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  • Article
  • Open Access
7 Citations
2,693 Views
13 Pages

Second Harmonic Scattering of Molecular Aggregates

  • Guillaume Revillod,
  • Julien Duboisset,
  • Isabelle Russier-Antoine,
  • Emmanuel Benichou,
  • Christian Jonin and
  • Pierre-François Brevet

27 January 2021

A general model is developed to describe the polarization-resolved second harmonic scattering (SHS) response from a liquid solution of molecular aggregates. In particular, the molecular spatial order is introduced to consider the coherent contributio...

  • Article
  • Open Access
1 Citations
2,352 Views
12 Pages

Dual-Wavelength Forward-Enhanced Directional Scattering and Second Harmonic Enhancement in Open-Hole Silicon Nanoblock

  • Xinghua Wang,
  • Yunbao Zheng,
  • Min Ouyang,
  • Haihua Fan,
  • Qiaofeng Dai and
  • Haiying Liu

30 November 2022

Nanostructures with appropriate sizes can limit light-matter interaction and support electromagnetic multipole resonance. The interaction between light and nanostructures is intimately related to manipulating the direction of scattered light in the f...

  • Article
  • Open Access
7 Citations
4,961 Views
8 Pages

Simultaneous Second-Harmonic, Sum-Frequency Generation and Stimulated Raman Scattering in MgO:PPLN

  • Dismas K. Choge,
  • Huaixi Chen,
  • Lei Guo,
  • Guangwei Li and
  • Wanguo Liang

13 November 2018

In this study, simultaneous second-harmonic generation (SHG), sum frequency generation (SFG), and Raman conversion based on MgO-doped periodically poled lithium niobate (MgO:PPLN) for multi-wavelength generation is demonstrated. The approach used is...

  • Article
  • Open Access
6 Citations
2,261 Views
6 Pages

Second-Harmonic Generation in Aggregates of Lithium Niobate Particles Formed upon Suspension Freezing

  • Anton A. Matrokhin,
  • Mikhail A. Shevchenko,
  • Sofia F. Umanskaya,
  • Maria V. Tareeva,
  • Anna D. Kudryavtseva and
  • Nikolay V. Tcherniega

28 September 2022

This paper demonstrates a significant increase in the efficiency of second-harmonic generation in a suspension of lithium niobate (LiNbO3) particles during freezing at nano and picosecond pum pulse durations. The amplification is caused by the format...

  • Review
  • Open Access
5 Citations
5,255 Views
18 Pages

22 January 2021

By eliminating the photodamage and photobleaching induced by high intensity laser and fluorescent molecular, the label-free laser scanning microscopy shows powerful capability for imaging and dynamic tracing to biological tissues and cells. In this r...

  • Article
  • Open Access
10 Citations
4,539 Views
11 Pages

22 January 2023

The accurate evaluation of nonlinear optical (NLO) coefficient, the main parameter affecting light conversion efficiency, plays a crucial role in the development of NLO materials. The Kurtz–Perry powder technique can evaluate second-harmonic ge...

  • Article
  • Open Access
27 Citations
4,003 Views
18 Pages

In Vitro Study of Extracellular Vesicles Migration in Cartilage-Derived Osteoarthritis Samples Using Real-Time Quantitative Multimodal Nonlinear Optics Imaging

  • Leonardo Mortati,
  • Laura de Girolamo,
  • Carlotta Perucca Orfei,
  • Marco Viganò,
  • Marco Brayda-Bruno,
  • Enrico Ragni and
  • Alessandra Colombini

Mesenchymal stromal cells (MSCs)-derived extracellular vesicles (EVs) are promising therapeutic nano-carriers for the treatment of osteoarthritis (OA). The assessment of their uptake in tissues is mandatory but, to date, available technology does not...

  • Review
  • Open Access
5 Citations
3,464 Views
18 Pages

16 October 2024

The World Health Organization (WHO) cancer agency predicts that more than 35 million cases of cancer will be experienced in 2050, a 77% increase over the 2022 estimate. Currently, the main cancers diagnosed are breast, lung, and colorectal. There is...

