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Science China Earth Sciences 2022年第4期65卷 769-772页

作者： Fahu CHEN Huan XIA Zhenxiu JIA dongju zhang Group of Alpine Paleoecology and Human Adaptation(ALPHA) Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China State Key Laboratory of Tibetan Plateau Earth System Resources and Environment(TPESRE)Beijing 100101China MOE Key Laboratory of Western China’s Environmental System Lanzhou UniversityLanzhou 730000China

As a result of rapid uplift since the late Cenozoic, the Tibetan Plateau eventually developed an enormous area(3.08 million km^(2)) and became the highest elevation plateau on Earth. The cold and hypoxic environments of the Tibetan Plateau,combined with the strong solar radiation receipt and lack of biological resources, present a major challenge to the occupation and expansion of humans.

关键词： Tibetan Plateau interior

Key role of aπ–πcomplex in diaryl cross-coupling between aryldiazonium salts and arylboronic acids using photosensitizer-free gold/photoredox catalysis

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Organic Chemistry Frontiers 2022年第1期9卷 147-155页

作者： Yanhong Liu Rongxiu Zhu Chengbu Liu dongju zhang Key Laboratory of Colloid and Interface Chemistry Ministry of EducationInstitute of Theoretical ChemistrySchool of Chemistry and Chemical EngineeringShandong UniversityJinan 250100P.R.China

DFT and TD-DFT calculations were performed to better understand the photosensitizer-free visible-lightmediated Au-catalyzed cross-coupling between aryldiazonium salts and arylboronic acids.Theπ–πtype complex between the aryldiazonium salt and the arylboronic acid,rather than either the generally accepted gold(I)–aryldiazonium salt complex or the aryldiazonium salt itself,was shown to play the role of a virtual photoinitiator.The oxidation of Au(I)to Au(III),the key aspect of the dual gold/photoredox catalytic aryl–aryl cross-coupling,occurs via the radical addition of an aryl radical rather than an aryldiazo radical on Au(II)species.The transmetalation of the arylboronic acid to Au(III)species was identified as the rate-determining step,and the presence of a tetrafluoroborate anion can assist this process remarkably.The experimentally observed effect of substituents on the aryldiazonium salt and boronic acid on the reactivity was also rationalized.

关键词： boron coupling salts

The evolution of prehistoric arrowheads in northern China and its influential factors

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Science China Earth Sciences 2023年第9期66卷 2109-2124页

作者： Juanting YAO Huan XIA Ting LI Dongpeng LIN Yuanxin LI Xuke SHEN Jian WANG dongju zhang Key Laboratory of Western China’s Environmental Systems(Ministry of Education) College of Earth and Environmental SciencesLanzhou UniversityLanzhou 730000China

Prehistoric projectile weapons are crucial for understanding the hunting behavior,survival strategies,and subsistence patterns of prehistoric humans.Arrowheads were the primary prehistoric projectile weapon,and here we review the spatiotemporal distribution and changes in the morphology,quantity,and materials composition of arrowheads in the northern regions of China from the Middle and Upper Paleolithic periods to the Bronze Age,together with the factors that influenced these changes.The results reveal that primitive stone arrowheads appeared sporadically in the Middle Paleolithic period.Additionally,the“broad spectrum revolution”and microblade technology during the Upper Paleolithic promoted the regional-scale diffusion of broad and thick stone arrowheads in northern China.During the Neolithic period,relatively narrow and thin stone and bone arrowheads spread rapidly across the entire Yellow River Basin and most of northeastern China.The dominance of these two types of arrowheads alternated,during the period of 7000–5000 yr BP,the number of arrowheads peaked,possibly closely related to changes in the role of hunting(fishing and hunting)and gathering in the subsistence economy,human population size,and the emergence and development of a grinding technology.During the Bronze Age,a significant number of bronze arrowheads appeared,and the total number of arrowheads increased again,and their distribution expanded to northwestern China.The emergence of a bronze smelting technology and inter-group conflicts may have been the primary factors influencing this trend.Our results demonstrate that arrowheads were always an essential component of prehistoric tool kits.Due to technological developments in subsistence strategies,the morphology,function,and popularity of arrowheads underwent substantial changes during different periods.Therefore,a comprehensive study of prehistoric arrowheads can help better understand the subsistence patterns and processes of economic and societal development of prehistoric humans.

