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Deformation Analysis of Micro/Nano Indentation and diamond Grinding on Optical Glasses

Chinese Journal of Mechanical Engineering 2012年第3期25卷 411-418页

作者： ZHAO Qingliang ZHAO Lingling GUO Bing STEPHENSIN david CORBETT John School of Mechatronics Engineering Harbin Institute of TechnologyHarbin 150001China Materials Department Cranfield UniversityCranfieldBedford MK43 OALUK School of Applied Sciences Cranfield UniversityCranfieldBedford MK43 OALUK

The previous research of precision grinding optical glasses with electrolytic in process dressing （ELID） technology mainly concentrated on the action of ELID and machining parameters when grinding, which aim at generating very ＂smoothed＂ surfaces and reducing the subsurface damage. However, when grinding spectrosil 2000 and BK7 glass assisted with ELID technology, a deeply comparative study on material removal mechanism and the wheel wear behaviors have not been given yet. In this paper, the micro/nano indentation technique is initially applied for investigating the mechanical properties of optical glasses, whose results are then refereed to evaluate the machinability. In single grit diamond scratching on glasses, the scratching traces display four kinds of scratch characteristics according to different material removal modes. In normal grinding experiments, the result shows BK7 glass has a better machinability than that of spectrosil 2000, corresponding to what the micro/nano indentation vent revealed. Under the same grinding depth parameters, the smaller amplitude of acoustic emission （AE） raw signals, grinding force and grinding force ratio correspond to a better surface quality. While for these two kinds of glasses, with the increasing of grinding depth, the variation trends of the surface roughness, the force ratio, and the AE raw signals are contrary, which should be attributed to different material removal modes. Moreover, the SEM micrographs of used wheels surface indicate that diamond grains on the wheel surface after grinding BK7 glass are worn more severely than that of spectrosil 2000. The proposed research analyzes what happened in the grinding process with different material removal patterns, which can provide a basis for producing high-quality optical glasses and comprehensively evaluate the surface and subsurface integrity of optical glasses.

关键词： optical glasses micro/nano indentation single grit diamond scratching material removal mode surface integrity electrolytic in process dressing (ELID)

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Properties of SN Ia progenitors from light curves and spectra

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Frontiers of physics 2013年第2期8卷 144-167页

作者： P. Hoflich P. Dragulin J. Mitchell B. Sadler T. diamond C. Gerardy Department of Physics Florida State University Talahassee USA FL 32306 Department of Physics Astronomy Clemson University Clemson USA SC 29634

With recent advances in theory and observations, direct connections emerge between the progenitors of Type Ia Supernovae （SNe Ia） and the observed light curves and spectra. A direct link is important for our understanding of the supernovae physics, the diversity of SNe Ia and the use of SNe Ia for high-precision cosmology because the details of the explosion depends sensitively on the initial conditions and the explosion scenario（s） realized in nature. Do SNe Ia originate from SD- or DD systems, and do they lead to Mcu mass explosions or dynamical mergers？ Does the statistical distribtion of SNe Ia depend on their environment which can be expected to change with redshift？ In this contribution, we will exam from the theoretical point of view the tell-tails for this connection, their consistency with the observations, and future directions. In a first section, we present the physics of the explosion, light curves and spectral formation in a nutshell to help understanding the connection. For details of the progenitor evolution and explosion physics, we refer to reviews and the other contributions in this issue. Each of the topical sections starts with a brief general review followed by a more detailed discussion of specific results. Because the youth of the field, some bias is unavoidable towards results obtained within our collaborations （and FSU）. The imprint of the metallicity, progenitor stars and properties such as the central density of the exploding WD are presented. IR spectroscopy, polarimetry and imaging of SNR remnants are discussed as a tool to test for the WD properties, magnetic fields and asymmetries. We discuss different classes of Type Ia supernovae, and their environment. Possible correlations between the spectroscopic and light curve properties of SN Ia are discussed. Finally, the overall emerging picture and future developments are discussed.

关键词： supernovae: general progenitors light curves spectra

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Limb preservation with suprafascial and thin perforator flaps: salvaging osteomyelitis, Charcot collapse and critical limb ischemia

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Plastic and Aesthetic Research 2019年第8期6卷 13-23页

作者： Shawn diamond Andres F.Doval Benjamin Scott Matthew L.Iorio Division of Plastic and Reconstructive Surgery Beth Israel Deaconess Medical CenterHarvard Medical SchoolBostonMA 02215USA Division of Plastic and Reconstructive Surgery University of Colorado Anschutz Medical CenterAuroraCO 80045USA.

