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A wideband,high-resolution vector spectrum analyzer for integrated photonics

Light(Science & Applications) 2024年第4期13卷 760-771页

作者： Yi-Han Luo Baoqi Shi Wei Sun Ruiyang Chen Sanli Huang Zhongkai Wang jinbao Long Chen Shen Zhichao Ye Hairun guo junqiu Liu International Quantum Academy 518048 ShenzhenChina. Shenzhen Institute for Quantum Science and Engineering Southern University of Science and Technology518055 ShenzhenChina. Department of Optics and Optical Engineering University of Science and Technology of China230026 HefeiChina. Hefei National Laboratory University of Science and Technology of China230088 HefeiChina. Qaleido Photonics 518048 ShenzhenChina. Key Laboratory of Specialty Fiber Optics and Optical Access Networks Shanghai University200444 ShanghaiChina

The analysis of optical spectra—emission or absorption—has been arguably the most powerful approach for discovering and understanding *** invention and development of many kinds of spectrometers have equipped us with versatile yet ultra-sensitive diagnostic tools for trace gas detection,isotope analysis,and resolving hyperfine structures of atoms and *** proliferating data and information,urgent and demanding requirements have been placed today on spectrum analysis with ever-increasing spectral bandwidth and frequency *** requirements are especially stringent for broadband laser sources that carry massive information and for dispersive devices used in information processing *** addition,spectrum analyzers are expected to probe the device’s phase response where extra information is *** we demonstrate a novel vector spectrum analyzer(VSA)that is capable of characterizing passive devices and active laser sources in one *** a dual-mode VSA can measure loss,phase response,and dispersion properties of passive *** also can coherently map a broadband laser spectrum into the RF *** VSA features a bandwidth of 55.1 THz(1260–1640 nm),a frequency resolution of 471 kHz,and a dynamic range of 56 ***,our fiber-based VSA is compact and *** requires neither high-speed modulators and photodetectors nor any active feedback ***,we employ our VSA for applications including characterization of integrated dispersive waveguides,mapping frequency comb spectra,and coherent light detection and ranging(LiDAR).Our VSA presents an innovative approach for device analysis and laser spectroscopy,and can play a critical role in future photonic systems and applications for sensing,communication,imaging,and quantum information processing.

关键词： spectrum resolution coherent

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Development of red phosphor Li_(8)CaLa_(2)Ta_(2)O_(13):Eu^(3+)for WLEDs and anti-counterfeiting applications

ChemPhysMater

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ChemPhysMater 2024年第2期3卷 194-203页

作者： jingjing Ru Fan Zeng Bing Zhao Chenqing Ye Tonghui Zhong Feiyun guo jianzhong Chen College of Chemistry and Materials Fujian Province University Key Laboratory of Green Energy and Environment CatalysisNingde Normal UniversityNingde 352100China School of Environment and Resources School of Carbon Neutral and Modern IndustryFujian Normal UniversityFuzhou 350007China College of Information and Mechanical&Electrical Engineering Ningde Normal UniversityNingde 352100China College of Chemistry Fuzhou UniversityFuzhou 350108China

A set of novel red phosphors Li_(8)CaLa_(2)Ta_(2)O_(13):Eu^(3+)(LCLTO:xEu^(3+))were successfully prepared using a solid-state reaction *** properties of the prepared samples,including phase purity,elemental composition,and morphology,were systematically investigated using X-ray diffraction,scanning electron microscopy,and diffuse reflectance spectroscopy *** 610 nm maximum emission peak is attributed to the^(5)D_(0)→^(7)F_(2)transition of Eu^(3+)ion under 394 nm *** all the LCLTO:xEu^(3+)phosphors,LCLTO:0.6Eu^(3+)showed the strongest emission intensity because of the concentration quenching effect of the electric dipole-dipole in-teraction among the Eu^(3+)ions,which was also demonstrated by the decay ***,the emission intensity of the optimal LCLTO:0.6Eu^(3+)phosphor,which exhibited a high internal quantum efficiency of 49.30%and excellent color purity of 96.79%,was approximately 2.29 times higher than that of commercial Y203:Eu^(3+)red *** thermal stability of the LCLTO:0.6Eu^(3+)sample with good color stability was meticulously *** fabricated white-light-emitting diode(WLED)exhibited a superior color-rendering index of Ra=82 and chromaticity coordinates of(0.3260,0.3639),suggesting that LCLTO:0.6Eu^(3+)has potential applicability in developing efficient and high-quality ***,the prepared LCLTO:0.6Eu^(3+)/PDMS composite film demonstrated exceptional flexural resistance and chemical stability,indicating considerable promise for practical anti-counterfeitingapplications.

