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Research in Astronomy and Astrophysics 2025年第2期 256-268页

作者： Hao Xiang Zhong-Kai zhang Lan Du ze-jun Liu Xu-Qiao Wang College of Geospatial Information Information Engineering University Henan Industrial Technology Academy of Spatio-Temporal Big Data College of Geography and Environmental Science Henan University

The Earth Orientation Parameters(EOP) provide a time-varying transition relationship between the International Terrestrial Reference Frame and the International Celestial Reference Frame. To support deep space exploration and the Beidou Navigation Satellite System, the Chinese New-generation Very Long Baseline Interferometry Network(CNVN) is under construction for independent monitoring of the EOP. This paper evaluates the performance of existing 4-antenna CNVN through a batch generated observation schedules followed by extensive Monte Carlo simulations. The optimal positions of the fifth and sixth antennas of CNVN are found from 24hypothetical antenna positions uniformly distributed in China. In this process, the weighted parameters are optimized, which not only reduce the possibility of large error of EOP estimation accuracy due to unreasonable combination, but also greatly reduce the calculation cost.

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Selenate oxyanion-intercalated NiFeOOH for stable water oxidation via lattice oxygen oxidation mechanism

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Journal of Energy Chemistry 2025年第2期101卷 676-684页

作者： Yijie zhang Weiyi zhang Xiaowen zhang Jinping Li Guang Liu Shanxi Key Laboratory of Gas Energy Efficient and Clean Utilization College of Chemical Engineering and Technology Taiyuan University of Technology Shanxi Research Institute of Huai Rou Laboratory

Transition metal-based compounds can serve as pre-catalysts to obtain genuine oxygen evolution reaction（OER） electrocatalysts in the form of oxyhydroxides through electrochemical ***,the role and existence form of leached oxygen anions are still ***,we selected iron selenite-wrapped hydrated nickel molybdate（denoted as NiMoO/FeSeO） as a pre-catalyst to study the oxyanion *** is surprising to find that SeO2-exists in the catalyst in the form of intercalation,which is different from previous studies that suggest that anions are doped with residual elements after electrochemical activation,or adsorbed on the catalyst *** experiment and theoretical calculations show that the existence of SeO42-intercalation effectively adjusts the electronic structure of NiFeOOH,promotes intramolecular electron transfer and O-O release,and thus lowers the reaction energy *** expected,the synthesized NiFeOOH-SeO only needs 202 and 285 mV to attain 100 and 1000 mA cm-2in 1 M ***,the anion exchange membrane water electrolyzer（AEMWE） consisting of NiFeOOHSeO anode and Pt/C cathode can reach 1 A cm-2at 1.70 V and no significant attenuation within 300 *** findings provide insights into the mechanism,by which the intercalated oxyanions enhance the OER performance of NiFeOOH,thereby facilitating large-scale hydrogen production through AEMWE.

关键词： Anion exchange membrane electrolyzer Industrial current densities Lattice oxygen oxidation Oxyanion intercalation Water splitting

Plasma metabolomics combined with mass spectrometry imaging reveals crosstalk between tumor and plasma in gastric cancer genesis and metastasis

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Chinese Chemical Letters 2025年第1期36卷 506-512页

作者： Yanhua Chen Xian Ding jun Zhou Zhaoying Wang Yunhai Bo Ying Hu Qingce Zang Jing Xu Ruiping zhang Jiuming He Fen Yang zeper Abliz Key Laboratory of Mass Spectrometry Imaging and Metabolomics(State Ethnic Affairs Commission) Center for Imaging and Systems BiologyCollege of Life and Environmental SciencesMinzu University of ChinaBeijing 100081China State Key Laboratory of Bioactive Substance and Function of Natural Medicines Institute of Materia MedicaChinese Academy of Medical SciencesPeking Union Medical CollegeBeijing 100050China Key Laboratory of Carcinogenesis and Translational Research(Ministry of Education/Beijing) Department of Gastrointestinal OncologyPeking University Cancer Hospital&InstituteBeijing 100142China Key Laboratory of Carcinogenesis and Translational Research(Ministry of Education) Center of Drug Clinical TrialPeking University Cancer Hospital and InstituteBeijing 100142China Beijing Engineering Research Center of Food Environment and Public Health Minzu University of ChinaBeijing 100081China Key laboratory of Ethnomedicine of Ministry of Education School of PharmacyMinzu University of ChinaBeijing 100081China Key Laboratory of Carcinogenesis and Translational Research(Ministry of Education) Department of BioBankPeking University Cancer Hospital and InstituteBeijing 100142China Pharmacy Department of Beijing Chao–Yang Hospital Capital Medical UniversityBeijing 100020China

