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1,1’-Binaphthol annulated perylene diimides: Aggregation-induced emission enhancement and chirality inversion

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Chinese Chemical Letters 2022年第5期33卷 2473-2476页

作者： Yang Zhang juejun wang Hongming Chen Meijin Lin Key Laboratory of Molecule Synthesis and Function Discovery College of ChemistryFuzhou UniversityFuzhou 350116China College of Materials Science and Engineering Fuzhou UniversityFuzhou 350116China

Aggregation-induced emission enhancement and aggregation-induced chirality inversion are two individ-ual phenomena for the enantiomerically pure organic dyes in the *** we reported for the first time that these two interesting phenomena could be observed simultaneously in the aggregated states of enantiomerically pure S/R-1,1?-binaphthol annulated perylene diimides,in which two perylene diimides moieties were bridged by S/R-1,1?-binaphthol(BINOL)at the bay *** to the rotat-able C2 axes between two naphthol annulated perylene diimides moieties,both of them display intrinsic behaviors of aggregation-induced emission *** the same time,due to the steric hindrances in the imide and methoxy positions,the neighboring twoπ-systems of these two unique polycyclic aro-matic imides in poor solvents are preferable to adopt a cross-stacking mode and thus form helical X-aggregates of opposite chirality(M/P)with chirality inversion characteristics in their circular dichroism and circularly polarized luminescence spectroscopic studies.

关键词： Perylene diimides 1,1’-Binaphthol Aggregation-induced emission enhancement Chirality inversion

Detecting the single chiral molecule during the reaction

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中国科学:材料科学(英文版) 2023年第8期66卷 3377-3378页

作者： juejun wang Zepeng Zhang Shurui Ji Yanxi Zhang Wenjing Hong College of Chemistry and Chemical Engineering Xiamen UniversityXiamen 361005China The Institute of Flexible Electronics(IFE Future Technologies)Xiamen UniversityXiamen 361005China

Detecting an individual molecule during the chemistry dynamics is essential for capturing accurate information about the chemical process in the time domain,which could be achieved by precisely forming single-molecule junctions between two electrodes and reading out the variation in electrical signals[1–3],but has yet to penetrate the stereochemistry *** is a crucial pursuit of chirality chemistry to develop effective asymmetric synthesis methodologies and reveal the physicochemical mechanisms[4,5].And the key obstacle lies in achieving in situ detection of chiral intermediates in reactions[6].Chirality is a fundamental molecular property arising from the structure asymmetry,with two mirror-image forms known as *** to similar signals of enantiomeric isomers,it is a great challenge to distinguish chiral species and the process of their configurational transformation in single-molecule *** then comes up with a question—how to detect chirality changes in stereochemistry.

关键词： chiral isomers mirror

The impact of vertical π-extension on redox mechanisms of aromatic diimide dyes

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Chinese Chemical Letters 2019年第12期30卷 2254-2258页

作者： Lei Li juejun wang Mengting Chen Yong Chen wangchuan Xiao Dongyang Chen Meijin Lin College of Chemistry Fuzhou UniversityFuzhou 350116China College of Materials Science and Engineering Fuzhou UniversityFuzhou 350116China School of Resources and Chemical Engineering Sanming Institute of Fluorochemical IndustrySanming UniversitySanming 365004China

Aromatic diimide dyes are an attractive class of redox-active organic molecules for lithium-ion batteries,whose battery performances(stabilities,conductivities and cyclicities) are strongly dependent on the sizes of their π-***,due to the different Clar’s structures possessed,three vertically7 r-extended aromatic diimides,namely,naphthalene diimide(two one-electron reductions),perylene diimide and terrylene diimide(two one-electron reductions),exhibit different electronic redox mechanisms when served as cathode materials in organic lithium-ion ***,we have studied carefully the different electrochemical characteristics of the three aromatic diimides through experimental and theoretical *** battery present different shape of charge/discharge curves resulting from stability of their reduction state during charge/discharge *** diimide shows better cycle and rate capacities than those of naphthalene diimide and perylene diimide,which could be attributed to the more energies released during terrylene diimide combining with lithium ions than those of other two diimides.

