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Photocatalytic vinyl radical-mediated multicomponent 1,4-/1,8-carboimination across alkynes and olefins/(hetero)arenes

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Science China Chemistry 2024年第2期67卷 558-567页

作者： Shan-Shan li Yu-Shi Jiang Xue-ling Luo Xuming Ran yuqiang li Dong Wu Cheng-Xue Pan Peng-Ju Xia School of Chemistry and Pharmaceutical Sciences Guangxi Normal UniversityGuilin541004China Shanghai Artificial Intelligence Laboratory Shanghai200433China The Institute for Advanced Studies Wuhan UniversityWuhan430064China

We developed a highly selective and efficient multicomponent transformation by utilizing alkynes and olefins/(hetero)arenes through photoinduced energy-transfer catalysis.The reaction involves the formation of three distinct chemical bonds,namely C(sp~3)–C(sp~2),C(sp~2)–C(sp~3),and C(sp~3)–N,in a single coordinated manner.The strategy used a vinyl radical-mediated radical relay approach under mild conditions,exhibiting a broad substrate scope(>70 examples),excellent functional-group tolerance,and remarkable regio-and anti-stereoselectivity.Through the utilization of a combination of experimental techniques and density functional theory(DFT),we delved deeper into the mechanistic intricacies of this distinctive system.Results revealed that the selective radical addition to electron-deficient alkynes,rather than olefins,was governed by the inherent reactivity of alkyl radicals.This discovery presented a highly effective approach for the synthesis of stereodefined multisubstituted alkenes.

关键词： alkyne-olefin coupling DFT studies regio-and anti-stereoselectivity multisubstituted alkenes

Outage Probability Analysis for D2D-Enabled Heterogeneous Cellular Networks with Exclusion Zone:A Stochastic Geometry Approach

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工程与科学中的计算机建模(英文) 2024年第1期138卷 639-661页

作者： Yulei Wang li Feng Shumin Yao Hong liang Haoxu Shi yuqiang Chen School of Computer Science and Engineering Macao University of Science and TechnologyTaipaMacaoChina Department of Broadband Communication Peng Cheng LaboratoryShenzhenChina School of Artificial Intelligence Dongguan PolytechnicDongguanChina

Interference management is one of the most important issues in the device-to-device(D2D)-enabled heterogeneous cellular networks(HetCNets)due to the coexistence of massive cellular and D2D devices in which D2D devices reuse the cellular spectrum.To alleviate the interference,an efficient interference management way is to set exclusion zones around the cellular receivers.In this paper,we adopt a stochastic geometry approach to analyze the outage probabilities of cellular and D2D users in the D2D-enabled HetCNets.The main difficulties contain three aspects:1)how to model the location randomness of base stations,cellular and D2D users in practical networks;2)how to capture the randomness and interrelation of cellular and D2D transmissions due to the existence of random exclusion zones;3)how to characterize the different types of interference and their impacts on the outage probabilities of cellular and D2D users.We then run extensive Monte-Carlo simulations which manifest that our theoretical model is very accurate.

关键词： Device-to-device(D2D)-enabled heterogeneous cellular networks(HetCNets) exclusion zone stochastic geometry(SG) Matérn hard-core process(MHCP)

Microsatellite marker development and population genetic analysis revealed high connectivity between populations of a periwinkle littoraria sinensis(Philippi,1847)

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Journal of Oceanology and limnology 2022年第3期40卷 1097-1109页

作者： Mengyu li yuqiang li Tengfei XING Yulong li Jinxian liU CAS Key Laboratory of Marine Ecology and Environmental Sciences Institute of OceanologyChinese Academy of SciencesQingdao 266071China Laboratory for Marine Ecology and Environmental Science Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China Center for Ocean Mega-Science Chinese Academy of SciencesQingdao 266071China University of Chinese Academy of Sciences Beijing 100049China

Periwinkle littoraria sinensis is a widely distributed gastropod in rocky intertidal zone of the northwestern Pacifi c.To examine genetic diversity and genetic connectivity among coastal populations of L.sinensis in China,1636 pairs of primers were successfully designed using whole-genome shotgun sequencing,de novo assembly,and a bioinformatics pipeline QDD.Twelve highly variable polymorphic markers were selected to genotype 351 individuals from 15 populations.Data of nine microsatellite loci were retained for population genetic analysis,and weak genetic differentiation among populations were detected,suggesting high gene flow among populations.The long planktonic larval duration of L.sinensis might have played an important role in the high gene flow among populations.A tendency of genetic differentiation between north and south populations of L.sinensis was detected,which might be resulted from isolation due to lowered sea level in the last glacial maximum.Furthermore,the newly founded populations along the coast of Jiangsu Province were closely related to populations to the south of the Changjiang(Yangtze)River estuary,suggesting that the main source of the newly founded populations is from natural rocky populations south of the estuary.

