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基于混沌博弈优化的固体氧化物燃料电池模型参数优化设计

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电力系统保护与控制 2024年第6期52卷 15-28页

作者：马遵和鹏许珂玮孟贤何廷一杨博云南电网有限责任公司电力科学研究院云南昆明650000 昆明理工大学电力工程学院云南昆明650500

固体氧化物燃料电池(solid oxide fuel cell, SOFC)因具有转换效率高、无污染物排放、运行噪声低等特点被视为前景广阔的绿色发电技术之一,其被广泛应用于电力系统和交通运输等领域。针对SOFC稳态模型的参数优化设计问题,提出了一种基... 详细信息

固体氧化物燃料电池(solid oxide fuel cell, SOFC)因具有转换效率高、无污染物排放、运行噪声低等特点被视为前景广阔的绿色发电技术之一,其被广泛应用于电力系统和交通运输等领域。针对SOFC稳态模型的参数优化设计问题,提出了一种基于混沌博弈优化(chaosgameoptimization, CGO)方法的SOFCs参数提取框架。同时,利用芬兰燃料电池技术公司Elcogen生产的陶瓷阳极支撑型平板式低温单体燃料电池(ASC-400B)工作于两种不同温度(即600℃和700℃)下的实验数据以及美国蒙大拿州立大学开发的基于物理模型的5 kW级管式SOFC电池堆栈模型在两种不同温度(即850℃和950℃)下的仿真数据,分别对所提框架、蒲公英优化器(dandelion optimizer, DO)、平衡优化器(equilibrium optimizer, EO)、粒子群优化(particle swarm optimization, PSO)算法和白鲨优化器(white shark optimizer, WSO)的参数提取的性能进行了深入的研究和分析。测试结果表明:相比于DO、EO、PSO和WSO,CGO能够准确、稳定且快速地提取上述各种SOFCs的模型未知参数,为SOFCs的系统建模提供了一种高效的方法。

关键词：参数设计固体氧化物燃料电池系统建模混沌博弈优化元启发式算法

典型油气藏区域环境因素差异对甲烷氧化菌丰度与群落结构分布的影响

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微生物学报 2024年第6期64卷 1992-2007页

作者：许科伟刘海峰顾磊郑旭莹贾仲君陈晟中国石化石油勘探开发研究院无锡石油地质研究所江苏无锡214126 江南大学生物工程学院江苏无锡214122 中国科学院南京土壤研究所江苏南京210008

【目的】甲烷氧化菌(methane-oxidizing bacteria,MOB)是油气微生物勘探中重要的指标微生物,其丰度与群落结构分布受到地理位置和多种环境因素的影响。本研究以采集的7个典型油气藏区域的土壤样品为研究对象,探究油气藏区域环境因素差... 详细信息

【目的】甲烷氧化菌(methane-oxidizing bacteria,MOB)是油气微生物勘探中重要的指标微生物,其丰度与群落结构分布受到地理位置和多种环境因素的影响。本研究以采集的7个典型油气藏区域的土壤样品为研究对象,探究油气藏区域环境因素差异对甲烷氧化菌丰度与群落结构分布的影响。【方法】对采集自7个典型油气藏区域土壤样品进行pmoA基因实时荧光定量PCR(real-time fluorescence quantitative PCR,qPCR)、细菌16S rRNA基因测序和甲烷氧化菌功能基因pmoA测序,结合环境因子,比较甲烷氧化菌丰度差异,分析环境因子对甲烷氧化菌分布的影响。【结果】土壤样品的理化性质测定发现江汉盆地样品的含水量最高,约22.8%,硝态氮平均含量最高位于玉北油田,达到31.96μg/g干重土壤,春光油田出现最高的SO42−(6425.0 mg/g干重土壤)及Cl−(1617.0 mg/g干重土壤)浓度。qPCR分析发现pmoA基因丰度仅为土壤样本总细菌丰度的0.77%,表明甲烷氧化菌绝对数量较少。16S rRNA基因测序发现type I型甲基八叠球菌属(Methylosarcina)、甲基嗜热菌属(Methylocaldum)、甲基球菌属(Methylococcus)与type II型的甲基胞囊菌属(Methylocystis)4种主要的甲烷氧化菌,甲烷氧化菌中的优势菌属的相对丰度极低,最高仅为0.124%。甲烷氧化菌功能基因pmoA测序发现type II型的甲基胞囊菌属、甲基弯曲菌属(Methylosinus)为主要优势pmoA基因型。环境因子与甲烷氧化菌丰度相关性分析表明甲烷氧化菌绝对丰度与铵态氮、pH、颗粒大小、硫酸根和氯离子显著相关,而环境因子与甲烷氧化菌的相对丰度的相关性分析仅发现与颗粒大小、总氮、总磷、金属离子(Al、Fe、K、Ca、Mg、Mn、Zn和Cu)显著相关。甲烷氧化菌pmoA功能基因组成判别相关分析(discriminant correlation analysis,DCA)表明含水量(土壤湿度)、pH值、<2μm的土壤颗粒、总氮及钙离子对甲烷氧化菌pmoA功能基因组成影响具有显著性。【结论】本研究通过对来自7个典型油气藏区域的土壤样品的甲烷氧化菌的绝对丰度与相对丰度进行分析,发现基于不同的测量方法,甲烷氧化菌的丰度存在较大差异,16S rRNA基因测序无法较为全面地反映土壤样本中优势甲烷氧化菌的群落结构,不同地理位置的甲烷氧化菌指示群落存在差异,在全国尺度下油气区及背景点均无特有的甲烷氧化菌指示群落。对环境因子与甲烷氧化菌相关性分析发现,基于不同的甲烷氧化菌丰度指标,环境因子的显著影响具有较大差别。

