Category Archives: Chemistry

Signage is seen at the entrance of the United States Court of Appeals for the District of Columbia Circuit in Washington, D.C., U.S., August 30, 2020. REUTERS/Andrew Kelly Acquire Licensing Rights

Dec 1 (Reuters) - A chemical industry trade group on Friday urged a U.S. appeals court to vacate an order from the U.S. Environmental Protection Agency requiring its members to perform new tests to determine whether a petrochemical solvent is toxic to birds, saying the agency failed to explain why the costly analysis was necessary.

Vinyl Institute attorney Eric Gotting told a three-judge panel of the U.S. Court of Appeals for the D.C. Circuit that the EPA had to better explain why existing data was not sufficient before ordering such "time consuming and expensive" tests.

The group has said in court documents that, without a ruling in its favor, the chemical industry could face a "parade of unsubstantiated" testing orders in other reviews in the next several years that could cost tens of millions of dollars.

Circuit Judge Florence Pan, an appointee of Democratic President Joe Biden, asked Gotting what good it would do for the court to tell the EPA to add a more thorough explanation to its testing order since the agency already appeared to have detailed its consideration of testing related to similar chemicals elsewhere in the administrative record.

Isnt that just a formality? Pan asked.

Gotting pushed back, saying the EPA had not supported the need for the testing in the broader record, either.

Amendments to the federal Toxic Substances Control Act (TSCA) passed by Congress in 2016 for the first time gave the EPA authority to require new testing, instead of only relying on existing data to determine toxicity.

Gotting said the 2016 revisions require the EPA to thoroughly explain why it needs new testing, but the agency did not do so.

I dont think the information is there yet, Gotting said. He added: Even in the administrative record, they still have to point this court to something where they did some analysis.

U.S. Department of Justice attorney Laura Brown said Friday the law was changed to strengthen and streamline reviews and argued the Vinyl Institute is seeking to impose unnecessary and burdensome procedures on the EPA that would undermine the intent of the revisions.

Were at the point where, is EPAs burden to explain everything they did in a test order and the purpose of the test order? The reason Congress has given EPA this new authority is to make the process simpler for EPA to get the information, Brown said.

But Circuit Judge Justin Walker, an appointee of Republican former President Donald Trump, said he is not sure the EPA can just ask that their word be taken at face value that testing is needed when issuing orders, even if the agency doesnt need to list every piece of evidence it has already looked at.

I think thats a broad spectrum and I think probably the standard is in between there, he said.

The EPA had told Formosa Plastics Corp, Westlake Chemical Corp, Occidental Chemical Corp and other Vinyl Institute members in 2022 that it had some data indicating that 1,1,2-trichloroethane, which is used in plastics and petrochemical manufacturing, may be toxic to birds, but said it needed further testing to confirm.

EPA reporting data indicates more than 100 million pounds of the chemical were produced or imported into the U.S. in most years between 1986 and 2015.

The panel also included Circuit Judge Karen Henderson, an appointee of former Republican President George H.W. Bush, who largely remained quiet during the arguments.

The case is Vinyl Institute Inc. V. EPA, U.S. Court of Appeals for the D.C. Circuit, case No. 22-1089.

For the Vinyl Institute: Eric Gotting, Peter de la Cruz and Gregory Clark of Keller and Heckman

For the EPA: Laura Brown of the U.S. Department of Justice

Reporting by Clark Mindock

Our Standards: The Thomson Reuters Trust Principles.

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Chemical industry urges U.S. appeals court to curtail EPA testing ... - Reuters

Courtesy of Amazon MGM Studios

Despite a late-November release, Emerald Fennells Saltburn has quickly become one of the years most talked-about movies, already generating Oscar buzz. Ahead of the films screening at Austin Film Festival last month, The Daily Texan sat down with the Academy Award-winning writer-director to talk about her new film.

The Daily Texan: What was the most important lesson you brought from your first film, Promising Young Woman, when making Saltburn?

