භෞතික විද්යාවෙහි සහ රසායන විද්යාවෙහි, ප්ලාස්මා යනු වායුවක අංශු කිසියම් ප්රමාණයක් අයනීකෘත වූ විට නිමැවෙන පදාර්ථයේ අවස්ථාවකි.
![image](https://www.wiki-data.si-lk.nina.az/image/aHR0cHM6Ly93d3cud2lraS1kYXRhLnNpLWxrLm5pbmEuYXovaW1hZ2UvYUhSMGNITTZMeTkxY0d4dllXUXVkMmxyYVcxbFpHbGhMbTl5Wnk5M2FXdHBjR1ZrYVdFdlkyOXRiVzl1Y3k5MGFIVnRZaTh5THpJMkwxQnNZWE50WVMxc1lXMXdYekl1YW5Cbkx6TXdNSEI0TFZCc1lYTnRZUzFzWVcxd1h6SXVhbkJuLmpwZw==.jpg)
ප්ලාස්මා අවස්ථාවේදී අයනීකෘත වායුවක් වන අතර ඉලෙක්ට්රෝනයක යම් අනුපාතයක් නිදහස් වන අතර ඒවා පරමාණුවකට හෝ අණුවක් වෙතට බැඳී ඇත. ධනාත්මක හා සෘණ ආරෝපණ තරමක් ස්වාධීනව ගමන් කිරීමට හැකියාව ඇති විද්යුත් චුම්බක ක්ෂේත්රයට දැඩි ලෙස ප්රතිචාර දැක්වීමට ප්ලාස්මා විදුලිය සන්නායක වේ. එබැවින් ප්ලාස්මා ඝන ද්රව්ය, ද්රව හෝ වායූන් මෙන් නොව එහි ද්රව්යමය තත්වයක් ලෙස සැලකේ. ප්ලාස්මා සාමාන්යයෙන් උදාසීන වායු වළාකුළු ආකාරයක් (උදා. තරු) උදා වේ.
ඉතිහාසය
මෙම පදාර්ථය පළමු වරට ක්ෲක්ස් නලයක් තුළ මුලින්ම හදුනාගත් අතර 1879 දී ශ්රීමත් විලියම් ක්රූකොස් විසින් විස්තර කරන ලදී (ඔහු එය "විකිරණමය පදාර්ථයයි" ලෙස හැඳින්වේ.) [1] ක්රූකොස් නාලය "කැතෝඩ කිරණ" යන පදාර්ථයේ ස්වභාවය බ්රිතාන්ය විද්යාඥ ශ්රීමත් ජේ. ජේ. 1897 දී තොම්සන් [2] සහ 1928 දී අර්වින්ග් ලන්ග්මීර් විසින් "ප්ලාස්මා" ලෙස නම් කරන ලදී. සමහරවිට එය රුධිර ප්ලාස්මා මත ඔහුට මතක් කළ නිසාය. ලන්ග්මියර් මෙසේ ලිවීය:
ඉලෙක්ට්රෝන කිහිපයක් අඩංගු කොපුවල ඇති ඉලෙක්ට්රෝඩයන් ආසන්නයේ හැරුණු විට, අයනීකෘත වායුව නිසා සමාන අයුරින් අයන සහ ඉලෙක්ට්රෝන අඩංගු වන අතර එහි ප්රතිඵලයක් ලෙස අභ්යවකාශ ආරෝපණ ඉතා කුඩා වේ. අයන සහ ඉලෙක්ට්රෝන වල සමබර ආරෝපනයක් සහිත මෙම කලාපය විස්තර කිරීමට නම් ප්ලාස්මා නාමය භාවිතා කළ යුතුය. "[1]
ප්ලාස්මා යනු ස්කන්ධය හා පරිමාව අනුවය. විශ්වයේ බහුලම දෙය වන්නේ සංයුතියයි. [1] තාරකා සියල්ලම ප්ලාස්මා වලින් සෑදූ අතර තාරකා අතර අවකාශය පවා ප්ලාස්මා සමග පිරවිය හැකි නමුත් ඉතා විරල වේ (තාරකාභෞතික ප්ලාස්මා, අන්තර්ගෝලීය මාධ්ය සහ අන්තර්ගෝලීය අවකාශය බලන්න). සූර්ය පද්ධතියේ දී ග්රහ මණ්ඩලයේ නොවන බොහෝ ප්ලූටෝ ග්රහයන්ගෙන් ග්රහයන්ගෙන් සියයට 0.1 ක් හා ප්ලූටෝ කක්ෂය තුල පරිමාව 10-15% ක් පමණ වේ. වායුමය ප්ලාස්මා ඇතුලත ඉතා කුඩා ධාන්ය වර්ගයක් ද සෘණ ආරෝපණ ආරෝපණයක් ලබා ගනී. එසේ කිරීමෙන් ප්ලාස්මා හි ඉතා විශාල සෘණ අයන සංරචකයක් ලෙස ක්රියා කළ හැකි නිසා (ධූලි ප්ලාස්මා බලන්න).
Common forms of plasma include | ||
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ප්ලාස්මා ගුණ හා පැරාමිතිය
![image](https://www.wiki-data.si-lk.nina.az/image/aHR0cHM6Ly93d3cud2lraS1kYXRhLnNpLWxrLm5pbmEuYXovaW1hZ2UvYUhSMGNITTZMeTkxY0d4dllXUXVkMmxyYVcxbFpHbGhMbTl5Wnk5M2FXdHBjR1ZrYVdFdlkyOXRiVzl1Y3k5MGFIVnRZaTlpTDJJNUwxQnNZWE50WVY5bWIzVnVkR0ZwYmk1bmFXWXZNakF3Y0hndFVHeGhjMjFoWDJadmRXNTBZV2x1TG1kcFpnPT0uZ2lm.gif)
අර්ථ දැක්වීම
Although a plasma is loosely described as an electrically neutral medium of positive and negative particles, a definition can have three criteria:
- The plasma approximation: Charged particles must be close enough together that each particle influences many nearby charged particles, rather than just interacting with the closest particle (these collective effects are a distinguishing feature of a plasma). The plasma approximation is valid when the number of charge carriers within the sphere of influence (called the Debye sphere whose radius is the ) of a particular particle are higher than unity to provide collective behavior of the charged particles. The average number of particles in the Debye sphere is given by the , "Λ" (the letter ).
- Bulk interactions: The Debye screening length (defined above) is short compared to the physical size of the plasma. This criterion means that interactions in the bulk of the plasma are more important than those at its edges, where boundary effects may take place. When this criterion is satisfied, the plasma is quasineutral.
- Plasma frequency: The electron plasma frequency (measuring of the electrons) is large compared to the electron-neutral collision frequency (measuring frequency of collisions between electrons and neutral particles). When this condition is valid, electrostatic interactions dominate over the processes of ordinary gas kinetics.