Gastric Carcinoma(GC)is a highly fatal malignant tumor with a poor *** elevated mortality rates are primarily due to its proclivity for late-stage *** the metabolic interactions between tumor microenvironment and the systemic bloodstream could help to clearly understand the mechanisms and identify precise biomarkers of tumor growth,proliferation,and *** this study,an integrative approach that combines plasma metabolomics with mass spectrometry imaging of tumor tissue was developed to investigate the global metabolic landscape of GC tumorigenesis and *** results showed that the oxidized glutathione to glutathione ratio(GSSH/GSH)became increased in non-distal metastatic GC(M0),which means an accumulation of oxidative stress in tumor ***,it was found that the peroxidation of polyunsaturated fatty acids,such as 9,10-EpOMe,9-HOTrE,etc.,were accelerated in both plasma and tumor tissues of distal metastatic GC(M1).These changes were further confirmed the potential effect of CYP2E1 and GGT1 in metastatic potential of GC by mass spectrometry imaging(MSI)and immunohistochemistry(IHC).Collectively,our findings reveal the integrated multidimensional metabolomics approach is a clinical useful method to unravel the bloodtumor metabolic crosstalk,illuminate reprogrammed metabolic networks,and provide reliable circulating biomarkers.

关键词： Metabolomics Spatial-resolved metabolomics Gastric cancer Blood-tumor metabolic crosstalk Lipid peroxidation

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A machine learning method approach for designing novel high strength and plasticity metastable β titanium alloys

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Progress in Natural Science:Materials International 2025年第01期 156-165页

作者： Zhiduo Liu Haoyu zhang Shuai zhang jun Cheng Yixuan He Ge Zhou Jiawei Liu Suping Song Lijia Chen School of Materials Science and Engineering Shenyang University of Technology Shenyang Key Laboratory of Advanced Structural Materials and Applications Shenyang University of Technology Northwest Institute for Nonferrous Metal Research Shaanxi Key Laboratory of Biomedical Metal Materials State Key Laboratory of Solidification Processing Northwestern Polytechnical University Ansteel Group Automation Co. Ltd

In order to improve efficiency and reduce costs, four machine learning models were established for the design of metastable β titanium alloys, including the Adaboost model, the LightGBM model, the Voting model, and the Stacking model. The accuracy of these models was evaluated, and all models exhibited excellent accuracy for tensile strength, yield strength, and elongation. The values of R-squared coefficients（R2） all greater than *** them, the LightGBM model showed the highest accuracy, with relatively smallest values of mean absolute error（MAE） and root mean square error（RMSE） and relatively largest value of R2. To further verify the accuracy of the model, a metastable β titanium alloy Ti-5.5Cr-5Al-4Mo-3Nb-2Zr was designed by the LightGBM model. The predicted values of the alloy's tensile strength, yield strength, and elongation under three heat treatment processes were in high agreement with the experimental values. The alloy exhibited optimal strength-plasticity matching after undergoing a solution treatment at 850°C for 0.5 h, followed by aging at 650°C for 8 h, with a tensile strength of 1317 MPa, an elongation of 11.17 %, and a strength-plasticity product of 14.711 GPa·%.

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How sediment dredging alters phosphorus dynamics in a lowland rural river?

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Journal of Environmental Sciences 2025年第1期147卷 189-199页

作者： Qimou zhang Jiacong Huang Yulai Ji Jing zhang Shuai zhang junfeng Gao Key Laboratory of Watershed Geographic Sciences Nanjing Institute of Geography and LimnologyChinese Academy of SciencesNanjing 210008China University of Chinese Academy of Sciences Beijing 10094China

China’s lowland rural rivers are facing severe eutrophication problems due to excessive phosphorus(P)from anthropogenic ***,quantifying P dynamics in a lowland rural river is challenging due to its complex interaction with surrounding areas.A P dynamic model(River-P)was specifically designed for lowland rural rivers to address this *** modelwas coupled with the Environmental Fluid Dynamics Code(EFDC)and the Phosphorus Dynamic Model for lowland Polder systems(PDP)to characterize P dynamics under the impact of dredging in a lowland rural *** on a two-year(2020-2021)dataset from a representative lowland rural river in the Lake Taihu Basin,China,the coupled model was calibrated and achieved a model performance(R^(2)>0.59,RMSE<0.04 mg/L)for total P(TP)*** research in the study river revealed that(1)the time scale for the effectiveness of sediment dredging for P control was~300 days,with an increase in P retention capacity by 74.8 kg/year and a decrease in TP concentrations of 23%after dredging.(2)Dredging significantly reduced P release from sediment by 98%,while increased P resuspension and settling capacities by 16%and 46%,respectively.(3)The sediment-water interface(SWI)plays a critical role in P transfer within the river,as resuspension accounts for 16%of TP imports,and settling accounts for 47%of TP *** the large P retention capacity of lowland rural rivers,drainage ditches and ponds with macrophytes are promising approaches to enhance P retention *** study provides valuable insights for local environmental departments,allowing a comprehensive understanding of P dynamics in lowland rural *** enable the evaluation of the efficacy of sediment dredging in P control and the implementation of corresponding P control measures.

