Brian Clegg's Blog, page 128

Molecule vs Molecule

In a number of recent posts I’ve looked at the ways that nanotechnology coatings like those produced by P2i can be used to make everything from mobile phones to trainers water repellent – and at the natural examples of this same phenomenon – but I haven’t really considered the science behind this technology – which is all about the electromagnetic interaction of molecules.

We’re probably most familiar with this kind of interaction in an attractive way. As I write this, there is a heavy frost outside. Water is turning from liquid to solid. Yet were it not for a particular molecular interaction, this would be an impossibility because water would boil below -70 °C. There would be no liquid or solid water on the Earth and, in all probability, no life.

The interaction that makes life possible is hydrogen bonding. This is an electromagnetic attraction between a hydrogen atom in one molecule, and an atom like oxygen, nitrogen or fluorine in a second molecule. When hydrogen is bonded to one of these atoms there is a relative positive charge on the hydrogen and a relative negative charge on the oxygen (say). This happens because the hydrogen atom’s only electron is in its bond, leaving a positively charged ‘end’ to the molecule, while the oxygen atom has four outer electrons not in its bonds, which are repelled away from the electrons in the bonds, giving it a negative charge.

Put two molecules alongside each other and the positively charged hydrogen is attracted to the negatively charged oxygen in its neighbour. The two molecules are drawn towards each other. There’s a force pulling the molecules together, and that means if you want to break them apart – say to boil liquid water – then it takes more energy that it otherwise would, as you have to overcome that force. Result: a much higher boiling point.

This inter-molecular attraction also accounts for another oddity that means aquatic creatures can survive in icy cold weather. Solid water – ice – is less dense than the liquid form, so it floats, leaving the water beneath still liquid. It’s sometimes said this is a unique property of water. It’s not – acetic acid and silicon, for instance, are both denser as a liquid than a solid – but it is unusual. It happens because the six-sided shape of a water crystal won’t fit with the way the hydrogen bonds pull the hydrogen of one water molecule towards the oxygen of another. To slot into the structure, these bonds have to stretch and twist, pulling water molecules further apart than they are in water’s most dense liquid form.

Hydrogen bonding would not be a good mechanism to consider if you wanted to keep liquids off an object. It would tend, rather, to keep them in place. So to produce a water resistant coating, you are looking instead for molecules that won’t attract. I have a personal interest in this. My father was an industrial chemist and was part of the team that developed one of the world’s first fabric conditioners. He used to bring home experimental jars of turquoise gloop from work to try out at home. And the principle behind a fabric conditioner or fabric softener is the opposite of cosy hydrogen bonds.

Such conditioners work by making clothes dirty with a special kind of dirt. Conditioners leave a thin residue on the fabric fibres. These molecules have several roles, but the significant one here is that they tend to repel each other, making the detailed structure of the fibres fluff up and giving the fabric a softer, more luxurious feel, lubricating the fibres when they move against each other.

This is very much fabric conditioner on fabric conditioner interaction. But to achieve a water-repellent coating we need to combine aspects of the two effects to get an interaction between the molecules in the coating and the water molecules that we are trying to get away from a product as quickly as possible.

P2i’s nanocoating is a polymer with molecules that are long-chains which can be either hydrocarbons or poly fluorinated . These start out as individual monomers – the molecules that will eventually be bound together in a polymer – which are exposed to a low power radio signal at 13.56 MHz to produce a plasma, a gas-like collection of ionised monomers, which then polymerize directly on the object being coated. It’s not a case of applying a polymer like sticking on an outer coating, but rather of creating it in place on all surfaces of the object to be protected.

The molecular action here is rather more subtle than in a fabric conditioner. The coated surface has a low surface energy – significantly lower than that of water. Surface energy is a way of describing how much ability the surface of a substance has to produce interactions. P2i’s coating is unusually reluctant to interact, giving it a very low surface energy, around 1/3 that of the non-stick substance PTFE (Teflon). This means that the water is much more attracted to itself, through hydrogen bonding, than it is to the surface of the material. The result is that rather than wetting the surface – spreading out as a thin layer – the water forms spherical drops, because most of the attraction the water molecules feel is towards other water molecules and with all this inward attraction the natural result in the formation of a sphere.

