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Nano Research 2014年第3期7卷 410-417页

作者： Fulin Zheng wing-Tak wong Ka-Fu yung Department of Applied Biology and Chemical Technology The Hong Kong Polytechnic University Hung Hom Hong Kong SAR China

A facile design of Pt nanostructures from submonolayer to monolayer has been realized by ion adsorption-in situ electrochemical reduction on Au nanoparticles supported on multiwall carbon nanotubes （CNTs）. The as prepared Au@Pt/CNTs catalysts display coverage-specific electrocatalysis. Au@Pt/CNTs with low Pt coverage is inactive towards methanol oxidation whereas it oxidizes formic acid effectively through a direct pathway with mass specific activity 90 times that of a commercial Pt/C catalyst. Due to its inertness to methanol, it shows high performance in the oxygen reduction reaction （ORR） with high methanol tolerance. In contrast, simply increasing the Pt coverage to above 40% switches the formic acid oxidation process to both direct and indirect catalytic pathways, and also results in high methanol oxidation activity.

关键词： electrocatalysis platinum submonolayer fuel cell

Taylor Dispersion of Contaminants by Dual-peak Spectral Random waves

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China Ocean Engineering 2019年第5期33卷 537-543页

作者： HUAng Guo-xing Adrian wing-Keung LAw GUO Xiao-meng State Key Laboratory of Coastal and Offshore Engineering Dalian University of Technology Dalian 116024 China School of Civil and Environmental Engineering and Environmental Process Modelling Centre Nanyang Environment and Water Resources Institute (NEWRI) Nanyang Technological University Singapore 639798 Singapore State Key Laboratory of Hydrology-water Resources and Hydraulic Engineering Nanjing Hydraulic Research Institute Nanjing 210029 China

Recent extensive and important studies have provided detailed information and compelling evidence on how the presence of waves influences the vertical diffusivity/dispersivity in the coastal environment, which can affect various water quality considerations such as the distribution of suspended sediments in the water column as well as the potential of eutrophication. Comparatively, how the presence of waves influences the horizontal diffusivity/dispersivity has received only scant attention in the literature. Our previous works investigated the role played by the Taylor mechanism due to the wave-induced drift profile which leads to the longitudinal dispersion of contaminants in the horizontal direction, under regular sinusoidal waves and random waves with single-peak spectra. Natural waves in the coastal environment, however, often possess dual-peak spectra, comprising both higher frequency wind waves and lower frequency swells. In this study, the Taylor dispersion of contaminants under random waves with dual-peak spectra is examined through analytical derivation and numerical calculations. The effects of various dual-peak spectral parameters on the horizontal dispersion, including the proportion of lower frequency energy, peak frequency ratio and spectral shape parameter, are investigated. The results show that the relative energy distribution between the dual peaks has the most significant effect. Compared with single-peak spectra with equivalent energy, the Taylor dispersion with dual-peak spectra is stronger when the lower frequency is close to the peak frequency of the single-peak spectrum, and weaker with the higher frequency instead. Thus, it can be concluded that with a dual-peak wave spectrum, wind-dominated seas with higher frequency lead to stronger dispersion in the horizontal direction than swell-dominated seas with lower frequency.

关键词： Taylor dispersion dual-peak spectrum random waves

Luminescent cyclometalated iridium(Ⅲ) dipyridoquinoxaline indole complexes as biological probes

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Science China Chemistry 2010年第10期53卷 2091-2098页

作者： LO Kenneth Kam-wing LEUng Arthur Ho-Hon Department of Biology and Chemistry City University of Hong Kong

Four luminescent cyclometalated iridium(Ⅲ) dipyridoquinoxaline complexes appended with an indole moiety [Ir(N^C)2(N^N)] (PF6) (HN^C = 2-phenylpyridine, Hppy; N^N = 2-(N-(2-(indole-3-acetamido)ethyl)aminocarbonyl)dipyrido[3,2-f:2′,3′-h]quinox- aline, dpqC2indole (1a), N^N = 2-(N-(6-(indole-3-acetamido)hexyl)aminocarbonyl)dipyrido[3,2-f:2′,3′-h]quinoxaline, dpqC6indole (1b); HN^C = 7,8-benzoquinoline, Hbzq, N^N = dpqC2indole (2a), N^N = dpqC6indole (2b)) have been synthesized and characterized. Upon irradiation, all the complexes displayed moderately intense and long-lived luminescence under ambient condi-tions and in 77 K glass. On the basis of the photophysical data, the emission of the complexes has been assigned to an excited state of triplet metal-to-ligand charge-transfer (3MLCT) ((dπ(Ir)→π*(N^N)) character. Cyclic voltammetric studies revealed indole-based and iridium-based oxidations at ca. +1.10 V and +1.24 V vs. SCE, respectively, and ligand-based reductions at ca. -1.07 to-2.29 V vs. SCE. The interactions of the complexes with an indole-binding protein, bovine serum albumin (BSA), have been examined by emission titrations.

