Stories tagged black ice

Jan
19
2010

dragster: Ok, so the nanodragster does not look quite like this...
dragster: Ok, so the nanodragster does not look quite like this...Courtesy creative.paradox
Ladies and Gentlemen, start your engines! Well, technically, nanocars do not have engines. Instead of an engine, they move along a super thin, superfine layer of gold when heated up. The original design by a team at Rice University used four buckyballs as the wheels. They were really great at staying on the gold layer, but needed pretty high temperatures (around 400 degrees Fahrenheit) to get moving. Another design used smaller wheels made of p-carborane. However, this compound slides around the gold layer as if the gold was black ice. It was also difficult to take pictures of the slipping and sliding p-carborane dragster. Naturally, the answer is to have the two rear wheels made of buckyballs, and the front wheels made of the p-carborane compound, resulting in a nanodragster! The new design has a good balance of grip and agility. Plus, a lower temperature is required to get it to move. The nanodragster blazes along the gold layer at speeds of up to 0.014 millimeters per hour! Yes, millimeters per hour! Keep in mind that the nanodragster itself is over 50,000 times thinner than a human hair. The Rice team hopes that structures like the nanodragster will find uses in future nanotechnologies perhaps dealing with electronics.

Dec
16
2008

Glass tree road: A road in Hendersonville North Carolina following an ice storm.
Glass tree road: A road in Hendersonville North Carolina following an ice storm.Courtesy vgm8383
Its really cold where I live these days. It was 23 below zero Celsius (this is a science blog) this morning when I woke up. Bitter cold. An interesting phenomenon happens on roads when it gets this cold, a condition called black ice. It was in full effect this morning, with Twin City roads having over a dozen accidents and causing lengthy commute delays.

So, what is black ice (besides an AC/DC album)?

Black ice is a type of ice that is usually thin and forms without bubbles inside, making it harder to see. Because of its transparency, it usually takes on the color of whatever it is on, making it doubly hard to see and a hazard to drivers, bikers and walkers.

Black ice on roads is most common at night or in the early morning when temperatures are at their lowest, and before the sun has had a chance to warm the road surface. It can be mixed in with a wet road, and it can be hard to tell the difference between a road that is wet and a road that has black ice. Black ice can form more easily on bridges and overpasses as the very cold air can cool both the top and the bottom of the road at the same time, causing it to cool below freezing more quickly. Black ice can form from any source of moisture – light rain, meting and re-freezing snow or any other source of moisture on a road surface.

Here are some tips for driving on black ice. Drive safe my fellow Minnesotans – I’m going to be on the road with you this evening!