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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

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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A Model of Hydrothermal Dolomite Reservoir Facies in Precambrian Dolomite, Central Sichuan Basin, SW China and its Geochemical Characteristics

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Acta Geologica Sinica(English Edition) 2019年第1期93卷 130-145页

作者： GU Yifan ZHOU Lu jiang yuqiang jiang Chan LUO Mingsheng ZHU Xun School of Geosciences & Technology Southwest Petroleum University Exploration Division PetroChina Southwest Oil & Gas Field Company Shunan Division of Petrochina Southwest Oil&Gas Field Company Exploration and Development Institute of Southwest Oil&Gas Field Company PetroChina

Hydrothermal mineral assemblages and related hydrothermally enhanced fracturing are common in the Precambrian Dengying Formation of Central Sichuan Basin. Petrographic and geochemical analyses of core samples show that the hydrothermal dolomite reservoirs of Dengying Formation consist of four main types of pores in the reservoir facies. These include: 1) hydrothermal dissolution vug(or pore), 2) intercrystalline pore, 3) residual inter-breccia vug(or pore), and 4) enlarged dissolved-fracture. There are three different fabrics dolomite in hydrothermal dolomite reservoirs, namely, saddle dolomite, fine-medium dolomite and micritic dolomite. Micritic dolomite is the original lithology of host rock. Saddle dolomite with curved or irregular crystal faces was directly crystallized from hydrothermal fluids(average temperature 192°C). Fine-medium dolomites are the products of recrystallization of micritic dolomite, resulting in abnormal geochemical characteristics, such as slight depletion of δ^(18)O, significant enrichment of Mn-Fe and ^(87)Sr/^(86)Sr, and positive Eu anomaly. A model for the distribution of various hydrothermal dolomite reservoir facies is proposed here, which incorporates three fundamental geological controls: 1) extensional tectonics and tectono-hydrothermal events(i.e., the Xingkai Taphrogenesis of Late Sinian-Early Cambrian, and Emei Taphrogenesis of Late Permian), 2) hydrothermal fluid storage in clastic rocks with large thickness(e.g., Nanhua System of Chengjiang Formation and part of Doushantuo Formation), and 3) confining bed for hydrothermal fluids(such as, the shale in Qiongzhusi Formation). The supply of hydrothermal fluid is critical. Large basement-rooted faults and associated grid-like fracture system may function as the channels for upward migration of hydrothermal fluid flow. The intersection of the above-mentioned faults(including the conversion fault), especially transtensional sags above negative flower structures on wrench faults can serve as a key target for future hydrocarbon expl

关键词： hydrothermal dolomite reservoir facies geochemical characteristics Precambrian Dengying Formation central Sichuan Basin

The Major Controlling Factors and Different Oolitic Shoal Reservoir Characteristics of the Triassic Feixianguan Formation,Eastern Longgang Area,NE Sichuan Basin,SW China

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Acta Geologica Sinica(English Edition) 2021年第3期95卷 895-908页

作者： GU Yifan jiang yuqiang LEI Xiaohua CHEN Zhiyong ZHOU Lu FU Yonghong jiang Zengzheng School of Geoscience and Technology Southwest Petroleum UniversityChengdu 610500China Department of Geology University of ReginaReginaSaskatchewanSK S4S 0A2Canada Northeastern Sichuan Oil and Gas District PetroChina Southwest Oil and Gas Field CompanyDazhouSichuan 635000China Chongqing Gas Field PetroChina Southwest Oil and Gas Field CompanyChongqing 400021China Sichuan Geotech Science and Technology Ltd. Chengdu 610041China