Emerald Fennell: With Promising, it was (made in) a short amount of time and I had a specific idea in my head that wasnt obvious to other people initially. We had an amazing time, but there wasnt time to have the moments of collaboration, which means you end up with really special, interesting and complicated things. We were running against the clock. This time, having more time in prep so I could dig into the production design even more than I had in Promising Young Woman let people be their best.

DT: Did having that extra time benefit your writing or directing process more?

EF: The writing process is always the same. Ive been visiting Saltburn in my head for eight years it was one of the imaginary worlds I visited a lot. I live in the world and go there as Oliver, and then bit by bit, the story and the characters coalesce and then after years and years, certain scenes are done. And then things change and once it stops changing, once the story is finished, I write it down. In terms of directing, I didnt want to make something with an insane budget (or) an insane amount of time because that makes it a bit slack. Youve got to be up against the clock and up against the budget, making everything work and having to be imaginative all the time.

DT: What was your intention with the mirror symbolism that permeates the film?

EF: So much of it was me and (cinematographer) Linus (Sandgren) talking about doubling and not only the idea of the doppelganger, but our identities and how unbelievably fractured and elusive they are. It made sense that you would always be seeing somebody looking at themselves but not quite themselves or seeing versions of them duplicated. But also, theres something about this genre and the nature of those houses which lends itself to voyeurism. The idea of these houses is that there are eyes everywhere but you never see them and there are hands that you never see clearing everything away because the staff only appear once the family leave. Theres a sexy voyeurism built into the architecture of the houses. And of course the thing about the mirror thats so important is that you can break it but it just gets fixed you can never really break it.

DT: What made Barry Keoghan and Jacob Elordi the right pair to put at the center of this film?

EF: So much of its about chemistry. Barrys got this extraordinary, fascinating, enigmatic charisma. Jacob is similarly charismatic but (hes) much more open. Theyre a brilliant pair because theyre both doing something very different but equally powerful. I hadnt seen Jacob in Euphoria when I met him, but I like to speak to people before I talk about a project. Im interested in how honest people are. Thats not to say were not all lying to each other and ourselves all the time, its more like, are we going to be able to have a real conversation? And its difficult because its personal and complicated. There are lots of people who do want to get into that kind of stuff. But for me, to make something complicated, honest, difficult, sticky and sexy in a disturbing way, youve got to be comfortable talking about things.

DT: What advice do you have for student filmmakers?

EF: If theres something you dont understand, or you feel like theres an itch you cant quite scratch, the best thing to do is to write it or make it because the likelihood is other people feel the same way, and theyll want to talk about it too and connect with it. Its going for the thing that feels complicated and interesting, whatever that is.

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Emerald Fennell talks mirrors, chemistry in 'Saltburn' The Daily ... - The Daily Texan

Following an offseason highlighted by player movement, the Wolves have decided to stand behind the often-criticized duo of Karl-Anthony Towns and Rudy Gobert. This comes despite a significant amount of noise from fans and media alike, who believed the pairing would fail to develop chemistry.

Now, the Minnesota Timberwolves have opened the 2023-24 NBA season with a 12-4 record, the best 16-game start to a campaign in franchise history, surely proving many doubters wrong.

For most of the prior season, the Gobert trade was widely regarded as a failed experiment; however, the truth is that the team didn't have a significant sample size with the two big men playing together. Towns only played 29 total regular season games last year due to a calf injury, with 27 of those games being played with the Frenchman.

The NBA is a league now dominated by player movement, and with anything that alters the fabric of a top sports league, there will be positives and negatives. The reason I bring that up is because I believe this has drastically changed fan and media expectations. In this era of the league, it seems there is little patience. If players are underperforming in a fresh situation, there is no grace period to become adjusted to new coaching philosophies, new teammates and even a whole new city.

Now, in their second year together, the twin towers seem to be finally meshing in Minnesota. Towns are actively trying to involve Gobert on offense, and the two seem to be truly understanding the spacing they need to maintain when on the court together.

Of course, the two bigs play a huge part in the Timberwolves success so far, but Anthony Edwards has taken a huge leap and can now be labeled, in my opinion, as a budding superstar.

