FOREWORD: Peter Clay Eklund: a scientific biography Peter Clay Eklund: a scientific biography

Science.gov (United States)

Cole, Milton W.; Crespi, Vincent H.; Dresselhaus, Gene F.; Dresselhaus, Mildred S.; Mahan, Gerald D.; Sofo, Jorge O.

2010-08-01

Peter Eklund grew up in Southern California and attended the University of California at Berkeley, majoring in physics. After working for one year at the Lockheed Missile and Space Company in Sunnyvale, California, he left to pursue graduate studies at Purdue University. There he carried out PhD research in strongly correlated electron and phonon systems under the supervision of J M Honig and L L van Zandt. Peter joined the group of Millie and Gene Dresselhaus at MIT in 1974 as a Postdoctoral Fellow after one year as an instructor at the University of Kentucky. At MIT, he continued work on strongly correlated systems in collaboration with Professor David Adler (who had an adjoining office), but for the most part he got excited about sp2 carbon systems and graphite intercalation compounds, a new research direction which the Dresselhaus group had started one year before Peter's arrival at MIT. Over the next 35 years Peter, Millie and Gene co-authored over 50 research articles, several review articles, and a big nine-hundred-and-fifty page book. In 1974, they saw graphite intercalation compounds as a long-neglected research direction of great promise. They studied these new materials together over the next 16 years, focusing on their optical spectroscopy. Their pioneering vibrational spectroscopy studies provided a means to characterize the fundamental properties of carbon materials. Optical spectroscopy became a centerpiece in the research portfolios of all three, both when they were together at MIT and after Peter left for the University of Kentucky in 1977 to start his independent career as an Assistant Professor of Physics. Peter became a full Professor at Kentucky in 1986. He continued to work with Millie and Gene and also acquired an ever-expanding network of students, postdocs and collaborators. As each new carbon nanostructure emerged—graphite intercalation compounds, fullerenes, carbon nanotubes, and most recently graphene—Peter was at the cutting edge

Peter Nansen og Aalborg

DEFF Research Database (Denmark)

Bang, Karin

2005-01-01

Om Peter nansens tilknytning til Limfjordsegnen. Peter Nansen betragtede hele livet Aalborg som sin "hjemby" - det var her, han havde sin rod. Han kom til Aalborg som et-årig i april 1862, da hans far F.P.N. Nansen blev kapellan ved Budolfi Kirke. Mange af barndomsferierne tilbragte han hos sin...

R. S. Peters and the Periphery

Science.gov (United States)

Haynes, Bruce

2013-01-01

Paul Hirst claimed that Richard Peters "revolutionised philosophy of education". This does not accord with my experience in the Antipodean periphery. My experience of the work of Wittgenstein, Austin and Kovesi before reading Peters and Dewey, Kuhn and Toulmin subsequently meant that Peters was a major but not revolutionary figure in my…

Peter Petersen & Co. A/S

DEFF Research Database (Denmark)

Nygaard, Erik

1986-01-01

Peter Petersen & Co. A/S : administrations- og lagerbygning kommenteret af: Erik Nygaard. Resumé på engelsk & tysk.......Peter Petersen & Co. A/S : administrations- og lagerbygning kommenteret af: Erik Nygaard. Resumé på engelsk & tysk....

Peter Pan-demien

DEFF Research Database (Denmark)

Holm, Claus

2009-01-01

Ungdommelig opførsel er moderne. I gamle dage skulle vi blive voksne. I dag skal selv gamle mænd og kvinder holde sig unge. Peter Pan-panikken er i os, og en af vores væsentligste sociale lidelser er umodenhed.......Ungdommelig opførsel er moderne. I gamle dage skulle vi blive voksne. I dag skal selv gamle mænd og kvinder holde sig unge. Peter Pan-panikken er i os, og en af vores væsentligste sociale lidelser er umodenhed....

Peter Fisk kutsub innovatiivsusele / Kuldar Kullasepp

Index Scriptorium Estoniae

Kullasepp, Kuldar, 1980-

2007-01-01

Turunduskonverentsil Password esinenud Suurbritannia turunduskonsultandi Peter Fiski ettekandest. Lisa: Peter Fiski näited suurepärastest äridest. Aasta Turunduskonkursi korraldaja Hando Sinisalu kommentaarid konkursile: Tulemuslikkus ennekõike. Lisa: Turundustegu

Obituary: Peter Robert Wilson, 1929-2007

Science.gov (United States)

Snodgrass, Herschel B.

