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Effects of different water levels on phytoplankton in the Harbin section of the Songhua River

Journal of Oceanology and limnology 2025年第1期43卷 134-146页

作者： Yi’nan sun Jingshen li Yawen FAN Xinxin LU College of life Science and Technology Harbin Normal UniversityHarbin 150025China Key Laboratory of Aquatic Organisms Harbin Normal UniversityHarbin 150025China

The functional diversity index of a phytoplankton body has gradually become a new mean of measuring and *** explore the response of phytoplankton taxonomy and the functional diversity index to interannual environmental changes,a survey on the structure of the phytoplankton community and water physicochemical characteristics of the water was carried out at 28 sampling points in the Harbin section of the Songhua River for three consecutive years in every May from 2021 to *** taxonomy diversity index and the functional diversity index were ***,The relationship between the structure of the characteristics of the community and environmental factors was explored;secondly,we reveal the responses of taxonomic and functional diversity indices to different habitats between years;finally,we explore the main environmental factors that control the taxonomic and functional diversity indices of *** show that,initially,environmental factors in water changes caused by different water levels between years affected the composition of phytoplankton ***,by comparing the taxonomic diversity index and the functional diversity index on a time scale,we found that the taxonomic diversity index was more responsive to environmental ***,the main environmental factors on the phytoplankton taxonomic diversity index were dissolved oxygen,Taxonomic diversity index,and specific conductivity,and the main environmental factors that affected the functional diversity index were dissolved oxygen,turbidity,and water *** study reveals the important role of the taxonomic diversity index in river water quality evaluation,obtained new information on the relative precision of the taxonomic diversity index and the functional diversity index in the evaluation of ecological health of the water,and provided a reliable tool for monitoring river water quality based on aquatic organisms.

关键词： Songhua River Basin phytoplankton functional diversity biodiversity index watershed ecology

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Heterogeneous interface enhanced polyurethane/MXene@Fe_(3)O_(4)composite elastomers for electromagnetic wave absorption and thermal conduction

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International Journal of Minerals,Metallurgy and Materials 2025年第3期32卷 728-737页

作者： Xin An Zhaoxu sun Jiahui Shen Jiajia Zheng Aixi sun Xiping li Shaohua Jiang Yiming Chen Key Laboratory of Urban Rail Transit Intelligent Operation and Maintenance Technology&Equipment of Zhejiang Province College of EngineeringZhejiang Normal UniversityJinhua 321004China Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources International Innovation Center for Forest Chemicals and MaterialsCollege of Materials Science and EngineeringNanjing Forestry UniversityNanjing 210037China

The development of high-performance functional composites has become a research hotspot in response to the hazards of over-heating and electromagnetic radiation in modern electronic ***,we grew magnetic Fe_(3)O_(4)particles in situ on the MXene layer to obtain an MXene@Fe_(3)O_(4)composite with rich heterogeneous *** to the unique heterostructure and the synergistic effects of multiple electromagnetic wave absorption mechanisms,the composite achieved a minimum reflection loss of-27.14 dB and an effect-ive absorption bandwidth of 2.05 GHz at an absorption thickness of 2 ***,the MXene@Fe_(3)O_(4)composite could be encapsu-lated in thermoplastic polyurethane(TPU)via thermal *** obtained composite elastomer exhibited a strong tensile strength,and its thermal diffusivity was 113%higher than that of pure *** additional mechanical properties and thermal conduction features render this composite elastomer an advanced electromagnetic absorber to adapt to the ever-changing environment for expanding practical applications.

