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Cryogenian and Ediacaran integrative stratigraphy,biotas,and paleogeographical evolution of the Qinghai-Tibetan Plateau and its surrounding areas

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Science China Earth Sciences 2024年第4期67卷 919-949页

作者： Lang SUN Malik Muhammad Saud Sajid KHAN Chuan YANG Zhixin SUN Bing PAN Shehryar AHMED Lanyun MIAO Weichen SUN Chunlin hu Xiaojuan SUN Cui LUO bo CHEN Zongjun YIN Fangchen ZHAO Guoxiang LI Maoyan Zhu State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and PalaeontologyChinese Academy of SciencesNanjing 210008China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China

The complex evolutionary history of the Qinghai-Tibetan Plateau and its surrounding areas,including the continental blocks(Indian,Lhasa,South Qiangtang,Tarim,Olongbuluk,Central Qilian,Alxa,North China,Yangtze,Central Iran and Oman)and the orogenic belts between them,has long been the frontier in Earth science research.The Cryogenian and Ediacaran strata are extensively distributed in these blocks.Specifically,relatively complete Cryogenian and Ediacaran successions have been discovered in Oman,Indian,Yangtze,and Tarim blocks,while only the Ediacaran successions have been reported in Iran,the South Qiangtang,Central Qilian,Alxa,and North China blocks.Based on previous studies together with the integration of new materials and advancement obtained through the Second Tibetan Plateau Scientific Expedition and Research,this review aims to synthesize a correlative stratigraphic framework of the representative Cryogenian and Ediacaran sequences from the Qinghai-Tibetan Plateau and its surrounding areas.Furthermore,the Cryogenian and Ediacaran biotas and major geological events in these areas are comprehensively discussed in aspects of current research status.The results indicate that,in general,Ediacaran fossils of each area exhibit distinct features in preservation and assemblage composition,but the typical late Ediacaran fossils Cloudina and Shaanxilithes have been reported from most of these areas.In addition to the two global Cryogenian glaciations,late Ediacaran glaciogenic deposits are extensively recorded in the areas within and around the northern QinghaiTibetan Plateau(including the North China,Alxa,Central Qilian,Olongbuluk,and Tarim blocks,and the North Qilian Accretionary Belt),as well as central and southern Iran.However,further research is required to determine the age,distribution,and origin of these late Ediacaran glaciogenic deposits.Meanwhile,the middle Ediacaran DOUNCE/Shuram Excursion is widely documented in the Qinghai-Tibetan Plateau and its surrounding areas.The available data show that,after the

关键词： Qinghai-Tibetan Plateau Cryogenian Ediacaran Stratigraphy Palaeogeography Biota Gondwana

基于拓扑优化和缩尺试验的小宽厚比独柱式桥墩帽梁力学性能研究

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公路交通科技 2024年第5期41卷 97-107页

作者：胡赛鸿常柱刚邓海波丁磊长沙市城市建设投资开发集团有限公司湖南长沙410007 长沙市规划设计院有限责任公司湖南长沙410007

由于小宽厚比独柱墩帽梁属于典型的应力扰动区构件,内部受力较为复杂,普通独柱墩帽梁的设计方法可能对其不适用。对小宽厚比独柱墩帽梁模型进行拓扑优化,分析小宽厚比独柱墩帽梁的空间受力特征,根据拓扑优化结果建立小宽厚比独柱墩帽梁... 详细信息

