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Investigation and assessment of micropollutants and associated biological effects in wastewater treatment processes

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Journal of Environmental Sciences 2020年第8期32卷 119-127页

作者： Xiaoyan Y.Ma Ke dong Lei tang Yongkun Wang Xiaochang C.Wang Huu hao Ngo Rong Chen Na Wang International Science&Technology Cooperation Center for Urban Alternative Water Resources Development Key Lab of Northwest Water ResourceEnvironment and EcologyMOEEngineering Technology Research Center for Wastewater Treatment and ReuseShaanxi ProvinceShaanxi Key Laboratory of Environmental EngineeringXi’an University of Architecture and TechnologyXi’an 710055China School of Civil and Environmental Engineering Faculty of Engineering and Information TechnologyUniversity of Technology SydneyBroadwayNSW 2007Australia School of Architecture and Civil Engineering Xi’an University of Science and TechnologyXi’an 710054China

Currently,the wastewater treatment plants(WWTPs)attempt to achieve the shifting from general pollution parameters control to reduction of organic micropollutants ***,they have not been able to satisfy the increasing ecological safety *** this study,the removal of micropollutants was investigated,and the ecological safety was assessed for a local *** the total concentration of 31 micropollutants detected was reduced by 83%using the traditional biological treatment processes,the results did not reflect chemicals that had poor removal efficiencies and low *** the five categories of micropollutants,herbicides,insecticides,and bactericides were difficult to remove,pharmaceuticals and UV filters were effectively *** specific photosynthesis inhibition effect and non-specific bioluminescence inhibition effect from wastewater were detected and evaluated using hazardous concentration where 5%of aquatic organisms are *** photosynthesis inhibition effect from wastewater in the WWTP was negligible,even the untreated raw ***,the bioluminescence inhibition effect from wastewater which was defined as the priority biological effect,posed potential ecological *** decrease non-specific biological effects,especially of macromolecular dissolved organic matter,overall pollutant reduction strategy is ***,the ozonation process was used to further decrease the bioluminescence inhibition effects from the secondary effluent;≥0.34 g O 3/g DOC of ozone dose was recommended for micropollutants elimination control and ecological safety.

关键词： Micropollutants Biological effect Wastewater treatment Ecological safety Ozonation

Vacuum degree effects on betavoltaics irradiated by ^(63)Ni with differently apparent activity densities

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Science China(Technological Sciences) 2017年第2期60卷 282-288页

作者： LIU YunPeng XU ZhiHeng WANG hao tang XiaoBin Department of Nuclear Science and Engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016 China jiangsu Key Laboratory of Material and Technology for Energy Conversion Nanjing 210016 China

For many current betavoltaics, beta sources and PN junction energy conversion units are separated. The air gap between the two parts could stop part of decay beta particles, which results in inefficient performance of the betavoltaic. By employing 63Ni with an apparent emission activity density of 7.26×10~7 and 1.81×10~8 Bq cm^(-2), betavoltaic performance levels were calculated at a vacuum degree range of 1×10~5 to 1×10^(-1) Pa and measured at 1.0×10~5 and 1.0×10~4 Pa, respectively. Results show that betavoltaic performance levels improve significantly as the vacuum degree increases. The maximum output power (P_(max)) exhibits the largest change, followed by short-circuit current (I_(sc)), open-circuit voltage (V_(oc)), and fill factor. The vacuum degree effects on Isc, Voc,and Pmax of the betavoltaic with low apparent activity density 63Ni are more significant than those of the betavoltaic with high apparent activity density ^(63)Ni. Moreover, the improved efficiencies of the measured performances are larger than the calculated efficiencies because of the low ratio of Isc and reverse saturation current (I_0). The values of I0, ideality factor, and shunt resistance were estimated to modify the equivalent circuit model. The calculation results based on this model are closer to the measurement results. The results of this research can provide a theoretical foundation and experimental reference for the study of vacuum degree effects on betavoltaics of the same kind.

