Wednesday, August 31, 2011

31/8/11 - Fireworks

Midway through our trip to France was a French bank holiday, this was celebrated by one of the best firework displays I have ever seen (and set to The Lion King music of all things...)

I was hoping to find a video of it but I can't see any lurking on t'interweb so you'll just have to take my word for it, it was awesome!

Anyway, while everyone else was "oooh"ing and "aaah"ing (this seems to be universal between English, French, Dutch and whoever else was on the beach too) I couldn't help but let my mind wander into the chemistry of fireworks. It struck me how little I really know about how they actually work so I decided some research was in order once I was back home and online!

I already knew that the different were colours were down to which metal salts where used (although I wouldn't have been able to tell you which does which!). Didn't need the internet for that bit as we've covered it numerous times before thanks to flame tests:
Red: Strontium and Lithium
Orange: Calcium
Yellow: Sodium
Green: Barium
Blue: Copper
Purple: A combination of strontium and copper)
Silver: Magnesium / Aluminium / Titanium

This is useful to know, but what I was really interested in was finding out the mechanics of it - so how they get the different patterns, what causes the delayed explosions in some of them, etc?

The answers turned out to be a lot more simple that I was expecting - the short answer is that some very clever pyrotechnic experts design the composition of a firework so that it can do whatever they want!

The first thing that must happen is universal amongst fireworks and is relatively simple - a form of gunpowder is ignited by a fuse, the highly exothermic reaction that follows provides the power to send the firework into the air, this is achieved by trapping the gas produced and allowing sufficient pressure to build up.

A second fuse is lit at the same time as the first, however this one burns much more slowly and will only ignite the packed chemicals (giving the pretty colours and patterns) some time after the firework is in the air. This has to be precisely timed and will occur when the firework is at its peak height, as well as causing a colourful explosion other chemicals will be present to give the big bang.

The explosions are as a result of a variety of oxidation and reduction reactions, nitrates being the most commonly used oxidising agents, as well as perchlorates.

I am now going to have to resist the urge to see how easy getting hold of some of these chemicals might be...home made fireworks anyone?

Saw this on youtube, not real but thought it showed the likely outcome if I started playing!


This is to be the first of possibly multiple entries today to make up for my lack general lack of blogging recently. There'll be at least 2 anyway!

First things first - what have I been doing thats kept me so busy in last few weeks?

First off was the 2 weeks in France, it was a great holiday; I'm British so I'll start by mentioning the weather - couldn't have been much more perfect for me; we had a couple of rainy days which gave us an excuse to go to the touristy attractions rather than sitting on the beach and the rest of the time it was lovely and sunny but without being too hot (I'm not a hot weather person!).

I was still all taped up after my operation and feeling rather sore so nothing too strenuous for me, in the 10 days we were actually there I managed to read 8 books (yes, all proper books with lots of pages) which I was quite pleased with, although that does mean that I don't have any more new books left to read! I did manage to play some beach tennis with my brother as playing proper tennis didn't go well for me right handed!

Holiday memories are already fading but things that stick in my mind are the ridiculously busy supermarket and the lack of any restaurants selling any food we liked (no we don't like mussels!). I went in the sea once (just up to my waist as I couldn't really swim!), being the atlantic it was pretty chilly but I couldn't help sitting on the beach the rest of the time wishing I could be having fun in the "surf"!

Since I've been home I've been busy with various hospital updates (more on that in a minute) and have had lots of days at work too. My extra days at work paid for todays trip to Milton Keynes, I was very excited about it as I came back with the MacBook Pro on which I am writing this blog. The buying experience was mostly pleasurable - the salesman was rather pleasing on the eye and they had extra discounts which meant it cost me less than I was anticipating, and they were pretty quick about it too which makes a change. Less happy about being told by the guy that looking at my scar made him feel ill (I do hope he was joking!). Now have to get to grips with Lion, can't believe how different it is so might take some getting used to!

OK, onto the arm, I've been doing my various physio exercises almost every 2 hours and thankfully can now just about straighten my elbow, so at least I know the scar bit of it is healing OK. I'm very much running out of optimism that the nerves are going to fix themselves as I'm getting beyond the window where this normally happens and there is still no improvement in hand and wrist function (hence the shiny, new laptop so that I can take notes in lectures!) . Have yet more appointments coming up but the current opinion from the consultant is that I'm going to benefit from tendon transfer surgery (doesn't that sound fun?) so that at least I can get my thumb working again. I've opted to wait and see how things pan out as uni is rapidly approaching (not that I really fancy going back!), in the mean time the hand therapists (who are far too smiley!) are building me a "bionic" hand, its not technically bionic as its just metal rods and elastic but it'll help move my fingers so I'm not complaining!

Next week is my final appointment with the consultant before uni, more hand therapy and a disability assessment at uni so hopefully they can come up with a viable solution for labs and whatnot! As far as my deep and inner emotions and thoughts go, I don't really know how I feel about it yet. Its started to sink in that this might just be a "big thing" but I'm still smiling. I'm sure the fact that since it all happened I don't enjoy watching programs like Casualty and Holby City means something, but I'm not sure what yet...

Friday, August 5, 2011


Ok so I've been slacking on blog updates, and this'll be my last post for a while as im off on holiday next week.

A lot has happened with the arm - finally found a consultant who knows what they're doing and after a rather painful nerve test followed by a cancelled surgery slot I had an operation Monday afternoon. I spent 3.5 hours in surgery and was, as expected, feeling pretty rubbish for 24 hours afterwards.

Wednesday was a trip to the hospital to see my consultant and find out what they actually did! Was feeling a lot better by Wednesday morning but still pretty tired and sore. Turns out my main, interosseous nerve was in tact but I was in apparently in quite a mess. They tidied me up and now we play the waiting game to see if there's any permanent damage. Talk of further surgeries to move muscles further down the line depending how it goes - how scary! :(. Currently I'm seeing little improvements all the time, probably because the swelling's disappearing but still have less functionality now than before the op :(

Now have lots of physio exercises to do whilst on holiday and then we can see how all is going. I have plans to get back on my bike after my holiday whatever happens - id like to think working in a bikeshop means I have some of the best brains working on any necessary modifications to the bike! Uni are now vaguely aware of what's going on so if there's still problems in September all should be good :)

In the mean time im very excited about holiday as I didn't get one last year - hoping for lots of sun, sea and relaxation. My only problem is that I can't take pictures with my SLR because it's a 2 handed job!

"See" you when I get back from France!