由于小宽厚比独柱墩帽梁属于典型的应力扰动区构件,内部受力较为复杂,普通独柱墩帽梁的设计方法可能对其不适用。对小宽厚比独柱墩帽梁模型进行拓扑优化,分析小宽厚比独柱墩帽梁的空间受力特征,根据拓扑优化结果建立小宽厚比独柱墩帽梁的空间拉压杆模型基本构形,并根据最小应变能准则提出了确定其最优构型的方法。针对目前对小宽厚比独柱墩帽梁试验研究较少的现状,进行缩尺模型试验,研究其竖向静载作用下的受力特性。结果表明:在横桥向,帽梁顶部在双支座荷载下具有最大拉应力;在顺桥向,帽梁中间位置拉应力最大,帽梁的顶部拉应力低于中部,帽梁底部则表现出受压的趋势。由于未考虑顺桥向的力流扩散,根据相关规范中拉压杆模型设计方法计算得到的内力值与试验结果相差较大,说明规范法不适用于小宽厚比独柱墩帽梁的设计。试验结果的应力分布情况与根据拓扑优化结果提出的空间拉压杆模型一致,并且采用空间拉压杆模型计算得到的拉杆应力值相比规范法更加合理,证明本研究所提的空间拉压杆模型基本构形以及确定最优构型方法的合理性。

关键词：桥梁工程小宽厚比独柱墩帽梁空间拉压杆模型拓扑优化缩尺模型试验

急、慢性肾损伤患者血清中生物标志物的研究与验证

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中国病理生理杂志 2024年第2期40卷 335-342页

作者：丁璐刘胜胡波中山大学附属第三医院检验科广东广州510000

目的:探讨血清中中性粒细胞明胶酶相关脂质运载蛋白(neutrophil gelatinase-associated lipocalin,NGAL)及其他生物标志物在急、慢性肾损伤患者中的临床应用价值。方法:选取2022年1月~2023年7月在广州市中山大学附属第三医院就诊的急性... 详细信息

目的:探讨血清中中性粒细胞明胶酶相关脂质运载蛋白(neutrophil gelatinase-associated lipocalin,NGAL)及其他生物标志物在急、慢性肾损伤患者中的临床应用价值。方法:选取2022年1月~2023年7月在广州市中山大学附属第三医院就诊的急性肾损伤(acute kidney injury,AKI)患者171例及慢性肾脏病(chronic kidney disease,CKD)患者209例。收集各组成员的钾(K)、钠(Na)、氯(Cl)、二氧化碳(CO_(2))、尿素(Urea)和葡萄糖(GLU)数据。选取同时期健康体检者94例作为健康对照组,并用胶乳免疫比浊法检测3组成员血清中的NGAL水平。分析血清NGAL和其他生物标志物在鉴定急性和慢性肾损伤中的诊断有效性。采用多因素logistic回归方程分析影响AKI和CKD患者发生的因素。此外,还构建了受试者工作特征(receiver operating characteristic,ROC)曲线,以评估这些生物标志物在肾损伤患者中的临床意义。结果:通过生物信息学分析,提示NGAL可能是肾损伤的检测标志物。一般资料显示,在AKI组及CKD组中,K、Na、CO_(2)、Urea、GLU和NGAL水平均高于健康对照组(P<0.05)。多因素logistic回归方程分析显示,Na、Urea、GLU和NGAL水平均为AKI或者CKD疾病发生的独立危险因素(P<0.05)。ROC曲线分析结果显示,在AKI组中,Na、Urea、GLU和NGAL的曲线下面积(area under curve,AUC)分别为0.711、0.960、0.793和0.841(P<0.01);在CKD组中,Na、Urea、GLU和NGAL的AUC分别为0.681、0.990、0.703和0.930(P<0.01)。NGAL和Urea联合诊断AKI的灵敏度和特异性分别是81.9%和61.1%,诊断CKD的灵敏度和特异性分别是62.7%和80.0%。结论:血清NGAL可作为急、慢性肾损伤的指标,联合其他生物标志物在急、慢性肾损伤中也有一定的临床应用价值。

关键词：中性粒细胞明胶酶相关脂质运载蛋白生物标志物急性肾损伤慢性肾脏病

Enhancing the stability of Ni Fe-layered double hydroxide nanosheet array for alkaline seawater oxidation by Ce doping

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Journal of Energy Chemistry 2024年第4期91卷 306-312页

