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This PDF file contains the front matter associated with SPIE Proceedings Volume 10765, including the Title Page, Copyright information, Table of Contents, Author and Conference Committee lists.
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Details of a multispectral imaging radiometer specially designed to retrieve fire characteristics from a nanosatellite platform are presented. The instrument consists of an assembly of three cameras providing co-registered midwave infrared, longwave infrared, and visible image data. Preliminary evaluation of the instrument budgets showed approximately a mass of 12 kg, an envelope of 220×240×200 mm3, and an average power consumption of 13 W. A method was devised to stagger two linear arrays of 512×3 VOx microbolometers in each infrared detector assembly. Investigation of the first completed detector assemblies showed an alignment accuracy better than 10% of pixel pitch and a response uniformity achieved across 92% of the pixels. Effects of the thermal environment seen by the pixels were evaluated to optimize the radiometric packaging design. It was found that the resulting thermal stability of the arrays, combined with the available electronic dynamic range, allows acquisition of targets with temperatures as high as 750 K with the desired accuracy and without saturation. The detector assemblies were able to withstand extreme environments with vibration up to 14 grms and temperatures from 218 to 333 K. Exposing the assembly’s window and bandpass filter to proton and Co-60 gamma radiation with successive dose of 10 krad and 100 Gy resulted in no adverse effect on their transmittance characteristics. Performance characteristics of the assembled midwave and longwave infrared telescopes were consistent with modeling predictions. Results of the point spread function measurement supported the conclusion that the lenses alignment had been achieved within mechanical tolerances for both telescopes.
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Although the effects on imaging through natural fog have been well studied, the literature does not yield clear answers as to the conditions when infrared outperforms visible band imaging. While theoretical study of scattering properties are useful, they have consistently lacked the connection to the intrinsic thermal contrast available in outdoor scenes in foggy conditions—the low thermal contrast during heavy fog is responsible for the disappointing performance for thermal imaging through fog in practice. We demonstrate experiments showing that thermal infrared performs well for artificial fog, and that the artificial fogs closely replicate the optical properties of natural fogs of the same diameter, but that the particle sizes of artificial fogs are too small to simulate natural fog particles. This discrepancy makes infrared imaging look much better than it otherwise would when using
artificial fogs to simulate natural ones.
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Based on the development and application needs, Professor Siwen Bi has proposed quantum remote sensing (QRS) in the early 2001. Firstly, the paper introduces the background, concept and research status at home and abroad of quantum remote sensing, it also introduces the differences and advantages of quantum remote sensing compared with the classical remote sensing. Then it elaborates wave-particle duality, Superposition State, Tunneling Effect of QRS research basis and quantum entanglement, its basic theory and information mechanism, as well as the research progress of QRS imaging processing, quantum spectrum remote sensing and QRS calibration. Besides, it emphasizes the experimental process of QRS imaging and the production of principle prototype, based on which, Professor Bi proposed active imaging information transmission technology of satellite borne QRS technical solutions and conducted research on its system composition and working principle, squeezing light preparation of active imaging, injection device and quantum non-noise amplifier device, providing solutions and technical basis for realizing active imaging technology of satellite-borne QRS. The QRS imaging technology can significantly improve the signal-to-noise ratio and space resolution of QRS imaging information transmission. Finally, the paper summarizes the research conditions over the past eighteen years and plan for the future.
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Based on the basic theory, information mechanism and imaging experiment of quantum remote sensing, quantum spectral imaging and quantum detection and identification, as well as the production of principle prototype, the author conducted researches on high-sensitivity target detection of infrared optical quantum squeezing that can breakthrough quantum noise limit, high resolution imaging technical solutions and imaging principle experiment, focusing on realizing of high sensitivity long-range target detection, system composition and working principle of high-resolution imaging experimental device, infrared quantum optical squeezed light preparation and injection, and quantum noiseless amplifier, aiming to resolve relevant crucial problems, which provide technical basis for the production of engineering prototype and its experimental device. Besides, based on the project assignment, the paper firstly introduces research status at home and abroad, the development tendency, and research significance and necessity, then it emphasizes the research target, research content and key technical index, as well as the overall technical solutions, solutions and feasibility analysis for key technologies. Finally, it summarizes benefit analysis, project arrangement and outcome forms.
