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Extraction of the key infrared radiation temperature features concerning stress and crack evolution of loaded rocks
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作者 Wei Liu Liqiang Ma +4 位作者 Michel Jaboyedoff Marc-Henri Derron Qiangqiang Gao Fengchang Bu Hai Sun 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第8期1059-1081,共23页
The infrared radiation temperature(IRT)variation concerning stress and crack evolution of rocks is a critical focus in rock mechanics domain and engineering disaster warning.In this paper,a methodology to extract the ... The infrared radiation temperature(IRT)variation concerning stress and crack evolution of rocks is a critical focus in rock mechanics domain and engineering disaster warning.In this paper,a methodology to extract the key IRT features related to stress and crack evolution of loaded rocks is proposed.Specifically,the wavelet denoising and reconstruction in thermal image sequence(WDRTIS)method is employed to eliminate temporal noise in thermal image sequences.Subsequently,the adaptive partition temperature drift correction(APTDC)method is introduced to alleviate temperature drift.On this basis,the spatial noise correction method based on threshold segmentation and adaptive median filtering(OTSU-AMF)is proposed to extract the key IRT features associated with microcracks of loaded rocks.Following temperature drift correction,IRT provides an estimation of the thermoelastic factor in rocks,typically around 5.29×10^(-5) MPa^(-1) for sandstones.Results reveal that the high-temperature concentrated region in cumulative thermal images of crack evolution(TICE)can elucidate the spatiotemporal evolution of localized damage.Additionally,heat dissipation of crack evolution(HDCE)acquired from TICE quantifies the progressive failure process of rocks.The proposed methodology enhances the reliability of IRT monitoring results and provides an innovative approach for conducting research in rock mechanics and monitoring engineering disasters. 展开更多
关键词 infrared radiation(ir) Temperature drift Spatial background noise Rock fracture Average infrared radiation temperature(AirT) Heat dissipation of crack evolution(HDCE)
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Failure mechanism and infrared radiation characteristic of hard siltstone induced by stratification effect
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作者 CHENG Yun SONG Zhanping +2 位作者 XU Zhiwei YANG Tengtian TIAN Xiaoxu 《Journal of Mountain Science》 SCIE CSCD 2024年第3期1058-1074,共17页
The deformation in sedimentary rock induced by train loads has potential threat to the safe operation of tunnels. This study investigated the influence of stratification structure on the infrared radiation and tempora... The deformation in sedimentary rock induced by train loads has potential threat to the safe operation of tunnels. This study investigated the influence of stratification structure on the infrared radiation and temporal damage mechanism of hard siltstone. The uniaxial compression tests, coupled with acoustic emission(AE) and infrared radiation temperature(IRT) were conducted on siltstones with different stratification effects. The results revealed that the stratigraphic structure significantly affects the stress-strain response and strength degradation characteristics. The mechanical parameters exhibit anisotropy characteristics, and the stratification effect exhibits a negative correlation with the cracking stress and peak stress. The failure modes caused by the stratification effect show remarkable anisotropic features, including splitting failure(Ⅰ: 0°-22.50°, Ⅱ: 90°), composite failure(45°), and shearing failure(67.50°). The AE temporal sequences demonstrate a stepwise response characteristic to the loading stress level. The AE intensity indicates that the stress sensitivity of shearing failure and composite failure is generally greater than that of splitting failure. The IRT field has spatiotemporal migration and progressive dissimilation with stress loading and its dissimilation degree increases under higher stress levels. The stronger the stratification effect, the greater the dissimilation degree of the IRT field. The abnormal characteristic points of average infrared radiation temperature(AIRT) variance at local stress drop and peak stress can be used as early and late precursors to identify fracture instability. Theoretical analysis shows that the competitive relationship between compaction strengthening and fracturing damage intensifies the dissimilation of the infrared thermal field for an increasing stress level. The present study provides a theoretical reference for disaster warnings in hard sedimentary rock mass. 展开更多
