There’s been a recent lull in the flurry of posts here on the NGN students blog. That’s not to say we’re not all working hard, just that there haven’t been any really exciting trips to share. PhD work comes with an ebb and flow of activity, particularly where external entities have an influence on the progression of your work.
As a group, we’ve all started jumping through the necessary hoops for our Doctoral Development Programme portfolios. Essentially continuing professional development but for students, we now have to cover this as part of our registration as PhD students with Sheffield despite having been here and working for nine months. This has mainly included attending a few lectures on general items like time management as well as signing up for taught modules. Personally, I’m taking standard and advanced electron microscopy, x-ray diffraction and advanced ceramics modules. These seem like hindrances to getting on with the projects but the intention is to bolster knowledge and skills in various areas to make future work easier. It’s all about putting in the groundwork. We also attend weekly group meetings where the entire Immobilisation Sciences Lab (our research group) share presentations of their work, either for practice for an upcoming conference or just to update the group on what we actually do with ourselves. Some of us have already shared our work and off the success of my Chernobyl post, I also talked to the group about that trip.
As for my project, I’ve almost commissioned my ammonolysis furnace. I’m hoping to have it fully calibrated and attempted a couple of synthesis reactions by Christmas. In the lab, I’m currently working on making a large number of uranium containing oxides, including a novel approach using melamine, the plastic stuff 1970s kitchen units were made from. Alongside this I’m also working on ammonium cerium fluorides (because high temperature ammonia wasn’t enough and I needed an added fluorine hazard), looking at the progression of the reactions using XRD and SEM techniques. I’m working on what will become the first substantial chapter of my thesis; a literature review of uranium oxynitrides. Mostly this entails translating French journal entries by hand from dusty old annals in the depths of the university library archives but that always makes for a fun afternoon. For future work, I’ve just put in an application to attend the ISIS neutron scattering experimental training course at the Rutherford Appleton Labs, Oxford. The training should be helpful for when I eventually apply for beam time to study the structure of my oxynitrides.
Someone whose had a lot of dealings with beam time recently is Amber, who has been incredibly busy since her last post:
I’ve been getting some training to use the Hot Isostatic Press here in the lab. This method of processing subjects samples to simultaneous high pressure and temperature. I’ll be processing some of my glass and ceramic samples using this equipment which will ensure that the samples are dense and homogeneous. In practise, this means that the nuclear waste immobilised by these samples will have a smaller footprint and therefore potentially reduce the cost of the geological disposal facility.
I’ve also visited the European Synchrotron Radiation Facility in Grenoble, France, to run an experiment on some of my glass samples which involves firing x-rays of a specific energy at the glass. The transmitted x-rays are then measured and can provide information about the atomic structure of the elements within the samples. I was looking specifically at cerium, which is a surrogate for radioactive actinides, which will hopefully be eventually immobilised using the glass.
At the minute, I’m preparing to present my results at my first conference which is the Indo UK Civil Nuclear Conference. It will be here at Halifax Hall in Sheffield in December so I’m collecting and analysing as much characterisation data as possible to make the presentation as informative as I can!
Sheffield’s other Sarah shared this update:
Having got to grips with how to make the correct cement blends and undertake analysis to understand what is happening with the chemistry and microstructure of my unirradiated materials, I am now studying what effects gamma radiation has on them. My first batch of test samples received a dose of 7MGy (just over half the expected lifetime dose for intermediate level wasteforms – which are cement based) and I am currently in the midst of characterisation on these; I have four different types of cement in total, each with a control specimen which means plenty of lab time for me.
I am using several techniques to look at what minerals have formed, whether there are elemental differences in these, and if the proportions of these alter due to radiation. To look at the microstructure of the samples I’m going to be using a scanning electron microscope to see if there are any differences that might influence the material properties – and will also be looking at the material properties to follow up on this!
This work is ongoing and I have further samples that are still undergoing gamma irradiation so I can investigate the effects of higher doses. I am also starting to plan how I can investigate the effects of alpha radiation on the same cement blends, which is slightly more convoluted to organise in terms of just about everything imaginable. That must mean it’s going to be interesting though, surely….
Joe, in his typical fashion wants to share of his project work so far “…if you gaze long into an abyss, the abyss also gazes into you”. In terms of actual work, he recently presented a summary of his endeavours to his industrial supervisors and partners at Sellafield Ltd, which he reports went quite well. Back in Sheffield, he’s hoping to help out with a large inter-department faculty challenge, which will see him acting as a facilitator/demonstrator/teacher for groups of undergraduate engineering students.
So that’s where we all stand at the moment regarding our PhD work. Not a terribly exciting blog post but then a PhD isn’t all about the trips abroad, there’s actual work to be done too!