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Chinese Journal of Chemical Engineering 2024年第5期69卷 212-219页

作者： Guangxia jin Yuxue wu Feng Wei School of Biological and Chemical Engineering NingboTech UniversityNingbo 315100China

The isolation of minor components from complex natural product matrices presents a significant challenge in the field of purification science due to their low concentrations and the presence of structurally similar *** study introduces an optimized twin-column recycling chromatography method for the efficient and simultaneous purification of these elusive *** introducing water at a small flowing rate between the twin columns,a step solvent gradient is created,by which the leading edge of concentration band would migrate at a slower rate than the trailing edge as it flowing from the upstream to downstream ***,the band broadening is counterbalanced,resulting in an enrichment effect for those minor components in separation ***,two target substances,which showed similar peak position in high performance liquid chromatography(HPLC)and did not exceed 1.8%in crude paclitaxel were selected as target compounds for *** using the twin-column recycling chromatography with a step solvent gradient,a successful purification was achieved in getting the two with the purity almost 100%.We suggest this method is suitable for the separation of most components in natural produces,which shows higher precision and recovery rate compared with the common lab-operated separation ways for natural products(thin-layer chromatography and prep-HPLC).

关键词： Solvent gradient Twin-column recycling chromatography Purification Minor component Natural products

Synergistic Interdecadal Evolution of Precipitation over Eastern China and the Pacific Decadal Oscillation during 1951-2015

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Advances in Atmospheric Sciences 2024年第1期41卷 53-72页

作者： Minmin wu rong-Hua ZHANG Junya HU Hai ZHI Key Laboratory of Ocean Circulation and Waves Institute of OceanologyChinese Academy of SciencesQingdao 266071China School of Marine Sciences Nanjing University of Information Science and TechnologyNanjing 210044China Laosan Laboratory Qingdao 266237China School of Atmospheric Sciences Nanjing University of Information Science and TechnologyNanjing 210044China University of Chinese Academy of Sciences Beijing 100029China

By using the multi-taper method(MTM)of singular value decomposition(SVD),this study investigates the interdecadal evolution(10-to 30-year cycle)of precipitation over eastern China from 1951 to 2015 and its relationship with the North Pacific sea surface temperature(SST).Two significant interdecadal signals,one with an 11-year cycle and the other with a 23-year cycle,are identified in both the precipitation and SST *** show that the North Pacific SST forcing modulates the precipitation distribution over China through the effects of the Pacific Decadal Oscillation(PDO)-related anomalous Aleutian low on the western Pacific subtropical high(WPSH)and Mongolia high(MH).During the development stage of the PDO cold phase associated with the 11-year cycle,a weakened WPSH and MH increased the precipitation over the Yangtze River Basin,whereas an intensified WPSH and MH caused the enhanced rain band to move northward to North China during the decay *** the development stage of the PDO cold phase associated with the 23-year cycle,a weakened WPSH and MH increased the precipitation over North China,whereas an intensified WPSH and the weakened MH increased the precipitation over South China during the decay *** 11-year and 23-year variabilities contribute differently to the precipitation variations in the different regions of China,as seen in the 1998flooding *** 11-year cycle mainly accounts for precipitation increases over the Yangtze River Basin,while the 23-year cycle is responsible for the precipitation increase over Northeast *** results have important implications for understanding how the PDO modulates the precipitation distribution over China,helping to improve interdecadal climate prediction.

关键词： MTM-SVD PDO SST anomalies interdecadal variability precipitation over China

Research on modeling and self-excited vibration mechanism in magnetic levitation-collision interface coupling system

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Applied Mathematics and Mechanics(English Edition) 2024年第5期45卷 873-890页

作者： jinghu TANG Chaofeng LI jin ZHOU Zhiwei wu School of Mechanical Engineering&Automation Northeastern UniversityShenyang 110819China Key Laboratory of Vibration and Control of Aero-Propulsion Systems of Ministry of Education of China Northeastern UniversityShenyang 110819China School of Mechanical and Electrical Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China

The modeling and self-excited vibration mechanism in the magnetic levitation-collision interface coupling system are *** effects of the control and interface parameters on the system's stability are *** frequency range of self-excited vibrations is investigated from the energy point of *** phenomenon of self-excited vibrations is elaborated with the phase *** corresponding control strategies are briefly analyzed with respect to the vibration *** results show that when the levitation objects collide with the mechanical interface,the system's vibration frequency becomes larger with the decrease in the collision gap;when the vibration frequency exceeds the critical frequency,the electromagnetic system continues to provide energy to the system,and the collision interface continuously dissipates energy so that the system enters the self-excited vibration state.

