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Acta Geologica Sinica(English Edition) 2018年第1期92卷 367-377页

作者： LIU Shushuang LIU Dianbing WANG Yongjin zhao kan College of Geography Science Nanjing Normal University

One-year-resolved and annually-counted stalagmite multi-proxies （j180, ~13C, and layer width） from Daoguan Cave, Guizhou Province revealed detailed variability regarding the Asian Summer Monsoon （ASM） and local humidity across Bond events （BE） in the PreboreaL During BEs 8 and 7, 1.5%o enrichments in jlSo values were generally consistent with high- to low-latitude climate changes. In detail, the decadal-scale minor j180 oscillations in BE8 were broadly less than the mean value, in contrast to the significant changes in local soil moisture derived from the j13C values and layer records. In the mid-BE7, jlSo variability was generally above the average level, and higher- amplitude variations were observed in the three proxy indicators. Wavelet analysis on the total jlSo time series and across the specific time windows of BEs 8 and 7 identified periodicities of about 130, 60, and 20-a, respectively. Exceptionally strong in BE7, the 60-a cycle, pervasively observed in instrumental studies, became prominent starting at 11.4 kaBP. Thus, glacial background conditions are important for suppressing the ASM intensity in BE8, while during BE7, tropical hydrological circulations were potentially actively involved. Consequently, climate internal oscillations, analogous to modern conditions, might have occurred in the distant past once the link between the tropical ocean and atmosphere was established as occurs today.

关键词： Daoguan Cave the Preboreal Bond Event ASM global changes

LAMINAR DEVELOPING FLOW IN THE ENTRANCE REGION OF ROTATING CURVED PIPES

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Journal of Hydrodynamics 2006年第4期18卷 418-423页

作者： MA Jian-feng SHEN Xin-rong ZHANG Ming-kan ZHANG Ben-zhao Department of Mechanics Zhejiang University Hangzhou 310027 China

Three-dimensional laminar flow in the entrance region of rotating curved pipes was investigated. The governing equations were written in an orthogonal curvilinear coordinate system and solved with a fully three-dimensional numerical method. The development of secondary flow, axial velocity, local and average friction factors for different cases of rotation were given and discussed in detail. The results show that rotation influences the flow structure and friction factor greatly and that the secondary flow is sink-type in the early stage of development and then turns to vortex structure. The average friction factor and the intensity of secondary flow have drastic decrease near the entrance. At some proper rotation, the average friction factor can be noticeably reduced.

关键词： developing flow secondary flow rotating curved pipe

A global analysis searching for neutrinos associated with black hole merger gravitational wave events

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Research in Astronomy and Astrophysics 2018年第11期18卷 11-16页

作者： Yu-Zi Yang Jia-Jie Ling Wei Wang zhao-kan Cheng School of Physics Sun Yat-sen University School of Science Harbin Institute of Technology

Several neutrino observatories have searched for coincident neutrino signals associated with gravitational waves induced by the merging of two black holes. No statistically significant neutrino signal in excess of the background level was observed. These experiments use different neutrino detection technologies and are sensitive to various neutrino types. A combined analysis was performed on the KamLAND, Super-Kamiokande and Borexino experimental data with a frequentist statistical approach to achieve a global picture of the associated neutrino fluence. Both monochromatic and Fermi-Dirac neutrino spectra were assumed in the calculation. The final results are consistent with null neutrino signals associated with the process of a binary black hole merger. The derived 90% confidence level upper limits on the fluence and luminosity of various neutrino types are presented for neutrino energy less than110 MeV.

