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Nano Research 2017年第9期10卷 3178-3188页

作者： Jung Hyun Kim Yun chan Kang Department of Materials Science and Engineering Korea University Anam-Dong Seongbuk-Gu Seou1136-713 Republic of Korea

Multicomponent metal sulfide materials with a yolk–shell structure and a single phase were studied for the first time as anode materials for sodium-ion batteries. Yolk–shell-structured Fe–Ni–O powders with a molar ratio of iron and nickel components of 1/1 were prepared via one-pot spray pyrolysis. The prepared Fe–Ni–O powders were transformed into yolk–shell-structured (Fe0.5Ni0.5)9S8 solid-solution powders via a sulfidation process. The initial discharge and charge capacities of the (Fe0.5Ni0.5)9S8 powders at a current density of 1 A·g−1 were 601 and 504 mA·h·g−1, respectively. The discharge capacities of the (Fe0.5Ni0.5)9S8 powders for the 2nd and 100th cycle were 530 and 527 mA·h·g−1, respectively, and their corresponding capacity retention measured from the 2nd cycle was 99%. The (Fe0.5Ni0.5)9S8 powders had high initial discharge and charge capacities at a low current density of 0.1 A·g−1, and the reversible discharge capacity decreased slightly from 568 to 465 mA·h·g−1 as the current density increased from 0.1 to 5.0 A·g−1. The synergetic effect of the novel yolk–shell structure and the multicomponent sulfide composition of the (Fe0.5Ni0.5)9S8 powders resulted in excellent sodium-ion storage performance.

关键词： metal sulfide multicomponent sulfide yolk–shell sodium-ion batteries spray pyrolysis

Rational design and synthesis of hierarchically structured SnO2 microspheres assembled from hollow porous nanoplates as superior anode materials for lithium-ion batteries

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Nano Research 2018年第3期11卷 1301-1312页

作者： Gi Dae Park Yun chan Kang Department of Materials Science and Engineering Korea University Anam-Dong Seongbuk-Gu Seoul 136-713 Republic of Korea

Herein, hierarchically structured SnO2 microspheres are designed and synthesized as an efficient anode material for lithium-ion batteries using hollow SnO2 nanoplates. Three-dimensionally ordered macroporous （3-DOM） SnOx-C microspheres synthesized by spray pyrolysis are transformed into hierarchically structured SnO2 microspheres by a two-step post-treatment process. Sulfidation produces hierarchically structured SnS-SnS2-C microspheres comprising tin sulfide nanoplate and carbon building blocks. A subsequent oxidation process produces SnO2 microspheres from hollow SnO2 nanoplate building blocks, which are formed by Kirkendall diffusion. The discharge capacity of the hierarchically structured SnO2 microspheres at a current density of 5 Ag^-1 for the 600th cycle is 404 mA·h·g^-1. The hierarchically structured SnO2 microspheres have reversible discharge capacities of 609 and 158 mA·h·g^-1 at current densities of 0.5 and 30 Ag^-1, respectively. The ultrafine nanosheets contain empty voids that allow excellent lithium-ion storage performance, even at high current densities.

关键词： Kirkendall diffusion nanoplate tin oxide lithium-ion batter spray pyrolysis

Numerical characteristics of the full operator hybrid simulation method

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Earthquake Engineering and Engineering Vibration 2011年第3期10卷 453-463页

作者： Chung-chan Hung Yong-Song Chen Department of Civil Engineering Central University （NCU） Chinese Taipei Department of Mechanical Engineering Chung Cheng University （NCCU） Chinese Taipei

The full operator method （FOM） has been proposed to overcome some of the shortcomings of the commonly used operator splitting method （OSM）. In particular, the FOM is improved by increasing the accuracy of both the predictor and corrector using the estimated tangent stiffness of the tested structure. The numerical characteristics of the FOM, including stability and accuracy, are investigated in this study. It is shown that FOM is conditionally stable. The stability and accuracy characteristics are dependent on the accuracy of the estimated tangent stiffness and the parameters associated with the acceleration variation in the time-stepping integration method. Mass-spring systems with different types of nonlinearity, including hardening, stiffening, and softening behavior, are used to evaluate the performance of the FOM. It is found that the FOM can capture these types of nonlinearity with satisfactory accuracy. Using a prototype 12-story composite coupled wall system, the influences of the strong nonlinearity of the system as well as the displacement control errors from hydraulic actuators on the performance of the FOM are explored. The results show that the FOM is capable of generating reasonably accurate results despite the presence of strong structural nonlinearity and displacement control errors.

