Gai grew up in India, and was fascinated by science as a child. She was influenced by Marie Curie, her education, and her parents to study chemistry. However, at that time, it was not socially acceptance for women to have careers in the physical sciences. When she was a teenager, she was selected as a national science talent search scholar. Gai was educated at the University of Cambridge where she was awarded a PhD in 1974 for research on weak beam electron microscopy conducted in the Cavendish Laboratory.
Research and career
Gai has pioneered advanced in-situ electron microscopy applications in the chemical sciences. With Edward D. Boyes, she co-invented the atomic resolution environmental transmission electron microscope, which enables the visualisation and analysis on the atomic scale of dynamic gas-catalyst reactions underpinning key chemical processes. Her research has helped to understand better how catalysts function, leading to valuable new science. Her microscope and process inventions are being exploited worldwide by microscope manufacturers, chemical companies and researchers. In 2009, after years of development, Gai, who holds a chair in electron microscopy and was co-director of the York JEOL Nanocentre at the University of York, succeeded in creating a microscope capable of perceiving chemical reactions at the atomic scale. This is an advance on conventional microscopes at this scale, which can only view innate material in the "dead" conditions of a vacuum at room temperature. It is known as the atomic resolution environmental transmission electron microscope. With the help of colleagues, she built and refined the machine over two decades, beginning with a lower-resolution prototype when she was a postdoctoral researcher at the University of Oxford. She then spent 18 years in the US at chemical firm DuPont and the University of Delaware. Although her microscope is highly valuable to the scientific field, she made the decision to not patent it, saying, "I thought that if I patented it, no one else would be able to do work with it. I might earn some money, but I was not interested in that. I was interested in applications for many researchers, creating more fundamental science. So I decided not to patent it." She often advocates for women's roles in science, and has spoken about the challenge of having children as a woman scientist. She says, "what's needed to keep women in science; it's a very competitive field and they lag behind whether they are working or not. So I keep telling my female students to aim high."
