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Topic Review
Carbon Anode
Carbon anode refers to a broad family of essentially pure carbon, whose members can be tailored to vary widely in their strength, density, conductivity, pore structure, and crystalline development. These attributes contribute to their widespread applicability. Specific characteristics are imparted to the finished product by controlling the selection of precursor materials (including cokes, polymers and fibers) and the method of processing. In general, carbon anode electrodes are characterized by low cost production, high surface area, a wide working potential window in many media, high electrocatalytic activities for different redox-active chemical and biochemical systems, and chemical inertness.Moreover, their surface chemistry enables the functionalization of these carbon platforms via strong covalent or noncovalent methods with surface modifiers, which improves their electrochemical performance. Recent achievements of carbon anode materials and their structural design for better performances of aluminium production, lithium-ion secondary batteries, lithium cobalt oxide batteries, nano-tube production, substitution of amorphous electrode materials, photoanodes production, solar cells, fuel cells, supercapacitors, sensors and pumps, neurochemical monitors, etc., are finding enormous applications in industrial, commercial and social sectors. 
  • 7.4K
  • 31 Aug 2021
Topic Review
Early Germanic Law
Early Germanic law was the form of law followed by the early Germanic peoples. It was an important element of early Germanic culture. Several Latin law codes of the Germanic peoples written in the Early Middle Ages after the Fall of the Western Roman Empire (also known as leges barbarorum "laws of the barbarians") survive, dating to between the 5th and 9th centuries. They are influenced by Roman law, canon law, and earlier tribal customs. Central and West European Germanic law differed from North Germanic law. Germanic law was codified in writing under the influence of Roman law; previously it was held in the memory of designated individuals who acted as judges in confrontations and meted out justice according to customary rote, based on careful memorization of precedent. Among the Franks they were called rachimburgs. "Living libraries, they were law incarnate, unpredictable and terrifying." Power, whose origins were at once said to be magical, divine, and military, was, according to Michel Rouche, exercised jointly by the "throne-worthy" elected king and his free warrior companions. Oral law sufficed as long as the warband was not settled in one place. Germanic law made no provisions for the public welfare, the res publica of Romans. The language of all these continental codes was Latin; the only known codes drawn up in any Germanic language were the Anglo-Saxon laws, beginning with the Laws of Æthelberht (7th century). In the 13th century customary Saxon law was codified in the vernacular as the Sachsenspiegel. All these laws may be described in general as codes of governmental procedure and tariffs of compositions. They all present somewhat similar features with Salic law, the best-known example, but often differ from it in the date of compilation, the amounts of fines, the number and nature of the crimes, the number, rank, duties and titles of the officers, etc. In Germanic Europe in the Early Middle Ages, every man was tried according to the laws of his own ethnicity, whether Roman, Salian or Ripuarian Frank, Frisian, Burgundian, Visigoth, Bavarian etc. A number of separate codes were drawn up specifically to deal with cases between ethnic Romans. These codes differed from the normal ones that covered cases between Germanic peoples, or between Germanic people and Romans. The most notable of these are the Lex Romana Visigothorum or Breviary of Alaric (506), the Lex Romana Curiensis and the Lex Romana Burgundionum.
  • 7.4K
  • 02 Dec 2022
Topic Review
List of R1a Frequency by Population
Haplogroup R1a is one of the major classifications (called clades) of Y-chromosome types found in human male lines. It is widespread all across Eurasia. Many sample studies therefore carry information on the incidence of R1a and/or its subclassifications, in particular the dominant branching line represented by the haplogroups R1a1 and R1a1a. The table below collates information from a number of such sample studies, with incidence frequencies in sample data reported as percentages, along with the associated sample sizes.
  • 7.4K
  • 09 Nov 2022
Topic Review
Conservation-Restoration of Cultural Heritage
The conservation-restoration of cultural heritage focuses on protection and care of tangible cultural heritage, including artworks, architecture, archaeology, and museum collections. Conservation activities include preventive conservation, examination, documentation, research, treatment, and education. This field is closely allied with conservation science, curators and registrars.
  • 7.4K
  • 30 Nov 2022
Topic Review
Copper Heap Leaching
Heap leaching is a firm extractive metallurgical technology facilitating the economical processing of different kinds of low-grade ores that are otherwise not exploited.
