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High-resolution geochemistry records of climate changes since late-glacial from Dajiuhu peat in Shennongjia Mountains,Central China

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Chinese Science Bulletin 2008年第S1期53卷 28-41页

作者： MA ChunMei ZHU Cheng ZHENG ChaoGui WU ChunLin GUAN Yong ZHAO ZhiPing HUANG LinYan HUANG Run School of Geographic and Oceanographic Sciences of Nanjing University Nanjing 210093China Department of Geography Chuzhou CollegeChuzhou 239012China

A peat core with depths of 297 cm was obtained from the Dajiuhu Basin(31°29′27″N,109°59′45″E,1760 m)in Hubei Province,Central China.10 AMS ages provide a time control and reveal that this core spans the past about 16.0 kaBP(calibrated age)(1 4C age:13.3 kaBP).Multi-proxy indexes analysis of geochemistry shows the following character of climate and environmental changes since about 16 kaBP:(1) The climate during the late-glacial period was cold and wet as a whole,but fluctuated continually.11.4- 12.6 ***,12.6-15.2 *** and 15.2-16 kaBP were corresponding respectively to the Younger Drays,Bφlling-Allerφd Warm Period and the Oldest Drays.(2)Inheriting the some climate characteristics of the late-glacial,the climate during the early-Holocene was wet and temperature increased gradually,during which an obvious dry event around 10.6 *** appeared.(3)The climate during the mid-Holocene was genarally warm and *** 9.2-7.5 kaBP,temperature increased gradually, precipitation was less comparatively and the 8.2 kaBP cold event which might be representative in the globe was reflected ***,multi-proxy records were relatively stable during 6.7-4.2 kaBP, which shows the best water and thermal condition in the Holocene Optimum.(4)Around 4.2 kaBP,the climate and environment transform from warm and wet to cool and dry,which may result in the collapse of the Neolithic Culture and midwifery the civilization of Xia Dynasty in this *** 0.9 kaBP,the climate turned cool and *** and environmental changes archived in Dajiuhu peat respond to the global changes since the late-glacial period and can be contrasted to the changes recorded in other high-resolution archives from the East Asia Monsoon region,which take on the variety model that the monsoon strengthened abruptly after the late-glacial,was strong during the early Holocene,subse- quently declined and became weak after the middle Holocene with dry *** to our analysis,the driving me

关键词： late-glacial Holocene Dajiuhu of Shenongjia peat climate changes geochemistry

On the Holocene sea-level highstand along the Yangtze Delta and Ningshao Plain,East China

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Chinese Science Bulletin 2003年第24期48卷 2672-2683页

作者： ZHUCheng ZHENGChaogui MAChunmei YANGXiaoxuan GAOXizhen WANGHaiming SHAOJiuhua DepartmentofUrbanandResourcesSciencesofNanjingUniversity Nanjing210093China DepartmentofChuzhouNormalCollege Chuzhou239012China ZhejiangInstituteofCulturalRelicsandArchaeology Hangzhou310014China HemuduSiteMuseumofZhejiang Yuyao315400China

The temporal-spatial distribution of Neolithicsites shows a long period of absence of human settlementsduring the early Holocene on the Yangtze Delta, and the area has not been colonized until 7000 aBP, corresponding to the onset of the Majiabang culture. Besides the regions east to the sandbar of Maqiao Site in Shanghai, foraminifera are not found in Neolithic cultural layers since 7000 aBP, indicating a widespread transgression between 10000 and 7000 *** of radiocarbon-dated cultural relics, foraminifera and pollen records from the Hemudu Site suggests that the Hemudu culture emerged and developed during themid-Holocene Climatic Optimum. Therefore, the hypothesisof a mid-Holocene sea-level highstand along the YangtzeDelta and Ningshao Plain from 7000 to 5000 aBP is an open debate. New evidence from archaeological excavations andbio-stratigraphy suggests that, prior to 7000 aBP, a high sea level occurred along the Ningshao Plain. Subsequently, the sea level was lowered between 7000 and 5000 aBP, and the area suffered from frequent floods from 5000 to 3900 aBP.

