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Rising utilization of stable isotopes in tree rings for climate change and forest ecology

Journal of Forestry Research 2024年第1期35卷 103-116页

作者： Ru Huang Chenxi Xu Jussi Grießinger Xiaoyu Feng haifeng zhu Achim Bräuning National Institute of Natural Hazards Beijing 100085People’s Republic of China Key Laboratory of Cenozoic Geology and Environment Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029People’s Republic of China CAS Center for Excellence in Life and Paleoenvironment Beijing 100044People’s Republic of China Institute of Geography Friedrich-Alexander-University of Erlangen-Nuremberg91058 ErlangenGermany State Key Laboratory of Tibetan Plateau Earth System Environment and Resources(TPESER)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101People’s Republic of China University of Chinese Academy of Sciences Beijing 100049People’s Republic of China

Analyses of stable isotopes(C,O,H)in tree rings are increasingly important cross-disciplinary programs.The rapid development in this field documented in an increasing number of publications requires a comprehensive review.This study includes a bibliometric analysis-based review to better understand research trends in tree ring stable isotope research.Overall,1475 publications were selected from the Web of Science Core Collection for 1974-2023.The findings are that:(1)numbers of annual publications and citations increased since 1974.From 1974 to 1980,there were around two relevant publications per year.However,from 2020 to 2022,this rose sharply to 109 publications per year.Likewise,average article citations were less than four per year before 1990,but were around four per article per year after 2000;(2)the major subjects using tree ring stable isotopes include forestry,geosciences,and environmental sciences,contributing to 42.5%of the total during 1974-2023;(3)the top three most productive institutions are the Chinese Academy of Sciences(423),the Swiss Federal Institute for Forest,Snow and Landscape Research(227),and the University of Arizona(204).These achievements result from strong collaborations;(4)review papers,for example,(Dawson et al.,Annu Rev Ecol Syst 33:507-559,2002)and(McCarroll and Loader,Quat Sci Rev 23:771-801,2004),are among the most cited,with more than 1000 citations;(5)tree ring stable isotope studies mainly focus on climatology and ecology,with atmospheric CO_(2) one of the most popular topics.Since 2010,precipitation and drought have received increasing attention.Based on this analysis,the research stages,key findings,debated issues,limitations and direc-tions for future research are summarized.This study serves as an important attempt to understand the progress on the use of stable isotopes in tree rings,providing scientific guid-ance for young researchers in this field.

关键词： Tree rings Stable isotopes Web of Science Bibliometric

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Optimization of the Swept Volume Ratio between the Compressor and the Active Displacer in an Efficient 20 K Thermal-Coupled Two-Stage Pulse Tube Cryocooler

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Journal of Thermal Science 2023年第6期32卷 2155-2165页

作者： YIN Wang LIU Shaoshuai SONG Jiantang WU Wenting HUI Hejun JIANG Zhenhua LI Nanxi zhu haifeng WU Yinong Shanghai Institute of Technical Physics Chinese Academy of SciencesShanghai200083China University of Chinese Academy of Sciences Beijing100049China Nantong Academy of Intelligent Sensing Nantong226000China

As an important component of the stirling-type pulse tube cryocooler(SPTC),an efficient phase shifter can significantly improve the cooling capacity.Compared to the common phase shifter,the active warm displacer(AWD)has a wider phase adjustment range and therefore can obtain a better phase relationship easily.Based on a two-stage thermal-coupled SPTC operating in the 20 K range,this paper studied the influence of the swept volume ratio between the compressor and displacer.The research found that the swept volume ratio changes the cooling capacity and efficiency of the cryocooler mainly by changing the phase difference between the pressure wave and the volume flow at the cold end.It was found from the results of the simulation and experiments that there is an optimal displacement of the displacer(Xd)of 2.5 mm and an optimal phase angle of 15°to obtain the highest cooling efficiency while the displacement of the compressor is constant.The cooling capacity at 20 K is 1.3 W while the input electrical power of the second stage compressor is 202 W,which indicates an overall relative Carnot efficiency(rCOP)of 0.055 in terms of input electrical power.In addition,due to the reasonable setting of precooling temperature and capacity,the swept volume ratio and phase at the maximum cooling capacity and maximum efficiency are consistent in this study.The research improves the understanding of phase shifters and has guiding significance for the optimization of the SPTC working below 20 K.

