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Rare Earth Element Geochemistry of Phosphatic Rocks in Neoproterozoic Ediacaran Doushantuo Formation in Hushan Section from the yangtze Gorges Area, South China

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Journal of Earth Science 2016年第2期27卷 204-210页

作者： Hong Xin Shaoyong Jiang jinghong yang Heping Wu Daohui Pi State Key Laboratory for Mineral Deposits Research Department of Earth Sciences Nanjing University State Key Laboratory of Geological Processes and Mineral Resources Collaborative Innovation Center for Exploration of Strategic Mineral Resources Faculty of Earth Resources China University of Geosciences

Phosphatic rocks are widely distributed in Neoproterozoic Ediacaran Doushantuo Formation in yangtze Gorges Area, South China. In this study, rare earth element geochemistry of eight phosphatic rock samples from the Hushan Section has been studied. All the samples display typical hat-shaped REE patterns, moderate negative Ce anomalies（Ce/Ce＊=0.55 to 0.67）, slightly positive Eu anomalies（Eu/Eu＊=1.05 to 1.22） and low Y/Ho ratios（38.2±5.6）. The hat-shaped REE patterns indicate diagenetic alteration of the primary REE signatures, which coincides with detrital siliciclastic sources of REE based on the Y/Ho ratios. The degree of Negative Ce anomalies and positive Eu anomalies may have recorded the redox features of diagenetic fluids, suggesting an anoxic environment during the phosphogenesis processes in Neoproterozoic Ediacaran Doushantuo Formation, South China. The geochemical comparison between the Lower Phosphorite Layer and Upper Phosphorite Layer at Hushan indicates a greater degree of diagenesis occurred in the Upper Layer than the Lower one. Besides the terrigenous sources of REE, organic materials could have also played a role on the REE characteristics.

关键词： phosphatic rocks rare earth element Ediacaran Doushantuo Formation yangtzeGorges area.

Trace Elements Characteristics of Black Shales from the Ediacaran Doushantuo Formation, Hubei Province, South China： Implications for Redox and Open vs. Restricted Basin Conditions

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Journal of Earth Science 2018年第2期29卷 342-352页

作者： Bi Zhu Shaoyong Jiang Daohui Pi Lu Ge jinghong yang Institute of Isotope Hydrology School of Earth Sciences and Engineering Hohai University Nanjing 210098 China State Key Laboratory of Geological Processes and Mineral Resources Faculty of Earth Resources Collaborative Innovation Center for Exploration of Strategic Mineral Resources China University of Geosciences Wuhan 430074 China State Key Laboratory for Mineral Deposits Research School of Earth Sciences and Engineering Nanjing University Nanjing 210093 China

In the present study, we carried out trace element analyses of black shales of the Edia- caran Doushantou Formation from two sections （Jiulongwan, Baiguoyuan） in Hubei Province, South China. Mo-U characteristics of black shales from the two sections and compiled Mo-U data of Dou- shantuo black shales from sections of a variety of sedimentary facies described the temporal/spatial variability in the redox conditions of paleo-seawater during deposition of the Donshantuo Formation. Changes in Mo-U patterns of the Doushantuo Member II （DST2） shales of open marine environments are consistent with a shift from a predominately oxic to a predominately anoxic ocean during their deposition. Mo-U patterns of the DST2 black shales from intra-shelf sections reflect basin restriction may have happened in the intra-shelf basin and are compatible with the redox-stratified model of the intra-shelf basin. Mo-U patterns of black shales of the Doushantuo Member IV （DST4） reveal that the shales from intra-shelf sections have more pronounced Mo enrichment and more significant enrich- ment of Mo over U than the slope shales, indicating the operation of a Mn particulate shuttle in the intra-shelf basin. High Mo/TOC ratios of the DST4 at the intra-shelf sections, in combination with similar Mo-TOC patterns of the DST4 from both intra-shelf and slope sections, indicate the intra- shelf basin was well connected to the open ocean during deposition of the DST4.