  • 7.4K
  • 13 Oct 2021
Topic Review
System Theory of Corporate Sustainability
In response to the prevailing sustainability problems that are difficult to solve since they are characterized by complex interdependencies, and the effort to solve one aspect of a sustainability problem may lead to other problems, an interim, system-based theory of corporate sustainability to fill in significant gaps in the corporate sustainability field is developed. The full-blown theory helps the researchers to comprehend, describe and predict situations, behavioral actions and/or context. It guides the researchers to either go against orthodoxy or to continue with it to enrich the current knowledge domain.
  • 7.4K
  • 07 Dec 2022
Topic Review
Vacuum State
In quantum field theory, the quantum vacuum state (also called the quantum vacuum or vacuum state) is the quantum state with the lowest possible energy. Generally, it contains no physical particles. Zero-point field is sometimes used as a synonym for the vacuum state of an individual quantized field. According to present-day understanding of what is called the vacuum state or the quantum vacuum, it is "by no means a simple empty space". According to quantum mechanics, the vacuum state is not truly empty but instead contains fleeting electromagnetic waves and particles that pop into and out of existence. The QED vacuum of quantum electrodynamics (or QED) was the first vacuum of quantum field theory to be developed. QED originated in the 1930s, and in the late 1940s and early 1950s it was reformulated by Feynman, Tomonaga and Schwinger, who jointly received the Nobel prize for this work in 1965. Today the electromagnetic interactions and the weak interactions are unified (at very high energies only) in the theory of the electroweak interaction. The Standard Model is a generalization of the QED work to include all the known elementary particles and their interactions (except gravity). Quantum chromodynamics (or QCD) is the portion of the Standard Model that deals with strong interactions, and QCD vacuum is the vacuum of quantum chromodynamics. It is the object of study in the Large Hadron Collider and the Relativistic Heavy Ion Collider, and is related to the so-called vacuum structure of strong interactions.
  • 7.4K
  • 17 Oct 2022
Topic Review
May 22: 1960 Great Chilean Earthquake
Great Chilean Earthquake (1960) is the most powerful earthquake ever recorded, occurring on May 22, 1960, with a magnitude of 9.5–9.6. Originating off the coast of southern Chile, it caused widespread destruction, significant loss of life, and a massive tsunami that affected countries across the Pacific Ocean. The event led to advancements in seismology, tsunami warning systems, and disaster preparedness.
  • 7.4K
  • 21 May 2025
Topic Review
Conifers Phytochemicals
The phytochemical constituents present in conifer extracts are nontoxic at therapeutic levels, with polyphenolic compounds having significant biological activities. Stilbenes, terpenes, alkaloids, lignins and flavanoids, such as quercetin, rutin, resveratrol, and the compounds PYC and enzogenol, are the phytochemical components of conifer extracts reported to have sedative, antidiabetic, anticancer and anesthetic effects. In addition, phytochemicals present in conifer extracts assist in the regulation of glucose and lipid metabolism, insulin secretion, stimulating β cells, the NF-kB signaling pathway, the inhibition of gluconeogenic enzymes, ROS protective action as well as targeting and modulating cytokines which affect neuron cells and reduce oxidative stress.
  • 7.4K
  • 01 Jun 2021
Topic Review Peer Reviewed
Automobile Tires’ High-Carbon Steel Wire
It is a well-known fact that to manufacture an automobile tire more than 200 different materials are used, including high-carbon steel wire. In order to withstand the affecting forces, the tire tread is reinforced with steel wire or other products such as ropes or strands. These ropes are called steel cord. Steel cord can be of different constructions. To ensure a good adhesive bond between the rubber of the tire and the steel cord, the cord is either brass-plated or bronzed. The reason brass or bronze is used is because copper, which is a part of these alloys, makes a high-strength chemical composition with sulfur in rubber. For steel cord, the high carbon steel is usually used at 0.70–0.95% C. This amount of carbon ensures the high strength of the steel cord. This kind of high-quality, unalloyed steel has a pearlitic structure which is designed for multi-pass drawing. To ensure the specified technical characteristics, modern metal reinforcing materials for automobile tires, metal cord and bead wire, must withstand, first of all, a high breaking load with a minimum running meter weight. At present, reinforcing materials of the strength range 2800–3200 MPa are increasingly used, the manufacture of which requires high-strength wire. The production of such wire requires the use of a workpiece with high carbon content, changing the drawing regimes, patenting, and other operations. At the same time, it is necessary to achieve a reduction in the cost of wire manufacturing. In this context, the development and implementation of competitive processes for the manufacture of high-quality, high-strength wire as a reinforcing material for automobile tires is an urgent task.
