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The Bright Single Pulse Emission from PSR B1133+16

Research in Astronomy and Astrophysics 2024年第4期24卷 253-261页

作者： Jun Tan zhi-gang wen Zhen Wang Xue-Feng Duan Hong-Guang Wang Na Wang Vishal Gajjar Jian-Ping Yuan Rai Yuen wen-Ming Yan Jian-Ling Chen Wei Han Hui Wang Cheng-Bing Lyu Ai-Jun Dong Maths and Information Technology School Yuncheng UniversityYuncheng 044000China Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China Xinjiang Key Laboratory of Radio Astrophysics Urumqi 830011China School of Physics and Materials Science Guangzhou UniversityGuangzhou 510006China Space Science Laboratory University of CaliforniaBerkeley 94710USA Department of Physics and Electronic Engineering Yuncheng UniversityYuncheng 044000China School of Physics and Electronic Science Guizhou Normal UniversityGuiyang 550025China

We have conducted a comprehensive investigation into the bright single pulse emission from PSR B1133+16using the Giant Metrewave Radio *** time resolution data(61μs)were obtained at a center frequency of 322 MHz with a bandwidth of 32 MHz over a continuous observation period of 7.45 hr.A total of 1082 bright pulses were sporadically detected with peak flux densities ranging from 10 to 23 times stronger than the average pulse ***,no giant pulse-like emission with a relative pulse energy larger than 10 and extremely short duration was detected,indicating that these bright pulses cannot be categorized as giant pulse *** majority of these bright pulses are concentrated in pulse phases at both the leading and trailing windows of the average pulse profile,with an occurrence ratio of approximately *** pulse energy distribution for all individual pulses can be described by a combination of two Gaussian components and a cutoff power-law with an index of α=-*** updated nulling fraction of 15.35%±0.45% was determined from the energy *** emission of individual pulses follows a log-normal distribution in peak flux density *** is imperative that regular phase drifting in bright pulse sequence is identified in both the leading and trailing components for the first *** physical mechanisms are discussed in detail to provide insights into these observations.

关键词： (stars:)pulsars:general (stars:)pulsars:individual(PSR B1133+16) methods:observational methods:data analysis

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Existence of Solutions for p-Laplace Equations Subjected to Neumann Boundary Value Problem

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Journal of China University of Mining and Technology 2006年第3期16卷 381-384页

作者： HU zhi-gang RUI wen-juan LIU wen-bing School of Sciences China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China

The existence of solutions for one dimensional p-Laplace equation （φp（u′））′=f（t,u,u′） with t∈（0,1） and Фp（s）=｜s｜^p-2 s, s≠0 subjected to Neumann boundary value problem at u′（0） = 0, u′（1） = 0. By using the degree theory, the sufficient conditions of the existence of solutions for p-Laplace equation subjected to Neumann boundary value condition are established.

关键词： p-Laplace equation neumann boundary value problem degree theory

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A Search for Radio Pulsars in Supernova Remnants Using FAST with One Pulsar Discovered

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Chinese Physics Letters 2024年第2期41卷 133-136页

作者：张振闫文明袁建平王娜白俊涛温志刚李保达解进涛赵德王榆斌翟楠楠 Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Radio Astronomy and Technology(Chinese Academy of Sciences) Beijing 100101China Xinjiang Key Laboratory of Radio Astrophysics Urumqi 830011China College of Physics GuiZhou UniversityGuizhou 550025China Research Center for Intelligent Computing Platforms Zhejiang LaboratoryHangzhou 311100China School of Physical Science and Technology Xinjiang UniversityUrumqi 830046China School of Physics and Electronic Engineering Sichuan University of Science&EngineeringZigong 643000China

We report the results of a search for radio pulsars in five supernova remnants(SNRs)with the FAST *** observations were made using the 19-beam receiver in“snapshot”*** integration time for each pointing was 10 *** discovered a new pulsar,PSR J1845–0306,which has a spin period of 983.6 ms and a dispersion measure of 444.6±2.0 cm^(−3)·pc,in observations of SNR G29.6+*** judge the association between the pulsar and the SNR,further verification is *** also re-detected some known pulsars in the data from SNRs G29.6+0.1 and G29.7–*** pulsars were detected in the observations of the other three SNRs.