  • Article
  • Open Access
3 Citations
1,745 Views
13 Pages

Second-Order Nonlinearity of Graphene Quantum Dots Measured by Hyper-Rayleigh Scattering

  • Manoel L. Silva-Neto,
  • Renato Barbosa-Silva,
  • Georges Boudebs and
  • Cid B. de Araújo

27 November 2023

The first hyperpolarizability of graphene quantum dots (GQDs) suspended in water was determined using the hyper-Rayleigh scattering (HRS) technique. To the best of our knowledge, this is the first application of the HRS technique to characterize GQDs...

  • Feature Paper
  • Article
  • Open Access
39 Citations
8,973 Views
21 Pages

“Seeing Is Believing”—In-Depth Analysis by Co-Imaging of Periodically-Poled X-Cut Lithium Niobate Thin Films

  • Sven Reitzig,
  • Michael Rüsing,
  • Jie Zhao,
  • Benjamin Kirbus,
  • Shayan Mookherjea and
  • Lukas M. Eng

15 March 2021

Nonlinear and quantum optical devices based on periodically-poled thin film lithium niobate (PP-TFLN) have gained considerable interest lately, due to their significantly improved performance as compared to their bulk counterparts. Nevertheless, perf...

  • Feature Paper
  • Article
  • Open Access
24 Citations
6,197 Views
11 Pages

Highly-Efficient Longitudinal Second-Harmonic Generation from Doubly-Resonant AlGaAs Nanoantennas

  • Lei Xu,
  • Mohsen Rahmani,
  • Daria Smirnova,
  • Khosro Zangeneh Kamali,
  • Guoquan Zhang,
  • Dragomir Neshev and
  • Andrey E. Miroshnichenko

17 September 2018

We design an asymmetric nonlinear optical nanoantenna composed of a dielectric nanodisc and an adjacent nanobar. The proposed composite structure made of AlGaAs exhibits resonant response at both the fundamental and doubled frequencies. Being driven...

  • Article
  • Open Access
1 Citations
3,269 Views
9 Pages

14 April 2022

Second harmonic generation has been widely applied in various fields. High second harmonic intensity can facilitate optical imaging, signal sensing, and detection. Thus, enhancing the intensity of the second harmonic is a significant work. However, c...

  • Feature Paper
  • Article
  • Open Access
17 Citations
4,977 Views
15 Pages

Second-Harmonic Generation in Mie-Resonant GaAs Nanowires

  • Domenico de Ceglia,
  • Luca Carletti,
  • Maria Antonietta Vincenti,
  • Costantino De Angelis and
  • Michael Scalora

16 August 2019

We investigate the enhancement of second-harmonic generation in cylindrical GaAs nanowires. Although these nanostructures confine light in two dimensions, power conversion efficiencies on the order of 10 5 with a pump peak inten...

  • Technical Note
  • Open Access
2,848 Views
17 Pages

Nonlinear Cylindrical Markers Using Metamaterials

  • Diana V. Semenikhina and
  • Nikolay N. Gorbatenko

9 December 2021

In this paper, the research of nonlinear cylindrical metastructure was obtained. An algorithm for finding the total field of a nonlinearly loaded perfectly conducting cylinder covered with a metamaterial (MM) layer based on Maxwell’s equations...

  • Communication
  • Open Access
3,272 Views
9 Pages

Localization phenomena in light, scattering from random fluctuations of matter fields and space–time metrics near a black hole horizon, were predicted to produce a pronounced peak in the angular distribution of second-harmonic light in the dire...

  • Article
  • Open Access
6 Citations
8,770 Views
10 Pages

Phase-Insensitive Scattering of Terahertz Radiation

  • Mihail Petev,
  • NiclasWesterberg,
  • Eleonora Rubino,
  • Daniel Moss,
  • Arnaud Couairon,
  • François Légaré,
  • Roberto Morandotti,
  • Daniele Faccio and
  • Matteo Clerici

The nonlinear interaction between Near-Infrared (NIR) and Terahertz pulses is principally investigated as a means for the detection of radiation in the hardly accessible THz spectral region. Most studies have targeted second-order nonlinear processes...

  • Article
  • Open Access
12 Citations
2,638 Views
13 Pages

Scattering of Ultrashort X-ray Pulses by Various Nanosystems

  • Marat Eseev,
  • Andrey Goshev and
  • Dmitry Makarov

10 July 2020

Currently, the study of the scattering of ultrashort X-ray pulses (USPs) by various objects is an urgent task, in connection with the creation of powerful sources of USP generation. In this paper, the theory of the scattering of attosecond pulses by...

