Article
Engineering, Electrical & Electronic
Jinwoo Lee, Soohyun Kim
Summary: This article introduces an analytical method for measuring the quantitative ratio of components in a mixture using terahertz time-domain spectroscopy (THz-TDS), demonstrating its feasibility in concentration analysis.
IEEE TRANSACTIONS ON INSTRUMENTATION AND MEASUREMENT
(2021)
Article
Multidisciplinary Sciences
Wei Shi, Chunhui Li, Haiqing Wang, Zhiquan Wang, Lei Yang
Summary: Due to the characteristics of THz wave, the terahertz time-domain spectral (THz-TDS) system has potential in the detection of biological macromolecules. The focus of research in this field is to study aqueous samples, as water has a strong absorption effect on THz waves. This study used a THz-TDS system with LiNbO3 crystal to generate strong THz waves and tested alpha-lactose samples with different water contents. The absorption peak at 0.53 THz was detected, and the absorption spectrum shifted upwards with increasing water content. This research guides the testing and improvement of water content limits in this field.
Article
Geochemistry & Geophysics
Hayatomomaru Morimoto, Shouhei Kidera
Summary: This study presents a super-resolution subsurface imaging method based on sparse regularization for multilayer structure analysis in the terahertz band. The depth resolution dependence in optical lens-based measurements can be solved by using an appropriate depth-dependent reference signal.
IEEE GEOSCIENCE AND REMOTE SENSING LETTERS
(2022)
Article
Chemistry, Multidisciplinary
Tom S. Seifert, Ulrike Martens, Florin Radu, Mirkow Ribow, Marco Berritta, Lukas Nadvornik, Ronald Starke, Tomas Jungwirth, Martin Wolf, Ilie Radu, Markus Muenzenberg, Peter M. Oppeneer, Georg Woltersdorf, Tobias Kampfrath
Summary: The anomalous Hall effect (AHE) remains operative from DC up to 40 THz in thin films of technologically relevant magnetic materials, with the large Drude scattering rate of metal thin films smearing out any sharp spectral features of the THz AHE. The intrinsic contribution dominates over the extrinsic mechanisms in the THz AHE for the Co32Fe68 sample, indicating promising potential for future THz spintronic devices operating reliably from DC to 40 Thz.
ADVANCED MATERIALS
(2021)
Article
Physics, Multidisciplinary
Harry W. Baxter, Adam A. Worrall, Jie Pang, Riqing Chen, Bin Yang
Summary: The study demonstrates the capability of using terahertz systems to identify different liquid samples through measuring their THz complex permittivities and analyzing 2D images of volatile liquids with different volumes. The results show promising feasibility for efficiently identifying different volatile liquids using mm-wave imager and THz spectroscopy.
FRONTIERS IN PHYSICS
(2021)
Article
Pharmacology & Pharmacy
Anis Moradikouchi, Anders Sparen, Olof Svensson, Staffan Folestad, Jan Stake, Helena Rodilla
Summary: In this study, the feasibility of using terahertz spectroscopy combined with multivariate analysis for the quantification of API concentration and tablet density in pharmaceutical tablets was explored. The results showed that terahertz spectroscopy can accurately measure tablet density and has lower scattering effects compared to Raman and NIR spectroscopy.
INTERNATIONAL JOURNAL OF PHARMACEUTICS
(2023)
Article
Geochemistry & Geophysics
Hayatomomaru Morimoto, Yoshihiro Yamauchi, Shouhei Kidera
Summary: In this study, a complex permittivity profile reconstruction method for multilayered objects was proposed by combining CS-based thickness estimation with CSI non-linear inverse scattering method, effectively solving the problem of estimating the dielectric constant and thickness of each layer in multiple layers.
IEEE GEOSCIENCE AND REMOTE SENSING LETTERS
(2022)
Article
Instruments & Instrumentation
Ryoichi Kumazawa, Keisuke Sawada, Yoshiharu Toriumi, Masanobu Yoshikawa
Summary: The absorption spectra of the two crystalline forms of 5,5-diethylbarbituric acid were measured using THz-TDS, revealing distinct differences between the two forms. Identification and quantitative analysis of the polymorphs were achieved through THz-TDS, and the ab-initio calculations of vibrational modes based on crystal structures were in good agreement with experimental data. The differences in THz absorption spectra between the two forms are discussed.
