Category Archives: environment

Honey-based neuromorphic chips for brainlike computers?

Photo by Mariana Ibanez on Unsplash Courtesy Washington State University

An April 5, 2022 news item on Nanowerk explains the connection between honey and a neuromorphic (brainlike) computer chip, Note: Links have been removed,

Honey might be a sweet solution for developing environmentally friendly components for neuromorphic computers, systems designed to mimic the neurons and synapses found in the human brain.

Hailed by some as the future of computing, neuromorphic systems are much faster and use much less power than traditional computers. Washington State University engineers have demonstrated one way to make them more organic too.

In a study published in Journal of Physics D (“Memristive synaptic device based on a natural organic material—honey for spiking neural network in biodegradable neuromorphic systems”), the researchers show that honey can be used to make a memristor, a component similar to a transistor that can not only process but also store data in memory.

An April 5, 2022 Washington State University (WSU) news release (also on EurekAlert) by Sara Zaske, which originated the news item, describes the purpose for the work and details about making chips from honey,

“This is a very small device with a simple structure, but it has very similar functionalities to a human neuron,” said Feng Zhao, associate professor of WSU’s School of Engineering and Computer Science and corresponding author on the study.“This means if we can integrate millions or billions of these honey memristors together, then they can be made into a neuromorphic system that functions much like a human brain.”

For the study, Zhao and first author Brandon Sueoka, a WSU graduate student in Zhao’s lab, created memristors by processing honey into a solid form and sandwiching it between two metal electrodes, making a structure similar to a human synapse. They then tested the honey memristors’ ability to mimic the work of synapses with high switching on and off speeds of 100 and 500 nanoseconds respectively. The memristors also emulated the synapse functions known as spike-timing dependent plasticity and spike-rate dependent plasticity, which are responsible for learning processes in human brains and retaining new information in neurons.

The WSU engineers created the honey memristors on a micro-scale, so they are about the size of a human hair. The research team led by Zhao plans to develop them on a nanoscale, about 1/1000 of a human hair, and bundle many millions or even billions together to make a full neuromorphic computing system.

Currently, conventional computer systems are based on what’s called the von Neumann architecture. Named after its creator, this architecture involves an input, usually from a keyboard and mouse, and an output, such as the monitor. It also has a CPU, or central processing unit, and RAM, or memory storage. Transferring data through all these mechanisms from input to processing to memory to output takes a lot of power at least compared to the human brain, Zhao said. For instance, the Fugaku supercomputer uses upwards of 28 megawatts, roughly equivalent to 28 million watts, to run while the brain uses only around 10 to 20 watts.

The human brain has more than 100 billion neurons with more than 1,000 trillion synapses, or connections, among them. Each neuron can both process and store data, which makes the brain much more efficient than a traditional computer, and developers of neuromorphic computing systems aim to mimic that structure.

Several companies, including Intel and IBM, have released neuromorphic chips which have the equivalent of more than 100 million “neurons” per chip, but this is not yet near the number in the brain. Many developers are also still using the same nonrenewable and toxic materials that are currently used in conventional computer chips.

Many researchers, including Zhao’s team, are searching for biodegradable and renewable solutions for use in this promising new type of computing. Zhao is also leading investigations into using proteins and other sugars such as those found in Aloe vera leaves in this capacity, but he sees strong potential in honey.

“Honey does not spoil,” he said. “It has a very low moisture concentration, so bacteria cannot survive in it. This means these computer chips will be very stable and reliable for a very long time.”

The honey memristor chips developed at WSU should tolerate the lower levels of heat generated by neuromorphic systems which do not get as hot as traditional computers. The honey memristors will also cut down on electronic waste.

“When we want to dispose of devices using computer chips made of honey, we can easily dissolve them in water,” he said. “Because of these special properties, honey is very useful for creating renewable and biodegradable neuromorphic systems.”

This also means, Zhao cautioned, that just like conventional computers, users will still have to avoid spilling their coffee on them.

Nice note of humour at the end. There are a few questions, I wonder if the variety of honey (clover, orange blossom, blackberry, etc.) has an impact on the chip’s speed and/or longevity. Also, if someone spilled coffee and the chip melted and a child decided to lap it up, what would happen?

Here’s a link to and a citation for the paper,

Memristive synaptic device based on a natural organic material—honey for spiking neural network in biodegradable neuromorphic systems. Brandon Sueoka and Feng Zhao. Journal of Physics D: Applied Physics, Volume 55, Number 22 (225105) Published 7 March 2022 • © 2022 IOP Publishing Ltd

This paper is behind a paywall.

Citizen science, empowerment, and global challenges

An August 25, 2022 news item on phys.org suggests that citizen science is becoming a more important component in scientific endeavours, Note: Links have been removed,

Citizen science is increasingly recognized as an important vehicle for democratizing science and promoting the goal of universal and equitable access to scientific data and information. IIASA [International Institute for Applied Systems Analysis] researchers actively contribute to the development of this scientific approach and have recently published a primer aimed at both established and aspiring practitioners of citizen science to highlight key issues and how to address them.

Citizen science has a long history and interested volunteers have participated in scientific inquiry for centuries, leading to some of the most extensive datasets and sources of information on among others, public health, pollution monitoring, and ecology and biodiversity tracking. Today, it offers unique opportunities to join science and research across the globe, empowering people to participate in the scientific process, to gather and share data and information, and to be equipped to contribute to collective action to address important challenges that we face locally and globally today.

