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Topic Review
Antioxidant Properties of Ascorbic Acid
Ascorbic acid, commonly known as vitamin C, is one of the basic and best-known compounds necessary for the proper functioning of the human body. Ascorbic acid, as a one of the basic exogenous vitamins, occurs in the body in the form of ascorbate, known for its strong antioxidant and anti-inflammatory properties.
  • 3.9K
  • 18 Oct 2022
Topic Review
Christian State
A Christian state is a country that recognizes a form of Christianity as its official religion and often has a state church (also called an established church), which is a Christian denomination that supports the government and is supported by the government. Historically, the nations of Armenia, Aksum, Georgia, as well as the Roman Empire and Byzantine Empire declared themselves as Christian states. In the Middle Ages, the idea to establish a Pan-Christian state by uniting the countries within Christendom, became popular, along with the goal to recover territory in which Christianity historically flourished, such as the Middle East and North Africa. Today, several nations officially identify themselves as Christian states or have state churches, including Argentina , Costa Rica, Denmark (incl. Greenland), Dominican Republic, El Salvador, England , Faroe Islands, Georgia, Greece, Hungary, Iceland, Liechtenstein, Malta, Monaco, Norway , Samoa, Tonga, Tuvalu, Vatican City, and Zambia. A Christian state stands in contrast to a secular state, an atheist state, or another religious state, such as a Jewish state, or an Islamic state.
  • 3.9K
  • 29 Sep 2022
Topic Review
Drop-in Biofuels
Drop-in biofuels have a plant based origin and can be blended gradually into the existing fuel mix. The usage of drop-in biofuels ensures that little to no adjustments are required relative to existing fuel infrastructure. Non drop-in biofuels include alcohols such as (m)ethanol and gaseous fuels which cannot be used in a diesel engine without adjustments. In this study, the potential of drop-in biofuels is addressed. Based on their suitability as a marine fuel and their drop-in character, five drop-in biofuels are selected. These fuels include Fatty Acid Methyl Esters (FAME), Hydrotreated Vegetable Oil (HVO), Fast-Pyrolysis with full hydrodeoxygenation (FP), Hydrothermal Liquefaction with full hydrodeoxygenation (HTL) and Gasification with consequent Fischer–Tropsch synthesis (GFT). 
  • 3.9K
  • 16 Sep 2021
Topic Review
Climate Fiction
Climate fiction (sometimes shortened cli-fi) is literature that deals with climate change and global warming. Not necessarily speculative in nature, works may take place in the world as we know it or in the near future. University courses on literature and environmental issues may include climate change fiction in their syllabi. This body of literature has been discussed by a variety of publications, including The New York Times , The Guardian , and Dissent magazine, among other international media outlets.
  • 3.9K
  • 14 Oct 2022
Topic Review
Medium-Entropy Alloy
The objective of this study is to strengthen the FCC structued medium-entropy alloy using the hard carbides.
  • 3.9K
  • 26 Aug 2020
Topic Review
Eco-Friendly Clothing Market in Bangladesh
Organic cotton clothing development in the fashion industry could play an important role in textile and environmental pollution and create new business opportunities for green clothes.  Consumer environmental concerns and consumer attitudes positively impact the OCC purchase willingness of Bangladeshi consumers. Also, the authenticity and fashionable of OCC products have a significant impact on Bangladeshi consumer purchase intention. Product Performance found an indirect effect on Bangladeshi consumers’ intention. 
