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Mold ... molecular orbital

Mold: town, historic and present county of Flintshire (Sir Fflint), northeastern Wales, situated on a small stretch of farmland between the two industrial centres of Deeside and Wrexham. Mold grew up around a motte-and-bailey castle that the Normans built in the 12th century. The native Christian Britons of the area defeated ... [1 Related Articles]
mold: in manufacturing, a cavity or matrix in which a fluid or plastic substance is shaped into a desired finished product. A molten substance, such as metal, or a plastic substance is poured or forced into a mold and allowed to harden. Molds are made of a wide variety of materials, ... [17 Related Articles]
mold box: (from the article "founding") ...in two halves, and the two halves are joined together once the pattern has been removed from them. Pins and bushings permit precise joining of the two halves, which together are enclosed in a mold box. The metal is then poured into the mold through special gates and is distributed ...
Moldavia: principality on the lower Danube River that joined Walachia to form the nation of Romania in 1859. Its name was taken from the Moldovo River. It was founded in the first half of the 14th century by a group of Vlachs, led by Dragos, who emigrated southward from Maramures in ... [13 Related Articles]
Moldavian Plateau: (from the article "Romania") ...Transylvanian Basin is the largest in the country and has an average elevation of 1,150 feet (350 metres). In the east, between the outer fringe of the Subcarpathians and the Prut River, lies the Moldavian Plateau, with an average elevation of 1,600 to 2,000 feet (500 to 600 metres). The ...
moldboard: (from the article "agricultural technology") Equipment used to break and loosen soil for a depth of six to 36 inches (15 to 90 centimetres) may be called primary tillage equipment. It includes moldboard, disk, rotary, chisel, and subsoil plows.plow developmentplow...the heavier soils of northwestern Europe. ...
Molde: town, western Norway. It lies along Molde Fjord, an inlet of the Norwegian Sea. A port since the 15th century, Molde was partially destroyed by fire in 1916, damaged during World War II, then rebuilt completely. During April 1940 it was the temporary home of the Norwegian government. Local industry ...
molder: (from the article "baking") The molder receives pieces of dough from the intermediate proofer and shapes them into cylinders ready to be placed in the pans. There are several types of molders, but all have four functions in common: sheeting, curling, rolling, and sealing (see Figure 6). The dough as it comes from the ...
molding: (from the article "joint") ...ends. This enables one of the halves to glide over the other during the passage of the child through the mother's pelvis during birth, thus reducing the width of its skull, a process called molding. (The effects of molding usually disappear quickly.) After birth, all sutures become immobile joints. The ...
molding: in architecture and the decorative arts, a defining, transitional, or terminal element that contours or outlines the edges and surfaces on a projection or cavity, such as a cornice, architrave, capital, arch, base, or jamb. The surface of a molding is modeled with recesses and reliefs, which either maintain a ... [1 Related Articles]
Moldova: country lying in the northeastern corner of the Balkan region of Europe. Formerly known as Bessarabia, this region was an integral part of the Romanian principality of Moldavia until 1812, when it was ceded to Russia by its suzerain, the sultan of the Ottoman Empire. Bessarabia remained a province of ... [21 Related Articles]
Moldova Academy of Sciences: (from the article "Moldova") The Moldova Academy of Sciences, established in Chisinau in 1946, coordinates the activities of scientific institutions. In addition, dozens of research centres in the fields of viticulture, horticulture, beet growing, grain cultivation, and wine making have been set up, and Moldovan scientists have won international acclaim in these fields.
Moldova, flag of: vertically striped blue-yellow-red national flag with a central coat of arms featuring an eagle. The flag has a width-to-length ratio of 1 to 2.
Moldova, history of: (from the article "Moldova") Bessarabia-the name often given to the region of historical Moldavia between the Dniester and Prut rivers-has a long and stormy history. Part of Scythia in the 1st millennium BCE, Bessarabia later came marginally under the control of the Roman Empire as part of Dacia. Lying on one of the principal ...
Moldovan language: (from the article "Romanian language") ...the Megleno-Romanian, Istro-Romanian, and Aromanian are sometimes classed as languages distinct from Romanian proper, or Daco-Romanian, which has many slightly varying dialects of its own. Moldovan, the national language of Moldova, is a form of Daco-Romanian. It is written in the Latin alphabet.use in Moldova
Moldovan literature: (from the article "Moldova") Moldovan literature experienced the vicissitudes of Soviet literature generally during the late 1940s and early 1950s. Building socialism and creating the new Soviet citizen were the dominant themes, and socialist goals prevailed over aesthetic considerations. Characteristic of these trends were the early prose and poetry of Emilian Bucov and...
