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Chinese Journal of Chemical Engineering 2020年第1期28卷 23-32页

作者： Weishu Wang Yihan Liao Youzhi Yan Bingchao Zhao Tao Wang Shanshan Shangguan North China University of Water Resources and Electric Power Zhengzhou 450045China

To develop an appropriate falling film evaporation device for organic fluid cogeneration, a numerical study on the gas–liquid two-phase counter-current flow characteristics of R113 inside a vertical tube under different structural conditions was conducted using the Fluent software. The effects of the tube length, tube diameter, and annular gap on the falling film flow characteristics were determined, respectively. The results indicated that under a certain spray density, the falling film thickness in the region of the steady section was almost constant with different structural parameters for the tube diameter, tube length, and annular gap. In addition, a smaller tube diameter resulted in a steadier film flow. When the tube diameter decreased to a specific value, the film thickness showed a uniform distribution along the wall surface. This indicated that a best falling tube diameter exists. Meanwhile, the film fluctuation was enhanced with an increase in the tube length. When the tube length was greater than 1.2 m, the falling film splashed and could not completely wet the wall surface. The film fluctuation was enhanced by decreasing the annular gap, and the film could not be formed when the annular gap was smaller than 1.2 mm.

关键词： Falling film Numerical simulation R113

Machine Learning Based Quantitative Damage Monitoring of Composite Structure

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International Journal of Smart and Nano Materials 2022年第2期13卷 167-202页

作者： Xinlin Qing Yunlai liao yihan Wang Binqiang Chen Fanghong Zhang Yishou Wang School of Aerospace Engineerin Xiamen UniversityXiamenFujian China National Center for Applied Mathematics Chongqing Normal UniversityChongqingSichuan China

Composite materials have been widely used in many industries due to their excellent mechanical properties.It is difficult to analyze the integrity and durability of composite structures because of their own characteristics and the complexity of load and environments.Structural health monitoring(SHM)based on built-in sensor net-works has been widely evaluated as a method to improve the safety and reliability of composite structures and reduce the operational cost.With the rapid development of machine learning,a large number of machine learning algorithms have been applied in many disciplines,and also are being applied in the field of SHM to avoid the limitations resulting from the need of physical models.In this paper,the damage monitoring technologies often used for composite structures are briefly outlined,and the applications of machine learning in damage monitoring of composite structures are concisely reviewed.Then,challenges and solutions for quanti-tative damage monitoring of composite structures based on machine learning are discussed,focusing on the complete acquisi-tion of monitoring data,deep analysis of the correlation between sensor signal eigenvalues and composite structure states,and quantitative intelligent identification of composite delamination damage.Finally,the development trend of machine learningbased SHM for composite structures is discussed.

关键词： Composite structure structural health monitoring machine learning built-in sensor network structural damage

Intergrowth mechanism and morphology prediction of faceted Al_(3)Ni formed during solidification by a spatial geometric model

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Journal of Materials Science & Technology 2020年第19期54卷 40-47页

作者： Zongye Ding Qiaodan Hu Wenquan Lu Fan Yang yihan Zhou Naifang Zhang Sheng Cao liao Yu Jianguo Li Shanghai Key Laboratory of Materials Laser Processing and Modification School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China State Key Laboratory of Advanced Special Steel Shanghai UniversityShanghai200444China School of Mechanical Engineering Shanghai Jiao Tong UniversityShanghai 200240China School of Materials University of ManchesterOxford RoadManchester M139PLUK

The interplay and intergrowth characteristic of faceted intermetallic compounds(IMCs)during solidification was originally investigated through the rod-like Al3 Ni crystals in the liquid Al/solid Ni interconnection by using synchrotron radiography,and the diversified 3-D morphologies were reconstructed by synchrotron tomography.A spatial geometric model was established to effectively predict the diversified growth patterns of two spatial crystals.For the two overlapping Al3 Ni crystals,the impeded crystal growth was divided into three different stages,decided by the hindrance form the other crystal.Further,the groove formed on the crystal surface is directly related to the solute redistribution under the critical condition of boundary layer thickness larger than two crystals distance.The closer distance and smaller crystal size indicate the deeper and larger groove,and the morphology changes from hemispheroid to hemi-ellipsoid with the increased opposite and interacted faces.

