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Uncover the mystery of interfacial interactions in immiscible composites by spectroscopic microscopy:A case study with W-Cu

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Journal of Materials Science & Technology 2022年第31期126卷 106-115页

作者： Zhi Zhao Fawei Tang Chao Hou Xintao Huang Xiaoyan Song Faculty of Materials and Manufacturing Key Laboratory of Advanced Functional MaterialsEducation Ministry of ChinaBeijing University of TechnologyBeijing 100124China

Characterizing immiscible metallic composites with electron microscopy and X-ray spectroscopy is the classic way of obtaining their structural and physical details.Nevertheless,such a combination lacks abil-ity to tell the interfacial interactions at grain boundaries.Here we demonstrate a novel strategy to un-cover the mystery of interfacial interactions in such systems by spectroscopic microscopy.The morpho-logical and spectral data of samples were simultaneously recorded and analyzed,which reveals critical information regarding interfacial electronic modes.Taking W-Cu as a model,we experimentally quanti-fied its connectivity and unambiguously identified conditional bonding between W and Cu.Further,we chemically reconstructed the specific W-Cu boundary that possessed the strongest interactions and inves-tigated its atomic structure.The mechanism of W-Cu bonding was proposed and verified by first-principle calculations.The above methodology holds great promise to serve as a universal approach in achieving in-depth understanding of immiscible composites.

关键词： Metal-matrix composites Interface Physical properties Spectroscopic microscopy Interfacial bonding

Effect of Microstructure Scale on Negative Thermal Expansion of Antiperovskite Manganese Nitride

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Journal of Materials Science & Technology 2014年第9期30卷 903-909页

作者： Zhonghua Sun Xiaoyan Song College of Materials Science and Engineering Key Laboratory of Advanced Functional MaterialsEducation Ministry of China Beijing University of Technology Hebei Iron and Steel Technology Research Institute

The negative thermal expansion （NTE） properties of the antiperovskite manganese nitrides with micron-scale, submicron-scale and nanometer-scale microstructures, respectively, were investigated using the Mn3Cu0.5Ge0.5N composition as an example. It was discovered that the NTE start temperature, NTE operation temperature range and coefficient of NTE change obviously in a wide range with decreasing the grain size level of the microstructure. The mechanisms for the broadening of the NTE operation temperature range and the decrease in the absolute value of NTE coefficient were proposed based on the grain-size-dependence of the frustrated magnetic interactions and magnetic ordering. The present study indicates that the NTE properties of the antiperovskite manganese nitrides can be tailored by the control of the microstructure scale.

关键词： Negative thermal expansion Antiperovskite manganese nitride Magnetic interaction Microstructure scale

Fine particle trace elements at a mountain site in southern China:Source identification,transport,and health risks

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Journal of Environmental Sciences 2024年第7期141卷 166-181页

作者： Jiaoping Xing Runping Ding Feifeng Chen Linyu Peng Wenhua Wang Xiaoyan Song Qing Ye Yuanqiu Liu Key Laboratory of State Forestry and Grassland Administration on Forest Ecosystem Protection and Restoration of Poyang Lake Watershed School of ForestryJiangxi Agricultural UniversityNanchang 330045China School of Resources and Materials Northeastern University at QinhuangdaoQinhuangdao 066004China College of Geosciences and Engineering North China University of Water Resources&Electric PowerZhengzhou 450046China

Trace elements in atmospheric particulate matter play a significant role in air quality,human health,and biogeochemical cycles.In this study,the trace elements(Ca,Al,K,Fe,Na,Mg,Zn,Pb,Mn,Ti,Cu,Cr,Sr,Ni)in PM2.5samples collected at the summit of Mt.Lushan were analyzed to quantify their abundance,source,transport,and health risks.During the whole sampling period,the major trace elements was Ca,Al,and K.While the trace metals with the lowest concentrations were Sr,Ni,Rb,and Cd.The trace elements were influenced by air mass transport routes,exhibiting an increasing trend of crustal elements in the northwesterly airmass and anthropogenic elements(Zn,Mn,Cu,and Ni)in the easterly air masses.Construction dust,coal+biomass burning,vehicle emission,urban nitrate-rich+urban waste incineration emissions,and soil dust+industry emissions were common sources of PM2.5on Mt.Lushan.Different air mass transport routes had various source contribution patterns.These results indicate that trace elements at Mt.Lushan are influenced by regional anthropogenic emissions and monsoon-dominated trace element transport.The total resulting cancer risk value that these elements posed were below the acceptable risk value of 1×10^(-6),while the non-carcinogenic risk value(1.72)was higher than the safety level,suggesting that non-carcinogenic effects due to these trace elements inhalation were likely to occur.Vehicle emission and coal+biomass burning were the common dominant sources of non-cancer risks posed by trace elements at Mt.Lushan.

