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Science reveals secrets of a mummy’s portrait

How much information can you get from a speck of purple pigment, no bigger than the diameter of a hair, plucked from an Egyptian portrait that’s nearly 2,000 years old? Plenty, according to a new study. Analysis of that speck can teach us about how the pigment was made, what it’s made of — and maybe even a little about the people who made it. The study is published in the International Journal of Ceramic Engineering and Science.

“We’re very interested in understanding the meaning and origin of the portraits, and finding ways to connect them and come up with a cultural understanding of why they were even painted in the first place,” says materials scientist Darryl Butt, co-author of the study and dean of the College of Mines and Earth Sciences.

Faiyum mummies

The portrait that contained the purple pigment came from an Egyptian mummy, but it doesn’t look the same as what you might initially think of as a mummy — not like the golden sarcophagus of Tutankhamen, nor like the sideways-facing paintings on murals and papyri. Not like Boris Karloff, either.

The portrait, called “Portrait of a Bearded Man,” comes from the second century when Egypt was a Roman province, hence the portraits are more lifelike and less hieroglyphic-like than Egyptian art of previous eras. Most of these portraits come from a region called Faiyum, and around 1,100 are known to exist. They’re painted on wood and were wrapped into the linens that held the mummified body. The portraits were meant to express the likeness of the person, but also their status — either actual or aspirational.

That idea of status is actually very important in this case because the man in the portrait we’re focusing on is wearing purple marks called clavi on his toga. “Since the purple pigment occurred in the clavi — the purple mark on the toga that in Ancient Rome indicated senatorial or equestrian rank- it was thought that perhaps we were seeing an augmentation of the sitter’s importance in the afterlife,” says Glenn Gates of the Walters Art Museum in Baltimore, where the portrait resides.

The color purple, Butt says, is viewed as a symbol of death in some cultures and a symbol of life in others. It was associated with royalty in ancient times, and still is today. Paraphrasing the author Victoria Finlay, Butt says that purple, located at the end of the visible color spectrum, can suggest the end of the known and the beginning of the unknown.

“So the presence of purple on this particular portrait made us wonder what it was made of and what it meant,” Butt says. “The color purple stimulates many questions.”

Lake pigments

Through a microscope, Gates saw that the pigment looked like crushed gems, containing particles ten to a hundred times larger than typical paint particles. To answer the question of how it was made, Gates sent a particle of the pigment to Butt and his team for analysis. The particle was only 50 microns in diameter, about the same as a human hair, which made keeping track of it challenging.

“The particle was shipped to me from Baltimore, sandwiched between two glass slides,” Butt says, “and because it had moved approximately a millimeter during transit, it took us two days to find it.” In order to move the particle to a specimen holder, the team used an eyelash with a tiny quantity of adhesive at its tip to make the transfer. “The process of analyzing something like this is a bit like doing surgery on a flea.”

With that particle, as small as it was, the researchers could machine even smaller samples using a focused ion beam and analyze those samples for their elemental composition.

What did they find? To put the results in context, you’ll need to know how dyes and pigments are made.

Pigments and dyes are not the same things. Dyes are the pure coloring agents, and pigments are the combination of dyes, minerals, binders and other components that make up what we might recognize as paint.

Initially, purple dyes came from a gland of a genus of sea snails called Murex. Butt and his colleagues hypothesize that the purple used in this mummy painting is something else — a synthetic purple.

The researchers also hypothesize that the synthetic purple could have originally been discovered by accident when red dye and blue indigo dye mixed together. The final color may also be due to the introduction of chromium into the mix.

From there, the mineralogy of the pigment sample suggests that the dye was mixed with clay or a silica material to form a pigment. According to Butt, an accomplished painter himself, pigments made in this way are called lake pigments (derived from the same root word as lacquer). Further, the pigment was mixed with a beeswax binder before finally being painted on linden wood.

The pigment showed evidence suggesting a crystal structure in the pigment. “Lake pigments were thought to be without crystallinity prior to this work,” Gates says. “We now know crystalline domains exist in lake pigments, and these can function to ‘trap’ evidence of the environment during pigment creation.”

Bottom of the barrel, er, vat

One other detail added a bit more depth to the story of how this portrait was made. The researchers found significant amounts of lead in the pigment as well and connected that finding with observations from a late 1800s British explorer who reported that the vats of dye in Egyptian dyers’ workshops were made of lead.