关键词： two-stage pulse tube cryocooler phase shifter active warm displacer cooling capacity 20 K

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Hydrophobic-surface of copper from converter slag in the flotation system

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International Journal of Mining Science and Technology 2013年第4期23卷 599-603页

作者： Huang Hongjun zhu haifeng Hu Yuehua School of Mineral Processing and Bioengineering Central South University

The converter slag from a smeltery in Daye contains 2.01% copper.The floatability of copper has a significant influence on the flotation of converter slag.Flotation tests,contact angle tests and FTIR were conducted to assess the influences of pH and different flotation concentrators on its hydrophobic process,mechanism and flotation.The results show that since chemisorptions are formed on the surface,hydrophobicity of copper is highly enhanced by xanthate,butylamine dithiophosphate and Z-200.The hydrophobic-surface of copper becomes worse with low recovery in strong acid and alkali situation.When pH value is 10,butylamine dithiophosphate and butyl xanthate are used as the mixed-collector,the grade of copper is 40.01%and that of tailings is 0.37%.

关键词： Converter slag Copper Flotation Hydrophobic

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Tree ring-dated fluctuation history of Midui glacier since the Little Ice Age in the southeastern Tibetan Plateau

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Science China Earth Sciences 2012年第3期55卷 521-529页

作者： XU Peng zhu haifeng SHAO XueMei YIN ZhiYong Institute of Geographic Sciences and Natural Resources Research Chinese Academy of SciencesBeijing 100101China Institute of Tibetan Plateau Research Chinese Academy of SciencesBeijing 100085China Department of Marine Science and Environmental Studies University of San DiegoSan DiegoCA 92110USA Graduate University of Chinese Academy of Sciences Beijing 100049China

Fluctuation history of Midui glacier in the southeastern Tibet since the Little Ice Age(LIA) was reconstructed by the dating of lateral and terminal moraines using tree rings.Four conversions of glacier advance/stabilization to retreat were identified at around 1767,1875,1924 and 1964.The glacier reached its LIA maximum position at 1767.The fluctuations are consistent with those of other glaciers from the Tibetan Plateau,the Rockies and the Alps,suggesting high spatial coherency of glacier fluctuations in the Northern Hemisphere.Comparison with the summer temperature reconstruction in the southeastern Tibetan Plateau indicated that the Midui glacier fluctuation may be related to temperature variation on the centennial timescale.On the decadal scale,the fluctuation could correspond to cold/warm variation with an 8-year lag on average.

关键词：青藏高原东南部冰川波动树木年轮小冰期历史西藏东南部阿尔卑斯山空间一致性

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Identification of tissue types and boundaries with a fiber optic force sensor

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Science China(Information Sciences) 2014年第12期57卷 58-64页

作者： YANG TangWen zhu haifeng HAN JianDa ZHAO XinGang XU WeiLiang Institute of Information Science Beijing Jiaotong University State Key Laboratory of Robotics Shenyang Institute of Automation Chinese Academy of Sciences Department of Mechanical Engineering University of Auckland

The absence of tactile force information at the tip of a medical instrument makes precise minimally invasive surgery difficult and is prone to resulting in serious outcomes.In this paper,a fiber optic force sensor is fabricated based on Fabry-P′erot interferometry and integrated with a puncture needle.The force sensor is attached to the needle tip,where interactive force arises as it inserts into soft tissue.Needle insertion experiments have been conducted on ex vivo swine liver and belly with the calibrated force sensor.Using wavelet transform method,the acquired force data are analyzed and used to identify layered tissue types and boundaries.We found that the force amplitudes are not always identical,but the patterns of forces are almost the same,which enables us to identify layered tissues and to realize a safe needle insertion procedure under robot control.

