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Topic Review
Keto–Enol Tautomerism
In organic chemistry, keto–enol tautomerism refers to a chemical equilibrium between a keto form (a ketone or an aldehyde) and an enol (an alcohol). The keto and enol forms are said to be tautomers of each other. The interconversion of the two forms involves the movement of an alpha hydrogen atom and the reorganisation of bonding electrons; hence, the isomerism qualifies as tautomerism. A compound containing a carbonyl group (C=O) is normally in rapid equilibrium with an enol tautomer, which contains a pair of doubly bonded carbon atoms adjacent to a hydroxyl (−OH) group, C=C-OH. The keto form predominates at equilibrium for most ketones. Nonetheless, the enol form is important for some reactions. The deprotonated intermediate in the interconversion of the two forms, referred to as an enolate anion, is important in carbonyl chemistry, in large part because it is a strong nucleophile. Normally, the keto–enol tautomerization chemical equilibrium is highly thermodynamically driven, and at room temperature the equilibrium heavily favors the formation of the keto form. A classic example for favoring the keto form can be seen in the equilibrium between vinyl alcohol and acetaldehyde (K = [enol]/[keto] ≈ 3 × 10−7). However, it is reported that in the case of vinyl alcohol, formation of a stabilized enol form can be accomplished by controlling the water concentration in the system and utilizing the kinetic favorability of the deuterium-produced kinetic isotope effect (kH+/kD+ = 4.75, kH2O/kD2O = 12). Deuterium stabilization can be accomplished through hydrolysis of a ketene precursor in the presence of a slight stoichiometric excess of heavy water (D2O). Studies show that the tautomerization process is significantly inhibited at ambient temperatures ( kt ≈ 10−6 M/s), and the half-life of the enol form can easily be increased to t1/2 = 42 minutes for first-order hydrolysis kinetics. Another exception is the 1,3-diketones, such as acetylacetone (2,4-pentanedione), which favor the enol form.
  • 6.3K
  • 24 Oct 2022
Topic Review
Personality Test
A personality test is a method of assessing human personality constructs. Most personality assessment instruments (despite being loosely referred to as "personality tests") are in fact introspective (i.e., subjective) self-report questionnaire (Q-data, in terms of LOTS data) measures or reports from life records (L-data) such as rating scales. Attempts to construct actual performance tests of personality have been very limited even though Raymond Cattell with his colleague Frank Warburton compiled a list of over 2000 separate objective tests that could be used in constructing objective personality tests. One exception however, was the Objective-Analytic Test Battery, a performance test designed to quantitatively measure 10 factor-analytically discerned personality trait dimensions. A major problem with both L-data and Q-data methods is that because of item transparency, rating scales and self-report questionnaires are highly susceptible to motivational and response distortion ranging all the way from lack of adequate self-insight (or biased perceptions of others) to downright dissimulation (faking good/faking bad) depending on the reason/motivation for the assessment being undertaken. The first personality assessment measures were developed in the 1920s and were intended to ease the process of personnel selection, particularly in the armed forces. Since these early efforts, a wide variety of personality scales and questionnaires have been developed, including the Minnesota Multiphasic Personality Inventory (MMPI), the Sixteen Personality Factor Questionnaire (16PF), the Comrey Personality Scales (CPS), among many others. Although popular especially among personnel consultants, the Myers–Briggs Type Indicator (MBTI) has numerous psychometric deficiencies. More recently, a number of instruments based on the Five Factor Model of personality have been constructed such as the Revised NEO Personality Inventory. However, the Big Five and related Five Factor Model have been challenged for accounting for less than two-thirds of the known trait variance in the normal personality sphere alone. Estimates of how much the personality assessment industry in the US is worth range anywhere from $2 and $4 billion a year (as of 2013). Personality assessment is used in wide a range of contexts, including individual and relationship counseling, clinical psychology, forensic psychology, school psychology, career counseling, employment testing, occupational health and safety and customer relationship management.
  • 6.3K
  • 13 Oct 2022
Topic Review
Morel Cultivation Industry in China
Morels are one of the most highly prized edible and medicinal mushrooms worldwide. Therefore, historically, there has been a large international interest in their cultivation. Numerous ecological, physiological, genetic, taxonomic, and mycochemical studies have been previously developed. At the beginning of 21th century, China finally achieved artificial cultivation and started a high-scale commercial development in 2012. Due to its international interest, its cultivation scale and area expanded rapidly in this country. However, along with the massive industrial scale, a number of challenges, including the maintenance of steady economic profits, arise. In order to contribute to the solution of these challenges, formal research studying selection, species recognition, strain aging, mating type structure, life cycle, nutrient metabolism, growth and development, and multi-omics has recently been boosted.
  • 6.3K
  • 29 Aug 2023
Topic Review
Internet of Things
The Internet of Things (IoT) refers to a system of interrelated, internet-connected objects that are able to collect and transfer data over a wireless network without human intervention. The term IoT has been considered as an expanding technique applied in various applications and functions, from smart environments and houses to personal healthcare and others [1]. It is described as a smart concept for the internet relating everything to the Internet and data organization and information exchange [2]. The key features required for employing a large-scale IoT are low-cost sensors, highspeed and error-tolerant data communications, smart computations, and numerous applications.
