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Double [5]carbohelicene: facile synthesis, chiroptical properties,isomerization study, and lasing application

Science China Chemistry 2025年第1期 233-240页

作者： Peipei Liu Yantong Li Meng-Xiang Wu Hao Kang Xiao-Li Zhao Lin Xu Linlin Liu Xiaodong Li Junfeng Fang Zhiwei Fang Ya Cheng hai-Bo yang Huakang Yu Xueliang Shi State Key Laboratory of Petroleum Molecular & Process Engineering Shanghai Key Laboratory of Green Chemistry and Chemical ProcessesSchool of Chemistry and Molecular Engineering East China Normal University School of Physics and Optoelectronics South China University of Technology Institute of Polymer Optoelectronic Materials & Devices State Key Laboratory of Luminescent Materials & Devices South China University of Technology School of Physics and Electronic Science Engineering Research Center of Nanophotonics & Advanced Instrument Ministry of EducationEast China Normal University State Key Laboratory of Precision Spectroscopy School of Physics and Electronic Science East China Normal University

Double carbohelicenes have attracted considerable attention due to their aesthetic structures, distinct π-conjugation extension, inherent chirality, and intriguing optical and electronic properties. Herein, the concise de novo synthesis of a new double[5]carbohelicene 1 together with its chiroptical properties, isomerization process and lasing application is presented. 1 was synthesized by a simple protocol involving the formation of a 6,6′-bipentacene as the key intermediate. It is worth noting that1 existed as two diastereomers 1-PP/MM and 1-PM, which were successfully isolated and unambiguously confirmed by Xray crystallography. The optical resolution of the racemic 1-PP/MM was successfully achieved by chiral-phase highperformance liquid chromatography（HPLC）, and 1-PP and 1-MM were characterized by circular dichroism. Interestingly, it was found that 1-PP/MM could be completely isomerized to 1-PM upon heating, and the detailed thermodynamics and kinetics of the isomerization process were systematically investigated. 1-PM exhibited deep-red luminescence with emission maximum at 723 nm and fluorescence quantum yield as high as 32.95%. Consequently, we can showcase the lasing application of 1-PM by doping with epoxy resin to assemble a bottle microlaser spontaneously, which the lasing wavelength is 796.6 nm at a threshold of 0.8 m J cm-2. We believe that our studies, including the facile synthesis methodology, detailed isomerization studies, and lasing application, will shed some light on the design and synthesis of novel carbohelical systems with more functions.

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云多租数据库资源规划调度技术综述

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软件学报 2025年第1期36卷 446-468页

作者：刘海龙王硕侯舒峰徐海洋李战怀西北工业大学计算机学院大数据存储与管理工业和信息化部重点实验室(西北工业大学)

云多租数据库具有按需付费、按需扩展、免部署、高可用、自带运维能力、资源共享等诸多优势,可以大大降低用户使用数据库服务的成本.现在越来越多的企业和个人开始在数据库即服务(DaaS)平台托管他们的数据库服务. DaaS平台需要按照用户... 详细信息

云多租数据库具有按需付费、按需扩展、免部署、高可用、自带运维能力、资源共享等诸多优势,可以大大降低用户使用数据库服务的成本.现在越来越多的企业和个人开始在数据库即服务(DaaS)平台托管他们的数据库服务. DaaS平台需要按照用户服务水平协议(SLA)为诸多租户提供服务,同时也需要保障平台收益.但是,由于租户及其负载具有动态性、异构性和竞争性等特点,如何在遵循SLA的同时根据负载自适应规划调度资源同时兼顾平台收益对于DaaS平台来说是一件极具挑战性的工作.针对云多租数据库中比较常见的类型,如关系型数据库,详细分析了当前云多租数据库资源规划调度技术所面临的挑战,提炼了关键科学问题,给出了技术框架,然后从资源规划调度技术、资源预估技术、资源弹性伸缩技术以及数据库资源规划调度工具等4个方面对现有研究工作进行了总结和分析,并且展望了未来的研究方向.

