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Due to increasing problems of freshwater availability and wastewater treatment and management, there is a dire need to control water pollution. A major portion of wastewater is produced through dye contamination from textile industries. In this study, efforts were made to evaluate the renewable, environment-friendly, and biomass-based adsorbent for the effective removal of dyes from aqueous solution. Pine sawdust biomass samples were subjected to adsorption under different parametric studies to optimize the adsorption process efficiency. The maximum adsorption efficiency was observed around 50-60 % under different working conditions. This study demonstrates that the non-linear versions of the PSO and IPD kinetic models were better than the linear forms from the perspective of the dye adsorption mechanism. Comparably, the nonlinear fitting of the Freundlich model yielded lower χ² values and higher R² values than the linear fitting. Positive Gibbs free energy values imply that the adsorption is non-spontaneous and thermodynamically unfavorable at the investigated temperatures. The thermodynamic study shows that the adsorption of BBY onto the PSD adsorbent is an exothermic process. [ABSTRACT FROM AUTHOR]

Reliable prediction of precipitation by numerical weather prediction (NWP) models depends on the appropriate representation of cloud microphysical processes and accurate initial conditions of observations of atmospheric variables. Therefore, to retrieve reasonable cloud distributions, a 1-D variational Ice Cloud Microphysics Data Assimilation System (IMDAS) is developed to improve the predictability of NWP models. The general framework of IMDAS includes the Lin ice cloud microphysics scheme as a model operator, a four-stream last microwave radiative transfer model in the atmosphere as an observation operator, and a global minimization method that is known as the shuffled complex evolution. IMDAS assimilates the satellite microwave radiometer data set of the Advanced Microwave Scanning Radiometer for the Earth Observing System (AMSR-E) and retrieves integrated water vapor and integrated cloud liquid water content. This new method successfully introduces heterogeneity into the initial state of the atmosphere, and the modeled microwave brightness temperatures agree well with the observations of the Wakasa Bay Experiment 2003 in Japan. It has significantly improved the performance of the cloud microphysics scheme by the intrusion of heterogeneity into the external global reanalysis data, which resultantly improved atmospheric initial conditions. Index Terms--Cloud microphysics, data assimilation, integrated cloud liquid water content (ICLWC), integrated water vapor (IWV), Lin ice microphysics scheme, remote sensing.

The energy demand of the world is skyrocketing due to the exponential economic growth and population expansion. To meet the energy requirement, the use of fossil fuels is not a good decision, causing environmental pollution such as CO 2 emissions. Therefore, the use of renewable energy sources like biofuels can meet the energy crisis especially for countries facing oil shortages such as Pakistan. This review describes the comparative study of biodiesel synthesis for various edible oils, non-edible oils, and wastes such as waste plastic oil, biomass pyrolysis oil, and tyre pyrolysis oil in terms of their oil content and extraction, cetane number, and energy content. The present study also described the importance of biodiesel synthesis via catalytic transesterification and its implementation in Pakistan. Pakistan is importing an extensive quantity of cooking oil that is used in the food processing industries, and as a result, a huge quantity of waste cooking oil (WCO) is generated. The potential waste oils for biodiesel synthesis are chicken fat, dairy scum, WCO, and tallow oil that can be used as potential substrates of biodiesel. The implementation of a biodiesel program as a replacement of conventional diesel will help to minimize the oil imports and uplift the country's economy. Biodiesel production via homogeneous and heterogeneous catalyzed transesterification is more feasible among all transesterification processes due to a lesser energy requirement and low cost. Therefore, biodiesel synthesis and implementation could minimize the imports of diesel by significantly contributing to the overall Gross Domestic Product (GDP). Although, waste oil can meet the energy needs, more available cultivation land should be used for substrate cultivation. In addition, research is still needed to explore innovative solvents and catalysts so that overall biodiesel production cost can be minimized. This would result in successful biodiesel implementation in Pakistan., Competing Interests: The authors declare no competing financial interest., (© 2021 The Authors. Published by American Chemical Society.)