关键词： Doushantuo Formation Mo-U eovariation Mo/TOC South China.

Glycerol ether biomarkers and their carbon isotopic compositions in a cold seep carbonate chimney from the Shenhu area, northern South China Sea

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Chinese Science Bulletin 2011年第16期56卷 1700-1707页

作者： GE Lu JIANG ShaoYong yang Tao yang jinghong WU NengYou ZHANG GuangXue LIU Jian State Key Laboratory for Mineral Deposits Research and Center for Marine Geochemistry Research Department of Earth Sciences Nanjing University Nanjing 210093 China Guangzhou Marine Geologwal Survey Guangzhou 510760 China

At modern cold seeps,the anaerobic oxidation of methane(AOM)is the dominant pathway for methane consumption in marine ***,which is mediated by a consortium of methane oxidizing archaea and sulfate reducing bacteria,is proposed to be responsible for authigenic carbonate formation.A methane-derived carbonate chimney was collected from the Shenhu area, northern South China *** membrane lipids and their very low carbon isotopic compositions(?115‰to?104‰)in the Shenhu chimney suggest the presence of an AOM *** specific archaeal and bacterial biomarkers were detected,including Ar,DAGE 1f,and monocyclic *** strongly depleted??13C values(?115‰to?104‰),which are lower than those of the normal marine lipids in sediments,reveal biogenic methane as their *** carbonate deposits exhibiting a chimney structure indicate that a vigorous methane-rich fluid expulsion may have occurred at the *** propose that the decomposition of gas hydrates at depth is the likely cause of seepage and cold seep carbonate formation in the Shenhu area.

关键词：碳同位素组成生物标志物自生碳酸盐烟囱结构中国南海冷泉南海北部甘油醚

Geochemical characteristics of pore water in shallow sediments from Shenhu area of South China Sea and their significance for gas hydrate occurrence

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Chinese Science Bulletin 2010年第8期55卷 752-760页

作者： yang Tao JIANG ShaoYong GE Lu yang jinghong WU NengYou ZHANG GuangXue LIU Jian State Key Laboratory for Mineral Deposits Research Center for Marine Geochemistry Research Nanjing University Nanjing 210093 China Guangzhou Marine Geological Survey Guangzhou 510760 China

The Shenhu area is one of the promise target areas for marine gas hydrate exploration in the northern margin of the South China *** water samples were collected from two piston cores (8.75 and 8.52 m) in site HS-A and site HS-B in the Shenhu area,and their major anion and cation contents and trace element contents have been analyzed in this ***- concentrations in pore waters are similar to the seawater value and no systematic change along depth profiles has been found for the Cl- content in both *** site HS-A,the SO 2- 4 contents show a limited range in pore waters from 0 to 3 m depths,but a dramatic decrease is documented in depth below 3 *** elements such as Ca 2+,Mg 2+ and Sr 2+ show similar variation patterns as the SO 2- 4,i.e.,no variation in 0-3 m,but large decrease in depth below 3 *** site HS-B,both the SO 4 and Ca 2+,Mg 2+ and Sr 2+ display a decrease pattern along the depth profile,but in 0-3 m the variation is less significant than those in depth below 3 *** both sites HS-A and HS-B,I contents show a dramatic increase along depth *** show that the SMI depths are very shallow (10 and 11 m) in both sites,and the sulfate flux and I flux are very *** geochemical characteristics and anomalies at Shenhu are quite similar to those found in other gas hydrate locations in the world,and a genetic link is suggested to be related to the gas hydrate occurrence at depths in the study *** summary,we suggest that combined geochemical parameters in shallow sediment pore waters are useful indicators to indicate the gas hydrate occurrence at depths.

