New glue sticks easily, holds strongly, and is a gas to pull apart

New glue sticks easily, holds strongly, and is a gas to pull apart
A temporary adhesive based on molecular solids is strong enough to hold a chemistry PhD candidate, but can be released without force through the use of heat in a vacuum. Credit: Nicholas Blelloch

Temporary glues may not steal headlines, but they can make everyday life easier.


Sticky office notes, bandage strips and painter’s tape are all examples of products that adhere to surfaces but can be removed with relative ease.

There’s only one drawback. To remove any of those adhesives, the glued surfaces need to be pulled apart from each other.

Dartmouth research has discovered a class of molecular materials that can be used to make temporary adhesives that don’t require force for removal. These non-permanent glues won’t be available as home or office supplies, but they can lead to new manufacturing techniques and pharmaceutical design.

“This temporary adhesive works in an entirely different way than other adhesives,” said Katherine Mirica, an assistant professor of chemistry at Dartmouth. “This innovation will unlock new manufacturing strategies where on-demand release from adhesion is required.”

The Dartmouth research focuses on molecular solids, a special class of adhesive materials that exist as crystals. The molecules in the structures are sublimable, meaning that they shift directly from a solid to a gas without passing through a liquid phase.

The ability to bypass the liquid phase is the key to the new type of temporary adhesives. The adhesive sticks as a solid but then turns to a vapor and releases once it is heated in a vacuum environment.

“The use of sublimation—the direct transition from solid to vapor—is valuable because it offers gentle release from adhesion without the use of solvent or mechanical force,” said Mirica.

Previous Dartmouth research was the first to identify how molecular solids can act as temporary adhesives. According to new research, published in the academic journal Chemistry of Materials, the class of molecules that can be used to make these new-generation materials is wider than previously thought.

“We’ve expanded the list of molecules that can be used as temporary adhesives,” said Nicholas Blelloch, a Ph.D. candidate at Dartmouth and first author of the paper. “Identifying more materials to work with is important because it offers expanded design strategies for bonding surfaces together.”

The research team says the new temporary adhesives can be useful in technical applications such as semiconductor manufacturing and drug development.

When making computer chips, silicon components need to be temporarily bonded. The use of a strong adhesive that releases through sublimation can allow for the development of smaller, more powerful chips since tapes requiring forceful pulling would no longer be required.

In pharmaceuticals, the design principles highlighted through this work can help the development of smaller, faster-acting pills. The adhesives can also be helpful in the design of nano- and micromechanical devices where the use of tape is not possible.

The finding also gives researchers more flexibility in developing temporary adhesives.

“Identifying more molecules with adhesives properties refines our fundamental understating of the multi-scale and multi-faceted factors

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Astronomers discover carbon monoxide gas flowing from distant star system

Nov. 30 (UPI) — Scientists have discovered rapid outflow of carbon dioxide emanating from a star system located 400 light-years away.

Astronomers suggest this unique stage of a planetary system could offer scientists fresh insights into the birth and development of our own solar system.

The discovery is scheduled to be presented next week at the Five Years After HL Tau virtual conference. The research has also been accepted for publication in the journal Monthly Notices of the Royal Astronomical Society.

The outflow of carbon dioxide was first spotted during the survey of young “class III” stars by the Atacama Large Millimetre/submillimetre Array in Chile. Some of these young, low-mass stars host debris rings created by the collision of comets, asteroids and planetesimals.

Because the debris from these collisions absorb and reradiate the energy of their host star, these rings can be detected by ALMA.

Around one star, named “NO Lup,” researchers detected both the glow of a debris and the signature of fast-flowing carbon monoxide.

“Just detecting carbon monoxide gas was exciting, since no other young stars of this type had been previously imaged by ALMA,” astronomer Joshua Lovell, co-author of the soon-to-be-published study, said in a news release.

“But when we looked closer, we found something even more unusual: given how far away the gas was from the star, it was moving much faster than expected. This had us puzzled for quite some time,” said Lovell, a doctoral student at the University of Cambridge.

To solve the mystery, researchers relied on a computer model simulation of NO Lup’s debris ring.

“We found a simple way to explain it: by modeling a gas ring, but giving the gas an extra kick outward,” said Grant Kennedy, who led modeling research for the new study.

