Showing posts with label nitrogen. Show all posts
Showing posts with label nitrogen. Show all posts

Wednesday, 10 September 2014

Demo Days

Hello,

It has been a far colder, more active this week so far, and my last here at Diamond. The weeks have flown by.


Monday was centred around a practice presentation. In the morning, I reviewed my presentation with my supervisor and was able to pick up a few tips to improve it further. By the afternoon, though, I had a mini audience as I gave the talk, this time incorporating a small demonstration along with. I thank all my audience members, who were the staff on the beamline for their attention and suggestions and support when my truck promptly fell apart. I now know not to strap the superconductors on in a hurry.

That afternoon, I also managed to figure out a way of storing the track, at least temporarily. Wrapping the set-up in foil and cardboard allows it to be kept flat and reduce the magnetic field considerably.

Tuesday morning was spent taking on board these suggestions and improving my poster. As mentioned, science posters are a good, visual way to impart information to many people, but they come with the restrictions of space and needing lots of images. Most my time was cutting down sentence size.

The afternoon was a long session with liquid nitrogen and the new superconductors which arrived over the weekend. This allowed me to set up plenty of trials and even attached more superconductors to the train, though in many cases it over-balanced them. However, I gained this footage, for those who've missed my demonstrations. The beeping is my oxygen monitor.


Wednesday started with me setting up the trains again, ready for the real presentation. The whole kit was carried to Diamond House's meeting room and I set it all out on the table. I did manage to catch most the talks, including ones about terahertz radiation to count electron clusters in the beam, steadying a imaging machine and topological insulators (find out more at diamondlifeblog.tumblr.com/post/92147428772)(apologies for bad explanations).

Unfortunately, I missed one talk, setting trains to cool. My presentation seemed to go down well, and I had 4 floating objects which I cycled through in order to let many people see. As mentioned in my speech, people seem to like physical demonstrations.

That afternoon, I was experimenting with bigger trains, along with 2 of the other placement students. They say a picture paints a thousand words so look!


Type soon!
 

Tuesday, 19 August 2014

Let's Hover

Hello,

Well, the beamtime may be over, but it just means the train must progress.

A sad non-levitating train, even if steam is coming from its chimney.
Wednesday morning, first thing, I glued up the engine, stinking out the lab with the glue. Had to leave it in the fume cupboard to dry. However, it was ready for an afternoon of testing which... didn't go so well. Turns out the glue wasn't as much as a problem as the bottom warping upon meeting the cold. It was throwing superconductors everywhere.

I did tape it up (seeing as sellotape seems to be the only reliable thing) and managed to get an engine which didn't leak. And didn't levitate. I now blame its weight. I re-glued it to be left over the weekend.

Thursday and Friday I was on holiday because, well, I was fairly tired by this point. 10 day week and all.

Monday morning, though, I was  back and ready to try again. After a quick meeting with a insertion device scientist (he deals in many magnets), we decided to try stronger magnets and different arrangements. The samarium cobalt magnets were replaced first by neodymium iron boron magnets and then by one of the largest permanent magnets I'd seen. It was about the size of  half a brick.

However, this turned out to be too powerful and couldn't even hover a single superconductor disk (a feat I've managed before. This is due to superconductors having a critical magnetic field. Like the critical temperature, once above this, the superconductor can no longer superconductor; it becomes an expensive black disk. The neodymium magnets did provide lift on the disk... but the magnetic field peaked so dramatically, it was hard to balance the disk at a height of about 10 cm.

So we were back with the samarium cobalt magnets... and a non-levitating train.

So, with a public viewing looming, Tuesday morning I was off to the shops. Yes, that's right, I got to spend 2 hours going around toy shops for trains, cars and skateboards (because hoverboards would be awesome too). And look what I manged Tuesday afternoon:


OH YES!!!
Type soon!

PS. All magnets used are those leftover from the building of the beamline. They help direct the beam and maintain its energy.

PPS. I will hopefully be adding to the picture collection here and on Twitter (@AdamasRos) 

Wednesday, 6 August 2014

Into the Beam Room

Hello,

 
Starting again on Monday and getting into the week with Beamtime. After gaining a diffraction pattern of the last YBCO I made, the morning was spent attaching the capillary furnace, known as the STOIE, in the beamline; you can see pictures of it to the left. This allows the capillary to be heated more accurately and uniformly than the alternative, the hot air blower, meaning we can get nice diffraction patterns of the YBCO salts heating up.

In principle. After a few coding problems, the furnace started glowing at lower temperatures than expected and the whole experiment switched off early as a safety measure. Turned out, the thermocouple inside was rather damaged, so had to be replaced. Meanwhile, I loaded a capillary of platinum (approx. £10 worth before anyone gets too excited) to use as an alignment help later.

Once working, we started aligning a new salt capillary. This one though provided us with a few difficulties and it was while swapping it for another that I accidentally broke a capillary. Whilst becoming a rarer occurrence, I'm pleased to say, this time it did get stuck in the furnace. In the end, we switch stages (the type of stand in front of the beam) and did 'Rapid Access'; these are samples sent in just for a quick scan.
The STOIE surrounded by the giant detectors.

With the upcoming beamtime over the weekend, on Tuesday I started researching a Plan B for the time then. As a scientist, you must always be prepared for not getting what you expected, because half the time, you're trying something which may not work. For this, I was researching reactions and compounds using the Oxides I'm using for the synthesis (Barium Carbonate, Yttrium Oxide and Copper (II) Oxide).

