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Galactic interstellar scintillation observed from four globular cluster pulsars by FAST

中国科学:物理学、力学、天文学英文版 2023年第9期66卷 119-127页

作者： Dandan Zhang Zhenzhao Tao Mao Yuan jumei yao Pei Wang Qijun Zhi Weiwei Zhu Xun Shi Michael Kramer Di Li Lei Zhang Guangxing Li School of Mathematical Sciences School of Physics and Electronic SciencesGuizhou Normal UniversityGuiyang 550001China National Astronomical Observatories Chinese Academy of SciencesBeijing 100012China Guizhou Provincial Key Laboratory of Radio Astronomy and Data Processing Guiyang 550001China Department of Astronomy Beijing Normal UniversityBeijing 100875China Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China South-Western Institute for Astronomy Research(SWIFAR) Yunnan UniversityKunming 650000China Institute for Frontiers in Astronomy and Astrophysics Beijing Normal UniversityBeijing 102206China Max-Planck Institut fr Radioastronomie Bonn D-53121Germany Key Laboratory of Radio Astronomy and Technology Chinese Academy of SciencesBeijing 100101China Computational Astronomy Platform Zhejiang LabHangzhou 311121China

We report detections of scintillation arcs for pulsars in globular clusters M5,M13 and M15 for the first time using the Fivehundred-meter Aperture Spherical radio Telescope(FAST).From observations of these arcs at multiple epochs,we infer that screen-like scattering medium exists at distances 4.1_(-0.3)^(+0.2),6.7_(-0.2)^(+0.2)and 1.3_(-1.0)^(+0.7) kpc from Earth in the directions of M5,M13 and M15,respectively.This means M5's and M13's scattering screens are located at 3.0_(-0.2)^(+0.1) and 4.4_(-0.1)^(+0.1) kpc above the galactic plane,whereas,M15's is at 0.6_(-0.5)^(+0.3) kpc below the plane.We estimate the scintillation timescale and decorrelation bandwidth for each pulsar at each epoch using the one-dimensional auto-correlation in frequency and time of the dynamic spectra.We found that the boundary of the Local Bubble may have caused the scattering of M15,and detected the most distant off-plane scattering screens to date through pulsar scintillation,which provides evidence for understanding the medium circulation in the Milky Way.

关键词： pulsars scintillation globular clusters

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Timing and Single-pulse Study of Pulsar J1909+0122 Discovered by CRAFTS

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Research in Astronomy and Astrophysics 2023年第8期23卷 319-331页

作者： Yutong Chen Pei Wang Di Li Erbil Gügercinoğlu Rushuang Zhao Lingqi Meng Jianping Yuan Jiarui Niu Weiwei Zhu Yi Feng Chenchen Miao Chenhui Niu Qingdong Wu Na Wang Shen Wang Xiaoyao Xie Mengyao Xue jumei yao Mao Yuan Shanping You Xuhong Yu Youling Yue Jie Zhang Junshuo Zhang Lei Zhang Yabiao Wang Zhenye Gan Yuxi Li Zhongyi Sun Chengjie Wang National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China Institute for Frontiers in Astronomy and Astrophysics Beijing Normal UniversityBeijing 102206China Research Center for Intelligent Computing Platforms Zhejiang LaboratoryHangzhou 311100China Guizhou Normal University Guiyang 550001China Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China College of Physical Science and Technology Central China Normal UniversityWuhan 430079China Fudan University Shanghai 200443China Qilu Normal University Jinan 250200China Tencent Youtu Lab Shanghai 200233China

We report the discovery of PSR J1909+0122 by the Five-hundred-meter Aperture Spherical Radio Telescope(FAST)as part of the Commensal Radio Astronomy FAST Survey.PSR J1909+0122 has a spin period of 1.257 s and a dispersion measure of 186.2 pc cm^(-3).The averaged pulse profile shows two distinct components.We performed a single-pulse study based on a one-hour observation at 1.25 GHz on 2021 August 23.We used a threshold of 5σ_(ep) to measure the nulling fraction(NF)as 63%±1.5%.The longitude-resolved fluctuation spectra and fast Fourier transform spectra of the binary sequences revealed the quasi-periodicity of nulling with a period of 30 rotation periods.We examined the reliability of the periodicity by comparing it to random noise injection.The NF,E,and modulation periodicity P_(M) of PSR J1909+0122 were compared with other periodic nulling pulsars,showing that the source of J1909+0122 has the second largest NF in the population.Long-term timing observations over six months were used to derive the phase-connected ephemeris of this pulsar.The measured P and P values disfavor dipolar geometry for polar gap models,and the prediction for a space-charge-limited flow model in the case of inverse Compton scattering is only just above the death line.In this work,PSR J1909+0122 has revealed possible correlations between nulling behavior and pulsar properties,which will help to shed light on the pulsar emission mechanism and its temporal evolution in future observations.

