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Low-latitude hydroclimate changes related to paleomagnetic variations during the Holocene in coastal southern China

Frontiers of Earth Science 2024年第2期18卷 324-335页

作者： Tingwei ZHANG Xiaoqiang YANG Jian YIN Qiong CHEN jianfang hu Lu WANG Mengshan JU Qiangqiang WANG School of Earth Science and Engineering/Guangdong Provincial Key Laboratory of Geodynamics and Geohazards/Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)Sun Yat-sen UniversityGuangzhou 510275China Institute of Cultural Heritage Shandong UniversityQingdao 266237China State Key Laboratory of Organic Geochemistry Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640China College of Urban and Environmental Sciences Peking UniversityBeijing 100871China Institute of Oceanology Chinese Academy of SciencesQingdao 266071China

The variations in precipitation have displayed a complex pattern in different regions since the *** formation processes may have a significant impact on precipitation,especially during the tropical marine processes and summer monsoon which convey abundant water vapor to coastal southern China and inland ***,we use two 7500 year sedimentary records from the Pearl River Delta and the closed Maar Lake,respectively,in coastal southern China to reconstruct the mid-to-late-Holocene humidity variability and explore its possible relationship with cloud cover modulated by the Earth’s magnetic fields(EMF).Our proxy records document an apparent increase in wetness in coastal southern China between 3.0 and 1.8 kyr *** apparent increase in humidity appears to be consistent with the lower virtual axial dipole moments and,in turn,with a lower *** correlation suggests that the EMF might have been superimposed on the weakened monsoon to regulate the mid-to-late-Holocene hydroclimate in coastal southern China through the medium of galactic cosmic rays,aerosols,and cloud ***,further investigations are needed to verify this interaction.

关键词： hydroclimate variations Earth’s magnetic field coastal southern China the Holocene epoch

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辽宁秀水盆地早白垩世义县组有机质富集机理研究——以LFD1井为例

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沉积学报 2024年第1期42卷 282-294页

作者：胡祖宏胡建芳席党鹏孙守亮陈树旺彭平安中国科学院广州地球化学研究所深地科学卓越创新中心有机地球化学国家重点实验室广州510640 中国科学院大学北京100049 中国地质大学(北京)生物地质与环境地质国家重点实验室北京100083 中国地质调查局沈阳地质调查中心沈阳110034

【目的】辽宁北部秀水盆地为中生代小型断陷盆地,发育沉积厚度巨大的下白垩统义县组地层,需要明确其有机质富集方式。【方法】通过对秀水盆地LFD1井义县组二段和三段沉积岩开展了有机质稳定碳同位素组成以及正构烷烃、甾烷和藿烷等生物... 详细信息

【目的】辽宁北部秀水盆地为中生代小型断陷盆地,发育沉积厚度巨大的下白垩统义县组地层,需要明确其有机质富集方式。【方法】通过对秀水盆地LFD1井义县组二段和三段沉积岩开展了有机质稳定碳同位素组成以及正构烷烃、甾烷和藿烷等生物标志化合物的有机地球化学研究。【结果与结论】秀水盆地LFD1井义县组二段和三段沉积岩有机质含量高,变化范围为0.01%~4.78%,且已经进入成熟阶段,具有良好的油气勘探前景;其有机质沉积演化划分为四个阶段:阶段Ⅰ,火山活动促进了生产力水平的提高,在弱还原—弱氧化的条件下形成了δ^(13)C_(org)偏轻、有机质含量高的沉积记录;阶段Ⅱ1,δ^(13)C_(org)偏重的陆生植物碎屑大量进入湖泊中,沉积环境处于强还原状态;阶段Ⅱ2,沉积环境在还原—弱氧化状态下变化,湖泊水体中藻类和水生植物繁盛,提供大量有机质促使形成了高TOC的沉积建造;阶段Ⅲ,沉积速率加快,对有机质富集起到了一定稀释作用,但该阶段的开始和结束出现了短暂的强还原沉积环境和水体分层,并在对应层位形成了有机质相对较高的沉积记录。

