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Mechanistic connotations of restriction of intramolecular motions(RIM)

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National Science Review 2021年第6期8卷 10-13页

作者： yujie Tu Zheng Zhao Jacky W.y.lam Ben Zhong Tang Department of Chemistry Hong Kong Branch of Chinese National Engineering Research Center for Tissue Restoration and ReconstructionInstitute for Advanced Study and Department of Chemical and Biological EngineeringThe Hong Kong University of Science and Technology Center for Aggregation-Induced emission SCUT-HKUST Joint Research InstituteState Key Laboratory of Luminescent Materials and DevicesSouth China University of Technology AIe Institute Guangzhou Development District Ming Wai Lau Centre for Reparative Medicine Karolinska Institutet

Molecules are all in constant motions,which influence their properties. For example, in photophysics, the light emission behavior of a luminogen is determined by its electronic and nuclear motions in the excited state. Flexible molecular motions usually favor nonradiative decay along with the transformation of excited-state energy to other forms such as thermal energy. Therefore,the restriction of intramolecular motions(RIM) is commonly adopted to achieve luminescent materials with high emission brightness.

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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

Amine-cataly.ed polycyclotrimerization of ary.ene bipropiolate:A metal-free and regioselective route to hy.erbranched poly.er

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Science China Chemistry 2008年第8期51卷 705-708页

作者： JIM Cathy K W lam Jacky W y HAeUSSLeR Matthias Department of Chemistry The Hong Kong University of Science & TechnologyClear Water BayKowloonHong KongChina

This paper presents a new synthetic route to hy.erbranched poly.er. An ary.ene bipropiolate monomer,dimethylmethy.enebis(1,4-pheny.ene) bipropiolate,was prepared by a one-step esterification reaction of bisphenol A with propiolic acid. Polycyclotrimrtization of the monomer was effected by reflux in dimethylformamide(DMF),producing a soluble hy.erbranched poly(aroxycarbonylpheny.ene) in a good y.eld. The poly.er was perfectly branched with a degree of branching of 100%.

关键词： cyclotrimerization regioselectivity hy.erbranched poly.er

Mechanistic links between gut microbial community dynamics, microbial functions and metabolic health

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World Journal of Gastroenterology 2014年第44期20卷 16498-16517页

作者： Connie Wy Ha yan y lam Andrew J Holmes School of Molecular Bio-science and Charles Perkins Centre The University of Sydney Pennington Biomedical Research Center

Gut microbes comprise a high density, biologically active community that lies at the interface of an animal with its nutritional environment. Consequently their activity profoundly influences many aspects of the physiology and metabolism of the host animal. A range of microbial structural components and metabolites directly interact with host intestinal cells and tissues to influence nutrient uptake and epithelial health. endocrine, neuronal and lymphoid cells in the gut also integrate signals from these microbial factors to influence systemic responses. Dysregulation of these host-microbe interactions is now recognised as a major risk factor in the development of metabolic dysfunction. This is a two-way process and understanding the factors that tip host-microbiome homeostasis over to dysbiosis requires greater appreciation of the host feedbacks that contribute to regulation of microbial community composition. To date, numerous studies have employed taxonomic profiling approaches to explore the links between microbial composition and host outcomes(especially obesity and its comorbidities), but inconsistent host-microbe associations have been reported. Available data indicates multiple factors have contributed to discrepancies between studies. These include the high level of functional redundancy in host-microbiome interactions combined with individual variation in microbiome composition; differences in study design, diet composition and host system between studies; and inherent limitations to the resolution of r RNA-based community profiling. Accounting for these factors allows for recognition of the common microbial and host factors driving community composition and development of dysbiosis on high fat diets. New therapeutic intervention options are now emerging.

关键词： Microbiome Dysbiosis High fat diet Bile Intestinal mucosa Microbe-associated molecular patterns Short chain fatty acids Immunomodulation enteroendocrine cells

Restriction of Intramolecular Motion(RIM):Investigating AIe Mechanism from experimental and Theoretical Studies

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Chemical Research in Chinese Universities 2021年第1期37卷 1-15页

作者： ZHANG Jianyu ZHANG Haoke lam Jacky W.y. TANG Ben Zhong Department of Chemistry Hong Kong Branch of Chinese National Engineering Research Centre for Tissue Restoration and ReconstructionInstitute for Advanced Studyand Department of Chemical and Biological EngineeringThe Hong Kong University of Science&TechnologyClear Water BayKowloonHong KongP.R.China MOe Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and EngineeringZhejiang UniversityHangzhou310027P.R.China Center for Aggregation-Induced emission SCUT-HKUST Joint Research InstituteState Key Laboratory of Luminescent Materials and DevicesSouth China University of TechnologyGuangzhou510640P.R.China Guangzhou Development District AIE InstituteGuangzhou510530P.R.China

Mechanistic studies promote scientific development from phenomena to ***-induced emission(AIe),as an unusual photophysical phenomenon,builds the bridge between molecular science and aggregate *** the twenty-year development of AIe,restriction of intramolecular motion(RIM)has been verified as the working mechanism of AIe *** this review,these mechanistic works about RIM are summarized from experimental and theoretical ***,the experimental studies are introduced from three parts:external rigidification,structural modification and structural *** the theoretical part,calculations on the low-frequency motion of AIegens have been performed to prove the RIM *** virtue of the theoretical calculations,some new mechanisms are proposed to supplement the RIM,such as restriction of access to conical intersection,suppression of Kasha transition,restriction of access to dark state,*** is foreseeable that the RIM mechanism will unify the photophysical theories for both molecules and aggregates,and inspire more progress in aggregate science.

