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Preparation and Thermal Stability of AlMoON Based Solar Selective Absorption Coating
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作者 闵捷 YUAN Wenxu +5 位作者 CHEN Yufei LAN Yapeng YAN Mengdi LIU Hanze CHENG Xudong 代路 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第4期854-862,共9页
AlMoON based solar selective absorption coatings were deposited on stainless steel substrate by magnetron sputtering.The coatings included infrared reflection layer Mo,absorption layer AlMoN,absorption layer AlMoON an... AlMoON based solar selective absorption coatings were deposited on stainless steel substrate by magnetron sputtering.The coatings included infrared reflection layer Mo,absorption layer AlMoN,absorption layer AlMoON and antireflection layer AlMoO from bottom to top.The surface of the deposited coatings is flat without obvious defects.The absorptivity and emissivity are 0.896 and 0.09,respectively,and the quality factor is 9.96.After heat treatment at 500℃-36 h,the surface roughness of the coating increases,a small number of cracks and other defects appear,and the broken part is still attached to the coating surface.A certain degree of element diffusion occurs in the coatings,resulting in the decline of the optical properties of the coatings.The absorptivity and emissivity are 0.883 and 0.131,respectively,the quality factor is 7.06,and the PC value is 0.0335.The coatings do not fail under this condition and have certain thermal stability. 展开更多
关键词 AlMoON COATING PREPARATION thermal stability
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Significantly enhanced thermal stability of HMX by phase-transition lysozyme coating
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作者 Jiahui Liu Congmei Lin +3 位作者 Jianhu Zhang Chengcheng Zeng Zhijian Yang Fude Nie 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第5期60-68,共9页
A new robust bio-inspired route by using lysozyme aqueous solution for surface modification on 1,3,5,7-tetranitro-1,3,5,7-tetrazocane(HMX)was described in this paper.HMX crystals were coated by in situ phase transitio... A new robust bio-inspired route by using lysozyme aqueous solution for surface modification on 1,3,5,7-tetranitro-1,3,5,7-tetrazocane(HMX)was described in this paper.HMX crystals were coated by in situ phase transition of lysozyme(PTL)molecules.The HMX decorated by PTL was characterized by SEM,XRD,FTIR and XPS,demonstrating a dense core-shell coating layer.The coverage of lysozyme on HMX crystal was calculated by the ratio of sulfur content.The surface coverage increased from 60.5% to 93.5% when the content of PTL was changed from 0.5 wt% to 2.0 wt%,indicating efficient coating.The thermal stability of HMX was investigated by in situ XRD and DSC.The thermal phase transition temperature of HMX(β to δ phase)was delayed by 42℃ with 2.0 wt% PTL coating,which prevented HMX from thermal damage and sensitivity by the effect of PTL coating.After heating at 215℃,large cracks appeared in the naked HMX crystal,while the PTL coated HMX still maintained intact,with the impact energy of HMX dropped dramatically from 5 J to 2 J.However,the impact energy of HMX with 1.0 wt% and 2.0 wt% coating content(HMX@PTL-1.0 and HMX@PTL-2.0)was unchanged(5 J).Present results potentially enable large-scale fabrication of polymorphic energetic materials with outstanding thermal stability by novel lysozyme coating. 展开更多
关键词 HMX LYSOZYME Phase transition thermal stability Sensitivity
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Theoretical insights into thermal transport and structural stability mechanisms of triaxial compressed methane hydrate
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作者 Dong-Sheng Chen Ting-Ting Miao +3 位作者 Cheng Chang Xu-Yang Guo Meng-Yan Guan and Zhong-Li Ji 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第9期494-504,共11页
The heat transfer and stability of methane hydrate in reservoirs have a direct impact on the drilling and production efficiency of hydrate resources,especially in complex stress environments caused by formation subsid... The heat transfer and stability of methane hydrate in reservoirs have a direct impact on the drilling and production efficiency of hydrate resources,especially in complex stress environments caused by formation subsidence.In this study,we investigated the thermal transport and structural stability of methane hydrate under triaxial compression using molecular dynamics simulations.The results suggest that the thermal conductivity of methane hydrate increases with increasing compression strain.Two phonon transport mechanisms were identified as factors enhancing thermal conductivity.At low compressive strains,a low-frequency phonon transport channel was established due to the overlap of phonon vibration peaks between methane and water molecules.At high compressive strains,the filling of larger phonon bandgaps facilitated the opening of