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Fault-alarm-threshold optimization method based on interval evidence reasoning

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Science China(Information Sciences) 2019年第8期62卷 201-203页

作者： Zhijie ZHOU Taoyuan LIU Guanyu HU Wei he Fujun ZHAO Gailing LI Rocket Force University of Engineering College of Information Science and Technology Hainan Normal University School of Computer Science and Technology Harbin University of Science and Technology

Dear editor,Fault alarm threshold is an important parameter of a system used to monitor the condition of industrial equipment. Therefore, reasonably setting the fault alarm threshold and reducing both false negative and positive rate (FNPR) are vital for improving the efficiency of industrial operations and ensuring the safety and reliable operation of

关键词： Fault-alarm-threshold optimization method based on interval evidence reasoning

Preparation of hollow-fiber nanofiltration membranes of high performance for effective removal of PFOA and high resistance to BSA fouling

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Journal of Environmental Sciences 2022年第12期34卷 14-24页

作者： Wenjing Tang Yunyi meng Bin Yang Dongyu he Yan Li Bojun Li Zheming Shi Changwei Zhao College of Resources and Environmental Sciences China Agricultural UniversityBeijing 100193China Key Laboratory of Drinking Water Science and Technology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China The Fourth Construction CO.LTD of China Electronics System Engineering Tianjin 300130China State Key Laboratory of Water Environment Simulation School of EnvironmentBeijing Normal UniversityBeijing 100875China

Nanofiltration(NF)process has become one of the most promising technologies to remove micro-organic combined water *** a NF membrane material with efficient separation for perfluorooctanoic acid(PFOA)combined pollution is highly desired,this manuscript targets this unmet need *** this work,hydrophilic SiO_(2)nanoparticles with various contents blended with carboxylic multiwalled carbon nanotube were used to modify poly(m-phenylene isophthal amide)(SiO_(2)/CmWCNT/PmIA)hollow fiber NF *** modified membrane with 0.1 wt%SiO_(2)doping exhibits way better fouling resistance with irreversible fouling ratio decreased dramatically from 18.7%to 2.3%,and the recovery rate of water flux increases significantly from 81.2%to 97.7%.The separation experiment results had confirmed that the modified membrane could improve the rejection from 97.2%to 98.6%for perfluorooctanoic acid(PFOA)and its combined pollution with bovine serum albumin(BSA).It is clear that this reported SiO_(2)/CmWCNT/PmIA hollow fiber NF membrane potentially could be applied in water *** research also provides a theoretical basis for efficiently removal of PFOA and its combined pollution by NF membrane.

关键词： Nanofiltration SiO_(2)nanoparticles Perfluorooctanoic acid Combined pollution Water treatment

Use of rare earth elements in single-atom site catalysis:A critical review——Commemorating the 100th anniversary of the birth of Academician Guangxian Xu

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Journal of Rare Earths 2021年第3期39卷 233-242,I0001页

作者： Ningqiang Zhang Han Yan Lingcong Li Rui Wu Liyun Song Guizhen Zhang Wenjun Liang Hong he Key Laboratory of Beijing on Regional Air Pollution Control and Beijing Key Laboratory for Green Catalysis and Separation Beijing University of TechnologyBeijing 100124China Department of Chemistry Tsinghua UniversityBeijing 100084China Collaborative Innovation Center of Electric Vehicles in Beijing Beijing 100081China

Rare earth metals are strategic resources with potential applications in optics,metallurgy and *** recent years,single-atom site catalysts(SASCs) have attracted increasing attention owing to their 100%atom efficiency and unique catalytic *** the past decade,rare earth elements,including rare earth metals and their oxides,have shown great potential in ***,systematic analyses of data are still *** this mini-review,the use of rare earth metals and their oxides in SASCs was summarized and the results are discussed.A particular focus was paid to the synthetic strategies,characterization of rare earth-containing SASCs,and applications as catalysis supports,promoters and active *** issues faced by rare-earth metals and their oxides in SASCs,as well as future prospects were also provided.

