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基于四苯基乙烯双轴取向发光液晶分子的相结构

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基于四苯基乙烯双轴取向发光液晶分子的相结构

Enhanced thermoelectric properties of SnSe thin films grown by.pulsed laser glancing-angle deposition

2012年两岸三地高分子液晶态与超分子有序结构学术研讨会（暨第十二届全国高分子液晶态与超分子有序结构学术论文报告会）

作者：余振强袁望章林杰生 lam jacky.w.y.唐本忠深圳大学化学与化工学院深圳市功能高分子重点实验室上海交通大学化学与化工学院香港科技大学化学系

传统的有机发光材料在聚集状态下会导致荧光猝灭,而分子聚集或自组装是形成液晶相的内在要求,即发光与液晶之间存在矛盾。四苯基乙烯(TPE)是一类具有聚集诱导发光效应的类盘状分子,将其应用于液晶分子的设计将有望解决发光与液晶之间的... 详细信息

传统的有机发光材料在聚集状态下会导致荧光猝灭,而分子聚集或自组装是形成液晶相的内在要求,即发光与液晶之间存在矛盾。四苯基乙烯(TPE)是一类具有聚集诱导发光效应的类盘状分子,将其应用于液晶分子的设计将有望解决发光与液晶之间的矛盾。本文将二苯乙炔或联苯衍生物等棒状液晶基元连接到TPE上形成对称或不对称的具有双轴取向的发光液晶分子。采用差示扫描量热仪(DSC)、变温一维广角X-射线衍射(1D wAXD)和偏光显微镜等多种表征手段对其本体相结构进行研究。对于四取代的对称性分子,TPE通过分子间堆积形成的柱状结构与棒状液晶基元之间堆积形成的层状结构之间形成双轴取向的层状相结构。对于单取代的非对称性分子,则形成亚稳态的液晶相,随着温度的升高将转变为晶相结构。

关键词：聚集诱导发光四苯基乙烯液晶相结构 X-射线衍射

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Journal of Materiomics 2017年第4期3卷 293-298页

作者： Chun Hung Suen Dongliang Shi y.Su Zhi Zhang Cheuk Ho Chan Xiaodan Tang y.Li Kwok Ho lam Xinxin Chen B.L.Huang X.y.Zhou Ji-y.n Dai Department of Applied Phy.ics The Hong Kong Polytechnic UniversityHung HomKowloonHong KongChina Department of Electrical Engineering The Hong Kong Polytechnic UniversityHung HomKowloonHong KongChina Department of Mechanical and Aerospace Engineering The Hong Kong University of Science and TechnologyClear Water BayKowloonHong KongChina College of Phy.ics Chongqing UniversityChongqing 401331China

SnSe single cry.tals have been demonstrated to possess excellent thermoelectric *** this work,we demonstrate a grain size control method in growing nanocry.talline SnSe thin films through a glancing angle pulsed-laser deposition *** characterization reveals that the SnSe film deposited at a normal angle has a preferred orientation along a axis,while by.contrast,the SnSe film deposited at an 80glancing angle develops a nanopillar structure with the growth direction towards the incident atomic *** glancing angle deposition greatly.reduces the grain size of the thin film due to a shadowing effect to the adatoms,resulting in significantly.increased power factor for more than 100%.The maximum Seebeck coefficient and power factor are 498.5 mV=K and 18.5 mwcm^(-1)K^(-2),*** enhancement of thermoelectric property.can be attributed to the potential barrier scattering at grain boundaries owing to the reduced grain size and increased grain boundaries in the *** this enhanced power factor,and considering the fact that the nanopillar structure should have much lower thermal conductivity.than a plain film,the zT value of such made SnSe film could be significantly.larger than the corresponding single cry.tal film,making it a good candidate for thin film-based thermoelectric device.

