Help Train NASA’s Rovers To Better Explore Mars – Here’s How

TOPICS:Artificial IntelligenceJPLMarsMars 2020 Perseverance RoverNASAPopular

By JET PROPULSION LABORATORY OCTOBER 27, 2021

The robotic arm of NASA’s Perseverance rover is visible in this image used by the AI4Mars project. Users outline and identify different rock and landscape features to help train an artificial intelligence algorithm that will help improve the capabilities of Mars rovers. Credit: NASA/JPL-Caltech

Members of the public can now help teach an artificial intelligence algorithm to recognize scientific features in images taken by NASA’s Perseverance rover.

Artificial intelligence, or AI, has enormous potential to change the way NASA’s spacecraft study the universe. But because all machine learning algorithms require training from humans, a recent project asks members of the public to label features of scientific interest in imagery taken by NASA’s Perseverance Mars rover.

Called AI4Mars, the project is the continuation of one launched last year that relied on imagery from NASA’s Curiosity rover. Participants in the earlier stage of that project labeled nearly half a million images, using a tool to outline features like sand and rock that rover drivers at NASA’s Jet Propulsion Laboratory typically watch out for when planning routes on the Red Planet. The end result was an algorithm, called SPOC (Soil Property and Object Classification), that could identify these features correctly nearly 98% of the time.

SPOC is still in development, and researchers hope it can someday be sent to Mars aboard a future spacecraft that could perform even more autonomous driving than Perseverance’s AutoNav technology allows.

With AI4Mars, users outline rock and landscape features in images from NASA’s Perseverance Mars rover. The project helps train an artificial intelligence algorithm for improved rover capabilities on Mars. Credit: NASA/JPL-Caltech

Images from Perseverance will further improve SPOC by expanding the kinds of identifying labels that can be applied to features on the Martian surface. AI4Mars now provides labels to identify more refined details, allowing people to choose options like float rocks (“islands” of rocks) or nodules (BB-size balls, often formed by water, of minerals that have been cemented together).

The goal is to hone an algorithm that could help a future rover pick out needles from the haystack of data sent from Mars. Equipped with 19 cameras, Perseverance sends anywhere from dozens to hundreds of images to Earth each day for scientists and engineers to comb through for specific geological features. But time is tight: After those images travel millions of miles from Mars to Earth, the team members have a matter of hours to develop the next set of instructions, based on what they see in those images, to send to Perseverance.

Parts of Perseverance are visible beside an area outlined in AI4Mars. The project already used images from NASA’s Curiosity Mars rover and help from the public to train an artificial intelligence algorithm; now the project is using images from Perseverance. Credit: NASA/JPL-Caltech

“It’s not possible for any one scientist to look at all the downlinked images with scrutiny in such a short amount of time, every single day,” said Vivian Sun, a JPL scientist who helps coordinate Perseverance’s daily operations and consulted on the AI4Mars project. “It would save us time if there was an algorithm that could say, ‘I think I saw rock veins or nodules over here,’ and then the science team can look at those areas with more detail.”

Especially during this developmental stage, SPOC requires lots of validation from scientists to ensure it’s labeling accurately. But even when it improves, the algorithm is not intended to replace more complex analyses by human scientists.

It’s All About the Data

Key to any successful algorithm is a good dataset, said Hiro Ono, the JPL AI researcher who led the development of AI4Mars. The more individual pieces of data available, the more an algorithm learns.

“Machine learning is very different from normal software,” Ono said. “This isn’t like making something from scratch. Think of it as starting with a new brain. More of the effort here is getting a good dataset to teach that brain and massaging the data so it will be better learned.”

AI researchers can train their Earth-bound algorithms on tens of thousands of images of, say, houses, flowers, or kittens. But no such data archive existed for the Martian surface before the AI4Mars project. The team would be content with 20,000 or so images in their repository, each with a variety of features labeled.

https://www.youtube.com/embed/zHXtZIYHRo8?feature=oembed
Computer Simulation of Perseverance’s First Autonav Drive: This computer simulation shows NASA’s Perseverance Mars rover as it carried out its first drive using its auto-navigation feature, which allows it to avoid rocks and other hazards without input from engineers back on Earth. Credit: NASA/JPL-Caltech

The Mars-data repository could serve several purposes, noted JPL’s Annie Didier, who worked on the Perseverance version of AI4Mars. “With this algorithm, the rover could automatically select science targets to drive to,” she said. It could also store a variety of images onboard the rover, then send back just images of specific features that scientists are interested in, she said.

That’s on the horizon; scientists may not have to wait that long for the algorithm to benefit them, however. Before the algorithm ever makes it to space, it could be used to scan NASA’s vast public archive of Mars data, allowing researchers to find surface features in those images more easily.

Ono noted it’s important to the AI4Mars team to make their own dataset publicly available so that the entire data science community can benefit.

“If someone outside JPL creates an algorithm that works better than ours using our dataset, that’s great, too,” he said. “It just makes it easier to make more discoveries.”

Visit this page to help teach Mars rovers how to classify Martian terrain.

More About the Mission

A key objective for Perseverance’s mission on Mars is astrobiology, including the search for signs of ancient microbial life. The rover will characterize the planet’s geology and past climate, pave the way for human exploration of the Red Planet, and be the first mission to collect and cache Martian rock and regolith (broken rock and dust).

Subsequent NASA missions, in cooperation with ESA (European Space Agency), would send spacecraft to Mars to collect these sealed samples from the surface and return them to Earth for in-depth analysis.

The Mars 2020 Perseverance mission is part of NASA’s Moon to Mars exploration approach, which includes Artemis missions to the Moon that will help prepare for human exploration of the Red Planet.

Examining the Effects of Extreme Precipitations on the Physical and Cognitive Development of Children

FeaturedNeurosciencePsychology·October 30, 2021

Summary: Extreme “weather shock” experiences that occur during the early stages of life have significant effects on the cognitive, behavioral, and often physical development of a child.

Source: UMass

El Niño-Southern Oscillation (ENSO) and rainfall shocks are often cited as the most important risk factor faced by households in rural, less developed and rain-fed agricultural settings.

Now, research by University of Massachusetts Amherst economist Marta Vicarelli finds that such weather shocks experienced during the early stages of life have significant effects on the cognitive, anthropometric and behavioral indicators of children measured between 2-6 years of age.

In a new paper published online by the journal World Development, Vicarelli and co-author Arturo Aguilar of Instituto Tecnológico Autónomo de México (ITAM) examine the effects that extreme precipitations experienced during the early stages of life have had on the physical and cognitive development of children in poor rural areas of Mexico.