关键词 Hard siltstone Failure mechanism Stratification effect infrared radiation characteristic Temporal-damage mechanism DISSIMILATION
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The Influence of Heat Source IR Radiation on Black-Body Heating/Cooling with Increased CO2 Concentration
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作者 Thorstein O. Seim Borgar T. Olsen 《Atmospheric and Climate Sciences》 CAS 2023年第2期240-254,共15页
This study deal with interactions between thermal and radiative energy flow in experimental situations of varying complexity. Of special interest is how IR energy, re-emitted from CO<sub>2</sub> gas, behav... This study deal with interactions between thermal and radiative energy flow in experimental situations of varying complexity. Of special interest is how IR energy, re-emitted from CO<sub>2</sub> gas, behaves in an earth/atmosphere simulated setup. Such an experiment was performed by Hermann Harde and Michael Schnell where they show that IR radiation emitted from CO<sub>2</sub> can warm a small black-body metal plate. In a control experiment, we verified this result. However, in their experiment, the amount of IR radiation from the heating element was strongly attenuated. In a modified experiment, where IR emission from the heating source is present, no heating but a slight cooling of a black object is found when air is replaced by CO<sub>2</sub>. The modified experimental situation is also more like the earth/atmosphere situation. The presence of IR radiation from a heated surface (like when the sun heats the earth’s surface) strongly attenuates the heating ability of increasing backscatter from increased amount of CO<sub>2</sub> in the atmosphere. This result has consequences for the climate change models used by IPCC. 展开更多
关键词 Greenhouse Effect CO2 Backscatter ir radiation
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Characteristics of radiation and convection heat transfer in indirect near-infrared-ray heating chamber 被引量:1
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作者 CHOI Hoon-ki YOO Geun-jong KIM Churl-hwan 《Journal of Central South University》 SCIE EI CAS 2011年第3期731-738,共8页
Numerical study was performed to evaluate the characteristics of combined heat transfer of radiation, conduction and convection in indirect near infrared ray (N/R) heating chamber. The effects of important design pa... Numerical study was performed to evaluate the characteristics of combined heat transfer of radiation, conduction and convection in indirect near infrared ray (N/R) heating chamber. The effects of important design parameters such as the shape of heat absorbing cylinder and heat releasing fin on the pressure drop and heat transfer coefficient were analyzed with different Reynolds numbers. The Reynolds numbers were varied from 103 to 3x106, which was defined based on the hydraulic diameter of the heat absorbing cylinder. Analyses were performed to obtain the inner and outer flow and the temperature distributions in the heat absorbing cylinder and the rates of radiation heat transfer and convection heat transfer. As the Reynolds number increases, the convection heat transfer rate is increased while the radiation heat transfer rate is decreased. The average convection heat transfer rate follows a power rule of the Reynolds number. Addition of three-dimensional heat releasing fin to the outside of the heat absorbing cylinder enhances the convection heat transfer. 展开更多
关键词 near infrared ray indirect near infrared ray heater absorbing cylinder heat releasing fin radiation heat transfer convection heat transfer Reynolds number
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新吲哚菁绿IR-820辅助的近红外荧光成像和光热及协同治疗在肿瘤诊疗中的应用进展
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作者 朱丽君 樊慧敏 +4 位作者 李慧 杜仲 王蕾 张学良 努尔尼沙·阿力甫 《中国材料进展》 CAS CSCD 北大核心 2024年第8期734-742,共9页
新吲哚菁绿IR-820因其具有强近红外(near-infrared,NIR,750~1700 nm)荧光特性、良好生物相容性、高光热转换效率及稳定性等优势,在NIR发光的有机荧光染料中脱颖而出,被广泛应用于生物医学成像、荧光标记、细胞实时监测、光热治疗等研究... 新吲哚菁绿IR-820因其具有强近红外(near-infrared,NIR,750~1700 nm)荧光特性、良好生物相容性、高光热转换效率及稳定性等优势,在NIR发光的有机荧光染料中脱颖而出,被广泛应用于生物医学成像、荧光标记、细胞实时监测、光热治疗等研究领域。为更好地发挥IR-820的生物医学应用价值,研究人员用不同生物化学分子修饰IR-820来增强其荧光及光热特性,制备多种类的荧光纳米粒子,在基础生物医学成像与肿瘤光热治疗方面开展了众多研究。总结了IR-820荧光纳米粒子在近红外荧光成像和通过光热机理及与其他技术协同治疗肿瘤中的应用研究,希望为进一步推进有机荧光染料IR-820在生物医学领域应用和临床转化发展提供参考。 展开更多
关键词 有机荧光染料 新吲哚菁绿ir-820 近红外荧光成像 光热治疗 协同治疗 肿瘤
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Infrared microspectroscopy beamline BL06B at SSRF
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作者 Te Ji Hua-Chun Zhu +4 位作者 Wei-Wei Peng Jie Wang Hong-Wei Zhao Ai-Guo Li Min Chen 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第1期10-17,共8页