Based on comprehensive analyses of occurrence,petrological observation,pore structure and geochemistry,the different reservoir characteristics and reservoir evolutionary pathways between different oolitic shoal reservoir types of the Feixianguan Formation on the west side of the Kaijiang-Liangping Trough have been studied.There exist three stages of high-energy slope break belts in the Feixianguan period,the corresponding three stages of oolitic shoals gradually migrating in the direction of the trough.Three types of oolitic shoal reservoirs,namely,residual-oolitic dolomite,mold-oolitic dolomite and sparry oolitic limestone,were formed during sedimentary-diagenetic evolution,the pore types being intergranular dissolved pore,mold pore(or intragranular dissolved pore)and residual intergranular pore,respectively.The petrology,physical properties and pore structure of the different types of oolitic shoal reservoirs are quite different.Residual-oolitic dolomite reservoirs have the best quality,while sparry oolitic limestone reservoirs have the poorest.Combined with analyses of trace elements,rare earth elements and carbon-oxygen isotopes,it is suggested that the formation of residual-oolitic dolomite reservoirs is jointly controlled by penesaline seawater seepage-reflux dolomitization and hydrothermal dolomitization.Mold-pore oolitic dolomite reservoirs are controlled by penesaline seawater seepage-reflux dolomitization and meteoric water solution.The burial dissolution of organic acid not only further improves the reservoir qualities of previously formed oolitic dolomite reservoirs,but also preserves residual intergranular pores in the sparry oolitic limestone reservoirs.

关键词： oolitic shoal reservoir evolution geochemical characteristics Triassic System Feixianguan Formation Sichuan Basin

一种大斯托克斯位移的红光发射荧光探针选择性检测次氯酸

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无机化学学报 2024年第6期40卷 1095-1104页

作者：白佳坤徐婷张璐彭江李宇强贾俊辉山西师范大学化学与材料科学学院教育部磁性分子与磁信息材料重点实验室太原030032 中北大学化学与化工学院太原030051

设计、合成了一种基于巴比妥酸衍生物的具有D-π-A结构的光学探针3。该探针能够作为一种高度灵敏和选择性的次氯酸指示剂,快速实现对次氯酸的比色和荧光信号(开-关)的双响应(约15 s)。推测的响应机制是ClO-与C=C之间发生了亲电加成和氧... 详细信息

设计、合成了一种基于巴比妥酸衍生物的具有D-π-A结构的光学探针3。该探针能够作为一种高度灵敏和选择性的次氯酸指示剂,快速实现对次氯酸的比色和荧光信号(开-关)的双响应(约15 s)。推测的响应机制是ClO-与C=C之间发生了亲电加成和氧化裂解反应,导致探针的D-π-A结构遭到破坏,从而阻断了其分子内电荷转移(intramolecular charge transfer,ICT)进程。探针只需一步即可合成,同时具有红光发射(628 nm)和较大的斯托克斯位移(158 nm),检测限(limit of detection,LOD)低至14 nmol·L^(-1)。此外,探针还表现出低细胞毒性,并成功应用于活细胞成像。

关键词：大斯托克斯位移次氯酸检测比色荧光双响应红光发射细胞成像

CD4^(+)T淋巴细胞及身体成分与重庆市老年HIV感染者生理衰弱的关联分析

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中华预防医学杂志 2024年第2期58卷 235-240页

作者：陈晨徐杰江震吴国辉张裕强赵燕吴尊友中国疾病预防控制中心性病艾滋病预防控制中心北京102206 重庆市疾病预防控制中心重庆400042 重庆市江津区疾病预防控制中心性病艾滋病预防控制科重庆402260 中国疾病预防控制中心性病艾滋病预防控制中心治疗与关怀室北京102206

目的探索CD4^(+)T淋巴细胞(CD4细胞)计数水平与老年HIV感染者生理衰弱患病的关联关系及体成分指标对二者的修饰作用。方法2022年5—10月于重庆市江津区疾病预防控制中心辖区内7家抗病毒治疗点招募485例接受抗反转录病毒治疗(ART)的老年... 详细信息