关键词： population genetics littoraria sinensis gastropod simple-sequence repeats

The particular species determining spatial heterogeneity in shady and terrace on the Qinghai-Tibetan Plateau,China

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Research in Cold and Arid Regions 2023年第1期15卷 39-47页

作者： XiaoMing Mou YingWen Yu Min Zhao yuqiang li Masae Shiyomi Northwest Institute of Eco-Environment and Resources Naiman Desertification Research StationChinese Academy of SciencesLanzhouGansu 730000China State Key Laboratory of Herbage Improvement and Grassland Agro-ecosystems College of Pastoral Agriculture Science and TechnologyLanzhou UniversityLanzhouGansu 730020China Ibaraki University Professor EmeritusBunkyo 2-1Mito 310-8512Japan

Spatial patterns of plant species and patchy community are important properties in grasslands.However,research regarding spatial patterns of formed patches with various species has not fully advanced until now.Our purpose is to clarify differences in spatial pattern formed by species and community constructed under shady and terrace habitats.The three common Kobresia-Carex patches(Size 1,0.6–0.9 m^(2);Size 2,3.0–3.8 m^(2) and Size 3,6.5–8.8 m^(2))were selected in shady and terrace on the Qinghai-Tibetan Plateau,and corresponding quadrats of 1m1m,2m2m and 3m3m were placed for S1,S2 and S3 patches,respectively.The surveyed quadrats were divided into 20cm20cm large cells(L-cells),and further divided into four 10cm10cm small cells(S-cells).We used the binary occurrence system(presence/absence data)to record occurrences of all species in S-cells.The analysis shows that the power law model was well able to determine the spatial distribution pattern of species or patchy community in shady and terrace.All species and patches show aggregated distribution in shady and terrace habitats.In the shady habitat,the relative spatial heterogeneity(ε)of individual plant species was lowest at presence frequency(P)of 0.1–0.3,whereas in the terrace habitatεwas lowest at P<0.1,andεincreased monotonically with increasing P.For most dominant species,P andεvalues were higher in terrace than those in shady.We concluded that the dominant species largely determine spatial heterogeneity of the Kobresia-Carex patches,while companion and rare species have weak influence on the community-level heterogeneity in shady and terrace habitats.

关键词： Dominant species Power law Qinghai-Tibetan Plateau Spatial heterogeneity Vegetation patches

Countermeasure against blinding attack for single-photon detectors in quantum key distribution

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Journal of Semiconductors 2024年第4期45卷 76-81页

作者： lianjun Jiang Dongdong li yuqiang Fang Meisheng Zhao Ming liu Zhilin Xie Yukang Zhao Yanlin Tang Wei Jiang Houlin Fang Rui Ma Lei Cheng Weifeng Yang Songtao Han Shibiao Tang QuantumCTek Co. Ltd.Hefei 230088China Shandong Institute of Quantum Science and Technology Co. Ltd.Jinan 250101China QuantumCTek(Beijing)Co. Ltd.Beijing 100193China School of Cyber Science and Technology University of Science and Technology of ChinaHefei 230027China Anhui Armed Police Force Hefei 230026China School of Electrical Engineering and Automation Anhui UniversityHefei 230601China

Quantum key distribution(QKD),rooted in quantum mechanics,offers information-theoretic security.However,practi-cal systems open security threats due to imperfections,notably bright-light blinding attacks targeting single-photon detectors.Here,we propose a concise,robust defense strategy for protecting single-photon detectors in QKD systems against blinding attacks.Our strategy uses a dual approach:detecting the bias current of the avalanche photodiode(APD)to defend against con-tinuous-wave blinding attacks,and monitoring the avalanche amplitude to protect against pulsed blinding attacks.By integrat-ing these two branches,the proposed solution effectively identifies and mitigates a wide range of bright light injection attempts,significantly enhancing the resilience of QKD systems against various bright-light blinding attacks.This method forti-fies the safeguards of quantum communications and offers a crucial contribution to the field of quantum information security.

