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Mechanical Behavior and Failure Mechanism of an As-Extruded Mg-11wt%Y Alloy at Elevated Temperature

Acta Metallurgica Sinica(English Letters) 2024年第6期37卷 969-981页

作者： lan Zhang Dao-Kui Xu Bao-Jie Wang cui-lan Lu Shuo Wang Xiang-Bo Xu Dong-Liang Wang Xin Lv En-Hou Han School of Materials Science and Engineering University of Science and Technology of ChinaShenyang110016China Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang110016China School of Environmental and Chemical Engineering Shenyang Ligong UniversityShenyang110159China Key Lab of Electromagnetic Processing of Materials Ministry of EducationNortheastern UniversityShenyang110819China Institute of Corrosion Science and Technology Guangdong510070China

Through carrying out the high-temperature tensile experiments on an as-extruded Mg-11wt%Y alloy at 350℃,400℃,450℃,500℃and 550℃,the mechanical behavior and fracture mechanisms at elevated temperatures are investigated and *** results show that with the increase of temperature,the yield strength and ultimate tensile strength of the alloy increase at first and then decrease,while that the elongation ratio decreases firstly and then *** the sample being tested at 350℃,the values of yield strength,ultimate tensile strength and the elongation ratio are 188 MPa,266 MPa and 11%,*** 400℃,the yield strength and ultimate tensile strength reach the maximum values of,respectively,198 MPa and 277 MPa,but the elongation ratio is the lowest and its value is only 8%.When the applied temperature is increased to 550℃,the values of yield strength and ultimate tensile strength,respectively,decrease to 140 MPa and 192 MPa and the elongation ratio increases to 38%.Failure analysis demonstrates that the fracture surfaces of different samples are mainly composed of plastic dimples and exhibit the typical characteristic of ductile *** observation to the fracture side surfaces indicates that at the temperatures of 350℃and 400℃,microcracks mainly initiate in the interior of Mg_(24)Y_(5)*** the temperatures are 450℃,500℃and 550℃,the cracks preferentially initiate at the Mg_(24)Y_(5)/α-Mg interfaces.

关键词： Mg-Y alloy High-temperature tensile properties Fracture mechanism Failure analysis

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Analysis of the Flow Field and Impact Force in High-Pressure Water Descaling

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Fluid Dynamics & Materials Processing 2024年第1期20卷 165-177页

作者： Yue cui Liyuan Wang jian Wu Haisheng Liu Di Wu Key Lab of Intelligent Equipment Digital Design and Process Simulation Hebei ProvinceTangshan UniversityTangshan063000China Department of Intelligent Manufacturing Tangshan Vocational College of Science and TechnologyTangshan063001China

This study aims to improve the performances of the high-pressure water descaling technology used in steel hot rolling *** particular,a 2050 mm hot rolling line is considered,and the problem is investigated by means of a fluid–structure interaction(FSI)method by which the descaling effect produced by rolling coils with different section sizes is *** a flat fan-shaped nozzle at the entrance of the R1R2 roughing mill,the outflow field characteristics and the velocity distribution curve on the strike line(at a target distance of 30–120 mm)are *** is found that the velocity in the center region of the water jet with different target distances is higher than that in the boundary *** the target distance increases,the velocity of the water jet in the central region *** comparison with experimental results,it is shown that the simulation model can accurately predict the impact position of the high-pressure water on the impact plate,thereby providing a computational scheme that can be used to optimize the nozzle space layout and improve the slabs’descent effect for different rolling specifications.

关键词： High pressure water descaling flow field analysis FSI target distance strike range

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Frequency and size change of ice–snow avalanches in the central Himalaya:A case from the Annapurna II glacier

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Advances in Climate Change Research 2024年第3期15卷 464-475页

作者： Yao LI Yi-Fei cui jian-Sheng HAO Zheng-Tao ZHANG Hao WANG jian GUO Shuo-Fan WANG State Key Laboratory of Hydroscience and Engineering Department of Hydraulic EngineeringTsinghua UniversityBeijing 100084China Key Laboratory of Hydrosphere Sciences of the Ministry of Water Resources Beijing 100084China Key Laboratory of land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China School of National Safety and Emergency Management Beijing Normal UniversityBeijing 100875China Key Laboratory of Mountain Hazards and Earth Surface Process Institute of Mountain Hazards and EnvironmentChinese Academy of SciencesChengdu 610041China

