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Fabrication and performance of PEN SOFCs with proton-conducting electrolyte

ZHONG Li, LUO Jingli, Karl Chuang

《化学科学与工程前沿（英文）》 2007年 第1卷 第1期   页码 40-44 doi: 10.1007/s11705-007-0008-6

摘要： A positive-electrolyte-negative (PEN) assembly solid oxide fuel cell (SOFC) with a thin electrolyte film for intermediate temperature operation was fabricated. Instead of the traditional screen-printing method, both anode and cathode catalysts were pressed simultaneously and formed with the fabrication of nano-composite electrolyte by press method. This design offered some advantageous configurations that diminished ohmic resistance between electrolyte and electrodes. It also increased the proton-conducting rate and improved the performance of SOFC due to the reduction of membrane thickness and good contact between electrolyte and electrodes. The fabricated PEN cell generated electricity between 600?C and 680?C using HS as fuel feed and air as oxidant. Maximum power densities 40 mW " cm and 130 mW " cm for the PEN configuration with a Mo-Ni-S-based composite anode, nano-composite electrolyte (LiSO+AlO) film and a NiO-based composite cathode were achieved at 600?C and 680?C, respectively.

关键词： proton-conducting     positive-electrolyte-negative     temperature operation     Mo-Ni-S-based composite     advantageous    

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The Immense Impact of Reverse Edges on Large Hierarchical Networks

Haosen Cao,Bin-Bin Hu,Xiaoyu Mo,Duxin Chen,Jianxi Gao,Ye Yuan,Guanrong Chen,Tamás Vicsek,Xiaohong Guan

《工程（英文）》 doi: 10.1016/j.eng.2023.06.011

摘要： Hierarchical networks are frequently encountered in animal groups, gene networks, and artificial engineering systems such as multiple robots, unmanned vehicle systems, smart grids, wind farm networks, and so forth. The structure of a large directed hierarchical network is often strongly influenced by reverse edges from lower- to higher- level nodes, such as lagging birds’ howl in a flock or the opinions of lower-level individuals feeding back to higher-level ones in a social group. This study reveals that, for most large-scale real hierarchical networks, the majority of the reverse edges do not affect the synchronization process of the entire network; the synchronization process is influenced only by a small part of these reverse edges along specific paths. More surprisingly, a single effective reverse edge can slow down the synchronization of a huge hierarchical network by over 60%. The effect of such edges depends not on the network size but only on the average in-degree of the involved subnetwork. The overwhelming majority of active reverse edges turn out to have some kind of “bunching” effect on the information flows of hierarchical networks, which slows down synchronization processes. This finding refines the current understanding of the role of reverse edges in many natural, social, and engineering hierarchical networks, which might be beneficial for precisely tuning the synchronization rhythms of these networks. Our study also proposes an effective way to attack a hierarchical network by adding a malicious reverse edge to it and provides some guidance for protecting a network by screening out the specific small proportion of vulnerable nodes.

关键词： Synchronizability     Large hierarchical networks     Reverse edges     Information flows     Complex networks    

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Ni-Co bimetallic catalyst for CH

Xiaohong LI, Jun AI, Wenying LI, Dongxiong LI

《化学科学与工程前沿（英文）》 2010年 第4卷 第4期   页码 476-480 doi: 10.1007/s11705-010-0512-y

摘要： A co-precipitation method was employed to prepare Ni/Al O -ZrO , Co/Al O -ZrO and Ni-Co/Al O -ZrO catalysts. Their properties were characterized by N adsorption (BET), thermogravimetric analysis TGA , temperature-programmed reduction (TPR), temperature-programmed desorption (CO -TPD), and temperature-programmed surface reaction (CH -TPSR and CO -TPSR). Ni-Co/Al O -ZrO bimetallic catalyst has good performance in the reduction of active components Ni, Co and CO adsorption. Compared with mono-metallic catalyst, bimetallic catalyst could provide more active sites and CO adsorption sites (C+ CO = 2CO) for the methane-reforming reaction, and a more appropriate force formed between active components and composite support (SMSI) for the catalytic reaction. According to the CH -CO -TPSR, there were 80.9% and 81.5% higher CH and CO conversion over Ni-Co/Al O -ZrO catalyst, and its better resistance to carbon deposition, less than 0.5% of coke after 4 h reaction, was found by TGA. The high activity and excellent anti-coking of the Ni-Co/Al O -ZrO catalyst were closely related to the synergy between Ni and Co active metal, the strong metal-support interaction and the use of composite support.