  • 6.3K
  • 26 Oct 2020
Topic Review
6G-IoT Technologies
The advent of 6G-IoT promises a revolutionary leap, integrating AI, expanded coverage, and autonomy in a seamless manner, thereby reshaping industries such as smart agriculture. Presented here are the essential technologies that will make it possible to meet the 6G-IoT requirements.
  • 6.3K
  • 07 Aug 2023
Topic Review
Cardiff
Cardiff (/ˈkɑːrdɪf/ (listen); Welsh: Caerdydd [kairˈdiːð, kɑːɨrˈdɨːð] (listen)) is the capital of Wales, and its largest city. The eleventh-largest city in the United Kingdom , it is Wales's chief commercial centre, the base for most national cultural institutions and Welsh media, and the seat of the National Assembly for Wales. The unitary authority area's 2017 population was estimated to be 362,756. Cardiff is a significant tourist centre and the most popular visitor destination in Wales with 21.3 million visitors in 2017. In 2011, Cardiff was ranked sixth in the world in National Geographic's alternative tourist destinations. Cardiff is the county town of the historic county of Glamorgan (and later South Glamorgan). Cardiff is part of the Eurocities network of the largest European cities. A small town until the early 19th century, its prominence as a major port for the transport of coal following the arrival of industry in the region contributed to its rise as a major city. The Cardiff Built-up Area covers a slightly larger area outside the county boundary and includes the towns of Dinas Powys and Penarth. In 1905, Cardiff was made a city and proclaimed the capital of Wales in 1955. Since the 1980s, Cardiff has seen significant development. A new waterfront area at Cardiff Bay contains the Senedd building, home to the Welsh Assembly and the Wales Millennium Centre arts complex. Current developments include the continuation of the redevelopment of the Cardiff Bay and city centre areas with projects such as the Cardiff International Sports Village, a BBC drama village, and a new business district in the city centre. Sporting venues in the city include the Principality Stadium—the national stadium and the home of the Wales national rugby union team—Sophia Gardens (the home of Glamorgan County Cricket Club), Cardiff City Stadium (the home of Cardiff City football team and the Wales football team), Cardiff International Sports Stadium (the home of Cardiff Amateur Athletic Club), Cardiff Arms Park (the home of Cardiff Blues and Cardiff RFC rugby union teams) and Ice Arena Wales (the home of Cardiff Devils ice hockey team). The city hosted the 1958 British Empire and Commonwealth Games. The city was awarded the title of European City of Sport twice, due to its role in hosting major international sporting events: first in 2009 and again in 2014. The Principality Stadium hosted 11 football matches as part of the 2012 Summer Olympics, including the games' opening event and the men's bronze medal match.
  • 6.3K
  • 18 Oct 2022
Topic Review
Graphical Projection
Graphical projection is a protocol, used in technical drawing, by which an image of a three-dimensional object is projected onto a planar surface without the aid of numerical calculation.
  • 6.3K
  • 07 Nov 2022
Topic Review
Malaysia Waste Management Practices
The three main municipalities of Malaysia, Kuala Lumpur, Penang, and Melaka, were discussed in their actions in household waste management practices and strategies in social, economy, information technology, and governance to achieve success for a better sustainability of the environment.
  • 6.3K
  • 06 Jun 2022
Topic Review
Volkswagen Passat NMS
The 2012 Volkswagen Passat (internally designated Volkswagen New Midsize Sedan, or NMS while under development) is a mid-sized sedan that debuted in January 2011 at the Detroit Auto Show, is manufactured at the Volkswagen Chattanooga Assembly Plant, replaces the Passat B6 in the North American market, and is marketed also in South Korea. At its introduction, the Passat NMS was part of Volkswagen Group's strategy to sell over 800,000 vehicles per year in the North American market. The vehicle was developed by Shanghai Volkswagen Automotive and Volkswagen Passenger Cars, and is partially based on the PQ46 platform used by the European Passat.
  • 6.3K
  • 18 Oct 2022
Topic Review
Modern Stoicism
Modern Stoicism is an intellectual and popular movement that began at the end of the 20th century aimed at reviving the practice of Stoicism. It is not to be confused with neostoicism, an analogous phenomenon in the 17th century. The term "modern Stoicism" covers both the revival of interest in the Stoic philosophy and the philosophical efforts to adjust ancient Stoicism to the language and conceptual framework of the present. The rise of modern Stoicism has received attention in the international media since around November 2012 when the first Annual Stoic Week event was organized.
  • 6.3K
  • 04 Nov 2022
Topic Review
48,XXYY Syndrome
48,XXYY syndrome is a chromosomal condition that causes infertility, developmental and behavioral disorders, and other health problems in males.