Glaciers have retreated and shrunk in High Mountain Asia since the mid-20th century because of global warming,leading to glacier instability and hazardous iceesnow ***,the complex relationship between iceesnow avalanches and factors such as climate and potential triggers are difficult to understand because of the lack of observational ***,we addressed iceesnow avalanches on the Annapurna II glacier in Nepal,Central *** constructed an iceesnow avalanche history using long-term multi-source remote sensing images(1988-2021)and mapped the velocity fields of glaciers using cross-correlation analysis on SAR and optical ***,we investigated the impact of climate change and earthquakes on the frequency and size of iceesnow *** results demonstrate that the frequency of iceesnow avalanches has increased from 10 in 1988 to 27 in 2020,but the average area of iceesnow avalanche deposits has decreased by approximately 70%,from 3.4×10^(5) m^(2) in 1988 to 1.2×10^(5) m^(2) in *** evolutionary characteristic of ice avalanches is linked to the impact of glacier retreat(reduction in ice material supply)and increased activity under climate *** glacier movement velocity controls the size of iceesnow avalanches and can be set as an indicator for iceesnow avalanche *** the Annapurna Ⅱ glacier,an iceesnow avalanche occurred when the glacier velocities were greater than 1.5 m d^(-1).These results offer insights into iceesnow avalanche risk assessment and prediction in high-mountain areas,particularly in regions characterised by dense glacier distribution.

关键词： Iceesnow avalanche Glacier instability Climate change Central Himalaya Remote sensing

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Safety and efficacy of omalizumab for antihistamine-resistant chronic urticaria in children:a case series and literature review

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World Journal of Pediatrics 2024年第3期20卷 294-298页

作者： Wei-Fang Zhu Chen Wang jian-Jun Qiao lan-Juan Li Department of Dermatology First Affiliated HospitalZhejiang University School of MedicineHangzhou 310003China State Key Laboratory for Diagnosis and Treatment of Infectious Diseases National Clinical Research Center for Infectious DiseasesCollaborative Innovation Center for Diagnosis and Treatment of Infectious DiseasesThe First Affiliated HospitalZhejiang University School of MedicineHangzhou 310003China

Chronic urticaria(CU)is a common skin disease characterized by the occurrence of wheals,with or without angioedema,lasting more than 6 *** prevalence of CU is about 0.7%[1],but higher in children,with an incidence of 1.38%[1].The occurrence of severe pruritus and unpredictable wheals may severely impact patients'quality of life,cause psychological problems,including sleep disorders and depression,and lead to economic burden due to limitation on daily life and work[2,3].

关键词： edema prevalence children

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The response and anti-stress mechanisms of nitrifying sludge under long-term exposure to Cd Se quantum dots

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Journal of Environmental Sciences 2024年第1期135卷 174-184页

作者： Linkai Guo Lei Yang Yongxiang Ren Shen cui Xiaotong Li Jia Wang Jun lan Haoqi Lu Yuchao Wang Shaanxi Key Laboratory of Environmental Engineering Xi’an University of Architecture and TechnologyXi’an 710055China Key Lab of Northwest Water Resource Environment and EcologyMinistry of EducationXi’an University of Architecture and TechnologyXi’an 710055China

The wide application of CdSe quantum dots(QDs)increases its stress risk to sewage treatment *** study evaluated the response of nitrification performance,floc characteristics and microbial community of nitrifying sludge under long-term exposure to CdSe *** showed CdSe QDs(≥1 mg/L)would decrease the activity of ammonia monooxygenase(AMO).Under the stress of 30 mg/L CdSe QDs,the activity of AMO was reduced by 66%,while the activities of hydroxylamine oxidase and nitrite oxidoreductase were enhanced by 19.1%and 26%,***,the final nitrification effects were not adversely affected,and the production rates of NO_(2)^(-)-N and NO_(3)^(-)-N were ***,CdSe QDs improved biomass concentration in sludge and maintained the stability of sludge *** throughput sequencing analysis showed that CdSe QDs evidently reduced the abundance and diversity of microbial community in nitrifying *** abundances of amino acid metabolism and lipid metabolism were ***,CdSe QDs decreased the fluorescence intensity of tryptophan-like protein from 2,326 to 1,179 *** loosely bound extracellular polymeric substances(EPSs)and from 3,792 to 3,117 *** tightly bound *** relieve CdSe QD stress,the polysaccharide content increased from0.31 to 0.61 mg/g MLSS and intracellular antioxidant defense was *** CdSe QD level increasing to 30 mg/L,the total antioxygenic capacity and the activities of catalase were enhanced up to 411%and 143.2%,***,CdSe QDs had little adverse effects on cell membrane integrity,microbial metabolism and the abundance of Nitrospirae.

