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Effect of Interfacial Microstructure on Mechanical and Tribological Properties of Cu/WS_(2) Self-Iubricating Composites Sintered by Spark Plasma Sintering

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Acta Metallurgica Sinica(English Letters) 2021年第7期34卷 913-924页

作者： Zhitao Yu Minghui Chen Qunchang wang xiaolan wang Fuhui wang Shenyang National Laboratory for Materials Science Northeastern UniversityShenyang 110819China Institute of Metal Research Chinese Academy of SciencesShenyang 110016China

In this study,Cu/WS_(2) self-lubricating composites are fabricated by spark plasma *** microstructure and its effect on mechanical and tribological properties are *** sintering temperature at 850℃promotes decomposition of WS_(2) and its following interfacial reaction with Cu to form Cu_(0.4)W_(0.6) nanoparticles and Cu_(2)S,enhancing mechanical properties as well as wear resistance of the *** the destruction of WS_(2) leads to a high friction *** the contrary,for the composites sintered at 750℃,a nanoscale diffusion zone forms at the Cu/WS_(2) ***_(2) lubricant retains its lamellar *** composite shows excellent self-lubrication performance,with a low friction coefficient of ***,its mechanical properties are low,and the wear rate is one magnitude higher.

关键词： Self-lubricating composites Interfacial microstructure Wear Fracture

Multiscale prediction of wind speed and output power for the wind farm

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控制理论与应用（英文版） 2012年第2期10卷 251-258页

作者： xiaolan wang Hui LI School ofElectrical and Information Engineering Lanzhou University ofTechnologyLanzhou Gansu 730050China Key Laboratory of Gansu Advanced Control for Industrial Processes Lanzhou Gansu 730050China

This paper focuses on establishing the multiscale prediction models for wind speed and power in wind farm by the average wind speed collected from the history records. Each type of the models is built with different time scales and by different approaches. There are three types of them that a short-term model for a day ahead is based on the least squares support vector machine （LSSVM）, a medium-term model for a month ahead is on the combination of LSSVM and wavelet transform （WT）, and a long-term model for a year ahead is on the empirical mode decomposition （EMD） and recursive least square （RLS） approaches. The simulation studies show that the average value of the mean absolute percentage error （MAPE） is 4.91%, 6.57% and 16.25% for the short-term, the medium-term and the long-term prediction, respectively. The predicted data also can be used to calculate the predictive values of output power for the wind farm in different time scales, combined with the generator＇s power characteristic, meteorologic factors and unit efficiency under various operating conditions.

关键词： Multiscale prediction Wind power Least square support vector machine Wavelet transform Empiricalmode decomposition Recursive least square

Influence of Sputtered Nanocrystalline Coating on Oxidation and Hot Corrosion of a Nickel-based Superalloy M951

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Journal of Materials Science & Technology 2014年第9期30卷 867-877页

作者： Xinyue wang Li Xin Fuhui wang Shenglong Zhu Hua Wei xiaolan wang School of Materials and Metallurgy Northeastern University State Key Laboratory for Corrosion and Protection Institute of Metal ResearchChinese Academy of Sciences

The isothermal and cyclic oxidation behaviors in air and hot corrosion behaviors in Na2SO4 ＋ 25 wt% K2SO4 salt of M951 cast superalloy and a sputtered nanocrystalline coating of the same material were studied. Scanning electron microscopy, energy dispersive X-ray spectroscope, X-ray diffraction, and transmission electron microscopy were employed to examine the morphologies and phase composition of the M951 alloy and nanocrystalline coating before and after oxidation and hot corrosion. The as-sputtered nanocrystalline layer has a homogeneous y phase structure of very fine grain size （30-200 nm） with the preferential growth texture of （111） parallel to the interface. Adherent AI203 rich oxide scale formed on the cast M951 alloy and its sputtered coating after isothermal oxidation at 900 and 1000 ℃. However, when being isothermal oxidized at 1100℃ and cyclic oxidized at 1000 ℃, the oxide scale formed on the cast alloy was a mixture of NiO, NiAl2O4, Al2O3 and Nb205 and spalled seriously, while that formed on the sputtered coating mainly consisted of Al2O3 and was very adherent. Nanocrystallization promoted rapid formation of Al2O3 scale during the early stage of oxidation and enhanced the adhesion of the oxide scale, thus improved the oxidation resistance of the substrate alloy. Serious corrosion occurred for the cast alloy. The sputtered nanocrystalline coating apparently improved the hot corrosion resistance of the cast alloy in the mixed sulfate by the formation of a continuous Al2O3 and Cr2O3 mixed oxide layer on the surface of the coating, and the pre- oxidation treatment of the coating led to an even better effect.

