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Researchers at the University of Science and Technology of China have recently introduced a new satellite-based quantum-secure time transfer (QSTT) protocol that could enable more secure communications between different satellites or other technology in space. Their protocol, presented in a paper published in Nature Physics, is based on two-way quantum key distribution in free space, a technique to encrypt communications between different devices.

“Our main idea was to realize quantum-secure time transfer in order to resolve the in practical time–frequency transfer,” Feihu Xu, one of the researchers who carried out the study, told Phys.org.

Quantum key distribution (QKD) is a technique to achieve secure communication that utilize based on the laws of quantum mechanics. Quantum protocols can generate secret security keys based on , enabling more secure data transfer between different devices by spotting attackers who are trying to intercept communications.

Nanoparticle superlattice films that form at the solid-liquid interface are important for mesoscale materials but are challenging to analyze on the onset of formation at a solid-liquid interface. In a new report on Science Advances, E. Cepeda-Perez and a research team in materials, physics and chemistry in Germany studied the early stages of nanoparticle assembly at solid-liquid interfaces using liquid-phase electron microscopy. They observed oleylamine-stabilized gold nanoparticles to spontaneously form thin layers on a silicon nitride membrane window of the liquid enclosure. In the first monolayer, the assembly maintained dense packings of hexagonal symmetry independent of the nonpolar solvent type. The second layer displayed geometries ranging from dense packing in a hexagonal honeycomb structure to quasi-crystalline particle arrangements—based on the dielectric constant of the liquid. The complex structures made of weaker interactions remained preserved, while the surface remained immersed in liquid. By fine-tuning the properties of materials involved in nanoparticle superlattice formation, Cepeda-Perez et al. controlled the three-dimensional (3D) geometry of a superlattice, including quasi-crystals (a new state of matter).

Nanoparticles that are densely packed into two or three dimensions can form regular arrays of nanoparticle superlattices. For example, semiconductor particle superlattices can act as “meta” semiconductors when doped with particles to form new mesoscale materials, while plasmonic particles in dense superlattices can couple to form collective modes with angle-dependent and tunable wavelength responses. Large electric fields can occur between such particles for surface-enhanced Raman spectroscopy. Superlattices can be developed at liquid-liquid, gas-liquid and solid-liquid interfaces, where static and dynamic interactions between particle-substrate, particle-particle and particle-liquid interactions can dictate the structure of superlattices. However, it remains difficult to predict such structures in advance. For example, simulating the assembly of superlattices at multiple stages is not yet possible, with very little in-lab real-space data available for modeling.

A German power firm will launch demonstrations of a one-of-a-kind, triple-threat power generating platform off Iraklio, Greece, later this year.

SINN Power has been testing wave converter modules for five years. Buoys attached to steel frame components generate energy as waves push them up and down. The modular nature of the platform is unique in the industry.

“The has been a key element since we started developing maritime technologies that allow flexibility and a wide variety of applications,” according to SINN Power CEO Philipp Sinn. “The floating platform can supply to islands across the world 
 and contribute to the worldwide implementation of offshore wind farms.”

A group of scientists from NUST MISIS developed a ceramic material with the highest melting point among currently known compounds. Due to the unique combination of physical, mechanical and thermal properties, the material is promising for use in the most heat-loaded components of aircraft, such as nose fairings, jet engines and sharp front edges of wings operating at temperatures above 2000 degrees C. The results are published in Ceramics International.