Ph.D student, Chemistry
Balancing complex research with the simple pleasures of a good home cooked meal.
By Sharday Mosurinjohn
4th April 2013
Yaoting Zhang is a first year PhD student who joined the Mosey Group in Queen’s Department of Chemistry at the beginning of this year. Zhang made the move from Canada’s East Coast to Ontario in order to work with Dr. Nick Mosey, a specialist in theoretical and computational chemistry, after having completed three chemistry degrees in Nova Scotia – a Bachelor of Science at Acadia University, an honours BSc at Dalhousie University, and a Master of Applied Science at St Mary’s University. “I started out in computer science, but I switched to chemistry because my language skills at the time were better suited to that kind of work,” says Zhang, who is proficient in English, Russian, and Chinese. The path that he chose for practical reasons led to a fascination with quantum mechanics and the field of tribochemistry, a branch of chemistry dealing with the chemical and physicochemical changes of matter due to the influence of mechanical energy.
In his project, entitled “Quantum Chemical Simulations of Tribochemical Reactions,” Zhang looks at lubricants under high pressure. “I don’t do any bench chemistry,” explains Zhang. “Everything I do involves using computer software.” But even though all of Zhang’s experiments are computer simulations – most of which model reactions that occur at a time scale of a femtosecond, which is one millionth of a nanosecond (10 -15 of a second) – these operations can be costly in terms of the processing power they require. In order to illustrate his point, Zhang offers the example of trying to simulate a protein folding, which he says, with current technology “would take literally hundreds of years.” His own project requirements are more modest. “I define a cubical cell, into which I put a bunch of ‘molecules.’ In order to find out what kinds of chemicals might become lubricants under pressure, I manipulate basically two dimensions in these simulations: the type of molecule, and the amount of pressure applied to it.”
Specifically, the class of compounds Zhang works with is aldehyde-based molecules. Aldehydes are highly chemically reactive compounds and Zhang plans to control their reactivity by modifying their chemical structure. Zhang is particularly interested in how they can absorb the energy created by the pressure of two surfaces compressing them from either side, and actually turn that stress to advantage, by becoming a lubricant that allows those surfaces to slide against each other with less friction. This work has a number of possible applications in materials science industry, and that’s exactly where Zhang hopes this project will eventually take him.
In the meantime, Zhang has another goal; to get the food club he initiated this year ratified as an SGPS society. “We had a vegetarian food club back out East,” Zhang reminisces. “Cooking without meat was a great option for students for two reasons: first, it challenged us to be creative; and second, it was cheap!” To participate in Zhang’s club, members plan a dish, which they cook in a quantity sizeable enough to share, and bring it to their weekly meetings. Interest has been growing throughout the year, and Zhang is happy to continue welcoming any students who can likewise appreciate the value in balancing complex research with the simple pleasures of a good home-cooked meal.