Ranges of plasma parameters
Plasma parameters can take on values varying by many , but the properties of plasmas with apparently disparate parameters may be very similar (see ). The following chart considers only conventional atomic plasmas and not exotic phenomena like :
![image](https://www.wiki-data.si-lk.nina.az/image/aHR0cHM6Ly93d3cud2lraS1kYXRhLnNpLWxrLm5pbmEuYXovaW1hZ2UvYUhSMGNITTZMeTkxY0d4dllXUXVkMmxyYVcxbFpHbGhMbTl5Wnk5M2FXdHBjR1ZrYVdFdlkyOXRiVzl1Y3k5MGFIVnRZaTgwTHpSakwxQnNZWE50WVY5elkyRnNhVzVuTG5OMlp5OHlOVEJ3ZUMxUWJHRnpiV0ZmYzJOaGJHbHVaeTV6ZG1jdWNHNW4ucG5n.png)
Typical ranges of plasma parameters: orders of magnitude (OOM) | ||
Characteristic | Terrestrial plasmas | Cosmic plasmas |
Size in metres | 10−6 m (lab plasmas) to 102 m (lightning) (~8 ) | 10−6 m (spacecraft sheath) to 1025 m (intergalactic nebula) (~31 OOM) |
Lifetime in seconds | 10−12 s (laser-produced plasma) to 107 s (fluorescent lights) (~19 OOM) | 101 s (solar flares) to 1017 s (intergalactic plasma) (~17 OOM) |
Density in particles per cubic metre | 107 m-3 to 1032 m-3 (inertial confinement plasma) | 100 (i.e., 1) m-3 (intergalactic medium) to 1030 m-3 (stellar core) |
Temperature in kelvins | ~0 K (crystalline non-neutral plasma) to 108 K (magnetic fusion plasma) | 102 K (aurora) to 107 K (solar core) |
Magnetic fields in teslas | 10−4 T (lab plasma) to 103 T (pulsed-power plasma) | 10−12 T (intergalactic medium) to 1011 T (near neutron stars) |
Degree of ionization
For plasma to exist, is necessary. The term "plasma density" by itself usually refers to the "electron density", that is, the number of free electrons per unit volume. The of a plasma is the proportion of atoms which have lost (or gained) electrons, and is controlled mostly by the temperature. Even a partially ionized gas in which as little as 1% of the particles are ionized can have the characteristics of a plasma (i.e. respond to magnetic fields and be highly electrically conductive). The degree of ionization, α is defined as α = ni/(ni + na) where ni is the number density of ions and na is the number density of neutral atoms. The electron density is related to this by the average charge state <Z> of the ions through ne=<Z> ni where ne is the number density of electrons.
උෂ්ණත්වය
ප්ලාස්මා උෂ්ණත්වය සාමාන්යයෙන් මනිනු ලබන්නේ [[[]] හෝ වල වන අතර එය අංශුවකට තාප චාලක ශක්තියේ අවිධිමත් මිනුමකි. ශක්තියෙන් [[බෙදා හැරීමේ කාර්යය] සැලකිය යුතු ලෙස අපගමනය වූ විට පවා ඉලෙක්ට්රෝන ආසන්නව පිහිටා ඇත. ]], උදාහරණයක් ලෙස පාරජම්බුල කිරණ, ශක්තිජනක අංශු හෝ ශක්තිමත් හේතුවෙන්. ස්කන්ධයේ විශාල වෙනස නිසා ඉලෙක්ට්රෝන අයන හෝ උදාසීන පරමාණු සමඟ සමතුලිතතාවයට පැමිණීමට වඩා වේගයෙන් තාප ගතික සමතුලිතතාවයට පැමිණේ. මේ හේතුව නිසා "අයන උෂ්ණත්වය" " ට වඩා බෙහෙවින් වෙනස් විය හැකිය. දුර්වල අයනීකෘත තාක්ෂණික ප්ලාස්මා වල මෙය විශේෂයෙන් සුලභ වේ, අයන බොහෝ විට අසල ඇත.
ඉලෙක්ට්රෝන, අයන සහ උදාසීන වල සාපේක්ෂ උෂ්ණත්වය මත පදනම්ව, ප්ලාස්මා "තාප" හෝ "තාප නොවන" ලෙස වර්ගීකරණය කර ඇත. තාප ප්ලාස්මා වල ඉලෙක්ට්රෝන හා බර අංශු එකම උෂ්ණත්වයේ පවතී, එනම් ඒවා එකිනෙකා සමඟ තාප සමතුලිතතාවයේ පවතී. අනෙක් අතට තාප නොවන ප්ලාස්මා වලට අයන හා උදාසීන වඩා අඩු උෂ්ණත්වයක (සාමාන්යයෙන් කාමර උෂ්ණත්වය) ඇති අතර ඉලෙක්ට්රෝන බොහෝ “උණුසුම්” වේ.
උෂ්ණත්වය ප්ලාස්මා අයනීකරණයේ මට්ටම පාලනය කරයි. විශේෂයෙන්, නමින් හැඳින්වෙන සම්බන්ධතාවයක අයනීකරණ ශක්තිය (හා වඩා දුර්වල ලෙස ity නත්වය අනුව) සාපේක්ෂව “ඉලෙක්ට්රෝන උෂ්ණත්වය” මගින් ප්ලාස්මා අයනීකරණය තීරණය වේ. ප්ලාස්මා සමහර විට සම්පූර්ණයෙන්ම අයනීකරණය වී ඇත්නම් එය "උණුසුම්" හෝ වායු අණු වලින් කුඩා කොටසක් (උදාහරණයක් ලෙස 1%) අයනීකරණය වී ඇත්නම් "සීතල" ලෙස හැඳින්වේ (නමුත් "උණුසුම් ප්ලාස්මා" යන යෙදුම්වල වෙනත් අර්ථ දැක්වීම් සහ "සීතල ප්ලාස්මා" පොදු වේ). “සීතල” ප්ලාස්මා වල වුවද ඉලෙක්ට්රෝන උෂ්ණත්වය තවමත් සෙල්සියස් අංශක දහස් ගණනකි. "ප්ලාස්මා තාක්ෂණය" ("තාක්ෂණික ප්ලාස්මා") සඳහා භාවිතා කරන ප්ලාස්මා සාමාන්යයෙන් මෙම අර්ථයෙන් සීතල වේ.
Potentials
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Since plasmas are very good conductors, electric potentials play an important role. The potential as it exists on average in the space between charged particles, independent of the question of how it can be measured, is called the "plasma potential" or the "space potential". If an electrode is inserted into a plasma, its potential will generally lie considerably below the plasma potential due to what is termed a . The good electrical conductivity of plasmas causes their electric fields to be very small. This results in the important concept of "quasineutrality", which says the density of negative charges is approximately equal to the density of positive charges over large volumes of the plasma (), but on the scale of the Debye length there can be charge imbalance. In the special case that are formed, the charge separation can extend some tens of Debye lengths.
