ENCYCLOPEDIA -Volume 3

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  • 1. M Maltose Maltose (/mltos/ or also known asmaltobiose or malt sugar, is a disaccharide formed from two units of glucose joined with an (14) bond, formed from a condensation reaction. The isomerisomaltose has two glucose molecules linked through an (16) bond. Maltose is the second member of an important biochemical series of glucose chains. Maltose is the disaccharide produced when amylase breaks downstarch. It is found in germinating seeds such as barley as they break down their starch stores to use for food. It is also produced when glucose is caramelized. Maltose was discovered by Ireland's Cornelius OSullivanin 1872[5] and its name comes from malt, from Old English mealt, of Germanic origin, and the suffix ose, a suffix forming names of sugars and other carbohydrates. Maltose -Maltose

2. Maltose is a biomolecule that belongs to the group of 90 carbohydrates within the division into three groups, which are divided into essential elements: carbohydrates, lipids and proteins. Carbohydrates are composed by O, H, C, and are defined as polyhydroxyaldehydes or polyhydroxyketones. It is generally divided into monosaccharides, oligosaccharides and polysaccharides depending on the number of residues. Maltose is a disaccharide formed by the union of two glucose units (monosaccharide). The two are classified as hexoses because each one is composed of six carbons. The two glucoses which compose maltose are cyclized in piran form and are joined by an O-glycosidic bond through one of the firstglucose carbon and fourth carbon of the second glucose, indicated as (1 4). The link is characterized as due to the -OH position of the anomeric carbon in the opposite plane of CH2OH radical (the carbon is the number 6).Due to O-glycosidic link, maltose is a disaccharide that can reduce Fehling's reagent. Furthermore, maltose can be obtained by hydrolysis of glycogen or starch, polymers of linked maltoses in position (1 4) and branching in position (1 6). These are very abundant and form a large number of branches. Amylase enzymes produce maltose and limit dextrin. These can be further degraded by maltase enzyme to hydrolyze maltoses as glucoses and they are ready to be degrade and obtain energy in form of ATP. Maltose has the ability to reduce the Fehlings solution, due to its free aldehyde. The aldehyde group is oxidized giving a positive result, which means that the maltose is a reducing sugar. Maltose in aqueous solution exhibit mutarotation, due to its anomeric carbon which can form and isomers. In aqueous solution, it is shown a balanced way between and forms. It has a sweet taste. Lu and Sharkey in 2006 said that maltose was the main carbon form exported from chloroplasts at night. MANTLE 3. The mantle is a part of a terrestrial planet or other rocky body large enough to have differentiation by density. The interior of 91 the Earth, similar to the other terrestrial planets, is chemically divided into layers. The mantle is a layer between the crust and the outer core. Earth's mantle is a silicate rocky shell about 2,900 km (1,800 mi) thick that constitutes about 84% of Earth's volume. It is predominantly solid but in geological time it behaves like very viscous liquid. The mantle encloses the hot core rich in iron and nickel, which occupies about 15% of Earth's volume. Past episodes of melting and volcanism at the shallower levels of the mantle have produced a thin crust of crystallized melt products near the surface, upon which we live.[4] Information about structure and composition of the mantle either result from geophysical investigation or from direct geoscientific analyses on Earth mantle derived xenoliths and on mantle exposed by mid- oceanic ridge spreading. The Structure of the Earth 4. Two main zones are distinguished in the upper mantle: the inner asthenosphere composed of plastic flowing rock about 200 km thick,and the lowermost part of the lithosphere composed of rigid rock about 50 to 120 km thick. A thin crust, the upper 93 part of the lithosphere, surrounds the mantle and is about 5 to 75 km thick. In some places under the ocean the mantle is actually exposed on the surface of the Earth. There are also a few places on land where mantle rock has been pushed to the surface by tectonic activity, most notably the Tablelands region of Gros Morne National Park in the Canadian province of Newfoundland. The mantle is divided into sections which are based upon results from seismology. These layers (and their thicknesses/depths) are the following: the upper mantle (starting at the Moho, or base of the crust around 7 to 35 km downward to 410 km),the transition zone (410660 km), the lower mantle (6602891 km), and anomalous coremantle boundary with a variable thickness (on average ~200 km thick). The top of the mantle is defined by a sudden increase in seismic velocity, which was first noted by Andrija Mohorovii in 1909; this boundary is now referred