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Intermediate-mass black holes in Green pea galaxies(IMBH-GP)I:A candidate sample from LAMOST and SDSS

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Science China(Physics,Mechanics & Astronomy) 2024年第10期67卷 147-161页

作者： Ruqiu Lin Zhen-Ya Zheng Fang-Ting Yuan Jun-Xian Wang chunyan jiang Ning jiang Lingzhi Wang Linhua jiang Xiang Ji Shuairu Zhu Xiaodan Fu Key Laboratory for Research in Galaxies and Cosmology Shanghai Astronomical ObservatoryChinese Academy of SciencesShanghai 200030China School of Astronomy and Space Sciences University of Chinese Academy of SciencesBeijing 100049China CAS Key Laboratory for Research in Galaxies and Cosmology Department of AstronomyUniversity of Science and Technology of ChinaHefei 230026China Chinese Academy of Sciences South America Center for Astronomy(CASSACA) National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China CAS Key Laboratory of Optical Astronomy National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China Kavli Institute for Astronomy and Astrophysics Peking UniversityBeijing 100871China Department of Astronomy School of PhysicsPeking UniversityBeijing 100871China

The scaling relation of central massive black holes(M_(BH)s)and their host galaxies is well-studied for supermassive BHs(SM_(BH)s,M_(BH)≥10^(6)M_(⊙)).However,this relation has large uncertainties in the mass range of the intermediate-mass BHs(IM_(BH)s,M_(BH)~10^(3)-10^(6)M_(⊙)).Since Green pea(GP)galaxies are luminous compact dwarf galaxies,which may be likely to host less massive SM_(BH)s or even IM_(BH)s,we systematically search for M_(BH)s in a large sample of 2190 GP galaxies at z<0.4,selected from LAMOST and SDSS spectroscopic ***,we report a newly discovered sample of 59 M_(BH) candidates with broad Hα*** sample has a median stellar mass of 108.83±0.11M_(⊙)and hosts M_(BH)s with single-epoch virial masses ranging from M_(BH)~10^(4.7)to 10^(8.5)M_(⊙)(median 105.85±0.64M_(⊙)).Among the 59 M_(BH) candidates,36 have black hole masses M_(BH)≤10^(6)M_(⊙)(IM_(BH) candidates),one of which even has M_(BH)■10^(5)M_(⊙).We find that the M_(BH)-M_(*)relation of our M_(BH) sample is consistent with the M_(BH)-M_(bulge)relation for SM_(BH)s,while is above the M_(BH)-M_(*)relation for M_(BH)s in dwarf galaxies in the same mass ***,we show that 25 M_(BH) candidates,including 4 IM_(BH) candidates,have additional evidence of black hole activities,assessed through various methods such as the broad-line width,BPT diagram,mid-infrared color,X-ray luminosity,and radio *** studies show that it is very promising to find IM_(BH)s in GP galaxies,and the BH sample so obtained enables us to probe the connection between the M_(BH)s and compact dwarf galaxies in the low-redshift Universe.

关键词： SMBHs IMBHs Green pea galaxies compact dwarf galaxies

Self-powered electrochromic devices with tunable infrared intensity

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Science Bulletin 2018年第12期63卷 795-801页

作者： jiangman sun xiong pu chunyan jiang Chunhua Du Mengmeng Liu Yang Zhang Zhitian Liu Junyi Zhai Weiguo Hu Zhong Lin Wang CAS Center for Excellence in Nanoscience.Beijing Key Laboratory of Micro-nano Energy and Sensor.Beijing Institute of Nanoenergy and Nanosystems Chinese Academy of Sciences.Beijing 100083.China School of Nanoscience and Technology.University of Chinese Academy of Sciences.Beijing 100049.China School of Materials Science and Engineering.Georgia Institute of Technology Atlanta.GA 30332-0245.USA Wuhan Institute of Technology Materials Science and Engineering.Wuhang 430205 China

Triboelectric nanogenerator （TENG） is an efficient way to convert ambient mechanical energy into electricity to power up portable electronics. In this work, a flexible inflared electrochromical device （IR-ECD） with stable performances was assembled with a TENG for building self-powered infrared detector with tunable intensity. As driven by TENG, the electrochromic device could be operated in the mid-lR region due to the reversible electrochromic reactions. An average infrared reflectance contrast of 46% was achieved in 8-14 μm regions and as well a clear thermal image change can be observed. This work indicates that the TENG-driven infrared electrochromical device has potential for use in self-powered camouflage and tbermal control.