However, there was a break as I went to a skills session of presentations. It is always useful to be able to talk other people through the work you are doing to encourage interest and further research in the subject.




The gas cell capillary enables gases to flow across the sample in situ.
Wednesday got very cold first thing, as I tried to get a train to levitate with the superconductors attached. Trying several ways and butchering it with pliers, I did get slight lift off the rear of the engine briefly, but the liquid nitrogen poured off almost as fast as it was added.

In the afternoon, I practiced preparing a gas cell capillary. This involves wrapping the sample up in quartz wool and sliding it into an open-ended tube held in a stand as shown. Whilst I didn't break many blank capillaries while practicing loading them into the stand, it turns out the putting cotton-wool-like material is harder than it looks (and it looks hard). However, I didn't break anything while doing it, so tomorrow morning, I should be able to go back and try again.



Type soon.

Tuesday, 29 July 2014

A Variety of Skills

Hello,

The SQUID samples require less material and are MUCH
easier to load - not a toothbrush in sight.
By Friday, I was coming to the end of my time with the SQUID, but managed to get some interesting results from my 9th piece... and it's looking good. However, I've discovered that placing a small sample under 1 T can produce some... interesting and lasting effects. Luckily, I shouldn't get near that with my track.

While the final tests on that were on-going, I attended an Public Engagement Workshop; it's always incredibly to spread the word of science and let people know exactly what we scientists get up to. You can judge how I do with this blog.

The afternoon, I loaded an YBCO capillary ready for some possible sneaky beamtime next week (it's so useful to compare results, with the others) and mixed up some salts in case I suddenly need to bake a new sample.

Over the weekend I had a very long night to watch the Didcot cooling towers come down. A historic moment indeed.

Monday was a slow start, mainly because my bus was very late (ah, roadworks). However, I then got into a Skills session on producing a scientific poster, a good, visual way to display scientific research. If you don't like reading complicated papers, maybe try looking over posters instead. It was followed by a talk from Prospect, a Union focused on Science, Technology, Engineering and Mathematical jobs (STEM). It was interesting to see what they thought the current issues facing scientists were.

All doors to the beam rooms have a traffic light
system to show when you can enter. Red is
firmly stay out.
The afternoon, though, I got back to my science as I cracked out the Liquid Nitrogen again to try hovering a superconductor over my track. And I manage it with both a pre-made disk AND the sample I made the end of last week (Yay!). However, they both warm up rather quickly and can't yet support the heavier train.

Things seems to be taking shape by Tuesday, as I tried to finalise the track design and help the train engine retain the coolness. Huge thanks to the Beamline technician, who hollowed out my engine to form a Nitrogen reservoir and attached the superconductor to the bottom. It was a shame that the train still seems to be heavy and the superconductor aren't quite in cold enough yet. Now trying to source a hollow plastic shell of an engine.
 
Also that day, I attended a very good lecture by Professor Bartolini. It was on the Physics of the Accelerator and explained a lot about the purpose of the dipole and quadrupole magnets to focus the beam. It was interesting to hear about some of the inner workings of the beamline that produces the radiation we use.  

Type soon!

Monday, 21 July 2014

Playing with Fi-- Liquid Nitrogen

Hello,

It would seem the temperature isn't about to settle down at any point in the next few days, as I've melted, frozen and melted again over the past week. And people mock when I say I don't know what to wear.

Wednesday was a day of preparation as there is the possibility of more of my samples undergoing x-ray diffraction over the weekend due to a low demand rapid access day (a day for quick sample testing and catch-up for those users who experiments have been blighted by beam problems). This did mean I was stuck in the lab most the day, preparing these samples, as I'm currently up to 7 samples of superconductor. And below you can see the kit I used to make the 8th.
The pestle and mortar used to mixed the salts. Before heating, they must be well grounded together to become a uniform clay-like colour. The white dishes are disposable weighboats used for the Copper Oxide and to the left you can see a toothbrush left over from capillary loading, since the same equipment is used.


Because of this, Thursday started the same and would have appeared to continue the same. This was particularly uncomfortable as the furnaces had not dipped below 200 degrees for over 36 hours by this point. It would seem I was responsible for the heatwave.

However, in the afternoon, my supervisor and the work experience student decided that it would be fun to play... I mean, seriously experiment with liquid nitrogen. So I left the baking lab to clearing ice off petri-dishes.

At first, we just tried to hover a magnet over a pre-made disk, which worked well of course. In some ways, it was inevitable that such high beginnings could not be carried through to my own experimental samples, since I had tried a variety of ways to make them, most which would never work.

Just as I was beginning to worry, though, there was a glimmer of hope as a small black slab I'd made supported a magnet! It wasn't as high as the professionally made piece, but I still call victory.

A view into the furnace, which glows red hot once above approximately 700 degrees. Any closer than that and I'd burn my fingers.
Friday was a day off as I was persuaded to go to London. ... Thankfully, my friend had a pool.

Monday was spent testing my samples with a new piece of kit... the SQUID (Superconducting QUantum Interference Device). This allows me to measure the magnetic moment whilst cooling and heating the samples from as low as 10K (-263 degrees) and varying the magnetic field. This provides a good idea as to whether I have superconducting material, giving a pretty graph to prove it. And do I? Well, early days, but the one superconductor I didn't try on Thursday (no. 8 was cooling still at that time) did look slightly promising... fingers crossed.

Type soon!