Abstract: The safe ocean disposal of contaminated dredged sediments requires robust, ecologically relevant assessment protocols to evaluate risks to marine ecosystems and human health accurately. This presentation synthesises findings from two complementary studies commissioned by the Hong Kong government. The first study, for the Environmental Protection Department, developed and applied a practical, multi-trophic level bioassay battery for screening sediment toxicity. Tests were conducted on sediment elutriates using a suite of marine organisms: the bacteria Photobacterium phosphoreum (Microtox) and Escherichia coli (Toxi-Chromotest); the microalgae Skeletonema costatum and Dunaliella tertiolecta; the juvenile shrimp Metapenaeus ensis; and the juvenile fish Trachinotus blochii. Solid-phase testing was also performed with the Microtox assay. The second study, for the Civil Engineering and Development Department, investigated the bioaccumulation of contaminants in pelagic fish, benthic organisms, and sensitive species, including the Indo-Pacific Humpback Dolphin (Sousa chinensis) and humans, during the disposal process. Collectively, the results demonstrate that management decisions must be informed by site-specific biological response data from local and ecologically representative species. This integrated approach is crucial for developing robust disposal guidelines that safeguard marine biodiversity, fisheries resources, and public health.

Biography: Professor Wong is a Foreign Member of the Russian Academy of Sciences and a Member of the European Academy of Sciences and Arts. He served as the Editor-in-Chief of ‘Environmental Geochemistry and Health’ (Springer Nature), from 2002 to 2023. Professor Wong was the Coordinator of Central and North-East Asia of ‘Regionally Based Assessment of PTS’ and a Panel Member of ‘Chemicals Management Issues of Developing Countries and Countries with Economies in Transition’, sponsored by UNEP/GEF, 2001-2003 and 2010-2012. His research areas included ‘Environmental toxicology’, ‘Ecological restoration’, and ‘Resource recovery’. Under Environmental Science, Professor Wong is ranked 6th for 3 years, 7th for 1 year, and 8th for 2 years (career-long) globally according to the World’s Top 2% Scientists (Stanford University, 2020-2025).

Abstract: The speaker will use two examples of industrialized technology inventions to describe how to effectively combine and apply the two different disciplines of chemistry and civil engineering to the research and development of various composite materials, and talk about the stories of commercializing the research products. (1) Use cement as raw material to produce nanoparticles (size <5 nm), and use them to prepare a series of hydrogels with super elasticity, adsorption and water swelling properties, and develop their applications in engineering, electronics, biological materials, environment and construction fields. (2) Low-cost, nanoparticle-stabilized foam that can keep stable for years, which could be used to mix with cement paste to prepare lightweight, high-strength, fire-resistant and thermally insulated foam cement. The product was widely used in fabricated lightweight wall panels for energy-efficient buildings.

Biography: Prof. Guoxing SUN received his Ph.D. degree in civil engineering from The Hongkong University of Science and Technology in 2015, and then worked for Nano and Advanced Materials Institute (NAMI), Hongkong. In 2017, he joined University of Macau, where he developed his career starting from assistant professor to associate professor, and was responsible for the industrialization of the new materials. He has conducted 20+ research grants of more than 4 million USD, and led a research group of more than 50 PhD students and Postdoctoral fellows, some of whom have been full professors in well-recognized universities.

Prof. Sun’s research focuses on polymer nanocomposites and construction materials. He discovered a simple way for mass producing 5 nanometer particles by just using normal cement and ice water, and designed a series of high-performance polymer nanocomposite hydrogels enhanced by these cement-released nanoparticles. In 2024, the research work was personally awarded the First-Class Prize in Technological Invention by Mr. Sam Hou Fai, Chief Executive of the Macao SAR.

Contributed to industrialization, Prof. Sun invented a nanoparticle-stabilized foam, which can be simply mixed with cement slurry to fabricate strong light-weight foam concrete. The nano-foam concrete can be 2-5 times stronger or 40% lighter than the relevant market products. It has been widely used and saved 15-40% of cement usage in various construction projects of 15 cities all around the world, such as the largest land port of China, Zhuhai-Macao Hengqin Port Comprehensive Transportation Hub, and Macau Cross-Sea Bridge.

Prof. Sun was reported by China Central Television (CCTV-1, CCTV-4 and CCTV-13) for several times. He is also the recipient of the China National Excellent Young Scientists Fund (2021), Macau Science and Technology Award (2024 and 2022), Building Science and Technology Award issued by China Building Materials Federation (2018). He published over 150 papers in referred journals with total cited times over 7000, and was recognized as World’s Top 2% Scientists in the past two years.

Abstract: Conventional synthetic packaging materials contribute significantly to environmental pollution and the accumulation of solid waste, intensifying the demand for biodegradable, functional alternatives with intrinsic antimicrobial properties. This study presents a multifunctional chitosan/polyvinyl alcohol (CS/PVA) composite film engineered through dual-role tannic acid (TA) crosslinking and TA-mediated surface functionalization of MgO–TiO₂ photocatalysts, targeting both environmental engineering and food preservation applications. TA establishes extensive hydrogen-bonding and metal–phenolic coordination networks that anchor MgO–TiO₂ nanoparticles within the biopolymer matrix, suppressing particle aggregation while inducing ligand-to-metal charge transfer (LMCT). This interfacial engineering broadens light absorption into the visible region and reduces charge recombination, thereby promoting the generation of reactive oxygen species (ROS: •OH and ¹O₂) under ambient light. The optimized TA-crosslinked CS/PVA/MgO–TiO₂ film achieved a 99% increase in tensile strength, a 21% reduction in water vapor permeability, a 38% improvement in oxygen barrier performance, and a 5.5-fold increase in antioxidant activity relative to the pristine CS/PVA film. Visible-light-activated ROS production imparted pronounced antibacterial efficacy, achieving 5.8- and 5.9-log CFU mL⁻¹ reductions against Escherichia coli and Staphylococcus aureus, respectively. Application trials on bananas demonstrated effective delay of surface browning, reduced weight loss, and extended shelf life of 10 days under ambient storage conditions. This work highlights polyphenol–metal coordination as a viable strategy for constructing light-responsive active packaging with integrated photocatalytic, antimicrobial, and barrier functionalities, offering a sustainable pathway toward cleaner production and circular-economy-aligned material design.

Biography: Professor Yao-Tung Lin is a globally recognized expert in environmental engineering, with over three decades of academic and professional experience spanning carbon sequestration, high-value material innovation from agricultural and fishery waste, and advanced synchrotron-based characterization. As a principal investigator and lead scientist, Professor Lin has pioneered novel methods to transform waste into multifunctional materials with antimicrobial, antioxidant, and environmental applications. His research integrates nanotechnology, photocatalysis, and AI-driven material sensing, with special emphasis on chromatic pH-responsive indicators for wound diagnostics and food freshness. In his leadership role, Professor Lin serves as Director of the Taiwan Science and Technology Office for Net-Zero Emission under the Executive Yuan. He is responsible for developing strategies, formulating R&D budgets, and steering technological innovation to meet Taiwan’s 2050 Net-Zero goals. He is also renowned for pioneering work using synchrotron X-ray imaging to visualize the 3D inactivation process of bacteria and intracellular stress responses under environmental stimuli. Professor Lin’s integrative leadership connects science, policy, and sustainability toward a circular, carbon-neutral future.