The magnitude of the potentials and electric fields must be determined by means other than simply finding the net . A common example is to assume that the electrons satisfy the "":
.
Differentiating this relation provides a means to calculate the electric field from the density:
.
It is possible to produce a plasma which is not quasineutral. An electron beam, for example, has only negative charges. The density of a non-neutral plasma must generally be very low, or it must be very small, otherwise it will be dissipated by the repulsive .
In plasmas, prevents from directly affecting the plasma over large distances (ie. greater than the ). But the existence of charged particles causes the plasma to generate and be affected by . This can and does cause extremely complex behavior, such as the generation of plasma double layers, an object which separates charge over a few tens of . The dynamics of plasmas interacting with external and self-generated are studied in the of .
චුම්භකනය
A plasma in which the magnetic field is strong enough to influence the motion of the charged particles is said to be magnetized. A common quantitative criterion is that a particle on average completes at least one gyration around the magnetic field before making a collision (ie. where
is the "electron gyrofrequency" and
is the "electron collision rate"). It is often the case that the electrons are magnetized while the ions are not. Magnetized plasmas are , meaning that their properties in the direction parallel to the magnetic field are different from those perpendicular to it. While electric fields in plasmas are usually small due to the high conductivity, the electric field associated with a plasma moving in a magnetic field is given by E = -v x B (where E is the electric field, v is the velocity, and B is the magnetic field), and is not affected by .
Comparison of plasma and gas phases
Plasma is often called the fourth state of matter. It is distinct from other lower-energy ; most commonly , liquid, and gas, although it is closely related to the gas phase in that it also has no definite form or volume. Physicists consider a plasma to be more than a gas[] because of a number of distinct properties including the following:
Property | Gas | Plasma |
Very low
| Usually very high
| |
Independently acting species | One
| Two or three
|
Velocity distribution |
| Often non-Maxwellian
|
Interactions | Binary
| Collective
|
Complex plasma phenomena
Although the underlying equations governing plasmas are relatively simple, plasma behaviour is extraordinarily varied and subtle: the emergence of unexpected behaviour from a simple model is a typical feature of a . Such systems lie in some sense on the boundary between ordered and disordered behaviour, and cannot typically be described either by simple, smooth, mathematical functions, or by pure randomness. The spontaneous formation of interesting spatial features on a wide range of length scales is one manifestation of plasma complexity. The features are interesting, for example, because they are very sharp, spatially intermittent (the distance between features is much larger than the features themselves), or have a form. Many of these features were first studied in the laboratory, and have subsequently been recognised throughout the universe. Examples of complexity and complex structures in plasmas include:
Filamentation
Striations or string-like structures are seen in many plasmas, like the plasma ball (image above), the ,,, , and . They are sometimes associated with larger current densities, and the interaction with the magnetic field can form a magnetic rope structure. (See also )
Shocks or double layers
Plasma properties change rapidly (within a few Debye lengths) across a two-dimensional sheet in the presence of a (moving) shock or (stationary) . Double layers involve localised charge separation, which causes a large potential difference across the layer, but does not generate an electric field outside the layer. Double layers separate adjacent plasma regions with different physical characteristics, and are often found in current carrying plasmas. They accelerate both ions and electrons.
Electric fields and circuits
Quasineutrality of a plasma requires that plasma currents close on themselves in electric circuits. Such circuits follow , and possess a and . These circuits must generally be treated as a strongly coupled system, with the behaviour in each plasma region dependent on the entire circuit. It is this strong coupling between system elements, together with nonlinearity, which may lead to complex behaviour. Electrical circuits in plasmas store inductive (magnetic) energy, and should the circuit be disrupted, for example, by a plasma instability, the inductive energy will be released as plasma heating and acceleration. This is a common explanation for the heating which takes place in the . Electric currents, and in particular, magnetic-field-aligned electric currents (which are sometimes generically referred to as ""), are also observed in the Earth's aurora, and in plasma filaments.
Cellular structure
Narrow sheets with sharp gradients may separate regions with different properties such as magnetization, density, and temperature, resulting in cell-like regions. Examples include the , , and . Hannes Alfvén wrote: "From the cosmological point of view, the most important new space research discovery is probably the cellular structure of space. As has been seen, in every region of space which is accessible to in situ measurements, there are a number of 'cell walls', sheets of electric currents, which divide space into compartments with different magnetization, temperature, density, etc ."
Critical ionization velocity
The is the relative velocity between an (magnetized) ionized plasma and a neutral gas above which a runaway ionization process takes place. The critical ionization process is a quite general mechanism for the conversion of the kinetic energy of a rapidly streaming gas into ionization and plasma thermal energy. Critical phenomena in general are typical of complex systems, and may lead to sharp spatial or temporal features.
Ultracold plasma
It is possible to create ultracold plasmas, by using lasers to trap and cool neutral atoms to temperatures of 1 or lower. Another laser then ionizes the atoms by giving each of the outermost electrons just enough energy to escape the electrical attraction of its parent ion.
The key point about ultracold plasmas is that by manipulating the atoms with lasers, the kinetic energy of the liberated electrons can be controlled. Using standard pulsed lasers, the electron energy can be made to correspond to a temperature of as low as 0.1 K, a limit set by the frequency bandwidth of the laser pulse. The ions, however, retain the millikelvin temperatures of the neutral atoms. This type of non-equilibrium ultracold plasma evolves rapidly, and many fundamental questions about its behaviour remain unanswered. Experiments conducted so far have revealed surprising dynamics and recombination behavior which are pushing the limits of our knowledge of plasma physics.[] One of the metastable states of strongly nonideal plasma is which forms upon condensation of excited atoms.
ආරෝපිත ප්ලැස්මා
The strength and range of the electric force and the good conductivity of plasmas usually ensure that the density of positive and negative charges in any sizeable region are equal ("quasineutrality"). A plasma which has a significant excess of charge density or which is, in the extreme case, composed of only a single species, is called a non-neutral plasma. In such a plasma, electric fields play a dominant role. Examples are charged , an electron cloud in a , and positron plasmas.
Dusty plasma and grain plasma
A is one containing tiny charged particles of dust (typically found in space) which also behaves like a plasma. A plasma containing larger particles is called a grain plasma.
Mathematical descriptions
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To completely describe the state of a plasma, we would need to write down all the particle locations and velocities, and describe the electromagnetic field in the plasma region. However, it is generally not practical or necessary to keep track of all the particles in a plasma. Therefore, plasma physicists commonly use less detailed descriptions known as models, of which there are two main types:
ද්රව ආකාතිය
Fluid models describe plasmas in terms of smoothed quantities like density and averaged velocity around each position (see ). One simple fluid model, , treats the plasma as a single fluid governed by a combination of and the . A more general description is the two-fluid picture, where the ions and electrons are described separately. Fluid models are often accurate when collisionality is sufficiently high to keep the plasma velocity distribution close to a . Because fluid models usually describe the plasma in terms of a single flow at a certain temperature at each spatial location, they can neither capture velocity space structures like beams or nor resolve wave-particle effects.
