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Topic Review
Metal-Organic Frameworks
Metal-organic frameworks represent a porous class of materials that are build up from metal ions or oligonuclear metallic complexes and organic ligands. They can be considered as sub-class of coordination polymers and can be extended into one-dimension, two-dimensions, and three-dimensions. Depending on the size of the pores, MOFs are divided into nanoporous, mesoporous, and macroporous items. The latter two are usually amorphous. MOFs display high porosity, a large specific surface area, and high thermal stability due to the presence of coordination bonds. The pores can incorporate neutral molecules, such as solvent molecules, anions, and cations, depending on the overall charge of the MOF, gas molecules, and biomolecules. The structural diversity of the framework and the multifunctionality of the pores render this class of materials as candidates for a plethora of environmental and biomedical applications and also as catalysts, sensors, piezo/ferroelectric, thermoelectric, and magnetic materials.
  • 3.8K
  • 13 Jan 2021
Topic Review
Hydrogen Storage Technologies for Railway Engineering
According to the specific requirements of railway engineering, a techno-economic comparison for onboard hydrogen storage technologies is conducted to discuss their feasibility and potentials for hydrogen-powered hybrid trains. Physical storage methods, including compressed hydrogen (CH2), liquid hydrogen (LH2), and cryo-compressed hydrogen (CcH2), and material-based (chemical) storage methods, such as ammonia, liquid organic hydrogen carriages (LOHCs), and metal hydrides, are carefully discussed in terms of their operational conditions, energy capacity, and economic costs.
  • 3.8K
  • 23 Sep 2022
Topic Review
Innovative Preservation Methods Applied to Fish Products
Fish products are highly perishable, requiring proper processing to maintain their quality and safety during the entire storage. Different from traditional methods used to extend the shelf-life of these products (smoking, salting, marinating, icing, chilling, freezing, drying, boiling, steaming, etc.), in recent years, some alternative methods (non-thermal atmospheric plasma (NTAP), pulsed electric fields (PEF), pulsed light (PL), ultrasounds (US) and electrolyzed water (EW)) have been proposed as innovative processing technologies able to guarantee the extension of their shelf-life while minimally affecting their organoleptic properties. 
  • 3.8K
  • 13 Jan 2022
Topic Review
88 Modern Constellations
In contemporary astronomy, the sky is divided into 88 regions called constellations, generally based on the asterisms (which are also called "constellations") of Greek and Roman mythology. The number of 88, along with the contemporary scientific notion of "constellation", was conventioned in 1922 by the International Astronomical Union in order to establish a universal pattern for professional astronomers, who defined constellations from then on as regions of the sky separated by arcs of right ascensions and declinations and grouped by asterisms of their historically most important stars, which cover the entire celestial sphere. The constellations along the ecliptic are called the zodiac. The ancient Sumerians, and later the Greeks (as recorded by Ptolemy), established most of the northern constellations in international use today. When explorers mapped the stars of the southern skies, European and American astronomers proposed new constellations for that region, as well as ones to fill gaps between the traditional constellations. Not all of these proposals caught on, but in 1922, the International Astronomical Union (IAU) adopted the modern list of 88 constellations. After this, Eugène Joseph Delporte drew up precise boundaries for each constellation, so that every point in the sky belonged to exactly one constellation.
  • 3.8K
  • 08 Oct 2022
Topic Review
MOSE Project
MOSE (MOdulo Sperimentale Elettromeccanico, Experimental Electromechanical Module) is a project intended to protect the city of Venice, Italy, and the Venetian Lagoon from flooding. The project is an integrated system consisting of rows of mobile gates installed at the Lido, Malamocco, and Chioggia inlets that are able to isolate the Venetian Lagoon temporarily from the Adriatic Sea during acqua alta high tides. Together with other measures, such as coastal reinforcement, the raising of quaysides, and the paving and improvement of the lagoon, MOSE is designed to protect Venice and the lagoon from tides of up to 3 metres (9.8 ft). The Consorzio Venezia Nuova is responsible for the work on behalf of the Ministry of Infrastructure and Transport – Venice Water Authority. Construction began simultaneously in 2003. On 10 July 2020, the first full test was successfully completed, and after multiple delays, cost overruns, and scandals resulted in the project missing its 2018 completion deadline (originally a 2011 deadline) it is now expected to be fully completed by the end of 2021.
