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Articles 151 - 180 of 440

Full-Text Articles in Civil and Environmental Engineering

Development Of Domain Analysis For Determining Potential Pavement Damage, Angeli Gamez, Jaime Hernandez, Hasan Ozer, Imad L. Al-Qadi Sep 2018

Development Of Domain Analysis For Determining Potential Pavement Damage, Angeli Gamez, Jaime Hernandez, Hasan Ozer, Imad L. Al-Qadi

Civil and Environmental Engineering Faculty Research and Publications

A new approach for quantifying flexible pavement damage potential is proposed. The new method, domain analysis, utilizes multiaxial results from advanced finite element models to calculate the response of flexible pavements to tire loading. The output is a single scalar value, which is unique to a given pavement structure and loading configuration. The ability of the domain analysis to quantify bulk damage potential and overcome flaws of conventional approaches based on point responses is demonstrated by testing three case studies: (1) comparison of typical loading conditions of dual-tire assembly (DTA), new-generation wide-base tire (NG-WBT), and steer tire; (2) effect of …

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Concrete Pavement Blowup Considering Generalized Boundary Conditions, Jaime Hernandez, Imad L. Al-Qadi Sep 2018

Concrete Pavement Blowup Considering Generalized Boundary Conditions, Jaime Hernandez, Imad L. Al-Qadi

Civil and Environmental Engineering Faculty Research and Publications

An analytical expression for static stability of a rectangular slab with two simply supported and two elastically restrained edges is presented. The linear elastic isotropic slab can represent a rigid pavement resting on an elastic foundation and loaded by a uniform in-plane axial load per unit length along the edges. The partially restrained edges are connected to the ground by translational and rotational elastic springs; an appropriate magnitude of the springs can capture classical boundary conditions such as free, simply supported, and clamped edges. Results from classical boundary conditions and a finite-element model were used to validate the proposed stability …

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In Situ Strain And Damage Monitoring Of Gfrp Laminates Incorporating Carbon Nanofibers Under Tension, Yanlei Wang, Yongshuai Wang, Baoguo Han, Baolin Wan, Gaochuang Cai, Ruijuan Chang Jul 2018

In Situ Strain And Damage Monitoring Of Gfrp Laminates Incorporating Carbon Nanofibers Under Tension, Yanlei Wang, Yongshuai Wang, Baoguo Han, Baolin Wan, Gaochuang Cai, Ruijuan Chang

Civil and Environmental Engineering Faculty Research and Publications

In this study, conductive carbon nanofibers (CNFs) were dispersed into epoxy resin and then infused into glass fiber fabric to fabricate CNF/glass fiber-reinforced polymer (GFRP) laminates. The electrical resistance and strain of CNF/GFRP laminates were measured simultaneously during tensile loadings to investigate the in situ strain and damage monitoring capability of CNF/GFRP laminates. The damage evolution and conduction mechanisms of the laminates were also presented. The results indicated that the percolation threshold of CNFs content for CNF/GFRP laminates was 0.86 wt % based on a typical power law. The resistance response during monotonic tensile loading could be classified into three …

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Characteristics And Applications Of Biochars Derived From Wastewater Solids, Zhongzhe Liu, Simcha L. Singer, Yiran Tong, Lee Kimball, Erik Anderson, Matthew Hughes, Daniel Zitomer, Patrick J. Mcnamara Jul 2018

Characteristics And Applications Of Biochars Derived From Wastewater Solids, Zhongzhe Liu, Simcha L. Singer, Yiran Tong, Lee Kimball, Erik Anderson, Matthew Hughes, Daniel Zitomer, Patrick J. Mcnamara

Civil and Environmental Engineering Faculty Research and Publications

Pyrolysis is a thermochemical decomposition process that can be used to generate pyrolysis gas (py-gas), bio-oil, and biochar as well as energy from biomass. Biomass from agricultural waste and other plant-based materials has been the predominant pyrolysis research focus. Water resource recovery facilities also produce biomass, referred to as wastewater solids, that could be a viable pyrolysis feedstock. Water resource recovery facilities are central collection and production sites for wastewater solids. While the utilization of biochar from a variety of biomass types has been extensively studied, the utilization of wastewater biochars has not been reviewed in detail. This review compares …

