Gasoline also known as petrol outside North America, is a transparent, petroleum-derived liquid that is used primarily as a fuel in internal combustion engines. It consists mostly of organic compounds obtained by the fractional distillation of petroleum, enhanced with a variety of additives.
On average, a 42-gallon barrel of crude oil (159 L) yields about 19 US gallons (72 L) of gasoline when processed in an oil refinery, though this can and does vary based on the crude oil source's assay.
The characteristic of a particular gasoline blend to resist igniting too early (which causes knocking and reduces efficiency in reciprocating engines) is measured by its octane rating. Gasoline is produced in several grades of octane rating. Tetraethyllead and other lead compounds are no longer used in most areas to regulate and increase octane-rating, but many other additives are put into gasoline to improve its chemical stability, control corrosiveness and provide fuel system 'cleaning,' and determine performance characteristics under intended use. Sometimes, gasoline also contains ethanol as an alternative fuel, for economic or environmental reasons.
potential lubricating properties
On September 6, 1866 American John Ellis founded the Continuous Oil Refining Company (Later to become Valvoline). While studying the possible healing powers of crude oil, Dr. Ellis was disappointed to find no real medicinal value, but was intrigued by its potential lubricating properties. He eventually abandoned the medical practice to devote his time to the development of an all-petroleum, high viscosity lubricant for steam engines ? then using inefficient combinations of petroleum and animal and vegetable fats. He made his breakthrough when he developed an oil that worked effectively in high temperatures. This meant no more gummed valves, corroded cylinders or leaking seals. In 1873 Ellis officially renamed the company to Valvoline after the steam engine valves the product lubricated.
Approved for urban bus
City bus can be approved for use by the city after a thorough check its technical condition, it must be not only efficient, but also to meet all the standards required for vehicles to carry passengers on the urban areas. The most important will always be the safety and comfort of passengers, for which you need to take care of before a vehicle is moving, and in the course of passenger transport. Repairing city bus it will be made after finding in it the existence of any defects that might jeopardize the safety of passengers. On the other hand, making such activities as engine oil or brake, may belong to the same driver or service personnel.