The infrared microspectroscopy beamline(BL06B) is a phase Ⅱ beamline project at the Shanghai Synchrotron Radiation Facility(SSRF). The construction and optical alignment of BL06B were completed by the end of 2020. By... The infrared microspectroscopy beamline(BL06B) is a phase Ⅱ beamline project at the Shanghai Synchrotron Radiation Facility(SSRF). The construction and optical alignment of BL06B were completed by the end of 2020. By 2021, it became accessible to users. The synchrotron radiation infrared(SRIR) source included edge radiation(ER) and bending magnet radiation(BMR). The extracted angles in the horizontal and vertical directions were 40 and 20 mrad, respectively. The photon flux, spectral resolution, and focused spot size were measured at the BL06B endstation, and the experimental results were consistent with theoretical calculations. SRIR light has a small divergence angle, high brightness, and a wide wavelength range. As a source of IR microscopy, it can easily focus on a diffraction-limited spatial resolution with a high signal-to-noise ratio(SNR). The BL06B endstation can be applied in a wide range of research fields, including materials, chemistry, biology, geophysics, and pharmacology. 展开更多
关键词 Synchrotron radiation infrared beamline infrared microspectroscopy
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THIRTY-SIX CASES OF NEURITIS OF LATERAL CUTANEOUS NERVE OF THIGH TREATED BY MAGNETIC ROUND PLUM-BLOSSOM NEEDLE PLUS INFRARED RADIATION
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作者 罗立新 李唯 《World Journal of Acupuncture-Moxibustion》 1996年第4期34-36,共3页
Thirty-six cases of neuritis of lateral cutaneous nerve of thigh were treated by mag-netic round plum-blossom needle plus infrared radiation and it was compared with simpleacupuncture treatment.Statistical analysis in... Thirty-six cases of neuritis of lateral cutaneous nerve of thigh were treated by mag-netic round plum-blossom needle plus infrared radiation and it was compared with simpleacupuncture treatment.Statistical analysis indicated that there was no significant difference in thetheraPeutic effects between the two methods,but magnetic round Plum-blossom needle Plus in-frared radiation had as high therapeutic effect as simple acupuncture treatment and with themethod pateints suffered less without infection and it was easily to be accepted by patients. 展开更多
关键词 NEURITIS of lateral cuteneous nerve of THIGH Magnetic round plum-blossom NEEDLE infrared radiation Simple acupuncture
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Instability of Nucleic Acids in Airborne Microorganisms under Far Infrared Radiation
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作者 En-Jing Li Jun Lu +4 位作者 Shu-Ming Dong Mei-Zi Zhang Steven Cen Lian-Jing Li Wei-Hong Huang 《Health》 2020年第8期998-1007,共10页
Emergence of zoonotic-human pathogens is proven to be a lethal threat to public health, and RNA virus including influenza viruses, severe acute respiratory syndrome coronavirus, middle east respiratory syndrome corona... Emergence of zoonotic-human pathogens is proven to be a lethal threat to public health, and RNA virus including influenza viruses, severe acute respiratory syndrome coronavirus, middle east respiratory syndrome coronavirus, and COVID-19, plays a pivotal role. As those viruses as airborne microorganisms spread mainly by tiny airborne particles, it is important to de-active those airborne particles before their entry into human bodies. In this study, we investigated the effect of far infrared (FIR) radiation on inhibition of airborne microorganisms. The result confirmed that double stand DNA from airborne microorganisms containing RNA viruses was stable under mild FIR radiation. However, single strand RNA from them was found to be sensitive to FIR radiation, indicating that RNA virus in airborne particles is instable under FIR radiation. Based on this observation, two models on usage of FIR radiation to prevent RNA virus transmission by air and cure RNA virus infection were proposed. Then, this study suggests that FIR radiation has the potential to be a cheap, convenient, and efficient method in clinic to treat RNA virus. 展开更多
关键词 RNA Virus Far infrared radiation Influenza Virus COVID-19
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CO2 Back-Radiation Sensitivity Studies under Laboratory and Field Conditions
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作者 Ernst Hammel Martin Steiner +4 位作者 Christoph Marvan Matthias Marvan Klaus Retzlaff Werner Bergholz Axel Jacquine 《Atmospheric and Climate Sciences》 2024年第4期407-428,共22页
