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Topic Review
Ionic and Excited Species
Experimental and theoretical studies of either characterization and reactivity of ionic and excited species with atoms, molecules, and radicals of interest in the chemistry of plasmas and energy production. Single and ionized species with single or multiple charge (H+, He+, H3+, HCO+, H3O+, He22+, CO22+, etc.), excited atoms and molecules (e.g. O(1D), N(2D), H*(2s2S1/2), He*(21,3S0,1), N2*(A3Σu+), etc.) play a crucial role in various important chemical systems such as flames (i.e. chemi-ionizations), natural plasmas (i.e. planetary ionospheres, comet tails and interstellar clouds), and biological environments (e.g. damaged biological tissues via the interaction between ionizing radiation and living cells). Such processes are very interesting from a fundamental point of view in Physical Chemistry and attracted the attention of a wide scientific community, since many applications to important fields: radiation chemistry, plasma physics and chemistry, combustion processes, development of laser sources. In particular, the conversion of waste carbon dioxide via assisted plasma technology gained recently increasing interest due to the possibility of obtaining value-added products, like gaseous or liquid fuels. Such characteristics make this an encouraging strategy for the storage of electrical energy from renewable sources into chemical energy in a circular economy scheme.
  • 1.4K
  • 01 Nov 2020
Topic Review
Climate Fiction
Climate fiction (sometimes shortened cli-fi) is literature that deals with climate change and global warming. Not necessarily speculative in nature, works may take place in the world as we know it or in the near future. University courses on literature and environmental issues may include climate change fiction in their syllabi. This body of literature has been discussed by a variety of publications, including The New York Times , The Guardian , and Dissent magazine, among other international media outlets.
  • 1.4K
  • 14 Oct 2022
Topic Review
Geology
Geology (from grc γῆ 'earth', and -λoγία 'study of, discourse') is a branch of natural science concerned with Earth and other astronomical objects, the features or rocks of which it is composed, and the processes by which they change over time. Modern geology significantly overlaps all other Earth sciences, including hydrology and the atmospheric sciences, and so is treated as one major aspect of integrated Earth system science and planetary science. Geology describes the structure of the Earth on and beneath its surface, and the processes that have shaped that structure. It also provides tools to determine the relative and absolute ages of rocks found in a given location, and also to describe the histories of those rocks. By combining these tools, geologists are able to chronicle the geological history of the Earth as a whole, and also to demonstrate the age of the Earth. Geology provides the primary evidence for plate tectonics, the evolutionary history of life, and the Earth's past climates. Geologists use a wide variety of methods to understand the Earth's structure and evolution, including field work, rock description, geophysical techniques, chemical analysis, physical experiments, and numerical modelling. In practical terms, geology is important for mineral and hydrocarbon exploration and exploitation, evaluating water resources, understanding of natural hazards, the remediation of environmental problems, and providing insights into past climate change. Geology is a major academic discipline, and it is central to geological engineering and plays an important role in geotechnical engineering.
  • 1.4K
  • 27 Nov 2022
Topic Review
Climate of Ancient Rome
The climate of Ancient Rome varied throughout the existence of that civilization. In the first half of the 1st millennium BC the climate of Italy was more humid and cool than now and the presently arid south saw more precipitation. The northern regions were situated in the temperate climate zone, while the rest of Italy was in the subtropics, having a warm and mild climate. During the annual melt of the mountain snow even small rivers would overflow, swamping the terrain (Tuscany and the Pontine Marshes were deemed impassable in antiquity). The existence of Roman civilization (including the Eastern Roman Empire) spanned three climatological periods: Early Subatlantic (900 BC–175 AD), Mid-Subatlantic (175–750) and Late Subatlantic (since 750). The written, archaeological and natural-scientific proxy evidence independently but consistently shows that during the period of the Roman Empire's maximum expansion and final crisis, the climate underwent changes. The Empire's greatest extent under Trajan coincided with the Roman climatic optimum. The climate change occurred at different rates, from apparent near stasis during the early Empire to rapid fluctuations during the late Empire. Still, there is some controversy in the notion of a generally moister period in the eastern Mediterranean in c. 1 AD–600 AD due to conflicting publications.
  • 1.4K
  • 13 Oct 2022
Topic Review
Analysis Method of Heavy Metals in Organic Fertilizers
Heavy metals in organic fertilizers pose a risk to the agricultural ecosystem. The environmental risk of heavy metals depends not only on the total amount but also on the speciation. Hence, more information on heavy metals speciation in organic fertilizers is needed to avoid adverse effect. The speciation information of heavy metals is usually obtained by the single-extraction method and sequential extraction method. Common heavy metals that have received attention include Cu, Zn, Pb, Cd, Cr, Hg and As. 
