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期刊论文 38

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S-N曲线 1

SOFC 1

TBM 隧洞 1

三维激发极化法 1

不良地质体 1

中轴变换；包络；插值；蒙皮；圆 1

交流阻抗 1

偏振模色散（PMD） 1

反射阵；双极化；赋形波束；限相位综合 1

可重构天线 1

固体氧化物材料 1

地质分析 1

地震法 1

大数据 1

归零码（RZ） 1

智能计算量分配；轨迹规划；公路规划；智能汽车；序优化 1

极化可编程天线 1

树脂灌注式螺栓 1

环形天线；宽带天线；极化分集；方向图分集 1

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The effect of pH, solid content, water chemistry and ore mineralogy on the galvanic interactions between chalcopyrite and pyrite and steel balls

Asghar Azizi, Seid Ziaoddin Shafaei, Mohammad Noaparast, Mohammad Karamoozian

《化学科学与工程前沿（英文）》 2013年 第7卷 第4期   页码 464-471 doi: 10.1007/s11705-013-1356-z

摘要： The role of pH, solid content, water chemistry and ore mineralogy on the galvanic interactions between chalcopyrite and pyrite and low alloy steel balls were investigated in the grinding of Sarcheshmeh porphyry copper sulfide ore. All these factors strongly affect the galvanic current between the minerals and the steel during the grinding process. The galvanic current density decreased as the solution pH and percent solids increased. In addition, changing the water in the ball mill from tap to distilled water reduced the galvanic current between the minerals and the balls. Potentiodynamic polarization curves showed that pyrite and chalcopyrite demonstrated typical active-passive-transpassive anodic behavior in the grinding of copper ore. However, the nature of their transitions from the active to the passive state differed. This behavior was not seen in the grinding of pure minerals. In addition, an EDTA extraction technique was employed to quantify the amount of oxidized iron in the mill discharge. The amount of extractable iron was influenced by the same experimental factors and in the same way as the galvanic current.

关键词： steel ball     galvanic interaction     pyrite     chalcopyrite     polarization curves    

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Development of realistic design fire time-temperature curves for the testing of cold-formed steel wall

Anthony Deloge ARIYANAYAGAM,Mahen MAHENDRAN

《结构与土木工程前沿（英文）》 2014年 第8卷 第4期   页码 427-447 doi: 10.1007/s11709-014-0279-1

摘要： Fire resistance rating of light gauge steel frame (LSF) wall systems is obtained from fire tests based on the standard fire time-temperature curve. However, fire severity has increased in modern buildings due to higher fuel loads as a result of modern furniture and light weight constructions that make use of thermoplastics materials, synthetic foams and fabrics. Some of these materials are high in calorific values and increase both the spread of fire growth and heat release rate, thus increasing the fire severity beyond that of the standard fire curve. Further, the standard fire curve does not include a decay phase that is present in natural fires. Despite the increasing usage of LSF walls, their behavior in real building fires is not fully understood. This paper presents the details of a research study aimed at developing realistic design fire curves for use in the fire tests of LSF walls. It includes a review of the characteristics of building fires, previously developed fire time-temperature curves, computer models and available parametric equations. The paper highlights that real building fire time-temperature curves depend on the fuel load representing the combustible building contents, ventilation openings and thermal properties of wall lining materials, and provides suitable values of many required parameters including fuel loads in residential buildings. Finally, realistic design fire time-temperature curves simulating the fire conditions in modern residential buildings are proposed for the testing of LSF walls.

关键词： fire safety     standard fire curve     realistic design fire time-temperature curves     light gauge steel frame (LSF) walls     fire resistance rating     fuel load    

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Erratum to: Meter-scale variation within a single transect demands attention to taxon accumulation curves

《环境科学与工程前沿（英文）》 2022年 第16卷 第6期 doi: 10.1007/s11783-022-1560-5

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Spin polarization strategy to deploy proton resource over atomic-level metal sites for highly selective