“Over time, a story or hypothesis emerged,” Butt says, “suggesting that the Egyptian dyers produced red dye in these lead vats.” And when they were done dyeing at the end of the day, he says, there may have been a sludge that developed inside the vat that was a purplish color. “Or, they were very smart and they may have found a way to take their red dye, shift the color toward purple by adding a salt with transition metals and a mordant [a substance that fixes a dye] to intentionally synthesize a purple pigment. We don’t know.”

Broader impacts

This isn’t Butt’s first time using scientific methods to learn about ancient artwork. He’s been involved with previous similar investigations and has drawn on both his research and artistic backgrounds to develop a class called “The Science of Art” that included studies and discussions on topics that involved dating, understanding and reverse engineering a variety of historical artifacts ranging from pioneer newspapers to ancient art.

“Mixing science and art together is just fun,” he says. “It’s a great way to make learning science more accessible.”

And the work has broader impacts as well. Relatively little is known about the mummy portraits, including whether the same artist painted multiple portraits. Analyzing pigments on an atomic level might provide the chemical fingerprint needed to link portraits to each other.

“Our results suggest one tool for documenting similarities regarding time and place of production of mummy portraits since most were grave-robbed and lack archaeological context,” Gates says.

“So we might be able to connect families,” Butt adds. “We might be able to connect artists to one another.”

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Hackster.io

Nordic nRF9160 DK // Unboxing

We check out this cool kit from Nordic: a multi-sensor cellular IoT prototyping platform for hardware engineers. Easily connect Arduino shields and standalone sensors to the nRF Connect for Cloud platform (nrfcloud.com).

Where the Thingy:91 device (previously: https://www.youtube.com/watch?v=tLUKgDT2V9g) comes with built-in sensors and a consumer-ready interface, the nRF9160 DK empowers you to prototype apps with your own custom hardware.

nRF9160 DK materials:
// https://www.nordicsemi.com/Software-and-tools/Development-Kits/nRF9160-DK
// https://www.nordicsemi.com/Products/Low-power-cellular-IoT/nRF9160

Thingy:91 materials:
// https://www.nordicsemi.com/Software-and-tools/Prototyping-platforms/Nordic-Thingy-91/
// https://www.hackster.io/glowascii/getting-started-with-the-nordic-thingy-91-mac-8d44e5

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ScienceDaily

Biofriendly protocells pump up blood vessels

An international team comprising researchers from the University of Bristol, and Hunan and Central South Universities in China, have prepared biocompatible protocells that generate nitric oxide gas — a known reagent for blood vessel dilation — that when placed inside blood vessels expand the biological tissue.

In a new study published today in Nature Chemistry, Professor Stephen Mann and Dr Mei Li from Bristol’s School of Chemistry, together with Associate Professor Jianbo Liu and colleagues at Hunan University and Central South University in China, prepared synthetic protocells coated in red blood cell fragments for use as nitric oxide generating bio-bots within blood vessels.

Coating the protocells led to increased levels of biocompatibility and longer blood circulation times. Critically, the team trapped an enzyme inside the protocells which, in the presence of glucose, produced hydrogen peroxide. This was then used by haemoglobin in the protocell membrane to degrade the drug molecule hydroxyurea into nitric oxide gas.

When placed inside small pieces of blood vessels, or injected into a carotid artery, the protocells produced sufficient amounts of nitric oxide to initiate the biochemical pathways responsible for blood vessel vasodilation.

Although at a very early stage of development, the new approach could have significant benefits in biomedicine, cellular diagnostics and bioengineering.

Professor Stephen Mann, Co-Director of the Max Planck Bristol Centre for Minimal Biology at Bristol, said: “This work could open up a new horizon in protocell research because it highlights the opportunities for creating therapeutic, cell-like objects that can directly interface with living biological tissues.”

Associate Professor Jianbo Liu at Hunan University added: “We are all really excited about our proof-of-concept studies but there is a lot of work still to be done before protocells can be used effectively as bio-bots in therapeutic applications. But the potential looks enormous.”

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Showing robots how to drive a car…in just a few easy lessons

Imagine if robots could learn from watching demonstrations: you could show a domestic robot how to do routine chores or set a dinner table. In the workplace, you could train robots like new employees, showing them how to perform many duties. On the road, your self-driving car could learn how to drive safely by watching you drive around your neighborhood.

Making progress on that vision, USC researchers have designed a system that lets robots autonomously learn complicated tasks from a very small number of demonstrations — even imperfect ones. The paper, titled Learning from Demonstrations Using Signal Temporal Logic, was presented at the Conference on Robot Learning (CoRL), Nov. 18.

