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.

Foiling the Attraction

Hello,

The magnet 'being put to bed' in aluminum
foil. This weakens the field, but prevents chips
of magnet being lost.

There are some days in science when you get a lot of highly scientific work done. There are others where you get on the bus at the end of the day and say to your friends:

"I spent all day searching the internet for the plastic body of a railway engine."

That was Wednesday's task. It was a little trying, if just because to be held up by such a trivial-seeming task is a little irksome, but 100% necessary - after all, what's a superconducting train track without a good train. The limitations were that the body had to be LIGHT, NON-MAGNETIC and the RIGHT SIZE. You'd be amazed how many toy shops I rang around.

By Thursday morning, though, this was sorted and I began to fill capillaries with the salts used in the synthesis, in preparation for beamtime on Monday; it's a trial time for next weekend. 

However, I was interrupted as I was given safety training for the beamline rooms. You remember the quote I gave from my supervisor at the beginning? The rooms which receive beam, known as hutches, have to be searched for people (and bodies) before the beam is switched off. Pretty serious stuff, given the consequences if anyone is missed. To avoid cutting corners, there are searching buttons which have to be pressed around the beamline rooms.

The magnets can then be positioned on a piece of track. Care has to be taken
though - they snap together with a surprising amount of force.

Friday began me watching a gas cell experiment being prepared; this is similar to what I was hoping to do next week, so the experience was a good indication of the work that goes into it. I then went back to my capillaries so there would be something to do the work on.

That all done, my afternoon was spent re-wrapping the magnets in foil; previously, they wouldn't lie flat, unbalancing the superconductors. I also checked the magnetic field around the track, since at the centre, the magnets can reach up to 160 mT (5 mT is considered strong). Luckily, the strength is very short range, so I was able to use my phone to take picture without risk of scrambling it.

Type soon!

PS. Halfway through my placement now! And things starting the pull together.

Beamtime!

Hello

I start by saying I hope to get my camera into a lab soon. But the past few days, I've been rather busy as I went...

From hot to cold these past few days. It started Friday, when I has not one but two furnaces heating away as I worked on another batch of capillaries. Having made:

The tablets go from a clay colour to black when heated

•  pelleted and pelleted-halfway-through-heating (phth as I will now call it... 'cos I'm lazy) superconductor in air
•  a unpelleted and phth superconductor with a low flow of oxygen (and the furnace did switch off and I did jump for joy)

  the final combination was pelleted in oxygen and unpelleted in air. Since the latter didn't required oxygen, I used the box furnaces instead.

This wouldn't have been so bad if I hadn't been making more capillaries from samples of the last four pellets in the room next door. Phew! And for the mathematician who likes to have a scoreboard:

Capillary 5  Ros 10

I also made a capillary of the salts mixed but not heated because...

Monday I had beamtime!

What's more, I froze! A student on a brief bit of work experience has a small project and for it there were three of us grinding up samples to compared usin7g the beam. And my sample needed to be kept cool, so I did it in the fridge. 

I say three of us, since there was also another intern getting a taste of lab life; he's designing software to help with the data collected on our beamline and came to have a look at what we do. Goes to show, there are a lot of people working outside the beamline rooms to get it running smoothly.

The afternoon, we actually placed  14 samples (including my superconductor samples and mixed salts) into the beam in order to get results. The beam hit the sample and we took a diffraction pattern using the detectors that surround the capillaries. The equipment at Diamond is really highly sensitive and so it gave rather wiggly lines, but by the end, I could make out distinct peaks showing a change from the mixed salt to the cooked superconductors.

Overnight, we left the detectors taking periodic scans of the mixed salts being heated and cooled in situ so we look at the phase change. That's right: I'm doing an experiment using a synchrotron.

The beamline has a traffic light warning system. Red means 'No Entry'. And yes, I hope to get a proper photo.

Coming in Tuesday morning, I'd found my capillary had... well... exploded overnight. On the bright side though, most of the measurements had been made by that point and were waiting to be analysed. 

However, the day was rather busy. There were new users setting up, a meeting with a H&S man, who told us about the 5S process of organisation, a beamline safety meeting (extremely important), tidying up in the lab ready for the monthly Health and Safety checks (like I said, extremely important) and capillaries to load of the superconductors made on Friday. 

The data rather feel by the side for the day, but we did establish that the salts would need to be mixed in a quartz capillary to survive the heating. 

Last job of the day was to put on a new superconductor to cook. I feel I'm becoming quite  chef.

And the final capillary count (inc. the colder attempts):

Capillary 9  Ros 13

 Still winning.

Type soon!

Picture from Clipart.

Capillary vs. Me & a Toothbrush

Hello,

Allow me to introduce mt partner in crime this post...

The Toothbrush

More specifically, an electric toothbrush.

You probably want some explanation for this. Well, I've started in the lab.

Around the beamlines, there are a number of labs, dealing with the experiments and preparation for the beamline work. This includes a fume cupboard, a vacuum chamber, several furnaces, a scanning electron microscope... amongst lots of other things.