more phonon transport channels.Additionally,we found that a strain of0.04 is a watershed point,where methane hydrate transitions from stable to unstable.Furthermore,a strain of0.06 marks the threshold at which the diffusion capacities of methane and water molecules are at their peaks.At a higher strain of0.08,the increased volume compression reduces the available space,limiting the diffusion ability of water and methane molecules within the hydrate.The synergistic effect of the strong diffusion ability and high probability of collision between atoms increases the thermal conductivity of hydrates during the unstable period compared to the stable period.Our findings offer valuable theoretical insights into the thermal conductivity and stability of methane hydrates in reservoir stress environments. 展开更多
关键词 methane hydrate molecular dynamics thermal transport triaxial compression structural stability
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Thermal Stability and Degeneration Behavior of Solar Selective Absorber Based on WTi-Al_(2)O_(3)Cermet
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作者 WANG Xiaobo FANG Wei +2 位作者 MA Yuchao CHENG Xudong LI Kewei 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第6期1555-1564,共10页
A WTi-Al_(2)O_(3)cermet-based solar selective absorber was prepared to investigate the atomic diffusion induced spectral selectivity degeneration.The as-deposited coating exhibits superior absorptance(0.934)and low th... A WTi-Al_(2)O_(3)cermet-based solar selective absorber was prepared to investigate the atomic diffusion induced spectral selectivity degeneration.The as-deposited coating exhibits superior absorptance(0.934)and low thermal emittance(0.098),as well as excellent thermal stability with a selectivity of 0.900/0.07 even after annealing at 923 K for 400 h in Ar ambient.However,the multilayer coating failed after being subjected to annealing at 923 K for 400 h in an air environment,as indicated by a decrease in solar absorptance to 0.912 and an increase in thermal emittance to 0.634.The microstructure characterizations reveal that the annealed coating exhibits a columnar morphology along the vertical direction of the substrate.The presence of abundant grain boundaries in the multilayer coating promotes the outward diffusion of Cr and Mn atoms in the stainless-steel substrate.The Mn atoms,in particular,possess the capability to migrate towards the surface of the coating and undergo an oxidation reaction with oxygen,facilitating the formation of a thick Mn_(2)O_(3)layer.The roughness of the coating surface was significantly increased in this case,adversely affecting solar absorptance due to amplified sunlight reflection.In addition,the rocketing of thermal emittance is attributed to the destabilization of W infrared reflective layer during the annealing.These findings highlight the importance of considering the outward diffusion of Mn and Cr elements in the stainless-steel substrate when optimizing solar selective absorbers. 展开更多
关键词 solar selective absorber thermal stability spectral selectivity optical properties
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Construction of core@double-shell structured energetic composites with simultaneously enhanced thermal stability and safety performance
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作者 Peng Wang Wen Qian +6 位作者 Ruolei Zhong Fangfang He Xin Li Jie Chen Li Meng Yinshuang Sun Guansong He 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第4期134-142,共9页
The poor thermal stability and high sensitivity severely hinder the practical application of hexanitrohexaazaisowurtzitane(CL-20).Herein,a kind of novel core@double-shell CL-20 based energetic composites were fabricat... The poor thermal stability and high sensitivity severely hinder the practical application of hexanitrohexaazaisowurtzitane(CL-20).Herein,a kind of novel core@double-shell CL-20 based energetic composites were fabricated to address the above issues.The coordination complexes which consist of natural polyphenol tannic acid(TA) and Fe~Ⅲ were chosen to construct the inner shell,while the graphene sheets were used to build the outer shell.The resulting CL-20/TA-Fe~Ⅲ/graphene composites exhibited simultaneously improved thermal stability and safety performance with only 1 wt% double-shell content,which should be ascribed to the intense physical encapsulation effect from inner shell combined with the desensitization effect of carbon nano-materials from outer shell.The phase transition(ε to γ) temperature increased from 173.70 ℃ of pure CL-20 to 191.87℃ of CL-20/TA-Fe~Ⅲ/graphene composites.Meanwhile,the characteristic drop height(H_(50)) dramatically increased from 14.7 cm of pure CL-20 to112.8 cm of CL-20/TA-Fe~Ⅲ/graphene composites,indicating much superior safety performance after the construction of the double-shell structure.In general,this work has provided an effective and versatile strategy to conquer the thermal stability and safety issues of CL-20 and contributes to the future application of high energy density energetic materials. 展开更多
