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Comment Re:Interesting; likely more limited than advertise (Score 1) 82

We don't have one in our lab! My company makes functionalised materials (so solid state) but most of the synthesis and research we do is standard organic chem. GCMS, NMR and ICP do us just fine. We did test a reflectance IR instrument but never managed to get any useful data - in fairness that's probably partly due to lack of expertise.

Interesting that you mention IR not being suitable for reaction monitoring: Mettler's ReactIR has generated quite a bit of hype (well, perhaps 5-10 years ago) and is really quite a nice bit of kit. Easily good enough for reactions on the ten-minutes to hours timescale.

And I am surprised by the statement that vibrational spectroscopy doesn't give you enough information

OK, perhaps that was unfair: for certain tasks it can be useful, and can give information that other techniques can't like bond strengths (and angles/strain perhaps?), but only with nice, pure samples. For routine organic synthesis though all the information you need can be got much more simply and intuitively (albeit expensively!) with NMR. You can get half-decent desktop NMR now, about the size of a PC.

Comment Re:Interesting; likely more limited than advertise (Score 1) 82

But even with a limited spectral resolution and sensitivity, it should be able to identify spectral signatures of typical herbicides and pesticides.

I would be amazed if it could. With a sufficiently large database to draw from, and clever processing, I can imagine being able to identify the bulk constituent, but anything else would be lost in the noise. It might be able to tell you if your apple is waxed or not, but not if it's got ppm levels of pesticides. TBH, I'll be pretty impressed if this could identify different plastics or other relatively pure materials. It is certainly a nice idea though.

There's a reason IR spectroscopy has fallen by the wayside in chemistry - it doesn't give you enough information, and just hasn't kept up with other techniques. It's used for specific tasks, such as monitoring a reaction, but it's not a go-to analysis technique any more.

Comment Re:Meanwhile, back at the point (Score 1) 674

So the cleaners can plug in their equipment. When the train is stationary, and doesn't have wild voltage fluctuations due to the circuitry not having regulators designed to cope with the variation in line voltage between when the train's accelerating and decelerating (i.e. pumping power back into the line).

Comment Re:could've been your place (Score 1) 431

THF itself isn't particularly risky,* I imagine it's the implications to the authorities that would be a concern. THF is an important solvent in making various amphetamine-type drugs - I'm not sure where, but I'd hazard a guess it's to do a Birch reduction on the imine

* Well, it does have a tendency to form explosive peroxides like most ether solvents, but it's not usually a problem unless you're distilling pure (no inhibitors) THF which has been left under air for a long time. Oh, and it's a suspected carcinogen, but not so bad healthwise as DCM, toluene, etc..

Comment Re:Don't foget (Score 3, Interesting) 186

Amazed ADoM (adom.de) hasn't been mentioned yet. I've been playing it for about 15 years on and off (and actually won for the first time this year!). It lacks the stupid stuff you can only learn from spoilers that Nethack has, and it's got a more consistent universe - no stupid Sokoban, no flash cameras and credit cards...

DCSS seems pretty nice too, not played much

Comment Re:Cue Ayn Rand worshipping Libetarians... (Score 1) 325

Really? Those same engines are tested by firing frozen chickens into them while they are running.

Ah, that reminds me of one lunchtime debate with a colleague when this factoid came up:

Me: ... yeah, I don't think they use live ones
Him: Nah, they use frozen chickens
Me: Defrosted though I'd think?
Him: No - at that altitude, they *would* be frozen
Me: ......

Comment Re:I'm starting to wonder... (Score 1) 182

I'm no doctor, but I think the cause of death is less likely to have been "[taking] part in an ice bucket challenge" than subsequently "leaping into [shallow] water from 25-metre high cliffs."