An August 25, 2022 International Institute for Applied Systems Analysis (IIASA) press release (also on EurekAlert), which originated the news item, proposes better integrating citizen science into scientific practice,

IIASA is well known for developing innovative research methods to address global problems and citizen science is no exception. A new IIASA-led article just published in Nature Methods Reviews Primers, highlights how citizens can contribute meaningfully to scientific research, thereby becoming an integral part of integrated and evidence-based knowledge creation needed to address some of today’s most pressing challenges, including environmental pollution, food security, biodiversity loss, or the climate crisis. The authors also call attention to the impacts and great potential of citizen science for monitoring progress on ambitious global efforts like the UN Sustainable Development Goals (SDGs), large-scale data collection, and as a viable means to close data gaps and support inclusive decision-making.

Nature Methods Reviews Primers articles are high-quality, introductory review articles describing the current state-of-the-art for applying a specific scientific method. Being invited to write a primer on citizen science is important in two main ways. First, it underlines that the field is earning recognition within the scientific establishment as a valid and valuable approach. Secondly, it offers the opportunity to showcase the breadth and depth of citizen science possibilities to a wide range of scientists and researchers who are not yet familiar with it,” explains co-lead author Gerid Hager, a researcher in the Novel Data Ecosystems for Sustainability Research Group of the IIASA Advancing Systems Analysis Program.

One of the big advantages of citizen science is the fact that it promotes open data practices. In this way, the approach contributes to science innovation by opening science up to society and advancing collaborations between various actors, including citizens, which helps to make science more participatory and inclusive.

“When designed optimally, beyond addressing the data gaps to create effective policies and achieve sustainable development, citizen science can help establish more inclusive data ecosystems that empower individuals and communities, especially those that are hard-to-reach and marginalized,” notes co-lead author Dilek Fraisl, a researcher in the same group at IIASA.

In conclusion, the authors point out that the fields of application for citizen science methods and approaches continue to broaden in terms of subject matter and deepen in terms of the advancement of methodologies as more examples of citizen science research enter the mainstream scientific literature. The principles described in their primer have been successfully applied to a wide range of research domains, particularly in biodiversity research, earth observation and geography, climate change research, or environmental monitoring, which in turn contribute further to the development of both best practice and novel approaches within the ecological and environmental sciences.

Here’s a link to and a citation for the paper,

Citizen science in environmental and ecological sciences by Dilek Fraisl, Gerid Hager, Baptiste Bedessem, Margaret Gold, Pen-Yuan Hsing, Finn Danielsen, Colleen B. Hitchcock, Joseph M. Hulbert, Jaume Piera, Helen Spiers, Martin Thiel & Mordechai Haklay. Nature Reviews Methods Primers volume 2, Article number: 64 (2022) DOI: https://doi.org/10.1038/s43586-022-00144-4 Published: 25 August 2022

This paper appears to be open access.

I don’t usually include the Abstract here but I particularly like the way this one is written,

Citizen science is an increasingly acknowledged approach applied in many scientific domains, and particularly within the environmental and ecological sciences, in which non-professional participants contribute to data collection to advance scientific research. We present contributory citizen science as a valuable method to scientists and practitioners within the environmental and ecological sciences, focusing on the full life cycle of citizen science practice, from design to implementation, evaluation and data management. We highlight key issues in citizen science and how to address them, such as participant engagement and retention, data quality assurance and bias correction, as well as ethical considerations regarding data sharing. We also provide a range of examples to illustrate the diversity of applications, from biodiversity research and land cover assessment to forest health monitoring and marine pollution. The aspects of reproducibility and data sharing are considered, placing citizen science within an encompassing open science perspective. Finally, we discuss its limitations and challenges and present an outlook for the application of citizen science in multiple science domains.

If you are interested in IIASA itself, the website can be found here.

Nanoplastics in the air we breathe

Most of the research I’ve seen about polluting nanoplastics it concerns the ocean; this time it concerns the air. This research dates from November 2021 but I didn’t stumble across it until this February 2, 2022 article by Talib Visram for Fast Company (Note: Links have been removed),

By some estimates, people have discarded 4,900 million tonnes of plastic have into the environment. Once in nature, that plastic starts to degrade, fragmenting into microplastics about the size of a sesame seed, which are inadvertently ingested by humans and animals through eating them in seafood and drinking them in water. Some reports suggest that we all consume five grams a week–about the weight of a bottle cap.

But, we may be taking more plastics into our systems through our respiratory systems. There’s been less investigation of nanoplastics: particles smaller than microplastics, so small that they can move huge distances in the air and be more easily inhaled into the bloodstream. A new study looks at the travel of those lighter particles, finding them abundant in the atmosphere, and carried, via aerosol transmission, even to remote areas. As far as the scientists know, it’s “the most accurate record of air pollution by nanoplastics ever made.”

A February 1, 2022 news item on SciTechDaily.com highlights some of the concerns raised by the research,

In a new study, Empa [Swiss Federal Laboratories for Materials Science and Technology] researcher Dominik Brunner, together with colleagues from Utrecht University and the Austrian Central Institute for Meteorology and Geophysics, is investigating how much plastic is trickling down on us from the atmosphere.

According to the study, some nanoplastics travel over 2000 kilometers through the air. According to the figures from the measurements about 43 trillion miniature plastic particles land in Switzerland every year. Researchers still disagree on the exact number. But according to estimates from the study, it could be as much as 3,000 tonnes of nanoplastics that cover Switzerland every year, from the remote Alps to the urban lowlands. These estimates are very high compared to other studies, and more research is needed to verify these numbers.

….

