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Journal of Rare Earths 2024年第2期42卷 256-262,I0001页

作者： Tianqi Cao Yuxin Liu Qi Jia xiaolu Wang Shouqiang Zhang Jing zhou Department of Chemistry Capital Normal UniversityBeijing100048China

Chemotherapy,the use of antitumor drugs to kill cancer cells,is currently one of the most effective treatments for cancer.However,serious toxic side effects caused by long-term drug accumulation can cause significant damage to the body,which limits the clinical application of antitumor drugs.In this study,a novel RENPs@DOX-Fe nanoprobe(NP) was constructed by coating the surface of rare earth nanomaterials(NaLuF_(4):Yb,Er) with a complex formed by doxorubicin(DOX) and iron ion(Ⅲ).Due to the low toxicity of anthracycline-metal complexes,the damage to normal cells is reduced.The unique acidic microenvironment in tumor cells facilitates the decomposition and gradual release of DOX from the DOX-Fe complex.In addition,the DOX-Fe complex can convert near-infrared(NIR) light into heat energy,which promotes the decomposition of the complex,further enhancing the release of DOX in the tumor environment.The change of ratio fluorescence of rare earth nanomaterials at 660 and 1550 nm after DOX release enables visual monitoring of drug release,which can potentially improve the chemotherapeutic effect.In vitro experiments established that RENPs@DOX-Fe NPs with NIR illumination had good therapeutic efficacy in tumors.This work provides new insights into designing tumor microenvironment-responsive nanoprobes for chemotherapy with minimal side effects.

关键词： Rare earth nanoprobes Fluorescence Ratiometric imaging DOX Chemotherapy

COF-based membranes for liquid phase separation:Preparation,mechanism and perspective

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Journal of Environmental Sciences 2024年第7期141卷 63-89页

作者： Yujie Zhao He Gu Yilun zhou CaimeiWen xiaolu Liu Suhua Wang Zhongshan Chen Hui Yang Xiangke Wang College of Environmental Science and Engineering North China Electric Power UniversityBeijing 102206China School of Environmental Science and Engineering Guangdong University of Petrochemical TechnologyMaoming 525000China

Covalent organic frameworks(COFs)are a new kind of crystalline porous materials composed of organic molecules connected by covalent bonds,processes the characteristics of low density,large specific surface area,adjustable pore size and structure,and easy to functionalize,which have been widely used in the field of membrane separation technology.Recently,there are more and more researches focusing on the preparation methods,separation application,and mechanism of COF membranes,which need to be further summarized and compared.In this review,we primarily summarized several conventional preparation methods,such as two-phase interfacial polymerization,in-situ growth on substrate,unidirectional diffusion method,layer-by-layer assembly method,mixed matrix membranes,and so on.The advantages and disadvantages of each method are briefly summarized.The application potential of COF membrane in liquid separation are introduced from four aspects:dyeing wastewater treatment,heavy metal removal,seawater desalination and oil-water separation.Then,the mechanisms including pore structure,hydrophilic/hydrophobic,electrostatic repulsion/attraction and Donnan effect are introduced.For the efficient removal of different kind of pollutions,researchers can select different ligands to construct membranes with specific pore size,hydrophily,salt or organic rejection ability and functional group.The ideas for the design and preparation of COF membranes are introduced.Finally,the future direction and challenges of the next generation of COF membranes in the field of separation are prospected.