关键词：义县组生物标志化合物沉积环境有机质来源

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Spatiotemporal evolution of C3/C4 vegetation and its controlling factors in southern China since the last glacial maximum

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Science China Earth Sciences 2019年第8期62卷 1256-1268页

作者： Linlin CUI jianfang hu Xu WANG Institute of Geology and Geophysics Chinese Academy of SciencesBeijing100029China Key Laboratory of Cenozoic Geology and Environment Institute of Geology and GeophysicsChinese Academy of SciencesBeijing100029China Guanzhou Institute of Geochemistry Chinese Academy of SciencesBeijing510640China

To date, few research have been reported on the evolution of C3/C4 vegetation in southern China, and the main mechanism influencing the evolution of C3/C4 vegetation is unclear. That makes it difficult for researchers to understand the competition mechanism of C3 and C4 plants under different climate environments and its relationship with the climate factors. It is also not conducive for researchers to assess the influence of future climate change on regional C3/C4 vegetation. Exactly, C3/C4 vegetation change in the regional-scale will have a significant impact on the global carbon cycle and agricultural ***, it is especially important to reconstruct the evolutionary history of C3/C4 vegetation in southern China and clarify the influencing mechanism of climate change. In this study, we systematically analyzed stable carbon isotope(δ13 C) of the longchain n-alkanes in sediment samples from eight lakes and four peat profiles in southern China, to reconstruct the spatiotemporal evolution of C3/C4 vegetation in these regions since the Last Glacial Maximum(LGM) and to investigate the climate factors that affect the C4 plant abundance change in the research area. The integrated long-chain n-alkane(C27–C33) stable carbon isotope results of samples from Zhanjiang huguangyan Maar Lake, Xingyun Lake, Lugu Lake and Dingnan peat showed that, from the LGM to the Early Holocene, C4 plant relative abundance exhibited a gradually increasing trend from 21% to 34%. In the Middle Holocene, the C4 plant abundance significantly declined and reached a lowest value of 10%. In space, the C4 plant abundance generally exhibited a gradually declining trend from south to north in the LGM and the Early Holocene, while it showed an opposite trend in the Holocene Climate Optimum(6.0 cal ka BP). It reflected that the main influencing factor on C4 plants spatial distribution was changing from temperature to precipitation. This study indicated that temperature was the dominant facto

关键词： Stable carbon isotope Long-chain n-alkanes C3/C4vegetation Last Glacial Maximum Holocene Climate Optimum period

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华南地区典型食用鱼中4类卤代芳香化合物的污染特征和摄入风险

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生态毒理学报 2024年第3期19卷 259-273页

作者：张莉娜李会茹彭平安刘明洋胡建芳中国科学院广州地球化学研究所有机地球化学国家重点实验室&广东环境保护与资源利用重点实验室广州510640 华南师范大学环境学院/环境研究院广东省化学品污染与环境安全重点实验室&环境理论化学教育部重点实验室广州510006 中国科学院大学北京100049 中国科学院深地科学卓越中心广州510640 粤港澳环境污染与控制联合实验室广州510640

卤代芳香类化合物(HACs)具有环境普遍存在性、持久性、生物富集性和各种毒性,其污染和风险因此受到广泛关注。本研究对华南地区5种常见鱼肉中4类典型HACs进行了分析,结果表明,鱼肉中多氯代二苯并二噁英/呋喃(PCDD/Fs)、类二噁英多氯联苯... 详细信息

