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Size Dependent Mechanical Properties of Graphene Nanoribbons: Molecular Dynamics Simulation

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Size Dependent Mechanical Properties of Graphene Nanoribbons...

Riverine sulfate sources and behaviors in arid environment,Northwest China:Constraints from sulfur and oxygen isotopes

中国材料大会2012

作者： Y. J. Sun F. Ma k. W. xu State k.y Laboratory for Mechanical Behavior of Materials Xi'an Jiaotong University Department of Physics and Opt-electronic Engineering Xi'an University of Arts and Science

ISBN: (纸本)9783037856093

Strain engineering is an effective method to tune the band gap and electronic transport properties of graphene nanoribbons （GNRs）. However, strain/stress field may promote the system deviating from the equilibrium state, and the mechanical stability will become one of the k.y issues for reliable services of relevant devices. In this paper, the size-dependent mechanical properties of GNRs under tensile loading were studied by Molecular Dynamics （MD） simulations. The results indicate that the yield stress of both zigzag and armchair GNRs decreases with the ribbon length changing from 240 to 30 . However, the ductility of armchair GNRs was significantly improved. Radial Distribution Function （RDF） was employed to analyze the evolution of atomic configurations. It showed that lattice shearing is the main mechanism for the ductility of armchair GNRs.

关键词： Graphene nanoribbons Fracture stress Radial distribution function Lattice shearing

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Journal of Environmental Sciences 2024年第3期137卷 716-731页

作者： Yifu xu Wenjing Liu Bing xu Zhifang xu k.y Laboratory of Cenozoic Geology and Environment Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China Innovation Academy for Earth Science Chinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 100049China

The fate of riverine sulfate ion (SO_(4)^(2-)) and its environmental effects in arid environment are difficult to evaluate due to its complicated sources and strongly coupled behaviors with water cycle which is significantly modified by *** understand the sulfur cycle in aquatic systems in arid environment,the chemical and sulfur and oxygen isotopic compositions (δ^(34)S_(SO4)and δ^(18)O_(SO4)) of major rivers around the Badain Jaran Desert,northwestern China,were *** rivers had averaged SO_(4)^(2-)content at 1336μmol/L,over 10times higher than the global *** δ^(34)S_(SO4)and δ^(18)O_(SO4)values ranged from-5.3‰to+11.8‰and+1.6‰to+12.8‰,*** end-member analysis and the inverse model showed that riverine sulfate was mainly derived from evaporites dissolution (0-87%),sulfide oxidation (13%-100%) and precipitation (0-33%),indicating heterogeneity in sulfur sources and behaviors along the river drainage with the lithology variations and climate *** isotopic tools combining with hydro-chemistry compositions could be applied to reveal sulfur cycle in arid *** on the calculation,sulfide oxidation plays the primary role in the headwater and upstream in the Qilian-Mountains area,where sulfide is widely *** the proportion of evaporites dissolution contributing to riverine sulfate is much higher in downstream in a drier ***,less precipitation and higher temperature can lead to more intensive evaporation,affecting the process of sulfide oxidation and enhancing the rates of evaporites dissolution and sulfate precipitation in the basin.

关键词： Sulfur and oxygen isotopes Source apportionment Inverse model Arid environment Inland rivers Northwestern China

Structure and Mechanical Properties of Magnesium Alloy Treated by Plasma Electrolysis Oxidation Using Direct Current and High-frequency Bipolar Pulsing Modes

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Southwestern Institute of Physics Annual Report

Southwestern Institute of Physics Annual Report 2006年第1期 199-201页

作者： JIN Fanya Chu Paul k. xu Guidong ZHAO Jun SHEN Liru TONG Honghui

Magnesium （Mg） and its alloys are one of the lightest metals used in the construction, automotive, aerospace, and communications industries. Owing to its low density, high specific strength, and good cast and welding ability, interests in Mg and Mg alloy are proliferating rapidly. However, there are some inherent problems arising from their chemically active nature, such as poor corrosion resistance, friction, and wear characteristicst21. In order to improve these properties,. surface modification is a viable approach and techniques such as electrochemical plating, anodizing, physical vapor deposition （PVD）, and chemical vapor deposition （CVD） have been proposed

关键词：镁合金等离子体电解氧化高频率双级脉冲

Laboratory evaluation of high-friction thin overlays for pavement preservation

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Frontiers of Structural and Civil Engineering 2024年第6期18卷 936-948页

