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Full-Text Articles in Engineering

Using A Balloon-Launched Unmanned Glider To Validate Real-Time Wrf Modeling, Travis J. Schuyler, S. M. Iman Gohari, Gary Pundsack, Donald Berchoff, Marcelo I. Guzman Apr 2019

Using A Balloon-Launched Unmanned Glider To Validate Real-Time Wrf Modeling, Travis J. Schuyler, S. M. Iman Gohari, Gary Pundsack, Donald Berchoff, Marcelo I. Guzman

Chemistry Faculty Publications

The use of small unmanned aerial systems (sUAS) for meteorological measurements has expanded significantly in recent years. SUAS are efficient platforms for collecting data with high resolution in both space and time, providing opportunities for enhanced atmospheric sampling. Furthermore, advances in mesoscale weather research and forecasting (WRF) modeling and graphical processing unit (GPU) computing have enabled high resolution weather modeling. In this manuscript, a balloon-launched unmanned glider, complete with a suite of sensors to measure atmospheric temperature, pressure, and relative humidity, is deployed for validation of real-time weather models. This work demonstrates the usefulness of sUAS for validating and improving …


Reduction Of Amine Emissions From An Aqueous Amine Carbon Dioxide Capture System Using Charged Colloidal Gas Aphrons, Xiaobing Li, Jesse G. Thompson, Kunlei Liu Apr 2019

Reduction Of Amine Emissions From An Aqueous Amine Carbon Dioxide Capture System Using Charged Colloidal Gas Aphrons, Xiaobing Li, Jesse G. Thompson, Kunlei Liu

Center for Applied Energy Research Faculty Patents

The present invention includes a system and process to reduce amine mist emissions (or MEA) from carbon capture systems using colloidal gas aphrons (CGA), and includes a method for separating and recovering an amine solvent (e.g., in the form of entrained droplets/mist and/or fine aerosol particles) from a carbon dioxide scrubbed flue gas stream exiting a carbon capture system (e.g., oil-fired power plants, coal-fired power plants, and/or natural gas combined cycle plants).


A Historical Sedimentary Record Of Mercury In A Shallow Eutrophic Lake: Impacts Of Human Activities And Climate Change, Hanxiao Zhang, Shouliang Huo, Kevin M. Yeager, Beidou Xi, Jingtian Zhang, Fengchang Wu Apr 2019

A Historical Sedimentary Record Of Mercury In A Shallow Eutrophic Lake: Impacts Of Human Activities And Climate Change, Hanxiao Zhang, Shouliang Huo, Kevin M. Yeager, Beidou Xi, Jingtian Zhang, Fengchang Wu

Earth and Environmental Sciences Faculty Publications

Mercury and its derivatives are hazardous environmental pollutants and could affect the aquatic ecosystems and human health by biomagnification. Lake sediments can provide important historical information regarding changes in pollution levels and thus trace anthropogenic or natural influences. This research investigates the 100-year history of mercury (Hg) deposition in sediments from Chao Lake, a shallow eutrophic lake in China. The results indicate that the Hg deposition history can be separated into three stages (pre-1960s, 1960s–1980s, and post-1980s) over the last 100 years. Before the 1960s, Hg concentrations in the sediment cores varied little and had no spatial difference. Since the …


Photocatalytic Degradation Of Profenofos And Triazophos Residues In The Chinese Cabbage, Brassica Chinensis, Using Ce-Doped Tio2, Xiangying Liu, You Zhan, Zhongqin Zhang, Lang Pan, Lifeng Hui, Kailin Liu, Xuguo Zhou, Lianyang Bai Mar 2019

Photocatalytic Degradation Of Profenofos And Triazophos Residues In The Chinese Cabbage, Brassica Chinensis, Using Ce-Doped Tio2, Xiangying Liu, You Zhan, Zhongqin Zhang, Lang Pan, Lifeng Hui, Kailin Liu, Xuguo Zhou, Lianyang Bai

