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Interdecadal Variations of ENSO Impacts over the Indo-Northwest Pacific Region and the Related Mechanisms

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Journal of Meteorological Research 2024年第2期38卷 235-248页

作者： Hongxia LAN Jing MA haiming XU Jingjia LUO Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters(CIC-FEMD)/Key Laboratory of Meteorological Disaster Ministry of Education/Joint International Research Laboratory of Climate and Environment Change(KLME/ILCEC)Nanjing University of Information Science&TechnologyNanjing 210044 School of Atmospheric Sciences Nanjing University of Information Science&TechnologyNanjing 210044

Owing to limited observations,it remains unknown whether the impact of El Niño-Southern Oscillation(ENSO)on the Indian Ocean-Northwest Pacific(IO-NWP)climate showed decadal changes in the early 20th century.Using multi-source reanalysis and hindcast datasets from the ECMWF and NOAA extending back to 1901,this study investigates interdecadal variations of the impact of ENSO on the IO-NWP climate from 1901 to 2009.It is found that the influence of ENSO on the IO-NWP climate shows“strong-weak-strong”interdecadal change during 1901-2009.This is characterized by much weaker Indian Ocean sea surface temperature(SST)warming and a weaker NWP subtropical anticyclone(NWPSA)in the following summer of El Ni?o during 1946-1967,compared with those in the other two periods(1901-1945 and 1968-2009).Analyses of the datasets indicate that the interdecadal variation is mainly associated with the change in ENSO amplitude.In contrast to the period of 1946-1967,a greater SST variance occurred in the central-eastern equatorial Pacific during 1901-1945 and 1968-2009.A stronger El Ni?o tends to generate more significant anticyclonic anomalies over the southeast Indian Ocean through teleconnection.The northwesterly anomalies to the south of the anticyclone weaken the southeast trade winds and warm the south Indian Ocean SST via wind-evaporation-SST feedback,and the positive south Indian Ocean SST anomalies trigger westward-propagating oceanic Rossby waves to induce stronger warming of the southwest Indian Ocean,leading to a significant asymmetric wind pattern across the equator in spring.The profound northeastward winds on the north side weaken the southwest monsoon,leading to a“second warming”over the north Indian Ocean in summer,which anchors the eastward-propagating warm Kelvin waves and results in a stronger NWPSA by inducing surface divergence and suppressing deep convection.

关键词： ENSO Indo-Northwest Pacific Northwest Pacific subtropical anticyclone decadal changes

Geometry characteristics and wide temperature behavior of silicon-based GaN surface acoustic wave resonators with ultrahigh quality factor

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Science China(Information Sciences) 2024年第2期67卷 267-278页

作者： Guofang YU Renrong LIANG haiming ZHAO Lei XIAO Jie CUI Yue ZHAO Wenpu CUI Jing wang Jun XU Jun FU Tianling REN School of Integrated Circuits Tsinghua University Beijing National Research Center for Information Science Technology Tsinghua University

Surface acoustic wave(SAW) resonators with an ultrahigh Q-factor are designed and fabricated on silicon-based gallium nitride(GaN/Si). The temperature-dependent performance is characterized over a wide range, from 10 to 500 K. Finite element analysis is employed to guide the design of the SAW resonator from indications of the Rayleigh mode and weak propagation direction dependence of SAW in the c-plane of GaN/Si. The SAW resonator with 100 pairs of interdigital transducers(IDT), 100 pairs of grating reflectors(GR) for each side, aperture size of 80 μm, metallization ratio of 0.5, and electrode width of 500 nm resonates at 1.9133 GHz accordingly with an ultrahigh Q-factor of 7622 at room temperature, which contributes the fr× Qr, up to 14.583×1012Hz. A resonator operating over 10 to 500 K indicates an approximately linear decreasing temperature dependence above 280 K while being approximately constant below 40 K. The fitting to resonator characteristics using the modified Butterworth Van Dyke(m BVD) model reveals a reduction in both the electrode and mechanical losses while worsening the dielectric loss with cooling down.

