Stories tagged chemistry

Researchers in France have invented a new type of rubber that repairs itself. Press two pieces together, and they bond together without using any kind of glue or heat.

Jun
25
2007

Nipping crime in the bud: When asked whether or not this method could be used to find the source of other illegal drugs, the Alaskan scientist stated, "Um... What?"  (photo by ilmungo)
Nipping crime in the bud: When asked whether or not this method could be used to find the source of other illegal drugs, the Alaskan scientist stated, "Um... What?"
(photo by ilmungo)

Sometimes I place quotation “marks” randomly. It’s a kind of written-language Tourette’s Syndrome, and I live in constant fear that its effects might “lead” people to false conclusions. “”

Anyhow, scientists at the University of Alaska Fairbanks are developing methods of tracing samples of marijuana back to their points of origin by studying the “isotopic fingerprint” of the plants. Presumably this is to aid people suffering from the advanced stages glaucoma find their medicine.

Whatever the reason for it might be, the process for determining the growing location of the drug is an interesting one. Isotopes, for those of you who are still reading, are, of course, elements with the same number of protons and electrons, but different numbers of neutrons. For example, the element nitrogen can be found with 13 neutrons, 14 neutrons, or 15 neutrons – those are all isotopes of nitrogen.

When you look at the ratio of isotopes in an object, you can sometimes find out where that object came from geographically, because certain areas will sometimes have isotopic signatures. This is how scientists figured out where Otzi the Iceman came from: the enamel on his teeth had an isotopic match with a small region in Italy, so it’s very likely he grew up there.

Applying this basic method to marijuana, the Alaskan scientists are finding that isotopic levels of hydrogen and oxygen in the plants can show where the water they were fed with came from. Carbon in the plant can show whether or not it was grown indoors. Nitrogen isotope levels can also be used to learn about plants’ origins. Combining the information from all of these ratios, researchers are attempting to construct a map of marijuana isotopic signatures, so that any sample with unknown origins could be matched up with a specific location.

In order to achieve this isotope map, however, the project director says he needs “time, money and many more samples of marijuana.”

Science takes back the streets!

May
25
2007

Plastic is a ball: Look how far plastic technology has come. We wouldn't have these cool balls without its invention 100 years ago. (Photo by Liethwalker)
Plastic is a ball: Look how far plastic technology has come. We wouldn't have these cool balls without its invention 100 years ago. (Photo by Liethwalker)
Benjamin Braddock, Dustin Hoffman’s character in the film “The Graduate,” should have listened to that sage piece of advice…that the wave of the future was plastics.

It’s proven to be quite a resilient substance. This year marks 100th anniversary of the creation of the plastic. Can you think of a day in your life that plastic hasn’t played some important part of?

Inventor of the process of making plastic – Leo Baekeland – created the process of developing phenol-formaldehyde polymer resin in 1907. The new material found new uses over the quickly as rayon, cellophane, PVC and polyethylene, to name just a few.

Sticking around: New and new uses are being found for plastic, even in its 100th year. These hay bales in Ireland are wrapped in plastic to keep the moisture out. (Photo by bigeoino)
Sticking around: New and new uses are being found for plastic, even in its 100th year. These hay bales in Ireland are wrapped in plastic to keep the moisture out. (Photo by bigeoino)
And it’s probably going to be around for a while longer. New coming uses for plastic, things that are still in the development stages, include plastic hemoglobin-like material that can be used in human blood and airplane parts that can change shape depending on the weather and air conditions that a plane is flying through.

With all that development, however, there are still some big challenges. Only about 10 percent of all plastic is recycled, which means a growing supply of plastic wastes that have to be dealt with in a reasonable fashion.

So if you’re looking for a reason to have a party, why not celebrate plastic’s 100th birthday!

Percy Julian
Percy Julian
PBS will air a documentary tomorrow night on Percy Julian an important scientist you may never have heard of before :

"Born the grandson of Alabama slaves during segregation in 1899 and facing a lifetime of personal and professional challenges, Percy Lavon Julian nevertheless went on to become one of the 20th century's most influential scientists."

French engineer and chemist Georges Claude died on May 23, 1960. In 1902, he invented the neon light (obviously near and dear to our hearts!) by applying electricity to a sealed tube of neon gas. Used to promote a Packard car dealership in Los Angeles, the first neon signs in the US cost $24,000.