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Applying Hybrid Clustering in Pulsar Candidate Sifting with Multi-modality for FAST Survey

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Research in Astronomy and Astrophysics 2024年第3期24卷 283-296页

作者： Zi-Yi You Yun-Rong Pan Zhi Ma Li Zhang Shuo Xiao Dan-Dan Zhang Shi-Jun Dang ru-shuang zhao Pei Wang Ai-Jun Dong Jia-Tao Jiang Ji-Bing Leng Wei-An Li Si-Yao Li School of Physics and Electronic Science Guizhou Normal UniversityGuiyang 550025China Guizhou Provincial Key Laboratory of Radio Astronomy and Data Processing Guizhou Normal UniversityGuiyang 550025China College of Big Data and Information Engineering Guizhou UniversityGuiyang 550025China CAS Key Laboratory of FAST National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China Key Laboratory of Information and Computing Guizhou Province Guizhou Normal UniversityGuiyang 550001China School of Big data and Computer Science Guizhou Normal UniversityGuiyang 550025China Guizhou Software Engineering Research Center Guiyang 550000China

Pulsar search is always the basis of pulsar navigation,gravitational wave detection and other research ***,the volume of pulsar candidates collected by the Five-hundred-meter Aperture Spherical radio Telescope(FAST)shows an explosive growth rate that has brought challenges for its pulsar candidate filtering ***,the multi-view heterogeneous data and class imbalance between true pulsars and non-pulsar candidates have negative effects on traditional single-modal supervised classification *** this study,a multi-modal and semi-supervised learning based on a pulsar candidate sifting algorithm is presented,which adopts a hybrid ensemble clustering scheme of density-based and partition-based methods combined with a feature-level fusion strategy for input data and a data partition strategy for *** on both High Time Resolution Universe SurveyⅡ(HTru2)and actual FAST observation data demonstrate that the proposed algorithm could excellently identify pulsars:On HTru2,the precision and recall rates of its parallel mode reach0.981 and 0.988 *** FAST data,those of its parallel mode reach 0.891 and 0.961,meanwhile,the running time also significantly decreases with the increment of parallel nodes within ***,we can conclude that our algorithm could be a feasible idea for large scale pulsar candidate sifting for FAST drift scan observation.

关键词： methods data analysis-surveys-methods numerical

One large glitch in PSR B1737-30 detected with the TMRT

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Research in Astronomy and Astrophysics 2019年第5期19卷 113-122页

作者： Jie Liu Zhen Yan Jian-Ping Yuan ru-shuang zhao Zhi-Peng Huang Xin-Ji Wu Na Wang Zhi-Qiang Shen Shanghai Astronomical Observatory Chinese Academy of Sciences School of Physical Science and Technology ShanghaiTech University University of Chinese Academy of Sciences Key Laboratory of Radio Astronomy Chinese Academy of Sciences Xinjiang Astronomical Observatory Chinese Academy of Sciences School of Physics Peking University

One large glitch was detected in PSR B1737-30 using data spanning from MJD 57999 to 58406 obtained with the newly built Shanghai Tian Ma Radio Telescope(TMRT). The glitch took place at the time around MJD 58232.4 when the pulsar underwent an increase in the rotation frequency of △v about 1.38 × 10^(-6) Hz, corresponding to a fractional step change of △v/v～ 8.39 × 10^(-7). Post-glitch v gradually decreased to the pre-glitch value. The frequency derivative was observed to undergo a step change of about-9×10^(-16) s^(-2). Since July 1987, there have been 36 glitches already reported in PSR B1737-30 including this one. According to our analysis, the glitch size distribution is well described by a power law with an index of 1.13. The distribution of the interval between two adjacent glitches(waiting time △T) follows a Poisson probability density function. For PSR B1737-30, the interval is prone to be long after a large glitch. However, no correlation is found between glitch size and the interval since the previous glitch.

关键词： stars:neutron pulsars:general pulsars:individual:B1737-30

Conformation and Counterion Distribution of Polyelectrolyte in Solution as Viewed from Dielectric Approach

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Chinese Journal of Polymer Science 2024年第9期42卷 1278-1301,I0005页

作者： Kong-shuang zhao College of Chemistry Beijing Normal UniversityBeijing 100875China

Polyelectrolyte solutions are more variable than uncharged macromolecule due to electrical interaction between charged molecules and surrounding ***,the subject of polyelectrolyte solutions has attracted a wide range of interests in both basic and applied research,and has also been extensively ***,the understanding of the molecular dynamics and conformation of polyelectrolytes in solution remains to be deepened,and universal consensus on some key issues have not been *** methods have contributed to solving the above problems in different ways,including dielectric relaxation spectroscopy(DRS).In this perspective,we briefly reviewed the history of dielectric spectroscopic research on polyelectrolyte solution,with emphasis on summarizing our *** particular,we expound the characteristics of DRS and its ability to obtain the internal information of the system of ***,we evaluate the advantages and limitations of the dielectric method and discussed future prospects of this field.

