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2022 1

2018 1

2016 1

2014 1

2011 2

2009 2

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统计偏析度 2

统计符合度 2

仿生与生物启发膜 1

仿生矿化 1

仿生黏合 1

原位统计分布分析 1

原位统计分布分析表征技术 1

夹杂 1

模具钢 1

膜和膜过程 1

表面偏析 1

质量控制 1

铌 1

高温合金压气机盘 1

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Modeling of solids segregation in circulating fluidized bed boilers

Xuan YAO, Tao WANG, Jia ZHAO, Hairui YANG, Hai ZHANG

《能源前沿（英文）》 2011年第5卷第1期页码 115-119 doi: 10.1007/s11708-010-0103-0

摘要： Segregation always occurs in a circulating fluidized bed (CFB) because of the wide distribution of particle size and density of the bed material. Terminal velocity has a significant influence on solids segregation; thus, it is convenient to describe the segregation tendency using single particle terminal velocity . This paper proposes a segregation model in CFB boilers based on the Cell Model. In each cell along the riser, varied-sized particles have different tendencies toward segregation; finer particles are carried out more easily, while coarser ones tend to sink into the cell. It is assumed that the average terminal velocity , corresponding to the mean particle size in the cell, has a segregation index of = 1.0 as the reference point. The segregation index of particles with higher terminal velocity is lower than 1.0, while that for finer particles is larger than 1.0. The empirical formulae of segregation parameters, namely and , are derived by optimizing experimental data in published literature. The test result of ash size distribution in a 220 t/h CFB boiler validates the reasonableness of the model.

关键词： segregation model terminal velocity circulating fluidized bed (CFB)

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Temperature segregation and its impact on the quality and performance of asphalt pavements

Minkyum KIM, Pranjal PHALTANE, Louay N. MOHAMMAD, Mostafa ELSEIFI

《结构与土木工程前沿（英文）》 2018年第12卷第4期页码 536-547 doi: 10.1007/s11709-017-0451-5

摘要： Temperature segregation is non-uniform temperature distributionacross the uncompacted asphalt mat during paving operations and mayhave detrimental effects on the quality and performance of asphaltpavements. However, many research studies conducted across the UShave reported mixed observations regarding its effects on the initialquality and long-term performance of asphalt pavements.?The objectiveof this study was to determine the effects of the temperature segregationon the density and mechanical properties of Louisiana asphalt mixtures.Seven asphalt rehabilitation projects across Louisiana were selected.A multi-sensor infrared bar (Pave-IR) system and a hand-held portablethermal camera were used to measure the temperature of asphalt mats.Field core samples were collected from various areas with varyingseverity levels of temperature segregation and tested for the density,fracture resistance (J ) by semi-circular bending(SCB), rut depth by wheel tracking, and dynamic modulus (|E*|) byindirect tension (IDT) devices.?Two distinctive patterns of non-uniformtemperature distribution were observed: a cyclic and irregular temperaturesegregations. Laboratory test results showed that highly temperaturesegregated asphalt pavements (i.e., temperature differentials ≥41.7°C) can have significantly lower densities and the mechanicalproperties than the non-segregated area, especially when the temperaturedifferentials are measured at compaction.

关键词： temperature segregation temperature differential pavement density semi-circular bending wheel tracking dynamic modulus

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Improved blending strategy for membrane modification by virtue of surface segregation using surface-tailored

Shuai Liang, Peng Gao, Xiaoqi Gao, Kang Xiao, Xia Huang

《环境科学与工程前沿（英文）》 2016年第10卷第6期 doi: 10.1007/s11783-016-0875-5

摘要： Two types of amphiphilic nanoparticles were prepared via silanization reaction. Amphiphilic nanoparticles tend to protrude from membrane matrix by segregation. Blending with amphiphilic nanoparticles further enhances membrane hydrophilicity. Excessive silanization cause adverse effect on blending efficiency. Membrane modification is one of the most feasible and effective solutions to membrane fouling problem which tenaciously hampered the further augmentation of membrane separation technology. Blending modification with nanoparticles (NPs), owing to the convenience of being incorporated in established membrane production lines, possesses an advantageous viability in practical applications. However, the existing blending strategy suffers from a low utilization efficiency due to NP encasement by membrane matrix. The current study proposed an improved blending modification approach with amphiphilic NPs (aNPs), which were prepared through silanization using 3-(Trimethoxysilyl)propyl methacrylate (TMSPMA) as coupling agents and ZnO or SiO as pristine NPs (pNPs), respectively. The Fourier transform infrared and X-ray photoelectron spectroscopy analyses revealed the presence of appropriate organic components in both the ZnO and SiO aNPs, which verified the success of the silanization process. As compared with the pristine and conventional pNP-blended membranes, both the ZnO aNP-blended and SiO aNP-blended membranes with proper silanization (100% and 200% w/w) achieved a significantly increased blending efficiency with more NPs scattering on the internal and external membrane surfaces under scanning electron microscope observation. This improvement contributed to the increase of membrane hydrophilicity. Nevertheless, an extra dosage of the TMSPMA led to an encasement of NPs, thereby adversely affecting the properties of the resultant membranes. On the basis of all the tests, 100% (w/w) was selected as the optimum TMSPMA dosage for blending modification for both the ZnO and SiO types.