关键词： magnetic levitation coupling system self-excited vibration mechanical interface vibration frequency

Market-based solution in China to finance the clean from the dirty

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Fundamental Research 2024年第2期4卷 324-333页

作者： Haoqi Qian rong Ma Libo wu Institute for Global Public Policy Fudan UniversityShanghai 200433China LSE-Fudan Research Centre for Global Public Policy Fudan UniversityShanghai 200433China School of Economics Fudan UniversityShanghai 200433China Shanghai Institute for Energy and Carbon Neutrality Strategy Fudan UniversityShanghai 200433China

Financial incentives play a key role in promoting renewable energy investments that can help China achieve the‘dual carbon’*** national emissions trading scheme(ETS)and the renewable energy portfolio standard(RPS)are two existing market-based policy instruments that can generate stable expected returns for low-carbon *** paper studies the interactive distribution effects of these two market-based *** use the micro-level thermal power plant data to investigate the abatement effects of the national ETS,in which the details show that the existing rate-based ETS will result in higher negative impacts on power units,whose installed capacities are smaller than 400 *** interactive distribution effects between the two markets will occur when the permit allocation standards of the national ETS become stricter than the existing *** in Eastern China and Northern China will face high pressure on costs in both ETS and RPS *** the levels of the permit allocation standards are set as 70%of the existing ones and the carbon price is assumed to be 200 yuan/ton in 2030,the annual market size of the national ETS will be nearly 100 billion yuan,and the annual market size is predicted to be 250 billion *** the existing rate-based national ETS,the China Certified Emission Reduction(CCER)mechanism will have an offsetting effect,which should be taken into serious consideration during the policy-making processes in the future.

关键词： Emission trading scheme Renewable energy portfolio standard Green finance Policy interactions China certified emission reduction Distribution effect

Dietary inflammatory index and its impact on severity and recurrence of Tourette syndrome in children

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World Journal of Psychiatry 2024年第8期14卷 1208-1215页

作者： Xiao-Ping wu rong-rong Fang Ting-Ting Ji Department of Pediatrics Qingdao Chengyang People’s HospitalQingdao 266109Shandong ProvinceChina

BACKGROUND Tourette syndrome(TS)is a neurodevelopmental disorder characterized by the presence of motor and vocal tics,typically beginning in *** signifi-cant research efforts,the exact pathophysiology of TS remains incompletely *** studies suggest that inflammation may play a role in the severity and progression of TS,pointing to the potential influence of dietary and lifestyle factors on the ***,research on the specific connection between dietary inflammatory index(DII)and TS is still in its early stages,requir-ing additional clinical and epidemiological studies to validate the strength and specific mechanisms of this *** A total of 207 children diagnosed with TS in the pediatric department of Qingdao Chengyang People’s Hospital from January 2022 to January 2023 were *** were divided into stable and unstable groups based on follow-up *** enrollment,general information of the children[age,gender,body mass index(BMI),guardian’s education level,DII score,medical history,family history,academic stress,electronic device usage,medication,and disease progression]was assessed,and serum inflammatory levels were measured during follow-up *** scores and Yale Global Tic Severity Scale(YGTSS)scores were ***,based on YGTSS scores,the children were classified into mild,moderate,and severe *** DII,interleukin-6(IL-6),C-reactive protein(CRP),and tumor necrosis factor-alpha(TNF-α)levels in each group were *** Follow-up surveys were completed by 207 children and their *** them,117 children were in the stable group,and 90 were in the recurrent *** found no statistically significant differences in age,gender,comorbidities,BMI,and disease duration between the two groups(P>0.05).However,academic stress,electronic device usage,medication,guardian’s education level,and DII scores showed statistically significant differences between the groups(P

关键词： Dietary inflammation index Tourette's syndrome Correlation analysis Pro-inflammatory foods Inflammation levels Impact on severity and recurrence

Counteracting effects on ENSO induced by ocean chlorophyll interannual variability and tropical instability wave-scale perturbations in the tropical Pacific

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Science China Earth Sciences 2024年第2期67卷 387-404页

作者： rong-Hua ZHANG Feng TIAN Qidong SHI Xiujun WANG Tongwen wu School of Marine Sciences Nanjing University of Information Science and TechnologyNanjing210044China Laoshan Laboratory Qingdao266237China Key Laboratory of Ocean Circulation and Waves Institute of OceanologyChinese Academy of SciencesQingdao266071China University of Chinese Academy of Sciences Beijing101408China Faculty of Geographical Sciences Beijing Normal UniversityBeijing100875China Earth System Modeling and Prediction Centre China Meteorological AdministrationBeijing100081China

