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Wall-Attached Night Ventilation Combined with Phase Change Material Wallboard in Hot Summer:An Experimental Study on the Thermal Performance

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Journal of Thermal Science 2022年第2期31卷 318-331页

作者： JI Wenhui YUAN Yanping li yajun YU Min School of Mechanical Engineering Southwest Jiaotong UniversityChengdu 610031China

Night ventilation is regarded as a promising cooling strategy by storing night cooling in the thermal mass of the building.However,night ventilation performance in hot summer is restricted by the climatic limits.In this paper,we propose a new solution as the integration of wall-attached night ventilation(WANV)and phase change material wallboard(PCMW).The principle of the proposed system is to utilize the wall-attached jet ventilation to achieve forced convection and to adopt latent energy storage of PCMW to enlarge the energy storage density capabilities,and the coupling method is expected to improve the night ventilation performance.Comparative experiments were conducted to evaluate the thermal performance of the hybrid system by evaluating indoor temperature history,thermal comfort time and cooling efficiency.Due to the high thermal energy storage density capability of PCMW,it was found that the presence of PCMW has a negative influence on night cooling efficiency but still has a positive influence on the overall cooling effect.The proposed WANV combined with the PCMW system significantly increased the temperature decrease of room air and west wall inside surface during one hour's night ventilation by 94.97%and 67.74%,respectively,and reached an extension of 38.42%of indoor thermal comfort time.The results highlight the potential of WANV integration of PCMW to improve the thermal performance of night ventilation.

关键词： night ventilation wall-attached jet ventilation phase change material wallboard thermal performance

The Transfer and Change of Paints in a Hit-and-run Motor Vehicle Accident

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Journal of Forensic Science and Medicine 2024年第1期10卷 24-27页

作者： Can Hu Jun Zhu Hongcheng Mei Hongling Guo Ping Wang yajun li Trace Evidence Department Institute of Forensic ScienceMinistry of Public SecurityXichengBeijingChina

This work investigated transfer and change of paint evidences in a case of hit-and-run.Two kinds of attachments were found on the clothes of the victim and they were initially considered paint fragments from the vehicle causing the accident.Infrared spectroscopy(IR),scanning electron microscope-energy dispersive spectrometer,and Microspectrophotometry were applied for examination of paints and clothing fibers.Polyester was detected in one of the attachments and in the clothing fibers of the victim by IR.A traffic accident simulation experiment was designed and conducted to research whether the polyester attachments come from suspected vehicle paints or victim’s clothing fibers.The results showed that a melt mixture of transferred paints and clothing fiber was formed after a violent collision.Because the amount of transferred paints was too low to be detectable in the mixture,the components detected by IR were mainly from clothing fibers.Thereby,we inferred that only one kind of attachment and paint fragments existed on the clothes of the victim,and the polyester attachments cannot be used to indicate the composition of suspected vehicle paint.Clothing fibers and paints are both common trace evidence in traffic accident cases,and more attention should be paid to the examination of transferred paints on clothing fibers.

关键词： Clothing fibers hit‑and‑run traffic accident infrared spectroscopy paints trace evidence transfer

Integration of LNG Regasification Process in Natural Gas-Fired Power System with Oxy-Fuel Combustion

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Journal of Thermal Science 2022年第5期31卷 1351-1366页

作者： liU Rong XIONG Yongqiang KE liying liANG Jiacheng CHEN Dengjie ZHAO Zhongxing li yajun College of Chemistry and Materials Science Ji’nan UniversityGuangzhou510632China Guangxi Key Laboratory of Petrochemical Resource Processing and Process Intensification Technology Guangxi UniversityNanning530004China Key Lab of Heat Transfer Enhancement and Energy Conservation of the Ministry of Education South China University of TechnologyGuangzhou510640China