“Other models have been used to explain young discs with similar mechanisms, but this disc is more like a debris disc where we haven’t witnessed winds before. Our model showed the gas is entirely consistent with a scenario in which it’s being launched out of the system at around 22 kilometers per second, which is much higher than any stable orbital speed,” said Kennedy, a research fellow at the University of Warwick.

The simulations showed carbon monoxide could be produced by asteroid collisions or by sublimation — the rapid transition from a solid to a gas — on the surface of comets rich with carbon monoxide ice.

Last year, evidence of ancient carbon monoxide ice sublimation was detected on the Kuiper Belt object Ultima Thule by NASA’s New Horizons spacecraft. The latest research suggests this phenomenon may be more common among young stellar systems.

“This fascinating star is shedding light on what kind of physical processes are shaping planetary systems shortly after they are born, just after they have emerged from being enshrouded by their protoplanetary disk,” said study co-author Mark Wyatt.

“While we have seen gas produced by planetesimals in older systems, the shear rate at which gas is being produced in this system and

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Fast-moving gas flowing away from young star caused by icy comet vaporisation

Fast-moving gas flowing away from young star caused by icy comet vaporisation
Artist’s impression of the system, with the star at the center, and the inner dust belt from which gas is produced and dispersed outwards to the far reaches of the system. Credit: Institute of Astronomy, University of Cambridge

A unique stage of planetary system evolution has been imaged by astronomers, showing fast-moving carbon monoxide gas flowing away from a star system over 400 light years away, a discovery that provides an opportunity to study how our own solar system developed.


Astronomers have detected fast-moving carbon monoxide gas flowing away from a young, low-mass star: a unique stage of planetary system evolution which may provide insight into how our own solar system evolved and suggests that the way systems develop may be more complicated than previously thought.

Although it remains unclear how the gas is being ejected so fast, the team of researchers, led by the University of Cambridge, believe it may be produced from icy comets being vaporized in the star’s asteroid belt. The results will be presented at the Five Years After HL Tau virtual conference in December.

The detection was made with the Atacama Large Millimeter/submillimeter Array (ALMA) in Chile, as part of a survey of young ‘class III’ stars, reported in an earlier paper. Some of these class III stars are surrounded by debris disks, which are believed to be formed by the ongoing collisions of comets, asteroids and other solid objects, known as planetesimals, in the outer reaches of recently formed planetary systems. The leftover dust and debris from these collisions absorbs light from their central stars and re-radiate that energy as a faint glow that can be studied with ALMA.

In the inner regions of planetary systems, the processes of planet formation are expected to result in the loss of all the hottest dust, and class IIII stars are those that are left with—at most—dim, cold dust. These faint belts of cold dust are similar to the known debris disks seen around other stars, similar to the Kuiper belt in our own solar system, which is known to host much larger asteroids and comets.

In the survey, the star in question, ‘NO Lup’, which is about 70% the mass of our sun, was found to have a faint, low-mass dusty disk, but it was the only class III star where carbon monoxide gas was detected, a first for this type of young star with ALMA. While it is known that many young stars still host the gas-rich planet-forming disks they are born with, NO Lup is more evolved, and might have been expected to have lost this primordial gas after its planets had formed.

While the detection of carbon monoxide gas is rare, what made the observation unique was the scale and speed of the gas, which prompted a follow-up study to explore its motion and origins.

“Just detecting carbon monoxide gas was exciting, since no other young stars of this type had been previously imaged by ALMA,” said first author Joshua Lovell, a Ph.D.

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3-D printed electrodes free the gas

3-D printed electrodes free the gas
Architected 3-D electrodes: Managing bubble migration in gas evolution reactions at high current densities. Credit: Yat Li.

Alkaline water electrolysis has been touted as a path to establish a hydrogen economy by converting intermittent renewable energies into clean hydrogen-based chemical energy.


However, current technology has achieved only low current densities and voltage efficiencies.

To make electrolysis more resourceful, a Lawrence Livermore National Laboratory (LLNL) team partnered with the University of California, Santa Cruz and two other institutions to develop a 3-D-printed electrode that lessens the problems that occur with gas bubbles that are generated in the process.