By examining the effects of ENSO-related extreme precipitation shocks that caused floods and impacted the 1998-99 maize harvest seasons, and using geographical variation in precipitation, Vicarelli and Aguilar compared children exposed to the weather shock in early stages of life versus same-aged children not exposed to extreme precipitation.

The researchers found that, on average, children affected between their in-utero development and 2 years of age exhibit 0.06 standard deviations (SDs) lower weight, 0.05 SDs lower height and a higher likelihood of stunting (8.3 percentage points). They also found that language development, working memory and visual-spatial thinking test scores of these children are, 0.19, 0.17 and 0.15 SDs lower than same-aged children not exposed, respectively.https://a95f6ec0ad8322ad519d08713d35ee6f.safeframe.googlesyndication.com/safeframe/1-0-38/html/container.html

The effects are particularly pronounced for children who were 1-2 years old when the shock occurred.

These impacts are equivalent to a three- to four-month delay in development, the researchers note, which could later be exacerbated if not addressed. They note that short- and long-term memory and visual-spatial capabilities during childhood have been proven to be strong predictors of academic and professional achievements later in life, and that stimuli or stressful conditions during critical periods in early life can have permanent consequences into adulthood.

They say that the evidence provided in their new paper will help better understand how the early shocks translate to effects that remain into adulthood.

“Vulnerability to climate extremes is worsening with climate change and it is exacerbated in El Niño and La Niña years,” says Vicarelli, assistant professor of economics and public policy at UMass Amherst.

“The results of our study provide insights on possible socio-economic impacts of climate change in developing countries, particularly in terms of human capital formation. We hope that our results will contribute to the discussion on climate adaptation and disaster risk reduction.”https://a95f6ec0ad8322ad519d08713d35ee6f.safeframe.googlesyndication.com/safeframe/1-0-38/html/container.html

Changes in household food consumption and diet composition induced by the weather shock appear to be key drivers behind the impacts on children’s cognitive and physical development.

Total household income reported two months after the weather extreme event occurred was 32% lower for households living in the exposed regions. This negative income effect from the weather shock persisted at least one year after the event.

Diet composition presented significant changes, as well. The year after the extreme event, households in affected regions reported a 28% contraction in their consumption of animal-origin proteins and a 10% decrease in their consumption of fruits and vegetables.

The researchers note that overall food intake measured in total amount of kilograms and calories was not affected, which suggests that households oriented their food selection toward less nutritious and cheaper items following the event. They believe that this poor nutrition may have negatively affected the children’s cognitive and physical development.

Meanwhile, the area of Mexico that the researchers examined was targeted by one of the most extensively studied anti-poverty governmental programs—PROGRESA—at the time of the shock.

This allowed Vicarelli and Aguilar to examine whether PROGRESA’s cash transfers allowed households to mitigate their vulnerability to ENSO-related weather extremes. They say that their findings of only partial evidence of mitigation from the delivery of PROGRESA and other government programs suggests that, if not addressed promptly and with targeted policies, the cognitive functioning delays induced by climate extremes may not be easily recovered.https://a95f6ec0ad8322ad519d08713d35ee6f.safeframe.googlesyndication.com/safeframe/1-0-38/html/container.html

The timing, targeting and amount of support received could be crucial aspects to at least partially protect cognitive and physical development outcomes for young children after climate-change-related weather shocks, they argue.https://a95f6ec0ad8322ad519d08713d35ee6f.safeframe.googlesyndication.com/safeframe/1-0-38/html/container.html

“As climate change adaptation and disaster risk management have become mainstream in development work, there has been growing international attention to strategies minimizing exposure of vulnerable populations to climate-related extreme events,” Vicarelli says. “Uninsured losses may keep vulnerable populations in poverty or trigger poverty traps.”

The authors note that post-COVID-19 recovery plans currently under development in numerous countries focus on climate resilience, climate mitigation and economic expansion to aid future debt repayment.See also

Auditory NeuroscienceFeaturedNeuroscienceOpen Neuroscience ArticlesJune 2, 2021

Anyone Can Get Super-Hearing

“Our results suggest that in developing countries at high climate risk, climate resilience strategies aimed at reducing vulnerability to weather extremes could benefit children’s physical and cognitive development,” Vicarelli says. “And this would consequently bring long-term socio-economic benefits for society at large.”

About this cognitive development research news

Author: Press Office
Source: UMass
Contact: Press Office – UMass
Image: The image is in the public domainhttps://a95f6ec0ad8322ad519d08713d35ee6f.safeframe.googlesyndication.com/safeframe/1-0-38/html/container.html

Original Research: Closed access.
“El Niño and children: Medium-term effects of early-life weather shocks on cognitive and health outcomes” by Arturo Aguilar and Marta Vicarelli. World Development

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Abstract

El Niño and children: Medium-term effects of early-life weather shocks on cognitive and health outcomes

The fact that shocks in early life can have long-term consequences is well established in the literature.

This paper examines the effects of extreme precipitations on cognitive and health outcomes and shows that impacts can be detected as early as 2 years of age.

Our analyses indicate that negative conditions (i.e., extreme precipitations) experienced during the early stages of life affect children’s physical, cognitive and behavioral development measured between 2 and 6 years of age.

Affected children exhibit lower cognitive development (measured through language, working and long-term memory and visual-spatial thinking) in the magnitude of 0.15 to 0.19 SDs. Lower height and weight impacts are also identified. Changes in food consumption and diet composition appear to be key drivers behind these impacts.

Partial evidence of mitigation from the delivery of government programs is found, suggesting that if not addressed promptly and with targeted policies, cognitive functioning delays may not be easily recovered.

This Is How Many Calories you Burn While You Sleep

Let’s just say that snoozing doesn’t always mean you lose.

BY ROZALYNN S. FRAZIEROCT 30, 2021DAMIRCUDICGETTY IMAGES

You may not think of your time sleeping as an exercise in calorie-burning, but the truth is your body is always burning some no matter what you are doing—and that includes being sprawled out across your bed sleeping. To be clear, the calorie burn is minimal— approximately 40 to 55 calories per hour, and there are several factors that come into play with that number, including how much you weigh. So while it won’t rival your latest HIIT or powerlifting workout, it could net you a nice couple hundred or more, if you are sleeping for at least the minimum number of recommended hours, which the CDC says is about seven.

What determines how many calories you burn while sleeping

Ever heard of resting metabolic rate? It’s the number of calories an individual burns while at rest. “It is essentially the minimum energy required for essential physiological functions keeping us alive,” explains Alex Rothstein, CSCS, coordinator and instructor for the Exercise Science Program at New York Institute of Technology.