  • Proceeding Paper
  • Open Access
1 Citations
1,255 Views
7 Pages

Arylthienyl-vinyl-benzothiazoles as Efficient Second Harmonic Generators (SHG) for Nonlinear Optics

  • Rosa M. F. Batista,
  • Susana P. G. Costa,
  • Michael Belsley and
  • M. Manuela M. Raposo

14 November 2018

New push-pull second harmonic generation (SHG) chromophores 2 were synthesized in order to study their linear and nonlinear optical properties. The donor-acceptor π-conjugated systems 2 were prepared in good to excellent yields by a simple aldol-type...

  • Article
  • Open Access
2 Citations
1,815 Views
8 Pages

19 July 2024

The measurement problem of quantum mechanics concerns the question as to under which circumstances coherent wave evolution becomes disrupted to produce eigenstates of observables, instead of evolving superpositions of eigenstates. The problem already...

  • Article
  • Open Access
86 Citations
9,167 Views
6 Pages

7 June 2011

Multiple wavelength light sources in the medical spectral window region are useful for various medical sensing applications in tissue by distinguishing the absorption and scattering coefficients optically. We propose a simultaneous second harmonic ge...

  • Review
  • Open Access
37 Citations
6,498 Views
18 Pages

Zinc(II) as a Versatile Template for Efficient Dipolar and Octupolar Second-Order Nonlinear Optical Molecular Materials §

  • Santo Di Bella,
  • Alessia Colombo,
  • Claudia Dragonetti,
  • Stefania Righetto and
  • Dominique Roberto

11 December 2018

This short review outlines the main results obtained in the field of molecular materials based on zinc coordination compounds for second-order nonlinear optics. It presents an overview of the main classes of second-order nonlinear optical (NLO) activ...

  • Article
  • Open Access
3 Citations
3,071 Views
16 Pages

An Open Access Chamber Designed for the Acoustic Characterisation of Microbubbles

  • Elliott Smith,
  • Luzhen Nie,
  • James McLaughlan,
  • Harry Clegg,
  • Thomas Carpenter,
  • David Cowell,
  • Stephen Evans,
  • Alejandro F. Frangi and
  • Steven Freear

10 February 2022

Microbubbles are used as contrast agents in clinical ultrasound for Left Ventricular Opacification (LVO) and perfusion imaging. They are also the subject of promising research in therapeutics as a drug delivery mechanism or for sonoporation and co-ad...

  • Article
  • Open Access
1,584 Views
14 Pages

Multiwave Matrix Polarization Lidar

  • Sergei N. Volkov,
  • Ilia D. Bryukhanov,
  • Ignatii V. Samokhvalov,
  • Duk-Hyeon Kim and
  • Youngmin Noh

29 October 2023

Remote control of the state of the atmosphere is an urgent problem nowadays. The problem of remote monitoring of the optical parameters of the atmosphere is solved using a matrix polarization lidar (MPL). The scattering matrix obtained from polarizat...

  • Review
  • Open Access
27 Citations
6,991 Views
12 Pages

The DIVER Microscope for Imaging in Scattering Media

  • Alexander Dvornikov,
  • Leonel Malacrida and
  • Enrico Gratton

We describe an advanced DIVER (Deep Imaging Via Emission Recovery) detection system for two-photon fluorescence microscopy that allows imaging in multiple scattering media, including biological tissues, up to a depth of a few mm with micron resolutio...

  • Proceeding Paper
  • Open Access
1,974 Views
2 Pages

Computation of Resonance Modes in Open Cavities with Perfectly Matched Layers

  • Luis M. Hervella-Nieto,
  • Andrés Prieto and
  • Sara Recondo

During the last decade, several authors have addressed that the Perfectly Matched Layers (PML) technique can be used not only for the computation of the near-field in time-dependent and time-harmonic scattering problems, but also to compute numerical...

  • Article
  • Open Access
1 Citations
1,461 Views
11 Pages

Gold Nanoparticles at a Liquid Interface: Towards a Soft Nonlinear Metasurface

  • Delphine Schaming,
  • Anthony Maurice,
  • Frédéric Gumy,
  • Micheál D. Scanlon,
  • Christian Jonin,
  • Hubert H. Girault and
  • Pierre-François Brevet

23 August 2024

Optical second-harmonic generation (SHG) is achieved using adsorbed gold nanoparticles (AuNPs) with an average diameter of 16 nm at the aqueous solution–air interface in reflection. A detailed analysis of the depth profile of the SHG intensity...

