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Temperature and Hf-O isotope correlations of young erupted zircons from Tengchong(SE Tibet):Assimilation fractional crystallization during monotonic cooling

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Geoscience Frontiers 2023年第1期14卷 402-414页

作者： Zipei Guo haibo zou State Key Laboratory of Continental Dynamics Department of GeologyNorthwest UniversityXi'an 710069China Department of Geosciences Auburn UniversityAuburnAL 36849USA

Young zircons from crystal-poor volcanic rocks provide the best samples for the investigations of pre-eruption magmatic processes and for testing a possible relationship between zircon Eu anomalies and crustal *** report trace element chemistry and Hf-O isotope compositions of young zircons from 3 Holocene volcanoes in the Tengchong volcanic field,SE Tibet,in order to provide insights into magma evolution processes and conditions for high-K calc-alkaline volcanic rocks in a post-collisional *** decreasing zircon Ti content and falling temperature,zircon Hf content and Yb/Sm increase whereas zircon Eu anomaly and Th/U decrease,indicating fractional crystallization of plagioclase and zircon during magma *** importantly,zircon Hf isotope ratio(sHf values)increases with decreasing zircon Ti content and falling temperature(T),suggesting gradually increasing incorporation of relatively high EHf juvenile materials in the crystallizing zircons during magma *** correlations between zirconε_(Hf)and zirconδ^(18)O also support open-system magma *** data suggest fractional crystallization of a magma with simultaneous contamination by highε_(Hf)and lowδ^(18)O juvenile(immature)crustal materials during monotonic cooling after zircon *** low-T,high-ε_(Hf)and low-δ^(18)O zircons may indicate the involvement of the early Cretaceous juvenile granitic country rocks during shallow magma *** Eu anomalies in zircons from young Tengchong lavas yield crustal thickness of 40.7±6.8 km,consistent with present crustal thickness(42.5 km)determined by geophysical methods.

关键词： Zircon trace element chemistry Zircon Hf-O isotopes Tengchong volcanoes Continental post-collisional lavas Crustal thickness

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Radar Quantitative Precipitation Estimation Based on the Gated Recurrent Unit Neural Network and Echo-Top Data

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Advances in Atmospheric Sciences 2023年第6期40卷 1043-1057页

作者： haibo zou Shanshan WU Miaoxia TIAN Key Laboratory of Poyang Lake Wetland and Watershed Research of Ministry of Education&School of Geography and Environmental Science Jiangxi Normal UniversityNanchang 330022China Meteorological Sciences Institute of Jiangxi Province Nanchang 330046China Key Laboratory of Natural Disaster Monitoring Early Warning and Assessment of Jiangxi ProvinceNanchang 330022China Jiangxi Climate Center Nanchang 330046China

The Gated Recurrent Unit(GRU) neural network has great potential in estimating and predicting a variable. In addition to radar reflectivity(Z), radar echo-top height(ET) is also a good indicator of rainfall rate(R). In this study, we propose a new method, GRU_Z-ET, by introducing Z and ET as two independent variables into the GRU neural network to conduct the quantitative single-polarization radar precipitation estimation. The performance of GRU_Z-ET is compared with that of the other three methods in three heavy rainfall cases in China during 2018, namely, the traditional Z-R relationship(Z=300R1.4), the optimal Z-R relationship(Z=79R1.68) and the GRU neural network with only Z as the independent input variable(GRU_Z). The results indicate that the GRU_Z-ET performs the best, while the traditional Z-R relationship performs the worst. The performances of the rest two methods are *** further evaluate the performance of the GRU_Z-ET, 200 rainfall events with 21882 total samples during May–July of 2018 are used for statistical analysis. Results demonstrate that the spatial correlation coefficients, threat scores and probability of detection between the observed and estimated precipitation are the largest for the GRU_Z-ET and the smallest for the traditional Z-R relationship, and the root mean square error is just the opposite. In addition, these statistics of GRU_Z are similar to those of optimal Z-R relationship. Thus, it can be concluded that the performance of the GRU_ZET is the best in the four methods for the quantitative precipitation estimation.