关键词： Covalent organic frameworks Membrane materials Liquid phase separation Separation mechanism

Divergent response of vegetation phenology to extreme temperatures and precipitation of different intensities on the Tibetan Plateau

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Science China Earth Sciences 2023年第10期66卷 2200-2210页

作者： Mai SUN Peng LI Peixin REN Jiayi TANG Cicheng ZHANG xiaolu zhou Changhui PENG School of Geographic Sciences Hunan Normal UniversityChangsha410081China Department of Biology Sciences Institute of Environment SciencesUniversity of Quebec at MontrealMontrealH3C 3P8Canada

Quantifying how climate factors affect vegetation phenology is crucial for understanding climate-vegetation interactions and carbon and water cycles under a changing climate.However,the effects of different intensities of extreme climatic events on vegetation phenology remain poorly understood.Using a long-term solar-induced chlorophyll fluorescence dataset,we investigated the response of vegetation phenology to extreme temperatures and precipitation events of different intensities across the Tibetan Plateau(TP)from 2000 to 2018.We found that the effect of maximum temperature exposure days(TxED)and minimum temperature exposure days(TnED)on the start of the growing season(SOS)was initially delayed and shifted to advance along the increasing temperature gradients.However,the response of the end of the growing season(EOS)to TxED and TnED shifted from an advance to a delay with increasing temperature gradients until the temperature thresholds were reached,above which thresholds produced an unfavorable response to vegetation growth and brought the EOS to an early end.The corresponding maximum and minimum temperature thresholds were 10.12 and 2.54℃,respectively.In contrast,cumulative precipitation(CP)was more likely to advance SOS and delay EOS as the precipitation gradient increased,but the advance of SOS is gradually weakening.Four vegetation types(i.e.,forest,shrubland,meadow,and steppe)showed similar trends in response to different climates,but the optimal climatic conditions varied between the vegetation types.Generally,meadow and steppe had lower optimal temperatures and precipitation than forest and shrubland.These findings revealed the divergent responses of vegetation phenology to extreme climate events of different intensities,implying that the SOS will continue to advance with warming,whereas the EOS may undergo a partial transformation from delayed areas to advanced areas with continued warming.

关键词： Vegetation phenology Extreme climates Optimal climate Solar-induced chlorophyll fluorescence Tibetan Plateau

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 1280-1302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 University Department for Biogeochemical Integration Max-Planck-Institute for Biogeochemistry Department of Biology Sciences Institute of Environment Sciences University of Quebec at Montreal

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 uptake.However,the potential impact mechanisms of phenological events on seasonal carbon dynamics in subtropical regions are under-investigated.These knowledge gaps hinder from accurately linking photosynthetic phenology and carbon sequestration capacity.Using 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-2yr-1and 1.4 gC m-2yr-1,respectively.A delay in autumn phenology increased the autumnal GPP and NPP by 0.4 gC m-2yr-1and 0.2 gC m-2yr-1,respectively.Temporally,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 summer.In comparison,the later autumn phenology could significantly contribute to the increase in autumnal carbon uptake;however,this contributing effect was weakened.Path analysis indicated that these phenomena have been caused by the increased leaf area and enhanced photosynthesis due to earlier spring and later autumn phenology,respectively.Our 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

Spatiotemporal analysis of the impact of urban landscape forms on PM_(2.5) in China from 2001 to 2020

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International Journal of Digital Earth 2023年第1期16卷 3417-3434页

作者： Shoutao Zhu Jiayi Tang xiaolu zhou Peng Li Zelin Liu Cicheng Zhang Ziying Zou Tong Li Changhui Peng School of Geographic Sciences Hunan Normal UniversityChangshaPeople’s Republic of China Department of Biology Sciences Institute of Environment SciencesUniversity of Quebec at MontrealMontrealCanada

Urban landscape forms can be effective in reducing increasing PM_(2.5) concentrations due to urbanization in China,making it crucially important to accurately quantify the spatiotemporal impact of urban landscape forms on PM_(2.5) variations.Three landscape indices and six control variables were selected to assess these impacts in 362 Chinese cities during different time scales from 2001 to 2020,using a spatiotemporal geographically weighted regression model,random forest models and partial dependence plots.The results show that there are spatiotemporal differences in the impacts of landscape indices on PM_(2.5).the proportion of urban green infrastructure(PLAND-UGI)and the fractal dimension of urban green infrastructure(FRACT-UGI)exacerbate PM_(2.5) concentrations in the northwest,the proportion of impervious surfaces(PLAND-Impervious)mitigates air pollution in northwest and southwest China,and shannon’s diversity index(SHDI)has seasonal differences in the northwest.PLAND-UGI is the landscape index with the largest contribution(30%)and interpretable range.The relationship between FRACT and PM_(2.5) was more complex than for other landscape indices.The results of this study contribute to a deeper understanding of the spatial and temporal differences in the impact of urban landscape patterns on PM_(2.5),contributing to clean urban development and sustainable development.

