Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

First uses of new solar energy technology: Killing germs on medical, dental instruments

09.09.2013
A revolutionary new solar energy technology that turns water into steam without boiling the entire container of water has become the basis for new devices to sanitize medical and dental instruments and human waste in developing countries, scientists said here today.

Prototypes of the devices, which need no electricity or fuel, were the topic of one of the keynote addresses at the opening of the 246th National Meeting & Exposition of the American Chemical Society (ACS), the world's largest scientific society. The meeting, which features almost 7,000 reports on new advances in science and other topics, continues through Thursday in the Indiana Convention Center and downtown hotels.

Naomi Halas, D.Sc., pointed out that almost 2 billion people live in areas of the world without a regular supply of electricity. That electricity is key to using machines called autoclaves, which produce scorching-hot steam to sterilize medical and dental instruments. Without that basic machine, doctors must rely on chemicals, which can be costly and difficult to transport, to prevent the spread of germs and disease from medical and dental instruments.

"We have developed a solution, our solar steam technology," Halas said. She is with Rice University. "It is completely off-grid, uses sunlight as the energy source, is not that large, kills disease-causing microbes effectively and relatively quickly and is easy to operate. This is an incredibly promising technology."

Halas and colleagues have prototypes of two solar steam machines. One is the autoclave for sterilizing medical and dental instruments. The second is an autoclave for disinfecting human and animal wastes, which are another major source of disease transmission in developing countries and other resource-limited areas. The technology could be expanded to provide steam for direct use in purifying dirty or salty water for drinking and cooking — with the solar-generated steam simply allowed to condense into pure distilled water. Possibilities also exist for adapting the technology to produce steam to spin small electric turbines to generate electricity.

Their tests showed that the prototype autoclaves produced steam at temperatures ranging from 239 to 270 degrees Fahrenheit. Steam production adequate for sterilization began within about 5 minutes. It continued for periods of time long enough to sterilize liquid and solid materials placed inside the device, consistent with U.S. Food and Drug Administration sterilization guidelines. The heat and pressure produced by the steam was great enough to kill the most heat-resistant living microbes, and also viruses and the tough spores that microbes form to survive hostile environmental conditions.

The autoclaves are the first practical applications of a new solar energy technology described earlier in 2012 in ACS Nano, one of the ACS' more than 40 peer-reviewed scientific journals. Metallic nanoparticles — bits of material so small that hundreds would fit inside the period at the end of this sentence — go into a container of water. Sunlight focused into the water quickly heats the nanoparticles, which scientists are terming "nanoheaters." A layer of steam forms on the nanoheaters and buoys them up to the water's surface. They release the steam and sink back down into the water to repeat the process.

"Nanoheaters generate steam at a remarkably high efficiency," Halas said. "More than 80 percent of the energy they absorb from sunlight goes into production of steam. In the conventional production of steam, you would have to heat the entire container of water until it boils, with the bubbles rising to the top to release steam. With nanoheaters, less than 20 percent of the energy heats the neighboring liquid."

The prototype autoclaves consist of a dish-like mirror that focuses sunlight into a container of water with the nanoheaters.

A video on the solar heater technology is available here.

Halas recently formed a company that is working on moving the devices from the prototype stage to commercial products. She and her collaborators are seeking ways to make them more rugged and at a more reasonable cost. They are also exploring even more applications for the technology.

A press conference on this topic will be held Sunday, Sept. 8, at 1 p.m. in the ACS Press Center, Room 211, in the Indiana Convention Center. Reporters can attend in person or access live audio and video of the event and ask questions at http://www.ustream.tv/channel/acslive.

Halas acknowledged funding from the Bill and Melinda Gates Foundation.

The American Chemical Society is a nonprofit organization chartered by the U.S. Congress. With more than 163,000 members, ACS is the world's largest scientific society and a global leader in providing access to chemistry-related research through its multiple databases, peer-reviewed journals and scientific conferences. Its main offices are in Washington, D.C., and Columbus, Ohio.

To automatically receive news releases from the American Chemical Society, contact newsroom@acs.org.

Note to journalists: Please report that this research was presented at a meeting of the American Chemical Society.

Michael Bernstein | EurekAlert!
Further information:
http://www.acs.org

More articles from Life Sciences:

nachricht Nanoparticle Exposure Can Awaken Dormant Viruses in the Lungs
16.01.2017 | Helmholtz Zentrum München - Deutsches Forschungszentrum für Gesundheit und Umwelt

nachricht Cholera bacteria infect more effectively with a simple twist of shape
13.01.2017 | Princeton University

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Designing Architecture with Solar Building Envelopes

Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.

As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...

Im Focus: How to inflate a hardened concrete shell with a weight of 80 t

At TU Wien, an alternative for resource intensive formwork for the construction of concrete domes was developed. It is now used in a test dome for the Austrian Federal Railways Infrastructure (ÖBB Infrastruktur).

Concrete shells are efficient structures, but not very resource efficient. The formwork for the construction of concrete domes alone requires a high amount of...

Im Focus: Bacterial Pac Man molecule snaps at sugar

Many pathogens use certain sugar compounds from their host to help conceal themselves against the immune system. Scientists at the University of Bonn have now, in cooperation with researchers at the University of York in the United Kingdom, analyzed the dynamics of a bacterial molecule that is involved in this process. They demonstrate that the protein grabs onto the sugar molecule with a Pac Man-like chewing motion and holds it until it can be used. Their results could help design therapeutics that could make the protein poorer at grabbing and holding and hence compromise the pathogen in the host. The study has now been published in “Biophysical Journal”.

The cells of the mouth, nose and intestinal mucosa produce large quantities of a chemical called sialic acid. Many bacteria possess a special transport system...

Im Focus: Newly proposed reference datasets improve weather satellite data quality

UMD, NOAA collaboration demonstrates suitability of in-orbit datasets for weather satellite calibration

"Traffic and weather, together on the hour!" blasts your local radio station, while your smartphone knows the weather halfway across the world. A network of...

Im Focus: Repairing defects in fiber-reinforced plastics more efficiently

Fiber-reinforced plastics (FRP) are frequently used in the aeronautic and automobile industry. However, the repair of workpieces made of these composite materials is often less profitable than exchanging the part. In order to increase the lifetime of FRP parts and to make them more eco-efficient, the Laser Zentrum Hannover e.V. (LZH) and the Apodius GmbH want to combine a new measuring device for fiber layer orientation with an innovative laser-based repair process.

Defects in FRP pieces may be production or operation-related. Whether or not repair is cost-effective depends on the geometry of the defective area, the tools...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

12V, 48V, high-voltage – trends in E/E automotive architecture

10.01.2017 | Event News

2nd Conference on Non-Textual Information on 10 and 11 May 2017 in Hannover

09.01.2017 | Event News

Nothing will happen without batteries making it happen!

05.01.2017 | Event News

 
Latest News

Multiregional brain on a chip

16.01.2017 | Power and Electrical Engineering

New technology enables 5-D imaging in live animals, humans

16.01.2017 | Information Technology

Researchers develop environmentally friendly soy air filter

16.01.2017 | Power and Electrical Engineering

VideoLinks
B2B-VideoLinks
More VideoLinks >>>