关键词： composite elastomer MXene electromagnetic wave absorption thermal conduction

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Recent advancements in noble-metal electrocatalysts for alkaline hydrogen evolution reaction

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Chinese Chemical Letters 2025年第1期36卷 176-200页

作者： Guoliang Gao Guangzhen Zhao Guang Zhu Bowen sun Zixu sun Shunli li Ya-Qian Lan Key Laboratory of Spin Electron and nanomaterials of Anhui Higher Education Institutes Suzhou UniversitySuzhou 234000China Key Laboratory for Special Functional Materials of Ministry of Education School of Materials Science and EngineeringHenan UniversityKaifeng 475004China School of Chemistry South China Normal UniversityGuangzhou 510006China

Available online Alkaline water electrolysis(AWE)is a prominent technique for obtaining a sustainable hydrogen source and effectively managing the energy *** metal-based electrocatalysts,owing to their exceptional hydrogen binding energy,exhibit remarkable catalytic activity and long-term stability in the hydrogen evolution reaction(HER).However,the restricted accessibility and exorbitant cost of noble-metal materials pose obstacles to their extensive adoption in industrial *** review investigates strategies aimed at reducing the dependence on noble-metal electrocatalysts and developing a cost-effective alkaline HER catalyst,while considering the principles of sustainable *** initial discussion covers the fundamental principle of HER,followed by an overview of prevalent techniques for synthesizing catalysts based on noble metals,along with a thorough examination of recent *** subsequent discussion focuses on the strategies employed to improve noble metalbased catalysts,including enhancing the intrinsic activity at active sites and increasing the quantity of active ***,this investigation concludes by examining the present state and future direction of research in the field of electrocatalysis for the HER.

关键词： Hydrogen evolution reaction Alkaline water electrolysis Electrocatalysts Noble metal-based Synthesis method Modification strategy

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Gradient age-precipitation behavior induced by gradient nano-grain in Mg-Gd-Ag-Zr alloy

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Journal of Iron and Steel Research International 2025年第1期32卷 19-24页

作者： Bang-jun li Jia-peng sun Jing Han Guo-song Wu College of Materials Science and Engineering Hohai UniversityNanjing 210024JiangsuChina School of Mechanical and Electrical Engineering China University of Mining and TechnologyXuzhou 221116JiangsuChina

Gradient nano-grained structure is frequently engineered into metallic materials,including Mg alloys,to achieve superior combination of strength and ***,the influence of this microstructural feature on aging precipitation behavior remains inadequately *** this study,the age-precipitation behavior of a gradient nano-grained Mg-Gd-Ag-Zr alloy prepared via ultrasonic severe surface rolling was *** result indicates that the aging precipitation behavior exhibits a depth-dependent variation within this *** the nano-grained surface layer,hierarchicalβnano-precipitates are predominant,while at greater depths,the precipitates consist ofβnanoparticles located at grain boundaries,along with intragranularβ′andγ″*** formation ofβnano-precipitates deviates from the conventional precipitation behavior observed in Mg-Gd-Ag alloys,and is attributed to the high density of defects induced by the surface nano-grained *** finding advances our understanding of the precipitation behavior in the alloys with heterogeneous microstructure.

关键词： Mg alloy Gradient Precipitation Aging behavior Microstructure

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The Teleconnection between Rainfall over the Northeastern Slope of the Tibetan Plateau and Downstream Regions:Insights from 20 Years of Heavy Rainfall Events

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Advances in Atmospheric Sciences 2025年第2期42卷 327-341页

作者： Wei sun Rucong YU Jian li Zewen li State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081China Institute of Tibetan Plateau Meteorology China Meteorological AdministrationChengdu 610072China Department of Atmospheric Science Yunnan UniversityKunming 650091China Inner Mongolia Autonomous Region Mete-orological Service Center Hohhot 010051China