One key to making electrolysis achieve higher current density comes down to the gas bubbles created in the process. The bubbles often mingle together, jam and get trapped, making it difficult for them to escape.

“This new electrode gets rid of the gas bubbles faster. You don’t want the bubbles to be trapped in the material; you want to be able to pull them out as quickly as possible and use them as a fuel source,” said LLNL materials scientist Cheng Zhu, the lead LLNL author of a paper appearing in Advanced Energy Materials.

The unique 3-D-printed architecture of the new electrode suppressed gas bubble coalescence, jamming and trapping, and resulted in rapid bubble release. The team found that the current density was 50 times better than the laboratory standard.

The team also used simulations to figure out how the gas forms, how it escapes and the rate at which it escapes. Because you can’t see this process inside of an electrode, the simulations were critical in the design.

“The modeling helped us figure out the fundamental science of the phenomena we saw happening,” said Rongpei Shi, the LLNL materials scientist who conducted the simulations. “The electrodes are not transparent so you can’t look in there and see what’s going on. The controlled platform and modeling are fairly unprecedented to find out about the physics going on inside the electrode.”

The work demonstrates a new approach to the design of 3-D electrodes to enable rapid bubble transport and release to enhance the total electrode catalytic activity at commercially relevant current densities.

“There has been a lot of work done on the material end of electrolysis, looking for electrode catalyst materials. What this team showed is that the actual architecture of the components matter just as much, especially at high production rates,” said Brandon Wood, LLNL’s associate program leader for Hydrogen and Computational Energy Materials in the Materials Science Division and a co-author of the paper.


Flow-through electrodes make hydrogen 50 times faster


More information:
Tianyi Kou et al. Periodic Porous 3D Electrodes Mitigate Gas Bubble Traffic during Alkaline Water Electrolysis at High Current Densities, Advanced Energy Materials (2020). DOI: 10.1002/aenm.202002955
Provided by
Lawrence Livermore National Laboratory

Citation:
3-D printed electrodes free the gas (2020, November 24)
retrieved 24 November 2020
from https://phys.org/news/2020-11-d-electrodes-free-gas.html

This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research,

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South Korean scientists find way to extract carbon emissions from exhaust gas

Nov. 23 (UPI) — South Korean researchers say they have developed technology that can draw out carbon dioxide from industrial emissions and convert the climate-warming gas into calcium carbonate, which then can be adapted for different uses.

Koh Dong-yeun and his team at the Korea Advanced Institute of Science and Technology, KAIST, said they have developed a device to convert carbon dioxide into solid materials, which can be used to make cement and other materials, Aju Daily and Yonhap reported Monday.

The statement from KAIST comes two months after Koh and his team published their findings to the online site of ACS Sustainable Chemistry and Engineering, a peer-reviewed journal.

“The technology helps power plants, steel mills and cement makers, which emit a lot of greenhouse gas, to increase their competitiveness by reducing emission and recycling resources,” Koh said, according to Aju Daily.

The scientists said an ultrapermeable membrane is the foundation of a “hollow fiber module” at the core of the technology, which can be used on factory chimneys.

“We show that a hollow fiber module based on an ultrapermeable membrane synthesized with the polymers of intrinsic microporosity [PIM-1] has the potential to directly utilize [carbon dioxide] from the flue [exhaust] gas stack via a continuous solid carbonation reaction,” the South Korean team said.

Only carbon dioxide can cross the module’s membrane. Once on the other side, carbon dioxide reacts with alkali metal ions to form calcium carbonates, the scientists said, according to Yonhap.

The team at KAIST also said the hollow fiber module is 20 times smaller than conventional devices, according to Aju Daily.

Carbon dioxide in emissions is a major contributor to greenhouse gases. This weekend, the Arctic Circle was an average 12 degrees Fahrenheit above normal, according to the University of Maine’s Climate Reanalyzer, CBS News reported Monday.

