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Rare Metals 2019年第2期38卷 107-114页

作者： Kai Shen Jia-Pan Lin Qian Xia lu dai Guo-Jun Zhou Yang-Long Guo Guan-Zhong lu Wang-Cheng Zhan Technology Center China Tobacco Zhejiang Industrial Co.Ltd. Key Laboratory for Advanced Materials and Research Institute of Industrial Catalysis East China University of Science and Technology

A series of 0.2 wt% Pd/Sn_(0.9)Ce_(0.1)O_2 catalysts were prepared by impregnation method based on the presynthesis of Sn_(0.9)Ce_(0.1)O_2 support prepared by co-precipitation method, and then characterized by Brunauer–Emmett–Teller(BET), X-ray diffraction(XRD), X-ray photoelectron spectroscopy(XPS), Raman, CO chemical adsorption and hydrogen temperature-programmed reduction(H_2-TPR) techniques. The effect of calcination temperature of the composite oxide support on the catalytic performances of the Pd/Sn_(0.9)Ce_(0.1)O_2 catalyst for the CH_4 total oxidation was studied. It is found that the catalytic activity of the Pd/Sn_(0.9)Ce_(0.1)O_2 catalyst increases with the increase in calcination temperature of the Pd/Sn_(0.9)Ce_(0.1)O_2 support. The 0.2 wt% Pd/Sn_(0.9)Ce_(0.1)O_2/1100 catalyst(the Pd/Sn_(0.9)Ce_(0.1)O_2 support was calcined at 1100 ℃) exhibits the best reactive activity(T_(10)= 255 ℃). The excellent activity of the 0.2 wt% Pd/Sn_(0.9)Ce_(0.1)O_2/1100 catalyst should be attributed to the high reducibility of PdO, the excellent oxygen mobility of the support and the high content of active Pd^(2+) species on the Pd/Sn_(0.9)Ce_(0.1)O_2 catalyst.

关键词： Catalytic combustion Methane PdO SnxCe1-xO2 Calcination temperature

Electrochemical Activation-Induced Structural Transformation in Ni(OH)_(2)/Ti_(3)C_(2)T_(x)/NF Systems with Enhanced Electrochemical Performance for Hybrid Supercapacitors

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Energy & Environmental Materials 2024年第4期7卷 277-284页

作者： Chuming Xu lu dai Yiming Zhao Shuang Li Yapan Wu Xueqian Wu Gaixia Zhang Shuhui Sun Dongsheng Li College of Materials and Chemical Engineering Key Laboratory of Inorganic Nonmetallic Crystalline and Energy Conversion MaterialsChina Three Gorges UniversityYichang 443002China Hubei Three Gorges Laboratory Yichang 443007China Department of Electrical Engineering École de Technologie Supérieure(ÉTS)MontréalQuébec H3C 1K3Canada Institut National de la Recherche Scientifique(INRS) CentreÉnergie Matériaux TélécommunicationsVarennesQuébec J3X 1P7Canada

Exploring a novel strategy for large-scale production of battery-type Ni(OH)_(2)-based composites,with excellent capacitive performance,is still greatly ***,we developed a facile and cost-effective strategy to in situ grow a layer of Ni(OH)_(2)/Ti_(3)C_(2)T_(x)composite on the nickel foam(NF)collector,where Ti_(3)C_(2)T_(x)is not only a conductive component,but also a catalyst that accelerates the oxidation of NF to Ni(OH)_(2).Detailed analysis reveals that the crystallinity,morphology,and electronic structure of the integrated electrode can be tuned via the electrochemical activation,which is beneficial for improving electrical conductivity and redox *** expected,the integrated electrode shows a specific capacity of 1.09 C cm^(-2)at 1 mA cm^(-2)after three custom activation cycles and maintains 92.4%of the initial capacity after 1500 ***,a hybrid supercapacitor composed of Ni(OH)_(2)/Ti_(3)C_(2)T_(x)/NF cathode and activated carbon anode provides an energy density of 0.1 mWh cm^(-2)at a power density of 0.97 mW cm^(-2),and excellent cycling stability with about 110%capacity retention rate after 5000 *** work would afford an economical and convenient method to steer commercial Ni foam into advanced Ni(OH)_(2)-based composite materials as binder-free electrodes for hybrid supercapacitors.