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Long distance precise frequency and accurate time transfer methods based on optical fiber links have evolved rapidly in recent years, demonstrating excellent performance. They are attractive both for very high-performance applications and as a secure alternative complement to radio- and satellite-based methods. In this paper, we present development of infrastructure for such transmission containing 700+km of transmission lines, with planned cross border optical frequency connectivity. According to our knowledge, this will be the third such line globally. The infrastructure also shares fibers with existing data transmissions, both amplitude and phase modulated, which poses high demands on mutual isolation and insensitivity to cross talks.
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Small bodies like asteroids and comets are little differentiated objects that have preserved information about the early state of our solar system. Depending on the heliocentric distance of their origin and their further development they exhibit different pristine compositions that include minerals, ices, and refractory organics. Thus, the composition analysis of minor bodies enables investigations of their evolutionary paths and insights into early processes of planetary formation. In the last decades, new spaceflight and instrument technologies enabled detailed investigations of such bodies during flybys, orbital observations, in situ studies with descent probes, and lander experiments. Core payload elements of these missions include VIS to IR spectrometers, which provided regional and global maps of surface composition, texture, and temperature. The wide range of materials to be detected and the large variability of measurement conditions require dedicated instrumentation and observation strategies for this purpose. This paper reviews the state of the art knowledge and technology achievements in this research field. Scientific results, requirements, and instrumental solutions for minor planetary body studies with VIS to IR spectrometers and radiometers are discussed using examples like the Rosetta mission to comet 67P/Churyumov-Gerasimenko, the asteroid missions Dawn to 4 Vesta and 1 Ceres (dwarf planet), and Hayabusa2 to 162173 Ryugu. Based on our present knowledge, open questions in minor body research are summarized, and resulting scientific and instrumental requirements for future spaceborne VIS/IR spectral studies are elaborated in detail.
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TROTIS (TROjan asteroid Thermal Infrared multi-Spectral imager) is a high spatial-resolution thermal imaging system optimized for targets in the outer solar system with heritage from the Miniaturized Asteroid thermal infrared Imager and Radiometer (MAIR) for the AIDA mission as well as Bepi-Colombo mission's MErcury Radiometer and Thermal Infrared Spectrometer (MERTIS). TROTIS will provide unique science observations that will foster our understanding of Trojan asteroids. It will provide compositional information, thermal physical properties as well as help determine accurate shapes. In addition TROTIS can aid optical navigation, as it will be able to detect targets from any phase angle.
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The Planetary Spectroscopy Laboratory (PSL) of DLR in Berlin provides spectral measurements of primarily planetary analogues from the visible to the far-infrared range. PSL has supported the data analysis as well as the development and calibration of instruments for planetary missions from ESA, NASA and JAXA. For this purposes PSL provides reflection, transmission and emission spectroscopy of target materials. Currently PSL operates two identical Bruker Vertex 80V vacuum FTIR spectrometer, one spectrometer is equipped with aluminum mirrors optimized for the UV, visible and near-IR, the second features gold-coated mirrors for the near to far IR spectral range. External simulation chambers are attached to each of the instruments for emissivity measurements. The chamber at the near to far IR instruments allows emissivity measurements from 0.7-200 μm under vacuum for sample temperatures from 320K to above 900K, using an innovative induction system. The second chamber (purged with dry air and water cooled to ≤270K) allows emissivity measurements of samples with surface temperature from 290 to 420K. We measure bi-directional reflectance of samples, with variable incidence and emission angles between 13° and 85°. Samples are measured currently at room temperature and 170K, with a planned extension for temperatures below 100K. Bi-directional and hemispherical reflectance is measured under purging/vacuum conditions, covering the 0.2 to above 200 μm spectral range. Transmission of thin slabs, optical filters, optical windows, pellets, and others is measured in the complete spectral range from UV to FIR using a parallel beam configuration to avoid refraction.