关键词： Landscape index particulate matter spatiotemporal heterogeneity spatiotemporal geographically weighted regression model random forest

Re-estimating the changes and ranges of forest biomass carbon in China during the past 40 years

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Forest Ecosystems 2019年第4期6卷 396-413页

作者： xiaolu zhou Xiangdong Lei Caixia Liu Huabing Huang Carl zhou Changhui Peng Research Center for Ecological Forecasting and Global Change Northwest A&F UniversityYangling 712100China Ecological Modeling and Carbon Science Department of Biology ScienceUniversity of Quebec at MontrealMontrealQC H3C 3P8Canada Institute of Forest Resource Information Techniques Chinese Academy of ForestryBeijing 100091China State Key Laboratory of Remote Sensing Science Institute of Remote Sensing and Digital EarthChinese Academy of SciencesBeijing 100101China Faculty of Health Sciences University of OttawaOttawaON K1N 6N5Canada.

Background: In recent decades the future of global forests has been a matter of increasing concern, particularly in relation to the threat of forest ecosystem responses under potential climate change. To the future predictions of these responses, the current forest biomass carbon storage(FCS) should first be clarified as much as possible,especially at national scales. However, few studies have introduced how to verify an FCS estimate by delimiting the reasonable ranges. This paper addresses an estimation of national FCS and its verification using two-step process to narrow the uncertainty. Our study focuses on a methodology for reducing the uncertainty resulted by converting from growing stock volume to above-and below-ground biomass(AB biomass), so as to eliminate the significant bias in national scale estimations.Methods: We recommend splitting the estimation into two parts, one part for stem and the other part for AB biomass to preclude possible significant bias. Our method estimates the stem biomass from volume and wood density(WD), and converts the AB biomass from stem biomass by using allometric relationships.Results: Based on the presented two-step process, the estimation of China’s FCS is performed as an example to explicate how to infer the ranges of national FCS. The experimental results demonstrate a national FCS estimation within the reasonable ranges(relative errors: + 4.46% and-4.44%), e.g., 5.6–6.1 PgC for China’s forest ecosystem at the beginning of the 2010 s. These ranges are less than 0.52 PgC for confirming each FCS estimate of different periods during the last 40 years. In addition, our results suggest the upper-limits by specifying a highly impractical value of WD(0.7 t·m-3) on the national scale. As a control reference, this value decides what estimate is impossible to achieve for the FCS estimates.Conclusions: Presented methodological analysis highlights the possibility to determine a range that the true value could be located in. The two-step process will help to verify national FCS and a

关键词： Allometric equation Forest carbon Stem-biomass proportion Volume-derived method Wood density

Strong controls of daily minimum temperature on the autumn photosynthetic phenology of subtropical vegetation in China

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Forest Ecosystems 2021年第3期8卷 413-424页

作者： Peixin Ren Zelin Liu xiaolu zhou Changhui Peng Jingfeng Xiao Songhan Wang Xing Li Peng Li College of Geographic Science Hunan Normal UniversityChangsha 410081China Department of Biology Sciences Institute of Environment SciencesUniversity of Quebec at MontrealC.P.8888Succ.Centre-VilleMontreal H3C 3P8Canada Earth Systems Research Center Institute for the Study of EarthOceansand SpaceUniversity of New HampshireDurhamNH 03824USA International Institute for Earth System Sciences Nanjing UniversityNanjing 210023China Jiangsu Provincial Key Laboratory of Geographic Information Technology Key Laboratory for Land Satellite Remote Sensing Applications of Ministry of Natural ResourcesSchool of Geography and Ocean ScienceNanjing UniversityNanjing 210023China

