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Journal of Mountain Science 2021年第2期18卷 307-322页

作者： YANG Wei-lin HAN Ye-song PENG Xu RAN Ze-ze liu Qing liu geng-nian College of Urban and Environmental Sciences Peking UniversityBeijing 100871China

Owing to the remoteness of the Longriba area and the lack of dating records,it is extremely challenging to reconstruct the chronology and extent of the paleoglaciers in this *** this paper,we combined limited observational data with automated modelling for paleoglacial *** first identified a broadly distributed paleoglacier from satellite imagery and field investigation based on the sediment-landform assemblage principle and dated it to 23.1±1.4~19.5±1.2 ka by ^(10)Be exposure dating,corresponding to the global Last Glacial Maximum(gLGM).Then,we reconstructed the extent and ice surface of 171 paleoglaciers formed during the similar period based on geomorphological evidence and‘ice surface profile’*** results showed that the paleoglacial coverage was 426.5 km2,with an ice volume of 38.1 km^(3),in the Longriba *** reconstructed equilibrium line altitudes(ELAs)based on modelled ice surfaces yielded an average of 4245±66 m above sea level(asl),~725±73 m lower than the present ELA(4970±29 m asl).The temperature was~5.51-6.68℃lower,and the precipitation was~30-34%less in Longriba,during the gLGM compared to the present *** glacial advance was mainly driven by colder climate that was synchronous with Northern Hemisphere cooling events.

关键词： Ice surface profile ^(10)Be surface exposure dating Paleoglacial reconstruction Paleoclimate reconstruction Global Last Glacial Maximum Eastern Tibetan Plateau

The property, age and formation environment of the palaeokarst in Qinghai-Xizang Plateau

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Journal of Geographical Sciences 2002年第2期12卷 21-29页

作者： Gao Quan-zhou Cui Zhi-jiu Tao Zhen liu geng-nian Hong Yun Department of Geography Zhongshan University Guangzhou China Department of Geography Peking University Beijing China State Environmental Protection Administration Beijing China

The karst landforms distributed on the Qinghai-Xizang (Tibet) Plateau can be genetically classed with the Tertiary underground karst, which were gradually exhumed to the surface with the uplift of the plateau during Quaternary period. The relative deposits of the Tertiary palaeokarst processes, such as the residuum and speleothem, were discovered recently in the southern and southeastern fringe areas of the plateau, where has geological-currently been disintegrated by the headward erosion processes of the modern river systems. The major chemical components of the clay portion of the residuum consist mainly of SiO2, Al2O3 and Fe2O3. The clay minerals composition of the clay portion belongs to illite-kaolinite pattern for most of the residuum samples, and kaolinite-illite pattern for a few of the samples. It can be judged from the silicic acid index and the clay minerals composition that the formation of the residuum of the Plateau was in its initial phase. However, such a lower chemical weathering index only reflected the weathering degree in the bottom or lower parts of the lateritic weathering crust. The relatively intensive chemical weathering processes of the surface layers of the lateritic weathering crust could be logically speculated. The surface feature textures of quartz grains in the residuum were formed mainly by the chemical erosion, which revealed a long-term humid-tropical environment when the residuum and the palaeokarst formed.

关键词： palaeokarst lateritic residuum chemical weathering Tertiary Period planation surface Qinghai-Xizang Plateau

冰川槽谷横剖面沿程变化及其对冰川动力的反映

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地理学报 2000年第2期55卷 235-242页

作者：李英奎刘耕年北京大学城市与环境学系北京100871

冰川槽谷梯级宽深比定义为槽谷横剖面上相同等高线间距离与对应深度的比值。它可以描述槽谷横剖面形态的总体特征 ,便于不同槽谷横剖面形态的对比。统计分析表明槽谷梯级宽深比随槽谷深度的变化符合幂函数模型。使用这一模型描述冰川槽... 详细信息