关键词： hybrid simulation tangent stiffness numerical characteristic composite coupled wall system collapse behavior nonlinear behavior

Improving the wind and temperature measurements of an airborne meteorological measuring system

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2012年第10期13卷 723-746页

作者： Stephen FOSTER P.W.chan Aventech Research Inc. BarrieON L4N 2E3Canada Hong Kong Observatory KowloonHong KongChina

The Aircraft Integrated Meteorological Measuring System 20 Hz(AIMMS-20) has been used by the Hong Kong Observatory(HKO),China in data collection for tropical cyclone situations over the South China Sea and windshear and turbulence measurement at the Hong Kong International Airport(HKIA).This paper discusses possible methods for further enhancing the quality of the wind and temperature measurements from the *** wind measurement,the enhancement methods include:error modelling of the accelerometer(e.g.,bias offset and cross-axis rate sensitivity),global positioning system(GPS) phase lag consideration,better representation of the inertial measurement unit(IMU) velocity based on the GPS velocities and considering their location differences,consideration of the slower update of GPS velocity,and wing *** temperature measurement,the methods include the consideration of the temperature sensor response and the sensor housing *** results of typical flights using AIMMS-20 show that the accuracy of the wind and temperature data could be improved by 20%-30%.Though the discussion in the present paper is related mainly to a specific meteorological measuring system on a particular aircraft,the techniques so employed should be a useful reference for similar systems installed on other aircraft.

关键词： Airborne meteorological measurements Kalman filter Comparison with radiosonde measurement

An electrochemical method for evaluating the resistance to cathodic disbondment of anti-corrosion coatings on buried pipelines

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Journal of University of Science and Technology Beijing 2007年第5期14卷 414-419页

作者： chan Li Bei Cao Yinshun Wu Materials Science and Engineering School University of Science and Technology Beijing Beijing 100083 China

Methods for evaluating the resistance to cathodic disbondment （RCD） of anti-corrosion coatings on buried pipelines were reviewed. It is obvious that these traditional cathodic disbondment tests （CDT） have some disadvantages and the evaluated results are only simple figures and always rely on the subjective experience of the operator. A new electrochemical method for evaluating the RCD of coatings, that is, the potentiostatic evaluation method （PEM）, was developed and studied. During potentiostatic anodic polarization testing, the changes of stable polarization current of specimens before and after cathodic disbonding （CD） were measured, and the degree of cathodic disbondment of the coating was quantitatively evaluated, among which the equivalent cathodic disbonded distance AD was suggested as a parameter for evaluating the RCD. A series of testing parameters of the PEM were determined in these experiments.

关键词： buried pipeline anti-corrosion coating resistance to cathodic disbondment (RCD) potentiostatic evaluation method(PEM) fusion bonded epoxy (FBE) three-layer polyethylene (3PE)

Global collaboration of eye research--personal experience

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International Journal of Ophthalmology(English edition) 2024年第6期17卷 985-990页

作者： Chi-Chao chan Laboratory of Immunology National Eye InstituteNational Institutes of HealthBethesdaMD 20892-1858USA Zhongshan Ophthalmic Center Sun Yat-sen UniversityGuangzhou 5410060Guangdong ProvinceChina

On December 9,2023,I was privileged to be honored and participate in the *** Chao chan Symposium on Global Collaboration of Eye Research as the Global Eye Genetic Consortium(GEGC)session,which was held in the 16th Congress of the Asia-Pacific Vitreo-Retina Society(APVRS)in Hong *** with my talk on“Global collaboration of eye research:personal experience”,other prominent international speakers provided their own perspectives on opportunities for networking,collaboration,and exchange of ideas with global leaders and experts in ophthalmic practice,research,and education.

