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Insights into correlation between satellite infrared information and fault activities

Progress in Natural Science:Materials International 2006年第4期16卷 394-402页

作者： MA Jin, WANG Yipeng, CHEN Shunyun, LIU Peixun and LIU Liqiang State Key Laboratory of Earthquake Dynamics, Institute of Geology, China Earthquake Administration, Beijing 100029, China [a]State key Laboratory of Earthquake Dynamics Institute of Geology China Earthquake Administration Bejing China

Tectonic activities are accompanied with material movement and energy transfer, which definitely change the state of thermal radiation on the ground. Thus it is possible to infer present-day tectonic activities based on variations of the thermal radiation state on the ground. The received satellite infrared information is, however, likely influenced by many kinds of factors. Therefore, the first problem that needs to be solved is to extract information on tectonic activities and eliminate effects of external (non-tectonic) factors. In this study, we firstly make a review of the current studies on this subject, and then present the technical approach and our research goal. Using the data of 20 years from the infrared band of the satellite of National Oceanic and Atmospheric Administration (NOAA) and the method we have developed, we investigate fault activities in western China. The results show that the areas with high residual values of land surface brightness temperature (LSBT), which is presumably related to faultings in space, accord usually with the locations of followed major earthquakes. The times of their value growing are also roughly consistent with the beginning of active periods of earthquakes. The low frequency component fields of the LSBT, acquired from wavelet analysis, exhibit well the spatial distributions of active faults. The "heat penetrability index" (HPI) related with enhancement of subsurface thermal information has been expressed well for the backgrounds of accelerated tectonic motions, and some correlations exist between HPI and the local faulting and seismicity. This study provides a new approach to study temporal-spatial evolution of recent activities of faults and their interactions.

关键词： infrared emission fault activity residual of land surface brightness temperature heat penetrability index.

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infrared Measurements of Heating and Cooling emissions in Aluminium and Steel during Tensile and Cyclic Loading

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Journal of Materials Science & Technology 1990年第2期6卷 106-111页

作者：黄毅 G.E.Hicho R.J.Fields Institute of Metal Research Academia SinicaShenyang110015China National Bureau of Standards Institute for Materials Science and Engineering USA

In this paper,a new thermographic method based on the measurement of infrared emission(IR) from the surface of loaded body has been used to study the cooling and heating in aluminium and steel specimens under tensile and cyclic loading.A typical test procedure using infrared to measure thermographic changes near the crack tip and the immediate surrounding area is *** addi- tion,a procedure for determining the stress concen- tration near the crack tip is also *** are given for thermoelastic cooling phenomenon of metals during the tensile process and IR cooling and IR heating emissions at the crack tip during cyclic *** is drawn to the multiple phenomenon of IR cooling emission in the received signal as the applied load range increases beyond the elastic limit of both metals.A new application of the IR technique to the determination of the po- sition of crack tip during cyclic loading is also pres- ented.

关键词： thermoelastic effect stress concentration elastic-plastic deformation infrared emission

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Modulation of the cutoff wavelength in the spectra for solar selective absorbing coating based on high-entropy films

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International Journal of Minerals,Metallurgy and Materials 2020年第10期27卷 1371-1378页

作者： Ping Song Cong Wang Jie Ren Ying Sun Yong Zhang Angélique Bousquet Thierry Sauvage Eric Tomasella Center for Condensed Matter and Material Physics Beihang UniversityBeijing 100083China Key Laboratory for Microstructural Material Physics of Hebei Province School of ScienceYanshan UniversityQinhuangdao 066004China Beijing Advanced Innovation Center of Materials Genome Engineering State Key Laboratory for Advanced Metals and MaterialsUniversity of Science and Technology BeijingBeijing 100083China UniversitéClermont Auvergne Centre national de la recherche scientifique(CNRS)SIGMA ClermontInstitut de Chimie de Clermont-Ferrand(ICCF)Clermont-Ferrand F-63000France Extreme Conditions and Materials:High Temperature and Irradiation(CEMHTI-UPR 3079 CNRS Orléans F-45100France

This paper demonstrates an intrinsic modulation of the cutoff wavelength in the spectra for solar selective absorbing coating based on high-entropy ***(NiCuCrFeSi)N((NCCFS)N)films were deposited by a magnetron sputtering *** backscattering spectroscopy analysis confirms the uniform composition and good homogeneity of these high-entropy *** real and imaginary parts of the permittivity for the(NCCFS)N material are calculated on the basis of the reflectance spectral fitting results.A redshift cutoff wavelength of the reflectance spectrum with increasing nitrogen gas flow rate exists because of the different levels of dispersion when changing nitrogen *** realize significant solar absorption,the film surface was reconstituted to match its impedance with air by designing a pyramid nanostructure *** with the absorptance of the as-deposited films,the designed metasurface obtains a significant improvement in solar absorption with the absorptance increasing from 0.74 to *** metasurfaces also show low mid-infrared emissions with thermal emittance that can be as low as *** results demonstrate a new idea in the design of solar selective absorbing surface with controllable absorptance and low infrared emission for high-efficiency photo-thermal conversion.

