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Origin and evolution of false brinelling and fretting corrosion under rolling conditions

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Friction 2024年第4期12卷 618-631页

作者： Xin JIA Lu HUANG miao sun Wenbin LI National Institute of Metrology Beijing 100029China Yantai Tiancheng Machinery Co. Ltd.Yantai 264006China

Rolling bearings working in oscillating applications often suffer from false brinelling and fretting corrosion that limit their service life.At present,the study of oscillation-induced failures is primarily dominated by a large number of sliding and bench tests.However,most of the previous work are not able to fully describe the two closely related but different failure mechanisms.In this study,the origin and evolution of the two failures are thoroughly investigated under strictly controlled oscillating rolling conditions.The results show that failure evolves from false brinelling to fretting corrosion under dry friction conditions regardless of the oscillation amplitude.This process is accompanied by a large area peeling and serious oxidation,and the oxygen content increases from 2.50 wt%to 21.22 wt%.Oxidation is a crucial factor in the evolution of false brinelling into fretting corrosion.However,the distribution of microwear and oxygen content depend on the oscillation amplitude.Under lubrication conditions,the friction coefficient(COF)is smaller in the initial stage and led to local slip or transient instability of rolling elements.Therefore,the size of the wear marks and COF increased and appeared to be larger than those under a dry friction condition.However,grease can separate the contact surfaces,only surface deformation owing to false brinelling and slight damage at the roughness level occurred.The evolution of false brinelling and fretting corrosion is also closely related to residual stress.False brinelling often occurrs with residual stress accomulation,meanwhile,the residual stress increases from 120 to 300 MPa.When peeling occurs,residual stress is released.The failure pattern transformed from false brinelling to fretting corrosion and is accompanied by oxidation.So far,none of investigation is able to show satisfactory evolution of oscillating-induced failures,this study may contribute to more scientific understanding of rolling bearings against long-run reciprocating oscillating wear.

关键词： oscillating false brinelling fretting corrosion wear residual stress

Nanofluidic memristor based on the elastic deformation of nanopores with nanoparticle adsorption

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National Science Review 2024年第4期11卷 46-54页

作者： Xi Zhou Yuanyuan Zong Yongchang Wang miao sun Deli Shi Wei Wang Guanghua Du Yanbo Xie Department of Chemistry and Chemical Engineering Northwestern Polytechnical University School of Physical Science and Technology Northwestern Polytechnical University School of Aeronautics and Institute of Extreme Mechanics Northwestern Polytechnical University Institute of Modern Physics Chinese Academy of Sciences

The memristor is the building block of neuromorphic computing. We report a new type of nanofluidic memristor based on the principle of elastic strain on polymer nanopores. With nanoparticles absorbed at the wall of a single conical polymer nanopore, we find a pinched hysteresis of the current within a scanning frequency range of 0.01–0.1 Hz, switching to a diode below 0.01 Hz and a resistor above 0.1 Hz. We attribute the current hysteresis to the elastic strain at the tip side of the nanopore, caused by electrical force on the particles adsorbed at the inner wall surface. Our simulation and analytical equations match well with experimental results, with a phase diagram for predicting the system transitions. We demonstrate the plasticity of our nanofluidic memristor to be similar to a biological synapse. Our findings pave a new way for ionic neuromorphic computing using nanofluidic memristors.

关键词： nanofluidics memristor neurocomputing elastic deformation

MicroRNA-146a-loaded magnesium silicate nanospheres promote bone regeneration in an inflammatory microenvironment

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Bone Research 2024年第1期12卷 153-164页

作者： Jiakang Yang Jing Shuai Lixuen Siow Jingyi Lu miao sun Wenyue An Mengfei Yu Baixiang Wang Qianming Chen Stomatology Hospital School of StomatologyZhejiang University School of MedicineZhejiang Provincial Clinical Research Center for Oral DiseasesKey Laboratory of Oral Biomedical Research of Zhejiang ProvinceCancer Center of Zhejiang UniversityHangzhou 310000China

