An emissions cleaning process whereby NOx is reduced by a catalyst, combined with a reagent that is either an aqueous solution of urea or ammonia.

The Selective Catalytic Reduction system reduces the level of nitrogen oxide in the exhaust gas from the engine by means of catalyst elements and a reducing agent.

In solar thermal collectors, a selective surface or selective absorber is a means of increasing its operation temperature and/or efficiency.

Self-discharge is a phenomenon in batteries in which internal chemical reactions reduce the stored charge of the battery without any connection between the electrodes or any external circuit. Self-discharge decreases the shelf life of batteries and causes them to have less than a full charge when actually put to use.

A paint coating which is designed to wear down smoothly while maintaining a bio-active interface between the coating and water.

A tank used for the carriage of liquefied gas. It is strong enough by virtue of its construction to accept any loads imposed on it by the cargo.

A cargo hold with a large hatch to enable the loading of loose bulk cargoes and directing it into all parts of the hold.

The self-unloading collier HAI WANG XING was built by Bremer Vulkan Verft, Germany, in 1995. Cargo is carried in five holds within a double-hull.

Horizontal and vertical conveyor systems used to discharge bulk cargoes.

The access system for oil platforms and other off shore installations that enables personnel to reach operational and accommodation spaces safely from the sea level.

A semi-arid climate, semi-desert climate, or steppe climate is the climate of a region that receives precipitation below potential evapotranspiration, but not as low as a desert climate.

Manual welding with equipment that automatically controls welding conditions.

Semiconductors are materials which have a conductivity between conductors and nonconductors or insulators. Used to control current in circuits.

Semiheavy water is the result of replacing one of the protium in light water with deuterium.

Delivered by Hudong-Zhonghua Shipyard in 2002, the NORGAS ORINDA is the innovative and highly efficient gas carrier.

A semi-submersible platform is a specialised marine vessel used in offshore roles including as offshore drilling rigs, safety vessels, oil production platforms, and heavy lift cranes.

see Heavy lift ships.

Sensible heat is heat exchanged by a body or thermodynamic system in which the exchange of heat changes the temperature of the body or system, and some macroscopic variables of the body or system, but leaves unchanged certain other macroscopic variables of the body or system, such as volume or pressure.

A sensor is a device, module, machine, or subsystem whose purpose is to detect events or changes in its environment and send the information to other electronics.

Separate” means that a cargo piping system or cargo vent system, for example, is not connected to another cargo piping or cargo vent system.