Oxy-fuel combustion power systems can utilize the cold energy released during the liquefied natural gas(LNG)regasification to reduce the power consumption of CO_(2) capture,but the specific LNG cold energy consumption of CO_(2) capture is still too large.To recover more CO_(2) with the limited LNG cold energy at a low energy cost,a novel natural gas-fired oxy-fuel power system with the cascade utilization of LNG cold energy is proposed in this work,where the LNG cold energy could be sequentially utilized in the air separation unit and the CO_(2) recovery process.The new system is evaluated with the Aspen Plus software.The results show that the net electrical efficiency and the specific primary energy consumption for CO_(2) avoided(SPECCA)of the new system are comparable to those of the chemical looping combustion cycle,and superior to those of the conventional O_(2)/CO_(2) cycles.Moreover,the specific LNG needed for CO_(2) avoided(SLNCC)of the new system is more than 67.2%lower than the existing oxy-fuel power systems utilizing the LNG cold energy.Furthermore,it is found that the O_(2) purity of 97.0 mol.%and the CO_(2) capture ratio of 97.0%are optimal conditions,because the SPECCA,the specific exergy consumption for CO_(2) avoided(SECCA)and the SLNCC are at the minimum of 1.87 GJLHV⋅t_(CO_(2))^(−1),2.60GJ⋅t_(CO_(2))^(−1) and 1.88tLNG⋅t_(CO_(2))^(−1),respectively.Meanwhile,the net electrical efficiency and the exergy efficiency of the new system reach 51.51%and 49.23%,respectively.

关键词： oxy-fuel combustion CO_(2)capture LNG cold energy efficiency

An approach of motion compensation and ISAR imaging for micro-motion targets

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Journal of Systems Engineering and Electronics 2021年第1期32卷 68-80页

作者： WANG Yong ZHOU Xingyu LU Xiaofei li yajun School of Electronics and Information Engineering Harbin Institute of TechnologyHarbin 150001China Jiuquan Satellite Launch Center Jiuquan 732750China Shanghai Radio Equipment Research Institute Shanghai 201109China

Inverse synthetic aperture radar(ISAR)imaging of the target with the non-rigid body is very important in the field of radar signal processing.In this paper,a motion compensation method combined with the preprocessing and global technique is proposed to reduce the influence of micro-motion components in the fast time domain,and the micro-Doppler(m-D)signal in the slow time domain is separated by the improved complex-valued empirical-mode decomposition(CEMD)algorithm,which makes the m-D signal more effectively distinguishable from the signal for the main body by translating the target to the Doppler center.Then,a better focused ISAR image of the target with the non-rigid body can be obtained consequently.Results of the simulated and raw data demonstrate the effectiveness of the algorithm.

关键词： inverse synthetic aperture radar(ISAR) micro-Doppler(m-D) motion compensation complex-valued empiricalmode decomposition(CEMD)

人参皂苷Rc通过调控AMPK通路介导的细胞焦亡减轻小鼠脑缺血再灌注损伤

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中国病理生理杂志 2024年第5期40卷 844-851页

作者：李良勇马莉李亚军梅灯安徽中医药大学第一附属医院安徽合肥230031 安徽中医药大学中西医结合学院安徽合肥230001

目的:探讨人参皂苷Rc对脑缺血再灌注损伤(CIRI)小鼠的保护作用,并从细胞焦亡角度阐释其作用机制。方法:将C57BL/6小鼠随机分为假手术(sham)组、大脑中动脉闭塞/再灌注(MCAO/R)组、人参皂苷Rc+MCAO/R组(Rc组)、AMP活化蛋白激酶(AMPK)激... 详细信息

