My initial major as a freshman was English, which quickly changed to pre-pharmacy. In order to fulfill the breadth requirements, I bit the bullet and took freshman chemistry. This is when I realized I was a chemist! I enjoyed chemistry because of its fundamental connection to the organization of matter and to predictions of how molecules were formed and reacted. I knew some aspect of chemistry was my life path.
As an undergraduate at UCLA, I was in the chemical research group of Professor Michael Jung group, working on a directed research project. The group studied synthesis routes for natural products like terpenes, sterols, which are important for pharmaceuticals, and flavoring compounds. Although I was just an undergraduate, the graduate students and postdocs taught me lab skills important for molecular construction. The group was like a family and the experience reinforced my inclination to go into chemical research. I had early insight into the rewards of successful research during my undergraduate research experience in Professor Jung's group. My project focused on producing a synthesis protecting group compound called iodomethyl methyl ether. One day after many months of no success at the reaction, I showed Professor Jung the NMR-spectrum of my product. He realized to my surprise that I had found a new one-step synthesis for compound with an almost 100-percent yield. We even got a patent on this method and produced a paper in a major scientific journal. A major chemical manufacturing firm marketed this reaction method based on this discovery. Despite this success, I did not want to go to graduate school in organic synthesis, because the lab bench work was not something I wanted to do for the rest of my life. My professor was crestfallen, but respected my decision and mentored me, resulting in a successful application to the Geochemistry Graduate Program at UCLA.
As a geochemistry PhD student I began to work on research projects using molecular tracers to study and understand the sources and fate of carbonaceous matter in Earth systems. Eventually, my thesis became centered on the sources, composition and fate of atmospheric particulate matter using mass spectrometry to detect markers at ultra-trace levels. I had a very good mentoring relationship with Bernd Simoneit, my research professor at UCLA, where I started my graduate work on the origin of particular matter in the air, a whole new field at that time.
These fine particles in the atmosphere are important to study, because they have a high impact on human health. In urban areas with extensive traffic there is a high incidence in asthma and cardiac arrhythmia. The organic carbon compounds also influence atmospheric chemistry and climate. So if we understand the origin of the particulate matter that causes these effects, we could find a way to control emissions, improving health and reducing the impact of such compounds on physical and chemical processes in the atmosphere.
We were one of the first groups to use a mass spectrometer to analyze these particles, which are present on a low parts-per-billion scale, about 10 nanograms per cubic meter. This mass regime required new analytical technology, which I developed during my PhD research.
While still a graduate student, I attended a seminar and happened to sit next to Professor Glenn Cass, an expert on air quality from the California Institute of Technology, who was working on airborne particulate matter in the Los Angeles region. He was beginning to implement a major fine particle sampling network in LA and was excited to learn about the molecular-level chemical analysis methods I had developed to identify complex mixtures coating airborne particles. To make a long story short, this was the beginning of a decade-long collaboration that was the beginning of air quality management and control using organic molecular markers for source apportionment.
During my three-year postdoc at with Prof. Cass, we designed a new mass-balance model for organic markers, which matches the organic chemical profile of an air particulate sample to its emission sources. The chemical emission profiles of sources allow us to distinguish manmade, natural and photochemical components in airborne particles. Since then, we published over 30 papers on air quality management based on organic molecular marker technology. Many scientists have used our research as a basis for their work and I am now listed as a highly cited author compiled in the Thompson ISIHighlyCited.com database. It is good to know that this molecular level approach to air quality engineering has impacted the field of atmospheric chemistry and engineering and policy controls for urban sources of particulate matter.
I am now an associate professor in the Civil and Environmental Engineering Department in the School of Engineering at Rutgers University. Currently, I work on air quality problems and on alternative fuels and transportation infrastructure, especially in the New York-New Jersey area. Recently, the molecular marker technology I developed as a PhD student and postdoc has received special recognition with the 2001 and 2007 Haagen-Smit Awards for papers I co-authored on molecular composition, modeling, and source attribution of atmospheric fine particles. The award recognizes benchmark contributions to atmospheric chemistry and air quality research. Also, I am a member of the United Nations Intergovernmental Panel on Climate Change which along with Albert Gore Jr., share in two equal parts the Nobel Peace Prize for 2007 "for their efforts to build up and disseminate greater knowledge about man-made climate change, and to lay the foundations for the measures that are needed to counteract such change." These recognitions were unexpected, but deeply rewarding.
To attract more people to careers in science and technology, we should exposure them early to these fields. That's what motivated me in creating the Engineering Planet project (www.engineeringplanet.rutgers.edu), which involved a six-week summer program for middle school science teachers, where the "teacher scholars" worked alongside faculty and graduate student investigators on the NSF Biocomplexity research project. The teachers then developed new science modules that teach students how microbes can generate electricity or how to make asphalt pavement for better road performance. The modules were posted on the Rutgers Engineering Planet website to share more broadly and the teachers added the modules to current science curricula in their 7th and 8th grade classrooms, where each teacher scholar impacted about 125 students each academic year. Another way the project helped the middle school teacher scholars was by providing funding to perform these experiments in their classroom, or to buy a laptop or projection system to enhance access to the internet for web-based instructional resources during the class activity.
By empowering teachers, we empower, motivate and excite children early in their experiences in science and technology. It is important to capture kids' imagination in school, connecting them to the natural world and its phenomena through inquiry observation, and analysis and synthesis of information. Education should not be just "mac & cheese out of a box", but innovative and exciting. Also, teachers should let kids work in appropriate teams, where girls are not just taking the notes.
In my own teaching, I try to engage students by using recent articles and newspaper clippings in class. Air pollution, climate change, and energy are inter-related "hot topics" right now. This is of strong interest to students. Also, in class we delve into the annual reports of the major supplier of drinking water to Central New Jersey, comparing the chemical and physical properties of our local water to the U.S. Primary and Secondary Drinking Water standards. We look at the chemical composition of surface water (rivers and streams) and compare this to a 2002 U.S. Geological Survey of pharmaceuticals, endocrine disruptors (hormones), and pesticides in major rivers and streams in the U.S. These exercises drive home the need for future engineers who will grapple with the important "commons" problems of clean air and clean water for growing U.S. and global populations. Students also conduct a literature research review and synthesis project. Each student presents the results in class and the presentation is peer-reviewed by class members.
I teach my students to keep an eye on the relevance of the research, and also when they are deciding which career path they should take. During my life, I never thought of how my choices on research topics were going to affect my career, but focused on the questions that the research was based on. I chose the research that was important to me. That's what I would advise other people: follow the path with heart. And everything comes out right in the end.