As the water is in self-contained droplets on the surface, it will roll off in these beads without interacting with the material. This is why you can have the kind of remarkable result shown in the Richard Hammond TV show where he pulled a ringing phone out of a toilet and it still worked. The water was not given a chance to wet the surface and short out or corrode the electronics.

We tend to think of a substance in terms of its macro properties – those that we can see and feel. But we can only properly understand what’s going on by taking a close up look. When it comes to how stuff works, it’s a molecule versus molecule world.

What shall we buy Fred?

Ho, ho, ho!I try to avoid the hard sell on my books here, but I like to think of this more as a helpful hand than a hard sell.

Every year we get faced with those difficult-to-buy-for people. You know the ones. They are often, but not always men. A pair of socks won't hack it as a present, and perfume is really not their thing. You would like to buy them a book... but don't really know what they like.

As long as they enjoy exercising their minds, you can't go wrong with a popular science book. As a particular incentive, I'm offering a range of my books at just £7.99 including first class post in the UK. What's more it'll be a signed book - always goes down well. But you have to be quick. I'm afraid it's too late for Christmas for all but UK buyers - last posting date is Thursday 20th, but for safety I would recommend getting any orders in by tomorrow, Tuesday 18th.

I've got on offer: Inflight Science, Build Your Own Time Machine, Gravity, Before the Big Bang, Upgrade Me and Armageddon Science. If you don't think any of those would do the trick, head over to www.popularscience.co.uk and check out the five star books for some more recommendations. But, of course, they probably won't be signed.

If you aren't giving books this Christmas... you aren't giving. (Actually that's rubbish, but I felt I should have some suitable salesy tag.) Not long to go now. We're in last minute territory. I would say 'Don't Panic!' but that's sadly inappropriate. Panic, immediately.

Artists and Spirit Mediums

My artistic masterpiece, created in 2 minutes on an iPad:
brown vista with blue thingsAs you may have gathered from previous posts, I am not a great fan of abstract or conceptual art. I can see the point of art that really grabs you when you look at it, or art that involves real skill - but when it is about painting a whole canvas the same colour, dribbling paint at random, or displaying a pile of bricks or an unmade bed, perlease!

It struck me recently that there is a parallel between abstract / conceptual artists and spirit mediums. There seems reasonable agreement that spirit mediums fall into two classes. There are the frauds who know perfectly well what they are doing is rubbish, but do it to get money out of the people they deceive, and there are the innocents who genuinely believe that what they are doing is genuine - even though their performances are just as worthless as the conscious fraudsters.

Similarly, I suspect there are abstract/conceptual artists who frankly know perfectly well they are producing worthless stuff, but sit back and enjoy the vast amounts of money thrown at them by the idiot but rich punters, and there are those who genuinely believe in what they do. Like the mediums, this doesn't make what they do any more worthwhile, but this section of the artistic population has no intention to con anyone.

And what of the glitterati of the art world - the gallery owners, the people with the big cheque books? They are the equivalent of the venues and audiences where the spirit mediums operate. Some know it's rubbish, but cynically make a profit, others are true believers, as deluded as some of the mediums/artists.

There you have it. The contemporary art world explained. The only difference from spirit mediums is that sceptics haven't turned their beady eyes and attacks on the art world. Yet.

In case you have any doubt that the art world is deluded, I leave you with a story told in Paul Bloom's book, How Pleasure Works :

David Hensel submitted his sculpture, a laughing head called One Day Closer to Paradise, to an open-submission contemporary art exhibition at the Royal Academy in London. He boxed it up with its plinth, a slate slab, for the head to rest on. The judges thought that these were two independent submissions, and they rejected the head but accepted the plinth.

A touch of literary madness

Every now and then I have the pleasure of appearing on the internet radio show Litopia After Dark. Usually this features interesting discussions of the latest events and developments in the literary world, but this was the Christmas special in the form of an office party (with games) and was totally bonkers.

