The various shapes are in contrast with the liquid drops which can splash, spread or bounce upon hitting a surface. Successive drops freeze rapidly upon impact due to the drainage of a small fraction of liquid, literally stacking on top of each other into surprisingly slender structures know as granular towers.
Dripping a mixture of sand and water onto an absorbent surface can lead to striking structures of a wide variety of striking forms. Credit: Image courtesy of Julien Chopin and Arshad Kudrolli
In addition, twisted pagoda dome-like structures result upon increasing the flow rate of the damp granular mixture. Experiments show that the towers are held together because of capillary and friction forces, and the shape of the towers depends on a subtle balance between dripping frequency, density of grains, and impact speed. Besides applications in surface patterning, this tower building technique may be a new and easy way to probe the flow properties of dense granular suspensions by observing the shapes of the towers they produce.Peering Out from Under an Invisibility Cloak
Most invisibility cloak designs have one serious drawback - they make it impossible for anyone hiding under the cloak to see what's going on in the outside world. Researchers have now come up with an approach that, in theory, should allow us to make cloaks that allow you to peek out while remaining entirely hidden. In effect, they propose making a tiny tear in the cloak, and then stitching the hole with a two types of materials chosen to effectively cancel each other out when seen from the outside, while still allowing light to enter. Although the cloak design currently exists only on paper, it theoretically ensures that aspiring Harry Potters remain entirely undetectable while keeping an eye on the Voldemorts and Snapes all around them.
James Riordon | EurekAlert!
Astronomers find unexpected, dust-obscured star formation in distant galaxy
24.03.2017 | University of Massachusetts at Amherst
Gravitational wave kicks monster black hole out of galactic core
24.03.2017 | NASA/Goddard Space Flight Center
Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.
The results will be published on March 22 in the journal „Astronomy & Astrophysics“.
Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...
Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.
Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...
In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...
Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to simulate these confined natural conditions in artificial vesicles for the first time. As reported in the academic journal Small, the results are offering better insight into the development of nanoreactors and artificial organelles.
Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to...
20.03.2017 | Event News
14.03.2017 | Event News
07.03.2017 | Event News
24.03.2017 | Materials Sciences
24.03.2017 | Physics and Astronomy
24.03.2017 | Physics and Astronomy