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Uv-Based Advanced Oxidation Of P22 Bacteriophange And E. Coli Bacteria, Vincent Martino Jul 2018

Uv-Based Advanced Oxidation Of P22 Bacteriophange And E. Coli Bacteria, Vincent Martino

Master's Theses (2009 -)

Two novel, sustainable UV-LED advanced oxidation processes (AOPs) were evaluated for their ability to improve inactivation efficacy of P22 bacteriophage and E. coli bacteria. The first objective of this research was to determine the treatment efficacy of P22 bacteriophage and E. coli bacteria using UV-LED at wavelengths of 255, 265, and 285 nm. The UV-LED system demonstrated high inactivation potential for both contaminants at all wavelengths, suggesting it could be a potential alternative to typical low-pressure and medium-pressure mercury-based UV systems. Increased inactivation of both microorganisms was observed with decreasing wavelength (255>265>285 nm). As the peak UV absorbance …

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Biosolids-Derived Biochar For Triclosan Removal From Wastewater, Lee K. Kimbell, Yiran Tong, Brooke K. Mayer, Patrick J. Mcnamara Jun 2018

Biosolids-Derived Biochar For Triclosan Removal From Wastewater, Lee K. Kimbell, Yiran Tong, Brooke K. Mayer, Patrick J. Mcnamara

Civil and Environmental Engineering Faculty Research and Publications

Micropollutants, including antibiotics, hormones, pharmaceuticals, and personal care products, are discharged into the environment with liquid and solid effluent streams from water resource recovery facilities (WRRFs). The objective of this research was to determine whether biosolids-derived biochar (BS-biochar) could be used as a sorbent in continuous flow-through columns to remove micropollutants as a polishing step for wastewater treatment. Triclosan (TCS) was selected as a representative micropollutant due to frequent detection in liquid effluents, residual biosolids, and surface waters. Bench-scale column experiments were conducted to determine the effect of flow rate and competition due to the presence of other organic micropollutants …

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Driver Responses To Graphic-Aided Portable Changeable Message Signs In Highway Work Zones, Yilei Huang, Yong Bai May 2018

Driver Responses To Graphic-Aided Portable Changeable Message Signs In Highway Work Zones, Yilei Huang, Yong Bai

Civil and Environmental Engineering Faculty Research and Publications

Portable changeable message signs (PCMSs) have been employed in highway work zones as temporary traffic control devices. Various studies showed that adding graphics to PCMS messages can provide advantages to traditional text messages, such as increasing legibility and improving the understanding of elderly drivers. This article synthesizes the findings of a two-phase research project aimed to investigate driver responses to graphic-aided PCMSs. Different text and graphic-aided PCMSs representing roadwork and flagger were set up in the upstream of highway work zones, and speed data of more than 2,700 vehicles were collected with a series of five speed sensors to determine …

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The Impact Of Phosphorous Species On Dewaterability Of Wastewater Solids, Erik Anderson Apr 2018

The Impact Of Phosphorous Species On Dewaterability Of Wastewater Solids, Erik Anderson

Master's Theses (2009 -)

Phosphorus regulations are causing Water Resource Recovery Facilities (WRRFs) to implement new technologies to remove phosphorus (P) before they discharge liquid effluent. Enhanced Biological Phosphorus Removal (EBPR) is often employed to remove P from water. However, sludges from EBPR plants have shown decreases in dewaterability soon after EBPR was initiated. This decline in dewaterability is not well understood, nor is the best way to improve the dewatering EBPR sludge. Specifically, the role of different P species on sludge dewaterability is not well understood. Several laboratory experiments were conducted at the Marquette University Water Quality Center with the following objectives: i) …

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Anaerobic Co-Digestion Of Aqueous Liquid From Biosolids Pyrolysis, Seyedfatemeh Seyedi Apr 2018

Anaerobic Co-Digestion Of Aqueous Liquid From Biosolids Pyrolysis, Seyedfatemeh Seyedi