关键词 CL-20 Double-shell structure thermal stability Safety performance Tannic acid Graphene sheets
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Research progress on classification,source,application of phytosterol esters,and their thermal oxidation stability
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作者 Dami Li Shangde Sun Jingnan Chen 《Grain & Oil Science and Technology》 CAS 2024年第1期1-11,共11页
Phytosterol esters can effectively decrease serum cholesterol concentration in the human body and prevent cardio-cerebrovascular diseases.It was found that phytosterol esters exhibited better solubility and bioavailab... Phytosterol esters can effectively decrease serum cholesterol concentration in the human body and prevent cardio-cerebrovascular diseases.It was found that phytosterol esters exhibited better solubility and bioavailability than free phytosterols.In recent years,phytosterol esters have attracted increasing attention.However,during food processing,phytosterol esters are susceptible to degradation at high temperatures,resulting in certain losses and formation of potentially harmful substances for humans.This paper reviews the relevant literatures and updates on the thermal oxidation stability of phytosterol esters in recent years from the following aspects:(i)Sources,physiological activities,and applications of phytosterol esters;(ii)Oxidation mechanism of phytosterol esters;(iii)Effects of phytosterols species,the volume of addition,food matrix,heating temperature and time,and antioxidants on the thermal loss and oxidation stability of phytosterol esters.The research progress on the safety of phytosterol esters is also discussed in detail.Additionally,the prospects for future research are highlighted. 展开更多
关键词 thermal stability Loss rate Oxidation mechanism Phytosterol esters
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The Effect of Uncaria gambir on Optical Properties and Thermal Stability of CNF/PVA Biocomposite Films
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作者 Remon Lapisa Anna Niska Fauza +6 位作者 Dieter Rahmadiawan Krismadinata Dori Yuvenda Randi Purnama Putra Waskito Nandy Putra Hairul Abral 《Journal of Renewable Materials》 EI CAS 2024年第9期1593-1603,共11页
Cellulose-based film has gained popularity as an alternative to synthetic polymers due to its outstanding properties.Among all types of cellulose materials available,cellulose nanofiber(CNF)has great potential to be u... Cellulose-based film has gained popularity as an alternative to synthetic polymers due to its outstanding properties.Among all types of cellulose materials available,cellulose nanofiber(CNF)has great potential to be utilized in a diverse range of applications,including as a film material.In this study,CNF biocomposite film was prepared by using polyvinyl alcohol(PVA)as a matrix and Uncaria gambir extract as a filler.This study aims to investigate the effect of Uncaria gambir extract on the optical properties and thermal stability of the produced film.The formation of the CNF biocomposite films was confirmed using Fourier Transform Infrared Spectroscopy,their transmittance characteristics were measured using UV-Vis spectroscopy and a transmittance meter,while their reflectance was determined using a reflectance meter.The results revealed that the addition of Uncaria gambir extract to the CNF biocomposite film improved its UV-shielding properties,as indicated by the lower percentage of transmittance in the visible region,10%–70%.In addition,its reflectance increased to 10.6%compared to the CNF film without the addition of Uncaria gambir extract.Furthermore,the thermal stability of the CNF biocomposite film with the addition of Uncaria gambir extract improved to around 400℃–500℃.In conclusion,the results showed that CNF biocomposite film prepared by adding Uncaria gambir extract can be a promising candidate for optical and thermal management materials. 展开更多
关键词 Cellulose nanofiber biocomposite film optical properties Uncaria gambir thermal stability
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Further Analysis of Machine Tool Dimensional Accuracy and Thermal Stability under Varying Floor Temperature
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作者 Joel Arumun Shadrack Abiola 《World Journal of Engineering and Technology》 2024年第2期258-273,共16页
