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The Endochronic Properties Of Resublimated Thiotimoline
Thiotimoline is a fictitious chemical compound conceived by American biochemist and science fiction author Isaac Asimov. It was first described in a spoof scientific paper titled "The Endochronic Properties of Resublimated Thiotimoline" in 1948. The major peculiarity of the chemical is its "endochronicity": it starts dissolving before it makes contact with water. Asimov went on to write three additional short stories, each describing different properties or uses of thiotimoline. Chemical properties In Asimov's writings the endochronicity of thiotimoline is explained by the fact that in the thiotimoline molecule, there is at least one carbon atom such that, while two of the carbon's four chemical bonds lie in normal space and time, one of the bonds projects into the future and another into the past. Thiotimoline is derived from the bark of the (fictitious) shrub ''Rosacea karlsbadensis rufo'', and the thiotimoline molecule includes at least fourteen hydroxy groups, two ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
WikiProject Novels
A WikiProject, or Wikiproject, is a Wikimedia movement affinity group for contributors with shared goals. WikiProjects are prevalent within the largest wiki, Wikipedia, and exist to varying degrees within sister projects such as Wiktionary, Wikiquote, Wikidata, and Wikisource. They also exist in different languages, and translation of articles is a form of their collaboration. During the COVID-19 pandemic, CBS News noted the role of Wikipedia's WikiProject Medicine in maintaining the accuracy of articles related to the disease. Another WikiProject that has drawn attention is WikiProject Women Scientists, which was profiled by '' Smithsonian'' for its efforts to improve coverage of women scientists which the profile noted had "helped increase the number of female scientists on Wikipedia from around 1,600 to over 5,000". On Wikipedia Some Wikipedia WikiProjects are substantial enough to engage in cooperative activities with outside organizations relevant to the field at issue. For e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spacetime
In physics, spacetime is a mathematical model that combines the three dimensions of space and one dimension of time into a single four-dimensional manifold. Spacetime diagrams can be used to visualize relativistic effects, such as why different observers perceive differently where and when events occur. Until the 20th century, it was assumed that the three-dimensional geometry of the universe (its spatial expression in terms of coordinates, distances, and directions) was independent of one-dimensional time. The physicist Albert Einstein helped develop the idea of spacetime as part of his theory of relativity. Prior to his pioneering work, scientists had two separate theories to explain physical phenomena: Isaac Newton's laws of physics described the motion of massive objects, while James Clerk Maxwell's electromagnetic models explained the properties of light. However, in 1905, Einstein based a work on special relativity on two postulates: * The laws of physics are invariant ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Only A Trillion
''Only a Trillion'' is a collection of ten science essays and three scientific spoof articles by Isaac Asimov. It was the first collection of science essays published by Asimov. It was first published by Abelard-Schuman in 1957. A paperback edition published by Ace Books in 1976 included updates of outdated material (re-issued in 1980). The book was also published under the title ''Marvels of Science'' by Collier Books in 1962. The title refers to the number of atoms of astatine-215 in the top 10 miles of the Earth's crust of the North and South American continents – only a trillion. Contents # The Atoms That Vanish (first published in ''Change!'', 1957) # The Explosions Within Us (original article) # Hemoglobin and the Universe (first published in ''Astounding Science Fiction'', Feb. 1955) # Victory on Paper (first published in ''Astounding'', Sept. 1955) # The Abnormality of Being Normal (first published in ''Astounding'', May 1956) # Planets Have an Air About Them (first publi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dissociative Identity Disorder
Dissociative identity disorder (DID), better known as multiple personality disorder or multiple personality syndrome, is a mental disorder characterized by the presence of at least two distinct and relatively enduring personality states. The disorder is accompanied by memory gaps more severe than could be explained by ordinary forgetfulness. The personality states alternately show in a person's behavior; however, presentations of the disorder vary. Other conditions that often occur in people with DID include post-traumatic stress disorder, personality disorders (especially borderline and avoidant), depression, substance use disorders, conversion disorder, somatic symptom disorder, eating disorders, obsessive–compulsive disorder, and sleep disorders. Self-harm, non-epileptic seizures, flashbacks with amnesia for content of flashbacks, anxiety disorders, and suicidality are also common. Overview The following three subsections give brief overviews of the proposed cause of d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemical Bond
A chemical bond is a lasting attraction between atoms or ions that enables the formation of molecules and crystals. The bond may result from the electrostatic force between oppositely charged ions as in ionic bonds, or through the sharing of electrons as in covalent bonds. The strength of chemical bonds varies considerably; there are "strong bonds" or "primary bonds" such as covalent, ionic and metallic bonds, and "weak bonds" or "secondary bonds" such as dipole–dipole interactions, the London dispersion force and hydrogen bonding. Strong chemical bonding arises from the sharing or transfer of electrons between the participating atoms. Since opposite electric charges attract, the negatively charged electrons surrounding the nucleus and the positively charged protons within a nucleus attract each other. An electron positioned between two nuclei will be attracted to both of them, and the nuclei will be attracted toward electrons in this position. This attraction constitu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
New York Public Library