目的:探讨人参皂苷Rc对脑缺血再灌注损伤(CIRI)小鼠的保护作用,并从细胞焦亡角度阐释其作用机制。方法:将C57BL/6小鼠随机分为假手术(sham)组、大脑中动脉闭塞/再灌注(MCAO/R)组、人参皂苷Rc+MCAO/R组(Rc组)、AMP活化蛋白激酶(AMPK)激动剂阿卡地新(AICAR)+MCAO/R组(agonist组)和人参皂苷Rc+MCAO/R+AMPK抑制剂Compound C组(Rc+inhibitor组)。对agonist组小鼠给予AICAR(500 mg/kg)腹腔注射,Rc+inhibitor组小鼠给予Compound C(20 mg/kg)腹腔注射;Rc组和Rc+inhibitor组小鼠造模后给予人参皂苷Rc(40 mg/kg)灌胃,每天一次,连续7 d;sham组和MCAO/R组则给予等体积的纯化水。Zea Longa评分观察小鼠神经功能缺损程度,TTC染色观察小鼠脑梗死体积,干湿重法观察小鼠脑水肿程度,HE染色观察小鼠脑组织病理形态的改变,RT-qPCR和Western blot检测小鼠脑组织AMPK、核苷酸结合寡聚化结构域样受体蛋白3(NLRP3)、胱天蛋白酶1(caspase-1)和焦亡效应蛋白消皮素D(GSDMD)的表达,EliSA检测炎症因子白细胞介素1β(IL-1β)和IL-18的含量。结果:Rc组和agonist组小鼠神经功能缺损症状减轻,脑梗死体积减小,脑水肿和神经元病理损伤受到抑制,脑组织pAMPK/AMPK比值和AMPK mRNA表达水平升高,细胞焦亡相关蛋白NLRP3、caspase-1和GSDMD的mRNA和蛋白表达水平降低,炎症因子IL-1β和IL-18表达水平降低。Rc+inhibitor组小鼠脑组织p-AMPK/AMPK比值和AMPK mRNA表达水平较Rc组显著下降(P<0.05),NLRP3、caspase-1和GSDMD的mRNA和蛋白表达水平,以及IL-1β和IL-18表达水平显著升高(P<0.05),小鼠神经功能缺损程度评分升高,脑梗死体积增大,脑水肿和神经元病理损伤显著加重(P<0.05)。结论:人参皂苷Rc可能通过活化AMPK通路抑制NLRP3/caspase-1/GSDMD介导的细胞焦亡,从而减轻小鼠CIRI。

关键词：人参皂苷Rc 脑缺血再灌注损伤 AMP活化蛋白激酶细胞焦亡

Simultaneous Reduction of Aldehyde Group to Hydroxymethyl Group in Palladium-catalyzed Suzuki Cross-coupling Reaction

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Chemical Research in Chinese Universities 2014年第4期30卷 614-618页

作者： WANG Yingchun li Xiuying li yajun PAN Yingming CHENG Keguang WANG Hengshan College of Chemistry and Chemical Engineering Jishou University Jishou 416000 P. R. China Key Laboratory for Chemistry and Molecular Engineering of Medicinal Resources Ministry of Education School of Chemistry & Chemical Engineering Guangxi Normal University Guilin 541004 P. R. China

The authors presented an efficient method for the palladium-catalyzed Suzuki cross-coupling reaction with the simultaneous reduction of the aldehyde to a hydroxymethyl group.This method allows halide substituted aryl aldehydes to readily react with arylboronic acids,producing polycyclic aromatic alcohols in moderate to good yields.The reaction was catalyzed by Pd（OAc）2（3％,molar fraction） at 150 ℃ in the presence of 6％（molar fraction）1,4-diazabicyclo[2.2.2]octane（DABCO） and 3 times the molecular weight of K2CO3 in the mixture solvent of N,N-dimethylformamide（DMF）/H2O [V（DMF）∶ V（H2O）=5∶1].

关键词： Palladium Suzuki cross-coupling Reduction Polycyclic aromatic alcohol

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基于机器视觉的菠萝自动去眼方法与试验

农业工程学报 2024年第1期40卷 80-89页

作者：刘安稳谢方平向阳李亚军雷翔茗湖南农业大学机电工程学院长沙410128 智能农机装备湖南省重点试验室长沙410128 北京农林科学院智能装备研究中心北京100097

菠萝加工过程中的去眼作业目前主要依赖人工手动操作,劳动成本高且作业效率低。为实现自动化菠萝去眼作业,该研究运用YOLOv5目标检测算法对菠萝眼进行快速识别,将所有角度相差90o的两张图片作为一组进行立体匹配分析以获取菠萝眼的三维... 详细信息

菠萝加工过程中的去眼作业目前主要依赖人工手动操作,劳动成本高且作业效率低。为实现自动化菠萝去眼作业,该研究运用YOLOv5目标检测算法对菠萝眼进行快速识别,将所有角度相差90o的两张图片作为一组进行立体匹配分析以获取菠萝眼的三维位置信息。通过旋转菠萝和轴向移动去眼刀具将专用去眼刀具依次对准每一个菠萝眼并快速去除。试验结果表明:YOLOv5目标检测算法对菠萝眼识别效果良好,验证集的准确率、召回率和平均精度均值均高于96%;菠萝眼实际中心与探针刺入位置的平均误差为1.01 mm,最大误差为2.17 mm,均方根误差为1.09 mm;菠萝眼的完全去除率为89.5%、不完全去除率为6.2%,漏检率为4.3%,单个菠萝去眼时间为110.9 s,基本满足自动化去眼作业需要。研究结果可为菠萝自动去眼机研发提供技术参考。

