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Topic Review
Phosphate Minerals
Phosphate minerals contain the tetrahedrally coordinated phosphate (PO43−) anion along sometimes with arsenate (AsO43−) and vanadate (VO43−) substitutions. Chlorine (Cl−), fluorine (F−), and hydroxide (OH−) anions that also fit into the crystal structure. The phosphate class of minerals is a large and diverse group, however, only a few species are relatively common.
  • 1.0K
  • 14 Nov 2022
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.
  • 989
  • 03 Jan 2023
Topic Review
Mineralogy and Geochemistry of Ferromanganese Crusts
Late Pleistocene–Holocene rocks from the western part of Cocos-Nazca Spreading Centre (C-NSC) include ferromanganese crusts that elucidate the geochemistry and mineralogy of a deep-sea geological setting. Geochemical, mineralogical and petrological signatures indicate complex formation influenced by mild hydrothermal processes. These crusts consist mostly of mixed birnessite, todorokite-buserite, and Mn-(Fe) vernadite with traces of diagenetic manganates (asbolane), Fe-oxides and oxyhydroxides or hydrothermally associated and relatively pure Mn-oxyhydroxides (manganite). The average Mn/Fe ratio is 2.7, which suggests predominant mixed hydrogenous-early diagenetic crusts with hydrothermal influences. The mean concentrations of three prospective metals (Ni, Cu and Co) are low: 0.17, 0.08 and 0.025 wt %, respectively. The total content of ΣREY is also low, and ranges from 81 to 741 mg/kg (mean 339 mg/kg).
  • 984
  • 27 May 2022
Topic Review
Microorganisms in the Nucleation of Carbonates
Microbially induced carbonate precipitation (MICP) is an important process in the synthesis of carbonate minerals, and thus, it is widely explored as a novel approach with potential for many technological applications. The processes and mechanisms involved in carbonate mineral formation in the presence of microbes are not yet fully understood. This research covers the current knowledge regarding the role of microbial cells and metabolic products (e.g., extracellular polymeric substances, proteins and amino acids) on the adsorption of divalent metals, adsorption of ionic species and as templates for crystal nucleation. Moreover, they can play a role in the mineral precipitation, size, morphology and lattice. By understanding how microbes and their metabolic products promote suitable physicochemical conditions (pH, Mg/Ca ratio and free carbonate ions) to induce carbonate nucleation and precipitation, the manipulation of the final mineral precipitates could be a reality for (geo)biotechnological approaches. The applications and implications of biogenic carbonates in areas such as geology and engineering are presented and discussed in this research, with a major focus on biotechnology.
  • 983
  • 03 Jan 2023
Biography
Orson Anderson
From 1964 to the early 1970s, Orson Anderson led a research program at the Lamont Geological Observatory in the newly-emerging field of “mineral physics”. In collaboration with colleagues Edward Schreiber and Naohiro Soga, Orson exploited the techniques of physical acoustics to study the behavior of the sound velocities of minerals at elevated pressures and temperatures. This research progra
  • 962
  • 27 Sep 2022
Topic Review
Respirable Coal Mine Dust Exposure
Respirable coal mine dust (RCMD) exposure is associated with black lung and silicosis diseases in underground miners. Although only RCMD mass and silica concentrations are regulated, it is possible that particle size, surface area, and other chemical constituents also contribute to its adverse health effects. This review summarizes measurement technologies for RCMD mass concentrations, morphology, size distributions, and chemical compositions, with examples from published efforts where these methods have been applied. Some state-of-the-art technologies presented in this paper have not been certified as intrinsically safe, and caution should be exerted for their use in explosive environments. RCMD mass concentrations are most often obtained by filter sampling followed by gravimetric analysis, but recent requirements for real-time monitoring by continuous personal dust monitors (CPDM) enable quicker exposure risk assessments. Emerging low-cost photometers provide an opportunity for a wider deployment of real-time exposure assessment. Particle size distributions can be determined by microscopy, cascade impactors, aerodynamic spectrometers, optical particle counters, and electrical mobility analyzers, each with unique advantages and limitations. Different filter media are required to collect integrated samples over working shifts for comprehensive chemical analysis. Teflon membrane filters are used for mass by gravimetry, elements by energy dispersive X-ray fluorescence, rare-earth elements by inductively coupled plasma-mass spectrometry and mineralogy by X-ray diffraction. Quartz fiber filters are analyzed for organic, elemental, and brown carbon by thermal/optical methods and non-polar organics by thermal desorption-gas chromatography-mass spectrometry. Polycarbonate-membrane filters are analyzed for morphology and elements by scanning electron microscopy (SEM) with energy dispersive X-ray, and quartz content by Fourier-transform infrared spectroscopy and Raman spectroscopy.
  • 961
  • 07 May 2021
Topic Review
Sulfide Minerals
The sulfide minerals are a class of minerals containing sulfide (S2−) or persulfide (S22−) as the major anion. Some sulfide minerals are economically important as metal ores. The sulfide class also includes the selenides, the tellurides, the arsenides, the antimonides, the bismuthinides, the sulfarsenides and the sulfosalts. Sulfide minerals are inorganic compounds.
  • 931
  • 24 Oct 2022
Topic Review
Oxide Minerals
The oxide mineral class includes those minerals in which the oxide anion (O2−) is bonded to one or more metal alloys. The hydroxide-bearing minerals are typically included in the oxide class. The minerals with complex anion groups such as the silicates, sulfates, carbonates and phosphates are classed separately. Simple oxides: Hydroxide subgroup:
  • 925
  • 08 Nov 2022
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.