《化学科学与工程前沿（英文）》 2022年 第16卷 第12期   页码 1772-1781 doi: 10.1007/s11705-022-2197-4

摘要： Unlocking of the extremely inert C=O bond during electrochemical CO2 reduction demands subtle regulation on a key “resource”, protons, necessary for intermediate conversion but also readily trapped in water splitting, which is still challenging for developing efficient single-atom catalysts limited by their structural simplicity usually incompetent to handle this task. Incorporation of extra functional units should be viable. Herein, a proton deployment strategy is demonstrated via “atomic and nanostructured iron (A/N-Fe) pairs”, comprising atomically dispersed iron active centers spin-polarized by nanostructured iron carbide ferromagnets, to boost the critical protonation steps. The as-designed catalyst displays a broad window (300 mV) for CO selectivity > 90% (98% maximum), even outperforming numerous cutting-edge M–N–C systems. The well-placed control of proton dynamics by A/N-Fe can promote *COOH/*CO formation and simultaneously suppress H2 evolution, benefiting from the magnetic-proximity-induced exchange splitting (spin polarization) that properly adjusts energy levels of the Fe sites’ d-shells, and further those of the adsorbed intermediates’ antibonding molecular orbitals.

关键词： CO2 electrolysis     single-atom catalysts     spin polarization     proton dynamics     in situ IR spectroscopy     kinetic isotope effect    

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Meter-scale variation within a single transect demands attention to taxon accumulation curves in riverine

《环境科学与工程前沿（英文）》 2022年 第16卷 第5期 doi: 10.1007/s11783-022-1543-6

摘要：

● Riverine microbiomes exhibited hyperlocal variation within a single transect.

关键词： Microbiome     Freshwater     Taxon accumulation curve     Community assembly    

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Damage-constitutive model for seawater coral concrete using different stirrup confinements subjected to axial loading

《结构与土木工程前沿（英文）》 2023年 第17卷 第3期   页码 429-447 doi: 10.1007/s11709-022-0913-2

摘要： Recently, the application of detrital coral as an alternative to natural aggregates in marine structures has attracted increased attention. In this study, research on the compressive performance of coral aggregate concrete (CAC) confined using steel stirrups with anti-rust treatment was experimentally conducted. A total of 45 specimens were cast, including 9 specimens without stirrups and under different strength grades (C20, C30, and C40) and 36 specimens under different strength grades (C20, C30, and C40). Moreover, three stirrup levels (rectangular, diamond-shaped compound, and spiral stirrups) and different stirrup spacings (40, 50, 60, and 70 mm) were used. Subsequently, the stress−strain curves of specimens subjected to axial loading were measured. The effects of the stirrup spacing and stirrup configurations on the stress and strain were investigated, respectively, and the lateral effective stress of the different stirrups was calculated based on the cohesive-elastic ring model and modified elastic beam theory. Moreover, a damage-constitutive model of CAC considering the lateral stress was set up based on damage mechanics theory. The results indicated an increase in the stress and strain with a decrease in the stirrup spacing, and the adopted stirrup ratio had a better strengthening effect than the different concrete grades, and the variation in the deformation was restricted by the performance of coral coarse aggregate (CA). However, an increment in the lateral strain was observed with an increase in the axial strain. The lateral stress model showed a good agreement with the experimental data, and the proposed damage-constitutive model had a good correlation with the measured stress−strain curves.

关键词： coral aggregate concrete     stress−strain curves     lateral effective stress     peak stress     axial−lateral curves     damage-constitutive model.    

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Stress induced polarization switching and coupled hysteretic dynamics in ferroelectric materials

Linxiang WANG, Roderick MELNIK, Fuzai LV

《机械工程前沿（英文）》 2011年 第6卷 第3期   页码 287-291 doi: 10.1007/s11465-011-0230-2

摘要：

The dynamic responses of ferroelectric materials upon external mechanical and electrical stimulations are inherently nonlinear and coupled. In the current paper, a macroscopic differential model is constructed for the coupled hysteretic dynamics via modeling the orientation switching induced in the materials. A non-convex potential energy is constructed with both mechanic and electric field contributions. The governing equations are formulated as nonlinear ordinary differential equations by employing the Euler-Lagrange equation, and can be easily recast into a state space form. Hysteresis loops associated with stress induced polarization switching and butterfly-shaped behavior in ferroelectric materials are also successfully captured. The effects of mechanical loadings on the electrically induced switching are numerically investigated, as well as the mechanically-induced switching with various bias electric fields.

