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Phase transition of multi-component(TiZrVNb)C ceramics—Part I:Phase decomposition induced by carbon content

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Journal of Advanced Ceramics 2024年第5期13卷 679-688页

作者： Qingyi Kong rao Zhang Lei Chen Sijia Huo Wenyu Lu Yujin Wang Boxin Wei Yu Zhou Institute for Advanced Ceramics School of Materials Science and EngineeringHarbin Institute of TechnologyHarbin 150080China Key Laboratory of Advanced Structure‒Function Integrated Materials and Green Manufacturing Technology Harbin Institute of TechnologyHarbin 150001China School of Materials Science and Chemical Engineering Harbin University of Science and TechnologyHarbin 150001China National Key Laboratory of Precision Hot Processing of Metals Harbin Institute of TechnologyHarbin 150001China

Phase decomposition can effectively enhance the mechanical properties of carbide ceramics and can overcome the difficulty of enhancing the mechanical properties of single-phase multicomponent carbide *** this work,a series of nonstoichiometric(TiZrVNb)Cx ceramics were prepared by spark plasma sintering(SPS)at different *** effects of the carbon content on the phase composition,microstructure evolution,and mechanical properties were investigated in *** decomposition occurred with decreasing carbon *** different solid solutions of(Ti,V)-rich and Zr-rich phases formed from the decomposition of equimolar single-phase solid solutions,namely,the Zr-poor phase and Zr-rich phase,*** distribution of Nb element is relatively *** semicoherent interfaces between the Zr-poor phase and the Zr-rich phase can harden and strengthen effectively under the synergistic effect of grain *** with phase decomposition structures have apparent advantages compared to single-phase high-entropy *** work provides an important train of thought for the microstructure tailoring and properties optimization of multi-component carbide ceramics.

关键词： multicomponent ceramics nontoichiometry microstructure evolution phase decomposition mechanical properties

regulating the electronic structure of Ir single atoms by ZrO_(2)nanoparticles for enhanced catalytic oxidation of formaldehyde at room temperature

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Chinese Chemical Letters 2024年第7期35卷 200-205页

作者： Shiqi Peng Yongfang rao Tan Li Yufei Zhang Jun-ji Cao Shuncheng Lee Yu Huang Key Laboratory of Aerosol Chemistry&Physics State Key Laboratory of Loess and Quaternary Geology(SKLLQG)Institute of Earth EnvironmentChinese Academy of Sciences(CAS)Xi’an 710061China School of Human Settlements and Civil Engineering Xi’an Jiaotong UniversityXi’an 710049China Department of Environmental Science and Engineering Xi’an Jiaotong UniversityXi’an 710049China Faculty of Chemical Engineering Kunming University of Science and TechnologyKunming 650500China School of Environment and Energy South China University of TechnologyGuangzhou 51006China School of Environmental and Municipal Engineering Xi’an University of Architecture and TechnologyXi’an 710055China Institute of Atmospheric Physics Chinese Academy of SciencesBeijing 100190China Department of Civil and Environmental Engineering The Hong Kong Polytechnic UniversityHong KongChina CAS Center for Excellence in Quaternary Science and Global Change Xi’an 710061China

Developing low-loading single-atom catalysts with superior catalytic activity and selectivity in formaldehyde(HCHO)oxidation at room temperature remains ***,ZrO_(2)nanoparticles coupled low-loading Ir single atoms in N-doped carbon(Ir_(1)-N-C/ZrO_(2))was *** optimal Ir_(1)-N-C/ZrO_(2)with 0.25 wt%Ir loading delivers the high HCHO removal and conversion efficiency(>95%)at 20℃,which is higher than that over Ir_(1)-N-C with the same Ir *** specific rate can reach 1285.6 mmol gIr^(-1)h^(-1),surpassing the Ir based catalysts reported to *** functional theory calculation results and electron spin resonance spectra indicate that the introduction of Zr O_(2)nanoparticles modulate the electronic structure of the Ir single atoms,promoting O_(2)activation to·O_(2)^(–).Moreover,the Ir-C-Zr channel is favorable for the dissociation of·O_(2)^(–)to active oxygen atom(*O),and further accelerates the transformation of HCHO and intermediates(dioxymethylene and formates)to CO_(2)and H_(2)*** work provides a facile strategy to design low-loading single-atom catalysts with high catalytic activity toward HCHO oxidation.

