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MgB2

241 karma · joined October 12, 2019

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MgB2··on Solar panels that plug into your wall
Why? It works in many countries without incident. What makes the US different?
MgB2··on Solar panels that plug into your wall
That's why in Germany you are limited to at most 800 W for you house with plug-in solar.

Of course your argument still stands, but we're talking about at most 3.5 A extra current, not 10 A. Home installations seem to be adequately sized to be able to handle that load. At least I'm not aware of any reported incidents, and people have been putting them up for quite a few years already. And typically, German regulations err on the side of caution.

But sure, with 110 V, you will have more problems with the extra current for the same power, so in the American grid there could be further precautions necessary.

MgB2··on Solar panels that plug into your wall
For panels and inverters, there's really too many to count, but mostly names that one is not typically familiar with. For integrated solutions, familiar names might for example be Anker Solix or Tepto, which offer battery storage with integrated AC inverters. I'm running an Anker Solix Solarbank 2 E1600, which is not really the latest model but rather cheap and runs nicely.

If you want to get an overview of the ecosystem, googling "Balkonkraftwerk" gives you the most relevant results.

MgB2··on Solar panels that plug into your wall
I really don't understand why most people here act like this is some weird unproven and unsafe technology. This is literally a solved problem. They are everywhere in Germany and it's no issue.

The inverters follow the grid AC and shut off their output if they are disconnected or unplugged, so the plug is never "hot". The power they input into your home wiring/the power grid is limited to 800 Watts as to not overload any installation. And the power meters know not to run backwards if you happen to feed power into the grid. Most can even meter how much power you fed in total (you're not going to get paid for it, though)

If you want, you can add battery storage that follows the same rules but lets you save excess power during the day to feed into your home at night or during demand spikes (washing machine, ...).

The setups are dirt cheap (often 200 - 300 EUR for an inverter and 800 - 1000 W(peak) of solar panels) and pay for themselves in about 1-3 years in saved electricity costs.

MgB2··on Gemini 3.7 Flash
Is it though? Hetzner gives you 1 TB of cloud storage for 4 USD per month.
MgB2··on Raspberry Pi Pico W as USB Wi-Fi Adapter
I'm kind of fascinated by the first diagram on the page. It sits so firmly in the uncanny valley for me and I can't put my finger on why. By itself every part looks ok and normal, but as a whole it just screams AI to me. I don't know if its the color choices or the composition or something else. It all just feels that little bit off.

I mean, I know its AI, the page says so itself, no one is trying to hide it. But it also just gives me AI vibes on such a subliminal level that I can't figure out why.

MgB2··on Basalt Woven Textile
Yes, they say its HDPE, but then conveniently in all their talk about sustainability, they somehow forget to talk about where HDPE actually comes from. Just that it being composed of carbon and hydrogen somehow makes it "clean". Which, I guess, is something you could also say about things like gasoline. Plastic shopping bags are also made of polyethylene. So are they sustainable as well?
MgB2··on Basalt Woven Textile
Sure it is. But it's also nowhere near cost competitive and so no one does. They also don't even claim they're using anything else than "normal" HDPE made from ethylene distilled from crude oil.
MgB2··on Basalt Woven Textile
Which is basically HDPE (plastic) foil with limestone filler. And a whole website full of marketing that somehow never mentions that 20% of the material is non-renewable (made from petroleum products) and not biodegradable.
MgB2··on An image of an archeologist adventurer who wears a hat and uses a bullwhip
The prompt didn't exactly describe Indiana Jones though. It left a lot of freedom for the model to make the "archeologist" e.g. female, Asian, put them in a different time period, have them wear a different kind of hat etc.

It didn't though, it just spat out what is basically a 1:1 copy of some Indiana Jones promo shoot. No where did the prompt ask for it to look like Harrison Ford.

MgB2··on An image of an archeologist adventurer who wears a hat and uses a bullwhip
Idk, the models generating what are basically 1:1 copies of the training data from pretty generic descriptions feels like a severe case of overfitting to me. What use is a generational model that just regurgitates the input?

I feel like the less advanced generations, maybe even because of their limitations in terms of size, were better at coming up with something that at least feels new.

In the end, other than for copyright-washing, why wouldn't I just use the original movie still/photo in the first place?

MgB2··on A forged Apple employee badge
- Germans use commas as the decimal separator, while periods are only used to separate thousands.

