Brazil has one of the largest renewable energy programs in the world, involving production of ethanol fuel from sugar cane, and ethanol now provides 18 percent of the country's automotive fuel. As a result, Brazil, which years ago had to import a large share of the petroleum needed for domestic consumption, recently reached complete self-sufficiency in oil.
Most cars on the road today in the U.S. can run on blends of up to 10% ethanol, and motor vehicle manufacturers already produce vehicles designed to run on much higher ethanol blends. Ford, DaimlerChrysler, and General Motors Corporation are among the automobile companies that sell “flexible-fuel” cars, trucks, and minivans that can use gasoline and ethanol blends ranging from pure gasoline up to 85% ethanol (E85). By mid-2006, there were approximately six million E85-compatible vehicles on U.S. roads.
Aral Sea
The Aral Sea ( (Aral Tengizi), , ) is a lake in Central Asia. It is between Kazakhstan in the north and Karakalpakstan, an autonomous region of Uzbekistan, in the south.
Since the 1960s, the Aral Sea shrank. 90% of the sea has gone. The rivers that fed it (the Amu Darya and the Syr Darya) were used by the Soviet Union for irrigating cotton production. What is left of the Aral Sea is heavily polluted, largely as the result of weapons testing, industrial projects, and fertilizer runoff before and after the breakup of the Soviet Union.
There is a project to save at least the northern part of the Aral Sea. For this, a dam was built in the 1990 to stop water running off. Climate improved in the following years, and water levels rose again. However, that dam broke, and was rebuilt in 2005, with international funding.
Another problem was that the Island of Rebirth had been used for the testing of biological weapons until 1993. It is currently contaminated with anthrax, the plague, and tularemia. Since 2001, it is no longer an island, but a peninsula.
Radiation
In physics, radiation is the emission or transmission of energy in the form of waves or particles through space or through a material medium.
This includes:
Radiation may also refer to the energy, waves, or particles being radiated. Originally, radiation waves do not contain particles as they are transferred to Earth by the Sun for example.
Many people are already familiar with electromagnetic radiation (EMR), including light. The electromagnetic spectrum shows the types of radiation according to their wavelength and frequency. Some kinds are:
Ionizing radiation is radiation that carries enough energy to free electrons from atoms or molecules.
Only certain types of radiation are harmful to humans. For example, ultraviolet radiation can give people sunburns. X-rays and gamma rays can make a person sick, or even die, depending on the dose they get. Some types of particle radiation can also make people sick and lead to burns. If radiation does not carry high enough levels of energy, though, then these changes will not happen when something is hit by the radiation. This is referred to as non-ionizing radiation, which is not as dangerous.
One can distinguish between various types of radiation by looking at the source of the radiation, its wavelength (if the radiation is electromagnetic), the amount of energy being carried, any particles involved, etc. Radioactive material is a material which emits radiation. Uranium and plutonium are examples of radioactive materials. The atoms they are made of tend to fall apart and give off different kinds of radiation, like gamma rays and lots of particle radiation.
Ionizing radiation can kill living things. It can cause genetic mutations, as shown by H.J. Muller. It can destroy cells in the body which divide, and thus indirectly kill a person.
Non-ionizing radiation
Non-ionizing radiation (or, esp. in British English, non-ionising radiation) means any type of electromagnetic radiation that does not carry enough energy to ionize atoms or molecules - that is, completely remove an electron from an atom or molecule.
The composition of this radiation can vary depending on what may be ionized. Visible light, near ultraviolet, infrared, microwave and radio waves are all examples of non-ionizing radiation, though visible and near ultraviolet can also ionize some molecules. The light from the Sun that reaches the earth is largely composed of non-ionizing radiation, with the notable exception of some ultraviolet rays. However, most ionizing radiation is filtered out by the atmosphere.
Electromagnetic spectrum
The electromagnetic (EM) spectrum is the range of all possible electromagnetic radiation. Electromagnetic radiation can be divided into octaves — as sound waves are — adding up to eighty-one octaves. Physicists have studied electromagnetic radiation with wavelengths from thousands of kilometres down to fractions of the size of an atom. It is commonly said that EM waves beyond these limits are uncommon, although this is not known to be true. The short wavelength limit is likely to be the Planck length, and the long-wavelength limit is the size of the universe itself, though in principle the spectrum is infinite.
Radiation of shorter wavelength than about 30 μm is commonly detected by its ability to exceed the ionization energy of atoms. Radiation of longer than 3mm is commonly detected by its ability to induce electrical currents. Radiation between these limits was little used until the 21st century because of the difficulty of detecting it.
Nearly all objects in the universe emit, reflect or transmit some light. (Black holes do not.) The distribution of this light along the electromagnetic spectrum (called the "spectrum" of the object) is determined by what the object is made of. Several types of spectra can be distinguished depending upon the nature of the radiation coming from an object.
Spectroscopy is the branch of physics that observes matter by its emitted or reflected spectra.
Spectrum (disambiguation)
A spectrum is a condition or value that is not limited to a specific set of values but can vary infinitely within a continuum.
Spectrum may refer more specifically to:
Continuum
A Continuum is a continuous series where all parts are very similar to their nearest neighbour, but the ends or extremes of it are different from each other.
This describes something that changes gradually (little by little) from one condition, to a different condition, but without any sudden changes or discontinuities.
The difference between a continuum, and something with very different changes that can be measured, is important for all continuum theories.
Continuum may also refer to:
Revenge (album)
Revenge is a studio album by the American hard rock/heavy metal band Kiss. It was released on May 14, 1992.
Continuum (theory)
A continuum is when a change happens over time or an area without being interrupted.
Space-time is when space and time are said to be part of the same continuum instead of two different continuums.
A dialect continuum is a group of language dialects that change over an area. In a dialect continuum, two dialects are more different when they are farther away from each other.
Joseph Goebbels
He was a close friend of Adolf Hitler. Goebbels stayed with Hitler in the Führerbunker until Hitler's suicide on 30 April 1945. After Hitler's death, Goebbels was chancellor of Germany for one day, before he and his wife Magda Goebbels killed themselves. Just before she died, Magda killed their six children with poison.