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	Zone melting - Wikipedia, the free encyclopedia (Site not responding. Last check: 2007-10-20)
		Zone melting is a method of separation by melting in which a molten zone traverses a long ingot of impure metal or chemical.
		In zone leveling, the objective is to distribute solute evenly throughout the purified material, which may be sought in the form of a single crystal.
		Zone melting can be done as a batch process, or it can be done continuously, with fresh impure material being continually added at one end and purer material being removed from the other, with impure zone melt being removed at whatever rate is dictated by the impurity of the feed stock.
	en.wikipedia.org /wiki/Zone_melting (516 words)

	Zone melting -- Facts, Info, and Encyclopedia article (Site not responding. Last check: 2007-10-20)
		Zone melting is a method of separation by melting in which a series of molten zones traverses a long (A block of metal that is cast in a particular shape for convenient handling) ingot of impure metal or chemical.
		Zone refining was developed by the (Click link for more info and facts about Bell Telephone Laboratories) Bell Telephone Laboratories as a method to prepare high purity materials for manufacturing (A semiconductor device capable of amplification) transistors.
		In zone leveling, the objective is to distribute solute evenly throughout the purified material, which may be sought in the form of a single (A crystalline element used as a component in various electronic devices) crystal.
	www.absoluteastronomy.com /encyclopedia/z/zo/zone_melting.htm (415 words)

	Zone Melting (Site not responding. Last check: 2007-10-20)
		The portion of the cylinder containing the seed crystal is heated to the melting point, and the rest of the cylinder is slowly pulled through the hot zone.
		Zone melting setups are modifications of either the Bridgman or Stockbarger methods of crystal growth.
		An advantage of the zone melting technique is that impurities tend to be concentrated in the melted portion of the sample.
	www.chemistry.ohio-state.edu /~woodward/ch754/syn_zone.htm (151 words)

	Crystallization from the Melt (Site not responding. Last check: 2007-10-20)
		Zone melting techniques are very important in industrial crystallizations.
		The heat for the zone melting is generated by an ordinary lamp (for example from a slide projector).
		The light of the lamp is focused onto the capillary by the use of a concave mirror.
	www.cryst.chem.uu.nl /lutz/growing/melt.html (281 words)

	Floating zone melting apparatus - Patent 5762707
		The floating zone melting apparatus as claimed in claim 2, further comprising a plurality of fixed lamp holders connected to said infrared-ray lamps, wherein each of said holders are connected to said respective lamp via a socket which is movably attached to said holder such that a support position of said socket is variable.
		The floating zone melting apparatus as claimed in claim 6, further comprising a plurality of fixed lamp holders connected to said halogen lamps, wherein each of said holders are connected to said respective lamp via a socket which is movably attached to said holder such that a support position of said socket is variable.
		The floating zone melting apparatus as claimed in claim 1, further comprising a plurality of fixed lamp holders connected to said infrared-ray lamps, wherein each of said holders are connected to said respective lamp via a socket which is movably attached to said holder such that a support position of said socket is variable.
	www.freepatentsonline.com /5762707.html (4153 words)

	Zone melting (Site not responding. Last check: 2007-10-20)
		In zone refining, solutes are segregated at one end of the ingot in order to purify the remainder, or to concentrate theimpurities for analytical or other purposes.
		In zone leveling, the objective is to distribute solute evenlythroughout the purified material, which may be sought in the form of a single crystal.
		A variety of heaters can be used for zone melting, with their most important characteristic being the ability to form shortmolten zones that move slowly and uniformly through the ingot.
	www.therfcc.org /zone-melting-126346.html (393 words)

	Crucibleless Zone Melting of Metal and Alloy in Reflector/Ray Furnace RRF-1. (Site not responding. Last check: 2007-10-20)
		Purpose of the experiment on crucibleless zone melting (CZM) and crystallization was to investigate specific features of the process (CZM) taking into account specific conditions of processing by concentrated light energy and their effect on structure of the material received.
		In this case zinc is chosen as methodically convenient material with low melting temperature, well investigated at ground conditions, from study of convective mass-transferring point of view it is also interesting by presence of oxide film on the crystal and melt surface, which according to preliminary data prevents arising of thermocapillary convection.
		Melted zone was crystallized in the direction from the rest non-melted part as from seeding keeping its orientation.
	www.tsniimash.ru /Microgravity/1_3_eng.html (769 words)