关键词： Membrane modification Nanoparticle Hydrophilic Amphiphilic Blending

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Micromixing performance of the teethed high shear mixer under semi-batch operation

《化学科学与工程前沿（英文）》 2022年第16卷第4期页码 546-559 doi: 10.1007/s11705-021-2069-3

摘要： Semi-batch operated reaction processes are necessary for some competitive reaction systems to achieve a desirable process selectivity and productivity of fine chemical products. Herein the structural and operating parameters of the teethed high shear mixers were adjusted to study the micromixing performance in the semi-batch operated system, using the Villermaux/Dushman reaction system. The results indicate that the rising of the rotor speed and the number of rotor teeth, the decrease of the width of the shear gap and the radial distance between the feed position and the inner wall of stator can enhance the micromixing level and lead to the decrease of the segregation index. Additionally, computational fluid dynamics calculations were carried out to disclose the evolution of the flow pattern and turbulent energy dissipation rate of the semi-batch operated high shear mixer. Furthermore, the correlation was established with a mean relative error of 8.05% and R² of 0.955 to fit the segregation index and the parameters studied in this work, which can provide valuable guidance on the design and optimization of the semi-batch operated high shear mixers in practical applications.

关键词： high shear mixer semi-batch operation micromixing performance Villermaux/Dushman system segregation index

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Effects of irradiation on chromium’s behavior in ferritic/martensitic FeCr alloy

Xinfu HE, Wen YANG, Zhehao QU, Sheng FAN

《能源前沿（英文）》 2009年第3卷第2期页码 181-183 doi: 10.1007/s11708-009-0025-x

摘要： The effects of irradiation on chromium performance under different temperatures in Fe-20at%Cr were modeled by modified Marlowe code. Chromium precipitation was observed in FeCr alloy after irradiation; interstitial Chromium atoms are the preferred formation of mixed Fe-Cr dumbbells in the direction of<110>and<111>; interstitial chromium atoms congregated on {111} and {110} plane. The results are compared with experiment observations and are useful to understanding the irradiation performances of FeCr alloy.

关键词： irradiation Fe-20at%Cr alloy chromium segregation

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热作模具钢的原位统计分布分析

王海舟,李美玲,张秀鑫,吴超

《中国工程科学》 2009年第11卷第10期页码 39-47

摘要：

采用原位统计分布分析技术对不同来源的模具钢进行解析，获得了模具钢坯横剖面较大尺度范围内各化学组成的位置分布、状态分布、含量分布的一系列新信息；定量表征了不同来源模具钢的最大偏析度、统计偏析度、统计符合度、统计致密度、统计疏松度、夹杂物种类和含量以及粒度统计分布等参数的差异性，可用于不同来源模具钢质量差异解析的参考。

关键词：原位统计分布分析模具钢统计偏析度统计符合度夹杂

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高温合金压气机盘锻件纵断面中铌分布的原位统计分布分析表征

王海舟,李美玲,庄景云

《中国工程科学》 2011年第13卷第10期页码 19-27

摘要：

采用原位统计分布分析表征技术系统研究了GH169高温合金压气机盘纵断面不同部位铌分布的规律。以所得到的与样品原位置相对应的数以万计原始信号系统解析为基础，进而获得压气机盘锻件的纵断面不同部位铌的定量统计分布信息以及加工工艺过程中铌的迁移规律。准确计算判定了盘纵断面不同部位铌的最大偏析度，提出了95 %置信度时中位值置信扩展率,即统计偏析度（S）新参数，用以表征铌在压气机盘中分布的均匀度；提出了所有数据在特定含量区间（C₀±R）的频度（权重）比率，即统计符合度（F）新参数，用以表征预设质量控制区间铌含量的一致性的概率。采用原位统计分布分析的表征方法，准确定量地评定了高温合金压气机盘件纵断面不同部位铌的分布均匀度和符合度，为加工后盘件的质量控制评估提供了参考。

关键词：原位统计分布分析表征技术高温合金压气机盘铌统计偏析度统计符合度质量控制

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仿生与生物启发膜的研究进展

彭冬冬,贺明睿,杨昊,张蓓,高博鑫,范琳,丁鹤,南延虎,潘福生,苏延磊,吴洪,姜忠义

《中国工程科学》 2014年第16卷第12期页码 102-112

摘要：

仿生与生物启发的思想和策略在众多基础与工程科学领域取得了重要进展。研究者们通过借鉴和模仿自然界中生物材料多样的组成、精巧的结构、温和的形成过程以及强大的功能，设计制备了多种高性能膜材料，并将其应用于水处理、气体分离、有机小分子液体混合物分离等领域，显示出良好的应用前景。仿生和生物启发膜主要是以细胞膜、荷叶和贻贝等为仿生原型，以生物矿化、生物黏合和自组装等为工具，以绿色、高效、节能为目标，在资源、能源高效利用和可持续发展等方面会发挥越来越大的作用，并逐步发展成为膜和膜过程领域的重要分支。本文将对仿生和生物启发膜的研究进展进行简要总结，重点介绍抗污染膜、杂化膜和复合膜的制备与应用。

关键词：仿生与生物启发膜膜和膜过程表面偏析仿生矿化仿生黏合