to as the "Mohorovii discontinuity" or "Moho". The uppermost mantle plus overlying crust are relatively rigid and form the lithosphere, an irregular layer with a maximum thickness of perhaps 200 km, below the lithosphere the upper mantle becomes notably more plastic. In some regions below the lithosphere, the seismic velocity is reduced; this so-called low-velocity zone (LVZ) extends down to a depth of several hundred km. Inge Lehmann discovered a seismic discontinuity at about 220 km depth; although this discontinuity has been found in other studies, it is not known whether the discontinuity is ubiquitous. The transition zone is an area of great complexity; it physically separates the upper and lower mantle. Very little is known about the lower mantle apart from that it appears to be relatively seismically homogeneous. The D" layers at the core mantle boundary separates the mantle from the core. MOMENTUM 5. In classical mechanics, line ar momentum or translational 94 momentum (pl. m omenta; SI unit kg m/s, or equivalently, N s) is the product of the mass and veloci ty of an object. For example, a heavy truck moving fast has a large momentumit takes a large and prolonged force to get the truck up to this speed, and it takes a large and prolonged force to bring it to a stop afterwards. If the truck were lighter or moving more slowly, then it would have less momentum. Like velocity, linear momentum is a vector quantity, possessing a direction as well as a magnitude: Linear momentum is also a conserved quantity, meaning that if a closed system is not affected by external forces, its total linear momentum cannot change. In classical mechanics, conservation of linear momentum is implied by Newton's laws; but it also holds in special relativity (with a modified formula) and, with appropriate definitions, a (generalized) linear momentum conservation law holds in electrodynamics, mechanics, quantum, and general relativity. Momentum has a direction as well as magnitude. Quantities that have both a magnitude and a direction are known as vector quantities. Because momentum has a direction, it can be used to predict the resulting direction of objects after they collide, as well as their speeds. Below, the basic properties of momentum are described in one dimension. The vector equations are almost identical to the scalar equations (see multiple dimensions). Billiard balls possesses momentum. 6. 95 MUDSLIDE A mudslide is the most rapid (up to 80 km/h, or 50 mph) and fluid type of downhill mass wasting. It is a rapid movement of a large mass of mud formed from loose dirt and water. Similar phenomena include mudflow, mud stream, debris flow (e.g. in high mountains), jkulhlaup, and lahar (from volcanoes). These terms cover a broad variety in water content (from loamy mud, to almost liquid, and even steam); material (wet soil, sandy sediments and/or silt, dirt, rock, debris, volcanic ash, small plants, and even trees); length; total mass; and velocity. Heavy rainfall, snowmelt, or high levels of water flowing through cracked bedrock may trigger a movement of soil or sediments. Floods, debris- and mud flows may also occur when strong rains on hill or mountain slopes cause extensive erosion and/or what is known as "channel scour". The 2006 Sidoarjo mud flow may have been caused by rogue drilling. Some broad mudflows are rather viscous and therefore slow; others begin very quickly and continue like an avalanche. If Mailbox caught in a mudslide 7. large enough they can devastate villages and country sides. They are composed of at least 50% silt and clay-sized materials and up to 30% water. Mudflows are common even in 96 the hills around Los Angeles where they have destroyed many homes built on hillsides without sufficient support. The point where a muddy material begins to flow depends on its grain and the water content. Fine grainy material or soil has a smaller friction angle than a coarse sediment or a debris flow, but falling rock pieces can trigger a material flow, too. On December 14, 1999 in Vargas, Venezuela, a mudslide known as The Vargas tragedy, which significantly altered more than 60 kilometers (37 mi) of its coastline, was triggered due to heavy rainfall and caused estimated damages of USD $1.79 to $3.5 billion, a death toll considered to be between 10,000 and 30,000, 85,000 people evacuated and led to the complete collapse of the state's infrastructure. When a mudslide occurs it is given four named areas, the 'main scarp', in bigger mudslides the 'upper and lower shelves' and the 'toe'. The main scarp will be the original area of incidence; the toe is the last affected area(s). The upper and lower shelves are located wherever a large dip (due to mountain or natural drop) in the mudslides path. Due to this a mudslide can have many shelves. Myelin Myelin is a dielectric(electrically insulating) material that forms a layer, the myelin sheath, usually around only the axon of a neuron. It is essential for the proper functioning