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Future mineral demand
Published in Natalia Yakovleva, Edmund Nickless, Routledge Handbook of the Extractive Industries and Sustainable Development, 2022
The earth’s surface climate is affected by solar insolation, surface albedo and the greenhouse effect – leading to a warmer earth than would otherwise be possible. Solar insolation is determined by the Earth’s position relative to the sun (e.g., Milankovitch Cycles) as well as minute variations in the level of solar activity (e.g., solar flares). The Earth’s surfaces also reflect differing amounts of insolation back into space, a property known as albedo (e.g., forests, ice, oceans, and urban centres). Finally, the dominant reason why the Earth’s surface is warmer than would be predicted is because of insolation, albedo and the greenhouse effect: the concentration of certain gases in our atmosphere that trap heat and lead to a warming (greenhouse) effect; namely water vapour, carbon dioxide, methane and nitrous oxide. The potential for global warming (GWP) is expressed relative to carbon dioxide, typically over a 100-year timeframe, to represent residence times in the atmosphere and the extent of heat trapping. The GWP for carbon dioxide is 1, methane is 25, nitrous oxide is 298 while various fluorocarbon-related gases range from 92 to 14,800 (e.g., DISER, 2020). Although water vapour is a strong contributor to the greenhouse effect, its very short residence time in the atmosphere means it cannot exert a long-term warming effect, plus the fact that it is not being emitted by humans, leading climate scientists to include water vapour as a feedback mechanism in global climate modelling. Conversely, aerosols or fine particulates create a cooling effect in the atmosphere.
The Atmosphere and the Chemistry of Air
Published in Armen S. Casparian, Gergely Sirokman, Ann O. Omollo, Rapid Review of Chemistry for the Life Sciences and Engineering, 2021
Armen S. Casparian, Gergely Sirokman, Ann O. Omollo
Particulates or particulate matter (PM) is best discussed by grouping them into categories organized by particle size (radius) or dimensions to evaluate their toxic effects. Particulates are microscopic solid or liquid matter suspended in the atmosphere. The term “aerosol” discussed earlier commonly refers to a particulate/air mixture, as opposed to PM alone. Sources of PM may be natural or man-made. They have an impact on climate and precipitation as well as human health. Depending on the size and nature of the particle, they can also serve as carries of toxic vapors. Ammonia vapors are a prime example of this piggybacking effect.
Japanese Approach to Validation
Published in James Agalloco, Phil DeSantis, Anthony Grilli, Anthony Pavell, Handbook of Validation in Pharmaceutical Processes, 2021
Satoshi Sugimoto, Mitsuo Mori, Kiyoshi Mochizuki, Keisuke Nishikawa, Takuji Ikeda, Yusuke Matsuda, Hiroaki Nakamura, Yasuhito Ikematsu
1) For measurement of particulates, particle counters that can detect particulates of different sizes are used. 2) Measurement methods of microorganisms for environmental monitoring include active microbial sampling methods, measurement methods for microorganisms on surfaces, and settling plates. Appropriate samplers and measuring methodology should be selected according to the purpose of the monitoring and the items to be monitored. 3) For cultivation of microorganisms, growth promotion testing should be performed on all lots of prepared media. Media and extraction liquids should be sterilized in an appropriate manner. 4) Identification of microorganisms detected in Grade A and B areas to the species level is recommended.