Source Article

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Understanding how a catalyst converts methane into ethene could prevent the flaring of natural gas

methane
Photo of landfill burn off flare. Credit: Eddie Hagler/Public Domain

It would be a triple win—for the climate, raw material resources, and the chemical industry. With their work, scientists at the Fritz Haber Institute of the Max Planck Society in Berlin hope to create the basis for extracting useful chemical products such as plastics from the methane that is usually flared off during oil production. They are looking into how to design a catalyst that converts methane into ethene more efficiently than is currently possible. They have now found a ground-breaking clue.


Around 140 billion cubic meters of methane, which escapes during global oil production, are flared every year. This is considerably more than the estimated 90 billion cubic meters of natural gas that Germany consumed in 2019. This not only fuels climate change but also wastes a non-renewable fossil fuel. However, it would not be profitable to build pipelines or liquefaction plants for the relatively small quantities of methane extracted incidentally at individual oil production sites. It would, however, be worthwhile to transport the methane if it could be economically converted into substances that are of interest to the chemical industry. One such substance is ethene, the starting material for polyethylene and many other products. These are produced almost exclusively from crude oil. Unfortunately, the chemical reaction that converts methane directly into ethene proceeds at high temperatures. “This not only costs a lot of energy, but also results in a large proportion of the methane combusting to form the undesirable by-product CO2,” says Annette Trunschke, research group leader at the Fritz Haber Institute of the Max Planck Society. “So it doesn’t quite make sense yet.”

Sodium is the essential component

The chemist and her team want to change this. That’s why they have set their sights on the decisive component of the process: the catalyst made of sodium, manganese, tungsten, and silicon. This facilitates the chemical conversion of methane into ethene—although so far only at 700°C. In order to develop catalysts that work at lower temperatures (i.e. with less energy input) and promote only the formation of the desired products, chemists first need to know what is important in a catalyst for this reaction. According to the research of Trunschke’s group, this essential component is sodium.

“Until now, there have been several theories about which element in the catalyst is crucial for converting methane into ethene,” says Trunschke. “It came as a bit of a surprise that sodium, of all things, was the important component because it should actually evaporate at the high temperatures of the reaction “. However, the research has revealed something else. At high temperatures, the alkali metal is converted into the catalytically active sodium oxide. The oxide is released only for a short time and in minute quantities because of close interaction with the other components of the catalyst, and is thus prevented from evaporating. “This makes it clear that the other components of the catalyst are needed only to release and stabilize

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Global Gas Equipment Industry

Global Gas Equipment Market to Reach $90. 1 Billion by 2027. Amid the COVID-19 crisis, the global market for Gas Equipment estimated at US$61. 4 Billion in the year 2020, is projected to reach a revised size of US$90.

New York, Oct. 23, 2020 (GLOBE NEWSWIRE) — Reportlinker.com announces the release of the report “Global Gas Equipment Industry” – https://www.reportlinker.com/p05798644/?utm_source=GNW
1 Billion by 2027, growing at a CAGR of 5.6% over the analysis period 2020-2027. Atmospheric Gases, one of the segments analyzed in the report, is projected to record a 5.4% CAGR and reach US$31.4 Billion by the end of the analysis period. After an early analysis of the business implications of the pandemic and its induced economic crisis, growth in the Hydrogen segment is readjusted to a revised 6.3% CAGR for the next 7-year period.

The U.S. Market is Estimated at $16.6 Billion, While China is Forecast to Grow at 8.6% CAGR

The Gas Equipment market in the U.S. is estimated at US$16.6 Billion in the year 2020. China, the world`s second largest economy, is forecast to reach a projected market size of US$18.8 Billion by the year 2027 trailing a CAGR of 8.5% over the analysis period 2020 to 2027. Among the other noteworthy geographic markets are Japan and Canada, each forecast to grow at 3.1% and 5.1% respectively over the 2020-2027 period. Within Europe, Germany is forecast to grow at approximately 3.5% CAGR.

Acetylene Segment to Record 5.9% CAGR

In the global Acetylene segment, USA, Canada, Japan, China and Europe will drive the 5.4% CAGR estimated for this segment. These regional markets accounting for a combined market size of US$8.3 Billion in the year 2020 will reach a projected size of US$12 Billion by the close of the analysis period. China will remain among the fastest growing in this cluster of regional markets. Led by countries such as Australia, India, and South Korea, the market in Asia-Pacific is forecast to reach US$12.1 Billion by the year 2027, while Latin America will expand at a 7.1% CAGR through the analysis period. We bring years of research experience to this 9th edition of our report. The 304-page report presents concise insights into how the pandemic has impacted production and the buy side for 2020 and 2021. A short-term phased recovery by key geography is also addressed.

