With new heat treatment, 3D-printed metals can withstand extreme conditions

A thin rod of 3D-printed superalloy is drawn out of a water bath, and through an induction coil, where it is heated to temperatures that transform its microstructure, making the material more resilient. The new MIT heat treatment could be used to reinforce 3D-printed gas turbine blades.
Credit: Dominic David Peachey

A new MIT-developed heat treatment transforms the microscopic structure of 3D-printed metals, making the materials stronger and more resilient in extreme thermal environments. The technique could make it possible to 3D print high-performance blades and vanes for power-generating gas turbines and jet engines, which would enable new designs with improved fuel consumption and energy efficiency.

Today’s gas turbine blades are manufactured through conventional casting processes in which molten metal is poured into complex molds and directionally solidified. These components are made from some of the most heat-resistant metal alloys on Earth, as they are designed to rotate at high speeds in extremely hot gas, extracting work to generate electricity in power plants and thrust in jet engines.

There is growing interest in manufacturing turbine blades through 3D-printing, which, in addition to its environmental and cost benefits, could allow manufacturers to quickly produce more intricate, energy-efficient blade geometries. But efforts to 3D-print turbine blades have yet to clear a big hurdle: creep.

In metallurgy, creep refers to a metal’s tendency to permanently deform in the face of persistent mechanical stress and high temperatures. While researchers have explored printing turbine blades, they have found that the printing process produces fine grains on the order of tens to hundreds of microns in size — a microstructure that is especially vulnerable to creep.

“In practice, this would mean a gas turbine would have a shorter life or less fuel efficiency,” says Zachary Cordero, the Boeing Career Development Professor in Aeronautics and Astronautics at MIT. “These are costly, undesirable outcomes.”

Boeing-Built X-37B Completes Sixth Mission, Sets New Endurance Record

The Boeing-built X-37B Orbital Test Vehicle (OTV) landed at NASA’s Kennedy Space Center in Florida at 5:22 a.m. ET, November 12, 2022.
Photo Credit: Boeing / U.S. Space Force

The Boeing built X-37B Orbital Test Vehicle (OTV) set a new endurance record after spending 908 days in orbit before landing at NASA’s Kennedy Space Center in Florida at 5:22 a.m. ET, November 12, 2022. This surpasses its previous record of 780 days on-orbit.

With the successful completion of its sixth mission the reusable spaceplane has now flown over 1.3 billion miles and spent a total of 3,774 days in space where it conducts experiments for government and industry partners with the ability to return them to Earth for evaluation.

For the first time, the vehicle carried a service module to augment the number of payloads it can haul. The module separated from the OTV prior to de-orbiting ensuring a safe and successful landing.

“This mission highlights the Space Force's focus on collaboration in space exploration and expanding low-cost access to space for our partners, within and outside of the Department of the Air Force (DAF),” said Gen. Chance Saltzman, Chief of Space Operations.

Previously unseen processes reveal path to better rechargeable battery performance

Materials science and engineering postdoctoral researcher Wenxiang Chen is the first author of a new study that applies imaging techniques common in ceramics and metallurgy to rechargeable ion battery research. 
Photo by Fred Zwicky

To design better rechargeable ion batteries, engineers and chemists from the University of Illinois Urbana-Champaign collaborated to combine a powerful new electron microscopy technique and data mining to visually pinpoint areas of chemical and physical alteration within ion batteries.

A study led by materials science and engineering professors Qian Chen and Jian-Min Zuo is the first to map out altered domains inside rechargeable ion batteries at the nanoscale – a 10-fold or more increase in resolution over current X-ray and optical methods.

The findings are published in the journal Nature Materials.

The team said previous efforts to understand the working and failure mechanisms of battery materials have primarily focused on the chemical effect of recharging cycles, namely the changes in the chemical composition of the battery electrodes.

A new electron microscopy technique, called four-dimensional scanning transmission electron microscopy, allows the team to use a highly focused probe to collect images of the inner workings of batteries.