A January 25, 2022 EMPA [Swiss Federal Laboratories for Materials Science and Technology] press release by Noé Waldmann, which originated the news item, provides some technical details,

In a large-scale fundraising campaign, popular YouTubers like Mister Beast and Mark Rober are currently trying to rid the oceans of almost 14,000 tonnes of plastic waste. That’s about 0.15 per cent of the amount that ends up in the oceans every year. But it’s not just our waters that are full of plastic. A new study shows that the spread of nanoplastic through the air is a more widespread problem than previously thought.

….

Extreme conditions

The scientists studied a small area at an altitude of 3106 meters at the top of the mountain “Hoher Sonnenblick” in the “Hohe Tauern” National Park in Austria. An observatory of the Central Institute for Meteorology and Geodynamics has been located here since 1886. The observatory is run by meteorologist and Arctic researcher Elke Ludewig. Since research began here in the late 19th century, the observatory has only been non-operational on four days. The research station also served as a base for the study on the spread of nanoplastics in remote areas.

Every day, and in all weather conditions, scientists removed a part of the top layer of snow around a marker at 8 AM and carefully stored it. Contamination of the samples by nanoplastics in the air or on the scientists’ clothes was a particular challenge. In the laboratory, the researchers sometimes had to remain motionless when a colleague handled an open sample.

The origin of the tiny particles was traced with the help of European wind and weather data. The researchers could show that the greatest emission of nanoplastics into the atmosphere occurs in densely populated, urban areas. About 30% of the nanoplastic particles measured on the mountain top originate from a radius of 200 kilometers, mainly from cities. However, plastics from the world’s oceans apparently also get into the air via the spray of the waves. Around 10% of the particles measured in the study were blown onto the mountain by wind and weather over 2000 kilometers – some of them from the Atlantic.

Nanoparticles in the bloodstream

It is estimated that more than 8300 million tonnes of plastic have been produced worldwide to date, about 60% of which is now waste. This waste erodes through weathering effects and mechanical abrasion from macro- to micro- and nanoparticles. But discarded plastic is far from the only source. Everyday use of plastic products such as packaging and clothing releases nanoplastics. Particles in this size range are so light that their movement in the air can best be compared to gases.

Besides plastics, there are all kinds of other tiny particles. From Sahara sand to brake pads, the world is buzzing through the air as abrasion. It is as yet unclear whether this kind of air pollution poses a potential health threat to humans. Nanoparticles, unlike microparticles, do not just end up in the stomach. They are sucked deep into the lungs through respiration, where their size may allow them to cross the cell-blood barrier and enter the human bloodstream. Whether this is harmful or even dangerous, however, remains to be researched.

Included here because of its compelling story is Utrecht University’s November 1, 2021 press release conveying the researchers’ excitement, (Note: Links have been removed)

Nanoplastics found in the Alps, transported by air from Frankfurt, Paris and London

A team of researchers have found nanoplastics at the pristine high-altitude Sonnblick Observatory in the Alps. This is the first time that nanoplastics were found in this area. The researchers were originally looking for certain organic particles, but found nanoplastics by chance, discovering a new analysis method for detecting nanoplastics in the process. …

The researchers were looking for organic particles by taking samples of snow or ice, evaporating them, and then burning the residue to detect and analyse the vapours. “Our detection method is a bit like a mechanical nose. And unexpectedly, it smelled burning plastics in our snow samples,” lead researcher Dušan Materić explains. The detector found the smell of several types of plastic, mostly polypropylene (PP) and polyethylene terephthalate (PET).

The detected plastic particles turned out to be less than 200 nm in size, about one hundredth the width of a human hair. That is significantly smaller than plastic particles detected in previous studies. “With this detection method, we are the first group to quantify nanoplastics in the environment,” says Materić. “Since the high Alps are a very remote and pristine area, we were quite shocked and surprised to find such a high concentration of nanoplastics there.” The results suggest that in addition to microplastics, there might be as much nanoplastics present in these remote places.

Transported by air

“We were quite gripped by these findings,” Materić continues. “It’s highly unlikely that these nanoplastics originated from local pristine Alpine areas. So where did they come from? We completely turned around our research project to study this further.”

The researchers found a striking correlation between high concentrations of nanoplastics and winds coming from the direction of major European cities, most notably Frankfurt and the industrial Ruhr area (Germany), but also the Netherlands, Paris, and even London.

“Advanced modelling supported the idea that nanoplastics are indeed transported by air from these urban places,” says Materić. “That’s potentially alarming, because that could mean that there are hotspots of nanoplastics in our cities, and indeed in the very air we’re breathing. We are currently studying this in more detail.” Since working on the current publication, Materić has already received an additional NWO [Dutch Research Council] grant of 50,000 Euros to study the size distribution of nanoplastics in indoor, urban and rural air.

Here’s a link to and a citation for the paper,

Nanoplastics transport to the remote, high-altitude Alps by Dušan Materić,
Elke Ludewig, Dominik Brunner, Thomas Röckmann, Rupert Holzinger. Environmental Pollution Volume 288, 1 November 2021, 117697 DOI: https://doi.org/10.1016/j.envpol.2021.117697

This paper is open access.

A graphene-inorganic-hybrid micro-supercapacitor made of fallen leaves

I wonder if this means the end to leaf blowers. That is almost certainly wishful thinking as the researchers don’t seem to be concerned with how the leaves are gathered.

The schematic illustration of the production of femtosecond laser-induced graphene. Courtesy of KAIST

A January 27, 2022 news item on Nanowerk announces the work (Note: A link has been removed),

A KAIST [Korea Advanced Institute of Science and Technology] research team has developed graphene-inorganic-hybrid micro-supercapacitors made of fallen leaves using femtosecond laser direct laser writing (Advanced Functional Materials, “Green Flexible Graphene-Inorganic-Hybrid Micro-Supercapacitors Made of Fallen Leaves Enabled by Ultrafast Laser Pulses”).