“When we sleep, we are the most at rest, so our caloric expenditure is based on this,” he goes on, noting that the factors that influence our caloric expenditure are based on things that affect our metabolism. Those things include the amount of lean body mass you have, whether you worked out that day, and what type of food you eat.ADVERTISEMENT – CONTINUE READING BELOWhttps://9e02461a1896660cdb7f3fb3ac5126e9.safeframe.googlesyndication.com/safeframe/1-0-38/html/container.html

Sleep affects weight in more ways than just nighttime calorie burn

While you are burning calories during sleep, there are other important ways that sleep affects what you weigh. When it comes to keeping the pounds in check, both the quality and quantity of your sleep are important.

A constant lack of Zs wreaks havoc on your hunger hormones, upping the amount of the appetite-stimulating ghrelin and decreasing the appetite-suppressing leptin in the body. “Consuming calories is one compensatory mechanism for an under slept individual,” says MH advisor W. Chris Winter, MD, a neurologist and sleep specialist, and author of sleep books including The Rested Child. In other words, you’re prone to eating more. Not only that, but after just one sleepless night, research reveals that you’re also prone to specifically eating more calorie-dense and high-fat foods.

Sleep affects other weight-regulating hormones as well. “Yes, sleep deprivation, even short term, can result in insulin and glucose imbalances,” says Kuljeet (Kelly) Gill, MD, a sleep medicine specialist at Northwestern Medicine Central DuPage Hospital. Lack of sleep can also affect how balanced cortisol and your thyroid hormones are.RELATED STORYThe 13 Best Pillows for Sleeping Peacefully

Sleep also affects your workout, which could affect your weight

A good night’s rest is critical to all physiological functions, and not getting the right amount can really be detrimental. When it comes to a workout specifically, sleep “influences everything from how you perceive your workout, how tired it is making you, or how focused you are on form, to how much endurance and strength you have,” explains Rothstein. “It then influences how well you recover from the workout in order to adapt and come back stronger and more resilient.”

With all the ways a negative night of slumber can affect you, it’s a must to snooze well. Things like setting a sleep schedule, having a nightly routine (try downloading the Peloton, Calm, Ten Percent Happier or Headspace apps and doing a quickie bedtime meditation); not watching TV in bed and making your room as comfy and cool as possible—you want your room to be about 65 degrees—can all help.

This new $15 Raspberry Pi is like mana for at-home programming projects

It’ll cost you $5 more than its predecessor

https://0cd92a60fa36d8de33ed850e3fc45166.safeframe.googlesyndication.com/safeframe/1-0-38/html/container.htmlSTORY BYIvan Mehta

Raspberry Pi has released a new board called the Zero 2 W — and, excitingly, it costs just $15. It has more than five times more power than its predecessor, thanks to a new quad-core CPU.

This makes it ideal for building small media servers, pet monitors, or any number of similar development projects. Before we talk about how it compares with the Zero W, let’s take a look at its specifications.

Specifications

• Broadcom BCM2710A1, quad-core 64-bit SoC (Arm Cortex-A53 @ 1GHz)
• 512MB LPDDR2 SDRAM
• 2.4GHz IEEE 802.11b/g/n wireless LAN, Bluetooth 4.2, BLE
• 1 × USB 2.0 interface with OTG
• HAT-compatible 40 pin I/O header footprint
• MicroSD card slot
• Mini HDMI port
• Composite video and reset pin solder points
• CSI-2 camera connector
• H.264, MPEG-4 decode (1080p30); H.264 encode (1080p30)
• OpenGL ES 1.1, 2.0 graphics

The previous version of the board only had one ARM-based core clocked at 1Ghz. What’s more, the new iteration also works on 64 bits, rather than sticking to the 32. Improved data processing, here we come.Roast me, dear customerWhy we should embrace the review economyREAD ARTICLE

The new version also supports a H.264 video decoder, so you can process full HD video stream at 30 frames per second.On top of this, the Zero W 2 comes with a new micro USB-based power supply unit (PSU). Even though, it’s a shame we didn’t get a USB-C upgrade.The company is also selling the $5 Zero and $10 Zero W, but has said deliveries of these boards will be delayed due to the global chip shortage. Thankfully though, you can still pick up the Zero W 2 and it’s more powerful. What’s not to like?If you’re getting started with the board, here’s a handy list of projects you can try to create, including a smart speaker, a game console, and a guitar pedal.You can read more technical details about the Raspberry Pi Zero 2 W here. Happy programming and developing, people!

Microscopic Nanotech Color Slides Could Change How We Identify Disease

DAVID NIELD30 OCTOBER 2021

It’s called the NanoMslide: Five years in development, it’s able to work in tandem with a conventional microscope to bring cancer cells out in distinct colors, enabling experts to spot signs of the disease much more easily.

The new technology is based on the physics of plasmons – oscillations in charged particles, such as electrons. Thin layers of silver provide whole fields of free-roaming electrons, which, when stimulated by light, line up in a specific fashion.

Poking tiny, nanosized pores into the silver manipulates the light’s structure, so as it passes up through tissue, certain colors will be selected, producing a spectrum that depends on subtle differences in the sample’s structure and – importantly – its own electron configurations.

Effectively, the microscope slide becomes a sensor, revealing the composition of the cells placed on it through a color-coded light show. It promises to enable disease diagnosis that’s made earlier and quicker than before, without the labor-intensive application of stains that risk damaging samples.

Cancerous cells highlighted under the microscope. (La Trobe University)

“When I first looked at a tissue under the microscope on the NanoMslide, I was incredibly excited,” says biochemist Belinda Parker from La Trobe University in Australia.

“For the first time I saw cancer cells just popping up at me. They were a different color from the surrounding tissue, and it was very easy to distinguish them from surrounding cells.”

Parker and her colleagues describe the difference as going from black and white television to color – so quite a jump. With existing techniques, trying to identify cancer cells under a microscope can be a bit like looking for a needle in a haystack.

The team used a variety of advanced fabrication techniques, some of which have only just been developed, to produce their slides. Once the technology is scaled up, it should prove helpful in a range of medical and non-medical settings.

These nanotech slides require much less preparation time than existing techniques, and results can be obtained in as little as 10 minutes. In time-critical situations – deciding which parts of a tumor to remove during surgery, for example – that’s hugely beneficial.

“Current approaches to tissue imaging often rely on staining or labeling cells in order to render them visible under the microscope,” says physicist and chemist Brian Abbey, also from La Trobe University.

