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Statistical Research on Megahertz-peaked Spectra Pulsars

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Research in Astronomy and Astrophysics 2025年第1期25卷 116-134页

作者： hong-Bing Cai li Chen Shi-Dang li Kai wang Hang liu JSNU SPBPU Institute of Engineering & SINO RUSSIAN Institute Jiangsu Normal University School of Physics and Electronic Engineering Jiangsu Normal University

Megahertz-peaked spectra(MPS) pulsars are referred as cases whose radio spectra turn over around 100 MHz. We identified 53 MPS pulsars based on the spectral data from the literature, and statistically analyzed the spatial location distribution, the magnetic field-period distribution, peak frequencies, spectral indices, and dispersion measures of these MPS pulsars. We found that there is a strong positive correlation between the dispersion measures and the peak frequencies of MPS pulsars, and negative correlations of the dispersion measures with spectral indices and the ages are also found. Such correlations suggest that the interstellar medium is an important factor that affects observational properties of MPS pulsars.

关键词： (stars:) pulsars: general ISM: general radio continuum: general

The role of sulfur cycle in new particle formation:Cycloaddition reaction of SO_(3)to H_(2)S

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Journal of Environmental Sciences 2025年第2期148卷 489-501页

作者： Haijie Zhang Wei wang liang Fan Junling li Yanqin Ren hong li Rui Gao Yisheng Xu State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing 100012China Key Laboratory of Cluster Science Ministry of Education of ChinaSchool of Chemistry and Chemical EngineeringBeijing Institute of TechnologyBeijing 100081China

The chemistry of sulfur cycle contributes significantly to the atmospheric nucleation process,which is the first step of new particle formation(NPF).In the present study,cycloaddition reaction mechanism of sulfur trioxide(SO_(3))to hydrogen sulfide(H_(2)S)which is a typical air pollutant and toxic gas detrimental to the environment were comprehensively investigate through theoretical calculations and Atmospheric Cluster Dynamic Code ***-phase stability and nucleation potential of the product thiosulfuric acid(H_(2)S_(2)O_(3),TSA)were further analyzed to evaluate its atmospheric *** any catalysts,the H_(2)S+SO_(3)reaction is infeasible with a barrier of 24.2 kcal/*** nucleation precursors formic acid(FA),sulfuric acid(SA),and water(H_(2)O)could effectively lower the reaction barriers as catalysts,even to a barrierless reaction with the efficiency of cis-SA>trans-FA>trans-SA>H_(2)***,the gas-phase stability of TSA was investigated.A hydrolysis reaction barrier of up to 61.4 kcal/mol alone with an endothermic isomerization reaction barrier of 5.1 kcal/mol under the catalytic effect of SA demonstrates the sufficient stability of ***,topological and kinetic analysis were conducted to determine the nucleation potential of *** clusters formed by TSA and atmospheric nucleation precursors(SA,ammonia NH_(3),and dimethylamine DMA)were thermodynamically ***,the gradually decreasing evaporation coefficients for TSA-base clusters,particularly for TSA-DMA,suggests that TSA may participate in NPF where the concentration of base molecules are relatively *** present new reaction mechanismmay contributes to a better understanding of atmospheric sulfur cycle and NPF.

关键词： New particle formation(NPF) Atmospheric sulfur cycle Nucleation process Reaction mechanism Hydrogen sulfide(H_(2)S) Atmospheric Cluster Dynamic Code (ACDC)

Pyrrolic nitrogen coordinated Ni^(2+) dual-atom catalyst for boosting CO_(2) electroreduction

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Science China Chemistry 2025年第2期68卷 570-579页

作者： Zhi-Wei Chen hong-Juan wang Chang liu Xiu-li Lu Tong-Bu Lu MOE International Joint Laboratory of Materials Microstructure Institute for New Energy Materials and Low Carbon TechnologiesSchool of Materials Science and EngineeringTianjin University of TechnologyTianjin 300384China

Nitrogen-doped carbon materials have been widely used for the constructions of single-atom catalysts,while the effect of different species of doped nitrogen on the catalytic activity of CO_(2) electroreduction has rarely been *** we found that pyrrolic-N coordinated Ni2+catalysts display much higher electrocatalytic CO_(2)-to-CO activity and selectivity than the corresponding pyridinic-N coordinated low valent Ni^((0–+2))catalysts,and pyrrolic-N coordinated Ni2 dual-atoms catalyst of Ni2/N-CNTs exhibits the best electrocatalytic performance,with over 90%Faradaic efficiencies in a broad potentials from−0.6 to−1.2 V *** hydrogen electrode,as well as an outstanding CO specific current of 56.2 A/mgNi and high turnover frequency of 6.2×10^(4) h^(−1),over 7-times higher than those of pyridinic-N coordinated Ni *** results indicate the weak electron-donor nature of pyrrolic-N facilitates the generation of a reduced active site at low overpotential for boosting CO_(2) *** functional theory calculations reveal that the reaction free energy for the*COOH formation on pyrrolic-N coordinated Ni catalysts are lower than those on pyridinic-N coordinated Ni catalysts,and a H_(2)Oadsorbed Ni_(2)/N-CNTs displays the optimized reaction free energy for both*COOH formation and CO desorption,which derive the best catalytic performance.

