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Climate-growth relationships of Pinus tabuliformis along an altitudinal gradient on Baiyunshan Mountain,Central China

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Journal of Forestry Research 2024年第1期35卷 202-212页

作者： Xiaoxu Wei Jianfeng peng Jinbao li Jinkuan li Meng peng Xuan li Yameng liu Jiaxin li College of Geography and Environmental Science Henan UniversityKaifeng 475004People’s Republic of China Key Laboratory of Earth System Observation and Simulation of He’nan Province Kaifeng 475004People’s Republic of China Department of Geography University of Hong KongPokfulamHong Kong SARPeople’s Republic of China HKU Shenzhen Institute of Research and Innovation Shenzhen 518057People’s Republic of China

A set of standard chronologies for tree-ring width(TRW),earlywood width(EWW)and latewood width(LWW)in Pinus tabuliformis *** an altitudi-nal gradient(1450,1400,and 1350 m a.s.l.)on Baiyunshan Mountain,Central China to analyze the effect of varying temperature and precipitation on growth along the *** analyses showed that at all three altitudes and the TRW and EWW chronologies generally had signifi-cant negative correlations with mean and maximum tem-peratures in the current April and May and with minimum temperatures in the prior July and August,but significant positive correlations with precipitation in the current *** were generally significantly negative between LWW chronologies and all temperatures in the prior July and August,indicating that the prior summer temperature had a strong lag effect on the growth of *** that increased with *** correlation with the standard-ized precipitation evapotranspiration index(SPEI)confirmed that wet conditions in the current May promoted growth of TR and EW at all *** altitudinal differences were also found;at 1400 m,there were significant positive correlations between EWW chronologies and SPEI in the current April and significant negative correlations between LWW chronologies and SPEI in the current September,but these correlations were not significant at 1450 *** 1350 m,there were also significant negative correlations between the TRW and the EWW chronologies and SPEI in the prior October and the current July and between LWW chronology and SPEI in the current August,but these cor-relations were not significant at 1400 *** correlation results showed a stable response of EWW in relation to the SPEI in the current May at all three altitudes and of LWW to maximum temperature in the prior July-August at 1400 m from 2002 to *** EWW chronology at 1400 m and the LWW chronology at 1450 m were identified as more suitable for climate reconstruction.T

关键词： Tree rings Climate response Altitudinal gradient Baiyunshan Mountain Pinus tabuliformis Carr

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TiO_(2) nanofiber-supported copper nanoparticle catalysts for highly efficient methane conversion to C1 oxygenates under mild conditions

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Nano Research 2024年第5期17卷 3844-3852页

作者： Wencui li yu Ren Zean Xie Yipeng Wang Hang Zhang Dianxiang peng Hengfang Shen Hongfei Shi Jiaxin Cai peng Wang Tongxin Zhang Zhen Zhao State Key Laboratory of Heavy Oil Processing China University of Petroleum(Beijing)Beijing 102249China Institute of Catalysis for Energy and Environment College of Chemistry&Chemical EngineeringShenyang Normal UniversityShenyang 110034China Institute of Petrochemical Technology Jilin Institute of Chemical TechnologyJilin 132022China

The selective oxidation of methane under mild conditions remains the“Holy Grail of Catalysis”.The key to activating methane and inhibiting over-oxidation of target oxygenates lies in designing active *** nanoparticles were loaded onto TiO_(2) nanofibers using the photo-deposition *** resulting catalysts were found to effectively convert methane into C1 oxygenated products under mild *** with previously reported catalysts,it delivers a superior performance of up to 2510.7 mmol·g_(Cu)^(-1)·h^(-1) productivity with a selectivity of around 100%at 80℃for 5 *** characterizations and density functional theory(DFT)calculations indicate that TiO_(2) in the mixed phase of anatase and rutile significantly increases the Cu^(+)/CuO ratio of the supported Cu species,and this ratio is linearly related to the formation rate of oxygen-containing *** CuI site promotes the generation of active O species from H_(2)O_(2) dissociation on Cu_(2)O(111).These active O species reduce the energy barrier for breaking the C-H bond of CH_(4),thus boosting the catalytic *** methane conversion mechanism was proposed as a methyl radical pathway to form CH_(3)OH and CH_(3)OOH,and then the generated CH_(3)OH is further oxidized to HOCH_(2)OOH.

