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量子化学课程思政建设:揭示事物普遍联系的几个教学案例
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作者 张冬菊 朱荣秀 《大学化学》 CAS 2024年第7期272-277,共6页
量子化学是物理化学专业研究生的学位课程,其教学内容蕴含丰富的思政元素。本文以唯物辩证法的联系观为线索,通过典型教学案例,揭示联系的普遍性、客观性和多样性。这些教学案例旨在引导学生树立正确的辩证唯物主义世界观和方法论,学会... 量子化学是物理化学专业研究生的学位课程,其教学内容蕴含丰富的思政元素。本文以唯物辩证法的联系观为线索,通过典型教学案例,揭示联系的普遍性、客观性和多样性。这些教学案例旨在引导学生树立正确的辩证唯物主义世界观和方法论,学会用联系的观点去分析和解决问题,提高其科学素养和综合素质。 展开更多
关键词 量子化学 课程思政 唯物辩证法
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杂化轨道成键能力及夹角计算公式的简洁推导
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作者 张冬菊 刘艳红 《大学化学》 CAS 2023年第8期312-317,共6页
杂化轨道理论是化学键理论的重要内容,杂化轨道成键能力和杂化轨道之间的夹角是杂化轨道理论教学的重点和难点,多数教材通常直接给出相关公式,忽略导出过程,不能满足部分学生进阶学习的需要。本文给出了相关公式的简易推导,以期解疑释惑... 杂化轨道理论是化学键理论的重要内容,杂化轨道成键能力和杂化轨道之间的夹角是杂化轨道理论教学的重点和难点,多数教材通常直接给出相关公式,忽略导出过程,不能满足部分学生进阶学习的需要。本文给出了相关公式的简易推导,以期解疑释惑,加深学生对杂化轨道理论的认识和理解。 展开更多
关键词 杂化轨道理论 最大成键能力 杂化轨道夹角
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问题式教学法在结构化学教学中的应用:一维势箱中的粒子 被引量:3
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作者 张冬菊 马玉臣 《大学化学》 CAS 2022年第4期18-22,共5页
一维势箱中的粒子是结构化学课程中的重要内容,包含的知识点多、涉及面广、综合性强,采用“问题式教学法”围绕薛定谔方程的求解和结果讨论进行问题设计,以提出问题为切入点,引导学生通过分析问题和解决问题实现众多知识点的有机关联,... 一维势箱中的粒子是结构化学课程中的重要内容,包含的知识点多、涉及面广、综合性强,采用“问题式教学法”围绕薛定谔方程的求解和结果讨论进行问题设计,以提出问题为切入点,引导学生通过分析问题和解决问题实现众多知识点的有机关联,加深对量子力学基本原理的认识和理解,取得了较好的教学效果。 展开更多
关键词 结构化学 问题式教学法 一维势箱
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直链和单环共轭多烯本征行列式递推公式及本征能级的推导
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作者 张冬菊 蔡欣懿 宋其圣 《大学化学》 CAS 2022年第7期287-293,共7页
休克尔(Hückel)分子轨道法是描述共轭体系π电子运动的近似模型,《结构化学》教科书中通常直接给出其本征行列式和其本征能级的递推公式,缺乏推导过程。本文用数学归纳法推导了直链和单环共轭多烯本征多项的递推公式,给出了对应本... 休克尔(Hückel)分子轨道法是描述共轭体系π电子运动的近似模型,《结构化学》教科书中通常直接给出其本征行列式和其本征能级的递推公式,缺乏推导过程。本文用数学归纳法推导了直链和单环共轭多烯本征多项的递推公式,给出了对应本征能级的通式、特点和规律,适于未掌握群论和图论等数学工具的学生学习使用。 展开更多
关键词 共轭多烯 本征行列式 递推公式 本征能级
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Effects of Different Water-saving Irrigation Methods on Fruit Quality and Yield of Snow Melon
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作者 Xiudong SUN Yafei SUN +6 位作者 Zhongmou CHENG Weiqin XU Lili ZHOU Meixian GU Anna Guo Tingting JIANG dongju zhang 《Agricultural Biotechnology》 CAS 2021年第3期1-5,共5页
[Objectives]This study was conducted to explore the most suitable irrigation integration mode for"Tinglin snow melon"in Jinshan District,Shanghai City.[Methods]With the field water holding capacity as the st... [Objectives]This study was conducted to explore the most suitable irrigation integration mode for"Tinglin snow melon"in Jinshan District,Shanghai City.[Methods]With the field water holding capacity as the standard,different upper limits of irrigation were set in the four growth stage of snow melon to investigate the effects of such three water-saving irrigation modes as single-row drip irrigation pipes,double-row drip irrigation pipes and drip arrows on the traits and yield of melon plants under the same growth conditions.[Results]The results showed that different irrigation modes had certain effects on the growth,comprehensive quality and yield of snow melon,and the drop arrow mode was better than other two modes.Under the drop arrow mode,the number of snow melons was the highest,7.34 per plant,and the yield was the highest,reaching 15463.35 kg/hm^(2),showing the best yield increasing effect.In addition,the contents of soluble solids and vitamin C in the drop arrow mode were higher than those in the drip irrigation pipe mode.[Conclusions]Compared with other irrigation methods,the drop arrow mode was more suitable for the production of snow melon. 展开更多