Novel Nanowire Fabrication Technique Paves Way for Next Generation Spintronics

The challenge of fabricating nanowires directly on silicon substrates for the creation of the next generation of electronics has finally been solved by researchers from Tokyo Tech. Next-generation spintronics will lead to better memory storage mechanisms in computers, making them faster and more efficient.

As our world modernizes faster than ever before, there is an ever-growing need for better and faster electronics and computers. Spintronics is a new system which uses the spin of an electron, in addition to the charge state, to encode data, making the entire system faster and more efficient. Ferromagnetic nanowires with high coercivity (resistance to changes in magnetization) are required to realize the potential of spintronics. Especially L10-ordered (a type of crystal structure) cobalt–platinum (CoPt) nanowires.

Conventional fabrication processes for L10-ordered nanowires involve heat treatment to improve the physical and chemical properties of the material, a process called annealing on the crystal substrate; the transfer of a pattern onto the substrate through lithography; and finally, the chemical removal of layers through a process called etching. Eliminating the etching process by directly fabricating nanowires onto the silicon substrate would lead to a marked improvement in the fabrication of spintronic devices. However, when directly fabricated nanowires are subjected to annealing, they tend to transform into droplets as a result of the internal stresses in the wire.

New international study concludes digital media can fuel polarization and populism

Image Credit: Thomas Ulrich

The question of whether the rise in usage of digital media is contributing to the erosion of democracy is a source of popular debate, with tech companies arguing the findings are inconclusive.

But now a team of international researchers has carried out a comprehensive review of hundreds of studies globally, the biggest of its kind, exploring this claim and found that while social media is not exclusively bad, it can certainly stoke starkly conflicting views, populism, and political mistrust especially in established democracies.

The researchers, from the Max Planck Institute for Human Development and the Hertie School in Germany, and the University of Bristol in the UK, systematically assessed studies investigating whether and how digital media impacts people’s political behavior. Studies show that although some effects may be beneficial for democracy, for instance digital media can increase political knowledge and diversity of news exposure, they also have detrimental effects, such as fostering polarization and populism.

Furthermore, the way consequences such as increased political mobilization and decreasing trust in institutions play out depends largely on the political context. Such developments were found to be beneficial in emerging democracies but can have destabilizing effects in established democracies.

A Brain Stimulator That Powers with Breath Instead of Batteries

UConn researchers have developed a way of charging deep brain stimulators that don't require the battery power that's currently standard
Credit/Source: University of Connecticut Contributed Illustration

Implantable deep brain stimulators can help many people with neurological and psychiatric disease when traditional treatments fail. But surgery every time the batteries need to be changed is a major drawback. Now, UConn researchers report in Cell Reports Physical Sciences a new way to charge the devices using a person’s own breathing movements.

Deep brain stimulators are becoming more common, with about 150,000 new devices implanted each year. They are normally placed under the skin in the chest area and their electrodes implanted within the brain. The electrodes zap the brain with electrical pulses multiple times per second to regulate the brain’s abnormal electrical activity. Deep brain stimulators can help people with Parkinson’s disease and other movement disorders to regain control over their muscle motions. Research has also shown the technique can significantly reduce the symptoms for psychiatric conditions such as treatment-resistant depression and obsessive-compulsive disorder.

Just like a pacemaker, deep brain stimulators are battery powered. While most pacemaker batteries last from 7-10 years, deep brain stimulator batteries typically require changing every 2-3 years because of their high energy consumption. And each battery change requires surgery.

UConn chemists Esraa Elsanadidy, Islam Mosa, James Rusling, and their collaborators have developed a deep brain stimulator that never needs its batteries changed.

Patient-specific cancer tumors replicated in 3D bioprinting advance

Electron micrograph of a grown, hydrogel-embedded tumor spheroid.
Image Credit: University of Bristol

Bowel cancer patients could in future benefit from a new 3D bioprinting technology which would use their own cells to replicate the complex cellular environment of solid tumors in 3D models. The University of Bristol-led advance, published in Biofabrication, would allow clinicians to treat the models, known as spheroids, with chemotherapy drugs and radiation to help them understand an individual patient’s resistance to therapies.