The researchers’ system works by evaluating the quality of each demonstration, so it learns from the mistakes it sees, as well as the successes. While current state-of-art methods need at least 100 demonstrations to nail a specific task, this new method allows robots to learn from only a handful of demonstrations. It also allows robots to learn more intuitively, the way humans learn from each other — you watch someone execute a task, even imperfectly, then try yourself. It doesn’t have to be a “perfect” demonstration for humans to glean knowledge from watching each other.

“Many machine learning and reinforcement learning systems require large amounts of data data and hundreds of demonstrations — you need a human to demonstrate over and over again, which is not feasible,” said lead author Aniruddh Puranic, a Ph.D. student in computer science at the USC Viterbi School of Engineering.

“Also, most people don’t have programming knowledge to explicitly state what the robot needs to do, and a human cannot possibly demonstrate everything that a robot needs to know. What if the robot encounters something it hasn’t seen before? This is a key challenge.”

Learning from demonstrations

Learning from demonstrations is becoming increasingly popular in obtaining effective robot control policies — which control the robot’s movements — for complex tasks. But it is susceptible to imperfections in demonstrations and also raises safety concerns as robots may learn unsafe or undesirable actions.

Also, not all demonstrations are equal: some demonstrations are a better indicator of desired behavior than others and the quality of the demonstrations often depends on the expertise of the user providing the demonstrations.

To address these issues, the researchers integrated “signal temporal logic” or STL to evaluate the quality of demonstrations and automatically rank them to create inherent rewards.

In other words, even if some parts of the demonstrations do not make any sense based on the logic requirements, using this method, the robot can still learn from the imperfect parts. In a way, the system is coming to its own conclusion about the accuracy or success of a demonstration.

“Let’s say robots learn from different types of demonstrations — it could be a hands-on demonstration, videos, or simulations — if I do something that is very unsafe, standard approaches will do one of two things: either, they will completely disregard it, or even worse, the robot will learn the wrong thing,” said co-author Stefanos Nikolaidis, a USC Viterbi assistant professor of computer science.

“In contrast, in a very intelligent way, this work uses some common sense reasoning in the form of logic to understand which parts of the demonstration are good and which parts are not. In essence, this is exactly what also humans do.”

Take, for example, a driving demonstration where someone skips a stop sign. This would be ranked lower by the system than a demonstration of a good driver. But, if during this demonstration, the driver does something intelligent — for instance, applies their brakes to avoid a crash — the robot will still learn from this smart action.

Adapting to human preferences

Signal temporal logic is an expressive mathematical symbolic language that enables robotic reasoning about current and future outcomes. While previous research in this area has used “linear temporal logic,” STL is preferable in this case, said Jyo Deshmukh, a former Toyota engineer and USC Viterbi assistant professor of computer science .

“When we go into the world of cyber physical systems, like robots and self-driving cars, where time is crucial, linear temporal logic becomes a bit cumbersome, because it reasons about sequences of true/false values for variables, while STL allows reasoning about physical signals.”

Puranic, who is advised by Deshmukh, came up with the idea after taking a hands-on robotics class with Nikolaidis, who has been working on developing robots to learn from YouTube videos. The trio decided to test it out. All three said they were surprised by the extent of the system’s success and the professors both credit Puranic for his hard work.

“Compared to a state-of-the-art algorithm, being used extensively in many robotics applications, you see an order of magnitude difference in how many demonstrations are required,” said Nikolaidis.

The system was tested using a Minecraft-style game simulator, but the researchers said the system could also learn from driving simulators and eventually even videos. Next, the researchers hope to try it out on real robots. They said this approach is well suited for applications where maps are known beforehand but there are dynamic obstacles in the map: robots in household environments, warehouses or even space exploration rovers.

“If we want robots to be good teammates and help people, first they need to learn and adapt to human preference very efficiently,” said Nikolaidis. “Our method provides that.”

“I’m excited to integrate this approach into robotic systems to help them efficiently learn from demonstrations, but also effectively help human teammates in a collaborative task.”

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Newborn jets in distant galaxies

Astronomers using data from the ongoing VLA Sky Survey (VLASS) have found a number of distant galaxies with supermassive black holes at their cores that have launched powerful, radio-emitting jets of material within the past two decades or so. The scientists compared data from VLASS with data from an earlier survey that also used the National Science Foundation’s Karl G. Jansky Very Large Array (VLA) to reach their conclusion.