关键词： electrochemical activation hybrid supercapacitors Ni(OH)_(2) Ti_(3)C_(2)T_(x)

Design and analysis of bidirectional deployable parabolic cylindrical antenna

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2014年第2期15卷 83-96页

作者： Tian YU Fu-ling GUAN lu dai College of Civil Engineering and Architecture Zhejiang University Hangzhou 310058 China

A bidirectional deployable parabolic cylindrical reflector for an L-band synthetic aperture radar is presented in this study, in which a self-deployed antenna with low weight was designed. The antenna consists of four curved surfaces formed from thin sheets of composite materials connected by hinges along the edges, and the reflective surface is provided by the front surface. The edge profiles of connecting lines were obtained through geometric analysis. A scaled model, including design and manufac- ture, was demonstrated to validate the process from the folded state to the fully deployed state. The non-contact synchronous vision measuring method was used to test the basic frequency of the scaled model, and the test results gave the verification of the analyses. Compared with the existing unidirectional deployable antenna, this new type of bidirectional deployable antenna can be applied to larger-size antennas and has better performance because the glass-woven tape connections were substituted with more reliable hinges. Static, modal, harmonic response, and transient response analyses of the full-sized reflector structure were mod- eled with the commercial finite element （FE） package ABAQUS. The modeling techniques were developed to predict the struc- tural dynamic behavior of the reflector and the results showed that the first natural frequency was 0.865 Hz, and the reflector structure had good stiffness in three directions. This proposed structure has very high stiffness-to-mass ratio because of its hollow solid construction. A preliminary simulation of radiation properties of the parabolic cylindrical antenna, fed by an off-set linear feed horn array, was conducted to obtain the radiation pattern of the feed and the reflector.

关键词： Parabolic cylindrical antenna Geometric analysis Deploying and folding process Frequency test Structuralanalysis Radiation property

LABORATORY STUDIES ON WAVE FORCE OF COASTAL STRUCTURES MADE OF FLAT GEOTUBES

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Journal of Hydrodynamics 2011年第6期23卷 820-825页

作者： LIN Gang SHU Yi-ming lu Xin dai Lin-jun YU Xin-zhou ZHANG Xian-lei YI Jing-rong College of Water Conservancy and Hydropower Engineering Hohai University Nanjing 210098 China

Flat geotubes are widely used for coastal structures such as seawalls, breakwaters and sightseeing groins, etc.. However, the understanding of the stable mechanism involved in the wave-structure interactions should be deepened, and one of the important work is to clarify the stress state of the structure under the wave action. In this article, wave force acting on coastal structures made of flat geotube is experimentally investigated. The required drag, inertia and lift coefficients are especially analyzed from the results of hydraulic model experiments specially designed for geotube structure. Several types of structures made of flat geotubes under wave action have been tested in order to understand the stress state of the geotube fixed to force transducer within different structures. Experimental results show that the wave-induced forces on the instrumented geotube are markedly influenced by wave elements. Meanwhile, the magnitude of horizontal force of adjoining geotube is different at the same time.

关键词： flat geotube wave force coefficients inertial force drag lift coastal structure hydraulic model experiment

3-D velocity structure in the central-eastern part of Qilianshan

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Acta Seismologica Sinica(English Edition) 2004年第3期17卷 272-281页

作者： ZHANG Yuan-sheng(张元生) ZHOU Min-du(周民都) RONG dai-lu(荣代潞) ZHANG Li-guang(张立光) XU Zhong-qiu(许中秋) Lanzhou Institute of Seismology China Earthquake Administration Lanzhou 730000 China Lanzhou Institute of Seismology China Earthquake Administration Lanzhou 730000 China Lanzhou Institute of Seismology China Earthquake Administration Lanzhou 730000 China Lanzhou Institute of Seismology China Earthquake Administration Lanzhou 730000 China Earthquake Administration of Lanzhou City Lanzhou 730000 China

The 3-D velocity tomography image of the central-eastern part of Qilianshan is obtained by the joint inversion of 3-D velocity structure and focal parameters based on the S-P data of micro-earthquakes recorded by the digital seismic network set up for a Sino-French cooperation program since 1996. The inversed velocity structure does primarily reflect some important features of the deep structure in the region and provide the scientific background for the further study of active tectonic structure and the calculation of earthquake parameters.

