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THz Water Transmittance and Leaf Surface Area: An Effective Nondestructive Method for Determining Leaf Water Content

Pagano, Baldacci, Ottomaniello, Dato, Chianucci, Masini, Carelli, Toncelli, Storchi, Tredicucci, Corona
2019 Sensors  
New technologies, such as terahertz quantum cascade lasers (THz-QCLs) have proven to be non-invasive, effective, and accurate tools for measuring and monitoring leaf water content.  ...  This study explores the feasibility of using an advanced THz-QCL device for measuring the absolute leaf water content in Corylus avellana L., Laurus nobilis L., Ostrya carpinifolia Scop., Quercus ilex  ...  Acknowledgments: The authors would like to thank Barbara Gini (Vivai New Plants, Cenaia, Italy) and Vivaio Carabinieri Forestali (Pieve Santo Stefano, Arezzo, Italy) for supplying the plants used in this  ... 
doi:10.3390/s19224838 pmid:31698861 pmcid:PMC6891343 fatcat:2woojmcjijhgnos6hbwhsaxdrq

Review of theoretical methods and research aspects for detecting leaf water content using terahertz spectroscopy and imaging

Fangfang Qu, Pengcheng Nie, Lei Lin, Chengyong Cai, Yong He
2018 International Journal of Agricultural and Biological Engineering  
THz spectroscopy and THz imaging for monitoring leaf water content and describing leaf water distribution.  ...  This paper reviewed the theoretical models for calculating water content in the plant leaves, the methods for eliminating the scattering loss caused by the surface roughness of leaf, the applications of  ...  The theoretical models for nondestructively calculating water content and the methods of eliminating scattering loss of leaf surface were illustrated.  ... 
doi:10.25165/j.ijabe.20181105.3952 fatcat:hjck2vurjza2tf7y7ngewpfi7q

Application of terahertz Gouy phase shift from curved surfaces for estimation of crop yield

John F. Federici, Robert L. Wample, David Rodriguez, Suman Mukherjee
2009 Applied Optics  
The application of terahertz time-domain spectroscopy (THz-TDS) and imaging to differentiate flat and curved surfaces in reflection via the THz Gouy phase shift is demonstrated.  ...  For a THz-TDS system that is aligned for reflection from a flat surface, the presence of a curved surface displaces the image focal plane from the detector plane, resulting in a Gouy phase shift.  ...  Our preliminary work on imaging of other common thin-skinned, high-water-content crops such cherries, blueberries, and plums shows that the THz imaging method can be used to differentiate these fruits  ... 
doi:10.1364/ao.48.001382 pmid:19252640 fatcat:b55zoewyznfgvi5ji6ee6ap2xm

Terahertz imaging system based on a backward-wave oscillator

Adrian Dobroiu, Masatsugu Yamashita, Yuichi N. Ohshima, Yasuyuki Morita, Chiko Otani, Kodo Kawase
2004 Applied Optics  
The alignment procedure for the optical elements is described, and several methods to reduce the etalon effect that are inherent in monochromatic sources are discussed.  ...  A number of preliminary applications are also shown that cover various areas: nondestructive real-time testing for plastic tubes and packaging seals; biological terahertz imaging of fresh, frozen, or freeze-dried  ...  We thank the following individuals for providing us with the tissue samples used in the present research: Takashi Sawai and Yasuhiro Miura of the Iwate Medical University and Minro Watanabe and Junichi  ... 
doi:10.1364/ao.43.005637 pmid:15534995 fatcat:jj5cqsbxxrhonmwmewpszb65hm

Applications of THz Spectral Imaging in the Detection of Agricultural Products

Hongyi Ge, Ming Lv, Xuejing Lu, Yuying Jiang, Guofang Wu, Guangming Li, Li Li, Zhi Li, Yuan Zhang
2021 Photonics  
to water, has been recognized as an efficient and feasible identification tool, which has been widely used for the qualitative and quantitative analyses of agricultural production.  ...  Furthermore, machine learning methods applied in THz spectral imaging are discussed.  ...  Acknowledgments: We are deeply grateful to the reviewers and editors for their invaluable and constructive suggestions and comments that greatly improved the version of this article.  ... 
doi:10.3390/photonics8110518 fatcat:oy5ygcy2ejgwfj46d3fv2md2li

T-ray imaging

D.M. Mittleman, R.H. Jacobsen, M.C. Nuss
1996 IEEE Journal of Selected Topics in Quantum Electronics  
The use of terahertz pulses for imaging has opened new possibilities for scientific and industrial applications in the terahertz frequency range.  ...  In this article, we describe the technology necessary to perform terahertz "T-ray" imaging, novel imaging techniques, and commercial applications of T-ray imaging.  ...  Currently, there is no accepted, nondestructive procedure for measuring the leaf water status of a transpiring plant.  ... 
doi:10.1109/2944.571768 fatcat:k5gulvnb4ndjvlgiqisfpapqxa

Effective Application of ICT in Food and Agricultural Sector — Optical Sensing is Mainly Described —

Takaharu KAMEOKA, Atsushi HASHIMOTO
2015 IEICE transactions on communications  
This paper gives an outline of key technologies necessary for science-based agriculture.  ...  In this paper, the current state and development for the optical sensing for environment and plant are introduced. key words: ICT, optical sensing, infrared spectroscopy, fluorescent X-ray spectroscopy  ...  Acknowledgments This work was supported by the Project "Integration research for agriculture and interdisciplinary fields," Ministry of Agriculture, Fisheries and Forests, Japan.  ... 
doi:10.1587/transcom.e98.b.1741 fatcat:emhiv62u5bdkffve3zxwdq4aqm

