Citaat:
Oorspronkelijk geplaatst door vanderzapig
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Google Translate vertaling naar Engels (
bron):
https://www.docdroid.net/UiUrs8c/kci-fi002955269-1-pdf
De naam "LK-99" verwijst naar "Lee en Kim, 1999", het jaar waarin beide heren vaststelden dat één van de vele keramische mengseltjes die ze maakten interessante eigenschappen had qua
magnetische susceptibiliteit.
In 2017 begonnen ze het materiaal te reproduceren. Slechts heel af en toe hadden de staaltjes de gewenste eigenschappen. En het was niet duidelijk onder welke voorwaarden.
Pas in 2020 kwam de doorbraak: indien een kwarts vacuümbuis barst bij het uit de oven halen, wordt hun materiaal op hoge temperatuur blootgesteld aan zuurstof. Dit zorgt dan blijkbaar voor de nodige veranderingen in de kristalstructuur om tot supergeleiding te komen.
Uit de vertaling:
Citaat:
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In 1999, a new attempt was made in a simple system by selecting . The manufacturing method is to sufficiently grind the selected elements with a pestle and subdivide them into 1g each in a 10 mm diameter quartz tube, and then use a vacuum pump to keep the inside of the quartz tube in a vacuum at 10ÿ3 Torr to propane to a length of about 15 cm . Seal the quartz tube with an oxygen torch. Thereafter, the quartz tube taken out of the furnace is cooled by heating in a furnace (Furnace, A-Jeon Industrial Co. Ltd) at 900 ° C. for 24 hours, and a sample is taken. It was well ground and sampled, and the magnetic susceptibility was measured using SQUiD (Superconducting quantum used interference device, MPMS-XL, Institute of Basic Science). Magnetic Property Fig. The same results as in Fig. 3a could be confirmed, and the reproducibility of the critical temperature through repeated experiments at the time. 3b and 3c were confirmed. However, due to a manufacturing method problem, it was not possible to find even the structure of a characteristic material that appears to have a critical temperature of over 300 K, which is assumed to be in a very small amount. While studying the superconductivity phenomenon amidst continuous suspicion, in 2017, based on these data, repeated experiments were conducted in earnest, and cases where the quartz tube was destroyed due to internal pressure during rapid cooling or reaction were found. It has been discovered that an amorphous form of material of unknown origin has unique magnetic properties.
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