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Bipartite Locating Array

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Acta Mathematica Sinica,English Series 2020年第2期36卷 179-188页

作者： zong feng QI Wen Jie ZHONG yu TANG State Key Laboratory of Complex Electromagnetic Environment Effects on Electronics and Information System(CEME叭Luoyang 471003 P.R.China School of Mathematical Sciences Soochow UniversitySuzhou 215006P.R.China

As a special case of experimental design,locating array is useful for locating interaction faults in component-based systems.In this paper,bipartite locating array is proposed to locate interaction faults between two specific groups.Such arrays are especially suitable for antagonism tests.Based on the definition of bipartite locating array,the lower bound on run sizes are established to measure the optimality for specific parameters.When a single fault is to be located,optimal bipartite locating arrays are proved to be equivalent to certain specific combinatorial configurations.As a result,approaches to constructing optimal bipartite locating arrays are proposed and some infinite classes of optimal bipartite locating arrays are obtained using the corresponding construction met hod.

关键词： Bipartite locating arrays interaction faults lower bound optimality

Separation and purification of Yb_(2)O_(3) by ion exchange chromatography and preparation of ultra-high purity Yb_(2)O_(3)

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稀有金属:英文版 2023年第8期42卷 2725-2735页

作者： Xi-Juan Pan Zhi-Qing Yang Yang Xu Meng Wang Xiao-Wei Huang zong-yu Feng Qiang Zhong Xin-Lin Peng National Engineering Research Center for Rare Earth China GRINM Group Co.Ltd.Beijing 100088China GRIREM HI-TECH Co. Ltd.Langfang 065201China GRIREM Advanced Materials Co. Ltd.Beijing 100088China General Research Institute for Nonferrous Metals Beijing 100088China

Ultra-high purity Yb_(2)O_(3) is the critical material of many high-tech materials such as laser glass and fiber,in which impurities seriously affect the laser color quality,intensity and power.In order to reduce the influence of impurities on the properties of laser materials,the purification process of Yb_(2)O_(3) was studied by comparing two kinds of resins(RT-1 and RS-1)using improved ion-exchange chromatography(IEC)method.In this study,through the synergistic improvement of resin structure and eluting system,the environmental pollution caused by ammonia water in the traditional IEC method was reduced,and the requirements of high temperature and pressure were cut.The ion exchange behavior and impurity removal mechanism in the resin column during the loading and eluting process were compared and analyzed.The experimental results show that RS-1 resin is all superior to RT-1resin in elements selectivity,ion exchange capacity and impurities removal rate.After separation and purification by IEC with RS-1 resin,the total removal rate of rare earth impurities was 77.59%and that of non-rare earth impurities was 95.86%when Yb recovery was more than 70%,both higher than that of RT-1 resin(73.26%and 83.18%).This indicates that the improved IEC method is very effective in separating and removing different metal impurities from Yb_(2)O_(3).The pilot test results of IEC method separating and purifying Yb_(2)O_(3) with RS-1 resin show that the purity of Yb_(2)O_(3) can be increased from 99.9929%to 99.9997%by IEC method.It has exhibited huge potential of preparing ultra-high purity Yb_(2)O_(3),especially the deep removal of non-rare earth impurities.

关键词： Ultra-high purity Yb_(2)O_(3) Ion exchange chromatography(IEC) Laser fiber Separation mechanism Impurities

Short-term Association of Meteorological Elements on COVID-19 Pandemic in a Semi-arid City of Northwest China,2021-2022

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Biomedical and Environmental Sciences 2024年第5期37卷 537-542页

作者： feng feng Liu MA yu Xia CHENG Bo Wen LIU zong Rui ZHAO yu Han YANG Jie College of Atmospheric Sciences Key Laboratory of Semi-Arid Climate ChangeMinistry of EducationLanzhou UniversityLanzhou 730000GansuChina Minhe Meteorological Bureau Minhe 810800QinghaiChina

The coronavirus disease 2019(COVID-19)outbreak in late 2019 significantly impacted global health.The virus’s rapid spread,with its long incubation period and high infection level,caused substantial disruption to regular social frameworks,production,and lifestyles^([1]).COVID-19 is primarily transmitted through close contact,long-range contaminants,and airborne routes.

