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Parameter in plasma physics
The magnetic diffusivity controls the rate of magnetic field diffusion. Since its role in the evolution equation for the magnetic field is analogous to
Magnetic_diffusivity
Index of articles associated with the same name
different mediums. Diffusivity may refer to: Thermal diffusivity, diffusivity of heat Diffusivity of mass: Mass diffusivity, molecular diffusivity (often called
Diffusivity
Process in plasma physics
= 1 μ 0 σ {\textstyle \eta ={\frac {1}{\mu _{0}\sigma }}} is the magnetic diffusivity. When the inflow density is comparable to the outflow density, conservation
Magnetic_reconnection
The Magnetic Prandtl number (Prm) is a dimensionless quantity occurring in magnetohydrodynamics which approximates the ratio of momentum diffusivity (viscosity)
Magnetic_Prandtl_number
Dimensionless quantity in magnetohydrodynamics
{\displaystyle \eta } is the magnetic diffusivity. The mechanism by which the motion of a conducting fluid generates a magnetic field is the subject of dynamo
Magnetic_Reynolds_number
Concept in magnetohydrodynamics
Here η = 1 / μ 0 σ {\displaystyle \eta =1/\mu _{0}\sigma } is the magnetic diffusivity (in the literature, the electrical resistivity, defined as 1 / σ
Induction_equation
where u is the velocity of the fluid; B is the magnetic B-field; and η = 1/σμ is the magnetic diffusivity, which is the reciprocal of the product of the
Earth's_magnetic_field
Structure formed by diffuse material in orbital motion around a massive central body
than the magnetic diffusivity in the disk. However, numerical simulations and theoretical models show that the viscosity and magnetic diffusivity have almost
Accretion_disk
Mechanism by which a celestial body generates a magnetic field
is velocity, B is magnetic field, t is time, and η = 1 / ( σ μ ) {\displaystyle \eta =1/(\sigma \mu )} is the magnetic diffusivity with σ {\displaystyle
Dynamo_theory
Model of electrically conducting fluids
finite electron diffusivity ( η ≠ 0 {\displaystyle \eta \neq 0} ). This diffusivity leads to a break in the magnetic topology; magnetic field lines can
Magnetohydrodynamics
Law of electrical current and voltage
which can be confusing since it is the same notation used for the magnetic diffusivity defined as η = 1 / μ 0 σ {\displaystyle \eta =1/\mu _{0}\sigma }
Ohm's_law
Ratio of inertial to viscous forces acting on a liquid
example, temperature and magnetic fields. Replacement of the kinematic viscosity ν = μ/ρ in Re by the thermal or magnetic diffusivity results in respectively
Reynolds_number
Type of motion of magnetic fields
{1}{\mu _{0}\sigma }}} is the magnetic diffusivity. In some cases it is possible to neglect one of the terms in the magnetic diffusion equation. This is
Magnetic_diffusion
Method of utilizing water in magnetic resonance imaging
The diffusivity along the principal axis, λ1 is also called the longitudinal diffusivity or the axial diffusivity or even the parallel diffusivity λ∥.