  • 6.3K
  • 23 Dec 2020
Topic Review
Classification of the Marine Selective Catalytic Reduction Systems
The marine SCR system is mainly composed of a urea solution injection system, mixer, SCR reactor, measurement system, and soot blowing system. The urea solution injection system is composed of a urea storage tank, urea injection pump, nozzle, valve, and pipeline. Additionally, a static mixer is arranged in the exhaust pipe of the marine SCR system to improve the mixing uniformity of exhaust gas and ammonia gas. 
  • 6.3K
  • 18 May 2022
Topic Review
9K111 Fagot
The 9K111 Fagot (Russian: Фагот; "bassoon") is a second-generation tube-launched SACLOS wire-guided anti-tank missile system of the Soviet Union for use from ground or vehicle mounts. The 9K111 Fagot missile system was developed by the Tula KBP Design Bureau for Instrument Building. "9M111" is the GRAU designation of the missile. Its NATO reporting name is AT-4 Spigot.
  • 6.3K
  • 21 Oct 2022
Topic Review
Energy Resources in Algeria
Algeria is a wealthy country with natural resources, namely, nuclear, renewable, and non-renewable sources. The non-renewable energy sources are considered the lion’s share for energy production (98%). Algeria’s efforts to ensure and strengthen its energy security will take an important step in the coming decades by commissioning new energy infrastructure based on intensive use of water, coal, nuclear, non-renewable, and renewable sources.
  • 6.3K
  • 06 Jul 2022
Topic Review
Plant-Mediated Nanoparticle Synthesis
The green synthesis of nanoparticles(NPs) is gaining attention owing to its facilitation of the development of alternative, sustainable, safer, less toxic and environment-friendly approaches. Thus, green nanotechnology using plant extract opens up new possibilities for the synthesis of novel nanoparticles with the desirable characteristics required for developing biosensors, biomedicine, cosmetics and nano-biotechnology, and in electrochemical, catalytic, antibacterial, electronics, sensing and other applications. 
  • 6.3K
  • 02 Mar 2022
Topic Review
LGBT Social Movements
Lesbian, gay, bisexual, and transgender (LGBT) social movements are social movements that advocate for LGBT people in society. Social movements may focus on equal rights, such as the 2000s movement for same-sex marriage, or they may focus on liberation, as in the gay liberation movement of the 1960s and 1970s. Earlier movements focused on self-help and self-acceptance, such as the homophile movement of the 1950s. Although there is not a primary or an overarching central organization that represents all LGBT people and their interests, numerous LGBT rights organizations are active worldwide. The earliest organizations to support LGBT rights were formed in the early 20th century. A commonly stated goal among these movements is social equality for LGBT people, but there is still denial of full LGBT rights. Some have also focused on building LGBT communities or worked towards liberation for the broader society from biphobia, homophobia, and transphobia. There is a struggle for LGBT rights today. LGBT movements organized today are made up of a wide range of political activism and cultural activity, including lobbying, street marches, social groups, media, art, and research.
  • 6.3K
  • 11 Nov 2022
Topic Review
Intermittent Energy Source
An intermittent energy source is any source of energy that is not continuously available for conversion into electricity and outside direct control because the used primary energy cannot be stored. Intermittent energy sources may be predictable but cannot be dispatched to meet the demand of an electric power system. The use of intermittent sources in an electric power system usually displaces storable primary energy that would otherwise be consumed by other power stations. Another option is to store electricity generated by non-dispatchable energy sources for later use when needed, e.g. in the form of pumped storage, compressed air or in batteries. A third option is the sector coupling e.g. by electric heating for district heating schemes. The use of small amounts of intermittent power has little effect on grid operations. Using larger amounts of intermittent power may require upgrades or even a redesign of the grid infrastructure.
  • 6.3K
  • 26 Oct 2022
Topic Review
Corporate Social Responsibility in Saudi Arabia
In Saudi Arabia, as in the international arena, corporate social responsibility (CSR) is a trending phenomenon that has been transforming and influencing government policies, business strategic management, and societal relationships.
  • 6.3K
  • 13 May 2022
Topic Review
Sex Ratio
The sex ratio is the ratio of males to females in a population. In most sexually reproducing species, the ratio tends to be 1:1. This tendency is explained by Fisher's principle. For various reasons, however, many species deviate from anything like an even sex ratio, either periodically or permanently. Examples include parthenogenic species, periodically mating organisms such as aphids, some eusocial wasps such as Polistes fuscatus and Polistes exclamans, bees, ants, and termites. The human sex ratio is of particular interest to anthropologists and demographers. In human societies, however, sex ratios at birth may be considerably skewed by factors such as the age of mother at birth, and by sex-selective abortion and infanticide. Exposure to pesticides and other environmental contaminants may be a significant contributing factor as well. As of 2014, the global sex ratio at birth is estimated at 107 boys to 100 girls (1,000 boys per 934 girls).
  • 6.3K
  • 19 Oct 2022
Topic Review
Geotourism
Geotourism is a form of nature tourism that provides a more immersive experience by exploring the geological richness of the destination. In their natural form or explored as thermal springs and spas, landscape elements and geological formations offer visitors a richer and more holistic experience.
  • 6.3K
  • 06 Jan 2022
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