作者： Yongchao Yao Shengjun Sun hui Zhang Zixiao Li Chaoxin Yang Zhengwei Cai Xun He Kai Dong Yonglan Luo Yan Wang Yuchun Ren Qian Liu Dongdong Zheng Weihua Zhuang bo Tang Xuping Sun Wenchuang(Walter)hu Department of Laboratory Medicine West China HospitalSichuan UniversityChengdu 610041SichuanChina College of Chemistry Chemical Engineering and Materials ScienceShandong Normal UniversityJinan 250014ShandongChina Institute of Fundamental and Frontier Sciences University of Electronic Science and Technology of ChinaChengdu 610054SichuanChina Institute for Advanced Study Chengdu UniversityChengdu 610106SichuanChina Laoshan Laboratory Qingdao 266237ShandongChina

Electrocatalytic hydrogen production from seawater holds enormous promise for clean energy generation.Nevertheless,the direct electrolysis of seawater encounters significant challenges due to poor anodic stability caused by detrimental chlorine chemistry.Herein,we present our recent discovery that the incorporation of Ce into Ni Fe layered double hydroxide nanosheet array on Ni foam(Ce-Ni Fe LDH/NF)emerges as a robust electrocatalyst for seawater oxidation.During the seawater oxidation process,CeO_(2)is generated,effectively repelling Cl^(-)and inhibiting the formation of Cl O-,resulting in a notable enhancement in the oxidation activity and stability of alkaline seawater.The prepared Ce-Ni Fe LDH/NF requires only overpotential of 390 m V to achieve the current density of 1 A cm^(-2),while maintaining long-term stability for 500 h,outperforming the performance of Ni Fe LDH/NF(430 m V,150 h)by a significant margin.This study highlights the effectiveness of a Ce-doping strategy in augmenting the activity and stability of materials based on Ni Fe LDH in seawater electrolysis for oxygen evolution.

关键词： Ce doping NiFe layered double hydroxide Seawater oxidation Electrocatalysis Cl^(-) repulsion

Multiomics analyses of two Leonurus species illuminate leonurine biosynthesis and its evolution

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Molecular Plant 2024年第1期17卷 158-177页

作者： Peng Li Meng-Xiao Yan Pan Liu Dan-Jie Yang Ze-Kun He Yun Gao Yan Jiang Yu Kong Xin Zhong Sheng Wu Jun Yang Hong-Xia Wang Yan-bo huang Le Wang Xiao-Ya Chen Yong-Hong hu Qing Zhao Ping Xu shanghai Key Laboratory of Plant Functional Genomics and Resources Shanghai Chenshan Botanical GardenShanghai Chenshan Plant Science Research CenterChineseAcademy of SciencesShanghaiChina College of Life Sciences Shanghai Normal UniversityShanghai 200234China State Key Laboratory of Plant Molecular Genetics CAS Center for Excellence in Molecular Plant SciencesChinese Academy of SciencesShanghaiChina University of the Chinese Academy of Sciences Beijing 100049China The Research Center of Chiral Drugs Innovation Research Institute of Traditional Chinese MedicineShanghai University of Traditional Chinese Medicine1200 Cailun RoadShanghai 201203China College of Chemistry and Chemical Engineering Shanghai University of Engineering ScienceShanghai 201620China

The Lamiaceae family is renowned for its terpenoid-based medicinal components,but Leonurus,which has traditional medicinal uses,stands out for its alkaloid-rich composition.Leonurine,the principal active compound found in Leonurus,has demonstrated promising effects in reducing blood lipids and treating strokes.However,the biosynthetic pathway of leonurine remains largely unexplored.Here,we present the chromosome-level genome sequence assemblies of Leonurus japonicus,known for its high leonurine production,and Leonurus sibiricus,characterized by very limited leonurine production.By integrating genomics,RNA sequencing,metabolomics,and enzyme activity assay data,we constructed the leonurine biosynthesis pathway and identified the arginine decarboxylase(ADC),uridine diphosphate glucosyltransferase(UGT),and serine carboxypeptidase-like(SCPL)acyltransferase enzymes that catalyze key reactions in this pathway.Further analyses revealed that the UGT–SCPL gene cluster evolved by gene duplication in the ancestor of Leonurus and neofunctionalization of SCPL in L.japonicus,which contributed to the accumulation of leonurine specifically in L.japonicus.Collectively,our comprehensive study illuminates leonurine biosynthesis and its evolution in Leonurus.