关键词： differential model     state space     electromechanical switching     butterfly effects     hysteresis    

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Seismic fragility curves for structures using non-parametric representations

Chu MAI, Katerina KONAKLI, Bruno SUDRET

《结构与土木工程前沿（英文）》 2017年 第11卷 第2期   页码 169-186 doi: 10.1007/s11709-017-0385-y

摘要： Fragility curves are commonly used in civil engineering to assess the vulnerability of structures to earthquakes. The probability of failure associated with a prescribed criterion (e.g., the maximal inter-storey drift of a building exceeding a certain threshold) is represented as a function of the intensity of the earthquake ground motion (e.g., peak ground acceleration or spectral acceleration). The classical approach relies on assuming a lognormal shape of the fragility curves; it is thus parametric. In this paper, we introduce two non-parametric approaches to establish the fragility curves without employing the above assumption, namely binned Monte Carlo simulation and kernel density estimation. As an illustration, we compute the fragility curves for a three-storey steel frame using a large number of synthetic ground motions. The curves obtained with the non-parametric approaches are compared with respective curves based on the lognormal assumption. A similar comparison is presented for a case when a limited number of recorded ground motions is available. It is found that the accuracy of the lognormal curves depends on the ground motion intensity measure, the failure criterion and most importantly, on the employed method for estimating the parameters of the lognormal shape.

关键词： earthquake engineering     fragility curves     lognormal assumption     non-parametric approach     kernel density estimation     epistemic uncertainty    

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Dynamic modulation performance of ferroelectric liquid crystal polarization rotators and Mueller matrix

Song ZHANG, Lelun WANG, Anze YI, Honggang GU, Xiuguo CHEN, Hao JIANG, Shiyuan LIU

《机械工程前沿（英文）》 2020年 第15卷 第2期   页码 256-264 doi: 10.1007/s11465-019-0573-7

摘要： A ferroelectric liquid crystal polarization rotator (FLCPR) has been widely used in polarization measurement due to its fast and stable modulation characteristics. The accurate characterization of the modulation performance of FLCPR directly affects the measurement accuracy of the instrument based on liquid crystal modulation. In this study, FLCPR is accurately characterized using a self-developed high-speed Stokes polarimeter. Strong linear and weak circular birefringence are observed during modulation processes, and all the optical parameters of FLCPR are dependent on driving voltage. A dual FLCPR-based Mueller matrix polarimeter is designed on the basis of the Stokes polarimeter. The designed polarimeter combines the advantages of the high modulation frequency of FLCPR and the ultrahigh temporal resolution of the fast polarization measurement system in the Stokes polarimeter. The optimal configuration of the designed polarizer is predicted in accordance with singular value decomposition. A simulated thickness measurement of a 24 nm standard SiO thin film is performed using the optimal configuration. Results show that the relative error in thickness measurement caused by using the unsatisfactory modulation characteristics of FLCPR reaches up to −4.34%. This finding demonstrates the importance of the accurate characterization of FLCPR in developing a Mueller matrix polarizer.

关键词： ferroelectric liquid crystal polarization rotator (FLCPR)     dual liquid crystal Mueller matrix polarizer     design and optimization    

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Kinetics of enhanced adsorption by polarization for organic pollutants on activated carbon fiber