关键词： Infrared electrochromical device Triboelectric nanogenerator Self-powered Flexible Thermal control

Evolution of the commercial blocks in ancient Beijing city from the street network perspective

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Journal of Geographical Sciences 2018年第6期28卷 845-868页

作者： WANG Fang HE Jing jiang chunyan LI Yixi Sino-German Joint Laboratory on Urbanization and Locality Research(UAL) College of Architecture and Landscape ArchitecturePeking UniversityBeijing 100871China Key Laboratory for Earth Surface Processes Ministry of EducationPeking UniversityBeijing 100871China College of Urban and Environmental Sciences Peking UniversityBeijing 100871China

The synergistic relationship between urban functions and street networks has al-ways been a focus in the field of urban research and *** the perspective of street networks,by adopting space syntax,this study analyzed the deep structural characteristics and potential evolution rules of commercial blocks attached to street networks in different periods,as well as the corresponding economic,political,and cultural characteristics of an-cient Beijing city over the past 800 *** combining these with changes in the street network,we further explained the function mechanism of layout and level adjustment in commercial blocks,and the influence of the street network on commercial blocks in the process of historical *** main conclusions included the following:(1)The urban centripetal-centrifugal siphon effect:the layout form,topological structure,and traffic mode changes in the street network had corresponding guidance for the layout and hierarchical system of commercial blocks,while the centripetal development of the street network could guide the agglomeration effect of commercial blocks,although centrifugal development caused commercial blocks to display outward evacuation.(2)Stage transformation from mu-tation node to smooth development:the layout of commercial blocks came to depend on the ability to cross the commuting flow center,which originally relied on the accessibility of transportation nodes as local *** in traffic modes mainly affected the adjust-ment of the first-level commercial blocks,which easily led to overall layout *** levels have an obvious positive hierarchical relation with the second-and third-level com-mercial blocks.(3)The adaptation of traditional commercial blocks to the needs of a modern city:affected by the different emerging times and unevenness of the original commercial foundation,commercial blocks have formed various developmental models that meet the needs of modernization,and reach a balance betw

关键词： commercial block street network urban spatial-temporal evolution space syntax ancient Beijing city

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星系并合与相互作用的数值模拟和观测统计

中国科学：物理学、力学、天文学 2017年第4期47卷 34-47页

作者：姜春艳中国科学院上海天文台上海200030

在等级成团的结构形成过程中,星系并合与相互作用是非常普遍的现象.在引力的作用下,进入主暗晕的卫星星系受到动力学摩擦的作用而落入暗晕中心与中央星系并合;星系团中的星系高速交汇给星系内部注入能量从而改变着星系的形态;来自星系... 详细信息

在等级成团的结构形成过程中,星系并合与相互作用是非常普遍的现象.在引力的作用下,进入主暗晕的卫星星系受到动力学摩擦的作用而落入暗晕中心与中央星系并合;星系团中的星系高速交汇给星系内部注入能量从而改变着星系的形态;来自星系团的引力场对其中的星系进行着潮汐剥离甚至将其打散.星系的并合与相互作用在星系的演化中起着重要的作用,不仅能改变星系的形态,对星系的恒星形成性质产生影响,而且与活动星系核的演化相关联.借助数值模拟的理论研究与观测研究的共同发展,促进了人们对这一领域的认识,尤其是星系的理论并合时标、观测到的星系并合统计量及演化、并合在大质量星系的质量和大小增长中的作用等.