关键词： fiber optic force sensor needle puncture layered tissue identification of tissue types and boundaries wavelet transform

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May-June mean maximum temperature change during 1360-2005 as reconstructed by tree rings of Sabina Tibetica in Zaduo,Qinghai Province

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Chinese Science Bulletin 2010年第26期55卷 3023-3029页

作者： SHI XingHe QIN NingSheng zhu haifeng SHAO XueMei WANG QingChun zhu XiDe Institute of Plateau Meteorology China Meteorological Administration Chengdu 610072 China Climate Date Center ofQinghai Qinghai Meteorological Bureau Xining 810001 China Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China

Based on tree-ring samples collected from Zaduo area in southern Qinghai Province, a 646-year ring-width series was established. Using response function, correlation function and partial correlation analysis we found that the ring-width series is sensitive most to May and June mean maximum air temperature at Zaduo meteorological stations and the correlation is significantly negative. Therefore, May-June mean maximum air temperature in Zaduo area since 1360 is reconstructed using this ring-width series. The regression equation was cross-validated in the calibration period of 1961-2005. The calibration equation can explain 59.8% of the total variance. Since high temperature could reinforce evapotranspiration and result in water stress, the high values are more reliable than the low values in the reconstructed series. By further analyzing upon the reconstructed series, it shows that on the in-ter-annual scale there are 6 periods with higher temperature: 1438-1455, 1572-1612, 1684-1700, 1730-1754, 1812-1829 and 1853-1886; while there are 5 periods with lower temperature: 1547-1571, 1701-1729, 1755-1777, 1830-1852 and 1887-1910. There is no significant rising of temperature in recent 50 years. By comparison with the rings-width series nearby which are also sensitive to the mean maximum air temperature and the mean maximum temperature reconstruction by ring-widths, it is found that the variation of inter-annual scale is fairly common in the region.

关键词：树木年轮三江源自然保护区温度变化月平均青海省平均最高气温年轮宽度年际尺度

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论历代治黄方略中的“中国智慧”

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华北水利水电大学学报（社会科学版） 2024年第1期40卷 1-9页

作者：朱海风华北水利水电大学水文化研究中心河南郑州450046

回顾历代疏水导水、防水御水、束水攻沙、谐水让水、调水调沙、协同治理和综合创新等黄河治理方略,总结概括其深邃的时代价值,提炼彰显其启迪现在及将来的“中国智慧”,包括“疏导”与“堵塞”辩证实施是中国治水成功的基本理路、“利... 详细信息

回顾历代疏水导水、防水御水、束水攻沙、谐水让水、调水调沙、协同治理和综合创新等黄河治理方略,总结概括其深邃的时代价值,提炼彰显其启迪现在及将来的“中国智慧”,包括“疏导”与“堵塞”辩证实施是中国治水成功的基本理路、“利人”与“利水”双向互动是中国治水成功的根本原因、“治水”与“治人”两手发力是中国治水成功的重要法宝、“治水”与“治国”融通联动是中国治水成功的切实保障等,对于进一步增强文化自信,彰显中华先进水文化成果,建设中华民族现代文明,具有重要的理论价值和现实意义。

关键词：治黄方略中国智慧黄河良治

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Automatic extraction of foreground objects from Mars images

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Geo-Spatial Information Science 2012年第1期15卷 17-25页

作者： WANG Shuliang LIU Chang WU Shangru NIE Qianqian WANG Yongtao ZENG Shi zhu haifeng International School of Software Wuhan University129 Luoyu RoadWuhan 430079China Key Laboratory of Data Mining and Knowledge Engineering Inner Mongolia Autonomous RegionInner Mongolia UniversityHohhot 010021China Department of Geography East Michigan UniversityYpsilantiMI 48197USA

A novel method is proposed to automatically extract foreground objects from Martian surface images.The characteristics of Mars images are distinct,e.***.uneven illumination,low contrast between foreground and background,much noise in the background,and foreground objects with irregular shapes.In the context of these characteristics,an image is divided into foreground objects and background information.Homomorphism filtering is first applied to rectify brightness.Then,wavelet transformation enhances contrast and denoises the image.Third,edge detection and active contour are combined to extract contours regardless of the shape of the image.Experimental results show that the method can extract foreground objects from Mars images automatically and accurately,and has many potential applications.