	Applications (Site not responding. Last check: 2007-10-20)
		Wynne (1961) reported that the melting point of a zone-refined sample was 288.90 C and compared this with literature values of 286~288 C. Beynon and Saunders (1960) reported that anthraquinone can be purified satisfactorily by zone melting.
		After each zone pass all residual vapor was frozen into one of the traps by means of liquid nitrogen and the condensed vapor was isolated from the rest of the system.
		Handley and Herington (1956) found that a sample with a melting point of 250~250.5 C could be produced by zone melting a commercial sample with melting point 248-249.5 C. Wolf (1957) reports that an unidentified impurity was removed from this hydrocarbon by zone melting.
	www.designscientific.com /applications.htm (3635 words)

	Patent 6,248,386
		The sweetener is introduced into an inlet zone of the extruder, is extruded in a melting zone at an increased temperature, in a vacuum zone at a reduced pressure and increased temperature, and finally in a cooling zone at a reduced temperature, forming a vitreous molten mass.
		The melting zone is understood to means the area of the extruder in which the melting and decrystallisation of the inserted sweetening agent mixture takes place at elevated temperature.
		The cooling zone is understood to mean the area of the extruder in which the extrusion mass heated during the melting process is gradually cooled.
	www.pharmcast.com /Patents/Yr2001/June2001/061901/6248386_Caramels061901.htm (1474 words)

	Peridotites from the Izu-Bonin-Mariana Forearc (ODP Leg 125): Evidence for Mantle Melting and Melt-Mantle Interaction ...
		This is in part because physical parameters such as the advection of mantle and melt in the mantle wedge are poorly constrained, and in part because there is a dearth of `wet' peridotite melting experiments from which to study the composition of subduction zone melts and residues.
		Melt percolation and melt-mantle interaction are potentially important processes in modifying the composition of the mantle and its resultant melts (Spiegelman and McKenzie, 1987; McKenzie and O'Nions, 1991; Pearce and Parkinson, 1993).
		For the fractional melting trends two separate sets of partitioning data are used from Pearce and Parkinson, (1993), for 1300°C and 1200°C to illustrate the effects of varying the input parameters on the model calculations.
	library.iem.ac.ru /j-petr/9-3998/html/egb061_gml.html (13357 words)

	Mantle Ascent (Site not responding. Last check: 2007-10-20)
		The melt forms along a dendritic network of joints and fractures in the zone of melting, and feeds into a smaller number of layer tributaries eventually forming a larger channel at higher levels.
		With melting concentrated along grain boundaries, melt migration is caused by a thermal or pressure gradient or by capillary effects.
		Heat used in melting is regenerated by release of latent heat of crystallization.
	www.geo.ua.edu /volcanology/lecture_notes_files/mantle_ascent.html (379 words)

	SINGLE-SCREW EXTRUDER EXPERIMENT - Chemical Engineering Department Louisiana State University
		Extrusion involves transport and melting of the feed and pressure build-up and transport of the melt.
		The extruder is designed to: (a) ensure steady transport from the feeder to the melting zone; (b) allow for reduction in volume occuring as the pellets melt; (c) build up pressure; and finally, (d) transport the melt through the die attached to the extruder tip.
		Assuming that the extruder near the die may be approximated as a cylinder of uniform radius R, and the polymer melt maintains a constant fluid density, a differential momentum balance yields Eq.
	www.che.lsu.edu /faculty/dooley/EXTRUEXP.htm (937 words)

	ZONE MELTING
		Highly localized melting, usually by induction heating, of a small volume of an otherwise solid piece.
		By moving the induction coil along the rod, the melted zone can be transferred from one end to the other.
		In a binary mixture where there is a large difference in composition on the liquidus and solidus lines, high purity can be attained by concentrating one of theconstituents in the liquid as it moves along a rod.
	www.websters-online-dictionary.org /zo/zone+melting.html (783 words)