关键词： M951 alloy Sputtered nanocrystalline coating Oxidation Corrosion Pre-oxidation

Calcinated Activated Carbon/MgFe-Layered Double Hydroxides for Enhanced Adsorption of Methyl Orange

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Wuhan University Journal of Natural Sciences 2021年第3期26卷 261-268页

作者： WU Yongjuan wang xiaolan LIU Bo School of Chemistry&Chemical Engineering Shaanxi Xueqian Normal UniversityXi’an 710100ShaanxiChina Safe College Xi’an University of Science and TechnologyXi’an 710054ShaanxiChina

Series of activated carbon(AC)modified MgFe-layered double hydroxides(LDH/ACs)were synthesized using ultrasonic-assisted co-precipitation *** the mass ratio of Mg/Fe-LDH and AC was varied at 1.55,2.34,and 2.86,*** calcinations of corresponding LDH/ACs were obtained at 723 K for 5 h and named as LDO-AC-1.55,LDO-AC-2.34 and LDO-AC-2.86,*** products were characterized by Fourier transform infrared spectroscopy(FT-IR),X-ray diffraction(XRD),Brunauer-Emmett-Teller(BET)measurements and scanning electron microscopy(SEM).LDO-ACs were applied for the removal of methyl orange(MO).The result showed that aggregation degree of MgFe-LDH decreased in the existence of *** pore sizes of LDO-AC-1.55,LDO-AC-2.34 and LDO-AC-2.86 markedly increased with the sharp decreasing of surface *** values of the statured adsorption capacity of LDO-AC-1.55,LDO-AC-2.34 and LDO-AC-2.86 were obviously higher than those of MgFe-layered double hydroxides fabricated by traditional method(LDO0).The mechanism for the enhanced adsorption may be that the loose macrospore structure of LDO-AC-1.55,LDO-AC-2.34 and LDO-AC-2.86 abbreviates the diffusion resistance and bore repulsive force of MO molecular coupled with its space confinement effect in contrast with LDO0,which is favor for the free self-assembly of MO to form intercalation ***-loaded LDO-AC-2.34 was regenerated by calcination and reused several times,still retaining its original adsorption capacity.

关键词： activated carbon MgFe-layered double hydroxides adsorption mechanism

Assessment of the Ecological Security in the Three Gorges Reservoir Area by Using the Ecological Footprint Method

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Journal of Mountain Science 2012年第6期9卷 891-900页

作者： wang Haiming wang Hai'e SUN Hongyang wang xiaolan LIAO Xiaoyong CHEN Zhijian LI Xianwei Institute of Mountain Hazards and Environment Chinese Academy of SciencesChengdu 610041China Sichuan Academy of Agricultural Sciences Chengdu 610066China Sichuan Agricultural University Ya'an 626014China

The ecological footprint concept and its calculation models are useful for the measurement of the sustainable level of social and economic *** ecological security situation of the Three Gorges Reservoir Area(TGRA) was evaluated using this concept in this *** construction of the Three Gorges Reservoir has led to the change in the ecology and immigration status of *** ecological footprint method is an important means to study the regional ecological *** results suggested that,by excluding the areas for biodiversity conservation(12% of the total land),the ecological footprint per capita was 0.57895 ha,which exceeded the ecological carrying capacity in *** total ecological deficit was found to be 11,522,193.34 ha,accounting for 95.02% of the ecological carrying *** findings suggested that the ecological security of TGRA was not *** order to compensate for the ecological deficit,it was essential to introduce natural resources from other regions.

