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高分子学报 2007年第10期17卷 901-904页

作者：袁望章赵辉徐海鹏孙景志 lam j w.y.毛宇金佳科张双郑强唐本忠浙江大学高分子科学与工程学系教育部高分子合成与功能构造重点实验室杭州310027 香港科技大学化学系

采用不同的双取代聚乙炔与多壁碳纳米管复合,通过π-π相互作用和聚合物链缠绕实现了对碳纳米管的增溶.这种方法对碳纳米管的结构没有损害,而且包覆到碳纳米管表面的双取代聚乙炔也显示了自身的荧光发射特性.

关键词：双取代聚乙炔缠绕碳纳米管增溶

Monotropic smectic A to double layer smectic C transition of biphenyl containing liquid crystal acetylene

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Chinese Chemical Letters 2011年第11期22卷 1355-1358页

作者： Zhen Qiang yu CaiZhenZhu Zhe Zhang jian Hong Liu jacky w.y. lam Ben Zhong Tang Shenzhen Key Laboratory of Functional Polymers and School of Chemistry and Chemical Engineering Shenzhen University Shenzhen 518060 China Department of Chemistry The Hong Kong University of Science and Technology Clear Water BayKowloonChina

5-[（4＇-Heptoxy-4-biphenylyl）carbonyloxy]-1-pentyne（A-3,7） was synthesized and the phase structures and transitions were investigated by differential scanning calorimetry（DSC）,wide angle X-ray diffraction（wAXD）,polarized light microscopy（PLM） and the molecular packing in the crystal and liquid crystalline phases were simulated by molecular dynamic *** results showed that the sample formed thermodynamically metastable SmA and SmC_2 phases before crystallized during cooling and the crystal phase directly transformed into isotropic phase during heating.

关键词： Liquid crystal Phase structure Phase transition Smectic phase X-ray diffraction

n型Bi2Te2.7Se0.3热电材料选区激光熔化成形工艺与性能的研究

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n型Bi2Te2.7Se0.3热电材料选区激光熔化成形工艺与性能的研究

作者：毛宇武汉理工大学

学位级别：硕士

BiTe基热电材料是室温下热电性能(ZT.0)最好的材料之一,在低温发电以及制冷领域有着广泛应用。目前商业上主要是通过区熔法来制备BiTe热电材料块体,然后还要经过一系列的切割、焊接和组装等工序,才能最终获得所需热电器件,该工艺过程周... 详细信息

BiTe基热电材料是室温下热电性能(ZT.0)最好的材料之一,在低温发电以及制冷领域有着广泛应用。目前商业上主要是通过区熔法来制备BiTe热电材料块体,然后还要经过一系列的切割、焊接和组装等工序,才能最终获得所需热电器件,该工艺过程周期长、能耗高、材料损耗大,这些因素都限制了热电技术的进一步大规模应用。选区激光熔化成形技术(Selective Laser Melting,SLM)是一种增材制造(Additive Manufacturing,AM)技术,该技术利用离散/堆积的原理,使用高能激光束对特定区域的金属粉末进行选择性的逐行、逐层熔化,从而实现金属零件的成形制造。该技术在热电材料及器件的成形制造领域有着广泛应用前景,但是相关的研究报道极少。本文以传统的n型BiTeSe热电材料为研究对象,系统研究了选区激光熔化的成形工艺、化学成分、微结构及热电性能,其主要研究工作的结果如下:系统研究了SLM工艺过程中不同粉体尺寸、激光功率、扫描速率、扫描间距以及铺粉厚度等工艺参数对n型BiTeSe材料的成形质量的影响规律,并得到最优的成形工艺窗口。采用卧式和行星式两种球磨方式制备的粉体颗粒尺寸均在30μm之下,球磨转速过高和时间过长均容易引起粉体团聚。激光功率和扫描速率匹配不合适会导致出现球化、汽化以及扭曲变形等缺陷。扫描间距不宜过大,否则会降低熔道搭接率,不利于大颗粒粉体的熔融。最优成形工艺所对应的激光体能量密度E范围为10-33.3 j/mm。系统研究了n型BiTeSe热电材料在选区激光熔化过程中的成分、物相以及微结构的变化规律。SLM成形时,在熔道搭接处,材料受到激光重熔,有利于熔池内气孔的排出,但同时此区域内的元素挥发会比其他区域更严重,最终导致熔池内元素的分布不均匀,并随着成形层数增加,元素的缺失不断上升。Te和Se的挥发随着能量密度增加而显著提升。在激光能量密度下低于33.3 j/mm,Te和Se虽然也有少量挥发,但总体上化学成分的变化相对较稳定。当激光能量密度超过33.3 j/mm时,Te和Se的挥发急剧上升,并最终导致物相逐渐由BiTe向BiTe和BiTe转变。SLM试样为典型层状结构,生长方向基本平行于建造方向,能量密度较低时,晶粒尺寸排列紧密规则;能量密度较大时,晶粒排列杂乱无序,尺寸较小并有纳米颗粒出现。采用优化的成形工艺参数制备了表面平整、熔道搭接良好,边界无翘曲变形等缺陷的n型BiTeSe块体样品,但是裂纹的出现以及元素的缺失最终导致材料机械性能和热电性能均较差。采用基板预热能有效降低粉层与基体之间的温度梯度,从减少残余应力,抑制裂纹的产生,同时延长结晶时间,晶粒充分长大,排列紧密规则,而且气孔得以迁移到表面而排出;通过改变初始原料中Te和Se的配比,制备的BiTeSe(x=0.3-0.7,y=0.16-0.24)粉体,经过SLM处理后样品均为为良好单相,化学组成也得到优化,经过退火工艺处理后,样品的均匀性以及热电性能得到明显改善。在673 K温度下退火24 h后,样品的Seebeck系数面分布均匀,平均值能达到-160μV/K左右。最终,通过优化工艺参数和起始原料组成制备的块体样品经过退火后结果为良好的单相,最高ZT值在400K时可以达到0.84,与传统方法制备的材料性能相当。

