Logic dictates that when you increase the pressure acting on a material, it should compact. So a report from an international team of scientists that they have discovered a crystal formation that expands under pressure is intriguing. The counterintuitive behavior may be exploited to make a crystal sponge for chemical cleanup.
Images: ©Journal of the American Chemical Society/Courtesy BNL
Writing in the December 19 issue of the Journal of the American Chemical Society, the researchers describe the behavior of natrolite, a type of zeolite, under increasing pressure. Zeolites are solids characterized by a three-dimensional structure containing regularly spaced pores within the molecular framework of atoms that includes aluminum, silicon and oxygen (see top image). When the scientists subjected natrolite to pressures up to 50,000 times the normal atmospheric pressure between two diamonds, the material initially compressed, as expected. But when the pressure ranged between eight and 15 thousand times atmospheric pressure, the crystal expanded (bottom image). "This is not supposed to happen," co-author Thomas Vogt of Brookhaven National Laboratory says. "Normally, when you squeeze something, its supposed to get smaller. This stuff gets bigger." As the pressure increased, the material compressed further.
An X-ray analysis suggests that the material expanded because extra water molecules were squeezed into the pores within the natrolite. Terming the unusual property pressure-induced expansion, the team suggests that the material may be used to mop up chemical or radioactive pollutants. "When you increase the pressure and the material gets bigger, the pores get bigger, too," co-author Joseph Hriljac of the University of Birmingham explains. If pollutant molecules enter the structure, he says, "when you release the pressure, the pore would get smaller and trap the pollutants inside."
Sarah Graham | Scientific American
A new tool for discovering nanoporous materials
23.05.2017 | Ecole Polytechnique Fédérale de Lausanne
Did you know that packaging is becoming intelligent through flash systems?
23.05.2017 | Heraeus Noblelight GmbH
Staphylococcus aureus is a feared pathogen (MRSA, multi-resistant S. aureus) due to frequent resistances against many antibiotics, especially in hospital infections. Researchers at the Paul-Ehrlich-Institut have identified immunological processes that prevent a successful immune response directed against the pathogenic agent. The delivery of bacterial proteins with RNA adjuvant or messenger RNA (mRNA) into immune cells allows the re-direction of the immune response towards an active defense against S. aureus. This could be of significant importance for the development of an effective vaccine. PLOS Pathogens has published these research results online on 25 May 2017.
Staphylococcus aureus (S. aureus) is a bacterium that colonizes by far more than half of the skin and the mucosa of adults, usually without causing infections....
Physicists from the University of Würzburg are capable of generating identical looking single light particles at the push of a button. Two new studies now demonstrate the potential this method holds.
The quantum computer has fuelled the imagination of scientists for decades: It is based on fundamentally different phenomena than a conventional computer....
An international team of physicists has monitored the scattering behaviour of electrons in a non-conducting material in real-time. Their insights could be beneficial for radiotherapy.
We can refer to electrons in non-conducting materials as ‘sluggish’. Typically, they remain fixed in a location, deep inside an atomic composite. It is hence...
Two-dimensional magnetic structures are regarded as a promising material for new types of data storage, since the magnetic properties of individual molecular building blocks can be investigated and modified. For the first time, researchers have now produced a wafer-thin ferrimagnet, in which molecules with different magnetic centers arrange themselves on a gold surface to form a checkerboard pattern. Scientists at the Swiss Nanoscience Institute at the University of Basel and the Paul Scherrer Institute published their findings in the journal Nature Communications.
Ferrimagnets are composed of two centers which are magnetized at different strengths and point in opposing directions. Two-dimensional, quasi-flat ferrimagnets...
An Australian-Chinese research team has created the world's thinnest hologram, paving the way towards the integration of 3D holography into everyday...
24.05.2017 | Event News
23.05.2017 | Event News
22.05.2017 | Event News
26.05.2017 | Life Sciences
26.05.2017 | Life Sciences
26.05.2017 | Physics and Astronomy