The connection between rainfall over topographic regions and their downstream areas represents a phenomenon of great concern in atmospheric *** on the rainfall events of the past two decades,we analyzed the impact of rainfall over the Northeastern Slope of the Tibetan Plateau(NSTP)on rainfall in downstream *** discovered that rainfall followed two propagation routes,guided by two modes related to the three-dimensional circulation *** the first mode,dominated by cold(warm)anomalies along the west(east)direction,rainfall over the NSTP was concentrated between an upstream cyclonic and a downstream anti-cyclonic anomalous circulation(an upstream trough and a downstream ridge).This pattern was accompanied by upper-level divergence,low-level convergence,a deep moist layer,and a vertical *** a consequence of the eastward movement of the trough-ridge system associated with the coldwarm anomalies,the rainfall over the NSTP moved eastward along 37°-40°N,reaching North China after about 36 *** the second mode,the circulation structure was also dominated by cold-warm anomalies but rotated clockwise,introducing cold anomalies to the northeast and warm anomalies to the east of the *** the southeastward movement of the circulation structure,rainfall concentrated upstream of the anti-cyclonic circulation around the warm center before moving southeastward to the Sichuan Basin along the eastern edge of the plateau after 30-36 *** findings of this study could broaden the understanding of rainfall-related teleconnection between two distant regions and offer helpful guidance for identifying early signals of rainfall disasters over the Chinese mainland.

关键词： teleconnection rainfall propagation three-dimensional circulation structure upper-tropospheric temperature anomaly

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Characterizing large deformation of soft rock tunnel using microseismic monitoring and numerical simulation

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Journal of Rock Mechanics and Geotechnical Engineering 2025年第1期17卷 309-322页

作者： Yuepeng sun Nuwen Xu Peiwei Xiao Zhiqiang sun Huailiang li Jun liu Biao li State Key Laboratory of Hydraulics and Mountain River Engineering College of Water Resource and HydropowerSichuan UniversityChengdu610065China Power China Sinohydro Bureau 7 Co. Ltd.Chengdu610213China Key Laboratory of Earth Exploration and Information Technology Chengdu University of TechnologyChengdu610059China School of Geoscience and Technology Southwest Petroleum UniversityChengdu610500China

Surrounding rock deterioration and large deformation have always been a significant difficulty in designing and constructing tunnels in soft *** key lies in real-time perception and quantitative assessment of the damaged area around the *** in situ microseismic(MS)monitoring system is established in the plateau soft tock *** technique facilitates spatiotemporal monitoring of the rock mass's fracturing expansion and squeezing deformation,which agree well with field convergence deformation *** formation mechanisms of progressive failure evolution of soft rock tunnels were discussed and analyzed with MS data and numerical *** results demonstrate that:(1)Localized stress concentration and layered rock result in significant asymmetry in micro-fractures propagation in the tunnel radial *** excavation continues,the fracture extension area extends into the deep surrounding rockmass on the east side affected by the weak bedding;(2)Tunnel excavation and long-term deformation can induce tensile shear action on the rock mass,vertical tension fractures(account for 45%)exist in deep rockmass,which play a crucial role in controlling the macroscopic failure of surrounding rock;and(3)Based on the radiated MS energy,a three-dimensional model was created to visualize the damage zone of the tunnel surrounding *** model depicted varying degrees of damage,and three high damage zones were ***,the depth of high damage zone ranged from 4 m to 12 *** study may be a valuable reference for the warning and controlling of large deformations in similar projects.

关键词： Soft rock tunnel MS monitoring Progressive failure characteristic Excavation damage zone Failure mechanism

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MOF-derived Ni3Fe/Ni/NiFe2O4@C for enhanced hydrogen storage performance of MgH2

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Journal of Energy Chemistry 2025年第2期101卷 333-344页

作者： Yangping Chen Bolin sun Guoqing Zhang Siyuan Ni Canbing li Juxiong Tian Yanrui Zhang Xinxi li School of Materials and Energy Guangdong University of Technology Shen Zhen Source Sensor Technology CO. Ltd Department of Electrical Engineering Shanghai Jiao Tong University China Power Investment Xinjiang Energy & Chemical Group Hotan Co.Ltd