关键词： GaN/Si SAW resonator ultrahigh Q-factor temperature-dependent performance mBVD losses

The frontier of microplastics and nanoplastics: Soil health and carbon neutrality

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Pedosphere 2023年第1期33卷 11-13页

作者： Zhuanxi LUO Aoze LI haiming wang Baoshan XING College of Chemical Engineering Huaqiao UniversityXiamen 361021China Stockbridge School of Agriculture University of MassachusettsAmherst MA 01003USA

Microplastics and nanoplastics(MNPs)in soil have drawn increasing concerns about their potential threats to soil ecosystems due to their ubiquitous occurrence and persistence.The interactions of MNPs with soil components,microbial community,plants,and fauna determine their impacts on soil biogeochemical processes and food security.However,they are not largely explored.Further research is also needed to develop reliable and standardized techniques and methods to characterize the relevant MNPs interacting with different types of soil ecosystems and to deeply examine their impacts on soil health,food security,and climate changes.In addition,mitigation protocols and regulation guidelines need to be developed.New findings will provide scientific and technological support for the understanding and management of soil health and carbon neutrality as influenced by MNPs.

关键词： soil neutral frontier

Luminescent metal-halide perovskites:fundamentals,synthesis,and light-emitting devices

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Science China Chemistry 2024年第6期67卷 1776-1838页

作者： Kang wang Jeong Hui Kim Jie Yang Xiaoke Liu Yixuan Dou Yuxuan Li Weijian Tao Haiyun Dong haiming Zhu Kaifeng Wu Li Na Quan Feng Gao Jianpu wang Letian Dou Yong Sheng Zhao Beijing National Laboratory for Molecular Sciences(BNLMS) Key Laboratory of PhotochemistryInstitute of ChemistryChinese Academy of SciencesBeijing100190China Davidson School of Chemical Engineering Purdue UniversityWest LafayetteIN47907USA School of Chemical Sciences University of Chinese Academy of SciencesBeijing100049China Key Laboratory of Flexible Electronics(KLOFE) Institute of Advanced Materials(IAM)&School of Flexible Electronics(Future Technologies)Nanjing Tech University(NanjingTech)Nanjing211816China Department of Physics Linköping UniversityLinköping58183Sweden Department of Chemistry Virginia TechBlacksburgVA24060USA State Key Laboratory of Molecular Reaction Dynamics Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian116023China Department of Chemistry Zhejiang UniversityHangzhou310058China Changzhou University Changzhou213164China Department of Chemistry Purdue UniversityWest LafayetteIN47907USA

Metal-halide perovskites have garnered considerable research attention as highly efficient light emitters in recent years due to their outstanding optoelectronic properties with remarkable tunability and excellent solution processabilities.Substantial advancements have been achieved in the development of novel halide perovskites,and the exploitations of these materials in lightemitting devices.This review comprehensively outlines recent breakthroughs in metal-halide perovskites,encompassing the rational design of perovskite materials with tunable light emission properties,the controllable growth of single crystal for a deeper understanding of their structure-property relationships,as well as the fundamental insights into the photophysics and carrier dynamics in perovskite systems.Additionally,it provides an overview of recent applications of perovskite materials in high-performance light-emitting diodes(LEDs)and lasers.

关键词： metal-halide perovskites perovskite luminescent materials perovskite synthesis excited-state processes perovskite light-emitting diodes perovskite lasers

Ensemble-transfer-learning-based channel parameter prediction in asymmetric massive MIMO systems

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Frontiers of Information Technology & Electronic Engineering 2023年第2期24卷 275-288页

作者： Zunwen HE Yue LI Yan ZHANG Wancheng ZHANG Kaien ZHANG Liu GUO haiming wang School of Information and Electronics Beijing Institute of TechnologyBeijing100081China State Key Laboratory of Millimeter Waves Southeast UniversityNanjing210096China

