Terahertz radiation NDE of composite materials for wind turbine applications

Je-Woong Park, Kwang-Hee Im, In-Young Yang, Sun-Kyu Kim, Sung-Jun Kang, Young-Tae Cho, Jong-An Jung, David Kuei Hsu

Abstract

Nondestructive testing technique using T-ray (terahertz ray) has received more interest as a new capability tool in engineering application. So, T-ray time-domain spectroscopy was used for inspecting and evaluating physical property and defect characteristics in FRP composite materials for a use of wind energy. First of all, a general refraction mode and transmission mode was utilized for calculating a refractive index (n) based on the well-machined sample. In order to obtain the terahertz ray refractive index, a refractive mode and a transmission mode technique was defined for solving a refractive coefficient (n), with which refractive index of GFRP composites, balsa and epoxy for a use of wind turbine blades could be obtained. A method of wind turbine blade composites having one and two saw-cuts delaminations and some angles/directions was suggested based on the E-field vector. The time of flight in T-ray using evaluating a T-ray transmission mode agreed with that using T-ray time-domain spectroscopy with the wind turbine blade. Also, in CFRP composites, T-ray propagation is limited because the carbon fibers are blocking the T-ray. Therefore, we have analyzed difference between E-field vector in T-ray and the carbon fiber direction. Also, it was found that a T-ray time domain data in thick GFRP composite laminates seemed to show peaks with a regular spacing (Δt) which was obvious with the close relation between TOF and FFT.

This study was performed using TeraView's TPS spectra 3000 system. (TeraView, Cambridge, UK)

Full Article: http://link.springer.com/article/10.1007/s12541-014-0464-0

Detection of Melamine in Foods Using Terahertz Time-Domain Spectroscopy

Seung Hyun Baek, Heung Bin Lim, and Hyang Sook Chun

Abstract

The aim of this study was to investigate the feasibility of detecting melamine in foodstuffs using terahertz imaging. The terahertz (THz) spectra and images of melamine mixtures were obtained in the frequency range of 0.1–3 THz at room temperature using THz time-domain spectroscopy. Characteristic absorption peaks of melamine were found at 2, 2.26, and 2.6 THz, and these peaks showed the same frequencies in the different food matrices. At 2 THz, the THz images of melamine were dose-dependently distinguishable from those of food components with or without the packaging materials used. The calibration curve of melamine showed a regression coefficient (R2) of >0.913 and a detection limit of <13%. These results suggest that terahertz imaging has the potential to be used for the qualitative detection of melamine in food as a nondestructive analytical tool.

This study was performed using TeraView's TPS spectra 3000 system. (TeraView, Cambridge, UK)

Full Article: http://pubs.acs.org/doi/abs/10.1021/jf501170z

Terahertz and Raman spectra of non-centrosymmetrical organic molecular crystals

Monika Trzebiatowska-Gusowska, Edward F. Plinski, Jan Baran, Michal J. Walczakowski, Przemyslaw P. Jarzab, Kacper Nowak, Boguslaw Fuglewicz, Martin Mikulics, Norbert Palka, Mieczyslaw Szustakowski

Abstract

The terahertz waves have been applied to the spectroscopy of molecular crystals. The group based on hybrid organic–inorganic crystals like triglycine zinc chloride, triglycine sulphate, triglycine selenate, diglycine hydrobromide, diglycine hydrochloride, diglycine lithium nitrate, glycine lithium nitrate has been considered. The dispersion relation phonon–polariton have been shown between 10 cm−1 and 80 cm−1 for diglycine lithium nitrate, triglycine zinc chloride, and diglycine hydrobromide.

This study was performed using TeraView's TPS spectra 3000 system. (TeraView, Cambridge, UK)

Full Article: http://www.sciencedirect.com/science/article/pii/S0925346714001992

TeraView at Photonex Cambridge 2014

TeraView are pleased to announce that we will be attending Photonex Cambridge 2014!

The event will be held at the Robinson Collage Cambridge, on the 18th of June 2014

Photonex Cambridge brings together the UK's top photonics technology companies, leading researchers and invited speakers for a very special one-day event. There is an exhibition of 25 companies dedicated to optics, photonics and imaging technology, allowing you to view latest photonics applications and solutions. As well as a conference all about the latest techniques.

TeraViews Dr Alessia Portieri will be attending, as well as presenting a talk at 10:30 titled:
Intra-operative Terahertz Probe for Detection of Breast Cancer

For more information on the event please visit the event website: http://www.photonex.org/cambridge/

Oral Presentation at IRMMW-THz 2014 - Terahertz Car Paint Thickness Sensor: Out Of The Lab And Into The Factory

TeraView are pleased to announce that Rob May has had an abstract accepted for oral presentation at IRMMW-THz 2014!

The paper is titled: Terahertz Car Paint Thickness Sensor: Out Of The Lab And Into The Factory

Oral presentations have been assigned a 15 minute duration, including discussion, and we will be posting the time and date of the presentation as soon as we are informed.

If you would like to prearrange a meeting with TeraView at the event please contact Phil Taday. For more information regarding IRMMW-THz 2014 please visit the event webpage.