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Macroscopically homogeneous mixtures of p -nitroanisole ( p NA) and mesitylene (MES) can be selectively heated using microwave (MW) energy. The p NA solutes agglomerate into distinct phase domains on the attoliter-scale (1 aL = 10 −18 L), and these agglomerates can be MW-heated selectively to temperatures that far exceed the boiling point of the surrounding MES solvent. Here, a 1 : 20 mixture of p NA : MES is used as a mixed solvent for aryl Claisen rearrangement of allyl naphthyl ether (ANE). ANE itself does not heat effectively in the MW, but selective MW heating of p NA allows for transfer of thermal energy to ANE to accelerate rearrangement kinetics above what would be expected based on Arrhenius kinetics and the measured bulk solution temperature. This focused study builds on prior work and highlights 1 : 20 p NA : MES as a mixed solvent system to consider for strategically exploiting MW-specific thermal effects.
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RFTemp: Monitoring Microwave Oven Leakage to Estimate Food Temperature
Microwave ovens have been widely used in recent years to heat food quickly and efficiently. Users estimate the time to heat the food by prior knowledge or by trial and error process. However, this often results in the food being over-heated or under-heated, destroying the nutrients. In this paper, we present RFTemp, a system that can monitor microwave oven leakage to estimate the temperature of the food that is being heated and thus estimate the accurate time when the food has reached the targeted temperature. To design such a system, we propose an innovative microwave leakage sensing procedure and a novel water-equivalent food model to estimate food temperature. To evaluate the real-world performance of RFTemp we build a prototype using software defined radios and conducted experiments on various food items using household microwave ovens. We show that RFTemp can estimate the temperature of the food with a mean error of 5°C, 2x improvement over contactless infrared thermometer and sensors.
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- Award ID(s):
- 2018912
- PAR ID:
- 10394250
- Date Published:
- Journal Name:
- Proceedings of the ACM on Interactive, Mobile, Wearable and Ubiquitous Technologies
- Volume:
- 5
- Issue:
- 4
- ISSN:
- 2474-9567
- Page Range / eLocation ID:
- 1 to 25
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1145/3494967