We measured the IR back radiation using a relatively low-cost experimental setup and a test chamber with increasing CO2 concentrations starting with a pure N2 atmosphere against a temperature-controlled black referenc... We measured the IR back radiation using a relatively low-cost experimental setup and a test chamber with increasing CO2 concentrations starting with a pure N2 atmosphere against a temperature-controlled black reference background. The results confirm estimations within this work and previous finding about CO2-induced infrared radiation saturation within realistic atmospheric conditions. We used this setup also to study thermal forcing effects with stronger and rare greenhouse gases against a clear night sky. Our results and their interpretation are another indication for having a more critical approach in climate modelling and against monocausal interpretation of climate indices only caused by anthropogenic greenhouse gas emissions. Basic physics combined with measurements and data taken from the literature allow us to conclude that CO2 induced infrared back-radiation must follow an asymptotic logarithmic-like behavior, which is also widely accepted in the climate-change community. The important question of climate sensitivity by doubling current CO2 concentrations is estimated to be below 1˚C. This value is important when the United Nations consider climate change as an existential threat and many governments intend rigorously to reduce net greenhouse gas emissions, led by an ambitious European Union inspired by IPCC assessments is targeting for more than 55% in 2030 and up to 100% in 2050 [1]. But probably they should also listen to experts [2] [3] who found that all these predictions have considerable flaws in basic models, data and impact scenarios. 展开更多
关键词 Climate Change Greenhouse Gases CO2 Backscatter ir radiation
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Effect of Infrared Irradiation Combined with External Application Nursing on Maintenance of Vascular Access in Hemodialysis Patients
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作者 Qi Liu 《Journal of Clinical and Nursing Research》 2021年第2期46-49,共4页
Objective:This paper mainly analyzes the effect of infrared radiation combined with external application nursing on maintenance of vascular access in hemodialysis patients.Methods:A total of 150 hemodialysis patients ... Objective:This paper mainly analyzes the effect of infrared radiation combined with external application nursing on maintenance of vascular access in hemodialysis patients.Methods:A total of 150 hemodialysis patients in our hospital from December 2019 to September 2020 were divided into the conventional group and the study group,75 cases in each group.The conventional group was given external application nursing alone,and the study group was given infrared radiation combined with external application nursing,and the effect on the maintenance of vascular access was counted.Results:After the intervention,the indexes of URR,kt/V and human albumin in the study group were higher than those in the routine group,and the indexes of β2-mg and MIS in the study group were lower than those in the routine group,P<0.05;The improvement of vascular elasticity and quality of life in the study group was higher than that in the conventional group,and the incidence of complications was lower than that in the conventional group,P<0.05.Conclusion:Infrared radiation combined with external application of nursing care in hemodialysis patients with vascular access maintenance effect is significant,can effectively improve vascular elasticity. 展开更多
关键词 infrared radiation External application nursing HEMODIALYSIS Vascular access maintenance
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RELATIONSHIP BETWEEN INFRARED RADIATION AND CRYSTAL STRUCTURE IN Fe-Mn-Co-Cu-O SPINELS 被引量:6
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作者 Y. Zhang D.J. Wen 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2008年第1期15-20,共6页
Ni^3+ and Cr^3+ doped Fe-Mn-Co-Cu-O spinels have been prepared by solid phase sintering. The valence states and distribution of transition ions in the spinel crystals are inferred by the consideration of thermodynam... Ni^3+ and Cr^3+ doped Fe-Mn-Co-Cu-O spinels have been prepared by solid phase sintering. The valence states and distribution of transition ions in the spinel crystals are inferred by the consideration of thermodynamic principle and crystalline field theory. The mierostructure and performance of those are studied by X-ray diffraction (XRD), Fourier transform infrared (FT-IR), and IRE-2 infrared radiant instrument. Ni3+ and Cr3+ occupy the vacancies or substitute the other ions in the spinel structures and form diverse spinel structures, which exhibit infrared integral emissivities of 0.93 in the whole band, and 0. 94 in the band within 14-25μm too. The content of Fe2O3 and MnO2 in the spinel crystals changes, maybe it induces infrared radiativity of spinels differently. 展开更多