“We found galaxies that showed no evidence of jets before but now show clear indications of having young, compact jets,” said Dr. Kristina Nyland, who is an NRC postdoctoral fellow in residence at the Naval Research Laboratory.

“Jets like these can strongly affect the growth and evolution of their galaxies, but we still don’t understand all of the details. Catching newborn jets with surveys like VLASS provides a measure of the role of powerful radio jets in shaping the lives of the galaxies over billions of years,” Nyland said.

VLASS is a project that will survey the sky visible from the VLA — about 80 percent of the entire sky — three times over seven years. The observations began in 2017 and the first of the three scans now is complete. Nyland and her colleagues compared data from this scan with data from the FIRST survey that used the VLA to observe a smaller portion of the sky between 1993 and 2011.

They found about 2,000 objects that appear in the VLASS images, but were not detected in the earlier FIRST survey. From these, they selected 26 objects that previously were categorized as galaxies with active nuclei — powered by supermassive black holes — by optical and infrared observations. The FIRST observations of the 26 objects had been made between 1994 and 2001. The VLASS observations were made in 2019. The intervals between observations of the objects thus ranged from 18 to 25 years.

They chose 14 of these galaxies for more detailed observations with the VLA. These observations provided higher-resolution images and also were done at multiple radio frequencies to get a more complete understanding of the objects’ characteristics.

“The data from these detailed observations tell us that the most likely cause of the difference in radio brightness between the FIRST and the VLASS observations is that the ‘engines’ at the cores of these galaxies have launched new jets since the FIRST observations were made,” explained Dillon Dong, from Caltech.

The black holes at the cores of galaxies are known to interact with the galaxies themselves, and the two evolve together. The jets launched from the regions near the black holes can affect the amount of star formation within the galaxy.

“Radio jets provide natural laboratories for learning about the extreme physics of supermassive black holes, whose formation and growth are believed to be intrinsically linked to that of the galaxy centers in which they reside,” said Pallavi Patil, of the University of Virginia.

“Jets as young as the ones discovered in our study can provide us with a rare opportunity to gain new insights on how these interactions between the jets and their surroundings work,” Nyland said.

“VLASS has proven to be a key tool for discovering such jets, and we eagerly await the results of its next two observing epochs,” said Mark Lacy, of the National Radio Astronomy Observatory.

Nyland and her colleagues plan further studies of the galaxies using the Very Long Baseline Array (VLBA), the Chandra X-Ray Observatory, and visible-light and infrared telescopes. The paper has been accepted into publication by the Astrophysical Journal.

The National Radio Astronomy Observatory is a facility of the National Science Foundation, operated under cooperative agreement by Associated Universities, Inc.

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In retrospect, the burning of wood in district heating plants has resulted in climate saving

A new report from the University of Copenhagen shows that the burning of wood is significantly more climate friendly than coal and slightly more climate friendly than natural gas over the long run. For the first time, researchers quantified what the conversion of 10 Danish cogeneration plants from coal or natural gas to biomass has meant for their greenhouse gas emissions.

Heat plant

Energy production is responsible for a large part of Danish greenhouse gas emissions. In 2018, more than 20 percent of greenhouse gas emissions were released as a result of heat and electricity production (9.4 out of 48 million tonnes of CO2). Photo: Getty

A conversion to wood biomass (wood chips and pellets) by Danish district heating plants has benefited the climate and is the more climate-friendly option compared to coal and natural gas. These are the findings of a new report from the University of Copenhagen’s Department of Geosciences and Natural Resource Management.

The study is the first retrospective investigation by researchers of what a conversion to wood biomass has meant for greenhouse gas emissions at ten Danish cogeneration plants — and thereby the climate impact of replacing either coal or natural gas in favour of wood biomass.

Among other things, researchers calculated the so-called carbon payback period for each plant, i.e. how long it takes for the conversion to wood biomass to elicit a positive climate effect.

“Our results demonstrate that the transition from coal to wood biomass has had a positive effect on CO2 emissions after an average of six years. When it comes to the transition from natural gas, it has in most cases taken between 9 and 22 years, and in one case 37 years before CO2 emissions were reduced,” says Associate Professor Niclas Scott Bentsen of the Department of Geosciences and Natural Resource Management, who is one of the authors of the report.

Reduction in CO2 emissions

The researchers also looked at the total CO2 emissions from the three energy sources over a 30-year period, which is the life expectancy of a cogeneration plant.