冰川槽谷梯级宽深比定义为槽谷横剖面上相同等高线间距离与对应深度的比值。它可以描述槽谷横剖面形态的总体特征 ,便于不同槽谷横剖面形态的对比。统计分析表明槽谷梯级宽深比随槽谷深度的变化符合幂函数模型。使用这一模型描述冰川槽谷横剖面的总体形态并据此探讨冰川槽谷横剖面形态的沿程变化。主要结论如下 :简单槽谷从上源到雪线附近 ,模型参数显示为槽谷展宽 ,谷壁变陡 ,从雪线向下游 ,槽谷变窄 ,谷壁变缓 ;从简单槽谷段向复合槽谷段 ,槽谷明显展宽 ,谷壁变陡 ,从复合槽谷段向单流槽谷段 ,槽谷变窄。

关键词：冰川动力冰川槽谷横剖面沿程变化

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天山玛纳斯河源鹿角湾冰川地貌与冰期序列

冰川冻土 2005年第6期27卷 907-912页

作者：鞠远江刘耕年中国矿业大学资源学院江苏徐州221008 北京大学环境学院北京100871

在鹿角湾冰川区40 km2的考察范围内, 共发育了18个冰斗. 按斗底高度的不同, 可以将18个冰斗分成3个高度等级, 分别代表了3次雪线高度不同的冰进. 冰斗朝向以偏北为主, 说明水热条件对冰斗发育是限制因素. 18号冰斗和2号冰斗朝向偏南, ... 详细信息

在鹿角湾冰川区40 km2的考察范围内, 共发育了18个冰斗. 按斗底高度的不同, 可以将18个冰斗分成3个高度等级, 分别代表了3次雪线高度不同的冰进. 冰斗朝向以偏北为主, 说明水热条件对冰斗发育是限制因素. 18号冰斗和2号冰斗朝向偏南, 说明其所代表的冰进阶段水热条件组合有利于冰川的长期存在, 从而发育了大规模的向阳冰斗. 鹿角湾冰川共发育了10道保存比较完整的冰碛垄, 按冰碛垄表面特征和产出位置, 结合测年资料, 将10道冰碛垄划分为5套冰碛地层. 对冰碛垄上所采冰碛土样品进行年代测试的结果是: 冰碛丘陵上组地层属于小冰期沉积, 较早的两次冰进结束时间为(680±60)a BP和(250±60)a BP; 冰碛丘陵组地层属于新冰期沉积, 3次冰进结束年代分别为: (4.2±0.4)ka BP, (2.9±0.3)ka BP, (1 720±60)a BP; 末次冰期晚期结束年代为1.1～1.2 ka BP.其它几次冰进阶段未能取得可信的测年数据.

关键词：天山玛纳斯河源地貌冰期序列

山地冰川平衡线高度作为气候变化代用指标的讨论

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冰川冻土 2007年第4期29卷 613-616页

作者：鞠远江刘耕年魏遐中国矿业大学资源学院江苏徐州221008 北京大学环境学院北京100871 浙江财经学院工商管理学院浙江杭州310012

对以平衡线高度作为气候变化代用指标的理论依据进行了讨论,依据天山乌鲁木齐河源1号冰川的大量观测资料,建立和完善现代冰川平衡线高度与气候统计关系,从传统方法以区域范围内气候因子为参数改造为以冰川范围内气候因子为参数,通过检... 详细信息

对以平衡线高度作为气候变化代用指标的理论依据进行了讨论,依据天山乌鲁木齐河源1号冰川的大量观测资料,建立和完善现代冰川平衡线高度与气候统计关系,从传统方法以区域范围内气候因子为参数改造为以冰川范围内气候因子为参数,通过检验认为改造后的公式比较合理.将公式外推到小冰期第二次冰进时的1号冰川,并运用侧碛垄最大高度法确定了小冰期第二次冰进时冰川的平衡线高度,给出了该次冰进时气候条件的半定量推算结果.证明利用山地冰川平衡线高度作为气候变化的代用指标,并且对气候状况进行半定量推断是可行的.

