exchemist
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Posts posted by exchemist
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2 hours ago, zhangchang said:
Perhaps we can design a device that combines temperature sensors with pyrotechnic components. When the temperature sensor senses a change in temperature, it will send a detonation signal to the electronic detonators that make up the initiating component, and then the electronic detonators will detonate. How can this process be achieved?
Central heating thermostat?
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5 hours ago, paulsutton said:
This was posted to the Fediverse , just sharing here so we can discuss here too.
‘We are moving in the wrong direction’: New UN report highlights the scale of global climate change
One question is, how many more reports are needed before we as a human race take things more seriously.
There is only so much as individuals we can do surely.
Paul
It’s a question of progressive pressure to change. We are moving quite a bit now: almost no senior politician any longer denies the need for action, and governments and industry are investing in the shift. Of course we have move faster but there won’t ever be a discrete tipping point.. People have get used to changes and find tangible upsides in it for them, especially when it impacts their personal lifestyles. We have not got far with that yet, apart from cars. Home heating is a big one.
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1 hour ago, geordief said:
Trump also has his own secular infallibility doctrine.
He makes "perfect" phone calls when they seem to an outsider to be anything but.
He is also able to declassify documents by the power of thought.
Perhaps they might give him the job in the Vatican and he can blow smoke up their arses when the election result is announced by his cronies
I don’t think the Vatican, for all its faults, would want to have anything to with Trump. The guy seems to be actually evil.
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5 hours ago, paulsutton said:
Excellent point here, things can be made too easy so we over rely on tech to do the most basic tasks for us, then when we need to actually do a task without tech we struggle.
I still prefer, what would be old fashioned paper maps, the advantage is, if inserted in a clear paper bag, will also work perfectly in all weathers, paper maps don't need batteries either. So being able to think about where places are in relation to current location is helpful.
I think there are also links between delaying conditions such as dementia and keeping the brain active and therefore healthy. Hence we have brain training activities.
Paul
I’m certainly with you 100% on maps. Like you I feel a need to know where I am going in relation to other places. I also like to have a mental picture of the journey. It makes me feel I am in charge rather than blindly following instructions.
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5 hours ago, studiot said:
The last 100 years or so has seen a steady reduction in the mental agility required for ordinary everyday living.
Folks no longer need to work out weights and measures, or calculate prices, totals or change to be given.
Modern 'scales' do all this and more.
You can just wave your phone or RFID card at the bus driver, sometimes you don't even get a ticket or receipt.
Reading is no longer required.
No it is conventional wisdom that as we progress through life and grow into old age, physical exercise is important towards retaining good physical health and agility.
So the question arises does the same thing occur with mental agility ( I can include mental health if you like but please don't concentrate on that)
In other words should we also use our brains or loose them ?
On the contrary it seems to me that modern life requires mastery of an ever-expanding battery of computerised tasks, mostly to be done on your own without help. So mental agility is still needed but of a different sort.
However I have certainly read of the importance of exercising the mind as one grows old. That’s one reason why I sing and why I do sudoku after lunch and wordle at teatime. And hang around science forums of course.
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23 minutes ago, Phi for All said:
As I understand it, a pope can only make infallible statements about church doctrine while holding office. It's not like everything they say is without error once they become pope.
Yes it is only ex cathedra pronouncements on faith and morals. Most popes are very sparing indeed in their use of this.
I think I recall this dodgy (and risky) doctrine was only formalised in the c.19th, at a time when the church was going through a phase of dogmatic absolutism.
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1 hour ago, paulsutton said:
This is sort of related to my post on Red Cabbage indicator in the Amateur Science section.
https://www.scienceforums.net/topic/131382-red-cabbage-indicator/
So in terms of experiments that cause a change in pH should this be referred to as increasing and decreasing pH of a solution / substance.
For example if I take Vinegar which is Acidic (so pH will be between i think 6 and 1, and add Sodium Hydrogen Carbonate, which is an Alkali (pH 8 to 14). then the acid either neutralised or becomes more alkali, so the pH has increased. pH 7 being neutral of course.
I am trying to write up an experiment or an idea I have had at least, and want to make sure I use the correct terminology.
Thanks
Paul
Yes, pH can increase or decrease, or one can speak of a low (acid) or high (basic) pH.