	Liquid encapsulated zone melting crystal growth method and apparatus - Patent 5007980
		A lower thermal gradient subzone 10 is located between the bottom of the central zone heating element and the lower furnace zone 5, and an upper thermal gradient subzone 12 is located between the top of the central zone heating element and the upper furnace zone 7.
		The principal requirements for the encapsulant are that it melt at a lower temperature than the crystal material; that it be at least substantially unreactive toward the crystal material and the crucible material, and that it not exhibit an excessive vapor pressure at the melting temperature of the crystal material.
		By maintaining a molten region within the spike zone which is considerably shorter in length than the lengths of the surrounding upper and lower furnace zones, the resulting growth interface shape is slightly convex with respect to the solid phase of the material, and an optimal single crystal can be grown.
	www.freepatentsonline.com /5007980.html (7773 words)

	Ocean 540: Mantle Flow and Crustal Generation
		Melt that reaches the crust has its origin in the mantle, with melting occurring as ascending mantle material adiabatically decompresses.
		Once within the field of melting, the effect of the negative heat of melting is to cause the temperature decrease with decreasing pressure to be steeper than the adiabat.
		Melted material migrates upward from the mantle to form the oceanic crust.
	www2.ocean.washington.edu /oc540/lec02-5 (1199 words)

	CONTROLS ON GNEISS DOME FORMATION: CHICKENS, EGGS AND RED HERRINGS (Site not responding. Last check: 2007-10-20)
		Increased buoyancy during melting could initiate diapirism, but this may be a red herring if tectonic controls do not allow the potential of reduced buoyancy to be realized (i.e.
		In the anatectic zone, decompression melting is limited because melt mode isopleths are nearly isothermal, except close to the solidus.
		Which of melting or decompression is chicken or egg is a matter of prejudice and may even be moot if dome formation is controlled by other factors.
	gsa.confex.com /gsa/2002AM/finalprogram/abstract_40385.htm (484 words)

	Liquid encapsulated zone melting crystal growth method and apparatus - US Patent 5057287 (Site not responding. Last check: 2007-10-20)
		In the preferred embodiment, all three zones are initially set at a temperature of 1200° C. This temperature will permit the dry boric oxide to melt and coat the interior of the growth crucible without melting the seed crystal or any of the precompounded crystal material.
		The temperature of the spike zone was permitted to drop to 1200° C. and the growth container was raised again, this time to a slightly higher position with the seed crystal extending part way into the molten subzone.
		The temperature of the molten subzone within the spike zone was again permitted to drop to a temperature in the range from 1100° to 1200° C., and the crystal growth container was raised all the way to the top of the furnace and the support rod was clamped in position.
	www.patentstorm.us /patents/5057287.html (6928 words)

	zone. The American Heritage® Dictionary of the English Language: Fourth Edition. 2000.
		Any of the five regions of the surface of the earth that are loosely divided according to prevailing climate and latitude, including the Torrid Zone, the North and South Temperate zones, and the North and South Frigid zones.
		A section of an area or territory established for a specific purpose, as a section of a city restricted to a particular type of building, enterprise, or activity: a residential zone.
		in the zone Informal In a state of focused attention or energy so that one's performance is enhanced: a goalie who was in the zone throughout the playoffs.
	www.bartleby.com /61/22/Z0022200.html (350 words)

	Zone melting -- Britannica Student Encyclopedia
		When a cylinder of a substance A containing an impurity B is melted and then slowly frozen from one end to the other, as in, the impurity is usually concentrated in the last-to-freeze region of the cylinder.
		Temperatures in the plasma zone range from 20,000° to 50,000° F (11,000° to 28,000° C).
		The melt around the seed is cooled, and its molecules attach themselves to the seed.
	www.britannica.com /ebi/article-9314321 (778 words)

