Flying at Speeds up to Mach 17

University of Central Florida (UCF) researchers are building on their technology that could pave the way for hypersonic flight, such as travel from New York to Los Angeles in under 30 minutes.

In their latest research published Monday in the journal Proceedings of the National Academy of Sciences, the researchers discovered a way to stabilize the detonation needed for hypersonic propulsion by creating a special hypersonic reaction chamber for jet engines.

There is an intensifying international effort to develop robust propulsion systems for hypersonic and supersonic flight that would allow flight through our atmosphere at very high speeds and also allow efficient entry and exit from planetary atmospheres,” says study co-author Kareem Ahmed, an associate professor in UCF’s Department of Mechanical and Aerospace Engineering. “The discovery of stabilizing a detonation — the most powerful form of intense reaction and energy release — has the potential to revolutionize hypersonic propulsion and energy systems.”

The system could allow for air travel at speeds of Mach 6 to 17, which is more than 4,600 to 13,000 miles per hour. The technology harnesses the power of an oblique detonation wave, which they formed by using an angled ramp inside the reaction chamber to create a detonation-inducing shock wave for propulsionUnlike rotating detonation waves that spin, oblique detonation waves are stationary and stabilized. The technology improves jet propulsion engine efficiency so that more power is generated while using less fuel than traditional propulsion engines, thus lightening the fuel load and reducing costs and emissions.

In addition to faster air travel, the technology could also be used in rockets for space missions to make them lighter by requiring less fuel, travel farther and burn more cleanly.


How To Early Detect Prostate Cancer

For the first time, a team of scientists at the University of Central Florida has created functional nanomaterials with hollow interiors that can be used to create highly sensitive biosensors for early cancer detection. Xiaohu Xia, an assistant professor of chemistry with a joint appointment in the NanoScience Technology Center, and his team developed the new method and recently published their work in the journal ACS Nano.

These advanced hollow nanomaterials hold great potential to enable high-performance technologies in various areas,” says Xia. “Potentially we could be talking about a better and less expensive diagnostic tool, sensitive enough to detect biomarkers at low concentrations, which could make it invaluable for early detection of cancers and infectious diseases.”

Because hollow nanomaterials made of gold and silver alloys display superior optical properties, they could be particularly good for developing better test strip technology, similar to over-the-counter pregnancy tests. Currently the technology used to indicate positive or negative symbols on the test stick is not sensitive enough to pick up markers that indicate certain types of cancer. But Xia’s new method of creating hollow nanomaterials could change that. More advance warning could help doctors save more lives.

In conventional test strips, solid gold nanoparticles are often used as labels, where they are connected with antibodies and specifically generate color signal due to an optical phenomenon called localized surface plasmon resonance. Under Xia’s technique, metallic nanomaterials can be crafted with hollow interiors. Compared to the solid counterparts, these hollow nanostructures possess much stronger LSPR activities and thus offer more intense color signal. Therefore, when the hollow nanomaterials are used as labels in test strips they can induce sensitive color change, enabling the strips to detect biomarkers at lower concentrations.

Test-strip technology gets upgraded by simply replacing solid gold nanoparticles with the unique hollow nanoparticles, while all other components of a test strip are kept unchanged,” says Xia. “Just like the pregnancy test, the new test strip can be performed by non-skilled persons, and the results can be determined with the naked eye without the need of any equipment. These features make the strip extremely suitable for use in challenging locations such as remote villages.”

The UCF study focused on prostate-specific antigen, a biomarker for prostate cancer. The new test strip based on hollow nanomaterials was able to detect PSA as low as 0.1 nanogram per milliliter (ng/mL), which is sufficiently sensitive for clinical diagnostics of prostate cancer. The published study includes electron microscope images of the metallic hollow nanomaterials.

“I hope that by providing a general and versatile platform to engineer functional hollow nanomaterials with desired properties, new research with the potential for other applications beyond biosensing can be launched,” Xia says.