If you want to hear Professor Elemental the ever so jolly British imperial rapper, Ian Winn, Ali Gardner, Dave Bartram and myself having a somewhat surreal conversation and playing some silly games while literary agent Peter Cox attempts (but fails) to maintain control - and perhaps join in and see if you can beat us to the answers - take a listen.

According to Mr Cox, Phyllis Diller once said "What I don’t like about office Christmas parties is looking for a job the next day." Exactly.

Why not dip in and enjoy, preferably with alcohol and mince pies. You can listen on the thingy below or nip over to the show's page.

Via Radio Litopia

Through a media glass darkly

Was it really only last year?There has been a lot of buzz in the UK media in the last couple of days about the 2011 summary census results, which are just out. However, strangely, the headlines missed out on one significant conclusion - how distorted some aspects of media reporting are.

Most English media organizations, with the exception of the BBC's recent major move to Salford, are based in London. This makes a lot of sense. The media world is one of communication, and though today's technology in principle means that you can work from anywhere, I appreciate (if only from the number of invitations to press events I turn down) that there are lot of opportunities for first hand interaction that require journalists to be in London.

However, the trouble is that whenever, say, a TV news programme wants to interview pupils or teachers in a school they are rather lazy. Being based in London, they will nearly always go to a London school. And  this will be totally non-representative of the country as a whole. This comes shining through in the census reports.

Take ethnicity. According to the reported census results, in London 45% of people identified themselves as 'white British'. In the population of England and Wales outside London that figure is 86%. It's pretty easy to see that doing a vox pop in London will not give you a representative ethnic mix. The same is very likely to be true of many other factors, like wealth distribution and occupation, but these weren't reported in the media response to the census, which for some reason concentrated on ethnicity and religious beliefs.

The message of the numbers is clear. Broadcasters and journalists need to break out of the capital and use more representative vox pops, school visits and other ways they portray the nation. It simply won't do to use London to represent the country as a whole, because it is patently so different to everywhere else. In many respects that's a good thing. We want our capital to be special, unusual and outstanding.  It shouldn't be average. But it is time that shoddy, lazy journalism stopped presenting such a misleading picture.

Psst - want to borrow an ebook?

Whether you are an author or a reader, ebooks have taken a bit of getting used to. But there is no doubt after years of posturing about the death of paper books that ebooks have finally taken off. It has been interesting to hear politician Margaret Hodge in her campaign to avoid using corporate tax dodgers like Starbucks, Amazon and Google that she has said that she loves her Kindle and is finding it a real pain going back to paper books.
Lovely ebooks! Borrow your ebooks 'ere!
Rip off an author!
I am not the kind of person who throws my hands in the air and bewails the coming of the ebook, nor one who forecasts the demise of paper books any time soon. Bear in mind 25% of the UK population doesn't even use the internet - I suspect a significantly higher percentage will resist ebooks for a good number of years to come (though admittedly some technophobes will not be enthusiastic readers). But I do think we need to keep an eye on the pros and cons of ebooks.
One aspect that has come to my eye recently is the facility called Overdrive that allows you to borrow ebooks from libraries.
At the moment (from my library, at least) the facility is fairly limited. It provides a small selection from popular authors, but mostly its pretty obscure stuff. However it won't necessarily stay that way. We could in principle see every ebook in existence available for borrowing this way. And what happens to the author's income then?
In the UK and a number of other European countries (but not in the US) there is a facility called PLR. This provides a small payment for the author (currently around 6p in the UK) when a book is borrowed, or rather it is based on the scaling up of borrowings from a number of sample libraries. It's not something that will make you rich. I just got my Irish PLR and it amounted to £6.50 for the year. But the point is that you are being paid for the use of your books.
The danger with ebook lending is that it is much closer in nature to buying ebooks than conventional library lending is to buying paper books. With an ebook you don't really care that you don't have anything to treasure and own, and unlike a library book it will be no more battered after its 1,000th loan. It could mean a whole lot fewer people buying ebooks. So if it is allowed, there need to be a number of restrictions.
One is that you can't lend the same ebook to many people at once - it should be (and the system allows it to be) a check-out/check-in resource. It is also possible that ebooks for loan should cost a lot more than for purchase. This isn't impossible - the same has always applied to videos/DVDs, where a loan copy cost the hire shop or library much more than buying a personal copy for yourself. And the final essential is that ebook lending is taken into PLR. And here we have a problem.
The UK government agreed in the Digital Economy Act 2010 that PLR could be extended to audiobooks and ebooks, and that audiobooks and ebooks counted legally as books for PLR purposes. But it has since announced that 'It will not be extending PLR at this time' and so PLR 'remains restricted to books which are printed and bound.' This is ludicrous and arbitrary. So it's time the government got its finger out and caught up. Otherwise ebook lending should be disallowed until they can get their act together.

