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Solution combustion synthesis of high-entropy rare earth oxide Ce_(0.2)La_(0.2)Gd_(0.2)Y_(0.2)Lu_(0.2)O_(1.6):xEu^(3+) phosphor with intense blue-light excitable red emission for solid-state lighting

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Journal of Advanced Ceramics 2024年第11期13卷 1852-1860页

作者： Ziqing Yin yufeng mao Shikao Shi Jiye Wang Ruilong Zong College of Chemistry and Materials Science Hebei Key Laboratory of Inorganic NanomaterialsHebei Normal UniversityShijiazhuang 050024China Department of Chemistry Tsinghua UniversityBeijing 100084China

Red-light-emitting phosphors capable of being well excited with blue light are highly desirable in solid-state *** this work,a novel Eu^(3+)-activated high-entropy rare earth oxide Ce_(0.2)La_(0.2)Gd_(0.2)Y_(0.2)Lu_(0.2)O_(1.6):xEu^(3+)(x=4–16 mol%)phosphor was successfully prepared by solution combustion reaction for the first *** multi-composition rare earth oxide has a specific cubic fluorite structure,which is almost the same as that of the pure CeO_(2) despite the tiny ceria composition in the sample,demonstrating the formation of a high-entropy composite solid *** our surprise,the high-entropy phosphor exhibits extremely intense red emission at 613 nm,corresponding to the 5D0→7F2 characteristic transition of Eu^(3+)under the excitation of blue light at 466 *** luminescence internal quantum yield(QY)for the optimal high-entropy phosphor(x=12 mol%)reaches nearly 50%and can further increase to 67.8%through a subsequent heat-treatment process at 1400°*** QY result is much superior to that of previously reported Eu^(3+)-activated CeO_(2) as well as Y2Ce2O7 and La2Ce2O7 low-entropy composite oxides(QYs are approximately 10%–20%).Moreover,the high-entropy oxide phosphor also shows better luminescence thermal stability than low-entropy oxides,as confirmed from the temperature-dependent photoluminescence emission *** tremendous improvement in optical properties depends closely upon the high-entropy and other related *** novel high-entropy rare earth oxide phosphor is beneficial to be used in the field of solid-state lighting owing to the coincidence of excitation of blue light with the emission of InGaN light-emitting diode(LED)chips.

关键词： high-entropy oxide rare earth red phosphor solid-state lighting

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A nano-sheet graphene-based enhanced thermal radiation composite for passive heat dissipation from vehicle batteries

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Nano Materials Science 2024年第4期6卷 443-455页

作者： Ji-Xiang Wang Christopher Salmean Jiaxin Li Chaojie Lei Jun Li Mingliang Zhong Bo Qi yufeng mao Hebei Key Laboratory of Man-machine Environmental Thermal Control Technology and Equipment Hebei Vocational University of Technology and EngineeringHebei 054000PR China College of Electrical Energy and Power EngineeringYangzhou UniversityYangzhou225009PR China Department of Mechanical and Aerospace Engineering The Hong Kong University of Science and TechnologyKowloonHong Kong SARPR China China Academy of Launch Vehicle Technology Beijing100076PR China Beijing Sino-Spark Technology Co. Ltd.Beijing100191PR China School of Environmental Science and Engineering Suzhou University of Science and TechnologySuzhou215009PR China Institute of Optics and Electronics Chinese Academy of SciencesChengdu610209PR China National Key Laboratory of Optical Field Manipulation Science and Technology Chinese Academy of SciencesChengdu610209PR China Taizhou Wavexploration Energy Ltd. Taizhou225513PR China Department of Electrical and Computer Engineering University of TorontoTorontoM5S3G4Canada

In response to thermal runaway(TR)of electric vehicles,recent attention has been focused on mitigation strategies such as efficient heat dredging in battery thermal *** management with particular focus on battery cooling has been becoming increasingly *** usually happened when an electric vehicle is unpowered and *** this state,traditional active battery cooling schemes are disabled,which can easily lead to dangerous incidents due to loss of cooling ability,and advanced passive cooling strategies are therefore gaining ***,we developed an enhanced thermal radiation material,consisting of~1μm thick multilayered nano-sheet graphene film coated upon the heat dissipation surface,thereby enhancing thermal radiation in the *** surface was characterized on the nanoscale,and tested in a battery-cooling *** found that the graphene-based coating's spectral emissivity is between 91% and 95% in the mid-infrared region,and thermal experiments consequently illustrated that graphene-based radiative cooling yielded up to15.1% temperature reduction when compared to the uncoated *** the novel graphene surface to augment a heat pipe,the temperature reduction can be further enlarged to 25.6%.The new material may contribute to transportation safety,global warming mitigation and carbon neutralization.