卤代芳香类化合物(HACs)具有环境普遍存在性、持久性、生物富集性和各种毒性,其污染和风险因此受到广泛关注。本研究对华南地区5种常见鱼肉中4类典型HACs进行了分析,结果表明,鱼肉中多氯代二苯并二噁英/呋喃(PCDD/Fs)、类二噁英多氯联苯(DL-PCBs)、多溴代二苯并二噁英/呋喃(PBDD/Fs)和总二噁英类(dioxins)毒性当量(TEQ)的平均值±标准偏差(范围)分别为(0.0680±0.3230)pg·g^(-1)(0~2.21 pg·g^(-1))、(0.118±0.124)pg·g^(-1)(0.000451~0.528 pg·g^(-1))、(0.139±0.164)pg·g^(-1)(0.00882~0.917 pg·g^(-1))和(0.325±0.366)pg·g^(-1)(0.0409~2.30 pg·g^(-1))(以单位湿质量计),均低于欧盟规定的鱼肉中dioxins的TEQ限值;5种鱼中桂花鱼的总TEQ和摄入风险最高,其次是鳗鱼和鲶鱼,鲈鱼最低,但种类间并无显著差异。鱼肉中多溴联苯醚(PBDEs)的浓度(0.347±0.297)ng·g^(-1)(0.0191~1.40 ng·g^(-1))(以单位湿质量计)与国内外相比中等偏低,种类变化顺序为三文鱼>鳗鱼>鲈鱼>桂花鱼>鲶鱼。鱼肉中的PCDD/Fs以高氯代PCDDs为主,可能源于污染饲料和五氯酚/五氯酚钠的使用;DL-PCBs以PCB-118和PCB-105为主,主要源于其商业品和金属冶炼过程;PBDEs的来源包括其商业品和高溴PBDEs脱溴降解;PBDD/Fs以高溴PBDFs为主,其污染与PBDEs密切相关。华南地区居民通过膳食鱼肉摄入4类HACs的致癌和非致癌风险值分别为6.56×10-6~2.87×10-5和0.0314~0.114,其中儿童风险值高于青少年和成人。PBDD/Fs对总TEQ和摄入风险的贡献(平均45.6%)远高于其他HACs,其生物体污染和风险值得持续关注。

关键词：卤代芳香化合物持久性有机污染物二噁英/呋喃多氯联苯多溴联苯醚致癌风险

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Determination of linear alkylbenzenesulfonates in modern sediments from core Zhu-9 and its significance

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Chinese Science Bulletin 2000年第S1期45卷 80-85页

作者： jianfang hu Ping’an Peng Yushun Min Guoying Sheng Jiamo Fu Chinese Acad Sci Guangzhou Inst Geochem State Key Lab Organ Geochem Guangzhou 510640 Peoples R China

High performance liquid chromatography (HPLC) has the advantages of rapid analysis and high sensitivity. In the present study a suitable analytical condition has been established for HPLC, and the LAS in modern sediments from core Zhu-9 at the Pearl River mouth has been determined by HPLC. The concentrations of C12-LAS homologues are the highest. The sedimentation flux of C12-LAS was correlated with the average flow of the Xijiang and Beijiang rivers: the higher the flow rate, the larger the C12-LAS sedimentation flux. This shows that the more rapidly the river flows, the shorter the LAS will stay in freshwater, the less the extent of biodegradation, the larger the C12-LAS sedimentation flux in the core Zhu-9.

关键词： high performance liquid chromatography (HPLC) Pearl River mouth modern sediment linear alkylbenz- enesulfonates (LAS) sedimentation flux annual average flow.

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Branched glycerol dialkyl glycerol tetraethers and paleoenvironmental reconstruction in Zoigê peat sediments during the last 150 years

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Chinese Science Bulletin 2011年第23期56卷 2456-2463页

作者： ZHOU HaoDa hu jianfang MING LiLi PENG PingAn ZHANG Gan Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China Graduate University of Chinese Academy of Sciences Beijing 100049 China

