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Topic Review
Unbiunium
Check temperatures Ubu: no input for C, K, F. Check temperatures Ubu: no input for C, K, F. Unbiunium, also known as eka-actinium or simply element 121, is the hypothetical chemical element with symbol Ubu and atomic number 121. Unbiunium and Ubu are the temporary systematic IUPAC name and symbol respectively, until a permanent name is decided upon. In the periodic table of the elements, it is expected to be the first of the superactinides, and the third element in the eighth period: analogously to lanthanum and actinium, it could be considered the fifth member of group 3 and the first member of the fifth-row transition metals. It has attracted attention because of some predictions that it may be in the island of stability, although newer calculations expect the island to actually occur at a slightly lower atomic number, closer to copernicium and flerovium. Unbiunium has not yet been synthesized. Nevertheless, because it is only three elements away from the heaviest known element, oganesson (element 118), its synthesis may come in the near future; it is expected to be one of the last few reachable elements with current technology, and the limit may be anywhere between element 120 and 124. It will also likely be far more difficult to synthesize than the elements known so far up to 118, and still more difficult than elements 119 and 120. The team at RIKEN in Japan has plans to attempt the synthesis of element 121 in the future after its attempts on elements 119 and 120. The position of unbiunium in the periodic table suggests that it would have similar properties to its lighter congeners, scandium, yttrium, lanthanum, and actinium; however, relativistic effects may cause some of its properties to differ from those expected from a straight application of periodic trends. For example, unbiunium is expected to have a s2p valence electron configuration instead of the s2d of its lighter congeners in group 3, but this is not expected to significantly affect its chemistry, which is predicted to be that of a normal group 3 element; it would on the other hand significantly lower its first ionisation energy beyond what would be expected from periodic trends.
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  • 25 Oct 2022
Topic Review
New Energy Vehicles in China
This article will talk about the market of new energy vehicles in China and why the government supports it.The stock of new energy vehicles in China is the world's largest, with cumulative sales of 5.5 million units through December 2020. These figures include passenger cars and heavy-duty commercial vehicles such buses and sanitation trucks, and only accounts for vehicles manufactured in the country. Of these, there were 4.9 million new energy vehicles in use at the end of 2020, accounting for 1.75% of all vehicles in circulation in China. The Chinese government uses the term new energy vehicles (NEVs) to designate plug-in electric vehicles eligible for public subsidies, and includes only battery electric vehicles (BEVs), plug-in hybrid electric vehicles (PHEVs) and fuel cell electric vehicles (FCEV). Sales of new energy vehicles since 2011 passed the 500,000 unit milestone in March 2016, and the 1 million mark in early 2017, both, excluding imports. Cumulative sales of new energy passenger cars achieved the 500,000 unit milestone in September 2016, and 1 million by the end of 2017. Domestically produced passenger cars account for 96% of new energy car sales in China. (As of December 2020), China had the largest stock of highway legal plug-in passenger cars with over 4.5 million units, 42% of the global plug-in car fleet in use. China also dominates the plug-in light commercial vehicle and electric bus deployment, with its stock reaching over 500,000 buses in 2019, 98% of the global stock, and 247,500 electric light commercial vehicles, 65% of the global fleet. In addition, the country also leads sales of medium- and heavy duty electric trucks, with over 12,000 trucks sold, and nearly all battery electric. China has been the world's best-selling plug-in electric passenger car market for five years running, from 2015 to 2019, with annual sales rising from more than 207,000 plug-in passenger cars in 2015, to 579,000 in 2017, and just over  million units both in 2018 and 2019. A particular feature of the Chinese passenger plug-in market is the dominance of small entry level vehicles, in 2015 representing 87% of total pure electric car sales, while 96% of total plug-in hybrid car sales were in the compact segment. BYD Auto ended 2015 as the world's best selling manufacturer of highway legal light-duty plug-in electric vehicles, and for a second year running was the world's top selling plug-in car manufacturer with over 100,000 units delivered in 2016. During 2016 BYD became the world's all-time second largest plug-in electric passenger car manufacturer after the Renault-Nissan Alliance. The BYD Qin was the top selling new energy passenger car for two years in a row, 2014 and 2015. The BYD Tang was the best selling plug-in passenger car in 2016. Until December 2016, the Qin ranked as the all-time top selling plug-in electric car in the country with 68,655 units sold since its inception. The BAIC EC-Series all-electric city car was the top selling plug-in car in 2017, and with 78,079 units sold, it also listed as world's top selling plug-in car in 2017. The government's political support for the adoption of electric vehicles has four goals, to create a world-leading industry that would produce jobs and exports; energy security to reduce its oil dependence which comes from the Middle East; to reduce urban air pollution; and to reduce its carbon emissions. In June 2012 the State Council of China published a plan to develop the domestic energy-saving and new energy vehicle industry. The plan set a sales target of 500,000 new energy vehicles by 2015 and 5 million by 2020. As sales of new energy vehicles were slower than expected, in September 2013, the central government introduced a subsidy scheme providing a maximum of US$9,800 toward the purchase of an all-electric passenger vehicle and up to US$81,600 for an electric bus.
