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Computing With Honey | Earth Wise           

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Researchers are always working to develop faster and more powerful computers.  Some of them believe that the future of computing lies with neuromorphic computers, which are systems designed to mimic the neurons and synapses found in the human brain.

The human brain has more than 100 billion neurons with more than 1 quadrillion synapses or connections among them.  These numbers far exceed anything people have built.  There have been some neuromorphic computer chips made that have the equivalent of more than 100 million neurons per chip, but this is still far less than the number in the brain.  Despite all its complexity, the brain uses vastly less power than a powerful computer.  Some supercomputers use tens of millions of watts to operate; the brain uses around 10 to 20 watts.

Many researchers are searching for biodegradable and renewable ways to make neuromorphic computing components.  Researchers at Washington State University have demonstrated a way to make them using, of all things, honey.  The honey is used to form a memristor, which is a component similar to a transistor that can both process and store data in memory.  The device uses honey processed into a solid form and sandwiched between two metal electrodes.  The organic device is very stable and reliable over a long time.

So far, these devices are on a micro scale – about the size of a human hair.  The researchers want to develop them on a nanoscale, which is about 1/1000 the width of a human hair, and then bundle many millions or even billions together to make a neuromorphic computing system.  Such a honey-based system would be renewable and biodegradable – which, pardon the pun, would be really sweet.

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Honey holds potential for making brain-like computer chips

Photo, posted January 28, 2008, courtesy of Dino Giordano via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Better Ways To Make Bioplastics | Earth Wise

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The world produces over 300 million tons of plastics each year, mostly produced from petroleum.  The environmental consequences are substantial and there is a critical need to replace as much of that plastic production with biodegradable plastics as possible.  Thus, there is global research aimed at making bioplastics more economical and as environmentally friendly as possible.

Researchers at Texas A&M University have developed an improved approach for making bioplastics from corn stubble, grasses, and mesquite agricultural production.  Apart from the obvious environmental benefits of having biodegradable plastics, producing bioplastics from common agricultural waste would create new revenue streams for farmers as well as the people who transport harvested feedstock and byproduct crops to refinery operations.

The key to bioplastic production is the efficient extraction and use of lignin, the organic polymer that is the primary structural support material in most plants.  The new research takes five conventional pretreatment technologies for plant materials and modifies them to produce both biofuel and plastics together at a lower cost.  The new method is called “plug-in preconditioning processes of lignin” and it can be directly and economically added into current biorefineries.  The process is designed to integrate dissolving, conditioning, and fermenting lignin, extracting energy from it and making it easily adaptable to biorefinery designs.

The so-called bioeconomy currently supports some 286,000 jobs.  Innovation is the key to achieving more widespread use of biodegradable plastic.  With improved economics of so-called lignocellulosic biorefineries, there can be new avenues to use agricultural waste to produce biodegradable plastics.

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‘Plugging in’ to produce environmentally friendly bioplastics

Photo, posted November 5, 2015, courtesy of Kathryn Faith via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Seeds And Climate Change | Earth Wise

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Farmers and agricultural communities around the world are on the frontlines of climate change.  They are among the first to feel the impacts of hotter temperatures as well as more frequent and intense droughts and precipitation. These challenges pose a massive threat to both farmer livelihoods and global food security.

As the planet continues to heat up, many arid regions that already have marginal conditions for agriculture will be increasingly under stress. As a result, researchers from the Massachusetts Institute of Technology and the King Mohammed VI Polytechnic University in Morocco are working on a promising new way to protect seeds from this stress during their crucial germination phase. Their simple and inexpensive process, which was recently described in a paper published in the journal Nature Food, also provides plants with extra nutrition at the same.

The research team has developed a two layer coating for seeds designed for tackling issues related to drought. Drawing inspiration from natural coatings that occur on some seeds like chia seeds, the first layer is designed to protect the seeds from drying out. It provides a gel-like coating that grips any moisture that comes along and surrounds the seed with it.  The second (inner) layer of the coating contains preserved microorganisms called rhizobacteria, as well as some nutrients to help the seeds grow. 

The materials for the coatings are biodegradable, readily-available, and often used in the food industry already.  According to researchers, early tests using common beans have demonstrated encouraging results in Morocco, and more field tests of the seeds are currently underway.

As the climate continues to change, more innovations like this will be necessary for global food security.

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Engineering seeds to resist drought

Photo, posted September 17, 2010, courtesy of Stacy via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Takeout Food And Ocean Litter | Earth Wise

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The Covid-19 pandemic saw most of us making use of take-out or delivery services as our only access to restaurant food.  It was a valuable link to normal life.  But unfortunately, the packaging of takeout food is a major contributor to the global plastic waste problem that isn’t going to disappear just because people are returning to eating in restaurants.

A new analysis of more than 12 million items by UK researchers published in the journal Nature Sustainability has found that the majority of ocean litter collected around the world is in the form of takeout food items:  bags, wrappers, containers, straws and cutlery, aluminum cans, and plastic and glass bottles.  Eighty percent of all the items surveyed were made of plastic.

