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| [[File:Magnetization curves.svg|thumb|Magnetization curves of 9 ferromagnetic materials, showing saturation. 1.Sheet steel, 2.Silicon steel, 3.Cast steel, 4.Tungsten steel, 5.Magnet steel, 6.Cast iron, 7.Nickel, 8.Cobalt, 9.Magnetite<ref>{{cite manual|first=Charles |last=Steinmetz |year=1917|title=Theory and Calculation of Electric Circuits |publisher=McGraw-Hill|ref=harvnb|section=fig. 42}}</ref>]]
| | Research has shown that since the amygdala gives more weight to NEGATIVE, painful experiences than positive ones, that in order for a marriage or relationship to last, you must create 4 positive experiences for each negative one. Most of the time your dog acts out in destructive ways not because you are gone but because he is bored. After you get done reading you will know that anxiety does not have to take over your life. You don't have to suffer from anxiety - cures are easier and faster than you might think. Courage is a constructive way of thinking before acting making us being alive at all times and not allowing ourselves to go on autopilot. <br><br>The first, Capgras Delusion, is characterized by the patient being convinced a close family member or friend is an imposter. Once you feel the anxiety starting to take hold, play your favorite tunes. Social phobias or anxiety can lead a teen into seclusion, isolation and emotional torment. It is fine to tune in to the latest news developments once a day, but you want to avoid feeding your anxieties with a steady stream of disheartening and threatening news throughout the course of the day. By giving you the tools you need to deal with situations in a different manner, the anxious thoughts do not creep in and control your every move like with other remedies. <br><br>A certain humming sound or a continuous sound can make the person lose his balance. Considering medication can make adverse reactions, various most people with anxiety disorder are afraid to take them owing to anxieties about brief and long phrase facet outcomes. The Valerian root in the tea decreased my anxiety like nothing I had ever found. It is just your body's reaction to fear and flight that you are experiencing. If there is nothing you can do, will yourself to stop worrying and even thinking about whatever worries you. <br><br>Most people wouldn't even have to change what they eat, they would just have to change their portions. ' Only those couple between the ages of 30 and 50 may adopt kids. Social Anxiousness is often just the starting of an anxiety problem and will frequently conclude up in a state of depression. On the net anxiety forums you'll notice a full variety of sections. Lastly, people will demand for the root causes of all these anxiety conditions. <br><br>So, a family member is saying they are feeling anxious, or they are already having a full-blown panic attack. and Magnus Simrén 'Efficient diagnosis of suspected functional bowel disorders'. Initially, you may really feel nervous taking SSRIs, however the feeling typically disappears after a few weeks. Before you hit the sheets at night, you should think about all of the great stuff that is occurring in your life right now. The need for you to recognize how to prevent and deal with anxiety attack cannot be exaggerated.<br><br>If you liked this article so you would like to obtain more info with regards to [http://www.stress-lavoro-correlato.info/sitemap/ what is the best anxiety medication] nicely visit the web page. |
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| Seen in some [[magnetic]] materials, '''saturation''' is the state reached when an increase in applied external [[magnetic field]] ''H'' cannot increase the [[magnetization]] of the material further, so the total [[magnetic flux density]] ''B'' levels off. It is a characteristic particularly of [[ferromagnetic]] materials, such as [[iron]], [[nickel]], [[cobalt]] and their alloys.
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| ==Description==
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| Saturation is most clearly seen in the ''magnetization curve'' (also called ''BH'' curve or [[hysteresis]] curve) of a substance, as a bending to the right of the curve (see graph at right). As the ''H'' field increases, the ''B'' field approaches a maximum value [[asymptote|asymptotically]], the saturation level for the substance. Technically, above saturation, the ''B'' field continues increasing, but at the [[paramagnetic]] rate, which is 3 [[Orders of magnitude (magnetic field)|orders of magnitude]] smaller than the ferromagnetic rate seen below saturation.<ref name=Bozorth>{{cite book
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| |last = Bozorth
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| |first = Richard M.
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| |title = Ferromagnetism
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| |publisher = [[Wiley-IEEE Press]]
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| |year = 1993
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| |origyear = Reissue of 1951 publication
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| |series = AN IEEE Press Classic Reissue
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| |isbn = 0-7803-1032-2
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| |ref = harvnb
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| }}</ref>
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| The relation between the [[magnetizing field]] ''H'' and the [[magnetic field]] ''B'' can also be expressed as the magnetic [[Permeability (electromagnetism)|permeability]]: <math>\mu = B / H</math> or the ''relative permeability'' <math>\mu_r = \mu/\mu_0</math>, where <math>\mu_0</math> is the [[vacuum permeability]]. The permeability of ferromagnetic materials is not constant, but depends on ''H''. In saturable materials the relative permeability increases with ''H'' to a maximum, then as it approaches saturation inverts and decreases toward one.<ref name=Bozorth/><ref>{{cite book
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| | last = Bakshi
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| | first = V.U.