关键词： Aggregation-induced emission(AIe) Restriction of intramolecular motion Photophysical mechanism Aggregate science

CARBAZOLe-CONTAINING Hy.eRBRANCHeD POLy(ARy.eNeeTHyNy.eNe)S:SyNTHeSIS,CHARACTeRIZATION,ANDPROPeRTIeS

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Chinese Journal of Poly.er Science 2007年第6期25卷 641-649页

作者： Han Peng Xiu-wen Zheng Jacky W. y. lam Ben-zhong Tang Institute of Material Science and engineering South China University of Technology Guangzhou 510640 China Department of Chemistry Hong Kong University of Science ＆ Technology Clear Water Bay Kowloon Hong Kong China

New hy.erbranched poly（ary.eneethyny.ene）s containing carbazole moieties are synthesized in high y.elds （up to 87%） by polycyclotrimerization of 3,6-bis（4-ethynylphenyl）-9-octylcarbazole and its copoly.erization with 1-octy.e cataly.ed by CpCo（CO）2 in THF. The structures and properties of the poly.ers are characterized and evaluated by IR, NMR, TGA, UV, photoluminescence, and cyclic voltammetry analy.es. All the poly.ers are soluble in common organic solvents and show outstanding thermal stability （≥ 430℃）. They graphitize in high y.elds （up to 79%） when pyroly.ed at 800℃. Upon photoexcitation, the poly.ers emit a strong deep blue light of ca. 400 nm with quantum y.elds larger than 60%.

关键词： Acety.enes Carbazole Cyclopoly.erization Hy.erbranched Luminescence.

SyNTHeSIS OF A Hy.eRBRANCHeD POLy(AROyLARy.eNe) CONTAINING TRIAZOLe AND FLUOReNe FUNCTIONALITIeS By CLICK CHeMISTRy AND MeTAL-FRee,ReGIOSeLeCTIVe POLyCyCLOTRIMeRIZATION

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Chinese Journal of Poly.er 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 Poly.er Science and engineering Key Laboratory of Macromolecular Synthesis and Functionalization of Ministry of EducationZhejiang University

A new bis(aroylacety.ene) containing tfiazole and fluorene moieties is synthesized by click chemistry. Polycyclotrimerization of the monomer is cataly.ed by piperidine in refluxed dioxane,furnishing a regioregular poly(aroylary.ene) in a satisfactory *** hy.erbranched structure of the poly.er is characterized spectroscopically with satisfactory *** poly.er 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 Hy.erbranched poly.er.

Answering Reachability Queries on Incrementally Updated Graphs by Hierarchical Labeling Schema

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Journal of Computer Science & Technology 2016年第2期31卷 381-399页

作者： Tak-lam Wong Department of Mathematics and Information Technology The Hong Kong Institute of Education Hong Kong China

We proposed a novel solution schema called the Hierarchical Labeling Schema （HLS） to answer reachability queries in directed graphs. Different from many.existing approaches that focus on static directed acyclic graphs （DAGs）, our schema focuses on directed cyclic graphs （DCGs） where vertices or arcs could be added to a graph incrementally. Unlike many of the traditional approaches, HLS does not require the graph to be acyclic in constructing its index. Therefore, it could, in fact, be applied to both DAGs and DCGs. When vertices or arcs are added to a graph, the HLS is capable of updating the index incrementally instead of re-computing the index from the scratch each time, making it more efficient than many other approaches in the practice. The basic idea of HLS is to create a tree for each vertex in a graph and link the trees together so that whenever two vertices are given, we can immediately know whether there is a path between them by referring to the appropriate trees. We conducted extensive experiments on both real-world datasets and synthesized datasets. We compared the performance of HLS, in terms of index construction time, query processing time and space consumption, with two state-of-the-art methodologies, the path-tree method and the 3-hop method. We also conducted simulations to model the situation when a graph is updated incrementally. The performance comparison of different algorithms against HLS on static graphs has also been studied. Our results show that HLS is highly competitive in the practice and is particularly useful in the cases where the graphs are updated frequently.

关键词： graph indexing reachability query Hierarchical Labeling Schema (HLS) incremental update directed cyclic graph

Ground movements due to deep excavations in Shanghai： Design charts

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Frontiers of Structural and Civil engineering 2014年第3期8卷 201-236页

作者： Malcolm D. BOLTON sze-y.e lam Paul J. VARDANeGA Charles W. W. NG Xianfeng MA Department of engineering University of Cambridge Cambridge CB2 1PZ United Kingdom Advanced Geomechanics Perth Western Australia 6009 Australia Department of Civil engineering University of Br&tol Bristol BS8 1TR United Kingdom Department of Civil and environmental engineering The Hong Kong University of Science and Technology Hong Kong China Key Laboratory of Geotechnical and Underground engineering of Ministry of education Tong/i University Shanghai 200092China

Recent research has clarified the sequence of ground deformation mechanisms that manifest themselves when excavations are made in soft ground. Furthermore, a new framework to describe the deformability of clays in the working stress range has been devised using a large database of previously published soil tests. This paper aims to capitalize on these advances, by analyzing an expanded database of ground movements associated with braced excavations in Shanghai. It is shown that conventional design charts fail to take account either of the characteristics of soil deformability or the relevant deformation mechanisms, and therefore introduce significant scatter. A new method of presentation is found which provides a set of design charts that clarify the influence of soil deformability, wall stiffness, and the geometry of the excavation in relation to the depth of soft ground.

关键词： Shanghai excavations mobilizable strength design dimensionless groups design charts