Ant has increased his scoring from 24.6 to 26.6 ppg, but more importantly, he has shown tremendous growth and maturity as a facilitator. Averaging a career-high 5.3 apg, Edwards growth is displayed even more from the eye test rather than looking at the numbers. The young All-Star has emphasized making the extra pass this season, a mentality that has seemingly trickled down the roster.

With players like Gobert, versatile wing Nickeil Alexander-Walker, and veteran Mike Conley becoming more comfortable embracing their roles, the Wolves have been able to shift into another gear.

When watching, you can see a sense of urgency and togetherness throughout the team, a dynamic that has been missing for quite some time. The players clearly enjoy sharing the court and are playing for more than just a paycheque.

Equipped with a deep bench, a young superstar, and a versatile big-man tandem, the Timberwolves championship window is now, and who knows how long itll be open.

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The importance of the Timberwolves' chemistry - Dunking with Wolves

Astrophysicists using NASAs James Webb Space Telescope have discovered that teenage galaxies, emerging within the first 2-3 billion years after the Big Bang, exhibit high temperatures and unexpected elements like nickel. This research, part of the CECILIA Survey, provides new insights into the early stages of galactic development.

Similar to human teenagers, teenage galaxies are awkward, experience growth spurts and enjoy heavy metal nickel, that is.

A Northwestern University-led team of astrophysicists has just analyzed the first results from the CECILIA (Chemical Evolution Constrained using Ionized Lines in Interstellar Aurorae) Survey, a program that uses NASAs James Webb Space Telescope (JWST) to study the chemistry of distant galaxies.

According to the early results, so-called teenage galaxies which formed two-to-three billion years after the Big Bang are unusually hot and contain unexpected elements, like nickel, which are notoriously difficult to observe.

The research was published on November 20 in The Astrophysical Journal Letters. It marks the first in a series of forthcoming studies from the CECILIA Survey.

Were trying to understand how galaxies grew and changed over the 14 billion years of cosmic history, said Northwesterns Allison Strom, who led the study. Using the JWST, our program targets teenage galaxies when they were going through a messy time of growth spurts and change. Teenagers often have experiences that determine their trajectories into adulthood. For galaxies, its the same.

Light from 23 distant galaxies, identified with red rectangles in the Hubble Space Telescope image at the top, were combined to capture incredibly faint emission from eight different elements, which are labelled in the JWST spectrum at the bottom.Although scientists regularly find these elements on Earth, astronomers rarely, if ever, observe many of them in distant galaxies. Credit: Aaron M. Geller, Northwestern, CIERA + IT-RCDS

One of the principal investigators of the CECILIA Survey, Strom is an assistant professor of physics and astronomy at Northwesterns Weinberg College of Arts and Sciences and a member of Northwesterns Center for Interdisciplinary Exploration and Research in Astrophysics (CIERA). Strom co-leads the CECILIA Survey with Gwen Rudie, a staff scientist at Carnegie Observatories.

Named after Cecilia Payne-Gaposchkin, one of the first women to earn a Ph.D. in astronomy, the CECILIA Survey observes spectra (or the amount of light across different wavelengths) from distant galaxies. Strom likens a galaxys spectra to its chemical DNA. By examining this DNA during a galaxys teenage years, researchers can better understand how it grew and how it will evolve into a more mature galaxy.

For example, astrophysicists still dont understand why some galaxies appear red and dead while others, like our Milky Way, are still forming stars. A galaxys spectrum can reveal its key elements, such as oxygen and sulfur, which provide a window into what a galaxy was previously doing and what it might do in the future.

These teenage years are really important because thats when the most growth happens, Strom said. By studying this, we can begin exploring the physics that caused the Milky Way to look like the Milky Way and why it might look different from its neighboring galaxies.

In the new study, Strom and her collaborators used the JWST to observe 33 distant teenage galaxies for a continuous 30 hours this past summer. Then, they combined spectra from 23 of those galaxies to construct a composite picture.

