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Joint channel and carrier frequency offset estimation for multi-user MIMO-OFDM uplink transmissions

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The Journal of China Universities of Posts and Telecommunications 2008年第1期15卷 75-79页

作者： LI jing LIU Pei-zhi sun Hao Wireless Technology Innovation Institute and Key Laboratory of Universal Wireless Communications Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China

This article proposes a new algorithm of joint channel and carrier frequency-offset OCCFO） estimation for multi-user multi-input and multi-output orthogonal frequency division multiplexing （MIMO-OFDM） systems. A least square （LS） channel estimation and a carrier frequency offset （CFO） correlation estimation are combined in this contribution. CFOs are generally estimated using training sequences in a special synchronization timeslot. In this contribution, CFO estimation is further improved by taking advantages of channel estimation based on pilot symbols in traffic timeslots. The CFOs can be first obtained from the primary channel estimation. And then, with the knowledge of the CFOs estimated, channel estimation can be enhanced greatly. Computer simulation results indicate that the proposed JCCFO scheme is of good performance. Besides, the computational complexity is low.

关键词： multi-user MIMO-OFDM joint channel and carrier frequency offset estimation least square correlation

AZIDE-ALKYNE CLICK POLYMERIZATION:AN UPDATE

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Chinese Journal of Polymer Science 2012年第1期30卷 1-15页

作者： Hong-kun Li jing-zhi sun An-jun Qin Ben Zhong Tang MOE Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and Engineering Zhejiang University Hangzhou 310027 China Department of Chemistry Institute of Molecular Functional Materials The Hong Kong University of Science ＆ Technology Clear Water Bay Kowloon Hong Kong China

The great achievements of click chemistry have encouraged polymer scientists to use this reaction in their field. This review assembles an update of the advances of using azide-alkyne click polymerization to prepare functional polytriazoles（PTAs） with linear and hyperbranched *** Cu（I）-mediated click polymerization furnishes 1,4-regioregular PTAs,whereas,the metal-free click polymerization of propiolates and azides produces PTAs with 1,4-regioisomer contents up to 90%.The PTAs display advanced functions,such as aggregation-induced emission,thermal stability,biocompatibility and optical nonlinearity.

关键词： Click polymerization Azide Alkyne Polytriazole Functionality

Effective enhancement of the emission efficiency of tetraphenylporphyrin in solid state by tetraphenylethene modification

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Chinese Chemical Letters 2019年第1期30卷 143-148页

作者： Nan Jiang Yijia Wang Anjun Qin jing zhi sun Ben Zhong Tang MOE Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and Engineering Zhejiang University Guangdong Innovative Research Team State Key Laboratory of Luminescent Materials and Devices South China University of Technology Department of Chemistry Institute for Advanced Study Institute of Molecular Functional Materials and State Key Laboratory of Molecular Neuroscience The Hong Kong University of Science & Technology

Tetraphenylporphyrin(TPP) is a typical red-emitting luminogen showing evident aggregation caused quenching(ACQ) effect. To enhance its emission efficiency in solid state, four tetraphenylethene(TPE)units were attached to the four meso-positions of TPP core via ester group through a facile and efficient route. The derived compound(4(TPE-COO)-TPP) emits red fluorescence(peak at 655 nm) with a good quantum efficiency(F) of 7.5%, which is much higher than that of TPP(Φ～ 0.1%). In molecular aggregate formed in tetrahydrofuran(THF) and water mixtures, 4(TPE-COO)-TPP has a relative high F of 12%. The evidently subdued ACQ behavior can be ascribed to the propeller shape and bulky size of the TPE units,which prevent the close packing and strong p-p interaction of TPP cores. The loose molecular packing and weak interchromophore interactions were validated by different characterization methods including UV-visible absorption, steady state and transient fluorescence spectroscope, X-ray diffraction and scanning electronic microscope observations. It is noted that 4(TPE-COO)-TPP has an emission efficiency of 14.4% in dilute THF solution. This is due to the conjugation break between the TPP and TPE moieties, the rotational and vibrational motions of the phenyl groups cannot quench the fluorescence of 4(TPE-COO)-TPP.

关键词： Aggregation-induced emission Tetraphenylethene Porphyrin Red emission Molecular packing

A More Efficient Synthetic Route to Perylene-porphyrin Arrays

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Chinese Chemical Letters 2003年第11期14卷 1105-1108页

作者： Xin Guo YANG jing zhi sun Mang WANG Hong Zheng CHEN Department of Polymer Science&Engineering State Key Laboratory for Silicon MaterialsZhejiang UniversityHangzhou 310027

We present an efficient synthetic route towards two kinds of perylene-porphyrin arrays. Starting from 5, 10, 15, 20-meso-tetraphenylporphyrin, two novel 9a and 9b were designed and synthesized with 40.3% and 35.1% yi... 详细信息

关键词： Perylene-porphyrin arrays photoinduced charge transfer molecular switch.

