Article
Engineering, Environmental
Xiaoping Wang, Jihang Luo, Yunzhu Huang, Jie Mei, Yixia Chen
Summary: The combination of gas phase surface discharge plasma with g-C3N4 photocatalysis shows remarkable efficiency in treating pharmaceutical contaminants, achieving significant removal rates for ibuprofen and tetracycline hydrochloride through degradation and promoting the generation of OH radicals.
ENVIRONMENTAL SCIENCE-WATER RESEARCH & TECHNOLOGY
(2021)
Article
Engineering, Chemical
Shomik Mukhopadhyay, Khushi Patel, Mirko Schoenitz, Edward L. Dreizin
Summary: This study explores the use of electrostatic discharge (ESD) to contactlessly remove particles from contaminated surfaces. An ESD is produced by discharging a capacitor through an air gap. Glass beads of different sizes are used as model powders and placed in cavities of different depths. The study finds that changing the mechanical properties of the substrate holding the powder does not significantly affect the velocities of the ejected particles.
Article
Multidisciplinary Sciences
Rasool Pelalak, Zahra Heidari, Mojtaba Forouzesh, Eslam Ghareshabani, Reza Alizadeh, Azam Marjani, Saeed Shirazian
Summary: The study focused on the degradation of phenazopyridine as an emerging contaminant using catalytic ozonation with novel plasma treated natural limonite under argon atmosphere. Results showed that the synergistic effect between ozone and PTL/Ar nanocatalyst led to the highest efficiency, with the predominant role of hydroxyl radicals and superoxide radicals confirmed. The study also identified main intermediates produced during the oxidation process and demonstrated the superior application of non-thermal plasma for treatment of NL.
SCIENTIFIC REPORTS
(2021)
Article
Chemistry, Multidisciplinary
Xinfeng Yan, Xiaoli Zhou, Ze Li, Yong Qian, Gehao Sheng
Summary: The surface discharge characteristics of the C4F7N/CO2 mixture were studied. It was found that under the same discharge conditions, the optical phenomenon of C4F7N/CO2 discharge along the surface is more pronounced than that of SF6. As the applied voltage or the dielectric constant of the insulator increases, the streamer develops more quickly, the electric field becomes stronger, and the photon flux increases.
APPLIED SCIENCES-BASEL
(2023)
Article
Energy & Fuels
Binhai Fan, Yong Qian, Yiming Zang, Ze Li, Xiaoli Zhou
Summary: This study analyzed the discharge process and characteristics of CF3I gas mixtures through mathematical modeling, showing that while the insulation performance is slightly weaker than SF6, it has the potential to be a substitute for SF6.
Article
Optics
Zhifan Zhang, Peng Lei, Duluo Zuo, Xinbing Wang
Summary: This study investigates the volume scalability of high-density metastable argon atoms using a segmented discharge configuration. By connecting two discharge zones in parallel and charging them with thin wires and peaking capacitors, a uniform and dense plasma was achieved. The results demonstrate the feasibility of using segmented discharge for the development of optically pumped rare gas lasers.
CHINESE OPTICS LETTERS
(2022)
Article
Environmental Sciences
Hekai Jin, Song Lin, Yueyun Yang, Zhixin Liang, Yiqi Chen, Lei Hua, Ying Zhang, Hongtao Jia, Guodong Zhang, Tiecheng Wang
Summary: This study investigates the disintegration of excess sludge by non-thermal discharge plasma coupled with thiosulfate (TSA). The addition of TSA enhances the production of reactive oxygen species, which decompose floc structures and facilitate the transformation of organic compounds, resulting in improved dewaterability of the sludge.
Article
Physics, Fluids & Plasmas
Wenchong Ouyang, Qi Liu, Chengbiao Ding, Zhengwei Wu
Summary: A numerical calculation model was developed to study the interaction of nitrogen plasma with electromagnetic waves. It was found that nitrogen plasma has potential in absorbing electromagnetic waves and stealth effect. Comparisons showed that nitrogen plasma has similar uniformity to helium plasma under the same electron density, indicating that nitrogen can improve its broadband absorption properties without loss of uniformity. Analysis of different radio frequency power and pressure revealed the absorption characteristics of nitrogen plasma.