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| | authorlink =
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| | coauthors = U.A.Bakshi
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| | title = Basic Electrical Engineering
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| | publisher = Technical Publications
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| | year = 2009
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| | location =
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| | pages = 3.31
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| | url = http://books.google.com/books?id=N9hnAJxFcaEC&pg=SA3-PA31&dq=ferromagnetic+permeability+above+saturation&hl=en&ei=0g6dTtajLu3YiQL4sa3nCQ&sa=X&oi=book_result&ct=result&resnum=10&ved=0CFwQ6AEwCQ#v=onepage&q=ferromagnetic%20permeability%20above%20saturation&f=false
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| | doi =
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| | pages=3-31
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| | isbn = 81-8431-334-9}}</ref>
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| Different materials have different saturation levels. For example, high permeability iron alloys used in transformers reach magnetic saturation at 1.6 - 2.2 [[tesla (unit)|tesla]]s (T),<ref>{{cite book|editor1-last=Laughton|editor1-first=M. A.|editor2-last=Warne|editor2-first=D. F.|title=Electrical Engineer's Reference Book|edition= Sixteenth|publisher=Newnes|year=2003|isbn=0-7506-4637-3|ref=harvnb|chapter=8}}</ref> whereas [[ferrite magnet|ferrite]]s saturate at 0.2 - 0.5 T.<ref name=Chikazumi>{{cite manual
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| |last = Chikazumi
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| |first = Sōshin
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| |title = Physics of Ferromagnetism
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| |publisher = [[Clarendon Press]]
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| |year = 1997
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| |isbn = 0-19-851776-9
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| |ref = harvnb
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| |section=table 9.2
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| }}</ref> Some [[amorphous metal|amorphous]] alloys saturate at 1.2-1.3 T.<ref>{{cite patent
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| | country = USA
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| | number = 5126907
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| | title = Thin film magnetic head having at least one magnetic core member made at least partly of a material having a high saturation magnetic flux density
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| | gdate = 1992
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| | inventor = Yoshihiro Hamakawa, Hisashi Takano, Naoki Koyama, Eijin Moriwaki, Shinobu Sasaki, Kazuo Shiiki
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| | ref=harvnb
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| }}</ref> [[Mu metal]] saturates at around 0.8 T.<ref>{{cite web|url=http://www.kjmagnetics.com/blog.asp?p=shielding-materials|title=Shielding Materials|publisher=K+J Magnetics|accessdate=2013-05-07}}</ref><ref>{{cite web|url=http://mumetal.co.uk/2009/04/03/mumetal-is-one-of-a-family-of-three-nickel-iron-alloys/|title=Mumetal is one of a family of three Nickel-Iron alloys|publisher=mumetal.co.uk|accessdate=2013-05-07}}</ref>
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| [[File:Permeability of ferromagnet by Zureks.svg|thumb|Due to saturation, the [[magnetic permeability]] μ<sub>f</sub> of a ferromagnetic substance reaches a maximum and then declines]]
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| ==Explanation==
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| {{Further2|[[Ferromagnetism]]}}
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| Ferromagnetic materials (like iron) are composed of microscopic regions called [[magnetic domain]]s, that act like tiny [[permanent magnet]]s that can change their direction of magnetization. Before an external magnetic field is applied to the material, the domains are oriented in random directions. Their tiny [[magnetic field]]s are oriented in random directions and cancel each other out, so the material has no significant magnetic field. When an external magnetizing field ''H'' is applied to the material, it penetrates the material and aligns the domains, causing their tiny magnetic fields to turn and align parallel to the external field, adding together to create a large magnetic field ''B'' which extends out from the material. This is called [[magnetization]]. The stronger the external magnetic field ''H'', the more the domains align yielding a higher magnetic flux density ''B''. Saturation occurs when practically all the domains are lined up, so further increases in ''H'' can't increase ''B'' beyond the increment that would be caused in a nonmagnetic material, in other words, cannot cause further alignment of the domains.
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| ==Effects and uses==
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| Saturation limits the maximum magnetic fields achievable in ferromagnetic-core [[electromagnet]]s and [[transformer]]s to around 2 T, which puts a limit on the minimum size of their cores. This is one reason why high power motors, generators, and [[Electric utility|utility]] transformers are physically large; because they must have large magnetic cores.
