An overview of construction and demolition waste management in Canada: a lifecycle analysis approach to sustainability

The construction and demolition (C&D) waste generated by the Canadian construction industry accounts for 27 % of the total municipal solid waste disposed in landfills. However, it is evident that over 75 % of what the construction industry generates as waste has a residual value, and therefore could be recycled, salvaged and/or reused. The need for comprehensive and integrated waste management mechanisms, technologies, rating systems and policies is widely recognized. Owing to increasing C&D waste volumes, shortage of landfills and long-term adverse environmental, economic and social impacts of the disposed C&D waste, sustainable C&D waste management is becoming increasingly essential to protect public health and natural ecosystems. This paper proposes a conceptual C&D waste management framework to maximise the 3R (reduce, reuse and recycle) and minimise the disposal of construction waste by implementing sustainable and comprehensive strategy throughout the lifecycle of construction projects. In addition, a life cycle based C&D waste sustainability index is developed. This approach can be used to make decisions related to selection of material, sorting, recycle/reuse and treatment or disposal options for C&D waste.     

Energy rating system for climate conscious operation of multi-unit residential buildings

Residential sector accounts for 17% of domestic energy use and 14% of the greenhouse gas emissions in Canada. Improving the energy performance of the Canadian residential building stock is vital in achieving climate action goals. A comprehensive review of popular building energy rating systems noted their lack of life cycle thinking. The scope of the popular rating systems is limited to operational performance, ignoring the condition of the assets. This paper proposes a condition assessment framework for the energy system of existing multi-unit residential buildings (MURB), which combines the concepts of asset rating and operational rating. Indicators were identified to define energy, environmental, economic, and asset performance of MURB. A life cycle assessment was conducted to quantify the overall environmental impacts of energy technologies from point of generation. A fuzzy logic-based approach was used to overcome the challenges due to data uncertainty and impreciseness. A case study was conducted for a residential building at UBC Okanagan, Canada. The weights at indicator level and category level were defined based on stakeholder consultation, while also considering different decision scenarios. A fuzzy rule-based approach was used to combine the different performance categories to obtain an overall condition rating. The results indicate that the performance of the case study building can be rated as “good” under operational, asset, and overall categories. The findings of this research can be used to improve the asset and operational management strategies in existing buildings and can inform the key stakeholders during the operational phase of the buildings.     

Design of ETB receptor agonists: NMR spectroscopic and conformational studies of ET7-21[Leu7, Aib11, Cys(Acm)15]

In a previous report we have shown that the endothelin-B receptor-selectivelinear endothelin peptide, ET-1[Cys (Acm)1,15, Ala3, Leu7, Aib11],folds into an -helical conformation in a methanol-d₃/water co-solvent[Hewage et al. (1998) FEBS Lett., 425, 234–238]. To studythe requirements for the structure–activity relationships,truncated analogues of this peptide were subjected to furtherstudies. Here we report the solution conformation of ET7–21[Leu7,Aib11, Cys(Acm)15], in a methanol-d₃/water co-solvent at pH3.6, by NMR spectroscopic and molecular modelling studies. Furthertruncation of this short peptide results in it displaying pooragonist activity. The modelled structure shows that the peptidefolds into an -helical conformation between residues Lys9–His16,whereas the C-terminus prefers no fixed conformation. This truncatedlinear endothelin analogue is pivotal for designing endothelin-Breceptor agonists.     

Slow sintering in garnet-containing Y and Gd zirconate–aluminate mixtures for thermal barrier coatings

Mixtures of rare-earth zirconates and aluminates containing Y or Y + Gd that form a two-phase garnet–fluorite mixture exhibit much slower sintering than pure fluorite at 1400°C. An equivalent Y-free, Gd-containing composition that forms a perovskite aluminate instead of garnet showed faster densification after the metastable garnet decomposes. At 1500°C, the Y-free sample also showed the fastest initial sintering rate, whereas there was more divergence in the sintering rate for the samples containing Y + Gd. The zirconate–aluminate with equimolar Y + Gd shows the slowest densification at 1500°C and retains ∼25% porosity after 250 h. The results highlight possibilities for designing compliant thermal barrier coatings that can retain significant porosity at 1400°C or higher.     

Cold atmospheric plasma-induced protein modification: Novel nonthermal processing technology to improve protein quality,functionality, and allergenicity reduction

With the constant increase in protein demand globally, it is expedient to develop a strategy to effectively utilize protein, particularly those extracted from plant origin, which has been associated with low digestibility, poor techno-functional properties, and inherent allergenicity. Several thermal modification approaches have been developed to overcome these limitations and showed excellent results. Nevertheless, the excessive unfolding of the protein, aggregation of unfolded proteins, and irregular protein crosslinking have limited its application. Additionally, the increased consumer demand for natural products with no chemical additives has created a bottleneck for chemical-induced protein modification. Therefore, researchers are now directed toward other nonthermal technologies, including high-voltage cold plasma, ultrasound, high-pressure protein, etc., for protein modification. The techno-functional properties, allergenicity, and protein digestibility are greatly influenced by the applied treatment and its process parameters. Nevertheless, the application of these technologies, particularly high-voltage cold plasma, is still in its primary stage. Furthermore, the protein modification mechanism induced by high-voltage cold plasma has not been fully explained. Thus, this review meets the necessity to assemble the recent information on the process parameters and conditions for modifying proteins by high-voltage cold plasma and its impact on protein techno-functional properties, digestibility, and allergenicity.     

Digital water: artificial intelligence and soft computing applications for drinking water quality assessment

Clean Technologies and Environmental Policy - Water quality deterioration in drinking water systems (i.e., system failure) causing serious outbreaks have frequently been happening around the world....