Is an apparatus that exposes bubbles near the top of a liquid layer that enables mass transfer between the liquid and air signified by increased turbulence across the exposed surface area of the liquid.

Is an apparatus that exposes bubbles near the top of a liquid layer that enables mass transfer between the liquid and air signified by increased turbulence across the exposed surface area of the liquid.

Equipment used to direct surface water flow.

Equipment used to direct surface water flow.

A physical object that is protecting against a large but momentary increase in the voltage of an electric circuit.

A physical object that is protecting against a large but momentary increase in the voltage of an electric circuit.

Is a vessel used in fluid systems to absorb sudden surges of fluid to stabilize the pressure in the system and prevent damage to pipes and equipment.

Is a vessel used in fluid systems to absorb sudden surges of fluid to stabilize the pressure in the system and prevent damage to pipes and equipment.

A check valve that is a check valve where the closure member is a disc which swings freely on a hinge and which opens automatically when flow is established and closes automatically when flow ceases or is reversed.

A check valve that is a check valve where the closure member is a disc which swings freely on a hinge and which opens automatically when flow is established and closes automatically when flow ceases or is reversed.

A switchgear and controlgear bearing a set of switches for connecting and disconnecting the various circuits of an electrical system, as of a telegraph, telephone, etc.

A switchgear and controlgear bearing a set of switches for connecting and disconnecting the various circuits of an electrical system, as of a telegraph, telephone, etc.

A physical object that is a general term covering switching devices and their combination with associated control, measuring, protective and regulating equipment, also assemblies of such devices and equipment with associated interconnections, accessories, enclosures and supporting structures.

A physical object that is a general term covering switching devices and their combination with associated control, measuring, protective and regulating equipment, also assemblies of such devices and equipment with associated interconnections, accessories, enclosures and supporting structures.

An artefact joining two parts so that one or both can pivot freely (as on a bolt or pin).

An artefact joining two parts so that one or both can pivot freely (as on a bolt or pin).

An instrument panel dedicated to a particular system.

An instrument panel dedicated to a particular system.

A vessel intended to contain fluid for storage. Typically a receiving or collecting function for further distribution. Typically with a vertical and cylindrical or square shape and a flat or conical bottom.

A vessel intended to contain fluid for storage. Typically a receiving or collecting function for further distribution. Typically with a vertical and cylindrical or square shape and a flat or conical bottom.

A fluid regulator that controls the flow of liquid or gas from a pipe or container. Taps are often attached to a sink or bath.

A fluid regulator that controls the flow of liquid or gas from a pipe or container. Taps are often attached to a sink or bath.

A physical object that converts sound signals into corresponding variations of electric current (or potential), which is transmitted by wire or radio to a distant point where it is reconverted into sound.

A physical object that converts sound signals into corresponding variations of electric current (or potential), which is transmitted by wire or radio to a distant point where it is reconverted into sound.