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The synthesis of fluorescent nanoclusters based on the etching reaction

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Nano Research 2024年第5期17卷 4631-4638页

作者： Hongbin Lin Yitao Cao Qiaofeng yao Tiankai Chen Huiting Shan jianping Xie Joint School of National University of Singapore and Tianjin University International Campus of Tianjin UniversityFuzhou 350207China Department of Chemical and Biomolecular Engineering National University of SingaporeSingapore 117585Singapore National and Local Joint Engineering Research Center of MPTES in High Energy and Safety LIBs Engineering Research Center of MTEES(Ministry of Education)and Key Laboratory of ETESPG(GHEI)South China Normal UniversityGuangzhou 510006China Tianjin Key Laboratory of Molecular Optoelectronic Sciences Key Laboratory of Integrated Organic CircuitsMinistry of EducationDepartment of ChemistrySchool of ScienceTianjin UniversityTianjin 300072China

Thiolate-protected atomically precise nanoclusters(NCs)demonstrate a series of unique luminescent characteristics attributed to their various peculiar electronic structures.Therefore,fluorescent NCs present extraordinary practical values in biosensing and bioimaging research fields.Nevertheless,restricted by the types of fluorescent NCs,there are great difficulties in promoting the development of NCs in fluorescent research areas.As a result,it is of significant necessity for researchers to develop new synthetic pathways to produce high-quality fluorescent NCs.According to the analysis about the structural characteristics of fluorescent NCs,some general features like longer motif and higher ligand-to-metal ratio can be found,consistent to some presented regularities in etching reaction.Consequently,in this work,we used Au_(25)(MHA)_(18)(MHA=6-mercaptohexanoic acid)as a model nanocluster and utilized the etching reaction to systematically explore etching products and their corresponding luminescent properties.Moreover,we also identified three main reaction processes in the entire etching reaction process,which can generate new metal nanocluster species with various fluorescent properties.Hence,the etching reaction will provide a good platform to produce new luminescent metal NC species.

关键词： etching reaction metal nanoclusters fluorescent properties fluorescent conversion

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Microwave photonics

Science China(Information Sciences) 2022年第12期65卷 49-112页

作者： jianping yao Jose CAPMANY Microwave Photonics Research Laboratory School of Electrical Engineering and Computer Science University of Ottawa ITEAM Research Institute Universitat Politècnica de València iPronics Programmable Photonics

Microwave photonics, an interdisciplinary field that combines microwave engineering and photonic technology for the generation, transmission, processing, and control of microwave signals, to take advantage of the broad bandwidth, high frequency, and low loss offered by modern photonics, has been intensively researched for the last few decades, and numerous solutions have been proposed and demonstrated. In this article, an overview about microwave photonics is provided which covers the basic concepts of microwave photonics, photonic-assisted microwave signal generation, photonic-assisted microwave signal processing, and true time delay beamforming. The implementation of microwave photonic systems based on photonic integrated circuits is also reviewed, including the design, fabrication, and material platforms, application-specific photonic integrated circuits for microwave photonics, and programmable integrated microwave photonics.The challenges and future applications of microwave photonics are also discussed.

关键词： microwave photonics photonic integrated circuits microwave photonic link microwave photonic signal processor optoelectronic oscillator radio over fiber

The underappreciated role of fugitive VOCs in ozone formation and health risk assessment emitted from seven typical industries in China

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Journal of Environmental Sciences 2024年第2期136卷 647-657页

作者： Zhiling Liang Yunjiang Yu Bingbing Sun Qian yao Xihua Lin Yongsheng Wang jianping Zhang Yingzi Li Xuefeng Wang Zhengzheng Tang Shexia Ma College of Environmental and Chemical Engineering Shanghai University of Electric PowerShanghai 200090China State Environmental Protection Key Laboratory of Environmental Protection Health Risk Assessment South China Institute of Environmental SciencesMinistry of Ecology and EnvironmentGuangzhou 510535China Henan Jiyuan Ecological Environment Testing Center Jiyuan 454650China Ecological Environment Bureau of Jiyuan Production City Integration Demonstration Zone Jiyuan 454650China