关键词： TiO_(2)nanofiber copper nanoparticles photo-deposition method methane oxidation C1 oxygenates

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Unsupervised construction of health indicator for rotating machinery via multi-criterion feature selection and attentive variational autoencoder

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Science China(Technological Sciences) 2024年第5期67卷 1524-1537页

作者： li Xinyu CHENG ChangMing peng ZhiKe State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong UniversityShanghai200240China School of Mechanical Engineering Ningxia UniversityYinchuan750021China

Health indicator(HI)construction is a crucial task in degradation evaluation and facilitates the prognostic and health management(PHM)of rotating *** interference from artificial labeling,the HI construction approaches in an unsupervised manner have attracted substantial ***,current unsupervised methods generally struggle with two problems:(1)ignorance of both redundancy between features and global variability of features during the feature selection process;(2)inadequate utilization of information from different sampling *** tackle these problems,this work develops a novel unsupervised approach for HI construction that integrates multi-criterion feature selection and the Attentive Variational Autoencoder(Attentive VAE).Explicitly,a multi-criterion feature selection(Mc FS)algorithm together with an elaborately designed metric is proposed to determine a superior feature subset,considering the relevance,the redundancy,and the global variability of features ***,for the adequate utilization of the information from distinct sampling moments,a deep learning model named Attentive VAE is *** Attentive VAE is solely fed with the selected features in the health state for model training and the HI is derived through the reconstruction error to reveal the degradation degree of *** case studies based on genuine experimental datasets are involved to quantitatively evaluate the superiority of the developed approach,demonstrating its superiority over other unsupervised methods for characterizing degradation *** effectiveness of both the Mc FS algorithm and the Attentive VAE is verified by ablation experiments,respectively.

关键词： health indicator(HI) unsupervised learning multi-criterion feature selection global variability attention mechanism

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Exploring the Predominant Factors Influencing the Oxygen Reduction Performance of PtCo/C Catalysts

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Chemical Research in Chinese Universities 2024年第4期40卷 753-760页

作者： li Jinrong yu Xianghui SUN Qi peng Yong CAO Shuang HOU Chun-Chao XU Qiang College of Chemistry and Chemical Engineering Institute for Sustainable Energy and ResourcesQingdao UniversityQingdao266071P.R.China Leibniz Institute for Catalysis e.V. Albert-Einstein-Strasse 29aRostock18059Germany School of Materials Science and Engineering Ocean University of ChinaQingdao266100P.R.China Shenzhen Key Laboratory of Micro/Nano-Porous Functional Materials(SKLPM) SUSTech-Kyoto University Advanced Energy Materials Joint Innovation Laboratory(SKAEM-JIL)Key University Laboratory of Highly Efficient Utilization of Solar Energy and Sustainable Development of GuangdongDepartment of Chemistry and Department of Materials Science and EngineeringSouthern University of Science and Technology(SUSTech)Shenzhen518055P.R.China

PtCo nanoalloys(NAs)deposited on carbon black are emerging as robust electrocatalysts for addressing the sluggish kinetic issue of oxygen reduction reaction(ORR).However,developing a simple and low-cost method to synthesize PtCo/C with excellent performance is still a great *** this work,a one-pot method was used to successfully obtain the PtCo NAs on commercial carbon supports of acetylene black and Ketjenblack ECP600JD,*** with those grown on Ketjenblack ECP600JD,the PtCo NAs grown on acetylene black exhibited higher electrochemical surface area(ECSA)and mass activity(MA),which may be attributed to the different particle sizes of PtCo NAs,distinct hydrophilicity,electroconductivity and charge distribution between the carbon supports and PtCo *** study provides valuable insights into the optimal design of carbon-supported ORR electrocatalysts with exceptional activity and durability.

