A distillate of petroleum which is used in spark ignition internal combustion engines. Ignition qualities are measured with an octane number.

Excessive battery charging causes electrolysis, emitting hydrogen and oxygen.

A valve which permits for uninterrupted flow when open; see Stop valves.

An instrument or device for measuring, indicating or comparing a physical characteristic.

A glass tube or arrangement of glass plates fitted to a gauge used to give a visual indication of the level of liquid in a tank, pressure vessel, or boiler.

Gauge pressure is zero-referenced against ambient air pressure, so it is equal to absolute pressure minus atmospheric pressure.

1. Tank gauging, level gauging – the process of measuring tank contents. 2. Thickness measurements which are carried out to evaluate the corrosion wastage of hull structure.

Closed gauging device – A device which is separated from the tank atmosphere and keeps tank contents from being released.

Electro-pneumatic system – This system involves blowing air down the pipe to the liquid in the tank and measuring the pressure needed to force the liquid out of the pipe.

GE Wind Energy is a branch of GE Renewable Energy, a subsidiary of General Electric.

In conventional wind turbines, the blades spin a shaft that is connected through a gearbox to the generator.

This is the simplest form of rotary positive-displacement pumps.

A vessel equipped to load and discharge by its own means (derricks or cranes).

A vessel not equipped to load and discharge by its own means (without derricks or cranes).

Gearless wind turbines (also called direct drive) get rid of the gearbox completely.

A Geiger counter is an instrument used for detecting and measuring ionizing radiation.

A gel is a semi-solid that can have properties ranging from soft and weak to hard and tough. Gels are defined as a substantially dilute cross-linked system, which exhibits no flow when in the steady-state.

A modern gel battery is a VRLA battery with a gelified electrolyte; the sulfuric acid is mixed with fumed silica, which makes the resulting mass gel like and immobile.

The gel point is an abrupt change in the viscosity of a solution containing a polymer.

Gelation (gel transition) is the formation of a gel from a system with polymers.