2009-01-01

It is with great sadness that I report the passing of Peter Robert Wilson, a well-known and well-loved figure in the solar physics community. Peter was on the faculty of the Department of Applied Mathematics at the University of Sydney for 39 years, and Chair of the department for 24 of these years. He was the author or co-author of more than 80 scientific research papers and a book, Solar and Stellar Activity Cycles (1994), published by Cambridge University Press. He died suddenly of a heart attack, at his home in Glebe, Australia, in the early morning of 11 November 2007. Peter was an organizer of, and participant in, many international conferences and workshops. He traveled extensively, holding visiting appointments at the University of Colorado (JILA), at Cambridge University, at the College de France (Paris), and at the California Institute of Technology [CalTech]. Most of his work was in the field of solar physics, but he also did some work on the philosophy of science and on tides. Peter came from a line of mathematicians. His father, Robert Wilson, immigrated to Australia from Glasgow in 1911, and became a mathematics teacher at Scotch College, a private school in Melbourne. There his name was changed to 'Bill' because 'Bob' was already taken." Peter's enjoyment of this story as characteristic of Australian academia (as any fan of Monty Python would understand) is indicative of his infectious sense of humor. In a similar vein, he claimed ancestry traced back to the eighteenth-century Scottish mathematician Alexander Wilson, Professor of Astronomy at the University of Glasgow. That Wilson is famous in the solar physics community for his discovery, known as the "Wilson Effect," of the photospheric depressions associated with sunspots. Peter himself could not resist writing a paper on this subject, and was delighted when the bait was taken by some less-informed colleagues who chided him for "naming an effect after himself." "Bill" Wilson married Naomi

The Travails of Criticality: Understanding Peter McLaren's Revolutionary Vocation. An Article Review of Peter McLaren, "Pedagogy of Insurrection" (New York: Peter Lang, 2015)

Science.gov (United States)

Baldacchino, John

2017-01-01

This is an article review of Peter McLaren's "Pedagogy of Insurrection" (New York: Peter Lang, 2015). While it seeks to position McLaren's work within the context of critical pedagogy, this paper also assesses McLaren from the wider discussion of Marxist--Hegelian discourse as it evolved within the Left. Engaging with McLaren critically,…

Theories of Power, Poverty, and Law: In Commemoration of the Contributions of Peter Bachrach--Power, Law, and Final Thoughts: The Contributions of Peter Bachrach

Science.gov (United States)

Schneider, Elizabeth M.

2010-01-01

I am pleased to be part of this symposium to celebrate the life and work of Peter Bachrach. Although my focus is the relevance of Peter's ideas of power to law, I want to begin with some personal comments as well as raise some final thoughts, drawing on others' contributions. Like so many of Peter's other students, I adored him. Peter's joy in…

Peter Priisalm eelistab juhina meeskonnamängu / Peter Priisalm ; interv. Aive Antsov

Index Scriptorium Estoniae

Priisalm, Peter

2006-01-01

AS-i Microlink Eesti juhatuse esimehe kohalt lahkunud Peter Priisalm oma tegevusest infotehnoloogiaettevõttes, tagasiastumise põhjustest, karjäärist ja selle planeerimisest ning ettevõtte juhtimisest

Peter Fisk : hoidke servale, mitte keskele / Kaido Einama

Index Scriptorium Estoniae

Einama, Kaido, 1971-

2007-01-01

Strateegi ja turundaja, Genius Worksi tegevjuhi Peter Fiski esinemisest Tallinna Lauluväljaku uues konverentsikeskuses toimunud innovatsioonikonverentsil InnoEstonia 2007. Vt. samas: Kes on Peter Fisk?

Diamond anvil cells using boron-doped diamond electrodes covered with undoped diamond insulating layer

Science.gov (United States)

Matsumoto, Ryo; Yamashita, Aichi; Hara, Hiroshi; Irifune, Tetsuo; Adachi, Shintaro; Takeya, Hiroyuki; Takano, Yoshihiko

2018-05-01

Diamond anvil cells using boron-doped metallic diamond electrodes covered with undoped diamond insulating layers have been developed for electrical transport measurements under high pressure. These designed diamonds were grown on a bottom diamond anvil via a nanofabrication process combining microwave plasma-assisted chemical vapor deposition and electron beam lithography. The resistance measurements of a high-quality FeSe superconducting single crystal under high pressure were successfully demonstrated by just putting the sample and gasket on the bottom diamond anvil directly. The superconducting transition temperature of the FeSe single crystal was increased to up to 43 K by applying uniaxial-like pressure.

Friction and wear properties of diamonds and diamond coatings

International Nuclear Information System (INIS)

Hayward, I.P.