关键词： Aromatic diimides Lithium-ion batteries π-Systems Redox mechanisms Clar's structures

All-optical computing based on convolutional neural networks

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Opto-Electronic Advances 2021年第11期4卷 46-54页

作者： Kun Liao Ye Chen Zhongcheng Yu Xiaoyong Hu Xingyuan wang Cuicui Lu Hongtao Lin Qingyang Du juejun Hu Qihuang Gong State Key Laboratory for Mesoscopic Physics&Department of Physics Collaborative Innovation Center of Quantum MatterBeijing Academy of Quantum Information SciencesNano-optoelectronics Frontier Center of Ministry of EducationPeking UniversityBeijing 100871China Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuan 030006China College of Mathematics and Physics Beijing University of Chemical TechnologyBeijing 100029China Beijing Key Laboratory of Nanophotonics and Ultrafine Optoelectronic Systems School of PhysicsBeijing Institute of TechnologyBeijing 100081China College of Information Science&Electronic Engineering Zhejiang UniversityHangzhou 310027China Department of Materials Science and Engineering Massachusetts Institute of TechnologyCambridgeMA 02139USA

The rapid development of information technology has fueled an ever-increasing demand for ultrafast and ultralow-en-ergy-consumption *** computing instruments are pre-dominantly electronic processors,which use elec-trons as information carriers and possess von Neumann architecture featured by physical separation of storage and *** scaling of computing speed is limited not only by data transfer between memory and processing units,but also by RC delay associated with integrated ***,excessive heating due to Ohmic losses is becoming a severe bottleneck for both speed and power consumption *** photons as information carriers is a promising *** to the weak third-order optical nonlinearity of conventional materials,building integrated photonic com-puting chips under traditional von Neumann architecture has been a ***,we report a new all-optical comput-ing framework to realize ultrafast and ultralow-energy-consumption all-optical computing based on convolutional neural *** device is constructed from cascaded silicon Y-shaped waveguides with side-coupled silicon waveguide segments which we termed“weight modulators”to enable complete phase and amplitude control in each waveguide *** generic device concept can be used for equation solving,multifunctional logic operations as well as many other mathematical *** computing functions including transcendental equation solvers,multifarious logic gate operators,and half-adders were experimentally demonstrated to validate the all-optical computing *** time-of-flight of light through the network structure corresponds to an ultrafast computing time of the order of several picoseconds with an ultralow energy consumption of dozens of femtojoules per *** approach can be further expan-ded to fulfill other complex computing tasks based on non-von Neumann architectures and thus paves a new way for on-chip all-optical comp

关键词： convolutional neural networks all-optical computing mathematical operations cascaded silicon waveguides

Angle-selective perfect absorption with two-dimensional materials

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Light(Science & Applications) 2015年第1期4卷 59-64页

作者： Linxiao Zhu Fengyuan Liu Hongtao Lin juejun Hu Zongfu Yu Xinran wang Shanhui Fan Department of Applied Physics Stanford UniversityStanfordCA 94305USA National Laboratory of Solid State Microstructures School of Electronic Science and Engineering and Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210093China Department of Materials Science and Engineering Massachusetts Institute of TechnologyMA 02139USA Department of Electrical and Computer Engineering University of Wisconsin-MadisonMadisonWI 53706USA Department of Electrical Engineering Ginzton LaboratoryStanford UniversityStanfordCA 94305USA

Two-dimensional(2D)materials have great potential in photonic and optoelectronic ***,the relatively weak light absorption in 2D materials hinders their application in practical ***,we propose a general approach to achieve angleselective perfect light absorption in 2D *** a demonstration of the concept,we experimentally show giant light absorption by placing large-area single-layer graphene on a structure consisting of a chalcogenide layer atop a mirror and achieving a total absorption of 77.6%in the mid-infrared wavelength range(~13μm),where the graphene contributes a record-high 47.2%absorptivity of mid-infrared *** of such an angle-selective thin optical element is important for solar and thermal energy harvesting,photo-detection and sensing *** study points to a new opportunity to combine 2D materials with photonic structures to enable novel device applications.

关键词： angle-selective perfect absorption angle-selective thin optical element graphene mid-infrared two-dimensional materials

餐厨垃圾半固态发酵产Bt生物农药及其稳定性

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农业工程学报 2016年第5期32卷 268-273页

作者：邹惠张文毓姜林姚珏君梁竞汪群慧北京市环境保护科学研究院污染场地风险模拟与修复北京市重点试验室北京100037 北京科技大学环境工程系北京100083

为降低苏云金芽孢杆菌（Bacillus thuringiensis,Bt）生物农药的生产成本,该研究采用餐厨垃圾为原料半固态发酵生产Bt生物农药,并对其产物稳定性的影响因素进行了考察。结果表明,发酵48 h后半固态发酵样品中的伴孢晶体产率较相同体积的... 详细信息