关键词： Ni-Co bimetallic catalyst     composite support     CH4 reforming with CO2    

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or insufficient: Assessment of the intended nationally determined contributions (INDCs) of the world’s

Ge GAO, Mo CHEN, Jiayu WANG, Kexin YANG, Yujiao XIAN, Xunpeng SHI, Ke WANG

《工程管理前沿（英文）》 2019年 第6卷 第1期   页码 19-37 doi: 10.1007/s42524-019-0007-6

摘要：

The recent Conference of the Parties of the United Nations Framework Convention on Climate Change has resulted in the submission of the Intended Nationally Determined Contributions (INDCs) of 190 countries. This study aims to provide an analysis of the ambitiousness and fairness of the mitigation components of the INDCs submitted by various parties. We use a unified framework to assess 23 INDCs that cover 50 countries, including European Union (EU)-28 countries as parties to the Convention, which represent 87.45% of the global greenhouse gas emissions in 2012. First, we transform initial INDC files into reported reduction targets. Second, we create four schemes and six scenarios to determine the required reduction effort, which considers each nation’s reduction responsibility, capacity, and potential, thereby reflecting their historical and current development status. Finally, we combine the reported reduction target and the required reduction effort to assess INDCs. Evaluation results of the 23 emitters indicate that 2 emitters (i.e., EU and Brazil) are rated as “sufficient,” 7 emitters (e.g., China, the United States, and Canada) are rated as “moderate,” and 14 emitters (e.g., India, Russia, and Japan) are rated as “insufficient.” Most pledges exhibit a considerable distance from representing a fair contribution.

关键词： Intended Nationally Determined Contributions     mitigation     responsibility     capacity     potential    

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Estimation of relations among hysteretic response measures and design parameters for RC rectangular shear walls

BANAN, Mo. R. BANAN, S. FARHADI

《结构与土木工程前沿（英文）》 2018年 第12卷 第1期   页码 3-15 doi: 10.1007/s11709-017-0418-6

摘要： Seismic design of RC structures requires estimation of structural member behavioral measures as functions of design parameters. In this study, the relations among cyclic behavioral measures and design parameters have been investigated for rectangular RC shear walls using numerical simulations calibrated based on the published laboratory tests. The OpenSEES numerical simulations modeling of plastic hinge hysteretic behavior of RC shear walls and estimation of empirical relations among wall hysteretic indices and design parameters are presented. The principal design parameters considered were wall dimensions, axial force, reinforcement ratios, and end-element design parameters. The estimated hysteretic response measures are wall effective stiffness, yield and ultimate curvatures, plastic moment capacity, yield and ultimate displacements, flexural shear capacity, and dissipated energy. Using results of numerous analyses, the empirical relations among wall cyclic behavioral measures and design parameters are developed and their accuracy is investigated.

关键词： RC wall hysteretic measures     RC wall design parameters     empirical relations     numerical simulations     RC rectangular wall plastic hinge    

