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Pulse-width modulation
Pulse-width modulation (PWM), also called pulse-duration modulation, is a power-control method that switches a load fully on and off rapidly, setting average power by duty cycle.
Pulsed column
A pulsed column, or pulsed extraction column, is a vertical liquid–liquid extraction contactor that mixes two liquids with a reciprocating pulse, used mainly in PUREX nuclear reprocessing.
Pulsed eddy current
Pulsed eddy current (PEC) is a non-destructive testing method that measures wall thickness of insulated steel pipes and vessels to find corrosion while in service.
Pulsed laser ablation
Pulsed laser ablation is a materials processing method that removes material from a target surface using short, intense laser pulses, producing vapor, machined micro-features, or colloidal nanoparticles synthesized in liquids.
Pulsed laser deposition
Pulsed laser deposition (PLD) is a physical vapor deposition technique that uses laser pulses to ablate a target, depositing thin films valued for complex oxides and superconductors.
Pulsed plasma thruster
A pulsed plasma thruster (PPT) is an electric rocket engine that produces tiny pulses of thrust by discharging a capacitor across solid Teflon propellant, used for small-satellite attitude control since 1964.
Pulsed thermography
Pulsed thermography is an active infrared nondestructive testing method: a short light pulse heats a surface, and an infrared camera records the cooling to reveal subsurface defects.
Pulsejet
A pulsejet, or pulse jet engine, is an air-breathing jet engine that produces thrust through intermittent combustion, best known in the Argus As 014 that powered the V-1 flying bomb.
PULSTAR
PULSTAR is a 1-megawatt pool-type nuclear research reactor at North Carolina State University in Raleigh, operating since 1972 and used for research, education, and operator training.
Pulteney Bridge
Pulteney Bridge is a shop-lined stone bridge over the River Avon in Bath, England, designed by Robert Adam and built between 1769 and 1774 for William Johnstone Pulteney.
Pultrusion
Pultrusion is a continuous manufacturing process that pulls reinforcing fibers through a resin bath and a heated die to produce fiber-reinforced polymer composite profiles of constant cross-section.
Pulumi
Pulumi is an open-source infrastructure as code tool, launched in 2018 by Pulumi Corporation of Seattle, that lets developers manage cloud infrastructure using general-purpose programming languages.
Pulverized coal combustion
Pulverized coal combustion (PCC) burns coal ground to a fine powder and blown with air into a furnace, and is the dominant technology for coal-fired power generation worldwide.
Pump
A pump is a machine that raises a liquid to higher pressure or head. Its two families, rotodynamic and positive displacement, differ in how they move fluid.
Pump action
The pump action, also called a slide action, is a firearm mechanism in which the shooter slides a fore-end under the barrel to eject and chamber each round, as in shotguns.
Pump as turbine
A pump as turbine (PAT) is a standard hydraulic pump operated in reverse so pressurized water drives the impeller, turning the motor into a generator for micro-hydropower.
Pump laser
A pump laser is a laser, most often a semiconductor diode, that excites a gain medium such as erbium-doped fiber, enabling optical amplifiers and fiber lasers to work.
Pump sump
A pump sump is the reservoir, or lower portion of a wet well, from which a pump draws water, designed to deliver steady, swirl-free flow to the pump suction inlet.
Pump-controlled actuator
A pump-controlled actuator is a hydraulic actuator, most often a cylinder, whose speed and force are set by varying the flow its pump delivers rather than by throttling valves.
Pump-jet
A pump-jet, also called a hydrojet, is a marine propulsion device that accelerates water through a ducted rotor and stator, widely fitted to submarines and torpedoes.
Pump.fun
Pump.fun is a Solana blockchain launchpad, live since January 2024, that lets anyone create a tradeable token in minutes; it deployed 5.3 million tokens in 2024.
Pumped fluid loop thermal control
Pumped fluid loop thermal control is an active spacecraft thermal control technique in which a pump circulates fluid to collect heat and reject it at a radiator.
Pumped thermal electricity storage
Pumped thermal electricity storage (PTES), also called pumped heat energy storage (PHES), stores grid electricity as heat in cheap materials like rocks or molten salts, then reconverts it with a heat engine.
Pumped-storage hydroelectricity
Pumped-storage hydroelectricity (PSH), also known as pumped hydro storage, is a form of hydroelectric energy storage that pumps water uphill and releases it through turbines to generate power.
Pumping losses
Pumping losses, also called gas-exchange losses, are the work a piston engine expends moving gases through intake and exhaust strokes instead of producing useful output.
Pumping station
A pumping station, also called a pump station or pump house, houses pumps that move water, sewage, or other liquids between elevations or pressure zones.
Pumpjack
A pumpjack, also known as a horsehead pump or nodding donkey, is the surface machine that drives a plunger pump to lift oil from a well.
Puna Geothermal Venture
Puna Geothermal Venture (PGV) is a geothermal power plant in the Puna District of Hawaii Island, the state's only geothermal plant, opened in 1993 and owned by Ormat Technologies.
Punakha Suspension Bridge
The Punakha Suspension Bridge is a pedestrian footbridge crossing the Pho Chhu river below Punakha Dzong in Bhutan, built in 1994 and described as the country's longest suspension bridge.
Punatsangchhu II hydroelectric plant
Punatsangchhu-II Hydroelectric Project is a 1,020 MW run-of-the-river plant on the Punatsangchhu river in western Bhutan, funded jointly by Bhutan and India and inaugurated in November 2025.