PHYSICS OF PLASMAS
(2023)
Article
Environmental Sciences
Tengfei Li, Yanhui Fan, Hu Li, Zhiyin Ren, Liqing Kou, Xuetao Guo, Hanzhong Jia, Tiecheng Wang, Lingyan Zhu
Summary: Efficient sludge reduction was achieved by discharge plasma oxidation in this study, with approximately 18.22% sludge disintegration and 27.8% reduction of total suspended solids. The generation of reactive oxygen species played a crucial role in sludge disintegration by destroying flocs and promoting the conversion of organic substances, while concurrent cell lysis released intracellular organics and water into the liquid phase.
SCIENCE OF THE TOTAL ENVIRONMENT
(2021)
Article
Physics, Fluids & Plasmas
Yen Theng Lau, Wee Siong Chiu, Hong Chun Lee, Haw Jiunn Woo, Oi Hoong Chin, Teck Yong Tou
Summary: This article presents the characteristics of a low power 50 Hz argon plasma used for surface treatment of polytetrafluoroethylene (PTFE) film. The experimental results show that under specific conditions, the argon glow plasma can improve the surface wettability of PTFE film, which is mainly attributed to the introduction of oxygen-containing functional groups on the treated surface and reduction in fluorine.
PLASMA SCIENCE & TECHNOLOGY
(2022)
Article
Engineering, Chemical
Tengfei Li, Yuxuan Zhang, Zhiyin Ren, Xiwen Cheng, Hu Li, Ying Zhang, Guangzhou Qu, Tiecheng Wang, Lingyan Zhu
Summary: Heavy metals in active sludge can be released into the liquid phase under discharge plasma treatment, reducing the oxidizable fractions and contamination degree. Plasma oxidation decreased leaching contents of Cr but increased Pb, Zn, Ni, and Cd contents, all of which remained below the limit values.
SEPARATION AND PURIFICATION TECHNOLOGY
(2021)
Article
Cell Biology
Ara Jo, Jin Hee Bae, Yu Jeong Yoon, Tae Hun Chung, Eun-Woo Lee, Young-Ho Kim, Hea Min Joh, Jin Woong Chung
Summary: This study reveals that plasma-activated medium (PAM) promotes cell death in human lung cancer cells through the induction of ferroptosis. PAM increases intracellular and lipid ROS, leading to mitochondrial dysfunction, which can be protected by ROS scavengers and ferroptosis inhibitors.
CELL DEATH & DISEASE
(2022)
Article
Engineering, Electrical & Electronic
Kaiyue Wu, Jingnan Liu, Jiacun Wu, Mo Chen, Junxia Ran, Xuexia Pang, Pengying Jia, Xuechen Li, Chenhua Ren
Summary: This article reports a double-mode argon planar plume, which operates in the streamer mode and transits to the filamentary mode. Discharge characteristics and plasma parameters are compared for the two modes, showing that the streamer mode and the filamentary mode correspond to pulsed and humped discharges respectively. Fast photography reveals that the streamer-mode plume is composed of stochastically branching streamers, while the filamentary-mode plume results from a series of moving filaments similar to those in barrier discharge. The filamentary mode has lower excited electron temperature and vibrational temperature, whereas higher electron density and gas temperature, and it achieves better hydrophilicity of polyethylene terephthalate surface.
Article
Chemistry, Physical
Yen Theng Lau, Oi Hoong Chin, Hong Chun Lee, Wee Siong Chiu, Haw Jiunn Woo
Summary: The study used low power low frequency argon plasma to treat the surface of polystyrene films and found that treatment for 3 minutes under specific conditions significantly improved hydrophilicity and stabilized at a certain water contact angle value. Oxygen was observed to be the main functional group added to the surface, possibly sourced from residual water vapor.
APPLIED SURFACE SCIENCE
(2022)
Article
Physics, Applied
A. A. Talab, Amr M. N. Abido, M. I. Ismail
Summary: The main purpose of this study is to enhance the material properties using a low-cost DC plasma discharge. The best operating conditions of the plasma were obtained by using low-pressure argon gas. Tantalum material was chosen for treatment, and the results showed that the surface treatment of the sample caused cleaning and increased hardness under these low conditions.