关键词： Polyelectrolyte Dielectric relaxation spectroscopy Chain conformation Thermosensitive microgel PNIPAM microgel Spherical polyelectrolyte brushes

IQABC-Based Hybrid Deployment Algorithm for Mobile Robotic Agents Providing Network Coverage

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Tsinghua Science and Technology 2024年第2期29卷 589-604页

作者： shuang Xu Xiaojie Liu Dengao Li Jumin zhao College of Computer Science and Technology(College of Data Science) Taiyuan University of TechnologyTaiyuan 030024China Pengcheng Laboratory Shenzhen 518055China College of Information and Computer Taiyuan University of TechnologyTaiyuan 030024China

Working as aerial base stations,mobile robotic agents can be formed as a wireless robotic network to provide network services for on-ground mobile devices in a target ***,a challenging issue is how to deploy these mobile robotic agents to provide network services with good quality for more users,while considering the mobility of on-ground *** this paper,to solve this issue,we decouple the coverage problem into the vertical dimension and the horizontal dimension without any loss of optimization and introduce the network coverage model with maximum coverage ***,we propose a hybrid deployment algorithm based on the improved quick artificial bee *** algorithm is composed of a centralized deployment algorithm and a distributed *** proposed deployment algorithm deploy a given number of mobile robotic agents to provide network services for the on-ground devices that are independent and identically *** results have demonstrated that the proposed algorithm deploys agents appropriately to cover more ground area and provide better coverage uniformity.

关键词： wireless robotic networks network coverage deployment algorithm improved quick artificial bee colony

Development of a novel Eu^(3+)-doped tantalate red-emitting phosphor for w-LEDs application

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Journal of Rare Earths 2024年第8期42卷 1479-1488,I0003页

作者： Fan Zeng Jingjing ru Bing zhao Feiyun Guo Jianzhong Chen College of Chemistry and Materials Fujian Province University Key Laboratory of Green Energy and Environment CatalysisNingde Normal University.Ningde352100China School of Environment and Resources School of Carbon Neutral and Modern IndustryFujian Normal UniversityFuzhou350007China College of Information and Mechanical&Electrical Engineering Ningde Normal UniversityNingde352100China College of Chemistry Fuzhou UniversityFuzhou350108China

Two novel phosphors LiBa_(4(1-x))Eu_(4x)Ta_(3)O_(12)(H-LBTO:xEu^(3+)) and Li_(0.25)Ba_(1-x)Eu_(x)Ta_(0.75)O_(3)(C-LBTO:xEu^(3+))were prepared successfully by a molten salt *** transformation between these two structures was realized by changing the sintering temperature or changing the Eu^(3+) ions concentration,which was also demonstrated by the X-ray diffraction(XRD),scanning electron microscopy(SEM),diffuse reflectance spectra(DRS),and photoluminescence excitation(PLE) analyses,Both the sintering temperature and the Eu^(3+)ions doping concentration have significant impact on the formation of the crystal *** these phosphors sintered at 1023 K exhibit two major luminescence lines at 594 and 614 nm under nearuV light of 395 nm excitation,corresponding to Eu^(3+)ions typical transitions of ^(5)D_(0)→^(7)F_(1) and ^(5)D_(0)→^(7)F_(2).The optimum concentration of Eu^(3+) ions is 9 mol% for C-LBTO:xEu^(3+) samples and the quenching interaction type is the nearest-neighbor ion *** thermal stability of the C-LBTO:0.09Eu^(3+)sample was investigated in detail and the device application further suggests that C-LBTO:0.09Eu^(3+) can be used as a red phosphor for near-UV excited w-LEDs in lighting.

关键词： Phosphor Tantalate LED device Rare earths

Self-assembly Induced by Complexation of Diblock Copolyelectrolytes and Oppositely Charged Homopolymers

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Chinese Journal of Polymer Science 2024年第9期42卷 1321-1332,I0006页

作者： Ling zhao Zhi-Yuan Yin Jia-Di Jiang Er-Qiang Chen shuang Yang Beijing National Laboratory for Molecular Sciences Key Laboratory of Polymer Chemistry and Physics of Ministry of EducationCenter for Soft Mater Science and EngineeringCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing100871China Beijing National Laboratory for Molecular Sciences College of Chemistry and Molecular EngineeringPeking UniversityBeijing100871China

We investigate the solution self-assembly of a mixture of positively charged homopolymers and AB diblock copolymers,in which the A blocks are negatively charged,and the B blocks are *** electrostatic complexation between oppositely charged polymers drives the formation of many ordered *** microstructures and phase diagrams are calculated using self-consistent field theory(SCFT)based on an ion-pair model with an equilibrium constant K to characterize the strength of binding between positively and negatively charged *** effects of the charge ratio,representing the ratio of charges from the homopolymer over all charges from polymers in the system,on the ordered structure are systematically studied,both for hydrophobic and hydrophilic A *** charge ratio plays an important role in determining the phase boundaries in the phase diagram of salt concentration versus polymer *** also provide information about the varying tendency of the domain spacing and core size of the spherical phase when the charge ratio is changed,and the results are in good agreement with *** studies provide a deep understanding of the self-assembled microstructures of oppositely charged diblock copolymer-homopolymer systems.