关键词： Thermoelectric SnSe Glancing angle Potential barrier scattering

Fine root litter quality.regulates soil carbon storage efficiency.in subtropical forest soils

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Soil Ecology.Letters 2023年第4期5卷 65-80页

作者： Shan Xu Fanglong Su Emma J.Say.r Shu Kee lam Xiankai Lu Chengshuai Liu Derrick y.F.Lai Department of Geography.and Resource Management The Chinese University of Hong KongShatinNew TerritoriesHong Kong SARChina South China Botanical Garden Chinese Academy of SciencesGuangzhou 510070China Lancaster Environment Centre Lancaster UniversityLancasterLA14YQUnited Kingdom Smithsonian Tropical Research Institute P.O.Box 0843-03092BalboaAnconPanamaRepublic of Panama School of Agriculture and Food The University of MelbourneVictoria 3010Australia Guangdong Key.Laboratory.of Integrated Agro-environmental Pollution Control and Management Guangdong Institute of Eco-environmental Science&TechnologyGuangzhou 510650China State Key.Laboratory.of Environmental Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China Centre for Environmental Policy.and Resource Management The Chinese University of Hong KongShatinNew TerritoriesHong Kong SARChina

●High-quality.and low-quality.root litter had contrasting patterns of mass loss.●Greater litter-derived C was incorporated into soils under high-quality.root litter.●Root litter decay.rate or litter-derived C were related to soil microbial diversity.●Root litter quality.had little effect on soil phy.icochemical properties.●High root litter quality.was the main driver of enhanced soil C storage *** root litter is a major contributor to soil carbon(C)storage in forest *** decomposition,the quality.of root litter could play.a critical role in soil C ***,it is unclear whether root litter quality.influences soil C storage *** conducted a two-y.ar greenhouse decomposition experiment using 13C-labeled fine root litter of two tree species to investigate how root litter quality.represented by.C to nitrogen(C/N)ratios,regulates decomposition and C storage efficiency.in subtropical forest soils in China.‘High-quality.root litter(C/N ratio=26)decay.d faster during the first y.ar(0−410 day.),whereas‘low-quality.root litter(C/N ratio=46)decomposed faster toward the end of the two-y.ar period(598−767 day.).However,over the two y.ars of the study.mass loss from high-quality.root litter(29.14±1.42%)was lower than‘low-quality.root litter(33.01±0.54%).Nonetheless,root litter C storage efficiency.i.e.,the ratio of new root litter-derived soil C to total mineralized root litter C)was significantly.greater for high-quality.root litter,with twice as much litter-derived C stored in soils compared to low-quality.root litter at the end of the *** litter quality.likely.influenced soil C storage via changes in microbial diversity.as the decomposition of high-quality.litter declined with increasing bacterial diversity.whereas the amount of litter-derived soil C from low-quality.litter increased with fungal *** results thus reveal that root litter quality.mediates decomposition and C storage in subtropical forest soils in Ch

关键词： fine root litter quality root litter decomposition litter carbon storage efficiency soil organic carbon accumulation subtropical forest

Endohepatology.Arrival at the frontier of interventional endosonography

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world Journal of Gastroenterology 2024年第18期30卷 2397-2401页

作者： Shane P Selvanderan Eric lam Neal Shahidi Department of Medicine University of British ColumbiaVancouver V6Z 1Y6BCCanada

Endohepatology.describes the emerging field where diagnostic and therapeutic endoscopic ultrasound(EUS)are used for the diagnosis and management of liver disease and its *** this editorial we comment on the article by.Gadour et *** spectrum of EUS-guided procedures includes liver parenchy.al and lesional biopsy.abscess drainage,treatment of focal liver lesions,diagnosis of portal hy.ertension and management of gastric *** data suggest that the application of EUS to hepatology.is technically.feasible and safe,heralding the arrival at a new frontier for *** data,specifically.randomised trials comparing EUS to interventional radiology.techniques,and continued partnership between endoscopy.and hepatology.are required to see this field establish itself outside expert tertiary.centres.

