Engineering Commons^™

Synthesis And Characterization Of Microporous And Mesoporous Catalysts For Shale Gas Upgrading, Danesh Contractor, Ravi Joshi, Rajamani Gounder

The Summer Undergraduate Research Fellowship (SURF) Symposium

The petroleum industry is gradually shifting from using naphtha to ethane as its feedstock and new ethane steam crackers are being built. Using ethane as a feedstock produces more ethene and less co-products such as propene, aromatics and C4 alkenes. Thus, the shift in feedstock will reduce the availability of these co-products. Developing methods for the interconversion of alkenes, and specifically using ethene as a reactant, can solve this problem.

This project focuses on synthesis and characterization of zeolites with the BEA framework topology, and their nickel exchanged versions as potential ethene dimerization catalysts. In future work, these materials will …

Energy Measurement Of Spdy Protocol On Mobile Platform, Zisheng Liao, Ashiwan Sivakumar, Sanjay Rao

The Summer Undergraduate Research Fellowship (SURF) Symposium

The past few years have witnessed an explosive growth in mobile Internet data traffic with web browsing being one of the key activities on mobile devices. There is tremendous interest in optimizing mobile web. In this regard, a new protocol called SPDY was introduced by Google to augment web browsing, however it's impact on the device energy consumption is not clearly understood. In this work we evaluate the energy characteristics of SPDY-based web browsing on mobile devices. In order to measure the energy consumption of web activities, we use AT&T’s ARO [1]. This tool is widely accepted and used by …

Radiation Measurements And Data Analysis Of Turbulent Premixed Lean Flame, Yunzhe Yang, Dong Han, Jay P. Gore

The Summer Undergraduate Research Fellowship (SURF) Symposium

An accurate understanding of the radiation transfer in turbulent premixed lean flame is critical for improving energy efficiencies and reducing emissions such as nitric oxide and soot. Radiation measurement is an effective and nonintrusive way to study the radiation properties of turbulent premixed lean flames. In this study, a high-speed infrared camera was utilized to measure the planar radiation from turbulent premixed lean flames under different conditions. Time-dependent flame images were acquired and radiation statistics were calculated and compared to investigate the effects of equivalence ratio, heat release rate, hydrogen pilot flame rate, and co-flow rate on the radiation intensity …

The Role Of Surface Area In Catalytic Gasification Of Biomass, Elizabeth A. Wachs, Nitish Kumar, Indraneel Sircar, Prithviraja Basak, Jay P. Gore Phd

The Summer Undergraduate Research Fellowship (SURF) Symposium

Gasification of biomass has the potential to provide a carbon-negative source of liquid fuels. The current limited use of gasification is due in part to the high temperatures necessary to achieve high conversion levels. These temperatures can be lowered by the use of catalysts, but the mechanisms by which catalysts affect the reaction rate are not fully understood. Here, the structural component of potassium carbonate’s role in the gasification process was examined. Samples of pinewood sawdust were impregnated with potassium carbonate, then pyrolyzed with N2 in a fixed bed reactor at 750°C (heater thermocouple reading). Half of the char was …

Engineering Leadership Assessment Tool Profile, Karan Sharma, Monique Ross, Monica F. Cox

The Summer Undergraduate Research Fellowship (SURF) Symposium

Numerous studies have been conducted stressing the importance of developing the professional skillset of engineers. This need has been further highlighted by the Engineering Criteria 2000 and by the National Academy of Engineers (Kumar and Hsiao, 2007, p. 19). Having realised the need to develop the professional skillset of engineers such as leadership, interpersonal skills, teamwork and communication, universities have started incorporating methods to hone these skills in their courses. However in today’s competitive world, every practice needs to be assessed and measured for accountability and effectiveness. Engineering education is no exception to this rule. There needs to be a …

Investigation Of Fracture And Healing Behavior Of Thermoreversible Gels Via Oscillation Rheology, Krithika Subramaniam, Travis Thornell, Kendra Erk

The Summer Undergraduate Research Fellowship (SURF) Symposium

Thermoreversible gels have the unique ability to self-heal, or repair themselves, once they are fractured. They are physically cross-linked, thus providing them with the capability to reform their broken bonds as a function of temperature. The objective of this project is to determine the extent of the gels’ recovery. If self-healing does in fact occur, these gels can be applied in various industries, including medicine for drug delivery or paints and coatings. The tri-block polymer poly(methyl methacrylate)-poly(n-butyl acrylate)-poly(methyl methacrylate) (PMMA-PnBA-PMMA) was heated and stirred with 2-ethyl-1-hexanol to create a polymer gel. Through the use of a rheometer, a shear stress …