关键词：热电材料 Bi2Te3 选区激光熔化化学组成显微结构热电性能

Enhanced depth resolution in optical scanning holography using a configurable pupil

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Photonics Research 2014年第2期2卷 64-70页

作者： Haiyan Ou Ting-Chung Poon Kenneth K.y.wong Edmund y.lam Department of Electrical and Electronic Engineering University of Hong KongPokfulamHong KongChina Institute of Applied Physics University of Electronic Science and Technology of China610054ChengduChina Bradley Department of Electrical and Computer Engineering Virginia TechBlacksburgVirginia 24061USA

The optical scanning holography(OSH)technique can capture all the three-dimensional volume information of an object in a hologram via a single raster *** digital hologram can then be processed to reconstruct individual sectional images of the *** this paper,we present a scheme to reconstruct sectional images in OSH with enhanced depth resolution,where a spatial light modulator(SLM)is adopted as a configurable point *** switching the SLM between two states,different Fresnel zone plates(FZPs)are generated based on the same optical *** extra information provided by different FZPs,a depth resolution at 0.7μm can be achieved.

关键词： resolution sectional Fresnel

自支撑硅氧碳纳米镶嵌复合薄膜基板的制备及导热性能研究

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功能材料 2014年第23期45卷 23122-23125页

作者：姚荣迁符长平张帅丰毛宇冯祖德厦门大学材料学院福建厦门361005 厦门大学福建省特种先进材料重点实验室福建厦门361005 厦门大学深圳研究院广东深圳518057

利用先驱体熔融纺膜法,经熔融纺膜、氧化交联及900-1200 ℃不同裂解温度制得系列自支撑硅氧碳纳米镶嵌复合薄膜.利用红外光谱（FT-IR）分析氧化交联后及高温裂解薄膜的结构变化,通过X 射线衍射（XRD）、拉曼光谱（Raman）与扫描电镜（SE... 详细信息

利用先驱体熔融纺膜法,经熔融纺膜、氧化交联及900-1200 ℃不同裂解温度制得系列自支撑硅氧碳纳米镶嵌复合薄膜.利用红外光谱（FT-IR）分析氧化交联后及高温裂解薄膜的结构变化,通过X 射线衍射（XRD）、拉曼光谱（Raman）与扫描电镜（SEM）对薄膜微观结构及形貌进行分析,采用电阻测试仪和激光热导仪对其进行电阻率与热导率进行表征.结果表明,硅氧碳纳米镶嵌复合薄膜具有较好的绝缘性能与热传导能力,随着裂解温度升高,薄膜电阻率减小,热导率大幅度增大.1200 ℃制备的样品具有合适电阻率和最佳热导率（46.8 w/（m·K））,薄膜以非晶态相SiOxCy 和游离碳为基体,细小等轴β-SiC晶弥散分布在基体中,其表面平整度高通过丝网印刷可获得两条平行的均匀致密高温银浆电路层,有望大规模应用于大功率LED封装散热基板.

