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The zone melting process developed by William Gardner Pfann was used to produce pure germanium, and subsequently float-zone silicon became available when Henry Theuerer of Bell Labs adapted Pfann's method to silicon.
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zone and melting
So-called structure zone models were developed to describe the micro structure and ceramics of thin films as a function of the homologous temperature T < sub > h </ sub > that is the ratio of deposition temperature over melting temperature.
Zone distillation is a distillation process in long container with partial melting of refined matter in moving liquid zone and condensation of vapor in the solid phase at condensate pulling in cold area.
This debris can accumulate due to ice flow toward the surface in the ablation zone, melting of surface ice or from debris that falls onto the glacier from valley sidewalls.
Individual plutons are crystallized from magma that traveled toward the surface from a zone of partial melting near the base of the Earth's crust.
Because subduction of slabs to depth is necessary to drive subduction zone volcanism ( through the destabilization and dewatering of minerals and the resultant flux melting of the mantle wedge ), flat-slab subduction can be invoked to explain volcanic gaps.
Zone melting ( or zone refining or floating zone process ) is a group of similar methods of purifying crystals, in which a narrow region of a crystal is molten, and this molten zone is moved along the crystal ( in practice, the crystal is pulled through the heater ).
A variety of heaters can be used for zone melting, with their most important characteristic being the ability to form short molten zones that move slowly and uniformly through the ingot.
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.
The term ' induction coil ' is also used for a coil carrying high-frequency alternating current ( AC ), producing eddy currents to heat objects placed in the interior of the coil, in induction heating or zone melting equipment.
The ablation zone of the Gangotri glacier is covered by a thick pile of supraglacial moraines and is characterized by several ice sections, melting into pools of supraglacial lakes.
; < span id =" ablation_zone "> Ablation zone </ span >: The area of a glacier where yearly melting meets or exceeds the annual snow fall.
In the subduction zone, loss of volatiles from the subducted slab induces partial melting of the overriding mantle.
Diorite results from partial melting of a mafic rock above a subduction zone.
It can be done by partial melting of a solid, for example in zone refining of silicon or metals, or by partial crystallization of a liquid, for example " freeze distillation ", also called " normal freezing " or " progressive freezing ".
It is a critical parameter for purification using zone melting, and determines how effective an impurity can be removed using directional solidification, described by the Scheil equation.
In the subduction zone, loss of water from the subducted slab induces partial melting of the overriding mantle and generates low-density, calc-alkaline magma that buoyantly rises to intrude and be extruded through the lithosphere of the overriding plate.
The landing zone consists of a controlled array of nanometer-level ' bumps ' on the disk surface produced during manufacturing of the disk using a local substrate melting process employing suitable laser-based equipment.
Rock considered lamprophyres to be derived from deep, volatile-driven melting in a subduction zone setting.
Boninite magmatism is similar to komatiite magmatism but is driven more by melting induced by volatile flows above a subduction zone than by decompression melting.
The start of the cycle can be placed at the mid-ocean divergent boundaries where new magma is produced by mantle upwelling and a shallow melting zone.
The role of water and other volatiles in the melting of existing crustal rock in the wedge above a subduction zone is a most important part of the cycle.
zone and process
Some species in the Plethodontidae have a weak zone at the base of the tail and if the salamander is in danger or if the tail is grabbed by a predator, it breaks off, a process known as autotomy.
This process steadily concentrates salt in the root zone, decreasing productivity for crops that are not salt-tolerant.
Impurity distribution in the condensate is described by known equations of zone recrystallization with various numbers of iteration of process – with replacement distribution efficient k of crystallization on separation factor α of distillation.
Nations who recognize the Council as the government of Libya may not have to go through the process of obtaining UN security council's approval to establish a " No-fly zone " if the Council requests one, as this could count as a " friendly request ".
Fully differentiated neurons are permanently postmitotic ; however, recent research shows that additional neurons throughout the brain can originate from neural stem cells found throughout the brain but in particularly high concentrations in the subventricular zone and subgranular zone through the process of neurogenesis.
It is an undesired intermediate product in thorium-based nuclear reactors and is therefore removed from the active zone of the reactor during the breeding process.
When European imperialism brought a new phase in Southeast Asian commerce in the late 1800s, Thailand ( known then as Siam ) was able to maintain its independence as a buffer zone between British-controlled Burma to the west and French-dominated Indochina to the east, but losing over 50 % of its territory in the process.
The outer zone is the area where the flame is the hottest and the oxidation process is complete.
The formation of important ore minerals may occur by the process of metasomatism at or near the contact zone.
The weld itself is called the fusion zone — more specifically, it is where the filler metal was laid during the welding process.