关键词： central-eastern Qilianshan micro-earthquake observation 3-D velocity structure focal pa-rameters joint inversion

Solvent effects on oxygen atom transfer reaction between manganese(V)-oxo corrole and alkene

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Chinese Chemical Letters 2013年第6期24卷 447-449页

作者： Lan Yu Qi Wang lu dai Wei-Ying Li Rong Chen Mian HR Mahmood Hai-Yang Liu Chi-Kwong Chang Department of Chemistry South China University of Technology Department of Chemistry Michigan State University

Pseudo-first order reaction rate constants of 5,10,15-tris（pentafluorophenyl）corrole Mn（V）-oxo （F_（15）CMn（V）-oxo）,5,15-bis（pentafluorophenyl）-10-（phenyl）corrole Mn（V）-oxo（F_（10）CMn（V）-oxo）,5,15- bis（phenyl）-10-（pentafluorophenyl）corrole Mn（V）-oxo（F_5CMn（V）-oxo） and 5,10,15-tris（phenyl）corrole Mn（V）-oxo（F_0CMn（V）-oxo） with a series of alkene substrates in different solvents were determined by UV-vis *** results indicated that the oxygen atom transfer pathway between Mn（V）-oxo corrole and alkene is solvent-dependent.

关键词： Corrole Mn(V)-oxo corrole Oxygen atom transfer reaction Solvent effect

Modeling the rate-dependent ductile-brittle transition in amorphous polymers

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Acta Mechanica Sinica 2022年第7期38卷 45-52,I0001页

作者： Ji Lin lu dai Jin Qian Rui Xiao State Key Laboratory of Fluid Power&Mechatronic System Key Laboratory of Soft Machines and Smart Devices of Zhejiang ProvinceDepartment of Engineering MechanicsZhejiang UniversityHangzhou310027China School of Civil Engineering and Architecture Zhejiang Sci-Tech UniversityHangzhou310018China

The stress response of amorphous polymers in the glass transition region shows apparent temperature and rate *** increasing loading rate,amorphous polymers also exhibit a clear ductile-brittle transition of tensile *** rate-dependent behaviors originate from intrinsic relaxations,ranging from perturbation of molecular bonds between polymer segments to reptation of polymer *** this work,we develop a constitutive model that incorporates segmental and chain dynamics into the deformation of bond and polymer networks,*** dynamic scission of polymer chains is also incorporated into the theoretical framework to describe the damage evolution and ultimate failure of polymers.A comparison between theoretical predictions and experiments shows that the present model is able to simultaneously capture the observed rate-dependent features,including the transition from glassy state to rubbery state,strain hardening,and failure threshold.

关键词： Amorphous polymer Ductile-brittle transition Glass transition Constitutive model

Tuning interaction strength between CeO_(2) and iridium to promote CO oxidation over Ir/TiO_(2)

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Journal of Rare Earths 2024年第4期42卷 651-659页

作者： lu dai Binghua Li Yuhan Peng Xianwei Hao Runquan Xuan Hua Huang Yiming Bi Liping Xu Yanhui Zhang Yun Guo Fangqi Du Li Wang Hui Wang Technology Center China Tobacco Zhejiang Industrial Co.Ltd.Hangzhou310024China Research Institute of Industrial Catalysis East China University of Science and TechnologyShanghai200237China

The interaction between support and noble metal plays a crucial role in heterogeneous catalysis ***,how to tune metal support interactions to optimize the activity still needs further ***_(2) was introduced to promote CO oxidation ove r Ir/TiO_(2) by adjusting the interaction strength between iridium(Ir)and CeO_(2).The strong interaction between Ir and CeO_(2) blocks CO adsorption and causes low CO oxidation ***,introducing CeO_(2) on Ir/TiO_(2) produces localized interaction between Ir and CeO_(2),which can tune the surface electronic state of Ir,so a"volcano curve"relationship between CO oxidation activity and electronic state is *** amount of CeO_(2) on Ir/TiO_(2)(Ir/Ce_(0.2)Ti)leads to CO complete oxidization at 22℃,and a new pathway for CO oxidation was *** study demonstrates that the utilization of tuning interaction strength between active metal and support is a potential method to increase the catalytic activity.

关键词： CO oxidation CeO_(2) Localized interaction Interaction strength Supported Ir catalysts Rareearths

Vision-Based Fixed-Time Platoon Formation Control of Multi-Agent Systems

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Vision-Based Fixed-Time Platoon Formation Control of Multi-A...

