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History Of Science And Technology In Japan
This article is about the history of science and technology in modern Japan. Science In the natural sciences, the number of Japanese winners of the Nobel Prize has been second only to the United States in the 21st century, for contributions made in the 20th century. On the list of countries by research and development spending, Japan is third on the list, behind the United States and China. Chemistry Frontier Molecular Orbital Theory In 1952, Kenichi Fukui published a paper in the ''Journal of Chemical Physics'' titled "A molecular theory of reactivity in aromatic hydrocarbons." He later received the 1981 Nobel Prize in Chemistry for his investigations into the mechanisms of chemical reactions, with his prize-winning work focused on the role of frontier orbitals in chemical reactions, specifically that molecules share loosely bonded electrons which occupy the frontier orbitals, that is the Highest Occupied Molecular Orbital (HOMO) and the Lowest Unoccupied Molecular Orbital ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Science And Technology In Japan
Science and technology in Japan has helped fuel the rapid industrial and economic development of the country. Japan has Research and development in Japan, a long history and tradition for research and development, stretching as far back as the Meiji (era), Meiji period. However, science and technology developed rapidly after the Second World War, which has affected the advancement of vehicle technology, consumer electronics, robotics, medical devices, space exploration, and the film industry. Japan's exemplary educational system as well as its higher education institutions help contribute to the country's acceptance for technological innovation and aid engineering talent development. High levels of support for research and development have enabled Japan to produce advances in automotive engines, television display technology, videogames, optical clocks, and many other fields. Japan is also advanced and a global leader in the robotics, natural sciences, aerospace exploration an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Asymmetric Hydrogenation
Asymmetric hydrogenation is a chemical reaction that adds two atoms of hydrogen to a target (substrate) molecule with three-dimensional spatial selectivity. Critically, this selectivity does not come from the target molecule itself, but from other reagents or catalysts present in the reaction. This allows spatial information (what chemists refer to as chirality) to transfer from one molecule to the target, forming the product as a single enantiomer. The chiral information is most commonly contained in a catalyst and, in this case, the information in a single molecule of catalyst may be transferred to many substrate molecules, amplifying the amount of chiral information present. Similar processes occur in nature, where a chiral molecule like an enzyme can catalyse the introduction of a chiral centre to give a product as a single enantiomer, such as amino acids, that a cell needs to function. By imitating this process, chemists can generate many novel synthetic molecules that inte ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hideki Shirakawa
is a Japanese chemist, engineer, and Professor Emeritus at the University of Tsukuba and Zhejiang University. He is best known for his discovery of conductive polymers. He was co-recipient of the 2000 Nobel Prize in Chemistry jointly with Alan MacDiarmid and Alan Heeger. Early life and education Hideki Shirakawa was born in Tokyo, Japan, the second son of a military doctor. He had one elder and one younger brother and sister. Olympic marathoner champion Naoko Takahashi is his second cousin-niece. He lived in Manchukuo and Taiwan during childhood. Around third grade, he moved to Takayama, Gifu, which is the hometown of his mother. Shirakawa graduated from Tokyo Institute of Technology (Tokyo Tech) with a bachelor's degree in chemical engineering in 1961, and his doctorate in 1966. Afterward, he obtained the post of assistant in Chemical Resources Laboratory at Tokyo Tech. Career While employed as an assistant at Tokyo Institute of Technology (Tokyo Tech) in Japan, Sh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protein
Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residue (biochemistry), residues. Proteins perform a vast array of functions within organisms, including Enzyme catalysis, catalysing metabolic reactions, DNA replication, Cell signaling, responding to stimuli, providing Cytoskeleton, structure to cells and Fibrous protein, organisms, and Intracellular transport, transporting molecules from one location to another. Proteins differ from one another primarily in their sequence of amino acids, which is dictated by the Nucleic acid sequence, nucleotide sequence of their genes, and which usually results in protein folding into a specific Protein structure, 3D structure that determines its activity. A linear chain of amino acid residues is called a polypeptide. A protein contains at least one long polypeptide. Short polypeptides, containing less than 20–30 residues, are rarely considered to be proteins and are commonly called pep ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Laser Pulse
A laser is a device that emits light through a process of optical amplification based on the stimulated emission of electromagnetic radiation. The word ''laser'' originated as an acronym for light amplification by stimulated emission of radiation. The first laser was built in 1960 by Theodore Maiman at Hughes Research Laboratories, based on theoretical work by Charles H. Townes and Arthur Leonard Schawlow and the optical amplifier patented by Gordon Gould. A laser differs from other sources of light in that it emits light that is ''coherent''. Spatial coherence allows a laser to be focused to a tight spot, enabling uses such as optical communication, laser cutting, and lithography. It also allows a laser beam to stay narrow over great distances ( collimation), used in laser pointers, lidar, and free-space optical communication. Lasers can also have high temporal coherence, which permits them to emit light with a very narrow frequency spectrum. Temporal coherence can also ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biological Macromolecule