Entomology Faculty Publications

Pesticides have revolutionized the modern day of agriculture and substantially reduced crop losses. Synthetic pesticides pose a potential risk to the ecosystem and to the non-target organisms due to their persistency and bioaccumulation in the environment. In recent years, a light-mediated advanced oxidation processes (AOPs) has been adopted to resolve pesticide residue issues in the field. Among the current available semiconductors, titanium dioxide (TiO2) is one of the most promising photocatalysts. In this study, we investigated the photocatalytic degradation of profenofos and triazophos residues in Chinese cabbage, Brassica chinensis, using a Cerium-doped nano semiconductor TiO2 (TiO …


The Effects Of Reactant Concentration And Air Flow Rate In The Consumption Of Dissolved O2 During The Photochemistry Of Aqueous Pyruvic Acid, Alexis J. Eugene, Marcelo I. Guzman Mar 2019

The Effects Of Reactant Concentration And Air Flow Rate In The Consumption Of Dissolved O2 During The Photochemistry Of Aqueous Pyruvic Acid, Alexis J. Eugene, Marcelo I. Guzman

Chemistry Faculty Publications

The sunlight photochemistry of the organic chromophore pyruvic acid (PA) in water generates ketyl and acetyl radicals that contribute to the production and processing of atmospheric aerosols. The photochemical mechanism is highly sensitive to dissolved oxygen content, [O2(aq)], among other environmental conditions. Thus, herein we investigate the photolysis (λ ≥ 305 nm) of 10–200 mM PA at pH 1.0 in water covering the relevant range 0 ≤ [O2(aq)] ≤ 1.3 mM. The rapid consumption of dissolved oxygen by the intermediate photolytic radicals is monitored in real time with a dissolved oxygen electrode. …


Fischer–Tropsch: Product Selectivity–The Fingerprint Of Synthetic Fuels, Wilson D. Shafer, Muthu Kumaran Gnanamani, Uschi M. Graham, Jia Yang, Cornelius M. Masuku, Gary Jacobs, Burtron H. Davis Mar 2019

Fischer–Tropsch: Product Selectivity–The Fingerprint Of Synthetic Fuels, Wilson D. Shafer, Muthu Kumaran Gnanamani, Uschi M. Graham, Jia Yang, Cornelius M. Masuku, Gary Jacobs, Burtron H. Davis

Center for Applied Energy Research Faculty and Staff Publications

The bulk of the products that were synthesized from Fischer–Tropsch synthesis (FTS) is a wide range (C1–C70+) of hydrocarbons, primarily straight-chained paraffins. Additional hydrocarbon products, which can also be a majority, are linear olefins, specifically: 1-olefin, trans-2-olefin, and cis-2-olefin. Minor hydrocarbon products can include isomerized hydrocarbons, predominantly methyl-branched paraffin, cyclic hydrocarbons mainly derived from high-temperature FTS and internal olefins. Combined, these products provide 80–95% of the total products (excluding CO2) generated from syngas. A vast number of different oxygenated species, such as aldehydes, ketones, acids, and alcohols, are also embedded in this product range. …


Effect Of Stoniness On The Hydraulic Properties Of A Soil From An Evaporation Experiment Using The Wind And Inverse Estimation Methods, Nerea Arias, Iñigo Virto, Alberto Enrique, Paloma Bescansa, Riley Walton, Ole O. Wendroth Feb 2019

Effect Of Stoniness On The Hydraulic Properties Of A Soil From An Evaporation Experiment Using The Wind And Inverse Estimation Methods, Nerea Arias, Iñigo Virto, Alberto Enrique, Paloma Bescansa, Riley Walton, Ole O. Wendroth

Plant and Soil Sciences Faculty Publications

Stony soils are distributed all over the world. The study of their characteristics has gained importance lately due to their increasing use as agricultural soils. The effect that rock fragments exert on the soil hydraulic properties is difficult to measure in situ, and is usually derived from the fine earth properties. However, the corrections used so far do not seem accurate for all types of stony soils. Our objective was to assess the adequacy of estimating the hydraulic properties of a stony soil from the fine earth ones by correcting the latter by the volume occupied by rock fragments. To …


Method Of Increasing Mass Transfer Rate Of Acid Gas Scrubbing Solvents, Joseph E. Remias, Cameron A. Lippert, Kunlei Liu Feb 2019

Method Of Increasing Mass Transfer Rate Of Acid Gas Scrubbing Solvents, Joseph E. Remias, Cameron A. Lippert, Kunlei Liu

Center for Applied Energy Research Faculty Patents

A method of increasing the overall mass transfer rate of acid gas scrubbing solids is disclosed. Various catalyst compounds for that purpose are also disclosed.