Diffusion-weighted magnetic resonance imaging
Diffusion-weighted_magnetic_resonance_imaging
Medical imaging technique
Magnetic resonance imaging (MRI) is a medical imaging technique used in radiology to generate pictures of the anatomy and the physiological processes inside
Magnetic_resonance_imaging
Dimensionless quantity in plasma physics
typical length scale of the system, η {\displaystyle \eta } is the magnetic diffusivity and v A {\displaystyle v_{A}} is the Alfvén velocity of the plasma
Lundquist_number
Dimensionless number in fluid mechanics
\ \lambda } is the magnetic diffusivity. B 0 {\displaystyle \ B_{0}} and d {\displaystyle \ d} are a characteristic magnetic field and a length scale
Chandrasekhar_number
Theorem in magnetohydrodynamics
{u}}({\bf {x}},t)dt+{\sqrt {2\eta }}d{\bf {W}}(t)} in which η is magnetic diffusivity and W is the three-dimensional Gaussian white noise (see also Wiener
Alfvén's_theorem
Ratio of kinematic viscosity to thermal diffusivity
dynamicist Ludwig Prandtl. It is defined as the ratio of momentum diffusivity to thermal diffusivity. The Prandtl number is a ratio of physical properties that
Prandtl_number
Binary star in the constellation Cetus
MacDonald, James; et al. (June 2018). "The Magnetic Binary GJ 65: A Test of Magnetic Diffusivity Effects". The Astrophysical Journal. 860 (1): 15
Gliese_65
Spectroscopic technique based on change of nuclear spin state
Nuclear magnetic resonance (NMR) is a physical phenomenon in which nuclei in a strong constant magnetic field are disturbed by a weak oscillating magnetic field
Nuclear_magnetic_resonance
Atmospheric effect caused by the solar wind
preferentially aligned along the local direction of the magnetic field. Electrons are mainly responsible for diffuse and pulsating auroras have, in contrast, a smoothly
Aurora
propulsion, plasma wind Magnetic bottle Magnetic braking Magnetic cloud Magnetic confinement fusion Magnetic diffusivity Magnetic field Magnetic field oscillating
List of plasma physics articles
List_of_plasma_physics_articles
Highly aggressive brain tumor, mostly found in children
Diffuse midline glioma, H3 K27-altered (DMG) is a tumour that arises in midline structures of the brain, most commonly the brainstem, thalamus and spinal
Diffuse_midline_glioma
Magnetic effect in insulators between ferromagnets
magnetoresistance (TMR) is a magnetoresistive effect that occurs in a magnetic tunnel junction (MTJ), which is a component consisting of two ferromagnets
Tunnel_magnetoresistance
Type of nuclear fusion reactor
A magnetic mirror, also known as a magnetic trap or sometimes as a pyrotron, is a type of magnetic confinement fusion device used in fusion power to trap
Magnetic_mirror
Turbulence that concerns the regimes of magnetofluid flow at high Reynolds number
\eta } represents magnetic diffusivity. The third equation is the incompressibility condition. In the above equation, the magnetic field is in Alfvén
Magnetohydrodynamic turbulence
Magnetohydrodynamic_turbulence
Equation used to calculate the electromigration of ions in a fluid
{E}}} _{\text{Electromigration}}} where D {\displaystyle D} is the diffusivity of the chemical species, z {\displaystyle z} is the valence of ionic
Nernst–Planck_equation
Forms which matter can take
appear to diffuse within compartmentalized layers or micelles instead of freely as in a uniform liquid. Transition metal atoms often have magnetic moments
State_of_matter
Set of techniques to measure and visualize aspects of the nervous system
quantitative methods. Functional brain imaging techniques, such as functional magnetic resonance imaging (fMRI), are common in neuroimaging but rarely used in
Neuroimaging
Magnetic resonance imaging of the brain uses magnetic resonance imaging (MRI) to produce high-quality two- or three-dimensional images of the brain, brainstem
Magnetic resonance imaging of the brain
Magnetic_resonance_imaging_of_the_brain
Electricity generation by nuclear fusion
tritium inventory. Materials with the lowest bulk hydrogen solubility and diffusivity provide the optimal candidates for stable barriers. A few pure metals
Fusion_power
System of stars and interstellar matter
portion of the Laniakea Supercluster. Galaxies have magnetic fields of their own. A galaxy's magnetic field influences its dynamics in multiple ways, including
Galaxy
Body of interstellar clouds
This emission originates from high-velocity electrons oscillating within magnetic fields. Ant Nebula Barnard's Loop Boomerang Nebula Cat's Eye Nebula Crab