Don't (always) make it your own

TV singing shows like the X-Factor are infamous for their repeated use of nauseous clichéd phrases like 'It has been a rollercoaster' or 'You have been on such a journey.' (Pause to cringe.) But one such phrase that hasn't had the attention it deserves is 'You have made that song your own.'

This is a feature of the age of recording stars. In the olden days, if a song was ascribed to anyone (and many weren't) it was the composer. Now, though, it's the performer. When competitors are asked what they are going to perform they don't say 'New York,' (say) they say 'New York by Alicia Keys,' not meaning she wrote it, but that she recorded it. So making a song your own is essentially about singing a song someone else has recorded, but putting your own mark on it so it doesn't sound like their recording, something this year's X-Factor finalists were particularly strong on.

That's all very well in the context of the show. If you do, say, a Michael Jackson song and do it purely in the style of Michael Jackson, you are an impersonator, not a performer in your own right. But the trouble is when you apply the same logic to music that doesn't have the taint of pre-ownership. And this is where things went horribly wrong when the X-Factor finalists sang Silent Night when the Downing Street Christmas tree was switched on. If you haven't seen it, and have a strong stomach, you can hear it at around the 42 second mark in the video below.



Oh dear. Each of the three tried very hard to make 'Silent Night' their own. And thoroughly ruined it. This is because with most decent music, what is important is the music, not how clever you can be in your rendition of it. If, for instance, you listen to different recordings of Beethoven piano sonatas or Byrd motets you will hear subtle differences of interpretation. But it is the music itself that shines through. The performer is secondary to the music. And these sad little people thought it ought to be the other way round.

I'm not saying Silent Night is a great piece of music. It is a simple tune written to be sung simply. But by attempting to make it their own, those three murdered it. Excruciating is probably the best word. Surely someone in the X-Factor production team could realise this. You can almost see David Cameron's blood curdle - just look at his expression in the starting still on the YouTube video above. Whether or not you support his politics, it's not fair that our Prime Minister had to suffer this. X-Factor - you should be ashamed of yourself. Learn a bit more about music, and a little less about showing off, please.

I'm Dreaming of a Green Christmas?

I've always had a lot of time for the Centre for Alternative Technology in the heart of Wales. Okay, the hippyish feel of the place isn't really me, but when I was writing Ecologic it proved a very helpful resource, and though they may be evangelical about being green, they don't go about it with a big stick like some of the green lobby.

For that reason I was rather taken with a press release they sent out on having a green Christmas. I am going to pass on that festive-but-caring message, though I will be throwing in one or two of my own comments as I go. So here we go. From now on the CAT gets the ordinary text and my comments are italic:


Christmas is a time for excesses and whilst its [sic] wonderful to kick back and relax with family and friends there are lots of things we can do to make Christmastime more sustainable and reduce our environmental impact. “ From reducing the amount of rubbish we produce, making our own Christmas decorations to buying ethically sourced and traded Christmas gifts there are loads of things we can do to make Christmas more sustainable.”