Effect Of Pt Promotion On The Ni-Catalyzed Deoxygenation Of Tristearin To Fuel-Like Hydrocarbons, Ryan Loe, Kelsey Huff, Morgan Walli, Tonya Morgan, Dali Qian, Robert Pace, Yang Song, Mark Isaacs, Eduardo Santillan-Jimenez, Mark Crocker Feb 2019

Effect Of Pt Promotion On The Ni-Catalyzed Deoxygenation Of Tristearin To Fuel-Like Hydrocarbons, Ryan Loe, Kelsey Huff, Morgan Walli, Tonya Morgan, Dali Qian, Robert Pace, Yang Song, Mark Isaacs, Eduardo Santillan-Jimenez, Mark Crocker

Center for Applied Energy Research Faculty and Staff Publications

Pt represents an effective promoter of supported Ni catalysts in the transformation of tristearin to green diesel via decarbonylation/decarboxylation (deCOx), conversion increasing from 2% over 20% Ni/Al2O3 to 100% over 20% Ni-0.5% Pt/Al2O3 at 260 °C. Catalyst characterization reveals that the superior activity of Ni-Pt relative to Ni-only catalysts is not a result of Ni particle size effects or surface area differences, but rather stems from several other phenomena, including the improved reducibility of NiO when Pt is present. Indeed, the addition of a small amount of Pt to the supported Ni …


Potential Economic Impacts Of Allocating More Land For Bioenergy Biomass Production In Virginia, Thomas O. Ochuodho, Janaki R. R. Alavalapati, Pankaj Lal, Domena A. Agyeman, Bernabas Wolde, Pralhad Burli Feb 2019

Potential Economic Impacts Of Allocating More Land For Bioenergy Biomass Production In Virginia, Thomas O. Ochuodho, Janaki R. R. Alavalapati, Pankaj Lal, Domena A. Agyeman, Bernabas Wolde, Pralhad Burli

Forestry and Natural Resources Faculty Publications

The growing attention to renewable energy and rural development has created greater demand for production of biomass feedstock for bioenergy. However, forest growth rates and the amount of land in most existing forests may not be sufficient to sustainably supply the forest biomass required to support existing forest products industries and the expanding bioenergy industry. Additionally, concerns about agricultural land use competition have dampened expansion of biomass production on agricultural land base. One of the ways to meet the growing forest biomass feedstock demand for bioenergy production is by allocating currently marginal non-forested land for growing bioenergy feedstocks. In Virginia, …


Continuous Catalytic Deoxygenation Of Waste Free Fatty Acid-Based Feeds To Fuel-Like Hydrocarbons Over A Supported Ni-Cu Catalyst, Ryan Loe, Yasmeen Lavoignat, Miranda Maier, Mohanad Abdallah, Tonya Morgan, Dali Qian, Robert Pace, Eduardo Santillan-Jimenez, Mark Crocker Jan 2019

Continuous Catalytic Deoxygenation Of Waste Free Fatty Acid-Based Feeds To Fuel-Like Hydrocarbons Over A Supported Ni-Cu Catalyst, Ryan Loe, Yasmeen Lavoignat, Miranda Maier, Mohanad Abdallah, Tonya Morgan, Dali Qian, Robert Pace, Eduardo Santillan-Jimenez, Mark Crocker

Center for Applied Energy Research Faculty and Staff Publications

While commercial hydrodeoxygenation (HDO) processes convert fats, oils, and grease (FOG) to fuel-like hydrocarbons, alternative processes based on decarboxylation/decarbonylation (deCOx) continue to attract interest. In this contribution, the activity of 20% Ni-5% Cu/Al2O3 in the deCOx of waste free fatty acid (FFA)-based feeds—including brown grease (BG) and an FFA feed obtained by steam stripping a biodiesel feedstock—was investigated, along with the structure-activity relationships responsible for Ni promotion by Cu and the structural evolution of catalysts during use and regeneration. In eight-hour experiments, near quantitative conversion of the aforementioned feeds to diesel-like hydrocarbons was achieved. …


