Nov. 2019:Congratulations to Leqi for winning the SecondPlace in 2019 NJIT-GSA!
Explore the Nano World
Jun. 2019: 2019 EPA's National student Design Competition!
Wen's Research Group
Nov. 2019: 2019 Eastern Analytical Symposium!
Phone: (973) 596-5520
Fax: (973) 596-5790
Office Location: Colton Hall 211
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1. Control and mitigate harmful algal blooms by reactive nanobubbles.
Zhang’s group has published three journal articles related to nanobubble technology in Chemosphere, Environmental Engineering Science, and Journal of agricultural and food chemistry. Zhang has patented the NBs generation system (US20190083945A1). This research project was funded by Undergraduate Research and Innovation program (URI) Phase-2 in New Jersey Institute of Technology. The research project has also been funded by United States Environmental Protection Agency (USEPA) 2018 People, Prosperity and the Planet (P3) with $15000.
Coastal (and estuarine) hypoxia is an environmental problem of major and growing global importance – oxygen-depleted conditions (hypoxia and anoxia) result from phytoplankton growth and decay fueled by nitrogen, phosphorus, and sediment inputs from watersheds and have major deleterious impacts on fish and other living resources. Zhang’s group aims to devise a green sustainable process based on reactive nanobubbles (NBs) technology to control and mitigate harmful algal blooms (HABs). NBs may potentially be produced with air, oxygen, ozone or other reactive gases that promote rapid oxidation and decomposition of algae and associated organic contaminants (e.g., cyanotoxin). Although there has been a growing number of NBs applications (e.g., detergent-free cleaning, water aeration, ultra-sound imaging and intracellular drug delivery, and mineral processing), its
potential as a water purification technology remains largely unexplored. The fundamental chemistry of NBs and antimicrobial mechanisms are also not well understood. Accordingly, this project aims to address knowledge gaps to better understand and utilize the unique characteristics of NBs (such as high colloidal stability) and high reactivity (e.g., radical formation) in water dispersion for environmental applications. Zhang’s group aims to devise a ground-breaking and green technology based on reactive NBs to tackle the challenges of harmful algal bloom and cyanotoxin removal. The central hypothesis is that (1) NBs have higher colloidal stability and longer residence time as opposed to regular bulk bubbles or microbubbles that usually float up and escape from water; (2) NBs could produce radicals, especially under external stimuli such as UV irradiation; (3) NBs, due to their ultrasmall sizes, have greater reactivity toward algae and algal pollutants, compared to regular bubbling or purging (e.g., ozonation). Some additional research questions deserve explorations include the algal cell damage kinetics and mechanisms, degradation kinetics and removal efficiency of cyanotoxin, ammonia and other relevant nutrients.
1. AKA Ahmed, Wen Zhang et al. "Generation of nanobubbles by ceramic membrane filters: The dependence of bubble size and zeta potential on surface coating, pore size and injected gas pressure." Chemosphere 203 (2018): 327-335.
2. AKA Ahmed, Wen Zhang, et al. "Colloidal Properties of Air, Oxygen, and Nitrogen Nanobubbles in Water: Effects of Ionic Strength, Natural Organic Matters, and Surfactants." Environmental Engineering Science 35.7 (2018): 720-727.
3. AKA Ahmed, Xiaonan Shi, Wen Zhang et al. "Influences of Air, Oxygen, Nitrogen, and Carbon Dioxide Nanobubbles on Seed Germination and Plant Growth." Journal of agricultural and food chemistry 66.20 (2018): 5117-5124.
Zhang, Wen, Taha Marhaba, and Ahmed Khaled Abdella Ahmed. "System, device, and method to manufacture nanobubbles." U.S. Patent Application No. 16/135,716.