关键词： Cancer Cirrhosis Endoscopy Endoscopic ultrasound Liver disease

Contributing to a Healthy.Older Population of the Future: Investigating the Daily.walking Steps of working Adults in Hong Kong

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Journal of Biosciences and Medicines 2015年第9期3卷 22-31页

作者： Linda y. K. Lee Simon C. lam S. L. wong Alisa K. P. wong Chery. C. y. y.ung Division of Nursing and Health Studies The Open University of Hong Kong Hong Kong China

Developing a healthy.lifesty.e during adulthood is one of the essential factors to prepare for healthy.aging. This cross-sectional descriptive study.investigated the daily.walking steps of 893 working adults from nine occupation categories in Hong Kong. Their daily.walking steps were measured using a pedometer. Analy.is of variance (ANOVA) was used to compare the difference in daily.walking steps between participants in different occupation category. Chi-square test was used to compare the difference in proportion of working adults in each occupation category.who walked and did not walk 10,000 steps per day. Results reveal that the participants in average walked 8661 steps per day. “Plant and machine operators and assemblers” and “clerks” were the two least active groups. Participants from the nine occupation categories demonstrated a significant difference in the number of daily.walking steps. Post hoc analy.is revealed a significant difference between “plant and machine operators and assemblers” and “service workers and shop sales workers” (p well as between “plant and machine operators and assemblers” and “craft and related workers” (p who walked and did not walk 10,000 steps per day. Owing to a large difference in number of participants in the nine occupation categories and other study.limitations, further sy.tematic investigation is indicated to confirm the study.results. To summarize, working adults in Hong Kong are only.somewhat active. Identify.ng the factors that deter the working adults from walking and the way. to promote walking among working adults is necessary.to prepare a healthy.older population of the future.

关键词： Pedometer Phy.ical Activity walking working Adults Hong Kong

The Effect of a Visual Memory.Training Program on Chinese Handwriting Performance of Primary.School Students with Dy.lexia in Hong Kong

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Open Journal of Therapy.and Rehabilitation 2015年第4期3卷 146-158页

作者： Cecilia w. P. Li-Tsang Agnes S. K. wong Linda F. L. Tse Hebe y. H. lam Viola H. L. Pang Cathy.y. F. Kwok Maggie w. S. Lin Department of Rehabilitation Sciences The Hong Kong Polytechnic University Hong Kong China

This study.investigated the effect of a visual memory.training program on Chinese handwriting performance among primary.school students with dy.lexia in Hong Kong. Eight students of Grade 2 to 3 who were diagnosed with dy.lexia were recruited. All participants received six sessions of training, which composed of 30-minute computerized game-based visual memory.training and 30-minute Chinese character segmentation training. Visual perceptual skills and Chinese handwriting performance were assessed before and after the training, as well as three weeks after training using the Test of Visual Perceptual Skills (3rd edition) (TVPS-3) and the Chinese Handwriting Analy.is Sy.tem (CHAS). In comparing the pre- and post-training results, paired t-tests revealed significant improvements in visual memory.skills, as well as handwriting speed, pause time and pen pressure after the training. There was no significant improvement in handwriting accuracy.or legibility. The improved visual memory.and handwriting performance did not show a significant drop at the follow-up assessments. This study.showed promising results on a structured program to improve the Chinese handwriting performance, mainly.in speed, of primary.school children. The improvements appeared to be well-sustained after the training program. There is a need to further study.the long-term effect of the program through a randomized controlled trial study.

