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Photodegradation-Induced Turn-On Luminescence of Tetraphenylethylene-Based Trithiocarbonate Polymers

Chinese Journal of Chemistry 2021年第10期39卷 2837-2842页

作者： Hanchen Shen wenjie wu Shunjie Liu Jing Zhang jacky wyLam Ben Zhong Tang Department of Chemistry Hong Kong Branch of Chinese National Engineering Research Center for Tissue Restoration and Reconstruction and Institute of Advanced StudyThe Hong Kong University of Science and TechnologyClear Water BayKowloonHong KongChina Department of Laboratory Medicine Nanfang HospitalSouthern Medical UniversityGuangzhouGuangdong 510515China HKUST Shenzhen Research Institute No.9 Yuexing 1 st RDSouth Area Hi-tech ParkNanshanShenzhenGuangdong518057 China Center for Aggregation-induced Emission SCUT-HKUST Joint Research InstituteState Key Laboratory of Luminescent Materials and DevicesSouth China University of TechnologyGuangzhouGuangdong510640 China HKUST AIE Institute Guangzhou Development DistrictHuangpuGuangzhouGuangdong510530 China Guangdong-Hong Kong-Macao Joint laboratory of Optoelectronic and Magnetic Functional Materials The Hong Kong University of Science and TechnologyClear Water BayKowloonHong KongChina

Main observation and conclusion Fluorescent intelligent materials have attracted wide attention because of their great potential *** major hurdle for the development and application of fluorescent intelligent materials is the aggregation-caused quenching effect in the solid ***,tetraphenylethylene-based trithiocarbonate polymers with satisfactory molecular weights(Mw up to 24900)were synthesized through a one-pot polymerization route under mild *** polymers were non-emissive due to the quenching effect of the trithiocarbonate ***,upon UV irradiation,the polymers degraded and strong emission from the tetraphenylethylene unit was *** a unique property endows them with great potential applications,such as photopatterning,anti-counterfeit labels,and UV detection.

关键词： Photochemistry Trithiocarbonate polymers Luminescence Polymerization Aggregation-induced emission

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Static and dynamic evaluations of acoustic positioning system using TDMA and FDMA for robots operating in a greenhouse

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International Journal of Agricultural and Biological Engineering 2022年第5期15卷 28-33页

作者： Lok wai jacky Tsay Tomoo Shiigi Xunyue Zhao Zichen Huang Keiichiro Shiraga Tetsuhito Suzuki yuichi Ogawa Naoshi Kondo Laboratory of Bio-Sensing Engineering Division of Environmental Science and TechnologyGraduate School of AgricultureKyoto UniversityKyoto 606-8502Japan Department of Ocean Mechanical Engineering National Fisheries UniversityShimonoseki 759-6595Japan

Acoustic positioning system has great potential to be applied in a greenhouse due to its centimeter-level accuracy,low cost,and ability of extensive greenhouse *** Spectrum Sound-based local positioning system(SSSLPS)was proposed to be a navigation tool for multiple agricultural robots by the authors'research ***,to increase the system capacity for positioning multiple robots in a greenhouse,the near-far problem caused by the interference between speakers needs to be *** use of different access methods,Time Division Multiple Access(TDMA)or Frequency Division Multiple Access(FDMA),is essential in the SSSLPS system for solving the near-far *** static positioning in a greenhouse was first evaluated by setting different parameters to determine the optimal signal setting for a dynamic *** that,the moving robot tests were added with a motion capture system and tested the performance of TDMA and *** results demonstrated that TDMA can be used in a stationary sound-based positioning system with 12.2 mm accuracy,but it has a time delay problem in dynamic positioning.A simulation was designed to mimic the position error increases with different moving *** FDMA has the sound damping problem in high-frequency regions creating a peak detection issue,it achieved a higher accuracy with an average position error of 62.1 mm compared to 180.3 mm of *** study shows that the TDMA method is suitable for static measurements,while the FDMA method is suitable for measuring dynamic objects and controlling mobile robots.

