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Absorption characteristics of new solvent based on a blend of AMP and 1,8-diamino-p-menthane for CO_2 absorption

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Journal of Environmental Sciences 2012年第5期24卷 897-902页

作者： Sang-Sup Lee Seong-Man Mun Won-Joon Choi Byoung-Moo Min Sang-Won Cho Kwang-Joong Oh department of Environmental Engineering Chungbuk National University department of Environmental Engineering Pusan National University Corporate R&D Institute Fuel Cell System Development Team Doosan Heavy Industries & Construction Greenhouse Gas Research Center Korea Institute of Energy Research department of Energy and Environment Korea Polytechnic VII College

Aqueous 1,8-diamino-p-menthane （KIER-C3） and commercially available amine solutions were tested for CO2 absorption. A 2-amino-2-methyl-1-propanol （AMP） solution with an addition of KIER-C3 showed 9.3% and 31.6% higher absorption rate for CO2 than the AMP solution with an addition of monoethanolamine （MEA） and ammonia （NH3）, respectively. The reaction rate constant for CO2 absorption by the AMP/KIER-C3 solution was determined by the following equation： k2,AMP/C3 = 7.702×106 exp （-2248.03/T）. A CO2 loading ratio of the AMP/KIER-C3 solution was also 2 and 3.4-times higher than that of the AMP/NH3 solution and the AMP/MEA solution, respectively. Based on the experimental results, KIER-C3 may be used as an excellent additive to increase CO2 absorption capability of AMP.

关键词： carbon dioxide absorption rate and capacity 1 8-diamino-p-menthane 2-amino-2-methyl-1-propanol

Insights into the nucleation,grain growth and phase transformation behaviours of sputtered metastableβ-W films

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Journal of Materials Science & Technology 2021年第31期90卷 66-75页

作者： Shuqun Chen Jinshu Wang Ronghai Wu Zheng Wang Yangzhong Li Yiwen Lu Wenyuan Zhou Peng Hua Hongyi Lia Key Laboratory of advanced Functional Materials Education Ministry of ChinaFaculty of Materials and ManufacturingBeijing University of TechnologyBeijing 100124China School of Mechanics Civil Engineering and ArchitectureNorthwestern Polytechnical UniversityXi’an 710129China High Performance Computing department National Supercomputing Center in ShenzhenShenzhen 518055China China Ship development and Design Center Wuhan 430074China

Metastable phase in tungsten film is of great interests in recent years due to its giant spin Hall effects,however,little information has been known on its nucleation,growth and phase *** this paper,a 900 nm-thick tungsten film with double-layer structure(α-W underlayer andβ-W above it)was produced on SiO_(2)/Si substrate by high vacuum magnetron sputtering at room *** structural properties ofβ-W were systemically investigated by X-ray diffraction,transmission electron microscopy,thermodynamic calculation,first-principle and phase-field *** is found that theβ-W nucleation is energetically favoured on the SiO_(2)surface compared to theα-W *** the film thickening proceeds,β-W[211]turns to be preferred direction of growth owing to the elastic strain energy minimization,which is verified by phase-field ***,theβ→αphase transformation takes place near the film-substrate interface while the rest of the film keeps theβ-W phase,leading to a doublelayer *** localized phase transition is induced by lower Gibbs free energy ofα-W phase at larger grain sizes,which can be confirmed by thermodynamic *** in-situ heating TEM analysis of the as-deposited film reveals that theβ→αphase transformation is fulfilled byα/βinterface propagation rather than local atomic *** findings offer valuable insights into the intrinsic properties of metastable phase in tungsten.

关键词： Metastable phases Tungsten Nucleation and growth Phase field modelling Phase transformation

Electrode Wear Prediction in Milling Electrical Discharge Machining Based on Radial Basis Function Neural Network

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Journal of Shanghai Jiaotong university(Science) 2009年第6期14卷 736-741页

作者：黄河白基成卢泽生郭永丰 department of manufacturing and Automation Engineering Harbin Institute of Technology

Milling electrical discharge machining(EDM) enables the machining of complex cavities using cylindrical or tubular *** ensure acceptable machining accuracy the process requires some methods of compensating for electrode *** to the complexity and random nature of the process,existing methods of compensating for such wear usually involve off-line *** paper discusses an innovative model of electrode wear prediction for milling EDM based upon a radial basis function(RBF) *** gained from an orthogonal experiment were used to provide training samples for the RBF *** model established was used to forecast the electrode wear,making it possible to calculate the real-time tool wear in the milling EDM process and,to lay the foundations for dynamic compensation of the electrode wear *** paper demonstrates that by using this model prediction errors can be controlled within 8%.