关键词：多租户云数据库资源规划调度资源预估资源弹性伸缩关系数据库云原生多模数据库

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Charmed baryons circa 2015

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Frontiers of physics 2015年第6期10卷 23-49页

作者： hai-yang Cheng Institute of Physics Academia Sinica Taipei

This is essentially an update of Ref. [1] [H. Y. Cheng, Int. J. Mod. Phys. A 24 （Suppl. 1）, 593 （2009）], a review of charmed baryon physics around 2007. Topics covered in this review include the spectroscopy, stro... 详细信息

关键词： charmed baryons spectroscopy decays of baryons chiral Lagrangian

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The Change of Orientation Relationships Between Austenite and α'-Martensite During Deformation in High Manganese TRIP Steel

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Acta Metallurgica Sinica(English Letters) 2015年第3期28卷 289-294页

作者： hai-Yan yang Jing Li Ping yang School of Materials Science and Engineering University of Science and Technology Beijing

In situ observation of electron backscattering diffraction technique was used to evaluate the orientation relationships between austenite and α′-martensite（α′-M） for high manganese transformation-induced plasticity *** was noted that different from the thermal martensite,which well obeyed K-S relationship with austenite,the orientation relationship between deformation-induced α′-M with austenite changed during deformation,namely K-S and N-W relations *** clear differences existed between α′-M variants with two kinds of relationships in terms of martensitic orientation,shape and the misorientation between α′-M *** this phenomenon happened in almost all austenitic grains with different orientations investigated in this *** atom displacement mechanism through conjugate complex slips of partial dislocations in the distorted fcc lattice was applied in this article to interpret the coexistence of K-S and N-W relationships.

关键词： In situ observation Orientation relationship Electron backscattered diffraction technique(EBSD) Martensitic transformation High manganese TRIP steel

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Asymptotic Tail Probability of Randomly Weighted Sums of Dependent Random Variables with Dominated Variation

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Acta Mathematicae Applicatae Sinica 2011年第2期27卷 277-280页

作者： hai-zhong yang School of Statistics Xi'an University of Finance and Economics Xi'an 710100 China

This paper investigates the asymptotic behavior of tail probability of randomly weighted sums of dependent and real-valued random variables with dominated variation, where the weights form another sequence of nonnegat... 详细信息

关键词： randomly weighted sums tail probability dominated variation

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Metal Ions Extraction with Glucose Derivatives as Chelating Reagents in Supercritical Carbon Dioxide

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Chinese Chemical Letters 2006年第11期17卷 1489-1492页

作者： Guo Chen yang hai Jian yang Key Laboratory of Analytical Chemistry of the State Ethnic Affairs Commission College of Chemistry and Materials Science South-Central University for Nationalities Wuhan 430074 Department of Chemistry University of Shanxl Datong Datong 037000

A series of glucose derivatives have been used as chelating reagents to extract metal ions in supercritical carbon dioxide. With perfluoro-l-octanesulfonic acid tetraethylammonium salt as additive, glucose derivatives... 详细信息

关键词： Supercritical carbon dioxide metal ions extraction glucose derivatives selectivity.

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Yemazhui(Herba Eupatorii Lindleyani)ameliorates lipopolysaccharide-induced acute lung injury via modulation of the toll-like receptor 4/nuclear factor kappa-B/nod-like receptor family pyrin domain-containing 3 protein signaling pathway and intestinal flor

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Journal of Traditional Chinese Medicine 2024年第2期44卷 303-314页

作者： REN Li hai yang yang Xue LUO Xianqin Chongqing Key Laboratory of Traditional Chinese Medicine for Prevention and Cure of Metabolic Diseases College of Traditional Chinese MedicineChongqing Medical UniversityChongqing 400016China College of Basic Medicine Chongqing Medical UniversityChongqing 400016China

OBJECTIVE:To investigate the impact of Yemazhui(Herba Eupatorii Lindleyani,HEL)against lipopolysaccharide(LPS)-induced acute lung injury(ALI)and explore its underlying mechanism in ***:The chemical constituents of HEL were analyzed by ultra-high performance liquid chromatographyquadrupole time-of-flight mass spectrometry ***,HEL was found to suppress LPS-induced ALI in ***-week-old male Sprague-Dawley rats were randomly divided into 6 groups:control,LPS,Dexamethasone(Dex),HEL low dose 6 g/kg(HEL-L),HEL medium dose 18 g/kg(HEL-M)and HEL high dose 54 g/kg(HEL-H)*** model rats were intratracheally injected with 3 mg/kg LPS to establish an ALI *** counts,lung wet/dry weight ratio,as well as myeloperoxidase(MPO)activity were determined followed by the detection with hematoxylin and eosin staining,enzyme linked immunosorbent assay,quantitative real time polymerase chain reaction,western blotting,immunohistochemistry,and ***,to explore the effect of HEL on ALI-mediated intestinal flora,we performed 16s rRNA sequencing analysis of intestinal ***:HEL attenuated LPS-induced inflammation in lung tissue and intestinal flora *** study indicated that HEL suppressed the lung coefficient and wet/dry weight ratio of LPS-induced ALI in rats,inhibited leukocytes exudation and MPO activity,and improved the pathological injury of lung *** addition,HEL reduced the expression of tumor necrosis factoralpha,interleukin-1beta(IL-1β)and interleukin-6(IL-6)in bronchoalveolar lavage fluid and serum,and inhibited nuclear displacement of nuclear factor kappa-B p65(NF-κBp65).And 18 g/kg HEL also reduced the expression levels of toll-like receptor 4(TLR4),myeloid differentiation factor 88,NF-κBp65,phosphorylated inhibitor kappa B alpha(phospho-IκBα),nod-like receptor family pyrin domain-containing 3 protein(NLRP3),IL-1β,and interleukin-18(IL-18)in lung tissue,and regulated intestinal flora disturban