关键词： observations Pulsar pulsar

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Dynamic evolution characteristics of the “source-reservoir” integration of gray marl and its geological significance to unconventional gas: Insights from pyrolysis experiments

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Petroleum Science 2023年第2期20卷 705-720页

作者： Zhang-Hu Wang Zhong-Liang Ma Lun-Ju Zheng Jun-Yu Wang zhi-gang wen Chen-Yang Si Cooperative Innovation Center of Unconventional Oil and Gas Yangtze UniversityWuhanHubei430100China Key Laboratory of Oil and Gas Resources and Exploration Technology Ministry of EducationCollege of Resources and EnvironmentYangtze UniversityWuhanHubei430100China Wuxi Research Institute of Petroleum Geology Sinopec Exploration and Production Research InstituteWuxiJiangsu214126China State Key Laboratory of Shale Oil and Gas Enrichment Mechanisms and Effective Development WuxiJiangsu214126China School of Metallurgy and Environment Central South UniversityChangshaHunan410083China

The marl–limestone rhythmic strata of the Permian Maokou Formation have been identified as hosts of unconventional gas reservoirs with “source–reservoir” integration. The lack of research on the pore structure evolution of organic-rich carbonate rock restricts gas exploration of these strata. Here, pyrolysis experiments were performed on the Mao-1 carbonate to simulate hydrocarbon generation, expulsion and diagenesis in gray marl from low maturity to overmaturity. The pore structure of this marl is dominated by mesopores and macropores, and the proportion of macropores increases gradually with temperature. The macropores are mainly pores in the organic matter and shrinkage microcracks. Additionally, micropores and mesopores, dominated by clay mineral interlayer pores and pyrite intergranular pores, are developed in the high mature stage and subsequently compressed in the overmature stage. The main contributors to the specific surface area are micropores and mesopores, which are conducive to natural gas adsorption. After the same pyrolysis treatment, the available porosity of grey marl is higher than that of marine/lacustrine shales, and exhibits an obvious decrease in the low mature–mature stage. These suggest that the abundant residual oil generated blocked the organic and inorganic pores in the gray marl, providing a pivotal material foundation for the gas generation. Micropores and mesopores developed during the high mature stage ensure the gas accumulation and preservation. The above indicate the organic-rich carbonate at the high mature–overmature stage (Ro = 1.7%–2.5%) in the Sichuan Basin may be a favorable exploration horizon for unconventional oil and gas.

关键词： Residual oil Organic pores Porosity Sepiolite Hydrocarbon generation

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Energy partition in laser-induced cavitation bubbles near the rigid wall with a gas-containing hole

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Journal of Hydrodynamics 2024年第3期36卷 435-443页

作者： Dong-qiao He Hai-gang wen Si-yuan Geng Chen-xi Yang Qiang Zhong zhi-feng Yao College of Water Resources and Civil Engineering China Agricultural UniversityBeijing100083China PowerChina Beijing Engineering Corporation Limited Beijing100024China State Key Laboratory of Efficient Utilization of Agricultural Water Resources Beijing100083China Beijing Engineering Research Center of Safety and Energy Saving Technology for Water Supply Network System China Agricultural UniversityBeijing100083China

To investigate the energy partition in laser-induced cavitation bubbles near the rigid wall with a gas-containing hole,we utilized a nanosecond resolution photography system based on a Q-switched Nd:YAG laser and conventional industrial camera to carefully observe the transient process of bubble collapse near the rigid wall with a gas-containing *** analyzed the generation of collapse microjets and the emission of collapse shock *** found that the cavitation bubble near the rigid wall with a gas-containing hole collapsed at different times and space,and produced various types of shock *** on the far field pressure information of the shock waves measured by hydrophone,the energy of the shock waves generated by the bubble collapse near the rigid wall with a gas-containing hole is calculated for the first *** results show that the ratio of collapse shock wave energy to bubble energy is approximately between 0.7 and 0.8.