AIM: There are limited reports in the United States demonstrating outcomes of primarily thinned fasciocutaneous flaps in the setting of critical limb ischemia, Charcot collapse and osteomyelitis. We hope to determine patient and flap related outcomes in advanced lower extremity disease. Methods: The authors conducted a retrospective review of fasciocutaneous free flaps of variable thickness for lower extremity salvage. Osteomyelitis and non-osteomyelitis patients were compared according to our primary outcome measures: functional ambulation, bone healing and complications to flap and patient. Subgroups with critical limb ischemia, Charcot collapse and diabetic foot were analyzed separately. Results: Fifty-nine patients underwent free flap reconstruction: osteomyelitis (n = 20, 34%), Charcot collapse (n = 22, 37%), and/or critical limb ischemia (n = 12, 20%). All patients underwent anterolateral thigh flaps tailored for defect-specific thicknesses: 17 superthin, 25 suprafascial, 17 subfascial. There were no significant differences between groups in terms of partial and complete flap loss (P = 1.000 and P = 0.108). Ninety-one percent of patients were ambulatory at follow up. Eighty-tive percent of individuals with osteomyelitis cleared their infection demonstrating radiographic bone healing. Two patients developed recalcitrant deep space infections ultimately requiring amputation. Subgroup analysis did not show any differences in flap related complications within the diabetic Charcot population. In multivariate regression, preoperative revascularization was independently associated with failure of limb salvage. ;Conclusion: Primarily thinned perforator flaps performed well in the setting of lower extremity limb salvage, critical limbischemia, osteomyelitis, and the Charcot foot - expanding their role in the armamentarium for lower extremity care.

关键词： Perforator flap diabetic foot limb salvage

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Is the hardness of material harder than diamond reliable?

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Journal of Materials Science & Technology 2023年第13期144卷 111-117页

作者： Jin Liu Yongtao Zou Guodong david Zhan Pei Wang Xiaozhi Yan Duanwei He Liping Wang Institute of Atomic and Molecular Physics Sichuan UniversityChengdu 610065China School of Mechanical Engineering Jingchu University of TechnologyJingmen 448000China Academy for Advanced Interdisciplinary Studies and Department of PhysicsSouthern University of Science and TechnologyShenzhen 518055China Shenzhen Key Laboratory of Ultraintense Laser&Advanced Material Technology College of Engineering Physicsand Center for Advanced Material Diagnostic TechnologyShenzhen Technology UniversityShenzhen 518118China Drilling Technology Division Exploration and Petroleum Engineering Center-Advanced Research Center(EXPEC ARC)Saudi AramcoDhahran 31311Saudi Arabia

With the development of new synthesis methods and chemistries,a number of new superhard materials have been reported to be harder than *** such materials are highly desirable due to their wide-ranging applications,there are some inherent uncertainties in the methods utilized to determine and define the hardness of such *** this paper,we employed the standard Vickers diamond indenter and substitute indenters with the same shape to measure the hardness of nine ceramics and superhard materials within well-defined criteria and methodology,for the assessment of consistency in the hardness *** findings and the developed testing method in the current study have broad implications in characterizing new and emerging superhard materials,leading to new discoveries.

关键词： Vickers hardness Superhard materials Emerging materials Applicability

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Structural and electronic properties of single-walled carbon nanotubes adsorbed with 1-pyrenebutanoic acid,succinimidyl ester

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Science China Chemistry 2008年第12期51卷 1203-1210页

作者： FAN WenJie & ZHANG RuiQin Centre of Super-diamond and Advanced Films (COSDAF) and Department of Physics and Materials Science, City University of Hong Kong, Hong Kong SAR, China Centre of Super-diamond and Advanced Films (COSDAF) and Department of Physics and Materials Science City University of Hong Kong Hong Kong SAR China

The adsorption of a 1-pyrenebutanoic acid, succinimidyl ester (PSE) interacting with metallic armchair (n, n) carbon nanotubes (CNTs) (n= 3-13) was investigated by using a density-functional tight-binding method with an empirical van der Waals force correction. In this study of large systems involving weak interactions, our calculations showed that the pyrene ring of PSE could be spontaneously absorbed onto the CNTs surface through π-π stacking at the physisorption distances. Increasing of the CNTs diameter leads to a higher adsorption energy. After adsorption of PSE on its sidewall, the geometric and electronic structures of CNTs are basically undamaged. CNTs contribute to the main peak of the electron excitation procedure in the UV/vis spectrum, with a slight red shift after adsorption of PSE.