关键词：微生物勘探高通量测序分子诊断甲烷氧化菌环境因子

NUMERICAL SIMULATION FOR MEASURING YIELD STRENGTH OF THIN METAL FILM BY NANOINDENTATION METHOD

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中国有色金属学会会刊：英文版 1997年第3期7卷 66-69页

作者： Ma, Dejun xu, kewei He, Jiawen Xi'an Jiaotong Univ Xi'an China

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关键词： nanoindentation method thin metal film mechanical properties finite element method

Structural and electronic properties of atomic oxygen adsorption on Cu(111) surface:A first-principles investigation

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Science China(Physics,Mechanics & Astronomy) 2013年第3期56卷 573-580页

作者： MA LiangCai ZHANG JianMin xu kewei College of Physics and Information Technology Shaanxi Normal University School of Physics and Electrical Information Engineering Ningxia University State Key Laboratory for Mechanical Behavior of Materials Xi'an Jiaotong University

By using the first-principles calculations,we have systematically investigated the adsorption of atomic oxygen on Cu(111) surface for a wide range of coverages Θ(from 0.11 to 1.00 ML) and adsorption *** found that the fcc-hollow site is the most stable site for oxygen *** adsorption energy decreases with increasing oxygen coverage due to the increasing repulsive interaction in the overlayer O *** for coverage of 1.00 ML,the oxygen-induced lateral relaxations and bucklings are found in the outermost three Cu layers,and the hillock-like as well as ridge-like bucklings are also found for Θ=0.25 ML and Θ=0.75 ML as well as Θ=0.50 ML,*** an increasing oxygen coverage,the work function increases and the surface dipole moment *** transfer from the first layer Cu atoms to O adatoms indicates the O-Cu bond having some degree of ionic character,while the hybridization between O 2p and Cu 3d orbitals implies that it also has some degree of covalence ***,with the increasing oxygen coverage,more Cu 3d and O 2p states are empty thus weakening the binding of O/Cu(111) system,but increase in the PDOS at the Fermi *** implies an enhancement in the metallic character of the O/Cu(111) system.

关键词： adsorption oxygen relaxation electronic structures first-principles calculation

The structural,electronic and magnetic properties of the 3d TM(V,Cr,Mn,Fe,Co,Ni and Cu) doped ZnO nanotubes:A first-principles study

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Science China(Physics,Mechanics & Astronomy) 2012年第3期55卷 428-435页

作者： ZHANG JianMin GAO Dan xu kewei College of Physics and Information Technology Shaanxi Normal UniversityXi’an 710062China Department of Physics Xi’an University of Arts and ScienceXi’an 710065China

We have performed the first-principles calculations onto the structural,electronic and magnetic properties of seven 3d transition-metal(TM=V,Cr,Mn,Fe,Co,Ni and Cu) atom substituting cation Zn in both zigzag(10,0) and armchair(6,6) zinc oxide nanotubes(ZnONTs).The results show that there exists a structural distortion around 3d TM impurities with respect to the pristine *** magnetic moment increases for V-,Cr-doped ZnONTs and reaches maximum for Mn-doped ZnONTs,and then decreases for Fe-,Co-,Ni-and Cu-doped ZnONTs successively,which is consistent with the predicted trend of Hund's rule for maximizing the magnetic moments of the doped TM ***,the values of the magnetic moments are smaller than the predicted values of Hund's rule due to strong hybridization between p orbitals of the nearest neighbor O atoms of ZnONTs and d orbitals of the TM ***,the Mn-,Fe-,Co-,Cu-doped(10,0) and(6,6) ZnONTs with half-metal and thus 100% spin polarization characters seem to be good candidates for spintronic applications.