Reconstruction of irregular oral-maxillofacial bone defects with an inflammatory microenvironment remains a challenge,as chronic local inflammation can largely impair bone healing.Here,we used magnesium silicate nanospheres(MSNs)to load microRNA-146a-5p(miR-146a)to fabricate a nanobiomaterial,MSN+miR-146a,which showed synergistic promoting effects on the osteogenic differentiation of human dental pulp stem cells(hDPSCs).In addition,miR-146a exhibited an anti-inflammatory effect on mouse bone marrow-derived macrophages(BMMs)under lipopolysaccharide(LPS)stimulation by inhibiting the NF-κB pathway via targeting tumor necrosis factor receptor-associated factor 6(TRAF6),and MSNs could simultaneously promote M2 polarization of BMMs.MiR-146a was also found to inhibit osteoclast formation.Finally,the dual osteogenic-promoting and immunoregulatory effects of MSN+miR-146a were further validated in a stimulated infected mouse mandibular bone defect model via delivery by a photocuring hydrogel.Collectively,the MSN+miR-146a complex revealed good potential in treating inflammatory irregular oralmaxillofacial bone defects.

关键词： inflammatory healing stimulation

A novel homozygous missense variant in ARSK causes MPS X,a new subtype of mucopolysaccharidosis

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Genes & Diseases 2024年第3期11卷 87-90页

作者： miao sun Cornelia K.Kaminsky Philip Deppe Mai-Brittllse Frederic M.Vaz Barbara Plecko Torben Lubke Linda M.Randolph Division of Genomic Medicine Department of Pathology and Laboratory MedicineChildren's Hospital Los Angeles/Keck School of Medicine of USCLos AngelesCA 90027USA Department of Radiology Children's Hospital Los Angeles/Keck School of Medicine of USCLos AngelesCA 90027USA Department of Chemistry BiochemistryBielefeld UniversityBielefeld 33615Germany Amsterdam UMC Location University of Amsterdam Department of Clinical Chemistry and PediatricsLaboratory Genetic Metabolic DiseasesEmma Children's HospitalMeibergdreef 9Amsterdam 1100 DEthe Netherlands Amsterdam Gastroenterology Endocrinology Metabolism Inborn Errors of MetabolismAmsterdam 1105 BKthe Netherlands Core Facility Metabolomics Amsterdam UMC Location University of AmsterdamAmsterdam 1100DDthe Netherlands Department of Pediatrics Division of General PediatricsMedical Universityof GrazGraz8036Austria Division of Medical Genetics Department of PediatricsChildren's Hospital Los Angeles/Keck School of Medicine of USCLos AngelesCA 90027USA

Mucopolysaccharidoses(MPS)are a group of rare inborn errors of metabolism caused by defective lysosomal enzymes which prevent cells from degrading and recycling certain carbohydrates and fats,resulting in the storage of glycosaminoglycans in cells throughout the body.This leads to multisystem abnormalities involving bone,connective tissues,brain,blood,spinal cord,skin,and other tissues.

关键词： metabolism doses polys

A combined evaluation of the characteristics and antibiotic resistance induction potential of antibiotic wastewater during the treatment process

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Journal of Environmental Sciences 2024年第4期138卷 626-636页

作者： sun miao Yanyan Zhang Cong Men Yiou Mao Jiane Zuo State Key Joint Laboratory of Environment Simulation and Pollution Control School of EnvironmentTsinghua UniversityBeijing 100084China School of Energy and Environmental Engineering Beijing Key Laboratory of Resource-Oriented Treatment of Industrial PollutantsUniversity of Science and Technology BeijingBeijing 100083China High School Affiliated to Renmin University of China Beijing 100080China Tsinghua Shenzhen International Graduate School Shenzhen 518055China