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  • 01 Dec 2022
Topic Review
Idealism in International Relations
Idealism in foreign policy holds that a state should make its internal political philosophy the goal of its foreign policy. For example, an idealist might believe that ending poverty at home should be coupled with tackling poverty abroad. U.S. President Woodrow Wilson was an early advocate of idealism. Wilson's idealism was a precursor to liberal international relations theory, which would arise amongst the "institution-builders" after World War II. It particularly emphasized the ideal of American exceptionalism. More generally, Michael W. Doyle describes idealism as based on the belief that other nations' stated good intentions can be relied on, whereas Realism holds that good intentions are in the long run subject to the security dilemma described by John H. Herz. Hedley Bull wrote: By the 'idealists' we have in mind writers such as Sir Alfred Zimmern, S. H. Bailey, Philip Noel-Baker, and David Mitrany in the United Kingdom, and James T. Shotwell, Pitman Potter, and Parker T. Moon in the United States. ... The distinctive characteristic of these writers was their belief in progress: the belief, in particular, that the system of international relations that had given rise to the First World War was capable of being transformed into a fundamentally more peaceful and just world order; that under the impact of the awakening of democracy, the growth of 'the international mind', the development of the League of Nations, the good works of men of peace or the enlightenment spread by their own teaching, it was in fact being transformed; and that their responsibility as students of international relations was to assist this march of progress to overcome the ignorance, the prejudices, the ill-will, and the sinister interests that stood in its way.
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  • 09 Oct 2022
Topic Review
Parallelism Measurement Methods
At present, the parallelism error was evaluated by contact probe, laser interferometer, and  autocollimator, etc. Moreover, it can also be divided into contact method and non-contact method based on the measurement principle.
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  • 29 Oct 2020
Topic Review
Old Aramaic Language
Old Aramaic refers to the earliest stage of the Aramaic language, considered to give way to Middle Aramaic by the 3rd century (a conventional date is the rise of the Sasanian Empire in 224 AD). Emerging as the language of the city-states of the Arameans in the Levant in the Early Iron Age, Old Aramaic was adopted as a lingua franca, and in this role was inherited for official use by the Achaemenid Empire during classical antiquity. After the fall of the Achaemenid Empire, local vernaculars became increasingly prominent, fanning the divergence of an Aramaic dialect continuum and the development of differing written standards.
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  • 21 Oct 2022
Biography
Bertrand Russell
Bertrand Arthur William Russell, 3rd Earl Russell OM FRS[1] (18 May 1872 – 2 February 1970) was a British polymath. As an academic, he worked in philosophy, mathematics, and logic. His work has had a considerable influence on mathematics, logic, set theory, linguistics, artificial intelligence, cognitive science, computer science, and various areas of analytic philosophy, especially philosophy
  • 9.4K
  • 18 Nov 2022
Topic Review
Risk-Acceptance Criteria
The utilization of risk acceptance criteria (RAC) can help a business to judge whether the risk level concerning any process involved in its working environment is acceptable or not, especially when the risk has a significant societal impact.
