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Engineering the Perfect Coffee Mug
Nerval's Lobster writes "From the annals of Really Important Science comes word that a research assistant who picked up his B.S. just seven months ago has invented a coffee mug designed to keep java at just the right piping-hot temperature for hours. Logan Maxwell, who got his undergraduate degree in chemical engineering from North Carolina State University in May, created the "Temperfect" mug as part of his senior design project for the College of Engineering. Most insulated mugs have two walls separated by a soft vacuum that insulates the temperature of a liquid inside from the temperature of the air outside. Maxwell's design has a third layer of insulation in a third wall wrapped around the inner basin of the mug. Inside is a chemical insulator that is solid at room temperature but melts into a liquid at 140 degrees Fahrenheit. The insulator – which Maxwell won't identify but swears is non-toxic – turns to liquid as it absorbs the extra heat of coffee poured into the mug at temperatures higher than 140 F, cooling it to a drinkable temperature quickly. As the heat of the coffee escapes, the insulating material releases heat through the inner wall of the mug to keep it hot as long as possible; a graph mapping the performance of a prototype shows it could keep a cup of coffee at between 128 F and 145 F for as long as 90 minutes. "Phase-change" coffee-mug insulation was patented during the 1960s, but has never been marketed because they are difficult and expensive to manufacture compared to simpler forms of insulation. While working on the Temperfect design, Maxwell met Belgian-born industrial designer Dean Verhoeven, president of consulting form Ancona Research, Inc., who had been working on a similar design and had already worked out how to manufacture a three-walled insulated mug cost effectively. The two co-founded a company called Joevo to manufacture the mugs." According to the Joevo Kickstarter page, you can get one starting at $40. For that much, I'd like a clever lid like this Contigo has.
This is just the same approach as Coffee Joulies, which is a former Kickstarter project. I have a bunch of these, they work well. No need for a custom mug.
In economics and business decision-making, a sunk cost is a retrospective (past) cost that has already been incurred and cannot be recovered. Sunk costs are sometimes contrasted with prospective costs, which are future costs that may be incurred or changed if an action is taken.
In traditional microeconomic theory, only prospective (future) costs are relevant to an investment decision. Traditional economics proposes that economic actors should not let sunk costs influence their decisions. Doing so would not be rationally assessing a decision exclusively on its own merits.
Sunk costs should not affect the rational decision-maker's best choice. However, until a decision-maker irreversibly commits resources, the prospective cost is an avoidable future cost and is properly included in any decision-making processes.
Evidence from behavioral economics suggests this theory fails to predict real-world behavior. Sunk costs do, in fact, influence actors' decisions because humans are prone to loss aversion and framing effects.
All good, except; gallium is hella expensive. And very very dense, therefore very heavy.
My money is on good old-fashioned paraffin wax, which (at least in the bulk candle variety that I bought in my hippie candle-making days) melts at exactly 140F.
Cheap and food-grade (it coats many candy items) and pretty light.