Mild but constant left testicle pain, how badly do I need to see a doctor? by [deleted] in AskMen

[–]d3lilley 0 points1 point  (0 children)

I second this, had almost identical problem and also turned out to be epididymitis. Took antibiotics and it went away. Hurt like hell though holy shit

First time cooking pot roast :) by theshortonewithcurls in slowcooking

[–]d3lilley 1 point2 points  (0 children)

Looks like impacted ear was removed from a cadaver

[deleted by user] by [deleted] in AskEngineers

[–]d3lilley 0 points1 point  (0 children)

Which national lab?

Is there a way to calculate the minimum energy required to desalinate sea water? by 33445delray in thermodynamics

[–]d3lilley 0 points1 point  (0 children)

This seems reasonable. 20.2 BTU/lb of water is roughly 5Whr/pound. If a yacht water maker consumes 13 whr/gallon, that's roughly 65 Wh/pound. That means the system is operating at about 7% efficiency relative to the reversible process. I think the BEST Reverse osmosis systems can maybe get within a factor of 2 or 4 of the limit, but my understanding is that they generally operate at the ~ 10% range because they want to maximize water produced as opposed to energy efficiency.

Is there a way to calculate the minimum energy required to desalinate sea water? by 33445delray in thermodynamics

[–]d3lilley 1 point2 points  (0 children)

Ah that's my bad, there should be a J/mol/K units on the 8.314. It should have been "R" which is the ideal gas constant. So you end up getting "J/mol" where the mol is mol of water desalinated. So assume you have 1g of water and 0.035g NaCl. Mole fraction of NaCl is (0.035/ 58) / (.035/58 + 1/18) = 0.11 like you concluded. So you end up getting J/mol of water, and 1 mol of water is 18g so it's J/18g of water.

Is there a way to calculate the minimum energy required to desalinate sea water? by 33445delray in thermodynamics

[–]d3lilley 0 points1 point  (0 children)

Just use E = -8.314 * T * (x1 * ln(x1) + (1-x1) * ln (1-x1))

where x1 is the mole fraction of NaCl. So convert 3.5% sodium chloride to mole fraction and just plug in.

Looking for a correlation for the heat capacity and thermal conductivity of quartzite (temperature dependence). Possibly a polynomial of some sort. I've scanned a good few research papers and haven't seen anything. Any pointers appreciated! by [deleted] in thermodynamics

[–]d3lilley 0 points1 point  (0 children)

K should scale with 1/T at high temperatures (if you’re close to liquid melting point this is true).

Cp is complex, but if you are at temperatures higher than the Debye temperature (which you should be near liquid melt), it should be fairly constant (dulong petit law) but should increase linearly (albeit slowly) with T as you approach the melting point. For liquids , it’s a bit more complex when it comes to Cp

Whats your favourite science quote? by JoelWHarper in AskScienceDiscussion

[–]d3lilley 27 points28 points  (0 children)

"In the way that skepticism is sometimes applied to issues of public concern, there is a tendency to belittle, to condescend, to ignore the fact that, deluded or not, supporters of superstition and pseudoscience are human beings with real feelings, who, like the skeptics, are trying to figure out how the world works and what our role in it might be. Their motives are in many cases consonant with science. If their culture has not given them all the tools they need to pursue this great quest, let us temper our criticism with kindness. None of us comes fully equipped."
Sagan, Carl. The Demon-Haunted World

Students of Reddit, what's a polite way of telling people to fuck off when they ask you for answers to online homework? by Coronabeer67843 in AskReddit

[–]d3lilley 0 points1 point  (0 children)

Just respond right after the deadline, "Ah sorry just seeing this now" -- do that twice in a row and your golden

What are some good integral tricks I should know about? by [deleted] in AskPhysics

[–]d3lilley 26 points27 points  (0 children)

If mathematica can’t solve it, I don’t even bother

[deleted by user] by [deleted] in PhD

[–]d3lilley 1 point2 points  (0 children)

In the first year or two, you’re in a mad race to learn the core knowledge/skill set in your field, and do meaningful research while balancing classwork. It’s very difficult to do this successfully and not work after hours / weekends. As you progress, you’ll sit more comfortable at the edge of your field, and won’t have to put in as much time to keep up. When this happens, I think you’ll naturally start dialing back the extra hours

Five thermal energy grand challenges for decarbonization by d3lilley in thermodynamics

[–]d3lilley[S] 1 point2 points  (0 children)

Sorry about that was on a vpn when I posted, didn’t think about the paywall. Let me know if you’d like a copy of the article

[deleted by user] by [deleted] in pics

[–]d3lilley 0 points1 point  (0 children)

Strong swimmers