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用于复合材料结构生产的编织增强材料树脂灌注工艺模拟

Robert S. Pierce, Brian G. Falzon

《工程（英文）》 2017年 第3卷 第5期   页码 596-607 doi: 10.1016/J.ENG.2017.04.006

摘要：

商用飞机对减轻机身重量和提高燃料效率的需求日益增强，这一需求促进了复合材料在商用飞机结构中的应用。当飞机的复合材料结构变得更庞大、更复杂时，传统的热压罐生产方法就会变得相当昂贵，这一现象引起了研究者对非热压罐成型技术的关注。在此技术中，树脂被注入强化预浸料层。然而，树脂灌注工艺与操作人员的技术和经验息息相关，特别是在开发复杂部件的生产策略时。作为一种用于预测的计算工具，流程建模旨在解决可靠性问题以及传统反复试验法所导致的浪费。大多数传统建模仍应用于工业，主要针对各向同性多孔强化材料的流体流动模拟。然而，最近的一些研究开始将编织材料的多尺度和多学科的复杂性纳入考虑范畴，其模拟方法可以提供更高的保真度。尤其考虑到具有渗透性和多孔性的强化材料导致的织物变形效应，新的多物理场流程模拟能够通过织物更好地预测树脂的灌注行为。除了综述与流程模拟相关的前人研究和工艺现状，本文还重点论述了最近关于复杂双圆顶组件的多物理场流程模拟与实验灌注的对比验证。通过考虑变形依赖的流动行为，多物理场流程模拟能够预测实际的流动行为，证明其与基础的各向同性渗透模型相比有很大程度的改进。

关键词： 复合材料     编织增强     悬垂     灌注     数值模拟    

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Application of consistent geometric decomposition theorem to dynamic finite element of 3D composite beambased on experimental and numerical analyses

Iman FATTAHI, Hamid Reza MIRDAMADI, Hamid ABDOLLAHI

《结构与土木工程前沿（英文）》 2020年 第14卷 第3期   页码 675-689 doi: 10.1007/s11709-020-0625-4

摘要： Analyzing static and dynamic problems including composite structures has been of high significance in research efforts and industrial applications. In this article, equivalent single layer approach is utilized for dynamic finite element procedures of 3D composite beam as the building block of numerous composite structures. In this model, both displacement and strain fields are decomposed into cross-sectional and longitudinal components, called consistent geometric decomposition theorem. Then, the model is discretized using finite element procedures. Two local coordinate systems and a global one are defined to decouple mechanical degrees of freedom. Furthermore, from the viewpoint of consistent geometric decomposition theorem, the transformation and element mass matrices for those systems are introduced here for the first time. The same decomposition idea can be used for developing element stiffness matrix. Finally, comprehensive validations are conducted for the theory against experimental and numerical results in two case studies and for various conditions.

关键词： composite beam     dynamic finite element     degrees of freedom coupling     experimental validation     numerical validation    

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钢箱-混凝土组合梁正截面强度设计理论与试验研究

钟新谷,舒小娟,沈明燕,莫时旭,谢文

《中国工程科学》 2008年 第10卷 第10期   页码 47-53

摘要：

基于钢箱-混凝土组合梁的基本特性，提出了正截面强度设计理论，并分析梁宽厚比、混凝土套箍效应对正截面强度的影响，提出了该类组合截面的合理尺寸选择原则，分析表明钢箱-混凝土组合梁较空箱的承载力有明显提高，其受力性能明显改善。同时进行3根大比例钢箱-混凝土组合梁的模型试验研究，试验研究表明：钢箱-混凝土组合梁具有良好的抗弯性能和延性，极限承载力提高显著。钢箱-混凝土组合梁通过进一步的试验与理论研究有广泛的应用前景。

关键词： 钢箱-混凝土组合梁     设计理论     试验研究    

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Effect of a promoter on the methanation activity of a Mo-based sulfur-resistant catalyst

Can LIN, Haiyang WANG, Zhenhua LI, Baowei WANG, Xinbin MA, Shaodong QIN, Qi SUN

《化学科学与工程前沿（英文）》 2013年 第7卷 第1期   页码 88-94 doi: 10.1007/s11705-013-1301-1

摘要： The effect of adding Co, Ni or La on the methanation activity of a Mo-based sulfur-resistant catalyst was investigated. As promoters, Co, Ni and La all improved the methanation activity of a 15% MoO /Al O catalyst but to different extents. Similar improvements were also found when Co, Ni or La was added to a 15% MoO /25%-CeO -Al O catalyst. The promotion effects of Co and Ni were better than that of La. However, the catalytic methanation activity deteriorated the most with time for the Ni-promoted catalyst. The used catalysts were analyzed by nitrogen adsorption measurement, X-ray diffraction and X-ray photoelectron spectroscopy.