关键词： Phosphor Tantalate Luminescence LED device

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Symmetric Variation of Monomers for Constructing 1D/2D Imine-Based Covalent Organic Frameworks

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CCS Chemistry 2024年第4期6卷 941-952页

作者： Pengzhong Shi Kai Wang Ziao Chen jiawei Wang Kaifu Lin Ngangnseh Leboh Solange Yanfeng Yue Zhiyong guo College of Materials Science and Engineering Fuzhou UniversityFuzhou 350108 Department of Chemistry Delaware State UniversityDoverDelaware 19901

Synthetic control of topology connectivity is the crowning achievement for covalent organic framework(COF)*** a large number of one-,two-,and three-dimensional(1D,2D,and 3D)COFs have been reported,their topology structure constructions are restricted to the use of symmetric monomers with the purpose of increasing the crystallinity and/or ***,three imine-linked COFs with different topology nets(namely,sql-b and sql-c)were constructed by symmetric variation of monomers via the condensation of a tetra-amine monomer with a D2h-symmetry and lower C_(2v)-symmetric dialdehyde monomers,bearing a phenolic hydroxyl group at different *** results indicated that a reasonable introduction of the phenolic hydroxyl group could effectively tune the topological structure of COFs at the molecular level during the crystallization ***,the remarkable difference in the dye uptake ability between these COF materials indicated that the fabricated specific pore geometries,as well as different steric hindrance and H-bonding interactions,played a pivotal role in accessing molecules in the ***,this work might boost the explorations of COF materials with expected topologies and pore geometries from conventional monomers through bottom-up synthesis methodology by molecular designing and engineering.

关键词： covalent organic framework topology/dimension regulation molecular symmetry substituent effect molecular sieving

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Kerr-AdS黑洞的基于独立联络形式拉氏量的守恒量

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四川大学学报（自然科学版） 2024年第1期61卷 149-154页

作者：王耀郭伟杰彭俊金贵州师范大学物理与电子科学学院贵阳550001 贵州师范大学贵州省射电天文数据处理重点实验室贵阳550001

基于爱因斯坦引力理论的独立联络形式,由诺特定理可以导出一个含任意参考背景仿射联络的推广Katz-Bicak-Lynden-Bell(KBL)势,借此得到一个守恒量定义式.本文把该定义式应用于渐近anti-de Sitter(AdS)且转动的Kerr-AdS黑洞时空的质量与... 详细信息

基于爱因斯坦引力理论的独立联络形式,由诺特定理可以导出一个含任意参考背景仿射联络的推广Katz-Bicak-Lynden-Bell(KBL)势,借此得到一个守恒量定义式.本文把该定义式应用于渐近anti-de Sitter(AdS)且转动的Kerr-AdS黑洞时空的质量与角动量的定义,给出了与其他标准方法一致的结果.特别地,本文首次构造了一个比通常KBL超势中的参考背景联络更具一般性的新联络,相关结果表明KBL方法中的参考背景联络不具有唯一性,而对它的基本要求就是保持理论的协变性.

关键词： Kerr-AdS黑洞引力场的守恒荷 KBL方法 Kerr黑洞

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Factors affecting meibomian gland area loss in symptomatic adults

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International journal of Ophthalmology(English edition) 2024年第6期17卷 1036-1041页

作者： Si-Cheng Ding jing-jing Su Qing Zhan jiao-Man Wang Fang Zheng Xu-Xuan Fang Dan Cheng Ping guo The Second Clinical Medical College Jinan UniversityShenzhen 518000Guangdong ProvinceChina Shenzhen Eye Hospital Jinan UniversityShenzhen Eye InstituteShenzhen 518040Guangdong ProvinceChina Department of Ophthalmology Jinzhou Medical UniversityJinzhou 121000Liaoning ProvinceChina

AIM:To characterize the distribution of meibomian gland(MG)area loss(MGL)and its relationship with demographic characteristics,mites,and ***:This retrospective observational study included patients who visited the Dry Eye Clinic of Shenzhen Eye Hospital between june 2020 and August *** patient characteristics,ocular symptoms,Demodex test results of the eyelid edges,and the results of a comprehensive ocular surface analysis were *** was analyzed using Image j ***:This study enrolled 1204 outpatients aged 20-80(40.70±13.44)y,including 357 males(29.65%)and 847 females(70.35%).The patients were classified into mild(n=155;12.87%),moderate(n=795;66.03%),severe(n=206;17.11%),and extremely severe(n=48;3.99%)MGL *** was significantly larger in female than in male(P=0.006).The degree of MGL also significantly differed in age(P<0.001)and the more numbers of mites with severity(P<0.001).Multivariate disordered multinomial logistic regression analysis identified that female sex,older age,secretory symptoms,and a large number of mites were risk factors for MGL(P<0.05).CONCLUSION:Patients with MGL are more likely to be older,female,more numbers of mites,and increased secretion.