关键词： vacuum degree betavoltaic apparent activity density energy conversion unit MCNP5

Distinct effect of preparation methods on reaction efficiency of Mn-Ce/Al_(2)O_(3) catalysts in low-temperature NH_(3)-SCR

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Journal of Rare Earths 2024年第10期42卷 1865-1872页

作者： Shijie hao Yandi Cai Wei Wei Yanan Lv Jiawei Ji Wei Tan Jingfang Sun Liwei Jia Changjin tang Lin dong State Key Laboratory of Pollution Control and Resource Reuse School of EnvironmentJiangsu Key Laboratory of Vehicle Emissions ControlCenter of Modern AnalysisKey Laboratory of Mesoscopic Chemistry of MOESchool of Chemistry and Chemical EngineeringNanjing UniversityNanjing210023China Wuxi Weifu Environmental Catalysts Co. LtdWuxi214028China School of Environment Nanjing Normal UniversityNanjing210023China

In this study,a series of Mn-Ce/Al_(2)O_(3) catalysts was prepared by different methods of depositionprecipitation(MnCeAl-DP),impregnation(MnCeAl-IM) and citric acid(MnCeAl-CA),and the distinct effect of preparation methods on NO_(x) removal performance at low temperature was *** show that MnCeAl-DP exhibits not only the best activity but also the highest resistance against SO_(2)/H_(2)*** the assistance of comprehensive characterizations from scanning electron microscopy(SEM),Brunauer-Emmett-Teller(BET),X-ray diffraction(XRD),H_(2)-temperature programmed reduction(H_(2)-TPR),NH_(3)-te mperature programmed deso rption(NH_(3)-TPD),and X-ray photoelectron spectroscopy(XPS),it is revealed that the MnCeAl-DP sample owns admired features of large surface area and pore volume,enriched Mn^(4+) and chemisorbed oxygen species originating from enhanced interaction between MnO_x and CeO_(2),as well as improved adsorption capacity to NH_(3) and *** these factors contribute to activity *** in-situ DRIFTS studies reveal that the improvement of NH_(3)-SCR performance over MnCeAI-DP is related to the formation of abundant nitrate species,which is beneficial to the "NH_(4)NO_(3)" reaction pathway and thus enhances low-temperature activity.

关键词： Mn-Ce/Al_(2)O_(3)catalysts NH_(3)-SCR Low temperature NH_(4)NO_(3) Fast SCR Rare earths

Controller area network node reliability assessment based on observable node information

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Frontiers of Information Technology & Electronic Engineering 2017年第5期18卷 615-626页

作者： Lei-ming ZHANG Long-hao tang Yong LEI State Key Laboratory of Fluid Power Transmission and Mechatronics Zhejiang UniversityHangzhou 310027China

Controller area network(CAN) based fieldbus technologies have been widely used in networked manufacturing systems. As the information channel of the system, the reliability of the network is crucial to the system throughput, product quality, and work crew safety. However, due to the inaccessibility of the nodes' internal states, direct assessment of the reliability of CAN nodes using the nodes' internal error counters is infeasible. In this paper, a novel CAN node reliability assessment method, which uses node's time to bus-off as the reliability measure, is proposed. The method estimates the transmit error counter(TEC) of any node in the network based on the network error log and the information provided by the observable nodes whose error counters are ***, a node TEC estimation model is established based on segmented Markov chains. It considers the sparseness of the distribution of the CAN network errors. Second, by learning the differences between the model estimates and the actual values from the observable node, a Bayesian network is developed for the estimation updating mechanism of the observable nodes. Then, this estimation updating mechanism is transferred to general CAN nodes with no TEC value accessibility to update the TEC estimation. Finally, a node reliability assessment method is developed to predict the time to reach bus-off state of the nodes. Case studies are carried out to demonstrate the effectiveness of the proposed methodology. Experimental results show that the estimates using the proposed model agree well with actual observations.

