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| 1 | Characteristics of an early Holocene climate and environment from lake sediments in Ebinur region, NW China显示文摘The characteristics of climatic environment in the early Holocene epoch were studied through analyzing environmental proxies from the sediments in the Ebinur Lake--a closed one in the arid region. The pollen assemblage and other geochemical indices showed that, the temperature was somewhat low in the period (8.0-11.5 cal kaBP) as a whole, but in the early period (11.5-10.6 cal kaBP) the temperature was higher, in company with more precipitation. In the conversion period from the early Holocene epoch to the middle Holocene epoch (8.9-8.0 cal kaBP) the climate fluctuated remarkably. Particularly the three layers of peat sediment revealed the strong instability of climate in the early Holocene epoch in the Ebinur region. All information on the development of peat and the experimental data of pollen and stable isotopes implied that, the climatic condition at 8.2, 8.6 and 10.5 cal kaBP was characterized by noticeable cold and humidness, and could be regarded as three cold and humid events in the early Holocene epoch. | WU Jinglu SHEN Ji WANG Sumin JIN Zhangdong YANG Xiangdong | 2005 | Science China Earth Sciences2005，48，2： | 10 |
| 2 | Study on contact fatigue of a wind turbine gear pair considering surface roughness显示文摘Contact fatigue issues become more and more crucial in gear industry as they significantly affect the reliability and service life of associated mechanical systems such as wind turbine gearboxes.The contact fatigue behavior is mostly determined by the mechanical properties of materials and stress fields near the contact area,which is further influenced by the lubrication and surface roughness due to pressure fluctuations.In this study,a numerical model incorporating the lubrication state,tooth surface roughness,residual stress,and mechanical properties of the material is developed to determine the contact fatigue behavior of a megawatt level wind turbine carburized gear.The variations of the hardness and residual stress along the depth were characterized by the Vickers hardness measurement and X-ray diffraction test,respectively.The elastohydrodynamic lubrication theory was applied to predict the contact pressure distribution,highlighting the influence of the surface roughness that stemed from the original measurement through an optical profiler.The stress histories of the studied material points during a complete contact loading cycle were fast calculated using the discreteconcrete fast Fourier transformation(DC-FFT)method.Modified Dang Van diagrams under different working conditions were determined to estimate the contact fatigue failure risk.The effect of the root mean square(RMS)value of the surface roughness on the failure risk at critical material points were discussed in detail.Results revealed that the surface roughness significantly increases the contact fatigue failure risk within a shallow area,and the maximum risk appears near the surface. | Heli LIU Huaiju LIU Caichao ZHU Zhangdong SUN Houyi BAI | 2020 | Friction2020，8，3： | 7 |
| 3 | Mineralogy of the otoliths of naked carp Gymnocypris przewalskii (Kessler) from Lake Qinghai and its Sr/Ca potential implications for migratory pattern显示文摘Otoliths are biogenic carbonate minerals whose microstructure and microchemistry have been used for age determination, stock identification, life history and environmental tracing. Using X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy, we have determined the mineral types and crystalline characteristics of three pairs of otoliths from naked carp Gymnocypris przewalskii, the predominant fish in Lake Qinghai. The results indicate that the mineral of both lapillus and sagitta of the naked carp is aragonite, and that of asteriscus is vaterite. The aragonite of lapillus has prefect crystallization. Given the shape of lapillus and the sensitivity of its aragonite to water chemistry, lapillus was used to analyze temporal Sr/Ca ratios along the maximal growth axis by an electron probe microanalyzer (EPMA). Consistent variations of Sr/Ca ratios with a range of 1.0×10 3-5.0×10 3 on the long and short radii indicate that Sr/Ca ratios of lapillus potentially respond to the chemical compositions of the host waters during the period of the naked carp's growth and migration. Discontinuous (dark) zones of lapillus were formed during fall and winter when the naked carp grows