关键词： ZnO nanotubes transition-metal atoms dilute magnetic semiconductors first-principles

Structural and electronic properties of chiral single-wall copper nanotubes

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Science China(Physics,Mechanics & Astronomy) 2014年第4期57卷 644-651页

作者： DUAN YingNi ZHANG JianMin xu kewei College of Physics and Information Technology Shaanxi Normal University Department of Medical Engineering and Technology Xinjiang Medical University College of Physics and Mechanical and Electronic Engineering Xi'an University of Arts and Science

The structural,energetic and electronic properties of chiral(n,m)(3≤n≤6,n/2≤m≤n)single-wall copper nanotubes(CuNTs)have been investigated by using projector-augmented wave method based on density-functional ***(4,3)CuNT is energetically stable and should be observed experimentally in both free-standing and tip-suspended conditions,whereas the(5,5)and(6,4)CuNTs should be observed in free-standing and tip-suspended conditions,*** number of conductance channels in the CuNTs does not always correspond to the number of atomic strands comprising the *** density contours show that there is an enhanced interatomic interaction in CuNTs compared with Cu *** transporting states display different periods and chirality,the combined effects of which lead to weaker chiral currents on CuNTs.

关键词： density-functional theory Cu nanotube structural property electronic property

Modulation of the electronic and magnetic properties of a GaN nanoribbon from dangling bonds

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Science China(Physics,Mechanics & Astronomy) 2012年第4期55卷 631-638页

作者： ZHANG JoanMin SUN ChunFeng xu kewei College of Physics andlnformation Technology Shaanxi Normal UniversityXi'an 710062China Department of Physics Xi'an University of Arts and ScienceXi'an 710065China

Though GaN nanoribbons （GaNNRs） with H atoms terminating both edges are nonmagnetic semiconductors, the extra dangling bond bands around the Fermi level lead to a transition from semiconducting to metallic, except for the armchair edge GaNNRs （AGaNNRs） with bare N and Ga edges, which are still nonmagnetic semiconductors due to the strong coupling of the dangling bonds of dimeric N and Ga atoms at the same edge. The larger difference in the charge density （pUp_pdown） for edge bare N atoms and decaying for N sub-lattices away from the edge, as well as the smaller difference in the charge density for edge bare Ga atoms and without decaying for Ga sub-lattices away from the edge is consistent with the magnetic moment of a GaNNR with bare N edge being larger than that of a GaNNR with bare Ga edge. The magnetic moment of a zigzag edge GaNNR （ZGaNNR） with bare N （Ga） edge has nearly half the value of the magnetic moment of a AGaNNR with bare N （Ga） edge. Such a relationship also exists in the number of extra dangling bond states appearing around the Fermi level in the band structures. For ZGaNNRs, the magnetic moment of bare N and Ga edges is larger than either bare N edge or bare Ga edge, but smaller than their sum, implying that there exists an interaction between the dangling bonds at both edges of bare N and Ga edges.

关键词： GaN nanoribbon dangling bond electronic properties magnetic properties first-principles

First-principles study of the adsorption of oxygen atoms on copper nanowires

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Science China(Physics,Mechanics & Astronomy) 2012年第3期55卷 413-418页

作者： MA LiangCai ZHANG JianMin xu kewei College of Physics and Information Technology Shaanxi Normal UniversityXi’an 710062China School of Physics and Electrical Information Engineering Ningxia UniversityYinchuan 750021China Department of Physics Xi’an University of Arts and ScienceXi’an 710065China

By using first-principles calculations,we have systematically investigated the structural stability and electronic properties of a single oxygen atom adsorbed on the surface of foursquare Cu nanowires for a wide range of adsorption *** view of binding energy maximization,we found that the long bridge site at the edge of the Cu nanowires is the most stable site for oxygen adsorption,which is always slightly energetically favorable compared with the hollow site at the *** electron transferring from Cu atoms to O adatom and a significant polarization indicate the O-Cu chemical bond,showing some degree of ionic *** addition,the hybridization between O-2p and Cu-3d states implies the O-Cu bond which also shows some degree of covalence *** main factors which affect the oxygen preferred adsorption site are analyzed from the local geometrical configurations and electronic properties.

关键词： copper nanowire oxygen adsorption first-principles calculation

Numerical study on two-phase flow in horizontal pipe

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排灌机械工程学报 2021年第4期39卷 379-385,425页

作者： WU Yuting xu kewei KIM Hyoungbum School of Mechanical and Aerospace Engineering Gyeongsang National UniversityJinju 52828S.Korea Research Center for Aircraft Parts Technology Gyeongsang National UniversityJinju 52828S.Korea

Two-phase flow in a horizontal pipe was investigated by using numerical and experimental visualization methods.A horizontal pipe was built for qualitative and quantitative flow *** length of horizontal pipe flow system was 9.5 m and the inner diameter was 51 ***-speed video method was used for the qualitative visualization and PIV method was applied for the quantitative *** same geometry model was used for the numerical *** flow regimes including stratified flow,elongated bubble and slug flow field were generated and visualized by using numerical and experimental *** results show that the numerical simulation results are qualitatively si-milar to that of the experimental *** addition,more quantitative results can be analyzed by numerical *** and decay process of slug flow was investigated,showing that the decay of slug heavily depends on the magnitude of nose velocity and its lasting *** can also be found that the liquid superficial velocity plays a significant role in affecting the slug *** keeping the gas superficial velocity constant,the frequency will increase with the liquid superficial velocity.

关键词： two-phase flow CFD PIV slug flow slug frequency