关键词： gravitational wave black hole merger neutrino fluence global analysis

ENSO-Like Pacing of the Asian Summer Monsoon during the Early Holocene

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Journal of Meteorological Research 2020年第2期34卷 325-335页

作者： Xiaohua SHAO Tao WANG Yongjin WANG Hai CHENG kan zhao Xinggong KONG School of Geography Nanjing University of Information Science & TechnologyNanjing 210044China Public Meteorological Service Center of Anhui Province Hefei 230031China Key Laboratory of Virtual Geographic Environment Ministry of EducationNanjing Normal UniversityNanjing 210023China Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application Nanjing 210023China Institute of Global Environmental Change Xi’an Jiaotong UniversityXi’an 710049China Department of Geology and Geophysics University of MinnesotaMN 55455USA

We present a230Th-dated stalagmite oxygen isotope(δ^18O)record from Loushanguan Cave in the Yangtze River valley,***^δ18O record,if viewed as a proxy of the Asian summer monsoon(ASM)intensity,provides an ASM history for the early Holocene with clear centennial-scale variability.A significant approximately 200-yr cycle between 10.2 and 9.1 ka BP(before present,where"present"is defined as the year AD 1950),as revealed by spectral power analyses,is of global significance and is probably forced by the Suess or de Vries cycle of solar ***,we explore a physical mechanism to explain the relationship between the solar activity and the ASM.A strong coherence between the ASM and El Ni?o–Southern Oscillation(ENSO)has been observed by performing crosswavelet analyses on this *** study suggests that a strong(weak)ASM state corresponds to a warm(cold)ENSO,which is consistent with modern meteorological observations but contrasts with previous studies on regions far from the Meiyu *** argue that the centennial fluctuations of the ASM are a fundamental characteristic forced by the solar activity,with the ENSO variability as a *** relationship between ENSO and the ASM displayed spatial heterogeneity on the centennial scale during the early Holocene,which is a more direct analogue to the observed modern interannual variability of the ASM.

关键词： isotope records Asian summer monsoon El Nino-Southern Oscillation centennial scale solar activity Yangtze River valley early Holocene

Superconducting properties of “111” type LiFeAs iron arsenide single crystals

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Science China(Physics,Mechanics & Astronomy) 2010年第7期53卷 1199-1201页

作者： XianCheng Wang QingQing Liu YuXi Lv Zheng Deng kan zhao RiCheng Yu JinLong Zhu ChangQing Jin Chinese Acad Sci Inst Phys Beijing 100190 Peoples R China

LiFeAs single crystal has been grown with superconducting transition temperature Tc comparable to that of polycrystals.A magnetic transition is found at about 160 K,which suggests the correlation of superconductivity ... 详细信息

关键词： iron based superconductor LiFeAs magnetic order

Ferromagnetism at 230 K in(Ba_(0.7)K_(0.3))(Zn_(0.85)Mn_(0.15))_2As_2 diluted magnetic semiconductor

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Chinese Science Bulletin 2014年第21期59卷 2524-2527页

作者： kan zhao Bijuan Chen Guoqiang zhao Zhen Yuan Qingqing Liu Zheng Deng Jinlong Zhu Changqing Jin Beijing National Laboratory for Condensed Matter Physics and Institute of PhysicsChinese Academy of Sciences

We report the ferromagnetism with Cure temperature Tcat 230 K in a new diluted magnetic semiconductor(DMS)(Ba0.7K0.3)(Zn0.85Mn0.15)2As2isostructural to ferropnictide 122 superconductors synthesized via low temperature *** is doped by isovalence substitution of Mn2+for Zn2+,while charge is introduced by heterovalence substitution of K1+for Ba2+in(Ba0.7K0.3)(Zn0.85Mn0.15)2As2DMS,being different from(Ga,Mn)As where both spin&charge are induced simultaneously by heterovalence substation of Mn2+for Ga3+.The(Ba0.7K0.3)(Zn0.85Mn0.15)2As2DMS shows spontaneous magnetization following T3/2dependence expected for a homogeneous ferromagnet with saturation moment 1.0μB for each Mn atom.