slowly in Lake Qinghai, resulting in similar low Sr/Ca ratios to lake water, whereas incremental zones with higher Sr/Ca ratios respond to its migratory river waters during spring and summer. Various Sr/Ca ratios of incremental zones suggest that the migratory pattern of the naked carp may be much more flexible, rather than in a single river. Therefore, high-resolution otolith microchemistry of the naked carp can be used to trace its migratory behavior, which is of significance for determining its migratory pattern and life history of this precious species inhabiting the Tibetan Plateau. | ZHOU Ling JIN ZhangDong LI FuChun | 2012 | Science China Earth Sciences2012，55，6： | 6 |
| 4 | Concentrations and contamination trends of heavy metals in the sediment cores of Taihu Lake,East China,and their relationship with historical eutrophication显示文摘To assess the contamination trends and potential bio-availability of sediment-bound heavy metals,concentrations of heavy metals in acid-leaching fraction and in bulk sediments from the two typical bays(the Meiliang Bay and Xuhu Bay) of the Taihu Lake,East China,were studied.Pb and Zn showed elevated concentrations in the sediments from both areas,although sedimentation history and degree of pollution are different between the two bays.In the Meiliang Bay,both Pb and Zn pollutions started in the late 1970's,the same time as the beginning of eutrophication of the lake,while the in the Xuhu Bay the metal contamination started since recent 10 years.The concentrations of acid-leachable Pb in the sediments from the Meiliang Bay are correlated with the historical eutrophication process.Before the eutrophication and heavy metal pollution,the chemical properties of the lake sediments were the same as the source compositions of the Xiashu loess.Both Pb and Zn in the sediments mainly occur in leachable forms by nitric or hydrochloric acid,whilst most of Cu is in residual fraction.The results indicate that both Pb and Zn may have higher mobility and bioavailability in water and biology than Cu. | JIN Zhangdong CHENG Hangxin CHEN Li LI Xiangdong ZHU Guangwei ZHUANG Guangmin QIAN Na | 2010 | Chinese Journal Of Geochemistry2010，29，1： | 4 |
| 5 | Fingerprinting hydrothermal fluids in porphyry Cu deposits using K and Mg isotopes显示文摘In this study, we performed an integrated investigation of K and Mg isotopes in hydrothermally altered rocks from the giant Dexing porphyry Cu deposit in China. Both the altered porphyry intrusion and the surrounding wall rocks exhibit large variations in K and Mg isotope compositions, with δ41K values ranging between-1.02‰ and 0.38‰, and δ26Mg values ranging between-0.49‰ and 0.32‰. The δ41K and δ26Mg values of the majority of altered samples are higher than the isotopic baseline values for upper continental crust. We attribute the general increase in δ41 K and δ26Mg in altered rocks to hydrothermal alteration,which caused preferential incorporation of heavy K and Mg isotopes in alteration products, particularly phyllosilicates. However,a few altered samples show anomalously low δ41K and δ26Mg values. The δ41K and δ26Mg values do not correlate with K and Mg concentrations, or mineralogy of altered samples. The variable K-Mg isotope data likely reflect fluids of different physicalchemical properties, or different isotopic compositions. Based on the combined K-Mg isotope data, at least three groups of hydrothermal fluids are distinguished from the Dexing porphyry deposit. Therefore, K-Mg isotopes are potentially a novel tracer for fingerprinting fluids in complex hydrothermal systems. | Weiqiang LI Shugao ZHAO Xiaomin WANG Shilei LI Guoguang WANG Tao YANG Zhangdong JIN | 2020 | Science China Earth Sciences2020，63，1： | 4 |
| 6 | Relationship between the temperature and the acoustic nonlinearity parameter in biological tissues显示文摘Recently with the rapid development of the high-intensity focused ultrasound (HIFU) in biomedical ul- trasound, much attention has been paid to the noninvasive temperature estimation in biological tissue in order to de- termine the region and degree of the ultrasound-induced lesions. In ultrasound hyperthermal therapy it is highly de- sirable to study the real-time noninvasive monitoring of temperature distribution in biological tissue. In this paper, the relationship between the nonlinearity parameter B/A and the temperature in biological tissue is studied and compared with the theoretical model as well as the experimental results from the thermocouple. Results indicated that B/A could be used as an effective tool to monitor the temperature distribu- tion in biological media. | LUYing LIUXiaozhou GONGXiufen ZHANGDong | 2004 | Chinese Science Bulletin2004，49，22： | 3 |