关键词：全新统长江三角洲中国东部地区海平面

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荧光光谱法研究羟基自由基诱导的酪氨酸氧化

光谱学与光谱分析 2011年第7期31卷 1838-1841页

作者：孙艳辉王卫龙吴霖生贾小丽滁州学院化学与生命科学系安徽滁州239012

二酪氨酸是酪氨酸氧化的标志性产物。为研究影响羟基自由基诱导酪氨酸氧化的因素,采用同步荧光光谱结合二维相关技术研究羟基自由基诱导酪氨酸氧化的反应过程。结果表明:pH变化时,二酪氨酸的荧光峰位、峰强发生变化。在羟基自由基诱导... 详细信息

二酪氨酸是酪氨酸氧化的标志性产物。为研究影响羟基自由基诱导酪氨酸氧化的因素,采用同步荧光光谱结合二维相关技术研究羟基自由基诱导酪氨酸氧化的反应过程。结果表明:pH变化时,二酪氨酸的荧光峰位、峰强发生变化。在羟基自由基诱导酪氨酸氧化体系中,随着酪氨酸浓度的增加,二酪氨酸产量升高;随着过氧化氢浓度的增加,二酪氨酸产量降低;酸性条件下,该反应易于发生,碱性条件下该反应难以发生;随着反应的进行,二酪氨酸荧光强度先增加后减小。二维同步荧光光谱相关分析表明,292 nm处荧光强度的变化快于281,300和374 nm处荧光强度的变化。因此,荧光光谱法研究羟基自由基诱导酪氨酸氧化,简单可行。

关键词：荧光光谱酪氨酸二酪氨酸羟基自由基二维相关光谱

3,4-吡啶二甲酸根钙配合物的合成、结构和性质(英文)

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无机化学学报 2011年第12期27卷 2489-2493页

作者：刘振锋吴刚郭莉李会会滁州学院化学与生命科学系滁州239012

配体3,4-吡啶二酸(H2pdc)和CaCO3反应合成了配合物[Ca2(pdc)2(H2O)7](1),用单晶X-射线、FTIR和元素分析对生成的晶体进行了表征。Ca(Ⅱ)采取八配位扭曲四方反棱柱几何构型,整个pdc2-作为三齿桥联配体连结3个不同的Ca(Ⅱ)原子形成一维链... 详细信息

配体3,4-吡啶二酸(H2pdc)和CaCO3反应合成了配合物[Ca2(pdc)2(H2O)7](1),用单晶X-射线、FTIR和元素分析对生成的晶体进行了表征。Ca(Ⅱ)采取八配位扭曲四方反棱柱几何构型,整个pdc2-作为三齿桥联配体连结3个不同的Ca(Ⅱ)原子形成一维链结构,一维链由π-π相互作用和O-H…N氢键连结形成二维层,二维层再进一步由O-H…O氢键连结形成三维结构。还研究了配合物1的荧光和热重性质。CCDC:806131。

关键词：钙配合物羧基荧光性质热重

Path Decomposition of Graphs with Given Path Length

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Acta Mathematicae Applicatae Sinica 2006年第4期22卷 633-638页

作者： Ming-qing Zhai Chang-hong Lü Department of Mathematics Chuzhou University Chuzhou 239012 China Department of Mathematics East China Normal University Shanghai 200062 China

A path decomposition of a graph G is a list of paths such that each edge appears in exactly one path in the list. G is said to admit a {Pl }-decomposition if G can be decomposed into some copies of Pl, where Pl is a path of length l - 1. Similarly, G is said to admit a {Pl, Pk}-decomposition if G can be decomposed into some copies of Pl or Pk. An k-cycle, denoted by Ck, is a cycle with k vertices. An odd tree is a tree of which all vertices have odd degree. In this paper, it is shown that a connected graph G admits a {P3, P4}-decomposition if and only if G is neither a 3-cycle nor an odd tree. This result includes the related result of Yan, Xu and Mutu. Moreover, two polynomial algorithms are given to find {P3}-decomposition and {P3, P4}-decomposition of graphs, respectively. Hence, {P3}-decomposition problem and {P3, P4}-decomposition problem of graphs are solved completely.

关键词： Algorithms graph path decomposition tree

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温度对金银花尺蠖存活和繁殖的影响

应用昆虫学报 2011年第2期48卷 364-369页

作者：向玉勇汪美英张元昶刘克忠殷培峰滁州学院化学与生命科学系滁州239012 滁州学院教务处滁州239012

在室内7个恒温(16、19、22、25、28、31和34℃)条件下研究了温度对金银花尺蠖Heterolocha jinyinhuaphaga Chu生长发育、存活、成虫寿命及繁殖等生物学特性的影响。结果表明,温度对其有显著的影响,金银花尺蠖各虫态的发育历期随温度升... 详细信息