APPLIED SPECTROSCOPY
(2022)
Article
Multidisciplinary Sciences
Arne Maes, Camille Pestiaux, Alice Marino, Tim Balcaen, Lisa Leyssens, Sarah Vangrunderbeeck, Grzegorz Pyka, Wim M. De Borggraeve, Luc Bertrand, Christophe Beauloye, Sandrine Horman, Martine Wevers, Greet Kerckhofs
Summary: The authors present a cryogenic contrast-enhanced MicroCT method that improves the visualization of tissue microstructure by freezing stained samples at optimal freezing rates. They successfully applied this method to analyze individual muscle fibers and locate fibrotic regions in murine hearts. This method has significant applications in tissue histology and food preservation.
NATURE COMMUNICATIONS
(2022)
Article
Multidisciplinary Sciences
Nina Elina Hanninen, Timo Liimatainen, Matti Hanni, Olli Grohn, Miika Tapio Nieminen, Mikko Johannes Nissi
Summary: This study evaluated the sensitivity of different tissues' relaxation parameters to the magnetic field orientation and found that highly ordered collagenous tissues exhibit the most prominent relaxation anisotropy, while the effect is less noticeable in other tissues. This highlights the importance of sequence choice and design in MR imaging.
SCIENTIFIC REPORTS
(2022)
Article
Optics
Hui Li, Xulei Qin, Ye Li
Summary: This paper discusses the measurement of terahertz wave intensity using photoconductive antenna and electro-optic sampling, as well as the influence of laser polarizations on the signal-to-noise ratio in THz-TDS. The experimental results emphasize the significance of THz-TDS and highlight the variation of refractive index of GaSe nanofilm at different frequencies in the THz band.
Article
Chemistry, Analytical
Zhengmin Tang, Jianbo Miao, Quancheng Liu, Weiwei Qu, Lichuan Luo, Liping Shang, Hu Deng
Summary: This study utilizes terahertz time domain spectroscopy to measure the optical parameters of aqueous AP samples and constructs five quantitative prediction models. The optimized extreme learning machine model based on the absorption coefficient with the help of chemometrics shows the best prediction results for moisture content. The research provides a reliable basis for accurate prediction of the moisture content of AP and similar substances, paving the way for rapid and non-destructive detection methods.
MICROCHEMICAL JOURNAL
(2021)
Article
Materials Science, Characterization & Testing
Yi-Fan Zhong, Jiao-Jiao Ren, Li-Juan Li, Ji-Yang Zhang, Dan-Dan Zhang, Jian Gu, Jun-Wen Xue, Qi Chen
Summary: A method for monitoring and evaluating the thickness and damage evolution of bonded interfaces in composite structures under cyclic stress using terahertz technology and SIFT image processing algorithm was proposed, providing valuable insights into the effect of stress load on bonding interface damage evolution.
Article
Materials Science, Paper & Wood
Han Wang, Satoru Tsuchikawa, Tetsuya Inagaki
Summary: This study used THz-TDS to investigate the crystallinity of different cellulose-based materials and found that the integrated intensity of detrended spectra correlated positively with the mass fraction of lignin in the samples and ball milling time. By normalizing the integrated intensity, a new index for evaluating crystallinity was proposed.
Article
Spectroscopy
Tao Chen, Lingxiao Yu, Zhi Li, Fangrong Hu, Chuanpei Xu
Summary: Terahertz absorption spectra of coumarin and 6-methylcoumarin were investigated using THz-TDS system and DFT calculations, revealing that the absorption peaks are mainly caused by electrostatic and vdW interactions, showing similar potential energy distribution between them. The study demonstrates the effectiveness of using THz spectroscopy combined with DFT calculations for analyzing weak intermolecular interactions and biomolecules with similar structures.
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
(2021)