Device Can Identify a Wide Range of Airborne Gases and Chemicals Instantly
Scientists at Nanyang Technological University, Singapore (NTU Singapore), have developed a portable device that can identify airborne hazards from tiny gas molecules like sulphur dioxide to larger compound molecules like benzene, that are harmful to human health. The device provides real-time monitoring of air quality and assists in the detection of gas leaks and industrial air pollution. The research team was led by Associate Professor Ling Xing Yi at the School of Physical and Mathematical Sciences.
The new technology, the researchers note, eliminates the need to collect air samples, as is necessary when using gas chromatography, or mass spectrometry, the laboratory method currently used to identify gases in the air. Although this method is reliable, it takes from a few hours to a few days to obtain the results. The new approach provides a fast and ongoing analysis of potential air contamination, enabling emergency responders to expedite appropriate action at incidents such as natural disasters, chemical spills, or illegal dumping of toxic waste.
How It Works
A small patch of a special porous and metallic nanomaterial traps the gas molecules. A laser is shone on it from a few meters away. The interaction of the light with the gas molecules causes the emission of a light of a lower energy. The spectroscopic readout (a graph chart) acts like a ‘chemical fingerprint’ that corresponds to various chemicals present on the patch. The whole process takes about 10 seconds. The sample’s chemical fingerprints are referenced against a digital library of fingerprints to quickly determine what chemicals have been detected.
The new system uses Raman spectroscopy, which has long been used to identify chemical substances, but only solid and liquid samples; gaseous chemicals are too dilute for the laser and detector to pick up. To overcome this limitation, Ling and Phan Quang Gia Chuong, a PhD student, developed a nanostructure made of a highly porous synthetic material known as a ‘metal-organic framework,’ which actively absorbs and traps molecules from the air into a ‘cage.’ Metal nanoparticles in this nanostructure boost the intensity of the light surrounding the molecules and enhance the Raman spectroscopy signals a million-fold, making it possible to identify the trapped molecules.
Ling, head of the Division of Chemistry & Biological Chemistry at NTU, explains that the device can work remotely so personnel can operate the laser camera and analyze the chemicals at a safe distance. The laser was tested to work up to 10 meters away and can be engineered to reach farther distances.
In experiments, the device identified airborne molecules such as polyaromatic hydrocarbons (PAHs), including naphthalene and derivatives of benzene, a family of colorless industrial air pollutants known to be highly carcinogenic. It can detect PAHs at parts-per-billion concentrations in the atmosphere as well as continuously monitor the concentration of the different types of gases like carbon dioxide in the atmosphere.
The team has filed for a patent and is commercializing the technology for use in pollution monitoring, chemical disaster response, and other industrial applications.
Story Source: Materials provided by Nanyang Technological University. Journal Reference: Gia Chuong Phan-Quang, Ningchen Yang, Hiang Kwee Lee, Howard Yi Fan Sim, Charlynn Sher Lin Koh, Ya-Chuan Kao, Zhao Cai Wong, Eddie Khay Ming Tan, Yue-E Miao, Wei Fan, Tianxi Liu, In Yee Phang, Xing Yi Ling. Tracking Airborne Molecules from Afar: Three-Dimensional Metal–Organic Framework-Surface-Enhanced Raman Scattering Platform for Stand-Off and Real-Time Atmospheric Monitoring. ACS Nano, 2019; DOI: 10.1021/acsnano.9b06486. “Airborne chemicals instantly identified using new technology,” Nanyang Technological University. ScienceDaily. www.sciencedaily.com/releases/2019/10/191015171556.htm (accessed October 17, 2019).
Competition seeks Innovative Methods for Rapidly Detecting and Extinguishing Wildfires
XPRIZE and California Governor Gavin Newsom are collaborating to design an XPRIZE competition to encourage the submission of innovative methods for rapidly detecting and extinguishing wildfires. XPRIZE designs and operates multimillion-dollar global competitions to solve humanity’s grand challenges and believes that solutions to the world’s problems can come from anyone, anywhere, according to its company identification statement.
