Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Solid or liquid - the particle size matters

26.01.2015

Max Planck researchers elucidate how the phase state of aerosol nanoparticles depends on their size

Whether tiny particles in the air, so-called aerosol nanoparticles, are solid or liquid, is of great importance to atmospheric and climate scientists. The phase state determines if and how fast such particles grow into cloud condensation nuclei on which water vapor can condense to form cloud droplets and precipitation.


The particle size of aerosol nanoparticles is as important for the phase state as the chemical composition and temperture. The 2D (left) and 3D (right) phase diagram illustrates this correlation.

Hang Su, MPI for Chemistry

Until recently, however, experimental observations of the solid-liquid phase transitions and humidity-dependent growth of atmospheric aerosol nanoparticles could not be explained by theoretical calculations and model predictions.

Scientists at the Max Planck Institute for Chemistry could now resolve the riddle. "The particle size is more important than we previously thought, "says Yafang Cheng, group leader at the institute in Mainz. "For example, salt particles can become liquid not only by increasing temperature or humidity, but also by reducing the particle size," says the lead author of a recent publication in Nature Communications.

The researchers around Yafang Cheng and Hang Su analyzed high precision measurement data on the hygroscopic growth of sodium chloride and ammonium sulfate nanoparticles exposed to varying relative humidity.

From these growth curves, the researchers calculated the interfacial energies and critical diameters for the solid-liquid phase transitions of the salt nanoparticles. According to similar analyses, the researchers expect that organic aerosol particles commonly occuring in large quantities in the atmosphere are always liquid at room temperature when their diameter is below approximately 20 nanometers.

"Based on our results the particle size should be considered as an additional dimension in the phase diagram of aerosol nanoparticles," says Cheng´s colleague Hang Su. “Our findings are also relevant for other research areas where nanoparticles play a role, including the biomedical and materials sciences.” For example, they may help to determine and control the solubility and concentration of therapeutic or reactive agents in in synthetic nanoparticles for medical or technical applications.

Original publication
Cheng et al., Size dependence of phase transitions in aerosol nanoparticles, Nature Comm., 6, 2015, doi:10.1038/ncomms6923
http://www.nature.com/ncomms/2015/150114/ncomms6923/full/ncomms6923.html

Contact
Dr. Hang Su
Max Planck Institute for Chemistry
Telephone: +49-6131-3057301
E-Mail: h.su@mpic.de

Weitere Informationen:

http://www.mpic.de/en/news/press-information/news/solid-or-liquid-the-particle-s...

Dr. Susanne Benner | Max-Planck-Institut für Chemie

More articles from Life Sciences:

nachricht Discovery of a Key Regulatory Gene in Cardiac Valve Formation
24.05.2017 | Universität Basel

nachricht Carcinogenic soot particles from GDI engines
24.05.2017 | Empa - Eidgenössische Materialprüfungs- und Forschungsanstalt

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: A quantum walk of photons

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....

Im Focus: Turmoil in sluggish electrons’ existence

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...

Im Focus: Wafer-thin Magnetic Materials Developed for Future Quantum Technologies

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...

Im Focus: World's thinnest hologram paves path to new 3-D world

Nano-hologram paves way for integration of 3-D holography into everyday electronics

An Australian-Chinese research team has created the world's thinnest hologram, paving the way towards the integration of 3D holography into everyday...

Im Focus: Using graphene to create quantum bits

In the race to produce a quantum computer, a number of projects are seeking a way to create quantum bits -- or qubits -- that are stable, meaning they are not much affected by changes in their environment. This normally needs highly nonlinear non-dissipative elements capable of functioning at very low temperatures.

In pursuit of this goal, researchers at EPFL's Laboratory of Photonics and Quantum Measurements LPQM (STI/SB), have investigated a nonlinear graphene-based...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Marine Conservation: IASS Contributes to UN Ocean Conference in New York on 5-9 June

24.05.2017 | Event News

AWK Aachen Machine Tool Colloquium 2017: Internet of Production for Agile Enterprises

23.05.2017 | Event News

Dortmund MST Conference presents Individualized Healthcare Solutions with micro and nanotechnology

22.05.2017 | Event News

 
Latest News

Physicists discover mechanism behind granular capillary effect

24.05.2017 | Physics and Astronomy

Measured for the first time: Direction of light waves changed by quantum effect

24.05.2017 | Physics and Astronomy

Marine Conservation: IASS Contributes to UN Ocean Conference in New York on 5-9 June

24.05.2017 | Event News

VideoLinks
B2B-VideoLinks
More VideoLinks >>>