关键词： Three Gorges Reservoir Area(TGRA) Ecological footprint Ecological security

Effect of Amino-,Methyl- and Epoxy-Silane Coupling as a Molecular Bridge for Formatting a Biomimetic Hydroxyapatite Coating on Titanium by Electrochemical Deposition

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Journal of Materials Science & Technology 2016年第9期32卷 956-965页

作者： Guoxin Tan Kongyou Ouyang Hang wang Lei Zhou xiaolan wang Yan Liu Lan Zhang Chengyun Ning School of Chemical Engineering and Light Industry Guangdong University of Technology College of Materials Science and Technology South China University of Technology State Key Laboratory for Mechanical Behavior of Materials Xi'an Jiaotong University

The objective of this study was to determine the role of functional groups of silane coupling on bioactive titanium （Ti） surface by electrochemical deposition, and calcium phosphate （CAP） coating, as well as bone cell adhesion and proliferation. Methyl group （-CH3）, amino group （-NH2）, and epoxy group （-glyph name--C（O）C） were introduced onto the bioactive Ti surface using self-assembled monolayers （SAMs） with different silane coupling agents as molecular bridges. The effect of the surface functional groups on the growth features of the CaP crystals was analyzed （including chemical compositions, element content, minerals morphology and crystal structure etc.）. CH3-terminated SAMs showed a hydrophobic surface and others were hydrophilic by contact angle measurement; NH2-terminated SAMs showed a positive charge and others were negatively charged using zeta-potential measurement. Scanning electron microscopy results confirmed that flower-like structure coatings consisting of various pinpoint-like crystals were formatted by different functional groups of silane coupling, and the CaP coatings were multicrystalline consisting of hydroxyapatite （HA） and precursors. CaP coating of CH3-terminated SAMs exhibited more excellent crystallization property as compared to coatings of --NH2 and -C（O）C groups. In vitro MC3T3- El cells adhesion and proliferation were performed. The results showed that CaP coatings on silane coupling functionalized surfaces supported cell adhesion and proliferation. Thus, these functional groups of silane coupling on Ti can form homogeneous and oriented nano-CaP coatings and provide a more biocompatible surface for bone regeneration and biomedical applications.

关键词： Silane coupling Molecular bridge Calcium phosphate coatings Titanium Electrochemical deposition

Cloning and characterization of rice RH3 gene induced by brown planthopper

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Chinese Science Bulletin 2003年第18期48卷 1976-1981页

作者： xiaolan wang Qingmei Weng Aiqing You Lili Zhu Guangcun He Wuhan Univ Key Lab Minist Educ Plant Dev Biol Coll Life Sci Wuhan 430072 Peoples R China

Experiments have showed that the histone H3 gene is correlated with development, cell speciality and stress response. The RH3 full-length cDNA was isolated from the cDNA library of rice infested by brown planthopper (BPH) with EST (Accession no. BU572343) screened from rice SSH library as probe. This gene encodes histone H3 protein in-cluding 136 amino acids, with one amino acid different from a kind of disease resistance-related protein in rice (AF467728). At the position 126, the aspartic acid is replaced by lysine. The time course results showed that the expression of the RH3 began to increase at 8 h after BPH-feeding, and got to its peak at 96 h. Regulations of the gene expression in treatments with stress/defense signal molecules were ana-lyzed by Northern blot. Water deficit and Pyricularia grisea increased the expression of RH3 while ABA down-regulated the gene. The enhanced accumulation of RH3 transcripts in the vascular bundle and short cell of stem after BPH feeding was revealed by RNA in situ hybridization. It is the first time to report that RH3 is correlated with the response of rice to BPH.

