Search

Drought is a threat to food security and agricultural sustainability in arid and semi-arid countries. Using wasted silica nanoparticles could minimize water scarcity. A controlled study investigated wheat plant physiological and morphological growth under tap-water irrigation (80–100, 60–80, and 40–60% field capacity). The benefits of S1: 0%, S2: 5%, and S3: 10% nanoparticle silica soil additions were studied. Our research reveals that water stress damages the physiological and functional growth of wheat plants. Plant height decreased by 8.9%, grain yield by 5.4%, and biological yield by 19.2%. These effects were observed when plants were irrigated to 40–60% field capacity vs. control. In plants under substantial water stress (40–60% of field capacity), chlorophyll a (8.04 mg g−1), b (1.5 mg g−1), total chlorophyll (9.55 mg g−1), carotenoids (2.44 mg g−1), and relative water content (54%), Electrolyte leakage (59%), total soluble sugar (1.79 mg g−1 fw), and proline (80.3 mol g−1) were highest. Plants cultivated with silica nanoparticles exhibit better morphological and physiological growth than controls. The largest effect came from maximum silica nanoparticle loading. Silica nanoparticles may increase drought-stressed plant growth and production. This study investigates the impact of silica nanoparticles on the development of wheat plants experiencing water stress. Silica nanoparticles are essential for stimulating biochemical defenses against water stress, although research is limited. In stressed wheat plants, silica nanoparticles as a soil supplement increased biological and grain yield. Wheat grown under drought conditions will benefit from this study. [ABSTRACT FROM AUTHOR]

First- and second-generation hydroxyl-terminated dendrimers were prepared starting from a 1,3-diaminopropane core and sulfonimide linkers. A first-generation mesitylene-derived dendrimer was also prepared with the same terminals. The dendrimers were then reacted with Fe3+, Al3+, and UO22+ separately in order to apply the dendrimers for binding these metals, which have important industrial applications and pose environmental problems simultaneously. The prepared dendrimers were also shown to bind Fe3+ selectively from mixtures with Al3+. [ABSTRACT FROM AUTHOR]

Electric arc furnace dust (EAFD) and polyvinyl chloride (PVC) are two hazardous wastes that are accumulated world-wide at an alarming rate. Utilising these two wastes simultaneously towards a sustainable recycling loop can greatly mitigate their environmental impact. Herein, EAFD was studied as a potential emission fixator of evolved gaseous HCl generated from the thermal decomposition of PVC under different operational conditions: EAFD-PVC mass ratio, solid reactants geometry, O2 partial pressure, holding temperature, holding time and heating rate. The highest chlorine fixation percentage was calculated to be 78.9% and was obtained at an EAFD-PVC mass ratio of 1:1 (thin disks geometry), while the rest escaped in the form of HCl/Cl2. No significant variation was observed on the percentage of fixed chlorine when the thermal treatment was performed using different geometries: long cylinder, thin disks, and powder forms with a maximum difference in fixation of only 5.6% between extremities. Increasing O2 partial pressure positively affected the chlorine fixation percentage increasing it from 39.9 to 48.4% at 0 and 21 kPa partial pressures, respectively. Increasing both the holding temperature and holding time under oxidative conditions negatively affected the percentage of fixed chlorine due to oxidation of formed FeCl2 back to Fe2O3. The heating rate did not show any significant effect on the amount of fixed HCl, suggesting that the speed of chlorination reactions can be identical to or faster than the decomposition rate of PVC. Overall, EAFD is believed to be an excellent candidate for capturing HCl contained in PVC upon thermal degradation. [ABSTRACT FROM AUTHOR]

Livestock and chicken manures generated in 2017 in Al-Mafraq governorate (North of Jordan) were estimated to be around 250 × 103 tons and expected to increase in the coming years. Therefore, the accumulation of animal manures will continue to pose a significant threat to public health by direct or indirect exposure. In this work, manures of cow, sheep/goats, and chicken and poultry litter were tested for their chemical composition and thermal characteristics, and then the potential of these manures as valuable renewable energy resources were examined. The proximate and ultimate analyses of these wastes were evaluated along with their heating values. Representative samples of different animal manures, chicken feather, and poultry litter were also subjected to a pyrolysis process. Poultry litter had the highest heating value (19.48 MJ/kg) among the tested samples, followed by chicken feathers (18.95 MJ/kg) and sheep/goat (10.92 MJ/kg). Cow manure had the lowest heat value (8.68 MJ/kg). Based on the elemental analysis, poultry waste had the highest contents of carbon and hydrogen, while cow manure had the lowest. Positive correlations were found between the levels of hydrogen and carbon of the selected wastes and their heat values. Poultry litter had a high nitrogen content and a low C:N ratio, whereas cow manure had the lowest nitrogen content and the highest C:N ratio. Poultry manure and litter had a higher volatile matter and a lower ash content than sheep/goat and cow manures. Chicken manure was the best among the tested samples in terms of bio-oil production (36 wt%) followed by poultry litter and sheep/goat manures, while cow manure was the lowest. Poultry litter was found to be the best source for biogas production. It is anticipated that 48.7 million m3 of biogas can be produced annually from the available animal waste resources in this governorate, and this amount of biogas can be converted into energy of about 10.1 × 106 GJ. This amount of energy can satisfy the energy demand of at least 5% of the population in the Al-Mafraq governorate. In conclusion, the study recommended that converting animal solid manures to energy would be a promising waste management option or strategy to be applied in this governorate as well as in Jordan. [ABSTRACT FROM AUTHOR]