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Nuclear-Powered Cardiac Pacemakers

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Re: Nuclear-Powered Cardiac Pacemakers

#271

Post by eternityforest »

hwillis wrote: post #269
eternityforest wrote: post #238

Earlier quoted context omitted.

I wonder why solar phones don't exist? Even weak indoor light would eventually charge it. Maybe it would make people put phones in the sun all the time and wear out batteries with heat.

> Even weak indoor light would eventually charge it. No, it wouldn't. Sunlight is ~1 kW per m^2. A medium-sized room has maybe a couple 60 watt bulbs, spread over 10+ m^2, each of which radiates ~10 watts of actual light. Light indoors is pretty easily 1000x less than outdoors. Eyes work exceptionally well in low light conditions, so we don't even realize the enormous difference in brightness.

Current 60W bulbs are about 10W, probably giving off 3W of light.

If it's on for 8hrs a day and you capture all of it, on 1/5000th of a room, you get... 4mWh, or in reality, 0.7mWh because panels aren't perfect?

You could make a call in a few months of charge time. with a 3x3inch panel. But yeah, I suppose I was wrong and "eventually" is a bit of an understatement.

Re: Nuclear-Powered Cardiac Pacemakers

#272

Post by fomine3 »

eternityforest wrote: post #237
saalweachter wrote: post #65

Earlier quoted context omitted.

It's the scary goldilocks of nuclear waste. On the one extreme, you have the Elephant Foot at Chernobyl, which even today will kill you if you, like, go up and lick it. But it's not going to sneak up behind you, so just don't go over there. On the other extreme you have the release of radioactive water from Fukushima, which instantly dilutes to nothing in the vastness of the ocean. Meh. In the middle, you have radiat…

I wish phones had radiation detectors(Aside from camera based ones that aren't accurate and use battery). If 100M people had radiation detection, I'm sure we'd get a few hits every once in a while. Plus it can probably be done in roughly a headphone jack sized spot.

I just remembered it exists in 2012. https://www.softbank.jp/support/faq/view/11235 http://k-tai.sharp.co.jp/support/s/205sh/r_attention.html

Re: Nuclear-Powered Cardiac Pacemakers

#274

Post by xattt »

folmar wrote: post #207
xattt wrote: post #173

Earlier quoted context omitted.

A local company has developed a heat pump with a thermal energy storage system. Not sure how they do this, but I imagine there is some sort of insulated cinder blocks on a secondary loop that shuttles heat/cold to where it needs to go. (1) https://stash.energy/en/product/

They try very hard not to be specific, but the industrial heat accumulators are usually just water.

> … heat accumulator

Thank you for helping me learn a new HVAC term!

Re: Nuclear-Powered Cardiac Pacemakers

#275

Post by insane_dreamer »

nousermane wrote: post #85
hwillis wrote: post #33

Earlier quoted context omitted.

You really should not. 60 beats per minute means that in ten years the leads of a pacemaker will be bent *315 million* times. That's an order of magnitude higher than we typically test fatigue resistance, and even if we were that confident about being able to produce flawless materials, there are millions of different enzymes and acids and temperature fluctuations in the body. Any one of those could impact the fatigu…

> 315 million times. That's an order of magnitude higher than we typically test fatigue resistance Nah, it's not that bad. Decent mechanical keyboard switch is specified for 100 million clicks [1, or google for "switch million actuations"]. Surely good engineering can eek out another order of magnitude. Not to mention - pacemaker leads ("wires"), the only part that bends, have way less stress on them (= larger bend r…

non-comparable operating environments
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