关键词： Oxygen reduction reaction PtCo nanoalloy Carbon-supported nanostructure Acetylene black

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How the enhanced East Asian summer monsoon regulates total gross primary production in eastern China

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Advances in Climate Change Research 2024年第2期15卷 244-252页

作者： Ming-yu HAN Yong ZHANG Jing peng China State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081China China Meteorological Administration Institute for Development and Programme Design Beijing 100081China CAS Key Laboratory of Regional Climate-Environment for Temperate East Asia Institute of Atmospheric PhysicsChinese Academy of Sciences(CAS)Beijing 100029China

Recognizing the relationship between gross primary production(GPP)and precipitation in eastern China,the East Asian Summer Monsoon(EASM)plays a crucial role in shaping *** confirmation of the strong link between EASM and GPP,there remains a notable research gap in understanding the specific impact of the EASM on GPP in different regions of eastern *** we used simulations from Trends in Net Land-Atmosphere Carbon Exchanges(TRENDY)models from 1951 to 2010 and divided eastern China into five subregions for the *** also used the New East Asian Summer Monsoon Index(NEWI)as a quantitative metric to distinguish between periods of strong and weak *** on this,this study aims to investigate the response of GPP in different subregions of eastern ***,under strengthened EASM years(1954,1957,1965,1969,1977,1980,1983,1987,1993 and 1998),East China experienced the most pronounced increase in GPP at 12±21(mean±1 sigma)gC m^(-2) mon^(-1) compared to the weak EASM years(1958,1961,1972,1973,1978,1981,1985,1994,1997 and 2004).In contrast,Southwest China showed a decline in GPP at-4±10 gC m^(-2) mon^(-1).Moreover,GPP also increased in Northeast and North China when EASM strengthened,while South China showed a decline in *** indicated that GPP changed with monsoon *** to the mechanism analysis,during strong EASM,there was intense moisture convergence through alterations in the atmospheric circulation field over East China and abundant precipitation,which further contributed to the increase in *** solar radiation in Southwest China decreased with EASM enhancement,which suppressed GPP and hindered vegetation ***,the results highlight the importance of accurately predicting the impact of different EASM intensities of regional carbon fluxes.

关键词： Gross primary production Surface air temperature Precipitation Solar radiation Eastern China Carbon cycle

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Rhizosphere microbes influence wogonoside accumulation in perennial Scutellaria baicalensis

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Pedosphere 2024年第3期34卷 553-566页

作者： Yang SUN Hong liU Junwei peng Minchong SHEN Yang HU Dongsheng yu Jiangang li yuanhua DONG CAS Key Laboratory of Soil Environment and Pollution Remediation Institute of Soil ScienceChinese Academy of SciencesNanjing 210008(China) University of Chinese Academy of Sciences Beijing 100049(China) Tobacco Research Institute of Chinese Academy of Agricultural Sciences Qingdao 266101(China)

Dried roots of Scutellaria baicalensis Georgi are an acclaimed traditional Chinese medicine,and wogonoside content is a key indicator used to evaluate *** *** than rising linearly with cultivation years,*** quality initially increases and then ***,little is known regarding the dynamic variations in *** rhizosphere microorganisms under long-term cultivation and underlying mechanisms of their effects on wogonoside formation and *** aim of this study was to investigate the roles of soil nutrients and rhizosphere microbes on *** quality across different cultivation years(1-4 years).The wogonoside content(25.14 mg g^(-1))was highest in the biennial *** and then decreased following long-term *** soil nutrients(available nitrogen,available phosphorus,available iron,available manganese,and available zinc)were reduced significantly as cultivation years *** also affected rhizosphere bacterial community structure significantly,driving it toward deterministic process(i.e.,β-nearest taxon indexlity under long-term cultivation from the perspective of soil nutrients and microorganisms,which may theoretically support the future artificial cultivation and management of Chinese medicinal plants.