Simulating Nanoscale Optics In Photovoltaics With The S-Matrix Method, Dalton Chaffee, Xufeng Wang, Peter Bermel

The Summer Undergraduate Research Fellowship (SURF) Symposium

In the push to build high-efficiency solar cells with less materials usage, thin-film solar cells have attracted an increasing amount of interest. Thin films are particularly attractive if they could exhibit light trapping and photon recycling capabilities exceeding those of traditional wafer-based cells. Recent work by Alta Devices demonstrating a record single-junction efficiency of 28.8% with a gallium arsenide thin film cell shows the potential. However, most existing simulation tools do not handle these properties well -- particularly photon recycling. In this work, we develop an improved solar cell simulation tool to accurately predict thin-film performance. It is based on …

Preliminary Testing Of Plasma-Induced Combustion, Ahmed Thalib Razi, Carson Slabaugh, Robert Lucht

The Summer Undergraduate Research Fellowship (SURF) Symposium

Plasma-induced combustion (PIC) has been shown to improve the reliability, efficiency, and delay time of ignition in flight systems like augmentors and scramjets. These high-velocity systems are mostly used in military applications, and improvement may help commercial viability. To understand this chemical process, the concentration of radicals, particularly H radicals, must be tracked through the flame using laser diagnostics. This requires a steady source of plasma-assisted combustion to be secured and well-understood. A plasma torch flowing partially premixed air and methane was installed and successfully operated, and preliminary testing was carried out. Primarily it was observed that PIC created stable …

Synthesis And Thermoelectric Properties Of Cusbs2, Tianyue Gao, Haiyu Fang, Yue Wu

The Summer Undergraduate Research Fellowship (SURF) Symposium

Copper antimony sulfide, CuSbS2 nanoparticles have a large potential of being a good thermoelectric material because they are made up of earth abundant elements. Thermoelectric materials can convert thermal energy into electricity, so that the wasted energy can be saved. Also, by using this earth abundant material, we can make thermoelectric materials much cheaper. The hypothesis of this study is that CuSbS2 could have a large Seebeck coefficient, one of the most important factors of thermoelectric materials, because of the complexity of its band structure. The other hypothesis is that thermal transport could be significantly suppressed through nanostructuring. There are …

Thermal Properties Of Soft Nanomaterials: Thermal Measurement Design, Yu Han, Meng Pan, Amy Marconnet, Collier Miers

The Summer Undergraduate Research Fellowship (SURF) Symposium

Soft materials like hydrogels have multiple tunable material properties because of their unique structures. Due to the ability to respond to stimuli like temperature or chemical environment, they have numerous applications in different fields like delivering drugs inside the human body and other medical uses. Details of the thermal transport mechanisms, as well as the overall thermal properties, are critical for a variety of applications. Multi-property measurements elucidate the underlying transport mechanisms in the soft materials. This research demonstrates a new methodology of measuring thermal properties of soft materials. This work uses the 3w method [1,2] for measuring the thermal …

Social Media Analytics Reporting Toolkit, Yuchen Cui, Junghoon Chae, David Ebert

The Summer Undergraduate Research Fellowship (SURF) Symposium

With the fast growth of social media services, vast amount of user-generated content with time-space stamps are produced everyday. Considerable amount of these data are publicly available online, some of which collectively convey information that are of interest to data analysts. Social media data are dynamic and unstructured by nature, which makes it very hard for analysts to efficiently and effectively retrieve useful information. Social Media Analytics Reporting Toolkit (SMART), a system developed at Purdue VACCINE lab, aims to support such analyzing. The current framework collects real-time Twitter messages and visualizes volume densities on a map. It uses Latent Dirichilet …

Comparison Of Thermal And Γ-Photon Induced Degradation In Polylactic Acid For Potential As A Solid-State Radiation Detector, Nathan M. Boyle, Alex Bakken, Rusi P. Taleyarkhan

The Summer Undergraduate Research Fellowship (SURF) Symposium

Degradation of the biopolymer Polylactic Acid, both thermally and through irradiation will cause physical changes in the material. These changes can be used in applications such as adhesives and sealants or in medical applications, but the primary focus of this study is for use as a solid-state radiation detector. A literature review shows that current research has been focused on thermal and γ-photon degradation in PLA but the physical characteristics such as melting temperature, latent heat of fusion, and composition of molecular bonds have not been compared in the same study. This study focuses on how thermal properties of PLA …