Branched glycerol dialkyl glycerol tetraethers (GDGTs) were analyzed in peat samples taken from the Zoigê grassland, located on the eastern margin of the Qinghai-Tibetan Plateau. The mean annual air temperature (MAAT) and pH in the 210 Pb-dating peat core were reconstructed based on the cyclization of branched tetraethers (CBT) and methylation of branched tetraethers (MBT) indices for the last 150 years. The results showed that the MAAT and pH values involved three stages of variation over the last 150 years. The pH was stable and the MAAT decreased slowly by about 1°C from 1851 to 1927. The pH decreased rapidly by 0.6 and the MAAT decreased significantly by 2.5°C between 1927 and 1979. The pH and MAAT increased by 0.8 and 5°C, respectively, since the 1980s. The reconstructed temperatures correspond well to the mean winter temperatures reconstructed using tree-rings from the Jiuzhaigou Valley, situated at the boundary between the Qinghai-Tibetan Plateau and the Sichuan Basin. The estimated MAAT was similar to the temperatures reconstructed using tree-rings, indicating an increasing trend, as shown by local instrumental records from 1957 to 2001. These results provide further confidence in the application of proxies based on glycerol dialkyl glycerol tetraethers in peat records for continental paleoclimate reconstruction.

关键词：泥炭记录二烷基甘油精神古环境沉积物青藏高原东缘空气温度

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Reconstruction of surface ocean water pCO_(2(aq)) in Nansha area,the South China Sea during the last 30 ka

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Chinese Science Bulletin 2003年第2期48卷 199-203页

作者： hu jianfang JIA Guodong PENG Ping FANG Dianyong ZHAO Quanhong State Key Laboratory of Organic Geochemistry Guangzhou Institute of Gcochemistry. Chinese Academy of Sciences Guangzhou 510640 China Laboratory of Marine Geology Tongji University Shanghai 200092ChinaademyofSciencesGuangzhou 510640China

The reconstruction of pCO2 in the tropic ocean is one of the most important issues to understand global cli-matic changes. In this study, the high-resolution strati-graphic analysis of core 17962 was conducted, which is lo-cated in the southern South China Sea (SCS). The contents of sedimentary organic matter, the stable carbon isotopic composition of sedimentary organic matter, and the d 13C values of black carbon and terrigenous n-alkanes were de-termined. And the d 13Cwc value of carbon derived from aquatic was calculated. On the basis of d 13Corg-pCO2 equa-tion proposed by Popp et al. (1989), we estimated the pCO2 in the Nansha area, SCS, since the last glaciation using d 13Cwc instead of d 13Corg. The results show that the average pCO2 was estimated at 240 ppmV during the last glaciation, and at 320 ppmV in the Holocene. A comparison of surface sea pCO2 with the atmosphere CO2 recorded in the Vostok ice core, indicates that CO2 in surface water of the southern SCS could emit into atmosphere during the last 30 ka.

关键词：南海南沙地区表层海水古二氧化碳分压全新世 pCO2 重建晚冰河期热带海洋

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Use of brGDGTs in surface geochemical exploration for petroleum —A case study of oil and gas fields in the Jiyang depression

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Science China Earth Sciences 2014年第6期57卷 1605-1612页

作者： ZHOU HaoDa hu jianfang XIONG YongQiang LIANG QianYong State Key Laboratory of Organic Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Graduate University of Chinese Academy of Sciences Zhuhai Central Station of Marine Environmental Monitoring State Oceanic Administration

Branched glycerol dialkyl glycerol tetraethers(brGDGTs),likely produced by bacteria in soil and peat,are widely distributed,easily detected,newly adopted biomarker *** this study,brGDGTs were used to explore the relationship between the absolute abundance of brGDGTs and the distribution of oil and gas fields in the Duoshiqiao area of the Jiyang *** results showed that the concentrations at the Xiakou fault and in the oil and gas fields were obviously higher than those in the contrast *** clear relationship among the concentration of brGDGTs,the distribution of oil and gas fields,and the acidolysis hydrocarbon(ethane)indicates that the concentration effectively responds to hydrocarbon seeps from the oil and gas field *** may become some of the most important indicators in surface geochemical prospecting for oil and gas.