关键词： cutoff wavelength solar selective absorption infrared emission nanostructure high-entropy film

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The dusty and extremely red progenitor of the typeⅡsupernova 2023ixf in Messier 101

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Science China(Physics,Mechanics & Astronomy) 2024年第1期67卷 160-172页

作者： Danfeng Xiang Jun Mo Lingzhi Wang Xiaofeng Wang Jujia Zhang Han Lin Lifan Wang Department of Physics Tsinghua UniversityBeijing 100084China South America Center for Astronomy National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China Beijing Planetarium Beijing Academy of Sciences and TechnologyBeijing 100044China Yunnan Observatories Chinese Academy of SciencesKunming 650216China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of SciencesKunming 650216China International Centre of Supernovae Yunnan Key LaboratoryKunming 650216China Mitchell Institute for Fundamental Physics and Astronomy Texas A&M UniversityCollege StationTX 77843USA

Stars with initial masses in the range of 8-25 solar masses are thought to end their lives as hydrogen-rich supernovae(SNeⅡ).Based on the pre-explosion images of Hubble space telescope(HST)and Spitzer space telescope,we place tight constraints on the progenitor candidate of type IIP SN 2023ixf in Messier *** of the spectral energy distribution(SED)of its progenitor with dusty stellar spectral models results in an estimation of the effective temperature as 3091+*** luminosity is estimated as lg(L/L⊙)~4.83,consistent with a red supergiant(RSG)star with an initial mass of 12-1+2M⊙.The derived mass loss rate(6×10^(-6)-9×10^(-6)M⊙yr^(-1))is much lower than that inferred from the flash spectroscopy of the SN,suggesting that the progenitor experienced a sudden increase in mass loss when approaching the final *** the infrared bands,significant deviation from the range of regular RSGs in the color-magnitude diagram and period-luminosity space of the progenitor star indicates enhanced mass loss and dust *** with new evidence of polarization at the early phases of SN 2023ixf,such a violent mass loss is likely a result of binary interaction.

关键词： stellar evolution mass loss red supergiants infrared emission supernovae

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Multi-photon quantum cutting in Gd_(2)O_(2)S:Tm^(3+) to enhance the photo-response of solar cells

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Light(Science & Applications) 2015年第1期4卷 144-151页

作者： De-Chao Yu Rosa Martin-Rodriguez Qin-Yuan Zhang Andries Meijerink Freddy T Rabouw State Key Laboratory of Luminescence Materials and Devices and Institute of Optical Communication Materials South China University of TechnologyGuangzhou 510641China Debye Institute for Nanomaterials Science Utrecht UniversityP.O.Box 800003508 TA Utrechtthe Netherlands

Conventional photoluminescence(PL)yields at most one emitted photon for each absorption ***(or quantum cutting)materials can yield more than one photon by virtue of energy transfer processes between luminescent *** this work,we introduce Gd2O2S:Tm^(3+) as a multi-photon quantum *** can convert near-infrared,visible,or ultraviolet photons into two,three,or four infrared photons of,1800 nm,*** cross-relaxation steps between Tm^(3+) ions that lead to quantum cutting are identified from(time-resolved)PL as a function of the Tm^(3+) concentration in the crystal.A model is presented that reproduces the way in which the Tm^(3+) concentration affects both the relative intensities of the various emission lines and the excited state dynamics and providing insight in the quantum cutting ***,we discuss the potential application of Gd2O2S:Tm^(3+) for spectral conversion to improve the efficiency of next-generation photovoltaics.

关键词： downconversion infrared emission quantum cutting solar cells spectral conversions

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Photonic properties of novel Yb3＋ doped germanium-lead oxyfluoride glass-ceramics for laser cooling applications

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Frontiers of Optoelectronics 2018年第2期11卷 189-198页

作者： Lauro J. Q. MAIA Jyothis THOMAS Yannick LEDEMI Kummara V. KRISHNAIAH Denis SELETSKIY Younes MESSADDEQ Raman KASHYAP Instituto de Fisica Universidade Federal de Goias Av. Esperanga 1533 Campus Samambaia Goiania GO 74690-900 Brazil Department of Electrical Engineering Ecole Polytechnique de Montrral P.O. Box 6079 Station Centre-ville Montreal QC H3C 3A7 Canada Department of Engineering Physics Ecole Polytechnique de Montrral P.O. Box 6079 Station Centre-ville Montreal QC H3C 3A7 Canada Centre d'Optique Photonique et Laser 2375 Rue de la Terrasse Universite Laval Qurbec QC G1V 0A6 Canada

