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Topic Review
Antimony as a Critical Raw Material
Antimony is widely acknowledged as a critical raw material of worldwide significance, based on its recognition by many countries. According to current projections, there is an anticipated increase in the demand for antimony in the forthcoming years. An issue of significant concern within the supply chain, which poses a substantial obstacle to sustainable development, is the global unequal allocation of abundant antimony resources. Most nations exhibited a high degree of dependence on a few countries for their net imports of antimony, resulting in a notable disruption and raising concerns regarding the supply chain. 
  • 565
  • 23 Feb 2024
Topic Review
Appications of Natural Clinoptilolites Based on Ion Exchange
There are many natural zeolites, of which a small number, including clinoptilolite, chabazite, mordenite, erionite, ferrierite, and phillipsite offer the greatest promise for industrial applications. Natural clinoptilolites have been the subject for different modifications in order to improve their use potentialities, where the ion exchange property has been a key role for their different applications. Application of ion exchange to modify clinoptilolites, cation selection, mono- and polycationic exchange to create new functional materials for specific applications are key issues.
  • 544
  • 03 Jan 2023
Topic Review
Arsenate Minerals
Arsenate minerals usually refer to the naturally occurring orthoarsenates, possessing the (AsO4)3− anion group and, more rarely, other arsenates with anions like AsO3(OH)2− (also written HAsO42−) (example: pharmacolite Ca(AsO3OH).2H2O) or (very rarely) [AsO2(OH)2]− (example: andyrobertsite). Arsenite minerals are much less common. Both the Dana and the Strunz mineral classifications place the arsenates in with the phosphate minerals. Example arsenate minerals include:
  • 291
  • 25 Nov 2022
Topic Review
Artisanal and Small-Scale Gold Mining
The aim of this work is to explain the concepts of sustainability with respect to small artisanal gold mining. For this, a qualitative approach with a descriptive scope was used, for which the bibliographic review technique was conducted. In this sense, articles, theses, books and institutional documents, and any contribution related to the research topic were taken into consideration. Likewise, this documentation contributed to the delimiting aspects that allowed a contrast between the proposed definitions and small artisanal mining in the Northeast Antioquia region in Colombia. Based on the reviewed sources, different needs were recognized in artisanal small-scale gold mining in Northeast Antioquia that still need action. In conclusion, through the exposition of sustainability theories, three common factors were identified within the various positions that were raised—the environmental, economic, and sociocultural dimensions. 
  • 525
  • 27 Aug 2021
Topic Review
Chromium Deficiency
Chromium deficiency is described as the consequence of an insufficient dietary intake of the mineral chromium. Chromium was first proposed as an essential element for normal glucose metabolism in 1959, and was widely accepted as being such by the 1990s. Cases of deficiency were described in people who received all of their nutrition intravenously for long periods of time. The essentiality of chromium has been challenged. Whereas the authorities in the European Union do not recognize chromium as an essential nutrient, those in the United States do, and identify an adequate intake for adults as between 25 and 45 μg/day, depending on age and sex. Dietary supplements containing chromium are widely available in the United States, with claims for benefits for fasting plasma glucose, hemoglobin A1C and weight loss. Reviews report the changes as modest, and without scientific consensus that the changes have a clinically relevant impact.
  • 415
  • 11 Oct 2022
Topic Review
Clays and the Origin of Life
Clays are able to replicate and drive the evolution of metabolism; they have the catalytic ability to synthesize monomers (amino acids, nucleotides and so on) and polymerize them, resulting in RNA–peptide worlds in which RNA replicates (genes) and, in cooperation with coded peptides, drives the evolution of the cell. 
  • 1.9K
  • 25 Feb 2022
Topic Review
Coal Fly Ash Production, Utilization in India
Coal fly ash (CFA) is one of the most burning issues in the whole world due to its large amount of production in thermal power plants. Every year a million tons (MTs) of CFA are generated globally of which almost half is utilized in various forms, while the remaining half remains unused, leading to various types of pollution.
  • 1.4K
  • 28 Nov 2022
Topic Review
Cracking of Gem Opals
The value of gem opals is compromised by their potential susceptibility to “crazing”, a phenomenon observed either in the form of whitening or cracking.
  • 148
  • 04 Mar 2024
Topic Review
Critical Mineral Raw Materials
Since 2011, the European Commission assesses a 3-year list of Critical Raw Materials (CRMs) for the EU economy within its Raw Materials Initiative. To date, 14 CRMs were identified in 2011, 20 in 2014 and 27 in 2017. These materials are mainly used in energy transition and digital technologies.
  • 439
  • 25 Oct 2022
Topic Review
Diamond-Bearing Ophiolite
Ophiolites are fragments of ancient oceanic crust and upper mantle, which is created at ocean spreading ridges and then emplaced on land. Ophiolite-hosted diamond discovered in ophiolitic peridotite and chromitite is considered to be a new type that has been named an ophiolite-type by Yang et al., in 2011. 
  • 673
  • 22 Nov 2021
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