A January 27, 2022 KAIST press release (also on EurekAlert but published January 26, 2022), which originated the news item, delves further into the research,

The rapid development of wearable electronics requires breakthrough innovations in flexible energy storage devices in which micro-supercapacitors have drawn a great deal of interest due to their high power density, long lifetimes, and short charging times. Recently, there has been an enormous increase in waste batteries owing to the growing demand and the shortened replacement cycle in consumer electronics. The safety and environmental issues involved in the collection, recycling, and processing of such waste batteries are creating a number of challenges.

Forests cover about 30 percent of the Earth’s surface and produce a huge amount of fallen leaves. This naturally occurring biomass comes in large quantities and is completely biodegradable, which makes it an attractive sustainable resource. Nevertheless, if the fallen leaves are left neglected instead of being used efficiently, they can contribute to fire hazards, air pollution, and global warming.

To solve both problems at once, a research team led by Professor Young-Jin Kim from the Department of Mechanical Engineering and Dr. Hana Yoon from the Korea Institute of Energy Research developed a novel technology that can create 3D porous graphene microelectrodes with high electrical conductivity by irradiating femtosecond laser pulses on the leaves in ambient air. This one-step fabrication does not require any additional materials or pre-treatment. 

They showed that this technique could quickly and easily produce porous graphene electrodes at a low price, and demonstrated potential applications by fabricating graphene micro-supercapacitors to power an LED and an electronic watch. These results open up a new possibility for the mass production of flexible and green graphene-based electronic devices.

Professor Young-Jin Kim said, “Leaves create forest biomass that comes in unmanageable quantities, so using them for next-generation energy storage devices makes it possible for us to reuse waste resources, thereby establishing a virtuous cycle.” 

This research was published in Advanced Functional Materials last month and was sponsored by the Ministry of Agriculture Food and Rural Affairs, the Korea Forest Service, and the Korea Institute of Energy Research.

Here’s a link to and a citation for the paper,

Green Flexible Graphene–Inorganic-Hybrid Micro-Supercapacitors Made of Fallen Leaves Enabled by Ultrafast Laser Pulses by Truong-Son Dinh Le, Yeong A. Lee, Han Ku Nam, Kyu Yeon Jang, Dongwook Yang, Byunggi Kim, Kanghoon Yim, Seung-Woo Kim, Hana Yoon, Young-Jin Kim. Advanced Functional Materials DOI: https://doi.org/10.1002/adfm.202107768 First published: 05 December 2021

This paper is behind a paywall.

Windows and roofs ‘self-adapt’ to heating and cooling conditions

I have two items about thermochromic coatings. It’s a little confusing since the American Association for the Advancement of Science (AAAS), which publishes the journal featuring both papers has issued a news release that seemingly refers to both papers as a single piece of research.

Onto, the press/new releases from the research institutions to be followed by the AAAS news release.

Nanyang Technological University (NTU) does windows

A December 16, 2021 news item on Nanowerk announced work on energy-saving glass,

An international research team led by scientists from Nanyang Technological University, Singapore (NTU Singapore) has developed a material that, when coated on a glass window panel, can effectively self-adapt to heat or cool rooms across different climate zones in the world, helping to cut energy usage.

Developed by NTU researchers and reported in the journal Science (“Scalable thermochromic smart windows with passive radiative cooling regulation”), the first-of-its-kind glass automatically responds to changing temperatures by switching between heating and cooling.

The self-adaptive glass is developed using layers of vanadium dioxide nanoparticles composite, Poly(methyl methacrylate) (PMMA), and low-emissivity coating to form a unique structure which could modulate heating and cooling simultaneously.

A December 17, 2021 NTU press release (PDF), also on EurekAlert but published December 16, 2021, which originated the news item, delves further into the research (Note: A link has been removed),

The newly developed glass, which has no electrical components, works by exploiting the spectrums of light responsible for heating and cooling.

During summer, the glass suppresses solar heating (near infrared light), while boosting radiative cooling (long-wave infrared) – a natural phenomenon where heat emits through surfaces towards the cold universe – to cool the room. In the winter, it does the opposite to warm up the room.

In lab tests using an infrared camera to visualise results, the glass allowed a controlled amount of heat to emit in various conditions (room temperature – above 70°C), proving its ability to react dynamically to changing weather conditions.

New glass regulates both heating and cooling

Windows are one of the key components in a building’s design, but they are also the least energy-efficient and most complicated part. In the United States alone, window-associated energy consumption (heating and cooling) in buildings accounts for approximately four per cent of their total primary energy usage each year according to an estimation based on data available from the Department of Energy in US.[1]

While scientists elsewhere have developed sustainable innovations to ease this energy demand – such as using low emissivity coatings to prevent heat transfer and electrochromic glass that regulate solar transmission from entering the room by becoming tinted – none of the solutions have been able to modulate both heating and cooling at the same time, until now.

The principal investigator of the study, Dr Long Yi of the NTU School of Materials Science and Engineering (MSE) said, “Most energy-saving windows today tackle the part of solar heat gain caused by visible and near infrared sunlight. However, researchers often overlook the radiative cooling in the long wavelength infrared. While innovations focusing on radiative cooling have been used on walls and roofs, this function becomes undesirable during winter. Our team has demonstrated for the first time a glass that can respond favourably to both wavelengths, meaning that it can continuously self-tune to react to a changing temperature across all seasons.”