关键词： ZrO_(2)nanoparticles Ir single atoms Electronic structure Formaldehyde Catalytic oxidation

Oxidation behavior of FeV_(2)O_(4)and FeCr_(2)O_(4)particles in the air:Nonisothermal kinetic and reaction mechanism

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International Journal of Minerals,Metallurgy and Materials 2024年第8期31卷 1839-1848页

作者： Junyi Xiang Xi Lu Luwei Bai Hongru rao Sheng Liu Qingyun Huang Shengqin Zhang Guishang Pei Xuewei Lü School of Metallurgy and Materials Engineering Chongqing University of Science and TechnologyChongqing 401331China Department of Materials Science and Engineering Seoul National UniversitySeoul 08826Rep.of Korea College of Materials Science and Engineering Chongqing UniversityChongqing 400044China

High-temperature oxidation behavior of ferrovanadium(FeV_(2)O_(4))and ferrochrome(FeCr_(2)O_(4))spinels is crucial for the application of spinel as an energy material,as well as for the clean usage of high-chromium vanadium ***,the nonisothermal oxidation behavior of FeV_(2)O_(4)and FeCr_(2)O_(4)prepared by high-temperature solid-state reaction was examined by thermogravimetry and X-ray diffraction(XrD)at heating rates of 5,10,and 15 K/*** apparent activation energy was determined by the Kissinger-Akahira-Sunose(KAS)method,whereas the mechanism function was elucidated by the Malek ***,in-situ XrD was conducted to deduce the phase transformation of the oxidation mechanism for FeV_(2)O_(4)and FeCr_(2)O_(4).The results reveal a gradual increase in the overall apparent activation energies for FeV_(2)O_(4)and FeCr_(2)O_(4)during *** stages of the oxidation process are observed based on the oxidation conversion rate of each *** oxidation mechanisms of FeV_(2)O_(4)and FeCr_(2)O_(4)are complex and have distinct *** particular,the chemical reaction controls the entire oxidation process for FeV_(2)O_(4),whereas that for FeCr_(2)O_(4)transitions from a three-dimensional diffusion model to a chemical reaction *** to the in-situ XrD results,numerous intermediate products are observed during the oxidation process of both compounds,eventually resulting in the final products FeVO_(4)and V2O_(5)for FeV_(2)O_(4)and Fe_(2)O_(3)and Cr_(2)O_(3)for FeCr_(2)O_(4),respectively.

关键词： FeV_(2)O_(4) FeCr_(2)O_(4) oxidation nonisothermal kinetics mechanism

Selective leaching of lithium from spent lithium-ion batteries using sulfuric acid and oxalic acid

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International Journal of Minerals,Metallurgy and Materials 2024年第4期31卷 688-696页

作者： Haijun Yu Dongxing Wang Shuai rao Lijuan Duan Cairu Shao Xiaohui Tu Zhiyuan Ma Hongyang Cao Zhiqiang Liu Institute of Advanced Wear&Corrosion resistant and Functional Materials Jinan UniversityGuangzhou 510632China Institute of resources Utilization and rare Earth Development Guangdong Academy of SciencesGuangzhou 510650China State Key Laboratory of Separation and Comprehensive Utilization of rare Metals Guangzhou 510650China Guangdong Province Key Laboratory of rare Earth Development and Application Guangzhou 510650China

Traditional hydrometallurgical methods for recovering spent lithium-ion batteries(LIBs)involve acid leaching to simultaneously extract all valuable metals into the *** methods usually are followed by a series of separation steps such as precipitation,extraction,and stripping to separate the individual valuable *** this study,we present a process for selectively leaching lithium through the synergistic effect of sulfuric and oxalic *** optimal leaching conditions(leaching time of 1.5 h,leaching temperature of 70°C,liquid-solid ratio of 4 mL/g,oxalic acid ratio of 1.3,and sulfuric acid ratio of 1.3),the lithium leaching efficiency reached89.6%,and the leaching efficiencies of Ni,Co,and Mn were 12.8%,6.5%,and 21.7%.X-ray diffraction(XrD)and inductively coupled plasma optical emission spectrometer(ICP-OES)analyses showed that most of the Ni,Co,and Mn in the raw material remained as solid residue oxides and *** study offers a new approach to enriching the relevant theory for selectively recovering lithium from spent LIBs.

