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1 2 A D V A N C E D M A T E R I A L S & P R O C E S S E S | O C T O B E R 2 0 1 9 often relies on nondestructive ultra- sonic instruments. A new approach marks one of the first nondestructive testing (NDT) systems that combines elements of contact and noncontact ultrasound testing. A team of researchers from North Carolina State University, Raleigh, and the Korea Military Academy is using ultrasonic NDT that involves amplifying the signal from a photo- acoustic laser source using a laser- absorbing patch made from an array of nanoparticles from candle soot and polydimethylsiloxane. The results of generating such ultrasonic waves with the photoacous- tic patch demonstrate the promise of the broad range of noncontact applica- tions for NDT. By placing the particle in the patch in a line array, they were able to narrow the bandwidth of the waves, filtering out unwantedwave signals and increas- ing analytical accuracy. The researchers opted for an aluminum sensing system for the receiving transducer. The patch increased the amplitude by more than twofold over conditions without the patch and confirmed it pro- duced narrower bandwidth than other conditions. The researchers say the question of how the approach’s dura- bility in an industrial setting remains, as well as howwell the patches perform on curved and rough surfaces. Next, the team plans to test the system in high-temperature NDT sce- narios. ncsu.edu . TESTING | CHARACTERIZATION VIBRATION MAPPING EXCITES THE WORLD OF NANOSPECTROSCOPY A team of researchers from the University of Vienna, Austria, in collab- oration with the Advanced Institute of Science and Technology, Japan, and La Sapienza University, Italy, have devel- oped a new method for measuring existing phonons in a nanostructured material. The technique represents a breakthrough in the analysis and opti- mization of nanoscale functional mate- rials and devices. Important thermal, mechanical, optoelectronic, and transport char- acteristics of materials are ruled by phonons, or propagating atomic vibra- tional waves. Currently available tech- niques involve optical methods as well as inelastic electron, x-ray, and neu- tron-scattering. None of these meth- Binghamton University, N.Y., will acquire a sophisticated new x-ray tool useful in materials research and R&D for electronics. The $1.75 million system—the first of its kind outside of Europe—will be funded in part by the National Science Foundation’s Major Research Instru- mentation program. The instrument, a hard x-ray photoelectron spectros- copy system (or HAXPES), allows researchers to get detailed information about a device or material without taking it apart. binghamton.edu . BRIEFS Automated Precision Inc. (API), Rockville, Md., has acquired Exact Laser Measurements, Canada. According to API, the move will strengthen its metrology ser- vices offerings, particularly in the automotive and aerospace markets. API develops laser-based equipment for measurement and calibration. apisensor.com. ods have been able to determine all phonons of a freestanding mono- layer of 2Dmaterials such as graphene and their local variations within a graphene nanoribbon, which are in turn used as active elements in nano and optoelectronics. Now, an interna- tional research team of leading experts in electron spectros- copy has presented an original method and applied it to graphene nanostruc- tures as a model. For the first time, they were able to determine all vibrational modes of freestanding graphene as well as the local extension of different vibrational modes in a graphene nanoribbon. This new method, which they’re calling “large q mapping,” opens entirely new possibilities to determine the spatial and momentum extension of phonons in all nanostructured as well as 2D advanced materials. This study of high q-mapping of vibrations in the electron microscope opens a new pathway of nanospectros- copy of all materials combining spa- tial and momentum resolved measure- ments. www.univie.ac.at/en. CANDLE SOOT AIDS LASER- BASED ULTRASONIC NDT Monitoring structural integrity in industrial buildings, including nuclear power plants and chemical plants, Graphic depiction of a wavefront of transmitted fast electrons causing excitable local lattice vibrations in graphene. Courtesy of Ryosuke Senga/AIST.