Master's Theses (2009 -)

Pyrolysis is a process to treat biosolids and recover energy. During pyrolysis, conversion of organic matter to energy-rich products yields biochar, py-gas, and pyrolysis liquids (aqueous phase and non-aqueous bio-oil). The aqueous pyrolysis liquid (APL), is a high-COD liquid with no apparent use that contains polycyclic aromatic hydrocarbons and nitrogen-containing compounds. One potential beneficial use of APL is as a co-digestate to produce more biogas for renewable energy from anaerobic digesters at municipal water resource recovery facilities. Some of the organics in APL may be converted to biomethane via anaerobic digestion under proper conditions. However, some APL organics are known …

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Effect Of Low Aeration And Heat Drying On Anaerobic Digester Performance And Microbial Community, Dylan Thomas Friss Apr 2018

Effect Of Low Aeration And Heat Drying On Anaerobic Digester Performance And Microbial Community, Dylan Thomas Friss

Master's Theses (2009 -)

This thesis describes three research projects on anaerobic digestion (AD) that investigated functional differences and relationships between microbial composition and digester function. Both archaeal and bacterial communities were characterized using high throughput (Illumina) sequencing technology with universal 16S rRNA gene primers. In the first project, limited aeration, and limited aeration with an aerotolerant enrichment culture were investigated as possible methods to increase digester functional performance in comparison to a strictly anaerobic control digester. No functional differences were observed at quasi-steady state between the limited aerated digester (LAD), limited aerated anaerobic digester augmented with an aerotolerant enrichment culture (LADE), and strictly …

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Micropollutant-Free Nutrient Recovery: Adsorption Of Micropollutants On Ion Exchangers And Biosolids-Derived Biochar, Yiran Tong Apr 2018

Micropollutant-Free Nutrient Recovery: Adsorption Of Micropollutants On Ion Exchangers And Biosolids-Derived Biochar, Yiran Tong

Dissertations (1934 -)

The presence of excessive nutrients in treated wastewater effluent is a growing concern in terms of water quality and ecological balance. Thus, removal of nutrients is of great interest. Moreover, the removed nutrients can be recovered in forms amenable for agricultural reuse, which yields a sustainable supply of nonrenewable phosphorus that can be used to support global food production. As nutrient recovery gains interest, it is essential that the products be free of harmful contaminants. One class of contaminants of great concern is organic micropollutants. To help address these issues, this study evaluated the fate and impact of micropollutants during …

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Educating And Developing Construction Professionals: Integrating The Co-Op Program With Construction Engineering Education, Yong Bai Mar 2018

Educating And Developing Construction Professionals: Integrating The Co-Op Program With Construction Engineering Education, Yong Bai

Civil and Environmental Engineering Faculty Research and Publications

No abstract provided.

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Fully Probabilistic Analysis Of Frp-To-Concrete Bonded Joints Considering Model Uncertainty, Dongming Zhang, Xiang-Lin Gu, Qian-Qian Yu, Hongwei Huang, Baolin Wan, Cheng Jiang Feb 2018

Fully Probabilistic Analysis Of Frp-To-Concrete Bonded Joints Considering Model Uncertainty, Dongming Zhang, Xiang-Lin Gu, Qian-Qian Yu, Hongwei Huang, Baolin Wan, Cheng Jiang

Civil and Environmental Engineering Faculty Research and Publications

This work presents a full reliability-based analysis framework for fiber-reinforced polymer(FRP)-to-concrete bonded joints considering model uncertainty. Eight frequently used bond strength models for FRP-to-concrete bonded joints were calibrated by defining a model factor. A total of 641 well-documented tests were considered. Four of the eight models had model factors that correlated with input design parameters and the systematic part of the model factor was removed by a regression equation f. By doing this type of characterization, all eight model factors could be comparatively uniform and described by lognormally distributed random variables. The merit of the uniform model uncertainties …

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Evaluation Of Continuous Monitoring As A Tool For Municipal Stormwater Management Programs, Walter M. Mcdonald, Randel L. Dymond, Vinod K. Lohani Feb 2018