Nebula
Medical imaging technique
Magnetic resonance imaging (MRI) is a medical imaging technique mostly used in radiology and nuclear medicine in order to investigate the anatomy and physiology
Physics of magnetic resonance imaging
Physics_of_magnetic_resonance_imaging
Pump used to transport fluids by conversion of rotational kinetic energy
environments. Magnetically coupled pumps, or magnetic drive pumps, vary from the traditional pumping style, as the motor is coupled to the pump by magnetic means
Centrifugal_pump
to expand in all directions without rupture. Mass diffusivity: Ability of one substance to diffuse through another Plasticity: Ability of a material to
List_of_materials_properties
Star at the centre of the Solar System
The other is magnetic heating, in which magnetic energy is continuously built up by photospheric motion and released through magnetic reconnection in
Sun
Transport of dissolved species from the highest to the lowest concentration region
molecule diffusing through the pore. Under this condition, the collision with the pore walls becomes gradually more likely and the diffusivity is lower
Diffusion
Magnetic field within the Solar System
conductive, meaning the magnetic field lines and the plasma flows are effectively "frozen" together and the magnetic field cannot diffuse through the plasma
Interplanetary_magnetic_field
Solid-state electronics based on electron spin
is the study of the intrinsic spin of the electron and its associated magnetic moment, in addition to its fundamental electronic charge, in solid-state
Spintronics
Specialized technique associated with MRI
In vivo magnetic resonance spectroscopy (MRS) is a specialized technique associated with magnetic resonance imaging (MRI). Magnetic resonance spectroscopy
In vivo magnetic resonance spectroscopy
In_vivo_magnetic_resonance_spectroscopy
DuPont high-performance plastics brand
mechanical properties.[citation needed] Extensive tables of measured thermal diffusivity, specific heat capacity, and derived density, all as functions of temperature
Vespel
Periodic change in the Sun's activity
The Solar cycle, also known as the solar magnetic activity cycle, sunspot cycle, or Schwabe cycle, is a periodic 11-year change in the Sun's activity measured
Solar_cycle
Biomedical imaging technology
Cardiac magnetic resonance imaging (cardiac MRI, CMR), also known as cardiovascular MRI, is a magnetic resonance imaging (MRI) technology used for non-invasive
Cardiac magnetic resonance imaging
Cardiac_magnetic_resonance_imaging
Phenomena that occur when a superconductor is in contact with a non-superconductor
{\displaystyle T_{c}} is largest when the normal material is a metal with a large diffusivity rather than an insulator (I). Proximity-effect suppression of T c {\displaystyle
Proximity effect (superconductivity)
Proximity_effect_(superconductivity)
Devices that measure magnetic field strength using the Hall effect
which a voltage is produced proportional to one axial component of the magnetic field vector B. Hall sensors are used for proximity sensing, positioning
Hall_effect_sensor
Ejecta from the Sun's corona
protons embedded within its magnetic field. This magnetic field is commonly in the form of a flux rope, a helical magnetic field with changing pitch angles
Coronal_mass_ejection
Outermost layer of the Sun's atmosphere
filled with relatively hot, tenuous plasma that is structured by the solar magnetic field. The solar corona lies above the photosphere and chromosphere and
Solar_corona
Non-invasive therapeutic technique
Focused ultrasound can generate localized heating. Focusing can be guided by Magnetic Resonance Imaging (MRgFUS). These procedures generally use lower frequencies
Focused_ultrasound
Artifact in computational fluid dynamics
exhibits a higher diffusivity than the true medium. This phenomenon can be particularly egregious when the system should not be diffusive at all, for example
Numerical_diffusion
Passive two-terminal electrical component that stores energy in its magnetic field
is a passive two-terminal electrical component that stores energy in a magnetic field when an electric current flows through it. An inductor typically
Inductor
MRI technique to image nerves
Magnetic resonance neurography (MRN) is the direct imaging of nerves in the body by optimizing selectivity for unique MRI water properties of nerves. It
Magnetic resonance neurography
Magnetic_resonance_neurography