Magnesium hydride（MgH2） is an important material for hydrogen（H2） storage and transportation owing to its high capacity and ***,its intrinsic properties have considerably limited its industrial *** this study,the NiFe-800 catalyst as metal-organic framework（MOF） derivative was first utilized to promote the intrinsic properties of *** to pure MgH2,which releases1.24 wt% H2in 60 min at 275℃,the MgH2-10 NiFe-800 composite releases 5.85 wt% H2in the same *** at a lower temperature of 250℃,the MgH2-10 NiFe-800 composite releases 3.57 wt% H2,surpassing the performance of pure MgH2at 275℃.Correspondingly,while pure MgH2absorbs 2.08 wt% H2in60 min at 125℃,the MgH2-10 NiFe-800 composite absorbs 5.35 wt% H2in just 1 min,Remarkably,the MgH2-10 NiFe-800 composite absorbs 2.27 wt% H2in 60 min at 50℃ and 4.64 wt% H2at 75℃.This indicates that MgH2-10 NiFe-800 exhibits optimum performance with excellent kinetics at low ***,the capacity of the MgH2-10 NiFe-800 composite remains largely stable after ***,the Mg2Ni/Mg2NiH4acts as a "hydrogen pump",providing effective diffusion channels that enhance the kinetic process of the composite during ***,Fe0facilitates electron transfer and creates hydrogen diffusion channels and catalytic ***,carbon（C） effectively prevents particle agglomeration and maintains the cyclic stability of the ***,the synergistic effects of Mg2Ni/Mg2NiH4,Fe0,and C considerably improve the kinetic properties and cycling stability of *** work offers an effective and valuable approach to improving the hydrogen storage efficiency in the commercial application of MgH2.

关键词： Catalysts Hydrogen energy MgH2 MOF derivative Solid state storage

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Associations between food insecurity with gestational diabetes mellitus and maternal outcomes mediated by dietary diversity:A cross-sectional study

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World Journal of Diabetes 2025年第2期16卷 92-102页

作者： Hong-li Hou Gui-Xia sun Department of Gynecology and Obstetrics Children’s Hospital of ShanxiWomen Health Center of ShanxiTaiyuan 030001Shanxi ProvinceChina

BACKGROUND Food insecurity(FI)during pregnancy negatively impacts maternal health and raises the risk of gestational diabetes mellitus(GDM)and pregnancy-induced hypertension(PIH),resulting in adverse outcomes for both mother and *** To investigate the relationships between FI and pregnancy outcomes,particularly GDM and PIH,while also examining the mediating role of the dietary diversity score(DDS).METHODS A cross-sectional study was undertaken to examine this relationship,involving 600 pregnant *** were women aged 18 years or older who provided complete data on FI and pregnancy *** FI was measured via the Household Food Security Survey Module,with GDM defined as fasting plasma glucose levels of≥5.1 mmol/L or a 2-hour oral glucose tolerance test value of≥8.5 mmol/*** DDS is determined by evaluating one's food consumption based on nine distinct food groups.A logistic regression model was used to explore the relationship between FI and PIH,and *** Seventeen percent of participants reported experiencing FI during *** study found a significant association between FI and an elevated risk of GDM[odds ratio(OR)=3.32,95%CI:1.2-5.4].Once more,food-insecure pregnant women had higher rates of PIH(OR=0.10,95%CI:0.02-0.45)and they also faced a higher likelihood of neonatal complications,such as neonatal intensive care unit’s admissions and the birth of infants with extremely low birth *** FI wasfurther linked to metabolic disruptions,such as elevated fasting blood sugar(FBS),low-density lipoprotein cholesterol,and triglyceride *** results indicate that the DDS acts as a significant mediator in the relationship between FI and the incidence of *** particular,the mediation analysis showed that approximately 65%of the effect was mediated through DDS(P=0.002).CONCLUSION These findings underscore the serious challenges that FI presents during pregnancy and its effects on maternal and infant ***,the study

关键词： Food insecurity Gestational diabetes mellitus Gestational hypertension Pregnancy Maternal health Infant health Dietary diversity score

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Malicious Document Detection Based on GGE Visualization

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Computers, Materials & Continua 2025年第1期82卷 1233-1254页

作者： Youhe Wang Yi sun Yujie li Chuanqi Zhou Henan Province Key Laboratory of Information Security Information Engineering UniversityZhengzhou450000China