关键词： quantum key distribution single photon detector blinding attack pulsed blinding attack countermeasure quan-tum communication

Simultaneously optimizing exciton diffusion length and nonradiative energy loss in organic solar cells via ternary strategy

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Science China Chemistry 2024年

作者： Huanxiang Jiang Hao Lu Zezhou liang Yonghai li Guangliu Ran Chenyu Han yuqiang liu Hongxiang li Xichang Bao Zhishan Bo College of Textiles and Clothing State Key Laboratory of Bio-fibers and Eco-textiles Qingdao University Key Laboratory for Physical Electronics and Devices of the Ministry of Education & Shaanxi Key Lab of Photonic Technique for InformationSchool of Electronics Science & Engineering Faculty of Electronic and Information Engineering Xi'an Jiaotong University Qingdao Institute of Bioenergy and Bioprocess Technology Chinese Academy of Sciences Laboratory of Solar Energy Shandong Energy Institute Department of Physics and Applied Optics Beijing Area Major Laboratory Center for Advanced Quantum Studies Beijing Normal University College of Polymer Science and Engineering State Key Laboratory of Polymer Materials Engineering Sichuan University

Significant nonradiative energy loss and short exciton diffusion length in organic solar cells (OSCs) are two major obstacles to achieving state-of-the-art efficiencies. It is crucial to conduct a study on the intensive mechanism and improvement strategies for future breakthroughs in the efficiency of OSCs. In this work, nonradiative energy loss and exciton diffusion length are optimized simultaneously by incorporating a guest acceptor (LA15) to construct ternary OSC (D18:L8-BO:LA15). Firstly, LA15 exhibits excellent compatibility with the host acceptor L8-BO, and effectively improves the fluorescence quantum efficiency (FLQY),resulting in suppressed non-radiative energy loss. Moreover, LA15 effectively prolongs the fluorescent lifetime of the acceptor phase from 0.85 to 1.12 ns, leading to larger exciton diffusion length, which is beneficial for reducing geminate recombination.Besides, the addition of LA15 optimizes the crystallinity of the active layer with amplified charge transport capacity. As a result,the optimized D18:L8-BO:LA15 device achieves ultralow nonradiative energy loss of 0.18 eV and improved fill factor (FF) with high efficiency up to 19.13%. These results highlight the crucial roles of regulating FLQYand exciton lifetime in achieving highefficiency OSCs.

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代谢相关脂肪性肝病合并慢性乙型肝炎患者进展期纤维化分析

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中华内科杂志 2024年第1期63卷 53-58页

作者：吴雪李萍宓余强天津市第二人民医院中西医结合肝病二科天津市肝病医学研究所天津300192 华中科技大学协和深圳医院感染科

目的探究代谢相关脂肪性肝病(MAFLD)合并慢性乙型肝炎(CHB)患者肝脏病理特点,以及与进展期纤维化之间的关系。方法病例对照研究。收集2016年6月至2019年9月在天津市第二人民医院进行肝组织活检的CHB患者数据。根据是否合并MAFLD将患者分... 详细信息

