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Minnesota train carrying ethanol derailed, caught fire; evacuations ordered

BNSF said about 22 rail cars carrying mixed freight, including ethanol and corn syrup, derailed at 1:02 a.m. local time Thursday. Four rail cars caught fire, the BNSF said. There are no other hazardous materials on the train and no injuries were reported, the company said.

“BNSF personnel are responding to assess the derailment site and will be working closely with local first responders,” company spokesperson Lena Kent said in a statement.

Researchers create self-sensing metamaterial concrete that produce power

University of Pittsburgh.

A metamaterial is any material engineered to have a property that is elusive to naturally occurring materials. The research introduces the use of metamaterials in the creation of concrete, providing the option to alter its brittleness, flexibility, and shapeability to allow builders to use less of the material without sacrificing strength or longevity.

Beaming in a Spin Texture

Researchers use an optical vortex beam to create a stable pattern of electron spins in a thin layer of semiconductor material.

Spin-based electronic, or “spintronic,” devices can benefit from techniques that coax electron spins into static spatial patterns called spin textures. A new experiment demonstrates that an optical vortex—a light beam that carries orbital angular momentum—can generate a stable spin texture in a semiconductor [1]. The research team showed that the vortex generates a pattern of stripes that has potential uses in processing spin information. Previous experiments have optically stimulated these striped textures, but the optical vortex has a structure that approximately overlaps with the stripe pattern, allowing faster spin-texture formation.

The spins of unbound electrons in a material can be aligned by a magnetic field or by polarized light. But as these electrons move—either through diffusion or through conduction—their spins will begin to rotate in response to so-called spin-orbit interactions within the material. The direction and rate of these rotations for any given electron depend on the path that it takes. Thus, two nearby electrons that start out aligned will become misaligned as they move along different paths, even if they arrive at the same destination. So maintaining an electronic spin texture seems like a doomed enterprise.

Graphene grows—physicists find a way to visualize it

Graphene is one of the strongest materials. On top of that, it is exceptionally good at conducting heat and electrical currents, making it one of the most special and versatile materials we know. For all these reasons, the discovery of graphene was awarded the Nobel Prize in Physics in 2010.

Yet, many properties of the material and its cousins are still poorly understood—for the simple reason that the atoms they are made up of are very difficult to observe. A team of researchers from the University of Amsterdam and New York University have now found a surprising way to solve this issue.

Two-dimensional materials, consisting of a hyper-thin single layer of atomic crystal, have attracted a lot of attention recently. This well-deserved attention is mainly due to their unusual properties, very different from their three-dimensional ‘bulk’ counterparts. Graphene, the most famous representative, and many other , are nowadays researched intensely in the laboratory.

Scientists discover easy way to make atomically-thin metal layers for new technology

The secret to a perfect croissant is the layers—as many as possible, each one interspersed with butter. Similarly, a new material with promise for new applications is made of many extremely thin layers of metal, between which scientists can slip different ions for various purposes. This makes them potentially very useful for future high-tech electronics or energy storage.

Until recently, these materials—known as MXenes, pronounced “max-eens”—were as labor-intensive as good croissants made in a French bakery.

But a new breakthrough by scientists with the University of Chicago shows how to make these MXenes far more quickly and easily, with fewer toxic byproducts.