为降低苏云金芽孢杆菌（Bacillus thuringiensis,Bt）生物农药的生产成本,该研究采用餐厨垃圾为原料半固态发酵生产Bt生物农药,并对其产物稳定性的影响因素进行了考察。结果表明,发酵48 h后半固态发酵样品中的伴孢晶体产率较相同体积的固态发酵样品和液态发酵样品分别提高了54%和162%。体系含盐量、p H值、温度及紫外线4种常见因素中,体系含盐量的变化对伴孢晶体稳定性的影响并不显著;温度对伴孢晶体稳定性的影响显著,但当体系温度在0～60℃间变化时,各组数据差异并不显著。p H值对伴孢晶体稳定性的影响显著,且各数据间存在显著性差异;紫外线对伴孢晶体稳定性影响极显著,试验表明,当伴孢晶体在紫外线（36 W,距离40 cm）下暴露3 h后,其毒力效价即下降50%。为进一步提高伴孢晶体的抗紫外能力,采用聚乳酸为载体包覆伴孢晶体制备缓释剂,结果表明该缓释农药可有效延缓晶体在紫外线照射下的失活速度,使其在紫外线照射72 h后仍然能保持85%的活性,较相同照射条件下的伴孢晶体原粉提高了10倍左右,并能在30 d的作用周期内稳定的释放伴孢晶体,该成果对Bt生物农药产品优化具有重要的应用价值。

关键词：发酵垃圾农药苏云金芽孢杆菌 Bt生物农药毒力效价

急性中心性浆液性脉络膜视网膜病变多波长炫彩图像特征观察

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中华实验眼科杂志 2021年第11期39卷 997-1002页

作者：何璐陈长征易佐慧子王晓玲许阿敏刘珏君武汉大学人民医院眼科中心 430060

目的采用多波长炫彩成像技术对急性中心性浆液性脉络膜视网膜病变(CSC)患者的黄斑区进行扫描,观察其图像特征。方法采用横断面研究,纳入2017年8月至2018年1月在武汉大学人民医院眼科中心确诊的急性CSC患者34例34眼。其中男21例21眼,女13... 详细信息

目的采用多波长炫彩成像技术对急性中心性浆液性脉络膜视网膜病变(CSC)患者的黄斑区进行扫描,观察其图像特征。方法采用横断面研究,纳入2017年8月至2018年1月在武汉大学人民医院眼科中心确诊的急性CSC患者34例34眼。其中男21例21眼,女13例13眼;年龄26~61岁,平均(37.41±9.35)岁;发病时间5~45 d,平均(12.00±2.29)d。采集患眼彩色眼底照相、荧光素眼底血管造影(FFA)联合吲哚菁绿血管造影(ICGA)、多波长炫彩成像、光相干断层扫描(SD-OCT)图像。分析同一患眼各眼底成像的特征,并比较多波长炫彩成像图像和彩色眼底照相图像上渗漏点和浆液性视网膜神经上皮脱离与FFA/ICGA和SD-OCT诊断的符合率。结果关于浆液性视网膜神经上皮脱离区在标准多波长炫彩成像图像和蓝绿加强图像上表现为边界清晰的绿色反光区者33眼,占97.06%,表现为浆液性神经上皮脱离但边界不清者1眼,占2.94%;在蓝光反射图像上呈弱反光区者17眼,占50%;在绿光反射图像上呈边界清晰的弱反光区32眼,占94.11%;在红外光图像上呈边界清晰的弱反光区者33眼,占97.06%。FFA荧光素渗漏点对应处SD-OCT检查显示,19眼表现为微小视网膜色素上皮层脱离(PED),占55.88%,12眼表现为视网膜色素上皮(RPE)光带粗糙,占35.29%,3眼表现为较大PED,占8.82%。关于RPE渗漏部位,在标准多波长炫彩成像图像和蓝绿加强图像上表现为神经上皮脱离区内的红色斑驳样改变者29眼,占85.29%;在蓝光反射图像上呈强反光斑点者2眼,占5.88%;在绿光反射上表现为强反光斑点者5眼,占14.70%;在红外光反射图像上表现为弱反光区中夹杂强反光斑点者33眼,占97.06%。标准多波长炫彩成像图像、蓝绿加强图像和红外光反射图像用于发现浆液性视网膜神经上皮脱离和渗漏点征象的符合率均明显高于彩色眼底照相图像,差异均有统计学意义(均P<0.05)。结论标准多波长炫彩成像图像、蓝绿加强图像和红外光反射图像均能较好地显示急性CSC病灶的渗漏点和视网膜神经上皮层脱离,绿色反射图像能较好地显示急性CSC视网膜神经上皮脱离。基于共聚焦激光扫描检眼镜技术的多波长炫彩成像可作为急性CSC的辅助诊断手段。