关键词 Crystal structure MINERAL infrared radiation property
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Experimental Study of Deformation of Sur- rounding Rock with Infrared Radiation 被引量:6
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作者 ZHANG Yong-jun AN Li-qian +4 位作者 REN Run-hou FAN Shi-min MA Nian-jie LI Jian-hui JI Yuan-ming 《Journal of China University of Mining and Technology》 EI 2005年第4期329-333,共5页
According to the practical conditions of coal roadway in Changcun Coal Mine of Lu'an Mining Group, the deformation of rock surrounding roadway was experimentally studied by means of thermal infrared (TIP,) imaging ... According to the practical conditions of coal roadway in Changcun Coal Mine of Lu'an Mining Group, the deformation of rock surrounding roadway was experimentally studied by means of thermal infrared (TIP,) imaging system in the process of confined compressions. It is found that the model surface TIR temperature (TIRT) changes with the increase of load. Furthermore, TIRT changes non-synchronously in different ranges such as the roof, floor, wall, corners and bolted ranges. The TIRT is higher in the location of stress concentration and bolted ranges than that in the location of stress relaxation and broken ranges. The interaction ranges of bolt and rock are determined preliminarily according to the corresponding relationship of TIRT fields and the strain fields of the surrounding rock. The new method of TIR image processing has been proved to be effective for the study of bolt support and observation of roadway stability under mine pressure. 展开更多
关键词 bolt support surrounding rock infrared radiation physical model test
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EXPERIMENTAL STUDY ON THE INFRARED RADIATION CHARACTERISTICS FROM HOT JET 被引量:1
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作者 Shan Qixiang Bu Man(College of Science, Nanjing University of Aeronautics and Astronautics, Nanjing, Chinaa, 210016)Zhen Libao(Department of Power Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing, China, 210016) 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 1996年第3期187-192,共6页
An experimental study on infrared radiation from the hot jet by means of model test is presented. The infrared detection system of the universal infrared instruments. the testing method and experimental results of inf... An experimental study on infrared radiation from the hot jet by means of model test is presented. The infrared detection system of the universal infrared instruments. the testing method and experimental results of infrared radiation from the hot jet are introduced. The space distribution of infaed radiant energy. the spectrum of infrared radiation from the hot jet. the distribution of the radiant energy of the hot jet against the wavebands and the characteristic difference of the hot jet radiaton between the 2-D jet tube and the circular jet tube are obtained. It is indicated that the testing system and the method are valid and the results are in accord with the theoretical analysis. 展开更多
关键词 hot jets infrared radiation TESTS spectrum analysis
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Quantitative description of infrared radiation characteristics for solid materials subjected to external loading 被引量:2
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作者 王芳 李英骏 +1 位作者 饶秋华 唐炼 《Journal of Central South University》 SCIE EI CAS 2009年第6期1022-1027,共6页
Based on the thermodynamics theory and physical micro-properties of solid materials subjected to external loading at room temperature,a formula of calculating temperature difference of infrared radiation in terms of t... Based on the thermodynamics theory and physical micro-properties of solid materials subjected to external loading at room temperature,a formula of calculating temperature difference of infrared radiation in terms of the sum of three principal strains was deduced to quantitatively investigate the infrared radiation characteristics in test. Two typical specimens,the three-point bending beam and the disc pressed in diameter,were tested and their principal strains were calculated by finite element method in order to obtain the temperature differences of infrared radiation. Numerical results are in a good agreement with test results,which verifies the validity of the formula of calculating temperature differences of infrared radiation and the model of quantitatively describing the infrared radiation characteristics of solid materials,and reveals the corresponding inner physical mechanism. 展开更多
