Researchers discover why tendons are strong as wire ropes
Under the electron microscope: collagen fiber bundle after mineralization with (the bone mineral) calcium phosphate. © Max-Planck-Institut für Kolloid- und Grenzflächenforschung
A team at the Max Planck Institute of Colloids and Interfaces (MPICI) has discovered with help of BESSY II new properties of collagen: During the intercalation of minerals in collagen fibers, a contraction tension is generated that is hundreds of times stronger than muscle strength. The associated changes in the collagen structure were observed using X-ray diffraction at the BESSY II synchrotron in Berlin-Adlershof while mineralization was taking place.
"This universal mechanism of mineralization of organic fiber tissues could be transferred to technical hybrid materials, for example, to achieve high breaking strength there," says Prof. Dr. Dr.h.c. Peter Fratzl, Director at the institute.
The fiber-forming structural protein collagen is found in tendons, skin and bones, among other places. It is also interesting from a medical or biological point of view to understand what happens in the process of mineralization in bones. Many bone diseases are associated with changes in mineral content in bones and thus altered properties.
Read the full press release on the MPIKG website.
- Porous Radical Organic framework improves lithium-sulphur batteriesA team led by Prof. Yan Lu, HZB, and Prof. Arne Thomas, Technical University of Berlin, has developed a material that enhances the capacity and stability of lithium-sulphur batteries. The material is based on polymers that form a framework with open pores (known as radical-cationic covalent organic frameworks or COFs). Catalytically accelerated reactions take place in these pores, firmly trapping polysulphides, which would shorten the battery life. Some of the experimental analyses were conducted at the BAMline at BESSY II.
- Metallic nanocatalysts: what really happens during catalysisUsing a combination of spectromicroscopy at BESSY II and microscopic analyses at DESY's NanoLab, a team has gained new insights into the chemical behaviour of nanocatalysts during catalysis. The nanoparticles consisted of a platinum core with a rhodium shell. This configuration allows a better understanding of structural changes in, for example, rhodium-platinum catalysts for emission control. The results show that under typical catalytic conditions, some of the rhodium in the shell can diffuse into the interior of the nanoparticles. However, most of it remains on the surface and oxidises. This process is strongly dependent on the surface orientation of the nanoparticle facets.
- Shedding light on insulators: how light pulses unfreeze electronsMetal oxides are abundant in nature and central to technologies such as photocatalysis and photovoltaics. Yet, many suffer from poor electrical conduction, caused by strong repulsion between electrons in neighboring metal atoms. Researchers at HZB and partner institutions have shown that light pulses can temporarily weaken these repulsive forces, lowering the energy required for electrons mobility, inducing a metal-like behavior. This discovery offers a new way to manipulate material properties with light, with high potential to more efficient light-based devices.