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Topic Review
ICON Single-Column Mode
The ICON (ICOsahedral Nonhydrostatic) SCM (single-column mode) is a single-column configuration of the ICON modeling framework. The primary purpose of the ICON SCM is to use it as a tool for research, model evaluation and development. Thanks to the simplified geometry of the ICON SCM, various aspects of the ICON model, in particular the model physics, can be studied in a well-controlled environment. Additionally, the ICON SCM has a reduced computational cost and a low data storage demand. The ICON SCM can be utilized for idealized cases—several well-established cases are already included—or for semi-realistic cases based on analyses or model forecasts.
  • 560
  • 05 Aug 2021
Topic Review
Hydrogen Addition
The addition of hydrogen in natural gas degrades over time the materials of transport and storage. This degradation depends on the ratio of hydrogen natural gas. After addition, several criteria need to be assessed: In the following, the hydrogen embrittlement (HE) effect on design, maintenance and surveillance of smooth and damaged gas pipes is presented.
  • 507
  • 05 Aug 2021
Topic Review
Landfills, Waste and Climate Change
Landfills have been considered the most convenient approach for dealing with waste from time immemorial, even though some have led to disasters of catastrophic proportions. Moreover, recent findings by the International Panel on Climate Change (IPCC) suggest that the decomposing fraction of landfill waste that generates greenhouse gases (GHGs) may not be adequately accounted for and could become a critical issue in our effort to restrict atmospheric temperature increases to 1.5 °C above pre-industrial levels. (According to the IPCC, the maximum atmospheric temperature rise is a factor of cumulative net CO2 emissions as well as net non-CO2 radiative forcing.
  • 626
  • 05 Aug 2021
Topic Review
Rockfall
A rockfall is defined as the “detachment, fall, rolling, and bouncing of rock fragments. It may occur singly or in clusters, but there is little dynamic interaction between the most mobile moving fragments, which interact mainly with the substrate (path)".
  • 1.9K
  • 04 Aug 2021
Topic Review
Remediation Solutions for AMDrainage
Acid Mine Drainage (AMD) is a toxic wastewater stream formed when oxygenated water comes into contact with exposed mine rock surfaces containing sulphide minerals. The formation of AMD is most prominent in abandoned mines where water accumulates in mine shafts and pits allowing exposure to sulphide minerals. The resulting AMD is typically characterised by a low pH with high concentrations of heavy metals and dissolved sulphate. When left untreated, AMD streams can cause severe environmental degradation, including the contamination of natural water bodies, destroying aquatic life and toxifying natural habitats. AMD remediation methods can be divided into two main categories, active treatment and passive treatment methods. Active treatment methods are characterised by process inputs such as energy, chemicals, labour and automated control, whereas passive remediation technologies require minimal process inputs and are mostly self-sustaining. Passive treatment methods are typically at source constructions comprising of a combination of naturally occurring geochemical, physical and biological processes.
  • 821
  • 04 Aug 2021
Topic Review
17O in Hydrological Cycle
17O is the one of the naturally occurring stable isotopes of oxygen, and also it has the lowest abundance, 0.038%(). The distribution of isotopes in hydrological systems is controlled by isotope fractionation processes. Oxygen isotopes fractionate through mass-dependent isotopic fractionation, which includes kinetic processes, isotopic exchange reactions, and physicochemical phenomena (diffusion, condensation, and evaporation).
  • 1.5K
  • 03 Aug 2021
Topic Review
Geochemical Modeling Applications
The geochemical computer model is an important innovation that exponentially evolved in the last decades, and that now plays a vital role in several areas of study, ranging from developing new models for surface complexation, reactive transport models, or the generation of thermodynamic data used to simulate or predict solubility reactions. An important application of geochemical modeling involves supporting the explanation or characterization of engineering systems related to waste management, wastewater reuse, evaluation of water quality from a landfill, metal speciation within soils in industrial areas, new technologies or process for waste treatment, and even the evaluation of the potential to use solid wastes in carbon sequestering processes.
  • 993
  • 03 Aug 2021
Topic Review
Recovery of Rare Earth Elements
Rare earth elements (REEs) as defined by the International Union of Pure and Applied Chemistry (IUPAC) include metals characterized by similar properties, namely scandium (Sc), yttrium (Y) and all the lanthanides. The latter correspond to the chemical elements listed in the periodic table of Mendeleev that have an atomic number ranging from 57 for lanthanum (La) to 71 for lutetium (Lu). REEs are often subdivided into “light rare earths elements” (LREEs) and “heavy rare earths elements” (HREEs) according to their atomic numbers. Yttrium is oftentimes associated with HREEs due to chemical similarities, including ionic radii. In some cases, the elements from samarium to terbium are considered as the “middle rare earth elements” (MREEs). 
  • 891
  • 03 Aug 2021
Topic Review
Removal of Pharmaceuticals from Water
It is important to consider and characterize the efficiency of pharmaceutical removal during wastewater and drinking-water treatment processes. Various treatment options have been investigated for the removal/reduction of drugs (e.g., antibiotics, NSAIDs, analgesics) using conventional or biological treatments, such as activated sludge processes or bio-filtration, respectively. The efficiency of these processes ranges from 20–90%.
  • 1.5K
  • 02 Aug 2021
Topic Review
Real Driving Emissions
Air pollution caused by vehicle emissions has raised serious public health concerns. Vehicle emissions generally depend on many factors, such as the nature of the vehicle, driving style, traffic conditions, emission control technologies, and operational conditions. Concerns about the certification cycles used by various regulatory authorities are growing due to the difference in emission during certification procedure and Real Driving Emissions (RDE). Under laboratory conditions, certification tests are performed in a ‘chassis dynamometer’ for light-duty vehicles (LDVs) and an ‘engine dynamometer’ for heavy-duty vehicles (HDVs). As a result, the test drive cycles used to measure the automotive emissions do not correctly reflect the vehicle’s real-world driving pattern. Consequently, the RDE regulation is being phased to reduce the disparity between type approval and vehicle’s real-world emissions. According to this review, different variables such as traffic signals, driving dynamics, congestions, altitude, ambient temperature, and so on have a major influence on actual driving pollution. Aside from that, cold-start and hot-start have been shown to affect on-road pollution. Contrary to common opinion, new technology such as start-stop systems boost automotive emissions rather than decreasing them owing to unfavourable conditions from the point of view of exhaust emissions and exhaust after-treatment systems. In addition, the driving dynamics are not represented in the current laboratory-based test procedures. As a result, it is critical to establish an on-road testing protocol to obtain a true representation of vehicular emissions and reduce emissions to a standard level. The incorporation of RDE clauses into certification procedures would have a positive impact on global air quality. 
  • 977
  • 02 Aug 2021
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