关键词 Snow melon Drop irrigation Irrigation method Waster use efficiency Quality
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The evolution of prehistoric arrowheads in northern China and its influential factors
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作者 Juanting YAO Huan XIA +5 位作者 Ting LI Dongpeng LIN Yuanxin LI Xuke SHEN Jian WANG dongju zhang 《Science China Earth Sciences》 SCIE EI CAS CSCD 2023年第9期2109-2124,共16页
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 w... 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. 展开更多
关键词 Northern China Prehistoric arrowheads Spatio-temporal distribution Morphology changes Subsistence patterns
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青藏高原史前人类活动研究新进展 被引量:12
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作者 张东菊 申旭科 +4 位作者 成婷 夏欢 刘武 高星 陈发虎 《科学通报》 EI CAS CSCD 北大核心 2020年第6期475-482,共8页
青藏高原史前人类活动历史是近年多学科研究的热点科学问题.近年,对该问题的研究取得多项突破性进展,主要体现在青藏高原早期人类活动和现代藏族人群起源两个方面.最新两项考古学研究将青藏高原最早人类活动的时间分别推早至距今4万年... 青藏高原史前人类活动历史是近年多学科研究的热点科学问题.近年,对该问题的研究取得多项突破性进展,主要体现在青藏高原早期人类活动和现代藏族人群起源两个方面.最新两项考古学研究将青藏高原最早人类活动的时间分别推早至距今4万年和距今16万年,显示在现代人之前丹尼索瓦古老型智人(丹尼索瓦人)已经于中更新世开始了适应高原环境的征程.而最新两项独立的语言学和遗传学研究,均证明现代藏族人群主体来自距今5000年前后向青藏高原大规模扩散的仰韶文化和马家窑文化粟作农业人群.以上新成果,为深入理解史前人类向青藏高原的扩散和对高海拔环境的适应等问题提供了关键材料,同时也引发了更多关于青藏高原史前人类活动和东亚中晚更新世人类演化等问题的新思考,为将来开展更深入、更全面的研究提供了新线索. 展开更多
关键词 青藏高原 史前人类 藏族起源 高原适应
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丹尼索瓦人及其研究进展 被引量:4
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作者 夏欢 张东菊 陈发虎 《科学通报》 EI CAS CSCD 北大核心 2020年第25期2763-2774,共12页
根据2010年俄罗斯阿尔泰山丹尼索瓦洞出土的古人类手指骨的线粒体和全基因组测序分析结果,遗传学家提出并命名一支新的已灭绝古老型人类--丹尼索瓦人(Denisovans,简称为丹人).这支神秘的古人类引发了第四纪年代学、考古学、古人类学、... 根据2010年俄罗斯阿尔泰山丹尼索瓦洞出土的古人类手指骨的线粒体和全基因组测序分析结果,遗传学家提出并命名一支新的已灭绝古老型人类--丹尼索瓦人(Denisovans,简称为丹人).这支神秘的古人类引发了第四纪年代学、考古学、古人类学、遗传学等多领域学者们的广泛关注,相关研究取得显著进展.时空分布方面,化石记录显示丹人在丹尼索瓦洞的生活时间为195~52 ka,至少于160 ka已出现在青藏高原东北部的白石崖溶洞,已知的分布区域从阿尔泰山扩展至东亚地区;石器制作技术方面,丹尼索瓦洞的丹人可能使用了勒瓦娄哇和石叶技术,而白石崖溶洞的石制品则主要由简单石核石片技术打制而成;体质形态方面,丹尼索瓦洞出土的丹人化石碎片提供了指骨、牙齿等有限形态信息,夏河人右侧下颌骨化石则提供了丹人较为全面的下颌骨形态特征;遗传特征方面,丹人明显区别于同期主要分布于欧亚大陆西部的尼安德特人,且内部存在深度分化,并对大洋洲、东亚和南亚现生人群及美洲土著人群有着基因贡献.尽管新发现与新成果不断揭示丹人的特征信息,但我们对这一人群仍知之甚少,未来在白石崖溶洞遗址的持续发掘和深入研究,有望提供更多丹人的体质形态、遗传特征和文化内涵等信息,揭示丹人对高海拔环境的适应机制.此外,在中国开展丹人与东亚古老型智人和早期现代人之间关系的深入探讨,将有助于进一步推动东亚古人类演化研究. 展开更多
关键词 丹尼索瓦人 人类演化 现代人起源 西伯利亚 青藏高原
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Major advances in studies of the physical geography and living environment of China during the past 70 years and future prospects 被引量:14
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作者 Fahu CHEN Bojie FU +37 位作者 Jun XIA Duo WU Shaohong WU Yili zhang Hang SUN Yu LIU Xiaomin FANG Boqiang QIN Xin LI Tingjun zhang Baoyuan LIU Zhibao DONG Shugui HOU Lide TIAN Baiqing XU Guanghui DONG Jingyun ZHENG Wei YANG Xin WANG Zaijun LI Fei Wang Zhenbo HU Jie WANG Jianbao LIU Jianhui CHEN Wei HUANG Juzhi HOU Qiufang CAI Hao LONG Ming JIANG Yaxian HU Xiaoming FENG Xingguo MO Xiaoyan YANG dongju zhang Xiuhong WANG Yunhe YIN Xiaochen LIU 《Science China Earth Sciences》 SCIE EI CAS CSCD 2019年第11期1665-1701,共37页