HAN Yanhe, QUAN Xie, ZHAO Huimin, CHEN Shuo, ZHAO Yazhi

《环境科学与工程前沿（英文）》 2007年 第1卷 第1期   页码 83-88 doi: 10.1007/s11783-007-0016-2

摘要： The adsorption kinetics for model pollutants on activated carbon fiber (ACF) by polarization was investigated in this work. Kinetics data obtained for the adsorption of these model pollutants at open-circuit, 400 mV, and -400 mV polarization were applied to the Lagergren equation, and adsorption rate constants () were determined. With the anodic polarization of 400 mV, the capacity of sodium phenoxide was increased from 0.0083 mmol/g at open-circuit to 0.18 mmol/g, and a 17-fold enhancement was achieved; however, the capacity of -nitrophenol was decreased from 2.93 mmol/g at open-circuit to 2.65 mmol/g. With the cathodal polarization of -400 mV, the capacity of aniline was improved from 3.60 mmol/g at open-circuit to 3.88 mmol/g; however, the capacity of sodium dodecylbenzene sulfonate was reduced from 2.20 mmol/g at open-circuit to 1.59 mmol/g. The enhancement for electrosorption changed with dif ferent groups substituting. Anodic polarization enhances the adsorption of benzene with the electron-donating group. But whether anodic or not, cathodal polarization had less effect on the adsorption of electron-accepting aromatic compounds, and decreased the adsorption capacity of benzene-bearing donor-conjugate bridge-acceptor, while increasing its adsorption rate. Electrostatic interaction played a very important role in the electrosorption of ion-pollutants.

关键词： ACF     activated     17-fold enhancement     donor-conjugate bridge-acceptor     Electrostatic interaction    

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Spontaneous polarization enhanced bismuth ferrate photoelectrode: fabrication and boosted photoelectrochemical

《能源前沿（英文）》 2021年 第15卷 第3期   页码 781-790 doi: 10.1007/s11708-021-0782-8

摘要： In this paper, the fabrication of a highly orientated Bi2Fe4O9 (BFO) photoelectrode in the presence of two-dimensional (2D) graphene oxide (GO) was reported. It was found that the GO can be used as a template for controlling the growth of BFO, and the nanoplate composites of BFO/reduced graphene oxide (RGO) with a high orientation can be fabricated. The thickness of the nanoplates became thinner as the ratio of GO increased. As a result, the ferroelectric spontaneous polarization unit arranges itself in the space in a periodic manner, leading to the formation of a polarization field along a special direction. Therefore, the created built-in electric field of the nanoplate composites of BFO/RGO is improved upon the increase of the amount of RGO. As expected, carrier separation is enhanced by the built-in electric field, therefore substantially enhancing the photoelectrochemical (PEC) activity of water splitting compared to pure BFO under the irradiation of visible-light.

关键词： bismuth ferrate     ferroelectric polarisation     photoelectrochemical (PEC) water splitting     graphene oxide (GO)     high orientation    

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极限工程——产品开发和制造中的极化

Andrew Kusiak

《工程（英文）》 2021年 第7卷 第3期   页码 282-284 doi: 10.1016/j.eng.2020.01.012

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偏振模色散对高速光码的影响

饶敏,孙小菡,张明德

《中国工程科学》 2002年 第4卷 第11期   页码 67-70

摘要：

研究一阶、二阶偏振模色散（PMD）对10 Gb/s和40 Gb/s的光传输系统性能的影响，考虑PMD的统计特性，基于基本偏振态（PSP）理论数值模拟了非归零码（NRZ）和归零码（RZ）在传输过程中产生的脉冲畸变以及系统Q值的变化。结果表明，传输速率越高PMD对系统性能的影响越显著，二阶PMD也将不可忽略。另外，RZ码传输性能明显优于NRZ码并且可通过预啁啾进行改善。

关键词： 偏振模色散（PMD）     非归零码（NRZ）     归零码（RZ）     频率啁啾    

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卫星通信大型双极化中国版图赋形微带反射阵天线的优化设计 Research Articles

Gang ZHAO, Yong-chang JIAO, Guan-tao CHEN

《信息与电子工程前沿（英文）》 2020年 第21卷 第1期   页码 159-173 doi: 10.1631/FITEE.1900496

摘要： 设计了一款具有中国版图赋形的大型双频双极化微带反射阵天线。为充分补偿两个频段范围内的空间相位延迟差，采用一种适用于大型双极化反射阵的3层矩形贴片单元。由于赋形区域形状复杂、赋形增益要求很高，该反射阵天线单元数量超过25 000个，优化变量数超过150 000个，导致其设计非常困难。本文首先通过离散快速傅里叶变换及其逆变换建立口径场和远场的一一对应关系，为赋形反射阵天线的优化奠定基础。进而采用基于交替投影的交集方法，优化获得多个典型频率下所有单元的目标反射相位。为避免优化过程陷入局部极值点，采用一种产生合适初始解的新方法。为验证设计方法的有效性，制作了一个7569单元的双极化反射阵天线并进行实验测试。测试与仿真结果吻合良好。为使宽带工作的大型反射阵天线带宽范围的空间相位延迟极小化，提出一种确定馈源最佳位置的方法。为在两个相互正交方向上同时找到单元的最优尺寸，建立一种新的优化模型，通过正多面体优化方法进行优化计算。最后，设计了一款覆盖中国陆地版图的单元数为25 305的双频双极化微带反射阵天线。仿真结果表明，该反射阵天线在两个工作频带范围内均可满足中国版图覆盖要求，证明所提出的复杂赋形波束大型反射阵天线优化设计方法可靠和有效。