- As stated in one of the linked mastodon posts, the abbreviation for the Deutsche Mark was DM, not DEM

Also, I have no idea how the seller thought the German Red Cross would emboss their paper with a circle of stars. If anything, embossing the cross itself would make the most sense. Probably they had the tool on hand from another forgery where it may have made more sense.

MgB2··on Double-entry bookkeeping as a directed graph
That's basically what beancount does, isn't it? You basically have all the transactions in your plaintext files, and it generates the full ledgers from those on the fly once you want to do any evaluations.
MgB2··on Time to subsidize e-bikes?
Why gatekeep cycling? As far as I am concerned, anything that gets people out of their cars and onto bicycles is a good thing. If they like it, they might still switch to a normal bicycle later. If not, they're still an a bicycle instead of clogging the roads in their car
MgB2··on Time to subsidize e-bikes?
> Bikes that go faster or where one doesn’t need to pedal at all need a license plate and special insurance.

And, critically, they aren't allowed on bike lanes but have to be rode on the road instead, which makes them far less attractive for commuting in the city.

That's why the limited pedelecs are by far the most popular choice of E-Bike in Germany.

MgB2··on LCD TVs won’t see any further development
That's not how LCD Displays work, though.
MgB2··on Ask HN: What are you working on this weekend?
I'm working on a small program that continually monitors a region of the screen and OCRs and translates the text on screen if there are changes.

I want to use it improve my Italian skills by playing games with Italian subtitles and automatically having a translation on the second screen for reference.

MgB2··on Aluminum formate Al(HCOO)3: Earth-abundant, scalable, & material for CO2 capture
The compound presented here is, however, not an organoaluminum compound. Those have Al-C bonds and are indeed very reactive. Aluminum formate has the Al3+-ion coordinated only by oxygen, and will certainly not exhibit the reactivity you described.
MgB2··on Excel is pretty dang cool
PowerQuery can also use ranges inside the same worksheet as data sources. You can define either cell ranges or named tables as data sources and then use them in PowerQuery just like you would use any external data source.
MgB2··on Has the world become less colourful?
As others have pointed out, LED lights for general lighting (not those RGB strips for accent lighting) use phosphors with very broad emission bands. Unlike fluorescent lamps, they don't have big gaps in the spectrum. Just a dip in the cyan region. Just make sure to buy stuff with high CRI, preferably 90 or more, and you'll be fine.
MgB2··on Has the world become less colourful?
Exactly, if you get nice CRI 95 lamps you are unlikely to have a noticeable problem with color rendition.

But still beware, the CRI printed on the box (Ra) is kind of flawed since it is measured on unsaturated colors and does not include information about color renditions of red objects. You would have to look at the R9 value as well.

MgB2··on Has the world become less colourful?
For normal lighting LEDs the diode itself usually emits blue light (440-460 nm). Most of the blue photons are then absorbed by the phosphor or phosphors and reemitted at longer wavelengths (yellow-green to red). This converted light mixed with the remaining blue light gives the white color impression.

So no UV, although there are some concerns about the hazards of blue light. But if you ask me, you get much more blue light onto your retinas by just going outside on a sunny day than you'd ever get from normal LED lighting.

MgB2··on My Tungsten Cube (2019)
In Germany, you can get your tungsten at Smart Elements
MgB2··on My Tungsten Cube (2019)
I used to work with tungsten carbide cubes during my PhD thesis. They're used in multianvil high-pressure synthesis. With the right setup you can reach almost 20 GPa of pressure. Not as much as with diamond anvil cells, but you have more reasonable sample sizes (a few milligrams). And thats still like the pressure pretty deep into Earth's mantle.

I also used the opportunity to snap a neat picture of a polished WC cube: https://imgur.com/C2YiMqb.jpg

I always had fun handing them over to students because everyone is surprised by the sheer weight of these things.

Tungsten carbide is actually quite dangerous after it has been subjected to a lot of stress (Such as being stuck into a 1000 t press for a high-pressure synthesis). They have the mean tendecy to explode into super sharp pieces when you're not expecting it, so wear goggles.

MgB2··on Louvre makes its entire collection available online
The Tank Museum (formerly Bovington Tank Museum) is also doing a long-running series of "tank chats" on their exhibits. They don't only give some very interesting details (if you're into that sort of thing) but also give some deep historical context behind the vehicles.

https://www.youtube.com/playlist?list=PLBAEOsdxIbLPFEomzphaZ...

https://www.youtube.com/user/TheTankMuseum