1991-01-01

The recent development of chemical vapor deposition techniques for diamond growth enables bearings to be designed which exploit diamond's low friction and extreme resistance to wear. However, currently produced diamond coatings differ from natural diamond surfaces in that they are polycrystalline and faceted, and often contain appreciable amounts of non-diamond material (i.e. graphitic or amorphous carbon). Roughness, in particular, influences the friction and wear properties; rough coatings severely abrade softer materials, and can even wear natural diamond sliders. Nevertheless, the best available coatings exhibit friction coefficients as low as those of natural diamond and are highly resistant to wear. This paper reviews the tribological properties of natural diamond, and compares them with those of chemical vapor deposited diamond coatings. Emphasis is placed on the roles played by roughness and material transfer in controlling frictional behavior. (orig.)

Constructing the economic–historic context of 1 Peter: Exploring a ...

African Journals Online (AJOL)

Test

2010-09-30

Sep 30, 2010 ... addressees of 1 Peter, which could serve as basis for an economic interpretation of 1 Peter and other New Testament books. After discussing 1 Peter as ...... the Empire, Harvard University Press, Cambridge. McCaughey, J.D. ...

Kalevipoeg - ein Interview mit Prof. Dr. Peter Petersen / Peter Petersen ; interv. Laine Paavo

Index Scriptorium Estoniae

Petersen, Peter

2005-01-01

Kalevipoja uuest saksakeelsest väljaandest: Kalevipoeg : das estnische Nationalepos / in der Übersetzung von Ferdinand Löwe ; herausgegeben von Peter Petersen Ilm. andmed Stuttgart ; Berlin : Mayer, 2004.

Diamond Fuzzy Number

Directory of Open Access Journals (Sweden)

T. Pathinathan

2015-01-01

Full Text Available In this paper we define diamond fuzzy number with the help of triangular fuzzy number. We include basic arithmetic operations like addition, subtraction of diamond fuzzy numbers with examples. We define diamond fuzzy matrix with some matrix properties. We have defined Nested diamond fuzzy number and Linked diamond fuzzy number. We have further classified Right Linked Diamond Fuzzy number and Left Linked Diamond Fuzzy number. Finally we have verified the arithmetic operations for the above mentioned types of Diamond Fuzzy Numbers.

Diamond Pixel Detectors and 3D Diamond Devices

International Nuclear Information System (INIS)

Venturi, N.

2016-01-01

Results from detectors of poly-crystalline chemical vapour deposited (pCVD) diamond are presented. These include the first analysis of data of the ATLAS Diamond Beam Monitor (DBM). The DBM module consists of pCVD diamond sensors instrumented with pixellated FE-I4 front-end electronics. Six diamond telescopes, each with three modules, are placed symmetrically around the ATLAS interaction point. The DBM tracking capabilities allow it to discriminate between particles coming from the interaction point and background particles passing through the ATLAS detector. Also, analysis of test beam data of pCVD DBM modules are presented. A new low threshold tuning algorithm based on noise occupancy was developed which increases the DBM module signal to noise ratio significantly. Finally first results from prototypes of a novel detector using pCVD diamond and resistive electrodes in the bulk, forming a 3D diamond device, are discussed. 3D devices based on pCVD diamond were successfully tested with test beams at CERN. The measured charge is compared to that of a strip detector mounted on the same pCVD diamond showing that the 3D device collects significantly more charge than the planar device.

Seasonal abundance of eggplant leafminer Liriomyza sativae (Blanchard, 1938) (Diptera, Agromyzidae) in plastic-house

Science.gov (United States)

Kathiar, S. A.; Flaih, S. K.; Al-Khazraji, H. I.; Ismael, S. K.

2018-05-01

The eggplant Solanum melongena L. crop is attacked by one of the most common pests which is the leafminer Liriomyza sativae (Blanchard, 1938); therefore, this investigation was conducted to study the seasonal abundance of the eggplant leafminer in eggplant Plastic-house. The results showed that the highest average of infested leaves was 6.67 leaf, the highest average of tunnels by leaf miner was 9.87 tunnels and the highest percent of infestation was recorded 30.5% in 23. April. 2017. This study showed the parasitoid Diglyphus isaea (Walker, 1838) (Hymenoptera, Eulophidae) was recorded as a natural enemy to control the pest and the highest incidence of parasitism was 32.2 parasites on average in 16. April. 2017.

Diamond bio electronics.

