Dryopteris

Petroleum (crude oil) is a naturally occurring liquid fossil fuel found in rock formations in the Earth, consisting of a complex mixture of hydrocarbons of various lengths. Due to its high energy density, easy transportability and relative abundance, petroleum has become the world's most important source of energy since the mid 1950s. Most petroleum is used for producing gasoline (petrol) and fuel oil, both important primary energy sources. Petroleum is also the raw material for many chemical products.

Most petroleum is extracted from oil wells found in oil fields. Although it is also possible to extract petroleum from oil shale or tar sands, both of which are known to exist in large quantities, doing so at low cost and without impacting the environment remains a challenge. The first modern oil well was drilled in 1848 in Azerbaijan, but it was the introduction of the internal combustion engine in the early 20th century that provided the demand that has largely sustained the industry to this day. The top three oil producing countries are Saudi Arabia, Russia, and the United States.

Burning oil releases carbon dioxide into the atmosphere, one of the major greenhouse gases contributing to global warming. Bioethanol and biodiesel are already used to some extent as alternatives, notably in Brazil, as are hybrid electric vehicles. Trials using hydrogen fuel are also in progress. There are further concerns about security of supply, oil price rises and whether world oil production may reach a peak, before declining, as predicted by Hubbert peak theory.

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• According to research by the IPCC, government funding for most energy research programmes has been flat or declining for nearly 20 years, and is now about half the 1980 level?

• Renewable energy in Iceland provides over 70% of the country's primary energy needs, and 99.9% of Iceland's electricity?

• The Rance tidal power plant in France was the world's 1st electrical generating station powered by tidal energy?

• A tropical cyclone (example pictured) can release heat energy at the rate of 50 to 200 trillion joules per day, roughly 200 times the world-wide electrical generating capacity?

• Ordinary fossil fuel power plants convert between 36% and 48% of the fuel's energy into electricity, with the remainder being lost as waste heat, about half of which is unavoidable due to the second law of thermodynamics?

• Burning biomass indoors leads to between 1.5 and 2 million deaths each year from indoor air pollution in developing nations?

• Over 50% of world small hydroelectricity generating capacity is in China?

• Charles Fritts developed the first solar cell in 1884, although its efficiency was less than 1%?

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Enrico Fermi (September 29, 1901 – November 28, 1954) was an Italian physicist most noted for his work on the development of the first nuclear reactor, and for the development of quantum theory. Fermi won the 1938 Nobel Prize in Physics for his work on induced radioactivity.

Fermi was well-known for his simplicity in solving problems. Whenever possible, he avoided complicated mathematics and obtained quick results based on order of magnitude estimates. Fermi also meticulously recorded his calculations in notebooks, and later used to solve many new problems that he encountered based on these earlier known problems.

After accepting the 1938 Nobel Prize in Stockholm, Fermi immigrated to New York with his family to escape the anti-Semitic laws of Fascist Italy, as his wife Laura was Jewish.

After working at Columbia University, Fermi went to the University of Chicago and began studies that led to the construction of the world's first nuclear reactor Chicago Pile-1 (CP-1). The first artificial, self-sustaining, nuclear chain reaction was initiated within CP-1, on December 2, 1942.

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