	Polymer Engineering and Science: A Two-Zone Melting Model for Polymer Blends in a Batch Mixer.@ HighBeam Research (Site not responding. Last check: 2007-10-20)
		A two-zone model was developed to describe the rate of melting of the polymer pellets of mixtures of two semicrystalline polymers in an internal batch mixer.
		The mixing chamber was divided into two zones: high temperature and high shear zone, and low temperature and low shear zone.
		Melting was assumed to occur mainly in the first zone.
	www.highbeam.com /library/doc0.asp?DOCID=1G1:76781572&refid=holomed_1 (197 words)

	Chemistry 754 Notes — Lecture 1
		Decreasing the speed with which the crystal is pulled from the melt, increases the quality of the crystals (fewer defects) but decreases the growth rate.
		In general this method is not suitable for incongruently melting compounds, and of course the need for a seed crystal of the same composition limits its use as tool for exploratory synthetic research.
		Simple method for growing crystals of congruently melting compounds, when used in conjunction with low melting fluxes can be used to grow crystals at low temperature.
	www.chemistry.ohio-state.edu /~woodward/Lect3_754.htm (1357 words)

	[No title] (Site not responding. Last check: 2007-10-20)
		Considering a vertical zone melting configuration a transition point from the steady state to an unsteady oscillatory behavior of the crystal melt was found by experiments.
		The thermal bouyancy-driven convection is the dominating mechanism in the zone melting configuration.
		Because of the axisymmetric geometry of the melting zone and the axisymmetric boundary conditions a comparison of the instationary three-dimensional model to a linear stability analysis of a two-dimensional axisymmetric solution is possible and will be discussed.
	www.zarm.uni-bremen.de /gamm98/num_abs/a850.html (108 words)

	Search Results for melting - Encyclopædia Britannica
		liquefaction of a solid accompanied by decomposition or by reaction with the melt to produce another solid and a liquid that differs in composition from the original solid.
		Melting of lake ice usually occurs first near the shorelines or near the mouths of streams.
		For example, adding lead to tin lowers the melting point of the tin-rich alloy, and adding tin to lead lowers the melting point of the...
	www.britannica.com /search?query=melting&submit=Find&source=MWTEXT (674 words)

	IPC 6 English version C30B !A-C30B 19/12
		Single-crystal growth from melt solutions using molten solvents (by normal or gradient freezing C 30 B 11/00; by zone-melting C 30 B 13/00; by crystal pulling C 30 B 15/00; on immersed seed crystal C 30 B 17/00; by liquid phase epitaxial growth C 30 B 19/00; under a protective fluid C 30 B 27/00)
		Mechanisms for rotating or moving either the melt or the crystal (flotation methods C 30 B 15/28) [3]
		Single-crystal growth on to a seed which remains in the melt during growth, e.g.
	www.wipo.int /classifications/fulltext/new_ipc/ipc6/ec30b.htm (836 words)

	Zone Melting Encyclopedia Article, Definition, History, Biography (Site not responding. Last check: 2007-10-20)
		Looking For zone melting - Find zone melting and more at Lycos Search.
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	encyclopedia.localcolorart.com /encyclopedia/Zone_melting (684 words)

	Energy Citations Database (ECD) - Energy and Energy-Related Bibliographic Citations (Site not responding. Last check: 2007-10-20)
		Compacts of boron powder, suitable for zone melting, were prepared by using boron trioxide as a binder.
		A prepared powder compact had satisfactory strength for handling and mounting in a fioating zone melting apparatus.
		The melted zone, heated with 3.5 megacycle r-f current, was passed toward the bottom end of the compact.
	www.osti.gov /energycitations/product.biblio.jsp?osti_id=4264616 (154 words)

	Encyclopedia: Iraq disarmament crisis timeline
		UN inspectors eventually leave when their safety is threatened, and the UN Security Council seems unwilling to support their efforts to enter the building with a threat of force.
		A No-Fly Zone, which prohibits the flights of Iraqi planes, is established in southern Iraq, south of latitude 32 degrees north.
		Iraq also starts military incursions into the demilitarized zone between Iraq and Kuwait and increases its military activity in the northern and southern No-Fly Zones.
	www.nationmaster.com /encyclopedia/Iraq-disarmament-crisis-timeline (2102 words)

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