关键词： Northern China Prehistoric arrowheads Spatio-temporal distribution Morphology changes Subsistence patterns

Early human occupation of the Tibetan Plateau

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Science Bulletin 2018年第24期63卷 1598-1600页

作者： dongju zhang Huan Xia Fahu Chen Key Laboratory of Western China's Environmental Systems (Ministry of Education) College of Earth Environmental SciencesLanzhou University Key Laboratory of Alpine Ecology (LAE) CAS Center for Excellence in Tibetan Plateau Earth System SciencesInstitute of Tibetan Plateau ResearchChinese Academy of Sciences

The Tibetan Plateau,the world's "Third Pole",has an average elevation above 4,000 masl (meters above sea level)and an area of over 500×10^4km^2,It is the highest and largest plateau on earth and is very sensitive to global climate change [1,2].The cold,dry and hypoxic high-altitude environment of the plateau presents a major challenge to human survival.Therefore,the history and mechanisms of prehistoric human history on the Tibetan Plateau-from brief hunting expeditions to seasonal hunting-gathering and finally to permanent settlements-has attracted both general interest and substantial scientific debates [3-6].Archaeological studies indicate that humans probably first explored the plateau at the end of the late Pleistocene.They practiced intensive seasonal hunting-gathering from 15 ka BP [6],and permanently settled regions above 3,000 masl after 3.6 ka BP,which was facilitated by the development of an agropastoral economy [3].However, the early part of the human history of the Tibetan Plateau is still poorly documented,due to the lack of well-preserved archaeological sites and reliable dating results (Fig.la).

关键词： The Tibetan Plateau average elevation human history

Subsistence strategies of prehistoric hunter-gatherers on the Tibetan Plateau during the Last Deglaciation

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Science China Earth Sciences 2020年第3期63卷 395-404页

作者： Jian WANG Huan XIA Juanting YAO Xuke SHEN Ting CHENG Qianqian WANG dongju zhang Key Laboratory of Western China’s Environmental Systems(Ministry of Education) College of Earth Environmental SciencesLanzhou UniversityLanzhou 730000China Qinghai Provincial Institute of Cultural Relics and Archaeological Research Xining 810007China

The study of prehistoric hunter-gatherer subsistence strategies on the Tibetan Plateau is important for understanding the mechanisms and processes of human adaption to high altitude environments.But to date,only a few Paleolithic sites have been found on the Tibetan Plateau with clear stratigraphy and reliable dating.These sites are mainly distributed in the Qinghai Lake Basin on the northeastern part of the plateau,and the sporadic fauna and flora remains excavated provide limited information about the subsistence strategies of hunter-gatherers.In 2014,relatively abundant animal remains were unearthed in the Lower Cultural Layer (LCL,15400-13100 cal yr BP) of the"151 site"located in the Qinghai Lake Basin,providing important information about human subsistence strategies on the Tibetan Plateau during the Last Deglaciation.Zooarchaeological analysis of these faunal remains indicates that hunter-gatherers at the"151 site"mainly targeted large ungulates of Bos and wild horse/ass,and only brought back the most nutritious parts of animal carcasses including upper and intermediate limb bones,heads,and trunks (ribs and vertebrae).People then processed and consumed the carcasses around single hearths.Our comprehensive analyses of contemporaneous sites in the Qinghai Lake Basin show that a subsistence strategy involving opportunistic hunting of ungulates,high mobility,and short occupation of campsites was used by terminal Pleistocene huntergatherers to adapt to the high-altitude environment on the Tibetan Plateau.This subsistence strategy may have been a first step of gradual hunter-gatherer adaptation to the extreme conditions on the Tibetan Plateau after the Last Glacial Maximum,and laid the foundation for the widespread distribution of hunter-gatherers on the plateau during the Holocene.

关键词： Tibetan Plateau Last Deglacial 151 site Hunter-gatherers Taphonomy Zooarchaeology Subsistence strategy

Reliability of radiocarbon dating on various fractions of loess-soil sequence for Dadiwan section in the western Chinese Loess Plateau

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Frontiers of Earth Science 2014年第4期8卷 540-546页

作者： Zongli WANG Hui ZHAO Guanghui DONG Aifeng ZHOU Jianbao LIU dongju zhang MOE Key Laboratory of West China's Environmental System Lanzhou University Lanzhou 730000 China Key Laboratory of Desert and Desertification Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China

The accurate radiocarbon dating of loess-soil sequences plays an essential role in the reconstruction of the environmental and climatic changes in continental settings during the last glaciation and Holocene. However, our knowledge about the reliability of radiocarbon ages of various fractions of soil and loess samples is still insufficient. Here, we present our study results on radio- carbon ages based on bulk organic matter, humin fraction, and carbonate of samples collected from a loess-paleosol section in the western Chinese Loess Plateau. We compare these observations with the optically stimulated luminescence ages and charcoal radiocarbon ages to evaluate the reliability of these fractions. We observed that the radio- carbon ages of humin fraction are very close to those of charcoal and are consistent with the optically stimulated luminescence ages within the experimental errors. We observed a significant deviation in the radiocarbon ages of carbonate and bulk organic matter from those of charcoal and optically stimulated luminescence ages, likely due to the dilution of these fractions during the pedogenetic process. Our results reveal that, except for charcoal, the humin fraction may yield reliable laC ages for the Chinese loess-soil sequence.

