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Biography
Nizam Al-Mulk
Abu Ali Hasan ibn Ali Tusi (April 10, 1018 – October 14, 1092), better known by his honorific title of Nizam al-Mulk (Persian: نظام‌الملک‎, lit. 'Order of the Realm'[1]) was a Persian[2][3] scholar, political philosopher and vizier of the Seljuk Empire. Rising from a lowly position,[4] he was the de facto ruler of the empire for 20 years after the assassination of sultan Alp Arsl
  • 5.7K
  • 16 Nov 2022
Topic Review
Sultan
Sultan (/ˈsʌltən/; Arabic: سلطان sulṭān, pronounced [sʊlˈtˤɑːn, solˈtˤɑːn]) is a position with several historical meanings. Originally, it was an Arabic abstract noun meaning "strength", "authority", "rulership", derived from the verbal noun سلطة sulṭah, meaning "authority" or "power". Later, it came to be used as the title of certain rulers who claimed almost full sovereignty in practical terms (i.e., the lack of dependence on any higher ruler), albeit without claiming the overall caliphate, or to refer to a powerful governor of a province within the caliphate. The adjectival form of the word is "sultanic", and the state and territories ruled by a sultan, as well as his office, are referred to as a sultanate (سلطنة salṭanah). The term is distinct from king (ملك malik), despite both referring to a sovereign ruler. The use of "sultan" is restricted to Muslim countries, where the title carries religious significance, contrasting the more secular king, which is used in both Muslim and non-Muslim countries. Brunei and Oman are the only independent countries which retain the title "sultan" for their monarchs. In recent years, the title has been gradually replaced by "king" by contemporary hereditary rulers who wish to emphasize their secular authority under the rule of law. A notable example is Morocco, whose monarch changed his title from sultan to king in 1957.
  • 5.7K
  • 23 Nov 2022
Topic Review
Marine Battery Energy Storage Systems on Ships
The shipping industry is going through a period of technology transition that aims to increase the use of carbon-neutral fuels. There is a significant trend of vessels being ordered with alternative fuel propulsion. Shipping’s future fuel market will be more diverse, reliant on multiple energy sources. One of very promising means to meet the decarbonisation requirements is to operate ships with sustainable electrical energy by integrating local renewables, shore connection systems and battery energy storage systems (BESS). 
  • 5.7K
  • 20 Mar 2023
Biography
John Glenn
Colonel John Herschel Glenn Jr. (July 18, 1921 – December 8, 2016) was a United States Marine Corps aviator, engineer, astronaut, businessman, and politician. He was the first American to orbit the Earth, circling it three times in 1962. Following his retirement from NASA, he served from 1974 to 1999 as a Democratic United States Senator from Ohio. Before joining NASA, Glenn was a distinguis
  • 5.7K
  • 22 Nov 2022
Topic Review
Gallium Nitride High-Electron-Mobility Transistor
In recent years, GaN-based devices have been widely used in a variety of application fields. GaN-based high-electron-mobility transistors (HEMTs) are superior to conventional silicon (Si) based devices in terms of switching frequency, power rating, thermal capability and efficiency, which are crucial factors to enhance the performances of advanced power converters. This paper addresses some fundamental issues concerning intrinsic features of GaN material and key technology in practical application of GaN-based power switching devices.
  • 5.7K
  • 30 Jul 2020
Topic Review
Illegal IPTV Technologies
Technologies providing copyright-infringing IPTV content are commonly used as an illegal alternative to legal IPTV subscriptions and services, as they usually have lower monetary costs and can be more convenient for users who follow content from different sources. These infringing IPTV technologies may include websites, software, software add-ons, and physical set-top boxes. Due to the free or low cost of illegal IPTV technologies, illicit IPTV content providers will often resort to intrusive advertising, scams, and the distribution of malware to increase their revenue.
  • 5.7K
  • 20 Oct 2023
Topic Review
Composite Material Applications
Composite materials are composed of two or more different materials having considerably different physical and/or chemical characteristics that, when merged, produce a material with attributes that differ from the separate elements. Composite materials are extensively utilized in the automobile, construction, transportation, aerospace, and renewable energy applications due to their durability, high strength, great quality, minimal maintenance, and low weight.
