In addition to the backscatter machines, the TSA has also deployed about 260 millimeter-wave machines which use radio waves and do not emit X-rays.
Many fossil fuel stocks have been profitable in recent years, but because neither the producers nor consumers pay to emit climate-warming carbon pollution into the atmosphere, those profits are grossly distorted.
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The other, which faces a specialised type of solar cell made of a material called indium gallium arsenide, is sculpted into a structure called a photonic crystal that causes it to emit infra-red radiation selectively at the frequency best absorbed by the cell.
Light-emitting diodes--semiconductors that emit light when electricity passes through them--have been around since the 1960s.
The blocks absorb CO2 when they are cool and re-emit it when they are hot.
Instead of auctioning permits to emit, Waxman-Markey gives 85% of them away, at least at first.
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They emit fewer well-to-wheel greenhouse gas emissions than virtually any other vehicle other than bikes and skateboards.
The ETS, as the EU carbon market is known, was designed to encourage companies to invest in technologies that reduce their emissions in the long term, rather than to simply buy more permits to emit more carbon-dioxide.
To stick to the current agreed global limit on emissions - which is sure to be breached - the firms would probably be able to emit no more than about 125-275 billion tonnes of CO2 - about a quarter of their assets.
Active galaxies emit jets of light - up to trillions of times more energetic than the light we see - and a blazar is one with a jet pointing toward the Earth.
Current Blu-ray lasers emit light in the blue part of the electromagnetic spectrum (about 405 nm wavelength).
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It was also a big week for lighting news as we learned that compact fluorescent light bulbs emit potentially harmful UV radiation -- another good reason to make the switch to LEDs.
And electrically powered trains would emit less nasty carbon than fossil-fuelled aircraft.
Never store your clothes over long periods in plastic dry-cleaning bags which emit gases that can stain or yellow fabrics as well as break down the elasticity in stretch garments.
Properly seasoned cast iron will provide much the same results but without leaching out the perfluorochemicals non-stick surfaces are made from or the toxic fumes that studies have shown hot non-stick cookware can emit.
Natural gas vehicles emit up to 90 percent fewer ozone-depleting gases than gasoline-powered cars.
Each allowance represents the right to emit one ton of CO2 or CO2-equivalent GHG.
It will allow gas-fired power stations to emit the same amount of carbon dioxide as they do now until 2045.
Most of the demand growth will come from natural gas-fired power plants, which emit 60% less carbon than coal burners.
The change also will likely squelch pilot complaints about going through full-body scanners, some of which emit low levels of radiation.
The company says that they emit 20% less carbon dioxide than a gasoline-fueled engine with a catalytic converter and consume 20% less fuel.
Here's the problem: According to the Clean Air Act, once the EPA regulates greenhouse gas emissions for autos, it must do so for so-called "stationary sources" that emit the equivalent of more than 250 tons of CO2 per year.
On average (depending on the type of coal used) 1 kWh produces 1.4 pounds of CO2 which would mean a 25-mile journey using 5 kWh would emit around 7 pounds of CO2 compared to your average vehicles emitting 22 pounds of C02.
In the rich world, Europe already caps carbon-dioxide emissions, and trades permission to emit the gas.
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Natural-gas plants are cheaper than renewables but emit greenhouse gases, which nuclear power plants do not.
Even something too small to emit visible light will probably give off radio waves and infra-red radiation (Jupiter does).
The instruments aboard the satellite allowed scientists to spot close-in asteroids by picking up the heat they emit, Mainzer said.
Researchers looked at 62 patients with implantable cardioverter-defibrillators, devices that monitor heart rhythms and emit painful shocks in response to dangerous rhythms.
Since power plants that burn natural gas emit about half the amount of the greenhouse gases as coal-fired power, some say that the gas drilling boom has helped the U.S. become the only major industrialized country to significantly reduce greenhouse emissions.
Mr. BASKIND: We're talking about coal-fired power plants a lot right now because they emit a lot of carbon dioxide.
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