Asymmetric massive multiple-input multiple-output(MIMO)systems have been proposed to reduce the burden of data processing and hardware cost in sixth-generation mobile networks(6G).However,in the asymmetric massive MIMO system,reciprocity between the uplink(UL)and downlink(DL)wireless channels is not valid.As a result,pilots are required to be sent by both the base station(BS)and user equipment(UE)to predict doubledirectional channels,which consumes more transmission and computational resources.In this paper we propose an ensemble-transfer-learning-based channel parameter prediction method for asymmetric massive MIMO systems.It can predict multiple DL channel parameters including path loss(PL),multipath number,delay spread(DS),and angular spread.Both the UL channel parameters and environment features are chosen to predict the DL parameters.Also,we propose a two-step feature selection algorithm based on the SHapley Additive exPlanations(SHAP)value and the minimum description length(MDL)criterion to reduce the computation complexity and negative impact on model accuracy caused by weakly correlated or uncorrelated features.In addition,the instance transfer method is introduced to support the prediction model in new propagation conditions,where it is difficult to collect enough training data in a short time.Simulation results show that the proposed method is more accurate than the back propagation neural network(BPNN)and the 3GPP TR 38.901 channel model.Additionally,the proposed instancetransfer-based method outperforms the method without transfer learning in predicting DL parameters when the beamwidth or the communication sector changes.

关键词： Asymmetric massive multiple-input multiple-output(MIMO)system Channel model Ensemble learning Instance transfer Parameter prediction

Structural characterization and prebiotic potential of polysaccharides from Polygonatum sibiricum

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Food Science and Human Wellness 2024年第4期13卷 2208-2220页

作者： Zihan Qi Tiexiang Gao Jingjing Li Shuhan Zhou Zhigang Zhang Mingzhu Yin haiming Hu Hongtao Liu College of Basic Medical Sciences Hubei University of Chinese MedicineWuhan 430065China College of Pharmacy Hubei University of Chinese MedicineWuhan 430065China

Polygonatum sibiricum has been widely used due to its excellent biological activities.We prepared a novel polysaccharide from P.sibiricum(PSP)in this study.According a monosaccharide composition analysis,PSP was mainly composed of fructose and glucose with a molar percentage of 93.81:5.12.The main linkage types were identified asα-D-Glcp-1→and→2-β-D-Fruf-1→.The molecular weight of PSP showed no significant change after simulated salivary and gastrointestinal digestion.However,PSP could be broken down by intestinal bacteria.Our findings revealed that PSP administration increased the abundance of probiotics such as Bifidobacterium.Furthermore,the results showed that gut microbes could utilize PSP to produce short-chain fatty acids including acetic acid,propionic acid,and butyric acid.Also,the PSP fermentation broth displayed an excellent scavenging effect on free radicals,including 2,2-diphenyl-1-picrylhydrazyl radical,superoxide radical,and hydroxyl radical.In summary,this study will help to promote the application of PSP as prebiotics in functional food and the medical industry.

关键词： Dietary polysaccharides Prebiotic Gut microbiota Short-chain fatty acids

Systemic low-grade inflammation associated with specific depressive symptoms:insights from network analyses of five independent NHANES samples

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General Psychiatry 2024年第2期37卷 284-288页

作者： Jingyu Lin haiming Huang Tianmei Si Lin Chen Jingxu Chen Yun-Ai Su Beijing Huilongguan Hospital BeijingChina Department of Clinical Laboratory Peking University First HospitalBeijingChina Neuropsychopharmacology Peking University Institute of Mental HealthBeijingChina National Clinical Research Center for Mental Disorders BeijingChina

To the editor:Major depressive disorder(MDD)is a heterogeneous disorder with varying symptom presentations and underlying biological mechanisms.1 The mainstream neurobiological hypotheses of depression involve monoami... 详细信息

关键词： inflammation depress pituitary

Gas-phase synthesis of Ti_(2)CCl_(2) enables an efficient catalyst for lithiumsulfur batteries

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The Innovation 2024年第1期5卷 33-40页