关键词： bacterial diversity medicinal plant rhizosphere bacterial community soil nutrient wogonoside content wogonoside formation

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Enhanced cyclic stability of partially disordered spinel cathodes through direct fluorination with gaseous fluorine

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Rare Metals 2024年第4期43卷 1635-1646页

作者： Yong-Nian Ma ling-Chen Kong Shao-Shan Chen Yong Wang li-Dong Sun Cong peng Meng-Meng Qin yu li Wei Feng Tianjin Key Laboratory of Composite and Functional Materials School of Materials Science and EngineeringTianjin UniversityTianjin300072China Institute of Advanced Technology and Equipment Beijing University of Chemical TechnologyBeijing100029China

Spinel-type cathodes are considered an optimal substitute for conventional layered oxide cathodes owing to their use of inexpensive and earth-abundant manganese as the redox-active ***,the introduction of cation disorder can effectively suppress the detrimental two-phase reaction to realize high capacities in a wide voltage ***,the continuous capacity decay during cycles has hindered the widespread application of these cathode *** fluorides exhibit excellent electrochemical stability at high voltage;therefore,in this study,the direct F2 gas reaction with a partially disordered spinel cathode(li_(1.6)Mn_(1.6)O_(3.7)F_(0.3,)LMOF1.6)was initially applied to investigate the impacts of fluorination on the surface structure and electrochemical *** inorganic fluorinated layer,mainly containing liF,was distributed uniformly on the surface of LMOF1.6nanoparticles after fluorination for an appropriate time without the turbulence caused by the valency of manganese cation,which improved the capacity retention and rate capability by the suppression of structural damage,parasitic reaction,and cation *** LMOF1.6cathode fluorinated for 0.5 h exhibited a capacity of283.6 mAh·g^(-1)at 50 mA·g^(-1)and an enhanced capacity retention of 29.6%after 50 cycles in the voltage range of1.5-4.8 V,as compared to the pristine LMOF1.6 with only27.9%capacity retention.

关键词： Spinel-type cathodes Direct fluorination Capacity retention ability High rate capability

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Divergent contributions of spring and autumn photosynthetic phenology to seasonal carbon uptake of subtropical vegetation in China

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Journal of Geographical Sciences 2024年第7期34卷 1280-1296页

作者： peng Ying li peng ZHOU Xiaolu LUO yunpeng ZHANG Cicheng WANG Longjun li Tong peng Changhui School of Geographic Sciences Hunan Normal UniversityChangsha410081China Department for Biogeochemical Integration Max-Planck-Institute for BiogeochemistryJena07745Germany Department of Biology Sciences Institute of Environment SciencesUniversity of Quebec at MontrealC.P.8888Succ.Centre-VilleMontrealH3C 3P8Canada

Phenological changes play a central role in regulating seasonal variation in the ecological processes,exerting significant impacts on hydrologic and nutrient cycles,and ultimately influencing ecosystem functioning such as carbon ***,the potential impact mechanisms of phenological events on seasonal carbon dynamics in subtropical regions are *** knowledge gaps hinder from accurately linking photosynthetic phenology and carbon sequestration *** chlorophyll fluorescence remote sensing and productivity data from 2000 to 2019,we found that an advancement in spring phenology increased spring gross(GPP)and net primary productivity(NPP)in subtropical vegetation of China by 2.1 gC m^(-2)yr^(-1)and 1.4 gC m^(-2)yr^(-1),respectively.A delay in autumn phenology increased the autumnal GPP and NPP by 0.4 gC m^(-2)yr^(-1)and 0.2 gC m^(-2)yr^(-1),***,the contribution of the spring phenology to spring carbon uptake increased significantly during the study period,while this positive contribution showed a nonsignificant trend in *** comparison,the later autumn phenology could significantly contribute to the increase in autumnal carbon uptake;however,this contributing effect was *** analysis indicated that these phenomena have been caused by the increased leaf area and enhanced photosynthesis due to earlier spring and later autumn phenology,*** results demonstrate the diverse impacts of vegetation phenology on the seasonal carbon sequestration ability and it is imperative to consider such asymmetric effects when modeling ecosystem processes parameterized under future climate change.