关键词：稀磁半导体铁磁性 DMS ZnO 固化温度烧结合成自发磁化饱和磁矩

Summer Monsoon Rainfall Variability in Central China over the Past 4700 Years and Its Possible Link to Solar Activity

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Journal of Meteorological Research 2021年第4期35卷 594-606页

作者： Jingwei ZHANG kan zhao Xinggong KONG Yongjin WANG Xianfang WANG Shushuang LIU Zhenjun WANG Hai CHENG R.Lawrence EDWARDS School of Geography and Environment Jiangxi Normal UniversityNanchang 330022China School of Geography Science Nanjing Normal UniversityNanjing 210023China Key Laboratory ofPoyang LakeWetland and Watershed Research of Ministry of Education Jiangxi Normal UniversityNanchang 330022China Lanling NO.4 Middle School Linyi 277700China Institute of Global Environmental Change Xi'an Jiaotong UniversityXi'an 710049China Department of Geology and Geophysics University of MinnesotaMinneapolis MN55455USA

Based on 467 pairs ofδ^(18)O andδ^(13)C records and 8230 Th dates from a stalagmite(BF4)from Xiniu Cave,central China,we present a reconstruction of 9-yr resolution monsoon rainfall record for the past 4700 ***δ^(18)O record shows good coherence with East Asian summer monsoon(EASM)rainfall proxies from adjacent regions during the overlapping intervals,suggesting thatδ^(18)O signal in BF4 can be interpreted as a monsoon rainfall ***δ^(13) C variations are related to changes in local processes at the cave site,and regional rainfall and temperature *** on theδ18 O record,a series of dry periods can be identified at 4500-4200,3500-3200,2800-2500,1900-1600,1400-1200,700-500,and 400-200 yr BP,while a series of wet periods can be identified at 4200-3600,2400-2200,3200-2800,1100-900,600-400,and 200-100 yr *** spectrum analysis on ourδ^(18) O record reveals significant cycles at 470 and 80 yr,coinciding with the typical solar periodic *** result suggests that changes in solar activity play a dominant role in driving centennial-decadal monsoon rainfall variation in central *** to minor changes in solar irradiance(less than 1.5 W m^(-2))over the past 4700 years,our record was further compared to the El Nino-Southern Oscillation(ENSO)and Pacific Decadal Oscillation(PDO)proxies,confirming that solar forcing on monsoon rainfall changes might be amplified by the ENSO and PDO *** 600 to 150 yr BP(the Little Ice Age,LIA),a positive shift of 2‰can be revealed in both theδ^(18)O andδ^(13)C records,indicating a cold/dry climatic *** comparing ourδ^(18)O andδ^(13)C records with historical documents,we suggest that the climatic deteriorations between 450 and 250 yr BP may have caused serious social unrest at the end of the Ming Dynasty.

关键词： stalagmite record Xiniu Cave solar activity El Nino-Southern Oscillation(ENSO) Pacific Decadal Oscillation(PDO) amplify mechanism Little Ice Age(LIA)

Ice-volume and insolation influences on hydroclimate changes in central eastern China during the antepenultimate glacial period

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Science China Earth Sciences 2023年第1期66卷 71-79页

作者： Quan WANG Shayue YUAN Yijia LIANG kan zhao Qingfeng SHAO Zhenqiu ZHANG Junji ZHU Xinggong KONG Yongjin WANG Jianghu LAN Hai CHENG Chengwei XIA Yi LI School of Geography and Tourism Chongqing Normal UniversityChongqing 401331China Chongqing Key Laboratory of Wetland Science Research of the Upper Reaches of the Yangtze River Chongqing 401331China School of Geographical Science Nantong UniversityNantong 226007China Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application School of GeographyNanjing Normal UniversityNanjing 210023China State Key Laboratory of Loess and Quaternary Geology Institute of Earth EnvironmentChinese Academy of SciencesXi’an 710061China Institute of Global Environmental Change Xi’an Jiaotong UniversityXi’an 710054China