关键词： Quantum dots Activated sludge Extracellular polymeric substances Microbial community Antioxidant effect

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Missing microbes in infants and children in the COVID-19 pandemic:a study of 1,126 participants in Beijing,China

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Science China(Life Sciences) 2024年第8期67卷 1739-1750页

作者： Jiejing Wang Yuejuan Li Yu Mu Kefei Huang Danyi Li Canhui lan Yutao cui Jun Wang CAS Key Lab for Pathogenic Microbiology and Immunology Institute of MicrobiologyChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China Beijing Dr.cuiYUTAO Clinic Beijing 100028China R-Institute Co.Ltd. Beijing 100011China

The COVID-19 pandemic has caused many fatalities worldwide and continues to affect the health of the recovered patients in the form of *** this study,we compared the gut microbiome of uninfected infants and children before the pandemic began(BEFORE cohort,n=906)to that of after the pandemic(AFTER cohort,n=220)to examine the potential impact of social distancing and life habit changes on infant/children gut *** on 16S rRNA sequencing,we found a significant change in microbiome composition after the pandemic,with Bacteroides enterotype increasing to 35.45%from 30.46%before the *** quantification indicated that the bacterial loads of seven keystone taxa decreased by 91.69%–19.58%.Quantitative microbiome profiling,used to enhance the resolution in detecting microbiome differences,revealed a greater explained variance of pandemic on microbiome compared to gender,as well as a significant decrease in bacterial loads in 15 of the 20 major *** random forest age-predictor indicated the gut microbiomes were less mature in the after-pandemic cohort than in the before-pandemic cohort in the children group(3–12 years old)and had features of a significantly younger age(average of 1.86 years).Lastly,body weight and height were significantly lower in the after-pandemic cohort than in the before-pandemic cohort in infants(<1 year of age),which was associated with a decrease in bacterial loads in the fecal microbiome.

关键词： gut microbiome COVID-19 pandemic quantitative microbiome profiling children health

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Regulation of Ti(C,N)deposition on hot surface of refractory in blast furnace hearth

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Journal of Iron and Steel Research(International) 2024年第6期31卷 1423-1435页

作者： jian Cao cui Wang Jjan-liang Zhang Ke-xin Jiao Guo-hua Zhang State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China

Ti(C,N)concentration was found to be lower on the hearth sidewall of a blast furnace and increased gradually toward the bottom of the blast *** Ti(C,N)protective layer in a blast furnace is ***,the formation of a Ti(C,N)protective layer was promoted by studying the heterogeneous nucleation principle of titanium compounds on different substances and regulation measures for the deposition process of titanium compounds on refractories or *** lattice disregistry between the titanium compounds and the main components in the refractory or the main impurities in the protective layer was calculated using a two-dimensional disregistry equation to study the heterogeneous nucleation principle of titanium *** results revealed that in refractory materials,the heterogeneous nucleation of carbonitride is weak when C,SiO_(2),and Al_(2)O_(3) are used as heterogeneous nucleation substrates,and the heterogeneous nucleation of carbonitride is strong when TiO_(2) and SiC are used as heterogeneous nucleation *** nucleation phases,TiC,TiN,Ti(C_(0.3),N_(0.7)),and Ti(C_(0.5),N_(0.5))have similar heterogeneous nucleation ability in single component refractory,and the type of carbonitride has little effect on the lattice *** impurities in the protective layer as the substrate phases are not conducive to the heterogeneous nucleation of *** CaS was used as the substrate phase,the heterogeneous nucleation ability of carbonitride was the *** carbon and alumina were not conducive to the heterogeneous nucleation of carbonitride,but carbon was more unfavourable than alumina.

关键词： Ti(C,N) Lattice disregistry Lattice constant Heterogeneous nucleation Regulation measure

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Molecularly imprinted sensor based on carboxylated carbon nanotubes/Keggin-type polyoxometalates nanocomposite for the detection of furazolidone

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Tungsten 2024年第2期6卷 394-409页

作者： Yu-lan Huang Bing Zhang Yu-Lian Li Li Wang Le Dong jian Li College of Ocean Food and Biological Engineering Jimei UniversityXiamen 361021China College of Oceanology and Food Science Quanzhou Normal UniversityQuanzhou 362000China