The New York Public Library (NYPL) is a public library system in New York City. With nearly 53 million items and 92 locations, the New York Public Library is the second largest public library in the United States (behind the Library of Congress) and the fourth largest in the world. It is a private, non-governmental, independently managed, nonprofit corporation operating with both private and public financing. The library has branches in the boroughs of the Bronx, Manhattan, and Staten Island and affiliations with academic and professional libraries in the New York metropolitan area. The city's other two boroughs, Brooklyn and Queens, are not served by the New York Public Library system, but rather by their respective borough library systems: the Brooklyn Public Library and the Queens Public Library. The branch libraries are open to the general public and consist of circulating libraries. The New York Public Library also has four research libraries, which are also open to the ge ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Columbia University
Columbia University (also known as Columbia, and officially as Columbia University in the City of New York) is a private research university in New York City. Established in 1754 as King's College on the grounds of Trinity Church in Manhattan, Columbia is the oldest institution of higher education in New York and the fifth-oldest institution of higher learning in the United States. It is one of nine colonial colleges founded prior to the Declaration of Independence. It is a member of the Ivy League. Columbia is ranked among the top universities in the world. Columbia was established by royal charter under George II of Great Britain. It was renamed Columbia College in 1784 following the American Revolution, and in 1787 was placed under a private board of trustees headed by former students Alexander Hamilton and John Jay. In 1896, the campus was moved to its current location in Morningside Heights and renamed Columbia University. Columbia scientists and scholars have ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
John W
John is a common English name and surname: * John (given name) * John (surname) John may also refer to: New Testament Works * Gospel of John, a title often shortened to John * First Epistle of John, often shortened to 1 John * Second Epistle of John, often shortened to 2 John * Third Epistle of John, often shortened to 3 John People * John the Baptist (died c. AD 30), regarded as a prophet and the forerunner of Jesus Christ * John the Apostle (lived c. AD 30), one of the twelve apostles of Jesus * John the Evangelist, assigned author of the Fourth Gospel, once identified with the Apostle * John of Patmos, also known as John the Divine or John the Revelator, the author of the Book of Revelation, once identified with the Apostle * John the Presbyter, a figure either identified with or distinguished from the Apostle, the Evangelist and John of Patmos Other people with the given name Religious figures * John, father of Andrew the Apostle and Saint Peter * Pope Jo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Catechol
Catechol ( or ), also known as pyrocatechol or 1,2-dihydroxybenzene, is a toxic organic compound with the molecular formula . It is the ''ortho'' isomer of the three isomeric benzenediols. This colorless compound occurs naturally in trace amounts. It was first discovered by destructive distillation of the plant extract catechin. About 20,000 tonnes of catechol are now synthetically produced annually as a commodity organic chemical, mainly as a precursor to pesticides, flavors, and fragrances. Catechol occurs as feathery white crystals that are very rapidly soluble in water. Isolation and synthesis Catechol was first isolated in 1839 by Edgar Hugo Emil Reinsch (1809–1884) by distilling it from the solid tannic preparation catechin, which is the residuum of catechu, the boiled or concentrated juice of ''Mimosa catechu'' (''Acacia catechu''). Upon heating catechin above its decomposition point, a substance that Reinsch first named ''Brenz-Katechusäure'' (burned catechu acid) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aromatic Hydrocarbon
Aromatic compounds, also known as "mono- and polycyclic aromatic hydrocarbons", are organic compounds containing one or more aromatic rings. The parent member of aromatic compounds is benzene. The word "aromatic" originates from the past grouping of molecules based on smell, before their general chemical properties are understood. The current definition of aromatic compounds does not have any relation with their smell. Heteroarenes are closely related, since at least one carbon atom of CH group is replaced by one of the heteroatoms oxygen, nitrogen, or sulfur. Examples of non-benzene compounds with aromatic properties are furan, a heterocyclic compound with a five-membered ring that includes a single oxygen atom, and pyridine, a heterocyclic compound with a six-membered ring containing one nitrogen atom. Hydrocarbons without an aromatic ring are called aliphatic. Benzene ring model Benzene, C6H6, is the least complex aromatic hydrocarbon, and it was the first one named as such ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrocarbon
In organic chemistry, a hydrocarbon is an organic compound consisting entirely of hydrogen and carbon. Hydrocarbons are examples of group 14 hydrides. Hydrocarbons are generally colourless and hydrophobic, and their odors are usually weak or exemplified by the odors of gasoline and lighter fluid. They occur in a diverse range of molecular structures and phases: they can be gases (such as methane and propane), liquids (such as hexane and benzene), low melting solids (such as paraffin wax and naphthalene) or polymers (such as polyethylene and polystyrene). In the fossil fuel industries, ''hydrocarbon'' refers to the naturally occurring petroleum, natural gas and coal, and to their hydrocarbon derivatives and purified forms. Combustion of hydrocarbons is the main source of the world's energy. Petroleum is the dominant raw-material source for organic commodity chemicals such as solvents and polymers. Most anthropogenic (human-generated) emissions of greenhouse gases are carbon di ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nitro Compound
In organic chemistry, nitro compounds are organic compounds that contain one or more nitro functional groups (). The nitro group is one of the most common explosophores (functional group that makes a compound explosive) used globally. The nitro group is also strongly electron-withdrawing. Because of this property, bonds alpha (adjacent) to the nitro group can be acidic. For similar reasons, the presence of nitro groups in aromatic compounds retards electrophilic aromatic substitution but facilitates nucleophilic aromatic substitution. Nitro groups are rarely found in nature. They are almost invariably produced by nitration reactions starting with nitric acid. Synthesis Preparation of aromatic nitro compounds Aromatic nitro compounds are typically synthesized by nitration. Nitration is achieved using a mixture of nitric acid and sulfuric acid, which produce the nitronium ion (), which is the electrophile: + The nitration product produced on the la ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
