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Topic Review
Late Permian Coals
This study reports the mineralogy and geochemistry of the Late Permian C1 Coal from Bole and Laibin mines in eastern Yunnan, Southwestern China (C1 Coal in Laibin mine is composed of three layers termed B1, B2, and B3). The coals are characterized by medium-high ash yields and very low sulfur contents. Compared with average values of trace element concentrations in hard coals worldwide, the Bole and Laibin coals are enriched in V, Co, Cu, Zn, and Se, which were mainly derived from the sediment-source region of the Kangdian Upland. Major minerals in the coal samples and roof and floor strata include quartz, interstratified berthierine/chamosite (B/C), as well as kaolinite, mixed layer illite/smectite, calcite, pyrite, and anatase. Unlike a pure chamosite, the 7 Å peak of interstratified B/C is sharp and narrow, while the 14 Å peak is broad and weak, or absent in some coal samples. Interstratified B/C was largely precipitated from low-temperature Fe-rich and Mg-rich hydrothermal fluids or, in some cases, is an alteration product of kaolinite. Secondary phases of quartz, calcite, pyrite, kaolinite, chalcopyrite, gypsum, and REE-phosphates in the coal samples are the dominant authigenic minerals formed at syngenetic and early diagenetic stages. Four intra-seam partings in C1 Coal, B1, and B3 layers are identified as tonsteins derived from felsic volcanic ashes. These tonsteins consist mainly of cryptocrystalline kaolinite with graupen and vermicular textures, and minor amounts of high-temperature quartz, zircon, apatite, monazite, and anatase. The floor of the C1 Coal in the Bole mine is a tuffaceous claystone and consists of altered high-Ti basalt volcaniclastics, characterized by high concentrations of Zr, Nb, V, Co, Cu, and Zn, low Al2O3/TiO2 ratio (~4.62), high Ti/Y ratio (~900), enrichment of middle rare earth elements, and positive Eu anomalies.
  • 778
  • 19 Jan 2021
Topic Review
Sierra Espuña Cenozoic Malaguide Basin
The Cenozoic Malaguide Basin from Sierra Espuña (Internal Betic Zone, S Spain) due to the qual-ity of outcropping, areal representation, and continuity in the sedimentation can be considered a key-basin. In the last 30 years, a large number of studies with very different methodological ap-proaches have been done in the area. Models indicate an evolution from passive margin to wedge-top basin from Late Cretaceous to Early Miocene. Sedimentation changes from limestone platforms with scarce terrigenous inputs, during the Paleocene to Early Oligocene, to the deep ba-sin with huge supplies of turbidite sandstones and conglomerates during the Late Oligocene to Early Miocene. The area now appears structured as an antiformal stack with evidence of synsedimentary tectonics.
  • 802
  • 19 Jan 2021
Topic Review
Female Fertility and Environmental Pollution
Terrestrial ecosystems are contaminated by heavy metals and organic chemicals that can be taken up by and accumulate in crop plants, and water tables are heavily contaminated by untreated industrial discharges. As deadly particulates can drift far, poor air quality has become a significant global problem and one that is not exclusive to major industrialized cities. The consequences are a dramatic impairment of our ecosystem and biodiversity and increases in degenerative or man-made diseases. In this respect, it has been demonstrated that environmental pollution impairs fertility in all mammalian species. The worst consequences are observed for females since the number of germ cells present in the ovary is fixed during fetal life, and the cells are not renewable. This means that any pollutant affecting hormonal homeostasis and/or the reproductive apparatus inevitably harms reproductive performance. 
  • 873
  • 18 Jan 2021
Topic Review
Indoor Air Quality Management
The existence of indoor air pollutants—such as ozone, carbon monoxide, carbon dioxide, sulfur dioxide, nitrogen dioxide, particulate matter, and total volatile organic compounds—is evidently a critical issue for human health. Over the past decade, various international agencies have continually refined and updated the quantitative air quality guidelines and standards in order to meet the requirements for indoor air quality management. This entry first provides a systematic review of the existing air quality guidelines and standards implemented by different agencies, which include the Ambient Air Quality Standards (NAAQS); the World Health Organization (WHO); the Occupational Safety and Health Administration (OSHA); the American Conference of Governmental Industrial Hygienists (ACGIH); the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE); the National Institute for Occupational Safety and Health (NIOSH); and the California ambient air quality standards (CAAQS). It then adds to this by providing a state-of-art review of the existing low-cost air quality sensor (LCAQS) technologies, and analyzes the corresponding specifications, such as the typical detection range, measurement tolerance or repeatability, data resolution, response time, supply current, and market price. Finally, it briefly reviews a sequence (array) of field measurement studies, which focuses on the technical measurement characteristics and their data analysis approaches.