As a result of these features, the NTU research team believes their innovation offers a convenient way to conserve energy in buildings since it does not rely on any moving components, electrical mechanisms, or blocking views, to function.

To improve the performance of windows, the simultaneous modulation of both solar transmission and radiative cooling are crucial, said co-authors Professor Gang Tan from The University of Wyoming, USA, and Professor Ronggui Yang from the Huazhong University of Science and Technology, Wuhan, China, who led the building energy saving simulation.

“This innovation fills the missing gap between traditional smart windows and radiative cooling by paving a new research direction to minimise energy consumption,” said Prof Gang Tan.

The study is an example of groundbreaking research that supports the NTU 2025 strategic plan, which seeks to address humanity’s grand challenges on sustainability, and accelerate the translation of research discoveries into innovations that mitigate human impact on the environment.

Innovation useful for a wide range of climate types

As a proof of concept, the scientists tested the energy-saving performance of their invention using simulations of climate data covering all populated parts of the globe (seven climate zones).

The team found the glass they developed showed energy savings in both warm and cool seasons, with an overall energy saving performance of up to 9.5%, or ~330,000 kWh per year (estimated energy required to power 60 household in Singapore for a year) less than commercially available low emissivity glass in a simulated medium sized office building.

First author of the study Wang Shancheng, who is Research Fellow and former PhD student of Dr Long Yi, said, “The results prove the viability of applying our glass in all types of climates as it is able to help cut energy use regardless of hot and cold seasonal temperature fluctuations. This sets our invention apart from current energy-saving windows which tend to find limited use in regions with less seasonal variations.”

Moreover, the heating and cooling performance of their glass can be customised to suit the needs of the market and region for which it is intended.

“We can do so by simply adjusting the structure and composition of special nanocomposite coating layered onto the glass panel, allowing our innovation to be potentially used across a wide range of heat regulating applications, and not limited to windows,” Dr Long Yi said.

Providing an independent view, Professor Liangbing Hu, Herbert Rabin Distinguished Professor, Director of the Center for Materials Innovation at the University of Maryland, USA, said, “Long and co-workers made the original development of smart windows that can regulate the near-infrared sunlight and the long-wave infrared heat. The use of this smart window could be highly important for building energy-saving and decarbonization.”  

A Singapore patent has been filed for the innovation. As the next steps, the research team is aiming to achieve even higher energy-saving performance by working on the design of their nanocomposite coating.

The international research team also includes scientists from Nanjing Tech University, China. The study is supported by the Singapore-HUJ Alliance for Research and Enterprise (SHARE), under the Campus for Research Excellence and Technological Enterprise (CREATE) programme, Minster of Education Research Fund Tier 1, and the Sino-Singapore International Joint Research Institute.

Here’s a link to and a citation for the paper,

Scalable thermochromic smart windows with passive radiative cooling regulation by Shancheng Wang, Tengyao Jiang, Yun Meng, Ronggui Yang, Gang Tan, and Yi Long. Science • 16 Dec 2021 • Vol 374, Issue 6574 • pp. 1501-1504 • DOI: 10.1126/science.abg0291

This paper is behind a paywall.

Lawrence Berkeley National Laboratory (Berkeley Lab; LBNL) does roofs

A December 16, 2021 Lawrence Berkeley National Laboratory news release (also on EurekAlert) announces an energy-saving coating for roofs (Note: Links have been removed),

Scientists have developed an all-season smart-roof coating that keeps homes warm during the winter and cool during the summer without consuming natural gas or electricity. Research findings reported in the journal Science point to a groundbreaking technology that outperforms commercial cool-roof systems in energy savings.

“Our all-season roof coating automatically switches from keeping you cool to warm, depending on outdoor air temperature. This is energy-free, emission-free air conditioning and heating, all in one device,” said Junqiao Wu, a faculty scientist in Berkeley Lab’s Materials Sciences Division and a UC Berkeley professor of materials science and engineering who led the study.

Today’s cool roof systems, such as reflective coatings, membranes, shingles, or tiles, have light-colored or darker “cool-colored” surfaces that cool homes by reflecting sunlight. These systems also emit some of the absorbed solar heat as thermal-infrared radiation; in this natural process known as radiative cooling, thermal-infrared light is radiated away from the surface.

The problem with many cool-roof systems currently on the market is that they continue to radiate heat in the winter, which drives up heating costs, Wu explained.

“Our new material – called a temperature-adaptive radiative coating or TARC – can enable energy savings by automatically turning off the radiative cooling in the winter, overcoming the problem of overcooling,” he said.

A roof for all seasons

Metals are typically good conductors of electricity and heat. In 2017, Wu and his research team discovered that electrons in vanadium dioxide behave like a metal to electricity but an insulator to heat – in other words, they conduct electricity well without conducting much heat. “This behavior contrasts with most other metals where electrons conduct heat and electricity proportionally,” Wu explained.

Vanadium dioxide below about 67 degrees Celsius (153 degrees Fahrenheit) is also transparent to (and hence not absorptive of) thermal-infrared light. But once vanadium dioxide reaches 67 degrees Celsius, it switches to a metal state, becoming absorptive of thermal-infrared light. This ability to switch from one phase to another – in this case, from an insulator to a metal – is characteristic of what’s known as a phase-change material.

To see how vanadium dioxide would perform in a roof system, Wu and his team engineered a 2-centimeter-by-2-centimeter TARC thin-film device.

TARC “looks like Scotch tape, and can be affixed to a solid surface like a rooftop,” Wu said.

In a key experiment, co-lead author Kechao Tang set up a rooftop experiment at Wu’s East Bay home last summer to demonstrate the technology’s viability in a real-world environment.

