The importance of gasoline was not recognized in the 19th century, when it was used in a great deal of kerosene. The oil refining then relied on simple distillation processes to separate the different components of the oil from the boiling point. The boiling point of the kerosene component is higher, and the use of safety when lighting lamps becomes the main product of crude oil refining, while gasoline and other components are often burned as fuel. By the mid - to late 19th century, the successful use of gasoline engines in 1886, in 1886, the gasoline engine was successfully used as a driving force, thus the importance of gasoline increased. But using distillation, only 20% of the gasoline can be extracted from crude oil. In 1911, the standard oil company have solved the problem of low gasoline yield, by William burton and Robert hamm forest thermal cracking process of the invention, the heavy quality heating gas oil cracking of light gasoline fractions, such as to overall improve the gasoline yield, thermal cracking process in 1913 won the patent license in the United States. The subsequent catalytic cracking process has further improved the gasoline yield and octane value. In terms of the purchase of intermediate products in the market, because a lot of manufacturers are generally buy goods from a handful of suppliers, it is beneficial to this a few suppliers to achieve economies of scale and reduce the cost of production. Moreover, market competition pressure between intermediate product suppliers forces suppliers to reduce production costs. In addition, when a few suppliers in the face of many intermediate products of demanders, these a few suppliers can be avoided due to the limited market demand caused by unstable, the loss that may lead to maintain a stable overall sales. From the end of the 19th century to the early 20th century, car designers focused their energies on the development and innovation of mechanical engineering. First half of the 20th century, all about the basic structure of the car has been invented, automotive designers begin from the outside to improve on modelling, and successively introduced the aerodynamics, fluid mechanics, human body engineering and industrial modelling design (industrial aesthetics), etc It said the regulations allow agency staff to forgo their right to equal pay with directly employed staff in return for a contract that offers pay between assignments, known as a “Swedish derogation” contract. It said these were “widely abused, as noted by the government commissioned Taylor Review of Modern Working Practises”. Workers in the category for caring, leisure and other service occupations earn £218 more on average than equivalent full-time members of staff, while temporary managers and directors enjoy a £2,477 pay boost compared to full-timers. At present, there are 89, 92, 95 and other labels on the market, which represent the octane value of gasoline, which means the anti-detonation of gasoline, which has nothing to do with the cleaning of gasoline. The so-called "high label gasoline is cleaner" is misleading. It is more scientific, more economical, and can give full play to the engine's efficiency according to the engine compression ratio or the requirement of the automobile instruction manual.