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Molecular Machine
A molecular machine, nanite, or nanomachine is a molecular component that produces quasi-mechanical movements (output) in response to specific stimuli (input). In cellular biology, macromolecular machines frequently perform tasks essential for life, such as DNA replication and ATP synthesis. The expression is often more generally applied to molecules that simply mimic functions that occur at the macroscopic level. The term is also common in nanotechnology where a number of highly complex molecular machines have been proposed that are aimed at the goal of constructing a molecular assembler. For the last several decades, chemists and physicists alike have attempted, with varying degrees of success, to miniaturize machines found in the macroscopic world. Molecular machines are at the forefront of cellular biology research. The 2016 Nobel Prize in Chemistry was awarded to Jean-Pierre Sauvage, Sir J. Fraser Stoddart, and Bernard L. Feringa for the design and synthesis of molecular ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cellular Biology
Cell biology (also cellular biology or cytology) is a branch of biology that studies the structure, function, and behavior of cells. All living organisms are made of cells. A cell is the basic unit of life that is responsible for the living and functioning of organisms. Cell biology is the study of structural and functional units of cells. Cell biology encompasses both prokaryotic and eukaryotic cells and has many subtopics which may include the study of cell metabolism, cell communication, cell cycle, biochemistry, and cell composition. The study of cells is performed using several microscopy techniques, cell culture, and cell fractionation. These have allowed for and are currently being used for discoveries and research pertaining to how cells function, ultimately giving insight into understanding larger organisms. Knowing the components of cells and how cells work is fundamental to all biological sciences while also being essential for research in biomedical fields such as ca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mechanically Interlocked Molecular Architectures
In chemistry, mechanically-interlocked molecular architectures (MIMAs) are molecules that are connected as a consequence of their topology. This connection of molecules is analogous to keys on a keychain loop. The keys are not directly connected to the keychain loop but they cannot be separated without breaking the loop. On the molecular level, the interlocked molecules cannot be separated without the breaking of the covalent bonds that comprise the conjoined molecules; this is referred to as a mechanical bond. Examples of mechanically interlocked molecular architectures include catenanes, rotaxanes, molecular knots, and molecular Borromean rings. Work in this area was recognized with the 2016 Nobel Prize in Chemistry to Bernard L. Feringa, Jean-Pierre Sauvage, and J. Fraser Stoddart. The synthesis of such entangled architectures has been made efficient by combining supramolecular chemistry with traditional covalent synthesis, however mechanically interlocked molecular architectu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nanocar Race
Nanocar Race is an international scientific competition with the aim of testing the performance of molecular machines and the scientific instruments used to control them. The race of the molecules takes place on a 100 nanometer track and was held for the first time in Toulouse on 28 and 29 April 2017. History The idea for the race was formulated in January 2013 in the ACS Nano magazine by the Toulouse organizers of CEMES-CNRS, this way a call for applications was launched to give the participating teams time to prepare appropriate nanocars. The race is officially announced by the National Centre for Scientific Research in November 2015 in Toulouse during Futurapolis1. On this occasion, five teams presented their prototype projects on November 27, 2015. The first race in the world of this type, between four vehicles, started on the 28 April 2017 at the CEMES-CNRS in Toulouse and lasted 36 hours. The Toulouse organizers also agreed on the competition of two more vehicles, which wil ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fullerenes
A fullerene is an allotrope of carbon whose molecule consists of carbon atoms connected by single and double bonds so as to form a closed or partially closed mesh, with fused rings of five to seven atoms. The molecule may be a hollow sphere, ellipsoid, tube, or many other shapes and sizes. Graphene (isolated atomic layers of graphite), which is a flat mesh of regular hexagonal rings, can be seen as an extreme member of the family. Fullerenes with a closed mesh topology are informally denoted by their empirical formula C''n'', often written C''n'', where ''n'' is the number of carbon atoms. However, for some values of ''n'' there may be more than one isomer. The family is named after buckminsterfullerene (C60), the most famous member, which in turn is named after Buckminster Fuller. The closed fullerenes, especially C60, are also informally called buckyballs for their resemblance to the standard ball of association football ("soccer"). Nested closed fullerenes have been named ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
James M
James is a common English language surname and given name: *James (name), the typically masculine first name James * James (surname), various people with the last name James James or James City may also refer to: People * King James (other), various kings named James * Saint James (other) * James (musician) * James, brother of Jesus Places Canada * James Bay, a large body of water * James, Ontario United Kingdom * James College, a college of the University of York United States * James, Georgia, an unincorporated community * James, Iowa, an unincorporated community * James City, North Carolina * James City County, Virginia ** James City (Virginia Company) ** James City Shire * James City, Pennsylvania * St. James City, Florida Arts, entertainment, and media * ''James'' (2005 film), a Bollywood film * ''James'' (2008 film), an Irish short film * ''James'' (2022 film), an Indian Kannada-language film * James the Red Engine, a character in ''Thomas the Tank En ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nanocar
