Menu

Blog

Page 7380

May 28, 2020

Electron microscopy of nanoparticle superlattice formation at a solid-liquid interface in non-polar liquids

Posted by in categories: chemistry, nanotechnology, particle physics

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.

May 28, 2020

Why Immunity to the Novel Coronavirus Is So Complicated

Posted by in category: biotech/medical

Some immune responses may be enough to make a person impervious to reinfection, but scientists don’t yet know how the human body reacts to this new virus.

May 28, 2020

Gene-editing patents have increased tenfold in just four years. Here’s what the technology could cure

Posted by in categories: biotech/medical, genetics

CRISPR gene-editing trials have taken off—and may hold the key to medical breakthroughs.

[Illustration: Jamie Cullen]

May 28, 2020

A Virus-Hunter Falls Prey to a Virus He Underestimated

Posted by in category: biotech/medical

Peter Piot, 71, one of the giants of Ebola and AIDS research, is still battling a coronavirus infection that hit him “like a bus” in March.

May 27, 2020

What Bill Gates hopes we learn from coronavirus

Posted by in category: biotech/medical

Vox interviewed Bill Gates in 2015 about his fears of a global pandemic. Now that we’re living in that reality, what does he think comes next?

Watch our 2015 interview with Bill Gates here: https://youtu.be/9AEMKudv5p0

Continue reading “What Bill Gates hopes we learn from coronavirus” »

May 27, 2020

Chinese Researchers Disrupt Malware Attack That Infected Thousands of PCs

Posted by in category: cybercrime/malcode

Chinese baidu and qihoo 360 researchers disrupt double gun botnet malware attack that infected thousands of pcs.

May 27, 2020

German firm introducing game-changing solar-wind-wave energy platform

Posted by in categories: energy, sustainability

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.”

May 27, 2020

Scientists develop the most heat-resistant material ever created

Posted by in categories: materials, transportation

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.

May 27, 2020

Mobile Nuclear Microreactor Development: A Military-Civilian Symbiosis

Posted by in categories: computing, military, nuclear energy

EXECUTIVE SUMMARY: The US Department of Defense has been working with American companies for the past year on a project to develop a prototype for a portable nuclear microreactor, a device intended for use by the US military in security scenarios around the world. The US Department of Energy is also involved in the project, with the aim of providing electricity to remote sites that are difficult to link to the grid. The project thus represents a symbiosis between military and civilian technological development.

A symbiotic relationship between military and civilian aspects of technological development gained momentum in the US after the end of WWII. This was particularly visible among applications in the communication, computing, and aerospace fields, but was also present in the field of nuclear technology. Some technology projects were presented as dual-use in order to justify the cost of their development.

One example of nuclear energy symbiosis was the development of nuclear power-generating reactors. By 1956, more than a decade after the destruction of the Japanese cities of Hiroshima and Nagasaki by nuclear bombs, only the UK’s Calder Hall nuclear power plant, which had four reactors each producing 60 MW electricity (MWe), was in operation. However, as of December 2019, 443 nuclear power generators were operating worldwide, with a total output of 395 gigawatts electric (GWe)—an average output of nearly 900 MWe per reactor.

May 27, 2020

Mysterious ‘Fermi Bubbles’ may be the result of black hole indigestion 6 million years ago

Posted by in category: cosmology

Twin shock waves produced by the galaxy’s central black hole could have inflated the gargantuan Fermi Bubbles about 6 million years ago, a new study suggests.