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The connection of phytoplankton biomass in the Marguerite Bay polynya of the western Antarctic Peninsula to the Southern Annular Mode

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Acta Oceanologica Sinica 2024年第1期43卷 35-47页

作者： Ning Jiang Zhaoru zhang ruifeng zhang Chuning Wang Meng Zhou School of Oceanography Shanghai Jiao Tong UniversityShanghai 200240China Key Laboratory for Polar Science Polar Research Institute of ChinaMinistry of Natural ResourcesShanghai 200136China

Antarctic coastal polynyas are biological hotspots in the Southern Ocean that support the abundance of hightrophic-level predators and are important for carbon cycling in the high-latitude oceans.In this study,we examined the interannual variation of summertime phytoplankton biomass in the Marguerite Bay polynya(MBP)in the western Antarctic Peninsula area,and linked such variability to the Southern Annular Mode(SAM)that dominated the southern hemisphere extratropical climate variability.Combining satellite data,atmosphere reanalysis products and numerical simulations,we found that the interannual variation of summer chlorophyll-a(Chl-a)concentration in the MBP is significantly and negatively correlated with the spring SAM index,and weakly correlated with the summer SAM index.The negative relation between summer Chl-a and spring SAM is due to weaker spring vertical mixing under a more positive SAM condition,which would inhibit the supply of iron from deep layers into the surface euphotic layer.The negative relation between spring mixing and spring SAM results from greater precipitation rate over the MBP region in positive SAM phase,which leads to lower salinity in the ocean surface layer.The coupled physical-biological mechanisms between SAM and phytoplankton biomass revealed in this study is important for us to predict the future variations of phytoplankton biomasses in Antarctic polynyas under climate change.

关键词： Marguerite Bay polynya phytoplankton biomass Southern Annular Mode mixed layer depth interannual variation

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Typhoon-and pollution-driven enhancement of reactive bromine in the mid-latitude marine boundary layer

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National Science Review 2024年第4期11卷 93-101页

作者： Shanshan Wang Qinyi Li ruifeng zhang Anoop Sharad Mahajan Swaleha Inamdar Nuria Benavent Sanbao zhang Ruibin Xue Jian Zhu Chenji Jin Yan zhang Xiao Fu Alba Badia Rafael P.Fernandez Carlos A.Cuevas Tao Wang Bin Zhou Alfonso Saiz-Lopez Institute for Interdisciplinary Science (ICB) National Research Council (CONICET) Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention (LAP3) Department of Environmental Science and Engineering Fudan University Institute of Eco-Chongming(IEC) Department of Atmospheric Chemistry and Climate Institute of Physical Chemistry Blas CabreraCSIC Department of Civil and Environmental Engineering The Hong Kong Polytechnic University Environment Research Institute Shandong University Centre for Climate Change Research Indian Institute of Tropical MeteorologyMinistry of Earth Sciences Department of Chemistry University of Colorado Boulder Institute of Environment and Ecology Tsinghua Shenzhen International Graduate SchoolTsinghua University Sostenipra Research Group Institute of Environmental Science and Technology(ICTA)Universitat Autonoma de Barcelona(UAB)

Tropospheric reactive bromine is important for atmospheric chemistry,regional air pollution,and global climate.Previous studies have reported measurements of atmospheric reactive bromine species in different environments,and proposed their main sources,e.***.sea-salt aerosol（SSA）,oceanic biogenic activity,polar snow/ice,and volcanoes.Typhoons and other strong cyclonic activities（e.***.hurricanes） induce abrupt changes in different earth system processes,causing widespread destructive effects.However,the role of typhoons in regulating reactive bromine abundance and sources remains unexplored.Here,we report field observations of bromine oxide（BrO）,a critical indicator of reactive bromine,on the Huaniao Island（HNI）in the East China Sea in July 2018.We observed high levels of BrO below 500 m with a daytime average of9.7±4.2 pptv and a peak value of ～26 pptv under the influence of a typhoon.Our field measurements,supported by model simulations,suggest that the typhoon-induced drastic increase in wind speed amplifies the emission of SSA,significantly enhancing the activation of reactive bromine from SSA debromination.We also detected enhanced BrO mixing ratios under high NOxconditions（ppbv level） suggesting a potential pollution-induced mechanism of bromine release from SSA.Such elevated levels of atmospheric bromine noticeably increase ozone destruction by as much as ～40% across the East China Sea.Considering the high frequency of cyclonic activity in the northern hemisphere,reactive bromine chemistry is expected to play a more important role than previously thought in affecting coastal air quality and atmospheric oxidation capacity.We suggest that models need to consider the hitherto overlooked typhoon-and pollution-mediated increase in reactive bromine levels when assessing the synergic effects of cyclonic activities on the earth system.

