Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Air bubbles in breakfast syrup illustrate potential pathway to new technology

03.11.2004


The behavior of air bubbles in ordinary breakfast syrup demonstrates how scientists might be able to make vanishingly thin tubes and fibers for biomedical and other applications.



Previous experiments conducted in Sidney Nagel’s laboratory at the University of Chicago showed how to make liquid threads that measure only 10 microns in diameter (approximately one-fifth the diameter of a human hair). Now his Chicago colleague Wendy Zhang reports in the current issue of Physical Review Letters that it is theoretically possible to make much thinner threads by slightly altering experimental procedures. If proven in the laboratory, the technique has potential use in fiber optics, electronics and other industries. "There are many people who are trying to use this idea, or ideas like this, to make very thin wires," said Zhang, an Assistant Professor in Physics at the University of Chicago. "They’re very interested to know what’s the smallest size that they can achieve."

The calculation that Zhang devised to answer that question indicates there is no theoretical limit to the thinness of a thread produced via fluid flow. But the calculation doesn’t account for the microscopic building blocks of matter. In reality, she said, a thread cannot be thinner than the molecules of which it is made. "In my opinion, this great work will open wide new avenues for the controlled production of extremely thin and long holes in materials like polymers, glasses and ceramics," said Alfonso Gañán-Calvo of the Universidad de Sevilla in Spain. He added that the work could have "an enormous impact in fields from biomedicine and biotechnology to the hot nanotech industry."


This line of research began for Zhang in the laboratory of Nagel, the Stein-Freiler Distinguished Service Professor in Physics. Nagel has made what he calls "physics at the breakfast table" one of the hallmarks of his research. When Nagel introduced Zhang to his experiments in the flow of viscous fluids several years ago, "I was completely enchanted," she said.

Despite the whimsical breakfast theme, serious issues lurk behind Nagel’s work. He, along with Milan Mrksich, Professor in Chemistry, and Mark Garfinkel, Assistant Professor in Surgery, both at the University of Chicago, are working on a precisely controlled method of fluid flow to protect transplanted insulin-producing cells from the body’s immune system. The team has successfully coated small clumps of cells, but Zhang wondered if it would be possible to coat individual cells, should the need arise.

An ordinary bottle of syrup demonstrates the principle of viscous entrainment, the topic of Zhang’s paper. If you turn a bottle upside-down, a large air bubble slowly rises to the top. "With a long enough bottle, the rising movement can distort the bubble so severely that it takes on a tear-drop shape, with a thin tendril of air being drawn out from the rear," she explained.

The phenomenon illustrates how the flow in syrup naturally creates small, extended structures-in this case the trailing tendril of air, Zhang said. To make this tendril smaller than the 10-micron limit that Nagel and his associates have observed in the laboratory, they would need to constantly adjust the pressure on the back of the tube to keep the shape of the interface between the fluid and the air at the front always the same. "It’s an odd way to do the experiment. It’s not something that a good experimentalist would do just for the heck of it because it’s inconvenient and there’s no obvious payback," Zhang said. "But if the idea is right, there is a payback."

A method that already exists, called electrospinning, can make microscopically thin fibers. But Zhang noted that viscous entrainment has advantages over electrospinning. For example, electrospinning was recently adapted to create hollow fibers. This requires the use of two liquids, one for the sheath and one for the core, then remove the core. "There is a possibility that viscous entrainment would work directly with air so that you can do the entire processing in one step," Zhang said.

Today her idea exists only as a calculation in a scientific journal. It remains to be seen whether it will work in practice. "You don’t know until someone’s actually used it," she said.

Steve Koppes | EurekAlert!
Further information:
http://www.uchicago.edu

More articles from Agricultural and Forestry Science:

nachricht New insight into why Pierce's disease is so deadly to grapevines
11.06.2018 | University of California - Davis

nachricht Where are Europe’s last primary forests?
29.05.2018 | Humboldt-Universität zu Berlin

All articles from Agricultural and Forestry Science >>>

The most recent press releases about innovation >>>

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

Im Focus: Temperature-controlled fiber-optic light source with liquid core

In a recent publication in the renowned journal Optica, scientists of Leibniz-Institute of Photonic Technology (Leibniz IPHT) in Jena showed that they can accurately control the optical properties of liquid-core fiber lasers and therefore their spectral band width by temperature and pressure tuning.

Already last year, the researchers provided experimental proof of a new dynamic of hybrid solitons– temporally and spectrally stationary light waves resulting...

Im Focus: Overdosing on Calcium

Nano crystals impact stem cell fate during bone formation

Scientists from the University of Freiburg and the University of Basel identified a master regulator for bone regeneration. Prasad Shastri, Professor of...

Im Focus: AchemAsia 2019 will take place in Shanghai

Moving into its fourth decade, AchemAsia is setting out for new horizons: The International Expo and Innovation Forum for Sustainable Chemical Production will take place from 21-23 May 2019 in Shanghai, China. With an updated event profile, the eleventh edition focusses on topics that are especially relevant for the Chinese process industry, putting a strong emphasis on sustainability and innovation.

Founded in 1989 as a spin-off of ACHEMA to cater to the needs of China’s then developing industry, AchemAsia has since grown into a platform where the latest...

Im Focus: First real-time test of Li-Fi utilization for the industrial Internet of Things

The BMBF-funded OWICELLS project was successfully completed with a final presentation at the BMW plant in Munich. The presentation demonstrated a Li-Fi communication with a mobile robot, while the robot carried out usual production processes (welding, moving and testing parts) in a 5x5m² production cell. The robust, optical wireless transmission is based on spatial diversity; in other words, data is sent and received simultaneously by several LEDs and several photodiodes. The system can transmit data at more than 100 Mbit/s and five milliseconds latency.

Modern production technologies in the automobile industry must become more flexible in order to fulfil individual customer requirements.

Im Focus: Sharp images with flexible fibers

An international team of scientists has discovered a new way to transfer image information through multimodal fibers with almost no distortion - even if the fiber is bent. The results of the study, to which scientist from the Leibniz-Institute of Photonic Technology Jena (Leibniz IPHT) contributed, were published on 6thJune in the highly-cited journal Physical Review Letters.

Endoscopes allow doctors to see into a patient’s body like through a keyhole. Typically, the images are transmitted via a bundle of several hundreds of optical...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Munich conference on asteroid detection, tracking and defense

13.06.2018 | Event News

2nd International Baltic Earth Conference in Denmark: “The Baltic Sea region in Transition”

08.06.2018 | Event News

ISEKI_Food 2018: Conference with Holistic View of Food Production

05.06.2018 | Event News

 
Latest News

Graphene assembled film shows higher thermal conductivity than graphite film

22.06.2018 | Materials Sciences

Fast rising bedrock below West Antarctica reveals an extremely fluid Earth mantle

22.06.2018 | Earth Sciences

Zebrafish's near 360 degree UV-vision knocks stripes off Google Street View

22.06.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>