关键词： dual-atom catalyst CO_(2) electroreduction synergistic catalysis pyrrolic-N pyridinic-N

Iron scrap derived nano zero-valent iron/biochar activated persulfate for p-arsanilic acid decontamination with coexisting microplastics

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Journal of Environmental Sciences 2025年第5期151卷 733-746页

作者： Zihan Shu Hailan Yang Shujing Ye hong li Zhiming Yang Chuang li Xiaofei Tan Shaobo liu Hou wang College of Environmental Science and Engineering Hunan University and Key Laboratory of Environmental Biology and Pollution Control(Hunan University)Ministry of EducationChangsha 410082China Shenzhen Research Institute of Hunan University Shenzhen 518055China School of Resources Environment and MaterialsGuangxi UniversityNanning 530004China College of Resources and Environment University of Chinese Academy of SciencesBeijing 101408China School of Architecture and Art Central South UniversityChangsha 410083China School of Metallurgy and Environment Central South UniversityChangsha 410083China

P-arsanilic acid(AA)has received widespread attention because of its conversion to more toxic inorganic arsenic compounds(arsenate and arsenite)in the natural *** removal process and mechanisms with co-existence of microplastics remain *** this study,biochar loaded with nano zero-valent iron(nZVI)particles(ISBC)was prepared by using iron scrap obtained from a steel works and wood chips collected from a wood processing *** advanced oxidation system of sodium persulfate(PDS)activated by ISBC was applied for AA degradation and inorganic arsenic control in aqueous *** than 99%of the AA was completely degraded by the ISBC/PDS system,and the As(III)on AA was almost completely oxidized to As(V)and finally removed by ***_(3)−inhibited the removal of AA by the ISBC/PDS system,while Cl^(−)had a dual effect that showing inhibition at low concentrations yet promotion at high *** effect of microplastics on the degradation of AA by the ISBC/PDS system was further investigated due to the potential for combined microplastic and organic arsenic contamination in rural/remote *** were found to have little effect on AA degradation in the ISBC/PDS system,while affect the transport of inorganic arsenic generated from AA ***,this study provides new insights and methods for efficient removal of p-arsanilic acid from water with coexisting microplastics.

关键词： P-arsanilic acid Biochar Arsenate and arsenite Microplastics

Mechanism analysis of effect of MgO on reduction swelling behaviour of iron pellets in CO/H_(2)atmosphere based on first-principles calculations

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Journal of Iron and Steel Research International 2025年第1期32卷 73-84页

作者： hong-ming Long Jing-shu An Xing-wang li Ting Wu Sheng-ping He Jie Lei School of Metallurgical Engineering Anhui University of TechnologyMa’anshan243032AnhuiChina Key Laboratory of Metallurgical Emission Reduction and Resource Comprehensive Utilization(Anhui University of Technology) Ministry of EducationMa’anshan243002AnhuiChina College of Materials Science and Engineering Chongqing UniversityChongqing400044China

To explain the influence mechanism of MgO on the consolidation and reduction characteristics of roasted iron pellets,the properties and structure of pellets were investigated from *** indicated that the MgO addition decreased the reduction swelling index(RSI)and reduction degree of pellets in both CO and H_(2)*** the stepwise reduction process of Fe2O3→Fe3O4→FeO,the reduction behaviour of pellets in CO and H_(2)was similar,while the reduction rate of pellets in H_(2)atmosphere was almost twice as high as that in CO *** the stepwise reduction process of FeO→Fe,the RSI of pellets showed a logarithmic increase in CO atmosphere and a linear decrease in H_(2)*** investigated by first-principles calculations,C and Fe mainly formed chemical bonds,and the CO reduction process released energy,promoting the formation of iron ***,H and Fe produced weak physical adsorption,and the H_(2)reduction process was endothermic,inhibiting the generation of iron *** Mg2+doping in FexO,the nucleation region of iron whiskers expanded in CO reduction process,and the morphology of iron whiskers transformed from“slender”to“stocky,”reducing RSI of the pellets.