关键词： reactive bromine atmospheric chemistry marine boundary layer atmospheric oxidation capacity marine emission

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Measurable n-sensitivity and maximal pattern entropy

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Frontiers of Mathematics in China 2022年第6期17卷 1169-1180页

作者： ruifeng zhang School of Mathematics Hefei University TechnologyHefei230009China

We introduce the notion of measurable n-sensitivity for measure preserving systems,and study the relation between measurable n-sensitivity and the maximal pattern entropy.We prove that,if(X,ℬ,μ,T)is ergodic,then(X,ℬ,μ,T)is measurable n-sensitive but not measurable(n+1)-sensitive if and only if h_(μ)^(*)(T)=log n,where h_(μ)^(*)(T)is the maximal pattern entropy of T.

关键词： Measurable n-sensitive sequence entropy maximal pattern entropy

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Tungsten separation behavior on preparation of high-purity cerium by combined vacuum gravity sedimentation-directional solidification

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Journal of Rare Earths 2024年第6期42卷 1182-1186,I0007页

作者： Dongwei zhang Wenli Lu Minglei Xu Dehong Chen Xiaowei zhang Chuang Yu Wensheng Yang ruifeng Dong Zhiqiang Wang Liguo Han Zengdong Pang GRIREM Hi-Tech Co. Ltd.Langfang065201China National Engineering Research Center for Rare Earth China GRINM Group Co.Ltd.Beijing100088China GRIREM Advanced Materials Co. Ltd.Beijing100088China

In light of the difficult removal of harmful impurity tungsten(W)in Ce metal,in this paper a combined vacuum gravity sedimentation-directional solidification method was innovatively designed and the W separation behavior was investigated.By reducing the electron beam power instantly and gradually at reduction rates of 1,3 and 5 kW/min,it is found that W is enriched at the bottom of ingots as the melt solidifies.The enrichment effect is much better than that of single purification method and the enrichment degree increases as the beam reduction rate decreases,attributed to the k0(W)>1 andρ(W)>ρ(Ce).Overall,the minimum content of W impurity can decrease from 630 to 0.1 ppm at the top of the ingot,and the purity of Ce increases from 99.932 wt%to 99.995 wt%by this combined method.Additionally,this paper provides a new method for the removal of high density and low evaporation coefficient impurities in low vapor pressure rare earth metals.

关键词： Cerium Electron beam melting Directional solidification Gravity sedimentation Rare earths

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MAX-DOAS observation in the midlatitude marine boundary layer: Influences of typhoon forced air mass

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Journal of Environmental Sciences 2022年第10期34卷 63-73页

作者： ruifeng zhang Shanshan Wang Sanbao zhang Ruibin Xue Jian Zhu Bin Zhou Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention(LAP3) Department of Environmental Science and EngineeringFudan UniversityShanghai 200438China Institute of Eco-Chongming(IEC) No.20 Cuiniao RoadShanghai 202162China Zhuhai Fudan Innovation Institute Zhuhai 519000China Institute of Atmospheric Sciences Fudan UniversityShanghai 200433China