Moldoveanu, Mount: (from the article "Fagaras Mountains") ...gradient south to the Carpathian foothills. The mountains are heavily glaciated, with lakes, fretted peaks, and morainic deposits. The Olt breach defines the western end, the Bran Pass the eastern. Moldoveanu (8,346 feet [2,544 m]) and Negoiu (8,317 feet [2,535 m]) are the highest peaks. On the northern face many ...
mole: any of 42 species of insectivores, most of which are adapted for aggressive burrowing and for living most of their lives underground. Burrowing moles have a cylindrical body with a short tail and short, stocky limbs. A long, nearly hairless, and highly mobile piglike muzzle extends beyond the upper lip. ... [6 Related Articles]
mole: (from the article "tunnels and underground excavations") Since their first success in 1954, moles (mining machines) have been rapidly adopted worldwide. Close copies of the Oahe moles were used for similar large-diameter tunnels in clay shale at Gardiner Dam in Canada and at Mangla Dam in Pakistan during the mid-1960s, and subsequent moles have succeeded at many ...
mole: in dermatology, pigmented, flat or fleshy skin lesion, composed for the most part of an aggregation of melanocytes, the cells of the skin that synthesize the pigment melanin. In thicker moles, nerve elements and connective tissue are also present. Moles vary in colour from light to dark brown or black; ... [2 Related Articles]
mole: in chemistry, a standard scientific unit for measuring large quantities of very small entities such as atoms, molecules, or other specified particles. [4 Related Articles]
mole crab: crab of the Atlantic beaches from New England to Mexico. It is so named from its digging mole-fashion in sand. The shell is about 3.75 centimetres (1.5 inches) long, somewhat egg shaped and yellowish white with purplish markings. It lives on beaches in the intertidal zone. E. analoga, a broader ...
mole cricket: any of about 65 species of insects (order Orthoptera) that are sometimes placed in the true cricket family, Gryllidae. The common name is derived from the insect's molelike appearance and underground habits. The mole cricket has forelegs modified for shovelling, a cylindrical body, a pointed head, and a velvety coat ...
mole fraction: (from the article "liquid") It often is useful to express the composition of nonelectrolyte solutions in terms of mole fraction or mole percentage. In a binary mixture-i.e., a mixture of two components, 1 and 2-there are two mole fractions, x₁ and x₂, which satisfy the relation x₁ + x₂ = 1. The mole fraction ...
Mole National Park: (from the article "Principal national parks of the world") The Mole National Park near Damongo is about 1,900 square miles (4,900 square km) in extent and has an abundant game population including elephants, monkeys, and crocodiles. The newer Kakum National Park, which is located about 14 miles (22 km) north of Cape Coast and opened to the public in ...
Mole Saint-Nicolas: village, just northeast of Cap Saint-Nicolas, on the northwestern coast of Haiti. Situated on an inlet of the Windward Passage (a strait between Haiti and Cuba), it is the site where Christopher Columbus first landed (Dec. 6, 1492) on the island, which he named La Isla Espanola (taken into English ...
Mole Valley: district, administrative and historic county of Surrey, England. The River Mole, from which the district takes its name, flows northward across it to join the Thames at Hampton Court, west of London; the river cuts through a line of chalk hills (the North Downs) in a steep-sided valley that is ...
mole vole: (from the article "vole") ...whose pathways extend along and cross over springs and streams. Their burrow entrances may be at water level or submerged. Their diet consists of roots, rhizomes, and preformed buds of perennials. Mole voles (genus Ellobius) have tiny eyes and ears and the velvety fur common to burrowing rodents. Mole voles ...
Mole, Abraham: (from the article "music") The French theorist Abraham Moles's Information Theory and Esthetic Perception (1966) brings the new science of information theory to bear on musical perception, emphasizing that the concept of form is the essential thing; the "sonic message," whose dimensions vary from one composition to another, is a whole. Information theory thus ...
Mole, Louis-Mathieu, Comte: French monarchist statesman who held office under Napoleon I, Louis XVIII, and Louis-Philippe.
Mole, River: (from the article "Mole Valley") district, administrative and historic county of Surrey, England. The River Mole, from which the district takes its name, flows northward across it to join the Thames at Hampton Court, west of London; the river cuts through a line of chalk hills (the North Downs) in a steep-sided valley that is ...
molecular activation: (from the article "radiation") A molecule is considered activated when it absorbs energy by interaction with radiation. In this energy-rich state it may undergo a variety of unusual chemical reactions that are normally not available to it in thermal equilibrium. Of special importance is electronic activation-i.e., production of an electronically excited state of the ...
molecular beam: any stream or ray of molecules moving in the same general direction, usually in a vacuum-i.e., inside an evacuated chamber. In this context the word molecule includes atoms as a special case. Most commonly, the molecules comprising the beam are at a low density; that is, they are far enough ... [3 Related Articles]
molecular binding: (from the article "crystal") The Dutch physicist Johannes D. van der Waals first proposed the force that binds molecular solids. Any two atoms or molecules have a force of attraction (F) that varies according to the inverse seventh power of the distance R between the centres of the atoms or molecules: F = −C/R⁷, ...
