Air pollution burden of disease over highly populated states in the Middle East

BackgroundRecent epidemiological research has proven that air pollution triggers the risk of morbidity and mortality due to respiratory and cardiovascular-related diseases. More specifically, fine particulate matter with a diameter of <2.5 μm (PM2.5) can penetrate deeply into the lung and bloodstream, causing critical adverse effects on human health.ObjectiveIt is found that there is inadequate published research related to the health impact of ambient air pollution in the Middle East region. Some states are well studied, while others are not. This work aims to evaluate the health impact of long-term exposure to PM2.5 in the nine most populated countries in the Middle East region, with a total population of about 363 million (in 2012).MethodsIn this study, the human health impacts in terms of total mortality and the estimated attributable proportion (AP) due to long-term exposure to ambient PM2.5 were estimated using the World Health Organization method and software (AirQ+).ResultsIn 2012, the annual median PM2.5 concentrations ranged from 34 μg/m3 in Turkey and Syria to 108 μg/m3 in Saudi Arabia. The total estimated mortalities in the nine most populated countries in the Middle East due to long-term exposure to fine particulate matter was about 152,925 (half of which were residents in Egypt). Moreover, the relative risk (RR) was the highest for Saudi Arabia at 1.8031 and the lowest for Turkey and Syria at a value of 1.1553. The highest AP (central value) was 44.5% in Saudi Arabia, while the lowest was 13.4% in Turkey and Syria.ConclusionsThe results indicate a significant impact of air pollution due to long-term exposure to fine particles resulting in early mortality. This urges the collaboration between the governments and different sectors to adopt stringent regulations to control the anthropogenic sources related to traffic and industrial emissions in the Middle East in order to reduce the health burden of air pollution

Quantifying Biomass of Microphytobenthos in sediments of Mangroves in the east coast of Qatar

Mangroves, Avicennia marina, are highly productive coastal ecosystems with capacity to store carbon within plants and in sediments. Micropytobenthos (MPB) in the sediments also fix carbon and play a significant role in carbon burial. However, there is paucity of information on the role of MPB in coastal carbon budget. We quantified the biomass of MPB as an important carbon pool in the mangrove of Al Thakhira, located at the east coast of Qatar. Sediments at different tidal levels namely, supratidal, intertidal, and subtidal were collected and analyzed for grain size, chlorophyll (a), total carbon, and inorganic carbon contents. Results indicated that sand was the dominant species (60%), followed by silt (39%) and clay (1%) at all tidal levels. While the supratidal level had significantly higher silty sand content, silt dominated the intertidal levels. Moreover, chlorophyll (a) was significantly influenced by tidal levels with highest levels in the subtidal level sediments, where mangroves grow extensively. Results also demonstrated that as we move towards the intertidal zone, the total carbon content in sediments gets higher. Finally, chlorophyll (a) and TOC% were positively associated (r=0.643) in all tidal zones. As we move towards the mangrove subtidal growth area, the total carbon content in sediments gets higher. This work recommends that mangrove forests in Qatar be protected by special sanctuaries and law-enforcement to maintain this natural and dynamic blue carbon ecosystem

Technological Advances in Harnessing Energy from Renewable Sources for Water Production

Recently, different technologies such as desalination processes have been utilized to obtain fresh water from natural sources to develop good standards of life, flourish industrial activities, and enhance civilization. Hence, this book chapter aims to cover the fundamental aspects of harnessing energy from the sun or solar cells, covering the history of this topic as well as the new related policies. A discussion of the basics of solar cell devices, performance challenges, and long-term stability will follow. This chapter will also address state-of-the-art membrane-based desalination technologies in generating fresh water from various renewable sources such as solar, wind, wave, and geothermal

Ammonia production plants - a review

Considering the global scientific and industrial effort to utilize ammonia as an alternative to natural gas combustion to run power plants, it is crucial to objectively assess the literature before adjusting or proposing new and advancing techniques in ammonia plants while considering a variety of factors. As a result, this paper assesses the global effort to improve existing ammonia plants and identifies progress by evaluating the currently available dataset to identify knowledge gaps and highlight aspects that have yet to be addressed. Based on the literature reviewed in this study, it was found that the majority of the efforts to advance ammonia plants mainly focus on reducing energy consumption, implementing alternative methods to extract the necessary hydrogen and nitrogen in the process, and changing the cycle arrangement and operating conditions to make the industrial plants more compact. However, regarding carbon reduction in the ammonia production process, it is clear that the effort is less significant when compared to the global scientific and industrial progress in other areas