As a passive remote sensing technique,MAX-DOAS method was widely used to investigate the vertical profiles of aerosol and trace gases in the lower troposphere.However,the measurements for midlatitude marine boundary layer are rarely reported,especially during the storm weather system.In this study,the MAX-DOAS was used to retrieve the aerosol,HCHO and NO_(2) vertical distribution at Huaniao Island of East China Sea in summer 2018,during which a strong tropical cyclone developed and passed through the measurement site.The observed aerosol optical depth(AOD),HCHO-and NO_(2)-VCDs(Vertical Column Density)were in the range of 0.19-0.97,(2.57-12.27)×10^(15) molec/cm^(2),(1.24-4.71)×10^(15) molec/cm^(2),which is much higher than remote ocean area due to the short distance to continent.The vertically resolved aerosol extinction coefficient(AEC),HCHO and NO_(2) presented the decline trend with the increase of height.After the typhoon passing through,the distribution of high levels of aerosol and HCHO stretched to about 1 kmand the abundances of the bottom layer were found as double higher than before,reaching 0.51 km^(−1) and 2.44 ppbv,while NO_(2) was still constrained within about 300 m with 2.59 ppbv in the bottom layer.The impacts of typhoon process forced air mass were also observed at the suburban site in Shanghai in view of both the aerosol extinction and chemical components.The different changes on air quality associated with typhoon and its mechanism in two different environments:coastal island and coastal city are worthy of further investigation as it frequent occurred in East Asia during summer and fall.

关键词： MAX-DOAS Aerosol optical depth Aerosol extinction coefficient Marine boundary layer Typhoon

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Progress in the preparation and physical properties of two-dimensional Cr-based chalcogenide materials and heterojunctions

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Frontiers of physics 2024年第2期19卷 105-130页

作者： Xiulian Fan ruifeng Xin Li Li Bo zhang Cheng Li Xilong Zhou Huanzhi Chen Hongyan zhang Fangping OuYang Yu Zhou School of Physics and Electronics Hunan Key Laboratory of Nanophotonics and DevicesCentral South UniversityChangsha 410083China Jincheng Research Institute of Opto-mechatronics Industry Jincheng 048000China Shanxi Key Laboratory of Advanced Semiconductor Optoelectronic Devices and Integrated Systems Jincheng 048000China School of Physical Science and Technology Xinjiang UniversityUrumqi 830046China State Key Laboratory of Powder Metallurgy Central South UniversityChangsha 410083China

Two-dimensional transition metal dichalcogenides(TMDs)exhibit promising application prospects in the domains of electronic devices,optoelectronic devices and spintronic devices due to their distinctive energy band structures and spin−orbit coupling properties.Cr-based chalcogenides with narrow or even zero bandgap,covering from semiconductors to metallic materials,have considerable potential for wide-band photodetection and two-dimensional magnetism.Currently,the preparation of 2D CrX_(n)(X=S,Se,Te)nanosheets primarily relies on chemical vapor deposition(CVD)and molecule beam epitaxy(MBE),which enable the production of high-quality large-area materials.This review article focuses on recent progress of 2D Cr-based chalcogenides,including unique crystal structure of the CrX_(n)system,phase-controlled synthesis,and heterojunction construction.Furthermore,a detailed introduction of room-temperature ferromagnetism and electrical/optoelectronic properties of 2D CrXn is presented.Ultimately,this paper summarizes the challenges associated with utilizing 2D Cr-based chalcogenides in preparation strategies,optoelectronics devices,and spintronic devices while providing further insights.