Fugitive emission from industrial sources may result in ozone formation and health risk,while the exact contribution of this source remains incompletely understood.In this study,emission characteristics,ozone formation potential(OFP)and health risk of fugitive VOCs in7 representative industries were investigated.Chemical material industry was the dominant contributor to VOCs of fugitive emission in comparison with other industries.The OFP of VOCs from fugitive emission was in the range of 1.45×10^(3)-3.98×10^(5)μg/m^(3),with a higher value than that of organized emission in seven industries except for the coking industry and the chemical material industry,suggesting that fugitive VOCs should be taken into account while developing control strategies.Acetaldehyde,m,p-xylene,n-nonane,ethylene,vinyl chloridethe and other high OFP-contributing species were the major reactive species that should be targeted.Health risk assessment investigated non-cancer and cancer risks of fugitive VOCs in 7 industries were all above safe level(HR>1 and LCR>1×10^(-4)),posing remarkable health threats to human health.OVOCs were the main contributor to non-cancer risk,while halohydrocarbons and aromatics contributed most to cancer risks,posing remarkable health threat on human health.Our findings highlighted the contribution of fugitive VOCs on ozone formation and health risk was underestimated,indicating which should be considered in emission control strategies of industrial sources.

关键词： Industrial sources Volatile organic compounds Fugitive emission Ozone formation potential Health risk assessment

Ligand-dependent aggregation-enhanced photoacoustic of atomically precise metal nanocluster

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Aggregate

Aggregate 2024年第1期5卷 196-203页

作者： Changlin Zhou Meng Wang Qiaofeng yao Yu Zhou Chuantao Hou Jianfei Xia Zonghua Wang Jishi Chen jianping Xie College of Chemistry and Chemical Engineering Shandong Sino-Japanese Center for Collaborative Research of Carbon NanomaterialsInstrumental Analysis Center of Qingdao UniversityQingdao UniversityQingdaoP.R.China Tianjin Key Laboratory of Molecular Optoelectronic Sciences Department of ChemistrySchool of ScienceTianjin UniversityTianjinP.R.China Qingdao Boting Hydrogen Age Ocean Technol R&D Ctr. Qingdao Boting Technol Co.Ltd.Shandong Hydrogen Times Marine Technology Co.Ltd.QingdaoP.R.China Department of Chemical and Biomolecular Engineering National University of SingaporeSingapore Joint School of National University of Singapore and Tianjin University International Campus of Tianjin UniversityBinhai New CityFuzhouP.R.China

Atomically precise metal nanoclusters(MNCs),as a potential type of photoacoustic(PA)contrast agent,are limited in application due to their low PA conversion efficiency(PACE).Here,with hydrophilic Au25SR18(SR=thiolate)as model NCs,we present a result that weakly polar solvent induces aggregation,which effectively enhances PA intensity and PACE.The PA intensity and PACE are highly dependent on the degree of aggregation,while the aggregation-enhanced PA intensity(AEPA)positively correlates to the protected ligands.Such an AEPA phenomenon indicates that aggregation actually accelerates the intramolecular motion of Au NCs,and enlarges the proportion of excited state energy dissipated through vibrational relaxation.This result conflicts with the restriction of intramolecular motion mechanism of aggregation-induced emission.Further experiments show that the increased energy of AEPA originates from the aggregation inhibiting the intermolecular energy transfer from excited Au NCs to their surrounding medium molecules,including solvent molecule and dissolved oxygen,rather than restricting radiative relaxations.This study develops a new strategy for enhancing the PA intensity of Au NCs,and contributes to a deeper understanding of the origin of the PA signal and the excited state energy dissipation processes for MNCs.

关键词： aggregation-enhanced photoacoustic gold nanocluster intermolecular excited state energy transfer intramolecular motion ligand effect

Exceptional-point-enhanced sensing in an all-fiber bending sensor

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Opto-Electronic Advances 2023年第12期6卷 36-43页

作者： Zheng Li Jingxu Chen Lingzhi Li Jiejun Zhang jianping yao Guangdong Provincial Key Laboratory of Optical Fiber Sensing and Communications Institute of Photonics TechnologyJinan UniversityGuangzhou 510632China Microwave Photonics Research Laboratory School of Electrical Engineering and Computer ScienceUniversity of OttawaOttawaON K1N 6N5Canada

