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An Indentation Method for Nanoprecision Measurement of Diamond Tool Edge Radius

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厦门大学学报（自然科学版） 2002年第S1期41卷 98-99页

作者： X P Li M Rahman K Liu K S Neo C C chan Department of Mechanical Engineering National University of SingaporeDepartment of Mechanical Engineering National University of SingaporeDepartment of Mechanical Engineering National University of SingaporeDepartment of Mechanical Engineering National University of SingaporeDepartment of Mechanical Engineering National University of Singapore SingaporeSingaporeSingaporeProcess Technology Division Gintic Institute of Manufacturing Technology Si ngaporeSingaporeSingapore

In ductile mode cutting of brittle materials using di amond tools, such as ductile cutting of silicon and quartz for wafer fabrication , one of the key conditions for achieving ductile chip formation is to get the r ight ratio of tool cutting edge radius to the undeformed chip thickness. It has been shown that the undeformed chip thickness has to be in the order of nanomete rs and that the tool cutting edge radius has to be smaller than the undeformed c hip thickness. Therefore, nanoprecision measurement of diamond cutting tools has become a key issue for ductile mode cutting of brittle materials. In this paper , a non-destructive nanoprecision measurement method for diamond tool cutting e dge radius is presented. The basis of the method is that the exact profile of th e tool cutting edge can be perfectly copied by indenting the tool cutting edge o n the surface of a rigid-perfect plastic material, and that the copy of the pro file can be measured at nanoprecision level. Ideally, the first aspect of th e method is to make a perfect copy of the tool cutting edge profile by indentati on on the surface of a rigid-perfect plastic material which has no elastic spri ng back, so that a true copy of the tool cutting edge is maintained for subseque nt measurement. Since no rigid-perfect plastic material can be found in realit y, actual materials of rigid-elastic-plastic nature have to be used for the in dentation in the measurement method, and the material elastic error compensation coefficients have to be determined to cancel out the effect of elastic spring b ack. For the minimization of error compensation, criteria for the selection of t he optimal materials for the indentation measurement are found to be: 1) high ri gidity and high density, 2) large Young’s elastic modulus, and 3) low yield strength. One of such materials identified is copper. The second aspect of the method is to measure the radius of the indented profile on the surface of the ma terial. This can be ach

关键词： nanoprecision measurement indentation diamond tool cutting edge radius ductile mode cutting

Mercury accumulation,distribution,and isotopic composition in tissues of the Collared Scops Owl(Otus lettia)

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Acta Geochimica 2023年第4期42卷 637-647页

作者： Dongya Jia Kang Luo Zhidong Xu Xiaohang Xu chan Li Hongmei Wu Dawei Wang Hui Ye Gaoen Wu Zhuo Chen Guangle Qiu School of Chemistry and Materials Science Guizhou Normal UniversityGuiyang 550001China State Key Laboratory of Environmental Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China College of Resources and Environmental Engineering Guizhou UniversityGuiyang 550025China School of Ecology and Environmental Science Yunnan UniversityYunnan 650091China University of Chinese Academy of Sciences Beijing 100049China School of Public Health Guizhou Medical UniversityGuiyang 550025China College of Ecology and Environment Hainan UniversityHainan 570228China

Mercury is a ubiquitous contaminant known to accumulate in wildlife,particularly bird species at higher trophic *** of tissue-specific Hg distributions aids our understanding of Hg bioaccumulation in *** this study,one adult and three juvenile Collared Scops Owls(Otus lettia)were studied to elucidate the bioaccumulation of Hg in body *** tissues and organs(feathers,nails,heart,liver,gizzard,and muscle),as well as gastric contents,were examined for total Hg(THg)and methylmercury(MeHg)contents,Hg isotopic compositions including mass-dependent fractionation(MDF;δ202Hg)and mass-independent fractionation(MIF;Δ199Hg andΔ201Hg),and C(δ13C)and N(δ15N)isotopic ***-specific THg and MeHg concentrations in the adult were in the ranges of 150–1360 ng/g and17–1060 ng/g,and lower in the juveniles at 91–419 ng/g and 67–350 ng/g,***δ^(202)Hg values in the adult were strongly negative at-1.75‰±0.17‰compared with the juveniles at-0.99‰±0.25‰.The adult exhibited lower MIF values than the juveniles,at0.23‰±0.07‰forΔ^(199)Hg and 0.2‰±0.11‰forΔ^(201)Hg,comparedwith0.81‰±0.09‰and0.66‰±0.07‰,*** lower adult MDF and MIF values suggest that the adult tended to accumulate negative Hg isotopes but the juvenile's positive Hg *** between adult and juvenile tissue Hg concentrations indicate that metabolic processes play an important role in Hg accumulation.