This washes out the details of individual galaxies but gives us a better sense of an average galaxy. It also allows us to see fainter features, Strom said. Its significantly deeper and more detailed than any spectrum we could collect with ground-based telescopes of galaxies from this time period in the universes history.

The ultra-deep spectrum revealed eight distinct elements: Hydrogen, helium, nitrogen, oxygen, silicon, sulfur, argon, and nickel. All elements that are heavier than hydrogen and helium form inside stars. So, the presence of certain elements provides information about star formation throughout a galaxys evolution.

While Strom expected to see lighter elements, she was particularly surprised by the presence of nickel. Heavier than iron, nickel is rare and incredibly difficult to observe.

Never in my wildest dreams did I imagine we would see nickel, Strom said. Even in nearby galaxies, people dont observe this. There has to be enough of an element present in a galaxy and the right conditions to observe it. No one ever talks about observing nickel. Elements have to be glowing in gas in order for us to see them. So, in order for us to see nickel, there may be something unique about the stars within the galaxies.

Another surprise: The teenage galaxies were extremely hot. By examining the spectra, physicists can calculate a galaxys temperature. While the hottest pockets with galaxies can reach over 9,700 degrees Celsius (17,492 degrees Fahrenheit), the teenage galaxies clock in at higher than 13,350 degrees Celsius (24,062 degrees Fahrenheit).

This is justadditional evidence of how different galaxies likely were when they were younger, Strom said. Ultimately, the fact that we see a higher characteristic temperature is just another manifestation of their different chemical DNA because the temperature and chemistry of gas in galaxies are intrinsically linked.

Reference: CECILIA: The Faint Emission Line Spectrum of z 23 Star-forming Galaxies by Allison L. Strom, Gwen C. Rudie, Ryan F. Trainor, Gabriel B. Brammer, Michael V. Maseda, Menelaos Raptis, Noah S. J. Rogers, Charles C. Steidel, Yuguang Chen, and David R. Law, 20 November 2023, The Astrophysical Journal Letters. DOI: 10.3847/2041-8213/ad07dc

The study was supported by NASA, the Pittsburgh Foundation, and the Research Corporation for Scientific Advancement. The data were obtained from the Mikulski Archive for Space Telescopes at the Space Telescope Science Institute and from the W.M. Keck Observatory.

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Strange Chemistry: Webb Reveals Teenage Galaxies Are ... - SciTechDaily

Since chlorohydrazones are planar molecules, it is in principle possible to distinguish between their E and Z stereoisomers. Chlorohydrazones are known to preferentially assume the Z configuration around the C=N double bond, and their (E, Z) isomerization is almost suppressed [...] Read more.Since chlorohydrazones are planar molecules, it is in principle possible to distinguish between their E and Z stereoisomers. Chlorohydrazones are known to preferentially assume the Z configuration around the C=N double bond, and their (E, Z) isomerization is almost suppressed at room temperature. The lack, or rather the difficulty, of such an isomerization has been conveniently addressed by the in-depth theoretical study of seven C-methoxycarbonyl-N-aryl chlorohydrazones (aryl = phenyl, 4-chlorophenyl, 4-bromophenyl, 4-iodophenyl, 2-chlorophenyl, 2-bromophenyl, and 2-iodophenyl). DFT B97M-D4/cc-pVTZ calculations of these C-methoxycarbonyl-N-aryl chlorohydrazones, supported by the XRD determination of the molecular structure, provided a complete picture of the isomerization processes in the studied compounds. The analysis of the energetics, molecular geometry, and electronic structure (the latter in the framework of the Quantum Theory of Atoms In Molecules) showed that the Z isomers are thermodynamically favored because, within the low-energy planar isomers with extensive conjugation, the electrostatic interactions between the dipoles of the CO, CCl, and NH bonds overcome the stabilization induced by the NH O bond present in the E isomers. We confirmed that the (E, Z) isomerization occurs by the umklapp mechanism, in which the NHAr moiety rotates in the molecular plane towards a linear C=NN configuration and then proceeds to the other isomer. The (E, Z) isomerization is very slow at room temperature because the umklapp interconversion has high barriers (110 kJ/mol) despite the extended electron delocalization present in the transition state.Full article

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Banner image:Chemistry chair Wei Zhang (right) and Graduate Research Assistant Zepeng Lei study plastic materials in the Zhang Lab. (Credit:Patrick Campbell/CU Boulder)

One day in the not-too-distant future, the plastics in our satellites, cars and electronics may all be living their second, 25th or 250th lives.