“Even with staining or labeling, it can be challenging for pathologists to detect cancer cells, with the risk that some samples are misdiagnosed, particularly during the very early stages of disease.”

As effective as the NanoMslide is, the researchers still aren’t exactly sure what distinguishes the different colors: It could be the proteins in the cells, they suggest, or something to do with the cell skeletons, or how the cells are organized.

A study has already been completed showing how the nanotechnology improves the process of picking out early-stage breast cancer from benign lesions, using both human tissue and a mouse model: visually, the cancer cells showed “good differentiation” from other cells, the researchers report.

The team is now confident that the NanoMslide can be adapted to look for a variety of types of cancers and even different diseases altogether. Its creators are currently working to get the tech into a form that can be used commercially.

“Our vision is to extend our technology to assist the diagnosis of a range of other cancers by analyzing all sorts of tissue sections, as well as use in plant biology and agriculture,” says Abbey.

The research has been published in Nature.

ON BUILD AN OPEN SOURCE-HARDWARE ALLWINNER D1S RISC-V LINUX SBC FOR UNDER $10

Build an open source-hardware Allwinner D1s RISC-V Linux SBC for under $10

We covered Allwinner D1s RISC-V processor with 64MB built-in RAM a few days ago, and we’ve just found out about Xassette-Asterisk, an open-source hardware board based on the processor that runs Linux (OpenWrt) and is said to cost less than $10 to make.

This is significantly cheaper than the Allwinner D1 based Nezha RISC-V Linux SBC currently sold for a little over $100, a rather poor value. The cheaper board will not quite have the same applications with just 64 MB RAM and no HDMI, but it could be great for projects requiring a camera and/or a display, audio interfaces, plus some I/Os.

Xassette-Asterisk specifications:

• SoC – Allwinner D1s single-core 64-bit RISC-V processor @ 1.008 GHz with 64MB DDR2
• Storage – MicroSD card slot, 32 MBit SPI flash (W25Q32 – U2 on the board)
• Display I/F – 40-pin LCD connector, 6-pin touch panel interface, backlight power
• Camera I/F – 24-pin MIPI CSI connector
• Audio – 3.5mm headphone+mic jack, 3.5mm Line-in jack
• USB – 1x  USB Type-C OTG port, 1x USB Type-C host port
• Expansion – 34-pin GPIO header which should include SPI, I2C, UART, PWN, DAC, ADC, IR Tx, R, as well as  power signals (5V, 3.3V, and GND)
• Debugging – 3-pin UART header for serial console
• Misc – Reset button
• Power Supply
  • 5V via USB-C port
  • 3.3V via pin header (note: USB ports won’t work with this method)
• Dimensions – 56 x 56mm (2-layer PCB layout)

Some of the chips, the Reset button, and the microSD card socket are missing from the photos above, but we should expect those to be soldered to the board in the final version. You’ll find the KiCad and PNG schematics on Github. I used that to derive the specifications myself since they were not published at the time of writing this article.

There’s no software on that repository, but the Hackaday.io project shows the boards running the OpenWrt based Tina Linux with kernel 5.4.61, and Whycan has documentation and the SDK for Allwinner D1/D1s/F133 RISC-V processors.

The open-source hardware Allwinner D1s board is not for sale, so you may be better off waiting for MangoPi-MQ1 SBC that’s expected to become available next month on Taobao and Seeed Studio, and an expected price tag of around $10. If you’d like to build your own board, Allwinner D1s (aka F133) processor is sold for 35 RMB (or about $5.5) in single units on Taobao. I had to register with a mobile number to access the page, so here’s a screenshot for your reference.

Analyzing technologies’ climate efficiency in removing carbon dioxide from the atmosphere

by University of Freiburg

Technologies for the removal of carbon dioxide (CO₂) from the atmosphere (direct air capture, or DAC for short) are already in use, but neither their actual benefits for climate protection nor their other environmental impact have yet to be investigated.

A research team led by Kavya Madhu and Prof. Dr. Stefan Pauliuk from the University of Freiburg (Faculty of Environment and Natural Resources) has now analyzed the carbon footprint of these technologies. To do so, they determined for two common DAC processes—one at high and one at low temperature for capturing CO₂—how high their energy input, CO₂ emissions and other consumption factors are to extract one ton, one megaton and one gigaton of CO₂ from the atmosphere and inject it into deep soil layers. They also compared these values to key existing technologies and measures for CO₂ reduction, such as e-mobility and heat pumps. “The low-temperature process for CO₂ extraction proved to be surprisingly efficient,” says Kavya Madhu, “for one ton of CO₂ extraction, for example, 0.3 tons of CO₂ are currently emitted in the energy and heat supply required for this, and as little as 0.15 tons if low- CO₂ electricity is used. The resulting net CO₂ extraction of 0.7-0.85 tons is comparable to the CO₂ savings from using the same amount of energy for electric cars instead of gasoline-powered cars. They published the results of their study, “Understanding environmental trade-offs and resource demand of direct air capture technologies through comparative life-cycle assessment,” in the journal Nature Energy.

“Several factors for long-term storage are still unknown”

Extraction technologies first bring ambient air into contact with a substance that absorbs the CO₂ from the air. In a second step, the captured CO₂ is released again in high concentration by heating and then liquefied. Energy expenditures and emissions for the CO₂ extraction processes arise in particular from the necessary generation of ventilation, chemical reactions and heating, as well as the injection of the extracted CO₂ into deep soil layers. However, according to Stefan Pauliuk, “Several factors for long-term CO₂ storage are still unknown or difficult to determine, such as the dynamically evolving CO₂ storage capacity of rocks.”

For their study, the team determined the efficiency of CO₂ extraction technologies over their life cycle using a detailed life cycle assessment in OpenLCA software. They calculated the environmental impact of providing the materials and energy needed to build the plants and capture and inject CO₂. For comparison with other technologies and CO₂ reduction measures, they used existing data from various literature sources, aligned them, and performed their own process modeling to ensure completeness and consistency.

“Given that CO₂ extraction is already comparatively efficient, DAC technologies are likely to play a long-term role in climate mitigation as a complement, not a replacement,” Madhu and Pauliuk conclude. “Given the uncertainty of actual scalability, the risks associated with CO₂ storage in rock, and the early-stage development of DAC technologies, the use of already established and similarly climate-efficient technologies such as battery-operated vehicles and heat pumps remains urgent.”