A wireless measurement device set up on Wu’s balcony continuously recorded responses to changes in direct sunlight and outdoor temperature from a TARC sample, a commercial dark roof sample, and a commercial white roof sample over multiple days.

How TARC outperforms in energy savings

The researchers then used data from the experiment to simulate how TARC would perform year-round in cities representing 15 different climate zones across the continental U.S.

Wu enlisted Ronnen Levinson, a co-author on the study who is a staff scientist and leader of the Heat Island Group in Berkeley Lab’s Energy Technologies Area, to help them refine their model of roof surface temperature. Levinson developed a method to estimate TARC energy savings from a set of more than 100,000 building energy simulations that the Heat Island Group previously performed to evaluate the benefits of cool roofs and cool walls across the United States.

Finnegan Reichertz, a 12th grade student at the East Bay Innovation Academy in Oakland who worked remotely as a summer intern for Wu last year, helped to simulate how TARC and the other roof materials would perform at specific times and on specific days throughout the year for each of the 15 cities or climate zones the researchers studied for the paper.

The researchers found that TARC outperforms existing roof coatings for energy saving in 12 of the 15 climate zones, particularly in regions with wide temperature variations between day and night, such as the San Francisco Bay Area, or between winter and summer, such as New York City.

“With TARC installed, the average household in the U.S. could save up to 10% electricity,” said Tang, who was a postdoctoral researcher in the Wu lab at the time of the study. He is now an assistant professor at Peking University in Beijing, China.

Standard cool roofs have high solar reflectance and high thermal emittance (the ability to release heat by emitting thermal-infrared radiation) even in cool weather.

According to the researchers’ measurements, TARC reflects around 75% of sunlight year-round, but its thermal emittance is high (about 90%) when the ambient temperature is warm (above 25 degrees Celsius or 77 degrees Fahrenheit), promoting heat loss to the sky. In cooler weather, TARC’s thermal emittance automatically switches to low, helping to retain heat from solar absorption and indoor heating, Levinson said.

Findings from infrared spectroscopy experiments using advanced tools at Berkeley Lab’s Molecular Foundry validated the simulations.

“Simple physics predicted TARC would work, but we were surprised it would work so well,” said Wu. “We originally thought the switch from warming to cooling wouldn’t be so dramatic. Our simulations, outdoor experiments, and lab experiments proved otherwise – it’s really exciting.”

The researchers plan to develop TARC prototypes on a larger scale to further test its performance as a practical roof coating. Wu said that TARC may also have potential as a thermally protective coating to prolong battery life in smartphones and laptops, and shield satellites and cars from extremely high or low temperatures. It could also be used to make temperature-regulating fabric for tents, greenhouse coverings, and even hats and jackets.

Co-lead authors on the study were Kaichen Dong and Jiachen Li.

The Molecular Foundry is a nanoscience user facility at Berkeley Lab.

This work was primarily supported by the DOE Office of Science and a Bakar Fellowship.

The technology is available for licensing and collaboration. If interested, please contact Berkeley Lab’s Intellectual Property Office, ipo@lbl.gov.

Here’s a link to and a citation for the paper,

Temperature-adaptive radiative coating for all-season household thermal regulation by Kechao Tang, Kaichen Dong, Jiachen Li, Madeleine P. Gordon, Finnegan G. Reichertz, Hyungjin Kim, Yoonsoo Rho, Qingjun Wang, Chang-Yu Lin, Costas P. Grigoropoulos, Ali Javey, Jeffrey J. Urban, Jie Yao, Ronnen Levinson, Junqiao Wu. Science • 16 Dec 2021 • Vol 374, Issue 6574 • pp. 1504-1509 • DOI: 10.1126/science.abf7136

This paper is behind a paywall.

An interesting news release from the AAAS

While it’s a little confusing as it cites only the ‘window’ research from NTU, the body of this news release offers some additional information about the usefulness of thermochromic materials and seemingly refers to both papers, from a December 16, 2021 AAAS news release,

Temperature-adaptive passive radiative cooling for roofs and windows

When it’s cold out, window glass and roof coatings that use passive radiative cooling to keep buildings cool can be designed to passively turn off radiative cooling to avoid heat loss, two new studies show.  Their proof-of-concept analyses demonstrate that passive radiative cooling can be expanded to warm and cold climate applications and regions, potentially providing all-season energy savings worldwide. Buildings consume roughly 40% of global energy, a large proportion of which is used to keep them cool in warmer climates. However, most temperature regulation systems commonly employed are not very energy efficient and require external power or resources. In contrast, passive radiative cooling technologies, which use outer space as a near-limitless natural heat sink, have been extensively examined as a means of energy-efficient cooling for buildings. This technology uses materials designed to selectively emit narrow-band radiation through the infrared atmospheric window to disperse heat energy into the coldness of space. However, while this approach has proven effective in cooling buildings to below ambient temperatures, it is only helpful during the warmer months or in regions that are perpetually hot. Furthermore, the inability to “turn off” passive cooling in cooler climes or in regions with large seasonal temperature variations means that continuous cooling during colder periods would exacerbate the energy costs of heating. In two different studies, by Shancheng Wang and colleagues and Kechao Tang and colleagues, researchers approach passive radiative cooling from an all-season perspective and present a new, scalable temperature-adaptive radiative technology that passively turns off radiative cooling at lower temperatures. Wang et al. and Tang et al. achieve this using a tungsten-doped vanadium dioxide and show how it can be applied to create both window glass and a flexible roof coating, respectively. Model simulations of the self-adapting materials suggest they could provide year-round energy savings across most climate zones, especially those with substantial seasonal temperature variations. 