关键词： binding indole iridium luminescence probes

Globalization,National Identity,and Citizenship Education:China’s Search for Modernization and a Modern Chinese Citizenry

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Frontiers of Education in China 2013年第4期8卷 596-627页

作者： wing-wah LAw Faculty of Education The University of Hong KongHong KongChina

Since the early 20th century,numerous scholars have proposed theories and models describing,interpreting,and suggesting the development paths countries have taken or should *** of these,however,can fully explain China’s efforts,mainly through education and citizenship education,to modernize itself and foster a modern citizenry since the late 19th *** article traces and examines these efforts through a reflective and critical analysis of such public texts as official policy documents,curriculum standards,and related commentaries,and reveals three major ***,China’s leaders have advanced different views of and approaches to development and citizenship in response to changing domestic and global ***,the Chinese state determines China’s development course,defines its national identity and citizenry,and selects its nation-building ***,the Chinese state’s growing desire for national rejuvenation in an increasingly competitive,globalized world in the 21st century mandates an important education mission that its citizenship education be politically and ideologically open and accommodative,and help students develop global,national and local identities and function as active,responsible citizens of a multileveled,multicultural *** article furthers academic understanding of how China’s education responds to economic,political,and social demands and shapes students’multiple identities in a global age.

关键词： globalization national identity citizenship education China

Constructionist Learning in School Mathematics:Implications for Education in the Fourth Industrial Revolution

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ECNU Review of Education 2023年第2期6卷 328-339页

作者：吴谌蓝曾咏琪 The Chinese University of Hong Kong China

Highlights Amid rapid technological development in the Fourth Industrial Revolution,this article engages with an important question,especially in the context of science,technology,engineering,and mathematics(STEM)educ... 详细信息

关键词： 3D printing constructionism Fourth Industrial Revolution mathematics education STEM education

Performance of ground penetrating radar in root detection and its application in root diameter estimation under controlled conditions

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Science China Earth Sciences 2016年第1期59卷 145-155页

作者： yEUng Shan wing yAN wai Man HAU Chi Hang Billy Department of Civil Engineering The University of Hong Kong Kadoorie Institute The University of Hong Kong

A plant is stabilized by its root system. In congested urban cities such as Hong Kong, ground trenching is frequently seen due to the installation of utility lines along the roadside. Soil nailing, which involves soil coring in slopes, is a common solution to improve the slope stability. However, both activities inevitably pose a risk to the integrity of any root sys- tems present, and thus reduce the root anchorage. To prevent or minimize such damage, a careful design of the excava- tion/drilling location is of prime importance. Ground penetrating radar （GPR） provides a non-destructive method for locating roots by examining the contrast between the dielectric properties of the roots and the surrounding soil. To examine the perfor- mance of GPR and promote its use in Hong Kong, a test bed was prepared using local materials to create a controlled envi- ronment in which to conduct a series of systematic tests evaluating the performance of a 900 MHz GPR. The reflected radar- grams were subject to the influence of the following factors： size and depth of roots, horizontal distance between roots, and contrast between the root and soil water content. Correlations between root size and a number of waveform parameters were also explored. Limiting values for root size, root embedded depth, horizontal separation distance between roots, and water content contrast between root and soil were obtained. A significant correlation was found between the root diameter and time travel parameter T2 （p〈0.001, t=0.795）. Because GPR root detection is highly site-specific, this study provides a local refer- ence for GPR performance in the Hong Kong environment. The findings demonstrate that the 900 MHz GPR is applicable in Hong Kong for the detection of main roots.