关键词： Controller area network(CAN) Transmit error counter(TEC) TEC value estimation Bayesian network Bus-off hitting time

Mechanical properties and surface characteristics of SiC fibers irradiated by swift heavy ions

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Nuclear Science and Techniques 2022年第9期33卷 37-47页

作者： Li-Qing Zhang Chong-Hong Zhang Chen-Chun hao Guo-dong Hu Zheng-dong Feng Yong-Jian tang Wen-Kun Zhu Jian-Yang Li Qing Huang Southwest University of Science and Technology Mianyang 621010China Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China Ningbo Institute of Materials Technology and Engineering Chinese Academy of SciencesNingbo 315201China

SiC fibers were irradiated by 414.4-MeV^(112)Sn^(27.3+)ions to different fluences(5.0×10^(12),6.0×10^(13),1.6×10^(14),and 1.92×10^(15)ions/cm^(2)).^(112)Sn^(27.3+)deposited its energy mainly via electron energy loss and passed through the SiC ***,the mechanical properties and surface characteristics of fibers were studied using a specific single filament tensile test and field emission scanning electron *** revealed that the carbon concentration on the fiber surface increased while the silicon concentration ***,the addition of oxygen was found to correlate with an increase in ion ***,the fiber surface morphology of the least fluence(5.0×10^(12)ions/cm^(2))irradiated specimen displayed no obvious changes and its diameter was slightly *** successive increases of ion fluence,large grains/bubbles on the fiber surface first appeared and then disappeared,and the diameter of fibers evidently ***,at the highest fluence(1.92×10^(15)Sn ions/cm^(2))irradiated specimen,some fibers were brittle *** a result,the mean tensile strength and the average elastic modulus of the fibers generally decreased with respect to the ion *** degradation mechanisms of mechanical properties of SiC fibers under irradiation are discussed in detail.

关键词： SiC fibers Swift-heavy-ion irradiation FE SEM Tensile test

Nanomechanical and Chemical Mapping of the Structure and Interfacial Properties in Immiscible Ternary Polymer Systems

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Chinese Journal of Polymer Science 2021年第6期39卷 651-658,I0004页

作者： hao-Xuan Li Thomas PRussell dong Wang State Key Laboratory of Organic-Inorganic Composites&Beijing Advanced Innovation Center for Soft Matter Science and Engineering Beijing University of Chemical TechnologyBeijing 100029China Polymer Science and Engineering Department University of Massachusetts AmherstMassachusetts 01003United States Materials Sciences Division Lawrence Berkeley National Laboratory1 Cyclotron RoadBerkeleyCalifornia 94720United States

It is a challenge to identify each phase in a multi-component polymer system and uniquely determine the interfacial properties between the different *** atomic force microscopy nanomechanical mapping(AFM-NM)and AFM-based infrared spectroscopy(AFM-IR),we identify each phase,visualize structural developments,and determine the interfacial properties in a blend of three polymers:high-density polyethylene(HDPE),polyamide(PA6)and poly(styrene-b-ethylene-co-butylene-b-styrene)(SEBS).Each phase can be identified from the Young’s modulus,along with the structural development within the phases before and after *** interfacial widths between HDPE/PA6,HDPE/SEBS and SEBS/PA6 were determined independently in one measurement from a Young’s modulus *** structural,mechanical property development and identity of the phases were determined by AFM-NM,while AFM-IR,providing complementary chemical information,identified interfacial reactions,showed the chemical affinity of a compatibilizer with the component phases,and mapped the distribution of the compatibilizer in the ternary polymer *** chemical,structural and interfacial information obtained by these measurements provide information that is essential for producing mechanically robust materials from incompatible mixtures of polymers.

关键词： AFM nanomechanical mapping AFM infrared spectroscopy Multi-component systems Interfacial structure Interfacial properties

Cathodic reduction process of Al-Cu-Y alloy in fluoride-oxide eutectic system via molten salt electrolysis

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Journal of Rare Earths 2018年第3期36卷 324-330页

作者： Xu Wang Chunfa Liao Yunfen Jiao hao tang School of Metallurgy and Chemical Engineering Jiangxi University of Science and Technology