Bowel cancer is the third-most prevalent cancer worldwide, a major cause of cancer-related deaths and is becoming more prevalent globally each year. While current therapies aim to shrink tumors through a combination of surgery, chemotherapy and/or radiotherapy, the heterogenous nature of bowel tumors mean that chemotherapy drugs have variable effects between patients.

In this new study, researchers developed a new 3D bioprinting platform with high content light microscopy imaging and processing. Using a mixture of bioinks and colorectal (bowel) cancer cells, the team showed they were able to replicate tumors in 3D spheroids.

To investigate how the tumors might respond to drugs, dose-response profiles were generated from the spheroids which had been treated separately with chemotherapy drugs oxaliplatin (OX), fluorouracil (5FU), and radiotherapy. The spheroids were then imaged over time. Results from their experiment showed oxaliplatin was significantly less effective against tumor spheroids than in current 2D monolayer culture structures, when compared to fluorouracil.

A New Protocol for Live Imaging Emerges from MBL Embryology Course

A stylized image of a nematode worm (C. elegans) adult encircled by embryos.
Credit: Yicong Wu

The beauty of live-imaging studies is that the specimen is alive, allowing dynamics such as cell division and embryonic development to be recorded over time.

Yet the frustration of live-imaging studies is the specimen is alive – wriggling, twisting, escaping the field of view. Plus, it’s delicate, susceptible to heat damage or death from the imaging equipment itself.

A technical solution to this quandary recently emerged from the MBL Embryology course, in “a classic example of the collaborative effort here at MBL,” says MBL Imaging Research Specialist Carsten Wolff.

“During the 2021 Embryology course, we started to develop a technique that enables us to image adult C. elegans worms for longer periods of time, and at high resolution, using light sheet microscopy,” says Wolff. A group of course faculty and staff, collaborating with MBL imagers, fine-tuned the protocol during the 2022 course and wrote up the paper, which is published this month in Frontiers in Cell and Developmental Biology.

The nematode C. elegans is a popular organism in biological and biomedical research. Light-sheet fluorescence microscopy (LSFM) has been very successful in capturing embryonic processes in C. elegans, as well as in mice and zebrafish. But once the organisms hatch out, LSFM presents limitations.

New Material for Perovskite Solar Cells Proposed in Russia

Scientists have proposed a new type of material for transporting electrons in perovskite solar cells.
 Photo Credit: Vladimir Petrov

Experts from the Ural Federal University and the Institute of Organic Synthesis of the Ural Branch of the Russian Academy of Sciences, together with other Russian scientists, have proposed a new type of material for one of the solar cell cells. The discovered compounds will significantly reduce the cost of solar cell production. An article with the results of the study was published in the New Journal of Chemistry.

Perovskite solar cells (PSCs) are a promising alternative to the familiar silicon cells, providing the same amount of energy with 180 times less material thickness. Their production technology is much simpler and cheaper than that of silicon cells. The problem with PSCs is their lack of stability. One of the most effective solutions today, as explained by the experts, is the selection of new materials that ensure the transport of the charge carriers after it is obtained in the perovskite layer itself.

The scientific team of the Ural Federal University and the Institute of Organic Synthesis of the Ural Branch of the Russian Academy of Sciences proposed a new type of material for transporting electrons in the PSCs, which has a number of advantages. According to the authors, with the new material they managed to achieve solar energy conversion efficiency of 12%, which is comparable with the average indicators of market analogues.

Step by step

Berkeley researchers may be one step closer to making robot dogs our new best friends. Using advances in machine learning, two separate teams have developed cutting-edge approaches to shorten in-the-field training times for quadruped robots, getting them to walk — and even roll over — in record time.

In a first for the robotics field, a team led by Sergey Levine, associate professor of electrical engineering and computer sciences, demonstrated a robot learning to walk without prior training from models and simulations in just 20 minutes. The demonstration marks a significant advancement, as this robot relied solely on trial and error in the field to master the movements necessary to walk and adapt to different settings.

“Our work shows that training robots in the real world is more feasible than previously thought, and we hope, as a result, to empower other researchers to start tackling more real-world problems,” said Laura Smith, a Ph.D. student in Levine’s lab and one of the lead authors of the paper posted on arXiv.

