Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Hot vibrating gases under the electron spotlight

12.12.2017

Tokyo researchers study the dynamics of hot gas molecules by combining electron microscopy and simulation

Gases have been used throughout industry. Natural gas, for example, is "cracked" in refineries to make products like acetylene. The efficiency of gaseous reactions depends on the dynamics of the molecules - their rotation, vibration, and translation (directional movement). These motions provide the kinetic energy to drive reactions. By understanding gas dynamics, we can design more efficient (and environmentally friendly) industrial systems.


Schematic illustration of dynamic behavior of gaseous molecules observed using electron microscopy.

CREDIT: c2017 TERUYASU MIZOGUCHI, INSTITUTE OF INDUSTRIAL SCIENCE, THE UNIVERSITY OF TOKYO

Gas molecules can be studied using transmission electron microscopy (TEM). Unlike optical microscopy, TEM uses a beam of electrons instead of light, and has a much higher resolution, capable of visualizing single atoms. A recent study published in Scientific Reports, reports the work of a team at The University of Tokyo's Institute of Industrial Science (IIS) collaborating with Hitachi High-Technologies Corp.. The researchers used an advanced version of TEM to study the dynamics of simple gases at high temperature.

"In TEM, the energetic electron beam can be used to perform another experiment at the same time, known as energy-loss near-edge structure [ELNES]," study first author Hirotaka Katsukura explains. "The electrons in the beam give up part of their kinetic energy as they pass through the sample. Measuring this energy loss reveals which elements are present and how they are bonded to each other."

In theory, ELNES can also measure the dynamics of gas molecules, not just their chemical bonding. However, researchers had never extracted dynamic information from ELNES before. The IIS team chose four gases - oxygen, methane, nitrogen, and carbon monoxide - whose bonding is well understood, and performed ELNES at room temperature and 1,000°C. Crucially, they also performed computer simulations of these gases, using molecular dynamics code, to theoretically predict the effects of high temperature.

Generally, when molecules are heated up, they vibrate faster and the bonds between their atoms become longer. In the IIS experiments, two gases - oxygen and methane - did indeed show dynamical changes at high temperature, with significantly faster vibration. However, nitrogen and carbon monoxide did not seem to vibrate any differently at 1000°C, despite their extra kinetic energy. Moreover, the simulated high-temperature vibration of methane matched the experiments very closely, but the vibration of hot oxygen was overestimated.

"Gas molecules in a heater can gain kinetic energy in three ways," corresponding author Teruyasu Mizoguchi says. "Namely, by bouncing into each other, by directly touching the heating element, or by indirectly absorbing heat through infrared rays. This last one is only possible for gases with polar chemical bonds, where one element pulls electrons away from the other. That applies to methane (CH4), but not oxygen, a pure element. Therefore, oxygen heated up slower than the simulations predicted."

Meanwhile, the failure of nitrogen and carbon monoxide to undergo vibrational excitation was also a result of their bonds - however, in this case, they were simply too rigid to vibrate much faster. These findings underscore the importance of taking chemical bonding into account, even for apparently simple processes like the vibration of a two-atom molecule.

Nonetheless, the team believes that rapid developments in ELNES will soon make the method sensitive enough to detect vibrational changes even in rigid molecules. This will open the way toward an improved understanding of gas reactions at the atomic level.

The article, "Estimation of the molecular vibration of gases using electron microscopy," was published in Scientific Reports at DOI:10.1038/s41598-017-16423-0.

