John Cuthber
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Everything posted by John Cuthber
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super-duper toothbrush technology
John Cuthber replied to zaffy's topic in Microbiology and Immunology
I wouldn't. -
Or an observation.
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Does Hybridization Always result in superior genes?
John Cuthber replied to IvoryEbony's topic in Genetics
"Does Hybridization Always result in superior genes?" It is impossible to define "superior genes" in isolation from the environment. -
You seem strangely determined to overlook the heat gun which is odd because the importance of heating is the point of the OP's question. You can demonstrate the effect of pH on the colour of tannins by making lemon tea or, less drinkably, by adding ammonia to tea.
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Acids are well known for catalysing the charring of carbohydrates. https://www.sciencekids.co.nz/experiments/invisibleink.html And it's a pH effect more than anything else. As you say there's no need for a heat gun
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I presume it's this sort of thing. (The commentary is inaccurate, it' s the HCl that chars the wood rather than the ammonia.) It would probably work in an oven but I don't know if "350 degrees" wold be hot enough. Units are important. There's a risk that the HCl fumes would corrode the oven too. The HCl is very corrosive towards metals (and not very good for people either).
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What worries me is that people may be leaving the party because they see it as no longer supporting their hero: Trump. OK that makes republicans unelectable which is good, but it is still terrifying that people might think that way. They might not be leaving because they recognise that the Reps are crazy; they might be leaving because use they don't think the reps are crazy enough. What happened to Rep party membership when he was selected?
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It is probably better to buy the girl some flowers which might not work, than to buy a book that certainly won't work The authors usually rely on the fact that, when you realise you have been made a fool of, you will be too embarrassed to take them to court.
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Acetic acid/water azeotropes?
John Cuthber replied to The Backyard Biochemist's topic in Applied Chemistry
No, or , at least, not at atmospheric pressure. -
There goes the neighbourhood. https://en.wikipedia.org/wiki/Edgar_Cayce#Criticism You can't cite "clairvoyants" on a science site, and expect to be taken seriously.
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Yes. Do nothing about it. The outcome will be the same as anything you might try, but doing nothing is very cheap. Incidentally, you are taller than I am.
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coincidence /kəʊˈɪnsɪd(ə)ns/ Learn to pronounce noun 1. a remarkable concurrence of events or circumstances without apparent causal connection. "it was a coincidence that she was wearing a jersey like Laura's" Similar: accident chance serendipity fate a twist of fate destiny fortuity fortune providence freak hazard a piece of good fortune (a bit of) luck (a bit of) good luck a fluke a happy chance happenstance 2. the fact of corresponding in nature or in time of occurrence. "the coincidence of interest between the mining companies and certain politicians" Similar: co-occurrence coexistence conjunction simultaneity
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I didn't know they were making printed masks in 2017.
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We can't spend less money any more than we can drop the death toll. Expenditure goes up. And since any disaster lies in our future rather than or past we always head towards it. It's like saying "the nearer we get to the year 3000, the more people who will have died from tripping over a frog".
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Then they are unlikely to be in that sentence.
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Extended life of solid state light emitters...
John Cuthber replied to Externet's topic in Engineering
Depending on circumstances, the limiting factor might be something like a capacitor in the power supply. Good temperature control is also a big factor so dropping the power is almost certain to help. -
White spirit has a fairly strong smell and it will take a while to get rid of it. If you can arrange the fan to blow air out of the window (and take the smell with it) that will avoid having the fumes in the rest of the house. Leave the door to the room slightly open so the fan can draw air through from the rest of the house. The smell will go quicker if you have warm air drawn through the room, or warm it as it enters the room with a non flame radiator near the door. Soda and vinegar are not going to help here.