在室内7个恒温(16、19、22、25、28、31和34℃)条件下研究了温度对金银花尺蠖Heterolocha jinyinhuaphaga Chu生长发育、存活、成虫寿命及繁殖等生物学特性的影响。结果表明,温度对其有显著的影响,金银花尺蠖各虫态的发育历期随温度升高而明显缩短,当温度继续升高到34℃,发育历期反而延长,各虫态发育历期同温度之间呈抛物线变化;25℃时金银花尺蠖各虫态的存活率最高,均达到90%以上,在高温和低温下,存活率则明显下降;低温条件下,金银花尺蠖的雌性比率大于雄性的比率,随着温度的升高,雌性比率在不断的下降;成虫寿命与温度成负相关,随着温度的升高而缩短;平均单雌产卵量在25℃时最高,为232.34粒,高温和低温下,则明显下降。

关键词：金银花尺蠖温度存活率成虫寿命性比产卵量

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利用同步荧光光谱快速鉴别潲水油

光谱学与光谱分析 2012年第10期32卷 2726-2729页

作者：孙艳辉安海洋贾小丽王娟滁州学院生物与食品工程学院安徽滁州239012

为快速鉴别潲水油,采用三维同步荧光光谱结合平行因子法解析潲水油的特征波长差(Δλ),并利用支持向量机建立潲水油鉴别模型。结果表明,潲水油的特征Δλ为60nm;特征Δλ下的样品原始同步荧光光谱经过主成分分析提取5个主成分,以径向基... 详细信息

为快速鉴别潲水油,采用三维同步荧光光谱结合平行因子法解析潲水油的特征波长差(Δλ),并利用支持向量机建立潲水油鉴别模型。结果表明,潲水油的特征Δλ为60nm;特征Δλ下的样品原始同步荧光光谱经过主成分分析提取5个主成分,以径向基函数(RBF)为核函数,利用网格搜索和6-fold交叉验证优化建模参数,得到惩罚因子C=512、核参数g=0.5,该条件下建立的模型对训练集和预测集的判别率均达到100%。采用同步荧光光谱可以快速、准确地鉴别潲水油。

关键词：潲水油同步荧光光谱平行因子法支持向量机鉴别

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高素质应用型人才培养路径研究

国家教育行政学院学报 2010年第6期 63-66页

作者：许志才滁州学院安徽滁州239012

高素质应用型人才是综合素质高,受过系统的专业实践技能训练,能将学到的专业知识和技能用在生产、建设、管理、服务岗位上的专门人才。建设高水平应用型本科院校有八个关键因素:坚持应用为本的办学定位;坚持设置应用性学科专业等。培养... 详细信息

高素质应用型人才是综合素质高,受过系统的专业实践技能训练,能将学到的专业知识和技能用在生产、建设、管理、服务岗位上的专门人才。建设高水平应用型本科院校有八个关键因素:坚持应用为本的办学定位;坚持设置应用性学科专业等。培养高素质应用型人才有八个关键环节:制定培养目标;明确培养规格;确定人才培养模式等环节。

关键词：应用型人才高素质应用型人才人才培养关键要素

THE LEAST SQUARES ESTIMATOR FOR AN ORNSTEIN-UHLENBECK PROCESS DRIVEN BY A HERMITE PROCESS WITH A PERIODIC MEAN

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Acta Mathematica Scientia 2021年第2期41卷 517-534页

作者： Guangjun SHEN Qian YU Zheng TANG Department of Mathematics Anhui Normal UniversityWuhu 241000China School of Statistics East China Normal UniversityShanghai 200062China School of Mathematics and Finance Chuzhou UniverstyChuzhou 239012China

We consider the least square estimator for the parameters of Ornstein-Uhlenbeck processes dY_(s)=(∑_(j=1)^(k)μ_(j)φ_(j)(s)-βY_(s))ds+dZ_(s)^(q,H),driven by the Hermite process Z_(s)^(q,H)with order q≥1 and a Hurst index H∈(1/2,1),where the periodic functionsφ_(j)(s),,j=1,...,κare bounded,and the real numbersμ_(j),,j=1,...,κtogether withβ>0 are unknown *** establish the consistency of a least squares estimation and obtain the asymptotic behavior for the *** also introduce alternative estimators,which can be looked upon as an application of the least squares *** terms of the fractional Ornstein-Uhlenbeck processes with periodic mean,our work can be regarded as its non-Gaussian extension.

关键词： Least squares estimator consistency asymptotic distribution Ornstein-Uhlenbeck processes Hermite processes