| 7 | Stratigraphy and otolith microchemistry of the naked carp Gymnocypris przewalskii(Kessler) and their indication for water level of Lake Qinghai during the Ming Dynasty of China显示文摘耳石是在 teleost 鱼的内耳的源於生物的碳酸盐矿物质,其作文能记录周围的水环境的物理、化学的条件,由单个鱼住在。在在鸟岛附近取样的裸体鲤鱼的这研究,鱼骨和耳石,近海金海湖,为矿物学和 microchemical 作文过时、分析。现代耳石把古老的耳石的 microchemical 作文与那些作比较,当湖从高湖水平缩小了时,我们断定古老的裸体鲤鱼住在形成的一个寡妇湖,由与AMS-结合--<啜class=“ a-plus-plus ”> 14 鱼骨和耳石,地层学和样品地点的包围地形学的 C 年龄。AMS---< 啜 class= “ a-plus-plus ” > 14 古老的鱼骨和耳石的 C 标明日期结果证明这些裸体鲤鱼以前从 680 ~ 300 年生活了,即在中国的明王朝期间。X 光检查衍射(XRD ) 模式证明古老的火山砾由纯霰石组成,与现代的相同,显示火山砾 didnt 的矿物质在很长时间埋葬以后变化并且古老的火山砾此后对比较分析合适。Microchemical 结果两个都显示出那 Mg/Ca 的比率((70.12 汵牡爠獥牥潶物 ? 潣汵?敤敶潬 | WANG YuJiao JIN ZhangDong ZHOU Ling LI FuChun ZHANG Fei CHEN LiuMei QIU XinNing QI RuGui | 2014 | Science China Earth Sciences2014，57，10： | 3 |
| 8 | Sm-Nd isotope study and dating on Honguleleng ophiolite in Xinjiang, China显示文摘A study of the Sm-Nd isotope composition of Honguleleng ophiolite in Xinjiang, China, isochron age ((626±25)Ma),εNd(t) = 8.40,and its model age (TNdDM) in the range of 1 180-1 208 Ma, indicates that the ophiolite was formed in the late stage of the Upper Sinian. In combination with its facies association, petrochemistry, REE patterns, trace elements | Zhangdong Jin Jianhua Huang Fuchun Li | 1999 | Chinese Science Bulletin1999，44，20： | 2 |
| 9 | The role of earthquake-induced landslides in erosion and weathering from active mountain ranges:Progress and perspectives显示文摘Earthquakes play a fundamental role in the evolution of Earth’s topography through co-seismic uplift and subsidence,as well as erosion through widespread landslides induced by ground motion.Earthquake-induced landslides can result in exceptional increases in the transfer of mass from landscapes,supplying sediment to rivers where impacts can last for decades or longer.Landslides can also erode vegetation and soils,in addition to exposing freshly ground rock mass,which can both result in regionally significant carbon transfers.Recent work has sought to quantify the fluxes,rates,and temporal patterns of the impacts on earth surface processes generated by these tectonic events.In this review,we focus on the impacts of earthquake-induced landslides on erosion and sediment flux,river water chemistry,and carbon export through the lens of the well-studied 2008 Wenchuan earthquake.We then discuss these themes in the context of works from the 1999 Taiwan Chi-Chi earthquake,2015 Nepalese Gorkha earthquake,and New Zealand historical earthquakes,altogether highlighting an important role of earthquake-induced landslides in erosion and weathering along tectonically active mountain ranges.We suggest that more monitoring,geochemical tracing,paleo-records,and/or modelling studies are needed to compare the processes and fluxes of catchment erosion and weathering before and after earthquake events,which will help to deepen our understanding not only of the impacts of earthquake-induced landslides on earth surface processes,but also the linkage among high magnitude events,continental erosion and weathering,and the long-term global carbon cycle. | Zhangdong JIN Robert G.HILTON AJoshua WEST Gen K.LI Fei ZHANG Jin WANG Gaojun LI Xuanmei FAN Meng-Long HSIEH | 2021 | Science China Earth Sciences2021，64，12： | 2 |
| 10 | Upper embeddability,edge independence number and girth显示文摘Combined with the edge-connectivity, this paper investigates the relationship between the edge independence number and upper embeddability. And we obtain the following result: Let G be a k-edge-connected graph with girth g. If α '(G)≤((k-1)2+2) [g/2]+(1-(-1)n)/2((k-1)(k-2)+1)-1,where k =1, 2, 3, and α (G) denotes the edge independence number of G, then G is upper embeddable and the upper bound is best possible. And it has generalized the relative results. | OUYANG ZhangDong TANG Ling HUANG YuanQiu | 2009 | Science China Mathematics2009，52，9： | 2 |