关键词： greenhouse robots positioning system near-far problem TDMA FDMA

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Red-emitting salicylaldehyde Schiff base with AIE behaviour and large Stokes shift

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Chinese Chemical Letters 2018年第10期29卷 1493-1496页

作者： Junyi Gong Peifa wei yuanan Su ying Li Xing Feng jacky w.y.Lam Dongzhou Zhang Xiangzhi Song Ben Zhong Tang College of Chemistry and Chemical Engineering Central South University Department of Chemistry Hong Kong Branch of Chinese National Engineering Research Center for Tissue Restoration and ReconstructionDivision of Life Science and Division of Biomedical EngineeringThe Hong Kong University of Science and Technology Partnership for Extreme Crystallography Hawaii Institute of Geophysiscs and PlanetologyUniversity of Hawaii at Manoa

Three salicylaldehyde Schiff base（SSB）, iso-PBP, PBP and EPB, were facilely synthesized and exhibited aggregation-induced emission. The introduction of C= N-N = C moiety in these SSB dyes largely extend the conjugation system and push their emission to yellow to red spectral region. These SSB dyes were negligibly fluorescent in dilute THF solution. In THF/water mixtures with high water fractions, they displayed strong yellow to red fluorescence（up to 617nm） and large Stokes shifts（up to 152 nm）. Single crystal analysis on EBP showed the longer emission of in aggregated state was attributed to the molecular packing effect as compared with that in dilute solution. The bio-imaging application indicated EBP could specifically accumulate in lipid droplets in living cells.

关键词： Aggregation-induced emission Salicylaldehyde Schiff base Red-emitting ESIPT Aldehyde-amine condensation

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Anharmonic electron-phonon coupling in ultrasoft and locally disordered perovskites

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npj Computational Materials 2023年第1期9卷 744-756页

作者： Marios Zacharias George Volonakis Feliciano Giustino jacky Even Univ Rennes INSA RennesCNRSInstitut FOTON-UMR 6082F-35000 RennesFrance Univ Rennes ENSCRINSA RennesCNRSISCR-UMR 6226F-35000 RennesFrance Oden Institute for Computational Engineering and Sciences The University of Texas at AustinAustinTX 78712USA Department of Physics The University of Texas at AustinAustinTX 78712USA

Anharmonicity and local disorder(polymorphism)are ubiquitous in perovskite physics,inducing various phenomena observed in scattering and spectroscopy *** of these phenomena still lack interpretation from first principles since,hitherto,no approach is available to account for anharmonicity and disorder in electron–phonon ***,relying on the special displacement method,we develop a unified treatment of both and demonstrate that electron–phonon coupling is strongly influenced when we employ polymorphous perovskite *** uncover that polymorphism in halide perovskites leads to vibrational dynamics far from the ideal noninteracting phonon picture and drives the gradual change in their band gap around phase transition *** also clarify that combined band gap corrections arising from disorder,spin-orbit coupling,exchange–correlation functionals of high accuracy,and electron–phonon coupling are all *** findings agree with experiments,suggesting that polymorphism is the key to address pending questions on perovskites’technological applications.

关键词： perovskite phonon harmonic

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AMD K6—3 400MHz CPU

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微型计算机 1999年第3期19卷 38-40页

作者： jacky

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具有不同长度间隔基的含联苯基团的侧链液晶聚炔的荧光行为(英文)

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物理化学学报 2010年第8期26卷 2281-2285页

作者：余振强张昕李子臣陈尔强 LAM jacky w. y. 唐本忠北京大学化学与分子工程学院高分子科学与工程系高分子化学与物理教育部重点实验室北京分子科学国家实验室北京100871 深圳大学化学与化工学院深圳市功能高分子重点实验室广东深圳518060 香港科技大学化学系香港九龙

对一系列具有不同长度间隔基的含联苯基团的侧链液晶聚炔的稳态荧光和荧光衰减行为进行了研究.为便于比较,选取其中一个单体作为模型化合物.稳态荧光光谱结果表明,聚合物和单体均显示一个荧光发射,该荧光发射来源于聚合物侧链的联苯基团... 详细信息

对一系列具有不同长度间隔基的含联苯基团的侧链液晶聚炔的稳态荧光和荧光衰减行为进行了研究.为便于比较,选取其中一个单体作为模型化合物.稳态荧光光谱结果表明,聚合物和单体均显示一个荧光发射,该荧光发射来源于聚合物侧链的联苯基团.随着间隔基长度的减小,聚合物的荧光强度降低.荧光衰减结果表明单体的荧光衰减可以拟合为一个单指数衰减,而聚合物的荧光衰减拟合为三指数衰减.这种三指数衰减可能由溶液局部高浓度引起的猝灭和侧链联苯基团的旋转受阻所引起.溶剂效应表明,溶剂与联苯基团之间的相互作用随溶剂极性增加而增大.