关键词：自支撑硅氧碳薄膜先驱体法热导率基板

Presence of extensive intraductal component in patients undergoing breast conservative surgery predicts presence of residual disease in subsequent completion mastectomy

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Chinese Medical journal 2009年第8期122卷 900-905页

作者： Christopher C. E yiu wings T. y. Loo C. K. lam Louis w. C. Chow UNIMED Medical Institute Comprehensive Centre for Breast Diseases Hong Kong China Clinical Trial Centre Li Ka Shing Faculty of Medicine University of Hong Kong China

Background Local recurrence remains a serious problem among patients undergoing breast conservative surgery. This study aimed at identifying risk factors for residual disease after breast conservative surgery. Methods This retrospective study was based on patients with invasive breast cancer who have received breast conservative surgery and subsequent completion mastectomy. All patients had a clear resection margin in the initial operation. we analyzed the association between the presence of residual disease during completion mastectomy and the following risk factors： T staging, young age, and presence of extensive intraductal component （EIC）, a close margin, lymphovascular permeation （LVP）, positivity of estrogen receptor, progesterone receptor, and c-erbB-2. Results Residual disease was encountered in 21 （45.7%） of 46 patients; EIC was present in 28 patients （60.9%）, of whom 17 had residual disease. Presence of EIC during breast conservation surgery was associated with a higher risk of residual disease during completion mastectomy （P=0.011）. Other variables were not statistically significant risk factors for presence of residual disease. No local recurrence was recorded in our cohort, and the disease-free survival and overall survival after completion mastectomy were similar for patients who had residual disease and those who had not. Conclusions The presence of EIC is a significant risk factor for residual disease in patients after breast conservative surgery. Our findings may suggest the indicated value of completion mastectomy in patients with EIC during initial breast conservative surgery to decrease the risk of subsequent local failure.

关键词： extensive intraductal component breast conservative surgery residual disease completion mastectomy

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2017版wHO甲状腺肿瘤分类解读

中华病理学杂志 2018年第4期47卷 302-306页

作者：刘志艳周庚寅 Kennichi Kakudo Alfred K-y lam 山东大学基础医学院病理学系山东大学齐鲁医院病理科济南250012 日本近畿大学医学院奈良病院病理科 Department of Pathology School of Medicine Griffith University Gold Coast QLD 4222 Australia

2017版wHO内分泌肿瘤分类根据肿瘤的病理、临床及基因学特点，对内分泌肿瘤的分类进行了全面的更新。新版wHO中甲状腺肿瘤分类总体可分为上皮性肿瘤、非上皮性肿瘤和继发肿瘤三大类（表1），其中最重要的进展在于甲状腺滤泡上皮细胞起... 详细信息

2017版wHO内分泌肿瘤分类根据肿瘤的病理、临床及基因学特点，对内分泌肿瘤的分类进行了全面的更新。新版wHO中甲状腺肿瘤分类总体可分为上皮性肿瘤、非上皮性肿瘤和继发肿瘤三大类（表1），其中最重要的进展在于甲状腺滤泡上皮细胞起源的高分化肿瘤。乳头和滤泡、良性和恶性分类的更新，并新增加了一组甲状腺交界性肿瘤。嗜酸细胞肿瘤从滤泡性肿瘤中剔除，成为一组独立的病变。低分化癌诊断标准进一步明确。

关键词：甲状腺滤泡肿瘤分类 wHO 非上皮性肿瘤内分泌肿瘤解读嗜酸细胞肿瘤交界性肿瘤

SyNTHESIS OF A HyPERBRANCHED POLy(AROyLARyLENE) CONTAINING TRIAZOLE AND FLUORENE FUNCTIONALITIES By CLICK CHEMISTRy AND METAL-FREE,REGIOSELECTIVE POLyCyCLOTRIMERIZATION

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Chinese journal of Polymer Science 2009年第2期27卷 145-148页