Matter and radiation in the space between the star systems in a galaxy
grains in cosmic dust grains. Astrophysical maser Diffuse interstellar band Fossil stellar magnetic field Heliosphere List of interstellar and circumstellar
Interstellar_medium
Thermal motion of liquid or gas particles at temperatures above absolute zero
N_{A}=-D_{AB}{\frac {dC_{A}}{dx}}} (only applicable for no bulk motion) where D is the diffusivity of A through B, proportional to the average molecular velocity and, therefore
Molecular_diffusion
Void between celestial bodies
plasma, permeated by electromagnetic radiation, cosmic rays, neutrinos, magnetic fields and dust. The baseline temperature of outer space, as set by the
Outer_space
Auroras located on Mars
Mars and are diffuse and often localized. Ever since their discovery, it has been an area of active research. Mars lacks a substantial magnetic field (see:
Aurora_on_Mars
Seventh planet from the Sun
Sun's particles. In comparison, the magnetic field of Earth is roughly as strong at either pole, and its "magnetic equator" is roughly parallel with its
Uranus
fusion Magnetic damping Magnetic deviation Magnetic diffusivity Magnetic dip Magnetic dipole Magnetic dipole–dipole interaction Magnetic domain Magnetic effective
Index_of_physics_articles_(M)
Magnetic confinement device used to produce thermonuclear fusion power
tokamak (/ˈtoʊkəmæk/; Russian: токамáк) is a machine which uses a powerful magnetic field generated by external magnets to confine plasma in the shape of an
Tokamak
Theoretical framework for strongly magnetized plasmas
Non-dimensional scaling of turbulence characteristics and turbulent diffusivity. Nuclear Fusion, 41(9):1235, 2001. G.G. Howes, S.C. Cowley, W. Dorland
Gyrokinetics
the radius of the spherical pore and D {\displaystyle D} is the bulk diffusivity. The connection between NMR relaxation measurements and petrophysical
Nuclear magnetic resonance in porous media
Nuclear_magnetic_resonance_in_porous_media
Distance over which a quantity decreases by a factor of e
(August 1998). "Disc structure around strongly magnetic accretors: a full disc solution with turbulent diffusivity". Monthly Notices of the Royal Astronomical
Scale_height
Device used to direct the flow of a fluid
desirable. Magnetic nozzles have also been proposed for some types of propulsion, such as VASIMR, in which the flow of plasma is directed by magnetic fields
Nozzle
First planet from the Sun
of the magnetic field are stable. It is likely that this magnetic field is generated by a dynamo effect, in a manner similar to the magnetic field of
Mercury_(planet)
Vacuum tube used to display images
green, and blue). In modern CRT monitors and TVs the beams are bent by magnetic deflection, using a deflection yoke. Electrostatic deflection is commonly
Cathode_ray_tube
Symbols for constants, special functions
acceleration in physics the linear thermal expansion coefficient the thermal diffusivity In organic chemistry the α-carbon is the backbone carbon next to the
Greek letters used in mathematics, science, and engineering
Greek_letters_used_in_mathematics,_science,_and_engineering
Action to achieve a result in the delivery of healthcare
tomography Fluoroscopy Magnetic resonance imaging Diffuse optical imaging Diffusion tensor imaging Diffusion-weighted imaging Functional magnetic resonance imaging
Medical_procedure
Mathematical concept applicable to physics
integral of magnetic flux", in which case "electric flux" would instead be defined as "electric field" and "magnetic flux" defined as "magnetic field". This
Flux
Machine to increase pressure of gas by reducing its volume
extensively used in large refrigeration and air conditioning systems. Magnetic bearing (magnetically levitated) and air bearing centrifugal compressors exist. Many
Compressor
American brain imaging researcher
they were the first to demonstrate in human subjects the early drop in diffusivity seen in acute infarction in cats by Moseley. Consistent with his joint
Kenneth_Kwong
Magnetic confinement fusion device component
A magnetic divertor typically involves creating a separatrix-bounded magnetic topology using special magnetic coils. Particles and heat diffusing outward
Divertor
Problem in computer simulations of ideal magnetohydrodynamics
a form of numerical diffusion. In near-ideal MHD systems, the magnetic field diffuses only very slowly through the plasma or fluid of the system; its
Numerical_resistivity