第三十九届中国控制会议

作者： Ke lu Min Wang Shi-lu dai School of Automation Science and Engineering South China University of Technology

This paper presents an adaptive fixed-time formation control of nonholonomic mobile robots subject to limited sensing capability. A fixed-time cooperative control method is considered since it can provide the stability of the closed-loop system and guarantee convergence time of system trajectories independently on initial conditions. In addition, performance constraints are introduced in control strategy, imposed on formation tracking errors to guarantee the transient and stead-state ***, connectivity maintenance and collision avoidance are fully taken into account to prevent multi-agent systems deterioration. Consequently, the barrier Lyapunov function is incorporated into formation controller design such that under the proposed control method, the formation tracking errors can converge into a small neighbourhood of zero in fixed settling time even though the feedback signals are only the relative distance and bearing angle. Simulation results demonstrate the effectiveness of the proposed formation controller.

关键词： Vision-based formation control fixed-time tracking vehicle platoon barrier Lyapunov function

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“黑碧”OH振动光谱产生分裂原因探究

光谱学与光谱分析 2021年第12期41卷 3864-3868页

作者：代路路杨明星中国地质大学(武汉)珠宝学院湖北武汉430074 中国地质大学(武汉)珠宝检测中心湖北武汉430074

“黑碧”指颜色为黑色,主要成分为阳起石的碧玉。电子探针、激光剥蚀电感耦合等离子体质谱仪分析显示“黑碧”为阳起石碧玉。拉曼光谱和红外光谱的OH振动处产生3个主峰,归属于MgMgMg-OH,MgMgFe^(2+)-OH(Fe^(2+)_(M1 )Mg_( M1 )Mg M3-OH,... 详细信息

“黑碧”指颜色为黑色,主要成分为阳起石的碧玉。电子探针、激光剥蚀电感耦合等离子体质谱仪分析显示“黑碧”为阳起石碧玉。拉曼光谱和红外光谱的OH振动处产生3个主峰,归属于MgMgMg-OH,MgMgFe^(2+)-OH(Fe^(2+)_(M1 )Mg_( M1 )Mg M3-OH,Mg _(M1) Mg _(M1) Fe^(2+)M3-OH),MgFe^(2+)Fe^(2+)-OH(Mg_( M1) Fe^(2+)_(M1) Fe^(2+)_(M3)-OH,Fe^(2+)_(M1) Fe^(2+)_(M1) Mg_(M3)-OH),但与常见和田玉不同,“黑碧”的三个主峰在拉曼光谱OH的振动区(3600~3700 cm^(-1))和红外光谱OH的倍频振动区(7200~7100 cm^(-1))产生分裂现象。将“黑碧”分为5个区域:HB-1,HB-2,HB-3,HB-4和HB-5,进行原位的电子探针和拉曼光谱分析,拉曼光谱在3600~3700 cm^(-1)出现3个主峰(A,B,C),将主峰进行分峰拟合处理,显示分裂成6个次级峰(A′和A″,B′和B″,C′和C″),次级峰之间的平均波数差为5 cm^(-1)。前人对角闪石在OH振动处主峰分裂现象的观点各不相同。结合“黑碧”的原位电子探针数据和相关研究文献,认为角闪石中B(M4)位置上的阳离子分布是分裂谱产生的主要原因。角闪石中的B(M4)位置虽然没有直接与W位置的OH相连接,但B(M4)位置上的阳离子通过影响TO 4上的桥氧,间接影响W位置上的OH,从而引起OH振动光谱产生一定变化。对比存在类似分裂谱的角闪石样品和“黑碧”的晶体化学式,发现所有的样品在B(M4)位置上均存在Ca^(2+)和Mn^(2+)分布,而其他位置的阳离子占位情况都不相同,表明“黑碧”OH振动光谱产生分裂与B(M4)位置上的Ca 2+和Mn^(2+)分布有关。故认为“黑碧”中OH振动光谱产生分裂原因为Ca 2+和Mn^(2+)在B(M4)位置上的占位,且高波数峰位归属于Ca^(2+),低波数峰位归属于Mn^(2+),即A′,B′,C′归属于Ca 2+,A″,B″,C″归属于Mn^(2+)。

关键词： “黑碧” 角闪石 OH振动光谱分裂