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17 minutes ago, geordief said:
I have lots of these and they date back some 30-60 years.(so no washing instructions on them)
Now I think I may have bed bugs or similar in my bed and so I want to clean the bedding.
Easy enough with sheets but I am not sure about the woolen blankets as the (=my) rule with wool is to wash at a cold water temperature-and this may not be very effective for killing these bed bugs
My suspicion is that it may be possible to go to a warmish temperature without damaging them but not the 90%that I am using on the sheets.
I doubt this is a problem many here will have faced but I can't seem to find another discussion forum dealing with washing clothes or similar.
Maybe ,I can use one as a Guinea pig first to see if they take very hot water without shrinking.
I don't suppose just airing them (for a few days) would do the job.
Bed bugs are bloodsucking insects. If you’ve got those you need to fumigate the entire bedroom, paying attention to the underside of the bed and mattress as well as the top.
But I doubt this is what you mean. If you mean dust mites, then washing should help. Woollens are washed not cold but at 30C usually. That should be OK. I would not go hotter if I were you.
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44 minutes ago, tmdarkmatter said:
Why would my concepts disagree with what we observe? I think it is rather that we cannot confirm if this concept is true because we cannot measure all the radiation hitting us and calculate its force nor can we confirm that spacetime curvature exists. There are no proofs. It is just that we are conformists. If spacetime curvature can only be confirmed by gravity and gravity can only be confirmed by spacetime curvature, than this is not science. And even if you melt both ideas and say that spacetime curvature is gravity, we can still remove the spacetime curvature and say that there is only gravity and nothing else. So we are still in the times of Newton, we just have to optimize our understanding of gravity taking into account that protons themselves are being bent by gravitation and that they are also redshifted. Spacetime curvature is nonsense. It is just "an idea quickly accepted by the world of scientists without any proofs" that made Einstein rich and famous and with it the western world became the winners of sime kind of "cold war of science" (just check the amount of nobel prizes by country to see what I mean). Unfortunately, it converted physics into some kind of religion and now it is impossible to propose new ideas without being classified as flat earther. The first condition necessary to be a scientist is not special skills or intelligence. The first conditions are being modest, being able to observe the world/universe, being able to listen to others and having good intentions for humanity. And your goal should not be to become rich and famous nor to treat others as flat earthers, just because they say something different to your unconfirmed theory. I know that you will now show me that the theory was confirmed several times, but if you really take your time and analyze the situation, you will always arrive at the same sentences I mentioned at the beginning.
I have a couple of questions:
- How does your radiation concept account for the time dilation we observe in communications satellites, which is accurately predicted by relativity?
- Are you an electrical engineer, by any chance?
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4 hours ago, MJ kihara said:
This thread intend to get input about the connection between the three issues outlined in the topic...mainstream argument is highly welcomed and wild suggestions is appreciated.
My take is this,you have two events in space-time with common origin such that t=t'=0 they are freefalling in the same space axis then you lorentz trasforms one event(t') towards to past the null line of the other(t)...the worldline of event(t') will be becoming closer to the null line from the upper part(increasing angle from time axis) while the space axis of event (t') will becoming closer to the null line from lower part(increasing angle from space axis),as the world line approaches the null line trying to go past it,it causes instabilities in the space-time,this instabilities show up as quantum fluctuations in a vacuum...what's your take?
Typo on the topic ...it's quantum fluctuation...pliz correction.
Makes no sense. Vacuum fluctuations arise due to the uncertainty principle. Nothing to do with relativity.
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3 minutes ago, paulsutton said:
It may be a hard water area, I will include a link to the wikipedia page as it may be helpful to others here too
https://en.wikipedia.org/wiki/Hard_water
I would guess you know what it is anyway,
Paul
Yup. Chalk. CaCO3.
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2 minutes ago, paulsutton said:
Cool, thanks will do that, yeah the infographic I have here explains the science behind it, pretty clever stuff, shows how nature seems to have an answer for all sorts of things. I would guess the washing up water goes blue as the liquid is usually alkaline.
I will see what I can make this week, the other stuff still works ok, just from a science view point it should be done properly and any anomalies removed as not to either impact results of experiments or the interpretation of experiments.
Paul
OK. By the way the anthocyanins in my red fruit turn blue just rinsed with water - before any detergent is added. So the water itself is sufficiently alkaline to do it. From looking it up, I see the pH of London water is in the range 8.0-8.5.