New research from CU Boulder, published in Nature Chemistry, details how a class of durable plastics widely used in the aerospace and microelectronics industries can be chemically broken down into their most basic building blocks and then formed once again into the same material.

Its a major step in the development of repairable and fully recyclable network polymers, a particularly challenging material to recycle, as it is designed to hold its shape and integrity in extreme heat and other harsh conditions. The study documents how this type of plastic can be perpetually broken down and remade, without sacrificing its desired physical properties.

We are thinking outside the box, about different ways of breaking chemical bonds, said Wei Zhang, lead author of the study and chair of the chemistry department. Our chemical methods can help create new technologies and new materials, as well as be utilized to help solve the existing plastic materials crisis.

A detail of recycled plastic.Photo by Patrick Campbell/CU Boulder.

The PCN film directly peeled off from the glass substrate shows high transparency and flexibility. Photo by Zepeng Lei.

Their results also suggest that revisiting the chemical structures of other plastic materials could lead to similar discoveries of how to fully break down and rebuild their chemical bonds, enabling the circular production of more plastic materials in our daily lives.

In the mid-20th century, plastics were ubiquitously adopted in almost every industry and part of life as they are extremely convenient, functional and cheap. But half a century later, after exponential demand and production, plastics pose a major problem to the health of the planet and to people. The production of plastics requires large amounts of oil and the burning of fossil fuels. Disposable plastics create hundreds of millions of tons of waste every year, which ends up in landfills, oceans and even in our bodies, in the form of microplastics.

Recycling, therefore, is key to reducing plastic pollution and fossil fuel emissions this century.

Conventional recycling methods mechanically break down polymers into powders, burn them or use bacterial enzymes to dissolve them. The goal is to end up with smaller pieces that can be used for something else. Think shoes made from recycled rubber tires or clothing made from recycled plastic water bottles. Its not the same material anymore, but it doesnt end up in a landfill or the ocean.

But what if you could rebuild a new item from the same material? What if recycling didnt just offer a second life to plastics, but a repeat experience?

Thats exactly what Zhang and his colleagues have accomplished: They reversed a chemical method and discovered they can both break and form new chemical bonds in a particularly high-performance polymer.

This chemistry can also be dynamic, can be reversible, and that bond can be reformed, said Zhang. We are thinking about a different way to form the same backbone, just from different starting points.

They do this by breaking the polymerpoly meaning manyback into singular monomers, its molecules, a concept of reversible or dynamic chemistry. Whats especially novel about this latest method is that it has not only created a new class of polymer material that, like Legos, are easy to build, break apart and rebuild over and over, but the method can be applied to existing, especially hard-to-recycle polymers.

These new chemical methods are also ready for commercialization and can plug and play with current industrial production.

It can really benefit future design and development of plastics to not only create new polymers, but its also very important to know how to convert, upcycle and recycle older polymers, said Zhang. By using our new approach, we can prepare many new materialssome of which could have similar properties to the plastics in our daily life.

This advance in the closed-loop recycling of plastics is inspired by the natural world, as plants, animals and human beings alike are currently part of a planetary-level, circular system of recycling, said Zhang.

Why cant we make our materials the same way?

Additional authors on this publication include: Zepeng Lei, Hongxuan Chen, Yicheng Rong and Yiming Hu, Department of Chemistry, University of Colorado Boulder; Chaoqian Luo and Kai Yu, Department of Mechanical Engineering, University of Colorado Denver; Yinghua Jin, RockyTech, Ltd. Boulder, Colorado; and Rong Long, Department of Mechanical Engineering, University of Colorado Boulder.

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Plastics of the future will live many past lives, thanks to chemical recycling - University of Colorado Boulder