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A mathematical method for the de-dispersion of the pulsar profile

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Science china(Physics,Mechanics & Astronomy) 2010年第S1期53卷 228-230页

作者： yuan jianping1,2,wang na1,WU XinJi3 & ESAMDIN Ali1 1 urumqi observatory,national Astronomical Obsevatories,urumqi 830011,china 2 Graduate University of the Chinese Academy of Sciences,Beijing 100049,china 3 Department of Astronomy,Peking University,Beijing 100871,china 1. urumqi observatory National Astronomical Obsevatories Urumqi 830011 China 2. Graduate University of the Chinese Academy of Sciences Beijing 100049 China 3. Department of Astronomy Peking University Beijing 100871 China

This paper presents a mathematical method for de-dispersion of average pulsar *** applied this method to four dispersed pulsar *** results revealed that this method significantly removed the dispersion broadening and ... 详细信息

关键词： pulsar dispersion measure interstellar medium

Statistical study of the pulse width distribution for radio pulsars

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Science china(Physics,Mechanics & Astronomy) 2010年第S1期53卷 220-223页

作者： CHEN JianLing1,2,wang na1,yuan jianping1,2,wang HongGuang3,YAN WenMing1,2 & LIU ZhiYong1 1 urumqi observatory,national Astronomical Obsevatories,Chinese Academy of Sciences,urumqi 830011,china 2 Graduate University of the Chinese Academy of Sciences,Beijing 100049,china 3 Center for Astrophysics,Guangzhou University,Guangzhou 510006,china 1. urumqi observatory National Astronomical Obsevatories Chinese Academy of Sciences Urumqi 830011 China 2. Graduate University of the Chinese Academy of Sciences Beijing 100049 China 3. Center for Astrophysics Guangzhou University Guangzhou 510006 China

Pulse widths of standard pulse profiles for 262 pulsars were measured by using the urumqi 25 m radio telescope at 1.54 *** the simplest case of circular emission beam,we applied Monte Carlo simulations to the pulse width *** density functions of magnetic inclination angle α and observer angle ξ were *** Kolmogorov-Smirnov tests,we derived the most probable distribution for α and ξ.

关键词： pulsar pulse width emission beam random distribution

Stabilization or degradation?Post-translational modifications of JAZ proteins in plants

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Molecular Plant 2024年第7期17卷 1002-1004页

作者： Xiaoyan Xu jianping Hu Zheng yuan Joint International Research Laboratory of Metabolic&Developmental Sciences School of Life Sciences and BiotechnologyShanghai Jiao Tong UniversityShanghai200240China Department of Energy Plant Research Laboratory and Plant Biology Department Michigan State UniversityEast LansingMI 48824USA

Jasmonates(JAs)are essential hormones that regulate plant responses to biotic and abiotic stresses and are involved in various developmental processes,including flowering time control,floral organ development,and fertility of male and female gametes(Howe et al.,2018).However,our understanding of the mechanisms by which JAs integrate multiple signals to regulate diverse physiological processes remains *** the canonical JA signaling pathway,activated JAs are perceived by the F-box protein receptor COROnaTINE INSENSITIVE 1(COl1),which induces the interaction between COl1 and the Jas domain of the repressor proteins JASMOnaTE-ZIM DOMAIN PROTEINs(JAZs),leading to the ubiquitination and degradation of JAZ *** proteolytic destruction of the JAZ repressors is a crucial step that releases the inhibition of JAZs on the JA response transcription factor MYC2,allowing MYC2 to activate the expression of downstream genes(Howe et al.,2018).Therefore,the stability and specific spatiotemporal expression pattern of the JAZ proteins are critical for the regulation of JA signaling output,as they determine the activation and repression of JA responses.