关键词： SWNTs PSE π-π stacking density-functional tight-binding method

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diamond＋Schmitt Architects戴蒙＆史密特建筑师事务所

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建筑技术及设计 2008年第2期 24-31页

作者： diamond + Schmitt Architects Steven Evans(摄)

戴蒙＆史密特建筑师事务所（diamond＋Schmitt Architects）成立于1975年，目前包括14位主创建筑师，68名设计人员。该建筑师事务所榜列英国皇家建筑师协会（RIBA）200家世界项级建筑师事务所之中，并凭借他们对每个项目所处的环境的理... 详细信息

戴蒙＆史密特建筑师事务所（diamond＋Schmitt Architects）成立于1975年，目前包括14位主创建筑师，68名设计人员。该建筑师事务所榜列英国皇家建筑师协会（RIBA）200家世界项级建筑师事务所之中，并凭借他们对每个项目所处的环境的理解和创新性的建筑诠释，以及优秀的设计方法，而得到客户的认可。

关键词：建筑师事务所设计人员设计方法客户

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A History of the Urban Underground Tunnel (4000 B.C.E. - 1900 C.E.)

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Journal of Transportation Technologies 2018年第1期8卷 11-43页

作者： Robert Steven diamond Brian Garret Kassel Brooklyn Historic Railway Association Columbia University New York NY USA

Generally hidden from public view, out of our daily thoughts, and literally under our feet, are myriad urban underground tunnels that make our modern megacities possible. From their ancient beginnings in antiquity, as a means of supplying fresh water and draining waste water from cities, underground tunnels evolved into a means of providing high capacity rail mass transit in our most densely populated urban centers. This paper provides a broad overview of the evolution of urban tunnels across a 6000 year time span and includes the specific engineering formulas/computations for the earliest 19th century subways/infrastructure projects based on the Roman vaulted arch tunnel.

关键词： Subway Subterranean Passageway Ancient Underground Mesopotamia Greece Rome Cut and Cover Cloaca Maxima Cryptoporticus Croton Aq-ueduct Arch Tunnel Atlantic Avenue Tunnel London Railway London Tube Beach/Greathead Shield 19th Century Arched Tunnel Calculations

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A REGULARIZATION OF THE POINTWISE SUMMATION OF SINGULAR STURM-LIOUVILLE EXPANSIONS

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Analysis in Theory and Applications 1985年第5期 61-69页

作者： Harvey diamond Mark Kon Louise Raphael Department of Mathematics West Virginia University Morgantown WV Department of Mathematics Boston University Boston MA Department of Mathematics Howard University Washington DC

Suppose that the information which we are given about anL2[0,∞)function comes from a“harmonic analyzer”,which givesonly the coefficients of the expansion of f in eigenfunctions ofa Sturm-Liouville problem on[0,∞).It is well known that suchan expansion may not sum to the value of f,even at its *** us further suppose that the analyzer is imperfect,sothat the coefficients it gives deviate somewhat from the correctones.

关键词： show A REGULARIZATION OF THE POINTWISE SUMMATION OF SINGULAR STURM-LIOUVILLE EXPANSIONS

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视觉营销

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作者： (美)Stephanie diamond

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Exotic parrots breeding in urban tree cavities: nesting requirements, geographic distribution, and potential impacts on cavity nesting birds in southeast Florida

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Avian Research 2019年第4期10卷 459-468页

作者： Joshua M.diamond Michael S.Ross Florida International University Earth & Environment

Background:Exotic parrots have established breeding populations in southeast Florida,including several species that nest in tree *** aimed to determine the species identity,nest site requirements,relative nest abundance,geographic distribution,and interactions of parrots with native cavity-nesting bird ***:We searched Miami-Dade County,Florida,and nearby areas for natural cavities and holes excavated by woodpeckers,recording attributes of potential nest *** inspected all cavities with an elevated video inspection system to determine occupancy by parrots or other *** mapped nearly 4000 citizen science observations of parrots in our study area corresponding to our study period,and used these to construct range maps,comparing them to our nesting ***:Not all parrots reported or observed in our study area were actively *** parrots were observed at tree cavities,which previous studies have suggested is evidence of reproduction,but our inspections with an elevated video inspection system suggest they never initiated nesting *** parrot species did successfully nest in tree cavities,Red-masked Parakeets(Psittacara erythrogenys)and Orange-winged Parrots(Amazona amazonica)being the most common(n=7 and 6 nests,respectively).These two parrots had similar nesting requirements,but Orange-winged Parrots use nests with larger entrance holes,which they often *** analysis of nests combined with citizen science data indicate that parrots are limited to developed *** most common parrots were less abundant cavity nesters than the native birds which persist in Miami’s urban areas,and far less abundant than the invasive European Starling(Sturnus vulgaris).Conclusions:Exotic parrots breeding elsewhere in the world have harmed native cavity-nesting birds through interference competition,but competitive interference in southeast Florida is minimized by the urban affinities of parrots in this ***

关键词： Amazona Cavity nest webs Invasive species Parakeets Psittacara Urban ecology

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