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Topic Review
Crystal Mush
A crystal mush is a magmatic body which contains a significant amount of crystals (up to 50% of the volume) suspended in the liquid phase (melt). As the crystal fraction makes up less than half of the volume, there is no rigid large-scale three-dimensional network as in solids. As such, their rheological behavior mirrors that of absolute liquids. Within a single crystal mush, there is grading to a higher solid fraction towards the margins of the pluton while the liquid fraction increases towards the uppermost portions, forming a liquid lens at the top. Furthermore, depending on depth of placement crystal mushes are likely to contain a larger portion of crystals at greater depth in the crust than at shallower depth, as melting occurs from the adiabatic decompression of the magma as it rises, this is particularly the case for mid-oceanic ridges. Seismic investigation offers strong evidence for the existence of crystal mushes rather than fully liquid magmatic bodies. Crystal mushes can have a wide range of chemical and mineralogical compositions, from mafic (SiO2-poor, MgO-rich) to felsic (SiO2-rich, MgO-poor).
  • 874
  • 01 Dec 2022
Topic Review
Microwave-Assisted Pyrolysis of Waste Plastics
Microwave treatment, owning specific interactions between the electric field and the molecules of treated materials, presents potential advantages in the application of plastic pyrolysis. High value-added liquid oil, gas and solid carbon can be obtained from microwave-assisted pyrolysis (MAP) of plastics. Factors that affect the distribution of pyrolysis products of plastics include the properties of plastics, microwave treatment parameters, microwave absorber, co-pyrolysis, catalysts and reactor design. MAP of plastics has broad application prospects, and large-scale pyrolysis processing devices need to be developed. At the same time, the research platform of MAP simulation of plastics still needs to be developed.
  • 874
  • 05 Jun 2023
Topic Review
Ordnance Survey
Ordnance Survey (OS) is the national mapping agency for Great Britain. The agency's name indicates its original military purpose (see ordnance and surveying), which was to map Scotland in the wake of the Jacobite rising of 1745. There was also a more general and nationwide need in light of the potential threat of invasion during the Napoleonic Wars. Since 1 April 2015 Ordnance Survey has operated as Ordnance Survey Ltd, a government-owned company, 100% in public ownership. The Ordnance Survey Board remains accountable to the Secretary of State for Business, Energy and Industrial Strategy. It was also a member of the Public Data Group. Paper maps for walkers represent only 5% of OS' annual revenue. They produce digital map data, online route planning and sharing services and mobile apps, plus many other location-based products for business, government and consumers. Ordnance Survey mapping is usually classified as either "large-scale" (in other words, more detailed) or "small-scale". The Survey's large-scale mapping comprises 1:2,500 maps for urban areas and 1:10,000 more generally. (The latter superseded the 1:10,560 "six inches to the mile" scale in the 1950s.) These large scale maps are typically used in professional land-use contexts and were available as sheets until the 1980s, when they were digitised. Small-scale mapping for leisure use includes the 1:25,000 "Explorer" series, the 1:50,000 "Landranger" series and the 1:250,000 road maps. These are still available in traditional sheet form. Ordnance Survey maps remain in copyright for fifty years after their publication. Some of the Copyright Libraries hold complete or near-complete collections of pre-digital OS mapping.
  • 873
  • 14 Oct 2022
Topic Review
Halemaʻumaʻu Crater
Halemaʻumaʻu Crater (six syllables: HAH-lay-MAH-oo-MAH-oo) is a pit crater located within the much larger summit caldera of Kīlauea in Hawaii Volcanoes National Park. The roughly circular crater was 770 meters (2,530 ft) x 900 m (2,950 ft) prior to collapses that roughly doubled the size of the crater after May 3, 2018. Halemaʻumaʻu is home to Pele, goddess of fire and volcanoes, according to the traditions of Hawaiian religion. Halemaʻumaʻu means "house of the ʻāmaʻu fern". The crater until recently contained an active lava lake. From 2008, when the current vent inside Halemaʻumaʻu crater first erupted, to April 2015, lava was present inside the vent, fluctuating from 20 to 150 meters below the crater rim. On April 24, 2015 molten lava in the vent, known as the Overlook Crater, became directly visible for the first time from the Jaggar Museum overlook at the Hawaiian Volcano Observatory, when the lava rose to an all-time high level since the Overlook Crater first opened. A few days later, on April 29, the lava started spilling over the rim of the Overlook Crater and onto the floor of Halemaʻumaʻu Crater, ultimately adding a layer of lava approximately 30 feet (9 m) thick to the crater floor. For three years from 2015 to 2018 the lava lake level remained close to the rim, with a further minor overflow event in October 2016 and a significant one in April 2018 that covered a majority of the crater floor in new lava. In early May 2018 the lava level in the Overlook Crater dropped over 700 feet and out of sight, resulting in explosions, earthquakes and large clouds of ash and toxic gas, causing closure of the Kīlauea summit area of the national park from May 10 to September 22. While the park visitor center and headquarters have reopened to the public, the crater is currently in a state of collapse that includes substantial portions of Kīlauea Caldera. The Jaggar Museum overlooking the crater remains closed.
  • 872
  • 24 Nov 2022
Topic Review
Microbially Induced Carbonate Precipitation
 Microbially induced carbonate precipitation (MICP) is a promising technology for solidifying sandy soil, ground improvement, repairing concrete cracks, and remediation of polluted land. By solidifying sand into soil capable of growing shrubs, MICP can facilitate peak and neutralization of CO2 emissions because each square meter of shrub can absorb 253.1 grams of CO2 per year.
  • 872
  • 01 Dec 2021
Topic Review
Chemical Rings
The epoxidized group, also known as the oxirane group, can be considered as one of the most crucial rings in chemistry. Due to the high ring strain and the polarization of the C–O bond in this three-membered ring, several reactions can be carried out. One can see such a functional group as a crucial intermediate in fuels, polymers, materials, fine chemistry, etc. 
  • 870
  • 30 Aug 2021
Topic Review
Carbon Capture Storage and/or Utilization
Energy from fossil fuels combustion always generates carbon dioxide, leading to a considerable environmental concern with the values of CO2 produced in the world. The increase in emissions leads to a significant challenge in reducing the quantity of this gas in the atmosphere. To decrease this problem, green and efficient solutions have been extensively studied, such as Carbon Capture Utilization and Storage (CCUS) processes. Broadly recognized as having an enormous potential to meet climate change targets, CCS and CCUS appear as solutions to deliver low carbon heat and power, decarbonize the industry, and, more recently, facilitate the net removal of CO2 from the atmosphere.
  • 870
  • 11 May 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). 
  • 870
  • 03 Aug 2021
Topic Review
Climate Change on Himalayan Yak (Bos grunniens)
Climate change is a global issue, with a wide range of ecosystems being affected by changing climatic conditions including the Himalaya. Yak are exquisitely adapted to the high-altitude conditions of the Himalaya and are thus highly likely to be affected by climate change. 
  • 869
  • 07 Sep 2022
Topic Review
A city Multi-Floor Manufacturing Cluster
Multi-floor manufacturing cluster (MFMC) comprise production and service enterprises of various types of ownership, mainly SMEs, with different production orientations, with the presence of small-scale in-house equipment. This feature of MFMC promotes business competition, allowing for creating collaborative and networked organizations that can happen at some stages of development and can reach a level of a virtual manufacturing network based on Digital Twins models to fulfil customer orders.
  • 867
  • 28 Mar 2022
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