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Explore furtherEffectively removing carbon dioxide from the atmosphere

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More information: Kavya Madhu et al, Understanding environmental trade-offs and resource demand of direct air capture technologies through comparative life-cycle assessment, Nature Energy (2021). DOI: 10.1038/s41560-021-00922-6Journal information:Nature EnergyProvided by University of Freiburg

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The 8 Sleep Trackers that Will Assure You Get the Beauty Sleep You Need

• How to choose
• How we chose
• Our picks
• Takeaway

We include products we think are useful for our readers. If you buy through links on this page, we may earn a small commission. Here’s our process.

A quick look at the best sleep trackers

• Best under-the-mattress tracking pad: Withings Sleep Tracking Pad
• Best wearable device: The Oura ring
• Best for tracking other health concerns: Sleepon Go2sleep Tracker
• Best for couples: Tempur-Pedic Sleeptracker
• Best smartwatch: Fitbit Sense Smartwatch
• Best fitness tracker: Garmin Vívosmart 4 Activity Tracker
• Best for sleep coaching: Beautyrest SleepTracker
• Best contactless option: Sleepscore Labs Sleepcore Max

If you find yourself waking up tired and groggy each morning, you might not be getting enough quality sleep. Getting a good night’s rest can help fight off illness, keep you alert and focused throughout the day, and lower the risk of cancer, diabetes, and coronary heart disease.

It can be hard to determine how much sleep you’re getting each night, which is why it may be helpful to invest in a sleep tracker. Sleep trackers monitor your sleep patterns for a clearer picture of how much quality sleep you’re getting. Once that data is collected, you’ll be able to make adjustments to improve the quality of sleep you’re getting.

Choosing a sleep tracker can be tricky since there are so many options. To help you decide, we compiled a list of the best sleep trackers on the market.

How to choose

Type

There are two main types of sleep trackers on the market: wearables (rings, watches, bracelets, etc.) and under-the-mattress trackers. It really depends on what you’re comfortable with. Some users find wearables to be irritating at night, while others like wearables because they often provide more than just sleep data.

Number of sleepers

If you want a sleep tracker that tracks the sleep of both you and your partner, you may want to look for an under the mattress tracker that comes with two sensors.

Smart alarm

Smart alarms wake you up at the optimal time each morning by using data to figure out when you’re in the middle of light sleep. Some wearable devices also have vibrating alarms which are less jarring than a loud noise and don’t disturb your partner.

Other specs

Most fitness trackers come with sleep analytics, but it depends on whether or not you’re looking for something that’s designed specifically to be a sleep tracker. Fitness wearables can perform other health-related functions like activity tracking, menstrual cycle tracking, GPS coaching, etc. These features may make your device more versatile, but they often increase the price-point.

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How we chose

We took choosing a sleep tracker seriously — and we put in the leg work to find the best choices out there. The sleep trackers chosen here are the latest on the market, featuring the most innovative technology.

We also looked at company reputation and transparency, company policy, and customer reviews to make sure we only recommend trackers that people actually love.

Pricing guide

• $ = under $100
• $$ = $100-$200
• $$$ = over $200

Healthline’s picks of the 8 best sleep trackers of 2021

Best under-the-mattress tracking pad

Withings Sleep Tracking Pad

• Price: $
• Type: Under mattress
• Battery life: Plugin
• Pro: Compatible with Amazon Alexa
• Con: Some reviewers complain that the pad isn’t wide enough for king beds to track when you’ve rolled over

Wearable devices can be bothersome to many when sleeping, which is why we love this sleep tracking pad from Withings. The pad goes underneath your mattress and detects:

• heart rate
• snoring and sleep cycles
• breathing disturbances
• heavy and REM sleep cycles
• when you wake up

All of this data can be found on the Withings app on your phone. You also get a sleep score each night which helps you make improvements to your sleep hygiene. Bonus? There’s a sensor that can act as a switch to control lights, the thermostat, and more.SHOP NOW AT WITHINGS

Best wearable device

​​The Oura ring

• Price: $$$
• Type: Wearable
• Battery life: 7 days
• Size: You get a free sizing kit when you place your order
• Pro: Connects to Google Fit and Apple Health
• Con: Can be slow to sync at times, expensive

Oura is ​​a custom smart ring that records your heart rate, heart rate variability, breathing rate, skin temperature, and more. The ring uses an infrared LED sensor to produce a sleep score and gives tailored advice to improve the quality of your sleep.

For those who dislike wearables, users report that they don’t even notice that they’re wearing it at nighttime and that it’s super-comfortable and lightweight.SHOP NOW AT OURA

Best for tracking other health concerns

Sleepon Go2sleep Tracker

• Price: $
• Type: Wearable
• Battery life: 24 hours
• Pro: Lightweight
• Con: Not the best for those struggling with sleep apnea as it doesn’t measure airflow and rate of respiration

This silicone ring measures your sleep duration and quality, heart rate, blood oxygen level, and more. If you’re struggling with other health concerns, this ring will warn you when it detects abnormal heart and oxygen levels.

The ring can also sync with the iOS Health app to give you suggestions based on other trackable habits.SHOP NOW AT SLEEPON

Best for couples

Tempur-Pedic Sleeptracker

• Price: $$$
• Type: Under mattress
• Battery life: Plugged in
• Pro: Has an alarm that can wake you during your lightest sleep phase
• Con: Expensive

This sensor slides under your mattress to provide you with custom sleep insights on its Sleeptracker-AI app. It’s compatible with any mattress, not just Tempur-Pedic, and can track the sleep of two people, which makes it excellent for couples.

An AI sleep coach looks at your data and offers easy-to-implement sleep tips based on your sleep behavior so that you (and your partner) can sleep deeper.SHOP NOW AT TEMPUR-PEDIC

Best smartwatch

Fitbit Sense Smartwatch

• Price: $$$
• Type: Wearable
• Battery life: 6 days
• Size: Small and Large bands available
• Pro: You can connect with other Fitbit users
• Con: May have too many features for some users

If you’re looking to track more than just sleep activity, you might want to invest in a smartwatch.

This one from Fitbit comes with a pedometer, voice assistant, Bluetooth calls and texts, Fitbit pay, menstrual health tracking, and more. The sleep app offers personalized recommendations to improve your sleep quality, and the watch has a smart alarm that wakes you up at the optimal time each morning.SHOP NOW AT AMAZON

Best fitness tracker

Garmin Vívosmart 4 Activity Tracker

• Price: $$
• Type: Wearable
• Battery life: 7 days
• Pro: Vibrating alarm clock option
• Con: Doesn’t give a lot of advice as to how to sleep better

Unlike other fitness trackers, the Vivosmart 4 is sleek and discreet, making it perfect for those who dislike the bulkiness of most wearables. It has a small touchscreen display and measures your sleep cycle, blood oxygen level, stress level, and body recovery from workouts.