关键词：山地冰川物质平衡线气候变化

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天山乌一号冰川物质平衡特征的统计分析

干旱区地理 2006年第1期29卷 76-80页

作者：鞠远江魏遐刘耕年中国矿业大学资源学院江苏徐州221008 浙江财经学院工商管理学院浙江杭州310012 北京大学环境学院北京100871

利用天山乌鲁木齐河源一号冰川物质平衡的多年观测资料,通过数学统计方法提取主成分,获得影响该冰川物质平衡的主要因素,通过成分矩阵的旋转获得表示冰川物质平衡特征的两个主因子,其中第一主因子为影响冰川物质平衡的常年因子,代表该... 详细信息

利用天山乌鲁木齐河源一号冰川物质平衡的多年观测资料,通过数学统计方法提取主成分,获得影响该冰川物质平衡的主要因素,通过成分矩阵的旋转获得表示冰川物质平衡特征的两个主因子,其中第一主因子为影响冰川物质平衡的常年因子,代表该冰川的多年持续变化方向与趋势,第二主因子为影响冰川物质平衡的年际因子,代表该冰川在平衡年内的物质平衡变化特征。常年因子的持续下降反映了冰川持续后退的现实,年际因子在上世纪80年代中期以后突然强劲上升,实际上是冰川物质平衡水平提高,平衡年内积累量和消融量都增加的表现,清晰地指示了西北地区气候由暖干向暖湿的转型。常年因子是冰川物质平衡变化的主导因子,控制了冰川变化的方向。常年因子具有较好的周期性,以6年周期最为明显,但其形成原因尚不明。年际因子周期性不明显,但可以看出其周期与太阳黑子变化具有相关性,同时受到常年因子的影响。

关键词：一号冰川物质平衡乌鲁木齐河河源主成分分析天山山脉

天山乌鲁木齐河源1号冰川冰蚀基岩面微形态研究

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冰川冻土 2006年第3期28卷 348-354页

作者：刘耕年裴志永陈艺鑫北京大学环境学院北京100871

通过对天山乌鲁木齐河源冰川底床基岩与沉淀物显微结构构造分析,对大陆性山岳冰川冰下过程的认识更加深入.沉积物微观结构和构造特性显示冰川底部存在较大的挤压应力作用,由显微滞碛等现象来看,压应力在微观上的空间分布很不均匀.沉淀... 详细信息

通过对天山乌鲁木齐河源冰川底床基岩与沉淀物显微结构构造分析,对大陆性山岳冰川冰下过程的认识更加深入.沉积物微观结构和构造特性显示冰川底部存在较大的挤压应力作用,由显微滞碛等现象来看,压应力在微观上的空间分布很不均匀.沉淀物中块体碎裂和基岩上冰成裂隙反映,冰川底部冰体对基岩面有巨大的剪切应力作用.滑塌构造说明,冰川底部在微小的区域内压力分布不均匀,局部有重力作用过程存在.沉淀物中块体断裂和同生变形构造的存在说明沉淀物的形成过程为先期沉淀、后期受压.通过对冰川底部各种动力作用特征的阐述及沉淀物结构、构造的成因及特性的总结,认为大陆性山谷冰川底部冰岩界面处存在水膜,且冰川运动亦有滑动性.

关键词：冰下过程显微沉积构造冰蚀基岩面

Small modifications of endo-functionalized cavities lead to large changes in molecular interaction in water

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Science China Chemistry 2025年第1期68卷 369-376页

作者： Song-Meng Wang Hao nian Yan-Fang Wang Li-Shuo Zheng Yu-Tao Zheng Yi-Wei Dong Liping Huang Xiaoping Wang Wei Jiang liu-Pan Yang Department of Chemistry Southern University of Science and Technology School of Chemistry and Pharmaceutical Sciences State Key Laboratory for Chemistry and Molecular Engineering of Medicinal ResourcesGuangxi Normal University School of Pharmaceutical Science Hengyang Medical School University of South China

Studying molecular recognition in aqueous environments is crucial for understanding biological processes. Herein, we present a series of N-doped endo-functionalized anthracene-based cavities by introducing inward-directed pyridine units. The subtle modifications can significantly affect the binding properties of these receptors, which is similar to the mutations in biological systems. Combining theoretical calculations and molecular recognition experiments demonstrated that these “mutations” have an impact on the hydrophobicity and charge distribution of the hosts, consequently significantly influencing molecular *** is crucial for understanding the intricate mechanisms of molecular-level interactions in biological receptors.