  • 5.7K
  • 08 Oct 2021
Topic Review
Catalyst Design via Colloidal Synthesis
Supported nanoparticles are commonly applied in heterogeneous catalysis. The catalytic performance of these solid catalysts is, for a given support, dependent on the nanoparticle size, shape, and composition, thus necessitating synthesis techniques that allow for preparing these materials with fine control over those properties. Such control can be exploited to deconvolute their effects on the catalyst’s performance, which is the basis for knowledge-driven catalyst design. In this regard, bottom-up synthesis procedures based on colloidal chemistry have proven successful in achieving the desired level of control for a variety of fundamental studies. This article aims to give an overview of recent progress made in this synthesis technique for the application of controlled catalytic materials in gas-phase catalysis. The focus goes to mono- and bimetallic materials, as well as to recent efforts in enhancing their performance by embedding colloidal templates in porous oxide phases.
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  • 12 May 2021
Biography
B. F. Skinner
Burrhus Frederic Skinner (March 20, 1904 – August 18, 1990) was an American psychologist, behaviorist, author, inventor, and social philosopher.[1][2][3][4] He was a professor of psychology at Harvard University from 1958 until his retirement in 1974.[5] Considering free will to be an illusion, Skinner saw human action as dependent on consequences of previous actions, a theory he would articu
  • 5.7K
  • 17 Nov 2022
Topic Review
Supercontinent Cycle
The supercontinent cycle is the quasi-periodic aggregation and dispersal of Earth's continental crust. There are varying opinions as to whether the amount of continental crust is increasing, decreasing, or staying about the same, but it is agreed that the Earth's crust is constantly being reconfigured. One complete supercontinent cycle is said to take 300 to 500 million years. Continental collision makes fewer and larger continents while rifting makes more and smaller continents.
  • 5.7K
  • 03 Nov 2022
Topic Review
Shambhala
In Tibetan Buddhist tradition, Shambhala (Sanskrit: शम्भल Śambhala, also spelled Shambala or Shamballa; Tibetan: བདེ་འབྱུང, Wylie: Bde'byung; Chinese: 香巴拉; pinyin: Xiāngbālā) is a mythical kingdom. Shambhala is mentioned in the Kalacakra Tantra. The Bon scriptures speak of a closely related land called Tagzig Olmo Lung Ring. The Sanskrit name is taken from the name of a city mentioned in the Hindu Puranas, probably in reference to Sambhal in Uttar Pradesh. The mythological relevance of the place originates with a prophecy in Vishnu Purana (4.24) according to which Shambhala will be the birthplace of Kalki, the final incarnation of Vishnu, who will usher in a new Age (Satya Yuga).
  • 5.7K
  • 01 Dec 2022
Topic Review
Sarcopterygii
Sarcopterygii (/ˌsɑːrkɒptəˈrɪdʒi.aɪ/; from grc σάρξ (sárx) 'flesh', and πτέρυξ (ptérux) 'wing, fins')—sometimes considered synonymous with Crossopterygii (from grc κροσσός (krossós) 'fringe')—is a taxon (traditionally a class or subclass) of the bony fishes whose members are known as lobe-finned fishes. The group Tetrapoda, a superclass including amphibians, reptiles (including dinosaurs and therefore birds), and mammals, evolved from certain sarcopterygians; under a cladistic view, tetrapods are themselves considered a group within Sarcopterygii. The known extant non-tetrapod sarcopterygians include two species of coelacanths and six species of lungfishes.
  • 5.7K
  • 27 Oct 2022
Topic Review
Social Change
Social change refers to the transformation of societal structures, institutions, and behaviors over time. It involves shifts in values, norms, and practices that impact the way individuals and groups interact, ultimately influencing the broader dynamics of a society. Social change can result from various factors, including technological advancements, cultural evolution, political movements, and economic developments.
  • 5.7K
  • 26 Jan 2024
Topic Review
Sugar Based Surfactants
Sugar-based surfactants are a class of surfactants derived from natural sugars, such as glucose, sucrose, and maltose. These surfactants have gained significant interest in recent years due to their biodegradability, low toxicity, and high compatibility with biological systems. Sugar-based surfactants are classified into two main groups: alkyl polyglucosides (APGs) and saccharide fatty acid esters (SFAEs). APGs are produced by reacting a fatty alcohol with glucose, while SFAEs are produced by esterifying a sugar molecule with a fatty acid. APGs have excellent cleaning and foaming properties and are used in a variety of personal care and household products, including shampoos, body washes, and dishwashing detergents. SFAEs are mainly used in the food industry as emulsifiers and stabilizers. One of the main advantages of sugar-based surfactants is their biodegradability, which means that they break down into harmless substances when exposed to environmental conditions such as sunlight, water, and microorganisms. This makes them an attractive alternative to synthetic surfactants, which can persist in the environment for a long time and have negative impacts on ecosystems.