  • 3.9K
  • 27 May 2022
Topic Review
Energiewende in Germany
The Energiewende (German for energy transition) is the planned transition by Germany to a low carbon, environmentally sound, reliable, and affordable energy supply. The term Energiewende is regularly used in English language publications without being translated (a loanword).:4 The new system will rely heavily on renewable energy (particularly wind, photovoltaics, and hydroelectricity), energy efficiency, and energy demand management. Most if not all existing coal-fired generation will need to be retired. The phase-out of Germany's fleet of nuclear reactors, to be complete by 2022, is a key part of the program. Legislative support for the Energiewende was passed in late 2010 and includes greenhouse gas (GHG) reductions of 80–95% by 2050 (relative to 1990) and a renewable energy target of 60% by 2050. These targets are ambitious. The Berlin-based policy institute Agora Energiewende noted that "while the German approach is not unique worldwide, the speed and scope of the Energiewende are exceptional". The Energiewende also seeks a greater transparency in relation to national energy policy formation. Germany has made significant progress on its GHG emissions reduction target, achieving a 27% decrease between 1990 and 2014. However the country will need to maintain an average GHG emissions abatement rate of 3.5% per year to reach its Energiewende goal, equal to the maximum historical value thus far. As of 2013, Germany spends €1.5 billion per year on energy research in an effort to solve the technical and social issues raised by the transition. This includes a number of computer studies that have confirmed the feasibility and a similar cost (relative to business-as-usual and given that carbon is adequately priced) of the Energiewende.
  • 3.9K
  • 09 Oct 2022
Topic Review
Containment Building
A containment building, in its most common usage, is a reinforced steel, concrete or lead structure enclosing a nuclear reactor. It is designed, in any emergency, to contain the escape of radioactive steam or gas to a maximum pressure in the range of 275 to 550 kPa (40 to 80 psi) . The containment is the fourth and final barrier to radioactive release (part of a nuclear reactor's defence in depth strategy), the first being the fuel ceramic itself, the second being the metal fuel cladding tubes, the third being the reactor vessel and coolant system. Each nuclear plant in the US is designed to withstand certain conditions which are spelled out as "Design Basis Accidents" in the Final Safety Analysis Report (FSAR). The FSAR is available for public viewing, usually at a public library near the nuclear plant. The containment building itself is typically an airtight steel structure enclosing the reactor normally sealed off from the outside atmosphere. The steel is either free-standing or attached to the concrete missile shield. In the United States , the design and thickness of the containment and the missile shield are governed by federal regulations (10 CFR 50.55a), and must be strong enough to withstand the impact of a fully loaded passenger airliner without rupture. While the containment plays a critical role in the most severe nuclear reactor accidents, it is only designed to contain or condense steam in the short term (for large break accidents) and long term heat removal still must be provided by other systems. In the Three Mile Island accident the containment pressure boundary was maintained, but due to insufficient cooling, some time after the accident, radioactive gas was intentionally let from containment by operators to prevent over pressurization. This, combined with further failures, caused the release of up to 13 million curies of radioactive gas to atmosphere during the accident. While the Fukushima Daiichi plant had operated safely since 1971, an earthquake and tsunami well beyond the design basis resulted in failure of AC power, backup generators and batteries which defeated all safety systems. These systems were necessary to keep the fuel cool after the reactor had been shut down. This resulted in partial or complete meltdown of fuel rods, damage to fuel storage pools and buildings, release of radioactive debris to surrounding area, air and sea, and resorting to the expedient use of fire engines and concrete pumps to deliver cooling water to spent fuel pools and containment. During the incident, pressure within the containments of reactors 1-3 rose to exceed design limits, which despite attempts to reduce pressure by venting radioactive gases, resulted in breach of containment. Hydrogen leaking from the containment mixed with air into an explosive mixture which resulted in explosions in Unit 1, 3 and 4, complicating attempts to stabilize the reactors.
  • 3.9K
  • 08 Nov 2022
Topic Review Peer Reviewed
Mechanics and Natural Philosophy in History
This entry presents a historical view of the meaning attributed to the terms mechanics and natural philosophy, from a hint to ancient Greece, the Middle Ages, and the Renaissance to a special focus on the 18th Century, which represents a turning point for the development of modern physics and science in general. Since we are not concerned with the summation of the histories of natural philosophy and mechanics, but only with their interrelations, this makes a detailed description of the two disciplines unnecessary.