关键词： (stars:)pulsars general-(stars:)pulsars individual(PSR J1909+0122)-stars neutron

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FAST discovery of an extremely radio-faint millisecond pulsar from the Fermi-LAT unassociated source 3FGL J0318.1+0252

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Science China(Physics,Mechanics & Astronomy) 2021年第12期64卷 10-17页

作者： Pei Wang Di Li Colin J.Clark Pablo M.Saz Parkinson Xian Hou Weiwei Zhu Lei Qian Youling Yue Zhichen Pan Zhijie Liu Xuhong Yu Shanping You Xiaoyao Xie Qijun Zhi Hui Zhang jumei yao Jun Yan Chengmin Zhang Kwok Lung Fan Paul S.Ray Matthew Kerr David A.Smith Peter F.Michelson Elizabeth C.Ferrara David J.Thompson Zhiqiang Shen Na Wang FAST&Fermi-LAT Collaboration CAS Key Laboratory of FAST National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China Jodrell Bank Centre for Astrophysics Department of Physics and AstronomyUniversity of ManchesterManchester M139PLUK Department of Physics and Laboratory for Space Research University of Hong KongHong Kong 999077China Santa Cruz Institute for Particle Physics University of CaliforniaSanta Cruz CA 95064USA Yunnan Observatories Chinese Academy of SciencesKunming 650216China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of SciencesKunming 650216China School of Computer Science and Technology Key Laboratory of Information and Computing Guizhou ProvinceGuizhou Normal UniversityGuiyang 550001China School of Physics and Electronic Science Guizhou Normal UniversityGuiyang 550001China Physics Department Stanford UniversityStanford CA 94305USA UMCP/CRESST/GSFC NASAGreenbeltMaryland MD 20771USA GSFC NASAGreenbeltMaryland MD 20771USA Centre d’´Etudes Nucl´eaires de Bordeaux Gradignan IN2P3/CNRSUniversit´e BordeauxGradignan 33175France Space Science Division U.S.Naval Research LaboratoryWashington DC 20375-5352USA Shanghai Astronomical Observatory Chinese Academy of SciencesShanghai 200030China Xinjiang Astronomical Observatory Urumqi 830011China Department of Physics University of MarylandCollege Park MD 20742USA NAOC-UKZN Computational Astrophysics Centre University of KwaZulu-NatalDurban 4000South Africa 不详

High sensitivity radio searches of unassociated γ-ray sources have proven to be an effective way of finding new pulsars. Using the Five-hundred-meter Aperture Spherical radio Telescope(FAST) during its commissioning phase, we have carried out a number of targeted deep searches of Fermi Large Area Telescope(LAT) γ-ray sources. On February 27, 2018 we discovered an isolated millisecond pulsar(MSP), PSR J0318+0253, coincident with the unassociated γ-ray source 3 FGL J0318.1+0252. PSR J0318+0253 has a spin period of 5.19 ms, a dispersion measure(DM) of 26 pc cm-3 corresponding to a DM distance of about 1.3 kpc, and a period-averaged flux density of(~11±2) μJy at L-band(1.05-1.45 GHz). Among all high energy MSPs, PSR J0318+0253 is the faintest ever detected in radio bands, by a factor of at least ~4 in terms of L-band fluxes. With the aid of the radio ephemeris, an analysis of 9.6 years of Fermi-LAT data revealed that PSR J0318+0253 also displays strong γ-ray pulsations. Follow-up observations carried out by both Arecibo and FAST suggest a likely spectral turn-over around 350 MHz. This is the first result from the collaboration between FAST and the Fermi-LAT teams as well as the first confirmed new MSP discovery by FAST, raising hopes for the detection of many more MSPs. Such discoveries will make a significant contribution to our understanding of the neutron star zoo while potentially contributing to the future detection of gravitational waves, via pulsar timing array(PTA) experiments.