关键词： Northwest COV primarily

Modal Parameter Identification Method of Jacket Platform Structure Based on AFDD and Optimized FBFFT

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China Ocean Engineering 2023年第3期37卷 393-407页

作者： LENG Jian-cheng MA Jin-yong FAN zong-heng QIAN Wan-dong feng Hui-yu School of Mechanical Science and Engineering Northeast Petroleum UniversityDaqing 163318China

Offshore platforms are susceptible to structural damage due to prolonged exposure to random loads,such as wind,waves,and currents.This is particularly true for platforms that have been in service for an extended period.Identifying the modal parameters of offshore platforms is crucial for damage diagno sis,as it serves as a prerequisite and foundation for the process.Therefore,it holds great significance to prioritize the identification of these parameters.Aiming at the shortcomings of the traditional Fast Bayesian Fast Fourier Transform(FBFFT) method,this paper proposes a modal parameter identification method based on Automatic Frequency Domain Decomposition(AFDD) and optimized FBFFT.By introducing the AFDD method and Powell optimization algorithm,this method can automatically identify the initial value of natural frequency and solve the objective function efficiently and simply.In order to verify the feasibility and effectiveness of the proposed method,it is used to identify the modal parameters of the IASC-ASCE benchmark model and the j acket platform structure model,and the Most Probable Value(MPV) of the modal parameters and their respective posterior uncertainties are successfully identified.The identification results of the IASC-ASCE benc hmark model are compared with the identification re sults of the MODE-ID method,which verifies the effectivene ss and accuracy of the proposed method for identifying modal parameters.It provides a simple and feasible method for quantifying the influence of uncertain factors such as environmental parameters on the identification results,and also provide s a reference for modal parameter identification of other large structures.

关键词： jacket platform uncertain modal parameter identification FBFFT method environmental excitation AFDD method Powell optimization

Technology development for rare earth cleaner hydrometallurgy in China

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Rare Metals 2015年第4期34卷 215-222页

作者： Xiao-Wei Huang Zhi-Qi Long Liang-Shi Wang zong-yu Feng National Engineering Research Center for Rare Earth Materials General Research Institute for Nonferrous Metals Grirem Advanced Materials Co. Ltd.

China is the global leader in rare earth （RE） production using hydrometallurgical processes. Advantageous extraction techniques of rare earths from Baotou mixed rare earth minerals, bastnaesite, and ion-adsorption clays of rare earth deposits have been developed in China. The separation and purification technologies have also achieved rapid development. The industrial application processes for rare earth hydrometallurgy were summarized in the present paper. With the large demands and rapid development of rare earths, the issues of resources and environment are more prominent. This review gives an overview of the main processes that were developed in the past toward greener hydrometallurgy of rare earths in China. Based on the development of the rare earth industry, comprehensive utilization and cleaner production should still be focused on in the future, to support the sustainable development.

关键词： Rare earths Cleaner production Separation and purification Hydrometallurgy

Ethylene thiourea exposure induces neurobehavioral toxicity in zebrafish by disrupting axon growth and neuromuscular junctions

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Journal of Environmental Sciences 2024年第3期137卷 108-119页

作者： Jingming Wang Zhiquan yu Yongfeng Wang yuanyao Chen Lin Xiao Yanjun zong Qiyuan feng Lianqi Peng Huiping Zhang Chunyan Liu Institute of Reproductive Health Tongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China

Ethylene thiourea(ETU)converted from ethylene bisdithiocarbamate(EBDC)fungicides has aroused great concern because of its prevalence and harmful effects.Although ETU-induced neurotoxicity has been reported,the potential mechanisms remain unclear.This study provided insights into its neurotoxic effects at environmentally relevant concentrations in zebrafish.Our findings showed that embryonic exposure to ETU decreased the hatch rate and delayed somite development.Furthermore,ETU treatment significantly reduced the dark velocity in the locomotion assay.The upregulated tendency of the mitogen-activated protein kinases(MAPK)pathway(mknk1,atf4,mapkapk3)screened by transcriptome analysis implied motor neuron degeneration,which was validated by subsequent morphological observation,as axon length and branches were truncated in the 62.5μg/L ETU group.However,although the rescue experiment with a p38 MAPK inhibitor(SB203580)successfully ameliorated axon degeneration,it failed to reverse the locomotion behaviors.Further exploration of transcriptome data revealed the varied expression of presynaptic scaffold protein-related genes(pcloa,pclob,bsna),whose downregulation might impair the neuromuscular junction(NMJ).Therefore,we reasonably suspected that ETU-induced neurobehavioral deficits might result from the combined effects of the MAPK pathway and presynaptic proteins.Considering this,we highlighted the necessity to take precautions and early interventions for susceptible ETU-exposed populations.

