Sponsored PhD Scholarship to study Multifunctional Structures

We have a vacancy for a PhD candidate interested in studying multifunctional structures, its design, materials, manufacturing, and performance.

You can find more info here.

Deadline for applications: 19th Feb 2021.

The surface properties of Ti-Nb-Sn alloys

The physico-chemical characterisation of Ti-Nb-Sn alloys surfaces and their osteogenic properties

This is a study motivated by the need to benchmark titanium alloys that are being developed for bioengineering applications and implants against c.p. Ti, traditionally used as the material of choice.

The results will be of interest to those interested in novel Ti alloys for new manufacturing methods (such as 3D printing), a very hot topic at present that marries surface engineering and manufacturing.

Ti alloys design and manufacture are heavily investigated due to their high tunability of mechanical properties, which allows patient-specific and/or anatomical location customisation. This is due to the alloy bulk properties. But the surface of these alloys typically attracts less attention. However, this is equally important in biological applications since this interface is the first environment the cells see and their interaction with it seals the implant’s fate, i.e. long-term anchoring if successful, rejection and infection if not.

This study takes a systematic approach to the study of the factors affecting cell behaviour on a surface, which lacks in current reports. Our results show that although all alloys are non-cytotoxic, Nb element hinders osteoblast maturation, and that the ternary Ti-Nb-Sn alloy, possessing the most favourable combination of bulk mechanical properties, is also a strong contender for bioengineering application given its TiO₂-rich composition, high wettability and negative surface z potential.

The published work can be found here and it is open access.

“No two snowflakes are the same”

One of the people I most admire for the colourful of his personality and elegance and beauty of his work, is Wilson A. Bentley (1865-1931). This gentleman studies the formation of snowflakes under varied conditions of temperature, pressure and relative humidity.

With rather low-tech scientific apparatus (i.e. a simple microscope and rudimentary equipment to control temperature, pressure and % humidity), he created hundreds, if not thousands, of snow crystals. He coined the sentence “no two snowflakes are the same”.

It is snowing heavily in Edinburgh city centre as I write this. It is not that all the different snowflakes that I can see falling from the sky are all absolutely unique and different. His claim mean that, under specific atmospheric and physical conditions (i.e. T, P, %hum, altitude, etc), one and only one type of snow crystal will form, and then fall onto the ground.

These image that I am posting are original photographs taken by Bentley himself from his microscope. The crispness of the images is breathtaking and the beauty of the fractals extraordinary. Enjoy!

For example, when snowflakes crystallises with the shape of a tube or a needle, fall to the ground and form a layer of snow on a mountain, that layer may be the precursor in the formation of avalanches.

Bentley’s pioneer work has helped geophysicists and engineers understand ice formations and how to prevent catastrophes. However, there are many questions still unsolved! Snowflakes grow as thin plates, but if the temperature varies only a few degrees, they evolve into long thin crystals. No one knows why.

This last image belongs to a collection from SnowCrystals.com and a beautiful classification of the different types of snowflakes can be seen here.