Wrappers and packaging tended to concentrate along coasts, gathering on the shore and the sea floor.  Takeout trash was rarer in the open ocean.  In those areas, fishing debris accounted for half of the litter.

The authors of the study argue that efforts to curb plastic waste should prioritize takeout food and beverage containers.  They recommend that avoidable takeout items, like single-use plastic bags, should be replaced with non-plastic and biodegradable materials.  The authors also recommended making plastic producers responsible for the collection and disposal of plastic products.

As of July 1, the European Union has banned the 10 most common plastic and Stryofoam products found on European beaches.  The EU is also establishing an active European market for recycled plastics based on the principles of extended producer responsibility.

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Takeout Food and Drink Containers Account for Bulk of Ocean Litter

Photo, posted September 14, 2009, courtesy of Susan White/USFWS via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Turning Wood Into Plastic | Earth Wise

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Plastic pollution is particularly pernicious because plastics can take hundreds of years to degrade in the environment.  For this reason, researchers across the globe search for ways to shift from petrochemical plastics to ones that are biodegradable.

Producing biodegradable plastics is challenging both from the standpoint of the methods needed and from the results obtained.  Producing them often requires toxic chemicals and can be very expensive.  The materials that emerge often do not have the durability and strength of conventional plastics and can be unstable when exposed to moisture.

Researchers at the Yale School of the Environment have developed a process of decomposing the porous matrix of natural wood into a slurry that can be formed into a biodegradable plastic.  The material shows high mechanical strength, stability when holding liquids, and is resistant to the effects of ultraviolet light.  Along with all these favorable properties, the material can be recycled or safely biodegraded in the natural environment.

The slurry mixture is created by taking wood powder – a processing residue usually discarded in lumber mills – and deconstructing it with a biodegradable and recyclable solvent.  The resulting mixture has a high solid content and high viscosity and can be casted and rolled without breaking.

The researchers conducted a comprehensive life cycle assessment to test the environmental impacts of the bioplastic compared with conventional plastics.  Sheets of it were buried in soil and observed to fracture after two weeks and completely degrade after three months.  The material can also be broken back down into the slurry by mechanical stirring.

The remaining topic to investigate is the potential impact on forests if the manufacturing of this bioplastic is scaled up.

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Turning wood into plastic

Photo, posted October 12, 2016, courtesy of the US Forest Service via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Food Waste Into Wearables | Earth Wise

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A new startup company spun out of the University of Toronto wants to make clothing from food waste.  If they are successful, you may someday buy a shirt or a pair of gym shorts made from banana peels, rotten tomatoes, coffee grounds, or moldy bread.

A problem faced by the clothing industry is that most textiles are blended with synthetic and non-renewable fiber polyester, which makes them unrecyclable.  An alternative that has come on the scene in recent years is polylactic acid (or PLA), which is a decomposable bioplastic that is currently used for food packaging, medical implants, and 3D printing.  It is likely that a sustainable future for the fashion industry will depend on the ability to make use of biodegradable and carbon-neutral materials.

PLA is typically made from cornstalk, but the startup – called ALT TEX – does not want to rely on a crop already used for feedstock, human consumption, and alternative fuel.  Furthermore, there is no need to plant more corn when there is an abundant supply of unused post-industrial food waste from growers, producers, and retailers that contains the same biological building blocks for producing PLA.

ALT TEX has been conducting experiments using discarded apples to create a PLA-based fabric that is strong, durable, decomposable, and cost effective.  They are working with farmers and food suppliers to access their waste. If their efforts are successful, it would be possible to divert significant amounts of organic waste that currently emits the powerful greenhouse gas methane and instead enable the fashion industry to be more sustainable.

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Earth-friendly fashion: U of T startup turns food waste into wearables

Photo, posted August 30, 2019, courtesy of Ruth Hartnup via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Plants Paying For Biofuels | Earth Wise

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Biofuels are an important element in broader strategies to replace petroleum in transportation fuels like gasoline, diesel, and jet fuel.  The idea is that biofuels recycle carbon by getting it from growing plants rather than from fossil sources.  The biggest problem with biofuels is that they cost more than conventional petroleum fuels, so there is economic incentive to keep burning the fossil fuels.

One strategy to make biofuels cost competitive is to have the plants provide additional economic benefits beyond being a feedstock for fuel.  This in principle can be done by engineering plants to produce valuable chemical compounds, or bioproducts, as they grow.  Bioproducts include such things as flavoring agents and fragrances as well as biodegradable plastic.  These bioproducts can be extracted from the plants and then the remaining plant material can be converted to fuel. 

Researchers at Lawrence Berkeley National Laboratory recently published a study to determine what quantities of bioproducts plants need to produce to result in cost-effective biofuel production.

The study looked at a compound called limonene, which is used for flavoring and fragrance.  They calculated that if this compound was accumulated at 0.6% of the biomass dry weight, it would offer net economic benefits to biorefineries.  This corresponds to recovering 130 pounds of limonene from 10 tons of sorghum on an acre of land.