The nanocar is a molecule designed in 2005 at Rice University by a group headed by Professor James Tour. Despite the name, the original nanocar does not contain a molecular motor, hence, it is not really a car. Rather, it was designed to answer the question of how fullerenes move about on metal surfaces; specifically, whether they roll or slide (they roll). The molecule consists of an H-shaped 'chassis' with fullerene groups attached at the four corners to act as wheels. When dispersed on a gold surface, the molecules attach themselves to the surface via their fullerene groups and are detected via scanning tunneling microscopy. One can deduce their orientation as the frame length is a little shorter than its width. Upon heating the surface to 200 °C the molecules move forward and back as they roll on their fullerene "wheels". The nanocar is able to roll about because the fullerene wheel is fitted to the alkyne "axle" through a carbon-carbon single bond. The hydrogen on the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Molecular Switch
A molecular switch is a molecule that can be reversibly shifted between two or more stable states. The molecules may be shifted between the states in response to environmental stimuli, such as changes in pH, light, temperature, an electric current, microenvironment, or in the presence of ions and other ligands. In some cases, a combination of stimuli is required. The oldest forms of synthetic molecular switches are pH indicators, which display distinct colors as a function of pH. Currently synthetic molecular switches are of interest in the field of nanotechnology for application in molecular computers or responsive drug delivery systems. Molecular switches are also important in biology because many biological functions are based on it, for instance allosteric regulation and vision. They are also one of the simplest examples of molecular machines. Biological molecular switches In cellular biology, proteins act as intracellular signaling molecules by activating another protein i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Photoswitch
A photoswitch is a type of molecule that can change its structural geometry and chemical properties upon irradiation with electromagnetic radiation. Although often used interchangeably with the term molecular machine, a switch does not perform work upon a change in its shape whereas a machine does. However, photochromic compounds are the necessary building blocks for light driven molecular motors and machines. Upon irradiation with light, photoisomerization about double bonds in the molecule can lead to changes in the cis- or trans- configuration. These photochromic molecules are being considered for a range of applications. Chemical structures and properties A photochromic compound can change its configuration or structure upon irradiation with light. Several examples of photochromic compounds include: azobenzene, spiropyran, merocyanine, diarylethene, spirooxazine, fulgide, hydrazone, nobormadiene, thioindigo, acrylamide-azobenzene-quaternary ammonia, donor-acceptor Stenhouse ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Molecular Switch
A molecular switch is a molecule that can be reversibly shifted between two or more stable states. The molecules may be shifted between the states in response to environmental stimuli, such as changes in pH, light, temperature, an electric current, microenvironment, or in the presence of ions and other ligands. In some cases, a combination of stimuli is required. The oldest forms of synthetic molecular switches are pH indicators, which display distinct colors as a function of pH. Currently synthetic molecular switches are of interest in the field of nanotechnology for application in molecular computers or responsive drug delivery systems. Molecular switches are also important in biology because many biological functions are based on it, for instance allosteric regulation and vision. They are also one of the simplest examples of molecular machines. Biological molecular switches In cellular biology, proteins act as intracellular signaling molecules by activating another protein i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Daisy Chain Rotaxane
Daisy, Daisies or DAISY may refer to: Plants * ''Bellis perennis'', the common daisy, lawn daisy or English daisy, a European species Other plants known as daisy * Asteraceae, daisy family ** ''Euryops chrysanthemoides'', African bush daisy ** ''Osteospermum'', African daisy ** ''Tetraneuris acaulis'', angelita daisy ** ''Melampodium leucanthum'', blackfoot daisy ** ''Glebionis coronaria'', crown daisy ** ''Brachyglottis greyi'', daisy bush ** ''Olearia'', daisy bush ** '' Argyranthemum'', dill daisy, marguerite daisy ** ''Rhodanthemum hosmariense'', Moroccan daisy ** '' Leucanthemum vulgare'', oxeye daisy, dog daisy ** ''Leucanthemum × superbum'', Shasta daisy ** ''Brachyscome'', several species ** ''Gerbera jamesonii'', Barberton daisy, Transvaal daisy ** ''Ismelia carinata'', tricolor daisy * ''Scabiosa prolifera'', Carmel daisy * ''Globularia'', globe daisies * ''Cleretum bellidiforme'', Livingstone daisy Arts, entertainment and media Film and television * Daisy (advertisemen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Molecular Gyroscope
Molecular gyroscopes are chemical compounds or supramolecular complexes containing a rotor that moves freely relative to a stator, and therefore act as gyroscopes. Though any single bond or triple bond permits a chemical group to freely rotate, the compounds described as gyroscopes may protect the rotor from interactions, such as in a crystal structure with low packing density or by physically surrounding the rotor avoiding steric contact. A qualitative distinction can be made based on whether the activation energy needed to overcome rotational barriers is higher than the available thermal energy. If the activation energy required is higher than the available thermal energy, the rotor undergoes "site exchange", jumping in discrete steps between local energy minima on the potential energy surface. If there is thermal energy sufficiently higher than that needed to overcome the barrier to rotation, the molecular rotor can behave more like a macroscopic freely rotating inertial mass. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Molecular Propeller
Molecular propeller is a molecule that can propel fluids when rotated, due to its special shape that is designed in analogy to macroscopic propellers: it has several molecular-scale blades attached at a certain pitch angle around the circumference of a shaft, aligned along the rotational axis. The molecular propellers designed in the group of Prof. Petr Král from the University of Illinois at Chicago have their blades formed by planar aromatic molecules and the shaft is a carbon nanotube. Molecular dynamics simulations show that these propellers can serve as efficient pumps in the bulk and at the surfaces of liquids. Their pumping efficiency depends on the chemistry of the interface between the blades and the liquid. For example, if the blades are hydrophobic, water molecules do not bind to them, and the propellers can pump them well. If the blades are hydrophilic, water molecules form hydrogen bonds with the atoms in the polar blades. This can largely block the flow of other w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