Background:Vegetation phenology research has largely focused on temperate deciduous forests,thus limiting our understanding of the response of evergreen vegetation to climate change in tropical and subtropical regions.Results:Using satellite solar-induced chlorophyll fluorescence(SIF)and MODIS enhanced vegetation index(EVI)data,we applied two methods to evaluate temporal and spatial patterns of the end of the growing season(EGS)in subtropical vegetation in China,and analyze the dependence of EGS on preseason maximum and minimum temperatures as well as cumulative precipitation.Our results indicated that the averaged EGS derived from the SIF and EVI based on the two methods(dynamic threshold method and derivative method)was later than that derived from gross primary productivity(GPP)based on the eddy covariance technique,and the time-lag for EGSsif and EGSevi was approximately 2 weeks and 4 weeks,respectively.We found that EGS was positively correlated with preseason minimum temperature and cumulative precipitation(accounting for more than 73%and 62%of the study areas,respectively),but negatively correlated with preseason maximum temperature(accounting for more than 59%of the study areas).In addition,EGS was more sensitive to the changes in the preseason minimum temperature than to other climatic factors,and an increase in the preseason minimum temperature significantly delayed the EGS in evergreen forests,shrub and grassland.Conclusions:Our results indicated that the SIF outperformed traditional vegetation indices in capturing the autumn photosynthetic phenology of evergreen forest in the subtropical region of China.We found that minimum temperature plays a significant role in determining autumn photosynthetic phenology in the study region.These findings contribute to improving our understanding of the response of the EGS to climate change in subtropical vegetation of China,and provide a new perspective for accurately evaluating the role played by evergreen vegetation in the regional carbon budget.

关键词： Carbon cycle Evergreen vegetation Plant phenology Solar-induced Fluorescence Climate change MODIS Eddy covariance

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新疆椒麻鸡腿的品质变化及货架期预测

食品工业科技 2024年第7期45卷 306-312页

作者：周晓璐李雅雯许倩任晓镤牛希跃塔里木大学食品科学与工程学院新疆阿拉尔843300 南疆特色农产品深加工兵团重点实验室新疆阿拉尔843300 塔里木大学分析测试中心新疆阿拉尔843300

为了探究新疆椒麻鸡腿贮藏期间品质变化并对其货架期进行预测。本文以新疆椒麻鸡腿为研究对象,以酸碱度值(Potential of hydrogen,pH)、色泽、硫代巴比妥酸值(Thiobarbituric acid reactive substances,TBARS)、挥发性盐基氮(Total vola... 详细信息

为了探究新疆椒麻鸡腿贮藏期间品质变化并对其货架期进行预测。本文以新疆椒麻鸡腿为研究对象,以酸碱度值(Potential of hydrogen,pH)、色泽、硫代巴比妥酸值(Thiobarbituric acid reactive substances,TBARS)、挥发性盐基氮(Total volatile basic nitrogen,TVB-N)、菌落总数、大肠菌群及感官品质为评价指标,利用加速性破坏实验,研究不同贮藏温度(35℃和45℃)下椒麻鸡腿的品质变化,以感官得分70分或菌落总数接近国家标准作为货架期终点,并预测出常温(25℃)下椒麻鸡腿的货架期。结果表明:不同贮藏温度下的椒麻鸡腿随着贮藏时间的不断延长,pH呈先下降后上升趋势,L^(*)值整体呈下降趋势,而a^(*)值、b^(*)值、TBARS值、TVB-N含量和菌落总数均呈上升趋势,感官评分则不断下降,在贮藏期且45℃的变化速率高于35℃,在35℃贮藏温度下,理论货架期为24 d,在45℃贮藏温度下,理论货架期为9 d,在货架期终点样品品质出现不可接受的损失。根据Q_(10)模型计算出Q_(10)=2.6,根据模型预测出常温(25℃)条件下理论货架期为62 d。