作者： Ouming xu Rentao xu Lintong JIN School of Highway Chang’an UniversityXi’an 710064China School of Materials Science and Engineering Chang’an UniversityXi’an 710061China

Traditional asphalt concrete(AC)and stone matrix asphalt(SMA),which are used as thin asphalt overlays,are common maintenance strategies to enhancing ride quality,sk.d resistance,and ***,several studies have used a novel asphalt mixture k.own as a high-friction thin overlay(HFTO)to improve surface ***,it remains uncertain whether the laboratory properties of HFTO differ significantly from those of conventional *** study aims to evaluate the laboratory properties of HFTO mixtures and compare them with those of AC and *** mixtures with nominal maximum size of 9.5 mm were produced in the laboratory,and performance tests were conducted,including wheel track.ng test,low temperature flexural creep test,moisture susceptibility test,Cantabro Abrasion Test,Marshall Test,sand patch test,British pendulum test,and indoor tire-rollingdown *** results showed that the HFTO exhibited a lower tire/pavement noise than the AC and ***,HFTO had superior high-temperature stability,larger macro texture,and higher sk.d resistance in comparison to those of AC,but lower than those of ***,HFTO mixtures may be considered a suitable replacement for traditional AC mixtures in regions where sk.d resistance and noise reduction are concerns.

关键词： road engineering pavement maintenance high friction thin overlay performance sk.d resistance tire/pavement noise

Aldehyde oxidase mediated enantioselective metabolic health risk.of dinotefuran

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Science China Chemistry 2024年第6期67卷 2079-2091页

作者： Liwei xu Xinxin xu Hua k.ang Chuanlai xu Xiaoling Wu State k.y Laboratory of Food Science and Resources Jiangnan UniversityWuxi214122China International Joint Research Laboratory for Biointerface and Biodetection and School of Food Science and Technology Jiangnan UniversityWuxi214122China Collaborative Innovation center of Food Safety and Quality Control in Jiangsu Province Jiangnan UniversityWuxi214122China

Chiral pollutants often pose significant differential environmental health *** this study,the biotransformation of chiral dinotefuran(DIN)and its enantioselective metabolic toxicity mechanisms have been systemically ***,reversedphase chromatography-high resolution mass spectrometry was developed to quantify the content of DIN R/S chiral enantiomer with pg level sensitivity,revealing a lower elimination rate constant(k.(e))of S-DIN(0.730 h^(-1))than R-DIN(0.746 h^(-1)).Secondly,the interaction mechanism between DIN metabolism and important endogenous bioactive molecules,such as aldehyde oxidase(AOX)and neurotransmitters,was *** DIN nitro-group was converted into a guanidine group by the reducing site of nearby flavin adenine dinucleotide(FAD)in AOX with the preferred higher affinity of ***,the endogenous tryptophan(Trp)aldehyde metabolic intermediate,5-hydroxyindoleacetaldehyde(5-HIAL),provides a persistent electron donor for DIN reduction via the oxidation-catalyzed site in AOX,resulting in remark.ble up-regulation of monoamine neurotransmitters such as serotonin and ***,the higher level of neurotransmitters further mediated dysregulation of oxylipin homeostasis via the serotonergic pathway,where S-DIN exhibited more pronounced liver lipid damage and environmental health risk.with the accumulated lipid biomark.rs,oxidized triglyceride(OxTG)and oxidized sphingomyelin(OxSM).This study elucidates the AOX-mediated enantioselectivity metabolic pathway of DIN,providing a new analytical method for chiral pollutants and paves the way for their health risk.assessments.

关键词： neonicotinoid dinotefuran enantiomer aldehyde oxidase metabolomics health risk

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Sk.letal interoception in osteoarthritis

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Bone Research 2024年第2期12卷 241-254页

作者： Dinglong Yang Jiawen xu k. xu Peng xu Department of Joint Surgery Honghui HospitalXi’an Jiaotong UniversityXi’an 710054China Department of Orthopedic Surgery and Orthopedic Research Institute West China HospitalSichuan UniversityChengdu 610041China