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Rotationally shearing interferometer has been proposed for the detection of a faint planet next to a bright star. The instrument was successfully used in a laboratory for optical testing of novel optical components. It has also been used to test for presence of a planet in a laboratory-simulated solar system. The system may be used for detection of other, distant, invisible, unknown, and small sources next to the bright source.
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Joern Helbert, Darby Dyar, Ingo Walter, Dennis Wendler, Thomas Widemann, Emmanuel Marcq, Gabriel Guignan, Sabrina Ferrari, Alessandro Maturilli, et al.
The Venus Emissivity Mapper is the first flight instrument designed with a focus on mapping the surface of Venus using atmospheric windows around 1 μm. After several years of development VEM has a mature design with an existing laboratory prototype verifying an achievable instrument SNR of well above 1000 as well as a predicted error in the retrieval of relative emissivity of better than 1%. With that it will provide a global map of surface composition as well as redox state of the surface by observing the surface with six narrow band filters, ranging from 0.86 to 1.18 μm. Continuous observation of Venus' thermal emission will place tight constraints on current day volcanic activity. Eight additional channels provide measurements of atmospheric water vapor abundance as well as cloud microphysics and dynamics and permit accurate correction of atmospheric interference on the surface data. A mission combining VEM with a high-resolution radar mapper such as the ESA EnVision or NASA VERITAS mission proposals will provide key insights in the divergent evolution of Venus.
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Atmospheric Chemistry Suite (ACS) is a part of Russian contribution to ExoMars Trace Gas Orbiter (TGO) ESA-Roscosmos mission. ACS includes three separate infrared spectrometers (MIR, NIR and TIRVIM) with a different spectral coverage and targeted to the different science goals. ACS TIRVIM is a Fourier-transform spectrometer based on 2-inch double pendulum interferometer. It operates in the spectral range of 1.7-7 μm with the best spectral resolution 0.13 cm-1 for solar occultation (SO) mode and 0.8 cm-1 for nadir mode. In nadir mode TIRVIM is purposed to thermal sounding of the Martian atmosphere and aerosol properties retrieval. In SO mode TIRVIM is dedicated to trace gases measurements complementing to ACS MIR. After successful launch of ExoMars TGO on 16 April 2016 there were three time slots for turning on science instruments during cruise phase to execute necessary checks and calibration measurements. In March 2018 the nominal science orbit was reached after cruise and aerobraking phases. The first results of TIRVIM data processing show high performance of the instrument.
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The MErcury Radiometer and Thermal infrared Imaging Spectrometer (MERTIS) is a highly integrated instrument to study mineralogy and temperature distribution of Mercury’s surface in unprecedented quality. MERTIS was proposed in 2003 as payload of the Mercury Planetary Orbiter spacecraft of the joint ESA-JAXA BepiColombo mission. With the planned launch on top of an Ariane 5 in October of 2018, the mission will soon start its 7 years journey to Mercury. On its way to Mercury, BepiColombo will have 2 flybys of Venus and one of the Earth-Moon system. MERTIS will obtain data during each of these flybys – for Venus the first mid-infrared spectral data since Venera 15 in 1983. After arrival at Mercury in 2025 MERTIS will globally map the surface composition with a resolution of 500m, and study surface temperature variations providing an insight into the thermo-physical properties of the surface. To achieve this, MERTIS combines a push-broom IR grating spectrometer (TIS) with a radiometer (TIR) sharing the same optics, instrument electronics and in-flight calibration components for the whole wavelength range of 7-14 μm (TIS) and 7-40 μm (TIR), respectively. Instrument operations in the challenging environment at Mercury with power and data constraints require a sophisticated mapping scheme for the TIS observations, which also has to account for the MERTIS calibration needs. Execution of this scheme creates challenges for the operation of the instruments, data processing, and the creation of map products. Extensive onground testing and rehearsals during the Venus and Earth flybys will ensure flawless performance at Mercury.