Simulation of Phase Change Material Absorbers for Passive Cooling of Solar Systems

One of the main challenges that face the reliable use of photovoltaic solar systems in hot arid regions is the prevailing high temperatures during the day. To overcome this issue, Phase Change Materials (PCM) are used for passive cooling providing different options to attain sufficient thermal management solutions for different applications. Passive cooling can be achieved by adjusting a heat sink to the solar PV module. This can be realized by attaching a PCM layer or sensible heat storage to the backside of PV panels. Few studies have reported on simplified modeling and numerical procedures using the apparent heat capacity formulation and volume averaging technique as a robust approach to solving such sophisticated problems with minimal computational efforts, high accuracy, and in a short period of time. However, there is still a need to bridge the large-scale gap between the macroscale within the PCM layer, with a moving melting front, and the length scale of PV modules. Hence, this work focuses on modeling and simulating PCM-Matrix Absorbers (PCM-MA) that consist of fibrous aluminum cellular structure filled with PCM for passive thermal management of PV panels using apparent heat capacity formulation and homogenization based on volume averaging technique. COMSOL Multiphysics FEM software was used for the numerical simulation of the phase change problem by using a Smoothed Heaviside step function to overcome the singularity of PCM challenge that arises with sharp melting temperatures. To validate the proposed model, it has been compared with a benchmark analytical solution for an ice melting problem, i.e., the Stefan problem, in a semi-finite slab, i.e., Neumann’s solution under the same assumptions and boundary conditions. The specific characteristics of phase change and evolution of melting front with time, heat capacity change with the temperature at different times, and with locations along the slab height are presented. As the phase change is modeled to take place over a mushy region, i.e., a narrow temperature interval rather than a sharp melting point, the results show a good coincidence of the heat capacity profile and its peak at different times and locations. The validated model can be used for the optimization of PCM-MA for any specific geographical location and other applications such as the passive cooling of buildings with PCM integrated with the outer envelope. To this end, the results of the simulation in this work are shown to be in agreement with those obtained from the analytical solution

Inflammation resolution in environmental pulmonary health and morbidity

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Simulation of Phase Change Material Absorbers for Passive Cooling of Solar Systems

One of the main challenges that face the reliable use of photovoltaic solar systems in hot arid regions is the prevailing high temperatures during the day. To overcome this issue, Phase Change Materials (PCM) are used for passive cooling providing different options to attain sufficient thermal management solutions for different applications. Passive cooling can be achieved by adjusting a heat sink to the solar PV module. This can be realized by attaching a PCM layer or sensible heat storage to the backside of PV panels. Few studies have reported on simplified modeling and numerical procedures using the apparent heat capacity formulation and volume averaging technique as a robust approach to solving such sophisticated problems with minimal computational efforts, high accuracy, and in a short period of time. However, there is still a need to bridge the large-scale gap between the macroscale within the PCM layer, with a moving melting front, and the length scale of PV modules. Hence, this work focuses on modeling and simulating PCM-Matrix Absorbers (PCM-MA) that consist of fibrous aluminum cellular structure filled with PCM for passive thermal management of PV panels using apparent heat capacity formulation and homogenization based on volume averaging technique. COMSOL Multiphysics FEM software was used for the numerical simulation of the phase change problem by using a Smoothed Heaviside step function to overcome the singularity of PCM challenge that arises with sharp melting temperatures. To validate the proposed model, it has been compared with a benchmark analytical solution for an ice melting problem, i.e., the Stefan problem, in a semi-finite slab, i.e., Neumann’s solution under the same assumptions and boundary conditions. The specific characteristics of phase change and evolution of melting front with time, heat capacity change with the temperature at different times, and with locations along the slab height are presented. As the phase change is modeled to take place over a mushy region, i.e., a narrow temperature interval rather than a sharp melting point, the results show a good coincidence of the heat capacity profile and its peak at different times and locations. The validated model can be used for the optimization of PCM-MA for any specific geographical location and other applications such as the passive cooling of buildings with PCM integrated with the outer envelope. To this end, the results of the simulation in this work are shown to be in agreement with those obtained from the analytical solution