关键词： Rare earth catalysis Single-atom site catalysis Synthetic strategies Characterization Applications

Influences of electric pulse on solidification structure of Lm-29 Al-Si alloy

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China Foundry 2010年第2期7卷 153-156页

作者： he Lijia Wang Jianzhong Qi Jingang Du Huiling Zhao Zuofu College of material Science and Engineering Liaoning University of Technology Jinzhou 121001 China

The metallographic structure of Lm-29 aluminum-silicon alloy modified by electric pulse treatment has been investigated and compared with those *** solidification structure of Lm-29 alloy has been analyzed by means of m1AP3 Quantimet image processing and analysis system,and then the solidification process has been analyzed by means of differential scanning calorimetry(DSC).The results indicate that the primary silicon phase was refined remarkably by electric pulse while the tensile strength and elongation properties increased *** pulse treatment can also increase the binding power between silicon clusters and alloy melt matrix,as a result,the precipitation of primary silicon phase is suppressed to meet the demand of supercooling degree for nucleating,*** electric pulse modification has great influence on the size of silicon atomic cluster as well as its distribution in the melt,subsequently,leads to the refinement of solidification structure.

关键词： electric pulse modification Lm-29 alloy primary phase cluster

In vitro corrosion behavior of the extruded mg–4Zn–1mn alloy in different physiological solutions for biomedical applications

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Progress in Natural Science:materials International 2023年第4期33卷 467-477页

作者： Yang Zheng he Tong Jiawen Liu Jia Lu Weirong Li Fangfei Liu Ziyue Zhang Yan Li School of Aeronautics and Astronautics Tiangong University School of mechanical Engineering Tiangong University Dongguan Eontec Co.Ltd. School of materials Science and Engineering Beihang University

The extruded mg–4Zn–1mn alloy was prepared and its in vitro corrosion behavior in different physiological solutions of simulated body fluid(SBF), artificial saliva(AS) and artificial urine(AU) was investigated for biomedical applications. The microstructural characterization by optical microscope(Om), X-ray diffractometer(XRD), scanning electron microscopy(SEm) and energy dispersive X-ray spectrometer(EDS) showed that the alloy with an average grain size of approximate 20 μm was mainly composed of α-mg matrix phase along with some mgZn2and α-mn precipitates. The results of electrochemical corrosion and immersion corrosion tests revealed a distinct corrosion behavior for the alloy in different solutions with increasing immersion time. The corrosion morphologies were featured with flocculent precipitates in the SBF, flower-like clusters in the AS and columnar crystals in the AU. The alloy exhibited highest corrosion resistance and lowest corrosion rate in the AS compared with the SBF and the AU, which was attributed to the formation of a stable corrosion products layer.

关键词： Biodegradable metals mg-4Zn-1mn alloy Physiological solutions Corrosion behavior

Electron Beam-Physical Vapor Deposited TiAl-based Laminated Composite Sheet with Nb Layer Toughening

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Chinese Journal of Aeronautics 2006年第B12期19卷 5-8页

作者： ZHANG De-ming CheN Gui-qing HAN Jie-cai mENG Song-he Center for Composite materials Harbin Institute of Technology Harbin 150080 China

The TiAl-based laminated composite sheet of 150 mm × 100 mm × 0.2 mm, with 24 TiAl layers and 23 Nb layers laid alternately one on another, was successfully fabricated using the electron beam-physical vapor deposition （EB-PVD） method. The microstructure and properties of the sheet were investigated on an atomic force microscope （AFm）, a scanning electron microscope （SEm） and a tensile testing machine. The results indicate that the evenly distributed Nb layers are well joined with the TiAl layers, and the interfaces between layers are transparent, and every interlayer spacing is of about 8μm. The fractures appear to be a mixture of intergranular fractures and somewhat ductile quasi-cleavage ones. Despite its slight influence on ultimate tensile strength, the inserts of Nb layers efficiently increase the room temperature ductility of TiAl-based alloys due to the crack deflection effect.

关键词： EB-PVD TiAl-based alloys sheet TiAl/Nb laminated composites microstructure and properties

metal-organic framework-derived CoSn/NC nanocubes as absorbers for electromagnetic wave attenuation

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Journal of materials Science & Technology 2022年第13期108卷 236-243页