  • 5.7K
  • 24 Mar 2023
Topic Review
Overall Equipment Effectiveness
Overall equipment effectiveness (OEE) is a key performance indicator used to measure equipment productivity. The purpose of this study is to review and analyze the evolution of OEE, present modifications made over the original model and identify future development areas.
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  • 12 Apr 2021
Topic Review
Beta-Carotene
β-Carotene is an organic, strongly coloured red-orange pigment abundant in fungi, plants, and fruits. It is a member of the carotenes, which are terpenoids (isoprenoids), synthesized biochemically from eight isoprene units and thus having 40 carbons. Among the carotenes, β-carotene is distinguished by having beta-rings at both ends of the molecule. β-Carotene is biosynthesized from geranylgeranyl pyrophosphate. In some Mucoralean fungi, β-Carotene is a precursor to the synthesis of trisporic acid. β-Carotene is the most common form of carotene in plants. When used as a food coloring, it has the E number E160a.:119 The structure was deduced by Karrer et al. in 1930. In nature, β-carotene is a precursor (inactive form) to vitamin A via the action of beta-carotene 15,15'-monooxygenase. Isolation of β-carotene from fruits abundant in carotenoids is commonly done using column chromatography. It can also be extracted from the beta-carotene rich algae, Dunaliella salina. The separation of β-carotene from the mixture of other carotenoids is based on the polarity of a compound. β-Carotene is a non-polar compound, so it is separated with a non-polar solvent such as hexane. Being highly conjugated, it is deeply colored, and as a hydrocarbon lacking functional groups, it is very lipophilic.
  • 5.7K
  • 16 Nov 2022
Topic Review
Half-Reaction
A half reaction (or half-cell reaction) is either the oxidation or reduction reaction component of a redox reaction. A half reaction is obtained by considering the change in oxidation states of individual substances involved in the redox reaction. Often, the concept of half reactions is used to describe what occurs in an electrochemical cell, such as a Galvanic cell battery. Half reactions can be written to describe both the metal undergoing oxidation (known as the anode) and the metal undergoing reduction (known as the cathode). Half reactions are often used as a method of balancing redox reactions. For oxidation-reduction reactions in acidic conditions, after balancing the atoms and oxidation numbers, one will need to add H+ ions to balance the hydrogen ions in the half reaction. For oxidation-reduction reactions in basic conditions, after balancing the atoms and oxidation numbers, first treat it as an acidic solution and then add OH− ions to balance the H+ ions in the half reactions (which would give H2O).
  • 5.7K
  • 28 Nov 2022
Topic Review Peer Reviewed
Amanita muscaria: Ecology, Chemistry, Myths
Amanita muscaria is the most emblematic mushroom in the popular representation. It is an ectomycorrhizal fungus endemic to the cold ecosystems of the northern hemisphere. The basidiocarp contains isoxazoles compounds that have specific actions on the central nervous system, including hallucinations. For this reason, it is considered an important entheogenic mushroom in different cultures whose remnants are still visible in some modern-day European traditions. In Siberian civilizations, it has been consumed for religious and recreational purposes for millennia, as it was the only inebriant in this region.
  • 5.7K
  • 13 Apr 2022
Topic Review
Leucine Metabolism
Leucine, an essential branched amino acid, has anti-obesity effects on glucose tolerance, lipid metabolism, and insulin sensitivity. The catabolism of Leucine is a conserved regulator of physiological aging, participating in diverse physiological and pathological processes. This topic review offers an up-to-date report on the decomposition and metabolites of leucine in mammals, as α-ketoisocaproate (KIC) and β-hydroxy-β-methylbutyrate (HMB).
  • 5.7K
  • 29 Oct 2020
Topic Review
Internet of Things in the Industry Revolution 4.0
Researchers offers a wide range of information on Industry 4.0, finds research gaps and recommends future directions. Seven research questions are addressed: (i) What are the contributions of WSN in IR 4.0? (ii) What are the contributions of IoT in IR 4.0? (iii) What are the types of WSN coverage areas for IR 4.0? (iv) What are the major types of network intruders in WSN and IoT systems? (v) What are the prominent network security attacks in WSN and IoT? (vi) What are the significant issues in IoT and WSN frameworks? and (vii) What are the limitations and research gaps in the existing work? Researchers mainly focuses on the solutions and new techniques to automate Industry 4.0 and analyzed over 130 articles from 2014 until 2021. The entry covers several aspects of Industry 4.0, from the designing phase to security needs, from the deployment stage to the classification of the network, the difficulties, challenges, and future directions.
  • 5.7K
  • 16 Mar 2022
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