关键词： translational fertility release

Delineation of urban growth boundary based on FLUS model under the perspective of land use evaluation in hilly mountainous areas

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Journal of Mountain Science 2024年第5期21卷 1647-1662页

作者： ZHANG Yunping LIN jianping HUANG Yimin CHEN Zebin ZHU Chenhui yuan Hao School of Geography and Environmental Engineering Gannan Normal UniversityGanzhou 341000China Key Laboratory of Low Carbon Recycling Technology for Municipal Solid Waste in Jiangxi Province Ganzhou 341000China

With rapid economic development,the size of urban land in china is expanding *** Urban Growth Boundary(UGB)is an expandable spatial boundary for urban construction in a certain period in order to control the urban *** delineation of UGB can inhibit the disorderly spread of urban space and guide the normal development of the *** is of practical significance for the construction of green urban *** study utilizes GIS technology to establish a land construction suitability evaluation system for nankang city,which is experiencing rapid urban expansion,and outlines the preliminary UGB under the future land use simulation(FLUS)*** the same time,considering the coupled coordination of"Production-Living-Ecological Space",and based on the suitability evaluation,we revised the preliminary UGB by combining the advantages of the patch-generating land use simulation(PLUS)model and the convex hull model to delineate the final *** results show that:1)the comprehensive score of the evaluation of the suitability of the construction of land from high to low shows the distribution of the center of the city to the surrounding circle type spread,the center of the city has the highest suitability *** results of convex hull model show that the urban expansion type of nankang is *** the future,the urban expansion will mainly occur in the northern part of the *** PLUS model predicts an increase of 3359.97 hm^(2)of construction land in nankang by 2035,of which 2022.97 hm^(2)is urban construction land.2)The FLUS model has a prediction accuracy of 86.3%and delineates a preliminary UGB area of 9215.07 hm^(2).3)We used the results of the construction suitability evaluation,PLUS model simulation results,and convex hull model predictions to revise the originally delineated *** final delineated UGB area is 8895.67 hm^(2)and it is capable of meeting the future development of the study *** results of the delineation can promote

关键词： Urban sprawl FLUS model Spatial correction Urban growth boundary Sustainable development

The Bright Single Pulse Emission from PSR B1133+16

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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

Recent study of emission line star 3G71

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Chinese Science Bulletin 1998年第6期43卷 470-473页

作者： HANG Hengrong 1,2 and XIA jianping+1 1. Purple Mountain observatory, Chinese Academy of Sciences, nanjing 210008, china 2. Joint Laboratory for Optical Astronomy, Chinese Academy of Sciences, nanjing 210008, china Purple Mountain observatory Chinese Academy of Sciences Nanjing China Joint Laboratory for Optical Astronomy Chinese Academy of Sciences Nanjing China

New spectral observations of 3G71 are presented. The main features of optical spectra which exhibit a lot of forbidden lines and unusual strong H-Balmer emission lines are discussed. Our data, together with its large IRAS infrared color excess and other characteristics, show evidence that the star may be a Herbig Ae/Be star rather than the optical counterpart of Be/X-ray source of 1H2214+589.

关键词： Be/X-ray binary emission line IRAS identification Herbig Ae/Be star.

The new model of fitting the spectral energy distributions of Mrk 421 and Mrk 501

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Science china(Physics,Mechanics & Astronomy) 2010年第S1期53卷 173-176页

作者： GAO XiaoYan1,wang JianCheng1 & YANG jianping1,2 1 national Astronomical Observatories/Yunnan observatory,key Laboratory for the structure and Evolcetion of Celestical Objects,Chinese Academy of Sciences,Kunming 650011,china 2 Yunnan Agricultural University,Kunming 650201,china 1. national Astronomical Observatories/Yunnan observatory key Laboratory for the structure and Evolcetion of Celestical Objects Chinese Academy of Sciences Kunming 650011 China2. Yunnan Agricultural University Kunming 650201 China

The spectral energy distribution(SED) of TeV blazars has a double-humped shape that is usually interpreted as a Synchrotron Self Compton(SSC) *** one zone SSC model is used broadly but cannot fit the high energy tail of SED very *** needs a bulk Lorentz factor which is in conflict with the ***,a one zone SSC model cannot explain the entire *** propose a new model where the high energy emission is produced by the accelerated protons in the blob with a small size and high magnetic field,and the low energy radiation comes from the electrons in the expanded *** the high and low energy photons are not produced at the same time,the requirement of a large Doppler factor from pair production is *** present the fitting results of the SEDs for Mrk 501 during April 1997 and Mrk 421 during March 2001.