The interoception maintains proper physiological conditions and metabolic homeostasis by releasing regulatory signals after perceving changes in the internal state of the *** its various forms,sk.letal interoception specifically regulates the metabolic homeostasis of ***(OA)is a complex joint disorder involving cartilage,subchondral bone,and *** subchondral bone undergoes continuous remodeling to adapt to dynamic joint *** findings highlight that sk.letal interoception mediated by aberrant mechanical loads contributes to pathological remodeling of the subchondral bone,resulting in subchondral bone sclerosis in *** sk.letal interoception is also a potential mechanism for chronic synovial inflammation in *** this review,we offer a general overview of interoception,specifically sk.letal interoception,subchondral bone microenviroment and the aberrant subchondral *** also discuss the role of sk.letal interoception in abnormal subchondral bone remodeling and synovial inflammation in OA,as well as the potential prospects and challenges in exploring novel OA therapies that target sk.letal interoception.

关键词： homeostasis inflammation releasing

Malware Evasion Attack. Against IoT and Other Devices: An Empirical Study

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Tsinghua Science and Technology 2024年第1期29卷 127-142页

作者： Yan xu Deqiang Li Qianmu Li Shouhuai xu School of Computer Science and Engineering Nanjing University of Science and TechnologyNanjing 210094China School of Computer Science Nanjing University of Posts and TelecommunicationsNanjing 210023China Department of Computer Science University of Colorado Colorado SpringsColorado SpringsCO 80918USA

The Internet of Things(loT)has grown rapidly due to artificial intelligence driven edge *** enabling many new functions,edge computing devices expand the vulnerability surface and have become the target of malware ***,attack.rs have used advanced techniques to evade defenses by transforming their malware into functionality-preserving *** systematically analyze such evasion attack. and conduct a large-scale empirical study in this paper to evaluate their impact on *** specifically,we focus on two forms of evasion attack.:obfuscation and adversarial *** the best of our k.owledge,this paper is the first to investigate and contrast the two families of evasion attack. *** apply 10 obfuscation attack. and 9 adversarial attack. to 2870 malware *** obtained findings are as follows.(1)Commercial Off-The-Shelf(COTS)malware detectors are vulnerable to evasion attack..(2)Adversarial attack. affect COTS malware detectors slightly more effectively than obfuscated malware examples.(3)Code similarity detection approaches can be affected by obfuscated examples and are barely affected by adversarial attack..(4)These attack. can preserve the functionality of original malware examples.

关键词： Android malware obfuscation adversarial examples

The first mitogenome of Lauraceae(Cinnamomum chek.angense)

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Plant Diversity 2024年第1期46卷 144-148页

作者： Changwei Bi Ning Sun Fuchuan Han k.wang xu Yong Yang David k.Ferguson State k.y Laboratory of Tree Genetics and Breeding Co-Innovation Center for Sustainable Forestry in Southern ChinaKey Laboratory of Tree Genetics and Biotechnology of Educational Department of ChinaKey Laboratory of Tree Genetics and Silvicultural Sciences of Jiangsu ProvinceNanjing Forestry UniversityNanjing 210037China College of Information Science and Technology Nanjing Forestry UniversityNanjing 210037China Research Institute of Subtropical Forestry Chinese Academy of ForestryHangzhou 311400China Co-Innovation Center for Sustainable Forestry in Southern China College of Life SciencesNanjing Forestry UniversityNanjing 210037China Department of Paleontology University of ViennaViennaAustria

There are three distinct genetic systems in higher plants,the dominant nuclear genome and the semi-autonomous organelle genomes(plastids and mitochondria).In contrast to the conserved plastid genome(plastome),the plant mitochondrial genome(mitogenome)is characterized by an intriguing“evolutionary paradox”distinguished by a remark.bly low mutation rate but with a significantly high rearrangement rate(Palmer and Herbon,1988;Lai et al.,2022).

关键词： autonomous distinguished Palmer

Granting strength to aerogel fibers through encapsulation

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Science China Materials 2024年第4期67卷 1365-1366页

作者： Wenhui xu Department of Basic Chemistry School of PharmacyJiangxi University of Chinese MedicineNanchang 330004China

Aerogel fibers, distinguished by their lightweight nature, pronounced porosity, large surface area, and superior thermal insulation properties, have diversified applications in thermal management, energy devices, and environmental remediation[1]. However, compared with monolithic ones, these fibershaped aerogels exhibit limited mechanical strength and resilience due to their one-dimensional small size.

关键词： strength fibers thermal

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