作者： Maoqiao Xiang Zihan Shen Jie Zheng Miao Song Qiya He Yafeng Yang Jiuyi Zhu Yuqi Geng Fen Yue Qinghua Dong Yu Ge Rui wang Jiake Wei Weiliang wang haiming Huang Huigang Zhang Qingshan Zhu Chuanfang John Zhang State Key Laboratory of Multiphase Complex Systems Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China School of Chemical Engineering University of the Chinese Academy of SciencesBeijing 100049China Innovation Academy for Green Manufacture Chinese Academy of SciencesBeijing 100190China China Nuclear Power Engineering Co. Ltd.117 West Third Ring RoadNorth SectionBeijing 100840China College of Materials Science&Engineering Sichuan UniversityChengdu 610065China State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China School of Physics Guangdong Province Key Laboratory of Display Material and TechnologyCenter for Neutron Science and TechnologySun Yat-sen UniversityGuangzhou 510275China Solid State Physics&Material Research Laboratory School of Physics and Materials ScienceGuangzhou UniversityGuangzhou 510006China

MXenes have aroused intensive enthusiasm because of their exotic properties and promising applications.However,to date,they are usually synthesized by etching technologies.Developing synthetic technologies provides more opportunities for innovation and may extend unexplored applications.Here,we report a bottom-up gas-phase synthesis of Cl-terminated MXene(Ti_(2)CCl_(2)).The gas-phase synthesis endows Ti_(2)CCl_(2) with unique surface chemistry,high phase purity,and excellent metallic conductivity,which can be used to accelerate polysulfide conversion kinetics and dramatically prolong the cyclability of Li-S batteries.In-depth mechanistic analysis deciphers the origin of the formation of Ti_(2)CCl_(2) and offers a paradigm for tuning MXene chemical vapor deposition.In brief,the gas-phase synthesis transforms the synthesis of MXenes and unlocks the hardly achieved potentials of MXenes.

关键词： synthesis phase lithium

Using Natural Radionuclides to Trace Sources of Suspended Particles in the Lower Reaches of the Yellow River

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Journal of Ocean University of China 2024年第1期23卷 99-108页

作者： ZHANG Han BURNETT CWilliam ZHANG Xiaojie ZHAO Shibin YANG Disong NAN haiming YU Zhigang XU Bochao Frontiers Science Center for Deep Ocean Multispheres and Earth System and Key Laboratory of Marine Chemistry Theory and TechnologyMinistry of EducationOcean University of ChinaQingdao 266100China Laboratory for Marine Ecology and Environmental Science Qingdao National Laboratory for Marine Science and TechnologyQingdao 266071China College of Chemistry and Chemical Engineering Ocean University of ChinaQingdao 266100China Department of Earth Ocean and Atmospheric ScienceFlorida State UniversityTallahasseeFL 32306USA North China Sea Environmental Monitoring Center State Oceanic AdministrationKey Laboratory of Ecological Prewarning and Protection of Bohai SeaMNRQingdao 266033China Shandong Provincial Key Laboratory of Marine Ecological Environment and Disaster Prevention and Mitigation Qingdao 266033China

Natural radionuclides are powerful tools for understanding the sources and fate of suspended particulate matter(SPM).Particulate matter with different particle sizes behaves differently with respect to adsorption and desorption.We analyzed the activi-ties and distribution characteristics of multiple natural radionuclides(238U,226Ra,40K,228Ra,7Be and 210Pbex)on size-fractionated SPM at the Lijin Hydrographic Station(Huanghe or Yellow River)every month over a one-year period.Results showed that medium silt(16–32µm)was the main component.As expected,the activity of each radionuclide decreased with an increase of particle size.We examined the sources of SPM with different particle sizes using activity ratios of 226Ra/238U,228Ra/226Ra,40K/238U and 7Be/210Pbex,and concluded that SPM with different particle sizes originated from different sources.Our results indicate that fine SPM(32µm)was mainly derived from resuspension of riverbed sediment.During high runoff periods,the concentration of SPM increased significantly,and the pro-portion of fine particles originating upstream increased.Naturally occurring radioactive isotopes,especially on size-fractionated par-ticles,are therefore seen as useful tracers to understand the sources and behaviors of riverine particles transported from land to sea.

关键词： the Yellow River suspended particulate matter size-fractions radionuclides sediment sources water elutriator