关键词： selective leaching oxalic acid sulfuric acid spent lithium-ion batteries

Extreme Weather Disruptions and Emergency Preparedness Among Older Adults in Ohio: An Eight-County Assessment

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International Journal of Disaster risk Science 2024年第2期15卷 213-225页

作者： Smitha rao Fiona C.Doherty Anthony Traver Marisa Sheldon Emma Sakulich Holly Dabelko‑Schoeny College of Social Work The Ohio State UniversityColumbusOH 43210USA Age Friendly Innovation Center College of Social WorkThe Ohio State UniversityColumbusOH 43210USA College of Public Health The Ohio State UniversityColumbusOH 43210USA

The disproportionate risks and impacts of climate change and extreme weather on older adults are increasingly evident. While especially true in disaster-prone areas, human-caused climate change introduces an element of uncertainty even in previously identified “safe” regions such as the Midwestern United States. Using a cumulative disadvantage and vulnerability-informed framework and descriptive statistics from multiple data sources, this article provides an overview of climate impacts, vulnerabilities, and county-level characteristics, focusing on older adults living in Central Ohio. A comparative multiple-case study methodology was used to triangulate regionally representative primary and secondary data sources to examine state and county-level measures of vulnerability, emergency preparedness, and disruptions caused by extreme weather among older adults across eight counties in Central Ohio. Seventy-eight percent of older adults in the sample reported being prepared for emergencies per Federal Emergency Management Agency guidelines. Older adults in Union County reported the highest rates of preparedness, while those in Fayette County reported the lowest. County-level rates of disruption of life activities by extreme weather ranged widely. Among the most rural in the region, Fayette County emerged as uniquely disadvantaged, with the lowest median income, the most vulnerable across multiple social vulnerability dimensions, and the most reported disruptions to life activities from extreme weather. County profiles offer a snapshot of existing vulnerabilities, socioeconomic conditions, special needs, preparedness, and current disruptions among older adults in the region and can inform resource mobilization across community and policy contexts.

关键词： Disaster preparedness Extreme weather Midwestern United States Older adults regional assessment Social vulnerability

Small extracellular vesicles from hypoxia-preconditioned bone marrow mesenchymal stem cells attenuate spinal cord injury via mir-146a-5p-mediated regulation of macrophage polarization

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Neural regeneration research 2024年第10期19卷 2259-2269页

作者： Zeyan Liang Zhelun Yang Haishu Xie Jian rao Xiongjie Xu Yike Lin Chunhua Wang Chunmei Chen Department of Neurosurgery Fujian Medical University Union HospitalFuzhouFujian ProvinceChina Fujian Neurosurgical Institute FuzhouFujian ProvinceChina

Spinal cord injury is a disabling condition with limited treatment *** studies have provided evidence suggesting that small extracellular vesicles(SEVs)secreted by bone marrow mesenchymal stem cells(MSCs)help mediate the beneficial effects conferred by MSC transplantation following spinal cord ***,hypoxia-preconditioned bone marrow mesenchymal stem cell-derived SEVs(HSEVs)exhibit increased therapeutic *** thus explored the role of HSEVs in macrophage immune regulation after spinal cord injury in rats and their significance in spinal cord *** or HSEVs were isolated from bone marrow MSC supernatants by density gradient *** administration to rats via tail vein injection after spinal cord injury reduced the lesion area and attenuated spinal cord *** regulate macrophage polarization towards the M2 phenotype in vivo and in *** rNA sequencing and bioinformatics analyses of SEVs and HSEVs revealed that mi r-146a-5p is a potent mediator of macrophage polarization that targets interleukin-1 receptor-associated kinase *** mi r-146a-5p expression in HSEVs partially attenuated macrophage *** data suggest that HSEVs attenuate spinal cord inflammation and injury in rats by transporting mi r-146a-5p,which alters macrophage *** study provides new insights into the application of HSEVs as a therapeutic tool for spinal cord injury.