An exceptional-point(EP)enhanced fiber-optic bending sensor is reported.The sensor is implemented based on paritytime(PT)-symmetry using two coupled Fabry-Perot(FP)resonators consisting of three cascaded fiber Bragg gratings(FBGs)inscribed in an erbium-ytterbium co-doped fiber(EYDF).The EP is achieved by controlling the pumping power to manipulate the gain and loss of the gain and loss FP resonators.Once a bending force is applied to the gain FP resonator to make the operation of the system away from its EP,frequency splitting occurs,and the frequency spacing is a nonlinear function of the bending curvature,with an increased slope near the EP.Thus,by measuring the frequency spacing,the bending information is measured with increased sensitivity.To achieve high-speed and high-resolution interrogation,the optical spectral response of the sensor is converted to the microwave domain by implementing a dual-passband microwave-photonic filter(MPF),with the spacing between the two passbands equal to that of the frequency splitting.The proposed sensor is evaluated experimentally.A curvature sensing range from 0.28 to 2.74 m^(−1) is achieved with an accuracy of 7.56×10^(−4 )m^(−1 )and a sensitivity of 1.32 GHz/m^(−1),which is more than 4 times higher than those reported previously.

关键词： exceptional-point enhanced sensitivity bending sensor parity-time symmetry.

Consensus on rapid screening for prodromal Alzheimer's disease in China

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General Psychiatry 2024年第1期37卷 1-16页

作者： Lin Huang Qinjie Li yao Lu Fengfeng Pan Liang Cui Ying Wang Ya Miao Tianlu Chen Yatian Li Jingnan Wu Xiaochun Chen jianping Jia Qihao Guo Department of Gerontology Shanghai Sixth People's Hospital Afiliated to Shanghai Jiao Tong University School of MedicineShanghaiChina Center for Translational Medicine and Shanghai Key Laboratory of Diabetes Mellitus Shanghai Sixth People's Hospital Affiliated to Shanghai Jiao Tong University School of MedicineShanghaiChina shanghai BestCovered ShanghaiChina ADepartment of Neurology Fujan Medical University Union HospitalFuzhouChina Department of Neurology National Clinical Research Center for Geriatric DiseasesBeijingChina

Alzheimer's disease(AD)is a common cause of dementia,characterised by cerebral amyloid-βdeposition,pathological tau and neurodegeneration.The prodromal stage of AD(pAD)refers to patients with mild cognitive impairment(MCl)and evidence of AD's pathology.At this stage,disease-modifying interventions should be used to prevent the progression to dementia.Given the inherent heterogeneity of MCl,more specific biomarkers are needed to elucidate the underlying AD's pathology.Although the uses of cerebrospinal fluid and positron emission tomography are widely accepted methods for detecting AD's pathology,their clinical applications are limited by their high costs and invasiveness,particularly in low-income areas in China.Therefore,to improve the early detection of Alzheimer's disease(AD)pathology through cost-effective screening methods,a panel of 45neurologists,psychiatrists andgerontologistswas invited to establish a formal consensus on the screening of pAD in China.The supportive evidence and grades of recommendations are based on a systematic literature review andfocus group discussion.National meetings were held to allow participants to review,vote and provide their expert opinions to reach a consensus.A majority(two-thirds)decision was used for questions for which consensus could not be reached.Recommended screening methods are presented in this publication,including neuropsychological assessment,peripheral biomarkers and brain imaging.In addition,a general workflow for Screening pAD in China is established,which will help clinicians identify individuals at high risk and determine therapeutic targets.

关键词： Alzheimer income screening

4×4 multiple-input multiple-output coherent microwave photonic link with optical independent sideband and optical orthogonal modulation

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Chinese Optics Letters 2017年第1期15卷 33-39页

作者： Xiang Chen jianping yao Microwave Photonics Research Laboratory School of Electrical Engineering and Computer Science University of Ottawa Ottawa Ontario K1N 6N5 Canada

A 4× 4 multiple-input multiple-output coherent microwave photonic （MWP） link to transmit four wireless signals with an identical microwave center frequency over a single optical wavelength based on optical independent sideband （OISB） modulation and optical orthogonal modulation with an improved spectral efficiency is proposed and experimentally demonstrated. At the transmitter, the OISB modulation and optical orthogonal modulation are implemented to generate an OISB signal using a dual-parallel Mach-Zehnder modulator （DP- MZM） driven by four microwave orthogonal frequency-division multiplexing （OFDM） signals with an identical microwave center frequency. At the receiver, the OISB signal is coherently detected at a coherent receiver where a free-running local oscillator （LO） laser source is employed. Digital signal processing is then used to recover the four OFDM signals, to eliminate the phase noise from the transmitter laser source and the LO laser source, and to cancel the unstable wavelength difference between the wavelengths of the transmitter laser source and the LO laser source. Error-free transmission of three 16 quadrature amplitude modulation （16-QAM） 1 Gbps OFDM signals and one 16-QAM 1.5 Gbps OFDM signal at a microwave center frequency of 2.91 GHz over a 10 km single-mode fiber is experimentally demonstrated.