Hydroxy gas enriched diesel fuel investigations on homogenous charge compression ignition engine with change in injector opening pressure
Published in Petroleum Science and Technology, 2022
Nikhil Aniruddha Bhave, Mahendra M. Gupta, Sandeep S. Joshi
Internal combustion (IC) engines are being used in the automobile sector for a long time. IC engines make use of fossil fuels like gasoline and diesel for the production of useful power. However, the combustion of gasoline and diesel in IC engines is responsible for a high amount of environmental pollution and hazards to living beings. Extremely strict norms are being imposed by developed countries all over the world to control environmental pollution (Duan et al. 2021). Despite these norms, the emissions have been drastically increasing. IC engines are responsible for emitting carbon dioxide (CO2), carbon monoxide (CO), hydrocarbon (HC), oxides of nitrogen (NOx), and smoke (Joy et al. 2020). CI engines are robust, durable, and possess high thermal efficiency. But the emissions of NOx and smoke are substantial (Heywood 1988). A study shows that the European passenger car emission regulatory body has failed when it comes to NOx emissions from diesel-fueled vehicles (Hooftman et al. 2018). The NOx emissions fluctuations were also significant when vehicle engine was operated in NEDC cold start condition (Guo et al. 2020). Reducing emissions of NOx and Smoke simultaneously in a CI engine is a difficult task (Li and Ogawa 2011). Various after-treatment devices like diesel particulate filter (DPF), NOx traps, selective catalytic reduction (SCR), etc. are available which reduce emissions. However, looking at the present scenario, it seems to be an obligation to reduce emission in-cylinder itself (Brijesh and Sreedhara 2013).
Negative and positive environmental perspective of COVID-19: air, water, wastewater, forest, and noise quality
Published in Egyptian Journal of Basic and Applied Sciences, 2021
Ranjan K Mohapatra, Pradeep K Das, Khan Sharun, Ruchi Tiwari, Saumya Ranjan Mohapatara, Pranab K. Mohapatra, Ajit Behera, Tamoghna Acharyya, Venkataramana Kandi, Kudrat-E Zahan, Senthilkumar Natesan, Muhammad Bilal, Kuldeep Dhama
Particulate matters (such as dust, tiny parts of metals, microplastics, soil, chemicals, etc.) are formed in the air mainly due to burning fossil fuels, use of automobiles, steel making, etc. Particulate matter (PM) is described in micrometers. The commonly used terms are PM10 (< 10 µm) and PM2.5 (< 2.5 µm). According to the study reported in Hindustan Times [131], Mumbai (third most polluted city) observed a 42% decrease in PM2.5 levels between 23rd March and 13th April, compared to the past four years (during the same period), and 34% reduction in comparison to 2019 (during the same period). It is also reported that the city has a PM2.5 concentration of 28.8 μg/m3 in this lockdown period. Wuhan is the most adulterated city (35.1 μg/m3) followed by Delhi (32.8 μg/m3), the second most polluted city. New York (4.4 μg/m3) had the lowest PM2.5 levels, followed by Los Angeles (5.5 μg/m3) and Madrid (6.4 μg/m3). In addition, the study also suggested that nine out of ten global cities experienced 25–60% reduction in PM2.5 levels from the same period in 2019.
Methods, availability, and applications of PM2.5 exposure estimates derived from ground measurements, satellite, and atmospheric models
Published in Journal of the Air & Waste Management Association, 2019
Minghui Diao, Tracey Holloway, Seohyun Choi, Susan M. O’Neill, Mohammad Z. Al-Hamdan, Aaron Van Donkelaar, Randall V. Martin, Xiaomeng Jin, Arlene M. Fiore, Daven K. Henze, Forrest Lacey, Patrick L. Kinney, Frank Freedman, Narasimhan K. Larkin, Yufei Zou, James T. Kelly, Ambarish Vaidyanathan
Particulate matter (PM) is a well-established health risk factor, with impacts on human morbidity and mortality through cardiovascular (Brook et al. 2010) and respiratory diseases (Dominici et al. 2006; Ni, Chuang, and Zuo 2015; Wu et al. 2018), lung cancer and cardiopulmonary mortality (Hoek et al. 2013; Pope et al. 2002), premature births (Malley et al. 2017) and other types of diseases (Lin et al. 2017; Tian et al. 2017). Particulate matter is a combination of solid particles and liquid droplets that are suspended in the air, and they are typically classified by aerodynamic diameter (EPA 2018a). Of these, health studies have demonstrated that PM2.5 (i.e., particles that are 2.5 µm or smaller in aerodynamic diameter) is of particular concern for public health. PM2.5 also has a lower rate of gravitational settling, so it can travel long distances in the atmosphere and affect regions far from the emission source, if not removed by precipitation (Ouyang et al. 2015). In this study, we focus on PM2.5, although many of the methodological issues relevant to PM2.5 also relate to PM10 and, in some cases, gas-phase pollutants as well.