关键词： Ethylene thiourea(ETU) Behavior Neuromuscular junction MAPK signaling pathway Piccolo and bassoon Danio rerio

Effects of short-term osmotic stress on leaf hydraulic conductivity and ZmPIPs mRNA accumulation in maize seedlings

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Journal of Integrative Agriculture 2016年第11期15卷 2497-2506页

作者： WANG Wei-feng zong yu-zheng ZHANG Sui-qi State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau/Institute of Soil and Water Conservation Northwest A & F University College of Forestry Shanxi Agricultural University College of Agriculture Shanxi Agricultural University

Plants maintain water balance by varying hydraulic properties, and plasma membrane intrinsic proteins（PIPs） may be involved in this process. Leaf xylem and root hydraulic conductivity and the m RNA contents of four highly expressed Zm PIP genes（Zm PIP1;1, Zm PIP1;2, Zm PIP2;2, and Zm PIP2;5） in maize（Zea mays） seedlings were investigated. Under well-watered conditions, leaf hydraulic conductivity（K_（leaf）） varied diurnally and was correlated with whole-plant hydraulic conductivity. Similar diurnal rhythms of leaf transpiration rate（E）, K_（leaf） and root hydraulic conductivity（K_（root）） in well-watered plants are important for maintaining whole-plant water balance. After 2 h of osmotic stress treatment induced by 10% polyethylene glycol 6000, the K_（root） of stressed plants decreased but K_（leaf） increased, compared with well-watered plants. The m RNA contents of four Zm PIPs were significantly up-regulated in the leaves of stressed plants, especially for Zm PIP1;2. Meanwhile, Zm PIP2;5 was significantly down-regulated in the roots of stressed plants. After 4 h of osmotic stress treatment, the E and leaf xylem water potentials of stressed plants unexpectedly increased. The increase in K_（leaf） and a partial recovery of K_（root） may have contributed to this process. The m RNA content of Zm PIP1;2 but not of the other three genes was up-regulated in roots at this time. In summary, the m RNA contents of these four Zm PIPs associated with K_（leaf） and K_（root） change in maize seedlings during short-term osmotic stress, especially for Zm PIP1;2 and Zm PIP2;5, which may help to further reveal the hydraulic resistance adjustment role of Zm PIPs.

关键词： maize short-term osmotic stress hydraulic conductivity ZmPIP

Talbot effect in nonparaxial self- accelerating beams with electromagnetically induced transparency

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Frontiers of physics 2020年第5期15卷 137-143页

作者： Jing-Min Ru Zhen-Kun Wu Ya-Gang Zhang feng Wen yu-zong Gu Institute of Nano/Photon Materials and Application School of Physics and ElectronicsHenan UniversityKaifeng 475004China National Demonstmtion Center for Experimental Physics and Electronics Education School of Physics and ElectronicsHenan UniversityKaifeng 475004China Key Laboratory for Physical Electronics and Devices of the Ministry of Education&School of Science&Shaanxi Key Lab of Information Photonic Technique&Institute of Wide Bandqap Semiconductors Xi'an Jiaotonq UniversityXi'an 710049China

In this study,we report on the fractional Talbot ffect of nonpar axial self-accelerating beams in a multilevel electromagnetically induced transparency(EIT)atomic configuration,which,to the best of our knowledge,is the first study on this subject.The Tallbot ffect originates from superposed eigenmodes of the Helmholtz equation and forms in the EIT window in the presence of both linear and cubic susceptibilities.The Talbot ffect can be realized by appropriately selecting the cofficients of the beam components.Our results indicate that the larger the radial difference between beam components,the stronger the interference between them,the smaller the Tallbot angle is.The results of this study can be useful when studying optical imaging.optical measurements,and optical computing.

关键词： multilevel atomic configuration nonparaxial self-accelerating beam Talbot effect electromagnetically induced transparency

Hot deformation behaviors of a 9Cr oxide dispersion-strengthened steel and its microstructure characterization

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International Journal of Minerals,Metallurgy and Materials 2019年第5期26卷 597-610页

作者： yu Shao Li-ming yu Yong-chang Liu zong-qing Ma Hui-jun Li Jie-feng Wu State Key Lab of Hydraulic Engineering Simulation and Safety Tianjin Key Lab of Composite and Functional Materials Tianjin University Institute of Plasma Physics Chinese Academy of Sciences

The hot deformation behaviors of a 9 Cr oxide dispersion-strengthened(9 Cr-ODS) steel fabricated by mechanical alloying and hot isostatic pressing(HIP) were investigated. Hot compression deformation experiments were conducted on a Gleeble 3500 simulator in a temperature range of 950–1100°C and strain rate range of 0.001–1 s^(-1). The constitutive equation that can accurately describe the relationship between the rheological stress and the strain rate of the 9 Cr-ODS steel was established, and the deformation activation energy was calculated as 780.817 kJ/mol according to the data obtained. The processing maps of 9 Cr-ODS in the strain range of 0.1–0.6 were also developed. The results show that the region with high power dissipation efficiency corresponds to a completely recrystallized structure. The optimal processing conditions were determined as a temperature range of 1000–1050°C with strain rate between 0.003 and 0.01 s^(-1).

关键词： hot deformation constitutive equations processing maps microstructural evolution