Evaluation Of Continuous Monitoring As A Tool For Municipal Stormwater Management Programs, Walter M. Mcdonald, Randel L. Dymond, Vinod K. Lohani

Civil and Environmental Engineering Faculty Research and Publications

The purpose of this study is to evaluate the uncertainty attributable to inadequate temporal sampling of stormwater discharge and water quality, and understand its implications for meeting monitoring objectives relevant to municipal separate storm sewer systems (MS4s). A methodology is presented to evaluate uncertainty attributable to inadequate temporal sampling of continuous stormflow and water quality, and a case study demonstrates the application of the methodology to six small urban watersheds (0.8-6.8 km2) and six large rural watersheds (30-16,192 km2) in Virginia. Results indicate the necessity of high-frequency continuous monitoring for accurately capturing multiple monitoring objectives, including …

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Pretreatment And Anaerobic Co-Digestion Of Selected Phb And Pla Bioplastics, Nicholas John Norio Benn, Daniel Zitomer Jan 2018

Pretreatment And Anaerobic Co-Digestion Of Selected Phb And Pla Bioplastics, Nicholas John Norio Benn, Daniel Zitomer

Civil and Environmental Engineering Faculty Research and Publications

Conventional petroleum-derived plastics are recalcitrant to biodegradation and can be problematic as they accumulate in the environment. In contrast, it may be possible to add novel, biodegradable bioplastics to anaerobic digesters at municipal water resource recovery facilities along with primary sludge to produce more biomethane. In this study, thermal and chemical bioplastic pretreatments were first investigated to increase the rate and extent of anaerobic digestion. Subsequently, replicate, bench-scale anaerobic co-digesters fed synthetic primary sludge with and without PHB bioplastic were maintained for over 170 days. Two polyhydroxybutyrate (PHB), one poly(3-hydroxybutyrate-co-4-hydroxybutyrate) and one polylactic acid (PLA) bioplastic were investigated. Biochemical methane …

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Enhancing Frp-To-Concrete Bond Behavior By Epoxy Ribs, Cheng Jiang, Baolin Wan, John Omboko Jan 2018

Enhancing Frp-To-Concrete Bond Behavior By Epoxy Ribs, Cheng Jiang, Baolin Wan, John Omboko

Civil and Environmental Engineering Faculty Research and Publications

The bond between external bonding (EB) of fiber reinforced polymer (FRP) composite materials to concrete is the weakest link in the strengthened concrete flexural members. There are three mechanisms to transfer the interfacial shear between FRP and the concrete substrate, i.e., adhesion, interlocking and friction. This paper proposes a new approach by grooving on the concrete surface before applying epoxy to make epoxy ribs to increase interlocking. An experimental program was conducted to verify the effectiveness of the proposed epoxy ribs. Six grooves perpendicular to the fiber direction were cut on the bonding surface of the concrete blocks. The grooves …

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Effect Of Pyrolysis On The Removal Of Antibiotic Resistance Genes And Class I Integrons From Municipal Wastewater Biosolids, Lee Kimbell, Anthony D. Kappell, Patrick J. Mcnamara Jan 2018

Effect Of Pyrolysis On The Removal Of Antibiotic Resistance Genes And Class I Integrons From Municipal Wastewater Biosolids, Lee Kimbell, Anthony D. Kappell, Patrick J. Mcnamara

Civil and Environmental Engineering Faculty Research and Publications

Wastewater biosolids represent a significant reservoir of antibiotic resistance genes (ARGs). While current biosolids treatment technologies can reduce ARG levels in residual wastewater biosolids, observed removal rates vary substantially. Pyrolysis is an anoxic thermal degradation process that can be used to convert biosolids into energy rich products including py-gas and py-oil, and a beneficial soil amendment, biochar. Batch pyrolysis experiments conducted on municipal biosolids revealed that the 16S rRNA gene, the ARGs erm(B), sul1, tet(L), tet(O), and the integrase gene of class 1 integrons (intI1) were significantly reduced at pyrolysis temperatures ranging from 300–700 …

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Construction Engineering Education Committee: Past, Present, And Future, Yong Bai Jan 2018

Construction Engineering Education Committee: Past, Present, And Future, Yong Bai

Civil and Environmental Engineering Faculty Research and Publications

No abstract provided.

