"Let's open up the horizon!" The summons, hurled into the auditorium by chemistry professor and Nobel laureate Richard Ernst, met with an enthusiastic response from the audience of around a hundred researchers and scientists in ETH's "Auditorium Maximum". Not that criticism was wanting in Ernst's lecture. Competition played a more important role than co-operation; more trust was placed in free markets than in regulated trade. In addition "we were too blue-eyed as far as technology was concerned and wanted to forge ahead even more rapidly" – usually without counting the cost, as Ernst admonishes. "This begs the question, 'Are we running in the right direction?' " And "Who will sort out the mess?" Because we were stuck in the middle of an identity crisis that only left room for social issues at the margins. As a scientist he wished for a research culture that did not neglect social and ethical aspects. "Fundamental research is important because we have to go far more deeply into issues. But we also have to include our surroundings," said Ernst. He was of the opinion that scientists had to take on the role of scouts. To carry out this role they must possess high expert qualifications but also bring ethical understanding, creativity and entrepreneurial spirits to their work.

Call for experience in the economy

A similar challenge was issued by Georg Reif, President of the globally active company Alcan Composites, in his address at the first PhD Students' Day of the Department for Mechanical and Process Engineering. "Those who have a thorough understanding of their own discipline as well as a feeling for the economy are successful in the world of business," said Reif, who studied engineering at ETH Zurich. At Alcan serious attention was paid to interdisciplinary collaboration and the fields of ecology and health.

Intersected model of a modern gas turbine: Aurel Stodola paved the way. large

Another main item on the PhD Students' Day programme was the work of the winner of the "ETH Medal 2004". Daniel Häfliger. Häfliger worked with the nanotechnology team at ETH Zurich while he was doing his doctorate thesis, and today he is assistant professor in the Department of Micro and Nanotechnology at the Technical University of Denmark in Lyngby. His lecture described a new method of micro-lithography using thin films of aluminium. "At room temperature and in neutral water, aluminium builds a passive oxide film. If the metal is heated to nearly 100 degrees Celsius by absorbing laser beams, the film dissolves. The metal, thus treated, does not corrode, said Häfliger.

Wide-grip hand: In 1916 Aurel Stodola tried to help people injured in war with this artificial limb. The picture shows Stodola's sketch next to a detail taken from Michelangelo's fresco "Adam" in the Vatican's Sistine Chapel. Picture: D-MAVT/ETHZ

The advantage of this method was that cumbersome procedures were circumvented and that one could do without poisonous chemicals and clean-room facilities. The publication of his work in the renowned journal of Applied Physics A (2002, 74: 115-118) brought the young scientist a lot of attention from specialists in this field.

Particle flow examined

The respective works of Chidambaram Narayanan from the Laboratory of Nuclear Technology and Kai Herrmann from the Laboratory of Aero-thermo Chemistry deal with two different aspects of particle flows. Both labs are attached to the ETH Institute of Energy Technology. Narayanan is primarily interested in the deposits of nanoparticles that occur when air moves. With the help of numerical analysis he has been able to simulate the dynamics of this process. Herrmann examines the flow, flame characterisation and the formation of nitrogen in turbulent, pre-mixed flames. His results are of interest in the planning of gas turbines.

Pioneer of aerosol research

The basis of the work of both scientists is the behaviour of aerosols, minute particles small than 10 micrometers down to a few nanometers. The US citizen Sheldon K. Friedlander (3) is the acknowledged pioneer in the field of aerosol research. This chemical engineer, professor at the Institute of the Environment at the University of California in Los Angeles (UCLA) today, studied at Columbia University and the University of Illinois. He was awarded the ETH "Stodola Medal“ for his work on the science and technology of fine particles in gases. The medal is awarded to scientists who have made important contributions to the field of mechanical and process engineering. The prize is named for Aurel Stodola (1859-1942) who, as professor of thermo-chemistry and thermal mechanics, taught at ETH and carried out pioneering work on steam and mechanical engineering.

Friedlander began his address with a short overview of aerosol research. First works by C.T.R. Wilson were published towards the end of the 19th century (Wilson's fog chamber). In the 1920s aerosol coagulations were described for the first time, and these were followed by first aerosol interactions in the 1940s. Detection became possible in the 1960s. Aerosol research today deals with interaction at the level of nanoparticles. Friedlander places his own area of expertise in environmental and climatological research, areas he had been dedicated to for many years, he told the audience.

A short summary of current thoughts in science philosophy was delivered by Michael Hagner, ETH professor of science research. Adriano Aguzzi, Professor of Neuropathology at the teaching hospital of the University of Zurich and member of the ETH Board of Directors, summarised the latest state of prion research.