关键词： MgO CO atmosphere H_(2)atmosphere Reduction degree Reduction swelling index First-principles calculation

Thickness and sp3 bond modulation of（Ti/tetrahedral amorphous carbon）_n multilayer coatings

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Tungsten 2025年第1期7卷 152-160页

作者： Zhi-Jun Xie Jia-lin li ling Gong Xiang-li Zhong hong-Jia Song Jin-Bin wang National-Provincial Laboratory of Special Function Thin Film Materials School of Materials Science and Engineering Xiangtan University

The durability of wear-resistant tetrahedral amorphous carbon（ta-C） coatings is intimately linked to their thickness and the concentration of *** enhance the lifespan of the coatings,we have prepared a multilayer coating consisting of alternating layers of Ti and ta-C,denoted as（Ti/ta-C）_n,using arc ion plating.A multi-layer structure in conjunction with stage cooling is employed to enhance the thickness and promote *** results indicate that the ID/IGvalue,representing the ratio of the intensity of the D peak to that of the G peak in Raman spectroscopy,decreases from 0.85 when no stage cooling is applied to 0.35 when stage cooling is employed,suggesting an enhancement in the fraction of sp3bonds within the *** obtained（Ti/ta-C）_n multilayer coating without peeling off has a maximum thickness of 1.14 μm,which is almost double that of the ta-C coating single layer *** the same time,the coating has a low coefficient of friction,down to 0.069,and maintains excellent friction properties with a wear rate of 3.4×10-6mm3·N-1·*** results conclusively show that the preparation technology can enhance both thickness and sp3bonding in ta-C coatings,significantly expanding their utility across tools,molds,and precision engineering components.

关键词： Arc ion plating Multilayer structure sp3 bond Ta-C coating Wear resistance

Health risks of rare earth elements exposure:Impact on mitochondrial DNA copy number and micronucleus frequency

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Journal of Environmental Sciences 2025年第5期151卷 150-160页

作者： Shiyi hong Yali Zhang Qiaojian Zhang Zekang Su Guiping Hu li wang Shanfa Yu Xiaojun Zhu Guang Jia Department of Occupational and Environmental Health Sciences School of Public HealthPeking UniversityBeijing 100083China School of Engineering Medicine and Beijing Advanced Innovation Center for Big Data-Based Precision Medicine Beihang UniversityBeijing 100083China Department of Toxicology School of Public HealthBaotou Medical CollegeBaotouInner Mongolia 014040China Henan Institute for Occupational Medicine Zhengzhou 450052China National Center for Occupational Safety and Health Beijing 102308China Beijing Key Laboratory of Toxicological Research and Risk Assessment for Food Safety School of Public HealthPeking UniversityBeijing 100083China

Toxic effects in terms of mitochondria and hereditary substances have been characterized in vitro for individual rare earth elements,while,the joint effects of mixed elements exposure in the population remain *** on the Occupational Chromate Exposure Dynamic Cohort of China,this study investigated the relationship between 15 blood rare earth elements(cerium,dysprosium,erbium,europium,gadolinium,holmium,lanthanum,lutetium,neodymium,praseodymium,samarium,terbium,thulium,yttrium,and ytterbium)and mitochondrial DNA copy number(MtDNACN)as well as peripheral blood lymphocyte micronucleus frequency(MNF).The elastic net was used to select elements highly correlated with effect indicators,whose dose-response relationships were further illustrated by restricted cubic *** kernel regressionwas employed to explore the combined effects of elements and the contributions of single *** results showed that most rare earth elementswere positively correlatedwith effect indicators,with yttrium showing the strongest association(β(95%CI):0.139(0.1089–0.189)for MtDNACN,0.937(0.345–1.684)for MNF).In the mixed exposure model,with the exposure level fixed at the 50th percentile as the reference,the effect estimates on MtDNACN and MNF increased by 0.228 and 0.598 units,respectively,at the 75th *** single effect analysis implied that yttrium,lanthanum and terbium contributed the most to the elevation of MtDNACN,while yttrium posed the highest risk for genetic damage,accordingly,we provided recommendations to prioritize these elements of *** addition,we observed a chief mediating effect of MtDNACN on the elevation of MNF caused by lanthanum,whereas further mechanistic exploration is required to confirm this finding.