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The MErcury Radiometer and Thermal Infrared Imaging Spectrometer (MERTIS) is an instrument to study mineralogy and temperature distribution of Mercury surface in unprecedented quality. MERTIS was proposed in 2003 as payload of the Mercury Planetary Orbiter spacecraft of ESA-JAXA BepiColombo mission and will reach Mercury in 2026. MERTIS will map the whole surface at 500m resolution combining a push-broom IR grating spectrometer (TIS) with a radiometer (TIR) sharing the same optics, instrument electronics and in-flight calibration components for the whole wavelength range of 7-14μm (TIS) and 7-40μm (TIR). Currently we are developing and testing an ingestion, calibration and transformation pipeline for MERTIS data, from raw telemetry level data to calibrated product and high level derived product. Bepicolombo Science Ground Segment (BC-SGS or SGS) is embracing new technologies for the BepiColombo mission and follows the latest NASA/PDS format, the xml based PDS4. We adopt open source languages and well optimized libraries for the underlying processing. The data processing pipeline is fully containerized via Docker to be independent from transition between server/OSs/environment, drastically reducing the integration and testing time. Due to strict infrastructural constrains like spacecraft downlink bandwidth and onboard mass memory, the already complex observation scenario is subject to further optimizations. This complicates the reconstruction process for higher-level products like global maps of emissivity and thermal inertia.
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We report design of laboratory prototype for a compact infrared acousto-optic imaging spectro-polarimeter, which may be implemented for remote or close-up analysis of planetary surfaces. The prototype concept contains a telecentric optics, apochromatic design over the bandwidth of 0.9–3.4 μm, and simultaneous imaging of two orthogonal linear polarizations of the same scene at a focal plane array (FPA). Two acousto-optic channels, the near-IR (0.9-1.7 μm) the mid-IR (1.5–3.4 μm), were developed with spectral resolution of 100 cm-1 (10 nm at 1 μm) and 25 cm-1 (20 nm at 3 μm) respectively. When imaging samples, the spatial resolution of 0.2 mm at the target distance of one meter was reached. It corresponds to 100 by 100 elements resolved at the FPA for each of the two light polarizations. This type of instruments may be considered as a potential reconnaissance and analysis tool for future planetary or moon landers and rovers to study spectral and polarization properties of the regolith.
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Enabling Technologies, Simulations, and Data Processing
The Airborne Infrared Spectrometer (AIR-Spec) took measurements of five infrared coronal emission lines from on board a NSF/NCAR airplane during the solar eclipse in August 2017. An open-loop image stabilization system was implemented using a gyroscope and fast steering mirror; 90% of the 60 millisecond exposures had an RMS jitter below 4.6 arcseconds. To increase the exposure time to 1 second, a closed-loop system is proposed using a proportional-integral-derivative (PID) controller and an image cross-correlation algorithm. We predict that 100% of 1 second exposures will have an RMS jitter below 4.6 arcseconds. A detailed analysis of the proposed closed-loop stabilization system is presented.
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Research of modeling infrared radiation characteristic of ocean background plays an important role in areas like marine remote sensing, prevention and control of ocean pollution, meteorological observation, and so on. In this paper, we build a three-D ocean surface model based on P-M wave spectrum, then set up the camera projection model. We use LOWTRAN 7 to calculate solar irradiance and sky background radiance, and then use thermal radiation theory to calculate the thermal radiation of the ocean itself and use bidirectional reflectance distribution function to calculate the reflection of the sea to the solar radiation and sky background radiance. Finally, with all the above radiation components considered, we generate the ocean background infrared simulation image.