关键词：天然气水合物地球化学特征南中国海沉积物孔隙水浅层

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层状陶瓷与镍扩散连接接头微观组织及性能

焊接学报 2024年第9期45卷 103-109页

作者：杨景红刘甲坤魏文庆叶超超刘永胜张丽霞刘启明潍坊学院机械与自动化学院潍坊261061 潍坊市工业发展促进中心潍坊261041 哈尔滨工业大学先进焊接与连接国家重点实验室哈尔滨150001 中国机械总院集团哈尔滨焊接研究所有限公司哈尔滨150028

采用扩散连接方式对Ni与Ti_(3)AlC_(2)陶瓷进行连接,为了对Ni与Ti_(3)AlC_(2)的反应层进行详细分析,利用SEM、TEM对接头的微观组织进行研究,了解Ni扩散机制及接头形成机理.结果表明,在扩散连接过程中,Ni元素向原始Ti_(3)AlC_(2)陶瓷组... 详细信息

采用扩散连接方式对Ni与Ti_(3)AlC_(2)陶瓷进行连接,为了对Ni与Ti_(3)AlC_(2)的反应层进行详细分析,利用SEM、TEM对接头的微观组织进行研究,了解Ni扩散机制及接头形成机理.结果表明,在扩散连接过程中,Ni元素向原始Ti_(3)AlC_(2)陶瓷组织的扩散优先沿着晶界及相界面进行,在此处Ni会发生明显的富集,由于Ni与Ti_(3)AlC_(2)陶瓷有较好的化学相容性,因此两者之间能够发生化学反应形成扩散连接接头,随着保温时间的延长,Ni的扩散更加充分,因此形成较为连续的Ni的扩散层.在扩散连接温度为900℃,保温时间为60 min时,Ni与Ti_(3)AlC_(2)陶瓷扩散连接接头的典型界面组织为Ni/Ni_(3)(Al,Ti)+AlNi_(2)Ti+TiC/Ti_(3)AlC_(2)陶瓷,随着扩散连接温度升高,接头抗剪强度表现为先增后减,当扩散连接温度为900℃,保温时间60 min,Ni/Ti_(3)AlC_(2)陶瓷接头具有最优的力学性能,抗剪强度可达94.4 MPa.

关键词：扩散连接 Ti_(3)AlC_(2)陶瓷微观组织扩散连接温度抗剪强度

Bioadaptation of implants to In vitro and In vivo oxidative stress pathological conditions via nanotopography-induced FoxO1 signaling pathways to enhance Osteoimmunal regeneration

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Bioactive Materials 2021年第10期6卷 3164-3176页

作者： Jingyan Huang Ruoqi Li jinghong yang Min Cai Yichen Lee Anxun Wang Bin Cheng Yan Wang Hospital of Stomatology Guanghua School of StomatologySun Yat-sen University and Guangdong Key Laboratory of StomatologyGuangzhouGuangdong510055China Department of Oral and Maxillofacial Surgery The First Affiliated Hospital of Sun Yat-sen UniversityGuangzhouGuangdong510080China

Varieties of pathological conditions,including diabetes,are closely related to oxidative stress(OS),but the osseointegration or bioadaptation of implants to OS and the related mechanism remain poorly *** this study,the antioxidation and osteoimmune regeneration of titanium implants with micro/nanotopographies were evaluated under H2O2-,lipopolysaccharide(LPS)-and hyperglycemia-mediated cellular OS models and in diabetic rats as a representative animal model of ***2 nanotube(TNT)coating on titanium implants directly induced superior osteogenic differentiation of bone mesenchymal stem cells(MSCs)and osseointegration compared with microscale sand blasted-acid etched topography(SLA)under OS,attributed to higher superoxide dismutase 2 activity,the neutralization of intracellular reactive oxygen species(ROS),and less ***,the oxidation resistance on TNT is driven by upregulated forkhead box transcription factor O1(FoxO1),which is abolished after knockdown of FoxO1 via shRNA in ***,TNT also alleviates OS in macrophages,therefore inducing a higher portion of the M2 phenotype under OS with increased secretion of the anti-inflammatory cytokine IL-10,further promoting the osseoimmunity capacity compared with *** current study not only suggests the potential application of TiO2 nanotube-coated titanium implants in compromised conditions but also provides a systematic evaluation strategy for the future development of bone biomaterials.