The superiority of nonconjugated structures in fluorescence:through-space ***-bond charge transfer

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Science China Chemistry 2024年第9期67卷 3121-3130页

作者： Weihao Tu Zuping Xiong Lei Wang Jianyu Zhang jing zhi sun Haoke Zhang Ben Zhong Tang MOE Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and EngineeringZhejiang UniversityHangzhou 310058China Zhejiang-Israel Joint Laboratory of Self-Assembling Functional Materials ZJU-Hangzhou Global Scientific and Technological Innovation CenterZhejiang UniversityHangzhou 311215China Centre of Healthcare Materials Shaoxing InstituteZhejiang UniversityShaoxing 312000China Department of Chemistry Hong Kong Branch of Chinese National Engineering Research Center for Tissue Restoration and ReconstructionThe Hong Kong University of Science and TechnologyHong Kong 999077China School of Science and Engineering Shenzhen Institute of Aggregate Science and TechnologyThe Chinese University of Hong KongShenzhen(CUHK-Shenzhen)Guangzhou 518172China

Constructing charge transfer(CT)state by introducing donor(D)and acceptor(A)is an efficient strategy to regulate the photophysical properties of luminescent *** CT-type luminophores are built onπ-conjugated fused-ring structures,which always show hybrid CT/locally excited(LE)states and luminescence quenching effect in the aggregate *** this work,eight conjugated biphenyl(BP)and nonconjugated diphenylmethane(DPM)derivatives with different donors and acceptors are synthesized to investigate the CT *** photophysical characterization and theoretical calculation demonstrate that the through-space CT(TSCT)in nonconjugated DA-DPM exhibit superior photophysical performance than the conjugated DA-BP with through-bond CT(TBCT),the main manifestations are as follows:(1)TSCT luminophores produce longer maximum emission wavelength(λ_(em))than the corresponding TBCT *** example,the longest λ_(em)of DMA-CN-DPM(DMA,dimethylamino)is 621 nm but the corresponding λ_(em)of DMA-CN-BP is only 480 nm.(2)TSCT-based DA-DPM demonstrates more sensitive responsiveness to environmental stimuli such as temperature and polarity.(3)Complete separation of the the highest occupied molecular orbital(HOMO)and the lowest unoccupied molecular orbital(LUMO)distribution exists in all kinds of conformation of DA-DPM,which was hard to realize in conjugated DA-BP.

关键词： through-space charge transfer through-space conjugation clusteroluminescence diphenylmethane

The specific detection of Cu(Ⅱ) using an AIE-active alanine ester

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Chinese Chemical Letters 2013年第8期24卷 668-672页

作者： Shuang Zhang Ji-Ming Yan An-Jun Qin jing-zhi sun Ben-Zhong Tang MoE Key Laboratory of Macromolecule Synthesis and Functionalization Department of Polymer Science and EngineeringZhejiang University Department of Chemistry Institute of Molecular Functional Materialsthe Institute for Advanced Study(IAS)The Hong Kong University of Science & Technology

Cu（Ⅱ） detection is important because it plays crucial role in several biological processes and ecological *** techniques have attracted more and more attention in Cu（Ⅱ） *** this report,we contribute a novel strategy to use fluorescence spectroscopy for Cu（Ⅱ） specific *** specificity relies on the fact that,of the many metal cations,only Cu（Ⅱ） can catalyze the hydrolyzation of a-amino acid *** novelty originates from the unique aggregation-induced emission（AIE） property of the fluorescent *** designed a model a-amino acid ester（TPE-Ala） constructed with alanine and tetraphenylethene-functionalized methanol（TPE-methanol）.In comparison with the precursor TPE-Ala, TPE-methanol has lower solubility and is easy to form aggregates in water,thereby displaying a higher fluorescent ***,the Cu（Ⅱ） catalyzed hydrolyzation can be monitored by recording the fluorescence enhancement and fluorescent detection Cu（Ⅱ） is rationally achieved.

关键词： Aggregation-induced emission Fluorescence enhancement Cu(Ⅱ) catalyzed

3,4,5-Triphenyl-1,2,4-triazole-based multifunctional n-type AIEgen

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Science China Chemistry 2017年第5期60卷 635-641页

作者： Yang Shi Yuanjing Cai Yi Jia Wang Ming Chen Han Nie Wei Qin Haoke Zhang jing zhi sun Anjun Qin Ben Zhong Tang Key Laboratory of Macromolecular Synthesis and Functionalization Ministry of Education Department of Polymer Science and EngineeringZhejiang University Guangdong Innovative Research Team State Key Laboratory of Luminescent Materials and Devices South China University of Technology Department of Chemistry Hong Kong Branch of Chinese National Engineering Research Center for Tissue Restoration and ReconstructionThe Hong Kong University of Science & Technology

The luminogens with aggregation-induced emission(AIEgens) characteristics have been widely applied in diverse areas. However,the n-type AIEgens are to be further developed. In this paper, we designed and synthesized an n-type multifunctional AIEgen of tetraphenylethene-substituted 3,4,5-triphenyl-4H-1,2,4-triazole(BTPE-TAZ). This AIEgen can serve as both light-emitting and electron-transporting layers in organic light-emitting devices. Moreover, it also exhibits the interesting optical waveguide and reversible mechanochromic luminescence properties, which are of great potential for practical applications.