Al-Cu-Y alloys were prepared by molten salt electrolysis in fluoride-oxide system composed of electrolyte（Na3 AlF6-AlF3-LiF-MgF2） and oxide（Al2 O3-CuO-Y2 O3）. Cathodic reduction process of Al2 O3,CuO and Y2 O3 were analyzed by cyclic voltammetry and chronoamperometry. Components and phase composition of alloy samples prepared by potentiostatic electrolysis were characterized by scanning electron microscopy and energy dispersive spectroscopy. The results show that the Al-Cu-Y alloy can be prepared in the AIF3-NaF-5 wt%LiF-5 wt%MgF2（NaF/AlF3 = 2.2, molecular ratio） eutectic system with mixed oxide（Al2 O3-CuO-Y2 O3） through 2 h at the conditions of a temperature of 1208 K, cell voltage3.0 V, cathode current density 0.7 A/cm^2. Al（Ⅲ） and Cu（Ⅱ） ions can be reduced to zero valence Al（0） and Cu（0） directly on carbonaceous electrode surface by instantaneous nucleation, respectively, the reduction process is controlled by diffusion. The reduction potential of Y（Ⅲ） ions is close to the active ions of fluoride melts, but strengthened phase AI3 Y can be formed through electrochemical reduction and alloyed process with active Al（Ⅲ） and Cu（Ⅱ） ions, meanwhile, the Al2 Cu and Al3 Y phases are distributed at the grain boundary of Al matrix.

关键词： Fluoride-oxide eutectic Al-Cu-Y alloy Molten salt electrolysis Cyclic voltammetry Electrode process Rare earths

Recent advances in vacancy engineering for reliable lithiumsulfur batteries

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Rare Metals 2024年第2期43卷 455-477页

作者： Wen-dong Liu Xiao tang Jun-An Feng Chao-Yue Zhang hao Liu Chuan Shi Xiao-Xian Zhao Jian-Jun Song College of Physics School of Chemistry and Chemical EngineeringQingdao UniversityQingdao266071China Faculty of Science Centre for Clean Energy TechnologySchool of Mathematical and Physical SciencesUniversity of Technology SydneySydneyNSW2007Australia Department of Chemistry College of ScienceHebei Agricultural UniversityBaoding071001China

The high-energy-density and low-cost features endow lithium-sulfur batteries with broad application ***,many drawbacks,especially the detrimental shuttle effect,have hindered the further development of *** response,a lot of new structures have been applied to suppress the shuttle effect and promote the development of ***,vacancy engineering has gained the attention of researchers due to its unique electronic *** review aims to analyze the application of vacancy engineering in ***,the electrochemistry of LSBs has been systematically discussed and the existing challenges as well as improvement tactics of LSBs have also been ***,the preparation methods and characterization technologies of various vacancies are summarized,including oxygen vacancies,sulfur vacancies,selenium vacancies,other anion vacancies,cation vacancies,*** latest applications of vacancy engineering in LSBs are also summarized in this ***,some prospects and insights for further investigation and practical application of vacancy engineering in LSBs are put forward.

关键词： Lithium-sulfur batteries(LSBs) Defects Vacancy engineering Electronic structure Shuttle effect

Dual characteristic of trace rare earth elements in a commercial casting Al-Cu-X alloy

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Rare Metals 2015年第5期34卷 308-313页

作者： Li Fan Qi-tang hao Wen-Ke Han State Key Laboratory of Solidification Processing Northwestern Polytechnical University School of Materials Science and Engineering Northwestern Polytechnical University

The effect of rare earth elements on microstructure and mechanical properties of casting Al-Cu-X alloy （X = Mn, Ti, V, Cd, Zr） was investigated in as-cast and T6 conditions. Microstructure evolution was characterized by optical microscopy, scanning electron microscopy, and transmission electron microscopy. RE-containing intermetallic compounds （IMCs） formed in this alloy were indentified by X-ray diffraction （XRD） and energy dispersive spectroscopy （EDS）. It is shown that the additions of RE （60Ce-40La, wt%） result in the formation of Ce-rich blocky-shaped A12o（Ti, V）2RE and La-rich skeletal-shaped A18Cu4RE. Tensile results of samples after T6 treatment indicate that the strength and ductility increase slightly to 480 MPa and 9.7 %, respectively, with RE content increasing from 0 wt% to 0.3 wt%. This is due to the combinative hardening effects of reduced grain size, enhanced precipitation of 0＇（Al2Cu） phase and Al20 Cu2Mn3 dispersed particles, and minor La-rich IMCs at the grain boundaries of α-Al dendrites. The decrease of strength of 0.5 wt% RE-added sample is ascribed to the aggregation of Al20（Ti, V）2RE IMCs inside the grains. The dual characteristic of rare earth elements was also discussed in terms of its positive and negative effects on mechanical properties.

关键词： Aluminum alloys Rare earth Microstructure Mechanical property Intermetallic compounds