The natural environment provides material essentials for human survival and development. The characteristics,processes, regional differentiation and forcing mechanisms of the elements of the natural environment(e.g. g... The natural environment provides material essentials for human survival and development. The characteristics,processes, regional differentiation and forcing mechanisms of the elements of the natural environment(e.g. geomorphology,climate, hydrology, soil, etc.) are the main objects of research in physical geography. China has a complex natural environment and huge regional differentiation and therefore it provides outstanding reserach opportunities in physical geography. This review summarizes the most important developments and the main contributions of research in the physical geography and human living environment in China during the past 70 years. The major topics addressed are the uplift of the Tibetan Plateau and the evolution of its cryosphere, the development of fluvial systems, the acidification of the vast arid region of the Asian interior, variations in the monsoon and westerly climate systems on multiple timescales, the development of lakes and wetlands, the watershed system model, soil erosion, past human-environment interactions, biogeography, and physical geographic zonality. After briefly introducing international research developments, we review the history of research in physical geography in China, focusing on the major achievements and major academic debates, and finally we summarize the status of current research and the future prospects. We propose that in the context of the national demand for the construction of an ecological civilization, we should make full use of the research findings of physical geography, and determine the patterns and mechanisms of natural environmental processes in order to continue to promote the continued contribution of physical geography to national development strategies, and to further contribute to the theory of physical geography from a global perspective. 展开更多
关键词 Physical GEOGRAPHY in China LIVING ENVIRONMENT Climate change TIBETAN PLATEAU Human-environment interactions
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Early human occupation of the Tibetan Plateau 被引量:10
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作者 dongju zhang Huan Xia Fahu Chen 《Science Bulletin》 SCIE EI CAS CSCD 2018年第24期1598-1600,共3页
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 ... 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). 展开更多
关键词 The TIBETAN PLATEAU AVERAGE ELEVATION human HISTORY
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Earliest parietal art:hominin hand and foot traces from the middle Pleistocene of Tibet 被引量:9
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作者 David D.zhang Matthew R.Bennett +15 位作者 Hai Cheng Leibin Wang Haiwei zhang Sally C.Reynolds Shengda zhang Xiaoqing Wang Teng Li Tommy Urban Qing Pei Zhifeng Wu Pu zhang Chunru Liu Yafeng Wang Cong Wang dongju zhang R.Lawrence Edwards 《Science Bulletin》 SCIE EI CSCD 2021年第24期2506-2515,M0004,共11页
At Quesang on the Tibetan Plateau we report a series of hand and foot impressions that appear to have been intentionally placed on the surface of a unit of soft travertine.The travertine was deposited by water from a ... At Quesang on the Tibetan Plateau we report a series of hand and foot impressions that appear to have been intentionally placed on the surface of a unit of soft travertine.The travertine was deposited by water from a hot spring which is now inactive and as the travertine lithified it preserved the traces.On the basis of the sizes of the hand and foot traces,we suggest that two track-makers were involved and were likely children.We interpret this event as a deliberate artistic act that created a work of parietal art.The travertine unit on which the traces were imprinted dates to between~169 and 226 ka BP.This would make the site the earliest currently known example of parietal art in the world and would also provide the earliest evidence discovered to date for hominins on the High Tibetan Plateau(above 4000 m a.s.l.).This remarkable discovery adds to the body of research that identifies children as some of the earliest artists within the genus Homo. 展开更多