目的探索CD4^(+)T淋巴细胞(CD4细胞)计数水平与老年HIV感染者生理衰弱患病的关联关系及体成分指标对二者的修饰作用。方法2022年5—10月于重庆市江津区疾病预防控制中心辖区内7家抗病毒治疗点招募485例接受抗反转录病毒治疗(ART)的老年HIV感染者。采用自制问卷通过面对面调查收集对象基本特征(年龄和性别)、生活习惯(吸烟和饮酒情况)和疾病史情况(包括代谢性疾病、心脑血管疾病、呼吸系统疾病和恶性肿瘤)等资料。采用Fried量表评估研究对象的生理衰弱情况。进行体质(步速、握力、身高和体重)和体成分(骨骼肌量、体脂肪量和基础代谢率)测量。由中国艾滋病综合防治数据信息管理系统获取对象抗反转录病毒治疗资料。计算老年感染者生理衰弱现患率,采用多因素logistic回归探索不同CD4水平对老年HIV感染者生理衰弱的影响,并对体成分指标进行亚组分析探索是否存在交互作用。结果485例对象年龄为(72±5)岁,其中>70岁者占48.2%(234例),男性占70.9%(344例),且已全部启动抗病毒治疗。老年HIV感染者生理衰弱率为7.4%(36/485)。多因素logistic回归模型分析显示:调整年龄、性别、吸烟、饮酒、体成分指标、ART时长、病毒载量和合并症数量等因素后,CD4细胞水平增加与老年HIV感染者生理衰弱患病风险下降相关;CD4细胞每增加5.0×10^(7)个/L,老年感染者生理衰弱患病风险下降12%[OR(95%CI):0.88(0.76~1.01)];与CD4细胞低水平组相比,CD4细胞正常水平组生理衰弱风险下降69%[OR(95%CI):0.31(0.10~0.92)]。体成分指标亚组分析显示:CD4细胞水平与生理衰弱的关联在高骨骼肌量和高基础代谢率感染者中更强(P交互值<0.05)。结论重庆市老年HIV感染者生理衰弱率相对较低;CD4细胞水平、骨骼肌量和基础代谢率与生理衰弱有关联。

关键词： HIV 老年人 CD4^(+)T淋巴细胞身体成分生理衰弱

Learning power Gaussian modeling loss for dense rotated object detection in remote sensing images

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Chinese Journal of Aeronautics 2023年第10期36卷 353-365页

作者： Yang LI Haining WANG yuqiang FANG Shengjin WANG Zhi LI Bitao jiang Department of Space Information Space Engineering UniversityBeijing 101416China Beijing Institute of Remote Sensing Information Beijing 100192China Department of Electronic Engineering Tsinghua UniversityBeijing 100084China

Object detection in Remote Sensing(RS)has achieved tremendous advances in recent years,but it remains challenging for rotated object detection due to cluttered backgrounds,dense object arrangements and the wide range of size variations among objects.To tackle this problem,Dense Context Feature Pyramid Network(DCFPN)and a powerα-Gaussian loss are designed for rotated object detection in this paper.The proposed DCFPN can extract multi-scale information densely and accurately by leveraging a dense multi-path dilation layer to cover all sizes of objects in remote sensing scenarios.For more accurate detection while avoiding bottlenecks such as boundary discontinuity in rotated bounding box regression,a-Gaussian loss,a unified power generalization of existing Gaussian modeling losses is proposed.Furthermore,the properties ofα-Gaussian loss are analyzed comprehensively for a wider range of applications.Experimental results on four datasets(UCAS-AOD,HRSC2016,DIOR-R,and DOTA)show the effectiveness of the proposed method using different detectors,and are superior to the existing methods in both feature extraction and bounding box regression。

关键词： Convolutional neural networks Distribution metric Losses Remote sensing Rotated object detection

夹层型页岩油突破及其油气地质意义——以四川盆地中部G119H井为例

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天然气工业 2024年第3期44卷 53-63页

作者：郭贵安唐青松蒋裕强朱讯方锐周亚东洪海涛张连进张新宇中国石油西南油气田公司西南石油大学地球科学与技术学院中国石油非常规油气重点实验室储层评价实验室中国石油西南油气田公司勘探开发研究院中国石油西南油气田公司开发事业部