Transitioning from coal to biomass resulted in a 15 to 71 percent reduction in CO2 emissions, while the move away from natural gas resulted in emissions reductions between -4 and 19 percent.

The fact that, in one case, emissions were -4 percent after 30 years as a result of the conversion, is partly due to the fact that, in relation to energy content, burning natural gas emits less CO2 than burning wood, and that this particular plant had notable changes in its product portfolio.

“When such large fluctuations in the figures occur, it is because the payback period and the amount of CO2 emissions saved are significantly affected by the type of fuel, where it comes from and other alternative uses of the wood,” says Associate Professor Niclas Scott Bentsen

Forestry residues are best for the climate

The 10 Danish cogeneration plants collected 32 percent of their wood biomass from Danish forests, while 41 percent was sourced from the Baltic states, seven percent from Russia and Belarus, and seven percent from the United States. The type of wood biomass used and the distance it needed to be transported factored into the carbon budget as well, according to Professor Bentsen.

“For the typical plant that was once coal-fired, but now using wood from around Denmark and only uses forestry residue that cannot be used for other products, the payback period was roughly one year. The 30-year saving was as much as 60%,” explains Niclas Scott Bentsen.

Wood has an enormous potential to displace carbon heavy construction materials such as steel and concrete and is therefore an important aspect of the green transition.

“Our study demonstrates that the extent to which wood is used for construction or other forms of production, where the long lifespan of wood can bind CO2, is even better for the climate than using it as fuel,” says Niclas Scott Bentsen.

FACTS:

The method used in the study includes an analysis of time series from individual plants that includes the pre- and post-conversion period from fossil energy sources to wood biomass. Among other things, the analysis included specific knowledge of the type of fuel used, where the fuel came from and what alternative uses the wood might have had.

Energy production is responsible for a large part of Danish greenhouse gas emissions. In 2018, more than 20 percent of greenhouse gas emissions were released as a result of heat and electricity production (9.4 out of 48 million tonnes of CO2)

Of Denmark’s total energy consumption, 16 percent of energy is generated from the burning of wood biomass. By comparison, 7 percent of energy consumption comes from wind turbines.

To reduce the carbon recovery period and atmospheric CO2 emissions, utilities should focus on using residual biomass (tree branches and crowns from logging or residuals from the wood industry that have no other use), biomass from productive forests, as well as reducing long transport distances.

The project is funded by Danish Energy and the Danish District Heating Association. The project was followed by a follow-up group consisting of representatives from the Council for Green Conversion, the Danish Society for Nature Conservation, Concito and the Danish Energy Agency. The report is peer reviewed by internationally renowned researchers.

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svchamber.org

Shenango Valley Career Opportunities Nov. 10

Check out our weekly #jobsearch chamber newsletter that includes career opportunities from throughout the Shenango Valley region here!

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Chamber Weekly Update Nov. 13, 2020

Check out our weekly newsletter from the chamber here!

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ScienceDaily

Ultra-fast polymer modulators that can take the heat

Datacenters could benefit from lower cooling costs in part to ultra-fast electro-optic modulators developed by researchers in Japan using a polymer that is stable even at temperatures that would boil water.

Reported in the journal Nature Communications, the silicon-polymer hybrid modulators can transmit 200 gigabits of data per second at up to 110 °C and could enable optical data interconnections that are both extremely fast and reliable at high temperatures, reducing the need for cooling and expanding applications in harsh environments like rooftops and cars.

Demand for high-speed data transmission such as for high-definition media streaming has exploded in recent years, and optical communications are central to many of the necessary data connections. A critical component is the modulator, which puts data on a beam of light passing through an electro-optic material that can change its optical properties in response to an electric field.

Most modulators currently use inorganic semiconductors or crystals as the electro-optic material, but organic-based polymers have the advantages that they can be fabricated with excellent electro-optic properties at a low cost and operated at low voltages.

“Polymers have great potential for use in modulators, but reliability issues still need to be overcome for many industry applications,” explains Shiyoshi Yokoyama, professor of Kyushu University’s Institute for Materials Chemistry and Engineering and leader of the research collaboration.

One challenge is that parts of the molecules in the polymer layer must be organized through a process called poling to obtain good electro-optic properties, but this organization can be lost when the layer gets warm enough to begin softening — a point referred to as the glass transition temperature.

However, if the modulators and other components can operate rapidly and reliably even at high temperatures, datacenters could run warmer, thereby reducing their energy usage — nearly 40% of which is currently estimated to go toward cooling.