  • Article
  • Open Access
5 Citations
4,060 Views
17 Pages

11 November 2020

A spectral acceleration approach for the spherical harmonics discrete ordinate method (SHDOM) is designed. This approach combines the correlated k-distribution method and some dimensionality reduction techniques applied on the optical parameters of a...

  • Article
  • Open Access
15 Citations
3,108 Views
15 Pages

19 June 2021

The surface plasmon resonances of a monolayer graphene disk, excited by an impinging plane wave, are studied by means of an analytical-numerical technique based on the Helmholtz decomposition and the Galerkin method. An integral equation is obtained...

  • Article
  • Open Access
34 Citations
5,025 Views
19 Pages

Nonlinear Optical Materials: Predicting the First-Order Molecular Hyperpolarizability of Organic Molecular Structures

  • Francisco A. Santos,
  • Carlos E. R. Cardoso,
  • José J. Rodrigues,
  • Leonardo De Boni and
  • Luis M. G. Abegão

Experimental nonlinear optics (NLO) is usually expensive due to the high-end photonics and electronic devices needed to perform experiments such as incoherent second harmonic generation in liquid phase, multi-photon absorption, and excitation. Nevert...

  • Article
  • Open Access
7 Citations
4,686 Views
22 Pages

11 February 2020

This study extends the second-order attenuation (SOA) model for elastic waves in texture-free inhomogeneous cubic polycrystalline materials with equiaxed grains to textured polycrystals with ellipsoidal grains of arbitrary crystal symmetry. In term o...

  • Article
  • Open Access
8 Citations
3,605 Views
10 Pages

High-Peak-Power Passively Q-Switched Laser at 589 nm with Intracavity Stimulated Raman Scattering

  • Jian-Cheng Chen,
  • Yu-Wen Ho,
  • Yueh-Chi Tu,
  • Hsing-Chih Liang and
  • Yung-Fu Chen

16 February 2023

A novel scheme was developed for a diode-pumped passively Q-switched Nd:YVO4/KGW Raman laser at 589 nm with a diode-to-orange conversion efficiency reaching 11.4%. The compact near-concentric cavity was designed to achieve the criterion of good passi...

  • Article
  • Open Access
9 Citations
6,658 Views
13 Pages

18 November 2018

A series of π-conjugated molecules, based on pyridazine and thiophene heterocycles 3ae, were synthesized using commercially, or readily available, coupling components, through a palladium catalyzed Suzuki-Miyaura cross-coupling reaction. Th...

  • Review
  • Open Access
31 Citations
7,705 Views
35 Pages

Information on the penetration depth, pathways, metabolization, storage of vehicles, active pharmaceutical ingredients (APIs), and functional cosmetic ingredients (FCIs) of topically applied formulations or contaminants (substances) in skin is of gre...

  • Article
  • Open Access
5 Citations
1,868 Views
16 Pages

3 September 2021

In this paper, the scattering of a plane wave from a lossy Fabry–Perót resonator, realized with two equiaxial thin resistive disks with the same radius, is analyzed by means of the generalization of the Helmholtz–Galerkin regularizing technique recen...

  • Article
  • Open Access
6 Citations
3,606 Views
11 Pages

Plasmon Enhanced Second Harmonic Generation from ZnO Nanofilms on Vertical Au Nanorod Arrays

  • Qiang Ma,
  • Chengda Pan,
  • Yingxian Xue,
  • Zhiyun Fang,
  • Shiyu Zhang,
  • Botao Wu and
  • E Wu

2 October 2021

Vertically aligned gold nanorod arrays have attracted much attention for their fascinating optical properties. Different from longitudinal surface plasmon wavelength (LSPW) and edge-to-edge spacing of gold nanorods, the role of gold nanorod diameter...

  • Article
  • Open Access
6 Citations
6,906 Views
22 Pages

17 February 2016

The propagation of small perturbations in complex geometries can involve hydrodynamic-acoustic interactions, coupling acoustic waves and vortical modes. A propagation model, based on the linearized Navier–Stokes equations, is proposed. It includes th...

