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Effects of Al8Cu4Er Phase on Corrosion Behavior of Al-Cu-Mg alloy with Er addition

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Acta Metallurgica Sinica(English Letters) 2020年第10期33卷 1379-1387页

作者： wei-ning Shi Hai-Fei Zhou Xin-Fang Zhang State Key Laboratory of Advanced Metallurgy School of Metallurgical and Ecological EngineeringUniversity of Science and Technology BeijingBeijing 100083China Zhejiang Electric Power Corporation Research Institute Hangzhou 310014China

The effect of Al8Cu4Er phase on the corrosion behavior of Al-Cu-Mg alloy with rare earth Er addition in an under-aging state was *** results revealed that the addition Er into the Al-Cu-Mg alloy induced the formation of Al8Cu4 Er *** Al8Cu4Er phase can significantly refine the grains during recrystallization,thereby suppressing the continuous precipitation of S-phase at grain boundaries and improving the resistance to intergranular ***,the corrosion susceptibility of local regions around the Al8Cu4Er phase with large dimension was higher than that of the AlCuFeMnSi phase,but weaker than that of θ phase,resulting in decreased pitting corrosion resistance.

关键词： Aluminum alloy Er micro-alloying Corrosion Grain boundaries Secondary phase

Selective Insertion in Copolymerization of Ethylene and Styrene Catalyzed by Half-Titanocene System Bearing Ketimide Ligand： A Theoretical Study

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Chinese Journal of Chemistry 2017年第11期35卷 1731-1738页

作者： Xiaowei Xu Gaohong He ning-ning wei Ce Hao Yu Pan State Key Laboratory of Fine Chemicals School of Petroleum and Chemical Engineering Dalian University of Technology Panjin Liaoning 124221 China School of Life Science and Medicine Dalian University of Technology Panjin Liaoning 124221 China

The copolymerization of ethylene and styrene can be efficiently carried out by using Cp＊TiCl2（N=CtBu2）/ MAO （Cp＊=η5-C5Me5） system, yielding the poly（ethylene-co-styrene）s with isolated styrene units. In order to in- vestigate the reasons for formation of the structure, the mechanism of copolymerization, especially the selective in- sertion of ethylene and styrene, is studied in detail by density functional theory （DFT） method. At the initiation stage, insertion of ethylene is kinetically more favorable than insertion of styrene, and insertion of styrene kinet- ically and thermodynamically prefers 2,1-insertion. That is different from the conventional half-titanocene system, in which the 1,2-insertion is favorable. At chain propagation stage, the computational results suggest that the con- tinuous insertion of styrene is hard to occur at room temperature due to the high free energy barriers （28.90 and 35.04 kcal/mol for 1,2-insertion, and 29.15 and 34.00 kcal/mol for 2,1-insertion） and thermodynamically unfavora- ble factors in two different conditions. That is mainly attributed to the steric hindrance between the coming styrene and chain-end styrene or ketimide ligand. The computational results are in good agreement with the experimental data.

关键词： polymerization mechanism density functional theory (DFT) half-tianocene copolymerization selec-tive insertion

Effect of the Cylindrical Interface Properties on Ultrasonic Transverse Wave Scattering

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Chinese Physics Letters 1994年第4期11卷 211-214页

作者： WANG Yaojun OU Xianhua ning wei Institute of Acoustics Nanjing UniversityNanjing 210008

A simplified model for ultrasonic transverse wave scattering in cylindrically layered composite with thin interface layers is *** ultrasonic transverse wave attenuation due to the scattering in a fiber reinforced composite is found to be greatly affected by the properties of the interface layers which are simulated as viscoelastic media.

关键词： composite interface transverse

Interactions of Phenanthroline Compounds with i-Motif DNA

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Chemical Research in Chinese Universities 2014年第3期30卷 495-499页

作者： GAO ning WANG Yanbo wei Chunying Key Laboratory of Chemical Biology and Molecular Engineering of Ministry of Education Institute of Molecular Science Shanxi University Taiyuan 030006 P. R. China

The interactions of each of three phenanthroline derivatives 1, 2 and 3 with the human telomeric/-motif DNA were investigated. The results suggest these compounds are potent binders. The compounds could stabilize the structure of i-motif DNA by π-π stacking. Moreover, the binding constants of the compounds with/-motif DNA were （2.71-8.12）×10^4 L·mol^-1, and the binding stoichiometry ratio was 1：1. CD studies reveal that the binding by phenanthroline comoounds perturbs the conformation of i-motif DNA.

