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Topic Review
Geography and Cartography in Medieval Islam
Medieval Islamic geography and cartography refer to the study of geography and cartography in the Muslim world during the Islamic Golden Age (variously dated between the 8th century and 16th century). Muslim scholars made advances to the mapmaking traditions of earlier cultures, particularly the Hellenistic geographers Ptolemy and Marinus of Tyre,:193 combined with what explorers and merchants learned in their travels across the Old World (Afro-Eurasia). Islamic geography had three major fields: exploration and navigation, physical geography, and cartography and mathematical geography. Islamic geography reached its apex with Muhammad al-Idrisi in the 12th century.
  • 2.2K
  • 26 Oct 2022
Topic Review
Indoor Air Pollution in Developing Nations
Indoor air pollution in developing nations is a significant form of indoor air pollution (IAP) that is little known to those in the developed world. Three billion people in developing countries across the globe rely on biomass, in the form of wood, charcoal, dung, and crop residue, as their domestic cooking fuel. Since much of the cooking is carried out indoors in environments that lack proper ventilation, millions of people, primarily poor women and children face serious health risks. The major sources of indoor air pollution include combustion and building materials. Globally, 4.3 million deaths were attributed to exposure to IAP in developing countries in 2012, almost all in low and middle-income countries. The South East Asian and Western Pacific regions bear most of the burden with 1.69 and 1.62 million deaths, respectively. Almost 600,000 deaths occur in Africa, 200,000 in the Eastern Mediterranean region, 99,000 in Europe and 81,000 in the Americas. The remaining 19,000 deaths occur in high-income countries. Even though the rate of dependence on biomass fuel is declining, this dwindling resource will not keep up with population growth which could ultimately put environments at even greater risk. Over the past several decades, there have been numerous studies investigating the air pollution generated by traditional household solid fuel combustion for space heating, lighting, and cooking in developing countries. It is now well established that, throughout much of the developing world, indoor burning of solid fuels (biomass, coal, etc.) by inefficient, often insufficiently vented, combustion devices results in elevated exposure to household air pollutants. This is due to the poor combustion efficiency of the combustion devices and the elevated nature of the emissions. In addition, they are often released directly into living areas. Smoke from traditional household solid fuel combustion commonly contains a range of incomplete combustion products, including both fine and coarse particulate matter (e.g., PM2.5, PM10), carbon monoxide (CO), nitrogen dioxide (NO2), sulfur dioxide (SO2), and a variety of organic air pollutants (e.g., formaldehyde, 1,3-butadiene, benzene, acetaldehyde, acrolein, phenols, pyrene, benzopyrene, benzo(a)pyrene, dibenzopyrenes, dibenzocarbazoles, and cresols). In a typical solid fuel stove, about 6–20% of the solid fuel is converted into toxic emissions (by mass). The exact quantity and relative composition is determined by factors such as the fuel type and moisture content, stove type and operation influencing the amount. While many pollutants can evolve, most measurements have been focused on breathing-zone exposure levels of particulate matter (PM) and carbon monoxide (CO), which are the main products of incomplete combustion and are considered to pose the greatest health risks. Indoor PM2.5 exposure levels have been consistently reported to be in the range of hundreds to thousands of micrograms per cubic meter (μg/m3). Similarly, CO exposure levels have been measured to be as high as hundreds to greater than 1000 milligrams per cubic meter (mg/m3). A recent study of 163 households in two rural Chinese counties reported geometric mean indoor PM2.5 concentrations of 276 μg/m3 (combinations of different plant materials, including wood, tobacco stems, and corncobs), 327 μg/m3 (wood), 144 μg/m3 (smoky coal), and 96 μg/m3 (smokeless coal) for homes using a variety of different fuel types and stove configurations (e.g., vented, unvented, portable, fire pit, mixed ventilation stove).
  • 2.2K
  • 22 Nov 2022
Topic Review
Jet (Gemstone)
Jet is a type of lignite, the lowest rank of coal, and is a gemstone. Unlike many gemstones, jet is not a mineral, but is rather a mineraloid. It is derived from wood that has changed under extreme pressure. The English noun jet derives from the French word for the same material, jaiet (modern French jais), ultimately referring to the ancient town of Gagae. Jet is either black or dark brown, but may contain pyrite inclusions which are of brassy colour and metallic lustre. The adjective "jet-black", meaning as dark a black as possible, derives from this material.
