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Silicon is the best-known semiconductor material. However, controlled nanostructuring drastically alters the material's properties. Using a specially developed etching apparatus, a team has now produced mesoporous silicon layers with countless tiny pores and investigated their electrical and thermal conductivity. For the first time, the researchers elucidated the electronic transport mechanism in this mesoporous silicon. The material has great potential for applications and could also be used to thermally insulate qubits for quantum computers.

Silicon is the best-known semiconductor material. However, controlled nanostructuring drastically alters the material's properties. Using a specially developed etching apparatus, a team has now produced mesoporous silicon layers with countless tiny pores and investigated their electrical and thermal conductivity. For the first time, the researchers elucidated the electronic transport mechanism in this mesoporous silicon. The material has great potential for applications and could also be used to thermally insulate qubits for quantum computers.

Cadmium selenide nanoplatelets provide a promising foundation for the development of innovative electronic materials. Since the turn of the millennium, researchers around the world have taken a particular interest in these tiny platelets, which are only a few atoms thick, as they offer extraordinary optical and other properties. A team has now taken an important step towards the systematic production of such nanoplatelets.

Researchers have invented an entirely new field of microscopy -- nuclear spin microscopy. The team can visualize magnetic signals of nuclear magnetic resonance with a microscope. Quantum sensors convert the signals into light, enabling extremely high-resolution optical imaging.

Researchers have invented an entirely new field of microscopy -- nuclear spin microscopy. The team can visualize magnetic signals of nuclear magnetic resonance with a microscope. Quantum sensors convert the signals into light, enabling extremely high-resolution optical imaging.

An international team of researchers has successfully captured the internal structure of the longest-runout sediment flow ever recorded on Earth. Using seismic measurements, the researchers have for the first time been able to analyze in detail the internal structure of these tens to hundreds of kilometers long turbidity currents -- an oceanographic phenomenon that has been studied for almost a century, but never directly observed. The new insights into the dynamics of these powerful currents will help improve risk assessments for underwater infrastructure, such as submarine cables, and refine models of sediment and carbon transport in the ocean.

How does a tennis player like Carlos Alcaraz decide where to run to return Novak Djokovic's ball by just looking at the ball's initial position? These behaviours, so common in elite athletes, are difficult to explain with current computational models, which assume that the players must continuously follow the ball with their eyes. Now, researchers have developed a model that, by combining optical variables with environmental factors such as gravity, accurately predicts how a person will move to catch a moving object just from an initial glance. These results could have potential applications in fields such as robotics, sports training or even space exploration.

How does a tennis player like Carlos Alcaraz decide where to run to return Novak Djokovic's ball by just looking at the ball's initial position? These behaviours, so common in elite athletes, are difficult to explain with current computational models, which assume that the players must continuously follow the ball with their eyes. Now, researchers have developed a model that, by combining optical variables with environmental factors such as gravity, accurately predicts how a person will move to catch a moving object just from an initial glance. These results could have potential applications in fields such as robotics, sports training or even space exploration.

Per- and polyfluoroalkyl substances (PFAS) are known as forever chemicals because of their extreme persistence. These compounds have useful properties including durability and waterproofing, so they're commonly used in consumer products like food packaging and cosmetics, as well as industrial processes. But PFAS' potential negative impacts on human health are driving the search for potentially safer substitutes. Now, researchers propose alternatives for many applications.

Heteroepitaxial growth technology has made it possible to create larger diamond substrates, opening new opportunities for industrial-scale production of diamond quantum sensors. A research team has successfully fabricated large-area (111)-orientated diamond crystal substrates on heterogeneous (non-diamond) substrates, demonstrating the potential for industrialization of precise, noise-resistant current measurements for electric vehicle battery monitoring.

Grouting is a widely used construction technique that involves injecting stabilizing materials into soil to ensure structural stability, which is especially beneficial in earthquake-prone regions. Now, scientists have developed an innovative, carbon-neutral grout made from waste fluids of geothermal energy harvesting systems. Their new material shows a 50% increase in liquefaction resistance compared to conventional grouts, while also addressing environmental concerns associated with the construction industry.

Researchers detail advances in the measurement of quantum devices that will be needed to realize a topological quantum computer. In an announcement, the team describes the operation of a device that is a necessary building block for a topological quantum computer. The published results are an important milestone along the path to construction of quantum computers that are potentially more robust and powerful than existing technologies.

