Gallium is one of four metals which can be liquid at room temperature
Chemical formula for Gallium III Iodide.
Chemical formula for Gallium III Oxide.
Chemical formula for Gallium III Selenide.
Chemical formula for Gallium III Telluride.
Abbreviation of Glacial Acetic Acid.
Chemical formula for Gallium Arsenide.
Gable Wall
The triangular wall beneath the end of a gable roof.
Chemical formula for Gallium III Bromide.
Chemical formula for Gallium III Chloride.
A silvery white metal which is ductile and malleable. It is stable in a dry atmosphere but forms an oxide coating when exposed to moist air.
Gadolinium III Chloride


A colourless, hygroscopic, water-soluble solid.

Chemical formula for Gallium III Fluoride.
The ratio of the output level of a circuit to the input. This will be positive for an amplifier and negative for an attenuator.
Gain Bandwidth Product
The number that results when the gain of a circuit is multiplied by the bandwidth of that circuit.
Abbreviation of gallon.
Galactic Corona
A huge spherical region that exists around our own and other spiral galaxies.
Galactic Disc
The plane in which the spiral arms of spiral galaxies or barred spiral galaxies exist.
Galactic Year
The unit of time in which the Solar System makes one revolution around the Milky Way galaxy.
A system of about 100 billion stars.
Galaxy Clusters
Groups of galaxies that may contain up to a few thousand galaxies.
A Lead Sulphide and the most common ore of lead.
Galilean Principle of Relativity
The laws of motion are the same in all inertial reference systems.
The CGS unit of acceleration, one galileo is an acceleration of 1 centimetre per second per second.
Galileo Galilei
Astronomer, mathematician and physicist he dwelt, not on the useless question, why do things happen? but, how do things happen?
A severe form of adhesive wear which occurs during sliding contact of one surface relative to another.
One of four metals which can be liquid at room temperature.
Gallium Arsenide


A crystalline, high-efficiency compound used to make certain types of solar cells and semiconductor material.

Gallium II Selenide


Has been used as a non-linear optical material.

Gallium II Telluride


Made by reacting the elements or by metal organic vapour deposition.

Gallium III Bromide


White powder that is soluble in water.

Gallium III Chloride


The main precursor to most derivatives of gallium and a reagent in organic synthesis.

Gallium III Fluoride


White solid.

Gallium III Hydroxide


The normal form of Gallium in the Earth′s crust.

Gallium III Iodide


The most common iodide of gallium.

Gallium III Oxide


White crystalline powder prepared by thermal decomposition of gallium salts.

Gallium III Selenide


P-type semiconductor. Reddish-black crystals with a slight garlic odour.

Gallium III Telluride


Used as a semiconductor.

Gallium Monoselenide
Alternative name for Gallium II Selenide.
Gallium Nitride


A binary III/V direct bandgap semiconductor commonly used in bright light-emitting diodes.

Gallium Phosphide


Used in the manufacture of low-cost red, orange, and green light-emitting diodes.