关键词：农业机械机器视觉设计菠萝眼 YOLOv5 三维定位

LncRNA LUCAT1激活自噬对肺腺癌A549干细胞影响的研究

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中华肿瘤防治杂志 2024年第1期31卷 11-18页

作者：王鑫姜梅李乐瑶李雷王海伦李亚军遵义医科大学第三附属医院肿瘤科遵义市第一人民医院贵州遵义563000 遵义医科大学第三附属医院中心实验室遵义市第一人民医院贵州遵义563000

目的探讨LncRNA LUCAT1在肺腺癌A549干细胞(A549/SC)中与细胞自噬调控的关系,及其对A549/SC增殖和迁移的影响。方法通过qRT-PCR检测A549/SC和肺腺癌A549亲本细胞(A549/MN)中LncRNA LUCAT1的表达情况。慢病毒转染构建稳定敲低LncRNA LUC... 详细信息

目的探讨LncRNA LUCAT1在肺腺癌A549干细胞(A549/SC)中与细胞自噬调控的关系,及其对A549/SC增殖和迁移的影响。方法通过qRT-PCR检测A549/SC和肺腺癌A549亲本细胞(A549/MN)中LncRNA LUCAT1的表达情况。慢病毒转染构建稳定敲低LncRNA LUCAT1的A549/SC细胞株(sh-LUCAT1)及对照株(NC-sh LUCAT1);CCK8实验、克隆形成实验、Transwell迁移实验检测抑制LUCAT1表达后细胞增殖和迁移的变化。通过蛋白质印迹法检测各转染组细胞中干性和自噬相关蛋白的表达变化。2组样本比较采用独立样本t检验,采用单因素方差分析对组间差异比较结果进行检验。结果无血清悬浮培养法可富集得到A549/SC。与A549/MN相比,A549/SC中干性相关蛋白CD44、Nanog和Bmi-1表达水平均升高,均Plin 1和LC3Ⅱ/LC3Ⅰ较A549/MN表达增高,而p62蛋白表达较其亲本细胞偏低,均Plin 1(t=5.460,P=0.005)、LC3Ⅱ/LC3Ⅰ(t=4.748,P=0.009)表达下降,p62蛋白(t=2.929,P=0.043)表达升高,差异均有统计学意义。结论在A549/SC中存在高表达的LncRNA LUCAT1,LUCAT1可激活自噬从而促进A549/SC的增殖和迁移。

关键词：肺癌肺腺癌A549干细胞肺癌相关转录本1 自噬

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福山的身份政治理论争论及其批判

郑州轻工业大学学报（社会科学版） 2024年第3期25卷 41-49页

作者：李亚军天津师范大学政治与行政学院天津300387

通过分析身份政治对美国民主政治的理性话语、政治体制、社会整合和发展议题的消极影响,福山表明了对身份政治的反对态度,并提出构建以“信条式国家认同”为基础的统一身份。围绕福山的理论框架,塞兹等反对者仅从身份政治的进步性方面... 详细信息

通过分析身份政治对美国民主政治的理性话语、政治体制、社会整合和发展议题的消极影响,福山表明了对身份政治的反对态度,并提出构建以“信条式国家认同”为基础的统一身份。围绕福山的理论框架,塞兹等反对者仅从身份政治的进步性方面为其辩护,认为身份政治有助于增强政治民主和社会进步,因而其批判还存在片面性和局限性。从美国政治发展的历程来看,社会阶级斗争的范式和结构动态逐步强化,身份政治只是资本主义社会阶级政治范式下的一种暂时的方式,在很大程度上反映出西方社会民主主流价值和体制本身的内在缺陷,而要消除身份政治带来的消极影响,其关键是要正确认识和处理多元与统一之间的关系。

关键词：身份政治福山民主危机信条式国家认同民主政治