The Role Of Metal Oxide Layers In The Sensitivity Of Lactate Biosensors Subjected To Oxygen-Limited Conditions, Elizabeth Andreasen, Lia Stanciu, Aytekin Uzunoglu

The Summer Undergraduate Research Fellowship (SURF) Symposium

Amperometric lactate biosensors are used to detect lactate concentration in blood and tissues, which is integral in identifying cyanide poisoning, septic shock, and athletic condition. The construction of lactate biosensors with high sensitivity, selectivity, and stability is imperative to diagnose and determine these medical conditions. Lactate detection is currently limited to oxygen-rich environments due to the fact that oxygen is a limiting factor in the lactate reaction. To circumvent this problem, researchers have developed mediators or alternate, oxygen-free enzymes to improve sensitivity. In our study, ceria (CeO₂) with high oxygen storage capacity (OSC) was introduced to the enzyme …

Learning From Earthquakes: 2014 Napa Valley Earthquake Reconnaissance Report, Erica Fischer

Lyles School of Civil Engineering Graduate Student Reports

Structural damage was observed during reconnaissance after the 2014 South Napa Earthquake, and included damage to wine storage and fermentation tanks, collapse of wine storage barrel racks, unreinforced masonry building partial or full collapse, and residential building damage. This type of damage is not unique to the South Napa Earthquake, and was observed after other earthquakes such as the 1977 San Juan Earthquake, and the 2010 Maule Earthquake. Previous research and earthquakes have demonstrated the seismic performance of cylindrical fluid-filled tanks is controlled by both the tank and the sloshing motion of the liquid inside. Unlike building structures, steel tanks …

Right Sizes Of Nano- And Microstructures For High-Performance And Rigid Bulk Thermoelectrics, Hongchao Wang, Je-Hyeong Bahk, Chanyoung Kang, Junphil Hwang, Kangmin Kim, Jungwon Kim, Peter Burke, John E. Bowers, Arthur C. Gossard, Ali Shakouri, Woochul Kim

Birck and NCN Publications

In this paper, we systematically investigate three different routes of synthesizing 2% Na-doped PbTe after melting the elements: (i) quenching followed by hot-pressing (QH), (ii) annealing followed by hot-pressing, and (iii) quenching and annealing followed by hot-pressing. We found that the thermoelectric figure of merit, zT, strongly depends on the synthesis condition and that its value can be enhanced to similar to 2.0 at 773 K by optimizing the size distribution of the nanostructures in the material. Based on our theoretical analysis on both electron and thermal transport, this zT enhancement is attributed to the reduction of both the lattice …

Thermal Interfacial Transport In The Presence Of Ballistic Heat Modes, Bjorn Vermeersch, Amr M.S. Mohammed, Gilles Pernot, Yee Rui Koh, Ali Shakouri

Birck and NCN Publications

Thermal interface (Kapitza) resistance expresses how hard it is for heat to flow across material junctions inside multilayer structures. This quantity plays a crucial role in the thermal performance of nanoscale devices but is still poorly understood. Here we show that conventional Fourier-based metrology overestimates metal/semiconductor resistances by up to threefold due to misinterpretation of ballistic heat flow modes. We achieve improved identification and a different physical insight with a truncated Levy formalism. This approach properly distinguishes interfacial dynamics from nearby quasiballistic heat flow suppression in the semiconductor. Unlike conventionally extracted values, interface resistances obtained with our new approach are …

Development Of Improved Electrodeposition Method For Repair Of Reinforced Concrete Structures, Takahiro Nishida, Nobuaki Otsuki, Atsushi Saito

International Conference on Durability of Concrete Structures

Deterioration of reinforced concrete members and their repair methods have been reported in various concrete published reports. Electrodeposition method is one of these repair methods for repairing deteriorated concrete members using an electrochemical mechanism. The purposes of the electrodeposition method are to fill cracks in concrete and to coat the concrete surface by electrodeposits of chemical compounds. This can be accomplished by passing a weak direct current (1.0–3.0 A/m² of concrete surface area) between a reinforcing steel bar (cathode) in concrete and an external electrode (anode) located in an external solution near the concrete surface. This method also accomplishes …

Behavior Of Cfrp Plate In Simulated Iccp System Of Concrete Structures, Jihua Zhu, Miaochang Zhu, Ningxu Han, Feng Xing, Wei Liu, Luca Bertolini