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  • 28 Mar 2022
Topic Review
Light cured dental composite resins
The photoinduced polymerization of monomers is currently an essential tool in various industries. The photopolymerization process plays an increasingly important role in biomedical applications. It is especially used in the production of dental composites. It also exhibits unique properties, such as a short time of polymerization of composites (up to a few seconds), low e tes with their limitations and disadvantages. nergy consumption, and spatial resolution (polymerization only in irradiated areas). This entry describes a short overview of the history and classification of different typical monomers and photoinitiating systems such as bimolecular photoinitiator system containing camphorquinone and aromatic amine, 1-phenyl-1,2-propanedione, phosphine derivatives, germanium derivatives, hexaarylbiimidazole derivatives, silane-based derivatives and thioxanthone derivatives used in the production of dental composites with their limitations and disadvantages.
  • 9.4K
  • 07 Oct 2020
Topic Review
Mental Distress
Mental distress (or psychological distress) is a term used, by some mental health practitioners and users of mental health services, to describe a range of symptoms and experiences of a person's internal life that are commonly held to be troubling, confusing or out of the ordinary. Mental distress can potentially lead to a change of behavior, affect a person's emotions in a negative way, and affect their relationships with the people around them. Certain traumatic life experiences such as: bereavement, stress, lack of sleep, use of drugs or alcohol, assault, abuse or accidents can induce mental distress. This may be something which resolves without further medical intervention, though people who endure such symptoms longer term are more likely to be diagnosed with mental illness. This definition is not without controversy as some mental health practitioners would use the terms mental distress and mental illness interchangeably. Some users of mental health services prefer the term mental distress in describing their experience as they feel it better captures that sense of the unique and personal nature of their experience, while also making it easier to relate to, since everyone experiences distress at different times. The term also fits better with the social model of disability.
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  • 06 Oct 2022
Topic Review
Luminiferous Aether
Luminiferous aether or ether ("luminiferous", meaning "light-bearing") was the postulated medium for the propagation of light. It was invoked to explain the ability of the apparently wave-based light to propagate through empty space, something that waves should not be able to do. The assumption of a spatial plenum of luminiferous aether, rather than a spatial vacuum, provided the theoretical medium that was required by wave theories of light. The aether hypothesis was the topic of considerable debate throughout its history, as it required the existence of an invisible and infinite material with no interaction with physical objects. As the nature of light was explored, especially in the 19th century, the physical qualities required of an aether became increasingly contradictory. By the late 1800s, the existence of the aether was being questioned, although there was no physical theory to replace it. The negative outcome of the Michelson–Morley experiment (1887) suggested that the aether did not exist, a finding that was confirmed in subsequent experiments through the 1920s. This led to considerable theoretical work to explain the propagation of light without an aether. A major breakthrough was the theory of relativity, which could explain why the experiment failed to see aether, but was more broadly interpreted to suggest that it was not needed. The Michelson-Morley experiment, along with the blackbody radiator and photoelectric effect, was a key experiment in the development of modern physics, which includes both relativity and quantum theory, the latter of which explains the particle-like nature of light.
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  • 17 Oct 2022
Topic Review
Different Composting Technologies
Organic waste management is a major global challenge. It accounts for a significant portion of waste that ends up in landfills, where it gradually decomposes and emits methane, a harmful greenhouse gas. Composting is the most preferred method for managing organic waste, as it applies to the masses, may not require significant areas, and of course, is capable of reducing the rate of the production of waste, while at the same time, producing valuable by-products, in the form of compost with potentially reducing the amount of greenhouse gas emissions, if done properly.
  • 9.3K
  • 23 Sep 2022
Topic Review
Security and Privacy in Cloud Computing
Advances in the usage of information and communication technologies (ICT) has given rise to the popularity and success of cloud computing. Cloud computing offers advantages and opportunities for business users to migrate and leverage the scalability of the pay-as-you-go price model. However, outsourcing information and business applications to the cloud or a third party raises security and privacy concerns, which have become critical in adopting cloud implementation and services. Researchers and affected organisations have proposed different security approaches in the literature to tackle the present security flaws. The literature also provides an extensive review of security and privacy issues in cloud computing. Unfortunately, the works provided in the literature lack the flexibility in mitigating multiple threats without conflicting with cloud security objectives. The literature has further focused on only highlighting security and privacy issues without providing adequate technical approaches to mitigate such security and privacy threats. Conversely, studies that offer technical solutions to security threats have failed to explain how such security threats exist.