关键词： physical properties two-dimensional materials Cr-based chalcogenide controlled synthesis heterojunction eletronic and optoelectronic devices

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Rearranged 19-nor-7,8-seco-labdane diterpenoids and Diels-Alder cycloadducts from the Chinese liverwort Pallavicinia ambigua:Structural elucidation,photoinduced rearrangement,and cytotoxic activity

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Chinese Chemical Letters 2024年第3期35卷 415-418页

作者： Chunyang zhang Yuelan Li Zhaojun Chu Shuangzhi Yuan Yanan Qiao Jiaozhen zhang Lin Li Yueqing zhang ruifeng Tian Yajie Tang Hongxiang Lou Department of Natural Products Chemistry Key Lab of Chemical Biology(MOE)School of Pharmaceutical SciencesShandong UniversityJi'nan 250012China State Key Laboratory of Microbial Technology Shandong UniversityQingdao 266237China

Two distinctive rearranged 19-nor-7,8-seco-labdane diterpenoids(1 and 2)with a novel tetracyclo[5.***.1.0^(2,5.)0^(4,10)]decane skeleton,a derivative of the open tetrahydrofuran ring(7),three dimeric compounds(8-10),and four revised homologs(3-6)were obtained from Chinese liverwort Pallavicinia ambigua.Their structures were identified via combined analysis of their spectroscopic data,single-crystal X-ray diffraction patterns,and ECD calculations.The light-driven conversion of compound 5 to compounds 1-4 demonstrated that photochemically induced postmodification involved in biosynthesis is an important way to diversify natural structures.A preliminary cytotoxicity assay revealed that compound 5 showed significant inhibition in the human prostate cancer(PC-3)cell line via an apoptotic pathway.

关键词： Liverwort Pallavicinia ambigua 19-nor-7 8-seco-Labdan diterpenoid Photoinduced rearrangement Cytotoxic activity

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Divergent Synthesis of Organofluorinated Molecules from Titanium Mediated Deoxygenation of Free Alcohols

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Chinese Journal of Chemistry 2023年第15期41卷 1783-1790页

作者： Hongjun Tian ruifeng zhang Lei Shi Can Zha Xiaoming Wang State Key Laboratory of Organometallic Chemistry CenterforExcellence in Molecular SynthesisShanghai lnstitute of Organic Chemistry University of Chinese Academy of SciencesChinese Academy of Sciences345 Lingling RoadShanghai 200032China KeyLaboratory of Green ChemicalMedia and Reactions Ministryof EducationCollaborative Innovation Centerof Henan Provincefor Green Manufacturing of Fine ChemicalsHenan Key Laboratory of Organic Functional Molecules and Drug InnovationSchool of Chemistry and Chemical EngineeringHenan Normal UniversityXinxiangHenan 453007China school of Chemistry and Materials Science Hangzhou InstituteforAdvanced StudyUniversity of Chinese Academy of Sciences1 Sub-lane XiangshanHangzhouZhejiang 310024China

Comprehensive Summary Alcohols as among the most widely occurring organic compounds known,deoxygenative transformations of free alcohols as partners in radical addition reactions remain formidable challenges with great opportunities to achieve new and useful transformations.Herein,we report a protocol via C—O bond cleavage and C—C bond-forming reaction of trifluoromethyl alkenes with free alcohols assisted by titanium reagents via a deoxygenative radical strategy,enabling the divergent synthesis for functional-group-rich organofluorinated compounds in high efficiencies.In this transformation,tertiary alcohols by Ti-catalysis could be converted to trifluoromethyl alkanes without defluorination in acidic conditions,while benzyl alcohols are employed by Ti-mediated activation to supply the gem-difluoroalkenes with defluorination in the presence of a base.This protocol is applicable for a broad range of trifluoromethyl alkenes with good functional group tolerance and a variety of tertiary alcohols and benzyl alcohols(including primary。

关键词： Divergent synthesis Organofluorinated compounds Cross-coupling Titanium-mediated Alcohols Radical

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Resistance development,cross-resistance,and fitness costs associated with Aphis gossypii resistance towards sulfoxaflor and acetamiprid in different geographical regions

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Journal of Integrative Agriculture 2024年第7期23卷 2332-2345页

作者： Wei Wang Renfu zhang Haiyang Liu ruifeng Ding Qiushi Huang Ju Yao Gemei Liang Key Laboratory of Integrated Pest Management on Crop in Northwestern Oasis of Ministry of Agriculture and Rural Affairs Institute of Plant ProtectionXinjiang Academy of Agricultural SciencesUrumqi 830091China State Key Laboratory for Biology of Plant Diseases and Insect Pests Institute of Plant ProtectionChinese Academy of Agricultural SciencesBeijing 100193China