关键词：稳态荧光单取代聚炔联苯荧光寿命溶剂效应

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Crystalline Behavior and Structure of a Liquid Crystal Com- pound, 5-{[4＇-（（（Pentyl）oxy）-4-biphenylyl）carbonyl]oxy}- 1 -pentyne

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Chinese Journal of Chemistry 2011年第4期29卷 631-638页

作者：刘雷静李杲周恩乐 Lam,jacky wing yip 唐本忠 State Key Laboratory of Supramolecular Structure and Materials Jilin University Changchun Jilin 130012 China State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences Graduate School of Chinese Academy of Sciences Changchun Jilin 130022 China Department of Chemistry Hong Kong University of Science & Technology Clear Water Bay Kowloon Hong Kong China

Single crystals of two liquid crystal compounds, 5-{[4＇-（（（pentyl）oxy）-4-biphenylyl）carbonyl]oxy}-1-pentyne （A3EO5） and 5-{[（4＇-nonyloxy-4-biphenylyl）carbonyl]oxy}-1-pentyne （A3EO9）, have been prepared by solution growth technique. The morphologies and structures of A3EO5 and A3EO9 crystals were investigated by wide angle X-ray diffraction （wXRD）, atom force microscope （AFM） and transmission electron microscope （TEM）. In contrast to the same series of compounds which have a longer alkyl tail, 5-{[（4＇-heptoxy-4-biphenylyl）carbonyl]oxy}-1-pentyne （A3EO7）, 5-{[（4＇-heptoxy-4-biphenylyl）oxy]carbonyl}-1-pentyne （A3E＇O7） and A3EO9, A3EO5 shows strikingly different crystalline behavior. The former three compounds have only one crystal form, whereas A3EO5 exhibits polymorphism. Specifically, A3EO5 crystals grown from toluene solution show two crys- tal forms. The first one is crystal I which adopts a monoclinic P112/m space group with unit cell parameters of a= 5.79A, b=8.34A, c=43.92/k, y=96°, and the other one is crystal II which adopts a monoclinic P112 space group with unit cell parameters of a=5.55A, b=7.38A, c=31.75 ]k, y=94°. when using dioxane as the solvent to grow A3EO5 crystal, we can selectively obtain crystal Ⅰ. A3EO5 melt-grown crystals also have two crystal forms which derive from crystal I and crystal Ⅱ, respectively. The different crystalline behavior of the compounds should correlate with their different electron dipole moment resulting from the different length of alkyl tail.

关键词： crystal growth crystal morphology crystal structure electron diffraction single crystal

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Prospective case series on trabecular-iris angle status after an acute episode of phacomorphic angle closure

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International Journal of Ophthalmology(English edition) 2013年第1期6卷 67-70页

作者： jacky Lee Jimmy Lai Doris yick Can yuen Department of Ophthalmology University of Hong Kong Department of Ophthalmology Caritas Medical Centre

AIM:To investigate the trabecular-iris angle with ultrasound biomicroscopy (UBM) post cataract extraction after an acute attack of phacomorphic angle closure. ·METHODS:This prospective study involved 10 cases of phacomorphic angle closure that underwent cataract extraction and intraocular lens insertion after intraocular pressure (IOP) lowering. Apart from visual acuity and IOP, the trabecular-iris angle was measured by gonioscopy and UBM at 3 months post attack. ·RESULTS:In 10 consecutive cases of acute phaco-morphic angle closure from December 2009 to December 2010, gonioscopic findings showed peripheral anterior synechiae (PAS) ≤90° in 30% of phacomorphic patients and a mean Shaffer grading of (3.1±1.0). UBM showed a mean angle of (37.1°±4.5°) in the phacomorphic eye with the temporal quadrant being the most opened and (37.1°±8.0°) in the contralateral uninvolved eye. The mean time from consultation to cataract extraction was (1.4 ± 0.7) days and the mean total duration of phacomorphic angle closure was (3.6 ±2.8) days but there was no correlation to the degree of angle closure on UBM (Spearman correlation P =0.7). The presenting mean IOP was (50.5±7.4) mmHg and the mean IOP at 3 months was (10.5±3.4) mmHg but there were no correlations with the degree of angle closure (Spearman correlations P =0.9). CONCLUSION:Anopentrabecular-irisangleandnormal IOP can be achieved after an acute attack of pha-comorphic angle closure if cataract extraction is performed within 1 day-2 days after IOP control. Gonioscopic findings were in agreement with UBM,which provided a more specific and object angle measurement. The superior angle is relatively more narrowed compared to the other quadrants. All contralateral eyes in this series had open angles.