In past studies, robots of comparable complexity required several hours to weeks of data input to learn to walk using reinforcement learning (RL). Often, they also were trained in controlled lab settings, where they learned to walk on relatively simple terrain and received precise feedback about their performance.

International Collaboration Is Key to Addressing Global Climate Change

Estimated annual savings from deployed annual solar PV modules using global versus national market scenarios in China, Germany and the United States (2008-2020). 
Credit: Helveston, He and Davidson 2022

Study Quantifies for First Time Past and Future Country Cost Savings to Solar Industry from Globalized Supply Chains

The world will need to deploy renewable energy at an unprecedented speed and scale in the future to reduce carbon emissions that are driving climate change. The option of solar energy promises to play a crucial role in achieving a sustainable, low-carbon energy future, especially if the price of production continues to decline as it has over the last 40 years.

A new study published in Nature by a team of scientists including Gang He, assistant professor in the Department of Technology and Society in the College of Engineering and Applied Sciences at Stony Brook University, supports this concept. Findings from the paper reveal that the globalized supply chain of solar photovoltaics saved countries $67 billion in solar module production costs. The study also found that if strong nationalistic policies that limit the free flow of goods, talent and capital are implemented going forward, solar panel costs will be much higher by 2030.

High-tech sensors could guide vehicles without satellites, if they can handle the ride

Sandia National Laboratories atomic physicist Jongmin Lee examines the sensor head of a cold-atom interferometer that could help vehicles stay on course where GPS is unavailable.
Photo credit: Bret Latter

Words like “tough” or “rugged” are rarely associated with a quantum inertial sensor. The remarkable scientific instrument can measure motion a thousand times more accurately than the devices that help navigate today’s missiles, aircraft and drones. But its delicate, table-sized array of components that includes a complex laser and vacuum system has largely kept the technology grounded and confined to the controlled settings of a lab.

Jongmin Lee wants to change that.

The atomic physicist is part of a team at Sandia National Laboratories that envisions quantum inertial sensors as revolutionary, onboard navigational aids. If the team can reengineer the sensor into a compact, rugged device, the technology could safely guide vehicles where GPS signals are jammed or lost.

In a major milestone toward realizing their vision, the team has successfully built a cold-atom interferometer, a core component of quantum sensors, designed to be much smaller and tougher than typical lab setups. The team describes their prototype in the academic journal Nature Communications, showing how to integrate several normally separated components into a single monolithic structure. In doing so, they reduced the key components of a system that existed on a large optical table down to a sturdy package roughly the size of a shoebox.

Penguin feathers may be secret to effective anti-icing technology

Gentoo penguins
Photo Credit: 66 north

Ice buildup on powerlines and electric towers brought the northern US and southern Canada to a standstill during the Great Ice Storm of 1998, leaving many in the cold and dark for days and even weeks. Whether it is on wind turbines, electric towers, drones, or airplane wings, dealing with ice buildup typically depends on techniques that are time consuming, costly and/or use a lot of energy, along with various chemicals. But, by looking to nature, McGill researchers believe that they have found a promising new way of dealing with the problem. Their inspiration came from the wings of Gentoo penguins who swim in the ice-cold waters of the south polar region, with pelts that remain ice-free even when the outer surface temperature is well below freezing.

We initially explored the qualities of the lotus leaf, which is very good at shedding water but proved less effective at shedding ice,” said Anne Kietzig, who has been looking for a solution for close to a decade. She is an associate professor in Chemical Engineering at McGill and the director of the Biomimetic Surface Engineering Laboratory. “It was only when we started investigating the qualities of penguin feathers that we discovered a material found in nature that was able to shed both water and ice.”

Scientists Created a Material Promising for Improving Brightness of Screens

One of the assembled organic LEDs based on push-pull systems.
Photo credit: Ruslan Gadirov / TSU

Scientists at the Postovsky Institute of Organic Synthesis, Ural Branch of the Russian Academy of Sciences, and Ural Federal University have developed, synthesized, and studied a series of new fluorophores - push-pull systems (compounds with pronounced electron-donor and electron-acceptor parts) based on cyanopyrazine. Ural chemists in cooperation with colleagues from Tomsk State University showed that the presence of a cyano group in the substance significantly increases the efficiency of organic light emitting diodes (OLEDs) based on it. This opens the prospect of creating new materials to enhance the brightness of displays of smartphones, computers and televisions. An article describing the research and its results was published in the journal Dyes and Pigments.