关键词： brGDGTs Jiyang depression surface seep geochemical exploration petroleum

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血清人绒毛膜促性腺激素联合纤维蛋白原对无症状稽留流产的预测价值

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中国性科学 2024年第8期33卷 78-81页

作者：张英敏郝培芹胡建芳朱晓琴扬州大学医学院附属淮安市妇幼保健院计划生育科江苏淮安223000 淮安市中医院妇产科江苏淮安223000 扬州大学医学院附属淮安市妇幼保健院妇产科江苏淮安223000

目的探讨血清β-人绒毛膜促性腺激素(β-hCG)联合纤维蛋白原(FIB)在预测无症状稽留流产(MA)中的价值。方法收集2020年2月至2023年2月就诊于扬州大学医学院附属淮安市妇幼保健院的70例无症状MA患者作为观察组,收集同期同一医院的50例正... 详细信息

目的探讨血清β-人绒毛膜促性腺激素(β-hCG)联合纤维蛋白原(FIB)在预测无症状稽留流产(MA)中的价值。方法收集2020年2月至2023年2月就诊于扬州大学医学院附属淮安市妇幼保健院的70例无症状MA患者作为观察组,收集同期同一医院的50例正常妊娠孕妇作为对照组。检测两组患者β-hCG、雌二醇(E_(2))、黄体酮和FIB水平。绘制受试者工作特征(ROC)曲线分析β-hCG、E_(2)、黄体酮和FIB预测MA的效能。采用Delong检验比较各指标的预测效能。结果与对照组相比,观察组FIB和β-hCG显著升高,E_(2)和黄体酮显著降低。ROC曲线显示,β-hCG、E_(2)、黄体酮和FIB均可预测MA,曲线下面积分别为0.832、0.759、0.757和0.869。四项指标联合预测MA的曲线下面积为0.949,优于单项指标。FIB与β-hCG呈正相关,与E_(2)、黄体酮呈负相关。结论无症状MA患者FIB和β-hCG升高,E_(2)和黄体酮降低。四项指标联合检测可提高MA的预测效能,有助于识别高危人群。

关键词：稽留流产人绒毛膜促性腺激素纤维蛋白原预测

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Vesicular drug delivery systems for oral absorption enhancement

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Chinese Chemical Letters 2024年第7期35卷 73-88页

作者： Linghui Zou Meng Cheng Kaili hu jianfang Feng Liangxing Tu Jiangxi University of Chinese Medicine Nanchang 330006China Guangxi University of Chinese Medicine Nanning 530200China Shanghai University of Traditional Chinese Medicine Shanghai 201203China

Oral administration is the most acceptable route of drug delivery at this stage due to its convenience,safety,and ***,drugs given orally are exposed to a complex gastrointestinal environment,causing a tremendous challenge for their successful absorption into the *** the past decades,researchers have developed various novel pharmaceutical technologies to improve oral absorption,among which the vesicular drug delivery system(like liposomes,niosomes and transfersomes)has received extensive ***,there have been several investigations confirming the improved effect of vesicular drug delivery systems on oral drug ***,the clinical translation of oral vesicular drug delivery systems has been less impressive than implied by the positive results,and few vesicular formulations for oral use have been marketed *** this background,this article provides an overview of the current applications and challenges associated with the vesicular delivery systems available for oral drug delivery,specifically liposomes,niosomes,transfersomes,chitosomes and *** composition,formation mechanism,drug delivery advantages and application cases of these carriers in oral drug delivery are *** possible mechanisms by which vesicular carriers enhance oral drug absorption are analyzed in terms of the in vivo process of oral ***,the challenges that oral vesicular carriers now face,such as safety,undefined in vivo fate,and scale-up production,are summarized,while possible strategies to deal with them are *** reviewing the aforementioned,it can facilitate a more comprehensive knowledge of vesicular systems that can be used for oral drug delivery,providing a theoretical basis and reference for the design of oral formulations.

关键词： Vesicular Oral Mechanism Drug delivery Liposome Niosomes Transfersomes Chitosomes Bilosomes

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