关键词： sulfur-resistant     methanation     promoter    

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Corrosion behavior of Fe–Cr–Ni based alloys exposed to molten MgCl2–KCl–NaCl salt with over-added

《化学科学与工程前沿（英文）》 2023年 第17卷 第10期   页码 1608-1619 doi: 10.1007/s11705-023-2349-1

摘要： MgCl2–NaCl–KCl salts mixture shows great potential as a high-temperature (> 700 °C) thermal energy storage material in next-generation concentrated solar power plants. Adding Mg into molten MgCl2–NaCl–KCl salt as a corrosion inhibitor is one of the most effective and cost-effective methods to mitigate the molten salt corrosion of commercial Fe–Cr–Ni alloys. However, it is found in this work that both stainless steel 310 and Incoloy 800H samples were severely corroded after 500 h immersion test at 700 °C when the alloy samples directly contacted with the over-added Mg in the liquid form. The corrosion attack is different from the classical impurity-driven corrosion in molten chloride salts found in previous work. Microscopic analysis indicates that Ni preferentially leaches out of alloy matrix due to the tendency to form MgNi2/Mg2Ni compounds. The Ni-depletion leads to the formation of a porous corrosion layer on both alloys, with the thickness around 204 µm (stainless steel 310) and 1300 µm (Incoloy 800H), respectively. These results suggest that direct contact of liquid Mg with Ni-containing alloys should be avoided during using Mg as a corrosion inhibitor for MgCl2–NaCl–KCl or other chlorides for high temperature heat storage and transfer.

关键词： concentrated solar power (CSP)     Mg corrosion inhibitor     Mg–Ni intermetallic     salt purification     thermal energy storage (TES)    

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Uncertainty propagation in dynamics of composite plates: A semi-analytical non-sampling-based approach

Mahdi FAKOOR, Hadi PARVIZ

《结构与土木工程前沿（英文）》 2020年 第14卷 第6期   页码 1359-1371 doi: 10.1007/s11709-020-0658-8

摘要： In this study, the influences of spatially varying stochastic properties on free vibration analysis of composite plates were investigated via development of a new approach named the deterministic-stochastic Galerkin-based semi-analytical method. The material properties including tensile modulus, shear modulus, and density of the plate were assumed to be spatially varying and uncertain. Gaussian fields with first-order Markov kernels were utilized to define the aforementioned material properties. The stochastic fields were decomposed via application of the Karhunen-Loeve theorem. A first-order shear deformation theory was assumed, following which the displacement field was defined using admissible trigonometric modes to derive the potential and kinetic energies. The stochastic equations of motion of the plate were obtained using the variational principle. The deterministic-stochastic Galerkin-based method was utilized to find the probability space of natural frequencies, and the corresponding mode shapes of the plate were determined using a polynomial chaos approach. The proposed method significantly reduced the size of the mathematical models of the structure, which is very useful for enhancing the computational efficiency of stochastic simulations. The methodology was verified using a stochastic finite element method and the available results in literature. The sensitivity of natural frequencies and corresponding mode shapes due to the uncertainty of material properties was investigated, and the results indicated that the higher-order modes are more sensitive to uncertainty propagation in spatially varying properties.

关键词： composite plate     spatially varying stochastic properties     Galerkin method     polynomial chaos approach     semi-analytical approach    

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Performance of soft-hard-soft (SHS) cement based composite subjected to blast loading with consideration