  • Article
  • Open Access
5 Citations
1,865 Views
10 Pages

Generation of Bright–Dark Pulse Pairs in the Er-Doped Mode-Locked Fiber Laser Based on Doped Fiber Saturable Absorber

  • Yaoyao Qi,
  • Qixing Yu,
  • Wei Sun,
  • Yaqing Gao,
  • Yu Zhang,
  • Zhenxu Bai,
  • Jie Ding,
  • Bingzheng Yan,
  • Yulei Wang and
  • Dapeng Yan
  • + 1 author

This study reports new types of passive mode-locked Er-doped fiber laser (EDFL) based on a segment of doped fiber saturable absorber (DFSA) with Tm/Ho-doped fiber (THDF), Yb-doped fiber (YDF), and Er-doped fiber (EDF). By employing THDF-SA, a bright...

  • Article
  • Open Access
1 Citations
2,332 Views
12 Pages

Sub-Nanosecond Passively Q-Switched Yellow and Orange Raman Lasers

  • Yu-Wen Ho,
  • Jian-Cheng Chen,
  • Yueh-Chi Tu,
  • Hsing-Chih Liang and
  • Yung-Fu Chen

6 February 2024

Sub-nanosecond high-peak-power passively Q-switched yellow and orange lasers are compactly developed using a near-concentric resonator with intracavity-stimulated Raman scattering (SRS) as well as second harmonic generation (SHG). The fundamental wav...

  • Article
  • Open Access
1 Citations
3,380 Views
11 Pages

Analysis of Scattering by Plasmonic Gratings of Circular Nanorods Using Lattice Sums Technique

  • Vakhtang Jandieri,
  • Kiyotoshi Yasumoto,
  • Jaromir Pistora and
  • Daniel Erni

11 September 2019

A self-contained formulation for analyzing electromagnetic scattering by a significant class of planar gratings composed of plasmonic nanorods, which were infinite length along their axes, is presented. The procedure for the lattice sums technique wa...

  • Article
  • Open Access
18 Citations
5,156 Views
14 Pages

A Laser-Based Multipass Absorption Sensor for Sub-ppm Detection of Methane, Acetylene and Ammonia

  • Wei Duan,
  • Fuwu Yan,
  • Yu Wang,
  • Hui Zhang,
  • Liuhao Ma,
  • Daxin Wen,
  • Wei Wang,
  • Gang Sheng and
  • Qiang Wang

12 January 2022

A compact, sensitive laser-based absorption sensor for multispecies monitoring of methane (CH4), acetylene (C2H2) and ammonia (NH3) was developed using a compact multipass gas cell. The gas cell is 8.8 cm long and has an effective optical path length...

  • Article
  • Open Access
11 Citations
3,684 Views
9 Pages

Manipulation Technique for Precise Transfer of Single Perovskite Nanoparticles

  • Filipp Komissarenko,
  • George Zograf,
  • Sergey Makarov,
  • Mikhail Petrov and
  • Ivan Mukhin

In this article, we present the pick-and-place technique for the manipulation of single nanoparticles on non-conductive substrates using a tungsten tip irradiated by a focused electron beam from a scanning electron microscope. The developed technique...

  • Article
  • Open Access
6 Citations
3,698 Views
12 Pages

Multimodal Nonlinear Microscopy for Therapy Monitoring of Cold Atmospheric Plasma Treatment

  • Tobias Meyer,
  • Hyeonsoo Bae,
  • Sybille Hasse,
  • Jörn Winter,
  • Thomas von Woedtke,
  • Michael Schmitt,
  • Klaus-Dieter Weltmann and
  • Juergen Popp

26 August 2019

Here we report on a non-linear spectroscopic method for visualization of cold atmospheric plasma (CAP)-induced changes in tissue for reaching a new quality level of CAP application in medicine via online monitoring of wound or cancer treatment. A com...

  • Article
  • Open Access
334 Views
20 Pages

Second Harmonic Generation Nanoparticles for Biomedical Imaging: Synthesis and Interaction with Model Bio-Interfaces

  • Irene Nepita,
  • Maria Teresa Buscaglia,
  • Belen Arcos-Álvarez,
  • Eduardo Guzmán,
  • Eva Santini,
  • Libero Liggieri and
  • Francesca Ravera

26 January 2026

This work investigates the synthesis and characterization of Barium Titanate (BT) nanoparticles, which exhibit non-linear optical properties, with a focus on their potential application in biomedical imaging. BT nanoparticles are active in second har...