More specifically, it tracks your light, deep, and REM stages of sleep along with movement throughout the night so that you can get a clear picture of how you’re sleeping.SHOP NOW AT AMAZON

Best for sleep coaching

Beautyrest SleepTracker

• Price: $
• Type: Under Mattress
• Battery life: Plug In
• Pro: Compatible with Amazon Alexa
• Con: Requires strong internet connection

This contactless sleep tracker rests under any brand of mattress to provide data for up to two sleepers. It works to monitor your heart rate, track sleep, observe your respiratory rate, and track your body movements during the night.

After a few nights of learning your sleep patterns, the app is able to provide you with customized sleep coaching. But users report that it’s unable to distinguish between light sleep and lying still in bed.SHOP NOW AT AMAZON

Best contactless option

Sleepscore Labs Sleepcore Max

• Price: $$
• Type: Contactless
• Battery life: Plug In
• Pro: Contactless
• Con: Needs to be set up properly for accuracy

This contactless sleep monitor can track and monitor your patterns of sleep without having to be placed underneath your mattress or anywhere on your bed. The Sleepscore Max also monitors the ambient lighting, temperatures, and other environmental factors in your room that may affect your sleep quality.

Just remember that the device needs to sit higher than the top of your mattress and should be placed no more than 3.9 feet away for the best accuracy.SHOP NOW AT SLEEPSCORE LABS

Takeaway

Sleep trackers are equipped with tools and features that can help you make adjustments to wake up well-rested. They monitor things like sleep duration and quality, heart rate, blood oxygen level.

A variety of options are available, and each one includes a unique set of features and functions.

When shopping for a sleep tracker, consider factors like the type, available features, sleep-specific options, and price.

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Iman Balagam is a writer based in Houston, Texas. When she’s not laughing at her own jokes, or buying overpriced chia pudding, she can be found reading fiction novels, catching a spin class, doomscrolling through TikTok, or waiting for her delayed Spirit flight to board. You can see more of her work on her website.

Pyboard (MicroPython): Review the Specs

by Jackson O’Connell
Published Oct 28, 2021ADVERTISEMENT

The Pyboard is a single-board computer running MicroPython OS and offering many ports and interface options. Read on to learn more!CONTENTS

• Features
• An Alternative
• Specifications
• Where to Buy

Asingle-board computer (SBC) is an entire computer built on a single circuit board. Typically, SBCs feature as many ports, chips, and as much computing power as they can, allowing for many uses, especially small projects like network-attached storage (NAS), controlling a robot, or even hosting a remote 3D printer server like OctoPrint.

The Raspberry Pi is often considered a standard among SBCs, as the Pi was a pioneer (no pun intended) in helping makers complete small projects at an affordable price. But more recently, many other SBCs with enhanced features and niche applications have emerged, making the market much more competitive. These boards range in capability, with some offering more interface options, ports, computing power, and software compatibility than others.

One of these newer-generation SBCs is the Pyboard, made by MicroPython and running the operating system (OS) of the same name. Python is a popular high-level programming language with many applications, from numeric computing to web development and even 3D modeling. The MicroPython OS is a fork of Python 3, optimized to run on an SBC like the Pyboard. The Pyboard is a compact yet powerful SBC with more than enough interface options, ports, and sensors for many small projects, making it a great tool for makers.

In this article, we’ll be reviewing the specs of the Pyboard v1.1, discussing its features, uses, price, and more! For reference, there are only a handful of differences between the v1.1 and the v1.0, including that the v1.1 has a crystal speed of 12 MHz (increased from 8 MHz), so most of the information in this article applies to both versions.PYBOARD (MICROPYTHON): THE BASICS

Features

In this section, we’ll dive into a few unique features of the MicroPython Pyboard, focusing on its OS, ports, interface options, and sensors.

Operating System

The first significant feature of the Pyboard is its compatibility with MicroPython OS. MicroPython is a stripped-back version of Python 3 that requires less computing power and is optimized for use on small SBCs like the Pyboard v1.1.

MicroPython requires only 256 KB of code space and 16 KB of RAM, which the Pyboard easily meets with its 1,024 KB of flash space and 192 KB of memory (RAM). The Pyboard also has a 168-MHz Cortex M4 processor (CPU), which runs on an STM 32-bit framework.

MicroPython OS has some advanced features like arbitrary precision integers, list comprehension, generators, and more. Despite being a relatively powerful operating system, MicroPython can comfortably run on the Pyboard without even coming close to meeting the computing power limits.

Ports

The range of ports is another impressive feature of the Pyboard, given its small size. To start, the board has a Micro-USB port, which it uses for power along with the onboard 3.3-V power voltage regulator. For storage space, the board contains a microSD card slot on the back that supports standard and high-capacity SD cards.

While these ports are useful, it’s the general-purpose input and output ports (GPIO) that really take the Pyboard to the next level because it has 30! These ports come on the board as solderable pads, but you can also get an alternative version of the board with pin headers to use Dupont cables instead of soldering. The GPIO ports allow you to control electronic circuits, meaning you can control servos, LCD screens, sensors, and more.

Interface Options & Sensors

Lastly, the interface options of the board include the ways you can communicate with the Pyboard. The Pyboard has a few ways to interact with it, including the two buttons located near the board’s processing chip. One button is for resetting the board, while the other one is labeled as “USR” for “user” and can be programmed to activate or perform certain tasks when pressed.

There are also four LEDs on the Pyboard, which light up blue, yellow, green, and red, respectively. You can program these to illuminate when certain tasks are performed or the sensors detect something.

The Pyboard can respond to its accelerometer and its clock. The board has a real-time clock that can run time-sensitive Python programs like an alarm clock or even a wait script in a larger program.

