Recent comments in /f/askscience

DontWorryImADr t1_j1b07jo wrote

Reply to comment by starmartyr in How do fusion scientists expect to produce enough Tritium to sustain D-T fusion (see text)? by DanTheTerrible

It better be, considering the volume of waste if all those batteries need replacement every 10 years. That would be the order of 1.89 billion kg of lithium every battery replacement cycle based upon 2030 numbers. Considering some of the issues with lithium, that would be all sorts of bad.

I don’t know that commercial scale recycling of said batteries is truly ready, but hence why it’s a big area of examination and study when it comes to converting transportation away from fossil fuels.

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Chagrinnish t1_j1avx5z wrote

Reply to comment by Bunslow in Why do we use phase change refrigerants? by samskiter

Here's a Goodman brand heat pump spec sheet (see p21) with COP numbers vs. ambient air temperature. They're giving a COP of 1.2 to 1.5 (120% to 150%) at -10F. It's going to be pretty cold before you'll want to use any resistive heat. The more important factor is that it can't put out as much heat (MBh in the chart) so it might not keep up.

Edit: Looking at price of Propane, Natural Gas, and electricity (in Iowa prices) you need a COP of 1.9 or 2.2, respectively, for the heat pump to be more cost effective. So that translates to the heat pump being more cost effiective around 5F and above vs propane or 15F vs natural gas. Unfortunately it's -6F right now :)

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seven_tech t1_j1asa41 wrote

Reply to comment by Calvert4096 in Why do we use phase change refrigerants? by samskiter

Haha, thanks. Yes, this was my whole point. I was never taught 'latent heat of fusion'. Nor were my colleagues. So we never had that ambiguity. Hence why I started the argument.

But hey, it's the internet. You'll get dragged for calling water wet...

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Triabolical_ t1_j1aq9t2 wrote

Reply to comment by derpderp3200 in How and why do diet and lifestyle changes reverse insulin resistance? by derpderp3200

Interesting.

Your HOMA-IR would suggest that you are mildly insulin resistant, though opinions differ on what a good threshold is.

I believe the symptoms you are getting and the low blood glucose is a sign of reactive hypoglycemia. I don't have enough knowledge about dumping syndrome to have any opinion on it.

I can tell you that I had pretty significant reactive (or postprandial) hypoglycemia - I'd get back from lunch and 90 minute later I'd really want to go to sleep.

For me, the fix was to switch from the sandwiches and burritos I was eating to something that was much, much lower in refined carbs - salads and burrito bowls without the carbs. I ended up full keto and these days I'm what I would call "keto adjacent".

Given that you are having issues with carbohydrate intake, going low-carb for a while would be an interesting experiment.

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seven_tech t1_j1apyhr wrote

Reply to comment by LionSuneater in Why do we use phase change refrigerants? by samskiter

Yes, I've had this argument several times.

We don't use that term in Australia. Because it's ambiguous. Fusion (more specifically nuclear fusion) is a specific physical process and its use in science is replacing fusion as in 'melting', which is a term dating back several hundred years. So we use melting now, because it's unambiguous otherwise.

You could argue, and many people would still agree, gay means happy. Yet you also wouldn't be unsurprised if people thought they were homosexual if you said 'I thought he was very gay' and many young people would never have heard gay used in any other context. Language changes and it's ambiguous. And science when speaking of fusion, doesn't like ambiguity.

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