作者： Cathy K.w.jim jacky w.y.lam 唐本忠 Department of Chemistry The Hong Kong University of Science & TechnologyClear Water BayKowloonHong KongChina Department of Polymer Science and Engineering Key Laboratory of Macromolecular Synthesis and Functionalization of Ministry of EducationZhejiang University

A new bis(aroylacetylene) containing tfiazole and fluorene moieties is synthesized by click chemistry. Polycyclotrimerization of the monomer is catalyzed by piperidine in refluxed dioxane,furnishing a regioregular poly(aroylarylene) in a satisfactory *** hyperbranched structure of the polymer is characterized spectroscopically with satisfactory *** polymer enjoys no metal detriment and is soluble in common organic solvents such as tetrahydrofuran (THF),chloroform,dichloromethane (DCM),and N,N-...

关键词： Regioregular Click chemistry Polycyclotrimerization Hyperbranched polymer.

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利用CI值进行衡阳晚稻产量预报方法研究

安徽农业科学 2011年第29期39卷 18185-18187页

作者：肖媚毛宇陈涛黄卓禹兰州大学大气科学院甘肃兰州730000 湖南省娄底市气象局湖南娄底417000 湖南省宁乡县气象局湖南宁乡410600 湖南省衡阳市气象局湖南衡阳421001

通过分析衡阳各县晚稻产量与综合气象干旱指数CI值的关系,利用SPSS软件剔除与预报量关系较弱的自变量,建立了CI值对晚稻产量预报的回归模型。结果表明,从回归模型分析来看,剔除洪涝年份后,晚稻y和D、M的相关性得到了提高,其回归方程为y=... 详细信息

通过分析衡阳各县晚稻产量与综合气象干旱指数CI值的关系,利用SPSS软件剔除与预报量关系较弱的自变量,建立了CI值对晚稻产量预报的回归模型。结果表明,从回归模型分析来看,剔除洪涝年份后,晚稻y和D、M的相关性得到了提高,其回归方程为y=384.187+0.508M。模型效果检验表明,样本残差服从正态分布;残差散点的分布随机均匀,且大多落在水平直线-2和2之间;标准化残差的正态曲线的均值为0,标准差为0.989,接近标准正态曲线,回归拟合程度高。从模型检验结果来看,利用该模型对2009年各县晚稻产量进行预报,所得结果和实际相比,平均误差为0.428%。

关键词：晚稻综合气象干旱指数CI 产量预报

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Occurrence and fate of endogenous steroid hormones,alkylphenol ethoxylates, bisphenol A and phthalates in municipal sewage treatment systems

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journal of Environmental Sciences 2017年第11期29卷 49-58页

作者： Qian wu james C.w.lam Karen y.Kwok Mirabelle M.P.Tsui Paul K.S.lam State Key Laboratory in Marine Pollution (SKLMP) Department of Biology and Chemistry Research Centre for the Oceans and Human Health Shenzhen Key Laboratory for Sustainable Use of Marine Biodiversity City University of Hong Kong Department of Science and Environmental Studies The Education University of Hong of Kong

Steroid hormones, alkylphenol ethoxylates（APEOs） and phthalic acid esters（PAEs） are emerging endocrine disrupting chemicals（EDCs） that can interfere with the endocrine function in organisms at low concentrations. The occurrence, distribution behavior, removal rate and the fate of 31 target EDCs in sewage treatment plants, which consist of various treatment facilities and receiving water in Hong Kong, were investigated. Estrone,nonylphenol-di-ethoxylate and diethyl phthalate were found to be dominant in each group of influent samples with concentrations ranging from 11–33, 747–3945 and 445–4635 ng/L,respectively. Conversely, progesterone, nonylphenol-mono-ethoxylate and bis（2-ethylhexyl）phthalate were the most abundant in dewatered sludge, with concentrations ranging from 0.9–237, 75–19,743 and 4310–37,016 ng/g（dry weight）. The removal rates of primary sedimentation and disinfection approaches were lower than 30% for most of the chemicals,while those of activated sludge and reverse osmosis were greater than 80% for more than two-thirds of the compounds, noticeably decreasing the estrogenic risk of sewage discharged into the environment. Steroid hormones were removed via biological degradation, while some APEOs and PAEs adsorbed to the sludge. Victoria Harbor poses a low to medium estrogenic risk mainly contributed by estrone and estradiol and deserves attention.

关键词： Endocrine disruptor Steroid hormone Alkylphenol ethoxylate Phthalic acid ester Risk assessment