The accelerometer is a 3-axis sensor that measures acceleration on the X-, Y-, and Z-axes. The sensor uses its acceleration findings to determine the board’s angle and position on the three axes. This feature could be useful for certain projects like a remote-controlled robot that needs to know what angle to move at.ADVERTISEMENThttps://googleads.g.doubleclick.net/pagead/ads?us_privacy=1—&client=ca-pub-8044370825796563&output=html&h=600&slotname=9222545752&adk=41103614&adf=3895240216&pi=t.ma~as.9222545752&w=300&lmt=1635422585&rafmt=12&psa=1&format=300×600&url=https%3A%2F%2Fall3dp.com%2F2%2Fmicropython-pyboard-review-specs%2F&flash=0&wgl=1&uach=WyJtYWNPUyIsIjEwLjExLjYiLCJ4ODYiLCIiLCI5NS4wLjQ2MzguNTQiLFtdLG51bGwsbnVsbCwiNjQiXQ..&tt_state=W3siaXNzdWVyT3JpZ2luIjoiaHR0cHM6Ly9hdHRlc3RhdGlvbi5hbmRyb2lkLmNvbSIsInN0YXRlIjo3fV0.&dt=1635626022724&bpp=30&bdt=19647&idt=30&shv=r20211026&mjsv=m202110260101&ptt=9&saldr=aa&abxe=1&cookie=ID%3D843c006e8ad44fb5-2205c1ece7cb001e%3AT%3D1635626006%3AS%3DALNI_MYgM0t7Wqw7jHD29_7jOSqJ1_4WWQ&prev_fmts=0x0%2C1679x900&nras=2&correlator=837522476496&frm=20&pv=1&ga_vid=1222207961.1635626005&ga_sid=1635626006&ga_hid=1358138662&ga_fc=1&u_tz=-420&u_his=1&u_h=1050&u_w=1680&u_ah=980&u_aw=1680&u_cd=24&adx=1379&ady=1102&biw=1679&bih=900&scr_x=0&scr_y=328&eid=21066429%2C31063300%2C31063307%2C21065725%2C21067496&oid=2&pvsid=1290882997075729&pem=669&ref=https%3A%2F%2Fnews.google.com%2F&eae=0&fc=1920&brdim=0%2C23%2C0%2C23%2C1680%2C23%2C1679%2C980%2C1679%2C900&vis=1&rsz=%7C%7CeoE%7C&abl=CS&pfx=0&fu=256&bc=31&ifi=4&uci=a!4&fsb=1&xpc=Zl1UYO9yLn&p=https%3A//all3dp.com&dtd=108ADVERTISEMENTPYBOARD (MICROPYTHON): THE BASICS

An Alternative

The Pyboard has some pretty impressive features that make it a powerful SBC for its miniature size and low price. But how does it stack up against the competition? To find out, let’s compare it to the Raspberry Pi Zero W, a similar SBC in size and capability but generally less expensive.

To start, the Pyboard works with MicroPython while the Zero W runs Raspberry Pi’s default Raspberry Pi OS. These operating systems are both great options, but Raspberry Pi OS has the advantage of the larger organization and community backing it. However, if you’re used to working with Python, the Pyboard running MicroPython is still a great choice.

Both boards have many GPIO ports, with the Pyboard’s respectable 30 being overtaken by the Pi Zero W’s 40. This means the Pi Zero W has more options for connecting to additional hardware.

On the bright side, though, the Pyboard has four different-colored lights that you might be able to use in small projects. Moreover, the Pyboard also has a 3-axis sensor that determines the board’s angle and motion, while the Pi Zero W would require hardware attached on top (a.k.a. a HAT) to add this feature.

Both SBCs have a Micro-USB cable and a microSD card slot, but the Pi Zero W has two Micro-USB ports, a Mini-HDMI port, and a ribbon-cable camera port. Once again, these additional features make the Raspberry Pi Zero W a strong option for small maker projects. The Pi Zero W also has more RAM and flash space than the Pyboard, a Wi-Fi module for a wireless internet connection, and it even has a Bluetooth connection chip.

Despite these features, the Pyboard is still an excellent SBC for its size and price. The Pyboard is a great option if you want to create programs for small projects using the MicroPython operating system without changing your OS after getting your board and do not need wireless connectivity. Also, the Pyboard has a 3-axis sensor that can be used to measure your board’s position and angle, which may come in handy for certain projects.ADVERTISEMENTADVERTISEMENTPYBOARD (MICROPYTHON): THE BASICS

Specifications

Below is a list of specifications for the Pyboard:

• CPU: Arm 32-bit 168-MHz Cortex-M4
• Memory: 192 KB RAM
• Flash: 1 MB flash
• Ports: Micro-USB, microSD, 30x GPIO
• Interface options: Reset switch, user switch, 4 LEDs
• Sensors: 3-axis accelerometer
• Clock: With battery backup
• Compatible OS: MicroPython (based on Python 3)
• Power: 3.6-16 V; onboard 3.3-V regulator supplying up to 250 mA
• Dimensions: 43.18 x 41.91 mm