关键词： Mercury Methylmercury Mass-dependent fractionation Mass-independent fractionation Tissue Terrestrial bird

A Distributed Multimedia Conferencing System

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A Distributed Multimedia Conferencing System

计算机，通信，控制与电力工程国际会议

作者： Jim M.ng Edward chan Horace H.S.Ip Peter H.H.Tsang K.Y.Kwok Y.K.Lee City Polytechnic of Hong Kong Department of Computer Science 83 Tat Chee Ave. Kowloon Hong Kong

In this paper,we present the design of a desktop multimedia conferencing system,called Nebula,built with a distributed conference control infrastructure with fault tolerance *** system provides for considerable flexibility in conferencing facilities:it supports three different modes of floor control passing and switching between these modes during a *** can join a conference in various ways,with selection of chairperson according to seniority defined in the agenda *** handle the concurrency problem,only the floor holder can modify shared data in the public windows. Each conferee holds a copy of shared data and only update operations are sent so as to improve response time and minimize network traffic.A simple and well defined Application User Interface(API) is provided and a number of multimedia applications has been developed using the API.

关键词： API A Distributed Multimedia Conferencing System session

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言几又广州K11黑金旗舰店

现代装饰 2018年第10期 86-91页

作者：陈峻佳 Derek ng Jacky Wan Leon Zhang Carol chan Derrick Leung 廖贵衡峻佳设计公司

言几又广州K11黑金旗舰店毗邻广州地标东塔,坐落于K11艺术型商业中心,作为言几又首家扎根广州的旗舰店,设计师为其定制设计了一个极具故事性和话题感的艺术主题空间,以富有隐喻和启发性的空间故事串起场所记忆与品牌内涵。突破言几又惯... 详细信息

言几又广州K11黑金旗舰店毗邻广州地标东塔,坐落于K11艺术型商业中心,作为言几又首家扎根广州的旗舰店,设计师为其定制设计了一个极具故事性和话题感的艺术主题空间,以富有隐喻和启发性的空间故事串起场所记忆与品牌内涵。突破言几又惯常的设计表达,设计师以“黑洞·引力场”作为创意灵感,衍生出K11言几又的终端设计。黑色的深邃叠加多维主题空间,配以互动式谜题设计,以隐喻式的空间强烈地吸引来访者开启创新的探索之旅,呈现出独特的设计美学。

关键词：旗舰店广州金定制设计商业中心品牌内涵设计表达终端设计

Analysis of Neuroregenerative Effects By Gastrodia Elata Growing In Four Different Areas On Human Neuronal BE-2（C） Cells By Real Time Reverse Transcription·Polymerase Chain Reaction

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Analysis of Neuroregenerative Effects By Gastrodia Elata Gro...

第十四届全国中药和天然药物学术研讨会

作者： chan Tsz Chun Tang Yat Man Calvin Sin Kyle Hao Liu Michelle CH ng Kei Fan Daniel Mok Foo Tim Chau Daniel Man Yuen Sze The Hong Kong Polytechnic University

＜正＞Introduction Neurodegenerative diseases have been a great concern of the *** elata can be a new way out for neurodegenerative diseases as it had neuroprotective and neuroregenerative *** project will analyze the...

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Effects of Gastrodia elata Blume from Different Origins in China in an Experimental Parkinson’s Disease Cell Line Model

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Effects of Gastrodia elata Blume from Different Origins in C...

第十四届全国中药和天然药物学术研讨会

作者： chan Man Wai Tang Yat Man Calvin Sin Kyle Hao Liu Michelle CH ng Kei Fan Daniel Mok Foo Tim Chau Daniel Man Yuen Sze The Hong Kong Polytechnic University

＜正＞Introduction Parkinson’s disease（PD）is one of the most common neurodegenerative diseases in the *** is suggested that oxidative stress caused by excessive production of reactive oxygen species（ROS）and subse...