关键词 infrared radiation characteristics thermodynamics analysis numerical simulation strain tensor
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Structure and Infrared Radiation Properties of Substituted Cordierites 被引量:1
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作者 徐庆 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2006年第4期68-70,共3页
Zn^2+ - or Ti^4+ -substituted cordierites with the nominal compositions of Mg1 .6 Zn0.4 Al4 Si5 O18 and Mg1.8 Ti0.2 Al4.4 Si4.6 O18 respectively, were prepared by a conventional solid state reaction method. The stru... Zn^2+ - or Ti^4+ -substituted cordierites with the nominal compositions of Mg1 .6 Zn0.4 Al4 Si5 O18 and Mg1.8 Ti0.2 Al4.4 Si4.6 O18 respectively, were prepared by a conventional solid state reaction method. The structure of the substituted eordierites was characterized by X- ray diffraction ( XRD ), infrared ( 1R ) spectroscopy and 29 Si magic angle spinning ( MAS ) nuclear magnetic resonance ( NMR ). The infoared radiation properties were investigated in the bands within 2.5-25μm. Compared with the na-substituted cordierite composition ( Mg2 Al4 Si5 O18 ), Zn^2+ - or Ti^4+ -substituted cordierites show superior infrared properties. XRD and IR results confirm the formation of hexagonal a-eordierite as the main eo'stal phase for the substituted cordierites. 29 Si MAS NMR result indicates that Zn^2+ or Ti^4+ Substitutions for partial Mg^2+ of a-eordierite promoted the ordering of the distribution oral and Si atoms in T1 ( tetrahedra connecting six-raembered rings together with [ MgO6] octahedra ) and T2 ( tetraheda forming six-reentered rings) tetrahedral sites. This resulted in a lattice deformation and increased the anharmonicity of polarization vibration, which is responsible for the improvement of infrared radiation properties of the substituted eordierites. 展开更多
关键词 α-eordierite infrared radiation properties SUBSTITUTION 29 Si MAS NMR
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Test research on IR radiation characteristics control of space target using cryogenic vacuum multilayer insulation film structure 被引量:1
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作者 卢春莲 周彦平 付森 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2011年第4期119-122,共4页
In order to achieve the objective of controlling IR radiation characteristics of space target,we design multilayer insulation film structure to cover the target.In space environment the structure comes to cryogenic va... In order to achieve the objective of controlling IR radiation characteristics of space target,we design multilayer insulation film structure to cover the target.In space environment the structure comes to cryogenic vacuum multilayer insulation film structure.It can quickly lower the surface temperature of space target,approaching to the ultra-low temperature of the space environment.A vacuum simulation verification test was designed and performed.Through the analysis of test results,we can see that the surface temperature of space target covered by the structure changes with the ambient temperature,having no direct relationship with internal temperature of the target.Therefore,the designed cryogenic vacuum multilayer insulation film structure has excellent IR radiation control performance.It can reduce the target’s IR radiation intensity so as to reduce the probability of detection by IR detectors. 展开更多
关键词 ir radiation CRYOGENIC VACUUM insulation film space target
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Infrared radiation method for measuring ice segregation temperature of artificially frozen soils 被引量:3
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作者 Zhou Guoqing Zhang Qi +1 位作者 Xu Zhiwei Zhou Yang 《International Journal of Mining Science and Technology》 2012年第1期35-40,共6页
In order to study the evolution of the freezing fringe and final lenses of frost susceptible soils and advance the understanding of frost heave and mechanism of frost heave control, we used an open one-dimensional fro... In order to study the evolution of the freezing fringe and final lenses of frost susceptible soils and advance the understanding of frost heave and mechanism of frost heave control, we used an open one-dimensional frost heave test system of infrared radiation technology, instead of a traditional thermistor method. Temperatures of the freezing fringe and segregated ice were measured in a non-contact mode. The results show that accurate and precise temperatures of ice segregation can be obtained by infrared thermal imaging systems. A self-developed inversion program inverted the temperature field of frozen soils. Based on our analysis of temperature variation in segregated ice and our study of the relationship between temperature and rate of ice segregation in cooling and warming processes during intermittent freezing, the mechanism of decreasing frost heave of frozen soils by controlling the growth of final lenses with an intermittent freezing mode, can be explained properly. 展开更多