关键词： host-guest interaction hydrophobic effect endo-functionalized cavity mutation pyridine

A promising approach for quantifying focal stroke modeling and assessing stroke progression:optical resolution photoacoustic microscopy photothrombosis

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Neural Regeneration Research 2025年第7期20卷 2029-2037页

作者： Xiao Liang Xingping Quan Xiaorui geng Yujing Huang Yonghua Zhao Lei Xi Zhen Yuan Ping Wang Bin liu Faculty of Health Sciences University of MacaoMacao Special Administrative RegionChina Center for Cognitive and Brain Sciences University of MacaoMacao Special Administrative RegionChina Department of Biomedical Engineering Southern University of Science and TechnologyShenzhenGuangdong ProvinceChina State Key Laboratory of Quality Research in Chinese Medicine Institute of Chinese Medical SciencesUniversity of MacaoTaipaMacao Special Administrative RegionChina Department of Emergency Zhujiang HospitalSouthern Medical UniversityGuangzhouGuangdong ProvinceChina

To investigate the mechanisms underlying the onset and progression of ischemic stroke,some methods have been proposed that can simultaneously monitor and create embolisms in the animal cerebral ***,these methods often require complex systems and the effect of age on cerebral embolism has not been adequately studied,although ischemic stroke is strongly *** this study,we propose an optical-resolution photoacoustic microscopy-based visualized photothrombosis methodology to create and monitor ischemic stroke in mice simultaneously using a 532 nm pulsed *** observed the molding process in mice of different ages and presented age-dependent vascular embolism ***,we integrated optical coherence tomography angiography to investigate age-associated trends in cerebrovascular variability following a *** imaging data and quantitative analyses underscore the differential cerebrovascular responses to stroke in mice of different ages,thereby highlighting the technique's potential for evaluating cerebrovascular health and unraveling age-related mechanisms involved in ischemic strokes.

关键词： age-dependent cerebral cortex ischemic stroke mouse model optical coherence tomography angiography photoacoustic microscopy photothrombosis vascular imaging

天山高山冰缘环境中岩石漆的形貌、成分和成因分析

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干旱区地理 2005年第4期28卷 429-434页

作者：傅海荣刘耕年魏遐张小咏北京大学环境学院北京100871

在乌鲁木齐河源海拔3800m以上的空冰斗内发育有黑色富Mn型岩石漆。运用特征元素浓度线扫描对岩石漆表面成分进行了分析,并探寻了岩石漆与下伏基岩在成因上的关系;电镜扫描实验发现典型的葡萄状一半葡萄状一片状的表面微形态序列。实验... 详细信息

在乌鲁木齐河源海拔3800m以上的空冰斗内发育有黑色富Mn型岩石漆。运用特征元素浓度线扫描对岩石漆表面成分进行了分析,并探寻了岩石漆与下伏基岩在成因上的关系;电镜扫描实验发现典型的葡萄状一半葡萄状一片状的表面微形态序列。实验结果显示,岩石漆的物质成分不可能来源于下伏基岩,而是外部来源;粘土矿物在岩石漆形成过程中起到非常重要的作用;岩石漆表面出现蜂窝状的溶蚀孔洞,可能是近年来乌鲁木齐市及河谷后峡地区工业生产造成的酸性污染物传递到河源区对岩石漆化学腐蚀的结果。

关键词：冰缘环境乌鲁木齐河源空冰斗岩石漆