关键词： GPR Radar profile Root detection Root water content Root size

Surface thermophysical properties on the potentially hazardous asteroid (99942) Apophis

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Research in Astronomy and Astrophysics 2017年第7期17卷 67-76页

作者： Liang-Liang yu Jianghui Ji wing-Huen Ip Space Science Institute Macao University of Science and Technology CAS Key Laboratory of Planetary Sciences Purple Mountain ObservatoryChinese Academy of Sciences Institute of Astronomy National Central University

we investigate the surface thermophysical properties（thermal emissivity, thermal inertia,roughness fraction and geometric albedo） of asteroid（99942） Apophis, using the currently available mid-infrared observations from CanariC am on Gran Telescopio CANARIAS and far-infrared data from PACS on Herschel, based on the Advanced Thermophysical Model. we show that the thermal emissivity of Apophis should be wavelength dependent from 8.70 μm to 160 μm, and the maximum emissivity may appear around 20 μm, similar to that of Vesta. Moreover, we further derive the thermal inertia,roughness fraction, geometric albedo and effective diameter of Apophis within a possible 1σ scale of Γ = 100（-52）^（＋100）＋Jm^（-2）s^-0.5K^-1, fr = 0.78~1.0, pv = 0.286（-0.026）^（＋0.030） and D（eff） = 378（-25）^（＋19）m, and 3σscale of Γ = 100（-100）^（＋240）Jm^（-2）s^-0.5 K^-1, fr = 0.2~1.0, pv = 0.286（-0.029）^（＋0.039） and D（eff） = 378（-29）^（＋27） m. The derived low thermal inertia but high roughness fraction may imply that Apophis could have regolith on its surface, where stronger space weathering but weaker regolith migration has happened in comparison with asteroid Itokawa. Our results show that small-size asteroids could also have fine regolith on the surface, and further infer that Apophis may have been delivered from the Main Belt by the yarkovsky effect.

关键词： techniquest hermal infrared -- variables thermal inertia -- asteroid individual (99942)Apophis

A Revisit of the Phobos Events

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空间科学学报 2011年第2期31卷 150-153页

作者： wing-Huen Ip Institutes of Astronomy and Space Sciences National Central UniversityTaiwan Institute of Space Science Macao University of Science and TechnologyMacao

The magnetic field disturbances detected by the Phobos-2 spacecraft in 1989 have been suggested to be caused by a ring of dust and/or gas emitted from the Martian moon,*** physical nature of these"Phobos events"is examined using results from related investigations over the last twenty *** is concluded that there is no clear evidence at present to support the association of magnetic field disturbances in the solar wind with *** situation will be further clarified taking advantage of the multi-spacecraft observations of the yinghuo-1(yH-1),Mars Express and MAVEN missions beginning in *** is expected that many novel features of solar wind interaction with Phobos(and possibly also Deimos) itself will also be revealed.

关键词： Mars Solar wind interaction Phobos moon Dust rings yH-1

Anterior perineal hernia after anterior exenteration

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Asian Journal of Urology 2017年第4期4卷 253-255页

作者： Ka wing wong Terence Chun-ting Lai Ada Tsui-lin ng Brian Sze-ho Ho James Hok-leung Tsu Chiu Fung Tsang w.K.Ma Ming Kwong yiu Division of Urology Department of SurgeryQueen Mary HospitalUniversity of Hong KongHong KongChina

Perineal hernia is a rare complication of anterior *** reported this complication after an anterior exenteration for bladder cancer with bleeding complication requiring packing and second-look *** approach is a simple... 详细信息

关键词： Perineal hernia Anterior exenteration Bladder cancer Mesh repair

AN　UNUSUAL　CASE　OF　ASyMPTOMATIC　APLASTIC　RENAL　DySPLASIA

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Chinese Medical Sciences Journal 1995年第2期10卷 119-121页

作者： LouisTsun-CheungChow wing-HingChow DepartmentofAnatomicalandCellularPathology PrinceofWalesHospitalShatinHongKong DepartmentofMedicine GranthamHospitalHongKong

The postmortem examination of a 59-year-old man who had suffered from acute abdominal pain for two days revealed that the cause of death was peritonitis secondary to perforated peptic ulceration. During examination,it was found that the urinary tract was abnormal. Here, we report a postmortem finding of aplastic renal dysplasia of the kidney and malformation of the urinary tract.

关键词： renal dysplasia kidney aplasia