The rainfall changes in East Asian summer monsoon(EASM)regions on the orbital timescale remain controversial due to the lack of reliable rainfall ***,we present new multiproxy records(δ^(18)O,δ^(13)C,Sr/Ca and Mg/Ca)of a230Thdated stalagmite from Hulu Cave in central eastern *** records reconstruct a regional hydroclimate history from 340 to 261 kyr BP(thousand years before present),approximately covering the antepenultimate glacial ***δ^(18)O record is dominated by the precessional cycles,suggesting that EASM responds to changes in Northern Hemisphere summer insolation(NHSI)on the orbital *** correlations amongst theδ^(13)C,Sr/Ca and Mg/Ca suggest that a common factor,i.e.,the local hydrological cycle,controlled their variability,and their leading principal component can be used as a proxy linked to regional *** composite record bears a good similarity to those from the Chinese Loess Plateau,showing a gradually decreasing rainfall during the antepenultimate glacial period,consistent with changes in global ice *** on the long-term trend,three relative wetter intervals were responding to the higher NHSI periods,suggesting that EASM rainfall variability was induced by integrated effects of global ice volume and *** increased ice sheets and lower NHSI resulted in an increased meridional temperature gradient and southward shift of the westerlies,which shortened the duration of Meiyu and midsummer *** differences between the rainfall record and the stalagmiteδ^(18)O record indicate that the latter represents the overall EASM intensity linked to monsoon circulation,but does not directly reflect the rainfall changes at the cave sites.

关键词： Hulu Cave Stalagmite records Antepenultimate glacial period East Asian summer monsoon rainfall

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Diluted ferromagnetic semiconductor(LaCa)(ZnMn)SbO isostructural to “1111” type iron pnictide superconductors

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Science China(Physics,Mechanics & Astronomy) 2013年第11期56卷 2026-2030页

作者： HAN Wei zhao kan WANG XianCheng LIU QingQing NING FanLong DENG Zheng LIU Ying ZHU JinLong DING Cui MAN HuiYuan JIN ChangQing National Lab for Condensed Matter Physics Institute of PhysicsChinese Academy of Sciences Department of Physics Zhejiang University

We report discovery of ferromagnetism in(LaCa)(ZnMn)SbO isostructural to the well-studied iron-based superconductor LaFeAs(O1 xFx).Spin is induced by partial substitution of Mn2+for Zn2+,while charge is induced by substitution of Ca2+for La3+within the parent compound *** with Curie temperature(TC)is observed up to 40 K at the spin doping 0.15 by introducing Mn2+into the Zn2+sites for(La0.95Ca0.05)(Zn1 xMnx)*** Hall coefficient measurement indicates p-type carrier for(La0.95Ca0.05)(Zn0.9Mn0.1)SbO with concentration of n^1020cm 3showing anomalous Hall effect below TC.

关键词： semiconductor "1111" type structure diluted magnetism

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我国斜视显微手术的探索

中华眼科杂志 2011年第11期47卷 961-963页

作者：赵堪兴天津医科大学眼科临床学院天津市眼科医院天津市眼科研究所天津市眼科学与视觉科学重点实验室 300020

随着手术显微镜引进眼科手术，开启了眼科显微手术时代，开创了现代白内障手术和玻璃体手术新纪元。当眼科显微手术时代走过了半个世纪后，国际上还是倡导戴2—3倍放大镜做斜视手术。显微手术仅仅是内眼手术的专利吗？我国斜视显微手术... 详细信息

随着手术显微镜引进眼科手术，开启了眼科显微手术时代，开创了现代白内障手术和玻璃体手术新纪元。当眼科显微手术时代走过了半个世纪后，国际上还是倡导戴2—3倍放大镜做斜视手术。显微手术仅仅是内眼手术的专利吗？我国斜视显微手术的最早报告见于20世纪90年代初，探索在显微镜下实施直肌睫状血管分离术，其后未见跟进。本世纪以来，一些日常做内眼显微手术的专家和一些显微手术训练基础好的青年骨干坚持探索斜视显微手术。在这个过程中，中华医学会斜视与小儿眼科学组积极引导探索其健康发展，努力发掘显微手术在斜视矫正术中的积极意义，并探索提高手术质量。2011年6月在济南召开的第14届全国斜视与小儿眼科学术会议对这一问题又进行了热烈交流和讨论。本文结合发展现状，总结了斜视显微手术的目的和意义，提出了健康发展斜视显微手术的措施与建议。

关键词：斜视显微手术