关键词： quantitative precipitation estimation Gated Recurrent Unit neural network Z-R relationship echo-top height

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Sensitivity of Lake-Effect Convection to the Lake Surface Temperature over Poyang Lake in China

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Journal of Meteorological Research 2022年第2期36卷 342-359页

作者： haibo zou Shanshan WU Jiusheng SHAN Key Laboratory of Poyang Lake Wetland and Watershed Research of Ministry of Education&School of Geography and Environmental Science Jiangxi Normal UniversityNanchang 330022 Meteorological Sciences Institute of Jiangxi Province Nanchang 330046 Key Laboratory of Natural Disaster Monitoring Early Warning and Assessment of Jiangxi ProvinceNanchang 330022 Jiangxi Climate Center Nanchang 330046

In this study, high-resolution weather research and forecasting(WRF) simulations are used to explore the sensitivity of lake-effect convection over Poyang Lake(PL) to the change of lake surface temperature(LST). A control experiment(CTR) with climate mean LST(303 K) is compared with six sensitivity experiments(CTR-1/2/3K and CTR+1/2/3K) in which the LSTs are set based on the mean LST difference of 6 K between the maximum and minimum. The results show that the CTR experiment reasonably reproduces the lake-effect convection, and the lake-effect convection in sensitivity experiments is significantly influenced by the LST. With the increase of LST, the initiation time of the lake-effect convection is advanced gradually, while the initiation location moves PL from its *** lake-effect convection strengthens(weakens) in the increase-temperature CTR+1/2/3K(decrease-temperature CTR-1/2/3K) experiments, but the lake-effect convection does not monotonically strengthen with the LST, for the strongest one occurring in the CTR+1K experiment. The corresponding diagnostic analysis shows that the upward sensible heat flux and latent heat flux over PL increase with the LST, resulting in the enhancement of the lake-land breeze and the enlargement of the convective available potential energy(CAPE). This is the main reason for the changes in the initiation time and location, as well as the intensity of lake-effect convection in different *** addition, the non-monotonous variation of the level of free convection, which is mainly induced by the non-monotonous variation of the lifting condensation level, is responsible for the non-monotonous variation of the lake-effect convection intensity with the LST.

关键词： Poyang Lake lake-effect convection lake breeze convective available potential energy(CAPE) level of free convection(LFC)

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Improved Algorithms for Removing Isolated Non-Meteorological Echoes and Ground Clutters in CINRAD

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Journal of Meteorological Research 2018年第4期32卷 584-597页

作者： haibo zou Shuwen ZHANG Xudong LIANG Xueting YI College of Atmosphere Sciences Lanzhou UniversityLanzhou 730000 State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081 Meteorological Disaster Emergency Warning Center of Jiangxi Province Nanchang 330046

Using China New Generation Weather Radar （CINRAD） level-Ⅱ data, the original algorithms for removing isol-ated non-meteorological echoes and ground clutters in radar data, which have been applied to Weather Surveillance Radar-1988 Doppler （WSR-88D） in the USA and Severe Weather Automatic Nowcast （SWAN） system in China, are modified and improved. To remove isolated non-meteorological echoes, the new algorithm introduces a constraint parameter （Po） to distinguish whether a window of 5 x 5 points is isolated as external echoes. A statistical analysis of 150 radar scans （5 cases, with each case comprising 30 scans） under three different echo types （small-scale convec-tion, typhoon, and large-scale synoptic system） shows that the constraint parameter Po ≤ 0.167 is suitable for remov- ing isolated non-meteorological echoes while preserving the edge of meteorological echoes. A new parameter, NDZ, which promotes the ability of the algorithm to identify the ground clutters appearing at two adjacent elevation angles, is constructed based on the vertical continuity of reflectivity. These improved algorithms are tested for four cases （three cases of isolated non-meteorological echoes and one case of ground clutters）. Based on the statistics of 232 volume scans of radar data （on a temporal resolution of 1 h） measured at Nanchang station from 0000 UTC 5 to 1600 UTC 14 March 2015, it is found that the improved algorithms not only eliminate most （over 95% under clear-sky conditions） of the isolated non-meteorological echoes and ground clutters （including those appearing at two adjacent elevation angles）, but also well preserve the structure of meteorological echoes （storms）.

