Chemistry & Physics

MPI of Colloids and Interfaces: New microcontainers delivering medical substances to diseased tissue

Scientists from the Max Planck Institute of Colloids and Interfaces in Golm, Potsdam, have developed an effective drug delivery technique. The researchers use porous calcium carbonate microspheres as templates for the production of hollow three-dimensional balls. These microcontainers can be loaded with medically effective substances. Furtmerore, small signalling molecules can be attached to their surface, with the help of which the spheres can then find their way to diseased tissue.

Picture: Illustration of the production of colloid spheres.
© Dr. X.Yan

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MPI of of Quantum Optics: Artificial diamond for data storage

Credit cards which are completely fraud-proof and passports which cannot be forged: quantum physics could make both of these possible. This is explained by the fact that the quantum mechanical state of a particle, an atomic nucleus, for example, can be neither copied nor read out correctly without additional information which only authorised users of possible cards have. Accordingly, if a credit card were to contain a quantum memory, it would be protected against misuse. Researchers at Harvard University in Cambridge near Boston, the Max Planck Institute of Quantum Optics in Garching, and Caltech in Pasadena have now successfully stored a quantum state in a diamond crystal for more than a second at room temperature. The researchers now work on extending that storage time and improving their method.

Picture: The stuff that quantum memories are made of: an international team of physicists has succeeded, for the first time, in storing a quantum bit in a diamond for longer than one second at room temperature. The researchers did not use a natural diamond like the one shown here, however, neither was it cut. They produced their diamond artificially by depositing carbon containing one hundredth of a percent of the heavy carbon isotope C-13 and a small quantity of nitrogen from the gas phase onto a substrate. The diamond they obtained in this way had an edge length of a few millimetres. Copyrigt: Henrik G. Vogel  / pixelio.de
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Fritz Haber Institute: Improving catalysts

Insights into the process which converts carbon dioxide into methanol could make it possible to recycle greenhouse gas: There is now one less mystery in chemical production plants. For many decades industry has been producing methanol on a large scale from a mixture of carbon dioxide and carbon monoxide, as well as hydrogen. An international team, including chemists from the Fritz Haber Institute of the Max Planck Society in Berlin, has now clarified why the catalyst used in this process – copper and zinc oxide particles and a small portion of aluminium oxide – works so well. They also discovered why this reaction accelerator has to be produced in the tried and tested way. The researchers established that defects in an as yet unknown combination with mixing of copper and zinc oxide at the catalyst’s surface are the reason why the catalysts are so active. These findings could make a contribution to further improving the catalyst, and also help researchers develop catalysts that convert pure carbon dioxide efficiently. These could be used to recycle the greenhouse gas that is produced when fossil fuels burn.

Picture: The first step towards the catalyst is the most important one: Julia Neuendorf and Malte Behrens control how a mixture of copper, zinc and aluminium salts precipitate the precursor for the catalyst of the methanol synthesis in the semi-automatic precipitation reactor. © Norbert Michalke for the MPG
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The world’s smallest magnetic data storage

Scientists from IBM and the German Center for Free-Electron Laser Science (CFEL), a joint venture of the research centre Deutsches Elektronen-Synchrotron DESY in Hamburg, the Max-Planck-Society (MPG) and the University of Hamburg have built the world’s smallest magnetic data storage unit. It uses just twelve atoms per bit, the basic unit of information, and squeezes a whole byte (8 bit) into as few as 96 atoms. A modern hard drive, for comparison, still needs more than half a billion atoms per byte. The team presents the results in the weekly journal “Science“.