关键词： Self-assembly Polyelectrolyte complexation Self-consistent field theory Ion-pair

Multi-stimuli-responsive aggregation-induced emission copper iodide cluster

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Science China Chemistry 2024年第4期67卷 1193-1197页

作者： Bo Li Yuan-Yuan Liu Peng Luo Ye-ru Liu Ying-Jun Chen Kai Li shuang-Quan Zang College of Chemistry and Pharmacy Engineering Nanyang Normal UniversityNanyang 473061China Green Catalysis Center and College of Chemistry Zhengzhou UniversityZhengzhou 450001China

Stimuli-responsive luminescent materials have attracted significant attention in the development of smart photoactive materials for both fundamental research and technological *** this work,a new copper iodide cluster(1)with aggregationinduced emission(AIE)characteristic,was obtained combining Cu_(4)I_(4) core with rhodamine B derivative ligand.1 has reversible and distinct multi-stimuli-responsive luminescence for external temperature,volatile organic compound,and mechanical ***,1 exhibited unusual large blue shift(84 nm)after being ground,which originated from the change of intermolecular ***,1 exhibits high oxygen quenching efficiency for 82.2% at 1 *** studies showed that the multi-stimuli-responsive luminescence properties of 1 can be attributed to the regulation of cluster-centered luminescence process,metal-to-ligand charge transfer process,halide-to-metal charge transfer luminescence process and aggregationinduced barrier to oxygen *** work not only reports an AIE copper iodide cluster,but also provides a new strategy to develop multi-stimuli-responsive luminescence materials.

关键词： copper iodide cluster aggregation-induced emission multi-stimuli-response

Activable Photodynamic DNA Probe with an“AND”Logic Gate for Precision Skin Cancer Therapy

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Research 2024年第3期2024卷 735-750页

作者： Jiaojiao Zhu Lanyuan Peng Shah Jehan Haiyang Wang Xiang Chen shuang zhao Wenhu Zhou Xiangya School of Pharmaceutical Sciences Central South UniversityChangshaHunan 410013China Department of Dermatology Hunan Engineering Research Center of Skin Health and DiseaseHunan Key Laboratory of Skin Cancer and PsoriasisXiangya HospitalCentral South UniversityChangshaHunan 410008China Key Laboratory of Biological Nanotechnology of National Health Commission ChangshaHunan 410008China. Furong Laboratory ChangshaHunanChina Department of Vascular Surgery The First Affiliated Hospital of Guangzhou Medical UniversityGuangzhouGuangdong 510120China.

Photodynamic therapy(PDT)has emerged as a promising approach for squamous cell carcinoma treatment but hindered by tumor hypoxia,acquired resistance,phototoxicity,and so *** address these issues,we developed a smart strategy utilizing activable photosensitizers delivered by an aptamer-functionalized DNA probe(ADP).The ADP incorporated an AS1411 aptamer for tumor targeting and a linear antisense oligonucleotide(ASO)for recognition of Survivin *** the absence of the target,PDT remained quenched,thereby avoiding phototoxicity during circulation and nonselective *** the aid of the aptamer,ADP achieved selective targeting of *** internalization,ADP targeted recognized Survivin mRNA,triggering PDT activation,and releasing ASO to down-regulate Survivin expression and reverse tumor ***,the activable photosensitizers exhibited an“AND”logic gate,combining tumor-targeting delivery and tumor-related gene activation,thus enhancing its ***,the incorporation of hemin into the ADP provided catalase activity,converting tumor-abundant H_(2)O_(2) into O_(2),thereby ameliorating tumor *** resulting functionalized G-quadruplex/hemin–DNA probe complex demonstrated targeted delivery and activation,minimized side effects,and enhanced PDT efficacy in both xenograft tumor-bearing mice and patient-derived xenograft *** study offers a unique and promising platform for efficient and safe PDT,thus holding great potential for future clinical translation and improved cancer therapy.

关键词： specificity thereby Skin

Deep learning-based channel estimation for wireless ultraviolet MIMO communication systems

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Optoelectronics Letters 2024年第1期20卷 35-41页

作者： zhao Taifei SUN Yuxin Lü Xinzhe ZHANG shuang Faculty of Automation and Information Engineering Xi'an University of TechnologyXi'an 710048China Xian Key Laboratory of Wireless Optical Communication and Network Research Xi'an 710048China

To solve the problems of pulse broadening and channel fading caused by atmospheric scattering and turbulence,multiple-input multiple-output(MIMO)technology is a valid way.A wireless ultraviolet(UV)MIMO channel estimation approach based on deep learning is provided in this *** deep learning is used to convert the channel estimation into the image *** combining convolutional neural network(CNN)and attention mechanism(AM),the learning model is designed to extract the depth features of channel state information(CSI).The simulation results show that the approach proposed in this paper can perform channel estimation effectively for UV MIMO communication and can better suppress the fading caused by scattering and turbulence in the MIMO scattering channel.

关键词： channel scattering MIMO