CHEMISTRY GLOSSARY

reverse osmosis    →   reverzna osmoza

Reverse osmosis is the method used for obtaining freshwater from saltwater. The process uses a semi-permeable membrane through which pure water and not the salts will pass. The saltwater must be pressurised to approximately 25 bar, which makes it operationally expensive to produce large quantities of fresh water by this method.

salinisation    →   salinizacija

Salinisation is the increase in salinity of fresh surface and ground water supplies.

sand filtration    →   pješčana filtracija

Sand filtration is a frequently used and very robust method of removing suspended solids from water. The filtration medium consists of a multiple layer of sand with a variety in size and specific gravity. Sand filters can be supplied in different sizes and materials, both hand operated and fully automatically.

siemens    →   simens

Siemens (S) is the SI derived unit of of electrical conductance of a conductor in which a current of one ampere is produced by an electrical potential difference of one volt (S = A·V^-1 = Ω^-1). The unit was named after the German scientist Ernst Werner von Siemens (1816-1892).

ferrite    →   ferit

Ferrites are ceramic materials of the nominal formula MO·Fe₂O₃, where M is a divalent metal (Co, Mn, NI, or Zn). The ferrites show either ferrimagnetism or ferromagnetism, but are not electrical conductors, and they are used in high-frequency circuits as magnetic cores, in rectifiers on memory and record tapes, and various related uses in radio, television, radar, computers, and automatic control systems.

Fischer-Tropsch process    →   Fischer-Tropschov postupak

Fischer-Tropsch process is an industrial method of making hydrocarbon fuels from carbon monoxide and hydrogen. The process was introduced in 1933. and used by Germany in World War II. to produce motor fuel. Hydrogen and carbon monoxide are mixed in the ratio 2:1 (water gas was used with added hydrogen) and passed at 200 °C over a nickel or cobalt catalyst. The resulting hydrocarbon mixture can be separated into a higher-boiling fraction for Diesel engines and a lower-boiling petrol fraction. The petrol fraction contains a high proportion of straight-chain hydrocarbons and has to be reformed for use in motor fuel. Alcohols, aldehydes, and ketones are also present. The process is also used in the manufacture of SNG from coal. It is named after the German chemist Franz Fischer (1852-1932) and the Czech Hans Tropsch (1839-1935).

flammable limit    →   granica zapaljivosti

Flammable limits refer to the conditions under which a mixture of a flammable material and air may catch fire or explode. When vapour s of a flammable or combustible liquid are mixed with air in the proper proportions in the presence of a source of ignition, rapid combustion or an explosion can occur. The proper proportion is called the flammable range and is also often referred to as the explosive range. The flammable range includes all concentrations of flammable vapour or gas in air, in which a flash will occur or a flame will travel if the mixture is ignited.

The lower flammable limit (LEL) or the lower explosive limit is the lowest concentration of a flammable vapour or gas in air that will propagate a flame from an ignition source. The upper flammable limit (UEL) or the upper explosive limit is the highest concentration of a flammable vapour or gas in air that will propagate a flame from an ignition source. Any concentration between these limits can ignite or explode.

fossil fuel    →   fosilno gorivo

Fossil fuels (coal, oil, and natural gas) are the fuels used by man as a source of energy. They are formed from the remains of living organisms and all have a high carbon or hydrogen content. They have value as fuels on the exothermic oxidation of carbon to form carbon dioxide

and the oxidation of hydrogen to form water

solvation    →   solvatacija

Solvation is the process by which solvent molecules surround and interact with solute ions or molecules.

solvent    →   otapalo

Solvent is a component of a solution which is found in a greater quantity than all other components. Solvent is a plain liquid can also be a mixture. Water is usually used as a solvent.