关键词： Energy partition bubble collapse laser-induced shock wave gas-containing hole

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Community structure and species diversity dynamics of a subtropical evergreen broad-leaved forest in China:2005 to 2020

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Plant Diversity 2024年第1期46卷 70-77页

作者： Shi-Guang Wei Lin Li Kun-Dong Bai zhi-Feng wen Jing-gang Zhou Qin Lin Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection(Guangxi Normal University) Ministry of EducationGuilin 541004GuangxiChina School of Life&Environmental Sciences Guilin University of Electronic TechnologyGuilin 541004GuangxiChina Guangxi Key Laboratory of Landscape Resources Conservation and Sustainable Utilization in Lijiang River Basin Guilin 541004GuangxiChina Key Laboratory of Vegetation Restoration and Management of South China Botanical Garden of Degraded Ecosystems Chinese Academy of SciencesGuangzhou 510650GuangdongChina Center of Plant Ecology Core Botanical GardensChinese Academy of SciencesGuangzhou 510650GuangdongChina

Here,we characterize the temporal and spatial dynamics of forest community structure and species diversity in a subtropical evergreen broad-leaved forest in *** found that community structure in this forest changed over a 15-year ***,renewal and death of common species was large,with the renewal of individuals mainly concentrated within a few populations,especially those of Aidia canthioides and Cryptocarya *** numbers of individual deaths for common species were concentrated in the small and mid-diameter *** spatial distribution of community species diversity fluctuated in each monitoring period,showing a more dispersed diversity after the 15-year study period,and the coefficient of variation on quadrats *** 2010,the death and renewal of the community and the spatial variation of species diversity were different compared to other survey *** weather may have affected species regeneration and community stability in our subtropical monsoon evergreen broad-leaved *** findings suggest that strengthening the monitoring and management of the forest community will help better understand the long-and short-term causes of dynamic fluctuations of community structure and species diversity,and reveal the factors that drive changes in community structure.

关键词： Community structure Death and renewal dynamics Species diversity dynamics South subtropical forest

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Spin-down and emission variations for PSR J0742-2822

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Research in Astronomy and Astrophysics 2021年第2期21卷 142-148页

作者： Shi-Jun Dang Na Wang Hui-Hui Wang Jian-Ping Yuan Lun-Hua Shang Rai Yuen Ming-Yu Ge Xia Zhou Shuang-Qiang Wang Fei-Fei Kou wen-Ming Yan Jing-Bo Wang zhi-gang wen Jun-Tao Bai zhi-Yong Liu Zu-Rong Zhou Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China University of Chinese Academy of Sciences 19A Yuquan RoadBeijing 100049China Key Laboratory of Radio Astronomy Chinese Academy of SciencesNanjing 210008China School of Physics Huazhong University of Science and TechnologyWuhan 430074China School of Electronic and Optical Engineering Nanjing University of Science and TechnologyNanjing 210094China Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China CAS Key Laboratory of FAST National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China School of Physics and Electronic Science Guizhou Normal UniversityGuiyang 550001China Guizhou Provincial Key Laboratory of Radio Astronomy and Data Processing Guizhou Normal UniversityGuiyang 550001China

PSR J0742-2822 is known for its quasi-periodic changes in the observed pulse profile and spindown *** this paper,we analyzed 13 years of timing data obtained with the Nanshan 25-m radio telescope and the Parkes 64-m radio *** found that the average values of the spin-down rate((v))of this pulsar changed in four different *** investigated the correlation between v and W50,and ascertained that the correlation changed in different ***,not all the changes in states and correlation can be associated with glitch *** examined the long term evolution ofγ-ray flux(0.1-300 GeV)and the pulse profiles corresponding to the four different states using Fermi-LAT Pass8(P8 R3)data from 2008 August 5 to 2019 October *** did not detect a significant change inγ-ray flux or the pulse *** results suggest that the connection between pulsar rotation and emission is more complex than previously reported for this pulsar.