  • 3.9K
  • 15 Sep 2022
Topic Review
Sangha
Sangha is a Sanskrit word used in many Indian languages, including Pali(saṅgha)meaning "association", "assembly", "company" or "community". It was historically used in a political context to denote a governing assembly in a republic or a kingdom. It is used in modern times by groups such as the political party and social movement Rashtriya Seva Sangh. It has long been commonly used by religious associations including by Buddhists,Jains and Sikhs. In Buddhism, sangha refers to the monastic community of bhikkhus (monks) and bhikkhunis (nuns). These communities are traditionally referred to as the bhikkhu-sangha or bhikkhuni-sangha. As a separate category, those who have attained any of the four stages of enlightenment, whether or not they are members of the monastic community, are referred to as the āryasaṅgha "noble Sangha". According to the Theravada school, the term "sangha" does not refer to the community of sāvakas (lay followers) nor the community of Buddhists as a whole.
  • 3.9K
  • 23 Nov 2022
Topic Review
GeForce 2 Series
The GeForce 2 series (NV15) is the second generation of Nvidia's GeForce graphics processing units (GPUs). Introduced in 2000, it is the successor to the GeForce 256. The GeForce 2 family comprised a number of models: GeForce 2 GTS, GeForce 2 Pro, GeForce 2 Ultra, GeForce 2 Ti, GeForce 2 Go and the GeForce 2 MX series. In addition, the GeForce 2 architecture is used for the Quadro series on the Quadro 2 Pro, 2 MXR, and 2 EX cards with special drivers meant to accelerate computer-aided design applications.
  • 3.9K
  • 28 Nov 2022
Topic Review
Lipid and Polymeric Nanoparticles for Brain Drug Delivery
Intranasal administration has gained an increasing interest for brain drug delivery since it allows direct transport through neuronal pathways, which can be quite advantageous for central nervous system disorders, such as depression and anxiety. Nanoparticles have been studied as possible alternatives to conventional formulations, with the objective of improving drug bioavailability.
  • 3.9K
  • 15 Dec 2022
Topic Review
Electrochemical Biosensors for Hormone Detection
Hormones are secreted primarily by glands or specific cells, circulate in the bloodstream, and specialize in targeting cells. The electrochemical biosensing of hormones has emerged for treating human diseases and performing clinical diagnosis.
  • 3.9K
  • 13 Jan 2021
Topic Review
High-explosive Anti-tank Warhead
A high-explosive anti-tank (HEAT) warhead is a type of shaped charge explosive that uses the Munroe effect to penetrate thick tank armor. The warhead functions by having the explosive charge collapse a metal liner inside the warhead into a high-velocity superplastic jet. This superplastic jet is capable of penetrating armor steel to a depth of seven or more times the diameter of the charge (charge diameters, CD) but is usually used to immobilize or destroy tanks. Due to the way they work, they do not have to be fired as fast as an armor piercing shell, allowing less recoil. Contrary to a widespread misconception (possibly resulting from the acronym HEAT), the jet does not melt its way through armor, as its effect is purely kinetic in nature. The HEAT warhead has become less effective against tanks and other armored vehicles due to the use of composite armor, explosive-reactive armor, and active protection systems which destroy the HEAT warhead before it hits the tank. While HEAT ammunition has become less effective against the composite armor found on MBTs from 1964 onward and today pose little threat to any modern tank, they are still deadly against lighter vehicles. In addition, air vehicles are also possible targets.
  • 3.9K
  • 01 Nov 2022
Topic Review
Implant–Abutment Connections
Different implant–abutment connections have been developed to reduce mechanical and biological failure. The most frequent complications are loss of preload, screw loosening, abutment or implant fracture, deformations at the different interfaces, and bacterial microleakage.  To review the evidence indicating whether the implant–abutment connection type is significant regarding the following issues: (1) maintenance of the preload in static and dynamic in vitro studies; (2) assessment of possible deformations at the implant–abutment interfaces, after repeated application of the tightening torque; (3) evaluation of the sealing capability of different implant connections against microleakage. 