关键词： Visual Memory Handwriting Dy.lexia Primary School Students Chinese

含二苯炔基元的侧链液晶聚炔的合成、性能及结构

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含二苯炔基元的侧链液晶聚炔的合成、性能及结构

Evaluation of Growth and Quality.in Latuca Sativa L. under Different Photoperiods

2015年全国高分子学术论文报告会

作者：余振强李婷婷李少军 lam jacky.w.y. 唐本忠深圳大学化学与化工学院深圳市功能高分子重点实验室香港科技大学深圳研究院香港科技大学化学系

单取代侧链液晶聚炔的本体相结构研究表明,当主链为顺式构型时,分子形成刚性柱状结构,进而堆砌形成柱状液晶相;当主链为反式构型时,较短的间隔基使刚性主链和侧链液晶基元之间耦合形成片状结构,可以堆砌形成分子间排列受挫的高级有序近... 详细信息

单取代侧链液晶聚炔的本体相结构研究表明,当主链为顺式构型时,分子形成刚性柱状结构,进而堆砌形成柱状液晶相;当主链为反式构型时,较短的间隔基使刚性主链和侧链液晶基元之间耦合形成片状结构,可以堆砌形成分子间排列受挫的高级有序近晶相。如果侧链基元为具有发光性能的液晶基元,形成的近晶相结构在取向后将有望发射高偏振度的线偏振光。本文在合成一系列具有不同长度间隔基和不同长度烷基尾链的含二苯炔基元的侧链液晶聚炔的基础上,通过紫外-可见分光光度法、荧光（偏振）光谱、差示扫描量热法（DSC）、变温一维和二维（1D和2D）广角X-射线衍射（wAXD）、偏光显微镜（PLM）等研究手段考察聚合物及其单体的发光行为及相结构,并采用分子动力学方法模拟其液晶相结构。结果表明,二苯炔可以作为液晶基元引入聚炔侧链形成具有发光性能的侧链液晶聚炔,在样品取向后能够产生高偏振度的线偏振光。

关键词：聚炔二苯炔发光偏振

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当代农业（中英文版） 2016年第2期5卷 8-12页

作者： K.w.lam J.C.w.Pang K.H.Loo y.M.Lai S.y.Chau Department of Electronic and Information Engineering The Hong Kong Polytechnic University Hong Kong SAR China Pong y.en Holdings Limited Hong Kong SAR China

1-((12-Bromododecy.)oxy.-4-((4-(4-penty.cy.lohexy.) pheny.)ethy.y.) benzene：Liquid cry.tal with aggregation-induced emission characteristics

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中国科学：化学 2013年第9期43卷 1204-1204页

作者： CHEN y.Fei LIN JieSheng y.AN wangZhang y. ZhenQiang lam jacky.w.ngy.p TANG BenZhong Shenzhen Key.Laboratory.of Functional Poly.ers School of Chemistry and Chemical Engineering Shenzhen University Shenzhen 518060 China National Institutes for Food and Drug Control Beijing 100050 China School of Chemistry.and Chemical engineering Shanghai Jiao Tong University Shanghai 200240 China Department of Chemistry The Hong Kong University of Science & Technology Clear Water Bay Kowloon Hong Kong China

The luminescent liquid cry.tals(LLCs)are expected to solve the conflicts between the aggregation caused quenching and the requirement of aggregation or self-organization for ***,we developed a new strategy.of apply.ng aggregation-induced emission(AIE)phenomenon to the molecular design of LCs towards *** this report,a calamitic liquid cry.tal based on tolane with AIE characteristics was successfully.sy.thesized and the chemical structure was characterized by.H,13C NMR,and matrix-assisted laser desorption/ionization time-of-flight(MALDI-TOF)high-resolution mass *** fluorescence behavior was studied by.fluorescence spectroscopy.and the liquid cry.tal phase behaviors were investigated by.differential scanning calorimetry.DSC),polarized optical microscopy.POM).The cry.tal structure was obtained by.X-ray.diffraction cry.tallography.with P1 space *** demonstrated that the sample was AIE active and the LC phases sequence during cooling was nematic,smectic C and smectic B phase.

关键词：液晶发射特性诱导聚合乙炔基环己基 MALDI-TOF 基质辅助激光解吸