Picture: Antiferromagnetic order in an iron atom array revealed by spin-polarized imaging with a scanning tunneling microscope (HighRes). Credit: Sebastian Loth/CFEL

 

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MPI for Intelligent Systems: Development of low friction surfaces

Friction – without it a car’s tyres or the soles of your shoes did not grip the ground, neither wheels nor feet would be able to move forward. On the other hand friction causes the economy enormous losses – the cost of machine parts rubbing against each other as a result of wear, for instance, is estimated to amount to around eight per cent of the German GDP – some 200 billion euros. Researchers from the Max Planck Institute for Intelligent Systems in Stuttgart and the University of Stuttgart arranged an experiment in which microscopically small surfaces rub against each other. This way they observed for the first time how friction takes place on an atomic level and found out why objects with the same structure create more friction when they rub against each other than those with differing structures. The results will could be the basis for the construction of micro- and nano-machines that are as low in friction as possible.

 

Picture: Friction by region – When two microscopic surfaces with the same structure slide over one another, not all particles move at the same time. In fact, the particles in some areas slide (blue spheres), thus distorting their configuration. The other particles (green) stay where they are in the hollows of the surface. © Thomas Bohlein/Ingrid Schofron

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Overestimated potential – Energy from jet stream: sorry, nope!

Researchers at the Max Planck Institute for Biogeochemistry found out:
1. The high winds of the upper atmosphere contain less renewable energy than previously assumed
2. Jet stream energy extraction would cause massive climate change.

Picture: Rotary wind turbines could hang like kites in the upper atmosphere where the jet streams blow. This photomontage shows what they might look like. © Lee Miller

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Finally: No more dirty windscreens thanks to self-cleaning glass

Due to its spherical nanostructure, fluorinated silica coating repels water and oil very effectively: Eyeglasses need never again to be cleaned, and dirty windscreens are a thing of the past! Researchers at the Max Planck Institute for Polymer Research in Mainz and the Technical University Darmstadt are now much closer to achieving this goal. They have used candle soot to produce a transparent superamphiphobic coating made of glass. Oil and water both roll off this coating, leaving absolutely nothing behind. Something that even held true when the researchers damaged the layer with sandblasting. The material owes this property to its nanostructure. Surfaces sealed in this way could find use anywhere where contamination or even a film of water is either harmful or just simply a nuisance.
Picture: A surface from which oil and water simply bounce off: The superamphiphobic coating is not even wet by the low-viscosity oil hexadecane, which would spread out even on a non-stick coating. Therefore, a drop of the liquid first bounces up off the surface before coming to rest on it as an almost perfect sphere. The superamphiphobic properties arise from the sponge-like glass structure that researchers at the Max Planck Institute for Polymer Research have developed. © Science / Xu Deng – MPI for Polymer Research

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MPI for Solar System Research: Hartley 2 – first comet with water similar to that on earth

Scientists from the Max Planck Institute for Solar System Research (MPS) in Germany publish their results, which they obtained  at ESA’s space observatory Herschel. The Observations of the comet Hartley 2 have revealed the first comet with water similar to that on our home planet. The results lead to the question “did  comets bring water to Earth?”. Current theories say that less than ten percent of Earth’s water originate from comets. However, the new results imply, that comets may have played a much more important role.

The water of comet 103P/Hartley 2 is characterized by a similar deuterium-to-hydrogen ratio as the water on Earth. This image of the comet was taken on November 4th, 2010, by NASAs EPOXI spacecraft. © NASA/JPL-Caltech/UMD Continue reading

MPI for Chemistry: Determination of city pollution levels from space

Pollution produced by cars and busses in megacities contribute to the damage of the resident´s health. A new method from researchers from the Max Planck Institute of Chemistry, the University of Heidelberg and the Royal Netherlands Meteorological Institute De Bilt now allows for more accurate measurements of the pollution levels using the satellite instrument OMI, which measures the nitrogen oxides pollution, and a mathematical trick.

 

Picture: From pollution to emissions – The left graph shows, how nitrogen dioxide is distributed on average over the Middle East for calm. Red indicates high pollution levels, white low. The right graph shows the distribution of nitrogen dioxide around Riyadh for different wind directions and calm (centre). The distinct downwind plumes allow scientists to determine how quickly the pollutant disappears from the atmosphere and thus how large the emitted amounts in Riyadh are. © Science/MPI for Chemistry Continue reading