On Saturday, November 18th, 2017, Prof. David B. Graves gave us a lecture which is entitled “Circumstances of US PhD Students of Today: Tackling Multi-Career Paths” at the Hiyoshi West Annex, the base of this Leading Program. Prof. Graves is currently the Professor of Department of Chemical and Biomolecular Engineering of University of California, Berkeley.
The main point of his lecture was that PhD students should look at boundaries between fields, where multi-fields can overlap and partially merge. Normally, science and engineering PhD students tend to deepen their research topics or to focus on them. As knowledge deepens in the field, researchers often seek to go even deeper, following more esoteric topics for novelty. However, it is important to learn another field in order to make a novel invention or to explore new areas. Prof. Graves explained it with two examples from his own areas of research which is plasma.
Plasma is the general term of natural ionized gas such as lightning, aurora and solar corona. Plasma can also be generated in man-made devices. When plasma reacts with oxygen, nitrogen and water vapor in the air atmosphere, it produces reactive oxygen and nitrogen species (RONS). These are also key immune system species that are generated naturally by the body in response to injury, infection and tumor suppression. These plasma-generated chemical species have recently been used for plasma medical treatment of head and neck cancers, for example. This is an example of research that moves beyond the existing boundaries between physics and bio-chemistry.
Another application of plasma is for agriculture. Fertilizer made from synthetic ammonia (NH3) is essential to feeding the world population, but the nitrogen in fertilizer creates big pollution problems. For example, some of the nitrogen in synthetic fertilizer is eventually lost as pollution to the air when animal waste decomposes to form gaseous ammonia. Plasma-generated nitric acid can be used to trap this ammonia, thereby increasing the nitrogen content of organic fertilizer and at the same time reducing pollution. Currently, the most energy-efficient way of producing ammonia industrially is at high temperature and pressure via the catalytic Haber-Bosch method. The plasma-based approach recycles valuable reactive nitrogen and reduces the need for manufacture of synthetic nitrogen fertilizer. Prof. Graves applies plasma technologies in an attempt to make agriculture more sustainable and less damaging to the environment.
As Prof. Graves explained in his lectures, it is definitely important for us to learn not only our in our major field of study but also in other fields and topics. I am sure that all of our program members were so motivated by his lecture to learn multiple fields from diversified standpoints more than ever.
（By Kentaro Yagi, Enrolled in 2017 Spring, M1, Graduate School of Science and Technology）
Prof. David B. Graves, Department of Chemical and Biomolecular Engineering of University of California, Berkeley.
Department of Chemical and Biomolecular Engineering of University of California, Berkeley official HP