目的探究代谢相关脂肪性肝病(MAFLD)合并慢性乙型肝炎(CHB)患者肝脏病理特点,以及与进展期纤维化之间的关系。方法病例对照研究。收集2016年6月至2019年9月在天津市第二人民医院进行肝组织活检的CHB患者数据。根据是否合并MAFLD将患者分为MAFLD-CHB组和CHB组,采用t检验和卡方检验比较两组间病理特点及一般基本特征,采用logistic回归分析进展期纤维化相关因素。结果本研究共纳入272例MAFLD-CHB患者和110例单独CHB患者,两组在吸烟、饮酒、高血压发生率、身体代谢指标(BMI)、丙氨酸转氨酶(ALT)、γ-谷氨酰转肽酶(GGT)、高密度脂蛋白(HDL)、低密度脂蛋白(LDL)、空腹血糖水平(FPG)、血小板计数(PLT)方面差异均有统计学意义(均P<0.05)。MAFLD-CHB组进展期纤维化发生率高于CHB组(P<0.05)。logistic回归分析显示,合并MAFLD(OR=2.204,95%CI 1.018~4.774,P=0.045)、GGT(OR=1.008,95%CI 1.002~1.013,P=0.005)、PLT(OR=0.995,95%CI 0.991~0.999,P=0.019)与进展期纤维化发生相关。在MAFLD-CHB组中,合并2型糖尿病(OR=3.281,95%CI 1.375~7.832,P=0.007)、GGT(OR=1.011,95%CI 1.003~1.018,P=0.005)、PLT(OR=0.993,95%CI 0.988~0.998,P=0.004)与进展期纤维化发生相关。结论MAFLD-CHB患者进展期纤维化发生率高于单独CHB患者。在MAFLD-CHB组中,合并2型糖尿病与进展期肝纤维化发生相关。对于MAFLD-CHB患者,应更加严格控制相关危险因素,尤其对于合并2型糖尿病的患者。

关键词：脂肪肝肝炎乙型慢性纤维化

Highly efficient solution-processed organic photovoltaics enabled by improving packing behavior of organic semiconductors

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Science China Chemistry 2024年第3期67卷 890-897页

作者： Xinyue Cui Hongxiang li Hao Lu yuqiang liu Guangliu Ran Rui liu Huarui Zhang Xueqing Ma Dawei li Yi lin Jifa Yu Wenkai Zhang Lei Cai Yahui liu Pei Cheng Andong Zhang Zaifei Ma Guanghao Lu Zhishan Bo College of Textiles and Clothing State Key Laboratory of Bio-fibers and Eco-textilesQingdao UniversityQingdao 266071China State Key Laboratory of Polymer Materials Engineering College of Polymer Science and EngineeringSichuan UniversityChengdu 610065China Department of Physics and Applied Optics Beijing Area Major Laboratory Center for Advanced Quantum StudiesBeijing Normal UniversityBeijing 100875China Shandong Province Key Laboratory of Medical Physics and Image Processing Technology School of Physics and ElectronicsShandong Normal UniversityJinan 250014China Beijing Key Laboratory of Energy Conversion and Storage Materials College of ChemistryBeijing Normal UniversityBeijing 100875China Center for Advanced Low-Dimension Materials State Key Laboratory for Modification of Chemical Fibers and Polymer MaterialsCollege of Materials Science and EngineeringDonghua UniversityShanghai 201620China Frontier Institute of Science and Technology Xi'an Jiaotong UniversityXi'an 710054China

Solution processability is a unique property of organic semiconductors. The compact and regular π-π stacking between molecules is paramount in the performance of organic optoelectronic devices. However, it is still a challenge to improve their stacking quality without sacrificing the solution-processability from the aspect of materials design. Here, delicately engineered additives are presented to promote the formation of ordered aggregation of conjugated molecules by regulating their nucleation and growth dynamics. Intriguingly, the long-chain BTP-eC9-4F molecules can realize ordered aggregation comparable to short-chain ones without sacrificing processability. The domain size of BTP-eC9-4F aggregation is enlarged from 24.2 to 32.2 nm in blend films.Thereby exciton diffusion and charge transport become faster, contributing to the suppression of recombination losses. As a result, a power conversion efficiency of 19.2% is achieved in D18:BTP-eC9-4F based organic photovoltaics. Our findings demonstrate a facile strategy to improve the packing quality of solution-processed organic semiconductors for high-efficiency photovoltaics and beyond photovoltaics.

关键词： organic semiconductor organic photovoltaic charge transport solution processability

limit theorems of continuous-time random walks with tails

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Frontiers of Mathematics in China 2013年第2期8卷 371-391页

作者： yuqiang li School of Finance and Statistics East China Normal University Shanghai 200241 China

We study the functional limits of continuous-time random walks （CTRWs） with tails under certain conditions. We find that the scaled CTRWs with tails converge weakly to an a-stable Levy process in D（[0, 1]） with M1... 详细信息

关键词： Weak convergence J1-topology M1-topology stable Levy process