Jun WU,Xuemei LIU

《结构与土木工程前沿（英文）》 2015年 第9卷 第3期   页码 323-340 doi: 10.1007/s11709-015-0301-2

摘要： This paper presents a combined experimental and numerical study on the damage and performance of a soft-hard-soft (SHS) multi-layer cement based composite subjected to blast loading which can be used for protective structures and infrastructures to resist extreme loadings, and the composite consists of three layers of construction materials including asphalt concrete (AC) on the top, high strength concrete (HSC) in the middle, and engineered cementitious composites (ECC) at the bottom. To better characterize the material properties under dynamic loading, interface properties of the composite were investigated through direct shear test and also used to validate the interface model. Strain rate effects of the asphalt concrete were also studied and both compressive and tensile dynamic increase factor (DIF) curves were improved based on split Hopkinson pressure bar (SHPB) test. A full-scale field blast test investigated the blast behavior of the composite materials. The numerical model was established by taking into account the strain rate effect of all concrete materials. Furthermore, the interface properties were also considered into the model. The numerical simulation using nonlinear finite element software LS-DYNA agrees closely with the experimental data. Both the numerical and field blast test indicated that the SHS composite exhibited high resistance against blast loading.

关键词： high strength concrete (SHS)     engineered cementitious composite     interface     blast test     strain rate effect    

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Nano-copper ions assembled cellulose-based composite with antibacterial activity for biodegradable personal

《化学科学与工程前沿（英文）》 2023年 第17卷 第10期   页码 1544-1554 doi: 10.1007/s11705-022-2288-2

摘要： The current SARS-CoV-2 pandemic has resulted in the widespread use of personal protective equipment, particularly face masks. However, the use of commercial disposable face masks puts great pressure on the environment. In this study, nano-copper ions assembled cotton fabric used in face masks to impart antibacterial activity has been discussed. To produce the nanocomposite, the cotton fabric was modified by sodium chloroacetate after its mercerization, and assembled with bactericidal nano-copper ions (about 10.61 mg·g–1) through electrostatic adsorption. It demonstrated excellent antibacterial activity against Staphylococcus aureus and Escherichia coli because the gaps between fibers in the cotton fabric allow the nano-copper ions to be fully released. Moreover, the antibacterial efficiency was maintained even after 50 washing cycles. Furthermore, the face mask constructed with this novel nanocomposite upper layer exhibited a high particle filtration efficiency (96.08% ± 0.91%) without compromising the air permeability (28.9 min·L–1). This green, economical, facile, and scalable process of depositing nano-copper ions onto modified cotton fibric has great potential to reduce disease transmission, resource consumption, and environmental impact of waste, while also expanding the range of protective fabrics.

关键词： cellulose-based     nanocomposite     biodegradable antibacterial fabric     nano-copper ions     face masks    

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Synergistic utilization of coal and other energy – Key to low carbon economy

Weidou NI, Zhen CHEN

《能源前沿（英文）》 2011年 第5卷 第1期   页码 1-19 doi: 10.1007/s11708-010-0136-4

摘要： In China, coal is a dominant component of energy mix, and it is expected to remain as such over the next 30 to 40 years. Coal is expected to be used even more in power generation. The direct combustion of coal already has been causing severe pollution and ecological degradation, and it is quite difficult to address the need to reduce greenhouse gas (GHG) given the direct combustion of coal. Therefore, the polygeneration system based on coal gasification, which is one of the major examples of synergistic utilization of coal, is proposed. It is a comprehensive solution to meet the energy challenges China is facing. Furthermore, the synergy of fossil fuels (especially coal) with renewable energy, the synergy of different kinds of energy for energy storage, the synergy of centralized and distributed supply of different kinds of energy, and the synergy of different kinds of energy in smart energy grid (power, gas, heat, and water) are the keys to making China a low-carbon economy. Carbon dioxide (CO ) mitigation in China should begin from the coal-chemical industry given their accumulated relevant experiences. The mitigation process should gradually be transformed into the “IGCC+ polygeneration+ CCUS”. The objectives of this paper are to describe the synergistic utilization of coal, and to analyze the synergy of coal with other energy resources, and to propose the scientific and technological problems to achieve these synergies.