关键词： speakers collaboration Global

Establishment of chronic hepatitis C virus infection:Translational evasion of oxidative defence

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World Journal of Gastroenterology 2014年第11期20卷 2785-2800页

作者： Shiu-Wan chan Faculty of Life Sciences The University of ManchesterManchester M13 9PTUnited Kingdom

Hepatitis C virus(HCV)causes a clinically important disease affecting 3%of the world *** is a single-stranded,positive-sense RNA virus belonging to the genus Hepacivirus within the Flaviviridae *** virus establishes a chronic infection in the face of an active host oxidative defence,thus adaptation to oxidative stress is key to virus *** a small RNA virus with a limited genomic capacity,we speculate that HCV deploys a different strategy to evade host oxidative *** of counteracting oxidative stress,it utilizes oxidative stress to facilitate its own *** is the first step in the replication of a plus strand RNA virus so it would make sense if the virus can exploit the host oxidative defence in facilitating this very first *** is particularly true when HCV utilizes an internal ribosome entry site element in translation,which is distinctive from that of cap-dependent translation of the vast majority of cellular genes,thus allowing selective translation of genes under conditions when global protein synthesis is ***,we were the first to show that HCV translation was stimulated by an important prooxidant-hydrogen peroxide in hepatocytes,suggesting that HCV is able to adapt to and utilize the host antiviral response to facilitate its own translation thus allowing the virus to thrive under oxidative stress condition to establish *** how HCV translation is regulated under oxidative stress condition will advance our knowledge on how HCV establishes *** chronicity is the initiator step in disease progression this will eventually lead to a better understanding of pathogenicity,which is particularly relevant to the development of anti-virals and improved treatments of HCV patients using anti-oxidants.

关键词： Hepatitis C virus Oxidative stress Hydrogen peroxide Translation Internal ribosome entry site Chronicity Persistence

Synthesis of[3,3'-Di-sec-butyl-4'-(2-dimethylaminoethoxy)-biphenyl-4-yl-oxy]acetic Acid

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Chinese Journal of Chemistry 2014年第3期32卷 276-279页

作者： Mengyang chang Chiehkai chan Department of Medicinal and Applied Chemistry Kaohsiung Medical UniversityKaohsiung 807TaiwanChina

A modified synthetic route of[3,3'-di-sec-butyl-4'-(2-dimethylaminoethoxy)biphenyl-4-yloxy]acetic acid(1)with high total yield of 44%from biphenyl-4,4'-diol(2)is described.

关键词： Claisen rearrangement Suzuki-Miyaura cross-coupling biphenyl skeleton

Investigation of cubic Pt alloys for ammonia oxidation reaction

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Nano Research 2020年第7期13卷 1920-1927页

作者： Yat Tung chan Kumar Siddharth Minhua Shao Department of Chemical and Biological Engineering The Hong Kong University of Science and TechnologyClear Water BayKowloonHong KongChina

As a promising fuel candidate,ammonia has been successtully used as anode feed in alkaline fuel ***,current technology in catalysts for ammonia electro-oxidation reaction(AOR)with respect to both cost and performance is inadequate to ensure large scale commercial application of direct ammonia fuel *** studies found that alloying Pt with different transition metals and controlling the morphology of catalysts can improve the AOR activity,and thus potentially can solve the cost ***,(100)-terminated Pt-M nanocubes(M=3d-transition metals Fe,Co,Ni,Zn)are synthesized via wet-chemistry method and their catalytic activities toward AOR are *** addition of Fe,Co,Ni and Zn elements can enhance the AOR activity due to decrease in oxophilicity of platinum and bifunctional ***-Zn exhibits the maximum mass activity and specific ativity with values of 0.41 A/mgpt and 169 mA/cm2 that are 1.6 and 1.8 times higher than Pt nanocubes,***-Fe,Pt-Co and PI-Ni nanocubes also ilustrate higher mass and specific activities compared to Pt nanocubes.

关键词： ammonia oxidation reaction electrocatalysts Pt-3d transition metal nanocubes OH adsorption

Building an e-Portfolio with a learning plan centric approach

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Journal of Zhejiang University-Science C(Computers and Electronics) 2012年第1期13卷 37-47页

作者： Lam-for KWOK Ka-shing chan Department of Computer Science City University of Hong Kong

A portfolio records achievements in the personal growth process. A personal development e-Portfolio assists an individual in planning his/her development path and reflecting upon his/her own learning. In this article, we propose an approach to constructing a personal development portfolio. An abstract information model is presented to support such a portfolio. The information model is proposed based upon and according to IMS standards. The use of this approach is illustrated by way of a prototype e-Portfolio system. The usage scenario and limitations of such a portfolio are also discussed.

关键词： E-Portfolio Educational technology system Lifelong learning