关键词： radar isolated non-meteorological echoes ground clutter quality control

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Analysis of a Convective Storm Crossing Poyang Lake in China

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Journal of Meteorological Research 2020年第3期34卷 529-545页

作者： haibo zou Shuwen ZHANG Yanan LIU Weidong ZHANG Xixi YANG College of Atmosphere Sciences Lanzhou UniversityLanzhou 730000 Institute of Meteorological Sciences of Jiangxi Province Jiangxi Meteorological BureauNanchang 330046

A convective storm crossing Poyang Lake(PL)in China during 1200-1600 UTC on 13 May 2015 is *** results show that this storm occurs ahead of a 500-hPa trough with weak low-level temperature advection and a convectively stable layer between 925 and 850 hPa,and the tail of the storm is enhanced when its spearhead sweeps over PL after the *** to the heating and moistening of PL,the convectively stable layer over PL is destabilized;and instead,a deep(below 700 hPa)convectively unstable layer is ***,both the radiative cooling and the storm-induced cooling result in a rapid air(near-surface)and land temperature decrease in the surrounding ***,a large lake-land temperature difference(about 6℃)occurs,which is conducive to generating land-lake breeze and enhancing the convergence of the low-level ***,the PL-induced deep convectively unstable layer and the enhanced low-level convergence jointly strengthen the crossing *** further confirm this,two simulations(with or without PL)are conducted with the Weather Research and Forecast(WRF)*** simulation with PL successfully reproduces the evolution of the storm crossing PL,while the simulation without PL *** the simulation with PL,a highμse tongue at 850 hPa associated with the storm moves eastward and downward,and merges with the PL-induced lake boundary layer,forming a deep convectively unstable layer under 700 ***,in the simulation without PL,the stable layer constantly maintains under 900 *** addition,the 900-hPa wind difference between the simulations with and without PL shows a land-lake breeze circulation that strengths the convergence of the low-level wind.

关键词： Poyang Lake(PL) lake-enhanced precipitation lake–land breeze convective instability

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Algorithm of Vertical Profiles of Radar Echoes between Any Two Points Based on Webpage and Its Application

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Meteorological and Environmental Research 2020年第1期11卷 34-39页

作者： Lei LI haibo zou Zhiming HE Secretariat of Jiangxi Meteorological Society Nanchang 330096China Jiangxi Institute of Meteorological Science Nanchang 330096China

Based on the puzzle data of radar reflectivity in and around Jiangxi Province,the slope profile method and the polar coordinate method were used to display the vertical profiles of radar echoes between any two *** technical route of extracting radar echo profile data by the slope method was proposed and applied to the short-term early warning platform of Jiangxi Province.A thunderstorm weather process occurring from Dongxiang to Wannian on September 23,2018 was analyzed by radar echo *** present,the program has been applied to the short-term early warning platform of Jiangxi Province based on B/S *** automatic drawing and display of radar echo profiles of any two points is practical for forecasters to quickly and effectively track short-term strong convection weather.

关键词： Radar echo Vertical section Short-term early warning platform

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中国年轻火山岩铀钍(U-Th)非平衡研究进展

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岩石学报 2011年第10期27卷 2821-2826页

作者：邹海波樊祺诚美国奥本大学地质地理系中国地震局地质研究所北京100029

本文简述近些年中国年轻火山岩的铀钍非平衡研究进展。中国东部(五大连池,天池,镜泊湖,龙岗,大兴安岭,海南岛)的年轻火山岩都显示显著的230Th过剩,表明岩浆来源于含石榴子石的深部地幔,并且部分熔融速率低。其中五大连池主要来自深部(≥... 详细信息

本文简述近些年中国年轻火山岩的铀钍非平衡研究进展。中国东部(五大连池,天池,镜泊湖,龙岗,大兴安岭,海南岛)的年轻火山岩都显示显著的230Th过剩,表明岩浆来源于含石榴子石的深部地幔,并且部分熔融速率低。其中五大连池主要来自深部(≥75km)的岩石圈地幔,天池、镜泊湖、龙岗和大兴安岭岩浆主要来自软流圈地幔,而海南岛火山岩则显示下地慢特征。中国东部年轻火山岩中U-Th非平衡并没有显示俯冲的太平洋板块对年轻火山岩的物质贡献。我们近来发现年轻火山岩中含有锆石。长白山天池火山岩千年喷发的碱流岩中的锆石U-Th等时线年龄为7～10ka。腾冲马鞍山的锆石表面U-Th等时线年龄为55ka,而锆石内部年龄是90ka。锆石年龄可能表明,相对于腾冲马鞍山的小喷发,大喷发的长白山天池火山岩浆滞留年龄短。长白山天池火山的很短的滞留时间表明其存在危险性。

