Category Chemistry/Nanotechnology

Lightning Strike can Reshape a Mineral’s Crystal Structure:

A rock fulgurite revealed that lightning strikes alter quartz's crystal structure on the atomic level.

A rock fulgurite revealed that lightning strikes alter quartz’s crystal structure on the atomic level.

Researchers once believed only meteorites could do so. At a rock outcropping in southern France, a jagged fracture runs along the granite. The surface in and around the crevice is discolored black, as if wet or covered in algae. But the real explanation for the rock’s unusual features is more dramatic: a powerful bolt of lightning.

Using extremely high-resolution microscopy, Prof Gieré et al found that not only had the lightning melted the rock’s surface, resulting in a distinctive black “glaze,” but had transferred enough pressure to deform a thin layer of quartz crystals beneath the surface, resulting in distinct atomic-level structures called shock lamellae...

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Acetic Acid as a Proton Shuttle in Gold Chemistry

Gold compounds can surpass nickel and palladium-based catalysts in common reactions + often demonstrate novel types of reactivity compared to well-established catalysts. This allowed chemists to discover new chemical reactions and predetermined a fascinating boom in gold catalysis that we have observed in the recent years.

Professor Ananikov’s team introduced gold into well-known catalytic system which led to dramatic change of the reactivity and furnished the formation of novel gold-containing complexes. They appeared to be air stable and were isolated in the individual state. A single crystal Xray diffraction study ascertained the existence of a unique structural motif in the molecule, which cannot be explained within a conventional mechanistic framework.

The study used both theoretic...

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NASA’s Curiosity show Silica-rich Mars rocks—might preserve ancient Organics

 

Approaching its 3rd anniversary of Mars landing, the rover has found a target unlike anything it has studied before – bedrock with surprisingly high levels of silica. Silica is a rock-forming compound containing silicon and oxygen, commonly found on Earth as quartz. This area lies just downhill from a geological contact zone the rover has been studying near “Marias Pass” on lower Mount Sharp.

>>Curiosity team decided to back up the rover 151 feet from the geological contact zone to investigate the high-silica target dubbed “Elk.” The decision was made after they analyzed data from 2 instruments, the laser-firing Chemistry & Camera (ChemCam) and Dynamic Albedo of Neutrons (DAN), which show elevated amounts of silicon and hydrogen, respectively...

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Study could Lead to a New Class of Materials for LEDs

Electroluminescence from vertically stacked GaN–Al2O3–MoS2–Al2O3-graphene heterostructures.

Electroluminescence from vertically stacked GaN–Al2O3–MoS2–Al2O3-graphene heterostructures.

1st demo of electroluminescence from multilayer molybdenum disulfide, or MoS2, a discovery that could lead to a new class of materials for making LEDs. In its single-layer form, Mos2 is optically active, meaning that it emits light when electric current is run through it or when it is shot with a nondestructive laser. Multilayer molybdenum disulfide, by contrast, is easier and less expensive to produce, but it is not normally luminescent. In the new study, Duan and Dehui, created the 1st multilayer device that shows strong luminescence when electrical current is passed through it.

“It was rather surprising for us to discover that similar vertical devices made of multilayer MoS2 somehow showed ...

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