Aphis gossypii has become increasingly difficult to manage due to its strong insecticide resistance.In the laboratory,we established sulfoxaflor-resistant and acetamiprid-resistant strains in two A.gossypii populations with different basal insecticide resistance levels,and evaluated the effects of basal insecticide resistance on the resistance development and cross-resistance,as well as differences in fitness.Under the same selection pressure,Yarkant A.gossypii(with low basal insecticide resistance)evolved resistance to sulfoxaflor and acetamiprid more quickly than Jinghe A.gossypii(with high basal insecticide resistance),and the evolution of A.gossypii resistance to sulfoxaflor developed faster than acetamiprid in both Yarkant and Jinghe,Xingjiang,China.The sulfoxaflor-resistant strains selected from Yarkant and Jinghe developed significant cross-resistance to acetamiprid,imidacloprid,thiamethoxam and pymetrozine;while the acetamiprid-resistant strains developed significant cross-resistance to sulfoxaflor,imidacloprid,thiamethoxam,pymetrozine,and chlorpyrifos.The relative fitness of A.gossypii decreased as the resistance to sulfoxaflor and acetamiprid developed.The relative fitness levels of the sulfoxaflor-resistant strains(Yarkant-SulR and Jinghe-SulR)were lower than those of the acetamipridresistant strains(Yarkant-AceR and Jinghe-AceR).In addition,the relative fitness levels of sulfoxaflor-and acetamiprid-resistant strains were lower in Jinghe than in Yarkant.In summary,basal insecticide resistance of A.gossypii and insecticide type affected the evolution of resistance to insecticides in A.gossypii,as well as cross-resistance to other insecticides.The sulfoxaflor-and acetamiprid-resistant A.gossypii strains had obvious fitness costs.The results of this work will contribute to the insecticide resistance management and integrated management of A.gossypii.

关键词： Aphis gossypii sulfoxaflor acetamiprid cross-resistance fitness costs different sensitivities

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Hybrid Control Strategy for Air-conditioning Loads Participating in Peak Load Reduction Through Wide-range Transport Model

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Journal of Modern Power Systems and Clean Energy 2022年第6期10卷 1542-1551页

作者： Yunfeng Ma Zengqiang Mi ruifeng zhang Huowen Peng Yulong Jia School of Electrical&Electronic Engineering North China Electric Power UniversityBeijingChina Department of Electrical Engineering North China Electric Power UniversityBaodingChina University of Edinburgh Old CollegeSouth BridgeEdinburghEH89YLUK Planning&Design Institute at State Grid Integrated Energy Services Group Co. Ltd.Beijing 100032China

This paper proposes a hybrid control strategy of air-conditioning loads(ACLs)for participating in peak load reduction.The hybrid control strategy combines the temperature setpoint adjustment(TSA)control and on/off control together to make full use of response potentials of ACLs.The primary free transport model of ACLs has been established in literature at or near a fixed temperature setpoint.In this paper,a wide-range transport(WRT)model suitable for larger value of TSA is proposed.The WRT model can be constructed easily through the parameter of devices and indoor and outdoor temperature.To modulate the aggregate response characteristics of ACLs more friendly to the power grid,the safe protocol(SP)is adopted and integrated into the WRT model,which achieves a good unification of oscillation suppression and efficient modeling.Moreover,the hybrid control strategy is implemented based on the WRT model,and the model predictive control(MPC)controller is designed considering the tracking error and control switch cost.At last,the superiority of the hybrid control strategy is verified and the performance of ACLs for peak load reduction under this controller is simulated.The simulation results show that the hybrid control strategy could exploit the load reduction potential of ACLs fully than the TSA mode and track the reference signal more accurately.

关键词： Peak load reduction air conditioning load aggregate modeling response characteristics state space model model predictive control

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