  • 9.3K
  • 11 Jan 2022
Topic Review
History of Taoism
The history of Taoism stretches throughout Chinese history. Originating in prehistoric China, it has exerted a powerful influence over Chinese culture throughout the ages. Taoism evolved in response to changing times, with its doctrine and associated practices being revised and refined. The acceptance of Taoism by the ruling class has waxed and waned, alternately enjoying periods of favor and rejection. Most recently, Taoism has emerged from a period of suppression and is undergoing a revival in China. Laozi is traditionally regarded as the founder of Taoist religion and is closely associated in this context with "original", or "primordial", Taoism. Whether he actually existed is disputed, however, the work attributed to him - the Daodejing - is dated to the 4th or 3rd century BC. However, Taoism clearly predates Laozi (Lao Tzu) as he refers to "The Tao masters of antiquity" in Chapter 15 of the Daodejing (Tao Te Ching). Moreover, the Yellow Emperor, Huangdi (2697–2597 BCE) Is often associated with origin of the Tao. Sinologist Isabelle Robinet identifies four components in the emergence of Taoism: Some elements of Taoism may be traced to prehistoric folk religions in China that later coalesced into a Taoist tradition. In particular, many Taoist practices drew from the Warring-States-era phenomena of the Wu (shaman) (connected to the "shamanism" of Southern China) and the Fangshi (which probably derived from the "archivist-soothsayers of antiquity, one of whom supposedly was Laozi himself"), even though later Taoists insisted that this was not the case. Both terms were used to designate individuals dedicated to "... magic, medicine, divination,... methods of longevity and to ecstatic wanderings" as well as exorcism; in the case of the wu, "shamans" or "sorcerers" is often used as a translation. The fangshi were philosophically close to the School of Yin-Yang, and relied much on astrological and calendrical speculations in their divinatory activities.
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  • 08 Nov 2022
Topic Review
Huītzilōpōchtli
In Aztec mythology, Huitzilopochtli (Template:Lang-nci-IPA, modern Nahuatl pronunciation (help·info)) is the deity of war, sun, human sacrifice, and the patron of the city of Tenochtitlan. He was also the tribal god of the Mexicas, also known as the Aztecs, of Tenochtitlan. Many in the pantheon of deities of the Aztecs were inclined to have a fondness for a particular aspect of warfare. However, Huitzilopochtli was known as the primary god of war in ancient Mexico. Since he was the patron god of the Mexica, he was credited with both the victories and defeats that the Mexica people had on the battlefield. The people had to make sacrifices to him to protect the Aztec from infinite night. He wielded Xiuhcoatl, the fire serpent, as a weapon, thus also associating Huitzilopochtli with fire. As noted by the Spaniards during their discovery and conquest of the Aztec Empire (wherein they recorded the deity's name as Huichilobos), human sacrifice was common in worship ceremonies, which took place frequently and in numerous temples throughout the region, and when performed they typically sacrificed multiple victims per day at a given temple.
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  • 15 Nov 2022
Topic Review
Harrison Family of Virginia
The Harrison family of Virginia, primarily consisting of two branches, is a notable political family in U.S. history. The family’s origin is in England ; members of one branch immigrated to Virginia before 1633, settled on the James River, and are occasionally referred to as the James River Harrisons. This branch includes successive generations who served in the colonial Virginia legislature, a signer of the Declaration of Independence, and several Virginia Governors. Also notably descended from the James River family were two presidents of the United States, William Henry Harrison and Benjamin Harrison. The family produced as well two mayors of Chicago, and members of the U. S. House of Representatives. The second branch of the Virginia Harrisons descends from an interim chaplain of the Jamestown Colony, who returned to England. The family later immigrated in 1687, first to New England, and then settled in the Shenandoah Valley of Virginia fifty years later. They include the founder of the city of Harrisonburg, and brought forth another of the nation’s presidents, Abraham Lincoln. This branch also includes noted physicians, educators, and local officials.