Phytoplankton obtain energy through the process of photosynthesis and must therefore live in the well-lit surface layer ( termed the euphotic zone ) of an ocean, sea, lake, or other body of water.
Therefore, these processes are also known as Umklapp ( U ) processes and can only occur when phonons with sufficiently large q-vectors are excited, because unless the sum of q < sub > 2 </ sub > and q < sub > 3 </ sub > points outside of the Brillouin zone the momentum is conserved and the process is normal scattering ( N-process ).
In this process the temporary layer called preplate is split into the marginal zone on the top and subplate below, and the space between them is populated by neuronal layers in the inside-out pattern.
This process is operative beneath and behind the inner walls of oceanic trenches ( subduction zone ) where slices of oceanic crust and mantle are ripped from the upper part of the descending plate and wedged and packed in high pressure assemblages against the leading edge of the other plate.
A similar process of cell separation caused by the breakdown of pectin occurs in the abscission zone of the petioles of deciduous plants at leaf fall.
This anomaly might be caused by a diffusion process that has transported some of the helium and heavier elements out of the photosphere and into a region below the star's convection zone.
A high-purity ( 99. 999 % = Nines ( engineering ) | 5N ) tantalum single crystal, made by the floating zone process ( cylindrical object in the center )
This process is also known as the float zone process, particularly in semiconductor materials processing.
zone and developed
Later it developed that the Soviets had a very different interpretation of democracy, which will be discussed later, and their judgment never told them that the Big Three should unite in establishing democratic conditions, as we understand them, within their zone of influence.
In the case of the San Andreas fault continental transform, many earthquakes occur away from the plate boundary and are related to strains developed within the broader zone of deformation caused by major irregularities in the fault trace ( e. g., the " Big bend " region ).
The unusually wide zone of coseismic damage caused by the 2001 Kunlun earthquake has been attributed to the effects of the sonic boom developed in such earthquakes.
The mercantile zone was so highly developed that wool had to be imported from Scotland and England.
The ideas on the zone of development were later developed in a number of psychological and educational theories and practices.
In the fall of 2006, researchers developed and installed an " autonomous observatory " using robotic video cameras with image processing software that detects and records high resolution video of birds in flight inside a high probability zone in the Cache River area.
The Fagnano Lake occupies an glacier-carved depression in a pull-apart basin developed along the Magallanes-Fagnano Fault zone.
* In 2003 the 12 year self-government in Iraqi Kurdistan ends, developed under the protection of the UN " No-fly zone " during the now-ousted Saddam Hussein regime.
More significantly, many beaches are a discharge zone for untreated sewage in most underdeveloped countries ; even in developed countries beach closure is an occasional circumstance due to sanitary sewer overflow.
In addition to differences in internal pressure, these organisms have developed a different balance between their metabolic reactions from those organisms that live in the epipelagic zone.
Lilacs are popular shrubs in parks and gardens throughout the temperate zone, and several hybrids and numerous cultivars have been developed.
The Winstanley and York Road council estates have developed a reputation for drug related offences, and were made part of a zero-tolerance " drug exclusion zone " in 2007.
If however, a large tract of ocean intervenes between the continental margin the subduction zone, a fully developed arc and back arc basin ( Fig 1D ) may eventually arrive and collide with the continental margin.
Along the shores of the canal a large industrial zone has developed, which made the three municipalities one urban area.
The Hall of the Abencerrajes ( c. 1333-1391 ) and the Hall of the two Sisters ( c. 1333-1354 ) are extraordinarily developed examples of muqarnas domes, taking the tradition of the squinch in Islamic architecture from a functional element in the zone of transition to a highly ornamental covering for the dome itself.
Recently the campus also developed a Wi-Fi zone with internet access.
In the 19th century as Cairo expanded, Wagh El-Birket developed as a contact zone between the wealthy area round the Azbakeya lake and expanding central Cairo.
A large industrial zone developed on the outskirts of residential Talpiot to house the businesses evicted from Mamilla.
The arrival of the Maritime Bell Beaker from the west a century or two later initiated a period of borrowing and experimentation in what has been called the Primary Bell Beaker / Corded Ware contact zone and cultural traits developed here, such as single burial and the shaft-hole axe, were transmitted westwards along the exchange networks from the Rhine to the Loire.
The zone has a developed area of 7 square kilometers.
Arthur Tansley developed this idea with the " polyclimax " -- multiple steady-state end-points, determined by edaphic factors, in a given climatic zone.
The CHA has developed a Sea Angling zone on the outer breakwater arm.
Some attempts were made at mitigation work at the time, but with hindsight they were both inappropriate and inadequate and large blocks of gorse ( Ulex europeaus ) developed in the zone of disturbance on either side of the motorway creating further fragmentation of the site and causing serious fire risks.
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