  • 3.8K
  • 10 Oct 2022
Topic Review
Physical, Chemical, and Environmental Properties of Phthalates
Phthalic acid esters (PAEs), commonly named phthalates, are a class of dialkyl or alkyl/aryl esters of phthalic acid (1,2-benzenedicarboxylic acid) structured in one benzene ring linked with two aliphatic ester groups, most commonly in the ortho configuration.
  • 3.8K
  • 13 Jun 2023
Topic Review
Enzymatic Transesterification in Biodiesel Production
       Biodiesel constitutes an attractive source of energy because it is renewable,  biodegradable, and non-polluting. Up to 20% biodiesel can be blended with fossil diesel and is being produced and used in many countries. Biodiesel is produced through the transesterification reaction of fat waste with a short-chain alcohol, usually methanol, in the presence of a catalyst. Animal fats, usually found as waste from slaughterhouses, meat processing industry, and cooking facilities, constitute an important waste with costly treatment that can be reduced if used as feedstock for biodiesel production. Animal fat waste represents near 6% of total feedstock used to produce biodiesel through alkaline catalysis transesterification after its pretreatment. Lipase transesterification has some advantages such as the requirement of mild conditions, absence of pretreatment, no soap formation, simple downstream purification process and generation of high quality biodiesel. However, it has some disadvantages like the cost of the enzyme, its poor stability, and the enzyme deactivation by alcohol, that can be partly overcome through enzyme immobilization. A few companies are using liquid lipase formulations and, in some cases, immobilized lipases for industrial biodiesel production.        Biodiesel constitutes an attractive source of energy because it is renewable,  biodegradable, and non-polluting. Up to 20% biodiesel can be blended with fossil diesel and is being produced and used in many countries. Biodiesel is produced through the transesterification reaction of fat waste with a short-chain alcohol, usually methanol, in the presence of a catalyst. Animal fats, usually found as waste from slaughterhouses, meat processing industry, and cooking facilities, constitute an important waste with costly treatment that can be reduced if used as feedstock for biodiesel production. Animal fat waste represents near 6% of total feedstock used to produce biodiesel through alkaline catalysis transesterification after its pretreatment. Lipase transesterification has some advantages such as the requirement of mild conditions, absence of pretreatment, no soap formation, simple downstream purification process and generation of high quality biodiesel. However, it has some disadvantages like the cost of the enzyme, its poor stability, and the enzyme deactivation by alcohol, that can be partly overcome through enzyme immobilization. A few companies are using liquid lipase formulations and, in some cases, immobilized lipases for industrial biodiesel production.
  • 3.8K
  • 30 Oct 2020
Topic Review Peer Reviewed
Social Cohesion: Definitions, Causes and Consequences
Viewed as the glue that binds societies, social cohesion is considered an essential ingredient to address common societal challenges. Definitions and associated conceptual frameworks usually summarise social cohesion as collective attributes and behaviours characterised by positive social relations, a sense of identification or belonging, and an orientation towards the common good. However, there are a large variety of definitions, and disagreement exists about what constitutes the core components, causes and consequences of social cohesion.
  • 3.8K
  • 30 Aug 2023
Topic Review
Industrialization
Industrialization is the process of transforming an economy from primarily agrarian and manual labor-based into one dominated by manufacturing and industry. It involves the widespread adoption of mechanized production methods, the establishment of factories, and the utilization of advanced technologies to increase productivity. This societal shift, historically associated with the 18th and 19th centuries, has profound implications for economic structures, labor markets, and overall societal development.
