pass Sensor With The Ability To Scavenge Energy, Md Riaz Uddin Ahmed

Theses and Dissertations

Primary objective of this work is to introduce the multi-scale computational model for the bio-inspired acousto-ultrasonic band pass sensor that are capable of mechanically sense and/or filter wide range user defined frequencies. Selecting a particular and/or a distinct band of frequencies is essential for many applications in science engineering and technologies. For example design of sensors in chemical, biomedical and biological applications; device application for acoustic modulation by breaking the acoustic reciprocity and the sensors used in precision manufacturing applications requires sensing and/or filtering of wide range of acousto-ultrasonic frequencies. Presently, electronic devices are widely employed in commercial applications for …


U.S. Billion-Ton Update: Biomass Supply For A Bioenergy And Bioproducts Industry, Robert D. Perlack, Laurence M. Eaton, Anthony F. Turhollow Jr., Matt H. Langholtz, Craig C. Brandt, Mark E. Downing, Robin L. Graham, Lynn L. Wright, Jacob M. Kavkewitz, Anna M. Shamey, Richard G. Nelson, Bryce J. Stokes, William L. Rooney, David J. Muth Jr., J. Richard Hess, Jared M. Abodeely, Chad Hellwinckel, Danial De La Torre Ugarte, Daniel C. Yoder, James P. Lyon, Timothy G. Rials, Timothy A. Volk, Thomas S. Buchholz, Lawrence P. Abrahamson, Robert P. Anex, Thomas B. Voigt, William Berguson, Don E. Riemenschneider, Douglas Karlen, Jane M. F. Johnson, Robert B. Mitchell, Kenneth P. Vogel, Edward P. Richard Jr., John Tatarko, Larry E. Wagner, Kenneth E. Skog, Patricia K. Lebow, Dennis P. Dykstra, Marilyn A. Buford, Patrick D. Miles, D. Andrew Scott, James H. Perdue, Robert B. Rummer, Jamie Barbour, John A. Stanturf, David B. Mckeever, Ronald S. Zalesny Jr., Edmund A. Gee, P. Daniel Cassidy, David Lightle Dec 2015

U.S. Billion-Ton Update: Biomass Supply For A Bioenergy And Bioproducts Industry, Robert D. Perlack, Laurence M. Eaton, Anthony F. Turhollow Jr., Matt H. Langholtz, Craig C. Brandt, Mark E. Downing, Robin L. Graham, Lynn L. Wright, Jacob M. Kavkewitz, Anna M. Shamey, Richard G. Nelson, Bryce J. Stokes, William L. Rooney, David J. Muth Jr., J. Richard Hess, Jared M. Abodeely, Chad Hellwinckel, Danial De La Torre Ugarte, Daniel C. Yoder, James P. Lyon, Timothy G. Rials, Timothy A. Volk, Thomas S. Buchholz, Lawrence P. Abrahamson, Robert P. Anex, Thomas B. Voigt, William Berguson, Don E. Riemenschneider, Douglas Karlen, Jane M. F. Johnson, Robert B. Mitchell, Kenneth P. Vogel, Edward P. Richard Jr., John Tatarko, Larry E. Wagner, Kenneth E. Skog, Patricia K. Lebow, Dennis P. Dykstra, Marilyn A. Buford, Patrick D. Miles, D. Andrew Scott, James H. Perdue, Robert B. Rummer, Jamie Barbour, John A. Stanturf, David B. Mckeever, Ronald S. Zalesny Jr., Edmund A. Gee, P. Daniel Cassidy, David Lightle

Douglas L Karlen

The Report, Biomass as Feedstock for a Bioenergy and Bioproducts Industry: The Technical Feasibility of a Billion-Ton Annual Supply (generally referred to as the Billion-Ton Study or 2005 BTS), was an estimate of “potential” biomass within the contiguous United States based on numerous assumptions about current and future inventory and production capacity, availability, and technology. In the 2005 BTS, a strategic analysis was undertaken to determine if U.S. agriculture and forest resources have the capability to potentially produce at least one billion dry tons of biomass annually, in a sustainable manner—enough to displace approximately 30% of the country’s present petroleum …


Probing The Roles Of Polymeric Separators In Lithium-Ion Battery Capacity Fade At Elevated Temperatures, Jianchao Chen, Yongda Yan, Tao Sun, Yue Qi, Xiaodong Li Dec 2015

Probing The Roles Of Polymeric Separators In Lithium-Ion Battery Capacity Fade At Elevated Temperatures, Jianchao Chen, Yongda Yan, Tao Sun, Yue Qi, Xiaodong Li

Xiaodong Li

The high temperature mechanical property of separators is very important for safety of lithium-ion batteries. However, the mechanical integrity of polymeric separators in lithium-ion batteries at elevated temperatures is still not well characterized. In this paper, the temperature dependent micro-scale morphology change of PP (polypropylene)-PE (polyethylene)-PP sandwiched separators (Celgard 2325) was studied by in-situ high temperature surface imaging using an atomic force microscope (AFM) coupled with power spectral density (PSD) analysis and digital image correlation (DIC) technique. Both PSD and DIC analysis results show that the PP phase significantly closes its pores by means of dilation of the nanofibrils surrounding …