  • 1.4K
  • 18 Jan 2021
Topic Review
Stream Ecological Integrity
Streams and rivers provide important services to humans, and therefore, their ecological integrity should be a societal goal. Although ecological integrity encompasses structural and functional integrity, stream bioassessment rarely considers ecosystem functioning. Organic matter decomposition and ecosystem metabolism are prime candidate indicators of stream functional integrity.
  • 623
  • 11 Jan 2021
Topic Review
Social Acceptance of Renewable Energy
Social acceptance of renewable energy is the attitude of the local population of a given territory to accept the presence, installation or expansion of plants, projects and processes for the production of energy from renewable sources (RES) such as geothermal, sun, wind and biomass. It differs from the generally favorable predisposition of a population towards RES in places far from their homes: indeed, social acceptance of local RES can hinder the development of renewable energy projects, even for a population whose general acceptance of RES is relatively high. 
  • 1.4K
  • 08 Jan 2021
Topic Review
Coastal Dune
This work analyzes the evolution of the large shifting dune included in the Corrubedo Natural Park from 1956 until the present day. The analysis was carried out using aerial images, orthophotographs, topographic surveys and LiDAR (Light Detection and Ranging) data. Variations were analyzed in terms of four different aspects: evolution of pathways in each period, changes in the position of the mobile dune front and the degree of vegetation cover, all between 1956 and 2017; and variations in elevation and volume of the dune system between 2001 and 2015. To analyze these aspects, geospatial and geostatistical techniques were employed, which revealed that the dune front had undergone two different phases: one until the 1980s, with a mean seaward advance of 32 m and another one between the 1980 s and 2017, when the front prograded to the continent, with an approximate mean advance of 82 m. Loss of volume, related to the expansion of the mobile dune towards the north, was confirmed in this sector. It is evident that these changes are closely linked to anthropic influence, due to sand extraction until the early 1990s and, more recently, due to an increase in the number of visitors to the Natural Park. The results obtained highlight the need to carry out detailed studies to understand the evolution of this system and to prevent further damage in the future. Moreover, based on these analyses, a strategy to improve coastal and environmental management in the Corrubedo Natural Park could be designed.
  • 821
  • 06 Jan 2021
Topic Review
BIO-Argo Float
BIO-Argo float (chlorophyll a (Chl-a), temperature, and salinity profiles) and remote sensing data (Chl-a, photosynthetic available radiation (PAR), and wind) located south of the Kuroshio current near Shikoku from September 2018 to May 2019 were used to study phytoplankton bloom and their mechanisms of development in open oceans.
  • 731
  • 29 Dec 2020
Topic Review
UAVs to CBRN Threats monitoring
Unmanned aerial vehicles (UAVs) play an increasingly important role in various areas of life, including in terms of protection and security. The possibilities of using the devices were analyzed in terms of weather conditions, construction, and used materials in CBRN (chemical, biological, radiological, nuclear) threat situations. It was found that, thanks to the use of appropriate sensors, cameras, and software of UAVs integrated with a given system, it is possible to obtain information on air quality at a given moment, which is very important for the safety of people and the environment. However, several elements, including the possibility of use in acidification conditions, requires refinement to changing crisis conditions.
  • 1.6K
  • 28 Dec 2020
Topic Review
Vegetables Irrigated with Untreated Wastewater
Vegetables are commonly cultivated with untreated wastewater and consumed by human beings who often ignore their harmful impacts on health. The industrialization and urbanization in developing countries have led to the release of increasing amounts of heavy metals (HM) into the environment. Regular monitoring of metal concentration levels in contaminated soils and edible plants is essential to prevent their excessive build-up in the diet and food chains.
  • 2.2K
  • 25 Dec 2020
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