Monthly Archives: April 2019

Horizon Event: The big EHT reveal

The Event Horizon Telescope team announces its major discovery following two intense and quiet years of data analysis on top of a longer period of development.   A nice testament to aperture synthesis and international collaboration as the rest of the world spirals into madness.  Damn!!!

Youtube Channel: National Science Foundation

Context for the interested public:
Youtube Channel: Sixty Symbols

 

Scrubbing bubbles: The pros and cons of cavitation

We routinely use ultrasonic cleaners to decontaminate all kinds of surfaces.  A little solvent, some buzzing, and jewelry, electronic parts, and pen nibs get degunked effectively.  Cavitation is responsible.  It is also responsible for damaging surfaces such as ship propellers and pump impellers.  The first video explains the physical chemistry behind the process and its (mostly) destructive effects.  The second shows it applied to cleaning vegetables which, surprisingly, is a research problem funded by the National Science Foundation.  Both videos show closeups of bubble collapse making the cleaning/damage mechanism much easier to understand.

Youtube Channel: IET Institute for Energy Technology

Youtube Channel: National Science Foundation

Addendum 7 April 2019: More detailed super-slowmo  videos from the EPFL group featured in the first video.
Source: CAVITATION BUBBLES IN VARIABLE GRAVITY

Seawater: Armando Hasudungan on carbohydrates

The reputation of carbohydrates waxes and wanes depending on trends in nutritional science and public interpretation.   Chemical facts that I learned years ago still hold.  Take one carbon, two hydrogen, and one oxygen, CH2O (or seawater, ha!) and repeat in quantity n to get the empirical formula for the carbohydrate family: (CH2O)n .  From there it quickly gets very interesting and very complicated.  These handed molecules can form five- and six-membered rings and the rings can join together in marvelously intricate ways.   Beyond mere aesthetics they form through sugars, starches, and cellulose the code, fuel, and structure of life.   Here is Armando Hasudungan explaining more than what I once knew but since have much forgotten about these compounds.  His channel is a gold mine for aged chemists and aspiring medical students.

Youtube Channel: Armando Hasudungan