There’s a good chance you’ve touched something made out of the polyolefin polymer today. It’s often used in polyethylene products like plastic bags or polypropylene products like diapers.
As useful as polyolefins are in society, they continue to multiply as trash in the environment. Scientists estimate plastic bags, for example, will take centuries to degrade.
But now, researchers at Virginia Tech have synthesized a biodegradable alternative to polyolefins using a new catalyst and the polyester polymer, and this breakthrough could eventually have a profound impact on sustainability efforts.
Rong Tong, assistant professor in the Department of Chemical Engineering and affiliated faculty member of Macromolecules Innovation Institute (MII), led the team of researchers, whose findings were recently published in the journal Nature Communications.
One of the largest challenges in polymer chemistry is controlling the tacticity or the stereochemistry of the polymer. When multiplying monomer subunits into the macromolecular chain, it’s difficult for scientists to replicate a consistent arrangement of side-chain functional groups stemming off the main polymer chain. These side-chain functional groups greatly affect a polymer’s physical and chemical properties, such as melting temperature or glass-transition temperature, and regular stereochemistry leads to better properties.
Read more.
By Khai Trung Le
A new type of battery developed by researchers at MIT could be made partly from carbon dioxide captured from power plants. Rather than attempting to convert carbon dioxide to specialized chemicals using metal catalysts, which is currently highly challenging, this battery could continuously convert carbon dioxide into a solid mineral carbonate as it discharges.
The battery is made from lithium metal, carbon, and an electrolyte that the researchers designed. While still based on early-stage research and far from commercial deployment, the new battery formulation could open up new avenues for tailoring electrochemical carbon dioxide conversion reactions, which may ultimately help reduce the emission of the greenhouse gas to the atmosphere.
Currently, power plants equipped with carbon capture systems generally use up to 30 percent of the electricity they generate just to power the capture, release, and storage of carbon dioxide. Anything that can reduce the cost of that capture process, or that can result in an end product that has value, could significantly change the economics of such systems, the researchers say.
Betar Gallant, Assistant Professor of Mechanical Engineering at MIT, said, ‘Carbon dioxide is not very reactive. Trying to find new reaction pathways is important.’Ideally, the gas would undergo reactions that produce something worthwhile, such as a useful chemical or a fuel. However, efforts at electrochemical conversion, usually conducted in water, remain hindered by high energy inputs and poor selectivity of the chemicals produced.
The team looked into whether carbon-dioxide-capture chemistry could be put to use to make carbon-dioxide-loaded electrolytes — one of the three essential parts of a battery — where the captured gas could then be used during the discharge of the battery to provide a power output.
The team developed a new approach that could potentially be used right in the power plant waste stream to make material for one of the main components of a battery. By incorporating the gas in a liquid state, however, Gallant and her co-workers found a way to achieve electrochemical carbon dioxide conversion using only a carbon electrode. The key is to preactivate the carbon dioxide by incorporating it into an amine solution.
‘What we’ve shown for the first time is that this technique activates the carbon dioxide for more facile electrochemistry,’ Gallant says. ‘These two chemistries — aqueous amines and nonaqueous battery electrolytes — are not normally used together, but we found that their combination imparts new and interesting behaviors that can increase the discharge voltage and allow for sustained conversion of carbon dioxide.’
The battery is made from lithium metal, carbon, and an electrolyte that the researchers designed. While still based on early-stage research and far from commercial deployment, the new battery formulation could open up new avenues for tailoring electrochemical carbon dioxide conversion reactions, which may ultimately help reduce the emission of the greenhouse gas to the atmosphere.
“It took many years of vomiting up all the filth I’d been taught about myself, and half-believed, before I was able to walk on the earth as though I had a right to be here.”
— James Baldwin, The Price of the Ticket (via quotespile)
Vandenberg AFB CA (AFP) May 05, 2018 NASA on Saturday blasted off its latest Mars lander, InSight, designed to perch on the surface and listen for “Marsquakes” ahead of eventual human missions to explore the Red Planet. “Three, two, one, liftoff!” said a NASA commentator as the spacecraft launched on a dark, foggy morning atop an Atlas V rocket at 4:05 am Pacific time (1105 GMT) from Vandenberg Air Force Base in California, m Full article
Lego’s new “Women of NASA” set is now available, and the product has already risen to the top of Amazon’s list of best-selling toys.
The set of 231 plastic pieces costs about $25 and went on sale Wednesday morning. Its instant popularity is not surprising to those who have been following Lego’s laudable — and presumably profitable — trend of selling toys that are more inclusive of women.
“Women of NASA” features four mini figurines of pioneering women from the space agency: the astronauts Sally Ride and Mae Jemison, the astronomer Nancy Grace Roman, and the computer scientist Margaret Hamilton.
Continue Reading.
Even without a nervous system, they are able to learn about substances they encounter, retaining that knowledge and even communicating it to other slime moulds.
"Who is afraid of Super Woolf?"
Opens up new possibilities in tissue engineering and soft robotics
Scientists from Nanyang Technological University, Singapore (NTU Singapore) and Carnegie Mellon University (CMU) have found a way to direct the growth of hydrogel, a jelly-like substance, to mimic plant or animal tissue structure and shapes.
The team’s findings, published in Proceedings of the National Academy of Sciences today, suggest new applications in areas such as tissue engineering and soft robotics where hydrogel is commonly used. The team has also filed a patent at CMU and NTU.
In nature, plant or animal tissues are formed as new biomass is added to existing structures. Their shape is the result of different parts of those tissues growing at different rates.
Mimicking this behaviour of biological tissues in nature, the research team comprising CMU scientists Changjin Huang, David Quinn, K. Jimmy Hsia and NTU President-designate Prof Subra Suresh, showed that through manipulation of oxygen concentration, one can pattern and control the growth rate of hydrogels to create the desired complex 3D shapes.
Read more.
A team of researchers at Huazhong University of Science and Technology has developed a silk protein-based gel that they claim allows for skin healing without scarring. In their paper published in the journal Biomaterials Science, the group describes their gel and how well it works.
Scarring due to a skin injury is not just unsightly—for many, it can also be a painful reminder of a wound. For these reasons, scientists have sought a way to heal wounds without scarring. In this new effort, the team in China claims to have found such a solution—a sericin hydrogel.
The gel used by the researchers was based on a silk protein—the researchers extracted sericin from silk fibers and then used a UV light and a photoinitiator to cross-link the protein chains. The result was a gel that adhered well to cells and did not trigger much of an immune response. The researchers note that it also has adjustable mechanical properties. They explain that the gel allows for scar-free healing by inhibiting inflammation and by promoting the development of new blood vessels. It was also found to regulate TGF-β growth factors, which resulted in stem cells being routed to the injury site allowing new skin to develop, rather than scar tissue.
Read more.
Flame Nebula in Orion - For more images of the cosmos Click Here