Archive for the ‘materials’ category: Page 121

Dec 23, 2020

World’s first wooden satellite to be launched by Japan in 2023

Posted by in categories: materials, space

Who knew wood could still be useful in space. 😃

TOKYO — Japanese logging company Sumitomo Forestry and Kyoto University are planting the seeds for a 2023 launch of the world’s first satellite made out of wood.

The partners announced their intentions on Wednesday, saying the aim was basic research and proof of concept.

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Dec 23, 2020

The International Space Station is now home to the world’s 1st commercial airlock

Posted by in categories: materials, space

CAPE CANAVERAL, Fla. — The International Space Station is now sporting a shiny new piece of hardware.

On Monday (Dec. 21), the first commercial airlock ever sent to the International Space Station (ISS) was attached to its exterior. The new structure is a bell-shaped airlock that is designed to transfer payloads and other materials from inside the station out into the vacuum of space.

Dec 23, 2020

HP’s 3D Printers Build Items Not of Plastic but of Steel

Posted by in categories: materials, transportation

For now, the company’s new Metal Jet printers make key fobs and other doodads. But one day they could create car parts.

Dec 23, 2020

Researchers develop new way to break reciprocity law

Posted by in categories: law, materials

An international research team lead by Aalto University has found a new and simple route to break the reciprocity law in the electromagnetic world, by changing a material’s property periodically in time. The breakthrough could help to create efficient nonreciprocal devices, such as compact isolators and circulators, that are needed for the next generation of microwave and optical communications systems.

When we look through a window and see our neighbor on the street, the neighbor can also see us. This is called reciprocity, and it is the most common physical phenomenon in nature. Electromagnetic signals propagating between two sources is always governed by reciprocity law: if the signal from source A can be received by source B, then the signal from source B can also be received by source A with equal efficiency.

Researchers from Aalto University, Stanford University, and Swiss Federal Institute of Technology in Lausanne (EPFL) have successfully demonstrated that the reciprocity law can be broken if the property of the propagation medium periodically changes in time. Propagation medium refers to a material in which light and waves survive and propagate from one point to another.

Dec 20, 2020

Speed of magnetic domain walls found to be fundamentally limited

Posted by in categories: materials, particle physics

A team of researchers from MIT and several institutions in Korea has found that the speed of magnetic domain wall movement is fundamentally limited. In their paper published in the journal Science, the group describes testing a theory regarding the maximum speed of domain walls to prove them correct. Matthew Daniels and Mark Stiles with the National Institute of Standards and Technology in the U.S. have published a Perspective piece outlining the work by the researchers in the same journal issue and sum up the implications of their findings.

One of the basic tenets of Einstein’s theory of special relativity is that there is no particle that can travel faster than the of light. In this new effort, the researchers have found a similar boundary for .

Materials that are magnetic have domains in which ordered spins are separated from one another by boundaries known as walls. Prior research has shown that such walls can be moved by applying an . This particular aspect of magnetic materials has formed the basis of research on racetrack . And because the speed of movement of the domain walls determines the speed of the memories created using them, scientists have been pushing them faster and faster. Logic suggests that there must be a limit to how fast the domain walls can be pushed, however, thus establishing a limit to how fast such memories can operate. In this new effort, the researchers have found that fundamental limit.

Dec 20, 2020

Unexpected theoretical breakthrough in the field of electromagnetism

Posted by in categories: materials, nanotechnology

How electrons move together as a group inside cylindrical nanoparticles?

Scientists from the University of Exeter seems to find out the answer to this question. They even have made a breakthrough in the field of electromagnetism, with perspectives for metamaterials research.

In collaboration with the University of Strasbourg, scientists hypothesized how electrons move collectively in tiny metal nanoparticles shaped like cylinders.

Dec 19, 2020

Light-activated material stores potential energy for months or years

Posted by in categories: biotech/medical, materials

Researchers at Lancaster University have developed a new material that can store energy for months, and potentially years, at a time. The material can be activated by light, and then release the pent-up energy on demand in the form of heat.

