
Here is a question I encountered sometime ago. ... read full post
Professor Philip Moriarty takes issue with a paper by scientists claiming to achieve room temperature superconductivity. ... read full post
In this preprint, the authors synthesize LK-99-like samples, and observe half-levitation similar to that seen in other recent videos. However, they perform a careful magnetization measurement and conclude that the sample is ferromagnetic. They also did a resistance measurement on a larger sample and found that the majority of the material is a semiconductor. This points to the half-levitation effect, which is mostly what got people excited, being a consequence of ferromagnetism (+ mechanical effects due to friction and sample shape), rather than the Meissner Effect. ... read full post
It's by far the best video to explain special relativity.
This replication by Huazhong University includes PPMS data, showing a strong signal of a diamagnetism transition at around 320K. It does not include a resistance measurement, however.
cross-posted from: https://discuss.tchncs.de/post/1312651
TLDR: To remove by shaking one would need accelerations high as 24g, which can damage the ear. A couple drops of vinegar or alcohol in the ear will lower the surface tension and make the fluid easier to remove
https://discuss.tchncs.de/pictrs/image/885670e5-8154-4cf9-b66c-4a722e5de763.webm
Hopefully not too off-topic.
Graphite is normally very soft and slippery, and is even able to act as a dry lubricant when finely powdered, however many sources claim that graphite powder can be highly abrasive, to the point of potentially destroying milling machines. Does anyone know how such a soft material can abrade metals?