Investigation of factors affecting COVID-19 vaccine acceptance among communities of universities in the United Arab Emirates.

The COVID-19 pandemic affected the lives of people living across the world and the development of vaccines against SARS-CoV-2 is considered to be one of the most promising solutions to contain the COVID-19 pandemic. In several countries, we are witnessing hesitancy toward COVID-19 vaccines, which is a complex phenomenon influenced by a variety of factors. A cross-sectional study was performed to comprehensively investigate the impact of factors like demography, COVID-19 pandemic-induced behavior, and vaccine attitude on COVID-19 vaccine acceptance (VA) among communities of five different universities in the United Arab Emirates (UAE). To investigate the effect of demography and COVID-19 pandemic-induced behavioral factors, Analysis of Variance was perfomed. The effect of COVID-19 vaccine attitudes on COVID-19 VA was examined through partial least squares-structural equations modeling. The results of the study showed no difference among the population in accepting COVID-19 vaccines due to their demographic factors. The effect of pandemic-induced behavioral factors on COVID-19 VA suggested that the people of UAE accepted COVID-19 vaccines irrespective of the movement and travel restrictions imposed due to the pandemic. The results on the effect of vaccine attitudes on COVID-19 VA showed that vaccine benefit attitudes, safety concerns, and trust in health-care professionals (TrHP) were found to be significant factors in VA. Furthermore, TrHP was found to reduce the negative effect of safety concerns related to COVID-19 VA. The findings broadly highlight that COVID-19 VA in the UAE was not hampered by demographic factors and the pandemic-induced behavioral constraints. The study also showed that people with co-morbidities had lower level of COVID-19 VA than people with no co-morbidities. To improve COVID-19 VA, the perceived benefits with COVID-19 vaccine and TrHP must be enhanced and simultaneously safety concerns of the vaccines need to be addressed.

Utilization of the UAE date palm leaf biochar in carbon dioxide capture and sequestration processes.

This paper evaluates the potential use of date palm leaf biochar as a climate change solution through CO2 capture and sequestration. The pyrolysis of date palm leaf was performed at different temperatures 300°, 400°, 500°, and 600 °C. The physicochemical characteristics of the synthesized biochar were examined using Scanning Electron Microscopy (SEM) with Energy Dispersive X-Ray Analysis (EDX), Fourier transforms infrared spectroscopy (FTIR), Thermogravimetric analysis (TGA), and X-ray diffraction analysis (XRD). Direct gas-solid interaction was carried out in an integrated Fluidized Bed Reactor (FBR), connected with a gas analyzer for maximum and effective mixing between the biochar and CO2. LabView program was used as data acquisition for an instantaneous calculation of CO2 adsorption. This study showed that the date palm biochar as porous carbon-based materials has high CO2 adsorption capacity through physisorption and chemisorption progressions. The adsorption results showed a maximum CO2 capture percentage of 0.09 kg CO2/kg, 0.15 kg CO2/kg, 0.20 kg CO2/kg, and 0.25 kg CO2/kg palm biochar synthesized at 300 °C, 400 °C, 500 °C, and 600 °C, respectively. This paper paid attention to the inexpensive technology applied in CO2 sequestration, where fluidization provides well mixing of biochar particles with low operation cost.

CO2 sequestration using accelerated gas-solid carbonation of pre-treated EAF steel-making bag house dust.

Mineral CO2 sequestration is a promising process for the reduction of carbon dioxide emissions to the atmosphere. In this paper, alkaline calcium-rich dust particles collected from bag filters of electric arc furnaces (EAF) for steel making were utilized as a viable raw material for mineral CO2 sequestration. The dust particles were pre-treated through hydration, drying and screening. The pre-treated particles were then subjected to direct gas-solid carbonation reaction in a fluidized-bed reactor. The carbonated products were characterized to determine the overall sequestration capacity and the mineralogical structures. Leaching tests were also performed to measure the extracted minerals from the carbonated dust and evaluate the carbonation process on dust stabilization. The experimental results indicated that CO2 could be sequestered using the pre-treated bag house dust. The maximum sequestration of CO2 was 0.657 kg/kg of dust, based on the total calcium content. The highest degree of carbonation achieved was 42.5% and the carbonation efficiency was 69% at room temperature.

Solidification of cement kiln dust using sulfur binder.

The present study aims to offer a new methodology for consuming two industrial wastes; sulfur, from petroleum and natural gas industries, and cement kiln dust (CKD), from Portland cement industries, in construction industry. Sulfur solidified cement kiln dust material (SSCKDM) was manufactured by mixing molten sulfur, treated sulfur, CKD and sand at a controlled temperature in excess of 120°C. The hot mixture was subsequently cast and shaped into the desired mold and was then allowed to solidify at a specified cooling rate. Solidified materials were immersed for time periods up to 28 days in distilled water at different temperatures of 25 and 60°C, sea water, and acidic and basic universal buffer solutions of pH4 and pH9, respectively. Solidified material performance as function of time and type of aqueous solution exposed to was evaluated in view of compressive strength variations and leachability of metal and heavy metal ions. The results indicated that the solidified articles exhibit homogenous and compact internal microstructure with excellent mechanical properties. However, it showed durability problem upon exposure to aqueous solution environments due to the initial chemical composition of the CKD, whose leached test showed release of relatively high amounts of sulfates and alkali metals. Durability of SSCKDM articles in relation to strength reduction and crack formations control was improved by addition of glass fiber while, the use of anti-leaching agent such as anhydrous sodium sulfide resulted in reduction of leached heavy metals without any measurable decrease in leached amounts of alkali metals and anions from the solidified matrix. Furthermore, based on leachability index method of calculation, potential chemical mobility of metal and heavy metal ions from the solidified matrix was characterized as medium.