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Higher Education On Buildings: Case Study In The North Dakota Region, Houjun Yang, Malini Srivastava, Yanmei Xie, Yong Bai Dec 2017

Higher Education On Buildings: Case Study In The North Dakota Region, Houjun Yang, Malini Srivastava, Yanmei Xie, Yong Bai

Civil and Environmental Engineering Faculty Research and Publications

Because of the growing demand for local skilled professionals to improve the health, energy efficiency, and sustainability of residential and commercial buildings in North Dakota, this case study reports the current situation of higher education relating to buildings in the state’s vicinity, including Minnesota, Montana, North Dakota, and South Dakota. In this region, 116 programs relating to buildings were found in 41 postsecondary institutions, and both their majors and courses were then studied with frequency lists. The frequency information was analyzed over nine sets of curriculum areas at both graduate and undergraduate levels for the four states. After the current …

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Climate, Not Conflict, Explains Extreme Middle East Dust Storm, Anthony J. Parolari, Dan Li, Elie Bou-Zeid, Gabriel Katul, Shmuel Assouline Oct 2017

Climate, Not Conflict, Explains Extreme Middle East Dust Storm, Anthony J. Parolari, Dan Li, Elie Bou-Zeid, Gabriel Katul, Shmuel Assouline

Civil and Environmental Engineering Faculty Research and Publications

The recent dust storm in the Middle East (September 2015) was publicized in the media as a sign of an impending ‘Dust Bowl.’ Its severity, demonstrated by extreme aerosol optical depth in the atmosphere in the 99th percentile compared to historical data, was attributed to the ongoing regional conflict. However, surface meteorological and remote sensing data, as well as regional climate model simulations, support an alternative hypothesis: the historically unprecedented aridity played a more prominent role, as evidenced by unusual climatic and meteorological conditions prior to and during the storm. Remotely sensed normalized difference vegetation index demonstrates that vegetation cover …

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Hydrologic Transport Of Dissolved Inorganic Carbon And Its Control On Chemical Weathering, Salvatore Calabrese, Anthony J. Parolari, Amilcare Porporato Oct 2017

Hydrologic Transport Of Dissolved Inorganic Carbon And Its Control On Chemical Weathering, Salvatore Calabrese, Anthony J. Parolari, Amilcare Porporato

Civil and Environmental Engineering Faculty Research and Publications

Chemical weathering is one of the major processes interacting with climate and tectonics to form clays, supply nutrients to soil microorganisms and plants, and sequester atmospheric CO2. Hydrology and dissolution kinetics have been emphasized as factors controlling chemical weathering rates. However, the interaction between hydrology and transport of dissolved inorganic carbon (DIC) in controlling weathering has received less attention. In this paper, we present an analytical model that couples subsurface water and chemical molar balance equations to analyze the roles of hydrology and DIC transport on chemical weathering. The balance equations form a dynamical system that fully determines …

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A Comparative Life Cycle Assessment Between A Metered Dose Inhaler And Electric Nebulizer, Brandon Goulet, Lars E. Olson, Brooke K. Mayer Sep 2017

A Comparative Life Cycle Assessment Between A Metered Dose Inhaler And Electric Nebulizer, Brandon Goulet, Lars E. Olson, Brooke K. Mayer

Civil and Environmental Engineering Faculty Research and Publications

Life cycle assessment (LCA) evaluates the environmental impact of a product based on the materials and processes used to manufacture the item as well as the item’s use and disposal. The objective of this LCA was to evaluate and compare the environmental impact of a metered dose inhaler, specifically the Proventil® HFA inhaler (Merk & Co., Inc., Kenilworth, NJ, USA), and an electric nebulizer, specifically the DeVilbiss Pulmo-Aide® nebulizer (DeVilbiss, Port Washington, NY, USA). GaBi LCA software was used to model the global warming potential (GWP) of each product by using substantiated data and well-justified assumptions for the components, manufacturing, …