  • 9.3K
  • 27 Nov 2022
Topic Review
German Gold Mark
Goldmark (officially just Mark, sign: ℳ) was the gold standard-based currency of the German Empire from 1873 to 1914. Papiermark was the Mark after the gold standard was given up in August 1914, and gold and silver coins ceased to circulate.
  • 9.3K
  • 08 Oct 2022
Topic Review
Synesthesia
Synesthesia (American English) or synaesthesia (British English) is a perceptual phenomenon in which stimulation of one sensory or cognitive pathway leads to involuntary experiences in a second sensory or cognitive pathway. People who report a lifelong history of such experiences are known as synesthetes. Awareness of synesthetic perceptions varies from person to person. In one common form of synesthesia, known as grapheme–color synesthesia or color–graphemic synesthesia, letters or numbers are perceived as inherently colored. In spatial-sequence, or number form synesthesia, numbers, months of the year, or days of the week elicit precise locations in space (e.g., 1980 may be "farther away" than 1990), or may appear as a three-dimensional map (clockwise or counterclockwise). Synesthetic associations can occur in any combination and any number of senses or cognitive pathways. Little is known about how synesthesia develops. It has been suggested that synesthesia develops during childhood when children are intensively engaged with abstract concepts for the first time. This hypothesis – referred to as semantic vacuum hypothesis – could explain why the most common forms of synesthesia are grapheme–color, spatial sequence, and number form. These are usually the first abstract concepts that educational systems require children to learn. Difficulties have been recognized in adequately defining synesthesia. Many different phenomena have been included in the term synesthesia, and in many cases the terminology seems to be inaccurate. A more accurate but less common term may be ideasthesia. The earliest recorded case of synesthesia is attributed to the Oxford University academic and philosopher John Locke, who, in 1690, made a report about a blind man who said he experienced the color scarlet when he heard the sound of a trumpet. However, there is disagreement as to whether Locke described an actual instance of synesthesia or was using a metaphor. The first medical account came from German physician Georg Tobias Ludwig Sachs in 1812. The term is from the Ancient Greek σύν syn, 'together', and αἴσθησις aisthēsis, 'sensation'.
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  • 15 Nov 2022
Topic Review
Stilbene Biosynthesis
Stilbenes are a small family of polyphenolic secondary metabolites that can be found in several distantly related plant species. These compounds act as phytoalexins, playing a crucial role in plant defense against phytopathogens, as well as being involved in the adaptation of plants to abiotic environmental factors. Among stilbenes, trans-resveratrol is certainly the most popular and extensively studied for its health properties. However, many other stilbenes, both monomeric and oligomeric, are currently under intensive investigation due to their biological role and bioactivity.
  • 9.3K
  • 14 Jan 2021
Topic Review
Ethnomedicinal Plants
Ethnomedicinal plants have a significant role in the lives of people of rural and tribal areas. Thousands of medicinal plant species are used to treat various diseases, including jaundice, and are considered an important therapeutic resource to minimize these diseases. Jaundice (icterus) is a chronic disease that occurs when the amount of bilirubin in the blood increases.
  • 9.3K
  • 08 Feb 2021
Topic Review
Lotus-Leaf-Inspired Biomimetic Coatings
A universal infrastructural issue is wetting of surfaces; millions of dollars are invested annually for rehabilitation and maintenance of infrastructures including roadways and buildings to fix the damages caused by moisture and frost. The biomimicry of the lotus leaf can provide superhydrophobic surfaces that can repel water droplets, thus reducing the penetration of moisture, which is linked with many deterioration mechanisms in infrastructures, such as steel corrosion, sulfate attack, alkali-aggregate reactions, and freezing and thawing. In cold-region countries, the extent of frost damage due to freezing of moisture in many components of infrastructures will be decreased significantly if water penetration can be minimized. Consequently, it will greatly reduce the maintenance and rehabilitation costs of infrastructures.
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  • 11 Jun 2022
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