关键词： aggregation-induced emission organic light-emitting diodes electron transport optical waveguidc,mechanoehromic luminescence

Proteomic Analysis of the Uterosacral Ligament in Postmenopausal Women with and without Pelvic Organ Prolapse

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Chinese Medical Journal 2015年第23期128卷 3191-3196页

作者： zhi-jing sun Lan Zhu jing-He Lang Zhao Wang Shuo Liang Department of Obstetrics and Gynecology Peking Union Medical College Hospital Peking Union Medical College Chinese Academy of Medical Sciences Beijing 100730 China Core Facility of Instruments Institute of Basic Medical Sciences Chinese Academy of Medical Sciences School of Basic Medicine Peking Union Medical College Beijing 100005 China

Background： Pelvic organ prolapse （POP） is a major health problem in adult women that involves many factors. No proteomic analysis has been conducted exclusively in POP patients. This study aimed to identify the differential expression of proteins that may be involved in POP by proteomic analysis.Methods： Samples of the uterosacral ligament （USL） were collected from five POP patients and five non-POP patients matched according to age, parity, and menopausal status and analyzed using two-dimensional electrophoresis and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry （MALDI-TOF-MS）. Quantitative real-time polymerase chain reaction （qRT-PCR） was used to verify the mRNA expression of proteins that showed differential expression in the proteomic analyses. Results： Proteins differentially expressed between POP and non-POP patients were detected. Eight proteins that were down-regulated in the POP group were identified by MALDI-TOF-MS. These proteins included electron transfer flavoprotein, apolipoprotein A-I, actin, transgelin, cofilin-1, cyclophilin A, myosin, and galectin-1, and their expression was verified by qRT-PCR. Conclusion： Using comparative proteomics, we identified eight differentially expressed proteins （including four cytoskeleton proteins and three proteins related to apoptosis） in the USL that may be involved in apoptosis associated with the tissue effects in POP pathophysiology.

关键词： Apoptosis Cytoskeleton Pelvic Organ Prolapse Proteomics Uterosacral Ligament

Trocar-site hernia after gynecological laparoscopic surgery: a 20-year, single-center experience

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Chinese Medical Journal 2019年第22期132卷 2677-2683页

作者： Ya-Pei Zhu Shuo Liang Lan Zhu zhi-jing sun jing-He Lang Department of Obstetrics and Gynecology Peking Union Medical College HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100730China

Background:Trocar-site hernia(TSH)is a serious complication after laparoscopic *** it is a rare entity,it have life-threatening *** study aimed to retrospectively analyze the potential associated factors for TSH following gynecologic laparoscopy and summarize prevention strategies based on our ***:We searched for gynecological laparoscopic surgeries in the medical records system of Peking Union Medical College Hospital(PUMCH)from August 1998 to July 2018 and further sifted through the results for cases involving *** included patients were divided into different groups according to patient characteristics,and the rate of TSH was compared among ***,the detailed information of all patients with TSH was recorded and *** analyses were performed with GraphPad Prism ***:The approximate total rate of post-operative TSH among gynecologic laparoscopy procedures performed at PUMCH in the last 20 years was 0.016%(9/55,244).The rate of TSH was significant higher in elder patients(>60 years old;3/2686,0.112%)than in younger patients(<60 years old,6/52,558;0.011%,P=0.008).Moreover,the approximate rate of TSH was significantly higher after single-incision laparoscopic surgery(SILS,2/534,0.357%)than conventional laparoscopic surgery(7/54,710,0.013%,P=0.003).The average age of patients with TSH was 53.4 years(range,35.0-79.0 years).Two of the nine patients had late-onset TSH following SILS;the other seven had early-onset TSH following conventional *** TSH cases occurred at right lateral port sites,and the remaining three occurred at the umbilical port *** patients underwent repair surgery,and one required small bowel ***:Older age and SILS are potential associated factors for TSH development,while reducing excessive manipulation and improving suturing skills,especially at the umbilical trocar site following SILS and the right lateral trocar site,can avoid herniation.

关键词： Prevention Risk-factors Single-incision laparoscopic surgery Trocar-site hernia