The following posts have no fixed theme or style, but I hope you enjoy reading them!

Saturday, 29 March 2008

One of those grumpy, how-I'm-feeling-today posts

"There'll be rain on our wedding day
Rotting roses in my bouquet
There'll be rain on our wedding day
Grey be the sky
Too late to cry"
Slow - The Cardigans

I feel a bit grumpy at the moment, although not in an angry way. It's as if I am suppressing something, so I feel slightly agitated and devoid of whichever emotions I'm supposed to be feeling.

I guess a lot has happened recently:
At university, I had my last lectures of my undergraduate time although I still have a few seminars and lots of work to do next term. I am sad not to have any more lectures because I enjoy them, but I'm not sure how much I will miss them and the opportunity they give to learn some quite important and difficult things relatively easily (more easily than reading, for example).

Also at university, I handed in my bigass final year project. I'm glad to have handed the project in, but I made the mistake of re-reading it after handing it in, and spotting all the ways I could have improved it. Nevertheless I'm not too unhappy with it, but now it is gone I have to look forward to the exams in June and think about time after June too. Revision and job-hunting are two activities I REALLY don't enjoy doing, so the reality of my post-project time has not lived up to expectations.

On top of that, my gran died. She was a lovely old lady. Her husband (my grandfather) died before I was born, and her son (my Dad) in 2000. But she put up with these things amazingly, particularly as she was living alone. She was old-fashioned, intelligent and dignified. Well, she was, but her health had been declining steadily over the past few years, starting with her eyesight going as a result of diabetes and ending in a nursing home she had only recently moved into. She did not show people her feelings much, but that meant that getting a glimpse of them was a special occasion that made you feel special. I don't know how much I will miss her, but I'm sure there will be times when I miss her a lot or would have liked to talk to her or ask her something. It will be odd not to see her at Christmas, or think of her going on holiday to Wales every summer.

Talking about this is probably what I need to do, but as always, finding the right person is difficult. Which is why I end up writing a moody blog post like this.

Monday, 17 March 2008

Cardigans on the BBC

Despite reading the BBC website religiously, this article slipped by me until I had a good read of the forum on the Cardigans website. It seems that someone at the BBC did some good research and has summarised where the Cardigans are at very successfully - hopefully plenty of people read it and will go and buy their new best of or the rest of their music!

Saturday, 15 March 2008

Everyone wants to be me

...when I have a potato this good

Friday, 14 March 2008

Wie Nanoröhren etwas besonders sind

Vor Weihnachten habe ich ein Projekt über Nanoröhren in der Uni geführt. Ich habe entdeckt, wie interessant das Material ist. Sie sind sehr oft in der Nachrichten, aber die Nachrichten kümmern sich sehr oft an die Anwendungen, ohne das Material zu verstehen.

Haben Sie etwas von Buckybälle gehört? Sie sind kleine Bälle aus Kohlenstoff, die sich in Rauch befinden. Sie bestehen aus 60 Atome Kohlenstoff und sehen wie kleine Fussbälle aus. Sie können sich vorstellen, man könnte die Bälle verlängern, und noch ein paar Atome in der Mitte stecken. Und Wissenschaftler sehen doch, dass es auch Moleküle mit 70, 80, 90 Atome gibt. Nach genügend Atome eingebaut worden sind, ist es schon eine Röhre geworden. Man sieht wie klein die Struktur ist, wenn man denkt, sie hat erst einen Umkreis von 10 Atome! Der Durchmesser ist ungefähr einen Nanometer.

Die Atome sind, wie auch in Graphit, in Sechseckformen ausgelegt. In Graphit gibt es Schichten von Atomen in Sechsecken, also ist eine Nanoröhre einfach ein Teil Graphit der aufgerollt wurde. Man kann mehrere Schichten von Graphit aufrollen, um eine Multi-Wand Nanoröhre zu machen.

Man hört sehr viel über Nanotechnologie, weil in Nanotechnologie die einzelne Atome wichtig sind, denn die ganze Struktur ist so klein. So ist es anders als normale Technologie. Wenn Strukture so klein sind, sind sie auch anders wie normal. Zum Beispiel, Materialien die ein paar Nanometer lang sind, sind selten spröd und zerbrechlich.

Nanoröhren sind sehr steif und fest. In Vergleich mit Stahl sind sie 1000 Mal steifer (hoffentlich habe ich das richtige Wort gefunden für "stiff" - ich meine, dass man nicht einfach sie recken kann) und sie sind sind gar nicht so schwer. Eine Nanoröhre kann auch leitend oder halbleitend sein (es kommt auf wie die Sechsecken sich ausrichten an). Das Problem ist so; einzelne Nanoröhren sind etwas besonders, aber es ist schwierig, davon ein Faser zu machen, der selbst auch so gut ist.

Die Möglichkeiten für solche Materialien sind enorm. Aber es endet noch nicht. Man kann auch andere Materialien auf der Wand wachsen lassen, die selbst interessant sind. Katalysator sind eine Möglichkeit, da sie eine grosse Oberfläche brauchen. Also Nanoröhren sind stark und steif, haben interessanter elektrische Eigenschaften, und können auch ein Basis für andere Nanomaterialien sein. Deshalb gibt es so viele Artikel in Zeitungen, Zeitschriften und im Internet. Und deswegen finde ich sie auch interessant!