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Photographs of the lights seen from outer space at night are a valuable source of freely available online information of city light distribution. Here we take advantage of recently available imagery from the International Space Station (ISS), which provides night-time high resolution images of most cities at Earth. We perform a multifractal analysis of night lights patterns of some of the largest and most populous cities in the World, searching for valuable information of city light spatial distribution. We calculate the fractal dimension, multifractal spectral width, and multifractal spectral range. Then we correlate these fractal parameters with three city characteristics: light pollution, crime index, and quality of life index. And we find a clear relationship between multifractality and the index of quality of life.
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We present a polarization sensitive measurement focused on retrieve elliptical phase retardation properties. The system is based on rotating two linear polarizers. And a demodulation algorithm is proposed to retrieve a partial matrix of Muller from the intensity output signal. The polarimetry setup also employs a monochrome camera as detection system and a HeNe laser as light source. Simulation and experimental results in transparent samples are presented showing the feasibility of the measurement and the potential usage in a multiwavelength arrangement.
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After several changes over the past two years, mid-Infra Red (IR) spectral band 3-4µm has been decided to use for LAPAN's IR camera module. Moreover, the IR camera only will equip with one microbolometer as the detector. The peat fire and Indonesia's volcano activities are two major missions of this experimental IR camera.
Applying the generally used design process including the trade-off, the LAPAN's IR camera module has been made. Optical analysis as the initial step has been laid a solid foundation for subsequent process. A commercial process, in this cases Zemax, plays an important role during this design process. Meanwhile, mechanical design, the second step of designing, includes the structure / thermal analysis as well. Structure/Thermal analysis basically is to ascertain whether the LAPAN's IR camera module meets all the performance or not when operating in harsh condition. Once again, the commercial software, Thermal Desktop/Sinda Fluint, and Solidworks have been utilized for the analysis and design process. Electrical design as the last procedure is the least process done due to limited time.
The spot diagram, encircled energy, and MTF graph shows that design of our refractive lens including the selected material meet the performance requirement. The natural frequencies as the mechanical analysis result indicate that our mechanical design is on the track. Meanwhile, for structure/thermal problem, the analysis tells the LAPAN's IR camera module will work well in space environment as well. Furthermore, the electrical design provides a good enough interface between the FPA detector and the electronics
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We will review the previous results following the investigation of efficient generation of monochromatic, high-peak power, and tunable THz waves based on nonlinear frequency down-conversion. We are going to compare this approach with all the other competing approaches and illustrate advantages of this approach for realizing certain applications. We shall brainstorm the further development of the field.
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Following the goals of single-chip integrated dual comb spectrometers, we report on recent results on mid-infrared frequency combs. We demonstrate frequency comb operation with a bi-functional quantum cascade material, which allows the integration of lasers and detectors on one chip. With this device, we hold the power and efficiency record of QCL frequency combs. In the second part, we will present first evidence of frequency comb generation using mode-locked interband cascade lasers. With the demonstration of picosecond pulse generation in the mid-infrared, we open a new path towards battery driven sensitive high-resolution spectrometers miniaturized to chip-scale dimensions.
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Interband cascade lasers (ICLs) are efficient mid-infrared (MIR) semiconductor light sources based typically on InAs and GaInSb materials forming a broken gap system and hence type II quantum wells (QWs) being the active part in this kind of emitters. There has already been achieved a significant progress in the performance of ICLs, driven mainly by the gas sensing applications and originating from their unique operational characteristics when especially compared to quantum cascade lasers. However, there are still growing demands with respect to laser sources in the MIR and new areas of applications evolve, all of which stimulate the efforts to improve the performance of such devices and to search for completely new solutions which could offer properties hardly reachable with existing structures. Here, by using k·p theory employing strain and band structure engineering of various In(As,Sb) and (Ga,In)(As,Sb) type II materials’ combinations there will be considered several novel designs of the active region of ICLs. These calculations show that such new features can be obtained as fully strain-free ICL devices, significant extension of the emission spectral range, polarization independent gain in the MIR or enhanced sensitivity of radiative processes rates to external electric field to be exploited in bias-controlled mode-locked ICLs. The respective type II QW designs are proposed and discussed.