关键词： Trace elements Risk assessment Cluster analysis Source apportionment

Comparative experiment on treating digested piggery wastewater with a biofilm MBR and conventional MBR： simultaneous removal of nitrogen and antibiotics

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Frontiers of Environmental Science & Engineering 2017年第2期11卷 123-131页

作者： Xiaoyan Song Rui Liu Lujun Chen Tomoki Kawagishi Zhejiang Provincial Key Laboratory of Water Science and Technology Department of Environment in Yangtze Delta Region Institute of Tsinghua University-Zhejiang Jiaxing 314006 China School of Environment Tsinghua University Beijing 100084 China Aqua Development Center Mitsubishi Rayon Co. Ltd. Toyohashi 4408601 Japan

A biofilm membrane bioreactor （BF-MBR） and a conventional membrane bioreactor （MBR） were parallelly operated for treating digested piggery wastewater. The removal performance of COD, TN, NH4＋-N, TP as well as antibiotics were simultaneously studied when the hydraulic retention time （HRT） was gradually shortened from 9 d to 1 d and when the ratio ofinfluent COD to TN was changed. The results showed that the effluent quality in both reactors was poor and unstable at an influent COD/ TN ratio of 1.0±0.2. The effluent quality was signifcantly improved as the influent COD/TN ratio was increased to 2.3±0.5. The averaged removal rates of COD, NH4＋-N, TN and TP were 92.1%, 97.1%, 35.6% and 54.2%, respectively, in the BF-MBR, significantly higher than the corresponding values of 91.7%, 90.9%, 17.4% and 31.9% in the MBR. Analysis of 11 typical veterinary antibiotics （from the tetracycline, sulfonamide, quinolone, and macrolide families） revealed that the BF-MBR removed more antibiotics than the MBR. Although the antibiotics removal decreased with a shortened HRT, high antibiotics removals of 86.8%, 80.2% and 45.3% were observed in the BF-MBR at HRT of 5~4 d, 3-2 d and 1 d, respectively, while the corresponding values were only 83.8%, 57.0% and 25.5% in the MBR. Moreover, the BF-MBR showed a 15% higher retention rate of antibiotics and consumed 40% less alkalinity than the MBR. Results above suggest that the BF-MBR was more suitable for digested piggery wastewater treatment.

关键词： AlkalinityAntibioticsBiofilmDigested piggery wastewater （DPW）Membrane bioreactor

Outstanding high-temperature oxidation-and wear-resistance of WC based cermets

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Journal of Materials Science & Technology 2023年第24期155卷 33-46页

作者： Wentao Jiang Hao Lu Xuemei Liu Haibin Wang Dongyang Li Chao Liu Mingsheng Wang Xiaoyan Song Faculty of Materials and Manufacturing Key Laboratory of Advanced Functional Materials Ministry of Education of China Beijing University of Technology Beijing 100124 China Department of Chemical & Materials Engineering University of Alberta Edmonton Alberta T6G 2H5 Canada Xiamen Tungsten Co. Ltd. Xiamen 361009 China

The interaction between oxidation and frictional load can greatly deteriorate the performance of ceramic-metal composites.In this work,we used WC-Co cermet as a representative of ceramic-metal composites to study its wear failure behavior and protection effectiveness.It is found that a transition of wear mechanism from mechanical wear to oxidative wear occurs with increasing temperature.The addition of zirconia can significantly improve the anti-oxidation performance and load-bearing capacity of the cermet under the frictional load.This is mainly attributed to the modulation of the tribo-oxide layer constitutions and changes in surface morphology.The zirconia component facilitates the formation of a dense protective oxide layer and reduces the content of brittle oxides on the worn surface.Based on the understanding of the temperature-and oxidation-induced compositional and microstructural evolutions at the sliding contact surface and subsurface,a promising approach is proposed for developing ceramic-metal composites with high wear resistance and anti-oxidation capability.