Researchers detail advances in the measurement of quantum devices that will be needed to realize a topological quantum computer. In an announcement, the team describes the operation of a device that is a necessary building block for a topological quantum computer. The published results are an important milestone along the path to construction of quantum computers that are potentially more robust and powerful than existing technologies.

Technology could lead to faster, more precise and more cost-effective alternatives to traditional diagnostic methods.

Discarded food scraps, stray branches, seashells and many other natural materials are key ingredients in a system that can pull drinkable water out of thin air developed by researchers.

Researchers have developed a battery that can convert nuclear energy into electricity via light emission, a study suggests.

Most AI diagnostic tools are black boxes, but the approach allows doctors and patients to understand how the computer reached a diagnosis.

Keeping work surfaces clean during meat processing is a challenge, and now researchers deliver key insights into a solution that could change the current practice altogether: Instead of working to prevent bacteria buildup, they created surfaces that stop bacteria from attaching in the first place. Using lasers to etch and alter the surface of the metal, the team was able to create micro- or nanoscale textures that make it difficult for microbial cells to attach to the surface. The technique, known as laser-induced surface texturing, also alters the metal's water-repellent properties.

Air travel produces around 2.5% of all global CO2 emissions, and despite decades of effort in developing alternative fuels or more efficient aircraft designs, that number hasn’t budged much. However, NASA, also the US’s Aeronautics administration, has kept plugging away at trying to build a more sustainable future for air travel. Recently, they supported another step in that direction by providing an Institute for Advanced Concepts (NIAC) grant to Phillip Ansell of the University of Illinois Urbana-Champaign to develop a hybrid hydrogen-based aircraft engine.

The grant focuses on developing the Hydrogen Hybrid Power for Aviation Sustainable Systems (Hy2PASS) engine, a hybrid engine that uses a fuel cell and a gas turbine to power an aircraft. Hybrid systems have been tried before, but Hy2PASS’s secret sauce is its use of air handling.

In hybrid aircraft systems, there’s typically a fuel cell and a gas turbine. The fuel cell takes hydrogen as an input and creates electrical energy as output. In a typical hybrid system, this electrical energy would power a compressor, whose output was directly coupled to turning the turbine. However, in Hy2PASS, the compressor itself is decoupled from the turbine, though it still supplies oxygen to it. It then also supplies oxygen to the fuel cell’s cathode, allowing for its continued operation.

AI generated video on the Hy2PASS system.

This method has a few advantages, but the most significant one is the dramatic increase in efficiency it allows. The waste heat created at that mechanical connection is eliminated by uncoupling the compressor directly from the turbine. Also, it allows the compressor to be run at different pressures, allowing an algorithm to optimize its speed while ignoring the necessary speed of the turbine.

Additionally, the emissions from the entire system are essentially just water. So, this hybrid system effectively eliminates the emissions created by this kind of hybrid engine altogether. So, in theory, at least, this type of propulsion system would be the holy grail that NASA and the rest of the aviation industry have been seeking for years.

There’s still a long way to go to make this system a reality. The Phase I NIAC grant will focus on proving the system’s concept. Importantly, it will also require an understanding of another aircraft system and “mission trajectory optimization” to minimize the energy requirements of any future use case for the system. That sounds like there would be some limitations for how the system might be used in practice, though fleshing that out as part of Phase I seems a reasonable use case.

Interview with Dr. Ansell, the PI on the Hy2PASS project.

If the project is successful, and given Dr. Ansell’s track record of consistently meeting NASA design objectives, that seems a good bet. It is possible that someday soon, a hydrogen-powered aircraft could be in the air again. And this time, it will be a key player in eliminating emissions from one of the most important industries in the world.

Learn More:
NASA – Hydrogen Hybrid Power for Aviation Sustainable Systems (Hy2PASS)
UT – Multimode Propulsion Could Revolutionize How We Launch Things to Space
UT – Reaction Engines Goes Into Bankruptcy, Taking the Hypersonic SABRE Engine With it
UT – NASA is Working on Electric Airplanes

Lead Image:
Artist’s concept of the Hy2PASS engine
Credit – NASA / Phillip Ansell

The post A Hybrid Hydrogen Drive Train Could Eliminate Aircraft Emissions appeared first on Universe Today.

The frozen remains of animals like mammoths, wolves and cave lions offer the most detailed picture yet of the last glacial period