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NUMERICAL SIMULATION OF A HORIZONTAL MOMENTUM JET IN CROSS-FLOW

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Journal of Hydrodynamics 2006年第1期18卷 118-125页

作者： XIAO yang TANG hong-wu College of Water Conservancy and Hydropower Engineering Hohai University Nanjing 210098 China

The mixing characteristics of a Horizontal Momentum Jet in Cross flow （HMJC） were investigated using the CFD code Fluent. The realizable k-ε model was employed for turbulent closure of the Reynolds-averaged Navier-Stokes equations. The computed results, including concentration field and velocity field, agree well with the relations of dimen sional analysis, as well as the experimental results by Sherif and Pletcher, Ali and Yu et al.

关键词： horizontal momentum jet cross-flow realizable k-ε model LIF PIV

Mixed B-site ruddlesden-popper phase Sr_(2)(Ru_(x)Ir_(1-x))O_(4) enables enhanced activity for oxygen evolution reaction

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Journal of Energy Chemistry 2022年第7期31卷 623-629,I0015页

作者： Fangfang Wang Cheng Zhang hong yang Department of Chemical and Biomolecular Engineering University of Illinois at Urbana-ChampaignUrbanaIL 61801USA School of Mechanical and Power Engineering Zhengzhou UniversityZhengzhou 450001HenanChina

Development of high performance electrocatalysts for oxygen evolution reaction (OER) in acidic media remains a challenge for direct water splitting using an ***,Ruddlesden-Popper phase Sr_(2)IrO_(4)was discovered to be an efficient OER catalyst because of its unique structure,which consists of layers of both rock salt and perovskite phases *** this study,we prepared a series of B-site mixed,Ruddlesden-Popper phase of Sr_(2)(Ru_(x)Ir_(1-x))O_(4) and examined their electrocatalytic properties for OER in acidic *** partial substitution of Ru in the B-site of Ruddlesden-Popper phase materials,we achieved much enhanced OER performance for this series of Sr_(2)(Ru_(x)Ir_(1-x))O_(4)electrocatalysts,among which Sr_(2)(Ru_(0.5)Ir_(0.5))O_(4)exhibited the best catalytic activity with a current density of 8.06 m A/cm^(2) at 1.55 V and a Tafel slope of 47 m V/*** current density is three times higher than that of Sr_(2)Ir O_(4).The B-site mixed Sr_(2)(Ru_(0.5)Ir_(0.5))O_(4)retained good stability in acidic conditions for>24 h at 10 m A/cm^(2).A range of techniques were used to characterize the crystal and electronic structures of the Sr_(2)(Ru_(x)Ir_(1-x))O_(4)*** data indicate that the improved OER performance can be correlated to the formation of high level of hydroxyl groups and the enhanced overlap between Ir/Ru 4d and O_(2)p orbitals,revealing a new way for the design of efficient OER electrocatalysts by regulating their composition and electronic structures.

关键词： Water splitting OER Electrocatalyst Ruddlesden-Popper Strontium ruthenium iridium oxide

PtAu Bimetallic Heteronanostructures Made by Post-Synthesis Modification of Pt-on-Au Nanoparticles

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Nano Research 2009年第5期2卷 406-415页

作者： Zhenmeng Peng hong yang Department of Chemical Engineering University of RochesterGavett Hall 206RochesterNY 14627USA

Bimetallic PtAu heteronanostructures have been synthesized from Pt-on-Au nanoparticles,which were made from platinum acetylacetonate and gold *** the Pt-on-Au nanoparticles as precursors,Pt-surface rich PtAu bimetallic heteronanostructures can be produced through controlled thermal treatments,as confirmed by field emission high-resolution transmission electron microscopy(HR-TEM)and elemental mapping using a high-angle annular dark-field scanning transmission electron microscope(HAADF-STEM).Oxidation of formic acid was used as a model reaction to demonstrate the effects of varying composition and surface structure on the catalytic performance of PtAu bimetallic *** voltammetry(CV)showed that these carbon-supported PtAu heteronanostructures were much more active than platinum in catalyzing the oxidation of formic acid,judging by the mass current *** results showed that post-synthesis modification can be a very useful approach to the control of composition distributions in alloy nanostructures.

关键词： Nanostructure alloy platinum gold formic acid oxidation electrocatalyst polymer electrolyte membrane fuel cell(PEMFC)

Synthesis and Electrocatalytic Oxygen Reduction Properties of Truncated Octahedral Pt3Ni Nanoparticles

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Nano Research 2011年第1期4卷 72-82页

作者： Jianbo Wu hong yang Department of Chemical Engineering University of Rochester Gavett Hall 206 Rochester New York 14627 USA

Pt3Ni nanoparticles have been obtained by shape-controlled synthesis and employed as oxygen reduction electrocatalysts for proton exchange membrane fuel cells （PEMFC）. The effects of varying the synthesis parameters such as the types of the capping agent and the reducing agent, and the reaction time have been systematically studied. The as-prepared PtBNi nanoparticles were subjected to a butylamine-based surface treatment in order to prepare carbon-supported electrocatalysts. The Pt3Ni electrocatalysts show an area- specific activity of 0.76 mA/cm2（pt） at 0.9 V in an alkaline electrolyte, which is 4.5 times that of a commercial Pt/C catalyst （0.17 mA/cm2 （Pt））. The mass activity reached 0.30 A/mg（Pt） at 0.9 V, which is about twice that of the commercial Pt/C catalyst. Our results also show that the area-specific activities of these carbon-supported Pt3Ni electrocatalysts depend strongly on the （111） surface fraction, which is consistent with the results of a study based on Pt3Ni extended single-crystal surfaces.