近期,中国石油西南油气田公司在四川盆地中部(以下简称川中)公山庙西地区部署实施的侏罗系凉高山组夹层型页岩油重点评价井——G119H井,测试获产油20 t/d、产气0.6×10^(4) m^(3)/d,取得了该盆地湖相夹层型页岩油的新突破。为了进一步... 详细信息

近期,中国石油西南油气田公司在四川盆地中部(以下简称川中)公山庙西地区部署实施的侏罗系凉高山组夹层型页岩油重点评价井——G119H井,测试获产油20 t/d、产气0.6×10^(4) m^(3)/d,取得了该盆地湖相夹层型页岩油的新突破。为了进一步明确四川盆地凉高山组湖相页岩油的资源潜力及勘探前景,基于G119H井所在区域的地质、地震资料,开展了凉高山组沉积地质背景、河道刻画、优质储层特征、富集模式等研究。研究结果表明:(1)凉高山组在多期湖盆迁移背景下,纵向发育多期叠置湖相页岩、三角洲前缘砂体;(2)公山庙西地区凉二段底部发育浅水三角洲前缘砂体,砂体由西南向北东推进入湖;(3)凉二段分流河道为最有利微相,岩性主要为细—中粒岩屑砂岩,平均孔隙度达6.3%,孔喉结构为小孔—微喉连通模式,可动油占比较高;(4)凉高山组夹层型页岩油分布广,具备烃源岩厚度大(超过10 m)、储层物性好、源储组合相邻匹配等有利条件;(5)该盆地内凉高山组夹层型页岩油有利地区面积约1.38×10^(4) km^(2),利用四川盆地现有三维地震资料刻画凉二段分流河道分布面积为2 336 km^(2),估算石油资源量约15×10^(8) t。结论认为,G119H井的突破揭示了川中地区凉二段夹层型页岩油具有规模开发潜力,进一步展现了盆地侏罗系页岩油良好的资源基础,明确了川中地区凉二段夹层型页岩油是“十四五”及中长期增储上产重点层段。

关键词：四川盆地夹层型页岩油侏罗系凉高山组公山庙勘探突破

Spiral fractal patterns via hierarchical assembly

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Nano Research 2022年第2期15卷 1079-1086页

作者： Li Zhang Ming Deng Yu Duan Xin Wen Yuqian jiang Hejin jiang yuqiang Ma Minghua Liu Beijing National Laboratory for Molecular Science(BNLMS) CAS Key Laboratory of ColloidInterface and Chemical Thermodynamics Institute of ChemistryChinese Academy of SciencesBeijing 100190China National Laboratory of Solid State Microstructures and Department of Physics Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210093China National Center for Nanoscience and Technology Beijing 100190China

Chirality is ubiquitous in nature and manifested at various scale from subatom to galaxy.Fractal geometry is also very popular and active in the world.However,there are few reports on the concept of combining fractal patterns and chiral structures in self-assembled systems.It was found that tree-shaped fractal patterns could be self-assembled from the N-[(9H-fluoren-9-ylmethoxy)carbonyl]protected glutamic acid(Fmoc-Glu)and zinc-porphyrin(ZnTPyP).The fractal pattern was composed of nanorod aggregate arranged in a spiral fractal way,in which the nanorods were stacked one-by-one in a single direction.The patterns started with the formation of initial nucleon and growing,during which the diffusion limited aggregation(DLA)mechanism led to the fractal patterns.Interestingly,the spiral packing and their branches were closely related to the absolute configuration of Fmoc-Glu that anticlockwise and clockwise arrangement for L-Fmoc-Glu/ZnTPyP and D-Fmoc-Glu/ZnTPyP,respectively.Our work provides a new finding on the spiral fractal pattern via hierarchical self-assembly.

关键词： self-assembly chiral spiral fractal porphyrin