Machining is as old as humanity, and changes in temperature in both the machine’s internal and external environments can be of great concern as they affect the machine’s thermal stability and, thus, the machine’s d... Machining is as old as humanity, and changes in temperature in both the machine’s internal and external environments can be of great concern as they affect the machine’s thermal stability and, thus, the machine’s dimensional accuracy. This paper is a continuation of our earlier work, which aimed to analyze the effect of the internal temperature of a machine tool as the machine is put into operation and vary the external temperature, the machine floor temperature. Some experiments are carried out under controlled conditions to study how machine tool components get heated up and how this heating up affects the machine’s accuracy due to thermally induced deviations. Additionally, another angle is added by varying the machine floor temperature. The parameters mentioned above are explored in line with the overall thermal stability of the machine tool and its dimensional accuracy. A Robodrill CNC machine tool is used. The CNC was first soaked with thermal energy by gradually raising the machine floor temperature to a certain level before putting the machine in operation. The machine was monitored, and analytical methods were deplored to evaluate thermal stability. Secondly, the machine was run idle for some time under raised floor temperature before it was put into operation. Data was also collected and analyzed. It is observed that machine thermal stability can be achieved in several ways depending on how the above parameters are joggled. This paper, in conclusion, reinforces the idea of machine tool warm-up process in conjunction with a carefully analyzed and established machine floor temperature variation for the approximation of the machine tool’s thermally stability to map the long-time behavior of the machine tool. 展开更多
关键词 Dimensional Accuracy Machine Tool Machine Floor thermal stability TEMPERATURE thermal Deviation
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Development of a Thermal Fogger-specific Sedimentation Stabilizer 被引量:1
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作者 苏贤岩 何薇薇 +4 位作者 任学祥 陈莉 丁克坚 胡飞 叶正和 《Agricultural Science & Technology》 CAS 2017年第6期1120-1125,共6页
In order to solve the drifting away of thermal fog droplets during thermal spraying and the incompatibility between fog droplet carrier and conventional com- mercial agro-chemicals, the fog droplet carrier, surfactant... In order to solve the drifting away of thermal fog droplets during thermal spraying and the incompatibility between fog droplet carrier and conventional com- mercial agro-chemicals, the fog droplet carrier, surfactant, condensation nucleus ma- terial and antifreeze, dispersant, thickener and defoamer were screened and assem- bled to develop a thermal fog sedimentation stabilizer in this study, thereby provid- ing technical support for application and promotion of thermal spraying technology in pest and disease control in crops. 展开更多
关键词 thermal fogger Sedimentation stabilizer Fogging carrier SURFACTANT Condensation nucleus material
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Intrinsic thermal stability of inverted perovskite solar cells based on electrochemical deposited PEDOT 被引量:2
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作者 Congtan Zhu Jing Gao +2 位作者 Tian Chen Xueyi Guo Ying Yang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第8期445-453,I0011,共10页
Thermal stability of perovskite materials is an issue impairing the long-term operation of inverted perovskite solar cells(PSCs). Herein, the thermal attenuation mechanism of the MAPb I3films that deposited on two dif... Thermal stability of perovskite materials is an issue impairing the long-term operation of inverted perovskite solar cells(PSCs). Herein, the thermal attenuation mechanism of the MAPb I3films that deposited on two different hole transport layers(HTL), poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate)(PEDOT:PSS) and poly(3,4-ethylenedioxythiophene)(PEDOT), is comprehensively studied by applying a heat treatment at 85℃. The thermal stress causes the mutual ions migration of I, Pb and Ag through the device, which leads to the thermal decomposition of perovskite to form Pb I2. Interestingly, we find that I ions tend to migrate more towards electron transport layer(ETL) during heating, which is different with the observation of I ions migration towards HTL when bias pressure is applied. Moreover, the use of electrochemical deposited PEDOT as HTL significantly decreases the defect density of MAPb I3films as compared to PEDOT:PSS supported one. The electrochemical deposition PEDOT has good carrier mobility and low acidity, which avoids the drawbacks of aqueous PEDOT:PSS. Accordingly, the inverted PSCs based on PEDOT show superior durability than that with PEDOT:PSS. Our results reveal detailed degradation routes of a new kind of inverted PSCs which can contribute to the understanding of the failure of thermal-aged inverted PSCs. 展开更多
关键词 Inverted perovskite solarcells CH_(3)NH_(3)Pbl_(3) thermal stability Electrochemical deposition PEDOT
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Experimental study on thermal and mechanical properties of tailings-based cemented paste backfill with CaCl_(2)·6H_(2)O/expanded vermiculite shape stabilized phase change materials 被引量:2