Antibiotic wastewater contains a variety of pollutant stressors that can induce and promote antibiotic resistance(AR)when released into the environment.Although these substances are mostly in concentrations lower than those known to induce AR individually,it is possible that antibiotic wastewater discharge might still promote the AR transmission risk via additive or synergistic effects.However,the comprehensive effect of antibiotic wastewater on AR development has rarely been evaluated,and its treatment efficiency remains unknown.Here,samples were collected from different stages of a cephalosporin production wastewater treatment plant,and the potential AR induction effect of their chemical mixtures was explored through the exposure of the antibiotic-sensitive Escherichia coli K12 strain.Incubation with raw cephalosporin production wastewater significantly promoted mutation rates(3.6×10^(3)-9.3×10^(3)-fold)and minimum inhibition concentrations(6.0-6.7-fold)of E.coli against ampicillin and chloramphenicol.This may be attributed to the inhibition effect and oxidative stress of cephalosporin wastewater on E.coli.The AR induction effect of cephalosporin wastewater decreased after the coagulation sedimentation treatment and was completely removed after the full treatment process.A Pearson correlation analysis revealed that the reduction in the AR induction effect had a strong positive correlation with the removal of organics and biological toxicity.This indicates that the antibiotic wastewater treatment had a collaborative processing effect of conventional pollutants,toxicity,and the AR induction effect.This study illustrates the potential AR transmission risk of antibiotic wastewater and highlights the need for its adequate treatment.

关键词： Antibiotic wastewater treatment plant Antibiotic resistance Antibiotic resistance induction effect Correlation analysis Biological toxicity

Hydrometallurgical recovery of lithium carbonate and iron phosphate from blended cathode materials of spent lithium-ion battery

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Rare Metals 2024年第3期43卷 1275-1287页

作者： Shao-Le Song Run-Qing Liu miao-miao sun Ai-Gang Zhen Fan-Zhen Kong Yue Yang School of Minerals Processing and Bioengineering Central South UniversityChangsha410083China Zhejiang Tianneng New Materials Co. Ltd.Huzhou313103China

The recycling of cathode materials from spent lithium-ion battery has attracted extensive attention,but few research have focused on spent blended cathode materials.In reality,the blended materials of lithium iron phosphate and ternary are widely used in electric vehicles,so it is critical to design an effective recycling technique.In this study,an efficient method for recovering Li and Fe from the blended cathode materials of spent LiFePO_(4)and LiNi_(x)Co_(y)Mn_(1-x-y)O_(2)batteries is proposed.First,87%A1 was removed by alkali leaching.Then,91.65%Li,72.08%Ni,64.6%Co and 71.66%Mn were further separated by selective leaching with H_(2)SO_(4)and H_(2)O_(2).Li,Ni,Co and Mn in solution were recovered in the form of Li_(2)CO_(3)and hydroxide respectively.Subsequently,98.38%Fe was leached from the residue by two stage process,and it is recovered as FePO_(4)·2H_(2)O with a purity of 99.5%by precipitation.Fe and P were present in FePO_(4)·2H_(2)O in amounts of 28.34%and 15.98%,respectively.Additionally,the drift and control of various components were discussed,and cost-benefit analysis was used to assess the feasibility of potential application.

关键词： Spent lithium-ion battery Blended cathode materials Recovery Lithium carbonate Iron phosphate

Spatiotemporal variations,influencing factors,and configurational promotion paths of energy efficiency in China’s cities

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Chinese Journal of Population,Resources and Environment 2024年第1期22卷 74-86页

作者： Ruyu Xu Keliang Wang Zhuang miao Lingxuan sun School of Economics Ocean University of ChinaQingdao 266011China China Western Economic Research Center Southwestern University of Finance and EconomicsChengdu 611130China School of Economics and Management Southwest Petroleum UniversityChengdu 610500China

The promotion of energy efficiency(EE)helps address energy constraints and promote environmental sustainability.This study comprehensively explores the spatiotemporal variations,influencing factors,and configuration promotion paths of EE in 284 Chinese cities during 2003‒2019 using the global super-efficiency minimum distance to strong efficient frontier(G-S-MinDS),exploratory spatial data analysis(ESDA),multiscale geographically weighted regression(MGWR),and fuzzy set qualitative comparative analysis(fsQCA)methods.The findings are:①China’s cities have an annual average EE of 0.658 with a growth rate of 0.53%,showing considerable promotion potential.②Industrial structure optimization,population agglomeration,economic development,and increased green coverage contribute positively,while government intervention and openness hinder China’s urban EE.③Four configurational promotion paths for enhancing China’s urban EE are identified,where among those paths population density is a core condition,while government intervention is not.This study provides valuable insights into substantially improving urban EE,emphasizing the need for targeted policies to address energy and environmental crises in China.

