All articles starting with P
28,818 articles
Pressure Cooker
Pressure Cooker is a 2023 Netflix reality cooking competition in which 11 American chefs live together, cook timed challenges, judge each other's dishes, and vote for the $100,000 winner; Robbie Jester won the eight-episode first season.
Pressure cooker bomb
A pressure cooker bomb is an improvised explosive device made from a household pressure cooker filled with explosive and shrapnel, used in the 2013 Boston Marathon bombing.
Pressure gap
The pressure gap is the difference in behavior between catalysts studied under ultra-high vacuum and the same materials at the high pressures and temperatures of industrial reactors.
Pressure gradient measurement
Pressure gradient measurement is the clinical measurement of the pressure difference across a narrowed heart valve or vessel, done by Doppler echocardiography or catheterization to grade stenosis severity.
Pressure head
Pressure head, also called static head, is the height of a fluid column that would produce a given pressure, equal to pressure divided by the fluid's weight density.
Pressure leaching
Pressure leaching is a hydrometallurgical process in which ores are dissolved in a pressurized autoclave above boiling point, first commercialized in the Bayer process in 1892.
Pressure measurement
Pressure measurement is the determination of the force exerted by a fluid per unit area, measured in pascals with instruments from manometers and piston gauges to Bourdon tubes.
Pressure oxidation
Pressure oxidation (POX) is a hydrometallurgical process that oxidizes metal sulfides in a sealed autoclave at elevated temperature and oxygen pressure, used mainly to free gold occluded in refractory ores.
Pressure ratio
Pressure ratio is the ratio of total pressure at two stations of an engine or machine, quantifying how much a compressor or whole engine raises the pressure of the gas flow.
Pressure regulator
A pressure regulator, also called a pressure-reducing valve, is a mechanical device that holds gas or liquid pressure at a set value without external power.
Pressure retarded osmosis
Pressure retarded osmosis (PRO), also called osmotic power or blue energy, is a membrane process that generates electricity from the salinity difference between fresh water and pressurized salt water.
Pressure ridge (ice)
A pressure ridge is a wall of broken sea ice pushed up and down when ice floes compress, with a sail above water and a much larger keel below.
Pressure solution
Pressure solution is a geologic deformation process in which mineral grains dissolve where they touch under high stress, then reprecipitate on low-stress grain faces, reducing porosity.
PRESSURE study
PRESSURE study (NCT07059520): Erasmus MC-led prospective observational cohort of 125 chronic mesenteric ischemia patients testing whether vasodilator-stimulated translesional Pd/Pa pressure measurements predict benefit from mesenteric stenting, building on a retrospective study with 86% sensitivity and 83% specificity.
Pressure support ventilation
Pressure support ventilation (PSV) is a mode of mechanical ventilation in which every breath is patient-triggered and assisted with a set inspiratory pressure, used for weaning.
Pressure suppression pool
A pressure suppression pool is a pool of water inside a boiling water reactor's containment that condenses steam released during an accident, limiting containment pressure.
Pressure swing adsorption
Pressure swing adsorption (PSA) is a gas separation technique that regenerates its adsorbent by pressure reduction, used industrially for air separation, gas drying, and hydrogen purification.
Pressure swing distillation
Pressure swing distillation is a chemical engineering technique that separates homogeneous azeotropic mixtures by running two columns at different pressures, so pure products can be withdrawn without adding a solvent.
Pressure testing
Pressure testing is an engineering verification method that applies internal pressure, usually with water or gas, to vessels and piping to confirm strength and leak-tightness.
Pressure Transducers
Pressure transducers convert applied pressure, usually via a deflecting diaphragm, into an electrical signal. Also called pressure sensors or transmitters; main types are piezoresistive, capacitive, piezoelectric, and triboelectric, used from industrial process control to invasive blood pressure monitoring.
Pressure transient analysis
Pressure transient analysis (PTA) is a well testing method that interprets pressure changes measured in a well over time to estimate permeability, skin factor, and reservoir pressure.
Pressure ulcer
Pressure ulceration (bedsore, pressure injury, decubitus ulcer; ICD-11 EH90) is localized skin and tissue death from prolonged pressure and shear over bony prominences, staged 1-4 plus deep tissue injury by the NPIAP system.
Pressure vessel
A pressure vessel is a closed container designed to hold gases or liquids at pressures substantially different from ambient pressure, in applications from chemical plants to submarines.
Pressure-controlled scanning calorimetry
Pressure-controlled scanning calorimetry (PCSC) is a calorimetric technique in which pressure, rather than temperature, is scanned, revealing how pressure shifts phase transitions like fusion and lipid melting.
Pressure-fed engine
A pressure-fed engine, also called a pressure-fed rocket engine, is a liquid rocket engine in which tank pressure, usually from helium, feeds propellants into the thrust chamber without a turbopump.
Pressure-flow study
A pressure-flow study is an invasive urodynamic test that records bladder pressure and urine flow simultaneously during voiding, the reference standard for diagnosing bladder outlet obstruction in men.
Pressure-gain combustion
Pressure-gain combustion is a combustion mode in which pressure rises across the combustor instead of falling, pursued to improve gas turbine efficiency since the 1950s.
Pressure-induced amorphization of metal–organic frameworks
Pressure-induced amorphization of metal–organic frameworks (MOFs) is the abrupt loss of crystallinity when these porous solids are compressed, typically below 1 GPa, used to trap guest molecules and make amorphous MOFs.
Pressure-induced localized lipoatrophy
Pressure-induced localized lipoatrophy, also called lipoatrophia semicircularis or semicircular lipoatrophy, is a rare acquired localized lipodystrophy causing band-like thigh depressions from repeated pressure, first described in 1974, mainly in female office workers, and reversible when pressure stops.
Pressure-induced phase transitions in hybrid perovskites
Pressure-induced phase transitions in hybrid perovskites are structural transformations of soft organic–inorganic perovskites under hydrostatic pressure, often applied in diamond anvil cells, that tilt octahedra, reorder organic cations, and narrow bandgaps.