  • Review
  • Open Access
8 Citations
3,679 Views
15 Pages

Coherent THz Hyper-Raman: Spectroscopy and Application in THz Detection

  • Arianna Ceraso,
  • Sen Mou,
  • Andrea Rubano and
  • Domenico Paparo

23 November 2019

Recently we have demonstrated a new nonlinear optical effect in the THz interval of frequencies. The latter is based on the use of femtosecond optical pulses and intense, sub-ps, broadband terahertz (THz) pulses to generate a THz-optical four- and fi...

  • Article
  • Open Access
7 Citations
5,391 Views
17 Pages

Measurement of the proton beam current (0.1–40 nA) at the medical treatment facility PROSCAN at the Paul Scherrer Institut (PSI) is performed with ionization chambers. To mitigate the scattering issues and to preserve the quality of the beam delivere...

  • Review
  • Open Access
2 Citations
2,141 Views
20 Pages

Continuous-Wave Self-Raman Vanadate Lasers Generating Versatile Visible Wavelengths

  • Di Li,
  • Chien-Yen Huang,
  • Xiu-Wei Chang,
  • Hsing-Chih Liang and
  • Yung-Fu Chen

In this review, the developments of efficient high-power CW orange-lime-green lasers by using intracavity stimulated Raman Scattering (SRS) in Nd-doped vanadate lasers are systematically discussed. The overall properties of the spontaneous Raman spec...

  • Feature Paper
  • Article
  • Open Access
25 Citations
6,212 Views
20 Pages

Characterizing Hypervelocity Impact (HVI)-Induced Pitting Damage Using Active Guided Ultrasonic Waves: From Linear to Nonlinear

  • Menglong Liu,
  • Kai Wang,
  • Cliff J. Lissenden,
  • Qiang Wang,
  • Qingming Zhang,
  • Renrong Long,
  • Zhongqing Su and
  • Fangsen Cui

18 May 2017

Hypervelocity impact (HVI), ubiquitous in low Earth orbit with an impacting velocity in excess of 1 km/s, poses an immense threat to the safety of orbiting spacecraft. Upon penetration of the outer shielding layer of a typical two-layer shielding sys...

  • Article
  • Open Access
55 Citations
10,194 Views
20 Pages

Detection and Discrimination of Non-Melanoma Skin Cancer by Multimodal Imaging

  • Sandro Heuke,
  • Nadine Vogler,
  • Tobias Meyer,
  • Denis Akimov,
  • Franziska Kluschke,
  • Hans-Joachim Röwert-Huber,
  • Jürgen Lademann,
  • Benjamin Dietzek and
  • Jürgen Popp

17 October 2013

Non-melanoma skin cancer (NMSC) belongs to the most frequent human neoplasms. Its exposed location facilitates a fast ambulant treatment. However, in the clinical practice far more lesions are removed than necessary, due to the lack of an efficient p...

  • Article
  • Open Access
11 Citations
4,654 Views
8 Pages

Second-Harmonic Generation in Suspended AlGaAs Waveguides: A Comparative Study

  • Iännis Roland,
  • Marco Ravaro,
  • Stéphan Suffit,
  • Pascal Filloux,
  • Aristide Lemaître,
  • Ivan Favero and
  • Giuseppe Leo

23 February 2020

Due to adjustable modal birefringence, suspended AlGaAs optical waveguides with submicron transverse sections can support phase-matched frequency mixing in the whole material transparency range, even close to the material bandgap, by tuning the width...

  • Article
  • Open Access
2 Citations
1,559 Views
23 Pages

Enhancing Hyperlocal Wavelength-Resolved Solar Irradiance Estimation Using Remote Sensing and Machine Learning

  • Vinu Sooriyaarachchi,
  • Lakitha O. H. Wijeratne,
  • John Waczak,
  • Rittik Patra,
  • David J. Lary and
  • Yichao Zhang

8 August 2025

Accurate characterization of surface solar irradiance at fine spatial, temporal, and spectral resolution is central to applications such as solar energy and environmental monitoring. On the one hand, modeling radiative transfer to achieve such accura...

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