  • 2.2K
  • 27 Oct 2022
Topic Review
Middle Eastern Philosophy
Middle Eastern philosophy includes the various philosophies of the Middle East regions, including the Fertile Crescent, Iran, and Anatolia. Traditions include Ancient Egyptian philosophy, Babylonian philosophy, Jewish philosophy, Iranian/Persian philosophy, and Islamic philosophy.
  • 2.2K
  • 05 Dec 2022
Topic Review
Platinum Group Minerals
Russia and South Africa are the world’s leading producers of platinum group elements (PGEs). This places them in a unique position regarding the supply of these two key industrial commodities. The purpose of this paper is to provide a comparative high-level overview of aspects of the geological occurrence, mineralogy, and processing by flotation of the platinum group minerals (PGMs) found in each country. A summary of some of the major challenges faced in each country in terms of the concentration of the ores by flotation is presented alongside the opportunities that exist to increase the production of the respective metals. These include the more efficient recovery of minerals such as arsenides and tellurides, the management of siliceous gangue and chromite in the processing of these ores, and, especially in Russia, the development of novel processing routes to recover PGEs from relatively low grade ores occurring in dunites, black shale ores and in vanadium-iron-titanium-sulphide oxide formations.
  • 2.1K
  • 26 Jan 2021
Topic Review
New Guinea Highlands
The New Guinea Highlands, also known as the Central Range or Central Cordillera, is a long chain of mountain ranges on the island of New Guinea, including the island's tallest peak, Puncak Jaya 16,024 ft (4,884 m), the highest mountain in Oceania. The range is home to many intermountain river valleys, many of which support thriving agricultural communities. The highlands run generally east-west the length of the island, which is divided politically between Indonesia in the west and Papua New Guinea in the east.
  • 2.0K
  • 09 Nov 2022
Topic Review
Western European Colonialism and Colonization
File:SierraLeoneHofstra3.1.tiff European colonialism and colonization was the policy or practice of acquiring full or partial political control over other societies and territories, creating a colony, occupying it with settlers, and exploiting it economically. Research suggests, the current conditions of postcolonial countries have roots in colonial actions and policies. For example, colonial policies, such as the type of rule implemented, the nature of investments, and identity of the colonizers, are cited as impacting postcolonial states. Examination of the state-building process, economic development, and cultural norms and mores shows the direct and indirect consequences of colonialism on the postcolonial states.
  • 2.0K
  • 04 Nov 2022
Topic Review
Detecting Lithium Mineralizations from Space
Optical and thermal remote sensing data have been an important tool in geological exploration for certain deposit types. However, the present economic and technological advances demand the adaptation of the remote sensing data and image processing techniques to the exploration of other raw materials like lithium (Li). A review of the application studies and developments in this field was also made. The addressed topics include: (i) achievements made in Li exploration using remote sensing methods; (ii) the main weaknesses of the approaches; (iii) how to overcome these difficulties; and (iv) the expected research perspectives. We expect that the number of studies concerning this topic will increase in the near future and that remote sensing will become an integrated and fundamental tool in Li exploration.
  • 2.0K
  • 30 Oct 2020
Topic Review
Amazon Basin
The Amazon basin is the part of South America drained by the Amazon River and its tributaries. The Amazon drainage basin covers an area of about 6,300,000 km2 (2,400,000 sq mi), or about 35.5 percent that of the South American continent. It is located in the countries of Bolivia, Brazil , Colombia, Ecuador, Guyana, Peru, Suriname and Venezuela. Most of the basin is covered by the Amazon Rainforest, also known as Amazonia. With a 5.5 million km2 (2.1 million sq mi) area of dense tropical forest, this is the largest rainforest in the world.
  • 2.0K
  • 03 Nov 2022
Topic Review
Fossil Fuels Lobby
"Fossil fuels lobby" is a term used to label the paid representatives of large fossil fuel (oil, gas, coal) and electric utilities corporations who attempt to influence governmental policy. So-called Big Oil companies such as ExxonMobil, Royal Dutch Shell, BP, Total S.A., Chevron Corporation, and ConocoPhillips are amongst the largest corporations associated with the fossil fuels lobby. General Electric, Southern Company, First Energy, and the Edison Electric Institute are also among the most influential electric utilities corporations. By sector, "Energy/Nat Resource" comes fifth, behind "Misc Business", "Finance/Insur/RealEst", Health and "Communic/Electronics".
  • 1.9K
  • 27 Oct 2022
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