关键词：铀钍非平衡岩浆滞留时间年轻火山岩年轻锆石中国

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姜黄素后处理肢体缺血再灌注肾损伤模型大鼠基质金属蛋白酶9及基质金属蛋白酶组织抑制因子1平衡的变化

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中国组织工程研究 2019年第23期23卷 3643-3648页

作者：邹海波孙晓峰沈阳医学院附属中心医院麻醉科

背景:姜黄素预处理可减轻肢体缺血再灌注对肾脏的损伤,但姜黄素后处理是否对肾脏损伤有保护作用及其机制目前研究甚少。目的:探讨大鼠肢体缺血再灌注肾组织损伤时姜黄素后处理对基质金属蛋白酶9/基质金属蛋白酶组织抑制因子1平衡的影响... 详细信息

背景:姜黄素预处理可减轻肢体缺血再灌注对肾脏的损伤,但姜黄素后处理是否对肾脏损伤有保护作用及其机制目前研究甚少。目的:探讨大鼠肢体缺血再灌注肾组织损伤时姜黄素后处理对基质金属蛋白酶9/基质金属蛋白酶组织抑制因子1平衡的影响。方法:成年雄性SD大鼠80只由中国医科大学实验室中心提供。实验方案经沈阳医学院附属中心医院动物实验伦理委员会批准。采用随机数字表法,将80只SD大鼠分为4组(n=20):假手术组、缺血再灌注组、姜黄素后处理组和地塞米松组。除假手术组外,其余大鼠采用夹闭双侧股动脉4h,再灌注4h的方法制备肢体缺血再灌注模型。在大鼠肢体缺血后4h,姜黄素后处理组经腹腔注射姜黄素200mg/kg,地塞米松组经腹腔注射地塞米松1.5mg/kg,假手术组、缺血再灌注组以等量生理盐水替代。于再灌注4h后,经颈动脉采集血样,检测肌酐、尿素氮;麻醉下取大鼠肾脏组织检测丙二醛水平,苏木精-伊红染色检测病理变化和肾小管间质半定量评分(SSRT);应用Westen blot法和RT-PCR法分别测定基质金属蛋白酶9、基质金属蛋白酶组织抑制因子1蛋白和核因子κB p65 mRNA含量,计算基质金属蛋白酶9/基质金属蛋白酶组织抑制因子1比值;应用ELESA法检测肺组织肿瘤坏死因子α和白细胞介素1β等炎性因子的水平。结果与结论:①与假手术组比较,缺血再灌注组血浆肌酐、尿素氮和丙二醛均升高(P<0.05);肾苏木精-伊红染色示肾小管扩张,管腔内可见管型,刷状缘消失、肾间质炎症细胞浸润等病变;SSRT升高(P<0.05);基质金属蛋白酶9、基质金属蛋白酶9/基质金属蛋白酶组织抑制因子1比值和核因子κB p65 mRNA含量均升高(P<0.05);肿瘤坏死因子α和白细胞介素1β炎性因子释放增加(P<0.05);②与缺血再灌注组比较,姜黄素后处理组血浆肌酐、尿素氮和丙二醛降低(P<0.05);肾组织炎性细胞浸润数量减少,管型消失,偶可见肾小管扩张;SSRT降低(P<0.05);基质金属蛋白酶9蛋白、基质金属蛋白酶9/基质金属蛋白酶组织抑制因子1比值和NF-κB p65 mRNA含量降低(P<0.05);肿瘤坏死因子α和白细胞介素1β炎性因子释放降低(P<0.05);③与姜黄素后处理组与地塞米松组比较各指标差异无显著性意义;④结果表明,姜黄素后处理可减轻大鼠肢体缺血再灌注造成的肾损伤,其机制与降低组织基质金属蛋白酶9/基质金属蛋白酶组织抑制因子1比值有关。

关键词：姜黄素缺血再灌注姜黄素后处理肾基质金属蛋白酶9 基质金属蛋白组织抑制因子1 肢体缺血再灌注肾损伤模型

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依托咪酯后处理肢体缺血再灌注肺损伤模型大鼠Fas/Fasl通路的变化

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中国组织工程研究 2020年第32期24卷 5162-5167页