关键词： FAST pulsar radio gamma rays

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脉冲星衍射式闪烁观测研究进展

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北京师范大学学报（自然科学版） 2020年第1期56卷 22-29页

作者：陶振钊王培姚菊枚朱炜玮支启军董爱军贵州师范大学物理与电子科学学院贵州贵阳550025 中国科学院国家天文台北京100101 贵州师范大学贵州省射电天文数据处理重点实验室贵州贵阳550025

介绍脉冲星星际闪烁效应产生的机制,简要描述衍射式闪烁的观测研究方法,并总结了近些年衍射式闪烁观测研究的进展,主要包含使用闪烁效应限制星际介质电子密度涨落谱、估算脉冲星切向速度、分辨脉冲星射电辐射区尺度、获取脉冲星双星轨... 详细信息

介绍脉冲星星际闪烁效应产生的机制,简要描述衍射式闪烁的观测研究方法,并总结了近些年衍射式闪烁观测研究的进展,主要包含使用闪烁效应限制星际介质电子密度涨落谱、估算脉冲星切向速度、分辨脉冲星射电辐射区尺度、获取脉冲星双星轨道参数、搜索脉冲星的非脉冲射电辐射等,以及总结了国内一些射电望远镜对脉冲星闪烁观测研究工作及FAST观测预期.

关键词：脉冲星星际介质散射闪烁

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抗防腐剂型微生物培养基研究

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微生物学通报 1999年第5期26卷 345-350页

作者：吴清平吴清平蔡芷荷张菊梅周小燕姚汝华华南理工大学广州510641 广东省微生物研究所广州510070

食品饮料中含有山梨酸、山梨酸钾、苯甲酸及苯甲酸钠等防腐剂会对其中的细菌和真菌的检出造成严重干扰，把测定体系的抗防腐剂指数控制在８１．１～９４．５之间，可较好地消除防腐剂对微生物生长的抑制。防腐剂解抑剂Ⅲ的抗防腐剂指数... 详细信息

食品饮料中含有山梨酸、山梨酸钾、苯甲酸及苯甲酸钠等防腐剂会对其中的细菌和真菌的检出造成严重干扰，把测定体系的抗防腐剂指数控制在８１．１～９４．５之间，可较好地消除防腐剂对微生物生长的抑制。防腐剂解抑剂Ⅲ的抗防腐剂指数为９２．３４，对细菌和真菌的生长无抑制作用，加入经改良和优化的普通培养基后，制得５种抗防腐剂型培养基，在灭菌前后和一年保存期内，它们的抗防腐剂指数基本保持不变。与普通培养基比较，当采用大样倾注平板法和液体大样法检测含有防腐剂的样品时，抗防腐剂型培养基可极大地提高样品中的细菌和真菌的检出率。

关键词：抗干扰微生物培养基防腐剂山梨酸苯甲酸

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原发性纵隔大B细胞淋巴瘤的诊治现状

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临床血液学杂志 2023年第3期36卷 215-218页

作者：程瑶施菊妹同济大学附属第十人民医院血液科上海200072 同济大学附属东方医院血液科

原发性纵隔大B细胞淋巴瘤是一种较为少见的血液系统恶性肿瘤,其诊断与治疗目前尚无统一的指南可供参考。近几年随着研究者更多的关注此疾病,其在诊断及治疗方面存在的困难及问题被一一指出;目前普遍认可的诊断方法为结合临床表现、形态... 详细信息

原发性纵隔大B细胞淋巴瘤是一种较为少见的血液系统恶性肿瘤,其诊断与治疗目前尚无统一的指南可供参考。近几年随着研究者更多的关注此疾病,其在诊断及治疗方面存在的困难及问题被一一指出;目前普遍认可的诊断方法为结合临床表现、形态学、免疫表型及影像学综合诊断;一线治疗多以免疫化疗方案联合/不联合巩固性放疗为首选,难治/复发性原发性纵隔大B细胞淋巴瘤的治疗则以靶向治疗和造血干细胞移植多见;但仍存在较多争议及问题有待解决。了解原发性纵隔大B细胞淋巴瘤的诊断及治疗对临床工作中减少漏诊及误诊具有重要意义。