I wish them all good luck with getting these materials to market.

Methylene Blue-based sunscreen—anti-aging and coral reef safe

In any event, it’s time to start thinking about sunscreens (for those of us in the Northern Hemisphere.) One other thing, this is informational; it is not an endorsement. A March 1, 2022 Mblue Labs product announcement on EurekAlert (also on EIN Presswire) describes some of the research that went into this new sunscreen,

(Bethesda, MD – March 1, 2022) Mblue Labs releases the first sunscreen based on a recent study that found Methylene Blue, a century old medicine, to be  a highly effective, broad-spectrum UV irradiation protector that absorbs UVA and UVB, repairs ROS (Free Radicals) and UV irradiation induced DNA damages, and is safe for coral reefs. The research paper, “Ultraviolet radiation protection potentials of Methylene Blue for human skin and coral reef health ” was published in Nature’s Scientific Reports (5/28/2021) https://www.nature.com/articles/s41598-021-89970-2 [open access].

80% of today’s sunscreens use Oxybenzone as a chemical UV blocker, despite multiple studies that have shown it expedites the destruction of coral reefs. Several states and countries have now banned the use of Oxybenzone and its derivatives to stop the devastating effects on the world’s marine ecosystem. In addition, consumers focus primarily on the Sun Protection Factor (SPF) to prevent sunburns and potentially dangerous long-term health issues. However, SPF only measures UVB exposure, leaving sunscreen users vulnerable to UVA-triggered oxidative stress and photo-aging.

Our peer-reviewed study demonstrates that Methylene Blue is an effective UV blocker with a number of highly desired characteristics as a novel ingredient to be included in sunscreens. It shows a broad spectrum absorption of both UVA and UVB rays, promotes DNA damage repair, combats reactive oxygen species (ROS) induced by UVA, and most importantly, poses no harm to coral reefs.” says the study’s senior author Dr. Kan Cao, Founder of Mblue Labs, Bluelene Skincare and a Professor at the University of Maryland Department of Cell Biology and Molecular Genetics.

Mblue Labs and the University of Maryland have a pending patent on the property of Methylene Blue as an effective UV blocking agent that also delays skin aging and promotes DNA damage repair. The company’s first anti-aging sunscreen called “Bluevado SunFix”, contains the FDA approved, safe active ingredients Zinc Oxide and Titanium Dioxide, together with an optimized dosage of Methylene Blue. 

“Our Vision for this novel multifunctionsunscreen is deeply rooted in our concern for coral reefs – the rainforest of the ocean. We look forward to working with the industry and the FDA to get Methylene Blue included in the sunscreen monograph. We are confident that Bluevado SunFix not only delivers broad spectrum UVB/UVA protection and post sun repair, but also provides the full anti-aging benefits of our Bluelene Moisturizer with the same cosmetic elegance.”  says Jasmin EL Kordi, CEO Mblue Labs.

This research was supported by a National Science Foundation (NSF) Small Business Technology Transfer Grant (Grant: 1842745). This press release does not necessarily represent the views of the NSF. This study was conducted jointly by researchers at Mblue Labs and the University of Maryland.

About Mblue Labs + Bluelene

MBlue Labs provides revolutionary anti-aging technology to consumers around the world.  The company’s clinical skincare brand Bluelene uses patented ingredient Methylene Blue to repair and protect skin on the mitochondrial level. Mblue Labs’ recent research demonstrates Methylene Blue as the new retinol challenger for anti-aging treatments, in addition to its exciting properties as a new UV sunscreen.

I went looking for the new sunscreen (Bluevado SunFix) and found this,

$58.00

Bluevado SunFix is the first FDA-approved anti-aging sunscreen with Methylene Blue. Methylene Blue’s unique ability to promote skin cell health, repair/delay skin aging and protect against UVA and UVB radiation, is now captured in the bravado of this revolutionary SPF Day Cream.

Our innovative formulation blends Methylene Blue with proven minerals to outperform Oxybenzone, deliver cosmetic elegance, and protect our precious coral reefs from harmful substances. 

Methylene Blue is a preferred alternative to retinol for sensitive skin sufferers and with SunFix there is no retinol sun sensitivity.

Bluevado SunFix is proudly made in the USA and is formulated for ALL skin types.

Preorder now to reserve your SunFix. First shipments are available in mid-March [2022].

Application:

Use as a daily SPF Moisturizer. For sun protection apply 15mins before sun exposure and reapply after 40 minutes of swimming or sweating.

Benefits:

Broad-spectrum UVA/UVB sun protection 

Prevents pre-mature aging 

Repairs photo-aging DNA damage caused by UVA exposure

Reduces fine lines, crows feet, and wrinkles

Improves skin elasticity & firmness

Provides all-day skin hydration

Protects coral reefs

Free USPS shipping for all domestic orders over $34!

Ingredients:

Active Ingredients: Zinc Oxide 8.2%, Titanium Dioxide 2.8%   

Inactive Ingredients: Water (Aqua), Caprylic/Capric Triglyceride, C13-15 Alkane, Cetearyl Alcohol, Glycerin, Oryza Sativa (Rice) Bran Oil, Heptyl Undecylenate, Cetyl Alcohol, Argania Spinosa (Argan) Kernel Oil, Tocopheryl Acetate, Glyceryl Stearate, PEG-100 Stearate, Capryloyl Glycerin/Sebacic Acid Copolymer, Sorbitan Laurate, Butyrospermum Parkii (Shea) Butter, Cocos Nucifera (Coconut) Oil, Bisabolol, Xanthan Gum, Polyhydroxystearic Acid, Jojoba Esters, Polysorbate 60, Ascorbyl Palmitate, Citrus Aurantium Bergamia (Bergamot) Peel Oil, Pelargonium Graveolens (Geranium) Leaf Oil, Citrus Grandis (Grapefruit) Peel Oil, Lavandula Angustifolia (Lavender) Oil, Phenoxyethanol, Caprylyl Glycol, Methylene Blue. [emphasis mine]

Caution: For external use only. Keep out of reach of children. In case of irritation or allergic reaction, discontinue use and consult your physician.