molecular biology: field of science concerned with studying the chemical structures and processes of biological phenomena that involve the basic units of life, molecules. Of growing importance since the 1940s, molecular biology developed out of the related fields of biochemistry, genetics, and biophysics. The discipline is particularly concerned with the study of ... [31 Related Articles]
molecular branching: (from the article "elastomer") Some rubbery solids are made by simultaneous polymerization and interlinking. If during polymerization each unit can add more than one other unit, then as the molecule increases in size it will branch out with many arms that will divide and interlink to create a densely cross-linked solid. The length of ...
molecular clock: (from the article "conservation") ...the split from their common ancestor. Studies show that these accumulated differences result from changes whose rates are, in a certain fashion, fairly constant-hence, the concept of the molecular clock (see evolution: The molecular clock of evolution)-which allows scientists to estimate the time of the split from knowledge of the ...
molecular cloud: (from the article "nebula") ...(H⁺) are called H II regions; those in which hydrogen is mainly neutral are designated H I regions; and those in which the gas is in molecular form (H₂) are referred to as molecular clouds. The distinction is important because neutral hydrogen atoms are extremely efficient at absorbing ionizing radiation, ...
molecular crystal: (from the article "chemical bonding") The structures of molecular solids, which are solids composed of individual molecules, have also been touched on in the section on intermolecular forces. These molecules are held to one another by hydrogen bonds (if they can form them), dispersion forces, and other dipolar forces-in that order of decreasing importance-and the ...
molecular dynamics: (from the article "chemical kinetics") The second theoretical approach to chemical kinetics is referred to as molecular dynamics, or reaction dynamics. It is a more detailed treatment of reactions and is designed to investigate the atomic motions that occur during a chemical reaction and the quantum states of the reactant and product molecules. Such studies ...
molecular electronics: (from the article "nanotechnology") The use of molecules for electronic devices was suggested by Mark Ratner of Northwestern University and Avi Aviram of IBM as early as the 1970s, but proper nanotechnology tools did not become available until the turn of the 21st century. Wiring up molecules some half a nanometre wide and a ...
molecular energy level: (from the article "excitation") in physics, the addition of a discrete amount of energy (called excitation energy) to a system-such as an atomic nucleus, an atom, or a molecule-that results in its alteration, ordinarily from the condition of lowest energy (ground state) to one of higher energy (excited state).molecular spectra
molecular evolution: (from the article "evolution") Molecular evolution
molecular field theory: (from the article "magnetism") A simple empirical representation of the effect of such exchange forces invokes the idea of an effective internal, or molecular, field H_int, which is proportional in size to the magnetization M; that is, H_int = lambdaM in which ...
molecular formula: (from the article "mass spectrometry") ...and C₄H₄O₂⁺ are, for example, 84.0939 and 84.0211, respectively, and these ions can easily be distinguished solely on the basis of their masses. Once the molecular formula is known it is possible to deduce the total of rings and double bonds making up the molecular structure and to begin to ...
molecular genetics: (from the article "heredity") The data accumulated by scientists of the early 20th century provided compelling evidence that chromosomes are the carriers of genes. But the nature of the genes themselves remained a mystery, as did the mechanism by which they exert their influence. Molecular genetics-the study of the structure and function of genes ...
molecular ion: (from the article "mass spectrometry") ...study of organic compounds, which can be introduced as vapours and ionized in the intense fields. The ions are formed with very little excitation energy, so that there is little fragmentation of the molecular ions, making molecular formulas easier to determine.
molecular laser isotope separation: (from the article "isotope") ...for isotope separation in which light is used to excite one and only one isotope of an element. In atomic vapour laser isotope separation (AVLIS), the starting material is the element itself; in molecular laser isotope separation (MLIS), the starting material is a chemical compound containing the element. Ordinary light ...
molecular lattice: (from the article "halogen element") ...only element that is liquid at 20 °C (68 °F) and atmospheric pressure. Iodine (I₂) forms dark violet crystals under these conditions. In the solid state the halogen elements form molecular lattices, and the sublimation energies rise with increasing size of the molecules.
molecular mechanics: (from the article "hydrocarbon") ...and electron diffraction analyses and infrared, nuclear magnetic resonance, and microwave spectroscopies. These experimental techniques have been joined by advances in computational methods such as molecular mechanics, whereby the total strain energies of various conformations are calculated and compared (see also chemical bonding: Computational approaches to molecular structure). The...
molecular orbital: (from the article "chemical bonding") Just as an atomic orbital is a wavefunction that describes the distribution of an electron around the nucleus of an atom, so a molecular orbital (an MO) is a wavefunction that describes the distribution of an electron over all the nuclei of a molecule. If the amplitude of the MO ...