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45 minutes ago, paulsutton said:
This could explain why I seem to be getting my results. I didn't make the indicator one of the my local library staff made some up for the STEM group we run at the library
I think I have a few options
Firstly determine what colour red cabbage indicator is normally, as according to
https://www.youtube.com/watch?v=OMXMlWybv8A
It is more of a purple colour, so would suggest it is neutral
1. Make up a fresh batch, would using De-ionized water rather than tap water be better?
2. Repeat experiments and see if there is a change in result
I will keep trying,
Thank you again
Regards
Paul
Yes I would definitely use deionised water and a fresh, untreated cabbage. But I've never done this myself, I should stress. My experience is only in the kitchen, where I find the juice from red fruits goes distinctly blue when I rinse dishes. Almost all of them get the purple colour from anthocyanins, I believe, from blackcurrants to aubergines and red cabbage, so the same behaviour is expected, modified only by whatever acidity there may be in the fruit or vegetable involved.)
The reason for the colour change is quite interesting. These are conjugated ring systems with extensively delocalised π-orbitals. Protonation and deprotonation alters the bonding and thereby changes the energy gap between ground and first excited state, so that the molecule absorbs a different chunk of the visible spectrum.
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21 minutes ago, Sensei said:
These show different ranges in detail but in all cases the pH is 8 +/- 0.2or so.
So red cabbage should be blueish, if there are no acids around to distort it. But as @John Cuthber points out, at such a neutral pH, very small changes in H+ concentration have have a big effect on the value, so any traces of acid contamination can alter it quite a bit.
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1 hour ago, paulsutton said:
I am using some Red Cabbage indicator to investigate the pH of seawater collected locally. I seem to be getting results that imply that local seawater is acidic.
I have attached a photo and also attached a pH scale portion of the CompoundChem website
https://www.compoundchem.com/2017/05/18/red-cabbage/
According to : https://centerforsurfresearch.org/chemical-composition-of-seawater/
"Seawater has a slightly alkaline composition, ranging between 7.5 and 8.4".
Granted, seawater pH probably varies around the world. But this just seems way off.
In which case the colour should surely be more towards Purple / Blue
The pH indicator does work as I used so know that adding acids or alkalis produces the expected colours.
Has anyone else tried this ? Could there be a reason for the acidification, granted the sea was a bit rough when this was collected so there is a chance the colour and acidity could be due to something else being mixed in with the water.
I will try and collect some more seawater on a calm day see if that is any different.
Just asking as it may help my investigations further.
Thanks
Paul
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Paul, when I cook red cabbage the problem is to stop it turning blue when I sweat it with butter or add any water (I live in a hard water area). The normal way to do this in cookery is by adding acid, e.g slices of apple, or vinegar. How did you prepare the indicator? Did you buy a fresh red cabbage and extract the anthocyanin yourself, or does it come from something in a jar. If the latter, it will almost certainly have some sort of acidifier in it, to keep the colour.
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3 hours ago, observer1 said:
so basically,
it might be the organic stuff reacting with air while in water and turning yellow
to get around it, I started evaporating in a larger plate, so more surface area and faster evaporation, so not it is becoming nice long white crystals.
if i heat it it basically turns blackIf it goes black when heated, you have some organic material present.
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11 hours ago, Erina said:
Ah, sorry about the Nobel Prize claim, that was an Anglo-pshere effort, not just the UK. I got mixed up with that, it was from something else.
Daily Mail?
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23 minutes ago, Erina said:
I really don't know if this is worth pursuing on these forums any longer.
What a shame.
You are right. You've tried to explain your idea - and nobody here thinks it is a good one, for reasons they have explained. So that's that, really.
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5 minutes ago, CharonY said:
In that case why not have a genetic algorithm create an AI-driven curriculum and finance system that incorporates sustainable efficiency optimization using big data ecosystems that drill down toward a holistic education with resilient feedback logistics that minimizes pain points and provides an optimized customer journey that synergizes with hyperlocal strategies, aligns with global retargeting and moves the needle towards fully realized returns on investments?
Love it! This is just the sort of stream of impenetrable management bullshit that made me so grateful for the chance to take early retirement. 😃
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18 hours ago, Erina said:
The UK has as many Nobel Prizes as all of the EU countries combined (bar Germany). The Europeans love theory, but the Anglo-sphere does the practical, that is the system we need to maintain.