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作者 Xiaoyan Zhang Tianrun Cao +3 位作者 Lang Liu Baoyun Bu Yaping Ke Qiangqiang Du 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2023年第2期250-259,共10页
CaCl_(2)·6H_(2)O/expanded vermiculite shape stabilized phase change materials(CEV)was prepared by atmospheric impregnation method.Using gold mine tailings as aggregate of cemented paste backfill(CPB)material,the ... CaCl_(2)·6H_(2)O/expanded vermiculite shape stabilized phase change materials(CEV)was prepared by atmospheric impregnation method.Using gold mine tailings as aggregate of cemented paste backfill(CPB)material,the CPB with CEV added was prepared,and the specific heat capacity,thermal conductivity,and uniaxial compressive strength(UCS)of CPB with different cement-tailing ratios and CEV addition ratios were tested,the influence of the above variables on the thermal and mechanical properties of CPB was analyzed.The results show that the maximum encapsulation capacity of expanded vermiculite for CaCl_(2)·6H_(2)O is about 60%,and the melting and solidification enthalpies of CEV can reach 98.87 J/g and 97.56 J/g,respectively.For the CPB without CEV,the specific heat capacity,thermal conductivity,and UCS decrease with the decrease of cement-tailing ratio.For the CPB with CEV added,with the increase of CEV addition ratio,the specific heat capacity increases significantly,and the sensible heat storage capacity and latent heat storage capacity can be increased by at least 10.74%and 218.97%respectively after adding 12%CEV.However,the addition of CEV leads to the increase of pores,and the thermal conductivity and UCS both decrease with the increase of CEV addition.When cement-tailing ratio is 1:8 and 6%,9%,and 12%of CEV are added,the 28-days UCS of CPB is less than 1 MPa.Considering the heat storage capacity and cost price of backfill,the recommended proportion scheme of CPB material presents cement-tailing ratio of 1:6 and 12%CEV,and the most recommended heat storage/release temperature cycle range of CPB with added CEV is from 20 to 40℃.This work can provide theoretical basis for the utilization of heat storage backfill in green mines. 展开更多
关键词 CaCl_(2)·6H_(2)O/expanded vermiculite shape stabilized phase change materials cemented paste backfill thermal property mechanical property
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Thermal–moisture dynamics and thermal stability of active layer in response to wet/dry conditions in the central region of the Qinghai–Tibet Plateau,China 被引量:1
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作者 MingLi Zhang ZhiXiong Zhou +3 位作者 Zhi Wen FengXi Zhou Zhao Ma BingBing Lei 《Research in Cold and Arid Regions》 CSCD 2023年第1期27-38,共12页
The amount of rainfall varies unevenly in different regions of the Qinghai-Tibet Plateau, with some regions becoming wetter and others drier. Precipitation has an important impact on the process of surface energy bala... The amount of rainfall varies unevenly in different regions of the Qinghai-Tibet Plateau, with some regions becoming wetter and others drier. Precipitation has an important impact on the process of surface energy balance and the energy-water transfer within soils. To clarify the thermal-moisture dynamics and thermal stability of the active layer in permafrost regions under wet/dry conditions, the verified water-vapour-heat coupling model was used. Changes in the surface energy balance, energy-water transfer within the soil, and thickness of the active layer were quantitatively analyzed. The results demonstrate that rainfall changes significantly affect the Bowen ratio, which in turn affects surface energy exchange. Under wet/dry conditions, there is a positive correlation between rainfall and liquid water flux under the hydraulic gradient;water vapour migration is the main form under the temperature gradient, which indicates that the influence of water vapour migration on thermalmoisture dynamics of the active layer cannot be neglected. Concurrently, regardless of wet or dry conditions,disturbance of the heat transport by conduction caused by rainfall is stronger than that of convection by liquid water. In addition, when rainfall decreases by 1.5 times(212 mm) and increases by 1.5 times(477 mm), the thickness of the active layer increases by 0.12 m and decreases by 0.21 m, respectively. The results show that dry conditions are not conducive to the preservation of frozen soil;however, wet conditions are conducive to the preservation of frozen soil, although there is a threshold value. When this threshold value is exceeded, rainfall is unfavourable for the development of frozen soil. 展开更多
关键词 Active layer Wet/dry conditions Qinghai-Tibet Plateau(QTP) thermal-moisture dynamics Permafrost thermal stability Numerical modelling
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Rare Earth Stearates as Thermal Stabilizers for Rigid Poly(vinyl chloride) 被引量:16
