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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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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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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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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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Combination of genistein with ionizing radiation on andro-gen-independent prostate cancer cells 被引量:5
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作者 Sen-XiangYan YasuoEjima +4 位作者 RyoheiSasaki Shu-SenZheng YusukeDemizu ToshinoriSoejima KazuroSugimura 《Asian Journal of Andrology》 SCIE CAS CSCD 2004年第4期285-290,共6页
Aim: To study the effect of the combined use of genistein and ionizing radiation (IR) on prostate DU145 cancer cells. Methods: DU145, an androgen-independent human prostate cancer cell line, was used in the experiment... Aim: To study the effect of the combined use of genistein and ionizing radiation (IR) on prostate DU145 cancer cells. Methods: DU145, an androgen-independent human prostate cancer cell line, was used in the experiment. Clonogenic assay was used to compare the survival of DU145 cells after treatments with genistein alone and in combination with graded IR. Apoptosis was assayed by DNA ladder and TUNEL stain. Cell cycle alterations were observed by flow cytometry and related protein expressions by immunoblotting. Results: Clonogenic assay demonstrated that genistein, even at low to medium concentrations, enhanced the radiosensitivity of DU145 cells. Twenty-four hours after treatment with IR and/or genistein, apoptosis was mainly seen with genistein at high concentrations and was minimally related to IR. At 72 h, apoptosis also occurred in treatment with lower concentration of genistein, especially when combined with IR. While both IR and genistein led to G2/M cell cycle arrest, combination of them further increased the DU145 cells at G2/M phase. This Gz/M arrest was largely maintained at 72 h, accompanied by increasing apoptosis and hyperdiploid cell population. Cell-cycle related protein analysis disclosed biphasic changes in cyclin B1 and less dramatically cdc-2, but stably elevated p21cipl levels with increasing genistein concentrations. Conclusion: Genistein enhanced the radiosensitivity of DU145 prostate cancer cells. The mechanisms might be involved in the increased apoptosis, prolonged cell cycle arrest and impaired damage repair. 展开更多
关键词 prostate cancer GENISTEIN ionizing radiation (ir) APOPTOSIS cell cycle
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Size control synthesis of sulfur doped titanium dioxide (anatase) nanoparticles,its optical property and its photo catalytic reactivity for CO_2 + H_2O conversion and phenol degradation 被引量:8
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作者 S. Tajammul Hussain Khaiber Khan R. Hussain 《Journal of Natural Gas Chemistry》 CAS CSCD 2009年第4期383-391,共9页
Sulfur doped anatase TiO2 nanoparticles (3 nm- 12 nm) were synthesized by the reaction of titanium tetrachloride, water and sulfuric acid with addition of 3 M NaOH at room temperature. The electro-optical and photoc... Sulfur doped anatase TiO2 nanoparticles (3 nm- 12 nm) were synthesized by the reaction of titanium tetrachloride, water and sulfuric acid with addition of 3 M NaOH at room temperature. The electro-optical and photocatalytic properties of the synthesized sulfur doped TiO2 nanoparticles were studied along with Degussa commercial TiO2 particles (24 nm). The results show that band gap of TiO2 particles decreases from 3.31 to 3.25 eV and for that of commercial TiO2 to 3.2 eV when the particle sizes increased from 3 nm to 12 nm with increase in sulfur doping. The results of the photocatalytic activity under UV and sun radiation show maximum phenol conversion at the particle size of 4 nm at 4.80% S-doping. Similar results are obtained using UV energy for both phenol conversion and conversion of CO2+H2O in which formation of methanol, ethanol and proponal is observed. Production of methanol is also achieved on samples with a particle size of 8 and 12 nm and sulfur doping of 4.80% and 5.26%. For TiO2 particle of 4 nm without S doping, the production of methanol, ethanol and proponal was lower as compared to the S-doped particles. This is attributed to the combined electronic effect and band gap change, S dopant, specific surface area and the light source used. 展开更多
关键词 S doped TiO2 PHOTOCATALYST CO2 conversion phenol degradation UV ir radiation
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Unexpected Relationships between Thermal and Radiative Energy Transfer
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作者 Thorstein O. Seim Borgar T. Olsen 《Atmospheric and Climate Sciences》 2020年第4期639-651,共13页
A simple experiment is described where the IR (infrared) radiation level is kept constant while the temperature of an IR absorbing and a non-absorbing solid object are changed. The two objects, made from black-painted... A simple experiment is described where the IR (infrared) radiation level is kept constant while the temperature of an IR absorbing and a non-absorbing solid object are changed. The two objects, made from black-painted and highly polished Al foil envelopes, respectively, are placed in a chamber where the temperature is controlled. When heated by the surrounding air the black object becomes about 40% colder than the non-IR absorbing object! However, when the two objects are cooled by the surrounding air, the black becomes ca. 40% warmer than the non-IR absorbing object (and the surrounding air). This effect was surprising to us, and it gave us an opportunity to quantify the relationship between IR radiation flow and thermal energy flow. The unexpected large value of the (Fourier) thermal conductivity coefficient was found to be the reason for the reduced warming/cooling of the black object. The interaction between radiative and thermal energy transfer, when an IR absorbing object (like the surface of the Earth) is warmed, should be included in the climate models used by the Intergovernmental Panel on Climate Change (IPCC), since the global land temperature is measured in the air above Earth’s surface. This leads to ca. 15% of the temperature increase predicted by the climate models. 展开更多