关键词： angle ultrasound biomicroscopy phacomorphic intraocular pressure

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Factors Associated with SARS-CoV-2 Repeat Positivity—Beijing,China,June–September 2020

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China CDC weekly 2022年第5期4卷 88-95,I0006-I0010页

作者： Siqi Li Xiaoli wang Li Li yang Pan Siyuan yang Dawei Tan ying Shen Peng yang Naor Bar-Zeev yaling Hu jacky MJennings Simin Li Linghang wang Quanyi wang Beijing Center for Disease Prevention and Control BeijingChina Department of International Health Johns Hopkins Bloomberg School of Public HealthBaltimoreMDUSA Beijing Municipal Key Laboratory of Clinical Epidemiology BeijingChina School of Public Health Capital Medical UniversityBeijingChina Emergency department of Infectious diseases Beijing Ditan HospitalCapital Medical UniversityBeijingChina Laboratory of Infectious Diseases Center of Beijing Ditan Hospital Capital Medical UniversityBeijingChina Sinovac Biotech Co LtdBeijingChina Department of Pediatrics Johns Hopkins School of MedicineBaltimoreMDUSA yiducloud(Beijing)Technology Co. LtdBeijingChina

Introduction:Repeat positive severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)following COVID-19 initial viral clearance(repositivity)poses a public health management *** objective was to determine factors associated with neutralizing antibody(Nab)level and re-positivity among patients infected with a single strain ***:During a single strain SARS-CoV-2 cluster in Beijing,China,longitudinal individual clinical,virological,and immunological data were collected from 368 infections from June 13 to September 22,*** associated with Nab level and re-positivity were analyzed using generalized estimating ***:A total of 353(96%)SARS-CoV-2 infections had demographic,clinical,and laboratory data *** the 353 infections,55(15.5%)were re-positive,and blood draws were taken from 346 individuals(98.0%)during hospitalization and/or during the follow-up *** were milder for the second-time admission for the re-positives,although 36.4%of re-positives presented with radiographic appearance of pneumonia *** to non-re-positive patients,NAb titers were lower among re-positives;NAb was positively associated with clinical *** from the lower respiratory tract manifested higher viral load than that from the upper respiratory *** analysis showed re-positivity was positively associated with being female[odd ratio(OR)=1.7,95%confidence interval(CI)1.1–2.8]and being agedyears(OR=5.2,95%CI 1.5–18.1);having initially asymptomatic infection(OR=13.7,95%CI 1.6–116.3);and negatively associated with a higher NAb level(OR=0.9,95%CI 0.5–1.7).Conclusions:NAb may be important for sustained viral *** respiratory tract infection was associated with higher viral load among all infections when compared to upper respiratory tract *** lower respiratory and intermittent upper respiratory viral shedding among COVID-19 infections may occur.

关键词： sustained initially neutral

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Revisiting an ancient inorganic aggregation-induced emission system:An enlightenment to clusteroluminescence

Aggregate

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Aggregate 2021年第2期2卷 127-135页

作者： Zheng Zhao Zaiyu wang Javad Tavakoli Guogang Shan Jianyu Zhang Chen Peng yu Xiong Xuepeng Zhang Tsz Shing Cheung youhong Tang Bolong Huang Zhaoxun yu jacky w.y.Lam Ben Zhong Tang Department of Chemistry Hong Kong Branch of Chinese National Engineering Research Center for Tissue Restoration and Reconstruction and Institute for Advanced StudyThe Hong Kong University of Science and TechnologyClear Water BayKowloonHong Kong SARChina School of Chemistry and Chemical Engineering Southeast UniversityNanjingChina Centre for Health Technologies School of Biomedical EngineeringUniversity of Technology SydneySydneyNew South WalesAustralia HKUST Shenzhen Research Institute ShenzhenGuangdongChina College of Science and Engineering Flinders UniversityAdelaideSouth AustraliaAustralia Department of Applied Biology and Chemical Technology The Hong Kong Polytechnic UniversityHung HomKowloonHong Kong SARChina Micro-X Ltd TonsleySouth AustraliaAustralia Guangdong-Hong Kong-Macao Joint Laboratory of Optoelectronic and Magnetic Functional MaterialsGuangdong-Hong Kong-Macao China

Organic and inorganic clusteroluminescence have attracted great attention while the underlying mechanisms is still not well ***,we employed a series of ancient inorganic complexes platinocyanides with aggregation-induced emission property to elucidate the mechanism of clusteroluminescence including how does the chromophore form and how does the solid structures influence the luminescence *** results indicate that the isolated platinocyanide cannot work as a chromophore to emit visible light,while their clusterization at aggregate state can trigger the d-orbitals coupling of the platinum atoms to facilitate the electron exchange and delocalization to form a new chromophore to emit visible ***,the counter ions and H2O ligands help to rigidify the three-dimensional network structure of the platinocyanides to suppress the excited state nonradiative decay,resulting in the high quantum yield of up to 96%.This work fundamentally helps understanding both the organic and inorganic clusteroluminescence phenomenon.

关键词： aggregation-induced emission clusteroluminescence radioluminescence

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