Fuel Saving, Harmful Emissions and Super Magnets

Saving Fuel
Since the development of the internal combustion engine, people have looked for ways to increase its efficiency, in order to increase the fuel economy of the automobile.
Although many technologies have had a beneficial effect on vehicles' fuel economies, claims as to the efficacy of some devices have clearly been bogus or misleading.
An early example of a "fuel saving gadget" sold with claims that were difficult to justify is the 200 mpg carburettor designed by Canadian inventor Charles Nelson Pogue.
A good thing to keep in mind when examining fuel saving devices is that most of these claim major increases in combustion efficiency, something that sounds attractive when you consider the average gasoline engine rarely exceeds 35% efficiency. However, the weak point of the engine is not converting the fuel into heat, but the heat into mechanical energy, hence the reason why many fuel saving devices don't work as claimed. On modern engines there is relatively little scope for improving combustion efficiency. Most of what can be legitimately achieved is done by reducing parasitic losses of accessories e.g. fans, water pump, and pumping losses by taller vehicle gearing.
One reason that ineffective fuel saving gadgets have had some success in the marketplace is that it is surprisingly difficult to measure the fuel economy of a vehicle. This is because of the high level of variance in the fuel economy of a vehicle under normal driving conditions. Consequently, it is extremely difficult to measure small changes to fuel economy.
The large degree of fuel economy variance means that due to psychological factors of selective perception, consumers can be mislead as to the effectiveness of a device.
For this reason, regulatory bodies have developed standardised drive cycles that are useful for statistically significant comparisons of fuel economy.

Air Pollution
Air pollution is the introduction of chemicals, particulate matter, or biological materials that cause harm or discomfort to humans or other living organisms, or damages the natural environment into the atmosphere.
The atmosphere is a complex dynamic natural gaseous system that is essential to support life on planet Earth. Stratospheric ozone depletion due to air pollution has long been recognized as a threat to human health as well as to the Earth's ecosystems.
An air pollutant is known as a substance in the air that can cause harm to humans and the environment. Pollutants can be in the form of solid particles, liquid droplets, or gases. In addition, they may be natural or man-made.
Pollutants can be classified as either primary or secondary. Usually, primary pollutants are substances directly emitted from a process, such as ash from a volcanic eruption, the carbon monoxide gas from a motor vehicle exhaust or sulfur dioxide released from factories.
Secondary pollutants are not emitted directly. Rather, they form in the air when primary pollutants react or interact. An important example of a secondary pollutant is ground level ozone - one of the many secondary pollutants that make up photochemical smog.
Note that some pollutants may be both primary and secondary: that is, they are both emitted directly and formed from other primary pollutants.
About 4 percent of deaths in the United States can be attributed to air pollution, according to the Environmental Science Engineering Program at the Harvard School of Public Health.
Supermagnet/ Neodymium Magnet
A neodymium magnet, a type of rare-earth magnet, is a permanent magnet made from an alloy of neodymium, iron, and boron to form the Nd2Fe14B tetragonal crystalline structure. This material is currently the strongest known type of permanent magnet.
The tetragonal Nd2Fe14B crystal structure has exceptionally high uniaxial magnetocrystalline anisotropy (HA~7 teslas). This gives the compound the potential to have high coercivity (i.e., resistance to being demagnetized). The compound also has a high saturation magnetization (Js ~1.6 T or 16 kG). Therefore, as the maximum energy density is proportional to Js2 this magnetic phase has the potential for storing large amounts of magnetic energy (BHmax ~ 512 kJ/m3 or 64 MG·Oe), considerably more than samarium cobalt (SmCo) magnets, which were the first type of rare earth magnet to be commercialized. In practice, the magnetic properties of neodymium magnets depend on the alloy composition, microstructure, and manufacturing technique employed.