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Topic Review
MOFs as ODS Catalysts
Catalytic oxidative desulfurization (ODS) of fuel oils is considered one of the most promising non-hydrodesulfurization technologies due to the advantages of mild reaction conditions, low cost and easy removal of aromatic sulfur compounds. Based on this reason, the preparation of highly efficient ODS catalysts has been a hot research topic in this field. Metal-organic frameworks (MOFs) have received much attention due to advantages such as abundant metal centers, high surface areas and varied pore structures, which are composed of secondary building units (SBUs) connected by organic linkers to form crystalline porous materials. Such materials possess both the rigidity of inorganic materials and the flexibility of organic materials. Moreover, rich metal centers in the structure of MOFs could be catalytic active sites for some chemical reactions.
  • 436
  • 19 Jan 2022
Topic Review
Ecological–Health Risk Assessments of Copper in the Sediments
The ecological and children’s HRA were assessed in all CCDITS (Cited Cu Data in The Sediments). Generally, local point Cu sources (8%) and lithogenic sources were the main controlling factors of Cu concentrations. 
  • 436
  • 26 Jul 2022
Topic Review
Seismic Array
A seismic array is a system of linked seismometers arranged in a regular geometric pattern (cross, circle, rectangular etc.) to increase sensitivity to earthquake and explosion detection. A seismic array differs from a local network of seismic stations mainly by the techniques used for data analysis. The data from a seismic array is obtained using special digital signal processing techniques such as beamforming, which suppress noises and thus enhance the signal-to-noise ratio (SNR). The earliest seismic arrays were built in the 1950s in order to improve the detection of nuclear tests worldwide. Many of these deployed arrays were classified until the 1990s. Today they become part of the IMS as primary or auxiliary stations. Seismic arrays are not only used to monitor earthquakes and nuclear tests, but also used as a tool for investigating nature and source regions of microseisms as well as locating and tracking volcanic tremor and analyzing complex seismic wave-field properties in volcanic areas.
  • 436
  • 29 Sep 2022
Topic Review
Genetic Markers for Metabarcoding of Freshwater Microalgae
The metabarcoding approach is widely used for studying the diversity and distribution of freshwater microalgae and for routine biomonitoring. Due to microalgae being a phylogenetically diverse group, the choice of a genetic marker directly affects the metabarcoding results. Specific markers are good for identifying only concrete groups, while universal markers may miss classes or lack the variability necessary for differentiating taxa at the species and sometimes genus levels. An analysis of publications on the subject showed that metabarcoding studies of eukaryotic freshwater microalgae used 12 markers (different nuclear regions 18S and ITS and plastid regions rbcL, 23S and 16S). Studies that compared outcomes from different markers show that the resulting lists of taxa do not match. The plastid marker rbcL is widely used for diatom metabarcoding, as it differentiates taxa at the species and intraspecies levels, and there is a specific set of primers designed for identifying Eustigmatophyceae. The V9 18S region is more variable than V4 18S and provides more diversity at higher taxonomic levels (supergroup and phylum). The ITS1 and ITS2 regions are used rarely and may be underestimated. These barcodes amplify well with the standard primers and are variable enough to identify sequences at the species level. Plastid markers (23S and 16S rDNA) focused on the plastid-containing eukaryotic algae and Cyanobacteria, conserved regions, identify taxa to the genus level and higher. Using specialized curated databases for data interpretation significantly improves the quality of the results.
  • 436
  • 31 Jul 2023
Topic Review
Geographic Description of North Macedonia
North Macedonia is a landlocked country in the central part of the Balkan Peninsula between 40°50′ and 42°20′ north latitude and between 20°28′ and 23°05′ east longitude, with an area of about 25,700 km2.
  • 435
  • 02 Apr 2024
Topic Review
Molecular to Meteorological
The path from molecular to meteorological scales begins with the persistence of molecular velocity after collision inducing symmetry breaking, from continuous translational to scale invariant, associated with the emergence of hydrodynamic behaviour in a Maxwellian (randomised) population undergoing an anisotropic flux. The statistical multifractal formulation of observed atmospheric variability enables the examination of turbulence. The unexpected correlation between the intermittency of temperature and the ozone photodissociation rate in the lower Arctic stratosphere led to an analysis of the role of Gibbs free energy in the general circulation of the atmosphere, and a suggestion to solve the persistent cold bias in its siumlation by free running numerical models.
  • 434
  • 12 Apr 2022
Topic Review
Chemical and Biological Degradation for Perfluorooctanoic Acid
Perfluorooctanoic acid (PFOA) is a perfluoro compound that contains an eight-carbon perfluoroalkyl chain followed by a carboxylic acid function group. It has found applications in water-resistant coating and is produced either by degrading other long-chain perfluorinated carboxylic acids or fluorotelomer alcohol. PFOA is challenging to further degrade during water treatment processes, leading to its accumulation in natural systems and causing contamination. Research has been conducted to develop several methods for its removal from the water system.
  • 434
  • 01 Dec 2023
Topic Review
Recyclable Design of Wooden Furniture
With the rapid development of the economy and the change in people’s aesthetic concepts, the renewal of furniture has become more and more frequent. Among the huge amount of used furniture, solid wood and wood-based panel furniture account for the vast majority, but the imperfective recycling system and insufficient recycling efforts result in serious waste, which is contrary to the low-carbon transition and sustainable development means. 
  • 434
  • 21 Dec 2023
Topic Review
Polar Vortex Causes Temporal Variability of Solar-Atmospheric Links
The stratospheric polar vortex is a large-scale cyclonic circulation that forms in a cold air mass in the polar region and extends from the middle troposphere to the stratosphere. The polar vortex is implicated in a variety of atmospheric processes, such as the formation of ozone holes, the North Atlantic and the Arctic Oscillations, variations in extratropical cyclone tracks, etc. The vortex plays an important part in the mechanism of solar activity influence on lower atmosphere circulation, with variations in the vortex intensity being responsible for temporal variability in the correlation links observed between atmospheric characteristics and solar activity phenomena. In turn, the location of the vortex is favorable for the influence of ionization changes associated with charged particle fluxes (cosmic rays, auroral and radiation belt electrons) that affect the chemical composition and temperature regime of the polar atmosphere as well as its electric properties and cloudiness state. 
  • 433
  • 08 Aug 2022
Topic Review
Microplastics in Coastal Agglomerations
Microplastics are ubiquitously in various environments from the equator to the poles. Coastal agglomerations act as both a source and sink connecting the global microplastic cycles of oceans and continents. While the problem of microplastics is particularly severe and complex in the coastal zones, where both inland and marine pollution are concentrated, the present research aimed to provide hot topics and trend of coastal urban microplastic studies and to review the researches on microplastic pollution in the atmosphere and water bodies in coastal agglomerations in terms of characteristics, behavior and health threat of microplastics. The results of the bibliometric analysis showed an increase in the annual output of microplastic research. Research hot topics and clusters were analyzed using the VOSviewer. Characteristics of microplastics varied in abundance, size and polymer type in different environments and countries. Furthermore, coastal cities are taken as a system to sort out the input, output, and internal transmission pathways of microplastics. The health threat of microplastics to urban residents was briefly reviewed and the exposure and health risks of microplastics to infants and young children were of particular concern. Detailed and comprehensive studies on intervention and reduction in the transmission of microplastics between the atmosphere and water bodies, whether microplastics are harmful to infants and young children, and measures to reduce the risk of microplastic exposure are needed.
  • 433
  • 11 May 2023
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