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The coronavirus (COVID-19) is a threat to public health and caused several social, environmental, and economic problems. During the lockdown in different countries, waste generation has been significantly increased due to the high consumption of packaged food and increase the order of food via online and takeaway. This paper aims to investigate the impact of COVID 19 lockdown on food consumption and the subsequent change in waste generation in Oman. A quantitative research methodology was applied for this study using an online survey during the COVID 19 lockdown. The survey collected information on demographic data, awareness and attitudes toward food purchase behaviour, household food expenditure, and waste generation. The results show that 57.6% of the respondents believed that their food purchasing during the lockdown was increased as compared to before the lockdown. The main reason for increasing the food purchasing was the change in consumers behaviour and cooking more in households during the lockdown. This increase led to the increase in waste generation. One of the main reasons for the increased waste generation during the lockdown was the fact that people have spent more time at home. It was found that food waste and plastic packages were the highest increase (72% and 55%, respectively). These two types of waste are followed by cans and glass bottles with an increase of 68%. Other types of waste such as medical waste, electrical and electronic waste, and paper waste have shown no significant change in waste generation during the lockdown. Overall, this study provides useful information to further promote household food waste prevention behaviour, outlasting the COVID-19 crisis. The results from this study can be used by waste management and municipal utilities on consumption behaviour during emergency situations.

Due to hazardous effluent load of synthetic dyes, the global community is now seeking inclusion of natural products particularly green dyes and pigment in various fields. Current study has been concerned with utilization of eco-friendly tools for isolation of colorants from plant wastes such as coconut coir (Cocos nucifera) for coloration of natural fibers such as wool. Coconut based Tannin was isolated after exposure by microwave treatment for 1-6 min in various media following by optimization of dyeing variables. Excellent yield onto fabric were obtained when coconut coir extract of 1 pH containing 5g/100 mL Glauber salt, was used to dye at 65 oC for 65 min. To develop new shades among mordants used, bio-mordanted wool fabrics exhibited more excellent shades than chemical ones with excellent fastness ratings. It has been concluded that Microwave treatment has excellent potential to isolate natural dye from plant wastes, where the introduction of bio-mordants for shade depth and fastness characteristics has made process more sustainable and viable for natural fibers coloration.

Urban ecosystem resilience is a key concern in the strategy of ecological protection and high-quality development in the Yellow River Basin. This paper uses the principle of range maximization to construct an ecosystem resilience index measurement model from the four dimensions of energy, water resources, environment, and economy and society. The spatio-temporal evolution ecosystem resilience of 99 cities in nine provinces of the Yellow River Basin from 2005 to 2019 was analyzed. The spatial econometric model was used to explore the impact of technological innovation, opening to the outside world and industrial structure on the level of ecosystem resilience, so as to provide guidance for improving the level of ecosystem resilience in the Yellow River Basin. The results are concluded as follows: The level of ecosystem resilience in the Yellow River Basin generally increased first, then decreased, and then increased again. The resilience contribution of the environmental subsystem and the economic and social subsystem is relatively large, while the resilience contribution of the water resource subsystem is relatively small. How to improve the resilience level of the water resource subsystem should be considered as a key issue. Scientific and technological innovation, opening to the outside world and industrial structure had obvious spatial impacts on the resilience of the ecosystem in the Yellow River Basin.

This study investigates the effectiveness of fly ash-based geopolymer concrete was conducted to be used as an alternative material to replace the normal concrete. The concrete mixture was prepared by mixing fly ash, fine aggregate, nano-slag, and SP in Na2SiO3/NaOH solution. The mixture was divided into three different groups, with constant water to fly ash ratio of 0.1, and different alkaline content: 0.4, 0.45, and 0.5 of fly ash rather than two curing techniques (moist and autoclave). Several hardeness properties of concrete like compressive strength, density; and splitting tensile strength were examined after 28 d. The microstructural development of geopolymer concrete was monitored using X-Ray Diffractometer. Based on the results of this investigation, it is recommended to cure the geopolymer concrete by autoclaving rather than the traditional moist technique, especially at lower alkaline dosage. However, the partial addition of nano slag by weight of FA had a positive effect on both curing techniques.