关键词： Energy efficiency Spatiotemporal variations Influencing factors Configurational promotion paths

An all-in-one FeO_(x)-rGO sponge fabricated by solid-phase microwave thermal shock for water evaporation and purification

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Journal of Environmental Sciences 2024年第4期138卷 671-683页

作者： Youkun sun Xiuwen Zhao Xueling Song Jinchen Fan Junhe Yang Yingchun miao Shuning Xiao School of Materials and Chemistry University of Shanghai for Science and TechnologyShanghai 200093China College of Chemistry and Environmental Science Qujing Normal UniversityQujing 655011China Prytula Igor Collaborate Innovation Center for Diamond Shanghai Jian Qiao UniversityShanghai 201306China

Developing high-efficiency photothermal seawater desalination devices is of significant importance in addressing the shortage of freshwater.Despite much effort made into photothermal materials,there is an urgent need to design a rapidly synthesized photothermal evaporator for the comprehensive purification of complex seawater.Therefore,we report on all-in-one FeOx-rGO photothermal sponges synthesized via solid-phase microwave thermal shock.The narrow band gap of the semiconductor material Fe_(3)O_(4) greatly reduces the recombination of electron-hole pairs,enhancing non-radiative relaxation light absorption.The abundantπorbitals in rGO promote electron excitation and thermal vibration between the lattices.Control of the surface hydrophilicity and hydrophobicity promotes salt resistance while simultaneously achieving the purification of various complex polluted waters.The optimized GFM-3 sponge exhibitedan enhanced photothermal conversion rate of 97.3% and a water evaporation rate of 2.04 kg/(m^(2)·hr),showing promising synergistic water purification properties.These findings provide a highly efficient photothermal sponge for practical applicationsof seawater desalination and purification,as well as develop a super-rapid processing methodology for evaporation devices.

关键词： Desalination Photothermal device Microwave synthesis Water purification FeO_(x)-rGO

Health risk assessment of trace metal(loid)s in agricultural soils based on Monte Carlo simulation coupled with positive matrix factorization model in Chongqing, southwest China

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Journal of Mountain Science 2024年第1期21卷 100-112页

作者： MA Jie CHU Lijuan sun Jing WANG Shenglan GE miao DENG Li Chongqing Ecological and Environmental Monitoring Center Chongqing 401147China Key Laboratory of Organic Pollutants in Environmental Chemical Behavior and Ecological Toxicology of Chongqing Chongqing 401147China Department of Pediatrics Chongqing Health Center for Women and ChildrenChongqing 401147China Department of Pediatrics Women and Children’s Hospital of Chongqing Medical UniversityChongqing 401147China

This study aimed to investigate the pollution characteristics, source apportionment, and health risks associated with trace metal(loid)s(TMs) in the major agricultural producing areas in Chongqing, China. We analyzed the source apportionment and assessed the health risk of TMs in agricultural soils by using positive matrix factorization(PMF) model and health risk assessment(HRA) model based on Monte Carlo simulation. Meanwhile, we combined PMF and HRA models to explore the health risks of TMs in agricultural soils by different pollution sources to determine the priority control factors. Results showed that the average contents of cadmium(Cd), arsenic (As), lead(Pb), chromium(Cr), copper(Cu), nickel(Ni), and zinc(Zn) in the soil were found to be 0.26, 5.93, 27.14, 61.32, 23.81, 32.45, and 78.65 mg/kg, respectively. Spatial analysis and source apportionment analysis revealed that urban and industrial sources, agricultural sources, and natural sources accounted for 33.0%, 27.7%, and 39.3% of TM accumulation in the soil, respectively. In the HRA model based on Monte Carlo simulation, noncarcinogenic risks were deemed negligible(hazard index <1), the carcinogenic risks were at acceptable level(10^(-6)

关键词： Monte Carlo simulation Health risk assessment Trace metal(loid)s Positive matrix factorization Agricultural soils