关键词： Lamiaceae Leonurus japonicus Leonurus sibiricus genome sequence alkaloids leonurine gene cluster biosynthetic pathway evolution

钆含量对Fe-B-Nb-Gd非晶合金磁学性能和氧化机制的影响规律

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物理学报 2024年第9期73卷 254-262页

作者：糜晓磊胡亮武博文龙强魏炳波西北工业大学物理科学与技术学院西安710072

研究了Gd含量对(Fe_(73)B_(22)Nb_(5))_(100–x)Gd_(x)(x=0,0.5,1.0,1.5,2.0)合金非晶形成能力、热稳定性和磁学性能的影响规律,并对比分析了非晶氧化机制.通过添加Gd元素,合金的原子尺寸差超过13%,构型熵增大了30%,提升了合金的非晶形... 详细信息

研究了Gd含量对(Fe_(73)B_(22)Nb_(5))_(100–x)Gd_(x)(x=0,0.5,1.0,1.5,2.0)合金非晶形成能力、热稳定性和磁学性能的影响规律,并对比分析了非晶氧化机制.通过添加Gd元素,合金的原子尺寸差超过13%,构型熵增大了30%,提升了合金的非晶形成能力.随着Gd含量的增大,过冷液相区范围达到73 K,热稳定性得到明显增强.Gd元素导致合金局部各向异性受到限制,准位错偶极子型缺陷密度降低.这有效减少了阻碍磁畴壁旋转的钉扎位点,提高合金软磁性能.此外,Gd元素使得非晶在氧化过程中对温度的变化更为敏感,达到最大氧化速率的温度降低了15 K,但是并未恶化其抗氧化性能.Gd原子受结合能影响向表层迁移,形成的富Gd氧化物填充了表层缺陷,占据了大量顶部空间,合金表面附近的结构更加致密.这种结构减少了氧原子通过微观组织界面进行扩散的通道,有助于增强抗氧化性能.

关键词：稀土元素非晶合金快速凝固氧化机制

A Well Productivity Model for Multi-Layered Marine and Continental Transitional Reservoirs with Complex Fracture Networks

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Fluid Dynamics & Materials Processing 2024年第6期20卷 1313-1330页

作者： huiyan Zhao Xuezhong Chen Zhijian hu Man Chen bo Xiong Jianying Yang Sichuan Changning Natural Gas Development Company Limited PetroChina Southwest Oil and Gas Field CompanyYibin644399China Sichuan Shale Gas Exploration and Development Company Limited PetroChina Southwest Oil and Gas Field CompanyNeijiang641100China New Energy Division PetroChina Southwest Oil and Gas Field CompanyChengdu610051China

Using the typical characteristics of multi-layered marine and continental transitional gas reservoirs as a basis,a model is developed to predict the related well production rate.This model relies on the fractal theory of tortuous capillary bundles and can take into account multiple gas flow mechanisms at the micrometer and nanometer scales,as well as the flow characteristics in different types of thin layers(tight sandstone gas,shale gas,and coalbed gas).Moreover,a source-sink function concept and a pressure drop superposition principle are utilized to introduce a coupled flow model in the reservoir.A semi-analytical solution for the production rate is obtained using a matrix iteration method.A specific well is selected for fitting dynamic production data,and the calculation results show that the tight sandstone has the highest gas production per unit thickness compared with the other types of reservoirs.Moreover,desorption and diffusion of coalbed gas and shale gas can significantly contribute to gas production,and the daily production of these two gases decreases rapidly with decreasing reservoir pressure.Interestingly,the gas production from fractures exhibits an approximately U-shaped distribution,indicating the need to optimize the spacing between clusters during hydraulic fracturing to reduce the area of overlapping fracture control.The coal matrix water saturation significantly affects the coalbed gas production,with higher water saturation leading to lower production.