关键词： automatic object extraction Mars images homomorphic filtering wavelet transformation active contour edge detection

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Millennial temperature reconstruction based on tree-ring widths of Qilian juniper from Wulan,Qinghai Province,China

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Chinese Science Bulletin 2008年第24期53卷 3914-3920页

作者： zhu haifeng ZHENG YongHong SHAO XueMei LIU XiaoHong XU Yan LIANG ErYuan Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 100085 China State Key Laboratory of Cryospheric Sciences Cold and Arid Regions Environment and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China Graduate School of the Chinese Academy of Sciences Beijing 100049 China

The climate of the past 1000 years is an important context for evaluating the recent climate warming.However,there are few 1000-year-long climate reconstructions with annual resolution in the Qing-hai-Tibet Plateau.In this paper,a dendroclimatic analysis was conducted for the radial growth of Qilian juniper from the upper forest limit in Wulan,Qinghai Province.The results of correlation analysis between the tree-ring widths and the climate variables indicate that the growth of junipers at the upper forest limit is mainly limited by low temperatures of September,November and February of the pregrowth season,and July of the current growth season.There is no significant correlation between the tree-ring widths and precipitation.A mean temperature from the previous year's September to the current year's April was reconstructed for the Wulan area since A.D.1000.The reconstruction can explain 40.8% of the instrumental variance in the calibration period(1856―2002).The reconstruction shows that the 20th century is the warmest 100 years,and the 1990s is the warmest decade during the past 1000 years,while the coldest 100 years and decade occur at 1600―1699 and 1642―1651,respectively.The variations are verified well by the temperature reconstruction of the middle Qilian Mountain(QL) and the total organic carbon(TOC) in the Qinghai Lake sediments.The comparison of our reconstruction with the annual temperature reconstruction of extra-tropical Northern Hemisphere suggests that the climate of Wulan during the Medieval Warm Period is of obvious regional specialty,but there was a good response to the climate of hemispheric scales during the recent 400 years.

关键词：西藏高原盆地桧属植物年轮温度记录

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硫辛酸注射液联合胰激肽原酶肠溶片对DPN的临床疗效及生存质量的影响

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糖尿病新世界 2024年第1期27卷 174-178页

作者：王莉朱海峰濉溪县中医医院内分泌科安徽淮北235100

目的探讨硫辛酸注射液联合胰激肽原酶肠溶片对2型糖尿病周围神经病变(Diabetic Peripheral Neuropathy, DPN)患者的临床疗效、生存质量及安全性的影响。方法选取2021年2月—2022年4月濉溪县中医医院60名DPN患者作为研究对象。通过随... 详细信息

目的探讨硫辛酸注射液联合胰激肽原酶肠溶片对2型糖尿病周围神经病变(Diabetic Peripheral Neuropathy, DPN)患者的临床疗效、生存质量及安全性的影响。方法选取2021年2月—2022年4月濉溪县中医医院60名DPN患者作为研究对象。通过随机数表法分为两组,每组30例。对照组采用常规治疗,观察组在对照组基础上加用硫辛酸注射液和胰激肽原酶肠溶片治疗。比较两组患者的神经病变评分、神经电生理指标、生存质量评分、安全性指标和不良反应发生率。结果治疗后,观察组神经病变评分(6.2±0.9)分低于对照组(7.6±1.1)分,差异有统计学意义(t=5.438,P0.05)。结论硫辛酸注射液联合胰激肽原酶肠溶片对DPN患者有良好的临床疗效,能够改善神经功能、改善神经电生理指标、提高生存质量,且安全性高。

关键词：硫辛酸注射液胰激肽原酶肠溶片 2型糖尿病周围神经病变临床疗效

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