关键词： loess-soil sequence humin fraction charcoal,organic matter radiocarbon dating

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晶体结构教学中的基本概念表述与内涵的探讨

大学化学 2024年第3期39卷 18-22页

作者：张冬菊山东大学化学与化工学院济南250100

晶体结构是结构化学课程中的重要教学内容,包含的知识点多、概念抽象、理论性强。本文探讨晶体结构教学中一些基本概念的表述与内涵,包括点阵、晶格、结构基元、晶胞等,以期帮助学生澄清一些模糊不清的认识,引导学生正确理解晶体学理论... 详细信息

晶体结构是结构化学课程中的重要教学内容,包含的知识点多、概念抽象、理论性强。本文探讨晶体结构教学中一些基本概念的表述与内涵,包括点阵、晶格、结构基元、晶胞等,以期帮助学生澄清一些模糊不清的认识,引导学生正确理解晶体学理论的基础知识和基本概念。

关键词：点阵晶格结构基元晶胞

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“互联网+医院-家庭智慧护理”模式在肠造口病人居家护理中的应用

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循证护理 2024年第13期10卷 2439-2443页

作者：张冬菊王玮徐州医科大学附属宿迁医院江苏223800

目的:探讨“互联网+医院-家庭智慧护理”模式在肠造口病人居家护理中的应用效果。方法:选取2021年3月—2023年3月江苏省某医院收治的92例直肠癌肠造口病人为研究对象,采用随机数字表法将病人分为观察组及对照组,各46例。对照组实施常规... 详细信息

目的:探讨“互联网+医院-家庭智慧护理”模式在肠造口病人居家护理中的应用效果。方法:选取2021年3月—2023年3月江苏省某医院收治的92例直肠癌肠造口病人为研究对象,采用随机数字表法将病人分为观察组及对照组,各46例。对照组实施常规护理模式,观察组实施“互联网+医院-家庭智慧护理”模式,干预时间6个月,比较两组病人干预前后造口自我管理效能、造口自护能力、生活质量及造口相关并发症发生率。结果:两组病人干预后造口自我管理效能评分、自护能力评分、生活质量评分及造口相关并发症发生率比较差异均有统计学意义(P<0.05)。结论:“互联网+医院-家庭智慧护理”模式有助于提升直肠癌造口病人自我管理效能及自我护理能力,降低造口相关并发症,提高生活质量。

关键词： “互联网+” 智慧护理直肠癌肠造口自护能力生活质量居家护理

理论化学方法阐明化学反应热力学控制与动力学控制的概念——推荐一个Diels-Alder反应的计算化学实验

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大学化学 2024年第3期39卷 327-335页

作者：杨一莹张冬菊山东大学化学与化工学院济南250100

设计了一个适用于化学专业高年级本科生的综合计算化学实验。该实验通过量子化学计算,研究了有机化学教材中一个典型的Diels-Alder反应,给出了反应过程的微观物理图像以及反应的热力学和动力学性质的定量信息,阐明了化学反应中热力学控... 详细信息

设计了一个适用于化学专业高年级本科生的综合计算化学实验。该实验通过量子化学计算,研究了有机化学教材中一个典型的Diels-Alder反应,给出了反应过程的微观物理图像以及反应的热力学和动力学性质的定量信息,阐明了化学反应中热力学控制和动力学控制的基本概念。该实验旨在培养学生使用计算化学方法研究化学问题的基本技能,加深其对物质结构与性能之间关系的理解。该实验也是对学生进行辩证唯物主义世界观和方法论教育的一个具体实例,着重引导学生充分认识矛盾的普遍性,擅于用联系观和发展观分析和解决化学实际问题。

关键词：计算化学热力学控制动力学控制 Diels-Alder反应

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典型频哪醇重排反应的机理及基团迁移规律的研究——一个研究型计算化学实验

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大学化学 2024年第4期39卷 305-313页

作者：赵容浩梁一钒史梦瑶朱荣秀张冬菊山东大学化学与化工学院济南250100

频哪醇重排是本科有机化学课程的重要内容,但学生对重排机理、区域选择性和基团迁移规律不能很好地理解掌握。为了加强学生对频哪醇重排反应的理解,我们设计了一个利用计算化学方法解决有机化学问题的实验。通过直观的图像和具体的数据... 详细信息

频哪醇重排是本科有机化学课程的重要内容,但学生对重排机理、区域选择性和基团迁移规律不能很好地理解掌握。为了加强学生对频哪醇重排反应的理解,我们设计了一个利用计算化学方法解决有机化学问题的实验。通过直观的图像和具体的数据清楚地展现出:能形成稳定碳正离子中间体的底物主要以分步重排机理进行,而不能形成稳定中间体的底物则按协同重排机理进行。计算结果验证了反应的区域选择性取决于邻二醇质子化羟基的位置以及基团的迁移能力,明确了基团迁移能力的顺序为氢>芳基>烷基,并从微观角度对其进行了合理解释。

关键词：频哪醇重排反应机理迁移能力密度泛函理论计算

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