关键词： Solidification Synchrotron radiography Intergrowth behaviour Intermetallic compounds 3-D morphology

Numerical Simulation and Optimization of Staged Combustion and NO_x Release Characteristics in Precalciner

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Journal of Thermal Science 2019年第5期28卷 1024-1034页

作者： WANG Weishu liao yihan LIU Jun HUANG Zhihao TIAN Miao Thermal Engineering Research Centre North China University of Water Resources and Electric Power

In order to study the combustion characteristics in a precalciner, the temperature and composition field in a typical Trinal-sprayed calciner were numerically analysed. The results obtained by simulation were compared to actual measurements and the simulated results were in good agreement with the measured ones. The results indicated that the aerodynamic flow field in the precalciner is satisfactory, and a symmetrical reflux occurs in the shrinkage zone of the precalciner because of air staging, which can increase the residence time of the solid particles. The temperature distribution in the furnace is uniform, and the average temperature is greater than 1200 K, which can satisfy the conditions for the pulverised coal combustion and raw material decomposition. The mass fraction distribution of oxygen, carbon monoxide, and carbon dioxide in the precalciner is closely related to the temperature distribution. The concentration of nitrogen oxides(NO_x) exhibits a trend of increasing, decreasing and then increasing, and finally tending to a stable level. Within a certain velocity range, the average temperature in the precalciner and the decomposition efficiency of the raw material increase as the flue gas velocity increases. When the flue gas velocity is 24 m/s, the overall performance of the precalciner is optimal.

关键词： TTF precalciner staged combustion NOx emission characteristics optimization

Random Terpolymer Based on Simple Siloxane-functionalized Thiophene Unit Enabling High-performance Non-fullerene Organic Solar Cells

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Chinese Journal of Polymer Science 2024年第3期42卷 311-321,I0006页

作者： Fuliang Cheng Shiting Lai yihan Zhang Ling Xue Xinxin Xia Peipei Zhu Xinhui Lu Xunfan liao Yiwang Chen National Engineering Research Center for Carbohydrate Synthesis/Key Laboratory of Fluorine and Silicon for Energy Materials and Chemistry of Ministry of Education College of Chemistry and Chemical EngineeringJiangxi Normal UniversityNanchang 330022China Department of Physics Chinese University of Hong Kong New TerritoriesHong Kong 999077China Institute of Polymers and Energy Chemistry(IPEC)/Jiangxi Provincial Key Laboratory of New Energy Chemistry Nanchang UniversityNanchang 330031China

Incorporation of siloxane-functionalized units into polymers backbone has proven to be an efficient strategy to improve photovoltaic performance. In this work, a low-cost siloxane-containing unit was developed to construct a series of terpolymers, and the effects of siloxane on the polymer performance were systematically studied. Different contents of thiophene containing siloxane-functionalized side chain were introduced into PM6 to obtain a series of polymers(PM6, PM6-SiO-10, PM6-SiO-20 and PM6-SiO-30). The siloxane-functionalized side chains in polymers have only a slight effect on the absorption behavior and frontier molecular orbitals. However, when the siloxane content increased, the terpolymers' aggregation property decreased and the temperature-dependency increased, leading to improved donor-acceptor compatibility. The power conversion efficiency(PCE) based on PM6:Y6, PM6-SiO-20:Y6 and PM6-SiO-30:Y6 devices was 15.64%, 16.03% and 15.82%, respectively. In comparison, the active layer based on PM6-SiO-10:Y6 exhibits the most appropriate phase separation morphology, resulting in effective exciton dissociation, more balanced hole-electron transport and less recombination. Consequently, the highest PCE of 16.69% with an outstanding shortcircuit current density of 26.96 mA·cm^(-2) was obtained, which are one of the highest values for siloxane-functionalized polymer-based devices.This work demonstrates that finely controlling the content of siloxane-functionalized thiophene is beneficial for obtaining high-performance terpolymer donors and provides a novel and low-cost method to improve photovoltaic performance.

