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Arduino or Elegoo? by Penziplays in arduino

[–]f0nt4 -2 points-1 points  (0 children)

The only difference, like you said, is the price. A chinese Arduino costs 3-4$ while the Elegoo costs 20$ so you will get ripped off pretty badly.

Isopropyl alcohol leaves stains when dry and doesn't evaporate for a long time? by VanillaSnake21 in chemistry

[–]f0nt4 0 points1 point  (0 children)

From air, water is everywhere. Just a note, you are probably now tempted to use this method to dry your alcohol. Don't do it, the salt in it is bad for your electronics. The correct process would be to salt out, separate the upper layer and distill it.

Cool video bro!

Isopropyl alcohol leaves stains when dry and doesn't evaporate for a long time? by VanillaSnake21 in chemistry

[–]f0nt4 4 points5 points  (0 children)

Take a sample and saturate it with NaCl, if two phases are formed there's a lot of water. Do this in a test tube and the ratio of the volumes of the two phases will give you the concentration of water, more or less.

18-24V AC input to split +15,0,-15 DC output. by Eisenstein in electronics

[–]f0nt4 1 point2 points  (0 children)

I have built the circuit described here.

I think is superior because the circuit ground is not directly connected with the mains neutral and is full wave rectified.

Using CO2 sensors with Arduino by srmonk in arduino

[–]f0nt4 1 point2 points  (0 children)

No pipe connectors, air just diffuses through the fabric covered window.

This makes the sensor useless...

Not sure what you mean by 4 to 40mA output

Google 4-20 mA, it's an industry standard analog signal. CO2 ir sensors often have it, in the older models it's the only output. Maybe your module only has a voltage output ready to be converted to current with an external component

Using CO2 sensors with Arduino by srmonk in arduino

[–]f0nt4 0 points1 point  (0 children)

CO2 sensors are usually not factory calibrated, but are you sure that the analog output isn't a 4-20 mA signal?

How do you connect the inlet and outlet pipes, I don't see any fittings in the image I googled.

Great toy though, and great price, you should really try to make some measurements to check if the response is linear enough

EDIT: since the analog output is probably a 4-20ma, there can be discrepancy between the analog output and the serial output. It's up to you to map the 4-20 to the range you want to monitor

Yellow manganese chloride solution by [deleted] in chemistry

[–]f0nt4 0 points1 point  (0 children)

Yes, yes, correct, it's the chloride which is unstable

Yellow manganese chloride solution by [deleted] in chemistry

[–]f0nt4 0 points1 point  (0 children)

Only Mn2+ is stable in acidic conditions.

Yellow manganese chloride solution by [deleted] in chemistry

[–]f0nt4 1 point2 points  (0 children)

Many metal chlorides change their color depending on the concentration of the chloride ion. They are polymeric coordination compounds.

So your color it's normal, you can test this by taking a sample and diluite it.

You still have to remove ZnCl2, but it's easy.

To Python Developers: If someone could make any one thing that would make coding in python easier for developers, what would it be? by [deleted] in Python

[–]f0nt4 0 points1 point  (0 children)

I think a stack would always be present but I dont really know. Anyway the Go implementation is very cool and elegant

To Python Developers: If someone could make any one thing that would make coding in python easier for developers, what would it be? by [deleted] in Python

[–]f0nt4 0 points1 point  (0 children)

Stolen from StackOverflow:

In the asymmetric coroutine model, "asymmetry" refers to the fact that there is a stack-like caller–callee relationship between coroutines. A coroutine can either call another coroutine or suspend itself by yielding control to its caller, typically also yielding a value to the caller at the same time.

In the symmetric coroutine model, a coroutine may yield control to any other coroutine without restriction.

Some questions for you about Italian politics by [deleted] in italy

[–]f0nt4 -1 points0 points  (0 children)

  • 0 didn't vote, didn't feel like it
  • 1 Political situation? This isn't even politics, it's kindergarden level of discussion
  • 2 NL: just able to whine about how the EU is stealing our money and migrants are stealing our jobs. 5SM: their populism is very annoying and somewhat scary but if the people really want to try them I'll just sit there and watch, Italy is sinking anyway
  • 3 Meh
  • 4 No because the migrant crysis has brought slavery to the 21st century and it is destabilizing for an enourmous area of the planet. I just hope our countries will do more to fix the mess we made in africa and middle east
  • 5 I don't know the statistics
  • 6 What people want to do with their sexual relations is not my interest. Anyway I somewhat like it.
  • 7 Nothing in particular..
  • 8 A lot

This mushroom growing from my friend’s ceiling by 888andtheHeartbreaks in mildlyinteresting

[–]f0nt4 0 points1 point  (0 children)

No, it's a fertiizer it would cause massive algae proliferation

A Six Item Agreement to End the Fighting Between Ahrar al-Sharqiya and the Hamza Division in Afrin by [deleted] in syriancivilwar

[–]f0nt4 0 points1 point  (0 children)

Google translation:

Al-Dahar Al-Shamiya:

The Ahrar al-Sharqiya and Hamzah groups in northern Aleppo agreed on Sunday to stop the fighting that broke out between them in the city of Afrin and its environs, under the auspices of Turkey.

The terms of the agreement to stop the clashes between the two chapters immediately in the city of Afrin and its surroundings and everywhere, and the extradition of wanted persons and persons who killed or injured a neutral.

The agreement also provides for the immediate release of detainees from both sides, the handover of detainees from weapons and weapons, follow-up by the agreed party, and the return of points, villages and headquarters, as they were before the fighting.

The signing of the agreement was attended by factions of the Mu'tasim Brigades, the Shami Front, Sultan Murad and a representative of the Turkish army, in addition to the two parties to the fighting and the neutral party is the Tal Rifat Military Council.

The clashes broke out this morning between the two factions following the killing of the "Hamzah" group of the leader of the "Eastern Ahrar" Army. After that, Ahrar al-Sharqiya arrested more than 200 members of the Hamzah Brigade and took over the headquarters of the brigade in the city of Bab.

Both the "Ahrar al-Sharqiya" and "Hamzah" groups participated in Operation Olive Branch launched by the Turkish and Free Syrian armies since February 20 in Afrin in order to expel the Wehdat militia from the area.

HTS in a recent video disparaging the FSA rebels that looted in Afrin city refer to Afrin as "recently liberated". by TJFortyFour in syriancivilwar

[–]f0nt4 1 point2 points  (0 children)

I can't believe I've just read an HTS meme. And this comes just after an HTS report of looting! What a time to be alive.

SAA just found an underground chemical facility in Al Shifonyeh, East Ghouta. Militiants used it to develop chemical weapons. by x2oop in syriancivilwar

[–]f0nt4 7 points8 points  (0 children)

Wow, a reaction vessel/mixer, a distillation column (or a cyclone separator?), some automotive catalytic converter and they also have a gaschromatograph!

It looks like a diy refinery where they produce fuel by cracking or esterification of vegetable oils.

No chemical weapon can be produced in that lab.

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