There’s 3 fl oz or 90 mL of product in the tube and it’s SPF 21. (If memory serves, Methylene Blue’s placement at the end of the list ingredients means that it’s the ingredient that weighs the least.)

Again, I am not endorsing this product. That said, it does look interesting.

Caption: Corals exposed to Methylene Blue remain healthy. Credit: Mblue Labs

BTW, Finding a product announcement on EurekAlert (online science news service sponsored by the American Association for the Advancement of Science [AAAS]) was a little unexpected but only because I was ignorant of their Content Eligibility Guidelines (scroll down to Business Announcements). Duly noted.

Sounds of Central African Landscapes; a Cornell (University) Elephant Listening Project

This September 13, 2021 news item about sound recordings taken in a rainforest (on phys.org) is downright fascinating,

More than a million hours of sound recordings are available from the Elephant Listening Project (ELP) in the K. Lisa Yang Center for Conservation Bioacoustics at the Cornell Lab of Ornithology—a rainforest residing in the cloud.

ELP researchers, in collaboration with the Wildlife Conservation Society, use remote recording units to capture the entire soundscape of a Congolese rainforest. Their targets are vocalizations from endangered African forest elephants, but they also capture tropical parrots shrieking, chimps chattering and rainfall spattering on leaves to the beat of grumbling thunder.

For someone who suffers from acrophobia (fear of heights), this is a disturbing picture (how tall is that tree? is the rope reinforced? who or what is holding him up? where is the photographer perched?),

Frelcia Bambi is a member of the Congolese team that deploys sound recorders in the rainforest and analyzes the data. Photo by Sebastien Assoignons, courtesy of the Wildlife Conservation Society.

A September 13, 2021 Cornell University (NY state, US) news release by Pat Leonard, which originated the news item, provides more details about the sounds themselves and the Elephant Listening Project,

“Scientists can use these soundscapes to monitor biodiversity,” said ELP director Peter Wrege. “You could measure overall sound levels before, during and after logging operations, for example. Or hone in on certain frequencies where insects may vocalize. Sound is increasingly being used as a conservation tool, especially for establishing the presence or absence of a species.”

For the past four years, 50 tree-mounted recording units have been collecting data continuously, covering a region that encompasses old logging sites, recent logging sites and part of the Nouabalé-Ndoki National Park in the Republic of the Congo. The sensors sometimes capture the booming guns of poachers, alerting rangers who then head out to track down the illegal activity.

But everyday nature lovers can tune in rainforest sounds, too.

“We’ve had requests to use some of the files for meditation or for yoga,” Wrege said. “It is very soothing to listen to rainforest sounds—you hear the sounds of insects, birds, frogs, chimps, wind and rain all blended together.”

But, as Wrege and others have learned, big data can also be a big problem. The Sounds of Central African Landscapes recordings would gobble up nearly 100 terabytes of computer space, and ELP takes in another eight terabytes every four months. But now, Amazon Web Services is storing the jungle sounds for free under its Open Data Sponsorship Program, which preserves valuable scientific data for public use.

This makes it possible for Wrege to share the jungle sounds and easier for users to analyze them with Amazon tools so they don’t have to move the massive files or try to download them.

Searching for individual species amid the wealth of data is a bit more daunting. ELP uses computer algorithms to search through the recordings for elephant sounds. Wrege has created a detector for the sounds of gorillas beating their chests. There are software platforms that help users create detectors for specific sounds, including Raven Pro 1.6, created by the Cornell Lab’s bioacoustics engineers. Wrege says the next iteration, Raven 2.0, will make this process even easier.

Wrege is also eyeing future educational uses for the recordings which he says could help train in-country biologists to not only collect the data but do the analyses. This is gradually happening now in the Republic of the Congo—ELP’s team of Congolese researchers does all the analysis for gunshot detection, though the elephant analyses are still done at ELP.

“We could use these recordings for internships and student training in Congo and other countries where we work, such as Gabon,” Wrege said. “We can excite young people about conservation in Central Africa. It would be a huge benefit to everyone living there.”

To listen or download clips from Sounds of the Central African Landscape, go to ELP’s data page on Amazon Web Services. You’ll need to create an account with AWS (choose the free option). Then sign in with your username and password. Click on the “recordings” item in the list you see, then “wav/” on the next page. From there you can click on any item in the list to play or download clips that are each 1.3 GB and 24 hours long.

Scientists looking to use sounds for research and analysis should start here.

World Conservation Society Forest Elephant Congo [downloaded from https://congo.wcs.org/Wildlife/Forest-Elephant.aspx]

What follows may be a little cynical but I can’t help noticing that this worthwhile and fascinating project will result in more personal and/or professional data for Amazon since you have to sign up even if all you’re doing is reading or listening to a few files that they’ve made available for the general public. In a sense, Amazon gets ‘paid’ when you give up an email address to them. Plus, Amazon gets to look like a good world citizen.

Let’s hope something greater than one company’s reputation as a world citizen comes out of this.