ගතික ප්ලැස්මා
Kinetic models describe the particle velocity distribution function at each point in the plasma, and therefore do not need to assume a . A kinetic description is often necessary for collisionless plasmas. There are two common approaches to kinetic description of a plasma. One is based on representing the smoothed distribution function on a grid in velocity and position. The other, known as the (PIC) technique, includes kinetic information by following the trajectories of a large number of individual particles. Kinetic models are generally more computationally intensive than fluid models. The may be used to describe the dynamics of a system of charged particles interacting with an electromagnetic field.
කෘතිම ප්ලැස්මා
Most artificial plasmas are generated by the application of electric and/or magnetic fields. Plasma generated in a laboratory setting and for industrial use can be generally categorized by:
- The type of power source used to generate the plasma; DC, RF and microwave.
- The pressure at which they operate; vacuum pressure (< 10 mTorr), moderate pressure (~ 1 Torr), and atmospheric pressure (760 Torr).
- The degree of ionization within the plasma; fully ionized, partially ionized, weakly ionized.
- The temperature relationships within the plasma; Thermal plasma (Te = Tion = Tgas), Non-Thermal or "cold" plasma (Te >> Tion = Tgas)
- The electrode configuration used to generate the plasma.
- The magnetization of the particles within the plasma; Magnetized (both ion and electrons are trapped in by the magnetic field), partially magnetized (the electrons but not the ions are trapped by the magnetic field), non-magnetized (the magnetic field is too weak to trap the particles in orbits but may generate Lorentz forces).
- Its application
Examples of industrial/commercial plasma
Low-pressure discharges
- plasmas: non-thermal plasmas generated by the application of DC or low frequency RF (<100 kHz) electric field to the gap between two metal electrodes. Probably the most common plasma; this is the type of plasma generated within tubes.
- (CCP): similar to glow discharge plasmas, but generated with high frequency RF electric fields, typically 13.56 MHz. These differ from glow discharges in that the sheaths are much less intense. These are widely used in the microfabrication and integrated circuit manufacturing industries for plasma etching and plasma enhanced chemical vapor deposition.
- (ICP): similar to a CCP and with similar applications but the electrode consists of a coil wrapped around the discharge volume which inductively excites the plasma.
- : similar to CCP and ICP in that it is typically RF (or microwave), but is heated by both electrostatic and electromagnetic means. Examples are , (ECR), and (ICR). These typically require a coaxial magnetic field for wave propagation.
Atmospheric pressure
- : this is a high power thermal discharge of very high temperature ~10,000 K. It can be generated using various power supplies. It is commonly used in processes. For example it is used to melt rocks containing Al2O3 to produce aluminium.
- : this is a non-thermal discharge generated by the application of high voltage to sharp electrode tips. It is commonly used in generators and particle precipitators.
- (DBD): this is a non-thermal discharge generated by the application of high voltages across small gaps wherein a non-conducting coating prevents the transition of the plasma discharge into an arc. It is often mislabeled 'Corona' discharge in industry and has similar application to corona discharges. It is also widely used in the web treatment of fabrics. The application of the discharge to synthetic fabrics and plastics functionalizes the surface and allows for paints, glues and similar materials to adhere.
Fields of active research
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This is just a partial list of topics. A more complete and organized list can be found on the Web site for Plasma science and technology.
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මේවාත් බලන්න
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සටහන්
- IPPEX Glossary of Fusion Terms, http://ippex.pppl.gov/fusion/glossary.html, ප්රතිෂ්ඨාපනය 2008-08-23
- Plasma fountain Source, press release: Solar Wind Squeezes Some of Earth's Atmosphere into Space
- R. O. Dendy, Plasma Dynamics.
- Hillary Walter, Michelle Cooper, Illustrated Dictionary of Physics
- Daniel Hastings, Henry Garrett, Spacecraft-Environment Interactions
- After Peratt, A. L., "Advances in Numerical Modeling of Astrophysical and Space Plasmas" (1966) Astrophysics and Space Science, v. 242, Issue 1/2, p. 93-163.
- See The Nonneutral Plasma Group 2017-07-18 at the Wayback Machine at the University of California, San Diego
- See Flashes in the Sky: Earth's Gamma-Ray Bursts Triggered by Lightning
- Richard Fitzpatrick, Introduction to Plasma Physics, Magnetized plasmas
- Hong, Alice (2000). "Dielectric Strength of Air". The Physics Factbook.
- Dickel, J. R., "The Filaments in Supernova Remnants: Sheets, Strings, Ribbons, or?" (1990) Bulletin of the American Astronomical Society, Vol. 22, p.832
- Grydeland, T., et al, "Interferometric observations of filamentary structures associated with plasma instability in the auroral ionosphere" (2003) Geophysical Research Letters, Volume 30, Issue 6, pp. 71-1
- Moss, Gregory D., et al, "Monte Carlo model for analysis of thermal runaway electrons in streamer tips in transient luminous events and streamer zones of lightning leaders" (2006) Journal of Geophysical Research, Volume 111, Issue A2, CiteID A02307
- Doherty, Lowell R., "Filamentary Structure in Solar Prominences." (1965) Astrophysical Journal, vol. 141, p.251
- Hubble views the Crab Nebula M1: The Crab Nebula Filaments, http://seds.lpl.arizona.edu/messier/more/m001_hst.html, ප්රතිෂ්ඨාපනය 2009-10-05
- Zhang, Yan-An, et al, "A rope-shaped solar filament and a IIIb flare" (2002) Chinese Astronomy and Astrophysics, Volume 26, Issue 4, p. 442-450
- Hannes Alfvén, Cosmic Plasma (1981) See section VI.13.1. Cellular Structure of Space.
- R. G. Greaves, M. D. Tinkle, and C. M. Surko, "Creation and uses of positron plasmas", Physics of Plasmas -- May 1994 -- Volume 1, Issue 5, pp. 1439-1446
- See Evolution of the Solar System, 1976)
- Web site for Plasma science and technology 2015-05-09 at the Wayback Machine
බාහිරට යොමු
- Plasmas: the Fourth State of Matter
- Animation on the plasma excitation 2009-01-30 at the Wayback Machine
- Plasma Science and Technology
- Plasma on the Internet comprehensive list of plasma related links.