ADVERTISEMENThttps://googleads.g.doubleclick.net/pagead/ads?us_privacy=1—&client=ca-pub-8044370825796563&output=html&h=600&slotname=6600044704&adk=2358728849&adf=1283342108&pi=t.ma~as.6600044704&w=300&lmt=1635422585&rafmt=12&psa=1&format=300×600&url=https%3A%2F%2Fall3dp.com%2F2%2Fmicropython-pyboard-review-specs%2F&flash=0&wgl=1&uach=WyJtYWNPUyIsIjEwLjExLjYiLCJ4ODYiLCIiLCI5NS4wLjQ2MzguNTQiLFtdLG51bGwsbnVsbCwiNjQiXQ..&tt_state=W3siaXNzdWVyT3JpZ2luIjoiaHR0cHM6Ly9hdHRlc3RhdGlvbi5hbmRyb2lkLmNvbSIsInN0YXRlIjo3fV0.&dt=1635626124027&bpp=4&bdt=120946&idt=4&shv=r20211026&mjsv=m202110260101&ptt=9&saldr=aa&abxe=1&cookie=ID%3D843c006e8ad44fb5-2205c1ece7cb001e%3AT%3D1635626006%3AS%3DALNI_MYgM0t7Wqw7jHD29_7jOSqJ1_4WWQ&prev_fmts=0x0%2C1679x900%2C300x600&nras=2&correlator=837522476496&frm=20&pv=1&ga_vid=1222207961.1635626005&ga_sid=1635626006&ga_hid=1358138662&ga_fc=1&u_tz=-420&u_his=1&u_h=1050&u_w=1680&u_ah=980&u_aw=1680&u_cd=24&adx=1379&ady=7250&biw=1679&bih=900&scr_x=0&scr_y=4561&eid=21066429%2C31063300%2C31063307%2C21065725%2C21067496&oid=2&psts=AGkb-H9A81gHEaheNzEtwyJNNhuJq824VwAyYgsks32P-8LN8ZvAsGU4H4s2Wp4juI8qZ1l1zIje2OyvT2xjKQ&pvsid=1290882997075729&pem=669&ref=https%3A%2F%2Fnews.google.com%2F&eae=0&fc=1920&brdim=0%2C23%2C0%2C23%2C1680%2C23%2C1679%2C980%2C1679%2C900&vis=1&rsz=%7C%7CeoEbr%7C&abl=CS&pfx=0&fu=256&bc=31&ifi=8&uci=a!8&btvi=1&fsb=1&xpc=wnqwq0ncpj&p=https%3A//all3dp.com&dtd=27ADVERTISEMENThttps://googleads.g.doubleclick.net/pagead/ads?us_privacy=1—&client=ca-pub-8044370825796563&output=html&h=250&slotname=5279987549&adk=3677268602&adf=1062897541&pi=t.ma~as.5279987549&w=970&lmt=1635422585&rafmt=12&psa=1&format=970×250&url=https%3A%2F%2Fall3dp.com%2F2%2Fmicropython-pyboard-review-specs%2F&flash=0&wgl=1&uach=WyJtYWNPUyIsIjEwLjExLjYiLCJ4ODYiLCIiLCI5NS4wLjQ2MzguNTQiLFtdLG51bGwsbnVsbCwiNjQiXQ..&tt_state=W3siaXNzdWVyT3JpZ2luIjoiaHR0cHM6Ly9hdHRlc3RhdGlvbi5hbmRyb2lkLmNvbSIsInN0YXRlIjo3fV0.&dt=1635626137641&bpp=6&bdt=134559&idt=6&shv=r20211026&mjsv=m202110260101&ptt=9&saldr=aa&abxe=1&cookie=ID%3D843c006e8ad44fb5-2205c1ece7cb001e%3AT%3D1635626006%3AS%3DALNI_MYgM0t7Wqw7jHD29_7jOSqJ1_4WWQ&prev_fmts=0x0%2C1679x900%2C300x600%2C300x600&nras=2&correlator=837522476496&frm=20&pv=1&ga_vid=1222207961.1635626005&ga_sid=1635626006&ga_hid=1358138662&ga_fc=1&u_tz=-420&u_his=1&u_h=1050&u_w=1680&u_ah=980&u_aw=1680&u_cd=24&adx=355&ady=8311&biw=1679&bih=900&scr_x=0&scr_y=5614&eid=21066429%2C31063300%2C31063307%2C21065725%2C21067496&oid=2&psts=AGkb-H9A81gHEaheNzEtwyJNNhuJq824VwAyYgsks32P-8LN8ZvAsGU4H4s2Wp4juI8qZ1l1zIje2OyvT2xjKQ%2CAGkb-H90l9dc7swvDPNxUmpsWDV-YpHtG4saciXl_p1sSkRRsSsLdhM0QO-E3vTNTeo-p8oHW2Z0G0R-t0c&pvsid=1290882997075729&pem=669&ref=https%3A%2F%2Fnews.google.com%2F&eae=0&fc=1920&brdim=0%2C23%2C0%2C23%2C1680%2C23%2C1679%2C980%2C1679%2C900&vis=1&rsz=%7C%7CeoEbr%7C&abl=CS&pfx=0&fu=256&bc=31&ifi=9&uci=a!9&btvi=2&fsb=1&xpc=2mnv3Y8plz&p=https%3A//all3dp.com&dtd=22PYBOARD (MICROPYTHON): THE BASICS

Where to Buy

You can purchase a Pyboard from one of these online retailers:MICROPYTHON PYBOARD V1.1

COMMISSIONS EARNEDCheck price atOKdoAmazonAliExpress

Researchers discover another way to sequester lead in perovskite solar cells

by National Renewable Energy Laboratory

Scientists at the National Renewable Energy Laboratory (NREL) and Northern Illinois University (NIU) have successfully prevented lead from escaping damaged perovskite solar cells. The research effort is their latest work in addressing concerns about potential lead toxicity.

The light-absorbing layer in perovskite solar cells contains a small amount of lead. Simply encapsulating solar cells does not stop lead from leaking if the device were to become damaged by severe weather conditions, such as a hailstorm. Instead, chemical absorption holds the key.

The researchers report being able to capture more than 99.9% of leakage. Their findings, in an article titled “On-device lead absorbing tapes for sustainable perovskite solar cells,” appears in the journal Nature Sustainability.

The authors are Fei Zhang, Jinhui Tong, and Kai Zhu of NREL; and Xun Li, Jianxin Wang, and Tao Xu of NIU.

“It is valuable to develop an approach that can be applied to various perovskite solar cell configurations,” Zhu said.

Zhu and some of the same researchers in 2020 reported successful experiments in sequestering lead should a perovskite cell become damaged. They developed lead-absorbing films, applied them to the two sides of a cell, and then smashed them with a hammer and slashed them with a knife. The damaged cell was then immersed in water. The scientists found the films prevented more than 96% of the lead from leaking into the water.

Researchers elsewhere followed up on the lead concern and developed a resin that could be incorporated into a perovskite solar cell. But, as the NREL and NIU scientists noted, “These additional modifications could complicate the device fabrication and configuration and potentially limit device performance and scale-up.”

Instead, the authors noted in the paper, a better proposition is to develop durable and highly efficient lead-absorbing components that can be “conveniently mounted” onto the perovskite solar cell as an accessory.

The NREL and NIU scientists believe they have found a solution in using a tape-like chemical absorption approach that can be readily installed on both sides of a perovskite solar cell. In a series of tests, the tapes captured almost all of the lead leakage without compromising the cell’s performance and operation. The tapes were made of a standard solar ethylene vinyl acetate (EVA) film and a pre-laminated di(2-ethylhexyl) methanediphosphonic acid layer.

After damaging the perovskite solar cells, the scientists conducted a series of tests to quantify how much lead would escape into water. In one experiment, the concentration of lead in water that fell on the damaged device averaged about 19.14 parts per million. The tape brought that figure down to 2.13 parts per billion. To put this figure in context, the Environmental Protection Agency considers water safe to drink if the lead content is less than 15 parts per billion.

“Since EVA has been extensively used as a cost-effective and durable encapsulating material for silicon-based solar panels, the integration of lead-absorbing materials with EVA provides an industrially ready and stand-alone component to facilitate the future market adoption of perovskite solar cells,” Xu said.

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Explore furtherScientists find a way to stabilize a promising material for solar panels

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More information: Xun Li et al, On-device lead-absorbing tapes for sustainable perovskite solar cells, Nature Sustainability (2021). DOI: 10.1038/s41893-021-00789-1Journal information:Nature SustainabilityProvided by National Renewable Energy Laboratory