关键词： pulsars general-stars pulsar-methods timing

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In-situ synthesis of quantum dots in the nucleus of live cells

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National Science Review 2024年第3期11卷 172-182页

作者： Yusi Hu zhi-gang Wang Haohao Fu Chuanzheng Zhou wensheng Cai Xueguang Shao Shu-Lin Liu Dai-wen Pang State Key Laboratory of Medicinal Chemical Biology Frontiers Science Centre for New Organic MatterTianjin Key Laboratory of Biosensing and Molecular Recognition Research Centre for Analytical Sciences College of Chemistry School of Medicine and Frontiers Science Centre for Cell Responses Nankai University Haihe Laboratory of Sustainable Chemical Transformations

The cell nucleus is the main site for the storage and replication of genetic material, and the synthesis of substances in the nucleus is rhythmic, regular and strictly regulated by physiological processes. However,whether exogenous substances, such as nanoparticles, can be synthesized in situ in the nucleus of live cells has not been reported. Here, we have achieved in-situ synthesis of CdSxSe1-xquantum dots（QDs） in the nucleus by regulation of the glutathione（GSH） metabolic pathway. High enrichment of GSH in the nucleus can be accomplished by the addition of GSH with the help of the Bcl-2 protein. Then, high-valence Se is reduced to low-valence Se by glutathione-reductase-catalyzed GSH, and interacts with the Cd precursor formed through Cd and thiol-rich proteins, eventually generating QDs in the nucleus. Our work contributes to a new understanding of the syntheses of substances in the cell nucleus and will pave the way for the development of advanced ‘supercells’.

关键词： glutathione live cell nucleus quantum dot intracellular synthesis

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CIC Filter Theory in DDC and Implementation by Using FPGA

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Wuhan University Journal of Natural Sciences 2004年第6期9卷 899-903页

作者： MAzhi-gang wenBi-yang ZHOUHao BAILi-yun SchoolofElectronicInformation WuhanUniversityWuhan430072HubeiChina

Cascade Integrator Comb(CIC) filter is the main part of the next generation High Frequency (HF) radar. This paper describes the key points of CIC theory in the Digital Down Conversion (DDC) module of a radar receiver, and takes advantage of the high flexibility and high density feature of Field Programmable Gate Array (FPGA) for putting forth to design the CIC filter by using FPGA. This paper provides particular insight into design by FPGA, which has advantages in high speed operation and simply structure. Some important and practical applications are given in this paper. The simulation result proves the validity and veracity. Because we can adjust the parameters freely according to our need, the CIC filter can be adapted to the next generation HF radar. Key words FPGA - DDC - CIC filter - HF radar CLC number TN 47 Foundation item: Supported by the 863 High Technology Project of China(2001AA631050)Biography: MA zhi-gang(1978-), male, Ph. D candidate, research direction: software radio and EDA design.

关键词： FPGA DDC CIC filter HF radar

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Equivalence between the internal observability and equation

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Applied Mathematics(A Journal of Chinese Universities) 2024年第1期39卷 89-97页

作者： LIU wen-jun TU zhi-yu School of Mathematics and Statistics Nanjing University of Information Science and TechnologyNanjing 210044China

This paper is concerned with a third order in time linear Moore-Gibson-Thompson equation which describes the acoustic velocity potential in ultrasound wave *** by the work of Kaltenbacher,Lasiecka and Marchand(Control Cybernet.2011,40:971-988),we establish an observability inequality of the conservative problem,and then discuss the equivalence between the exponential stabilization of a dissipative system and the internal observational inequality of the corresponding conservative system.

关键词： Moore-Gibson-Thompson equation internal observability exponential stability

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