Concentration gradient − ∇ c {\displaystyle -{\boldsymbol {\nabla }}c} Diffusivity D {\displaystyle {\boldsymbol {D}}} Flow in porous media Weighted fluid
Orthotropic_material
Dimensionless quantity in plasma physics
Mach number (also known as the Alfvén number, Alfvénic Mach number, and magnetic Mach number; MA or MM) is a dimensionless quantity representing the ratio
Alfvén_Mach_number
Type of transistor
A diffused junction transistor is a transistor formed by diffusing dopants into a semiconductor substrate. The diffusion process was developed later than
Diffused_junction_transistor
Smallest unit of a chemical element
materials have atoms with magnetic moments that line up in random directions when no magnetic field is present, but the magnetic moments of the individual
Atom
Disease of the lungs
signs of pneumonia, a lung abscess, or a tumor. Magnetic resonance imaging (MRI), also called nuclear magnetic resonance (NMR) scanning, uses powerful magnets
Pleurisy
Extension of endometrial tissue into the myometrium
non-invasive imaging techniques such as transvaginal ultrasonography (TVUS) and magnetic resonance imaging (MRI) can both be used to strongly suggest the diagnosis
Adenomyosis
Fluid flow that occurs due to heterogeneous fluid properties and body forces
difference across the medium. The general diffusivity, D {\displaystyle D} , is redefined as a thermal diffusivity, α {\displaystyle \alpha } . D = α {\displaystyle
Convection
Intentional introduction of impurities into an intrinsic semiconductor
similar atomic radius to silicon, high concentrations can be achieved. Its diffusivity is about a tenth of phosphorus or boron, so it is used where the dopant
Doping_(semiconductor)
Type of magnetometer
extremely weak magnetic fields, based on superconducting loops containing Josephson junctions. SQUIDs are sensitive enough to measure magnetic fields as low
SQUID
Technique in chemistry and manufacturing
ion-exchange membrane or a salt bridge) is optional to keep the products from diffusing to the vicinity of the opposite electrode. The electrolyte is a chemical
Electrolysis
Quantum physical phenomenon
{\displaystyle H_{\text{S}}} is magnetic scattering, and H SO {\displaystyle H_{\text{SO}}} is spin–orbit scattering. For a non-magnetic sample ( H S = 0 {\displaystyle
Weak_localization
Pulse sequence during a medical test
An MRI pulse sequence in magnetic resonance imaging (MRI) is a particular setting of pulse sequences and pulsed field gradients, resulting in a particular
MRI_pulse_sequence
Sixth planet from the Sun
magnetic field, which is weaker than Earth's, but has a magnetic moment 580 times that of Earth because of Saturn's greater size. Saturn's magnetic field
Saturn
Mathematical parameter used to describe planetary magnetic field lines
of planetary magnetic field lines. Colloquially, L-value often describes the set of magnetic field lines which cross the Earth's magnetic equator at a
L-shell
Geological concept
Concentration gradient − ∇ c {\displaystyle -{\boldsymbol {\nabla }}c} Diffusivity D {\displaystyle {\boldsymbol {D}}} Flow in porous media Weighted fluid
Transverse_isotropy
Type of bipolar junction transistor
diffused-base transistor. The Philco micro-alloy diffused transistor had a mechanical weakness that ultimately limited their speed; the thin diffused
Alloy-junction_transistor
Synthetic polymer
environments, where it is used for lining containers, as a coating for magnetic stirrers, and as tubing for highly corrosive chemicals such as hydrofluoric
Polytetrafluoroethylene
Discrete device in an electronic system
Logic gate Microcontroller Analog circuit Hall-effect sensor – senses a magnetic field Current sensor – senses a current through it Programmable logic device
Electronic_component
Medical diagnostic method
Diffuse optical mammography, or simply optical mammography, is an emerging imaging technique that enables the investigation of the breast composition
Diffuse_optical_mammography
Concept in materials science
{J\centerdot J}{c}}dA} , where D s o l {\displaystyle D_{sol}} is the diffusivity of the solute atom in the host material, Ω {\displaystyle \Omega } is
Cottrell_atmosphere
Shielding an object from view using materials made to redirect light
electric and magnetic fields of a radiated light source respectively, among other descriptions. The precise degree of electric and magnetic response can
Metamaterial_cloaking
Technique and process of creating visual representations of the interior of a body
