ChemWeb Newsletter

Not a subscriber? Join now.March 14, 2006


ChemWeb's Alchemist gets cracking with an alternative approach to gasoline production from The Netherlands, finds out how to protect fashion-conscious athletes from impact injuries, checks out the soft core particle scene, and discovers a possible mechanism for how diabetes drugs work. Finally, this week, we hear that French researchers have carried out the first experiments to measure how heat flow behaves far from a heated surface, which could help us understand air conditioning units and the interiors of stars!

Xander Dupain of the Technical University of Delft in The Netherlands and his colleagues have devised a method for producing cleaner vehicle fuels. The approach could allow oil companies to use even heavier and "dirtier" crude oil as supplies of high-quality crude begins to dwindle. By combining conventional catalytic cracking with the Fischer-Tropsch synthesis process, Dupain reckons this method would be cheaper than hydrocracking and would allow the fairly heavy fraction containing waxes to be used to produce gasoline and diesel.

Protection from impact injuries is not the first thing that springs to mind when one considered textiles that are comfortable, flexible and breathable. However, UK company d3o has worked with a sports clothing manufacturer to develop a range of protective gear that has all these properties plus one very special property. d3o's "Mesh" is a perforated textured sheet that can be fashioned into any kind of garment, but crucially has a molecular structure that changes on impact. A blow to the material causes its molecules to temporary cross links with each other, almost instantly stiffening the material and crucially absorbing the energy of the impact. Once the force is removed, Mesh returns to its native state. Soccer players' shin-pads are the obvious first application, but any sport in which impact injuries are common could benefit by providing athletes with protective "padding" that doesn't hinder their movements nor rely on bulky and unsightly padding.

Danish and German researchers have developed a new type of particle with a hard shell and a soft core that changes depending on its temperature. Walter Richtering and Ingo Berndt of the University of Aachen, Germany, and Jan Skov Pedersen of the University of Århus, Denmark, have synthesized polymeric microspheres with a core made of poly-N-isopropylacrylamide and a shell of poly-N-isopropylmethacrylamide. The microspheres are densely packed at 70 Celsius, the temperature at which they are prepared, when they are cooled to room temperature (approx 25 Celsius, however, the core and shell have the highest water content and the lowest density and dissolved molecules can pass through the shell into the core, where they disperse. At body temperature (approx 39 Celsius), only the swelling properties of the shell are changed, which expels water, shrinks and becomes denser than the core. Substances dissolved in the core can no longer pass through the shell and are thus locked inside.

New insights into the mode of action thiazolidinediones (TZDs) class of oral pharmaceuticals for type 2 diabetes are revealed this month in the journal Diabetes. Allison Goldfine and colleagues at the Joslin Diabetes Center in Boston examined muscle and fat tissue from patients with type 2 diabetes before and after they took the TZD drug rosiglitazone. The researchers found that levels of two proteins, Necdin and E2F4, which are important in regulating cell replication, were altered in muscle and fat after two months. “Because the proteins are important in regulating the cell cycle, the findings suggest that TZDs may work, in part, by altering the cell differentiation state, or level of cell maturity. Additionally, the two proteins Necdin and E2F4 may represent new drug targets that may be useful in the future for treatment of patients with diabetes, says Goldfine.

French researchers have carried out the first experiments to measure how heat flow behaves far from a heated surface. They used a carefully arranged set of thermometers in a cell of heated water to track the convection currents and to determined the size of the "blobs" of warm water that transfer heat. Mathieu Gibert and his colleagues at the Ecole Normale Supérieure in Lyon have also proposed a method of determining heat flow in less controlled situations, such as the atmosphere. The results could help researchers better understand convection high in the atmosphere, around high-speed computer chips, air-conditioning systems, and even the insides of stars. Arranging the thermometers in this latter example could be rather problematic, however.