While I could quibble about their ability to punctuate (and what are those inverted commas for, guys?) - a perfectly sensible sentiment.
Buy ethically traded gifts, shops such as CAT's eco store offer a wide range of products, specially selected for their low environmental impact and eco- credentials. >> You may be thinking 'There's a time for composting toilets, but I don't want to find one under the Christmas tree, there are some rather entertaining gifts here (bamboo socks, anyone?) including some made from PLASTIC! I emphasise this merely to highlight that they are properly green, not knee-jerk green.Give someone a course, CAT short courses make the perfect present for family and friends to learn about more sustainable ways of living and allowing them to put those ideas into practice. >> Sorry, I really can't go for this one. Courses don't make a perfect present, they are very disappointing gifts. Don't do it, unless either a) you don't like the recipient or b) you know the recipients are really worthy people, the sort that like yurts.Reduce the millions of Christmas trees ending up in landfill sites. The alternatives are to get a tree with roots so it can be potted and reused next year, ensure that your local council will recycle dead trees (many councils grind them down into chips to be used as mulch in parks or gardens) or be creative: use branches, paint and cardboard. >> While the last suggestion is a joke - please don't do it - I do strongly encourage you to go for a rooted tree or to recycle. Our council takes them away: jolly convenient. The only thing with the rooted tree, if you put it in the ground after Christmas, leave it there and get another. Don't disturb it again, you risk killing it.Reuse your Christmas decorations. Bring out your old decorations rather than buying new ones every year, turn scratched CDs into personalised decorations, create decorations out of fruit and popcorn which can be fed to hungry birds in the new year. >> Ah, the Blue Peter spirit. Actually I don't think many of us need much encouraging to bring out old Christmas decorations. It's part of the delight of the season. By all means get one or two new ones (we need to support the economy) but don't go mad. For me, the only reason for using DIY decorations is because your children made them, so you can go 'Ahh!' Otherwise avoid like the plague unless you are really artistic. Trust me on this.Recycle Christmas cards and wrapping paper. Many charity shops sell gummed labels to stick over previous messages and addresses and E-cards are an eco alternative to paper based cards. Be creative when wrapping presents use fabric, magazine pages, aluminium foil that can be reused for cooking, to create beautiful, unique wrapping paper. >> A hearty 'Yes!' to the be creative bit. I've seen some brilliant gift bags, for instance, made from scraps of old wallpaper, sewn up and given a string handle. (Not sure about magazine pages, though.) By all means recycle cards and wrapping paper, but reusing them is just a bit... tacky.Reduce the number of polluting food miles your festive meals clock up by buying locally grown or reared produce. Locally produced, organic food tends to taste better too! For those Christmastime essentials from faraway places i.e. chocolate and coffee - make sure you buy Fairtrade products. >> Mixed feelings about this one. Yes to buy local. We get our turkey from a local farmer, and it's brilliant. And fresh local food may well taste better. It has been clearly established that organic food does NOT taste any better, and I try not to buy it myself as I don't approve of many things the Soil Association does. But their animal welfare standards are good. Our turkey is free range but not organic, and that's what I'd go for. Fair trade is fine, but don't think this is limited to the 'Fairtrade' label - that is a marketing organization. Recycle your scraps. Turn your vegetable peelings, fruit cores and nutshells into fertile compost and avoid unnecessarily using landfill sites. If you avoid composting cooked food, you will not attract unwanted wildlife and it won't smell. Many local authorities provide free c >> That's not me editing them, the original stopped like this. If your council does food recycling (some do) I'm all for it, but if it's DIY, do make sure that you avoid attracting rats etc. - they don't just go for cooked food - by making sure your composting is done in a closed, robust bin, rather than an open compost heap. Most of all, enjoy it! Don't feel guilty about not always being green in your Christmas celebrations. It's always a balance. But if you can have fun and be green too, why not? All together now: 'I'm dreaming of a green Christmas, just like the ones we never knew...'

Tread lightly on the fossil record

The view from my Southend hotel room on Wednesday morningOn Tuesday and Wednesday I spent two days in Southend, giving talks at the High School for Boys. Perhaps as karmic revenge for my referring to the town as 'sunny Southend' I woke up on Wednesday to a surprise snowfall, which was rather fun.