Probing The Roles Of Polymeric Separators In Lithium-Ion Battery Capacity Fade At Elevated Temperatures, Jianchao Chen, Yongda Yan, Tao Sun, Yue Qi, Xiaodong Li Dec 2015

Probing The Roles Of Polymeric Separators In Lithium-Ion Battery Capacity Fade At Elevated Temperatures, Jianchao Chen, Yongda Yan, Tao Sun, Yue Qi, Xiaodong Li

Xiaodong Li

The high temperature mechanical property of separators is very important for safety of lithium-ion batteries. However, the mechanical integrity of polymeric separators in lithium-ion batteries at elevated temperatures is still not well characterized. In this paper, the temperature dependent micro-scale morphology change of PP (polypropylene)-PE (polyethylene)-PP sandwiched separators (Celgard 2325) was studied by in-situ high temperature surface imaging using an atomic force microscope (AFM) coupled with power spectral density (PSD) analysis and digital image correlation (DIC) technique. Both PSD and DIC analysis results show that the PP phase significantly closes its pores by means of dilation of the nanofibrils surrounding …


A Platinum Nanowire Network As A Highly Effective Current Collector For Intermediate Temperature Solid Oxide Fuel Cells, Hanping Ding, Xingjian Xue Dec 2015

A Platinum Nanowire Network As A Highly Effective Current Collector For Intermediate Temperature Solid Oxide Fuel Cells, Hanping Ding, Xingjian Xue

Xingjian "Chris" Xue

We report the fabrication and evaluation of a platinum nanowire network as a highly efficient current collector for solid oxide fuel cells (SOFCs). The ink of carbon-black supported platinum nanoparticles was sprayed onto the cathode. After firing, the carbon black was oxidized and disappeared as carbon dioxide gas while the platinum nanoparticles connect with one another, forming a tree-branch-like nanowire network. The diameters of the nanowires range from 100 nm to 400 nm. Compared to a conventional platinum paste current collector, the polarization resistance of the PrBaCo2O5+δ (PBCO) cathode with a nanowire current collector was reduced …


A Platinum Nanowire Network As A Highly Effective Current Collector For Intermediate Temperature Solid Oxide Fuel Cells, Hanping Ding, Xingjian Xue Dec 2015

A Platinum Nanowire Network As A Highly Effective Current Collector For Intermediate Temperature Solid Oxide Fuel Cells, Hanping Ding, Xingjian Xue

Xingjian "Chris" Xue

We report the fabrication and evaluation of a platinum nanowire network as a highly efficient current collector for solid oxide fuel cells (SOFCs). The ink of carbon-black supported platinum nanoparticles was sprayed onto the cathode. After firing, the carbon black was oxidized and disappeared as carbon dioxide gas while the platinum nanoparticles connect with one another, forming a tree-branch-like nanowire network. The diameters of the nanowires range from 100 nm to 400 nm. Compared to a conventional platinum paste current collector, the polarization resistance of the PrBaCo2O5+δ (PBCO) cathode with a nanowire current collector was reduced by 44% at 650 …


Design Of A Tandem Rotor Hovering Vehicle, Brent Kostich Dec 2015

Design Of A Tandem Rotor Hovering Vehicle, Brent Kostich

Honors Theses

An investigation of thrust vectoring and an examination of existing tandem rotor dynamics were used to develop a structural body for a tandem rotor vehicle, derive the equations of motion of the system, and simulate a dynamic model of the vehicle. A vehicle prototype was constructed while further application of remote control capabilities, flight testing, and control development were researched. The dynamic simulation was based on a linear model of the system so as to open the possibility of implementing a control system. The simulation results show that thrust synchronization yields a predictable motion response. The prototype constructed did not …


Design And Fabrication Of An Instrumented Cane For The Blind, Aaron Dean Dec 2015

Design And Fabrication Of An Instrumented Cane For The Blind, Aaron Dean

Honors Theses

The most commonly used tool for navigation by the blind is the white cane. A greater understanding is essential in improving the design and performance of these canes. An existing cane was modified with integrated force and acceleration sensors, in order to study the relation between cane vibration characteristics and obstacle or drop-off detection. Data was gathered by these sensors, and then transmitted wirelessly to a computer workstation, where it was recorded and analyzed. Exertion of the forearm muscles was also measured. Care was taken to insure that the cane sensors and transmitter are ergonomically unobtrusive for the user. The …


Modeling And Simulation Of Micro Electrical Discharge Machining Process, Bai Shao Dec 2015

Modeling And Simulation Of Micro Electrical Discharge Machining Process, Bai Shao

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

Micro parts and systems are playing crucial roles in the area of semiconductor, biomedical device, micro fluid devices, automotive, aerospace and so forth. Micro manufacturing is one of the most important technologies in realizing miniaturization. Compared to other micro manufacturing methods, micro-EDM is drawing lots of attention due to its ability to machine complex 3D parts regardless of the hardness of the workpiece material.