作者：邹海波孙晓峰沈阳医学院附属中心医院辽宁省沈阳市110000

背景:目前文献已证实依托咪酯预处理可减轻肢体缺血再灌注对远隔脏器造成的损伤,但依托咪酯后处理对肢体缺血再灌注对远隔脏器是否有保护作用及其机制,目前报道甚少。目的:观察依托咪酯后处理对肢体缺血再灌注肺损伤的影响。方法:将大... 详细信息

背景:目前文献已证实依托咪酯预处理可减轻肢体缺血再灌注对远隔脏器造成的损伤,但依托咪酯后处理对肢体缺血再灌注对远隔脏器是否有保护作用及其机制,目前报道甚少。目的:观察依托咪酯后处理对肢体缺血再灌注肺损伤的影响。方法:将大鼠采用夹闭双侧股动脉2 h、再灌注3 h的方法制备肢体缺血再灌注肺损伤模型,设为模型组;于大鼠肢体缺血2 h后,经尾静脉分别注射依托咪酯1.0 mg/kg或地塞米松0.2,0.5和1.0 mg/kg,分别设为依托咪酯后处理组、地塞米松0.2,0.5,1.0 mg/kg组。各组于再灌注3 h时经颈动脉取血,行动脉血气分析,记录血氧分压。随后取大鼠肺组织采用免疫组织化学染色检测病理变化、应用Hoechst33258染色法检测肺细胞凋亡指数以及检测肺湿/干质量比;应用WestenBlot法和RT-PCR法分别测定肺组织Fas蛋白和Fasl mRNA的表达;采用ELISA法测定肺组织肿瘤坏死因子α及白细胞介素1β水平。结果与结论:①与模型组比较,在依托咪酯后处理组中血氧分压升高(P0.05);③上述结果证实,依托咪酯后处理可降低大鼠肢体缺血再灌注导致的肺损伤,其机制可能与下调Fas/Fasl有关;在统计学角度上,依托咪酯1.0 mg/kg降低肺损伤的效价强度,几乎相当于地塞米松0.5 mg/kg。

关键词：依托咪酯后处理缺血再灌注肺 Fas Fasl 凋亡指数氧分压肿瘤坏死因子α 白细胞介素1β 大鼠

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中国东部全新世火山的镭-钍同位素年代学

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岩石学报 2020年第7期36卷 1945-1952页

作者：邹海波郭紫佩樊祺诚赵勇伟 Department of Geosciences Auburn UniversityAuburnAL 36830 大陆动力学国家重点实验室西北大学地质系西安710069 中国地震局地质研究所北京100029

活火山是指1万年来有过喷发历史的全新世火山。火山的高分辨年代学对火山灾害评估和火山分类具有重要意义。对于缺乏历史记载的全新世火山,直接对火山岩进行同位素定年很困难。本文利用具有高时间分辨率的镭-钍-铀非平衡确定中国东部年... 详细信息

活火山是指1万年来有过喷发历史的全新世火山。火山的高分辨年代学对火山灾害评估和火山分类具有重要意义。对于缺乏历史记载的全新世火山,直接对火山岩进行同位素定年很困难。本文利用具有高时间分辨率的镭-钍-铀非平衡确定中国东部年轻火山的年龄。根据镭-钍-铀同位素,海南岛的马鞍岭和雷虎岭是全新世火山(马鞍岭:4.3ka;雷虎岭:4.7ka);镜泊湖火山(4.9ka)也是全新世火山;龙岗火山存在晚更新世和全新世活动(7.0ka,15.0ka);大兴安岭阿尔山和诺敏河Ra/Th非平衡消失但230Th/238U非平衡显著,属于晚更新世喷发(阿尔山:63ka;诺敏河:71ka)。海南岛的马鞍岭火山、雷虎岭火山和东北地区的龙岗火山、镜泊湖火山,是4座活火山。至于东北地区的阿尔山和诺敏河火山是否是活火山,有待测试更多样品的Ra/Th同位素。五大连池老黑山和火烧山有历史喷发记录,这与它们都存在显著Ra/Th非平衡一致。五大连池老黑山和火烧山的岩浆滞留年龄分别小于4.2ka和3.2ka,岩浆上升速率>18~23m/y。

关键词：活火山全新世火山晚更新世火山铀系非平衡镭钍非平衡

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