INTERCONNECTS

MOUNTAIN VIEW, Calif. -- Cleaner-burning gasoline, whose many benefits include less acid rain and optimized catalytic converter operation, is but one of many beneficial applications of work that chemist Yosslen Aray, Ph.D., conducts in Venezuela in labs equipped with SGI(R) (NYSE:SGI) systems. The internationally recognized materials expert is the recent recipient of the prestigious Lorenzo Mendoza Fleury award, a Venezuelan honor recognizing the greatest national achievements in chemistry, mathematics, medicine, biology and physics. Bestowed once every two years since Venezuela's Fundacion Polar, dedicated to science literacy, began the tradition 25 years ago, the Fleury award is a closely watched honor, especially in Latin America. Since winning the award along with four peers in the late spring, Aray has been interviewed by newspapers, magazines and radio and TV stations across the continent. Aray specializes in computational chemistry, particularly analysis of electronic density to determine chemical properties at the molecular level. Nanotechnology -- the development of tiny microscopic devices -- is one pioneering application area, but another key application is far less esoteric: reducing the sulphur content of processed gasoline, which, among other benefits, enables automobile catalytic converters to operate more efficiently. Sulphur is highly reactive with the precious metals used on the active surface of catalysts, which limits the efficiency of the devices by clogging up the catalyst surface with sulphur. The less sulphur in gasoline, the more catalytic converter space is available to trap other pollutants, resulting in optimized catalyst performance. "All vehicles equipped with catalytic converters benefit from low-sulphur fuel," explains Aray, who resides in Caracas, Venezuela. "It's exciting to work on a chemistry challenge whose real-world application can have such a dramatic impact on the lives of people everywhere." Reducing sulphur levels in gasoline also helps in two ways in the fight against acid rain, which damages forests and other ecosystems. First, poorly operating catalytic converters tend to increase levels of nitrogen oxide emissions from gas-powered cars, which contribute to acidification. Second, sulphur trapped by catalytic converters eventually burns, releasing sulphur dioxide, which enters the atmosphere. When it comes in contact with water and sunlight, sulphur dioxide turns into acid rain. Sulphur is even more prevalent in diesel fuels and is a source of particulate emissions. Such fine particulate matter is widely accepted to be the cause of a range of respiratory and heart problems. In his Venezuelan lab, Aray works specifically on improving a refinery process known as hydrosulfurization, through which sulfur is removed from petroleum streams by treating it with hydrogen to form hydrogen sulfide, which can be stripped from the oil as a gas. His research projects are conducted at two labs containing SGI equipment: -- His government-funded group lab at the Venezuelan Institute of Scientific Research, where the award-winning chemist earned his doctoral degree in 1991 and where he now holds the title of associate investigator. SGI equipment here includes an SGI(R) Origin(R) server and Silicon Graphics(R) Onyx(R) visualization system, Silicon Graphics(R) O2(R) and Silicon Graphics(R) Octane(R) visual workstations. -- The U.S. National Institute of Standards and Technologies (NIST) in Maryland, where Aray is a guest researcher working on modeling of molecular electronics for nanotechnology devices. The Physical and Chemical Properties Division uses a dedicated SGI(R) Origin(R) 300 server and Silicon Graphics Fuel(TM) visualization workstation and also routinely utilizes a shared-resource NIST SGI Origin supercomputer. "Our group designs materials with specific properties determined by their electronic density. SGI visualization technologies convert large electronic density data sets into very high-resolution images. In other words, SGI computers let us see everything," says Aray. Referring to work done in his Venezuelan lab, he explains, "I opened the lab in 1996 using SGI technologies on the advice of peers around the world who advised us to create an SGI infrastructure for both computation and simulation. It's been an excellent experience with world-class results." Other Fleury award winners this year were Socrates Acevedo (chemistry), Jesus Gonzalez (physics), Jose R. Lopez Padrino (medicine) and Lazaro Recht (mathematics). They were chosen from a field of 47 nominees on the basis of the originality, creativity and impact on the international science community of their research. Each received an honorarium of approximately $10,000. "SGI extends its congratulations to Dr. Aray for this honor," says Bill Bartling, director, global energy solutions. "It's gratifying to know that SGI technologies have played such a pivotal role in his widely hailed research." For further details about SGI's involvement with research labs and universities around the world, visit www.sgi.com/go/research.