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Molecule and gas sensing is a key technology that is applied in multiple environmental, industrial and medical fields. In particular optical detection technologies enable contactless, nondestructive, highly sensitive and fast detection of even smallest concentrations of trace gases and molecules. During the past years, an increasing demand for mid-infrared (MIR) light sources suitable for, e.g. molecule or gas sensing applications, has driven the development and optimization of novel MIR lasers and light sources, such as quantum cascade lasers (QCL) or interband cascade lasers (ICL). Despite the progress on MIR light sources, there is still a lack in appropriate MIR detectors. Here, we present and discuss two promising and novel GaSb/InAs-based detector concepts. First, resonant tunneling diode (RTD) photodetectors as an alternative to avalanche photodetectors. In RTDs, amplification of photogenerated minority charge carriers is based on modulation of a majority charge carrier resonant tunneling current. Second, interband cascade photodetectors (ICD), in which a cascading scheme allows for fast carrier extraction and a compensation of the diffusion length limitation.
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We review the direct and indirect methods used for the detection of a planet outside our solar system. We compare the popular methods, emphasizing their attractiveness and exceptional features. The principal indirect planetdetection techniques are gravitational micro-lensing, transit intensity fluctuations, and spectroscopic radial velocity. Most of the research on the exo-solar planet detection within the last 20 years has been performed in conjunction with the star surveys. The direct methods include imaging, image reconstruction, astrometry, interferometry, nulling interferometry, rotational shearing interferometry, phase closure, and coronagraphy. Many of the imaging techniques involve the ground telescopes that are breaking the conventional rules of resolution, and ground-based interferometers. We observe that planet detection leads to novel concepts in the imaging science.
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A laser shock wave is a pressure wave in a gigapascal range propagating at speeds above the speed of sound in a medium, induced by a high-power density laser pulse. Its duration is of the order of magnitude of nanoseconds. When the shock wave propagates in a solid, some materials characteristics in the area where laser beam is incident, change due to the application of compressive residual stress. These may be hardness, corrosion resistance, stress-fatigue resistance, to name a few. The shock wave has been found useful for working materials in diverse application fields such as aeronautics, defense, material science, and micro-components. The shock wave pressure decreases drastically as it propagates inside the solid, making it difficult to obtain experimental data when the shock wave propagates in solids with a thickness greater than one millimeter. We employ finite element method for the solution of shock wave propagation problems. Its primary benefit is that wave pressure and velocity may be determined upon modeling for thicknesses greater than one millimeter. We demonstrate a non-linear relationship between the material thickness and the shock wave that decreases with increasing slab thickness. In addition, the relationship between thickness and shock wave velocity is found. We estimate the material thickness by obtaining the attenuation ratio of the shock wave pressure.
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Study of vegetation by non-invasive methods is a relevant topic for the preservation of the forests, by mean the biochemical analysis of vegetation, the study of the plants and analysis of their behavior with external agents. These methods are based on the spectral signatures of leaves under different behavior conditions. This information can be used in remote sensing techniques for various application through the use of multispectral images or measurements of spectroradiometers. In this document, we examine the diffuse reflectance spectra of the leaves of tree species in two spectral ranges. The first region is enclosed from 0.4 μm to 2.5 μm which corresponds to the solar radiation. The second region covers from 2.5 μm to 20 μm. The study explains the change in the specific signatures of the leaves in relation to the internal decomposition of the foliar plate, due to dehydration of the leaf, the loss of chlorophyll, the production of anthocyanin, and the destruction of the cellular structure, considering two senescent states.
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