Energy content of biofuel (J/kg) or equivalent units. Energy density is the amount of energy stored in a fuel per unit volume, expressed in SI units as joule per litre (J/L) or equivalent units. The table below includes entries for popular substances already used for their energy, or being discussed for such use. The second column shows specific energy, the energy content in megajoules per unit of mass in kilograms, useful in understanding the energy that can be extracted from the fuel. The third column in the table lists energy density, the energy content per liter of volume, which is useful for understanding the
Work unit in China led to further difficulties for the "danwei" system as the state run enterprises were increasingly unable to compete. At the same time the role of the work unit has changed as China has moved from a socialist ideology to "Socialism with Chinese characteristics". By 2000 much of the work unit's power had been removed. In 2003, for example, it became possible to marry or divorce someone without needing authorization from one's work unit. Work unit A unit or danwei () is the name given to a place of employment in the People's Republic of China. While the term