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Boom And Bust Carbon-Nitrogen Dynamics During Reforestation, Anthony J. Parolari, Megan L. Mobley, Allan R. Bacon, Gabriel Katul, Daniel Deb. Richter, Amilcare Porporato Sep 2017

Boom And Bust Carbon-Nitrogen Dynamics During Reforestation, Anthony J. Parolari, Megan L. Mobley, Allan R. Bacon, Gabriel Katul, Daniel Deb. Richter, Amilcare Porporato

Civil and Environmental Engineering Faculty Research and Publications

Legacies of historical land use strongly shape contemporary ecosystem dynamics. In old-field secondary forests, tree growth embodies a legacy of soil changes affected by previous cultivation. Three patterns of biomass accumulation during reforestation have been hypothesized previously, including monotonic to steady state, non-monotonic with a single peak then decay to steady state, and multiple oscillations around the steady state. In this paper, the conditions leading to the emergence of these patterns is analyzed. Using observations and models, we demonstrate that divergent reforestation patterns can be explained by contrasting time-scales in ecosystem carbon-nitrogen cycles that are influenced by land use legacies. …

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Increasing Atmospheric Humidity And Co2 Concentration Alleviate Forest Mortality Risk, Yanlan Liu, Anthony J. Parolari, Mukesh Kumar, Chang-Wei Huang, Gabriel Katul, Amilcare Porporato Sep 2017

Increasing Atmospheric Humidity And Co2 Concentration Alleviate Forest Mortality Risk, Yanlan Liu, Anthony J. Parolari, Mukesh Kumar, Chang-Wei Huang, Gabriel Katul, Amilcare Porporato

Civil and Environmental Engineering Faculty Research and Publications

Climate-induced forest mortality is being increasingly observed throughout the globe. Alarmingly, it is expected to exacerbate under climate change due to shifting precipitation patterns and rising air temperature. However, the impact of concomitant changes in atmospheric humidity and CO2 concentration through their influence on stomatal kinetics remains a subject of debate and inquiry. By using a dynamic soil–plant–atmosphere model, mortality risks associated with hydraulic failure and stomatal closure for 13 temperate and tropical forest biomes across the globe are analyzed. The mortality risk is evaluated in response to both individual and combined changes in precipitation amounts and their seasonal …

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A Shared Ontology Approach To Semantic Representation Of Bim Data, Mehrdad Niknam, Saeed Karshenas Aug 2017

A Shared Ontology Approach To Semantic Representation Of Bim Data, Mehrdad Niknam, Saeed Karshenas

Civil and Environmental Engineering Faculty Research and Publications

Architecture, engineering, construction and facility management (AEC-FM) projects involve a large number of participants that must exchange information and combine their knowledge for successful completion of a project. Currently, most of the AEC-FM domains store their information about a project in text documents or use XML, relational, or object-oriented formats that make information integration difficult. The AEC-FM industry is not taking advantage of the full potential of the Semantic Web for streamlining sharing, connecting, and combining information from different domains. The Semantic Web is designed to solve the information integration problem by creating a web of structured and connected data …

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Reply To Comment By Fred L. Ogden Et Al. On "Beyond The Scs-Cn Method: A Theoretical Framework For Spatially Lumped Rainfall-Runoff Response", Mark Bartlett, Anthony J. Parolari, Jeffrey Mcdonnell, Amilcare Porporato Jul 2017

Reply To Comment By Fred L. Ogden Et Al. On "Beyond The Scs-Cn Method: A Theoretical Framework For Spatially Lumped Rainfall-Runoff Response", Mark Bartlett, Anthony J. Parolari, Jeffrey Mcdonnell, Amilcare Porporato