Such quantities are completely practical but, on the other hand, none of these substances are needed in huge quantities. Just six refineries could supply the world with limonene.  So, fuel crops would need to be engineered to produce a broad range of bioproducts to enable a viable cost-effective biofuel industry.

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Making Biofuels Cheaper by Putting Plants to Work

Photo, posted September 28, 2019, courtesy of Michele Dorsey Walfred via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Sustainable Plastics

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According to the United Nations, plastic accounts for up to 90% of all the pollutants in the ocean. Conventional plastics take hundreds of years to decay, so all the plastic that gets into the oceans piles up and endangers marine life and pollutes the environment. Unfortunately, there are few comparable, environmentally friendly alternatives.  

An often-proposed solution is bioplastics, which are not made from petroleum and degrade quickly.  The downside of bioplastics is that growing the plants or bacteria used to make the plastic requires fertile soil and fresh water, which are scarce commodities in many places.

One such place is Israel.  So, researchers there at Tel Aviv University have developed a process to make a bioplastic polymer that doesn’t require land or fresh water.  The new polymer is derived from microorganisms that feed on seaweed.  It is biodegradable, produces zero toxic waste and recycles into organic waste.

The polymer is called polyhydroxyalkanoate, or PHA for short.  The raw material is multicellular seaweed, cultivated in the ocean.  These algae are eaten by single-celled microorganisms, which also grow in salty seawater and produce a polymer that can be used to make bioplastic.  PHA is already produced in commercial quantities, but it is currently made from plants that require agricultural land and fresh water.  The new process would enable countries with limited fresh water, such as Israel, China and India, to switch from petroleum-based plastics to biodegradable plastics.

Plastics from fossil sources are one of the world’s biggest pollution problems.  The new study shows that it is possible to produce bioplastic completely based on marine resources in an environmentally-friendly process. 

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Sustainable ‘plastics’ are on the horizon

Photo, posted March 14, 2015, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Car Parts From Agricultural Waste

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A new bio-composite material made from date palm fiber biomass could be used to produce sustainable, lightweight and low-cost parts for the automobile and marine industries.

A team of researchers from the UK has developed a date palm fiber polycaprolactone composite that is completely biodegradable, renewable,sustainable and recyclable, in contrast to synthetic composite materials reinforced by glass and carbon fibers. The team tested the mechanical properties of the material and found that it achieved better low-velocity impact resistance than traditional man-made composites.

The idea would be to use the material in non-structural auto parts such as car bumpers and door linings.   The result would be to reduce the weight of vehicles, contributing to less fuel consumption and lower emissions.  The new material can be produced using less energy than glass and carbon fibers and is biodegradable and therefore easier to recycle.

Date palm fibers are one of the most available natural fibers in many parts of the world.  The trees produce a large quantity of agricultural waste, which is mostly burned or land-filled,causing serious environmental problems.

Convincing industry to use a new class of materials such as natural-fiber reinforced composites is challenging.  First it is necessary to obtain consistent,reliable properties from the material. Then the industries need to work closely with the developers to test the materials and convince themselves of the viability of using them.  The team, led by researchers at the University of Portsmouth, has been working with industry to test the viability of parts made from a variety of other sustainable materials as well including flax, hemp, and jute.  Someday, our cars may have bumpers made from agricultural waste.

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Agricultural waste drives us closer to greener transport

Photo, posted October 27, 2017, courtesy of David Stanley via Flickr. 

Earth Wise is a production of WAMC Northeast Public Radio.

Mass Production Of Biodegradable Plastic  

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Plastic pollution is a major problem for the world’s oceans and non-biodegradable plastics continue to fill the planet’s landfills and litter the landscape.   There are many approaches to making plant-derived, biodegradable plastics but most of these materials do not offer the resistance to heat and moisture that is characteristic of petroleum-based plastics.

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Biodegradable Microbeads

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Microbeads are little spheres of plastic less than half a millimeter in diameter that are added to a variety of personal care and cleaning products such as cosmetics, sunscreens and fillers.  They give these products a desirable smooth texture.   However, they are so small that sewage filtration systems can’t remove them and they end up in rivers and oceans where they are ingested by birds, fish and other marine life.

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Edible Tableware

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The problems caused by plastics in the environment continue to mount.  Major companies around the world are endorsing and promoting efforts to combat the problem including the New Plastics Economy Initiative which aims to have 70% of plastic packaging reused and recycled globally, which is five times more than the current percentage.

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Packaging From The Sea

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Waste due to excess packaging of the products we buy is a real problem.  It is one that most of us are conscious of and more and more businesses are making efforts toward eco-friendly packaging.  There is increased use of cardboard, which is recyclable.  Most of us try to reduce our waste through recycling.  But as we buy more things online and have a growing variety of things delivered to our homes, it is a struggle to receive the things we order in good condition and not end up with piles of packaging materials.

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K-Cups And The Environment

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k-cups

The biggest news in the past decade in the coffee business is not the arrival of yet another new Starbucks two blocks from the old one.  It is the explosive growth of pod-based coffee machines.  These gadgets used to just be in offices and businesses, but almost one in three American homes now has one.

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