All articles starting with P
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Plasma (physics)
Plasma, the fourth state of matter after solid, liquid, and gas, is an ionized gas of ions and free electrons making up 99% of visible matter, including stars.
Plasma ablation
Plasma ablation is the removal of surface material by plasma, combining ion bombardment with chemical conversion to volatile products; the literature usually calls it plasma etching.
Plasma acceleration
Plasma acceleration is an accelerator-physics method that uses plasma-wave electric fields, driven by a laser pulse or particle beam, to accelerate charged particles at gradients hundreds of times beyond conventional radio-frequency accelerators.
Plasma activation
Plasma activation is a surface-treatment method that uses cold gas plasma to create reactive functional groups in a material's outer few nanometers, improving wettability, adhesion, and coating performance.
Plasma actuator
A plasma actuator is a flow-control device that uses an electrical discharge in air to impart momentum to a gas flow without moving parts, most often a dielectric barrier discharge.
Plasma arc gasification
Plasma arc gasification is a waste treatment process in which a plasma torch breaks organic waste down into syngas while melting the inorganic fraction into a glassy, leach-resistant slag.
Plasma arc welding
Plasma arc welding (PAW) is an arc welding process in which a constricted arc through a copper nozzle makes deep, narrow single-pass welds, developed from TIG welding in the 1950s.
Plasma beta
Plasma beta (β), in plasma physics, is the ratio of a plasma's thermal pressure to its magnetic pressure; values above 1 mean the plasma governs the field's behavior.
Plasma catalysis
Plasma catalysis is the coupling of non-thermal plasma with catalytic materials to drive chemical reactions such as CO2 conversion, nitrogen fixation, and methane reforming with electricity.
Plasma cell
Plasma cell, or plasmacyte: terminally differentiated B lymphocyte secreting antibodies; short-lived plasmablasts versus long-lived bone marrow plasma cells; key markers CD138/CD38; basis of multiple myeloma.
Plasma cell leukemia
Plasma cell leukemia (PCL), primary or secondary, is a rare, aggressive plasma cell dyscrasia related to multiple myeloma, now defined by the IMWG as 5% or more circulating plasma cells in peripheral blood, with poor survival despite proteasome inhibitors and transplantation.
Plasma cell neoplasms
Plasma cell neoplasms are clonal plasma cell disorders ranging from MGUS through smoldering myeloma to multiple myeloma, in which abnormal plasma cells form tumors in bone or soft tissue.
Plasma channel
A plasma channel is an elongated plasma column with lowest density on axis that guides intense laser pulses over many Rayleigh lengths, chiefly in laser wakefield accelerators.
Plasma chemistry
Plasma chemistry, a field within physical chemistry and plasma science, studies chemical reactions in ionized gases, enabling semiconductor etching, CO2 conversion, water purification, and plasma medicine.
Plasma cleaning
Plasma cleaning is a surface treatment method that uses ionized gas to remove organic contaminants, oxide films, and processing residues before bonding, coating, or assembly, widely used in semiconductor manufacturing.
Plasma control
Plasma control is the set of real-time feedback techniques used to confine, shape, and stabilize the plasma inside tokamaks, coordinating magnetic coils thousands of times per second.
Plasma crystal
A plasma crystal, also called a Coulomb crystal, is an ordered lattice of charged microparticles that forms in a dusty plasma, first observed in 1994.
Plasma cutting
Plasma cutting, also called plasma arc cutting, is a thermal process that cuts conductive metals such as steel, stainless steel, and aluminum with a jet of ionized gas.
Plasma diagnostics
Plasma diagnostics are experimental techniques used to measure plasma physical quantities, such as electron density, ion temperature, and magnetic fields, primarily using electromagnetic waves like microwaves.
Plasma diagnostics in space and low-temperature plasmas
Plasma diagnostics in space and low-temperature plasmas are measurement techniques, such as Langmuir probes and laser Thomson scattering, for electron density, temperature, and potential in the ionosphere, solar wind, and laboratory low-temperature plasmas.
Plasma dispersion function
The plasma dispersion function Z(ζ) is a complex special function introduced by Fried and Conte in 1961 for calculating wave propagation in a Maxwellian collisionless plasma.
Plasma display
A plasma display is a flat-panel display in which each pixel is a tiny cell of noble gas whose discharge excites phosphors, invented in 1964.
Plasma doping
Plasma doping (PLAD), also called plasma immersion ion implantation (PIII), is a semiconductor doping technique where a pulsed wafer bias implants ions from a plasma directly.
Plasma electrolytic oxidation
Plasma electrolytic oxidation (PEO), also called micro-arc oxidation, is an electrochemical process using high-voltage sparking to grow hard ceramic coatings on light metals such as aluminum, titanium, and magnesium.
Plasma etching
Plasma etching, also called dry etching, is a semiconductor manufacturing process that removes wafer material with reactive gas plasma, producing vertical, anisotropic profiles wet etching cannot.
Plasma exchange
Plasma exchange, also called therapeutic plasma exchange or plasmapheresis, is a procedure that removes a patient's plasma and replaces it with albumin or donor plasma.
Plasma focus
A plasma focus, or dense plasma focus (DPF), is a pulsed-power device in which a high-current discharge collapses plasma onto the axis, emitting X-rays, ions, and neutrons.
Plasma frequency
The plasma frequency is the natural frequency at which electrons in a plasma collectively oscillate against heavy ions; radio waves below it are reflected, which lets the ionosphere bounce shortwave signals.
Plasma globe
A plasma globe, also called a plasma ball or plasma lamp, is a clear glass sphere whose central electrode sends glowing electric filaments to the inner glass surface.
Plasma imaging and tomography
Plasma imaging and tomography are plasma diagnostics in which cameras and detector arrays record radiation along many lines of sight, and tomographic inversion reconstructs the emitting material's distribution.