关键词： Marine-continental transitional reservoir multi-layered reservoir seepage mechanisms apparent permeability hydraulic horizontal well productivity model

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水下声学超表面异常折射方向调控研究

哈尔滨工程大学学报 2024年第1期45卷 93-102页

作者：胡博刘凯赵思缘李松哈尔滨工程大学水声技术全国重点实验室黑龙江哈尔滨150001 海洋信息获取与安全工业和信息化部重点实验室(哈尔滨工程大学) 黑龙江哈尔滨150001 哈尔滨工程大学水声工程学院黑龙江哈尔滨150001 中国船舶科学研究中心江苏无锡214082

针对波束调控的问题,本文提出了一种控制波前相位的声学超表面。本文依据广义斯奈尔定律,利用不同声速的均匀介质构建了水中多频声学超表面模型,给出声学超表面产生异常声折射的基本原理,验证了声学超表面在多个频点下可以实现异常声折... 详细信息

针对波束调控的问题,本文提出了一种控制波前相位的声学超表面。本文依据广义斯奈尔定律,利用不同声速的均匀介质构建了水中多频声学超表面模型,给出声学超表面产生异常声折射的基本原理,验证了声学超表面在多个频点下可以实现异常声折射现象,揭示了频率以及声波入射角对声学超表面异常折射现象的影响规律,制备了声学超表面实物在水箱中对理论结果进行验证。结果表明:在入射波频率为基频的整数倍时,超表面模型可以实现折射角相同的异常折射现象,并且入射角在一定范围内可以实现负折射现象。实验测量了水中钢板和超表面的折射情况,相较于均匀介质,在不同入射角度下设计的超表面均可以实现异常折射,并且测量值与理论值吻合较好。

关键词：水下声学超表面异常折射负折射梯度相位广义斯奈尔定律多角度消声水箱

An air-stable single-crystal layered oxide cathode based on multifunctional structural modulation for high-energy-density sodium-ion batteries

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Science China Chemistry 2024年

作者： Yi-Feng Liu hai-Yan hu Jia-Yang Li Hongrui Wang Yi Zhao Jingqiang Wang Yuan-bo Wu Yan-Jiang Li Guang-Yu Zhang Qing-Qun Sun Yan-Fang Zhu Rui-Ren Tang Xiong-Wei Wu Jia-Zhao Wang Shi-Xue Dou Shu-Lei Chou Yao Xiao Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education) Nankai University School of Chemistry and Materials Science Hunan Agricultural University Institute of Energy Materials Science University of Shanghai for Science and Technology Wenzhou Key Laboratory of Sodium-Ion Batteries Wenzhou University Technology Innovation Institute for Carbon Neutralization Institute for Carbon Neutralization College of Chemistry and Materials Engineering Wenzhou University College of Chemistry and Chemical Engineering Central South University

P2-type layered oxide, Na2/3Ni1/3Mn2/3O2, has drawn particular interest as a promising cathode material for sodium-ion batteries(SIBs) due to its fast sodium-ion transport channels with low migration potential. However, some catastrophic flaws, such as air instability, complicated multiphase evolution, and irreversible anionic redox, limit its electrochemical performance and hinder its application. Here, an air-stable single-crystal P2-type Na2/3Ni1/3Mn1/3Ti1/3O2is proposed based on the multifunctional structural modulation of Ti substitution that could alleviate the issues for practical SIBs. As a result, the cathode with high energy density shows excellent air stability and highly reversible phase transitions(P2–OP4), and delivers faster kinetics and stable anion redox chemistry. Meanwhile, a thorough investigation of the relationship between structure, function, and properties is demonstrated,emphasizing formation processes, electrochemical behavior, structural evolution, and air stability. Overall, this study provides the direction of multifunctional structural modulation for the development of high-performance sodium-based layered cathode materials for practical applications.

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