关键词： subtropics vegetation phenology remote sensing carbon cycle climate change

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Acute suppurative terminal cholangitis:Clinical characteristics of a new subtype of acute cholangitis

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Hepatobiliary & Pancreatic Diseases International 2024年第3期23卷 293-299页

作者： Rong-Tao Zhu Ye li Chi-Xian Zhang Wei-Jie Wang Ruo-peng liang Jian li Kai Bai yu-ling Sun Department of Hepatobiliary and Pancreatic Surgery the First Affiliated Hospital of Zhengzhou UniversityZhengzhou 450052China Zhengzhou Key Laboratory of Hepatobiliary and Pancreatic Diseases Zhengzhou 450052China Institute of Hepatobiliary and Pancreatic Diseases Zhengzhou UniversityZhengzhou 450052China Department of Pathology the First Affiliated Hospital of Zhengzhou UniversityZhengzhou 450052China

Background:Acute suppurative terminal cholangitis(ASTC)is rarer than acute obstructive cholangitis and is not well *** explore this subtype of acute cholangitis,we described our clinical experience with ***:We performed a retrospective review of patients with ASTC admitted to our center from September 2014 to August *** analyzed their clinical characteristics,including etiology,clinical manifestations,imaging features,treatment and ***:A total of 32 ASTC patients were included in the *** majority of the patients had a history of biliary operations,and clinical manifestations were occult and *** positive rate of bacterial culture was 46.9%.All the patients had typical imaging features on computed tomography and magnetic resonance *** with effective antibiotics was provided as soon as diagnosis was *** treatment,most patients had a good *** levels of total bilirubin,aspartate aminotransferase,procalcitonin and gamma-glutamyltransferase were the characteristics of critically ill patients and were associated with relatively poor ***:Our results demonstrated that ASTC should be recognized as a new subtype of acute cholangitis,and that earlier diagnosis and more personalized treatments are needed.

关键词： Acute suppurative terminal cholangitis Acute cholangitis Gram-negative bacterial infections Diagnosis Treatment

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April-September minimum temperature reconstruction based on Sabina tibetica ring-width chronology in the central eastern Tibetan Plateau,China

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Journal of Forestry Research 2024年第2期35卷 134-145页

作者： Teng li Jianfeng peng Tsun Fung Au Jinbao li School of Geography and Remote Sensing Guangzhou UniversityGuangzhou 510006People’s Republic of China College of Geography and Environmental Science Henan UniversityKaifeng 475004People’s Republic of China Institute for Global Change Biology School for Environment and SustainabilityUniversity of MichiganAnn ArborMIUSA Department of Ecology and Evolutionary Biology University of MichiganAnn ArborMIUSA Department of Geography University of Hong KongHong Kong SARPeople’s Republic of China HKU Shenzhen Institute of Research and Innovation Shenzhen 518057People’s Republic of China

Minimum temperatures have remarkable impacts on tree growth at high-elevation sites on the Tibetan Plateau,but the shortage of long-term and high-resolution paleoclimate records inhibits understanding of recent minimum temperature *** this study,a warm season(April–September)reconstruction is presented for the past 467 years(1550–2016)based on Sabina tibetica ring-width chronology on the lianbaoyeze Mountain of the central eastern Tibetan *** warm periods and eight cold periods were ***-term minimum temperature variations revealed a high degree of coherence with nearby *** correlations between our reconstruction and global sea surface temperatures suggest that warm season minimum temperature anomalies in the central eastern Tibetan Plateau were strongly influenced by large-scale ocean atmospheric circulations,such as the El Ni?o-Southern Oscillation and the Atlantic Multidecadal Oscillation.

关键词： Tree-ring analysis Sabina tibetica Minimum temperatures Central eastern Tibetan Plateau Climate change

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