types of colon cancer.[citation needed] A magnetic resonance imaging instrument (MRI scanner), or "nuclear magnetic resonance (NMR) imaging" scanner as it
Medical_imaging
Term to describe all brain white-matter diseases
Fattal-Valevski, A.; Kolodny, E. H. (2006). "Leukodystrophies". Topics in Magnetic Resonance Imaging. 17 (4): 219–242. doi:10.1097/RMR.0b013e31804c99d4. PMID 17414998
Leukoencephalopathy
malignant Imaging studies, which includes many medical imaging techniques Magnetic resonance imaging (MRI), a non-invasive method to render images of living
Biological_imaging
Visual illusion
optic neuritis. Phosphenes can be induced by mechanical, electrical, or magnetic stimulation of the retina or visual cortex, or by random firing of cells
Phosphene
Nuclear magnetic resonance (NMR) logging is a type of well logging that uses the NMR response of a formation to directly determine its porosity and permeability
Nuclear magnetic resonance logging
Nuclear_magnetic_resonance_logging
Device for generating microwaves
generates microwaves using the interaction of a stream of electrons with a magnetic field, while moving past a series of cavity resonators, which are small
Cavity_magnetron
MAGNETIC DIFFUSIVITY
MAGNETIC DIFFUSIVITY
Boy/Male
Hindu, Indian, Telugu, Traditional
A Moon which has Magnetic Power; Loved by the Moon
Girl/Female
Tamil
Noyonika | நோயோநீகா
Beautiful eyes that induce magnetism, One with expressive eyes
Noyonika | நோயோநீகா
Girl/Female
Hindu
Beautiful eyes that induce magnetism, One with expressive eyes
Boy/Male
Tamil
Magnet
Girl/Female
Tamil
Nayanika | நாயாநீகா
Beautiful eyes that induce magnetism, One with expressive eyes
Nayanika | நாயாநீகா
Girl/Female
Hindu
Beautiful eyes that induce magnetism, One with expressive eyes
Boy/Male
Hindu
Magnet
Girl/Female
Hindu
Beautiful eyes that induce magnetism, One with expressive eyes
Girl/Female
Indian, Tamil
The Sun is the Star at the Centre of the Solar System; It is Almost Perfectly Spherical and Consists of Hot Plasma Interwoven with Magnetic Fields; Sun
Girl/Female
Tamil
Nayonika | நயோநிகா
Beautiful eyes that induce magnetism, One with expressive eyes
MAGNETIC DIFFUSIVITY
MAGNETIC DIFFUSIVITY
Boy/Male
Australian, German
Noteworthy and Valorous
Boy/Male
Hindu, Indian, Punjabi, Sikh
Embodiment of Lord's Name
Boy/Male
Assamese, Bengali, Hindu, Indian, Marathi, Sanskrit, Sindhi, Tamil, Thai
Joy; Happiness
Boy/Male
Indian, Kannada, Traditional
Religious
Boy/Male
Indian, Punjabi, Sikh
True Love of God
Girl/Female
Muslim
Flower
Boy/Male
Muslim/Islamic
Servant of the Kind
Girl/Female
Hindu, Indian
Having Food
Boy/Male
Muslim
Merciful heart
Girl/Female
Hindu
Having control upon all abilities
MAGNETIC DIFFUSIVITY
MAGNETIC DIFFUSIVITY
MAGNETIC DIFFUSIVITY
MAGNETIC DIFFUSIVITY
MAGNETIC DIFFUSIVITY
a.
Of or pertaining to, or characterized by, the earth's magnetism; as, the magnetic north; the magnetic meridian.
n.
The science which treats of magnetic phenomena.
v. t.
To attract as a magnet attracts, or like a magnet; to move; to influence.
a.
Pertaining to the magnet; possessing the properties of the magnet, or corresponding properties; as, a magnetic bar of iron; a magnetic needle.
a.
Pertaining to, or containing, magnesium; as, magnesic oxide.
a.
Alt. of Magnetical
v. t.
To communicate magnetic properties to; as, to magnetize a needle.
n.
An oxide of iron (Fe3O4) occurring in isometric crystals, also massive, of a black color and metallic luster. It is readily attracted by a magnet and sometimes possesses polarity, being then called loadstone. It is an important iron ore. Called also magnetic iron.
a.
Pertaining to, or inhabiting, the Ganges; as, the Gangetic shark.
v. t.
To bring under the influence of animal magnetism.
v. t.
To deprive of magnetic properties. See Magnetize.
n.
The property, quality, or state, of being magnetic; the manifestation of the force in nature which is seen in a magnet.
n.
A magnet.
a.
Having, susceptible to, or induced by, animal magnetism, so called; as, a magnetic sleep. See Magnetism.
a.
Capable of becoming a magnet; susceptible to magnetism; as, the magnetic metals.
n.
A piece of magnetic iron ore possessing polarity like a magnetic needle. See Magnetite.
n.
The science of magnetism.
a.
Pertaining to, or characterized by, electricity by the action of magnets; as, magneto-electric induction.
n.
One versed in magnetism.
n.
Any metal, as iron, nickel, cobalt, etc., which may receive, by any means, the properties of the loadstone, and which then, when suspended, fixes itself in the direction of a magnetic meridian.