Micro-EDM is the cumulative result of numerous single discharges; therefore, it is crucial to understand the single discharge material removal process in micro-EDM. However, due to the stochastic nature and complex process mechanism, micro-EDM, including its …


Spectrally-Accurate Algorithm For Flows In 3-Dimensional Rough Channels, Md Nazmus Sakib Dec 2015

Spectrally-Accurate Algorithm For Flows In 3-Dimensional Rough Channels, Md Nazmus Sakib

Electronic Thesis and Dissertation Repository

In this work a spectrally accurate algorithm has been developed for the simulation of three-dimensional flows bounded by rough walls. The algorithm is based on the velocity-vorticity formulation and uses the concept of Immersed Boundary Conditions (IBC) for the enforcement of the boundary conditions. The flow domain is immersed inside a fixed computational domain. The geometry of the boundaries is expressed in terms of double Fourier expansions and boundary conditions enter the algorithm in the form of constraints. The spatial discretization uses Fourier expansions in the stream-wise and span-wise directions and Chebyshev expansions in the wall-normal direction. The algorithm can …


Independency Of Elasticity On Residual Stress Of Room Temperature Rolled Stainless Steel 304 Plates For Structure Materials, Parikin Parikin, David Allen Dec 2015

Independency Of Elasticity On Residual Stress Of Room Temperature Rolled Stainless Steel 304 Plates For Structure Materials, Parikin Parikin, David Allen

Makara Journal of Technology

Mechanical strengths of materials are widely expected in general constructions of any building. These properties depend on its formation (cold/hot forming) during fabrication. This research was carried out on cold-rolled stainless steel (SS) 304 plates, which were deformed to 0, 34, 84, and 152% reduction in thickness. The tests were conducted using Vickers method. Ultra micro indentation system (UMIS) 2000 was used to determine the mechanical properties of the material, i.e.: hardness, modulus elasticity, and residual stresses. The microstructures showed lengthening outcropping due to stress corrosion cracking for all specimens. It was found that the tensile residual stress in a …


Effect Of Fly Ash Fortification In The Manufacture Process Of Making Concrete Towards Characteristics Of Concrete In Sulfuric Acid Solution, Asep Handaya Saputra, Muhammad Shohibi, Masatoshi Kubouchi Dec 2015

Effect Of Fly Ash Fortification In The Manufacture Process Of Making Concrete Towards Characteristics Of Concrete In Sulfuric Acid Solution, Asep Handaya Saputra, Muhammad Shohibi, Masatoshi Kubouchi

Makara Journal of Technology

Fly ash is a silica or alumino silica material that can be used as a constituent of cement in the concrete manufacturing process. Utilization of fly ash aims to improve durability and minimize the reduction of concrete’s compressive strength exposed to an acidic environment, which can be achieved through the pozzolanic reaction of fly ash with Ca(OH)2 within concrete. The reduced content of Ca(OH)2 through pozzolanic reaction will minimize the tendency of ettringite formation (compounds that cause deterioration and decrease the compressive strength of concrete). In order to determine the relation between fly ash replenishment into concrete with concrete’s characteristics …


Improvement Of Quality Of Carica Papaya L. With Clove Oil As Preservative In Edible Coating Technology, Eny Kusrini, Anwar Usman, Chrispine Deksita Wisakanti, Rita Arbianti, Dedy Alharis Nasution Dec 2015

Improvement Of Quality Of Carica Papaya L. With Clove Oil As Preservative In Edible Coating Technology, Eny Kusrini, Anwar Usman, Chrispine Deksita Wisakanti, Rita Arbianti, Dedy Alharis Nasution

Makara Journal of Technology

We have studied utilization of essential clove oil, extracted from clove buds by hydrodistillation, as preservative in edible packaging technology. Preservative of essential clove oil was applied on chopped papaya fruits by using two methods, namely spray and brush. The effects of concentration of clove oil from 0.05 to 0.20% on the preservation of papaya fruits (Carica papaya L.) at room temperature (25 °C) were also evaluated. Physicochemical and in vitro microbiological activities on the papaya fruits that were stored at 25 oC and 85-90% relative humidity were investigated in details. The results indicate that the clove oil at concentration …


Oxidation Process Of H 2 O /Uv For Cod Reduction Of Wastewater From Soybean Tofu Production, Komala Pontas, Abrar Muslim Dec 2015

Oxidation Process Of H 2 O /Uv For Cod Reduction Of Wastewater From Soybean Tofu Production, Komala Pontas, Abrar Muslim

Makara Journal of Technology

Chemical Oxygen Demand (COD) reduction of wastewater from soybean tofu production was studied by conducting advanced oxidation process (AOP) using hydrogen peroxide with UV radiation catalysts in a closed cylindrical glass reactor. The hydroxyl radical (*OH) concentration from H2O2 decomposition was modeled, and exponential trends were found for the *OH concentration over radiation time and operation temperature. As a result, it was found that the maximal *OH concentration was 0.209 mol L-1 at 240 minutes and 50 °C. The *OH concentration exponentially increased following rise in operation temperature. The H2O2/UV AOP application reduced COD concentration to approximately 42.41% from 10,545 …