###

Research contact:

Professor Teruyasu Mizoguchi
Institute of Industrial Science, The University of Tokyo
4-6-1 Komaba, Meguro-ku, Tokyo 153-8505, Japan
Tel: +81-3-5452-6098 ext.57834
Fax:+81-3-5452-6319
Email: teru@iis.u-tokyo.ac.jp

Press officer contact:

Momoyo Matsuyama
Public Relations Office
Institute of Industrial Science, The University of Tokyo
4-6-1 Komaba, Meguro-ku, Tokyo 153-8505, Japan
Tel: +81-3-5452-6738
Fax: +81-3-5452-6746
Email: pro@iis.u-tokyo.ac.jp

About Institute of Industrial Science (IIS), the University of Tokyo:

Institute of Industrial Science (IIS), the University of Tokyo is one of the largest university-attached research institutes in Japan. More than 120 research laboratories, each headed by a faculty member, comprise IIS, with more than 1,000 members including approximately 300 staff and 700 students actively engaged in education and research. Our activities cover almost all the areas of engineering disciplines. Since its foundation in 1949, IIS has worked to bridge the huge gaps that exist between academic disciplines and real-world applications.

Media Contact

Teruyasu Mizoguchi
teru@iis.u-tokyo.ac.jp
81-354-526-098

https://www.iis.u-tokyo.ac.jp/ja/ 

Teruyasu Mizoguchi | EurekAlert!

Further reports about: IIS TEM bonds carbon monoxide chemical bonding electron microscopy gases kinetic energy monoxide nitrogen

More articles from Life Sciences:

nachricht Switch-in-a-cell electrifies life
18.12.2018 | Rice University

nachricht Plant biologists identify mechanism behind transition from insect to wind pollination
18.12.2018 | University of Toronto

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Data storage using individual molecules

Researchers from the University of Basel have reported a new method that allows the physical state of just a few atoms or molecules within a network to be controlled. It is based on the spontaneous self-organization of molecules into extensive networks with pores about one nanometer in size. In the journal ‘small’, the physicists reported on their investigations, which could be of particular importance for the development of new storage devices.

Around the world, researchers are attempting to shrink data storage devices to achieve as large a storage capacity in as small a space as possible. In almost...

Im Focus: Data use draining your battery? Tiny device to speed up memory while also saving power

The more objects we make "smart," from watches to entire buildings, the greater the need for these devices to store and retrieve massive amounts of data quickly without consuming too much power.

Millions of new memory cells could be part of a computer chip and provide that speed and energy savings, thanks to the discovery of a previously unobserved...

Im Focus: An energy-efficient way to stay warm: Sew high-tech heating patches to your clothes

Personal patches could reduce energy waste in buildings, Rutgers-led study says

What if, instead of turning up the thermostat, you could warm up with high-tech, flexible patches sewn into your clothes - while significantly reducing your...

Im Focus: Lethal combination: Drug cocktail turns off the juice to cancer cells

A widely used diabetes medication combined with an antihypertensive drug specifically inhibits tumor growth – this was discovered by researchers from the University of Basel’s Biozentrum two years ago. In a follow-up study, recently published in “Cell Reports”, the scientists report that this drug cocktail induces cancer cell death by switching off their energy supply.

The widely used anti-diabetes drug metformin not only reduces blood sugar but also has an anti-cancer effect. However, the metformin dose commonly used in the...

Im Focus: New Foldable Drone Flies through Narrow Holes in Rescue Missions

A research team from the University of Zurich has developed a new drone that can retract its propeller arms in flight and make itself small to fit through narrow gaps and holes. This is particularly useful when searching for victims of natural disasters.

Inspecting a damaged building after an earthquake or during a fire is exactly the kind of job that human rescuers would like drones to do for them. A flying...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

ICTM Conference 2019: Digitization emerges as an engineering trend for turbomachinery construction

12.12.2018 | Event News

New Plastics Economy Investor Forum - Meeting Point for Innovations

10.12.2018 | Event News

EGU 2019 meeting: Media registration now open

06.12.2018 | Event News

 
Latest News

Pressure tuned magnetism paves the way for novel electronic devices

18.12.2018 | Materials Sciences

New type of low-energy nanolaser that shines in all directions

18.12.2018 | Physics and Astronomy

NASA research reveals Saturn is losing its rings at 'worst-case-scenario' rate

18.12.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>