关键词： Lowland rural river Phosphorus Sediment dredging Model ensemble Retention capacity

Hollow cerium nanoparticles synthesized by one-step method for multienzyme activity to reduce colitis in mice

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World Journal of Gastroenterology 2025年第5期31卷 94-104页

作者： Lin Mi Kai zhang Jian-Xia Ma Jian-Feng Yao Yi-Li Tong Zhi-jun Bao Department of General Medicine Huadong HospitalFudan UniversityShanghai 200040China Department of Gastroenterology Huadong HospitalFudan UniversityShanghai 200040China

BACKGROUND Inflammatory bowel disease(IBD)is a common chronic intestinal inflammatory *** oxidative stress is a treatment target for *** oxide(CeO2)nanomaterials as nanozymes with antioxidant activity are potential drugs for the treatment of *** To synthesize hollow cerium(H-CeO2)nanoparticles by one-step method and to validate the therapeutic efficacy of H-CeO2 in *** H-CeO2 was synthesized by one-step method and examined its characterization and nanoenzymatic ***,we constructed dextran sulfate so-dium(DSS)-induced colitis in mice to observe the effects of H-CeO2 on colonic *** effects of H-CeO2 on colon inflammation and reactive oxygen species(ROS)levels in IBD mice were detected by hematoxylin and eosin staining and dichlorofluorescein diacetate staining,***,the biological sa-fety of H-CeO2 on mice was evaluated by hematoxylin and eosin staining,blood routine,and blood *** H-CeO2 nanoparticles prepared by the one-step method were uniform,monodi-sperse and hollow.H-CeO2 had a good ability to scavenge ROS,∙OH and∙OOH.H-CeO2 reduced DSS-induced decreases in body weight and colon length,colonic epithelial damage,inflammatory infiltration,and ROS accumulation.H-CeO2 administration reduced the disease activity index of DSS-induced animals from about 8 to 5.H-CeO2 had no significant effect on body weight,total platelet count,hemoglobin,white blood cell,and red blood cell counts in healthy *** significant damage to major organs was observed in healthy mice following H-CeO2 *** The one-step synthesis of H-CeO2 nanomaterials had good antioxidant activity,biosafety,and inhibited deve-lopment of DSS-induced IBD in mice by scavenging ROS.

关键词： Inflammatory bowel disease Nanozymes Hollow cerium nanoparticles One-step method Cerium oxide biosafety

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TiAl合金中的氧扩散及恒温氧化研究现状

宇航材料工艺 2017年第3期47卷 10-13,18页

作者：赵瑞峰吴泽恩吴珺张铁邦李金山西北工业大学凝固技术国家重点实验室西安710072

TiAl合金由于高比强度和优异的高温力学性能,是一种极具应用潜力的轻质高温结构材料,但存在脆性大、室温塑性差以及800℃以上抗氧化能力不足是其工程应用的最大障碍。本文对TiAl合金的恒温氧化行为、氧扩散以及氧化后力学性能变化规律... 详细信息

TiAl合金由于高比强度和优异的高温力学性能,是一种极具应用潜力的轻质高温结构材料,但存在脆性大、室温塑性差以及800℃以上抗氧化能力不足是其工程应用的最大障碍。本文对TiAl合金的恒温氧化行为、氧扩散以及氧化后力学性能变化规律进行了总结。基于服役环境条件下合金中的氧扩散规律及受控机制,对改善合金高温抗氧化性能的表面处理和合金化研究现状进行了归纳。分析了TiAl合金高温抗氧化行为研究及其控制技术在今后一段时期的发展趋势。

关键词： TiAl合金氧化氧扩散力学性能研究现状

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Analyzing carbon emissions and influencing factors in Chengdu-Chongqing urban agglomeration counties

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Journal of Environmental Sciences 2025年第5期151卷 640-651页

作者： zhang Heng Lu Wenfu Peng Lindan zhang Key Laboratory of the Evaluation and Monitoring of Southwest Land Resources(Ministry of Education) Sichuan Normal UniversityChengdu 610068China The Institute of Geography and Resources Science Sichuan Normal UniversityChengdu 610068China