With the development of anti-virus technology,malicious documents have gradually become the main pathway of Advanced Persistent Threat(APT)attacks,therefore,the development of effective malicious document classifiers has become particularly ***,detection methods based on document structure and behavioral features encounter challenges in feature engineering,these methods not only have limited accuracy,but also consume large resources,and usually can only detect documents in specific formats,which lacks versatility and *** address such problems,this paper proposes a novel malicious document detection method-visualizing documents as GGE images(Grayscale,Grayscale matrix,Entropy).The GGE method visualizes the original byte sequence of the malicious document as a grayscale image,the information entropy sequence of the document as an entropy image,and at the same time,the grayscale level co-occurrence matrix and the texture and spatial information stored in it are converted into grayscale matrix image,and fuses the three types of images to get the GGE color *** Convolutional Block Attention Module-EfficientNet-B0(CBAM-EfficientNet-B0)model is then used for classification,combining transfer learning and applying the pre-trained model on the ImageNet dataset to the feature extraction process of GGE *** shown in the experimental results,the GGE method has superior performance compared with other methods,which is suitable for detecting malicious documents in different formats,and achieves an accuracy of 99.44%and 97.39%on Portable Document Format(PDF)and office datasets,respectively,and consumes less time during the detection process,which can be effectively applied to the task of detecting malicious documents in real-time.

关键词： Malicious document visualization EfficientNet-B0 convolutional block attention module GGE image

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Multiple-stage W mineralization in the Guanfang W deposit,southeastern Yunnan Province,China:Insights from scheelite in-situ trace elemental and Sr isotopic analyses

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Acta Geochimica 2025年第1期44卷 112-127页

作者： Bin sun Yi liu Zhigang Kong Xuelong liu Xiaojun Jiang Chao li Wenchang li Faculty of Land Resources Engineering Kunming University of Science and TechnologyNo.727 South Jingming RoadChenggong DistrictKunming City 650093Yunnan ProvinceChina Institute of Mineral Resources Chinese Academy of Geological SciencesNo.26 Baiwanzhuang StreetXicheng DistrictBeijing 100037China

The Guanfang large-scale W deposit is located in the W polymetallic ore concentration area of Bozhushan in southeastern Yunnan,*** extensive research,the fluid evolution process of the deposit remains ambiguous,leading to controversy regarding its *** study conducted a detailed field geological survey,with systematic sampling of the KT6 orebody,to delineate mineralization *** mineralogy work,including the use of CL images of scheelite,in-situ LA-ICP-MS trace elements,and Sr isotopes,was carried out on diff erent generations of scheelite formed in various *** findings identified the evolution of fluids in the mineralization process,shedding light on the genesis of the *** study revealed four mineralization stages at the Guanfang W deposit:prograde skarn stage,retrograde skarn stage,quartz-sulfide stage,and carbonate-fluorite *** erent generations of scheelite(Sch I,Sch II,Sch III)were observed in the first three stages,displaying distinct chondrite-normalized REE *** REE of Sch I mainly substituted into the Ca site by REE^(3+)+□_(Ca),and there may be a similar substitution of Nb for REE,whereas it is not the main substitution *** REE of Sch II mainly enter the scheelite lattice in the form of REE 3++na+,and there may be a substitution of Nb for REE *** the early stage,The REE of Sch III was mainly replaced by Nb for REE isomorphism,while in the later stage,the replacement mode of REE^(3+)+□_(Ca)coexisted with *** Mo content in scheelite,along with the corresponding Eu anomalies in both scheelite and garnet,collectively imply that the ore-forming fluids during various mineralization stages were predominantly oxidizing,with only slight reducibility observed in Sch *** in-situ Sr isotope ratios of scheelite concentrates ranged from 0.7093 to 0.7153,resembling those of the Bozhushan granite,indicating a relationship between W mineralization and *** addition,the Y/Ho ratios of scheeli

关键词： Guanfang W deposit Trace elements of scheelite In-situ Sr isotopes Southeast Yunnan

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