关键词： bone marrow mesenchymal stem cells hypoxia preconditioning interleukin-1 receptor-associated kinase 1 macrophages mesenchymal stem cells small extracellular vesicles spinal cord injury

Vibrational Spectra of Distorted Structure Molecules by Using Lie Algebraic Techniques： an Application to Copper and Magnesium Octaethyl Porphyrin

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Chinese Physics Letters 2010年第10期27卷 80-83页

作者： srinivasa rao Karumuri School of Sciences and Humanities Sri Viveka Institute of Technology (SVIT) Madalavari Gudem Nunna Krihna District-521212 India

Using a U （2） algebraic model the fundamental stretching vibrations of copper octaethyl porphyrin and magnesium octaethyl porphyrin are calculated for 24 vibrational bands. The locality parameter ξ confirms the highly local behavior of the stretching modes of these porphyrin molecules. The model Hamiltonian so constructed appears to describe the vibrational energy levels accurately.

关键词： VIBrATIONAL spectra NUCLEAr structure LIE algebras COPPEr compounds POrPHYrINS MOLECULAr models

Ocean wave directional spectrum estimation using spatio-temporal array of acoustic ranging and current measurement

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Chinese Journal of Acoustics 2024年第3期43卷 311-331页

作者： rao Liang DENG Kai ZHANG Zhaowei WANG Changhong Institute of Acoustics Chinese Academy of SciencesBeijing100190 University of Chinese Academy of Sciences Beijing100049 Beijing Engineering Technology research Center of Ocean Acoustic Equipment Beijing100190

An approach to estimate ocean wave directional spectrum using spatio-temporal array of acoustic ranging and current measurement is proposed,and the 5-beam acoustic Doppler current profiler(ADCP)constructs a spatio-temporal array of acoustic ocean surface elevation tracking and acoustic Doppler current velocity measuring for directional wave *** on the linear wave theory and the space-time equivalence principle,the time-space transfer function applicable to the spatio-temporal array is proposed,and then the time delay term is compensated in the calculation of the covariance *** method can reduce the error of the directional spectrum *** results show that for the low signal-to-noise ratio from 0 dB to 5 dB,compared with the 4-beam synchronous array method,this method has a smaller root-mean-square error of the peak estimation of the directional *** field test shows that,compared with the 4-beam synchronous array method,the 5-beam spatio-temporal array method improves the kurtosis index of the directional spectrum from 2.31 to 2.80,and the correlation coefficient between the peak wave direction results of the ADCP and the buoy is increased from 0.80 to 0.83 in mild wave ***,the spatio-temporal array method can increase the degree of freedom of wave measurement,reduce the minimum aperture of the array,and increase the upper cut-off frequency of the estimable directional spectrum.

关键词： spectrum ocean directional

Detection of a temporal salient object benefits from visual stimulus-specific adaptation in avian midbrain inhibitory nucleus

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Integrative Zoology 2024年第2期19卷 288-306页

作者： Jiangtao WANG Xiaoping rao Shuman HUANG Zhizhong WANG Xiaoke NIU Minjie ZHU Songwei WANG Li SHI Department of Automation Zhengzhou University School of Electrical EngineeringZhengzhouChina State Key Laboratory of Magnetic resonance and Atomic and Molecular Physics National Center for Magnetic Resonance in WuhanKey Laboratory of Magnetic Resonance in Biological SystemsInnovation Academy for Precision Measurement Science and TechnologyChinese Academy of SciencesWuhanChina Department of Automation Tsinghua UniversityBeijingChina

Food and predators are the most noteworthy objects for the basic survival of wild animals,and both are often deviant in both spatial and temporal domains and quickly attract an animal’s *** stimulus-specific adaptation(SSA)is considered a potential neural basis of salient sound detection in the temporal domain,related research on visual SSA is limited and its relationship with temporal saliency is *** avian nucleus isthmi pars magnocellularis(Imc),which is central to midbrain selective attention network,is an ideal site to investigate the neural correlate of visual SSA and detection of a salient object in the time ***,the constant order paradigm was applied to explore the visual SSA in the Imc of *** results showed that the firing rates of Imc neurons gradually decrease with repetitions of motion in the same direction,but recover when a motion in a deviant direction is presented,implying visual SSA to the direction of a moving ***,enhanced response for an object moving in other directions that were not presented ever in the paradigm is also *** verify the neural mechanism underlying these phenomena,we introduced a neural computation model involving a recoverable synaptic change with a“center-surround”pattern to reproduce the visual SSA and temporal saliency for the moving *** results suggest that the Imc produces visual SSA to motion direction,allowing temporal salient object detection,which may facilitate the detection of the sudden appearance of a predator.

关键词： adaptation attention model pigeon saliency