关键词： Cermet Anti-oxidation performance Wear mechanism Zirconia

Comparative study on microbial community in intermittently aerated sequencing batch reactors （SBR） and a traditional SBR treating digested piggery wastewater

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Frontiers of Environmental Science & Engineering 2017年第3期11卷 97-106页

作者： Xiaolin Sheng Rui Liu Xiaoyan Song Lujun Chen Kawagishi Tomoki Zhejiang Provincial Key Laboratory of Water Science and Technology Department of Environment in Yangtze Delta Region Institute of Tsinghua University Zhejiang Jiaxing 314006 China School of Environment Tsinghua University Beijing 100084 China Aqua Development Center Mitsubishi Rayon Co. Ltd. Toyohashi 4408601 Japan

A traditional sequencing batch reactor （SBR） and two intermittently aerated sequencing batch reactors （IASBRs） were parallelly operated for treating digested piggery wastewater. Their microbial communities were analyzed, and the nitrogen removal performance was compared during the long term run. IASBRs demonstrated higher removal rates of total nitrogen （TN） and ammonium nitrogen （NH4＋ -N） than the SBR, and also demonstrated higher resistance against TN shock load. It was found that the more switch times between aerobic/anoxic in an IASBR, the higher the removal rates of TN and NH4＋ N. All the reactors were predominated by Thauera, Nitrosomonas and Nitrobacter, which were considered to be species of denitrifiers, ammonium oxidizing bacteria （AOB） and nitrite oxidizing bacteria （NOB）, respectively. However, the abundance and diversity was of great difference. Compared with SBR, IASBRs achieved higher abundance of denitrification related bacteria. IASBR 1# with four aerobic/anoxic switch times was detected with 25.63% of Thauera, higher than that in IASBR 2# with two aerobic/anoxic switch times （l 1.57% of Thauera）, and much higher than that in the SBR （only 6.19% of Thauera）. IASBR 2# had the highest percentage of AOB, while 1ASBR 1# had the lowest percentage. The denitrifiers abundance was significantly positive correlated with the TN removal rate. However, the NH4＋ N removal rate showed no significant correlation with the AOB abundance, but might relate to the AOB activity which was influenced by the average free ammonium （FA） concentration. Nitrobacter was the only NOB genus detectable in all reactors, and were less than 0.03%.

关键词： Digested piggery wastewater Intermittent aeration aeration Microbial community Partial nitrification^lenitrification processSequencing batch reactor （SBR）

Changes and determining factors of crop evapotranspiration derived from satellite-based dual crop coefficients in North China Plain

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The Crop Journal 2022年第5期10卷 1496-1506页

作者： Qinghua Tan Yujie Liu Tao Pan Xianfang song xiaoyan Li Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China State Key Laboratory of Earth Surface Processes and Resource Ecology Faculty of Geographical ScienceBeijing Normal UniversityBeijing 100875China

Evaluating actual crop evapotranspiration(ET) variations and their determining factors under changing climates is crucial for agricultural irrigation management and crop productivity improvement in nonhumid regions.This study analyzed the spatiotemporal characteristics and detected the determining factors of ETfor winter wheat and summer maize rotation system from 2000 to 2017 in the North China Plain(NCP),by combining the FAO-56 dual crop coefficient approach with remotely sensed vegetation indices(VIs).The results indicated that daily air temperature increased in varying degrees while wind speed and sunshine hours decreased slightly during the growing season of winter wheat and summer maize over the study period.The trends of relative humidity and effective precipitation varied in crop growing seasons.Based on the validated relationship of dual crop coefficients and VIs,the estimated multi-year average ETof winter wheat(370.29±31.28 mm) was much higher than summer maize(281.85±20.14 mm),and the rotation cycle was 652.43±27.67 mm.Annual ETof winter wheat and the rotation cycle increased by 2.96 mm aand 1,77 mm a,respectively.However,the ETof summer maize decreased with distinct spatial variation.Spatially,winter wheat ETincreased significantly in the northeast NCP,covering the Beijing-Tianiin-Hebei areas.Meanwhile,significant increases in summer maize ETwere detected in the southwest NCP.The sensitivity and contribution analysis showed that ETof winter wheat and summer maize was positively sensitive to temperature,wind speed,and sunshine hours while negatively to relative humidity.Moreover,wind speed and sunshine hours contributed most to changes in ET(around 20%-40%).