关键词： Fiber optics and optical communications Radio frequency photonics Heterodyne

致密砂岩储层微观孔喉结构及可动流体分布特征:以鄂尔多斯盆地东部神木地区盒8段储层为例

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地质科技通报 2024年第2期43卷 41-51页

作者：夏玉磊兰建平姚伟中国石油天然气集团川庆钻探工程有限公司长庆井下技术作业公司西安710018 中国石油天然气集团油气藏改造重点实验室-二氧化碳压裂增产研究室西安710018

致密砂岩复杂的孔喉结构导致多变的可动流体分布,而微观孔隙结构和可动流体分布又是研究致密砂岩储层的重点。基于核磁共振可动流体测试原理,采用离心试验、高压压汞、扫描电镜、X射线衍射及铸体薄片等方法,建立了神木地区盒8段储层孔... 详细信息

致密砂岩复杂的孔喉结构导致多变的可动流体分布,而微观孔隙结构和可动流体分布又是研究致密砂岩储层的重点。基于核磁共振可动流体测试原理,采用离心试验、高压压汞、扫描电镜、X射线衍射及铸体薄片等方法,建立了神木地区盒8段储层孔隙结构分类标准,明确了3类岩石孔隙结构参数及孔隙、喉道类型,提出了适用于目标储层转换系数的新方法,并定量评价了3类岩石可动流体分布特征。研究结果表明,目标储层中Ⅰ、Ⅱ类岩石孔隙以孔径大于10μm的残余粒间孔和孔径大于1μm的溶蚀孔为主,喉道以缩小型和弯片状喉道为主,孔隙结构参数较好,大孔隙发育程度高、孔喉间连通性好、可动流体赋存量大,大部分可动流体赋存于T_(2)谱右峰对应的大孔隙中,而左峰对应的小孔隙中可动流体含量低。Ⅲ类岩石孔隙结构参数差、可动流体百分比低、孔喉以晶间孔和管束状喉道为主。目标储层平均转换系数为0.029μm/ms,但Ⅰ、Ⅱ类岩石转换系数小于Ⅲ类,转换后的Ⅰ、Ⅱ类岩石T_(2)谱的右峰与压汞孔隙半径分布的主峰相对应,而Ⅲ类岩石T_(2)谱的左峰与压汞孔隙半径分布的主峰相对应。Ⅰ、Ⅱ类岩石孔径大于1μm的孔隙中可动流体百分比高,是未来勘探开发的主要方向。研究成果为提高致密油藏采收率提供了参考和借鉴。

关键词：致密砂岩储层高压压汞核磁共振可动流体微观孔喉结构

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Reconfigurable single-shot incoherent optical signal processing system for chirped microwave signal compression

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Science Bulletin 2017年第4期62卷 242-248页

作者： Ming Li Shuqian Sun Antonio Malacarne Sophie LaRochelle jianping yao Ninghua Zhu Jose Azana Institut National de la Recherche Scientifique-Energie Materiaux et Telecommunications(INRS-EMT)VarennesQuebec J3X 1S2Canada State Key Laboratory on Integrated Optoelectronics Institute of SemiconductorsChinese Academy of SciencesBeijing 100083China University of Chinese Academy of Sciences Beijing 100049China TeCIP Institute Scuolo Superiore Sant'AnnaPisa 56124Italy Center for Optics Photonics and Laser(COPL)Universite LavalQuebec G1V OA6Canada Microwave Photonics Research Laboratory University of OttawaOntario K1N 6N5Canada

We propose and demonstrate a reconfigurable and single-shot incoherent optical signal processing system for chirped microwave signal compression, using a programmable optical filter and a multiwavelength laser(MWL). The system is implemented by temporally modulating a specially shaped MWL followed by a suitable linear dispersive medium. A microwave dispersion value up to 1.33 ns/GHz over several GHz bandwidth is achieved based on this approach. Here we demonstrate a singleshot compression for different linearly chirped microwave signals over several GHz bandwidth. In addition, the robustness of the proposed system when input RF signals are largely distorted is also discussed.

关键词：信号处理系统微波信号线性啁啾非相干光信号压缩可重构多波长激光器可编程滤波器