Large perturbations in chlorophyll(Chl)are observed to coexist at interannual and tropical instability wave(TIW)scales in the tropical Pacific;at present,their combined effects on El Ni?o-Southern Oscillation(ENSO)through ocean biologyinduced heating(OBH)feedbacks are not understood ***,a hybrid coupled model(HCM)for the atmosphere and ocean physics-biogeochemistry(AOPB)in the tropical Pacific is adopted to quantify how ENSO can be modulated by Chl perturbations at interannual and TIW scales,individually or collectively,*** HCM-based sensitivity experiments demonstrate a counteracting effect on ENSO:the bio-climate feedback due to large-scale Chl interannual variability acts to damp ENSO through its impact on upper-ocean stratification and vertical mixing,whereas that due to TIW-scale Chl perturbations tends to amplify *** ENSO simulations are sensitively dependent on the ways Chl effects are represented at these different scales,it is necessary to adequately take into account these related differential Chl effects in climate modeling.A bias source for ENSO simulations is illustrated that is related with the Chl effects in the tropical Pacific,adding in a new insight into interactions between the climate system and ocean ecosystem on different scales in the *** results reveal a level of complexity of ENSO modulations resulting from Chl effects at interannual and TIW scales,which are associated with ocean biogeochemical processes and their interactions with physical processes in the tropical Pacific.

关键词： Ocean chlorophyll Bio-climate feedbacks Interannual variability Tropical instability waves Counteracting effects A hybrid coupled model

Identification of high oxygen-consuming substances in stormwater drainage systems illicitly connected with sewage system

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Journal of Environmental Sciences 2024年第4期138卷 132-140页

作者： Chen Xu Zuxin Xu Wenhai Chu Shanshan wu rong Xiao Lei Su State Key Laboratory of Pollution Control and Resource Reuse College of Environmental Science and EngineeringTongji UniversityShanghai 200092China Ministry of Education Key Laboratory of Yangtze River Water Environment Tongji UniversityShanghai 200092China Guangzhou Resource Environmental Protection Technology Co. Ltd.Guangzhou 510030China

The dissolved oxygen content in water is an important indicator for assessing the quality of the water environment,and maintaining a certain amount of dissolved oxygen is essential for the healthy development of the ecological *** a water body is anoxic,the activity of anaerobic microorganisms increases and organic matter is decomposed to produce a large number of blackening and odorizing substances,resulting in black and odorous water bodies,which is a very common and typical phenomenon in ***,there is still a relatively universal occurrence of illicitly connected stormwater and sewage pipes in the urban drainage pipe network in China,which makes oxygen-consuming substances be directly discharged into rivers through stormwater pipes and consume the dissolved oxygen in the water bodies,resulting in an oxygen deficiency of the *** induces seasonal or year-round black and stink phenomena in urban ***,identifying high oxygen-consuming substances,which lays the foundation for the subsequent removal of oxygen-consuming substances,is *** a series of comparisons of water quality indicators and analysis of organic characteristics,it was found that the oxygen consumption capacity of domestic sewage was higher than that of industrial wastewater in the selected area of this study,and the oxygen-consuming substances of domestic sewage were small molecular amino *** comparing 20 conventional free amino acids,it was found that seven of them consumed oxygen easily,and compared with chemical oxygen consumption,biological oxygen consumption was in a leading position.

关键词： Urban drainage system Oxygen-consuming substances Domestic sewage Amino acid

Microwave shock motivating the Sr substitution of 2D porous GdFeO_(3) perovskite for highly active oxygen evolution

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Journal of Energy Chemistry 2024年第1期88卷 232-241,I0006页

作者： jinglin Xian Huiyu Jiang Zhiao wu Huimin Yu Kaisi Liu Miao Fan rong Hu Guangyu Fang Liyun Wei jingyan Cai Weilin Xu Huanyu jin Jun Wan State Key Laboratory of New Textile Materials and Advanced Processing Technologies Hubei Key Laboratory of Biomass Fibers and Eco-Dyeing&FinishingWuhan Textile UniversityWuhan 430200HubeiChina Future Industries Institute STEMUniversity of South AustraliaAdelaideSA 5095Australia Institute for Sustainability Energy and ResourcesThe University of AdelaideAdelaideSA 5005Australia