关键词： milling electrical discharge machining (EDM) electrode wear prediction radial basis function (RBF) neural network

In situ formed ultrafine metallic Ni from nickel(Ⅱ) acetylacetonate precursor to realize an exceptional hydrogen storage performance of MgH_(2)-Ni-EG nanocomposite

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Journal of Magnesium and Alloys 2023年第9期11卷 3174-3185页

作者： Shaoyang Shen Liuzhang Ouyang Jiangwen Liu Hui Wang Xu-Sheng Yang Min Zhu School of Materials Science and Engineering and Key Laboratory of advanced Energy Storage Materials of Guangdong Province South China University of TechnologyGuangzhou510641China China-Australia Joint Laboratory for Energy&Environmental Materials Key Laboratory of Fuel Cell Technology of Guangdong ProvinceGuangzhouGuangzhou510641China advanced manufacturing Technology Research Centre Department of Industrial and Systems EngineeringThe Hong Kong Polytechnic UniversityHung HomKowloonHong KongChina Research Institute for Smart Energy The Hong Kong Polytechnic UniversityHung HomKowloonHong KongChina

It has been well known that doping nano-scale catalysts can significantly improve both the kinetics and reversible hydrogen storage capacity of MgH_(2) . However, so far it is still a challenge to directly synthesize ultrafine catalysts(e.g., < 5 nm), mainly because of the complicated chemical reaction processes. Here, a facile one-step high-energy ball milling process is developed to in situ form ultrafine Ni nanoparticles from the nickel acetylacetonate precursor in the MgH_(2) matrix. With the combined action of ultrafine metallic Ni and expanded graphite(EG), the formed MgH_(2)-Ni-EG nanocomposite with the optimized doping amounts of Ni and EG can still release 7.03 wt.% H_(2) within 8.5 min at 300 ℃ after 10 cycles. At a temperature close to room temperature(50 ℃), it can also absorb 2.42 wt.% H_(2) within 1 h. It can be confirmed from the microstructural characterization analysis that the in situ formed ultrafine metallic Ni is transformed into Mg_(2)Ni/Mg_(2)NiH_4 in the subsequent hydrogen absorption and desorption cycles. It is calculated that the dehydrogenation activation energy of the MgH_(2)-Ni-EG nanocomposite is also reduced obviously in comparison with the pure MgH_(2) . Our work provides a methodology to significantly improve the hydrogen storage performance of MgH_(2) by combining the in situ formed and uniformly dispersed ultrafine metallic catalyst from the precursor and EG.

关键词： Hydrogen storage Magnesium hydride Nickel precursor Size effect Expanded graphite

Microscopic strengthening and failure mechanisms of graphene/Al composite: A molecular dynamics study

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Progress in Natural Science:Materials International 2024年第4期34卷 720-730页

作者： Huijuan Guo Xiaoyan Sun Liang Chen Yuhui Zhao Kaiqiang Shen Xiangshan Kong State Key Laboratory of advanced Equipment and Technology for Metal Forming Shandong University Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials (Ministry of Education) Shandong University Intelligent manufacturing department Yantai Engineering and Technology College

This study focused on the microscopic strengthening and failure mechanisms of the Al matrix reinforced by graphene(Gr), and the effects of number of layers, chirality, and arrangement of Gr were calculated based on the molecular dynamics simulation. The results revealed that the Young's modulus and yield strength were significantly enhanced by the addition of Gr. In Gr/Al composites with monolayer Gr, the zigzag Gr exhibited a better ultimate strain than the armchair Gr, indicating that the plastic deformation was affected by the chirality, and the dislocation hindrance and load transfer were the dominated strengthening mechanisms. The crack in the armchair Gr was limited to follow straight paths, while that in zigzag Gr extended in a petal-like manner across multiple directions. In Gr/Al composite with multilayer Gr, the dispersing Gr showed a stronger strengthening effect than the stacking Gr, and the strengthening effect increased with increasing the volume fraction of Gr. The dispersing Gr strongly hindered the movement of dislocations, while the Al matrix in the composite with stacking Gr could retard the folding of Gr. Moreover, Gr nanosheets fractured layer by layer rather than simultaneously fractured in the Gr/Al composites with multilayer Gr.