关键词： 反射阵；双极化；赋形波束；限相位综合    

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Long-term effects of electrochemical realkalization on carbonated concrete

Peng ZHU, Ji ZHANG, Wenjun QU

《结构与土木工程前沿（英文）》 2020年 第14卷 第1期   页码 127-137 doi: 10.1007/s11709-019-0583-x

摘要： The long-term effects of electrochemical realkalization on carbonated reinforced concrete with a / ratio of 0.65 were studied. Fourteen out of 16 carbonated specimens had been subjected to realkalization seven years ago, and the alkalinity of the concrete, the electrochemical characters (corrosion current density and potential) of the specimens and the corrosion conditions of the steel bars were examined. Results of different specimens and also at different time (4, 10, 13 months and 7 years after realkalization) were compared. According to the phenolphthalein and pH meter test, the alkalinity of the concrete had disappeared after seven years. Based on the potentiodynamic polarization test, various corrosion conditions had developed on the steel bars, which was verified by visual observation. All bars were in the depassivated state, and their corrosion current densities increased significantly after seven years. Cracks developed in some of the specimens, and the diverse compactness of concrete and excessive current of realkalization were considered to be possible causes. The effects of the realkalization treatment vanished after seven years.

关键词： realkalization     concrete     carbonation     polarization curve     corrosion    

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标题 作者 时间 类型 操作

The effect of pH, solid content, water chemistry and ore mineralogy on the galvanic interactions between chalcopyrite and pyrite and steel balls

Asghar Azizi, Seid Ziaoddin Shafaei, Mohammad Noaparast, Mohammad Karamoozian

期刊论文

Development of realistic design fire time-temperature curves for the testing of cold-formed steel wall

Anthony Deloge ARIYANAYAGAM,Mahen MAHENDRAN

期刊论文

Erratum to: Meter-scale variation within a single transect demands attention to taxon accumulation curves

期刊论文

Spin polarization strategy to deploy proton resource over atomic-level metal sites for highly selective

期刊论文

Meter-scale variation within a single transect demands attention to taxon accumulation curves in riverine

期刊论文

Damage-constitutive model for seawater coral concrete using different stirrup confinements subjected to axial loading

期刊论文

Stress induced polarization switching and coupled hysteretic dynamics in ferroelectric materials

Linxiang WANG, Roderick MELNIK, Fuzai LV

期刊论文

Seismic fragility curves for structures using non-parametric representations

Chu MAI, Katerina KONAKLI, Bruno SUDRET

期刊论文

Dynamic modulation performance of ferroelectric liquid crystal polarization rotators and Mueller matrix

Song ZHANG, Lelun WANG, Anze YI, Honggang GU, Xiuguo CHEN, Hao JIANG, Shiyuan LIU

期刊论文

Kinetics of enhanced adsorption by polarization for organic pollutants on activated carbon fiber

HAN Yanhe, QUAN Xie, ZHAO Huimin, CHEN Shuo, ZHAO Yazhi

期刊论文

Spontaneous polarization enhanced bismuth ferrate photoelectrode: fabrication and boosted photoelectrochemical

期刊论文

极限工程——产品开发和制造中的极化

Andrew Kusiak

期刊论文

偏振模色散对高速光码的影响

饶敏,孙小菡,张明德

期刊论文

卫星通信大型双极化中国版图赋形微带反射阵天线的优化设计

Gang ZHAO, Yong-chang JIAO, Guan-tao CHEN

期刊论文

Long-term effects of electrochemical realkalization on carbonated concrete

Peng ZHU, Ji ZHANG, Wenjun QU

期刊论文