| 11 | CAVITATION INCEPTION WITNESSED BY SOUND PRESSURE LEVEL IN MODEL TEST AND PROTOTYPE OBSERVATION显示文摘The paper concerns with the relationship between cavitation inception and Sound Pressure Level (SPL). A case study for the Xiaolangdi Hydro-project was taken as a typical example, which demonstrated the standard criterion of SPL indicating cavitation inception. Cavitation inception of an orifice plate used for energy dissipation in a tunnel spillway was witnessed and verified both in model test and prototype observation. A design criterion was proposed for a cavitation-free hydraulic structure which can be served as a reference for designers as well as researchers. Consequently, scale effects were discussed with an aim at suggesting an appropriate factor of safety in design. | ZHANGDong LIUZhi-ping JINTai-lai XIANGYa-ping | 2004 | Journal of Hydrodynamics2004，16，2： | 2 |
| 12 | Two recursive inequalities for crossing numbers of graphs显示文摘在这份报纸,为穿过图的数字的二递归的不平等被使用基本的数给方法。作为他们的应用,十字路口 K 1,3, n 和 K 数 4, n \ e 分别地被决定。 | Zhangdong OUYANG Jing WANG Yuanqiu HUANG | 2017 | Frontiers of Mathematics in China2017，12，3： | 2 |
| 13 | Rosiglitazone improves post-infarction left ventricular contractile function in rats显示文摘Peroxisome proliferator-activated receptor-γ (PPAR-γ) is a transcription factor belonging to the nuclear receptor superfamily that binds to specific response elements. Rosiglitazone, promotes insulin sensitization and is a synthetic agonist ligand of PPAR-γ. 1 In recent years, a number of studies have shown that triglitazone and piglitazone, which are chemically related to rosiglitazone, can attenuate postinfarction left ventricular remodeling, 2 but there are few studies assessing whether rosiglitazone similarly improves postinfarction left ventricular remodeling and cardiac function. Therefore, the purpose of this study was to determine whether rosiglitazone can improve left ventricular remodeling and cardiac function in a rat model of post-myocardial infarction (MI), and to explore potential underlying mechanisms. | LiBao MAYe-xin XIEJun YANGBin LIZhi WANGHui-zhen ZHANGDong NIUBo | 2005 | Chinese Medical Journal2005，，12： | 2 |
| 14 | Role of late glacial to mid-Holocene climate in catchment weathering in the central Tibetan Plateau显示文摘 | Jin Zhangdong Wu Yanhong Zhang Xiaohui | 2005 | Quaternary Research2005，63，： | 1 |
| 15 | Criss-Cross Attentional Siamese Networks for Object Tracking显示文摘Visual object tracking is a hot topic in recent years.In the meanwhile,Siamese networks have attracted extensive attention in this field because of its balanced precision and speed.However,most of the Siamese network methods can only distinguish foreground from the non-semantic background.The fine-tuning and retraining of fully-convolutional Siamese networks for object tracking(SiamFC)can achieve higher precision under interferences,but the tracking accuracy is still not ideal,especially in the environment with more target interferences,dim light,and shadows.In this paper,we propose crisscross attentional Siamese networks for object tracking(SiamCC).To solve the imbalance between foreground and non-semantic background,we use the feature enhancement module of criss-cross attention to greatly improve the accuracy of video object tracking in dim light and shadow environments.Experimental results show that the maximum running speed of SiamCC in the object tracking benchmark dataset is 90 frames/second.In terms of detection accuracy,the accuracy of shadow sequences is greatly improved,especially the accuracy score of sequence HUMAN8 is improved from 0.09 to 0.89 compared with the original SiamFC,and the success rate score is improved from 0.07 to 0.55. | Zhangdong Wang Jiaohua Qin Xuyu Xiang Yun Tan Neal N.Xiong | 2022 | Computers, Materials & Continua2022，，11： | 1 |
| 16 | Chemical weathering since the little ice age recorded in lake sediments: a high-resolution proxy of past climate 显示文摘 | Jin Zhangdong Wang Sumin Shen Ji | 2001 | Earth Surface Processes and Landforms2001，26，7： | 1 |
| 17 | Holoeene climate development on the central Tibetan Plateau: A sedimentary record from Cuoe Lake 显示文摘 | Wu Yanhong Andreas Lticke Jin Zhangdong | 2006 | Palaeogeography Palaeoclimatology Palaeoecology2006，234，24： | 1 |
| 18 | Copolymerization of ε-caprolactone with (3S)-3- morpholine-2,5-dione and the ^13 C-NMR sequence analysis of the copolymer 显示文摘 | Guo Dong Wang Zhangdong Feng Xinde | 1998 | Macromolecules1998，31，12： | 1 |
| 19 | Role of late glacial to mid-Holocene climate in catchment weathering in the central Tibetan Plateau显示文摘 | Jin Zhangdong Wu Yanhong Zhang Xiaohui | 2005 | Quaternary Research2005，63，： | 1 |
| 20 | The observation of the treatment effect of 102 pulpitis with mummification 显示文摘 | ZhaoZhi - qing ZhangDong - qing | 2007 | The Journal of Dentist- ry - Endodontics Periodontitis2007，22，12： | 1 |
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