- Introduction to Plasma Physics: Graduate course given by Richard Fitzpatrick 2010-01-04 at the Wayback Machine | M.I.T. Introduction by I.H.Hutchinson
- NRL Plasma Formulary online 2007-04-28 at the Wayback Machine (or an html version 2007-02-08 at the Wayback Machine)
- Plasma Coalition page
- Plasma Material Interaction 2005-03-08 at the Wayback Machine
- How to make a glowing ball of plasma in your microwave with a grape 2005-09-06 at the Wayback Machine | More (Video)
- How to make plasma in your microwave with only one match (video)
- Plasma Ignition How to make a plasma ignition system (Video)
- U.S. Dept of Agriculture research project "Decontamination of Fresh Produce with Cold Plasma"
- CNRS LAEPT "Electric Arc Thermal Plasmas 2012-01-27 at the Wayback Machine (french)
විකිපීඩියාව, විකි, සිංහල, පොත, පොත්, පුස්තකාලය, ලිපිය, කියවන්න, බාගන්න, නොමිලේ, නොමිලේ බාගන්න, mp3, වීඩියෝ, mp4, 3gp, jpg, jpeg, gif, png, පින්තූරය, සංගීතය, ගීතය, චිත්රපටය, පොත, ක්රීඩාව, ක්රීඩා., ජංගම දුරකථන, android, ios, apple, ජංගම දුරකථන, samsung, iphone, xiomi, xiaomi, redmi, honor, oppo, nokia, sonya, mi, පීසී, වෙබ්, පරිගණකය
ම ම ල ප ය ව ඩ ද ය ණ කළය ත ව ඇත ව නත භ ෂ ව ක ල ප යක පදනම ව පර වර තනය ක ර ම න හ ඔබ ම ම ම ත ක ව ප ල බඳව ද න වත නම අල ත කර ණ එක ක ර ම න සහ ස ශ ධනය න හ ද යකවන න භ ත ක ව ද ය ව හ සහ රස යන ව ද ය ව හ ප ල ස ම යන ව ය වක අ ශ ක ස යම ප රම ණයක අයන ක ත ව ව ට න ම ව න පද ර ථය අවස ථ වක illustrating some of the more complex phenomena of a plasma including The colors are a result of relaxation of electrons in excited states to lower energy states after they have recombined with ions These processes emit light in a characteristic of the gas being excited ප ල ස ම අවස ථ ව ද අයන ක ත ව ය වක වන අතර ඉල ක ට ර නයක යම අන ප තයක න දහස වන අතර ඒව පරම ණ වකට හ අණ වක ව තට බ ඳ ඇත ධන ත මක හ ස ණ ආර පණ තරමක ස ව ධ නව ගමන ක ර මට හ ක ය ව ඇත ව ද ය ත ච ම බක ක ෂ ත රයට ද ඩ ල ස ප රත ච ර ද ක ව මට ප ල ස ම ව ද ල ය සන න යක ව එබ ව න ප ල ස ම ඝන ද රව ය ද රව හ ව ය න ම න න ව එහ ද රව යමය තත වයක ල ස ස ලක ප ල ස ම ස ම න යය න උද ස න ව ය වළ ක ළ ආක රයක උද තර උද ව ඉත හ සයම ම පද ර ථය පළම වරට ක ක ස නලයක ත ළ ම ල න ම හද න ගත අතර 1879 ද ශ ර මත ව ල යම ක ර ක ස ව ස න ව ස තර කරන ලද ඔහ එය ව ක රණමය පද ර ථයය ල ස හ ඳ න ව 1 ක ර ක ස න ලය ක ත ඩ ක රණ යන පද ර ථය ස වභ වය බ ර ත න ය ව ද ය ඥ ශ ර මත ජ ජ 1897 ද ත ම සන 2 සහ 1928 ද අර ව න ග ලන ග ම ර ව ස න ප ල ස ම ල ස නම කරන ලද සමහරව ට එය ර ධ ර ප ල ස ම මත ඔහ ට මතක කළ න ස ය ලන ග ම යර ම ස ල ව ය ඉල ක ට ර න ක හ පයක අඩ ග ක ප වල ඇත ඉල ක ට ර ඩයන ආසන නය හ ර ණ ව ට අයන ක ත ව ය ව න ස සම න අය ර න අයන සහ ඉල ක ට ර න අඩ ග වන අතර එහ ප රත ඵලයක ල ස අභ යවක ශ ආර පණ ඉත ක ඩ ව අයන සහ ඉල ක ට ර න වල සමබර ආර පනයක සහ ත ම ම කල පය ව ස තර ක ර මට නම ප ල ස ම න මය භ ව ත කළ ය ත ය 1 ප ල ස ම යන ස කන ධය හ පර ම ව අන වය ව ශ වය බහ ලම ද ය වන න ස ය ත යය 1 ත රක ස යල ලම ප ල ස ම වල න ස ද අතර ත රක අතර අවක ශය පව ප ල ස ම සමග ප රව ය හ ක නම ත ඉත ව රල ව ත රක භ ත ක ප ල ස ම අන තර ග ල ය ම ධ ය සහ අන තර ග ල ය අවක ශය බලන න ස ර ය පද ධත ය ද ග රහ මණ ඩලය න වන බ හ ප ල ට ග රහයන ග න ග රහයන ග න ස යයට 0 1 ක හ ප ල ට කක ෂය ත ල පර ම ව 10 15 ක පමණ ව ව ය මය ප ල ස ම ඇත ලත ඉත ක ඩ ධ න ය වර ගයක ද ස ණ ආර පණ ආර පණයක ලබ ගන එස ක ර ම න ප ල ස ම හ ඉත ව ශ ල ස ණ අයන ස රචකයක ල ස ක ර ය කළ හ ක න ස ධ ල ප ල ස ම බලන න Common forms of plasma includeක ත මව න පදව ප ල ස ම Those found in including TVs Inside low energy lighting Rocket exhaust The area in front of a spacecraft s during reentry into the atmosphere Inside a corona discharge generator research The in an an arc or Plasma ball sometimes called a plasma sphere or Arcs produced by resonant air core transformer or disruptor coil that produces arcs similar to lightning but with rather than Plasmas used in including andTerrestrial plasmas අක ණ Theand astrophysical plasmas The හ ර ඇත ළ ස යළ තර s which are plasmas heated by nuclear fusion The the space between the planets The the space between star systems The the space between galaxies The Io Jupiter flux tube Interstellarප ල ස ම ග ණ හ ප ර ම ත යThe Earth s showing oxygen helium and hydrogen ions which gush into space from regions near the Earth s poles The faint yellow area shown above the north pole represents gas lost from Earth into space the green area is the or plasma energy pouring back into the atmosphere අර ථ ද ක ව ම Although a plasma is loosely described as an electrically neutral medium of positive and negative particles a definition can have three criteria The plasma approximation Charged particles must be close enough together that each particle influences many nearby charged particles rather than just interacting with the closest particle these collective effects are a distinguishing feature of a plasma The plasma approximation is valid when the number of charge carriers within the sphere of influence called the Debye sphere whose radius is the of a particular particle are higher than unity to provide collective behavior of the charged particles The average number of particles in the Debye sphere is given by the L the letter Bulk interactions The Debye screening length defined above is short compared to the physical size of the plasma This criterion means that interactions in the bulk of the plasma are more important than those at its edges where boundary effects may take place When this criterion is satisfied the plasma is quasineutral Plasma frequency The electron plasma frequency measuring of the electrons is large compared to the electron neutral collision frequency measuring frequency of collisions between electrons and neutral particles When this condition is valid electrostatic interactions dominate over the processes of ordinary gas kinetics Ranges of plasma parameters Plasma parameters can take on values varying by many but the properties of plasmas with apparently disparate parameters may be very similar see The following chart considers only conventional atomic plasmas and not exotic phenomena like Range of plasmas Density increases upwards temperature increases towards the right The free electrons in a metal may be considered an electron plasmaTypical ranges of plasma parameters orders of magnitude OOM CharacteristicTerrestrial plasmasCosmic plasmasSize in metres10 6 m lab plasmas to 102 m lightning 8 10 6 m spacecraft sheath to 1025 m intergalactic nebula 31 OOM Lifetime in seconds10 12 s laser produced plasma to 107 s fluorescent lights 19 OOM 101 s solar flares to 1017 s intergalactic plasma 17 OOM Density in particles per cubic metre107 m 3 to 1032 m 3 inertial confinement plasma 100 i e 1 m 3 intergalactic medium to 1030 m 3 stellar core Temperature in kelvins 0 K crystalline non neutral plasma to 108 K magnetic fusion plasma 102 K aurora to 107 K solar core Magnetic fields in teslas10 4 T lab plasma to 103 T pulsed power plasma 10 12 T intergalactic medium to 1011 T near neutron stars Degree of ionization For plasma to exist is necessary The term plasma density by itself usually refers to the electron density that is the number of free electrons per unit volume The of a plasma