关键词： i-Motif DNA Phenanthroline derivative Interaction

The energy-environment nexus:aerosol science and technology enabling solutions

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Frontiers of Environmental Science & Engineering 2011年第3期5卷 299-312页

作者： Pratim BISWAS wei-ning WANG Woo-Jin AN Aerosol and Air Quality Research Laboratory Department of EnergyEnvironmental and Chemical EngineeringWashington University in St.LouisSt.LouisMO 63130USA

Energy issues are important and consumption is slated to increase across the globe in the *** energy-environment nexus is very important as strategies to meet future energy demand are *** ensure sustainable growth and development,it is essential that energy production is environmentally *** are two temporal issues—one that is immediate,and needs to address the environmental compliance of energy generation from fossil fuel sources;and second that is the need to develop newer alternate and more sustainable approaches in the *** science and technology is an enabling discipline that addresses the energy issue over both these time *** paper is a review of aspects of aerosol science and engineering that helps address carbon neutrality of fossil *** materials to meet these challenges are *** approaches to effective harvesting of sunlight that are enabled by aerosol studies are discussed.

关键词： energy-environment nexus aerosol science and technology fossil fuels carbon dioxide conversion solar energy nanoparticle technology

Feeding of pea leafminer larvae simultaneously activates jasmonic and salicylic acid pathways in plants to release a terpenoid for indirect defense

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Insect Science 2021年第3期28卷 811-824页

作者： Jun-Nan Yang Jia-ning wei Le Kang State Key Laboratory of Integrated Management of Pest Insects and Rodents Institute of ZoologyChinese Academy of SciencesBeijingChina CAS Center for Excellence in Biotic Interactions University of Chinese Academy of SciencesBeijingChina

The pea leafminer,Liriomyza huidobrensis,is an important pest species affecting ornamental crops *** damage consists of oviposition and feeding punctures created by female adult flies as well as larva-bored mines in leaf mesophyll *** plants indirectly defend themselves from these two types of leafminer damage has not been sufficiently *** this study,we compared the indirect defense responses of bean plants infested by either female adults or *** of leaves by adults released green leaf volatiles and terpenoids,while larval feeding caused plants to additionally emit methyl salicylate and(E,E)-4,8,12-trimethyl-1,3,7,11-tridecatetraene(TMTT).Puncturing of plants by female adults induced increases in jasmonic acid(JA)and JA-related gene expressions but reduced the expressions of salicylic acid(SA)-related *** contrast,JA and SA and their-related gene expression levels were increased significantly by larval *** exogenous application of JA+SA significantly triggered TMTT emission,thereby significantly inducing the orientation behavior of *** study has confirmed that larval feeding can trigger TMTT emission through the activation of both JA and SA pathways to attract parasitoids;however,TMTT alone is less attractive than the complete blend of volatiles released by infested plants.

关键词： jasmonic acid Liriomyza huidobrensis parasitoids salicylic acid TMTT

Safety lifetime analysis method for multi-mode time-dependent structural system

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Chinese Journal of Aeronautics 2022年第11期35卷 294-308页

作者： Yingshi HU Zhenzhou LU ning wei Xia JIANG Changcong ZHOU School of Aeronautics Northwestern Polytechnical UniversityXi'an 710072China

It is important to determine the safety lifetime of Multi-mode Time-Dependent Structural System(MTDSS). However, there is still a lack of corresponding analysis ***, this paper establishes MTDSS safety lifetime model firstly, and then proposes a Kriging surrogate model based method to estimate safety lifetime. The first step of proposed method is to construct the Kriging model of MTDSS performance function by using extremum learning function. By identifying possible extremum mode of MTDSS, the performance function of MTDSS can be equivalently transformed into the one of Single-mode Time-Dependent Structure(STDS).The second step is to use the Advanced First Failure Instant Learning Function(AFFILF) to train the Kriging model constructed in the first step, so that the convergent Kriging model can identify the possible First Failure Instant(FFI) of STDS. Then safety lifetime can be searched quickly by dichotomy search. By using AFFILF, the minimum instant that the state is not accurately identified by the current Kriging model is selected as the training point, which avoids the unnecessary calculation which may be introduced into the existing First Failure Instant Learning Function(FFILF).In addition, the Candidate Sample Pool(CSP) reduction strategy is also adopted. By adaptively deleting the random candidate sample points whose FFI have been accurately identified by the current Kriging model, the training efficiency is further improved. Three cases show that the proposed method is accurate and efficient.