关键词： meibomianglands aging sex symptomatology Demodex

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PSRDP:A Parallel Processing Method for Pulsar Baseband Data

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Research in Astronomy and Astrophysics 2024年第1期24卷 300-310页

作者： Ya-Zhou Zhang Hai-Long Zhang jie Wang Xin-Chen Ye Shuang-Qiang Wang Xu Du Han Wu Ting Zhang Shao-Cong guo Meng Zhang Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Radio Astronomy Chinese Academy of SciencesNanjing 210008China National Astronomical Data Center Beijing 100101China Southeast University Nanjing 211189China School of Cyber Science and Engineering Qufu Normal UniversityQufu 273165China

To address the problem of real-time processing of ultra-wide bandwidth pulsar baseband data,we designed and implemented a pulsar baseband data processing algorithm(PSRDP)based on GPU parallel computing *** can perform operations such as baseband data unpacking,channel separation,coherent dedispersion,Stokes detection,phase and folding period prediction,and folding integration in GPU *** tested the algorithm using the j0437-4715 pulsar baseband data generated by the CASPSR and Medusa backends of the Parkes,and the j0332+5434 pulsar baseband data generated by the self-developed backend of the Nan Shan Radio *** obtained the pulse profiles of each baseband *** experimental analysis,we have found that the pulse profiles generated by the PSRDP algorithm in this paper are essentially consistent with the processing results of Digital Signal Processing Software for Pulsar Astronomy(DSPSR),which verified the effectiveness of the PSRDP ***,using the same baseband data,we compared the processing speed of PSRDP with DSPSR,and the results showed that PSRDP was not slower than DSPSR in terms of *** theoretical and technical experience gained from the PSRDP algorithm research in this article lays a technical foundation for the real-time processing of QTT(Qi Tai radio Telescope)ultra-wide bandwidth pulsar baseband data.

关键词： (stars:)pulsars:general methods:data analysis techniques:miscellaneous

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Dinitrophenyl-oxadiazole compounds:Design strategy,synthesis,and properties of a series of new melt-cast explosives

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Defence Technology（防务技术） 2024年第5期35卷 100-107页

作者： Bao-long Kuang Ting-wei Wang Cong Li Mou Sun Qamar-un-Nisa Tariq Chao Zhang Zhi-ming Xie Zu-jia Lu jian-guo Zhang State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081China China Wuzhou Engineering Group CO. LTD.Beijing 100053China

Melt-cast explosives are the most widely used energetic materials in military composite explosives,researchers have been unremittingly exploring high-energy and insensitive melt-cast *** this work,a series of dinitrophenyl-oxadiazole compounds were designed and *** compounds have an ideal low melting point(80-97℃),good detonation performance(detonation velocity D=6455-6971 m/s,detonation pressure P=18-19 GPa)and extreme insensitive nature(impact sensitivity≥60 j,friction sensitivity>360 N).All these compounds were well characterized by nuclear magnetic resonance,fourier transform infrared spectroscopy,elemental *** 2,3 were unambiguously confirmed by X-ray single crystal diffraction *** a result,their overall properties are superior to traditional melt-cast explosives trinitrotoluene(TNT)and dinitroanisole(DNAN)which may have excellent potential applications in insensitive melt-cast explosives.

关键词： Dinitrophenyl-oxadiazole Melt-cast explosive Low sensitivity

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Meibomian glands segmentation in infrared images with limited annotation

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International journal of Ophthalmology(English edition) 2024年第3期17卷 401-407页

作者： jia-Wen Lin Ling-jie Lin Feng Lu Tai-Chen Lai jing Zou Lin-Ling guo Zhi-Ming Lin Li Li College of Computer and Data Science Fuzhou UniversityFuzhou 350108Fujian ProvinceChina Fujian Provincial Key Laboratory of Networking Computing and Intelligent Information Processing Fuzhou UniversityFuzhou 350108Fujian ProvinceChina Shengli Clinical Medical College of Fujian Medical University Fuzhou 350001Fujian ProvinceChina Department of Ophthalmology Fujian Provincial Hospital South BranchFujian Provincial HospitalFuzhou 350001Fujian ProvinceChina