Majority of carbon emissions originate from fossil energy consumption,thus necessitating calculation and monitoring of carbon emissions from energy *** this study,we utilized energy consumption data from Sichuan Province and Chongqing Municipality for the years 2000 to 2019 to estimate their statistical carbon *** then employed nighttime light data to downscale and infer the spatial distribution of carbon emissions at the county level within the Chengdu-Chongqing urban ***,we analyzed the spatial pattern of carbon emissions at the county level using the coefficient of variation and spatial autocorrelation,and we used the Geographically and Temporally Weighted Regression(GTWR)model to analyze the influencing factors of carbon emissions at this *** results of this study are as follows:(1)from 2000 to 2019,the overall carbon emissions in the Chengdu-Chongqing urban agglomeration showed an increasing trend followed by a decrease,with an average annual growth rate of 4.24%.However,in recent years,it has stabilized,and 2012 was the peak year for carbon emissions in the Chengdu-Chongqing urban agglomeration;(2)carbon emissions exhibited significant spatial clustering,with high-high clustering observed in the core urban areas of Chengdu and Chongqing and low-low clustering in the southern counties of the Chengdu-Chongqing urban agglomeration;(3)factors such as GDP,population(Pop),urbanization rate(Ur),and industrialization structure(Ic)all showed a significant influence on carbon emissions;(4)the spatial heterogeneity of each influencing factor was evident.

关键词： Carbon emissions Chengdu-Chongqing urban agglomeration Spatial autocorrelation Geographically and temporally weighted regression

Automatic and Rapid Throughflow-Based Optimal Design Method for Multi-Stage Axial-Flow Compressors

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Journal of Thermal Science 2025年第1期34卷 77-91页

作者： LEI Fan zhang Xiawen JU Yaping zhang Chuhua Department of Fluid Machinery and Engineering School of Energy and Power EngineeringXi'an Jiaotong UniversityXi'an 710049China State Key Laboratory for Strength and Vibration of Mechanical Structures Xi'an Jiaotong UniversityXi'an 710049China Production and Environmental Department China Huaneng Group.Co.Ltd.Beijing 100031China

Throughflow design has the advantages of less time consumption and large optimization space,and thus is the corner stone of advanced design system of multi-stage axial-flow *** majority of relevant studies were limited to the throughflow inverse designs,and quite few works have been till now devoted to the throughflow optimal *** this work,an automatic and rapid throughflow-based optimal design method is proposed for axial-flow compressors in which a throughflow inverse design solver is embedded in optimal genetic algorithm to improve the design efficiency of axial-flow *** types of design parameters in the throughflow inverse design of axial-flow compressors,i.e.,swirl and shroud curve,are simultaneously used to optimize both the blade shape and flow *** proposed method is validated by the redesign optimization of the benchmark axial-flow compressor NASA Stage 35,and the CFD predictions show that the throughflow-based optimization leads to 1.18% efficiency benefit at design *** proposed method is then utilized to the two-dimensional throughflow optimal design of a large-scale 6.5-stage axial-flow industrial *** optimal design results are confirmed by CFD predictions,indicating that the proposed method can effectively improve the design adiabatic efficiency of the compressors by 1.09% within a few minutes on desk-top *** throughflow design implications are also obtained for advanced axial-flow industrial *** work could enhance the capability of throughflow design method and has engineering application value to explore the throughflow optimization space of multi-stage axial-flow compressors.

关键词： multi-stage axial-flow compressor throughflow design empirical correlations genetic algorithm aerodynamic optimization

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Experimental study on failure precursory characteristics and moisture content effect of pre-cracked rocks under graded cyclic loading and unloading

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International Journal of Mining Science and Technology 2025年第2期35卷 249-264页

作者： Wei zhang Dongxiao zhang Weiyao Guo Baoliang zhang School of Architecture and Engineering Liaocheng UniversityLiaocheng 252000China College of Energy and Mining Engineering Shandong University of Science and TechnologyQingdao 266590China

It is important to analyze the damage evolution process of surrounding rock under different water content for the stability of engineering rock *** on digital speckle correlation(DSCM),acoustic emission(AE)and electromagnetic radiation(EMR),uniaxial hierarchical cyclic loading and unloading tests were carried out on sandstones with different fracture numbers under dry,natural and saturated water content,to explore the fracture propagation,failure precursor characteristics and damage response mechanism under the influence of water content *** results show that with the increase of water content,the peak stress and crack initiation stress decrease gradually,and the decreases are 15.28%-21.11%and 17.64%-23.04%,*** peak strain and crack initiation strain increase gradually,and the increases are 19.85%-44.53%and 19.15%-41.94%,*** precracked rock with different water content is mainly characterized by tensile failure at different loading ***,with the increase of water content,the proportion of shear cracks gradually increases,while acoustic emission events gradually decrease,the dissipative energy and energy storage limits of the rock under peak load gradually decrease,and the charge signal increases significantly,which is because the lubrication effect of water reduces the friction coefficient between crack surfaces.

关键词： Damage mechanisms Pre-cracked rocks Crack propagation Water-rock interaction Graded cyclic loading and unloading