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作者 郑玉婴 蔡伟龙 +2 位作者 傅明连 王灿耀 张星 《Journal of Rare Earths》 SCIE EI CAS CSCD 2005年第2期172-177,共6页
A series of stearates with different rare-earth ion were investigated as thermal stabilizers for rigid PVC at 180 ℃ in air. Their stabilizing efficiency was based on measuring the rate of dehydrochlorination. The res... A series of stearates with different rare-earth ion were investigated as thermal stabilizers for rigid PVC at 180 ℃ in air. Their stabilizing efficiency was based on measuring the rate of dehydrochlorination. The resulted revealed the higher stabilizing efficiency of the investigated rare-earth stearates as thermal stabilizers for rigid PVC compared with the thermal stabilizers for industry: calcium stearate, zinc stearate, butyl stannum mercaptide, phosphite esters, β-diketone and epoxidized sunflower oil. This was well illustrated by longer incubation period (T_S) values and lower rate of dehydrochlorination. The stable efficiency was affected by the nature of rare-earth element's individual electronic shell. The mechanism for the stabilizing effect of rare-earth stearates was proposed. The result was experimentally proved based on IR spectrum. 展开更多
关键词 poly(vinyl chloride) thermal dehydrochlorination rare-earth stearates stabilization mechanism conductivity method congo red test
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Optimizing the morphology of all-polymer solar cells for enhanced photovoltaic performance and thermal stability
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作者 Kang An Wenkai Zhong +8 位作者 Chunguang Zhu Feng Peng Lei Xu Zhiwei Lin Lei Wang Cheng Zhou Lei Ying Ning Li Fei Huang 《Journal of Semiconductors》 EI CAS CSCD 2023年第5期34-41,共8页
Due to the complicated film formation kinetics, morphology control remains a major challenge for the development of efficient and stable all-polymer solar cells(all-PSCs). To overcome this obstacle, the sequential dep... Due to the complicated film formation kinetics, morphology control remains a major challenge for the development of efficient and stable all-polymer solar cells(all-PSCs). To overcome this obstacle, the sequential deposition method is used to fabricate the photoactive layers of all-PSCs comprising a polymer donor PTzBI-oF and a polymer acceptor PS1. The film morphology can be manipulated by incorporating amounts of a dibenzyl ether additive into the PS1 layer. Detailed morphology investigations by grazing incidence wide-angle X-ray scattering and a transmission electron microscope reveal that the combination merits of sequential deposition and DBE additive can render favorable crystalline properties as well as phase separation for PTzBI-oF:PS1 blends. Consequently, the optimized all-PSCs delivered an enhanced power conversion efficiency(PCE) of 15.21%along with improved carrier extraction and suppressed charge recombination. More importantly, the optimized all-PSCs remain over 90% of their initial PCEs under continuous thermal stress at 65 °C for over 500 h. This work validates that control over microstructure morphology via a sequential deposition process is a promising strategy for fabricating highly efficient and stable all-PSCs. 展开更多
关键词 MORPHOLOGY all-polymer solar cells thermal stability sequential deposition
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Stability and Thermal Property Optimization of Propylene Glycol-Based MWCNT Nanofluids
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作者 Xi Wang Shan Qing +3 位作者 Zhumei Luo Yiqin Liu Zichang Shi Jiachen Li 《Fluid Dynamics & Materials Processing》 EI 2023年第9期2399-2416,共18页
Propylene glycol-based MWCNT(multi-walled carbon nanotubes)nanofluids were prepared in the framework of a two-step method and by using a suitable PVP(polyvinyl pyrrolidone)dispersant.The BBD(Box-Behnken design)model wa... Propylene glycol-based MWCNT(multi-walled carbon nanotubes)nanofluids were prepared in the framework of a two-step method and by using a suitable PVP(polyvinyl pyrrolidone)dispersant.The BBD(Box-Behnken design)model was exploited to analyze 17 sets of experiments and examine the sensitivity of the absorbance to three parameters,namely the concentration of MWCNT,the SN ratio(mass ratio of carbon nanotubes to sur-factants)and the sonication time.The results have revealed that,while the SN ratio and concentration of MWCNT have a strong effect on the absorbance,the influence of the sonication time is less important.The sta-tistical method of analysis of variance(ANOVA)was further used to determine the F-and p-values of the model.Five experiments were run to validate this approach.Since sample 2 was found to display the greatest absorbance,it was selected for stability monitoring as well as thermal conductivity and viscosity measurements.This sample has been found to be stable;the viscosity decreased with increasing temperature;the addition of MWCNT nano-particles was more effective in improving the thermal conductivity of propylene glycol than other methods in the literature.Moreover,the MWCNT nanofluid based on propylene glycol exhibited higher thermal conductivity at low temperatures. 展开更多