  • 3.8K
  • 25 Jan 2024
Topic Review
Orthopoxviruses
Zoonotic diseases, defined as diseases or infections that are naturally transmissible from vertebrate animals to humans, represent a significant threat to global health. Among the species recognized as pathogenic to humans, more than half originated in animals, and some have been characterized as emerging or re-emerging pathogens. Most zoonotic pathogens originated in wild and domesticated mammalian hosts such as bats, rodents, and primates. The analysis of global trends indicates that new zoonotic threats will continue to emerge at an accelerating rate, and are mainly associated with an growthing population, changes in land use, climate changes, increased intercontinental travel, and expanded trade networks. Poxviruses are among mankind’s longest and best-known viruses mainly because of their most feared and lethal representative, Variola virus (VARV), the causative agent of smallpox. Orthopoxvirus is the most important and well-characterized poxvirus genus, mainly due to its impact on human and animal health. Orthopoxviruses are remarkable for their wide host spectrum, ranging from humans to domestic and wild animals.
  • 3.8K
  • 22 Jan 2021
Topic Review
Resveratrol in Kidney Disease
Different diseases and disorders that affect the kidneys include, but are not limited to, glomerulonephritis, diabetic nephropathy, polycystic kidney disease, kidney stones, renal fibrosis, sepsis, and renal cell carcinoma. Kidney disease tends to develop over many years, making it difficult to identify until much later when kidney function is severely impaired and undergoing kidney failure. Epidemiological studies have suggested that a diet rich in fruits and vegetables is associated with health benefits including protection against kidney disease and renal cancer. Resveratrol, a polyphenol found in grapes and berries, has been reported to have antioxidant, anti-inflammatory, antidiabetic, hepatoprotective, neuroprotective, and anti-cancer properties.
  • 3.8K
  • 13 Sep 2021
Topic Review Peer Reviewed
Metal Binding Proteins
Metal ions play several major roles in proteins: structural, regulatory, and enzymatic. The binding of some metal ions increase stability of proteins or protein domains. Some metal ions can regulate various cell processes being first, second, or third messengers. Some metal ions, especially transition metal ions, take part in catalysis in many enzymes. From ten to twelve metals are vitally important for activity of living organisms: sodium, potassium, magnesium, calcium, manganese, iron, cobalt, zinc, nickel, vanadium, molybdenum, and tungsten. This short review is devoted to structural, physical, chemical, and physiological properties of proteins, which specifically bind these metal cations.
  • 3.8K
  • 18 Apr 2022
Topic Review
Postal Censorship
Postal censorship is the inspection or examination of mail, most often by governments. It can include opening, reading and total or selective obliteration of letters and their contents, as well as covers, postcards, parcels and other postal packets. Postal censorship takes place primarily but not exclusively during wartime (even though the nation concerned may not be at war, e.g. Ireland during 1939–1945) and periods of unrest, and occasionally at other times, such as periods of civil disorder or of a state of emergency. Both covert and overt postal censorship have occurred. Historically, postal censorship is an ancient practice; it is usually linked to espionage and intelligence gathering. Both civilian mail and military mail may be subject to censorship, and often different organisations perform censorship of these types of mail. In 20th-century wars the objectives of postal censorship encompassed economic warfare, security and intelligence. The study of postal censorship is a philatelic topic of postal history.
  • 3.8K
  • 01 Dec 2022
Topic Review
Current-Source Inverter
This entry addresses the topologies of the single-stage isolated matrix inverters with a grid-side switching stage based on the current source inverter (CSI). These inverters have been proposed for the uninterruptible power supplies, high and low-voltage/power photovoltaic systems, low-power fuel cell, different low- and high-voltage battery and/or electric vehicle chargers, audio amplifiers. The fully controlled switches on both terminals of these converters typically can provide the bidirectional power transfer capability, which is also addressed for most of the topologies. The other advantages include soft-switching of semiconductors and absence of the bulky DC-link capacitor. Average efficiency of today’s isolated matrix inverters is comparable with the two-stage power converters; however, due to absence of DC-link they can provide higher reliability and lower cost.
