I am not convinced a single lamp placed over the dining table would provide sufficient irradiance to inactivate viruses and other pathogens in the large room. Consider having an infected individual sneeze or cough at the table. The expiration jet would spread so rapidly. This lamp is like a tiny flashlight placed above the dining table. Furthermore, far UV gets absorbed by oxygen in the air. The net irradiance of far uv is worse than 254 nm at a fixed distance from two equivalent (in power and form) sources.
The lamp would be effective if you were able to quickly circulate the air in the room past the lamp.
Yeah, what responsibly deployed far-UV is definitely not is an instant kill beam that immediately inactivates exhaled pathogens. I estimate it takes 100 mW of far-UV about 5 minutes to inactivate 90% of the flu/covid in a 250 sqft room (10 minutes to get to 99%), assuming the air is well-mixed. Far-UV should be thought of as a super-powerful quiet air filter more than anything else--it prevents infectious aerosols from building up in a space, which can matter a lot. You don't necessarily immediately get infected just because someone infected coughed near you--you might only get infected if you spend a long time near them, sharing their air. Continuously cleaning the air prevents these kinds of infections, and can make the infections that do still happen less severe.
You're totally right that circulating the air is important though! Definitely don't use far-UV in totally still air. But you don't necessarily need a LOT of air movement to achieve "good" mixing. Often just an air-change or so of ventilation is enough--just think about what would happen if you started smoking indoors. The smoke would be ~everywhere pretty fast.
The oxygen absorption at 222nm is not significant however--it's enough to produce a bit of ozone (less than you'd get from just opening a window), but not enough to actually absorb a significant amount of radiation. 222nm lamps are generally less powerful than 254nm lamps anyway, but because 254nm is much less safe, those systems have to be deployed in ways that often reduce their efficacy--in special louvred fixtures that kill most of their output or in portable units/ducts that constrain their effectiveness.
It is wild that the founders have very little experience in the space, and that their claims are based on sparse research. That said, the Substack article doesn't seem any more credible. Other than the name DC Fusion LLC, I missed any indications that the founder was working on a fusion startup. The article correctly identifies as an opinion piece but doesn't seem worthy of credible referencing.
I don’t have the expertise to say whether I agree with the conclusions of the post but the experience and track records of the founders are surely relevant? Happy to be shown evidence that these sections of the post are wrong.
Someone help me understand why the Ray-Ban branding? Meta should be able to make the frames themselves. Ray-Ban doesn't seem to be a strong enough brand that Meta couldn't go it solo and build a glasses brand themselves.
Nice work. I like the simple, unobtrusive and ad-free interface. I have kids who could use this although you face lots of competition for their very limited allotted active screen time [1]. The 6 yo gets 45 mins a week on the computer, usually opting for PBSkids, Kodable or Scratch. The 3 yo gets 15 mins usually opting for guided digital canvas painting as she learns to use a mouse.
There are a few good no-screen puzzle books for kids (lookup the ones by Usborne).
As a recent publisher of an interactive children's book [2], I am seeing more sales of the physical books than the digital/web editions despite the latter having more features including an element of teaching math.
Curious if you considered publishing a physical book with these concepts/math puzzles?
[1] This app inspires me to upgrade some of their passive screen time (TV) to more of your and similar apps
Yes, I am working on a Activity book for kids based on similar kind of games which I would be publishing sometime later this year. I've published a Math Brain Teaser book back in April and yes I can see the sales going up but not significant though. I'm still learning the art of marketing. Would love to know if you've any tips for me since you being an established author
I'm a debut author and not established by any means. I do have marketing experience and can provide the following suggestions:
+ Put all apps and books under one umbrella brand. Your book doesn't have a unique name associated with it. Little Math Genius or Little Math Whiz, for example.
+ Setup an umbrella website (littlemathwhiz dot com) and blog
+ Start aggregating a user mailing list where you can provide gentle updates (beta test new features on quizmathgenius, new book announcement etc)
Thank you for the feedback, I really appreciate it. Building my own brand and website has been on my mind for a long time, and this year I’m finally planning to focus on it seriously. I’m aiming to take this full-time since I truly enjoy working with subjects like Math and Critical Thinking
So with any conventional transistor including the GaN HEMT, the input/gate capacitance must be charged in order for the transistor to turn on. The turn on and off (discharging the input and the output capacitance) is predictable, and is the job of a gate driver integrated circuit.
It appears to me that while the effective input capacitance is reduced with HZO, the gate driver would need to be special to deal with the changing capacitance.
The article implies that the Berkeley team has been researching the use of feroelectrics in Si devices for 20 years. Are there Si mosfets in production with this material on the gate?
Thanks! The story images were made in Google Whisk. The tool allows you to generate a character and then apply the character to a scene separately defined. While more advanced than other image generation platforms, it isn't perfect and the images required lots of editing in GIMP. The vectors (achievement stickers, play cash) were made in Inkscape.
Thank you! I have been an Emacs user/consumer for many years. This project finally got me into the proverbial weeds, a fun venture, learning elisp, exploring the Org code base especially around the export backends [1]. It was useful going through the one.el source code as well, and I now write my blog in Emacs, rendering it using this package [2].
Ink looks iteresting! Twinery provides a nice visual editor for the passages and branches which I found appealing. Ultimately, I used Mermaid to create visual snapshots of the story which were useful when editing the physical book.
Some of the graphics indicate a contiguous building but it makes no sense to be constructed that way. The footprint probably includes power generation, power conversion, cooling systems, and compute centers as distinct blocks/buildings within the site.
The lamp would be effective if you were able to quickly circulate the air in the room past the lamp.