The team started with a metal-organic framework (MOF), materials that are famous for being very porous and as such, having an extremely high surface area. That in turn allows them to hold onto large amounts of molecules, making them great for desalinating or filtering water, capturing carbon dioxide out of the air, or delivering drugs in the body.

For the new study, the Lancaster researchers tested out how well a MOF might be able to store energy. They started with a version of the material called a DMOF1, and loaded its pores with azobenzene molecules. This compound is excellent at absorbing light, which causes its molecules to physically change shape.

Dec 16, 2020

Researchers develop new combined process for 3D printing

Posted by in categories: biotech/medical, materials

Chemists at Martin Luther University Halle-Wittenberg (MLU) have developed a way to integrate liquids directly into materials during the 3D printing process. This allows, for example, active medical agents to be incorporated into pharmaceutical products or luminous liquids to be integrated into materials, which allow monitoring of damage. The study was published in Advanced Materials Technologies.

3D is now widely used for a range of applications. Generally, however, the method is limited to materials which are liquefied through heat and become solid after printing. If the finished product is to contain liquid components, these are usually added afterwards. This is time-consuming and costly. “The future lies in more complex methods that combine several production steps,” says Professor Wolfgang Binder from the Institute of Chemistry at MLU. “That is why we were looking for a way to integrate liquids directly into the material during the .”

To this endeavor, Binder and his colleague Harald Rupp combined common 3D printing processes with traditional printing methods such as those used in inkjet or laser printers. Liquids are added drop by drop at the desired location during the extrusion of the basic material. This allows them to be integrated directly and into the material in a targeted manner.

Dec 16, 2020

Tailoring Magnetic Fields in Inaccessible Regions

Posted by in category: materials

Controlling magnetism, essential for a wide range of technologies, is impaired by the impossibility of generating a maximum of magnetic field in free space. Here, we propose a strategy based on negative permeability to overcome this stringent limitation. We experimentally demonstrate that an active magnetic metamaterial can emulate the field of a straight current wire at a distance. Our strategy leads to an unprecedented focusing of magnetic fields in empty space and enables the remote cancellation of magnetic sources, opening an avenue for manipulating magnetic fields in inaccessible regions.

Dec 15, 2020

When less is more: A single layer of atoms boosts the nonlinear generation of light

Posted by in categories: materials, particle physics

In a new study an international research team led by the University of Vienna has shown that structures built around a single layer of graphene allow for strong optical nonlinearities that can convert light. The team achieved this by using nanometer-sized gold ribbons to squeeze light, in the form of plasmons, into atomically-thin graphene. The results, which are published in Nature Nanotechnology are promising for a new family of ultra-small tunable nonlinear devices.

In the last years, a concerted effort has been made to develop plasmonic devices to manipulate and transmit through nanometer-sized devices. At the same time, it has been shown that nonlinear interactions can be greatly enhanced by using plasmons, which can arise when light interacts with electrons in a material. In a plasmon, light is bound to electrons on the surface of a conducting material, allowing plasmons to be much smaller than the light that originally created them. This can lead to extremely strong nonlinear interactions. However, plasmons are typically created on the surface of metals, which causes them to decay very quickly, limiting both the propagation length and nonlinear interactions. In this new work, the researchers show that the long lifetime of plasmons in and the strong nonlinearity of this material can overcome these challenges.

In their experiment, the research team led by Philip Walther at the University of Vienna (Austria), in collaboration with researchers from the Barcelona Institute of Photonic Sciences (Spain), the University of Southern Denmark, the University of Montpellier, and the Massachusetts Institute of Technology (USA) used stacks of two-dimensional materials, called heterostructures, to build up a nonlinear plasmonic device. They took a single atomic layer of graphene and deposited an array of metallic nanoribbons onto it. The metal ribbons magnified the incoming light in the graphene layer, converting it into graphene plasmons. These plasmons were then trapped under the gold nanoribbons, and produced light of different colors through a process known as harmonic generation. The scientists studied the generated light, and showed that, the nonlinear interaction between the graphene plasmons was crucial to describe the harmonic generation.