关键词：星系并合相互作用

StRAP2.3, an ERF-Ⅶ transcription factor, directly activates StInvInh2 to enhance cold-induced sweetening resistance in potato

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Horticulture Research 2021年第1期8卷 1072-1081页

作者： Weiling Shi Yuhao Song Tiantian Liu Qiuqin Ma Wang Yin Yuchen Shen Tengfei Liu chunyan jiang Kai Zhang Dianqiu Lv Botao Song Jichun Wang Xun Liu Chongqing Key Laboratory of Biology and Genetic Breeding for Tuber and Root Crops College of Agronomy and BiotechnologySouthwest University400715 ChongqingPeople’s Republic of China Key Laboratory of Horticultural Plant Biology(HZAU) Ministry of EducationKey Laboratory of Potato Biology and BiotechnologyMinistry of Agriculture and Rural AffairsHuazhong Agricultural University430070 WuhanPeople’s Republic of China

Potato invertase inhibitor(StInvInh2)positively regulates cold-induced sweetening(CIS)resistance by inhibiting the activity of vacuolar *** distinct expression patterns of StInvInh2 have been thoroughly characterized in different potato genotypes,but the related CIS ability has not been *** understanding of the regulatory mechanisms that control StInvInh2 transcription is *** this study,we identified an ERF‐Ⅶ transcription factor,StRAP2.3,that directly regulates StInvInh2 to positively modulate CIS *** as a nuclear-localized transcriptional activator,StRAP2.3 directly binds the ACCGAC cis-element in the promoter region of StInvInh2,enabling promoter *** of StRAP2.3 in CIS-sensitive potato tubers induced StInvInh2 mRNA abundance and increased CIS *** contrast,silencing StRAP2.3 in CIS-resistant potato tubers repressed the expression of StInvInh2 and decreased CIS *** conclude that cold-responsive StInvInh2 is due to the binding of StRAP2.3 to the ACCGAC cis-element in the promoter region of ***,these findings indicate that StRAP2.3 directly regulates StInvInh2 to positively modulate CIS resistance,which may provide a strategy to improve the processing quality of potatoes.

关键词： resistance inhibiting thoroughly

Three-dimensional structure of a low salinity tongue in the southern Taiwan Strait observed in the summer of 2005

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Acta Oceanologica Sinica 2009年第4期28卷 1-7页

作者： HONG Huasheng ZHENG Quanan HU Jianyu CHEN Zhaozhang LI chunyan jiang Yuwu WAN Zhenwen State Key Laboratory of Marine Environmental Science College of Oceanography and Environmental Science Xiamen University Xiamen 361005 China Department of Atmospheric and Oceanic Science University of Maryland College Park MD 20742 USA Department of Oceanography and Coastal Sciences Coastal Sciences School of the Coast and Environment Louisiana State University Baton Rouge LA 70803 USA

Cruise observations with CTD （conductivity-temperature-depth） profiler were carried out in the southern Taiwan Strait in the summer of 2005. Using the cruise data, two-dimensional maps of salinity and temperature distributions at depths of 5, 10, 15, 20, and 30 m were generated. The maps show a low salinity tongue sandwiched by low temperature and high salinity waters on the shallow water side and high temperature and high salinity waters on the deep water side. The further analysis indicates that the low salinity water has a nature of river-diluted water. A possible source of the diluted water is the Zhujiang （Pearl） Estuary. Meanwhile, the summer monsoon is judged as a possible driving force for this northeastward jet-like current. The coastal upwelling and the South China Sea Warm Current confine the low salinity water to flow along the central line of the strait. Previous investigations and a numerical model are used to verify that the upstream of the low salinity current is the Zhujiang Estuary. Thus, the low salinity tongue is produced by four major elements： Zhujinag Estuary diluted water, monsoon wind driving, coastal upwelling and South China Sea Warm Current modifications.

关键词： Taiwan Strait low salinity tongue river diluted water cruise measurement

Preparation of two triflate precursors for O-(2-[^(18)F] fluoroethyl)-L-tyrosine used in positron emission tomography (PET)

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Science China Chemistry 2009年第12期52卷 2195-2199页

作者： LIU chunyan1,2 & jiang ShenDe1 1 School of Pharmaceutical Science and Technology,Tianjin University,Tianjin 300072,China 2 Department of Pharmacy,North China Coal Medical College,Tangshan 063000,China School of Pharmaceutical Science and Technology Tianjin University Tianjin China Department of Pharmacy North China Coal Medical College Tangshan China