●AIM:To investigate a pioneering framework for the segmentation of meibomian glands(MGs),using limited annotations to reduce the workload on ophthalmologists and enhance the efficiency of clinical diagnosis.●METHODS:Totally 203 infrared meibomian images from 138 patients with dry eye disease,accompanied by corresponding annotations,were gathered for the study.A rectified scribble-supervised gland segmentation(RSSGS)model,incorporating temporal ensemble prediction,uncertainty estimation,and a transformation equivariance constraint,was introduced to address constraints imposed by limited supervision information inherent in scribble *** viability and efficacy of the proposed model were assessed based on accuracy,intersection over union(IoU),and dice coefficient.●RESULTS:Using manual labels as the gold standard,RSSGS demonstrated outcomes with an accuracy of 93.54%,a dice coefficient of 78.02%,and an IoU of 64.18%.Notably,these performance metrics exceed the current weakly supervised state-of-the-art methods by 0.76%,2.06%,and 2.69%,***,despite achieving a substantial 80%reduction in annotation costs,it only lags behind fully annotated methods by 0.72%,1.51%,and 2.04%.●CONCLUSION:An innovative automatic segmentation model is developed for MGs in infrared eyelid images,using scribble annotation for *** model maintains an exceptionally high level of segmentation accuracy while substantially reducing training *** holds substantial utility for calculating clinical parameters,thereby greatly enhancing the diagnostic efficiency of ophthalmologists in evaluating meibomian gland dysfunction.

关键词： infrared meibomian glands images meibomian gland dysfunction meibomian glands segmentation weak supervision scribbled annotation

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Growth kinetics of titanium carbide coating by molten salt synthesis process on graphite sheet surface

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International journal of Minerals,Metallurgy and Materials 2024年第8期31卷 1858-1864页

作者： Xiaoyu Shi Chongxiao guo jiamiao Ni Songsong Yao Liqiang Wang Yue Liu Tongxiang Fan State Key Lab of Metal Matrix Composites School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China

The synthesis of carbide coatings on graphite substrates using molten salt synthesis(MSS),has garnered significant interest due to its cost-effective *** study investigates the reaction process and growth kinetics involved in MSS,shedding light on key aspects of the *** involvement of Ti powder through liquid-phase mass transfer is revealed,where the diffusion distance and quantity of Ti powder play a crucial role in determining the reaction rate by influencing the C content gradient on both sides of the ***,the growth kinetics of the carbide coating are predominantly governed by the diffusion behavior of C within the carbide layer,rather than the chemical reaction *** analyze the kinetics,the thickness of the carbide layer is measured with respect to heat treatment time and temperature,unveiling a parabolic relationship within the temperature range of 700-1300℃.The estimated activation energy for the reaction is determined to be 179283 j·mol^(-1).These findings offer valuable insights into the synthesis of carbide coatings via MSS,facilitating their optimization and enhancing our understanding of their growth mechanisms and properties for various applications.

关键词： titanium carbide graphite molten salt kinetic analysis

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Effect of surface layer softening from previous electrochemical corrosion on electrochemical cold drawing of Q235 steel bar

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journal of Iron and Steel Research(International) 2022年第5期29卷 819-835页

作者： j.L.guo T.j.Chen State Key Laboratory of Advanced Processing and Recycling of Nonferrous Metals Lanzhou University of TechnologyLanzhou730050GansuChina

The effects of H_(2)SO_(4)concentration and current in electrochemical corrosion on surface layer softening or plasticizing of Q235 steel bar and their effects on subsequent electrochemical cold drawing(ECD)were *** results indicate that the electrochemical corrosion can soften or plasticize the surface layer of Q235 steel bar and then make the subsequent ECD be conducted more *** softening degree and thickness of the surface layer are continuously enhanced with increasing corrosion rate,i.e.,increasing H_(2)SO_(4)concentration or current,due to the generation of more vacancy clusters in deeper regions of surface *** vacancy clusters then relax dislocations through being absorbed during ECD,and the formation and movement of additional dislocation flux are thereby enhanced,resulting in the further obvious decrease in the drawing *** is also due to the enhanced formation and movement of additional dislocation flux that the dislocation density and thus the hardness of the surface layer are decreased,as well as that the texture structure is *** behaviors are enhanced as the corrosion rate increases.

关键词： Electrochemical corrosion Electrochemical cold drawing Surface layer softening Vacancy Additional dislocation flux

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