关键词： Organic solar cells Terpolymers Siloxane-functionalized unit Low-cost Morphology

Physical regulation of copper catalyst with a hydrophobic promoter for enhancing CO_(2)hydrogenation to methanol

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The Innovation 2023年第4期4卷 67-73页

作者： Hangjie Li Wei Fang Ling-Xiang Wang Yifeng Liu Lujie Liu Tulai Sun Ciqi liao yihan Zhu Liang Wang Feng-Shou Xiao Key Lab of Biomass Chemical Engineering of Ministry of Education College of Chemical and Biological EngineeringZhejiang UniversityHangzhou 310028China Key Laboratory of Applied Chemistry of Zhejiang Province Department of ChemistryZhejiang UniversityHangzhou 310028China Center for Electron Microscopy State Key Laboratory Breeding Base of Green Chemistry Synthesis TechnologyCollege of Chemical EngineeringZhejiang University of TechnologyHangzhou 310014China

The hydrogenation of CO_(2)to methanol,which is restricted by water products,requires a selective removal of water from the reaction system.Here,we show that physically combining hydrophobic polydivinylbenzene with a copper catalyst supported by silica can increase methanol production and CO_(2)conversion.Mechanistic investigation reveals that the hydrophobic promoter could hinder the oxidation of copper surface by water,maintaining a small fraction of metallic copper species on the copper surface with abundant Cu^(δ+),resulting in high activity for the hydrogenation.Such a physically mixed catalyst survives the continuous test for 100 h owing to the thermal stability of the polydivinylbenzene promoter.

关键词： copper methanol hydrogenation

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基于分数膨胀现象的教学评价改进方法

高教发展与评估 2023年第6期39卷 32-41,I0003,I0004页

作者：张傲廖睿智陈奕含李树祯香港中文大学(深圳) 广东深圳518172 南开大学滨海学院天津300270

随着高校学生评教制度的广泛应用,部分教师为了让教学评价结果符合学校考核要求和自身预期,在教学过程中迎合学生对于高分的偏好,导致了分数膨胀现象;部分高校追求更好的升学、就业数据,利用信息时间差从分数膨胀现象中短暂得利。高校... 详细信息

随着高校学生评教制度的广泛应用,部分教师为了让教学评价结果符合学校考核要求和自身预期,在教学过程中迎合学生对于高分的偏好,导致了分数膨胀现象;部分高校追求更好的升学、就业数据,利用信息时间差从分数膨胀现象中短暂得利。高校、教师和学生三方为了各自的短期利益,陷入了对各方都有负面影响的恶性博弈,形成代理人问题。对比研究哈佛大学和加州大学伯克利分校的教学评价体系,分析两所高校在分数膨胀趋势下仍保持评价有效性的原因和措施,并基于过去70年间美国200余所公立和私立高校本科学生以及部分国内高校学生的成绩数据,结果发现:相比控制高分率而言,采取控制均分的方法更加有利于控制分数膨胀现象。故而约束教师利用分数膨胀“兑换”更优的教学评价是本研究的意义所在。

关键词：分数膨胀教学评价课程考核考试分数

下调缺氧诱导性脂肪酸结合蛋白5(FABP5)表达抑制Huh7细胞的促血管生成能力

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细胞与分子免疫学杂志 2021年第12期37卷 1092-1097页

作者：庞亿寒肖衡廖锐潘龙重庆医科大学附属第一医院泌尿外科实验室重庆400016 重庆医科大学附属第一医院肝胆外科重庆400016

目的探讨脂肪酸结合蛋白5(FABP5)在肝癌缺氧诱导的血管生成中的作用及机制。方法Huh7细胞进行常规培养及低氧培养;FABP5小干涉RNA(FABP5 siRNA)转染敲低Huh7细胞FABP5表达,反转录PCR检测FABP5 mRNA表达,Western blot法检测FABP5、血管... 详细信息