关键词： Battery thermal management Nano-sheet graphene Functional material Passive cooling Thermal radiation

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Book Review of History of Huizu in China

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Asian Journal of Middle Eastern and Islamic Studies 2007年第1期1卷 80-80,I0008页

作者： yufeng mao ashington University in St.Louis

Shusen Qiu,et ***.,Zhongguo Huizu Shi(History of Huizu in China),2 Volumes,Yinchuan:Ningxia Renmin Chubanshe,*** product of collaboration by ten leading Chinese scholars,these two volumes represent the encyclopedic work on the history of Chinese *** to the work of authors such as Shusen Qiu,who specializes in Muslim history during the Yuan Dynasty,this work is particularly detailed in recounting the development of Muslim communities prior to the more familiar Ming-Qing and modern periods.

关键词： History Ningxia collaboration

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Tactile Paving Recognition Method Based on Improved YOLOv7

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Journal of Electronic Research and Application 2024年第4期8卷 22-27页

作者： Chengyi Shi Qun Zhao Nan Fang yufeng mao School of Computer Engineering Nanjing Institute of TechnologyNanjing 211167China NR Electric Co. Ltd.Nanjing 211102China

Tactile paving is a professional road facility to ensure the safe travel of people with visual ***,there are many problems with tactile paving travel in *** one,some tactile paving is seriously damaged,and the other is the accumulation of *** to help visually impaired people recognize and locate obstacles in tactile paving is a problem worth *** this paper,image recognition technology is used to recognize the tactile paving pictures with obstacles,and an attention mechanism is used to optimize samples to improve recognition accuracy.

关键词： YOLOv7 Tactile paving recognition Attention mechanism

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Pollution Characteristics and Health Risk Assessment of Heavy Metals in PM_2.5 during Winter in the Suburb of Cangzhou, China

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Journal of Geoscience and Environment Protection 2022年第8期10卷 122-136页

作者： Jian Wang Zhenxia Chen Yaheng Pang Yanan Zhao yufeng mao Na mao Mei Xu College of Chemistry and Chemical Engineering Cangzhou Normal University Cangzhou China Cangzhou Municipal Research Institute of Environmental Protection Cangzhou China

The heavy metals in atmospheric fine particles are of great concern to human health. To understand the pollution characteristics and health risks of heavy metals in particulate matter with an aerodynamic equivalent diameter ≤2.5 μm (PM2.5) during winter in the suburb of Cangzhou, PM2.5 samples were collected with an intelligent medium-flow atmospheric particulate matter sampler from January to February 2019. The Fe, Cu, Mn, Pb and Zn contents in PM2.5 were determined via inductively coupled plasma optical emission spectrometry (ICP-OES). The sources and health risks of heavy metals in PM2.5 were analysed via the enrichment factor (EF) method and the United States Environmental Protection Agency (US EPA) health risk assessment model. The results showed that the average PM2.5 concentration in the suburb of Cangzhou reached 71.6 μg/m3, ranging from 23.7 to 169.5 μg/m3. The exceeding standard rate was 29.4% during the sampling period. The PM2.5 concentration during the nighttime was higher than that during the daytime. The heavy metal concentrations in PM2.5 decreased in the order of Fe > Mn > Zn > Cu > Pb, and the Fe, Mn, Pb and Zn concentrations decreased in the order of clean days < pollution days < heavy pollution days. The Fe and Mn concentrations were higher during the daytime than those during the nighttime, while the Cu, Pb and Zn concentrations were higher during the nighttime than those during the daytime. EF analysis revealed that Zn, Pb and Cu were significantly enriched, and Pb was highly enriched on heavy pollution days with increasing pollution degree. The enrichment level of heavy metals during the nighttime was higher than that during the daytime. Health risk assessment demonstrated that Mn posed non-carcinogenic risks to both adults and children, following the sequence of clean days < pollution days < heavy pollution days. Pb posed a carcinogenic risk to

关键词： Fine Particles Enrichment Factor Atmospheric Pollution Different Pollution Levels

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新媒体背景下高校突发事件网络舆情传播模式及应对

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江苏高教 2020年第6期 67-70页

作者：毛宇锋绍兴文理学院对外联络处浙江绍兴312000

在微博、微信等新媒体主导互联网舆论生成的背景下,高校突发事件网络舆情呈现新变化。由于高校突发事件网络舆情传播主体间的特殊关系,呈现出由"强关系"向"弱关系"演进的传播模式,并且"强关系"和"弱关系"在舆情萌芽、关注、爆发、消退... 详细信息

在微博、微信等新媒体主导互联网舆论生成的背景下,高校突发事件网络舆情呈现新变化。由于高校突发事件网络舆情传播主体间的特殊关系,呈现出由"强关系"向"弱关系"演进的传播模式,并且"强关系"和"弱关系"在舆情萌芽、关注、爆发、消退各个阶段发挥着不同的作用。根据传播模式要注重"声誉管理"、构建监控体系、及时干预处置,从而最大程度上预防或减少突发事件网络舆情对高校及社会带来的影响。