Sunday, 9 March 2008

on Gran Turismo

The first Cardigans album I bought was Gran Turismo, having heard "Erase/Rewind" and "My Favourite Game" on the radio. Of course, I wanted more of the same catchy, bouncey rock music, but that's not what Gran Turismo is about. It's the coldest record imaginable, full of tension and stress. The singles that I wanted to hear were simply punctuating the album with a bit of joy, stopping it from freezing over completely. When you reach "Nil", the final (instrumental) track of the album, you can feel the tension ease from your shoulders and the feeling come back into your toes. So I wasn't that impressed. Of course, I learned to love it. As I did so, I found that a lot of the tracks had more energy and positivity too like "Hanging Around" with its rocky guitar solo and "Higher" with the lyrics we'll make it out of here, oh yeah. The singles are an important part of the album, but they're not everything that the Cardigans are about.

One in particular remains cold, the opening track of the album. It has sound effects of swirling winds and Nina's high wailing voice over deep bass chords singing never lose your grip / don't trip / don't fall / you'll lose it all / the sweetest way to die. But this is one of the most beautiful songs they have ever done, just because it is so chilling. This is where your sanity gives in / and the love begins - you're insane, you're going to die, but in this twisted world, that's the place to find true love.

"Best of the Cardigans" (CD1 in the 2CD version) contains all the singles, but even in that "My Favourite Game" and "Erase/Rewind"-style songs are a small minority. In their review, digitalspy says
Ranging from the sunshine pop of their early 90's releases to the brooding beauty of 2005's Super Extra Gravity, it features a kaleidoscope of musical styles... of the most underrated bands of the last 15 years

Quite right!

Advice #21

Don't look over your shoulder too much.

Or if you do, switch shoulders from time to time to avoid straining your neck and back

Wednesday, 5 March 2008

At last

Since the HMV e-mail telling me that my CD, Best of the Cardigans, is on the way, I have been sick for 3 days out of 7. Maybe there's a link, maybe there isn't, who can say? But it arrived a few minutes ago, and it has certainly cheered me up! Being sick is very stressful as well as being boring. I'm only half-way through listening through CD 1, but it's pretty good! Yay

Monday, 3 March 2008

Self-healing and thermoreversible rubber from supramolecular assembly

That is the title of the Nature article (Nature 451, 977-980 (21 February 2008)) that I wrote about here. At the time I was complaining about the way this BBC article had described the science involved.

So I had a look at the original Nature article, and agree that it is a wonderful and novel substance, so BBC picked up on a good thing. Let me explain it as I understand it. I hope I'm not too far wrong in this, please correct me if I am.

A normal rubber consists of longs chains of atoms, held together by so-called cross-links. The chains like to be coiled up, but if you pull on them, they can uncoil, so the material stretches. If you let go, it will go back, simply because it prefers to be in its coiled-up state*. Since the chains are cross-linked together, it remembers better than other materials how it was before, so it is more elastic than normal materials. Without the cross-links, it would be a plastic, which does not remember its shape as well.

If you cut a rubber, you break some of the bonds. These are covalent bonds, bonds that have strength because they share electrons. Once a covalent bond is broken, one half of the chain takes more electrons than the other, so this half is negatively charged and the other half is positively charged. Positive and negative charges cancel out at the drop of a hat, and they get rid of their charge as quickly as possible. They might grab a gas molecule from the air or react with another part of the rubber, so in a tiny fraction of a second, the loose ends have been tied up and the cut has sealed over. After it has closed up, it's stable and happy, and will not react again. So when you bring the other bit of the rubber back, it will not go back together, even if you do it as quickly as you can posibly imagine.

This rubber is different, because it is made of short molecules, that are all held together by hydrogen bonds. Hydrogen bonds hold the structure together, but they are not quite as strong as covalent bonds. Just like a normal rubber, the end effect is that a network of bonds is created, where segments can stretch and coil up. So this is still a rubber in terms of how it acts normally. The benefit is that a broken hydrogen bond does not leave positive and negative charges. It will tend to attract molecules to tie up the loose ends, but this is not a quick process. This gives you time to put the rubber back together. Slight movement (diffusion) of the chain ends allow the molecules to line up and bonds back together, so that the material heals and the seal is as good as the original rubber if you give it long enough.

There are polymers (materials that come in long chains of atoms) that can re-heal by diffusion already. These chains do not have cross-links, so they are not so rubbery. To heal themselves, the chains just wriggle together until they are knotted together. That works pretty well, entanglements are the way that loads of polymers hold themselves together anyway. But a material like that is able to flow like honey or jelly (two really good foods)**, so it is not a real rubber.

So the material that they have created is unique and special, in being a useful rubber and being able to heal itself. I'm sure there will be lots of places where it can be used, although the authors do not suggest any themselves (they are more interested in the science, as I am too). The same issue of Nature also contained the comment from Justin Mynar and Takuzo Aida “The potential applications are manifold. Tears in clothes that effectively stitch themselves together, long-lasting coatings and paints for houses and cars, and to take one example on the medical front, self-repairing artificial bones and cartilage.” To me, the possibilities seem endless, and given that it is cheap and easy to make, and easy to degrade (so it can be disposed of environmentally), I think we will see a lot of this in the future.

If this article did not make sense, try Physics World. The Times also enjoyed thinking up uses for it.

* it's all about entropy - coiled up structures have a higher disorder so they are preferred, it's a law of physics
**depending on how liquid it is, people talk about creep or viscosity when they talk about a material flowing (under its own weight or otherwise)

Saturday, 1 March 2008

Advice #20

Don't get really really drunk like I did yesterday. I haven't done it that bad in a couple of years at least. I have forgotten portions of the evening and everyone who saw me seems to have something to say on the matter. I've had e-mails about it and threats from my housemates to tell me what kind of things I got up to. And this morning in the lab has been horribly unpleasant, I have a pounding headache and a recurring desire to dash to the toilet.

So yeah, just don't