目的探讨脂肪酸结合蛋白5(FABP5)在肝癌缺氧诱导的血管生成中的作用及机制。方法Huh7细胞进行常规培养及低氧培养;FABP5小干涉RNA(FABP5 siRNA)转染敲低Huh7细胞FABP5表达,反转录PCR检测FABP5 mRNA表达,Western blot法检测FABP5、血管内皮生长因子A(VEGFA)表达,ELISA检测Huh7细胞上清液VEGFA浓度;成管实验检测Huh7细胞上清液诱导人脐静脉内皮细胞(HUVEC)的成管能力。结果低氧培养后,FABP5 mRNA以及FABP5及VEGFA蛋白表达增加;采用FABP5 siRNA转染后,低氧培养Huh7细胞VEGFA表达及分泌均下降,低氧培养Huh7细胞上清液诱导HUVEC的成管能力下降。结论缺氧诱导Huh7细胞FABP5表达增加,敲低FABP5则抑制Huh7细胞VEGFA表达及HUVEC的成管能力。

关键词：脂肪酸结合蛋白5(FABP5) Huh7细胞血管生成细胞缺氧

DNA alkylation lesion repair: outcomes and implications in cancer chemotherapy

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2021年第1期22卷 47-62页

作者： yihan PENG Huadong PEI Department of Biochemistry and Molecular Medicine the George Washington University School of Medicine and Health SciencesWashingtonDC 20037USA GW Cancer Center the George Washington University School of Medicine and Health SciencesWashingtonDC 20052USA

Alkylated DNA lesions, induced by both exogenous chemical agents and endogenous metabolites, represent a major form of DNA damage in cells. The repair of alkylation damage is critical in all cells because such damage is cytotoxic and potentially mutagenic. Alkylation chemotherapy is a major therapeutic modality for many tumors, underscoring the importance of the repair pathways in cancer cells. Several different pathways exist for alkylation repair, including base excision and nucleotide excision repair, direct reversal by methyl-guanine methyltransferase(MGMT), and dealkylation by the AlkB homolog(ALKBH) protein family. However, maintaining a proper balance between these pathways is crucial for the favorable response of an organism to alkylating agents. Here, we summarize the progress in the field of DNA alkylation lesion repair and describe the implications for cancer chemotherapy.

关键词： Alkylation repair Base excision repair Methyl-guanine methyltransferase(MGMT) AlkB homolog(ALKBH)

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包装内初始氧对米威化饼干货架期的影响

食品与发酵工业 2020年第8期46卷 136-141页

作者：钱奕含卢立新潘嘹卢莉璟江南大学机械工程学院江苏无锡214122 江苏省食品先进制造装备技术重点实验室江苏无锡214122

为了探讨包装内氧气浓度对一种易氧化的新型食品--米威化饼干的货架期影响,该研究设计了4种不同包装内氧气浓度条件,并在50℃下对此产品进行了加速试验,测试了产品的过氧化值(peroxide value,POV)、色差及感官变化。除此之外,通过测试... 详细信息

为了探讨包装内氧气浓度对一种易氧化的新型食品--米威化饼干的货架期影响,该研究设计了4种不同包装内氧气浓度条件,并在50℃下对此产品进行了加速试验,测试了产品的过氧化值(peroxide value,POV)、色差及感官变化。除此之外,通过测试不同储存温度条件下米威化的POV变化,建立了常氧下米威化货架期预测模型。试验结果表明,产品的POV随着时间延长而升高,且包装内氧气浓度越低,POV变化速率越低。50℃下,常氧包装的产品在第37天超过国标规定POV(0.25 g/100g),而真空包装的产品42 d的POV仅为0.088 g/100g,根据国标规定值预测货架期为83 d,氧气浓度对产品货架期影响显著。色差整体呈波动上升,感官品质随时间延长而下降。该产品常温常氧下预测货架期为107 d。该研究建立了在大气组分条件下米威化饼干的货架期预测模型,预测误差在±10%之内,为此产品的抗氧化包装设计提供了理论依据。

关键词：米制品威化饼干货架期氧化初始氧