关键词： brown planthopper histone H3 RNA in situ hybridiza-tion defense response.

Effects of Different Organic Residues on Rice Yield and Soil Quality

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Journal of Mountain Science 2012年第5期9卷 715-722页

作者： PENG Li LIU Wei SU Chunjiang LI Ping FANG Yan wang xiaolan SUN Lian Institute of Mountain Hazards and Environment Chinese Academy of SciencesNo.9.Section 4South Renmin RoadChina Graduate University of Chinese Academy of Sciences Beijing 100049China Institute of Horticulture Sichuan Academy of Agricultural SciencesChengdu 610066China Key Laboratory of Horticultural Crops Biology and Germplasm Enhancement in Southwest Regions Ministry of AgricultureChengdu 61oo66China Southwest Jiaotong University Chengdu 610031China Sichuan Technology and Business Collage Dujiangyan 611844China Sichuan Provincial Environmental Information Center Chengdu 610015China

Calcaric regosols are a valuable land resource, distributed widely across western China. Soil quality has deteriorated considerably in recent years owing to the blind pursuit of economic benefits. A 2-year field experiment was carried out to evaluate the effects of using spent mushroom compost, leguminous plant (Vicia sepium L.) compost, and a combination of the two (at a 1:1 and 2:1 ratio), on rice yield and soil quality in a suburb of China. Vicia sepium L. composted with spent mushroom compost at a 1:1 ratio produced the highest grain and stover yield, grain and stover phosphorus concentration, and phosphorus uptake of rice; they were 56.5%, 93.2%, 89.3%, 198.6% and 22.2% greater than control soil, respectively. The 2:1 ratio (Vicia sepium L.: spent mushroom compost) produced the highest grain N concentration, stover N concentration, and N uptake; they were 31.6%, 31.4%, and 40.7% higher than control, respectively. Soil physical, chemical, and environmental properties were improved with the application of Vicia sepium L. composted with spent mushroom compost at a 2:1 ratio. In particular, soil water-stable aggregates, organic carbon, particulate organic carbon, total nitrogen, available potassium, and cation exchange capacity increased, whereas bulk density, pH, and phytoavailable heavy metals decreased. This organic treatment is beneficial to improve soil quality indicators, and contribute to soil restoration.

关键词： Co-composting Leguminous plants Soilquality indicators Soil restoration Spent mushroomcompost

Analysis of the effect of PCR testing and antigen testing on controlling the transmission for Omicron based on different scenarios

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Infectious Disease Modelling 2023年第4期8卷 939-946页

作者： Wentao Song Buasiyamu Abudunaibi Zeyu Zhao Weikang Liu xiaolan wang Tianmu Chen State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics School of Public HealthXiamen UniversityXiamen CityFujian ProvincePeople's Republic of China Shangrao Center for Disease Control and Prevention Shangrao CityJiangxi ProvincePeople's Republic of China

After the policy adjustment,China no longer carries out COVID-19 PCR testing for all people,and antigen testing has become the main way to detect and manage infectious *** developed a dynamic model to evaluate and compare the effects between PCR and antigen testing for controlling the *** to the increase of contact degree,the peak reduction effect of PCR testing in population is lower than that of antigen *** if it was only 20%of people isolated at home after antigen testing,the peak of the epidemic could be reduced by 9.46%.If the proportion of antigen testing is further increased to 80%,the peak of the pandemic can be reduced by 31.41%.Antigen testing performed better effects in school(reduction proportion 29.27%)and community(29.34%)than in workplace(27.75%).Therefore,we recommend that antigen testing in the popu-lation should be encouraged during the pandemic,and home isolation of infected persons should be advocated,especially in crowded *** improve the availability of antigen,the testing proportion should be further enhanced.

关键词： PCR testing Antigen testing COVID-19