作者： Chenxi Wang Zirui Jia Shuangqiao he Jixi Zhou Shuo Zhang mengli Tian Bingbing Wang Guanglei Wu Institute of materials for Energy and Environment State Key Laboratory of Bio-fibers and Eco-textilesCollege of Materials Science and EngineeringQingdao UniversityQingdao 266071China College of Chemistry and Chemical Engineering Qingdao UniversityQingdao 266071China Weihai Innovation Institute Qingdao UniversityWeihai 264200China

metal-organic framework-derived composites have been widely used in electromagnetic wave(EmW)absorption,but the traditional synthetic strategy greatly limits the structure and species of *** research provided a solvent-free method to synthesize Co-mOF and its *** CoSnO_(3)as the precursor,the preparation of Co-mOF is achieved by bridging the cobalt(II)ion of CoSnO_(3)and the 2-methylimidazole *** CoSn/N-doped carbon(CoSn/NC)composites derived from CoSnO_(3)-mOF(Co-mOF with CoSnO_(3)as Co source)retain the original morphology of CoSnO_(3).Besides,the polarization effect produced by the N-doped carbon layers also benefits the excellent EmW absorption performance of the CoSn/NC *** is reflected in the minimum reflection loss(RL)of-48.2 dB at 2.2 mm and the effective bandwidth(EBA)of 5.84 *** work provides a new channel to the construction of Co-mOFs,which could be extended to other Co-based oxides and vastly expand the species of mOFs based on metallic Co.

关键词： Hollow nanocubes structure N-doped carbon CoSnO_(3)-mOF Electromagnetic wave absorption

Choroidal thickness in pregnant women : a cross-sectional study

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International Journal of Ophthalmology(English edition) 2016年第8期9卷 1200-1206页

作者： Ru Liu Guo-Ping Kuang Di-Xian Luo Xiao-he Lu Department of Ophthalmology Zhujiang Hospital of Southern Medical University Department of Ophthalmology the First People's Hospital of Chenzhou Institute of Translational medicine the First People's Hospital of Chenzhou

AIm: To investigate choroidal thickness in pregnant women and compare the measurements with those of normal nonpregnant women. mETHODS: Using enhanced depth imaging optical coherence tomography (EDI-OCT), choroidal thickness was measured at the fovea and at 1 mm and 3 mm superior, inferior, temporal, and nasal to the fovea in both healthy pregnant women and nonpregnant women. Pearson correlation analysis was performed to evaluate the relationships between subfoveal choroidal thickness (SFCT) and the demographic and ocular parameters. Pooled odds ratio (OR) and 95% confidence interval (CI) were calculated using fixed-effects model when meta analyses were conducted. RESULTS: Comparison of choroidal thickness between the groups showed that it was significantly greater in healthy pregnant women's eyes than in normal nonpregnant women's eyes at all locations except at 3 mm superior and 3 mm temporal from the fovea (Phe mean SFCT was 344.13 +/- 50.94 mu m in healthy pregnant women's eyes and 315.03 +/- 60.57 mu m in normal nonpregnant women's eyes, with a statistically significant difference (P=0.008). Pearson correlation analysis showed that age and axial length were significantly related to SFCT in healthy pregnant women, normal nonpregnant women, and all subjects. The results of our cross-sectional study were consistent with the results of the further meta analysis, with a pooled weighted mean difference (WmD) of 33.66 mu m (95% CI: 26.16 to 41.15) for SFCT. CONCLUSION: Our results, along with the comprehensive meta-analysis, suggest that choroidal thickness in healthy pregnant women is greater than that in normal nonpregnant women.

关键词： choroidal thickness pregnant optical coherence tomography

The characteristics of waves around an entrance of a lagoon in South China Sea

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Journal of Hydrodynamics 2021年第5期33卷 889-900页

作者： Zhi-wen Cai Chun-rong he Xiao-long Liu Wen-wei Chen Ze Sun Jun Ding China Ship Scientific Research Center Wuxi 214082China Southern marine Science and Engineering Guangdong Laboratory(Zhanjiang) 524000China

The characteristics of the waves around a lagoon entrance in South China Sea were observed during the past one and half years based on the wave *** measured results show that the monsoon plays an important *** summer,waves mostly come from the southeast,among which the wave components of non-dimensional periods larger than 0.2 are fetch-trapped *** winter the waves may be divided into two groups,the fetch-trapped waves and the waves from the open *** skewness of the directional distribution functions is within+8 around *** power relationship between the direction spread and kurtosis is also ***,it is found that the waves with the significant wave heights greater than 1.5 m are caused by typhoons or cold *** frequency components of wave energy driven by cold air appear in the high frequency range at first,and change to the lower frequency range *** waves driven by typhoon mostly come from the open sea.

关键词： Reef lagoon cold air typhoon waves South China Sea Introduction