关键词：新媒体高校突发事件网络舆情国家突发公共事件

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高超声速飞机热管理系统控制模型构建与仿真

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航空动力学报 2018年第3期33卷 741-751页

作者：于喜奎毛羽丰中国航空工业集团有限公司沈阳飞机设计研究所沈阳110035 北京航空航天大学航空科学与工程学院北京100191

以高超声速飞机为研究对象,提出了一种基于单相流体回路的热管理系统(TMS)模型,通过热控制策略与热沉调度模型实现热沉制冷能力最大化目标,解决新型高速飞机日益彰显的冷源不足问题。热控制策略利用系统辨识与热载荷预测算法,提出基于... 详细信息

以高超声速飞机为研究对象,提出了一种基于单相流体回路的热管理系统(TMS)模型,通过热控制策略与热沉调度模型实现热沉制冷能力最大化目标,解决新型高速飞机日益彰显的冷源不足问题。热控制策略利用系统辨识与热载荷预测算法,提出基于能量平衡与温度反馈配合的热控制模型,解决热惯性带来的控制延迟问题。基于热沉冷却能力评估与热载荷匹配提出热沉调度模型,旨在合理利用各种冷源,解决飞行后期冷源不足的问题。研究通过MATLAB/Simulink仿真验证模型及算法,结果表明:所设计的TMS能够满足高超声速飞机长时间飞行需求;考虑能量平衡的控制模型在超调量及衰减比方面均优于温度反馈控制模型;基于热沉调度策略能够降低冷源消耗速率,更充分地利用各种机载热沉。

关键词：高超声速热管理系统热沉热控制热载荷

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芝麻乙醇提取物对运动性疲劳大鼠心肌损伤的保护效应及其作用机制研究

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中国食品卫生杂志 2023年第2期35卷 156-162页

作者：李强毛羽丰西北政法大学体育系陕西西安710122 陕西师范大学食品工程与营养科学学院陕西西安710119

目的研究芝麻乙醇提取物(SEE)对运动性疲劳(EIF)大鼠的心脏保护作用及其对心肌生理生化指标的影响。方法将大鼠随机分为对照组(Control)、EIF组、EIF+0.5SEE组、EIF+1SEE组和EIF+2SEE组,每组12只。对照组和EIF组大鼠连续14 d每天灌胃2 m... 详细信息

目的研究芝麻乙醇提取物(SEE)对运动性疲劳(EIF)大鼠的心脏保护作用及其对心肌生理生化指标的影响。方法将大鼠随机分为对照组(Control)、EIF组、EIF+0.5SEE组、EIF+1SEE组和EIF+2SEE组,每组12只。对照组和EIF组大鼠连续14 d每天灌胃2 mL纯净水。EIF+0.5SEE组、EIF+1SEE组和EIF+2SEE组大鼠连续14 d每天分别灌胃0.5、1.0和2.0 g/kg·BW的SEE。通过跑步机运动建立EIF大鼠模型。运动后,检测各组大鼠的超声心动图参数(LVPWd、LVPWs、LVIDs、EF和FS)、血清心肌损伤指标(LDH、CK和cTnI)和心肌组织抗氧化指标(MDA、SOD、CAT和GSH-Px)。通过苏木精和伊红(HE)染色检测心肌形态。利用免疫印迹检测心肌组织中缝隙连接蛋白43(Cx43)、ATP 5D、磷酸化的AMP依赖的蛋白激酶(p-AMPK)和AMPK的蛋白表达。结果与EIF组比较,EIF+0.5SEE组、EIF+1SEE组和EIF+2SEE组的LVPWd、LVPWs和LVIDs均显著降低,而EF和FS均显著升高(P<0.05)。与EIF组比较,EIF+0.5SEE组、EIF+1SEE组和EIF+2SEE组心肌损伤明显减轻,血清LDH、CK和cTnI水平均显著降低(P<0.05)。与EIF组比较,EIF+0.5SEE组、EIF+1SEE组和EIF+2SEE组的心肌组织MDA含量均显著降低,而SOD、CAT和GSH-Px活性均显著升高(P<0.05)。与EIF组比较,EIF+0.5SEE组、EIF+1SEE组和EIF+2SEE组的心肌组织Cx43、ATP 5D和p-AMPK/AMPK蛋白表达水平均显著升高(P<0.05)。结论SEE有效预防了EIF大鼠的心肌损伤并改善了心脏功能,SEE可能通过改善心肌组织中的抗氧化系统、缝隙连接、能量代谢和线粒体生物发生来发挥心脏保护作用。

关键词：芝麻乙醇提取物运动性疲劳抗氧化缝隙连接能量代谢线粒体生物发生

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