关键词： Kriging Learning function Lifetime System reliability Time-dependent reliability analysis

Theoretical assessment of the Ca^2＋ oscillations in the afferent arteriole smooth muscle cell of the rat kidney

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International Journal of Biomathematics 2018年第3期11卷 267-287页

作者： ning wei Anita T. Layton Department of Mathematics Duke University Durham NC USA

The afferent arteriole （AA） of rat kidney exhibits the myogenic response, in which the vessel constricts in response to an elevation in blood pressure and dilates in response to a pressure reduction. Additionally, the AA exhibits spontaneous oscillations in vascular tone at physiological luminal pressures. These time-periodic oscillations stem from the dynamic exchange of Ca^2＋ between the cytosol and the sarcoplasmie reticulum, cou- pled to the stimulation of Ca^2＋-activated potassium and chloride channels, and to the modulation of voltage-gated L-type Ca^2＋ channels. The effects of physiological factors, including blood pressure and vasoactive substances, on AA vasomotion remain to be well characterized. In this paper, we analyze a mathematical model of Ca^2＋ signaling in an AA smooth muscle cell. The model represents detailed transmembrane ionic trans- port, intracellular Ca^2＋ dynamics as well as kinetics of nitric oxide （NO） and superoxide （O2^-） formation, diffusion and reaction. NO is an important factor in the maintenance of blood pressure and O2^- has been shown to contribute significantly to the functional alternations of blood vessels in hypertension. We perform a bifurcation analysis of the model equations to assess the effect of luminal pressure, NO and O2^- on the behaviors of limit cycle oscillations.

关键词： Afferent arteriole limit cycle oscillation bifurcation analysis nitric oxide superoxide.

Molecular and functional characterization of three odorant-binding proteins from the wheat blossom midge,Sitodiplosis mosellana

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Insect Science 2020年第4期27卷 721-734页

作者： wei-ning Cheng Yu-Dong Zhang wei Liu Guang-wei Li Keyan Zhu-Salzman Key Laboratory of Integrated Pest Management on Crops in Northwestern Loess Plateau Ministry of AgricultureNorthwest A&F UniversityYang lingShaanxiChina Shaanxi Key Laboratory of Chinese Jujube Van'an UniversityVan'anShaanxiChina Department of Entomology Texas A&M UniversityCollege StationTXUSA

Sitodiplosis mosellana,a periodic but devastating wheat pest,relies on wheat spike volatiles as a cue in sclecing hosts for *** odorant-binding proteins(OBPs)are thought to play essential roles in filtering,binding and transporting hydropho-bic odorant molecules to specific *** date,the molecular mechanisms underlying *** olfaction are poorly ***,three *** antenna-specific OBP genes,SmosOBPII,16 and 21,were cloned and bacterially *** properties of the recombinant proteins to 28 volatiles emitted from wheat spikes were in-vestigated using fluorescence competitive binding *** analysis suggested that these SmosOBPs belong to the Classic OBP ***-binding analysis showed that all three SmosOBPs preferentially bound alcohol,ester and ketone com-pounds,and SmosOBP11 and 16 also selectively bound terpenoid *** par-ticular,the three SmosOBPs had high binding affinities(Ki<20μmol/L)to 3-hexanol and cis-3-hexenylacetate that elicited strong electroantennogram(EAG)response fromfemale *** addition,SmosOBP11 displayed significantly higher binding(Ki<8μmo/L)than SmosOBP16 and 21 to l-octen-3-ol,D-panthenol,a-pinene and heptyl acetate which elicited significant EAG response,suggesting that SmosOBP11 plays a ma-jor role in recognition and transportation of these *** findings have provided important insight into the molecular mechanism by which *** specifically rec-ognizes plant volatiles for host selection,and have facilitated identification of effective volatile attractants that are potentially useful for pest monitoring and trapping.

关键词： binding assay electroantennogram response host selection odorant-binding protein Sitodiplosis mosellana wheat spike violates