关键词 Propylene glycol thermal conductivity response surface methodology stabilITY VISCOSITY
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17.13% Efficiency and Superior Thermal Stability of Organic Solar Cells Based on a Comb-Shape Active Blend
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作者 Zhipeng Yin Qingjie Wang +3 位作者 Huan Zhao Haiqiao Wang Ning Li Weijie Song 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2023年第6期266-272,共7页
With rapid progress,organic solar cells(OSCs)are getting closer to the target of real application.However,the stability issue is still one of the biggest challenges that have to be resolved.Especially,the thermal stab... With rapid progress,organic solar cells(OSCs)are getting closer to the target of real application.However,the stability issue is still one of the biggest challenges that have to be resolved.Especially,the thermal stability of OSCs is far from meeting the requirements of the application.Here,based on the layer-by-layer(LBL)process and by utilizing the dissolubility nature of solvent and materials,binary inverted OSCs(ITO/AZO/PM6/BTP-eC9/MoO3/Ag)with comb shape active morphology are fabricated.High efficiency of 17.13%and simultaneous superior thermal stability(with 93%of initial efficiency retained in~9:00 h under 85℃in N_(2))are demonstrated,showing superior stability to reference cells.The enhancements are attributed to the formed optimal comb shape of the active layer,which could provide a larger D/A interface,thus more charge carriers,render the active blend a more stable morphology,and protect the electrode by impeding ion's migration and corrosion.To the best of our knowledge,this is the best thermal stability of binary OSCs reported in the literature,especially when considering the high efficiency of over 17%. 展开更多
关键词 comb-shape blend high efficiency organic solar cell thermal stability
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Exceptional thermal stability and enhanced hardness in a nanostructured Mg-Gd-Y-Zn-Zr alloy processed by high pressure torsion
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作者 Wanting Sun Yang He +5 位作者 Xiaoguang Qiao Xiaojun Zhao Houwen Chen Nong Gao Marco J.Starink Mingyi Zheng 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2023年第12期4589-4602,共14页
A Mg-8.2Gd-3.8Y-1.0Zn-0.4Zr(wt.%) alloy is processed by solution treatment and high pressure torsion(HPT) at room temperature to produce a nanostructured light material with high hardness. The stability of this alloy ... A Mg-8.2Gd-3.8Y-1.0Zn-0.4Zr(wt.%) alloy is processed by solution treatment and high pressure torsion(HPT) at room temperature to produce a nanostructured light material with high hardness. The stability of this alloy is subsequently tested through isochronal annealing for 0.5 h at 373 K to 673 K. The results reveal a thermal stability that is vastly superior to that of conventional Mg-based alloys processed by severe plastic deformation: the grain size remains at around 50 nm on heating to 573 K, and as the temperature is increased to 673 K,grain growth is restricted to within 500 nm. The stability of grain refinement of the present alloy/processing combination allowing grain size to be limited to 55 nm after exposure at 573 K, appears to be nearly one order of magnitude better than for the other SPD processed Mg-RE type alloys, and 2 orders of magnitude better than those of SPD processed RE-free Mg alloys. This superior thermal stability is attributed to formation of co-clusters near and segregation at grain boundaries, which cause a thermodynamic stabilization of grain size, as well as formation of β-Mg_(5)RE equilibrium phase at grain boundaries, which impede grain growth by the Zener pinning effect. The hardness of the nanostructured Mg-Gd-Y-Zn-Zr alloy increases with increasing annealing temperature up to 573 K, which is quite different from the other SPD-processed Mg-based alloys. The high hardness of 136 HV after annealing at 573 K is mainly due to solute segregation and solute clustering at or near grain boundaries. 展开更多
关键词 Mg-RE alloy High pressure torsion thermal stability Grain growth Solute segregation Phase transformation
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Thermal stability analysis of a satellite-borne optical bench based on quasi-kinematic support
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作者 Huan Zhang ChunYu Yu +3 位作者 Le Suo WenBo Luo Ding Yuan JiaMing Ou 《Earth and Planetary Physics》 EI CSCD 2023年第1期119-124,共6页