Biomedical applications of a real-time terahertz color scanner

Markus Schirmer, Makoto Fujio, Masaaki Minami, Jiro Miura, Tsutomu Araki, Takeshi Yasui
2010 Biomedical Optics Express  
We demonstrated three possible applications of a THz color scanner in the biomedical field: imaging of pharmaceutical tablets, human teeth, and human hair.  ...  These demonstrations indicated the high potential of the THz color scanner for practical applications in the biomedical field.  ...  ., Japan, for preparation of the pharmaceutical tablets and for conducting THz-TDS measurements, and Dr. Masaaki Ashida of Osaka University, Japan, for fruitful discussions on the results.  ... 
doi:10.1364/boe.1.000354 pmid:21258472 pmcid:PMC3018018 fatcat:eq3qc3vzazdchhgvqqtjtorvge

Continuous-Wave THz Imaging for Biomedical Samples

Yaya Zhang, Chuting Wang, Bingxin Huai, Shiyu Wang, Yating Zhang, Dayong Wang, Lu Rong, Yongchang Zheng
2020 Applied Sciences  
Then, we analyse both the advantages and disadvantages of the CW THz imaging methods and the progress of these methods in THz biomedical imaging in recent ten years.  ...  In the past few decades, the applications of terahertz (THz) spectroscopy and imaging technology have seen significant developments in the fields of biology, medical diagnosis, food safety, and nondestructive  ...  The THz intensity of the leaf veins was greater than the surrounding area, which may be related to the difference in water content, density, and tissue structure.  ... 
doi:10.3390/app11010071 fatcat:42ugdctepfb77acbxydzvgeezu

Imaging with terahertz radiation

Wai Lam Chan, Jason Deibel, Daniel M Mittleman
2007 Reports on progress in physics (Print)  
This list has grown in parallel with the development of new technologies and new paradigms for imaging and sensing.  ...  Much of this interest has been inspired by the promise of valuable new applications for terahertz imaging and sensing.  ...  Acknowledgments We would like to express sincere gratitude to each of the individuals who have permitted us to display some version of their data for this review.  ... 
doi:10.1088/0034-4885/70/8/r02 fatcat:haz5vrajenf3pgfwa6z5v5ddby

Millimeter Wave Characterization of a Catadioptric Lens for Imaging Applications

B. Banik, J. Vukusic, J. Stake
2009 IEEE Microwave and Wireless Components Letters  
An example of UTC-PD epitaxial layer optimisation for continuous-wave THz generation at 340 GHz is shown using the HD model.  ...  Cover: THz imaging of a partially dead leaf employing a catadioptric lens coupled WR-10 horn antenna in a transmission-mode CW imaging setup at 108 GHz.  ...  Different parts of the leaf, e.g. veins, introduce different amounts of transmission losses which correspond to their water content.  ... 
doi:10.1109/lmwc.2009.2031997 fatcat:ap3bwujcyngjdgqkzovb5ajav4

A proposal of a semiconductor-integrated self-complementary bow-tie antenna towards a terahertz transmitter

H. Yamakura, Y. Ishiguro, Y. Kato, M. Suhara
2016 2016 41st International Conference on Infrared, Millimeter, and Terahertz waves (IRMMW-THz)  
leaf [3].  ...  Abstract Graphene and carbon nanotube present unique structure and excellent properties, such as high specific surface area, high conductivity, high thermal conductivity, etc., and play an increasingly  ...  When the microparticles migrate to the interface, they are accumulated near the interface, resulting in effective focusing and separation of particles.  ... 
doi:10.1109/irmmw-thz.2016.7758647 fatcat:knvsrtqm6nhx3jbvhhw4drwn5m

LiDAR: An important tool for next-generation phenotyping technology of high potential for plant phenomics?

Yi Lin
2015 Computers and Electronics in Agriculture  
Overall, with LiDAR determined as a key technical constituent, this study pointed out a novel way for developing the next-generation plant phenotyping techniques, which will be helpful for biologists and  ...  At the same time, it has also been realized that the currently-available LiDAR forms cannot effectively support the development of the next-generation techniques of plant phenotyping.  ...  For instance, it is usually hard to diagnose degree of water stress nondestructively, but the LiDAR-based method has proved to allow diagnosing water stress by quantifying the degree of leaf droop via  ... 
doi:10.1016/j.compag.2015.10.011 fatcat:lghwyyqi6vc2xaybqba44dnwhi

Smart Portable Devices Suitable for Cultural Heritage: A Review

Federica Valentini, Andrea Calcaterra, Simonetta Antonaroli, Maurizio Talamo
2018 Sensors  
The new proposed portable contact sensors (directly applied to art work objects and surfaces) are non-invasive and non-destructive to the different materials and surfaces of which cultural heritage is  ...  The review has been prepared in the form of a retrospective description of the sensor's history and technological evolution, having: new nanomaterials for transducers, miniaturized, portable and integrated  ...  to the environmental monitoring of gaseous and PM based pollutants.  ... 
doi:10.3390/s18082434 pmid:30050013 fatcat:6m7s47tawbalvaa66wqx65jqpe

TiO2 Nanotube Arrays: Growth and Application [chapter]

Karthik Shankar
2016 Encyclopedia of Nanotechnology  
These excitations, called surface plasmons (SPs), are determined by the long-range nature of the Coulomb interaction among electrons in metals and show a well-defined frequency/wave vector dispersion described  ...  Synonyms Infrared plasmonics beyond noble metals; Low carrier density materials for infrared plasmonics Definition Collective electronic excitations confined at metal surfaces play a key role in a wide  ...  Some of the prerequisites for an effective optical interferometric sensing material are a large internal surface area, ease of fabrication, and a chemically modifiable surface.  ... 
doi:10.1007/978-94-017-9780-1_382 fatcat:i4ptwbhegbaana43geg7knhrda
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