International Conference on Durability of Concrete Structures

An innovative effort was made to utilize carbon fiber reinforced polymer (CFRP) plate as an anode in impressed current cathodic protection (ICCP) of reinforced concrete structure. The feasibility was explored by bonding CFRP strips to concrete and then applying protection current through CFRP strips to steel rebar in concrete. Service life and performance of CFRP plate were investigated in simulated ICCP systems with various configurations. Steel potential results confirmed that the steel rebar in concrete maintained at a satisfactory level with the applied protection current. It is shown that CFRP strips can be successfully used in various solutions as an …

Water–Binder Ratio Monitoring As A Quality Control Tool For The High-Performance Concrete Used In The Construction Of The Submerged Tunnel, Junjie Zeng, Shengnian Wang, Weiqing Lv, Quanke Su, Zhonghe Shui

International Conference on Durability of Concrete Structures

The designed service life of Hong Kong-Zhuhai-Macao Bridge is 120 years. Concrete quality control for the submerged tunnel of the project is an important work to assure the designed service life. This article is to present an advanced concrete performance prediction method based on water–binder ratio (w/b) monitoring, which is used to serve for concrete quality control. During experiments in the lab, the w/b of submerged tunnel concrete mix proportion was designed to fluctuate up and down, while the other compositions were kept constant. Concretes with different w/b were prepared. The w/b of fresh concrete was tested, followed by preparation …

Heavy Metal Desorption From Cement Hydrates Caused By Chloride Solutions, Akihiko Hayashi, Yuko Ogawa, Kenji Kawai

International Conference on Durability of Concrete Structures

After the demolition of concrete structures, it is expected to recycle the whole of the demolished concrete. As of now, however, it is difficult to recycle the fine powders generated in the processes of demolition of concrete and manufacture of recycled aggregate because these powders may contain heavy metals exceeding the soil environmental standard, and such powders are disposed finally. It is well known that heavy metals are easily adsorbed on cement hydrates. To promote the total recycling of demolished concrete, it is important to remove adsorbed heavy metals from the fine powders easily. This article tried to gain a …

Durability Assessment Of Concrete Structures In Hzm Sea Link Project For Design Life Of 120 Years, Kefei Li, Q. W. Li, Q. M. Zhang, Z. H. Fan, L. H. Yang

International Conference on Durability of Concrete Structures

This article presents the durability assessment of the concrete structures in the ongoing Hong Kong–Zhuhai–Macao (HZM) sea link project for a design service life of 120 years. During the preliminary study phase, the durability design of concrete structures has been performed by a model-based method with a partial factor scheme for chloride-induced corrosion process. On the basis of the actual design options adopted in the detailed design phase, the durability assessment of concrete structures is performed for the achieved durability and reliability levels. For this purpose, the durability assessment retains the same model for chloride-induced corrosion as in the preliminary …

Effect Of Drying Rate On Shrinkage Of Alkali-Activated Slag Cements, Hailong Ye, Christopher Cartwright, Farshad Rajabipour, Aleksandra Radlińska

International Conference on Durability of Concrete Structures

The volumetric instability of alkali-activated slag (AAS) binders has raised concerns and impeded the acceptance of this Portland cement-free material. The objective of this article is to characterize the influence of drying rate on drying shrinkage behavior of AAS mortars to better understand the mechanisms responsible for its large shrinkage deformation. A series of four AAS mortar mixtures with varying activator composition, as well as a reference Portland cement mortar, was cast and dried at different relative humidities, that is, 30, 50, 70, and 85% RH. Drying took place inside nitrogen-purged environmental chambers for the purpose of eliminating the contribution …

Using Modified Mortar-Bar Test Method To Access The Effects Of Deicers On Expansion Of Mortars With And Without Reactive Aggregates, Yi-Cheng Chiu, Jan Olek

International Conference on Durability of Concrete Structures

The influence of deicing chemicals on alkali reactivity of aggregates is still an area of active research. The potential alkali reactivity of aggregates is often tested using the ASTM C1260 method. This research used the modified ASTM C1260 to test the potential alkali reactivity of aggregates. The modification included replacing the standard 1N sodium hydroxide (NaOH) used in ASTM C1260 with eutectic concentrations of the three common chloridebased deicing chemicals: sodium chloride (NaCl), magnesium chloride (MgCl₂), and calcium chloride (CaCl₂). The results showed that the mortar bars with reactive aggregate (Jobe sand) stored in NaCl solution …

Performance Evaluation Of Sugarcane Bagasse Ash-Based Cement For Durable Concrete, A. Bahurudeen, Manu Santhanam