  • 3.9K
  • 08 Dec 2020
Topic Review
Pinus
The pine (Pinus L.) is the largest and most heteromorphic plant genus of the pine family (Pinaceae Lindl. ), which grows almost exclusively in the northern hemisphere. The demand for plant-based remedies, supplements and functional food is growing worldwide.
  • 3.9K
  • 17 Jan 2022
Topic Review
Spin
Spin is an intrinsic form of angular momentum carried by elementary particles, and thus by composite particles (hadrons) and atomic nuclei. Spin is one of two types of angular momentum in quantum mechanics, the other being orbital angular momentum. The orbital angular momentum operator is the quantum-mechanical counterpart to the classical angular momentum of orbital revolution and appears when there is periodic structure to its wavefunction as the angle varies. For photons, spin is the quantum-mechanical counterpart of the polarization of light; for electrons, the spin has no classical counterpart. The existence of electron spin angular momentum is inferred from experiments, such as the Stern–Gerlach experiment, in which silver atoms were observed to possess two possible discrete angular momenta despite having no orbital angular momentum. The existence of the electron spin can also be inferred theoretically from the spin–statistics theorem and from the Pauli exclusion principle—and vice versa, given the particular spin of the electron, one may derive the Pauli exclusion principle. Spin is described mathematically as a vector for some particles such as photons, and as spinors and bispinors for other particles such as electrons. Spinors and bispinors behave similarly to vectors: they have definite magnitudes and change under rotations; however, they use an unconventional "direction". All elementary particles of a given kind have the same magnitude of spin angular momentum, though its direction may change. These are indicated by assigning the particle a spin quantum number. The SI unit of spin is the same as classical angular momentum (i.e., N·m·s, J·s, or kg·m2·s−1). In practice, spin is given as a dimensionless spin quantum number by dividing the spin angular momentum by the reduced Planck constant ħ, which has the same dimensions as angular momentum, although this is not the full computation of this value. Very often, the "spin quantum number" is simply called "spin". The fact that it is a quantum number is implicit.
  • 3.9K
  • 27 Oct 2022
Topic Review
Nickel Laterite Deposit
Tectonic emplacement of variably serpentinized ultramafic host rock on land and subsequent chemical weathering under humid tropical to subtropical conditions results in the formation of nickel laterite deposits. Nickel laterites typically occur as weathering mantle over ophiolite complexes, as well as komatiites and layered complexes in Archean to Phanerozoic stable cratonic platforms.
  • 3.9K
  • 01 Apr 2022
Topic Review
Src Non-Receptor Tyrosine Kinase
Src non-receptor tyrosine kinase phosphorylates a variety of protein substrates that perform specific cellular functions. Activity of Src is regulated by a variety of stimuli and the Src protein is subjected to several types of post-translational modifications including lipidation, phosphorylation, acetylation, ubiquitylation, sumoylation and oxidation. In particular, p-Tyr416 Src has been known to be an active form while p-Tyr527 Src is an inactive form through autoinhibition by binding to Src SH2 own domain.
  • 3.9K
  • 23 May 2022
Topic Review
Bloom's Taxonomy
Bloom's taxonomy is a set of three hierarchical models used to classify educational learning objectives into levels of complexity and specificity. The three lists cover the learning objectives in cognitive, affective and sensory domains. The cognitive domain list has been the primary focus of most traditional education and is frequently used to structure curriculum learning objectives, assessments and activities. The models were named after Benjamin Bloom, who chaired the committee of educators that devised the taxonomy. He also edited the first volume of the standard text, Taxonomy of Educational Objectives: The Classification of Educational Goals.
  • 3.9K
  • 24 Oct 2022
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