Due to its properties of mutagenic,teratogenic,and carcinogenic,the detection of furazolidone(FZD)in aquaculture is of great importance for food safety and human *** this study,molecularly imprinted fi lms modifi ed with carboxylated multi-walled carbon nanotube-phosphomolybdic acid composite were used to fabricate an electrochemical sensor for the determination of *** nanocomposites were characterized using infrared spectroscopy,scanning electron microscopy,energy-dispersive X-ray spectroscopy,and X-ray diff *** electrochemical characteristics of the modifi ed electrodes were examined using electrochemical impedance spectroscopy,cyclic voltammetry,and diff erential pulse *** sensor exhibited exceptional catalytic *** calibration curves were acquired in the concentration range of 6 nmol·L^(−1)to 0.6μmol·L^(−1),with a limit of detection of 3.38 nmol·L^(−1).Additionally,the sensor proved successful in recognizing FZD in shrimp samples with satisfactory recoveries and *** method provides a strategy to construct a molecularly imprinted electrochemical sensing platform using nanomaterials,which has great promise in the field of food safety.

关键词： Phosphomolybdate Furazolidone Polyoxometalates Carboxylated multi-walled carbon nanotube Molecularly imprinted polymers Electrochemical sensor

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Anchoring heterometallic cluster on P-doped carbon nitride for efficient photocatalytic nitrogen fixation in water and air ambient

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Chinese Chemical Letters 2024年第4期35卷 176-180页

作者： Chao-Long Chen Rong Chen La-Sheng Long lan-Sun Zheng Xiang-jian Kong Collaborative Innovation Center of Chemistry for Energy Materials State Key Laboratory of Physical Chemistry of Solid Surfaces and Department of ChemistryCollege of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China

Light-driven nitrogen fixation to produce ammonia is a green and economical technology of nitrogen reduction but is still quite challenging, especially in an air atmosphere without any sacrificial ***, we demonstrate efficient photocatalytic nitrogen fixation using water and air directly by loading lanthanide–transition metal(4f–3d) cluster NdCo_(3) on two-dimensional P-doped graphitic carbon nitrides(PCN) material surface. Benefiting from the increase in the number of nitrogen vacancies(NVs) and highly matched band gap structure and excellent hole trapping ability of clusters, the NdCo_(3)/PCN photocatalyst exhibits efficient nitrogen reduction activity with 371(in air) and 825 μmol h^(-1)g^(-1)(in pure nitrogen)without any sacrificial reagents. The introduction of potassium sulfate inhibits hydrogen production and promotes nitrogen reduction activation. This work suggests that anchoring precisely structured clusters on 2D materials may enhance photocatalytic nitrogen reduction under normal temperature and pressure.

关键词： Photocatalytic Nitrogen fixation 4f-3d Cluster Air atmosphere

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Network analysis reveals context-dependent structural complexity of social calls in serrate-legged small treefrogs

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Current Zoology 2024年第2期70卷 253-261页

作者： Ke Deng Qiao-Ling He Tong-Liang Wang Ji-Chao Wang jian-Guo cui CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization&Ecological Restoration and Biodiversity Conservation Key Laboratory of Sichuan Province Chengdu Institute of BiologyChinese Academy of SciencesChengdu 610041China University of Chinese Academy of Science Beijing 100049China Ministry of Education Key Laboratory for Ecology of Tropical lslands Key Laboratory of Tropical Animal and Plant Ecology of Hainan ProvinceCollege of Life SciencesHainan Normal UniversityHaikou 571158China

Vocal communication plays an important role in survival,reproduction,and animal social *** and mammals produce com-plex vocal sequence to convey context-dependent *** are conspicuous features of the behavior of most anuran species(frogs and toads),and males usually alter their calling strategies according to ecological context to improve the attractiveness/***,very few studies have focused on the variation of vocal sequence in *** the present study,we used both conventional method and network analysis to investigate the context-dependent vocal repertoire,vocal sequence,and call network structure in serrate-legged small treefrogs Kurixalus *** found that male *** modified their vocal sequence by switching to different call types and increasing repertoire size in the presence of a competitive ***,compared with before and after the playback of advertisement calls,males emited fewer advertisement calls,but more aggressive calls,encounter calls,and compound calls during the playback *** analysis revealed that the mean degree,mean closeness,and mean betweenness of the call networks significantly decreased during the playback period,which resulted in lower *** addition,the increased proportion of one-way motifs and average path length also indicated that the connectivity of the call network decreased in competitive ***,the vocal sequence of *** did not display a clear small-world network structure,regardless of *** study presents a paradigm to apply network analysis to vocal sequence in anurans and has important implications for understanding the evolution and function of sequence patterns.

关键词： call network centrality Kurixalus odontotarsus vocal repertoire vocal sequence.

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