INTERNATIONAL JOURNAL OF MODERN PHYSICS B
(2022)
Article
Engineering, Environmental
Charlie J. Liu, Timothy J. Strathmann, Christopher Bellona
Summary: The widespread use of PFASs has led to water contamination globally. High-pressure membranes like NF and RO are effective barriers to PFASs, with NF showing higher rejection rates for PFAAs and lower rejection rates in AFFF-impacted groundwater matrices. Operating conditions did not significantly impact the rejection of PFASs, except for shorter chain PFSAs, where rejection increased with flux. Structure-activity analysis showed some correlation between rejection rates and compound molecular weight, with adsorptive losses of PFAAs observed in membrane elements and systems. Despite this, NF consistently maintained rejection rates > 98% over 13 days.
Editorial Material
Engineering, Civil
Kerry J. Howe, Brent Alspach, Christopher Bellona, Julie Minton, George Tchobanoglous
Summary: In 2020, AWWA Water Science published a topical collection on potable reuse to address issues raised by the increasing demand for water reuse. The collection covers topics such as source water management, pathogen detection and treatment, communications and outreach, and socioeconomics of potable reuse. The guest editors of the collection discussed lessons learned and future challenges for potable reuse regulation and research, highlighting the need for additional research to ensure its safety and reliability as a water supply.
JOURNAL AMERICAN WATER WORKS ASSOCIATION
(2021)
Review
Biotechnology & Applied Microbiology
Sajjad Al-Amshawee, Mohd Yusri Bin Mohd Yunus, Joan G. Lynam, Woo Hyoung Lee, Fei Dai, Ihsan Habib Dakhil
Summary: The roughness and wettability of biofilm carriers play a crucial role in microbial attachment and biofilm stability. Rough and wetted surfaces are essential for the initial adhesion of bacterial communities and provide robust protection from detachment. Insufficient roughness or mismatched wettability with biomass can significantly destabilize the overall biofilm system performance.
ENVIRONMENTAL TECHNOLOGY & INNOVATION
(2021)
Article
Engineering, Mechanical
Andrew M. Bluestein, Douglas Bohl
Summary: Turbulent particle-laden flows were studied in a deep cavity at Reynolds numbers of 11,500 and 115,000, with particle loadings of 0%, 1%, 3%, and 5%. The results showed changes in the locations of recirculation regions within the cavity due to particle loading, with nominal impact on mean velocities. Turbulence modulation was found to be sensitive to Reynolds number and location within the flow field, primarily influenced by differences in the location of flow structures.
JOURNAL OF FLUIDS ENGINEERING-TRANSACTIONS OF THE ASME
(2021)
Article
Thermodynamics
Rayon Venters, Brian T. Helenbrook, Goodarz Ahmadi, Douglas Bohl, Andrew Bluestein
Summary: In this study, turbulent flow in a square duct with a sharp 90 degrees elbow was numerically investigated using DNS and compared to experimental and RANS data. Validation of the flow at a Reynolds number of 11,500 showed good agreement between DNS and experimental results upstream of the bend, but significant differences downstream. Additional flow quantities such as secondary flow structures and Eulerian time scales were also evaluated, showing differences between RANS and DNS results.
INTERNATIONAL JOURNAL OF HEAT AND FLUID FLOW
(2021)
Article
Environmental Sciences
Autumn Osgood, Evie S. Brahmstedt, Matthew J. S. Windle, Thomas M. Holsen, Michael R. Twiss
Summary: This study found that mercury levels in fish from riparian wetlands in the Upper St. Lawrence River were significantly higher than those from non-wetland habitats, indicating that riparian wetlands pose a risk as a source of mercury to fish. This has important implications for both wildlife preservation and fish consumption advisories for public health concerns.
Article
Engineering, Mechanical
Colin Stutz, John Hrynuk, Douglas Bohl
Summary: A novel gust generator was developed to study the interaction of wings with vertical gusts, and force and flow field data for three airfoils were collected under different gust magnitudes, revealing that a new model can more accurately predict lift during gust interactions.
EXPERIMENTS IN FLUIDS
(2022)
Article
Engineering, Chemical
Mikhail Vasilev, Patrick Conlon, Douglas Bohl, Selma Mededovic Thagard
Summary: This study investigates the effects of discharge frequency on the degradation of organic compounds in a gas-liquid plasma reactor. It is found that the discharge frequency controls the compound degradation via multiple mechanisms. The results of this study have significant implications for the design of chemical reactors in water treatment applications.