On a point of factual detail, this seems to be untrue.
According to this table: https://en.wikipedia.org/wiki/List_of_Nobel_laureates_by_country
The US has 403, the UK 137, Germany 114, France 72 and the rest of the EU countries between them have 171, or, if one excludes the recent admission of former Warsaw Pact countries, 131.
The UK does well, it is true, but one needs to bear in mind the advantage of language. Language is important for information sharing and collaboration in science. When I was at Oxford in the 1970s, the old-school dons were still advising chemists and physicists to learn German, as so much of the good research had been written in German. But in fact English was already becoming pre-eminent and that has of course continued. France, a country comparable to the UK and Germany in population and intellectual tradition, has done well, all things considered. So in Europe we have the big 3 industrial economies - the UK, Germany and France - dominating, which is to be expected.
In any event, Nobel prizes are not much use as a measure, if your aim is to contrast a supposed love of theory with supposed excellence at practice. Nobel prizes are awarded for theory just as much as for application, if not more so.
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1 hour ago, Genady said:
One needs to take in account a teacher/student relative weight.
Aha yes of course.
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16 minutes ago, Genady said:
4:1
Surely (1+√5)/2 : 1 ?
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35 minutes ago, CharonY said:
This comment actually demonstrates what I have been talking about. The role of education is fuzzy, with sometimes contradictory goals. Let's start with self-sufficient: what is required to be self-sufficient in a given role? Clearly, the required skill set is very different depending on the job. But especially for young folks, how and when do you know what career they will get into? Careers are unpredictable and often young folks need time well into adulthood to find their path and discover their interests where they want to hone their skills. How does it work if early on a parent decides that certain subjects should not be presented?
The second part is universal, but again this is something that many folks do not want. The reasons is that the ability to learn is not easily quizzable and those excelling at it tend to be in the minority. However, parents often think that better grades equal better careers. So it is better for students to only have subjects where they can be easily trained to perform in tests. I.e. there is a desire to remove more complex topics (where you are forced to learn). This is a trend we now start to see in universities, where students have an increasing input on how they want to be taught. Having students/parent pre-determine what they want to learn is similarly bad as having patients determine their treatment. Most do not know what they need or what style of teaching works with them. As such diverse exposure is critical for young minds to find their path. The narrower educations gets, the more likely folks it is that folks will miss their mark. Specialization can only come after folks have a good idea of the the range that is out there.
Moreover, learning to learn is the opposite of focused skill learning and it requires the broad exposure as you need to learn to integrate various forms and systems of knowledge, rather than excel in the application of a specialized form. Again, there are contradictory desires and with a presented pathway that is likely to fulfil neither.
Agree strongly with this, especially your last point.
I must say I have always objected to the narrow view that education is merely equipping students for a job, which seems to be what runs through @Erina's approach to the topic. People change careers, sometimes radically, fora variety of reasons. They need a rounded education to do that, not just what is necessary for one particular career path.
Even more fundamentally, education should equip them to get more out of life in the round, not just to do a job of work. Time spent teaching them how to read literature, how to appreciate the arts, how to understand history, are all helpful to an intelligent enjoyment of life. These things can give you some independence of your circumstances - even an unemployed person can read a book - a way to enjoy your leisure time more productively, and a better sense of balance in your life. The most enduring things I got from my schooldays, apart from an interest in physical science, were choral singing and rowing, which have been features of my life ever since. And as I get older I find the history I learnt is becoming useful, not least as that is what my son has chosen to study at university. So we can still have a conversation about his studies, even though I went the STEM route.
So yes, let's teach our children broadly, so they can pick routes from a variety, have the flexibility to change horses if they need to, and are equipped to stay sane and happy.
24 minutes ago, Phi for All said:You can't fiddle with one side of the equation only. If private schools can identify and cut waste, so can public ones. And they'll always be cheaper in the long run because they don't have to charge extra for profit.
Most private schools in the UK are non-profit entities. They charge a lot because they are in an arms race with their rivals for better facilities and better exam results.
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Earthquakes, volcanic eruptions, and solar flares are caused by the planets
in Speculations
Posted
Two questions:
- On what grounds do you claim terrestrial forces could not have been responsible?
- Have you calculated, or estimated, the magnitude of these interplanetary magnetic forces that you claim are implicated?