关键词 TIBET Parietal art ICHNOLOGY HOMININ
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Subsistence strategies of prehistoric hunter-gatherers on the Tibetan Plateau during the Last Deglaciation 被引量:5
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作者 Jian WANG Huan XIA +4 位作者 Juanting YAO Xuke SHEN Ting CHENG Qianqian WANG dongju zhang 《Science China Earth Sciences》 SCIE EI CAS CSCD 2020年第3期395-404,共10页
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... 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. 展开更多
关键词 Tibetan Plateau Last Deglacial 151 site HUNTER-GATHERERS TAPHONOMY ZOOARCHAEOLOGY Subsistence strategy
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Earliest hand-and footprint art indicates that Denisovans may have occupied the interior of the high-altitude Tibetan Plateau since 200 thousand years ago 被引量:2
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作者 Fahu CHEN Huan XIA +1 位作者 Zhenxiu JIA dongju zhang 《Science China Earth Sciences》 SCIE EI CSCD 2022年第4期769-772,共4页
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 ... 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. 展开更多
关键词 Tibetan Plateau INTERIOR
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Reliability of radiocarbon dating on various fractions of loess-soil sequence for Dadiwan section in the western Chinese Loess Plateau
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作者 Zongli WANG Hui ZHAO +3 位作者 Guanghui DONG Aifeng ZHOU Jianbao LIU dongju zhang 《Frontiers of Earth Science》 SCIE CAS CSCD 2014年第4期540-546,共7页
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,... 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. 展开更多
关键词 loess-soil sequence humin fraction charcoal organic matter radiocarbon dating
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New portraits of the Denisovans
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作者 dongju zhang Huan Xia +1 位作者 Ting Cheng Fahu Chen 《Science Bulletin》 SCIE EI CSCD 2020年第1期1-3,M0003,共4页
Denisovans,well known for their high-coverage genetic sequences,are considered to be a new human species genetically distinct from Neanderthals and modern humans[1].As a close sister group of Neanderthals,Denisovans n... Denisovans,well known for their high-coverage genetic sequences,are considered to be a new human species genetically distinct from Neanderthals and modern humans[1].As a close sister group of Neanderthals,Denisovans not only interbred w让h Neanderthals[2],but they also contributed genetically to extant humans,including modern populations in parts of Oceania and Asia,aboriginal Americans and high-alt让ude modern Tibetans[3-5]. 展开更多
关键词 TIBETAN 丹尼索瓦人 SISTER
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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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作者 Yanhong Liu Rongxiu Zhu +1 位作者 Chengbu Liu dongju zhang 《Organic Chemistry Frontiers》 SCIE EI 2022年第1期147-155,共9页
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 betwee... 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. 展开更多
关键词 BORON coupling SALTS
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