International Conference on Durability of Concrete Structures

Sugarcane bagasse ash (SCBA) is obtained as a by-product from cogeneration combustion boilers in sugar industries. Bagasse ash is mainly composed of reactive silica and can be used as pozzolanic material in concrete. Previous studies have reported that the utilization of SCBA as pozzolanic material in concrete can significantly improve its performance. A comprehensive investigation of durability performance of bagasse ash in concrete is not available in existing literature. In all previous studies, raw bagasse ash was ground to cement fineness and directly used in the concrete for the performance evaluation, without suitable characterization. Development of SCBA-based Portland pozzolana cement …

Influence Of Fly Ash On Surface Chloride Concentration Under Shallow Immersion Condition, Jun Liu, Xiaodong Wang, Feng Xing, Ningxu Han

International Conference on Durability of Concrete Structures

In this paper, the influence of fly ash content on concrete surface chloride concentration was investigated through periodical tests of surface chloride concentration of concrete by immersing three kinds of concrete specimens in 5.0 wt.% sodium chloride solution. One kind of specimen is common concrete without fly ash, whereas the other two kinds of specimens are mixed with fly ash. The results show that the surface chloride ion concentration ranges from 0.295 to 0.777 wt.% for the immersed concrete samples in this study; in the initial stage of immersion, the concrete surface chloride ion concentration is affected by added fly …

The Analysis Of The Internal Forces In Strengthened Old Concrete Bridge Subject To Vehicular Load By Transforming Simply Supported Into Continuous System, Huanan He, Lijuan Xin

International Conference on Durability of Concrete Structures

In the past half century, large numbers of simply supported bridges were constructed in China; however, with the passing of years and the increase in the volume of transport, many of the bridges are out of normal service level and even gradually lose their bearing capacity due to overload or environmental influence. Therefore, some strengthening works have to be carried out in order for these old bridges to work well. Among the common strengthening methods, an efficient way to transform a simply supported into a continuous system is widely used in simply supported bridges with small or medium span. After …

Effects Of Stirrups On Bond Behavior Between Concrete And Corroded Steel Bars, Hongwei Lin, Yuxi Zhao, Ming Sun

International Conference on Durability of Concrete Structures

Steel corrosion leads to the deterioration of bond between concrete and steel bars. The serviceability and ultimate strength of concrete elements within RC structures are hence affected. Many researchers have studied the bond behavior of corroded steel bars. However, very few studies have investigated the effects of confinements on the degradation of bond strength. The present paper proposed a new kind of beam specimen based on which the effects of stirrups on degradation of bond were investigated. The test results proved that stirrups can effectively increase the bond strength between concrete and corroded steel bars.

Saturation Of Air Entrained Voids And Its Implication On The Transport Of Ionic Species In Concrete, Yiwen Bu, Jason Weiss

International Conference on Durability of Concrete Structures

Air entrainment is commonly used to improve the durability of concrete materials exposed to freezing and thawing. While the influence of air voids on freeze/thaw damage and salt scaling is frequently studied, the influence of entrained air voids on ionic transport has been studied less frequently. Since ionic transport in concrete materials relies on pore fluid as the medium of conduction, only saturated or partially saturated air voids participate in the transport processes. This paper discusses the conditions under which air voids could become saturated. Specifically, the saturation condition of entrained air voids in laboratory tests and in service is …

Visualization And Quantification Of Solute Diffusivity In Cracked Concrete By X-Ray Ct, Michael Henry, T. Sugiyama, I. S. Darma

International Conference on Durability of Concrete Structures

This paper explores the usage of microfocus X-ray computed tomography (CT) for visualization and quantification of diffusion phenomena in cracked concrete. Mortar specimens of varying shapes (prismatic and cylindrical), crack types (artificial and splitting tensile), and binder compositions (OPC and fly ash) were prepared. Cesium carbonate (Cs₂CO₃) was used as a tracer in the diffusion test because it has high X-ray absorption due to its high atomic number and thus contrasts with mortar and air voids in the CT images. Image processing and analysis was carried out to visualize and quantify the diffusion behavior in 3D …

Effect Of Blast Furnace Slag Powder And Fly Ash On Durability Of Concrete Mixed With Seawater, Nobuaki Otsuki, Takahiro Nishida, Chang Yi, Tomohiro Nagata, Hiroki Ohara

International Conference on Durability of Concrete Structures

According to the report of the United Nations, it is said that two-third of world population would be influenced by water shortage before 2050. To use fresh water effectively, the usage of seawater in concrete industry seems imperative. However, the usage of seawater as concrete material is prohibited in almost all the standards or specifications around the world. In this article, the usage of seawater as a material of concrete based on the results of experimental works and deterioration prediction was discussed. Especially, the effects of by-products such as blast furnace slag or fly ash on the durability of concrete …