关键词： GN blazar jet SPB model SSC

Arabian Peninsula-North Pacific Oscillation and its association with the Asian summer monsoon

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Science china Earth Sciences 2008年第7期51卷 1001-1012页

作者： SUN JianQi1, yuan Wei2 & GAO YuZhong3 1 nansen-Zhu International Research Centre, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, china 2 china Meteorological Administration Training Centre, Beijing 100081, china 3 Heilongjiang Meteorological observatory, Harbin 150030, china 1. nansen-Zhu International Research Centre Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China 2. china Meteorological Administration Training Centre Beijing 100081 China 3. Heilongjiang Meteorological observatory Harbin 150030 China

Using correlation and EOF analyses on sea level pressure from 57-year NCEP-NCAR reanalysis data, the Arabian Peninsula-North Pacific Oscillation (APNPO) is identified. The APNPO reflects the co-variability between the North Pacific high and South Asian summer monsoon low. This teleconnec- tion pattern is closely related to the Asian summer monsoon. On interannual timescale, it co-varies with both the East Asian summer monsoon (EASM) and South Asian summer monsoon (SASM); on decadal timescale, it co-varies with the EASM: both exhibit two abrupt climate changes in the middle 1960s and the late 1970s respectively. The possible physical process for the connections between the APNPO and Asian summer monsoon is then explored by analyzing the APNPO-related atmospheric circulations. The results show that with a strong APNPO, the Somali Jet, SASM flow, EASM flow, and South Asian high are all enhanced, and an anomalous anticyclone is produced at the upper level over northeast china via a zonal wave train. Meanwhile, the moisture transportation to the Asian monsoon regions is also strengthened in a strong APNPO year, leading to a strong moisture convergence over India and northern china. All these changes of circulations and moisture conditions finally result in an anoma- lous Asian summer monsoon and monsoon rainfall over India and northern china. In addition, the APNPO has a good persistence from spring to summer. The spring APNPO is also significantly corre- lated with Asian summer monsoon variability. The spring APNPO might therefore provide valuable in- formation for the prediction of Asian summer monsoon.

关键词： Arabian Peninsula-North Pacific Oscillation East Asian summer monsoon South Asian summer monsoon wave train abrupt climate change

On the knee of Galactic cosmic rays in light of sub-TeV spectral hardenings

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Chinese Physics C 2018年第7期42卷 113-122页

作者： Yi-Qing Guo1 2 Qiang yuan1 3 1. Key Laboratory of Dark Matter and Space Astronomy Purple Mountain observatory Chinese Academy of Sciences nanjing 210008 china 2. Key Laboratory of Particle Astrophysics Institute of High Energy Physics Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of Sciences Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of Sciences School of Astronomy and Space Science University of Science and Technology of China

More than fifty years after the discovery of the knee in the cosmic ray （CR） spectra, its physical origin remains a mystery. This is partly due to the ambiguity of the energy spectra of individual components. Recently, direct measurements from several space experiments found significant spectral hardenings of CR nuclei at ~200 GV. A joint modeling of the direct and indirect measurements may help to understand the experimental systematics and the physics of the knee. In this work, we update the phenomenological ＂poly-gonato＂ model to include the spectral hardenings, with a changing spectral index of γ ＋ β·logE. This modification gives a reasonable description of the CR spectra in a wide energy range. However, the fits to different data sets give different results. We find that the fit to the AMS-02 and CREAM data slightly favors a relatively low energy knee of the light components. In such a case, the expected all-particle spectra under-shoot the data, which may require an extra component of CRs. The fits to AMS-02 data and the light component （H＋He） data from the Tibet ASγ/ARGO-YBJ/WFCTA and KASCADE experiments give consistent results with the all-particle spectra. We further propose a possible physical realization of such a ＂modified poly-gonato＂ model of spectral hardenings by means of spatially-dependent diffusion of CRs. We find reasonably good agreement between the model predictions and the data for CR spectra, the secondary-to-primary ratios, and the amplitude of anisotropies.

关键词： cosmic ray knee spectrum propagation