In previous research work, chemists demonstrated that one of the most promising compounds as an acceptor (attracting electrons) part in push-pull systems is the pyrazine ring (another name is 1,4-diazine), a compound of nitrogen, hydrogen and carbon that has a significant electron-accepting effect.

A laser that could ‘reshape the landscape of integrated photonics’

A team of researchers led by Qiang Lin, a professor of electrical and computer engineering at Rochester, has developed the first multi-color integrated laser that emits high-coherence light at telecommunication wavelengths, allows laser-frequency tuning at record speeds, and is the first narrow linewidth laser with fast configurability at the visible band.
Credit: University of Rochester / J. Adam Fenster

How do you integrate the advantages of a benchtop laser that fills a room onto a semiconductor chip the size of a fingernail?

A research team co-led by Qiang Lin, a professor of electrical and computer engineering at the University of Rochester, has set new milestones in addressing this challenge, with the first multi-color integrated laser that:

• Emits high-coherence light at telecommunication wavelengths
• Allows laser-frequency tuning at record speeds
• Is the first narrow linewidth laser with fast configurability at the visible band

The project, described in Nature Communications, was co-led by John Bowers, distinguished professor at University of California/Santa Barbara, and Kerry Vahala, professor at the California Institute of Technology. Lin Zhu, professor at Clemson University, also collaborated on the project.

Ural Scientists Created Nanoparticle Growth Technology

The new material is suitable for solar cells, biosensors, and other systems working on quantum principles.
Photo credit: Vladimir Petrov

Physicists at Ural Federal University and their colleagues from the Institute of Electrophysics, Ural Branch of the Russian Academy of Sciences, and the Institute of Ion Plasma and Laser Technologies, Academy of Sciences, have developed a technology for growing nonspherical nanoparticles that are synthesized by ion implantation. With the new technique, it is possible to grow nanoparticles of different shapes and thus obtain the necessary properties and control them. The technology is applicable to different metals, both noble metals such as gold, silver, platinum, and "ordinary", the scientists assure. A description of the technology and the results of the first experiments - copper implantation in ceramics - are presented in the Journal of Physics and Chemistry of Solids.

"By changing the shape of nanoparticles from spherical to non-spherical, we were able to increase the range of optical absorption. This, in turn, is the basis for further converting the absorbed energy into electricity and heat. As a result, we can get more functional sensors and increase their sensitivity range. If such nanoparticles are built into lasers, their power will increase. If we talk about sensors, their sensitivity will increase. As for sensors, their response time will change. This is all due to the peculiarity of plasmon resonance, which leads to the fact that around the nanoparticles there is an amplified electric field," explains study co-author Arseny Kiryakov, Associate Professor at the Department of Physical Techniques and Devices for Quality Control at UrFU.

Reprogrammable materials selectively self-assemble

With just a random disturbance that energizes the cubes, they selectively self-assemble into a larger block. 

Credit: MIT CSAIL

While automated manufacturing is ubiquitous today, it was once a nascent field birthed by inventors such as Oliver Evans, who is credited with creating the first fully automated industrial process, in flour mill he built and gradually automated in the late 1700s. The processes for creating automated structures or machines are still very top-down, requiring humans, factories, or robots to do the assembling and making.

However, the way nature does assembly is ubiquitously bottom-up; animals and plants are self-assembled at a cellular level, relying on proteins to self-fold into target geometries that encode all the different functions that keep us ticking. For a more bio-inspired, bottom-up approach to assembly, then, human-architected materials need to do better on their own. Making them scalable, selective, and reprogrammable in a way that could mimic nature’s versatility means some teething problems, though.