关键词 One-dimensional freezing Final lens Ice segregation temperature measurement infrared radiation method
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高剂量率^(192)Irγ射线参考辐射场的搭建 被引量:1
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作者 支世杰 王继 +2 位作者 王培玮 吴金杰 任世伟 《计量学报》 CSCD 北大核心 2023年第12期1882-1888,共7页
为完成高剂量率^(192)Ir放射源参考空气比释动能率的绝对测量工作,设计了专用的辐照器及定位装置,利用医用高剂量率近距离治疗机搭建了准直的参考辐射场。参考ISO 4037等相关标准,对参考辐射场的散射、辐射野、半值层、有效能量等相关... 为完成高剂量率^(192)Ir放射源参考空气比释动能率的绝对测量工作,设计了专用的辐照器及定位装置,利用医用高剂量率近距离治疗机搭建了准直的参考辐射场。参考ISO 4037等相关标准,对参考辐射场的散射、辐射野、半值层、有效能量等相关参数进行了测量和研究。结果显示,在辐射场多个位置,环境散射份额小于主射束的0.003%;在距离放射源1.4 m的位置,辐射野直径为98 mm,尺寸大于基准石墨空腔电离室;半值层测量结果为8.224 mm(Cu),有效能量为402.8 keV,利用HPGe探测器测量的^(192)Ir能谱与模拟谱契合度良好。各项参数均满足了^(192)Ir近距离治疗源参考空气比释动能率的量值复现要求,为其绝对测量与国际比对工作打下基础。 展开更多
关键词 电离辐射 参考空气比释动能率 近距离治疗 ^(192)ir放射源
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Quantitative description of infrared radiation characteristics of preflawed sandstone during fracturing process 被引量:1
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作者 Ke Zhang Xianghua Liu +1 位作者 Yulong Chen Heming Cheng 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2021年第1期131-142,共12页
Previous studies show that infrared radiation temperature(IRT)abnormalities are always accompanied by the crack development in rocks under external loads.In this context,experiments were conducted on preflawed sandsto... Previous studies show that infrared radiation temperature(IRT)abnormalities are always accompanied by the crack development in rocks under external loads.In this context,experiments were conducted on preflawed sandstone to investigate the infrared radiation characteristics during failure process.Two indicators were defined herein,i.e.coefficient of variation of IRT(CVIRT)and skewness of IRT(SIRT).The regression analysis shows that the IRT probability distributions during loading process fit the Gaussian model.The variations in the CVIRT are characterized by four stages:primary stage,steady stage,accelerating stage and post-peak stage.Besides,the variations in the SIRT are divided into three stages:primary stage,steady stage and failure and post-peak stage.The precursor point for preflawed rock failure is identified based on the CVIRTetime curve,with average precursor point of 83%of the peak stress.Compared with other IRT indicators,the proposed two IRT indicators have higher sensitivity to IRT abnormalities during failure process.Furthermore,the connection between the IRT indicators and the rock fracturing was investigated to interpret the IRT indicator abnormalities.Based on the Verhulst inverse function,a new quantitative model was presented to describe the primary stage,steady stage and accelerating stage of the CVIRTetime curve.The results obtained in this study can provide early-warning information for rock failure prediction. 展开更多
关键词 Remote sensing rock mechanics infrared radiation characteristics STATISTICS Precursor point Verhulst inverse model
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First Order Phase Transitions as Radiation Processes 被引量:1
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作者 Vitali A. Tatartchenko Pavel V. Smirnov Yong Wu 《Optics and Photonics Journal》 2013年第8期1-12,共12页
This paper presents new experimental evidence of the PeTa effect—infrared characteristic radiation under first order phase transitions, especially the crystallization of melts and the deposition and condensation of v... This paper presents new experimental evidence of the PeTa effect—infrared characteristic radiation under first order phase transitions, especially the crystallization of melts and the deposition and condensation of vapours/gases. The PeTa effect describes the transient radiation that a particle (i.e., atom, molecule or/and cluster) emits transient radiation during a transition from a meta-stable higher energetic level (in a super-cooled melt or a super-saturated vapour) to the stable condensed lower level (in a crystal or a liquid). The radiation removes latent heat with photons of characteristic frequencies that are generated under this transition. The abbreviation “PeTa effect” means Perel’man-Tatartchenko’s effect. 展开更多
关键词 Peta Effect First Order Phase TRANSITIONS VAPOUR CONDENSATION VAPOUR Deposition MELT CRYSTALLIZATION infrared radiation Atmospheric Phenomena
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