Macao Science Satellite-1(known as MSS-1)is a low-inclination mission that will be launched at the beginning of 2023.An optical bench is used for accessing high-precision strength and direction measurements of the mag... Macao Science Satellite-1(known as MSS-1)is a low-inclination mission that will be launched at the beginning of 2023.An optical bench is used for accessing high-precision strength and direction measurements of the magnetic field.In this paper,we present a thermal stability design for the optical bench based on quasi-kinematic support by kinematic hinges on the MSS-1.The change in angles with the finite element method(FEM)model modified by thermal deformation test data is analyzed.The robustness of the structure is also investigated via the Monte Carlo method.Two main results are obtained.First,the peak-to-peak value(Vp-p)of the inter-boresight angle is at most 1.24″,and the Vp-p of the inter-boresight angle modification and analysis is no more than 3.13″,both of which are better than those on the Swarm satellites in orbit.Second,the 90°fibers of the carbon-reinforced arm need to be strictly controlled during the technological process. 展开更多
关键词 thermal stability finite element method Monte Carlo
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Efficient Thermal Stabilization of Polyvinyl Chloride with Tannin-Ca Complex as Bio-Based Thermal Stabilizer 被引量:1
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作者 Hussein A. Shnawa Moayad N. Khalaf +1 位作者 Yousef Jahani Abed Alameer H. Taobi 《Materials Sciences and Applications》 2015年第5期360-372,共13页
The potential use of tannin-Ca complex derived from tannins as bio-based thermal stabilizer and antioxidant additive for polyvinyl chloride (PVC) was investigated in this work. For this project, Reapak B-NT/7060 was a... The potential use of tannin-Ca complex derived from tannins as bio-based thermal stabilizer and antioxidant additive for polyvinyl chloride (PVC) was investigated in this work. For this project, Reapak B-NT/7060 was applied as reference thermal stabilizer. Variable compositions: (1, 2, and 3) part per hundred ratio (phr) of tannin-Ca complex in the presence of 10 phr Dioctyl phthalate (DOP) as plasticizer in all PVC formulations were prepared by melt mixing by internal mixer at 165°C. Tannin-Ca complex was characterized by FT-IR spectroscopy, scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDX) analysis as well as by means of differential scanning calorimetry (DSC). The tannin derivative stabilization efficiency under inert atmosphere was determined by using thermogravimetric analysis (TGA). In addition, its thermal stabilization effect has been assessed in air as oxidizing atmosphere by DSC in dynamic conditions. According to TGA thermograms, the initial degradation temperature (Ti) and optimum degradation temperature (Top?) for the main degradation stage of PVC stabilized with this derivative were about 280°C and 310°C, respectively. While these were about 255°C and 293°C, respectively for PVC stabilized with commercial thermal stabilizer. Global results of TGA, DSC, SEM and EDX show that the tannin-Ca complex provides the best properties and results in stabilizing both against thermal degradation and thermal oxidation degradation of PVC. 展开更多
关键词 PVC Natural POLYPHENOLS Tannin-Calcium COMPLEX Bio-Based thermal stabilizer
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Effect of Polyethylene Terephthalate Plastic Waste on the Physico-Mechanical and Thermal Characteristics of Stabilized Laterite Bricks
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作者 Aboubacar Sidiki Toure Moussa Tamboura +4 位作者 Antoine Padou Diarra Adama Coulibaly Dodo Kayentao Kélétigui Daou Mah Fatoumata Traore 《Open Journal of Applied Sciences》 2023年第6期910-920,共11页
The present work investigated the effect of polyethylene terephthalate (PET) plastic waste on the physico-mechanical and thermal properties of cement-stabilized laterite bricks to see the durability of the modified br... The present work investigated the effect of polyethylene terephthalate (PET) plastic waste on the physico-mechanical and thermal properties of cement-stabilized laterite bricks to see the durability of the modified bricks (CSLB). Samples were formulated by mixing laterite, cement, and different percentages of PET (0%, 3%, 5%, and 7%) by volume. The bricks were produced using the M7MI Hydraform standard interlocking block and kept in the shade for a curing period of 28 days. The addition of 3% to 5% PET to the laterite stabilized with 10% cement results in a decrease in both dry and wet compressive strength, which is determined using the Controlab compression machine. However, the obtained results are in concordance with the standards. The thermal conductivity of CSLB, determined using the box method with the EI700 measurement cell, decreases as the PET content of the mixture increases. A decrease in bulk density from 1.67 to 1.58 g/cm<sup>3</sup> was observed. 展开更多
关键词 Plastic Waste Polyethylene Terephthalate Laterite Bricks Cement stabilization thermal Conductivity
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