关键词：新疆椒麻鸡腿品质变化贮藏温度货架期加速实验

The development of an iridium(Ⅲ) complex functionalized G-quadruplex probe for the stability of G-quadruplex and lifetime image in cytoplasm

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中国化学快报：英文版 2023年第2期34卷 397-402页

作者： Shaokang Jia Wenjin Wang Shanshan Qin Shengjie Xie Lisi Zhan Qi Wei Ziang Lu xiaolu zhou Cong Chen Kun Chen Shen Yan Caiping Tan Zongwan Mao Xiang zhou College of Chemistry and Molecular Sciences Key Laboratory of Biomedical Polymers-Ministry of EducationWuhan UniversityWuhan 430072China MOE Key Laboratory of Bioinorganic and Synthetic Chemistry School of ChemistrySun Yat-sen UniversityGuangzhou 510275China

G-quadruplex(G4) is widely known as a non-classical secondary structure of nucleic acid. With the indepth study of G4, it is an urgent need for a phosphorescent probe with a high G4 binding ability to evaluate the level of G4 in the cytoplasm. Thus, this study designed and synthesized Ir-PDP where an Ir(Ⅲ)complex was used as a phosphorescent emitter. Meanwhile, two installed PDPs(pyridostatin derivatives)were used to improve the combination ability with G4 and reduced the cytotoxicity of the Ir(Ⅲ) complex.Compared with other nucleic acid secondary structures, Ir-PDP produced a higher phosphorescence lifetime after interacting with G4. Ir-PDP was distributed in the cytoplasm of living cells, and two-photon phosphorescence lifetime imaging can detect the binding events of the probe in the cytoplasm. The addition of G4 binder PDS significantly regulated cytoplasmic phosphorescence lifetime. The project explored a new sensing pathway to observe the binding manners of probes in the cytoplasm through the phosphorescence lifetime of probes.

关键词： G-quadruplex Pyridostatin derivatives Iridium(Ⅲ)complex Phosphorescent probe Phosphorescence lifetime Cell imaging

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考虑区域间辅助奖励的配电网电压优化控制

电力建设 2024年第5期45卷 80-93页

作者：周祥李晓露柳劲松林顺富上海电力大学电气工程学院上海市200090 国网上海市电力公司电力科学研究院上海市200437

智能软开关能够有效解决分布式光伏大规模接入配电网引起的电压波动问题,但会导致区域间协作程度加深,而现阶段使用多智能体深度强化学习算法进行电压优化时,各智能体仅使用各自区域内的奖励进行训练,导致智能体缺乏协同,输出策略难以... 详细信息

智能软开关能够有效解决分布式光伏大规模接入配电网引起的电压波动问题,但会导致区域间协作程度加深,而现阶段使用多智能体深度强化学习算法进行电压优化时,各智能体仅使用各自区域内的奖励进行训练,导致智能体缺乏协同,输出策略难以保证最优性。为此提出考虑区域间辅助奖励的配电网电压优化方法,首先建立基于多智能体深度强化学习的多时间尺度电压优化框架,其次针对控制智能软开关的智能体,将各自区域内奖励定义为主奖励,邻近区域内奖励定义为辅助奖励,然后通过主、辅助奖励损失函数关于网络参数梯度的数量积分析辅助奖励对训练的有利程度,并采用演化博弈方法自适应修改辅助奖励参与因子;最后,在改进的IEEE 33节点系统验证了所提方法能够稳定智能体训练过程,提升智能体策略的优化效果。

关键词：多智能体深度强化学习电压优化辅助奖励演化博弈参与因子