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fans of The tea have been doing the same criticism for years: it is not the same thing heat water in the microwave to do it the traditional way. Usually, when you heat a liquid, the source is usually radiate heat from below , as in a fire of kitchen. Using a process called convection , as the liquid in the bottom of the container is heated, it becomes less dense and moves towards the top, allowing more cold liquid to come in contact with the source. This eventually results in a uniform temperature throughout the container.
however, within a microwave , the electric field that acts as a heating source is everywhere. As all the container is warming, the process of convection does not occur, and at the end the liquid in the top ends up being much more hot that the liquid in the bottom. In the same way that happens when we heat a meal and it is cold at the bottom.
A team of researchers from the University of Science and Technology of China studied this behavior of warming is not uniform. To “fight it” and prepare the cup of tea is perfect, have presented a solution that has just been published in the journal “AIP Advances”.
silver has The key
So, you have designed a silver lining that is placed at the edge of the glass to heat up, with the aim of protect it from the effects of microwaves on the surface ddel liquid to be heated. The silver acts as a guide to waves, reducing the electric field at the top and blocking effectively the warm-up. This creates a process of convection, similar to traditional approaches, resulting in a more even temperature.
And while place silver on the microwave idea may sound dangerous , in fact metal structures similar have been used previously -and safely – in steamer and microwave rice cookers. “After carefully design the metallic structure in the appropriate size -that is to say, it’s not worth a piece of silver paper placed by hand in house for any person-the metallic trim, which is prone to ignition, is located in a force of a weak field, where you can completely avoid this process, therefore, it is safe,” explains in a press release Baoqing Zeng , one of the authors of the article and professor of science and electronic engineering in UESTC. That is to say, do not try this at home if they are not part of this study.
The cup silver helps liquids to heat evenly in a microwave – Baoqing Zeng
however, despite the fact that earlier we gave the example of the food heated in the microwave is also hot on all sides, this solution to the liquid not is in the case of solids, since there is a reaction-convection. “ there is a simple way to design a bowl or plate to achieve heating much better , ” says Zeng-. We can change the distribution of the field, but the change is very small, therefore the improvement is limited”.
The group is considering other ways to improve the even heating in solid foods, but the methods are currently too expensive for practical use. For now, focus their efforts on working with a manufacturer of microwave to commercialize its accessories in the microwave to liquid. Although, until then, surely the tea in the microwave, do not know as in a tea kettle.
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