is the proportion of atoms which have lost or gained electrons and is controlled mostly by the temperature Even a partially ionized gas in which as little as 1 of the particles are ionized can have the characteristics of a plasma i e respond to magnetic fields and be highly electrically conductive The degree of ionization a is defined as a ni ni na where ni is the number density of ions and na is the number density of neutral atoms The electron density is related to this by the average charge state lt Z gt of the ions through ne lt Z gt ni where ne is the number density of electrons උෂ ණත වය ප ල ස ම උෂ ණත වය ස ම න යය න මන න ලබන න හ වල වන අතර එය අ ශ වකට ත ප ච ලක ශක ත ය අව ධ මත ම න මක ශක ත ය න බ ද හ ර ම ක ර යය ස ලක ය ය ත ල ස අපගමනය ව ව ට පව ඉල ක ට ර න ආසන නව ප හ ට ඇත උද හරණයක ල ස ප රජම බ ල ක රණ ශක ත ජනක අ ශ හ ශක ත මත හ ත ව න ස කන ධය ව ශ ල ව නස න ස ඉල ක ට ර න අයන හ උද ස න පරම ණ සමඟ සමත ල තත වයට ප ම ණ මට වඩ ව ගය න ත ප ගත ක සමත ල තත වයට ප ම ණ ම හ ත ව න ස අයන උෂ ණත වය ට වඩ බ හ ව න ව නස ව ය හ ක ය ද ර වල අයන ක ත ත ක ෂණ ක ප ල ස ම වල ම ය ව ශ ෂය න ස ලභ ව අයන බ හ ව ට අසල ඇත ඉල ක ට ර න අයන සහ උද ස න වල ස ප ක ෂ උෂ ණත වය මත පදනම ව ප ල ස ම ත ප හ ත ප න වන ල ස වර ග කරණය කර ඇත ත ප ප ල ස ම වල ඉල ක ට ර න හ බර අ ශ එකම උෂ ණත වය පවත එනම ඒව එක න ක සමඟ ත ප සමත ල තත වය පවත අන ක අතට ත ප න වන ප ල ස ම වලට අයන හ උද ස න වඩ අඩ උෂ ණත වයක ස ම න යය න ක මර උෂ ණත වය ඇත අතර ඉල ක ට ර න බ හ උණ ස ම ව උෂ ණත වය ප ල ස ම අයන කරණය මට ටම ප ලනය කරය ව ශ ෂය න නම න හ ඳ න ව න සම බන ධත වයක අයන කරණ ශක ත ය හ වඩ ද ර වල ල ස ity නත වය අන ව ස ප ක ෂව ඉල ක ට ර න උෂ ණත වය මග න ප ල ස ම අයන කරණය ත රණය ව ප ල ස ම සමහර ව ට සම ප ර ණය න ම අයන කරණය ව ඇත නම එය උණ ස ම හ ව ය අණ වල න ක ඩ ක ටසක උද හරණයක ල ස 1 අයන කරණය ව ඇත නම ස තල ල ස හ ඳ න ව නම ත උණ ස ම ප ල ස ම යන ය ද ම වල ව නත අර ථ ද ක ව ම සහ ස තල ප ල ස ම ප ද ව ස තල ප ල ස ම වල ව වද ඉල ක ට ර න උෂ ණත වය තවමත ස ල ස යස අ ශක දහස ගණනක ප ල ස ම ත ක ෂණය ත ක ෂණ ක ප ල ස ම සඳහ භ ව ත කරන ප ල ස ම ස ම න යය න ම ම අර ථය න ස තල ව Potentials is an example of plasma present at Earth s surface Typically lightning discharges 30 000 amperes at up to 100 million volts and emits light radio waves x rays and even gamma rays Plasma temperatures in lightning can approach 28 000 Kelvin 27 700 C and electron densities may exceed 1024 m Since plasmas are very good conductors electric potentials play an important role The potential as it exists on average in the space between charged particles independent of the question of how it can be measured is called the plasma potential or the space potential If an electrode is inserted into a plasma its potential will generally lie considerably below the plasma potential due to what is termed a The good electrical conductivity of plasmas causes their electric fields to be very small This results in the important concept of quasineutrality which says the density of negative charges is approximately equal to the density of positive charges over large volumes of the plasma ne Z ni displaystyle n e langle Z rangle n i but on the scale of the Debye length there can be charge imbalance In the special case that are formed the charge separation can extend some tens of Debye lengths The magnitude of the potentials and electric fields must be determined by means other than simply finding the net A common example is to assume that the electrons satisfy the ne eeF kBTe displaystyle n e propto e e Phi k B T e Differentiating this relation provides a means to calculate the electric field from the density E kBTe e ne ne displaystyle vec E k B T e e nabla n e n e It is possible to produce a plasma which is not quasineutral An electron beam for example has only negative charges The density of a non neutral plasma must generally be very low or it must be very small otherwise it will be dissipated by the repulsive In plasmas prevents from directly affecting the plasma over large distances ie greater than the But the existence of charged particles causes the plasma to generate and be affected by This can and does cause extremely complex behavior such as the generation of plasma double layers an object which separates charge over a few tens of The dynamics of plasmas interacting with external and self generated are studied in the of ච ම භකනය A plasma in which the magnetic field is strong enough to influence the motion of the charged particles is said to be magnetized A common quantitative criterion is that a particle on average completes at least one gyration around the magnetic field before making a collision ie wce ncoll gt 1 displaystyle omega ce nu coll gt 1 where wce displaystyle omega ce is the electron gyrofrequency and ncoll displaystyle nu coll is the electron collision rate It is often the case that the electrons are magnetized while the ions are not Magnetized plasmas are meaning that their properties in the direction parallel to the magnetic field are different from those perpendicular to it While electric fields in plasmas are usually small due to the high conductivity the electric field associated with a plasma moving in a magnetic field is given by E v x B where E is the electric field v is the velocity and B is the magnetic field and is not affected by Comparison of plasma and gas phases Plasma is often called the fourth state of matter It is distinct from other lower energy most commonly liquid and gas although it is closely related to the gas phase in that it also has no definite form or volume Physicists consider a plasma to be more than a gas තහව ර කර න ම ත because of a number of distinct properties including the following Property Gas PlasmaVery low Air is an excellent insulator until it breaks down into plasma at electric field strengths above 30 kilovolts per centimeter Usually very high For many purposes the of a plasma may be treated as infinite Independently acting species One All gas particles behave in a similar way influenced by gravity and with one another Two or three and neutrals can be distinguished by the sign of their so that they behave independently in many circumstances with different bulk velocities and temperatures allowing phenomena such as new types of andVelocity distribution Collisions usually lead to a Maxwellian velocity distribution of all gas particles with very few relatively fast particles Often non Maxwellian Collisional interactions are often weak in hot plasmas and external forcing can drive the plasma far from local equilibrium and lead to a significant population of unusually fast particles Interactions Binary Two particle collisions are the rule three body collisions extremely rare Collective Waves or organised motion of plasma are very important because the particles can interact at long ranges through the electric and magnetic forces Complex plasma phenomenaAlthough the underlying equations governing plasmas are relatively simple plasma behaviour is extraordinarily varied and subtle the emergence of unexpected behaviour from a simple model is a typical