XPRIZE and Newsom will work in collaboration with stakeholders, including the Governor’s team, while also actively seeking sponsors to underwrite the prize purse and operations. It is anticipated that the competition will be initiated by early 2020.
“Wildfires cause damage to human lives and billions of dollars in property loss each year, yet there has been shockingly little innovation in this space,” says Dr. Peter H. Diamandis, XPRIZE founder and executive chairman. “XPRIZE wants to reinvent what has been an old form of firefighting. This competition hopes to leverage cutting edge sensors, networks, artificial intelligence, robotics and material sciences to both detect wildfires at their earliest inception and extinguish them before they spread.”
Newsom explains: “Harnessing the power of competition to drive innovation, the XPRIZE will focus on solutions to the existential threat of wildfires. I am proud to stand with XPRIZE as they launch this competition. The XPRIZE will complement California’s spirit of innovation and promote leading-edge solutions to address wildfires.”
Dr. Richard Merkin, CEO of Heritage Group and a longtime XPRIZE benefactor and Vision Circle member, provided the funding to develop this XPRIZE concept, including the background research, the development of competition rules, and operating guidelines. Additional information is at https://xprize.org/, or from Eric Desatnik at
Study: ‘Fire blankets can protect buildings from wildfires, but advancements needed for severe situations’
“Existing blanket technology can protect an isolated building from a short wildfire attack, but technological advancements are needed for severe situations,” says Fumiaki Takahashi, a professor at Case Western Reserve University, Cleveland, Ohio, and the lead researcher of a study conducted in conjunction with the NASA Glenn Research Center, U.S. Forest Service, New Jersey Forest Fire Service, and Cuyahoga Community College.
Takahashi also noted: “Fire blanket protection will be significant to those living and fighting fires at the wildland urban interface and presents entrepreneurs and investors with business opportunities. The implication of the present findings is that the technical community, the general public, and the fire service must work together to take a step-by-step approach toward the successful application of this technology.”
In the study, fabric materials were rigorously tested in the laboratory and used as shields for structures exposed to fires of increasing magnitude. The research was published in Frontiers in Mechanical Engineering.
Although the studyconfirmed that existing blanket technology can protect structures from a short wildfire attack, it also revealed that to be effective against severe fires and in areas of high housing density, technological advancements were needed in blanket materials, deployment methods, and multistructure protection strategies.
Takahashi’s research found a severe lack of scientific evidence to back up anecdotal reports on the ability of fire blankets to protect buildings from fires. This led his team to conduct several experiments to determine how well various blanket materials would shield structures against fires of increasing magnitude. These tests were funded by a research grant from the U.S. Department of Homeland Security.
The team conducted fire exposure tests on various wooden structures, from a birdhouse in a burning room to a full-size shed in an actual forest fire. Four types of fabric materials–aramid, fiberglass, amorphous silica, and pre-oxidized carbon–were tested, each with and without an aluminum surface.
Also, Takahashi explains, “The team conducted laboratory experiments under controlled heat exposure and measured the heat-insulation capabilities of these materials against direct flame contact or radiation heat. The fiberglass or amorphous silica fabrics laminated with aluminum foil performed best, due to high reflection/emission of radiation and good thermal insulation by the fabric. New technology is needed to enhance the fire blankets’ heat-blocking capability for an extended period to prevent structure-to-structure ignition. In addition, it will be more effective if dozens or hundreds of homes are protected by such advanced fire blankets at the same time, particularly in high housing-density Wildland Urban Interface communities.”
He suggests that communities potentially affected by wildfires work together ‘to turn the concept of whole-building fire blankets into a reality.’ The original research article is at https://www.frontiersin.org/articles/10.3389/fmech.2019.00060/. Professor Fumiaki Takahashi may be reached [email protected]/.
MARY JANE DITTMAR is senior associate editor of Fire Engineering and conference manager of FDIC International. Before joining the magazine in January 1991, she served as editor of a trade magazine in the health/nutrition market and held various positions in the educational and medical advertising fields. She has a bachelor’s degree in English/journalism and a master’s degree in communication arts.