Civil and Environmental Engineering Faculty Research and Publications

Though Ogden et al. list several shortcomings of the original SCS-CN method, fit for purpose is a key consideration in hydrological modelling, as shown by the adoption of SCS-CN method in many design standards. The theoretical framework of Bartlett et al. [2016a] reveals a family of semidistributed models, of which the SCS-CN method is just one member. Other members include event-based versions of the Variable Infiltration Capacity (VIC) model and TOPMODEL. This general model allows us to move beyond the limitations of the original SCS-CN method under different rainfall-runoff mechanisms and distributions for soil and rainfall variability. Future research should …

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Development Of Adjustment Factors For Mepdg Pavement Responses Utilizing Finite-Element Analysis, Osman Erman Gungor, Imad L. Al-Qadi, Angeli Gamez, Jaime Hernandez Jul 2017

Development Of Adjustment Factors For Mepdg Pavement Responses Utilizing Finite-Element Analysis, Osman Erman Gungor, Imad L. Al-Qadi, Angeli Gamez, Jaime Hernandez

Civil and Environmental Engineering Faculty Research and Publications

The Mechanistic-empirical pavement design guide (MEPDG) provides theoretically superior methodology, as compared with its predecessor, for the design and analysis of pavement structures. The mechanistic part refers to simulating pavement–tire interaction to calculate critical responses within pavement. The empirical part means prediction of pavement distress propagation over time using transfer functions that link a critical pavement response to a particular pavement distress. The mechanistic part of MEPDG simulates tire–pavement interaction in three steps: subdivision of pavement layers; complex modulus calculation at the middepth of each sublayer, considering velocity and temperature; and running the multilayered elastic theory (MLET) software, …

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Pore Resolved Simulations Of Char Particle Gasification, Greg Hingwah Fong Jul 2017

Pore Resolved Simulations Of Char Particle Gasification, Greg Hingwah Fong

Master's Theses (2009 -)

Coal is a significant source of energy in today’s world and many studies have been conducted in order to better understand and optimize its use. To address greenhouse effects associated with coal combustion, cleaner methods for harnessing its energy are being explored. One such method is gasification, a process which converts coal into syngas, a mixture consisting primarily of H2 and CO. Syngas can be used to generate electricity or to produce hydrocarbons that can be used as fuels. To better understand and optimize the process, simulations can be used to study the gasification of individual porous char particles that …

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An Improved Method Of Arsenic (Iii) Removal By Reverse Osmosis Membrane, Yizhi Hou Jul 2017

An Improved Method Of Arsenic (Iii) Removal By Reverse Osmosis Membrane, Yizhi Hou

Master's Theses (2009 -)

Arsenic is a Group 1 carcinogen as there is abundant research to support that ingestion of arsenic in drinking water and food can lead to liver, lung, kidney, or bladder cancer in humans. The recommend World Health Organization (WHO) arsenic standard in drinking water is 10 µg/L, while the Environmental Protection Agency's (EPA) Maximum Contaminant Level (MCL) of arsenic in drinking water is 10 µg/L. Globally, at least 40 million people face more than 10 µg/L arsenic contamination in their drinking water. As(III) (trivalent state, such as arsenite), and As(V) (pentavalent state, such as arsenates) are the dominant arsenic forms …

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Inclusion Of An Introduction To Infrastructure Course In A Civil And Environmental Engineering Curriculum, Esmaeili Behzad, Philip J. Parker, Steven D. Hart, Brooke K. Mayer, Led Klosky, Michael R. Penn Apr 2017

Inclusion Of An Introduction To Infrastructure Course In A Civil And Environmental Engineering Curriculum, Esmaeili Behzad, Philip J. Parker, Steven D. Hart, Brooke K. Mayer, Led Klosky, Michael R. Penn

Civil and Environmental Engineering Faculty Research and Publications

Civil infrastructure refers to the built environment (sometimes referred to as public works) and consists of roads, bridges, buildings, dams, levees, drinking water treatment facilities, wastewater treatment facilities, power generation and transmission facilities, communications, solid waste facilities, hazardous waste facilities, and other sectors. Although there is a need to train engineers who have a holistic view of infrastructure, there is evidence that civil and environmental engineering (CEE) programs have not fully addressed this increasingly recognized need. One effective approach to address this educational gap is to incorporate a course related to infrastructure into the curriculum for first-year or second-year …

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