  • 1.4K
  • 26 Dec 2022
Topic Review
Sunflower Seeds, Oil and Oilcake
Ample amounts of by-products are generated from the oil industry. Among them, sunflower oilcakes have the potential to be used for human consumption, thus achieving the concept of sustainability and circular economy. Sunflower oil contains principally oleic (19.81%) and linoleic (64.35%) acids, which cannot be synthetized by humans and need to be assimilated through a diet. Sunflower seeds are very nutritive (33.85% proteins and 65.42% lipids and 18 mineral elements). Due to the rich content of lipids, they are principally used as a source of vegetable oil. Compared to seeds, sunflower oilcakes are richer in fibers (31.88% and 12.64% for samples in form of pellets and cake, respectively) and proteins (20.15% and 21.60%), with a balanced amino acids profile. The remaining oil (15.77% and 14.16%) is abundant in unsaturated fatty acids (95.59% and 92.12%). The comparison between the three products showed the presence of valuable components that makes them suitable for healthy diets with an adequate intake of nutrients and other bioactive compounds with benefic effects.
  • 1.4K
  • 07 Dec 2021
Topic Review
Organic Matter in Forming Gold-Deposits
Carbonaceous organic matter occurs under various phases and forms, where its fine characterization is mostly restricted to petroleum and coal geology. As a consequence, few studies have integrated the complete link between various forms of organic matter and metals to decipher hydrothermal ore concentrating processes. The study of Dill et al., integrating the concentration of sulfides and oxides with the interaction of silicates and organic matters, is an example of the next step to reach for defining the complex role of organic matter for the formation of orogenic gold deposits.
  • 1.4K
  • 27 Aug 2021
Topic Review
Submarine Canyon
A submarine canyon is a steep-sided valley cut into the seabed of the continental slope, sometimes extending well onto the continental shelf, having nearly vertical walls, and occasionally having canyon wall heights of up to 5 km, from canyon floor to canyon rim, as with the Great Bahama Canyon. Just as above-sea-level canyons serve as channels for the flow of water across land, submarine canyons serve as channels for the flow of turbidity currents across the seafloor. Turbidity currents are flows of dense, sediment laden waters that are supplied by rivers, or generated on the seabed by storms, submarine landslides, earthquakes, and other soil disturbances. Turbidity currents travel down slope at great speed (as much as 70 km/h), eroding the continental slope and finally depositing sediment onto the abyssal plain, where the particles settle out. About 3% of submarine canyons include shelf valleys that have cut transversely across continental shelves, and which begin with their upstream ends in alignment with and sometimes within the mouths of large rivers, such as the Congo River and the Hudson Canyon. About 28.5% of submarine canyons cut back into the edge of the continental shelf, whereas the majority (about 68.5%) of submarine canyons have not managed at all to cut significantly across their continental shelves, having their upstream beginnings or "heads" on the continental slope, below the edge of continental shelves. The formation of submarine canyons is believed to occur as the result of at least two main process: 1) erosion by turbidity current erosion; and 2) slumping and mass wasting of the continental slope. While at first glance, the erosion patterns of submarine canyons may appear to mimic those of river-canyons on land, due to the markedly different erosion processes that have been found to take place underwater at the soil/ water interface, several notably different erosion patterns have been observed in the formation of typical submarine canyons. Many canyons have been found at depths greater than 2 km below sea level. Some may extend seawards across continental shelves for hundreds of kilometres before reaching the abyssal plain. Ancient examples have been found in rocks dating back to the Neoproterozoic. Turbidites are deposited at the downstream mouths or ends of canyons, building an abyssal fan.
  • 1.4K
  • 09 Nov 2022
Topic Review
Climate Change Concerns of Saudi Arabian Farmers
Climate change is a serious threat to the sustainability of global agriculture and food supply that necessitates taking appropriate action for building resilient food production systems and preserving rural economies. In this regard, farmers’ beliefs and concerns about the effects of climate change on agriculture may influence their adoption of adaptation and mitigation practices to address this emerging issue. 
  • 1.4K
  • 29 Nov 2021
Topic Review
DPSIR Assessment on Ecosystem Services
The DPSIR framework (Driver – Pressure – State – Impact – Response) is a useful tool to assess and investigate the cause-effect within an ecosystem to aid better systems - thinking approach for stakeholders, policymakers and governance managers to draft response measures. The DPSIR framework helps to identify and analyse the different effects of human activities over the ecosystem services and human well-being in the different ecosystems such as estuarine, delta, river, coastal, etc. The varied human activities involves mining, construction, fishing, infrastructure development, etc. The DPSIR study shows a holistic view on several interlinked pressures and state changes in the ecosystems, also supporting the development of some potential responses to form systematic, sustainable approaches for mitigating and adapting the impacts caused by human activities. This contribution describes the application of DPSIR framework to study the impacts of sand mining and sand consumption in the Vietnam's Mekong Delta ecosystem services, 
  • 1.4K
  • 25 Nov 2020
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