关键词： synergy     clean and efficient utilization of coal     coal-based polygenration     CO2 mitigation     energy storage    

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hydrogenation of insoluble organic matter of CS/Acetone from coal over mesoporous HZSM-5 supported Ni

《化学科学与工程前沿（英文）》 2022年 第16卷 第10期   页码 1505-1513 doi: 10.1007/s11705-022-2164-0

摘要： Four supported catalysts, nickel and ruthenium on a HZSM-5 support, were prepared by equal volume impregnation and in-situ decomposition of carbonyl nickel. The properties of catalysts were investigated by catalytic hydro-conversion of 2,2′-dinaphthyl ether as the model compound and extraction residue of Naomaohu lignite as the sample under an initial H2 pressure of 5 MPa and temperature at 150 °C. According to the catalytic hydro-conversion results of the model compound, Ni−Ru/HZSM-5 exhibited the best catalytic performance. It not only activated H2 into H···H, but also further heterolytically split H···H into immobile H‒ attached on the acidic centers of Ni−Ru/HZSM-5 and relatively mobile H+. Catalytic hydro-conversion of the extraction residue from Naomaohu lignite was further examined over the optimized catalyst, Ni−Ru/HZSM-5. Detailed molecular compositions of products from the extraction residue with and without hydrogenation were characterized by Fourier transform infrared spectroscopy and gas chromatography/mass spectrometry. The analytical results showed that the oxygen-containing functional groups in products of hydrogenated extraction residue were obviously reduced after the catalytic treatment. The relative content of oxygenates in the product with catalytic treatment was 18.57% lower than that in the product without catalytic treatment.

关键词： HZSM-5     Ni-based catalyst     catalytic hydrogenation     coal     model compound    

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标题 作者 时间 类型 操作

Fabrication and performance of PEN SOFCs with proton-conducting electrolyte

ZHONG Li, LUO Jingli, Karl Chuang

期刊论文

The Immense Impact of Reverse Edges on Large Hierarchical Networks

Haosen Cao,Bin-Bin Hu,Xiaoyu Mo,Duxin Chen,Jianxi Gao,Ye Yuan,Guanrong Chen,Tamás Vicsek,Xiaohong Guan

期刊论文

Ni-Co bimetallic catalyst for CH

Xiaohong LI, Jun AI, Wenying LI, Dongxiong LI

期刊论文

or insufficient: Assessment of the intended nationally determined contributions (INDCs) of the world’s

Ge GAO, Mo CHEN, Jiayu WANG, Kexin YANG, Yujiao XIAN, Xunpeng SHI, Ke WANG

期刊论文

Estimation of relations among hysteretic response measures and design parameters for RC rectangular shear walls

BANAN, Mo. R. BANAN, S. FARHADI

期刊论文

用于复合材料结构生产的编织增强材料树脂灌注工艺模拟

Robert S. Pierce, Brian G. Falzon

期刊论文

Application of consistent geometric decomposition theorem to dynamic finite element of 3D composite beambased on experimental and numerical analyses

Iman FATTAHI, Hamid Reza MIRDAMADI, Hamid ABDOLLAHI

期刊论文

钢箱-混凝土组合梁正截面强度设计理论与试验研究

钟新谷,舒小娟,沈明燕,莫时旭,谢文

期刊论文

Effect of a promoter on the methanation activity of a Mo-based sulfur-resistant catalyst

Can LIN, Haiyang WANG, Zhenhua LI, Baowei WANG, Xinbin MA, Shaodong QIN, Qi SUN

期刊论文

Corrosion behavior of Fe–Cr–Ni based alloys exposed to molten MgCl2–KCl–NaCl salt with over-added

期刊论文

Uncertainty propagation in dynamics of composite plates: A semi-analytical non-sampling-based approach

Mahdi FAKOOR, Hadi PARVIZ

期刊论文

Performance of soft-hard-soft (SHS) cement based composite subjected to blast loading with consideration

Jun WU,Xuemei LIU

期刊论文

Nano-copper ions assembled cellulose-based composite with antibacterial activity for biodegradable personal

期刊论文

Synergistic utilization of coal and other energy – Key to low carbon economy

Weidou NI, Zhen CHEN

期刊论文

hydrogenation of insoluble organic matter of CS/Acetone from coal over mesoporous HZSM-5 supported Ni

期刊论文