Gallium Sesquioxide
Alternative name for Gallium III Oxide.
Gallium Tribromide
Alternative name for Gallium III Bromide.
Gallium Trichloride
Alternative name for Gallium III Chloride.
Gallium Trifluoride
Alternative name for Gallium III Fluoride.
Gallium Trihydroxide
Alternative name for Gallium III Hydroxide.
Gallium Triiodide
Alternative name for Gallium III Iodide.
Gallium Trioxide
Alternative name for Gallium III Oxide.
Gallium Triselenide
Alternative name for Gallium III Selenide.
This unit of volume is defined in the British and American system of units. Note 1 UK gallon = 1.2 US gallons.
Gallons per Minute
Volume flow rate.
Galloway Tubes
Tapered thermic syphon water-tubes inserted in the furnace of a Lancashire boiler.
Galvanic Cell
A cell in which chemical change is the source of electrical energy.
Galvanic Corrosion
Corrosion associated with the current of a galvanic cell consisting of two dissimilar conductors in an electrolyte or two similar conductors in dissimilar electrolytes.
Galvanic Couple
A pair of dissimilar conductors, commonly metals, in electrical contact.
Galvanic Current
The electric current that flows between metals or conductive nonmetals in a galvanic couple.
Galvanic Series
This determines the nobility of metals and semi-metals and ranks them, note that this rank is dependent on the electrolyte that the metal is submerged in.
To coat a metal surface with zinc using various processes.
An instrument for detecting and measuring a small electric current by movements of a magnetic needle or of a coil in a magnetic field.
An archaic name for Electroforming.
An electronic instrument that controls the current through an electrochemical cell at a preset value, as long as the needed cell voltage and current do not exceed the compliance limits of the galvanostat.
Galvanostatic Technique
An electrochemical measuring technique for electrochemical analysis or for the determination of the kinetics and mechanism of electrode reactions based on the control of the current flowing through the system.
Game Theory
A branch of mathematics that seeks to model decision making in conflict situations.
A reproductive cell, in humans the male cell is a sperm the female cell is the ovum.
A letter of the Greek alphabet.
Gamma Iron
The face-centered cubic form of pure iron, stable from 910 to 1400C.
Gamma Rays
Gamma rays are electromagnetic waves or photons emitted from the nucleus (centre) of an atom.
Gamma Stirling Engine
A beta Stirling engine in which the power piston is not mounted coaxially to its displacer piston.
Gamme Ring Armature
An inefficient type of armature winding in which many of the turns are shielded from the field by its own iron ring.
Chemical formula for Gallium Nitride.
Gang Milling
A milling setup where a number of cutters are arranged on an arbor so that several surfaces can be machined at one time.
Ganged Tuning
The process used to tune two or more circuits with a single control.
Gantt Chart
Graph showing steps of plan and durations.
Chemical formula for Gallium Phosphide.
A spout placed on the roof gutter of a Gothic building to carry away rainwater, commonly carved fancifully as in the shapes of animal heads.
Matter with no definite shape or volume.
Gas Bearing
A journal or thrust bearing lubricated with gas.
Gas Cap
The gas immediately in front of a body as it travels through the atmosphere.
Gas Constant
Molar Gas Constant, R = 8.31441 JK-1mol-1
Gas Diffusion
Mixing of two gases caused by random molecular motions.
Gas Laser
A type of laser in which the laser action takes place in a gas medium.
Gas Laws
The thermodynamic laws applying to perfect gases.
Gas Mark
Gas cooker temperature scale.
Gas Metal Arc Welding
An arc welding process that produces coalescence of metals by heating them with an arc between a continuous filler metal electrode and the work pieces.
Gas Pedal
A pedal that when pressed is connected to the engine and demands more torque.
Gas Pocket
A weld cavity caused by the trapping of gases released by the metal when cooling.
Gas to Liquid Technology
Gas-to-liquid conversion technologies that use chemical or physical means to convert natural gas to a liquid form suitable for road transport or direct use.
Gas Turbine
A turbine driven by the expansion of burning fuel.
Gas Turbine Efficiency
For a simple cycle gas turbine the efficiency is determined by the pressure ratio of the compressor.
Gas Welding
A process in which the welding heat is obtained from a gas flame.
Chemical formula for Gallium II Selenide.
A process for converting materials such as coal, petroleum, or biomass, into carbon monoxide and hydrogen by reacting the raw material at high temperatures with a controlled amount of oxygen.
A thin layer of material placed between two surfaces or joints to make a tight seal.
Ethanol mixture that contains 10% ethanol, 90% unleaded gasoline.
Gasoline Gallon Equivalent
A unit for measuring alternative fuels so that they can be compared with gasoline on an energy equivalent basis.
One of the terminals of a Field Effect Transistor (FET).
Gate Valve
A straight through pattern valve in which closure element is a wedge situated between two fixed seating surfaces, with means to move it in or out of the flow stream in a direction perpendicular to the pipeline axis.
Chemical formula for Gallium II Telluride.
Gated Automatic Gain Control
Circuit that permits automatic gain control to function only during short time intervals.
Any hardware or software that is used for the purpose of providing access from one system to another.
The process of selecting those portions of a wave that exist during one or more selected time intervals or that have magnitudes between selected limits.
Commonly used to describe the thickness of sheet material.
Gauge Blocks
Steel blocks machined to extremely accurate dimensions.
Gauge Glass
Part of the water level gauge, which normally consists of a vertical glass tube connected top and bottom to the boiler backplate.
Gauge Pressure
Zero referenced against ambient air pressure, so it is equal to absolute pressure minus atmospheric pressure.
A unit of magnetic field strength, 10-4 tesla.
Gauss Law for Magnetic Fields
The magnetic flux through a closed surface is zero; no magnetic charges exist.
Gaussian Curve
Normal Distribution.
Gaussian Distribution
A continuous probability distribution that often gives a good description of data that cluster around the mean.
Gaussian Noise
Another name for Random Noise.
Gaussian Optics
Optical characteristics limited to infinitesimally small pencils of light.
Gauss′s Law
The electric flux through a closed surface is proportional to the algebraic sum of electric charges contained within that closed surface.
Gay-Lussac, Joseph Louis
Developed the law of volumes concerning the combination of gases and discovered boron.
Gay-Lussac′s Law
When gases react, they do so in a definite proportion by volume, if the volumes are measured at the same pressure and temperature.