A Total Life Cycle Approach For Developing Predictive Design Methodologies To Optimize Product Performance, Buddhika M. Hapuwatte, Ibrahim S. Jawahir Jan 2019

A Total Life Cycle Approach For Developing Predictive Design Methodologies To Optimize Product Performance, Buddhika M. Hapuwatte, Ibrahim S. Jawahir

Institute for Sustainable Manufacturing Faculty Publications

Sustainable products must be designed by considering how design decisions impact their total life cycle (TLC) sustainability content. Even more so important when designing products to incorporate the technological elements of sustainable manufacturing, the 6Rs (Reduce, Reuse, Recycle, Recover, Redesign and Remanufacture), to achieve Circular Economy (CE). This paper presents the preliminary work of an ongoing research project on developing a novel framework incorporating predictive models with TLC considerations. This unique approach develops and integrates models with associated risks, and optimizes for maximizing the sustainability benefits due to design decisions. Such predictive capability is extremely useful for process planning, where …


Process Sustainability Evaluation For Manufacturing Of A Component With The 6r Application, Ana E. Bonilla Hernández, Tao Lu, Tomas Beno, Claes Fredriksson, Ibrahim S. Jawahir Jan 2019

Process Sustainability Evaluation For Manufacturing Of A Component With The 6r Application, Ana E. Bonilla Hernández, Tao Lu, Tomas Beno, Claes Fredriksson, Ibrahim S. Jawahir

Institute for Sustainable Manufacturing Faculty Publications

Sustainability in manufacturing can be evaluated at product, process and system levels. The 6R methodology for sustainability enhancement in manufacturing processes includes: reduced use of materials, energy, water and other resources; reusing of products/components; recovery and recycling of materials/components; remanufacturing of products; and redesigning of products to utilize recovered materials/resources. Although manufacturing processes can be evaluated by their productivity, quality and cost, process sustainability assessment makes it a complete evaluation. This paper presents a 6R-based evaluation method for sustainable manufacturing in terms of specific metrics within six major metrics clusters: environmental impact, energy consumption, waste management, cost, resource utilization and …


Sustainable Production Through Balancing Trade-Offs Among Three Metrics In Flow Shop Scheduling, Amin Abedini, Wei Li, Fazleena Badurdeen, Ibrahim S. Jawahir Jan 2019

Sustainable Production Through Balancing Trade-Offs Among Three Metrics In Flow Shop Scheduling, Amin Abedini, Wei Li, Fazleena Badurdeen, Ibrahim S. Jawahir

Institute for Sustainable Manufacturing Faculty Publications

In sustainable manufacturing, inconsistencies exist among objectives defined in triple-bottom-lines (TBL) of economy, society, and environment. Analogously, inconsistencies exist in flow shop scheduling among three objectives of minimizing total completion time (TCT), maximum completion time (MCT), and completion time variance (CTV), respectively. For continuous functions, the probability is zero to achieve the objectives at their optimal values, so is it at their worst values. Therefore, with inconsistencies among individual objectives of discrete functions, it is more meaningful and feasible to seek a solution with high probabilities that system performance varies within the …


Designing And Redesigning Products, Processes, And Systems For A Helical Economy, Ryan Bradley, Ibrahim S. Jawahir Jan 2019

Designing And Redesigning Products, Processes, And Systems For A Helical Economy, Ryan Bradley, Ibrahim S. Jawahir

Institute for Sustainable Manufacturing Faculty Publications

The Circular Economy (CE) concept has promised to unlock trillions of dollars in business value while driving a significant reduction in the world’s resource consumption and anthropogenic emissions. However, CE mainly lives in ambiguity in the manufacturing domain because CE does not address the changes needed across all of the fundamental elements of manufacturing: products, processes, and systems. Conceptually, CE is grounded in the concept of closed-loop material flows that fit within ecological limits. This grounding translates into a steady state economy, a result that is not an option for the significant portion of the world living in poverty. Therefore, …