The incorporation of partial A-site substitution in perovskite oxides represents a promising strategy for precisely controlling the electronic configuration and enhancing its intrinsic catalytic *** methods for A-site substitution typically involve prolonged high-temperature *** these processes promote the development of unique nanostructures with highly exposed active sites,they often result in the uncontrolled configuration of introduced ***,we present a novel approach for synthesizing two-dimensional(2D)porous GdFeO_(3) perovskite with A-site strontium(Sr)substitution utilizing microwave shock *** technique enables precise control of the Sr content and simultaneous construction of 2D porous structures in one step,capitalizing on the advantages of rapid heating and cooling(temperature~1100 K,rate~70 K s^(-1)).The active sites of this oxygen-rich defect structure can be clearly revealed through the simulation of the electronic configuration and the comprehensive analysis of the crystal *** electrocatalytic oxygen evolution reaction application,the synthesized 2D porous Gd_(0.8)Sr_(0.2)FeO_(3) electrocatalyst exhibits an exceptional overpotential of 294 mV at a current density of 10 mA cm^(-2)and a small Tafel slope of 55.85 mV dec^(-1)in alkaline *** study offers a fresh perspective on designing crystal configurations and the construction of nanostructures in perovskite.

关键词： 2D materials Perovskite Microwave Electrocatalysis Oxygen evolution reaction

Carbon-based interface engineering and architecture design for high-performance lithium metal anodes

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Carbon Energy 2024年第1期6卷 207-235页

作者： Na Zhu Yuxiang Yang Yu Li Ying Bai Junfeng rong Chuan wu SINOPEC Research Institute of Petroleum Processing Co. Ltd.BeijingChina Beijing Key Laboratory of Environmental Science and Engineering School of Materials Science and EngineeringBeijing Institute of TechnologyBeijingChina Yangtze Delta Region Academy of Beijing Institute of Technology JiaxingChina

Metallic lithium(Li)is considered the“Holy Grail”anode material for the nextgeneration of Li batteries with high energy density owing to the extraordinary theoretical specific capacity and the lowest negative electrochemical ***,owing to inhomogeneous Li-ion flux,Li anodes undergo uncontrollable Li deposition,leading to limited power output and practical *** materials and their composites with controllable structures and properties have received extensive attention to guide the homogeneous growth of Li to achieve high-performance Li *** this review,the correlation between the behavior of Li anode and the properties of carbon materials is ***,we review emerging strategies for rationally designing high-performance Li anodes with carbon materials,including interface engineering(stabilizing solid electrolyte interphase layer and other functionalized interfacial layer)and architecture design of host carbon(constructing three-dimension structure,preparing hollow structure,introducing lithiophilic sites,optimizing geometric effects,and compositing with Li).Based on the insights,some prospects on critical challenges and possible future research directions in this field are *** is anticipated that further innovative works on the fundamental chemistry and theoretical research of Li anodes are needed.

关键词： carbon materials dendrites hosts interfacial layers Li metal anodes

Electrostatic generator enhancements for powering IoT nodes via efficient energy management

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Microsystems & Nanoengineering 2024年第2期10卷 143-152页

作者： Zibo wu Zeyuan Cao Junchi Teng rong Ding Jiani Xu Xiongying Ye State Key Laboratory of Precision Measurement Technology and Instruments Department of Precision InstrumentTsinghua University100084BeijingChina

Electrostatic generators show great potential for powering widely distributed electronic devices in Internet of Things(IoT)***,a critical issue limiting such generators is their high impedance mismatch when coupled to electronics,which results in very low energy utilization ***,we present a high-performance energy management unit(EMU)based on a spark-switch tube and a buck converter with an RF *** optimizing the elements and parameters of the EMU,a maximum direct current output power of 79.2 mW m^(-2)rps^(-1)was reached for a rotary electret generator with the EMU,achieving 1.2 times greater power output than without the ***,the maximum power of the contact-separated triboelectric nanogenerator with an EMU is 1.5 times that without the *** excellent performance is attributed to the various optimizations,including utilizing an ultralow-loss spark-switch tube with a proper breakdown voltage,adding a matched input capacitor to enhance available charge,and incorporating an RF inductor to facilitate the high-speed energy transfer *** on this extremely efficient EMU,a compact self-powered wireless temperature sensor node was demonstrated to acquire and transmit data every 3.5 s under a slight wind speed of 0.5 m/*** work greatly promotes the utilization of electrostatic nanogenerators in practical applications,particularly in IoT nodes.

关键词： IoT power generator