PLASMA CHEMISTRY AND PLASMA PROCESSING
(2022)
Article
Engineering, Environmental
Hooman Vatankhah, Bahareh Tajdini, Reid P. Milstead, Erica Clevenger, Conner Murray, Detlef Knappe, Christina K. Remucal, Christopher Bellona
Summary: This study investigates the use of ozone and biologically active filtration as standalone and combined pretreatments to enhance the removal of perfluoroalkyl acids in wastewater effluent. It is found that both processes significantly improve the performance of granular activated carbon for PFAA removal. The combination of ozone and biologically active filtration outperforms the standalone processes, indicating its potential for effective PFAA removal.
Article
Mechanics
Douglas G. Bohl, M. M. Koochesfahani
Summary: The dynamics of axial flow is investigated in concentrated line vortices after being cut by a thin wall. The flow field is quantified in terms of axial velocity using one-component molecular tagging velocimetry and simultaneous measurements of spanwise vorticity and axial velocity using stereoscopic molecular tagging velocimetry. Results show that the initially 2-D vortices quickly change to highly distorted regions of vorticity near the cutting wall as the axial flow develops downstream. Small amplitude area-varying waves associated with local changes in vortex axial velocity and peak vorticity are found to propagate away from the wall along the vortex core.
JOURNAL OF FLUID MECHANICS
(2023)
Article
Environmental Sciences
Vincent Hammer, Johan Vanneste, David C. Vuono, Francisco D. Alejo-Zapata, Henry G. Polanco-Cornejo, Julia Zea, Hector G. Bolanos-Sosa, Carlos A. Zevallos Rojas, Linda A. Figueroa, Christopher Bellona
Summary: Cyanide is widely used in large-scale gold extraction and is replacing mercury in small-scale extraction. Current recovery and oxidation processes are expensive and not widely implemented. This study evaluates cyanide recovery using membranes and shows that pH, temperature, and feed cyanide concentration significantly impact the efficiency of the process. Techno-economic analysis shows that membrane contactors are cost-effective for cyanide recovery on both large and small scales.
Article
Engineering, Aerospace
Colin M. Stutz, John T. Hrynuk, Douglas G. Bohl
Summary: This study investigates the effects of different gusts on small Uncrewed Air Systems, finding that the induced negative effective angle of attack from vertical motion has a significant impact on countering the gust, highlighting the need to account for this factor in future gust studies.
AEROSPACE SCIENCE AND TECHNOLOGY
(2023)
Article
Engineering, Environmental
Mikhail Vasilev, Jaymes Suiter, Douglas Bohl, Selma Mededovic Thagard
Summary: This study identifies the important factors in designing and operating efficient plasma reactors for water treatment, using a simple plasma-liquid system. The results show that the plasma-liquid contact area and liquid flow velocity significantly affect the reactor's performance. The study also reveals different caffeine transport modes and provides a criterion for determining the optimal contact time for pulsed plasma reactor operation based on modeling insights.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Engineering, Environmental
Bahareh Tajdini, Hooman Vatankhah, Conner C. Murray, Alexander Liethen, Christopher Bellona
Summary: The occurrence of perfluoroalkyl acids (PFAAs) in wastewater effluent has led to a greater need for effective sorption-based PFAA treatment methods. This study investigated the impact of ozone (O3)-biologically active filtration (BAF) as pretreatment options for nonselective and selective adsorbents. The results showed that O3-BAF in tandem achieved the highest PFAA removal performance improvement. Additionally, the transformation of hydrophobic effluent organic matter (EfOM) to hydrophilic molecules during O3 and biotransformation of EfOM during BAF were the main mechanisms responsible for improving PFAA removal.
Article
Engineering, Environmental
Charlie J. Liu, Conner C. Murray, R. Eric Marshall, Timothy J. Strathmann, Christopher Bellona
Summary: This study evaluated and compared the adsorption of PFASs in contaminated groundwater using granular activated carbon (GAC) and anion exchange resins (AER). The results showed that AERs adsorbed 6-7 times more PFASs than GAC based on media mass or volume. However, when considering the same flowrate, AERs performed similarly to GAC for PFCAs and better for PFSAs. The study also assessed the operational costs of both treatment methods and found that AER and GAC could have similar costs if the ratio of AER to GAC unit media costs was around 3.5.
ENVIRONMENTAL SCIENCE-WATER RESEARCH & TECHNOLOGY
(2022)