feature of a Such systems lie in some sense on the boundary between ordered and disordered behaviour and cannot typically be described either by simple smooth mathematical functions or by pure randomness The spontaneous formation of interesting spatial features on a wide range of length scales is one manifestation of plasma complexity The features are interesting for example because they are very sharp spatially intermittent the distance between features is much larger than the features themselves or have a form Many of these features were first studied in the laboratory and have subsequently been recognised throughout the universe Examples of complexity and complex structures in plasmas include Filamentation Striations or string like structures are seen in many plasmas like the plasma ball image above the and They are sometimes associated with larger current densities and the interaction with the magnetic field can form a magnetic rope structure See also Shocks or double layers Plasma properties change rapidly within a few Debye lengths across a two dimensional sheet in the presence of a moving shock or stationary Double layers involve localised charge separation which causes a large potential difference across the layer but does not generate an electric field outside the layer Double layers separate adjacent plasma regions with different physical characteristics and are often found in current carrying plasmas They accelerate both ions and electrons Electric fields and circuits Quasineutrality of a plasma requires that plasma currents close on themselves in electric circuits Such circuits follow and possess a and These circuits must generally be treated as a strongly coupled system with the behaviour in each plasma region dependent on the entire circuit It is this strong coupling between system elements together with nonlinearity which may lead to complex behaviour Electrical circuits in plasmas store inductive magnetic energy and should the circuit be disrupted for example by a plasma instability the inductive energy will be released as plasma heating and acceleration This is a common explanation for the heating which takes place in the Electric currents and in particular magnetic field aligned electric currents which are sometimes generically referred to as are also observed in the Earth s aurora and in plasma filaments Cellular structure Narrow sheets with sharp gradients may separate regions with different properties such as magnetization density and temperature resulting in cell like regions Examples include the and Hannes Alfven wrote From the cosmological point of view the most important new space research discovery is probably the cellular structure of space As has been seen in every region of space which is accessible to in situ measurements there are a number of cell walls sheets of electric currents which divide space into compartments with different magnetization temperature density etc Critical ionization velocity The is the relative velocity between an magnetized ionized plasma and a neutral gas above which a runaway ionization process takes place The critical ionization process is a quite general mechanism for the conversion of the kinetic energy of a rapidly streaming gas into ionization and plasma thermal energy Critical phenomena in general are typical of complex systems and may lead to sharp spatial or temporal features Ultracold plasma It is possible to create ultracold plasmas by using lasers to trap and cool neutral atoms to temperatures of 1 or lower Another laser then ionizes the atoms by giving each of the outermost electrons just enough energy to escape the electrical attraction of its parent ion The key point about ultracold plasmas is that by manipulating the atoms with lasers the kinetic energy of the liberated electrons can be controlled Using standard pulsed lasers the electron energy can be made to correspond to a temperature of as low as 0 1 K a limit set by the frequency bandwidth of the laser pulse The ions however retain the millikelvin temperatures of the neutral atoms This type of non equilibrium ultracold plasma evolves rapidly and many fundamental questions about its behaviour remain unanswered Experiments conducted so far have revealed surprising dynamics and recombination behavior which are pushing the limits of our knowledge of plasma physics තහව ර කර න ම ත One of the metastable states of strongly nonideal plasma is which forms upon condensation of excited atoms ආර ප ත ප ල ස ම The strength and range of the electric force and the good conductivity of plasmas usually ensure that the density of positive and negative charges in any sizeable region are equal quasineutrality A plasma which has a significant excess of charge density or which is in the extreme case composed of only a single species is called a non neutral plasma In such a plasma electric fields play a dominant role Examples are charged an electron cloud in a and positron plasmas Dusty plasma and grain plasma A is one containing tiny charged particles of dust typically found in space which also behaves like a plasma A plasma containing larger particles is called a grain plasma Mathematical descriptionsThe complex self constricting magnetic field lines and current paths in a field aligned which may develop in a plasmaම ල ක ල ප ය To completely describe the state of a plasma we would need to write down all the particle locations and velocities and describe the electromagnetic field in the plasma region However it is generally not practical or necessary to keep track of all the particles in a plasma Therefore plasma physicists commonly use less detailed descriptions known as models of which there are two main types ද රව ආක ත ය Fluid models describe plasmas in terms of smoothed quantities like density and averaged velocity around each position see One simple fluid model treats the plasma as a single fluid governed by a combination of and the A more general description is the two fluid picture where the ions and electrons are described separately Fluid models are often accurate when collisionality is sufficiently high to keep the plasma velocity distribution close to a Because fluid models usually describe the plasma in terms of a single flow at a certain temperature at each spatial location they can neither capture velocity space structures like beams or nor resolve wave particle effects ගත ක ප ල ස ම Kinetic models describe the particle velocity distribution function at each point in the plasma and therefore do not need to assume a A kinetic description is often necessary for collisionless plasmas There are two common approaches to kinetic description of a plasma One is based on representing the smoothed distribution function on a grid in velocity and position The other known as the PIC technique includes kinetic information by following the trajectories of a large number of individual