  • 3.8K
  • 28 Oct 2020
Topic Review
Measuring Grain Loss during Harvest in Paddy Field
A combine harvester has been widely employed for harvesting paddy in Malaysia. However, it is one of the most challenging machines to operate when harvesting grain crops. Improper handling of a combine harvester can lead to a significant amount of grain loss. Any losses during the harvesting process would result in less income for the farmers.
  • 3.8K
  • 28 Mar 2022
Topic Review
Sustainable Urban Mobility
Sustainable urban mobility is a term that refers to the use of means of transport that do not affect the environment and an approach to the planning of the development of urban areas with sustainability goals in mind. When creating sustainable urban mobility plans, planners must also have the number of inhabitants in urban areas in mind as well as the need to ensure a satisfactory transportation service for residents located in urban areas. In order to respond to the ever-increasing need to develop sustainable modes of transport, the importance of electric, autonomous, and electric autonomous vehicles is increasingly emphasized. In addition, as trends of growth and development in electric autonomous vehicle technology are increasing, one of the questions that has appeared is whether autonomous electric vehicles represent one of the mechanisms that will be used to increase the sustainability of urban mobility. 
  • 3.8K
  • 20 Jun 2025
Topic Review
Extraction of Metals from Copper Tailings through Leaching
A copper tailing is a residue, product of the flotation of sulfide minerals, which contain a variety of elements that can be valorized. The extraction of metals from copper tailings consist of applying metallurgical techniques, such as acid leaching or magnetic concentration, to obtain a valuable product. Currently, this is an important objective, given that mining operations have increased the generation of tailings. Acid leaching is a process that consists of dissolving a solid material, such as a tailing, by applying an acid solution. This process forms two final products: an insoluble solid, rich in aluminosilicates, and an acid liquid solution with different metal ions. Both products may have different characteristics and can be used for subsequent applications.
  • 3.8K
  • 05 Dec 2022
Topic Review
Food Composition Databases
Food databases (FDB), or more correctly food composition databases, contain detailed information on the nutritional composition of foods and on other relevant compounds (e.g., polyphenols, phytic acid). Food components primarily determine nutritional features and, in some cases, quality aspects. For example, polyphenols, which are abundant in plants, are often associated to bitter taste and astringency sensation of foods, while acting in favour of food safety by inhibiting foodborne pathogens and spoilage microbes.
  • 3.8K
  • 13 Sep 2021
Topic Review
Robot Bionic Vision Technologies
The visual organ is important for animals to obtain information and understand the outside world; however, robots cannot do so without a visual system. At present, the vision technology of artificial intelligence has achieved automation and relatively simple intelligence; however, bionic vision equipment is not as dexterous and intelligent as the human eye. At present, robots can function as smartly as human beings; however, existing reviews of robot bionic vision are still limited. Robot bionic vision has been explored in view of humans and animals’ visual principles and motion characteristics. 
  • 3.8K
  • 25 Aug 2022
Topic Review
Maya Script
Maya script, also known as Maya glyphs, was the writing system of the Maya civilization of Mesoamerica and is the only Mesoamerican writing system that has been substantially deciphered. The earliest inscriptions found which are identifiably Maya date to the 3rd century BCE in San Bartolo, Guatemala. Maya writing was in continuous use throughout Mesoamerica until the Spanish conquest of the Maya in the 16th and 17th centuries. Maya writing used logograms complemented with a set of syllabic glyphs, somewhat similar in function to modern Japanese writing. Maya writing was mistakenly called "hieroglyphics" or hieroglyphs by early European explorers of the 18th and 19th centuries who found its general appearance reminiscent of Egyptian hieroglyphs, although the two systems are unrelated. Modern Mayan languages are written using the Latin alphabet rather than Maya script.
  • 3.8K
  • 21 Nov 2022
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