Competitors identified in this market include, among others,

Read the full report: https://www.reportlinker.com/p05798644/?utm_source=GNW

I. INTRODUCTION, METHODOLOGY & REPORT SCOPE

II. EXECUTIVE SUMMARY

1. MARKET OVERVIEW
Global Competitor Market Shares
Gas Equipment Competitor Market Share Scenario Worldwide
(in %): 2019 & 2025
Impact of Covid-19 and a Looming Global Recession

2. FOCUS ON SELECT PLAYERS

3. MARKET TRENDS & DRIVERS

4. GLOBAL MARKET PERSPECTIVE
Table 1: Gas Equipment Global Market Estimates and Forecasts in
US$ Million by Region/Country: 2020-2027

Table 2: Gas Equipment Global Retrospective Market Scenario in
US$ Million by Region/Country: 2012-2019

Table 3: Gas Equipment Market Share Shift across Key
Geographies Worldwide: 2012 VS 2020 VS 2027

Table 4: Atmospheric

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California’s greenhouse gas emissions rose slightly in 2018

California’s greenhouse gas emissions rose slightly in 2018 due largely to lower hydroelectric power use, according to a report released Monday by the state Air Resources Board.



a factory with smoke coming out of it: A refinery in the Wilmington neighborhood of Los Angeles is among the facilities regulated under California's cap-and-trade program to reduce greenhouse gas emissions. (Rick Loomis / Los Angeles Times)


© Provided by The LA Times
A refinery in the Wilmington neighborhood of Los Angeles is among the facilities regulated under California’s cap-and-trade program to reduce greenhouse gas emissions. (Rick Loomis / Los Angeles Times)

The state emitted the equivalent of 425 million metric tons of carbon dioxide in 2018, about 1 million more than in 2017, the Air Resources Board inventory found.

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Pollution overall remained well below the state’s 2020 climate target of 431 million metric tons, which the state hit four years early, in 2016. But the uneven progress underscores the challenge California faces as it pursues the more ambitious goal of slashing planet-warming greenhouse gas emissions another 40% by 2030.

The uptick in 2018 was mostly due to a decrease in the use of hydroelectric power resulting from lower precipitation in the winter of 2017-18, said Dave Clegern, an Air Resources Board spokesman.

“That emissions category rose about 1 million metric tons,” Clegern said. “That was partially compensated by increases in solar generation and other lower greenhouse gas intensity resources.”

Though the year-over-year change is going in the wrong direction, it is “more noise than anything fundamental,” said Danny Cullenward, a lecturer at Stanford Law School. “Nearly all of the state’s climate gains arise in the electricity sector, where a growing share of wind and solar resources reduces emissions over time, and the variability of large hydropower resources causes headline numbers to fluctuate from year to year.”

“California’s clean energy policies are working to clean up the electricity sector,” he added. “But in other sectors — notably transportation, industry and residential and commercial buildings — policy isn’t on track to achieve California’s climate laws.”

Last year’s inventory by the state showed that emissions reductions slowed in 2017, declining by 1.2%, versus a decline of 2.8% in 2016. To be on a pathway to its 2030 goal, California must reverse that trend and significantly pick up the pace of emissions reductions across many sectors.

In one notable improvement, the annual report showed that transportation emissions dropped by 1.5 million metric tons between 2017 and 2018, the first decrease since 2013. Cars, trucks and other vehicles remain California’s largest pollution source, accounting for about 40% of its planet-warming emissions and rising stubbornly for years as driving miles increase.

Cullenward said he is not concerned about the state meeting its 2020 target to reduce its emissions below 1990s levels and that it “will almost certainly be in compliance,” given that global emissions slowed this year amid the COVID-19 pandemic.

“What worries me is that the Air Resources Board does not have a credible plan for how to get the reductions needed to get to California’s 2030 climate target,” he said. “Reducing emissions below that level requires more than progress in the electricity sector, but the major policy the state has identified

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