  • 7.4K
  • 13 Apr 2022
Topic Review
E-Book
An electronic book, also known as an e-book or eBook, is a book publication made available in digital form, consisting of text, images, or both, readable on the flat-panel display of computers or other electronic devices. Although sometimes defined as "an electronic version of a printed book", some e-books exist without a printed equivalent. E-books can be read on dedicated e-reader devices, but also on any computer device that features a controllable viewing screen, including desktop computers, laptops, tablets and smartphones. In the 2000s, there was a trend of print and e-book sales moving to the Internet, where readers buy traditional paper books and e-books on websites using e-commerce systems. With print books, readers are increasingly browsing through images of the covers of books on publisher or bookstore websites and selecting and ordering titles online; the paper books are then delivered to the reader by mail or another delivery service. With e-books, users can browse through titles online, and then when they select and order titles, the e-book can be sent to them online or the user can download the e-book. By the early 2010s, e-books had begun to overtake hardcover by overall publication figures in the U.S. The main reasons for people buying e-books are possibly lower prices, increased comfort (as they can buy from home or on the go with mobile devices) and a larger selection of titles. With e-books, "[e]lectronic bookmarks make referencing easier, and e-book readers may allow the user to annotate pages." "Although fiction and non-fiction books come in e-book formats, technical material is especially suited for e-book delivery because it can be [electronically] searched" for keywords. In addition, for programming books, code examples can be copied. The amount of e-book reading is increasing in the U.S.; by 2014, 28% of adults had read an e-book, compared to 23% in 2013. This is increasing, because by 2014 50% of American adults had an e-reader or a tablet, compared to 30% owning such devices in 2013.
  • 7.4K
  • 30 Sep 2022
Topic Review
Dhyāna in Buddhism
In the oldest texts of Buddhism, dhyāna (Sanskrit) or jhāna (Pāḷi) is the training of the mind, commonly translated as meditation, to withdraw the mind from the automatic responses to sense-impressions, and leading to a "state of perfect equanimity and awareness (upekkhā-sati-parisuddhi)." Dhyāna may have been the core practice of pre-sectarian Buddhism, in combination with several related practices which together lead to perfected mindfulness and detachment, and are fully realized with the practice of dhyana. In the later commentarial tradition, which has survived in present-day Theravāda, dhyāna is equated with "concentration," a state of one-pointed absorption in which there is a diminished awareness of the surroundings. In the contemporary Theravāda-based Vipassana movement, this absorbed state of mind is regarded as unnecessary and even non-beneficial for awakening, which has to be reached by mindfulness of the body and vipassanā (insight into impermanence). Since the 1980s, scholars and practitioners have started to question this equation, arguing for a more comprehensive and integrated understanding and approach, based on the oldest descriptions of dhyāna in the suttas. In Chán and Zen, the names of which Buddhist traditions are the Chinese and Japanese pronunciations, respectively, of dhyāna, dhyāna is the central practice, which is ultimately based on Sarvastivāda meditation practices, and has been transmitted since the beginning of the Common Era.
  • 7.4K
  • 11 Oct 2022
Topic Review
NASDAQ-100
The NASDAQ-100 (^NDX) is a stock market index made up of 103 equity securities issued by 100 of the largest non-financial companies listed on the Nasdaq stock market. It is a modified capitalization-weighted index. The stocks' weights in the index are based on their market capitalizations, with certain rules capping the influence of the largest components. It is based on exchange, and it does not have any financial companies. The financial companies were put in a separate index, the NASDAQ Financial-100.
  • 7.4K
  • 19 Oct 2022
Topic Review
Electromagnetic Aircraft Launch System
The Electromagnetic Aircraft Launch System (EMALS) is a type of aircraft launching system developed by General Atomics for the United States Navy. The system launches carrier-based aircraft by means of a catapult employing a linear induction motor rather than the conventional steam piston. EMALS was first installed on the United States Navy's Gerald R. Ford-class aircraft carrier, USS Gerald R. Ford. Its main advantage is that it accelerates aircraft more smoothly, putting less stress on their airframes. Compared to steam catapults, the EMALS also weighs less, is expected to cost less and require less maintenance, and can launch both heavier and lighter aircraft than a steam piston-driven system. It also reduces the carrier's requirement of fresh water, thus reducing the demand for energy-intensive desalination. China is reportedly developing a similar system which is expected to be used on China's Type 003 aircraft carriers.