Ontopic, I think everyone who has ever used LN2 will have dipped their hand into it. You get a couple of seconds of feeling perfectly fine, then a very sudden searing cold burn. Where I work we were given felt gloves to use when dispensing it until I pointed out that if you actually get LN2 on them (rather than just handling cold metal) it will soak in and be right next to your skin. Now we just use standard marigolds.

Comment Re:Self propelled (carries it's own jet fuel) that (Score 1) 195

The prototype TGV was powered by dinosaur juice - I believe they swapped to electric mainly because of an increase in oil prices. Maintenance was probably also an issue (the prototype was gas turbine-electric which has a terrible record in the rail industry).

But yeah, electrification is the only sensible option - you're fixed to the route of the track anyway (or if not you've got bigger worries than where your power's coming from) so why not stick some OHLE alongside.

Comment Fastest? Depends how you define "train" (Score 1) 195

This "train" (debatable if it's a train if it's only one vehicle) would only hold the record for the fastest conventional wheeled train in the US anyway.

The record for the fastest railed vehicle in the US - hey, even the world - is more than an order of magnitude faster. I'll pass on having a ride though.

Comment Re:Maintenance for all trains is high (Score 1) 195

There is also the not small problem of grade. Trains dislike hills, with a grade over 1% being excessive to them. Cars routinely handle ten times this. Grades dictate routes. The only way around this is tunnels & bridges. Either way, cost per mile for a track is much higher than for a road. With costs born by one company, rather than all of us.

1% is too steep for a 10000 tonne freight train, it's nothing for an electrified passenger line. High speed lines commonly have gradients of 3 or 4%. For comparison, in the UK the maximum gradient guidance for a motorway is 3% (the steepest is 5.6%). Curvature is the main constraint with HSR requiring curve radii of ~3 miles compared to 0.5 miles for motorways.

Tunnelling is actually not a massive cost these days - to the point where nearly half of the planned HS2 line here in the UK will be tunnelled, not due to geology but to avoid land grab and spoiling the countryside (in some rich areas, obviously). Alternatively you can do as the Chinese and build elevated lines which both avoids geography to an extent and reduces the land grab - in China it was cheaper to build viaduct than on the ground for land purchase reasons alone.

Comment Re:The death of trains (Score 1) 195

High speed rail != high speed train

In the French (and even more so German) models, the high speed network continues on normal track beyond the dedicated high speed routes, allowing service to places which wouldn't merit their own line. This is where such accidents occur - the train involved is incidental.

In Japan and Spain the HSR network is self-contained since the track gauge is different to the conventional network - If the US did ever decide to build a line I would expect it to be the same. Not because of the gauge, but to allow HSR to use existing technology which would not pass US rail safety requirements.

Comment Re:The math(S) doesn't work (Score 1) 590

Last I checked, air expands when heated, so your lasers would need to point downwards. Secondly, air is pretty poor at absorbing EM radiation so you'd not be able to generate a "hot zone", you'd just heat up air in the line of your beam For a long way. Third, the amount of power you'd need would be astronomical (unless you trapped the hot air in a balloon for lift, which has been figured out for a while now).

Comment Re:I'm not British (Score 1) 160

Now that Ceefax is considered obsolete, those days are over. It sure makes it a lot harder for me to enjoy their broadcasts.

If you were still watching analogue TV then it certainly will be a lot harder to enjoy any broadcasts. Subtitles are available on digital using the red button - I'm pretty sure the BBC and possibly other broadcasters are obliged to provide subtitles.

Comment Re:Python (Score 1) 525

'Maths' is the correct spelling in English; 'math' is correct in American. In any case, a mis-spelling is not an issue of grammar, it is one of spelling.
A point of grammar would be pointing out that the verb 'solve' does not take an indirect object ('me') but would require a preposition to indicate the action occuring, viz:
* "For example, I created one which solved me the maths homework."
"For example, I created one which solved for me the maths homework."
"For example, I created one which solved the maths homework for me."

If mathematically you end up with the wrong answer, try multiplying by the page number.

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