关键词： Rare earth elements Mitochondrial DNA copy number Micronucleus frequency Mixed effect

Effects of mode of reproduction on genetic polymorphism and divergence in wild yams(Dioscoreaceae:Dioscorea)

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Plant Diversity 2025年第1期47卷 136-147页

作者： Xin wang Qing-hong Feng Zhi-Hua Zeng Zhi-Qiang Zhang Jie Cai Gao Chen De-Zhu li hong wang Wei Zhou Germplasm Bank of Wild Species&Yunnan Key Laboratory of Crop Wild Relatives Omics Kunming Institute of BotanyChinese Academy of SciencesKunmingYunnan 650201China University of Chinese Academy of Sciences Beijing 100049China Yunnan Key Laboratory of Plant Reproductive Adaptation and Evolutionary Ecology Institute of BiodiversitySchool of Ecology and Environmental ScienceYunnan UniversityKunmingYunnan 650504China Research Institute of Tropical Forestry Yunnan Academy of Forestry and GrasslandXishuangbannaYunnan 666102China CAS Key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of BotanyChinese Academy of SciencesKunmingYunnan 650201China Key Laboratory of Phytochemistry and Natural Medicines Kunming Institute of BotanyChinese Academy of SciencesKunmingYunnan 650201China lijiang Forest Biodiversity National Observation and Research Station Kunming Institute of BotanyChinese Academy of SciencesLijiangYunnan 674100China

Evolutionary transitions from sexual to asexual reproduction should have significant influences on genetic divergence and polymorphism at the genome *** lineages with diverse reproductive systems provide opportunities to investigate this question using comparative approaches and studies of molecular *** investigated evidence for differences among the transcriptomes of 19 Dioscorea species(wild yams)with diverse reproductive *** included sexual species,those that propagate primarily by bulbils,and those with mixed sexual and asexual reproductive *** examined how transitions between these reproductive systems affected between-species divergence and within-species *** asexual species exhibited a reduced efficacy of natural selection and accumulation of deleterious mutations for both divergence and *** contrast,species with mixed reproductive strategies involving both seed and clonal reproduction showed no evidence of an increased fixation of harmful mutations at the divergence level,while an accumulation of genetic load present in polymorphism was *** study indicates that the genetic consequences of evolutionary transitions from sexual to predominantly clonal reproduction is likely to depend on both the duration and extent of asexuality occurring in populations.

关键词： Asexual Deleterious mutations Dioscorea Molecular evolution Selection

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Study on the diagnostic criteria of syndrome of dampness obstruction in idiopathic membranous nephropathy based on expert consensus

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Journal of Traditional Chinese Medicine 2025年第1期45卷 167-175页

作者： wang Dan HUANG Xiaoyan li Ping hong Xiaofan ZHANG Yumin wang Rongrong BAO Kun liANG Xing Nephrology Department Qianxinan Autonomous Prefecture Hospital of Traditional Chinese Medicine Nephrology Department Guangdong Provincial Hospital of Chinese Medicine Guangdong Provincial Key Laboratory of Chinese Medicine for Prevention and Treatment of Refractory Chronic Disease the Second Affiliated Hospital of Guangzhou University of Chinese Medicine State Key Laboratory of Dampness Syndrome of Chinese Medicine the Second Affiliated Hospital of Guangzhou University of Chinese Medicine State Key Laboratory of Dampness Syndrome of Chinese Medicine The Second Affiliated Hospital of Guangzhou University of Chinese Medicine Guangdong-hong Kong-Macau Joint Lab on Chinese Medicine and Immune Disease Research

OBJECTIVE: To reach consensus on the diagnostic criteria of syndrome of dampness obstruction in idiopathic membranous nephropathy(IMN) patients by literature research and expert investigation(interviews and a Delphi method). METHODS: Our study was consistent with T/CACM 1336-2020. We searched the monographs and references published in the past 40 years(1983-2022), and established the diagnostic criteria pool of waterdampness syndrome and dampness-turbidity syndrome in Traditional Chinese Medicine(TCM) based on literature by using frequency statistics and correlation analysis. Expert investigation(interview method and two rounds of Delphi method) was used to form the diagnostic criteria of water-dampness syndrome and dampnessturbidity syndrome of idiopathic membranous nephropathy. Clinical diagnostic test research was carried out, and compared with “Diagnostic Criteria for dampness syndrome”(T/CACM 1454-2023) to evaluate the authenticity, reliability and clinical application value of the standard. RESULTS: A total of 122 relevant guides, standards, monographs and documents were included through searching books and Chinese databases. Four experts were interviewed and two rounds of delphi method(75 experts nationwide) were carried out. The experts' opinions are relatively concentrated and the differences are small. Based on the weight of each index, the diagnostic criteria indexes of water-dampness syndrome and dampness-turbidity syndrome were selected. After discussion by the core group members, the diagnostic model of "necessary symptoms and optional symptoms" was established, and the final diagnostic criteria of waterdampness syndrome and dampness-turbidity syndrome were established. One hundred and ninety-one inpatients and outpatients of Guangdong Provincial Hospital of Chinese Medicine from January 2021 to February 2023 were included in Diagnostic test study. There was no statistical difference in gender, age and course of disease(P > 0.05). The sensitivity and s

关键词： combination of disease and syndrome diagnostic tests, routine glomerulonephritis, membranous syndrome diagnostic criteria syndrome of dampness obstruction