关键词： Oxidative stress Osteogenesis TiO2 nanotubes FoxO1 Inflammation

Indole-3-acetic acid,a potential therapeutic target in Alzheimer's disease

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Science Bulletin 2024年第2期69卷 146-147页

作者： jinghong Li Department of Chemistry Center for Bioanalytical ChemistryKey Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology(Ministry of Education)Tsinghua UniversityBeijing 100084China

Alzheimer's disease(AD)is a chronic and progressive neurodegenerative disease that is characterized by the presence of amyloid-β(Ap)plaques,hyperphosphorylated microtubule-associated tau protein(p-tau)neurofibrillary tangles and neuronal *** to recent data,AD is the most common global cause of dementia in the *** billions of dollars have been invested in research,there is still no effective drug for the treatment of AD;consequently,this disease imposes a huge burden on individuals,families,and healthcare systems[1,2].

关键词： Alzheimer tau degeneration

基于步态特性分析的自适应零速检测行人导航方法

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自动化与仪器仪表 2024年第6期 1-5页

作者：刘思宇崔建民刘国栋张溢阅杨景宏北京理工大学光电学院信息光子技术工信部重点实验室北京100081

为了更快速精确地检测零速度,提出了一种自适应检测零速事件的行人导航方法。该方法首先根据惯性数据,以一个步态周期为一组,计算步行和跑步差异性特性标签;然后将计算出的标签通过支持向量机(SVM)判断运动状态;最后通过RNN神经网络使... 详细信息

为了更快速精确地检测零速度,提出了一种自适应检测零速事件的行人导航方法。该方法首先根据惯性数据,以一个步态周期为一组,计算步行和跑步差异性特性标签;然后将计算出的标签通过支持向量机(SVM)判断运动状态;最后通过RNN神经网络使用原始惯性数据结合运动状态确定输出是否为零速度事件,降低了计算成本。通过不同运动状态的多个实验对该方法进行了评价,在135.6 m的步行,跑步和步行-跑步复合运动中,水平位置误差分别为0.748,0.593和1.054 m,闭合定位误差为0.551%,0.438%和0.777%。

关键词：行人惯性导航零速修正运动轨迹运动分类

A new mixed type crack propagation criterion in shale reservoirs

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Petroleum 2024年第1期10卷 85-92页

作者： Muru Ding Zhirong Jin Yanjun Zhang jinghong Hu Beijing Key Laboratory of Unconventional Natural Gas Geology Evaluation and Development Engineering China University of Geosciences Sinopec Jiangsu Oil Field Branch Oil & Gas Technology Research Institute Changqing Oilefiled CompanyPetroChina

Hydraulic fracturing is a mainstream technology for unconventional oil and gas reservoirs development all over the world. How to use this technology to achieve high-level oil and gas resource extraction and how to form complex fracture networks as hydrocarbon transportation channels in tight reservoirs, which depends to a large extent on the interaction between hydraulic and pre-existing cracks. For hydraulic fracturing of fractured reservoirs, the impact of natural fractures, perforation direction, stress disturbances, faults and other influencing factors will produce a mixed I&II mode hydraulic fracture. To forecast whether hydraulic fractures cross pre-existing fractures, according to elastic mechanics and fracture mechanics, a stress state of cracks under the combination of tensile(I) and shear(II) is presented. A simple mixed-mode I&II hydraulic fracture's crossing judgment criterion is established, and the propagation of hydraulic fractures after encountering natural fractures is analyzed. The results show that for a given approaching angle there exists a certain range of stress ratio when crossing occurs. Under high approaching angle and large stress ratio, it is likely that hydraulic cracks will go directly through pre-existing cracks. The reinitiated angle is always controlled within the range of approximately 30°among the main direction of penetration.

关键词： Crack propagation criterion Stress ratio Approaching angle Reinitiated angle Mechanical model