关键词：视网膜疾病/诊断中心性浆液性脉络膜视网膜病变多波长炫彩成像荧光素眼底血管造影

西安城市热岛效应下的垂直气象观测与结果分析

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灾害学 2022年第3期37卷 136-139页

作者：赵仙荣葛珏骏王宇鹏于春亮陕西大气探测技术保障中心陕西西安710014 西安交通大学人居环境与建筑工程学院陕西西安710049 中铁九局集团有限公司大连分公司辽宁大连116011

诸多研究指出城市内部热环境变化造成的热岛效应加剧了一系列城市气象灾害。在目前针对热岛效应的研究中,在垂直方向上的气象观测数据常难以获得。该文介绍了一项为期1年的城市热岛效应垂直方向特征观测工作。通过系留气球携带探空仪,... 详细信息

诸多研究指出城市内部热环境变化造成的热岛效应加剧了一系列城市气象灾害。在目前针对热岛效应的研究中,在垂直方向上的气象观测数据常难以获得。该文介绍了一项为期1年的城市热岛效应垂直方向特征观测工作。通过系留气球携带探空仪,对城市和郊区不同高度的气象参数展开观测。观测结果显示:夏季城市冠层热岛的影响高度在30 m以上;冬季由于城市热岛的存在,城市冠层夜间的逆温强度(0.8℃)小于郊区(1.8℃),但逆温持续时间比郊区更长。通过分析城市冠层热岛垂直结构的时空变化特征可解析西安城市气象灾害的形成机制,并提出了若干政策性防灾减灾建议。

关键词：城市热岛垂直气象监测气象灾害西安市

多光谱眼底分层成像在中心性浆液性脉络膜视网膜病变中的应用价值

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中华实验眼科杂志 2021年第12期39卷 1075-1079页

作者：何璐陈长征易佐慧子王晓玲许阿敏刘珏君武汉大学人民医院眼科中心 430060

目的探讨多光谱眼底分层成像(MSI)在中心性浆液性脉络膜视网膜病变(CSC)中的应用价值。方法采用诊断试验研究方法,收集2017年9月至2018年5月于武汉大学人民医院眼科中心就诊的黄斑疾病患者69例85眼,其中男62例77眼,女7例8眼;平均年龄(4... 详细信息

目的探讨多光谱眼底分层成像(MSI)在中心性浆液性脉络膜视网膜病变(CSC)中的应用价值。方法采用诊断试验研究方法,收集2017年9月至2018年5月于武汉大学人民医院眼科中心就诊的黄斑疾病患者69例85眼,其中男62例77眼,女7例8眼;平均年龄(48.0±11.2)岁。根据是否患CSC分为CSC组45例61眼和非CSC组24例24眼。采集所有患者彩色眼底照相、荧光素眼底血管造影(FFA)、吲哚菁绿眼底血管造影、频域光相干断层扫描和MSI图像。以FFA作为金标准,计算MSI诊断CSC的灵敏度、特异度、假阳性率、假阴性率、阳性预测值和阴性预测值,采用Kappa一致性检验评价MSI与FFA诊断CSC的一致性,评估MSI对CSC的诊断价值。结果MSI诊断CSC的灵敏度为88.5%,特异度为91.7%;假阳性率为8.3%,假阴性率为11.5%,阳性预测值为96.4%,阴性预测值为75.9%,Kappa值为0.754。MSI与FFA检查结果比较,差异无统计学意义(χ^(2)=1.780,P=0.180)。在MSI各个波长图像上,620~850 nm波长图像显示视网膜色素上皮(RPE)渗漏点效果更佳,呈高反射信号,590~810 nm波长图像显示浆液性神经上皮脱离区边界清晰,660~850 nm波长图像显示浆液性神经上皮脱离区外的RPE损害更清晰。结论MSI与FFA诊断CSC的一致性较好,可以作为CSC的一种有效的无创检查手段。

关键词：视网膜疾病/诊断中心性浆液性脉络膜视网膜病变荧光素血管造影术多光谱眼底分层成像