The flow of soap solutions through fibres is of great importance for the final result of the washing process. This is one of the conclusions from the research project of Annemoon Timmerman. She will defend her thesis on Monday 22 April at TU Delft. With this conclusion she supports a theory that was disbelieved for years by experts in the field. Timmerman: “I have now experimentally proven why the laundry is actually clean after less than half an hour of washing. Up to now, that was a mystery.” The research was funded by TNO-Cleaning Technologies.
In the washing of clothes, four factors are important: chemistry (the soap), mechanical action (the stretching of the fibre by the washing machine), temperature and time. Timmerman: “Using these four factors, improvements have been made in the washing process in recent times. But despite the centuries of practical knowledge on the subject, it has actually always remained a mystery why it is that laundry is actually clean in a relatively short time.”
So how does the washing process work? Periodic mechanical forces are exerted on the fibres. This causes tiny flows in and out of the pores in the fibres. Timmerman: “For a long time it was thought that these flows of soap solution had nothing to do with the cleaning of the laundry. It was thought that diffusion allowed the soap to reach the dirt.” Diffusion is the process in which soap is drawn through the outer layer of the fibre, reaching the dirt. With the help of literature studies and experiments, the Delft researcher determined that there were definitely flows through the pores of fibres as well as diffusion. Timmerman: “There is a convection flow through the fibre with moving layers of soap molecules along the pore walls that loosen the dirt particles from within the fibre.” The clothing is cleaned from the inside out. This was never believed in the industry. “Convection along the pore wall? Impossible.” Timmerman’s findings also explain why the actual washing process only takes about ten minutes. “If it were to take place through only diffusion, it would take hours,” says Timmerman. “And we are all witnesses to the fact that that is not the case.”
Maarten van der Sanden | alphagalileo
Fighting myocardial infarction with nanoparticle tandems
04.12.2017 | Rheinische Friedrich-Wilhelms-Universität Bonn
Virtual Reality for Bacteria
01.12.2017 | Institute of Science and Technology Austria
Researchers have developed a water cloaking concept based on electromagnetic forces that could eliminate an object's wake, greatly reducing its drag while...
Tiny pores at a cell's entryway act as miniature bouncers, letting in some electrically charged atoms--ions--but blocking others. Operating as exquisitely sensitive filters, these "ion channels" play a critical role in biological functions such as muscle contraction and the firing of brain cells.
To rapidly transport the right ions through the cell membrane, the tiny channels rely on a complex interplay between the ions and surrounding molecules,...
The miniaturization of the current technology of storage media is hindered by fundamental limits of quantum mechanics. A new approach consists in using so-called spin-crossover molecules as the smallest possible storage unit. Similar to normal hard drives, these special molecules can save information via their magnetic state. A research team from Kiel University has now managed to successfully place a new class of spin-crossover molecules onto a surface and to improve the molecule’s storage capacity. The storage density of conventional hard drives could therefore theoretically be increased by more than one hundred fold. The study has been published in the scientific journal Nano Letters.
Over the past few years, the building blocks of storage media have gotten ever smaller. But further miniaturization of the current technology is hindered by...
With innovative experiments, researchers at the Helmholtz-Zentrums Geesthacht and the Technical University Hamburg unravel why tiny metallic structures are extremely strong
Light-weight and simultaneously strong – porous metallic nanomaterials promise interesting applications as, for instance, for future aeroplanes with enhanced...
An interdisciplinary group of researchers interfaced individual bacteria with a computer to build a hybrid bio-digital circuit - Study published in Nature Communications
Scientists at the Institute of Science and Technology Austria (IST Austria) have managed to control the behavior of individual bacteria by connecting them to a...
11.12.2017 | Event News
08.12.2017 | Event News
07.12.2017 | Event News
12.12.2017 | Earth Sciences
12.12.2017 | Power and Electrical Engineering
12.12.2017 | Life Sciences