Abstract In recent years, our research group has developed and studied new rare-earth doped materials for the promising technology of solid-state laser cooling, which is based on anti-stokes fluorescence. To the best of our knowledge, our group is the only one in Canada leading the research into the properties of nanoparticles, glasses and glass-ceramics for optical refrigeration appli- cations. In the present work, optical properties of 50GeO2- 30PbF2-18PbO-2YbF3 glass-ceramics for laser cooling are presented and discussed as a function of crystallization temperature. Spectroscopic results show that samples have near infrared photoluminescence emission due to the 2F5/2 - 2F7/2 Yb3＋ transition, centered at -1016 nm with an excitation wavelength of 920 nm or 1011 nm, and the highest photoluminescence emission efficiency occurs for heat-treatment for 5 h at 350℃. The internal photolumi- nescence quantum yield varies between 99% and 80%, depending on the temperature of heat-treatment, being the most efficient under 1011 nm excitation. The 2F5/2 lifetime increases from 1.472 to 1.970 ms for heat treatments at 330℃ to 350℃, respectively, due to energy trapping and the low phonon energy of the nanocrystals. The sample temperature dependence was measured with a fiber Bragg grating sensor, as a function of input pump laser wavelength and processing temperature. These measure- ments show that the heating process approaches near zero for an excitation wavelength between 1020 and 1030 nm, which is an indication that phonons are removed effectivelly from the glass-ceramic materials, and they can be used for optical laser cooling applications. On theother hand, the temperature increase as a function of input laser power into samples remains constant between 920 and 980 nm wavelength excitation, a temperature variation of 36 K/W （temperature of 58℃/W） was attained under excitation at 950 nm, showing a possible use for biomedical applications to be explored.

关键词： optical refrigeration oxyfluoride glass-cera-mics Yb3+ doping quantum yield infrared emission lifetime

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Global Warming and Its Multiple Causes

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Journal of Atmospheric Science Research 2020年第2期3卷 28-31页

作者： Romdhane Ben Slama Higher Institute of Applied Sciences and Technology of Gabes(ISSAT) University of GabesTunisia

The global warming which preoccupies humanity,is still considered to be linked to a single cause which is the emission of greenhouse gases,CO2 in *** this article,we try to show that,on the one hand,the greenhouse effect(the radiative imprisonment to use the scientific term)took place in conjunction with the infrared radiation emitted by the *** surplus of CO2 due to the combustion of fossil fuels,but also the surplus of infrared emissions from artificialized soils contribute together or each separately,to the imbalance of the natural greenhouse effect and the trend of global *** addition,another actor acting directly and instantaneously on the warming of the ambient air is the heat released by fossil fuels estimated at 17415.1010 kWh/year inducing a rise in temperature of 0.122°C,or 12.2°C/century.

关键词： Greenhouse effect gases Global warming infrared emission Heat of combustion

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Investigation on Open-Circuit Voltage of an Efficiency-Boosting Solar Cell Technique Featuring V-Configuration

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Natural Resources 2021年第12期12卷 383-389页

作者： Jianming Li Institute of Semiconductors Chinese Academy of Sciences Beijing China

The V-Shaped Module (VSM) solar cell technology, which breaks the traditional concept of solar cell system, has been proven to enhance power conversion efficiency of some solar cells and has offered opportunities to increase generation power densities in area-limited applications. Compared to a planar cell system, the VSM has an additional opportunity to absorb photons and taps the potential of solar cells. In this study, the VSM, the proposed common technique enhancing efficiencies of various solar cells, was investigated by using commercially available multi-crystalline silicon solar cells. The VSM technique enables the efficiencies of the multi-crystalline silicon cells to increase from 13.4% to 20.2%, giving an efficiency boost of 51%. Though the efficiency of the cells increases, the open-circuit voltage of the cells decreases owing to the VSM technique. Furthermore, the obvious reduction in open-circuit voltage in the VSM was found and the phenomenon is explained for the first time.

关键词： Solar Cells Multicrystalline Silicon Light Trapping infrared emission

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Structural and Optical Performance of GaN Thick Film Grown by HVPE

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Journal of Semiconductors 2007年第1期28卷 19-23页

作者：魏同波马平段瑞飞王军喜李晋闽刘喆林郭强曾一平中国科学院半导体研究所北京100083

Thick GaN films were grown on GaN/sapphire template in a vertical HVPE reactor. Various material characterization techniques,including AFM, SEM, XRD, RBS/Channeling, CL, PL, and XPS, were used to characterize these GaN epitaxial films. It was found that stepped/terraced structures appeared on the film surface,which were indicative of a nearly step-flow mode of growth for the HVPE GaN despite the high growth rate. A few hexagonal pits appeared on the surface, which have strong light emission. After being etched in molten KOH, the wavy steps disappeared and hexagonal pits with {1010} facets appeared on the surface. An EPD of only 8 ×10^6cm^-2 shows that the GaN film has few dislocations. Both XRD and RBS channeling indicate the high quality of the GaN thick films. Sharp band-edge emission with a full width at half maximum（FWHM）of 67meV was observed, while the yellow and infrared emissions were also found. These emissions are likely caused by native defects and C and O impurities.

关键词： GaN HVPE CL RBS/channeling yellow emission infrared emission

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