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| In [[electronic circuit]]s, transformers and [[inductor]]s with ferromagnetic cores operate [[Linear circuit|nonlinearly]] when the current through them is large enough to drive their core materials into saturation. This means that their [[inductance]] and other properties vary with changes in drive current. In [[linear circuit]]s this is usually considered an unwanted departure from ideal behavior. When [[Alternating current|AC]] [[Signal (circuit theory)|signals]] are applied, this nonlinearity can cause the generation of [[harmonic]]s and [[intermodulation distortion]]. To prevent this, the level of signals applied to iron core inductors must be limited so they don't saturate. To lower its effects, an air gap is created in some kinds of transformer cores.<ref>{{cite web |url=http://sound.westhost.com/xfmr2.htm#s131 |title=Transformers - The Basics (Section 2) |first=Elliott |last= Rod |date=May 2010 |work= Beginner's Guide to Transformers|publisher= Elliott Sound Products |accessdate=2011-03-17| ref=harvnb}}</ref> The ''saturation current'', the current through the winding required to saturate the magnetic core, is given by manufacturers in the specifications for many inductors and transformers.
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| On the other hand, saturation is exploited in some electronic devices. Saturation is employed to limit current in ''saturable-core transformers'', used in [[arc welding]], and ferroresonant transformers which serve as [[voltage regulator]]s. When the primary current exceeds a certain value, the core is pushed into its saturation region, limiting further increases in secondary current. In a more sophisticated application, [[saturable core inductor]]s and [[magnetic amplifier]]s use a DC current through a separate winding to control an inductor's [[Electrical impedance|impedance]]. Varying the current in the control winding moves the operating point up and down in the saturation curve, controlling the AC current through the inductor. These are used in variable [[fluorescent light]] [[ballast (electrical)|ballast]]s, and power control systems.<ref>{{cite manual
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| |last = Choudhury
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| |first = D. Roy
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| |title = Modern Control Engineering
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| |publisher = Prentice-Hall of India
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| |year = 2005
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| |isbn = 81-203-2196-0
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| |ref = harvnb
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| |section=2.9.1}}</ref>
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| <!-- Any physicist cares to say more? -->
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| ==See also==
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| * [[Ferromagnetism]]
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| * [[Magnetic domain]]
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| * [[Magnetic reluctance]]
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| * [[Permeability (electromagnetism)|Permeability]]
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| * [[Permendur|Permendur/Hiperco]]
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| ==References==
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| {{Reflist}}
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| {{DEFAULTSORT:Saturation (Magnetic)}}
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| [[Category:Magnetism]]
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Research has shown that since the amygdala gives more weight to NEGATIVE, painful experiences than positive ones, that in order for a marriage or relationship to last, you must create 4 positive experiences for each negative one. Most of the time your dog acts out in destructive ways not because you are gone but because he is bored. After you get done reading you will know that anxiety does not have to take over your life. You don't have to suffer from anxiety - cures are easier and faster than you might think. Courage is a constructive way of thinking before acting making us being alive at all times and not allowing ourselves to go on autopilot.
The first, Capgras Delusion, is characterized by the patient being convinced a close family member or friend is an imposter. Once you feel the anxiety starting to take hold, play your favorite tunes. Social phobias or anxiety can lead a teen into seclusion, isolation and emotional torment. It is fine to tune in to the latest news developments once a day, but you want to avoid feeding your anxieties with a steady stream of disheartening and threatening news throughout the course of the day. By giving you the tools you need to deal with situations in a different manner, the anxious thoughts do not creep in and control your every move like with other remedies.
A certain humming sound or a continuous sound can make the person lose his balance. Considering medication can make adverse reactions, various most people with anxiety disorder are afraid to take them owing to anxieties about brief and long phrase facet outcomes. The Valerian root in the tea decreased my anxiety like nothing I had ever found. It is just your body's reaction to fear and flight that you are experiencing. If there is nothing you can do, will yourself to stop worrying and even thinking about whatever worries you.
Most people wouldn't even have to change what they eat, they would just have to change their portions. ' Only those couple between the ages of 30 and 50 may adopt kids. Social Anxiousness is often just the starting of an anxiety problem and will frequently conclude up in a state of depression. On the net anxiety forums you'll notice a full variety of sections. Lastly, people will demand for the root causes of all these anxiety conditions.
So, a family member is saying they are feeling anxious, or they are already having a full-blown panic attack. and Magnus Simrén 'Efficient diagnosis of suspected functional bowel disorders'. Initially, you may really feel nervous taking SSRIs, however the feeling typically disappears after a few weeks. Before you hit the sheets at night, you should think about all of the great stuff that is occurring in your life right now. The need for you to recognize how to prevent and deal with anxiety attack cannot be exaggerated.
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