关键词：原发性纵隔大B细胞淋巴瘤诊断治疗

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Tocilizumab in patients with moderate or severe COVID-19: a randomized, controlled, open-label, multicenter trial

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Frontiers of Medicine 2021年第3期15卷 486-494页

作者： Dongsheng Wang Binqing Fu Zhen Peng Dongliang Yang Mingfeng Han Min Li Yun Yang Tianjun Yang Liangye Sun Wei Li Wei Shi Xin yao Yan Ma Fei Xu Xiaojing Wang Jun Chen Daqing Xia Yubei Sun Lin Dong jumei Wang Xiaoyu Zhu Min Zhang Yonggang Zhou Aijun Pan Xiaowen Hu Xiaodong Mei Haiming Wei Xiaoling Xu Department of Pulmonary and Critical Care Medicine the First Affiliated Hospital of University of Science and Technology of China(Anhui Provincial Hospital)Hefei 230001China Division of Life Sciences and Medicine University of Science and Technology of ChinaHefei 230027China Intensive Care Unit the First Affiliated Hospital of University of Science and Technology of China(Anhui Provincial Hospital)Hefei 230001China Drug Clinical Trail Institution the First Affiliated Hospital of University of Science and Technology of China(Anhui Provincial Hospital)Division of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefei 230001China Department of Infectious Diseases Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430000China Department of Respiratory Medicine the Second People’s Hospital of FuyangFuyang 236000China Department of Respiratory Medicine National Key Clinical SpecialtyBranch of National Clinical Research Center for Respiratory DiseaseXiangya HospitalCentral South UniversityXiangya Lung Cancer CenterXiangya HospitalCentral South UniversityHunan Provincial Clinical Research Center for Respiratory DiseasesChangsha 410000China Lu’an People’s Hospital Affiliated to Anhui Medical University Lu’an 237005China Department of Pulmonary and Critical Care Medicine the First Affiliated Hospital of Bengbu Medical CollegeClinical Research Center for Respiratory Disease(tumor)in Anhui ProvinceBengbu 233004China Department of Respiratory Medicine Anqing Hospital Affiliated to Anhui Medical UniversityAnqing 246000China The First Affiliated Hospital of Nanjing Medical University Nanjing 210000China Department of Rheumatology and Immunology the First Affiliated Hospital of University of Science and Technology of China(Anhui Provincial Hospital)Hefei 230001China Department of Oncology the First Affiliated Hospital of University of Science and Technology of China(Anhui Provincial Hospital)Hefei 230001China Department of Endocrinology

Tocilizumab has been reported to attenuate the“cytokine storm”in COVID-19 patients.We attempted to verify the effectiveness and safety of tocilizumab therapy in COVID-19 and identify patients most likely to benefit from this treatment.We conducted a randomized,controlled,open-label multicenter trial among COVID-19 patients.The patients were randomly assigned in a 1:1 ratio to receive either tocilizumab in addition to standard care or standard care alone.The cure rate,changes of oxygen saturation and interference,and inflammation biomarkers were observed.Thirty-three patients were randomized to the tocilizumab group,and 32 patients to the control group.The cure rate in the tocilizumab group was higher than that in the control group,but the difference was not statistically significant(94.12%vs.87.10%,rate difference 95%CI−7.19%–21.23%,P=0.4133).The improvement in hypoxia for the tocilizumab group was higher from day 4 onward and statistically significant from day 12(P=0.0359).In moderate disease patients with bilateral pulmonary lesions,the hypoxia ameliorated earlier after tocilizumab treatment,and less patients(1/12,8.33%)needed an increase of inhaled oxygen concentration compared with the controls(4/6,66.67%;rate difference 95%CI−99.17%to−17.50%,P=0.0217).No severe adverse events occurred.More mild temporary adverse events were recorded in tocilizumab recipients(20/34,58.82%)than the controls(4/31,12.90%).Tocilizumab can improve hypoxia without unacceptable side effect profile and significant influences on the time virus load becomes negative.For patients with bilateral pulmonary lesions and elevated IL-6 levels,tocilizumab could be recommended to improve outcome.