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Evaluation Of The Neuroprotective Effect Of Tianma From Two Different Sources In Human Neural BE（2）-C Cell With 6-OHDA-lnduced Injury Through Real-Time Polymerase Chain Reaction

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Evaluation Of The Neuroprotective Effect Of Tianma From Two ...

第十四届全国中药和天然药物学术研讨会

作者： chan Man Wai Tang Yat Man Calvin Sin Kyle Hao Liu Michelle CH ng Kei Fan Daniel Mok Foo Tim Chau Daniel Man Yuen Sze The Hong Kong Polytechnic University

＜正＞Introduction Neurodegenerative diseases have been affecting over 25 million people *** there are medicines and therapies,there is still lack of complete treatment of the *** of using tianma,a traditional Chinese...

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GC-MS/MS法测定大米、砀山梨及娃娃菜中胺鲜酯的残留量

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食品安全导刊 2024年第1期 77-80页

作者：朱晓蕾王明明梅婵庄件兵苏静萍董耀江苏省生产力促进中心江苏南京210001

建立了一种适用于气相色谱-串联质谱联用仪测定蔬菜、水果、粮谷中胺鲜酯残留量的分析方法。试样经过乙腈提取,QuEChERS dSPE EMR-Lipid(大米试样)、PSA、C_(18)及GCB(砀山梨和娃娃菜试样)净化后,以HP-5MS色谱柱进行分离,在电子轰击离... 详细信息

建立了一种适用于气相色谱-串联质谱联用仪测定蔬菜、水果、粮谷中胺鲜酯残留量的分析方法。试样经过乙腈提取,QuEChERS dSPE EMR-Lipid(大米试样)、PSA、C_(18)及GCB(砀山梨和娃娃菜试样)净化后,以HP-5MS色谱柱进行分离,在电子轰击离子源、多反应监测模式下检测大米、砀山梨和娃娃菜中胺鲜酯的残留量,基质外标法定量。结果表明,胺鲜酯浓度在2~200 ng·mL^(-1)时,线性关系良好,相关系数(r)均在0.9999以上,在3个不同浓度添加水平下,大米胺鲜酯的回收率为92.4%~105.0%,砀山梨胺鲜酯的回收率为84.0%~90.0%,娃娃菜胺鲜酯的回收率为93.6%~112.0%,大米的方法检出限为0.002 mg·kg^(-1),定量限为0.004 mg·kg^(-1);砀山梨和娃娃菜的检出限为0.001 mg·kg^(-1),定量限为0.002 mg·kg^(-1)。方法精密度试验的相对标准偏差在5%以内。该方法适用于蔬菜、水果、粮谷中胺鲜酯的定性和定量测定。

关键词：气相色谱-串联质谱联用仪胺鲜酯残留量

Synthesis, Characterization and Photochromic Studies of Cyclometalated Iridium（Ⅲ） Complexes Containing Spironaphthoxazine Moiety

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Synthesis, Characterization and Photochromic Studies of Cycl...

中国化学会第十届全国无机化学学术会议

作者： Jie Liu Alan Kwun-Wa chan Maggie ng Eugene Yau-Hin Hong Nathan Man-Wai Wu Zuoyi Li Huilan Zhang Lixin Wu Vivian Wing-Wah Yam State Key Laboratory of Supramolecular Structure and Materials and College of Chemistry Jilin University Institute of Molecular Functional Materials (Areas of Excellence Scheme University Grants Committee (Hong Kong) and Department of Chemistry The University of Hong Kong Institute of Molecular Functional Material (Areas of Excellence Scheme University Grants Committee (Hong Kong)and Department of Chemistry The University of Hong Kong

A series of cyclometalated iridium（Ⅲ） complexes has been designed and synthesized, and their photophysical, photochromic and electrochemical properties have been studied. The X-ray crystal structure of complex 2 has been determined. The emission properties of the complexes have been shown to be readily perturbed through the modification of the electronic properties of the phenylpyridine ligand, leading to their tunable optical properties[1] for photochromic and material applications[2].

关键词： luminescence photochromism iridium spirooxazine