关键词： Pt-based alloy oxygen reduction reaction shape control alkaline solution truncated octahedron

A New Approach to Inducing Silicon Tethered Ring-closing Metathesis Reactions

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Chemical Research in Chinese Universities 2002年第4期18卷 414-418页

作者： yang hong-li VAULTIER Miche Synthèse et Electrosynthèse Organiques UMR CNRS 6510Universitéde Rennes 1Campus de BeaulieuAvenue du Général Leclerc35042 RENNES CEDEXFrance

Ring-closing metathesis reactions involving diallyldiphenylsilane and diallyloxydiphenylsilane were successfully performed by using only 0 01 mol or even less of Grubbs' catalyst 1. The effects of reaction parameters... 详细信息

关键词： Ring-closing metathesis reaction Grubbs' catalyst Diallyldiphenylsilane Diallyloxydiphenyl-silane

Extraction study of rare earth elements with N,N'-dibutyl–N,N'-di(1-methylheptyl)-diglycolamide from hydrochloric acid

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Nuclear Science and Techniques 2016年第3期27卷 186-193页

作者： Guo-Jing Sun Jin-hong yang hong-Xiao yang Guo-Xin Sun Yu Cui School of Chemistry and Chemical Engineering University of Jinan

A novel,unsymmetrical diglycolamide,N,N'-dibutyl-N,N'-di(1-methylheptyl)-diglycolamide(DBD1MHDGA),was *** extraction of rare earth elements(REEs) from a hydrochloric acid medium with DBD1 MHDGA was *** results of the extraction experiments indicated that the distribution ratios of RE(Ⅲ) ions increase with an increase in HC1 concentration,atomic number,and extractant *** calculated thermodynamic data show that the extraction process is an exothermic *** organic phase loaded rare earth ions were characterized by infrared *** composition of the extracted complex was determined.

关键词：稀土元素盐酸介质萃取剂庚基红外光谱表征盐酸浓度稀土离子分配比例

A kind of biomimetic control method to anthropomorphize a redundant manipulator for complex tasks

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Science China(Technological Sciences) 2020年第1期63卷 14-24页

作者： MO yang JIANG Zhihong LI Hui yang hong HUANG Qiang School of Mechatronic Engineering Beijing Institute of TechnologyBeijing 100081China Beijing Advanced Innovation Center for Intelligent Robots and Systems Beijing 100081China Key Laboratory of Biomimetic Robots and Systems Ministry of EducationBeijing 100081China Institute of Manned Spacecraft System Engineering China Academy of Space TechnologyBeijing 100080China

It is an urgent problem for robots to operate complex tasks with some unknown motion mechanisms caused by the strong coupling of force and motion. However, humans can perform complex tasks well due to their natural evolution and postnatal training. A novel biomimetic control method based on a human motion mechanism with high movement adaptability is proposed in this paper. The core is to present a novel variable-parameter compliance controller based on human operation mechanisms with an action-planning method derived from optimization by human motion, and the main contribution is to change the parameters of compliance controller according to human operating intention synchronized with humanoid motion;this change could establish a humanoid map between the force and motion for a seven degree-of-freedom redundant manipulator to deal with the unknown motion mechanism in complex tasks, so the redundant manipulator can operate complex tasks with high performance. Sufficient experiments were performed, and the results validated the effectiveness of the proposed algorithm.

关键词： redundant manipulator biomimetic control humanoid mapping complex task

Attack detectability and stealthiness in distributed optimal coordination of cyber-physical systems

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Science China(Information Sciences) 2023年第9期66卷 301-302页

作者： Liwei AN Guang-hong yang College of Information Science and Engineering Northeastern University State Key Laboratory of Synthetical Automation for Process Industries(Northeastern University)

With potential applications of distributed optimization(DO) in large-scale cyber-physical systems(CPSs), many important results on distributed optimal coordination(DOC) algorithms have been reported for multi-agent systems with various physical dynamics, which have wide applications such as the cooperative search of radio sources, the motion coordination, and the distributed optimal power flow(see [1] and references therein).

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Effect of Magnetic-Impurity Scattering in Disordered Two-Dimensional Square Lattices Around Half Filling

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Communications in Theoretical Physics 2005年第5X期44卷 929-935页

作者： QIAN Feng yang Yong-hong Department of Physics Southeast University Nanjing 210096 China National Laboratory of Solid State Microstructures Nanjing University Nanjing 210008 China

Abstract Weak-localization effect in the presence of magnetic impurities is studied in disordered two-dimensional tight-binding square lattices around half filling. Both the magnetic and nonmagnetic impurities are assumed to be randomly distributed on small fractions of the sites, while the nonmagnetic impurities have a strong potential yielding a unitary-limit scattering. We derive in details the expressions of diffusive π modes in the retarded-retarded （or advanced- advanced） channel, which result from the existence of particle-hole symmetry. The quantum interference correction to the density of states is calculated. While the magnetic-impurity scattering suppresses the quantum correction from π-mode cooperon, it does not affect the contribution of π-mode diffuson.

关键词： weak localization magnetic impurity density of states two-dimensional lattice