A macromolecule is a "molecule of high relative molecular mass, the structure of which essentially comprises the multiple repetition of units derived, actually or conceptually, from molecules of low relative molecular mass." Polymers are physical examples of macromolecules. Common macromolecules are biopolymers (nucleic acids, proteins, and carbohydrate A carbohydrate () is a biomolecule composed of carbon (C), hydrogen (H), and oxygen (O) atoms. The typical hydrogen-to-oxygen atomic ratio is 2:1, analogous to that of water, and is represented by the empirical formula (where ''m'' and ''n'' ...s). and polyolefins (polyethylene) and polyamides (nylon). Synthetic macromolecules Many macromolecules are synthetic polymers (plastics, synthetic fibers, and synthetic rubber. Polyethylene is produced on a particularly large scale such that ethylene is the primary product in the chemical industry. Macromolecules in nature * Proteins are polymers of amino acids joined by pe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mass Spectrometry
Mass spectrometry (MS) is an analytical technique that is used to measure the mass-to-charge ratio of ions. The results are presented as a ''mass spectrum'', a plot of intensity as a function of the mass-to-charge ratio. Mass spectrometry is used in many different fields and is applied to pure samples as well as complex mixtures. A mass spectrum is a type of plot of the ion signal as a function of the mass-to-charge ratio. These spectra are used to determine the elemental or isotopic signature of a sample, the masses of particles and of molecules, and to elucidate the chemical identity or structure of molecules and other chemical compounds. In a typical MS procedure, a sample, which may be solid, liquid, or gaseous, is ionization, ionized, for example by bombarding it with a Electron ionization, beam of electrons. This may cause some of the sample's molecules to break up into positively charged fragments or simply become positively charged without fragmenting. These ions (fragmen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ionisation
Ionization or ionisation is the process by which an atom or a molecule acquires a negative or positive charge by gaining or losing electrons, often in conjunction with other chemical changes. The resulting electrically charged atom or molecule is called an ion. Ionization can result from the loss of an electron after collisions with subatomic particles, collisions with other atoms, molecules, electrons, positrons, protons, antiprotons, and ions, or through the interaction with electromagnetic radiation. Heterolytic bond cleavage and heterolytic substitution reactions can result in the formation of ion pairs. Ionization can occur through radioactive decay by the internal conversion process, in which an excited nucleus transfers its energy to one of the inner-shell electrons causing it to be ejected. Uses Everyday examples of gas ionization occur within a fluorescent lamp or other electrical discharge lamps. It is also used in radiation detectors such as the Geiger-Müller ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Soft Laser Desorption
Soft laser desorption (SLD) is laser desorption of large molecules that results in ionization without fragmentation. "Soft" in the context of ion formation means forming ions without breaking chemical bonds. "Hard" ionization is the formation of ions with the breaking of bonds and the formation of fragment ions. Background The term "soft laser desorption" has not been widely used by the mass spectrometry community, which in most cases uses matrix-assisted laser desorption/ionization (MALDI) to indicate soft laser desorption ionization that is aided by a separate matrix compound. The term soft laser desorption was used most notably by the Nobel Foundation in public information released in conjunction with the 2002 Nobel Prize in Chemistry. Koichi Tanaka was awarded 1/4 of the prize for his use of a mixture of cobalt nanoparticles and glycerol in what he called the “ultra fine metal plus liquid matrix method” of laser desorption ionization. With this approach, he was able to demons ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Koichi Tanaka
is a Japanese electrical engineer who shared the Nobel Prize in Chemistry in 2002 for developing a novel method for mass spectrometric analyses of biological macromolecules with John Bennett Fenn and Kurt Wüthrich (the latter for work in NMR spectroscopy). Early life and education Tanaka was born and raised in Toyama, Japan, his biological mother died one month after he was born. Tanaka graduated from Tohoku University with a bachelor's degree in electrical engineering in 1983, afterward he joined Shimadzu Corporation, where he engaged in the development of mass spectrometers. Soft laser desorption For mass spectrometry analyses of a macromolecule, such as a protein, the analyte must be ionized and vaporized by laser irradiation. The problem is that the direct irradiation of an intense laser pulse on a macromolecule causes cleavage of the analyte into tiny fragments and the loss of its structure. In February 1985, Tanaka found that by using a mixture of ultra fine metal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Osamu Shimomura
was a Japanese organic chemist and marine biologist, and professor emeritus at Marine Biological Laboratory (MBL) in Woods Hole, Massachusetts and Boston University School of Medicine. He was awarded the Nobel Prize in Chemistry in 2008 for the discovery and development of green fluorescent protein (GFP) with two American scientists: Martin Chalfie of Columbia University and Roger Tsien of the University of California-San Diego. Biography Born in Fukuchiyama, Kyoto in 1928, Shimomura was brought up in Manchukuo (Manchuria, China) and Osaka, Japan while his father served as an officer in the Imperial Japanese Army. Later, his family moved to Isahaya, Nagasaki, 25 km from the epicenter of the August 1945 atomic bombing of the city. He recalled hearing, as a 16-year-old boy, the bomber plane ''Bockscar'' before the atom bomb exploded.Nobelprize.org Nobel laureate lecture.December 8, 2008. The explosion flash blinded Shimomura for about thirty seconds, and he was late ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Luciferin
Luciferin () is a generic term for the light-emitting chemical compound, compound found in organisms that generate bioluminescence. Luciferins typically undergo an enzyme-catalyzed reaction with Oxygen, molecular oxygen. The resulting transformation, which usually involves breaking off a molecular fragment, produces an excited state intermediate that emits light upon decaying to its ground state. The term may refer to molecules that are substrates for both luciferases and photoproteins. Types Luciferins are a class of small-molecule substrate (biochemistry), substrates that react with oxygen in the presence of a luciferase (an enzyme) to release energy in the form of light. It is not known just how many types of luciferins there are, but some of the better-studied compounds are listed below. Because of the chemical diversity of luciferins, there is no clear unifying mechanism of action, except that all require molecular oxygen, The variety of luciferins and luciferases, their ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