关键词： Yemazhui(Herba Eupatorii Lindleyani) acute lung injury anti-inflammation toll-like receptor 4 nuclear factor kappa-B nod-like receptor family pyrin domain-containing 3 protein signal transduction gastrointestinal microbiome

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Long-term optical color behavior of a sample of blazars

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Research in Astronomy and Astrophysics 2018年第12期18卷 67-74页

作者： Xiao-Pan Li Yu-Hui Luo hai-Tao yang hai-Yan yang Cheng yang Yan Cai College of Physics and Information Engineering Zhaotong University College of Photoelectron and Communication Engineering Yunnan Open University

We report on the optical color variability of a sample of 24 blazars, consisting of nine flat spectrum radio quasars(FSRQs) and 15 BL Lacertae objects(BL Lacs), on timescales of years using simultaneous V-and R-band observations observed by the Kanata telescope at Higashi-Hiroshima *** correlations between color indices V-R and magnitudes reveal that 11 BL Lacs and one FSRQ exhibited significant(i.e., r > 0.2 and P < 0.01) bluer-when-brighter(BWB) trend and two FSRQs followed the redder-when-brighter(RWB) tend, indicating a possibility that the BWB chromatic trend is dominant for BL Lacs and the RWB trend is especially found in FSRQs, which has been presented occasionally in different samples of *** superpositions of the red emission component from the Doppler-boosted relativistic jet and the blue component arising from the accretion disk might be a possible interpretation for the long-term color behaviors.

关键词： galaxies:active BL Lacertae objects:general quasars:general methods:statistical

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A General Bayesian Model for Speaker Verification

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Chinese Journal of Electronics 2016年第6期25卷 1045-1051页

作者： XU Yunfei yang hai yang Lin ZHOU Ruohua YAN Yonghong Key Laboratory of Speech Acoustics and Content Understanding Institute of AcousticsChinese Academy of Sciences

This paper presents a general Bayesian model for speaker verification tasks. It is a generative probability model. Due to its simple analytical property, a computationally efficient expectation-maximization algorithm can be derived to obtain the model parameters. A closedform solution, which allows the scalable size of enrollment set, is given in a full Bayesian way for making speaker verification decisions. Factor analysis technique is employed to model the speaker-specific components, then the redundant information in this model will be dropped. Experimental results are evaluated by both equal error rate and minimum detection cost function. The proposed approach shows promising results on the National institute of standards and technology(NIST) Speaker recognition evaluation(SRE) 2010 extended and 2012 core tasks. Significant improvement is obtained when comparing with Gaussian probabilistic linear discriminant analysis, especially under phone-call conditions and mismatched train-test channel conditions. Contrast experimental results with other popular generative probability models are also presented in this paper.

关键词： Bayesian model Speaker verification I-Vector

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On a Nonparametric Estimator for the Finite Time Survival Probability with Zero Initial Surplus

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Acta Mathematicae Applicatae Sinica 2016年第3期32卷 739-754页

作者： Zhi-min ZHANG hai-liang yang Hu yang College of Mathematics and Statistics Chongqing University Department of Statistics and Actuarial Science The University of Hong Kong

In this paper, we consider the estimation of the finite time survival probability in the classical risk model when the initial surplus is zero. We construct a nonparametric estimator by Fourier inversion and kernel density estimation method. Under some mild assumptions imposed on the kernel, bandwidth and claim size density, we derive the order of the bias and variance, and show that the estimator has asymptotic normality property. Some simulation studies show that the estimator performs quite well in the finite sample setting.

关键词： finite time survival probability fourier transform kernel bias variance asymptotic normality

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