关键词 ir radiation Thermal Energy Transfer Global Warming Models
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Inhibition of human esophageal squamous cell carcinomas by targeted silencing of tumor enhancer genes: an overview
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作者 Jalil Pirayesh Islamian Mohsen Mohammadi Behzad Baradaran 《Cancer Biology & Medicine》 SCIE CAS CSCD 2014年第2期78-85,共8页
Esophageal cancer has been reported as the ninth most common malignancy and ranks as the sixth most frequent cause of death worldwide. Esophageal cancer treatment involves surgery, chemotherapy, radiation therapy, or ... Esophageal cancer has been reported as the ninth most common malignancy and ranks as the sixth most frequent cause of death worldwide. Esophageal cancer treatment involves surgery, chemotherapy, radiation therapy, or combination therapy. Novel strategies are needed to boost the oncologic outcome. Recent advances in the molecular biology of esophageal cancer have documented the role of genetic alterations in tumorigenesis. Oncogenes serve a pivotal function in tumorigenesis. Targeted therapies are directed at the unique molecular signature of cancer cells for enhanced efficacy with low toxicity. RNA interference(RNAi) technology is a powerful tool for silencing endogenous or exogenous genes in mammalian cells. Related results have shown that targeting oncogenes with siRNAs, specifically the mRNA, effectively reduces tumor cell proliferation and induces apoptotic cell death. This article will briefly review studies on silencing tumor enhancer genes related to the induction of esophageal cancer. 展开更多
关键词 Esophageal carcinoma ionizing radiationir oncogene targeted therapy sirNA
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Infrared radiation simulation of exhaust system by coupling FVM with narrow band k-distribution 被引量:5
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作者 ZHU Xi-juan Eriqitai +1 位作者 LI Xi-xi WANG Qiang 《航空动力学报》 EI CAS CSCD 北大核心 2012年第1期25-32,共8页
A three-dimensional infrared radiation code for exhaust system was developed by the finite volume method coupled with narrow band k-distribution in non-gray absorbing-emitting media.The final infrared signature had co... A three-dimensional infrared radiation code for exhaust system was developed by the finite volume method coupled with narrow band k-distribution in non-gray absorbing-emitting media.The final infrared signature had considered the atmosphere effect,and the simulation values were favorably consistent with testing ones.The results indicate that the relative errors considering the effect of atmosphere compared with that of the contrary condition reduce by 31%,it shows that when simulating the infrared radiation of the target which is received by the infrared detectors,even the calculation band is in atmospheric windows 3~5 μm,the effect of atmospheric transmission on infrared signature of the target should not be neglected. 展开更多
关键词 exhaust system infrared radiation(ir) finite volume method(FVM) narrow band k-distribution atmospheric transmission
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Independent dual-responsive Janus chromic fibers 被引量:3
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作者 Yanfang Wei Wei Zhang +3 位作者 Chengyi Hou Qinghong Zhang Yaogang Li Hongzhi Wang 《Science China Materials》 SCIE EI CAS CSCD 2021年第7期1770-1779,共10页
Daily exposure under solar ultraviolet(UV)and infrared(IR)is prone to cause skin cancer and photoaging.Real-time monitoring of the environmental UV index and IR radiation temperature during outdoor activities can enha... Daily exposure under solar ultraviolet(UV)and infrared(IR)is prone to cause skin cancer and photoaging.Real-time monitoring of the environmental UV index and IR radiation temperature during outdoor activities can enhance awareness and strengthen personal protection.It is a challenge to design flexible,wearable devices(with measurement capabilities)that can be integrated with apparels.Here,microfluidic spinning technology(MST)was used for the continuous and large-scale fabrication of eco-friendly coresheath Janus fibers with a well-defined axially symmetric Janus core.One side of the core was sensitive to UV light and the opposite was sensitive to IR radiation.Textiles woven with Janus fibers showed excellent independent reversible color responses to dual-wavelength stimulation.Such textiles switched among four colors under UV and IR irradiation,both individually and in combination.The color gradient of the textiles changed significantly with increasing UV intensity(UV index).After 60 cycles of UV/IR stimulation and 50 washes,the change rate of the comprehensive chromatic aberration(ΔE_(ab)^(*))of the textiles under different conditions was only 0.42%-4.71%.This was attributed to the unique structure of the fibers.The three-line striped textiles demonstrated the potential of the fibers to be used as wearable energy-free realtime visual monitors of the UV index and IR radiation temperature. 展开更多
关键词 microfluidic spinning UV index ir radiation temperature dual-wavelength response core-sheath Janus fibers
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