关键词： tocilizumab coronavirus disease 2019(COVID-19) cytokine storm

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CDIO模式下连衣裙设计与制作课程教学实践研究

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鞋类工艺与设计 2023年第8期3卷 148-150页

作者：刘菊梅永州市工商职业中等专业学校湖南永州425000

为推进服装设计与工艺专业的中职职业教育改革,促进学生实践能力的全面发展,本文对前导课程进行数据分析,分析课程的教学现状,对接实际文创项目,在《连衣裙设计与制作》的课程中引入CDIO教学理念,以瑶族文化项目设计为切入点,通过“构... 详细信息

为推进服装设计与工艺专业的中职职业教育改革,促进学生实践能力的全面发展,本文对前导课程进行数据分析,分析课程的教学现状,对接实际文创项目,在《连衣裙设计与制作》的课程中引入CDIO教学理念,以瑶族文化项目设计为切入点,通过“构思―设计―实施―运行”实施CDIO教学模式;综合多种教学方法与信息化手段,融合多元化的评价方式,激发学生的学习动力,提高课程教学质量。

关键词：连衣裙设计与制作 CDIO模式文创项目教学实践

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木芙蓉茎皮果胶的提取及其对针织羊绒面料的应用

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毛纺科技 2016年第2期44卷 48-51页

作者：赵菊梅赵磊姚桂香盐城工业职业技术学院江苏盐城224000

研究从木芙蓉茎皮中提取天然植物果胶,将制得的果胶用于针织羊绒面料的整理,并研究面料整理前后的性能差异。结果表明:木芙蓉茎皮以酒石酸稀释液作为提取液,在p H值2,提取时间90 min,料液比1∶30工艺条件下,果胶得率可达13.24%,硫酸和... 详细信息

研究从木芙蓉茎皮中提取天然植物果胶,将制得的果胶用于针织羊绒面料的整理,并研究面料整理前后的性能差异。结果表明:木芙蓉茎皮以酒石酸稀释液作为提取液,在p H值2,提取时间90 min,料液比1∶30工艺条件下,果胶得率可达13.24%,硫酸和盐酸也可作为提取试剂,但果胶得率不如酒石酸。针织羊绒织物经木芙蓉果胶整理后,抗菌性能及防紫外性能得到显著提升,采用质量分数为7.5%木芙蓉果胶溶液整理后,面料对于波长小于290 nm的紫外光透过率趋于零,UPF值达到43,对金黄色葡萄球菌的抑菌率可达到94.571%

关键词：木芙蓉茎皮果胶针织羊绒织物整理防紫外抗菌性

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基于卫星遥感的洞庭湖水体面积变化及与水文的相关性

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中低纬山地气象 2022年第1期46卷 27-31页

作者：黄菊梅韩沁哲姚晟蒋帅黄海波湖南省岳阳市气象局湖南岳阳414000 气象防灾减灾湖南省重点实验室湖南长沙410118

该文利用2006-2020年洞庭湖水体遥感面积及水文资料,对洞庭湖水体面积变化特征及其与水文的相关性进行了探讨。结果表明洞庭湖水体面积离散程度较高且变幅大。岳阳市、益阳市、常德市水体面积分别占洞庭湖水体面积的68.62%、25.77%、5.... 详细信息

该文利用2006-2020年洞庭湖水体遥感面积及水文资料,对洞庭湖水体面积变化特征及其与水文的相关性进行了探讨。结果表明洞庭湖水体面积离散程度较高且变幅大。岳阳市、益阳市、常德市水体面积分别占洞庭湖水体面积的68.62%、25.77%、5.61%。其中位于岳阳市的岳阳县、湘阴县、位于益阳市的沅江市水体面积分别占洞庭湖水体面积的34.89%、17.35%、23.52%。占比越大的县市水体面积与洞庭湖水体面积相关性越大。洞庭湖水体面积与城陵矶水位的相关性高于常德、益阳水位。2010-2020年洞庭湖水体年最大面积显著增大。洞庭湖水体面积与城陵矶水位4阶多项式曲线拟合相关性最优。此外,不同的卫星/仪器、算法、分辨率以及天气条件对洞庭湖水体面积会产生一定的影响,洞庭湖区强降水对洞庭湖水体面积影响较大。

关键词：卫星遥感水体面积洞庭湖水位流量

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