Now, researchers from MIT’s Computer Science and Artificial Intelligence Laboratory (CSAIL) have attempted to get over these growing pains with a new method: introducing magnetically reprogrammable materials that they coat different parts with — like robotic cubes — to let them self-assemble. Key to their process is a way to make these magnetic programs highly selective about what they connect with, enabling robust self-assembly into specific shapes and chosen configurations.

New Chemosensors Can Detect Heavy Metals in the Body and Environment

According to Grigory Zyryanov, industrial partners, including foreign ones, are interested in the developments.
Photo credit: Anna Marinovich

Ural scientists are developing chemosensors for the diagnosis and therapy of various diseases. These are compounds that change their luminescent properties upon external exposure or contact with organic cells. They can be used to find and suppress cancer cells, diagnose cardiovascular diseases, and determine the level of sugar or drugs in the blood. One of the new developments of scientists from the UrFU is chemosensors for controlling the content of metals in the blood, since an overdose of metals can be dangerous for the body. Grigory Zyryanov, professor at the Department of Organic and Biomolecular Chemistry at Ural Federal University, spoke about this on the air of Komsomolskaya Pravda radio.

"One of our activities is the creation of chemosensors for the detection of zinc cations in biological fluids, including blood. Zinc is involved in many physiological processes in the body; it is necessary for normal growth and stabilization of cell membranes. In some cases, such as colds, taking zinc supplements can help boost the body's immune response and speed recovery. However, it is necessary to control zinc levels, since zinc overdose is toxic for the body," explains Grigory Zyryanov.

A Machine Learning-Based Solution Could Help Firefighters Circumvent Deadly Backdrafts

NIST researchers conducted hundreds of fire experiments to find out what conditions make a room ripe for backdraft and fed the data to a machine learning algorithm. The result was a backdraft-predicting computer model. The NIST's team plans to incorporate the model into handheld devices that firefighters could use to take simple measurements through small openings in a room.

A lack of oxygen can reduce even the most furious flame to smoldering ash. But when fresh air rushes in, say after a firefighter opens a window or door to a room, the blaze may be suddenly and violently resurrected. This explosive phenomenon, called backdraft, can be lethal and has been challenging for firefighters to anticipate.

Now, researchers at the National Institute of Standards and Technology (NIST) have hatched a plan for informing firefighters of what dangers lie behind closed doors. The team obtained data from hundreds of backdrafts in the lab to use as a basis for a model that can predict backdrafts. The results of a new study, described at the 2022 Suppression, Detection and Signaling Research and Applications Conference, suggest that the model offers a viable solution to make predictions based on particular measurements. In the future, the team seeks to implement the technology into small-scale devices that firefighters could deploy in the field to avoid or adapt to dangerous conditions.

Currently, firefighters are looking for visual indicators of a potential backdraft, including soot-stained windows, smoke puffing through small openings and the absence of flames. If the cues are present, they may vent the room by creating holes in its ceiling to reduce their risk. If not, they may charge right in. Ultimately, first responders must rely on their eyes in a hazy environment to guess the correct action. And guessing wrong could come at a steep cost.

New Approach Would Improve User Access to Electric Vehicle Charging Stations

Photo credit: Rick Govic.

Researchers from North Carolina State University have developed a dynamic computational tool to help improve user access to electric vehicle (EV) charging stations, with the goal of making EVs more attractive for drivers.

“We already know that there is a need for EV charging networks that are flexible, in order to support the adoption of EVs,” says Leila Hajibabai, corresponding author of a paper on the work and an assistant professor in NC State’s Fitts Department of Industrial and Systems Engineering. “That’s because there is tremendous variability in when and where people want to charge their vehicles, how much time they can spend at a charging station, how long it takes to charge their vehicles, and so on.

“The fundamental question we wanted to address with this work is: What is the best way to manage existing charging station infrastructure in order to best meet the demands of electric vehicle users?”

To answer that question, the researchers wanted to take the user’s perspective, so they focused on questions that are important to EV drivers. How long will it take me to reach a charging station? What is the cost of using the charging station? How long might I have to wait to access a charging station? And what sort of fines are there if I stay at a charging station beyond the time limit?

The researchers developed a technique that accounts for all of these factors in a complex computational model that makes use of a game theory framework.