March/April 2011

Automation by the Numbers


The U.S. Environmental Protection Agency (EPA) recently gave a green light to an alternative automotive air conditioning refrigerant, hydrofluoroolefin-1234yf (HFO 1234yf). The compound in current widespread use, hydrofluorocarbon134a (HFC-134a), has a much higher global warming potential, the agency said. Using a refrigerant with less global warming potential than HFC-134a is a cost-effective way for automakers to meet greenhouse gas emission standards for cars and light trucks that will take effect with model year 2012, EPA said. The chemical meets a European Union regulation that bans the use of HFC-134a starting this year and allows only refrigerants with a global warming potential of less than 150. HFO-1234yf was developed jointly by DuPont and Honeywell in response to the EU regulation.


Guojun Liu, a chemistry professor and an expert in polymer synthesis, has discovered a way to use nanotechnology to reduce friction in automobile engines and machines, according to ScienceDaily. Liu's team prepared miniscule polymer particles that were only tens of nanometers in size. These particles were then dispersed in automobile engine base oils. When tested under metal surface contact conditions that simulated conditions found in automobile engines, these tiny particles were discovered to have an unprecedented friction reduction capability. Even at a low concentration, the nanoparticles performed much better than the friction additive that is currently used by many industries. They were able to reduce friction by 55% more than the currently achievable rate.


The National Institute of Standards and Technology (NIST) announced it stopped calibrating mercury thermometers starting March 1-a move that brings the U.S. one step closer to phasing out these temperature-measuring devices for good. Although mercury thermometers have been mostly phased out of daily home use, the tool, which was invented in the 1700s by Gabriel Daniel Fahrenheit, remains a standard measuring device for many industries, including regulating the temperature of a chemical concoction being made in an industrial lab, and monitoring the temperature in blood banks and vaccine storage facilities. The alternative to the mercury thermometer is the digital thermometer, which measures temperature by monitoring changes in electrical properties (voltage and resistance) of metals inside the device. While mercury thermometers can measure temperature within one degree Celsius, digital thermometers can be as accurate as 0.001 degrees C-a difference of four orders of magnitude in accuracy.


The Pentagon has ordered a test batch of long-range electroshock projectiles-call them "Taser grenades"-which will be designed to be fired from military grenade launchers. According to New Scientist, the 40-millimetre Human Electro-Muscular Incapacitation (HEMI) projectile developed by Taser International is a self-contained unit that sticks to the target and incapacitates them with a series of intense electric shocks. This "wireless" approach gives it a range of 100 meters, several times further than earlier devices, which fire darts trailing wires connected to the firing unit. The period of incapacitation is currently set to 30 seconds, much higher than other tasers that only shock for 5 seconds. However, the shock duration of the HEMI round can be extended upwards to several minutes. The U.S. Marine Corps is also evaluating the HEMI.