The talks went well (I think) but a useful bonus was a chance to attend a little symposium the school was running for a group of students. Said students were entering a competition to write a piece about science and religion, so the school put together a panel of five of their teachers, who each gave their personal opinion on science v religion, from an out-and-out atheist perspective to one that put the two on very much equal footing and could see no conflict between them.

The students were then given the chance to ask questions of the teachers. One, rather daringly, questioned a statement from the head teacher that while he had no problem with evolution, we need to recognize that as a theory it has some big problems. Would the head like to identify one of these problems, asked the bold student.

The head responded that the fossil record does not provide good evidence for evolution.  Not that it counters evolution, but is not sufficient to support it. With the thoughts of what my friend Henry Gee would say, who gets rather hot under the collar when the fossil record is waved around in a dangerous fashion, I waded in and pointed out that the fossil record is inherently incomplete in a big way, and any attempt to use it to cast doubt on evolution was dubious at best.

Ah yes, said the head, but the fact remains that there are not, for example, enough dead-end fossils. We should expect many more fossils of creatures that were evolutionary errors, the outcome of random variation gone wrong.

A breakfast view that morningNow this, I admit, is where I chickened out. Bear in mind that this was the head of the school that was employing me and (I hope!) may do so again in the future. So rather than come back on that remark, I let it lie. (I also thought it was wrong to hog the debate, when it was supposed to be for the students to ask questions.)

However, it's not going to stop me responding now. I know very little of palaeontology and the likes of Dr Gee are welcome to correct me on this, but my response would have been 'So what?' I'm not at all surprised there aren't many dead-ends for three reasons. One is that by definition many dead-ends would be, well dead-ends. They'd be one-offs. Chances of being fossilized? Vanishingly small.

Then what I always feel is the most amazing aspect of evolution, something that isn't made enough of. This is that every individual creature throughout history has been the same species as its parent. Even though if you follow back through our parental history you will eventually get back to bacteria-like ancestors, you will never see a species change from one generation to the next. It's a glorious paradox. So inevitably the first step down a dead-end will be indistinguishable from a non dead-end fossil.

Finally, I very much doubt how well we can deduce whether or not many fossils are dead-ends, bearing in mind what a fossil is. There may be some where it's pretty obvious but surely there will be many where it won't. To use a breeding rather than evolutionary analogy, I doubt if anyone looking at a fossilized mule would say 'that's a dead-end animal. It won't continue the line.' But the fact is a mule is just that.

As for the religion v science debate it was inevitably open ended. But it was fun trying and much kudos to the school for trying it.

A little brain work

I'm just about to catch a train to sunny Southend for a couple of days of talks, but before I go, I'll leave you with a little brain stretching challenge.


I have two bottles, one containing water and the other containing wine. I pour one measure of wine into the water bottle. I then pour an equal measure from the water bottle back into the wine bottle. At the end, there is just as much water in the wine as there is wine in the water. Which of the following have to be true to make this possible (you can choose more than one):

The bottles are the same sizeThe water and wine are thoroughly mixed after the measure is poured into the water bottle.The wine and water have to be thoroughly mixed after the measure is poured back into the wine bottleThe wine has the same density as the waterThe water and wine are miscible

… or is it impossible to be certain that there is just as much water in the wine as there is wine in the water?

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Don't go any further until you've attempted some sort of answer.

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Last chance to consider your answer.

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In fact, none of the conditions have to hold true - there will always be just as much wine in the water as water in the wine. Think of it like this: at the end of the process, the wine bottle holds exactly the same amount as it did initially, so it must have had exactly the same amount of water added to it as wine was removed.

Notice how the way that the question was phrased can distract you from the true facts. Even if you got the right answer, the chances are that the phrasing proved a distraction. You probably worried about partial mixing of water and wine, for example. Sometimes re-phrasing the question is an essential for knowledge gathering and creativity.