particles Kinetic models are generally more computationally intensive than fluid models The may be used to describe the dynamics of a system of charged particles interacting with an electromagnetic field ක ත ම ප ල ස ම Most artificial plasmas are generated by the application of electric and or magnetic fields Plasma generated in a laboratory setting and for industrial use can be generally categorized by The type of power source used to generate the plasma DC RF and microwave The pressure at which they operate vacuum pressure lt 10 mTorr moderate pressure 1 Torr and atmospheric pressure 760 Torr The degree of ionization within the plasma fully ionized partially ionized weakly ionized The temperature relationships within the plasma Thermal plasma Te Tion Tgas Non Thermal or cold plasma Te gt gt Tion Tgas The electrode configuration used to generate the plasma The magnetization of the particles within the plasma Magnetized both ion and electrons are trapped in by the magnetic field partially magnetized the electrons but not the ions are trapped by the magnetic field non magnetized the magnetic field is too weak to trap the particles in orbits but may generate Lorentz forces Its applicationExamples of industrial commercial plasma Low pressure discharges plasmas non thermal plasmas generated by the application of DC or low frequency RF lt 100 kHz electric field to the gap between two metal electrodes Probably the most common plasma this is the type of plasma generated within tubes CCP similar to glow discharge plasmas but generated with high frequency RF electric fields typically 13 56 MHz These differ from glow discharges in that the sheaths are much less intense These are widely used in the microfabrication and integrated circuit manufacturing industries for plasma etching and plasma enhanced chemical vapor deposition ICP similar to a CCP and with similar applications but the electrode consists of a coil wrapped around the discharge volume which inductively excites the plasma similar to CCP and ICP in that it is typically RF or microwave but is heated by both electrostatic and electromagnetic means Examples are ECR and ICR These typically require a coaxial magnetic field for wave propagation Atmospheric pressure this is a high power thermal discharge of very high temperature 10 000 K It can be generated using various power supplies It is commonly used in processes For example it is used to melt rocks containing Al2O3 to produce aluminium this is a non thermal discharge generated by the application of high voltage to sharp electrode tips It is commonly used in generators and particle precipitators DBD this is a non thermal discharge generated by the application of high voltages across small gaps wherein a non conducting coating prevents the transition of the plasma discharge into an arc It is often mislabeled Corona discharge in industry and has similar application to corona discharges It is also widely used in the web treatment of fabrics The application of the discharge to synthetic fabrics and plastics functionalizes the surface and allows for paints glues and similar materials to adhere Fields of active research The electric field in a plasma is so effective at accelerating ions that electric fields are used in This is just a partial list of topics A more complete and organized list can be found on the Web site for Plasma science and technology Plasma theory Plasma interactions with waves and beams Plasmas in nature The Earth s Space plasmas e g Earth s an inner portion of the dense with plasma Industrial plasmasradar Plasma applications MFE tokamak IFE also Inertial confinement fusion ICF Food processing aka cold plasma convert waste into reusable material with plasma ම ව ත බලන නPhysics ද ව රය plasma යන න න දහස ශබ දක ෂය වන ව ක ෂනර ය ද ස ය බලන න ප ල ස ම භ ත ක ව ද ය ව හ සබ ඳ ම ධ ය ව ක ම ධ ය ක මන ස හ ඇත සටහන IPPEX Glossary of Fusion Terms http ippex pppl gov fusion glossary html ප රත ෂ ඨ පනය 2008 08 23 Plasma fountain Source press release Solar Wind Squeezes Some of Earth s Atmosphere into Space R O Dendy Plasma Dynamics Hillary Walter Michelle Cooper Illustrated Dictionary of Physics Daniel Hastings Henry Garrett Spacecraft Environment Interactions After Peratt A L Advances in Numerical Modeling of Astrophysical and Space Plasmas 1966 Astrophysics and Space Science v 242 Issue 1 2 p 93 163 See The Nonneutral Plasma Group 2017 07 18 at the Wayback Machine at the University of California San Diego See Flashes in the Sky Earth s Gamma Ray Bursts Triggered by Lightning Richard Fitzpatrick Introduction to Plasma Physics Magnetized plasmas Hong Alice 2000 Dielectric Strength of Air The Physics Factbook Dickel J R The Filaments in Supernova Remnants Sheets Strings Ribbons or 1990 Bulletin of the American Astronomical Society Vol 22 p 832 Grydeland T et al Interferometric observations of filamentary structures associated with plasma instability in the auroral ionosphere 2003 Geophysical Research Letters Volume 30 Issue 6 pp 71 1 Moss Gregory D et al Monte Carlo model for analysis of thermal runaway electrons in streamer tips in transient luminous events and streamer zones of lightning leaders 2006 Journal of Geophysical Research Volume 111 Issue A2 CiteID A02307 Doherty Lowell R Filamentary Structure in Solar Prominences 1965 Astrophysical Journal vol 141 p 251 Hubble views the Crab Nebula M1 The Crab Nebula Filaments http seds lpl arizona edu messier more m001 hst html ප රත ෂ ඨ පනය 2009 10 05 Zhang Yan An et al A rope shaped solar filament and a IIIb flare 2002 Chinese Astronomy and Astrophysics Volume 26 Issue 4 p 442 450 Hannes Alfven Cosmic Plasma 1981 See section VI 13 1 Cellular Structure of Space R G Greaves M D Tinkle and C M Surko Creation and uses of positron plasmas Physics of Plasmas May 1994 Volume 1 Issue 5 pp 1439 1446 See Evolution of the Solar System 1976 Web site for Plasma science and technology 2015 05 09 at the Wayback Machineබ හ රට ය ම Plasmas the Fourth State of Matter Animation on the plasma excitation 2009 01 30 at the Wayback Machine Plasma Science and Technology Plasma on the Internet comprehensive list of plasma related links Introduction to Plasma Physics Graduate course given by Richard Fitzpatrick 2010 01 04 at the Wayback Machine M I T Introduction by I H Hutchinson NRL Plasma Formulary online 2007 04 28 at the Wayback Machine or an html version 2007 02 08 at the Wayback Machine Plasma Coalition page Plasma Material Interaction 2005 03 08 at the Wayback Machine How to make a glowing ball of plasma in your microwave with a grape 2005 09 06 at the Wayback Machine More Video How to make plasma in your microwave with only one match video Plasma Ignition How to make a plasma ignition system Video U S Dept of Agriculture research project Decontamination of Fresh Produce with Cold Plasma CNRS LAEPT Electric Arc Thermal Plasmas 2012 01 27 at the Wayback Machine french