Two things I was being taught to use fresh of Monday morning was the  

1. Raman spectroscopy In this, molecular vibrations (known as phonons) interacts with photons (little packets of light) from a laser. The photons scatter inelastically; often photons can be absorbed by the sample and re-emitted at a different energy. This shift in energy can be described as a 'fingerprint' of a particular type of molecule. This information can tell us a lot about the bonds and atoms in a molecule.
2. IR machine performs InfraRed (sic) spectroscopy. It can measure the interactions of a sample with IR light. 

The lovely PostDoc Research Assistant was giving me some tuition in how to use the Raman Spectroscopy. I quickly learnt the hardest thing was to get the machine to focus, but as we were going along, she realised she could use the laser to help pick out a general range before using the light to refine the image before readings were taken. This done, we decided to calibrate the machine using a slide of silicon. One problem: it didn't seem to work.

Never mind. We moved onto the IR machine. This threw up its error message straight away. Given the complexity of the machine, we immediately called another beamline scientist. He poked around for quite a while before declaring that an IT 'expert' had changed something (I think it was the computer) and so the optics card had gone and the software needed to be reinstalled.

This did have a silver lining though. We realised that the reason that the Raman wasn't working was because we'd forgotten to pull up a lever to allow the laser to enter. Whoops!

Lesson learnt though, and I'm glad I learnt it earlier.

Over lunch, I met the new placement students starting. It was nice to hear the other projects and sit in the Sun for a bit - again Didcot has the nice weather.


The afternoon, I went down to the lab with my supervisor and she showed me how to load a capillary (a thin tube of borosilicate or quartz with a funnel at one end - I've tried drawing it... I'll let you try). My beamline specialised in powder diffraction experiments, where fine powders of materials are placed in the beam and the way they interact with the light in studied. The capillaries hold these samples.

To give it a go, I start grinding some Copper Nitrate, a salt I'm using for the superconductor, using a pestle and mortar. About halfway through, we noticed it was getting damp, which causes clumps. I soldiered on though and began to place it in a 0.5mm diameter capillary.

Now, behold the toothbrush!

The vibrational power from it shakes the powder down, settling it at the bottom. Or so it should. Being damp, this didn't happen and I ended up breaking the capillary instead.

Capillary 1  Ros 0

Tuesday and I spent the morning reviewing research on Liquid Nitrogen safety (yes, this included making warning posters and I now know why I did so much poster making at Secondary school), heating YBCO (my superconductor) and phase diagrams on YBCO. My conclusion: there's a lot of research about YBCO in really odd situations, but it's quite hard to find the basics sometimes.

Then, I went down into the lab. And I got exciting news! Given 2 of my materials absorb water from the air like crazy,  I get to use the vacuum chamber to prepare samples of them to give my grinding time.

However, for the afternoon, I started preparing a 0.1 to fit inside a 0.3 mm capillary in order to test a glitter substance of which there are limited amounts. It took a while, but I found a pair which would fit.

Capillary 1  Ros 1

To get practice loading first though, I began loading a 0.7 mm Silicon sample. These are used to calibrate the beamline too, so any which are around will be used. With this is mind, I decided to take my time, teasing the Si down with the toothbrush, using an actual blowtorch to cut the funnel off and carefully gluing it into the capillary holder (it appears superglue really is super enough to be used in the beamline). Then, ever so gently, having spent over an hour preparing it, I screwed the holder into the capillary stand to store. The result:

Capillary 2  Ros 1

On Wednesday, I had a nosey into the beamline as Users were coming in today. What I found was people trying to work on fixing a problem (they occasionally happen, even in a synchrotron) and another beamline caused the beam to be switched off briefly.

I started practicing loading more Si 0.7 mm capillaries. This time, I was more careful and began carefully packing the Si into the tube and using the almighty toothbrush. For Si, it should be quite tightly packed, so I soent a while getting it neatly even.

Capillary 3  Ros 1

 Starting again. By 11.40 though,

Capillary 3  Ros 2

HA!

I then started on the glitter, but just as I finished loading it in, my supervisor appeared.

"Did you grind it?"

I managed to get most of it out.

After lunch, I ground it, and spent a while trying get it into the funnel. The mortar though was too heavy and the powder was now dust. Not willing to admit defeat, my supervisor found a pestle and mortar fit for a mouse. Actually, a mouse might find them a little large. They were incredibly adorable, in a way, and reminded me of the bowls in a doll-house.  

Being careful, with the amount of material left, I regounded gently and tried again.

I tried for an hour and a half (most science is fun, I promise!). The issue was the amount of material, as I scraped the mortar clean, even using the stuff on my gloves, to get only 2 mm of sample. My supervisor, though, thought that given we were fitting a 0.1 capillary inside to make it air-tight it should be OK. Was it? Well;

 

Capillary 4  Ros 2

 The manufacturing leaves a ball of glass at the end thicker than the rest. It wouldn't fit to the end.

The last hour I spent in the beamline, whose experiment was up and running. I'm still gathering details on it, as it's running over several days, so I hope to be able to share a proper explanation at some point.

In terms of Me vs. the capillaries, well...

TBC

PS. Talking to another intern at the end of the day: he also used the toothbrush trick. See, it's a valid scientific method.

   (PPS. All pictures from clipart)