关键词： Molecular dynamics Gr/Al composites Strengthening Failure

Particle Swarm Optimization based predictive control of Proton Exchange Membrane fuel Cell (PEMFC)

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第3期7卷 458-462页

作者：任远曹广益朱新坚 Institute of fuel Cell Department of Automation Shanghai Jiao Tong University Shanghai 20030 China

Proton Exchange Membrane fuel Cells (PEMFCs) are the main focus of their current development as power sources because they are capable of higher power density and faster start-up than other fuel cells. The humidification system and output performance of PEMFC stack are briefly analyzed. Predictive control of PEMFC based on Support Vector Regression Machine (SVRM) is presented and the SVRM is constructed. The processing plant is modelled on SVRM and the predictive control law is obtained by using Particle Swarm Optimization (PSO). The simulation and the results showed that the SVRM and the PSO re-ceding optimization applied to the PEMFC predictive control yielded good performance.

关键词： Support Vector Regression Machine (SVRM) Proton Exchange Membrane fuel Cell (PEMFC) Particle Swarm Optimization (PSO) Predictive control

Singular and Regular Implementations of the Hybrid Boundary Node Method

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Tsinghua Science and Technology 2007年第5期12卷 509-519页

作者：张见明 Masa Tanaka 姚振汉 State Key Laboratory of advanced Design and manufacturing for Vehicle Body College of Mechanical and Automotive EngineeringHunan University Faculty of Engineering Shinshu University department of Engineering Mechanics Tsinghua University

The hybrid boundary node method （HdBNM） combines a modified function with the moving least squares approximation to form a boundary-only truly meshless method. This paper describes two implementations of the HdBNM, the singular hybrid boundary node method （ShBNM） and the regular hybrid boundary node method （RhBNM）. The ShBNM and RhBNM were compared with each other, and the parameters that influence their performance were studied in detail. The convergence rates and their applicability to thin structures were also investigated. The ShBNM and RhBNM are found to be very easy to implement and to efficiently obtain numerical solutions to computational mechanics problems.

关键词： meshless methods hybrid boundary node method moving least squares approximation

Estimation of equivalent internal-resistance of PEM fuel cell using artificial neural networks

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Journal of Central South University of Technology 2007年第5期14卷 690-695页

作者：李炜朱新坚莫志军 department of Automation Fuel Cell Research Institute Shanghai Jiaotong University

A practical method of estimation for the internal-resistance of polymer electrolyte membrane fuel cell (PEMFC) stack was adopted based on radial basis function (RBF) neural networks. In the training process, k-means clustering algorithm was applied to select the network centers of the input training data. Furthermore, an equivalent electrical-circuit model with this internal-resistance was developed for investigation on the stack. Finally using the neural networks model of the equivalent resistance in the PEMFC stack, the simulation results of the estimation of equivalent internal-resistance of PEMFC were presented. The results show that this electrical PEMFC model is effective and is suitable for the study of control scheme, fault detection and the engineering analysis of electrical circuits.

关键词： polymer electrolyte membrane fuel cell(PEMFC) equivalent internal-resistance radial basis function neural networks

Detection of free surface composition and molecular-level structural development of styrene(S)/butadiene(B) block copolymer films during a solution-to-film process

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Science China Chemistry 2012年第7期55卷 1263-1273页

作者： YAN ZhuoHua ZHANG RongPing ZHAO YuRong ZUO Biao ZHENG FanFan CHEN TianYu WANG XinPing SHEN ZhiQuan Key Laboratory of advanced Textile Materials and manufacturing Technology of Ministry of Education Department of Chemistry Zhejiang Sci-Tech UniversityHangzhou 310018China Institute of Polymer Science Zhejiang UniversityHangzhou 310027China

The surface chemical structure development in solution-cast styrene(S)/butadiene(B) block copolymer films as a function of solvent evaporation time was investigated using sum frequency generation vibrational spectroscopy(SFG).The surface structure formation of the styrene(S)/butadien(B) block copolymer(30 wt% PS) films during the solution-to-film process was found to be controlled mainly by dynamic factors,such as the mobility of the PB block in *** SB diblock copolymers,a pure PB surface layer was formed only when the film was cast by dilute toluene *** increasing concentration of casting solution,PB and PS components were found to coexist on the film surface,and the morphology of the PB component on the film surface changed from cylindrical rods to *** SBS triblock copolymers,a small amount of PS component existed on the surface even if the film was cast by 1.0 wt% toluene *** addition,PS components at the outermost layer of the film increased and the length of PB cylindrical rods on the surface decreased with increasing concentration of casting solution.

关键词： styrene/butadiene block copolymer chain architecture casting solution concentration surface structure sum frequen-cy generation vibrational spectroscopy