Two novel triflate precursors for radiolabelling of L-tyrosine in positron emission tomography (PET) for tumor imaging,O-(2-trifluoromethanesulfonyloxyethyl)-N-(tert-butoxycarbonyl)-L-tyrosine methyl ester 9a and O-(2-trifluoromethanesulfonyloxyethyl)-N-(tert-butoxycarbonyl)-L-tyrosine tert-butyl ester 9b,are synthesized. The triflate agent,9a or 9b,is prepared by esterification of methanol or transesterification of tert-butyl acetate with L-tyrosine,protection of the amine group with di-tert-butyl dicarbonate,alkylation with chlorohydrin,and triflation with trifluoromethanesulfonic anhydride in four steps with overall yields of 30% and 15%,respectively.

关键词： positron emission tomography triflate L-tyrosine [18F]FET precursor PET imaging

高管团队要素对公司企业家精神的影响机制研究——基于长三角民营中小高科技企业的实证分析

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南开管理评论 2011年第3期14卷 72-84页

作者：蒋春燕南京大学商学院

公司企业家精神越来越多地被认为是企业在动荡不确定环境下取得竞争优势的重要因素。虽然很多学者认为高管团队对公司企业家精神有重要影响,但很少有实证研究针对高管团队哪些具体特征及这些特征如何影响公司企业家精神给出结果,在转型... 详细信息

公司企业家精神越来越多地被认为是企业在动荡不确定环境下取得竞争优势的重要因素。虽然很多学者认为高管团队对公司企业家精神有重要影响,但很少有实证研究针对高管团队哪些具体特征及这些特征如何影响公司企业家精神给出结果,在转型经济中类似研究更是缺乏。本文基于Hambrick高管团队五要素的框架,以长三角七个国家级高新技术开发区220家民营中小高科技企业为被试对象,对高管团队各要素以及要素组合对公司企业家精神的作用机制进行实证研究。结果表明,高管团队首席执行官变革型领导行为、高管团队冒险倾向、行为整合、长期激励报酬以及责任分散都对公司企业家精神有显著的促进作用;而且高管团队长期激励报酬还与冒险倾向和行为整合有交互作用。

关键词：高管团队公司企业家精神民营中小高科技企业

金龟子绿僵菌对黄曲条跳甲体内保护酶活性的影响

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植物保护 2022年第5期48卷 129-133,157页

作者：蒋春艳龙岩市农业科学研究所福建龙岩364000

为探索绿僵菌对黄曲条跳甲保护酶活性的影响,分别用浓度为1×10^(8)、2×10^(8)、4×10^(8)、8×10^(8)、1.6×10^(9)个/mL的金龟子绿僵菌CQMa421孢子悬浮液处理黄曲条跳甲成虫,对侵染后黄曲条跳甲体内超氧化物歧化酶(SOD)、过氧化物酶(... 详细信息

为探索绿僵菌对黄曲条跳甲保护酶活性的影响,分别用浓度为1×10^(8)、2×10^(8)、4×10^(8)、8×10^(8)、1.6×10^(9)个/mL的金龟子绿僵菌CQMa421孢子悬浮液处理黄曲条跳甲成虫,对侵染后黄曲条跳甲体内超氧化物歧化酶(SOD)、过氧化物酶(POD)和过氧化氢酶(CAT)活性进行了研究。结果表明:处理后120 h内,SOD活性先升高后降低,48 h时SOD活性达最高,分别为69.5、72.5、74.5、75.9、76.7 U/g,SOD活性与孢子悬浮液浓度呈正相关;各处理POD活性在处理后72 h时开始上升,96 h时活性最高,分别为1 020、1 066.67、1 240、1 086.67、1 166.67 U/g,分别为对照组的3.33、3.48、4.04、3.54倍和3.80倍,随后开始下降;CAT活性变化总体趋势为上升—下降—上升—下降;3种酶活性最后都恢复至对照组水平,各处理组最大值间差异显著,且显著高于对照组,表明3种保护酶在黄曲条跳甲抵御金龟子绿僵菌入侵过程中均做出了应激反应。

关键词：金龟子绿僵菌黄曲条跳甲超氧化物歧化酶过氧化物酶过氧化氢酶

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