  • 7.4K
  • 21 Nov 2022
Topic Review
Common Factors Theory
Common factors theory, a theory guiding some research in clinical psychology and counseling psychology, proposes that different approaches and evidence-based practices in psychotherapy and counseling share common factors that account for much of the effectiveness of a psychological treatment. This is in contrast to the view that the effectiveness of psychotherapy and counseling is best explained by specific or unique factors (notably, particular methods or procedures) that are suited to treatment of particular problems. According to one review, "it is widely recognized that the debate between common and unique factors in psychotherapy represents a false dichotomy, and these factors must be integrated to maximize effectiveness". In other words, "therapists must engage in specific forms of therapy for common factors to have a medium through which to operate". Common factors is one route by which psychotherapy researchers have attempted to integrate psychotherapies.
  • 7.4K
  • 08 Nov 2022
Topic Review
Machine Learning Techniques in Cybersecurity
Machine learning is of rising importance in cybersecurity. The primary objective of applying machine learning in cybersecurity is to make the process of malware detection more actionable, scalable and effective than traditional approaches, which require human intervention. The cybersecurity domain involves machine learning challenges that require efficient methodical and theoretical handling. Several machine learning and statistical methods, such as deep learning, support vector machines and Bayesian classification, among others, have proven effective in mitigating cyber-attacks. The detection of hidden trends and insights from network data and building of a corresponding data-driven machine learning model to prevent these attacks is vital to design intelligent security systems.
  • 7.4K
  • 01 Aug 2022
Topic Review
Ti Nitrides and Ti Silicides
The diffusion of nitrogen into TiSi2 films of low electrical resistivity, deposited on complementary metal oxyde semiconductor (CMOS) and Schottky diodes components increases their performances. TiN acts as a good diffusion barrier, gate material, Schottky barrier contact...Both TiSi2 and TiN are synthesized in Ti films coated on Si wafers and processed in an expanding microwave plasma producing nitrogen species such as NHx...This process promotes the chemical reactions at the surface of the metal. The growth of both compounds give rise to two competing processes which are thermodynamically and kinetically controlled. Ti films, 250 nm thick, processed at 600°C for  30 min, only consist of TiSi2 crystallites and TiN of amorphous structure. TiN crystallizes at 800°C and grows at the expense of TiSi2 according to thermodynamic data. 
  • 7.4K
  • 30 Oct 2020
Topic Review
Indane-1,3-Dione: From Synthetic Strategies to Applications
Indane-1,3-dione is a versatile building block used in numerous applications ranging from biosensing, bioactivity, bioimaging to electronics or photopolymerization. Indane-1-3-dione is among one of the most privileged scaffolds in chemistry, as the derivatives of this structure can find applications in various research fields ranging from medicinal chemistry, organic electronics, photopolymerization, to optical sensing and non-linear optical (NLO) applications. 
  • 7.4K
  • 29 Sep 2022
Topic Review
List of Largest Stars
Below is a list of the largest stars currently known, ordered by radius. The unit of measurement used is the radius of the Sun (approximately 695,700 km; 432,300 mi). The angular diameters of stars can be measured directly using stellar interferometry. Other methods can use lunar occultations or from eclipsing binaries, which can be used to test indirect methods of finding stellar radii. Only a few useful supergiant stars can be occulted by the Moon, including Antares A (Alpha Scorpii A). Examples of eclipsing binaries are Epsilon Aurigae (Almaaz), VV Cephei, and V766 Centauri (HR 5171). Angular diameter measurements can be inconsistent because the boundary of the very tenuous atmosphere (opacity) differs depending on the wavelength of light in which the star is observed. Uncertainties remain with the membership and order of the list, especially when deriving various parameters used in calculations, such as stellar luminosity and effective temperature. Often stellar radii can only be expressed as an average or be within a large range of values. Values for stellar radii vary significantly in different sources and for different observation methods. All the sizes stated in this list have various inaccuracies and may be disputed. This list is still a work in progress and various parameters are extremely disputed.
  • 7.4K
  • 21 Nov 2022
Topic Review
Dhunge Dhara
A dhunge dhara (Nepali:ढुङ्गे धारा Listen (help·info)) or hiti (Newari) is a traditional stone drinking fountain found in Nepal. It is an intricately carved stone waterway through which water flows uninterrupted from underground sources. Dhunge dharas are part of a comprehensive drinking water supply system, commissioned by various rulers of Ancient and Medieval Nepal. The system is supported by numerous ponds and canals that form an elaborate network of water bodies, created as a water resource during the dry season and to help alleviate the water pressure caused by the monsoon rains. After the introduction of modern, piped water systems, starting in the late 19th century, this old system has fallen into disrepair and some parts of it are lost forever. Nevertheless, many people of Nepal still rely on the old hitis on a daily basis.
  • 7.4K
  • 21 Oct 2022
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