关键词： Actual crop evapotranspiration Determining factor North China Plain Rotation system Spatiotemporal variation

Heat Storage/Heat Release of Phase-Change Filling Body with Casing Heat Exchanger for Extracting Geothermal Energy

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Journal of Thermal Science 2023年第3期32卷 1171-1189页

作者： ZHANG xiaoyan XU Muyan LIU Lang YANG Qixing KI-IL song Energy School Xi'an University of Science and TechnologyXi'an 710054China Key Laboratory of Western Mines and Hazards Prevention Ministry of Education of ChinaXi'an 710054China Department of Civil Engineering Inha UniversityIncheon 402-751South Korea

Arranging heat exchanger in filling body to extract geothermal energy is an effective way to alleviate the problems of high ground pressure and high ground temperature in deep resource exploitation.Filling body with casing heat exchanger was acted as research object,encapsulating phase change materials(PCMs)in annular space.During heat storage and heat release process,the effects of different PCMs on temperature distribution,phase-change process and heat transfer performance were studied.The result indicates:During heat storage process,the temperature increases rapidly and the melting process is accelerated for the position closer surrounding rock.CaCl_(2)·6H_(2)O/EG can make filling body complete heat storage process in the shortest time because of its good thermal diffusivity.The heat storage capacity of PCMs backfill is significantly higher than that of ordinary backfill;it increases by 36.6%-67.3%at heat storage of 10 h.During heat release process,the closer to the heat exchange tube,the greater the temperature drop in filling body.The maximum value of heat release rate and heat release capacity is in CaCl_(2)·6H_(2)O/EG backfill,it can release 116.4%more heat than RT35backfill after heat release of 12 h,the maximum value of effectiveness and its heat transfer rate also is in CaCl_(2)·6H_(2)O/EG backfill.This paper provides the basic data for the selection of PCMs in phase-change thermal storage filling body.

关键词： flling body heat exchanger phase change material heat storage/heat release

Advantages of intermittently aerated SBR over conventional SBR on nitrogen removal for the treatment of digested piggery wastewater

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Frontiers of Environmental Science & Engineering 2017年第3期11卷 131-140页

作者： Xiaoyan Song Rui Liu Lujun Chen Baogang Dong Tomoki Kawagishi Zhejiang Provincial Key Laboratory of Water Science and Technology Department of Environment in Yangtze Delta Region Institute of Tsinghua University-Zhejiang Jiaxing 314006 China School of Environment Tsinghua University Beijing 100084 China Aqua Development Center Mitsubishi Rayon Co. Ltd. Toyohashi 4408601 Japan

An intermittently aerated sequencing batch reactor （IASBR） and a traditional sequencing batch reactor （SBR） were parallelly constructed to treat digested piggery wastewater, which was in high NH4＋ -N concentration but in a low COD/TN ratio. Their pollutant removal perfonnance was compared under COD/TN ratios of 1.6-3.4 d and hydraulic retention times of 5 3 d. The results showed that the IASBR removed TN, NH4＋-N and TOC more efficiently than the SBR. The average removal rates of TN, NH4＋-N and TOC were 83.1%, 96.5%, and 89.0%, respectively, in the IASBR, significantly higher than the corresponding values of 74.8%, 82.0%, and 86.2%. in the SBR. Mass balance of organic carbon revealed that the higher TN removal in the IASBR might be attributed to its efficient utilization of the organic carbon for denitrification, since that 48.7%- 52.2% of COD was used for denitrification in the IASBR, higher than the corresponding proportion of 43.1%-47.4% in the SBR. A prc-anoxic process in the IASBR would enhance the ammonium oxidation while restrict the nitrite oxidation. Anoxic duration of 40-80 min should be beneficial for achieving stable nitritation.

关键词： Anoxic stress Carbon source Digested piggery wastewater Intermittently aerated SBR （IASBR）Total nitrogen