Latest News Archive

Please select Category, Year, and then Month to display items
Previous Archive
18 April 2022 | Story Leonie Bolleurs | Photo Stephen Collett
Prof Ted Kroon
Prof Ted Kroon from the Department of Physics recently delivered his inaugural lecture on the topic What’s the use of a rainbow on the UFS Bloemfontein Campus.

“A rainbow is a natural phenomenon, the result of the refraction and reflection of the sun’s rays in drops of rain. As far as mankind is concerned, it’s a perfectly useless object and won’t make anyone money. Yet the poet who said, My heart leaps up when I behold a rainbow in the sky, only put into word the feeling of wonder and excitement we all have when we see a rainbow.”

“Every day I see a rainbow in my work; I do not need to wait to see one in the sky,” says Prof Ted Kroon, Professor in the Department of Physics at the University of the Free State (UFS), who used this phenomenon to introduce the topic of his inaugural lecture: What’s the use of a rainbow. 

“Far from being only a colourful spectacle with no practical value, rainbows are useful – and lead to useful things,” he believes. 

According to Prof Kroon, one can find examples of real rainbows and rainbow analogies used not only in everyday life, but also in physics. “Besides it being familiar devices in literature, culture, and even marketing, studies of rainbows can yield practical engineering information and may even help us to find new habitable planets,” he says.

Inspired by the many uses of a rainbow

In his lecture, he discussed the basic features of natural rainbows and how they come about. He also explored how the rainbow gives meaning to colour, and how this relates to the temperature of objects. He looked at an array of instances where the rainbow is used; from depicting the life of a star to indicating that we are sick (a thermometer) or when we need to refill a gas cylinder.
Moreover, Prof Kroon pointed out that rainbows are used in computer chips, stress identification, and to transmit internet data through underwater cables of glass fibre. He also referred to how the rainbow was harnessed as an engineering tool to measure refractive index and characterise fine droplet sprays used in industry. 

He continues, “Remarkably, the science developed to understand the natural rainbow can be redirected and applied to the optical properties of metallic nanoparticles, allowing the development of nanotechnology. Knowing how the natural rainbow works and its limitations, better systems have been developed to produce rainbows. Such rainbows have been used to discover new elements and to determine the age of the universe.”

As a member of an international community of phosphor researchers who are privileged to work with rainbows every day, he has used them to study the light-emitting properties of materials doped with bismuth. With this project – an initiative with the African Laser Centre taking place between 2016 and 2021 – he collaborated with the University of Khartoum in Sudan and trained a number of its postgraduate students. “My role included the guidance of students and the measurement and interpretation of the light-emitting properties of the materials. Our research during this time, considering more than a dozen materials, was summarised in 34 scientific publications that contributed to a greater understanding of bismuth ions as light-emitting materials,” he explains. 

Developing new materials, efficient in emitting blue light

He has been developing luminescent materials since 2006, primarily for general lighting (fluorescent tubes and LEDs) and displays (television, computer, and cellphone screens), as well as niche applications in medical and forensic science. 

As part of his current research, he is examining the effect of plasmonic metal nanoparticles on phosphor light emission. He is also exploring materials that absorb infrared light but emit visible light. “For this, I would like to consider the long-term stability of such materials and develop new materials that are more efficient in emitting particularly blue light,” he says. 

Prof Kroon holds a C2 rating from the National Research Foundation and has published more than 150 articles and book chapters, obtaining a Scopus h-index of 26.

News Archive

UFS institute set to contribute to transformation in South Africa
2011-01-23

The UFS launches it's new International Institute for Studies in Race, Reconciliation and Social Justice.
- Photo: Dries and Henco Myburgh

Today (Thursday, 27 January 2011), almost three years after the Reitz affair, the University of the Free State (UFS) is launching its International Institute for Studies in Race, Reconciliation and Social Justice. This international institute will be inaugurated by Archbishop Emeritus Desmond Tutu, Nobel Peace Prize Laureate and Chairperson of the former Truth and Reconciliation Commission, who received an honorary doctorate in Theology from the university earlier today.

According to Mr John Samuel, Interim Director of the institute and former Chief Executive Officer of the Nelson Mandela Foundation, the institute seeks to establish itself as a premier international site for research on race, reconciliation and social justice.

“It is encouraging to see the UFS bringing to the fore such an initiative, which combines a study in race, reconciliation and social justice, all of which are indispensible elements in the process of rebuilding our nation,” said the Deputy President of South Africa, Mr Kgalema Motlanthe, in his message of congratulations to the university.

“I am confident that on the strength of its stature, coupled with its eminent experience as an academic institution, the UFS will further assist our country advance towards a united, non-racial, non-sexism, just and prosperous future.

“I wish the institute well in its arduous but noble task of contributing to the building of a better human society,” he said.

Prof. Jonathan Jansen, Vice-Chancellor and Rector, stated during his official inauguration in 2009 that the university would be an example of a place where reconciliation, forgiveness and social justice would not only be studied, but where it would also be applied in practice. “Students and scholars from across the world will come to the UFS to study the theory and practice about the building of societies across the boundaries of race, as well as religion, gender, disabilities and national origin,” Prof. Jansen said.

The institute is a critical space where engaged scholarship, public discussion, community engagement and teaching are innovatively integrated towards exploring and finding solutions to the complex and challenging work of social transformation in South Africa.

The institute furthermore works towards the realisation of its mission through a multiplicity of approaches and methods, informed by the notion that deep and complex social challenges require courageous and challenging scholarship, supported by innovative organisational forms and institutional arrangements.

Working from the inside to the outside, the institute will firstly serve the needs of the university, its staff and students. Through its research, the institute will endeavour to understand the challenges facing the UFS better, as well as how to address these challenges. For this reason, the concept of the UFS as a “live laboratory” and the use of evidence-based practice remain important for the university.

The institute will also reach out and empower its stakeholder communities through research and ongoing involvement on issues of race, reconciliation and social justice. Furthermore the institution expects to contribute to the creation of national and international networks and dialogue platforms pertaining to race, reconciliation and social justice.

For the first five years, the themes of 1) Values, Faith and Social Justice; 2) Development and Social Cohesion; 3) Teaching and Learning for Social Justice; and 4) Provincial, National, Global Perspectives and Leadership will direct the institute’s work.

The UFS will make a substantial contribution to the pursuit of reconciliation, greater social cohesion and equity in South Africa. The university is thus prepared to continue to engage the difficult, practical and trying work of building a strong, quality institution as it promotes racial healing and addresses the structural imbalances of the past. It is at this nexus that the institute commits to enabling change at the university as well contributing to transformation in South Africa.

Deputy President Kgalema Motlanthe's message of support to the University of the Free State (PDF format)

Media Release
27 January 2011
Issued by: Lacea Loader
Director: Strategic Communication (actg)
Tel: 051 401 2584
Cell: 083 645 2454
E-mail: news@ufs.ac.za

 

 

We use cookies to make interactions with our websites and services easy and meaningful. To better understand how they are used, read more about the UFS cookie policy. By continuing to use this site you are giving us your consent to do this.

Accept