Employing a polymer they designed to exhibit superb electro-optic properties and a high glass transition temperature of 172 °C through the incorporation of appropriate chemical groups, the research team achieved ultra-fast signaling at elevated temperatures in a silicon-polymer hybrid modulator based on a Mach-Zehnder interferometer configuration, which is less sensitive to temperature changes than some other architectures.

In the modulators, composed of multiple layers including the polymer and silicon, an incoming laser beam is split into two arms of equal length. Applying an electric field across the electro-optic polymer in one of the arms changes the optical properties such that the light wave slightly shifts. When the two arms come back together, interference between the modified and unmodified beams changes the strength of the mixed output beam depending on the amount of phase shift, thereby encoding data in the light.

Using a simple data signaling scheme of just on and off states, rates of over 100 Gbit/s were achieved, while a more complicated method using four signal levels could achieve a rate of 200 Gbit/s.

This performance was maintained with negligible changes even when operating the devices over temperatures ranging from 25 °C to 110 °C and after subjecting the devices to 90 °C heat for 100 hours, demonstrating the robustness and stability of the modulators over an extraordinarily wide range of temperatures.

“Stable operation even when the temperature fluctuates up to 110 °C is wonderful,” says Yokoyama. “This temperature range means operation in controlled environments such as datacenters, even at higher than normal temperatures, and many harsh environments where temperature is not well controlled is possible.”

The current devices are millimeter sized, making them relatively large compared to other designs, but the researchers are looking into ways to further reduce the footprint for incorporation of a dense arrays of such modulators in a small area.

“This kind of performance shows just how promising polymers are for future telecommunications technologies,” Yokoyama states.

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This tableware made from sugarcane and bamboo breaks down in 60 days

Scientists have designed a set of “green” tableware made from sugarcane and bamboo that doesn’t sacrifice on convenience or functionality and could serve as a potential alternative to plastic cups and other disposable plastic containers. Unlike traditional plastic or biodegradable polymers — which can take as long as 450 years or require high temperatures to degrade — this non-toxic, eco-friendly material only takes 60 days to break down and is clean enough to hold your morning coffee ordinner takeout. This plastic alternative is presented November 12 in the journal Matter.

“To be honest, the first time I came to the US in 2007, I was shocked by the available one-time use plastic containers in the supermarket,” says corresponding author Hongli (Julie) Zhu of Northeastern University. “It makes our life easier, but meanwhile, it becomes waste that cannot decompose in the environment.” She later saw many more plastic bowls, plates, and utensils thrown into the trash bin at seminars and parties and thought, “Can we use a more sustainable material?”

To find an alternative for plastic-based food containers, Zhu and her colleagues turned to bamboos and one of the largest food-industry waste products: bagasse, also known as sugarcane pulp. Winding together long and thin bamboo fibers with short and thick bagasse fibers to form a tight network, the team molded containers from the two materials that were mechanically stable and biodegradable. The new green tableware is not only strong enough to hold liquids as plastic does and cleaner than biodegradables made from recycled materials that might not be fully de-inked, but also starts decomposing after being in the soil for 30-45 days and completely loses its shape after 60 days.

“Making food containers is challenging. It needs more than being biodegradable,” said Zhu. “On one side, we need a material that is safe for food; on the other side, the container needs to have good wet mechanical strength and be very clean because the container will be used to take hot coffee, hot lunch.”

The researchers added alkyl ketene dimer (AKD), a widely used eco-friendly chemical in the food industry, to increase oil and water resistance of the molded tableware, ensuring the sturdiness of the product when wet. With the addition of this ingredient, the new tableware outperformed commercial biodegradable food containers, such as other bagasse-based tableware and egg cartons, in mechanical strength, grease resistance, and non-toxicity.

The tableware the researchers developed also comes with another advantage: a significantly smaller carbon footprint. The new product’s manufacturing process emits 97% less CO2 than commercially available plastic containers and 65% less CO2 than paper products and biodegradable plastic. The next step for the team is to make the manufacturing process more energy efficient and bring the cost down even more, to compete with plastic. Although the cost of cups made out of the new material ($2,333/ton) is two times lower than that of biodegradable plastic ($4,750/ton), traditional plastic cups are still slightly cheaper ($2,177/ton).

“It is difficult to forbid people to use one-time use containers because it’s cheap and convenient,” says Zhu. “But I believe one of the good solutions is to use more sustainable materials, to use biodegradable materials to make these one-time use containers.”

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