  • 924
  • 25 Oct 2022
Topic Review
Sulfate Minerals
The sulfate minerals are a class of minerals that include the sulfate ion (SO42−) within their structure. The sulfate minerals occur commonly in primary evaporite depositional environments, as gangue minerals in hydrothermal veins and as secondary minerals in the oxidizing zone of sulfide mineral deposits. The chromate and manganate minerals have a similar structure and are often included with the sulfates in mineral classification systems. Sulfate minerals include:
  • 911
  • 06 Oct 2022
Topic Review
Illite-Age-Analysis
The Illite-Age-Analysis (IAA) method was first proposed by Pevear (1992, 1999)for the catalytic dating of sedimentary basins. After van der Pluijm et al. (2001) discovered a new application for defining the age of fault-thrust development with the IAA method, it has been applied to the shallow faults of various tectonic environments by a number of researchers for the past 20 years, and has played a decisive role in the study of tectonic evolution and understanding of seismic phenomena. In particular, the development of the WILDFIRE© program by Reynolds (1994)has made great strides in the quantitative analysis of illite polytype by simulating the 1M/1Mdpolytype patterns.
  • 873
  • 11 Nov 2021
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. 
  • 843
  • 27 Aug 2021
Topic Review
Evaluation Index System for Mine Ventilation System
The mine ventilation system is an indispensable component to improve coal mining efficiency and ensure the safety production. Only by clearly grasping the comprehensive evaluation quality of ventilation system can effective countermeasures be formulated. This paper establishes an evaluation index system for mine ventilation system by combining qualitative survey with quantitative research. Specifically, the primary indicators are screened through R-type clustering and coefficient of variation method. The weight of each index is determined by the entropy weight method. Moreover, the TOPSIS method are used to evaluate the quality of the mine ventilation system. Finally, this evaluation system is used to evaluate the ventilation renovation project in the production mining area of the Sihe mine. The evaluation results verify the effectiveness of the establishment of mine ventilation evaluation index system and evaluation methods.
  • 827
  • 28 Mar 2022
Topic Review
Electrochemistry of Sulfides
One of the main sources of non-ferrous and precious metals is sulfide ores. The study results of the surface redox transformations of minerals, galvanic effect, cathodic oxygen reduction reaction on the surface of sulfides are presented. The electrochemical properties of sulfide minerals are manifested both in the industrial processes of flotation and hydrometallurgy and in the natural geological setting or during the storage of sulfide-containing mining, mineral processing, and metallurgical industry waste.
  • 769
  • 30 Sep 2022
Topic Review
Sustainability Reporting in Extractive Industries
Sustainability reporting is one of the tools that contribute to incorporating sustainable development in the design of extractive operations (i.e., “Design for Sustainability”), and the demand for sustainability reports is increasing due to the increased focus on sustainable development and sustainable financing efforts. The extractive industries are believed to have unique strengths to contribute to achieving the Sustainable Development Goals. Nonetheless, companies are expected to be transparent and accountable not only to investors but to all stakeholders, including communities, suppliers, clients, employees, and governments. Therefore, extractive industries require effective sustainability accounting and reporting to transition and contribute to sustainable development.
  • 761
  • 16 Sep 2021
Topic Review
Grove Mountains CM-Type Chondrites
CM chondrite is the most important carbonaceous chondrite containing abundant Ca, Al-rich inclusions (CAIs) and other interesting objects, which probably experienced early condensation processes in the Solar Nebula environment and later alteration in parent body surroundings. Thus, it is a vital raw material to explore in the formation and evolution of the early Solar System. Grove Mountains (GRV) CM chondrites have been collected from Antarctica by Chinese Antarctic Research Expedition (CARE) for nearly 20 years.
  • 758
  • 30 Dec 2022
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.
  • 706
  • 11 Oct 2022
Topic Review
Potential Alternative Resources for Rare Earth Elements
Seventeen elements in the periodic table including fifteen lanthanides (La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu) and Sc, as well as Y are often collectively referred to as rare earth elements (REE). The depleting REE ores and increasing mining costs are prompting us to consider alternative sources for these valuable metals, particularly from waste streams. Although REE concentrations in most of the alternative resources are lower than current REE ores, some sources including marine sediments, coal ash, and industrial wastes, such as red mud, are emerging as promising with significant concentrations of REE.
  • 701
  • 13 Apr 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:
  • 554
  • 25 Nov 2022
Topic Review
Factors Affecting Economic Benefits of Organic-Rich Shale Conversion
On the basis of the verification of various laboratory simulations and field pilot production, academic and industrial circles have agreed on the technical feasibility of shale-oil exploitation after organic-rich shale in situ conversion. However, the kerogen cracking process is an endothermic reaction that needs to consume a certain amount of energy. In addition, during the heating process, inorganic minerals and water in the shale are heated synchronously and consume a significant amount of heat energy. Meanwhile, due to the long heating time, much of the heat energy of shale is also dissipated into the surrounding rock through heat conduction. In addition to the high heating costs, the required equipment for in situ conversion is more expensive. Therefore, many experts and companies are concerned about the economic feasibility of in situ conversion. The economic feasibility of oil shale in situ conversion depends on whether the energy consumption ratio (value of produced oil and gas products/(heating energy consumption cost + engineering costs)) is higher than 1. Only when the value of the produced petroleum products is significantly greater than the cost of heating energy consumption can it be expected to realize economic benefits through large-scale commercial development, the dilution of engineering, and other costs. Therefore, improving the ratio of the value of oil and gas products to the cost of heating energy consumption is very important.
  • 533
  • 16 Jun 2023
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