Science.gov (United States)

Linares, Robert; Doering, Patrick; Linares, Bryant

2009-01-01

The use of diamond for advanced applications has been the dream of mankind for centuries. Until recently this dream has been realized only in the use of diamond for gemstones and abrasive applications where tons of diamonds are used on an annual basis. Diamond is the material system of choice for many applications, but its use has historically been limited due to the small size, high cost, and inconsistent (and typically poor) quality of available diamond materials until recently. The recent development of high quality, single crystal diamond crystal growth via the Chemical Vapor Deposition (CVD) process has allowed physcists and increasingly scientists in the life science area to think beyond these limitations and envision how diamond may be used in advanced applications ranging from quantum computing, to power generation and molecular imaging, and eventually even diamond nano-bots. Because of diamond's unique properties as a bio-compatible material, better understanding of diamond's quantum effects and a convergence of mass production, semiconductor-like fabrication process, diamond now promises a unique and powerful key to the realization of the bio-electronic devices being envisioned for the new era of medical science. The combination of robust in-the-body diamond based sensors, coupled with smart bio-functionalized diamond devices may lead to diamond being the platform of choice for bio-electronics. This generation of diamond based bio-electronic devices would contribute substantially to ushering in a paradigm shift for medical science, leading to vastly improved patient diagnosis, decrease of drug development costs and risks, and improved effectiveness of drug delivery and gene therapy programs through better timed and more customized solutions.

Peter Lorange: ära murra oma sõna isegi raskel ajal! / Peter Lorange

Index Scriptorium Estoniae

Lorange, Peter, 1943-

2009-01-01

Euroopa parima ärikooli IMD endine president ning mitmete ülikoolide audoktor Peter Lorange vastab küsimustele, mis puudutavad rahvusvahelises ärikoolis õppimist, Eesti ärihariduseta juhtide õppimist ja õppimise võimalusi ning soovitusi juhtidele majanduslanguse ajaks

Ritual, Imitation and Education in R. S. Peters

Science.gov (United States)

Warnick, Bryan R.

2009-01-01

This article reconstructs R. S. Peters' underlying theory of ritual in education, highlighting his proposed link between ritual and the imitation of teachers. Rituals set the stage for the imitation of teachers and they invite students to experience practices whose value is not easily discernable from the outside. For Peters, rituals facilitate…

Lateral overgrowth of diamond film on stripes patterned Ir/HPHT-diamond substrate

Science.gov (United States)

Wang, Yan-Feng; Chang, Xiaohui; Liu, Zhangcheng; Liu, Zongchen; Fu, Jiao; Zhao, Dan; Shao, Guoqing; Wang, Juan; Zhang, Shaopeng; Liang, Yan; Zhu, Tianfei; Wang, Wei; Wang, Hong-Xing

2018-05-01

Epitaxial lateral overgrowth (ELO) of diamond films on patterned Ir/(0 0 1)HPHT-diamond substrates have been carried out by microwave plasma CVD system. Ir/(0 0 1)HPHT-diamond substrates are fabricated by photolithographic and magnetron sputtering technique. The morphology of the as grown ELO diamond film is characterized by optical microscopy and scanning electronic microscopy. The quality and stress of the ELO diamond film are investigated by surface etching pit density and micro-Raman spectroscopy. Two ultraviolet photodetectors are fabricated on ELO diamond area and non-ELO diamond area prepared on same substrate, and that one on ELO diamond area indicates better photoelectric properties. All results indicate quality of ELO diamond film is improved.

Peter Lax, mathematician an illustrated memoir

CERN Document Server

Hersh, Reuben

2015-01-01

Hersh's memoir of Peter Lax is a revealing glimpse into the life, times, and work of one of the giants of mathematics. The story, told through reminiscences and interviews with Lax himself, his family, and his close friends, is the story of mathematics and its relationships to science and society from the Second World War to the end of the century. -Charlie Epstein, University of Pennsylvania This book is a biography of one of the most famous and influential living mathematicians, Peter Lax. He is virtually unique as a preeminent leader in both pure and applied mathematics, fields which are o

Peter Schlechtriem zum Gedächtnis - in memoriam Peter Schlechtriem / Rolf Herber, Jan Ramberg

Index Scriptorium Estoniae

Herber, Rolf

2007-01-01

Järelehüüe Saksa tsiviilõiguse arendajale, mitmete Euroopa ja Ameerika Ühendriikide ülikoolide külalisõppejõule, Tartu Ülikooli audoktorile, professor Peter H. Schlechtriemile (02. 03. 1933-23. 04. 2007)

Diamond identifaction

International Nuclear Information System (INIS)

1976-01-01

X-ray topography on diamonds allows for unique identification of diamonds. The method described consists of the registration of crystal defects, inclusions etc. of a diamond, resulting in a 'finger print' of the individual jewel which can only be changed by its complete destruction

Diamond identification

International Nuclear Information System (INIS)

Lang, A.R.

1979-01-01

Methods of producing sets of records of the internal defects of diamonds as a means of identification of the gems by x-ray topography are described. To obtain the records one can either use (a) monochromatic x-radiation reflected at the Bragg angle from crystallographically equivalent planes of the diamond lattice structure, Bragg reflections from each such plane being recorded from a number of directions of view, or (b) white x-radiation incident upon the diamond in directions having a constant angular relationship to each equivalent axis of symmetry of the diamond lattice structure, Bragg reflections being recorded for each direction of the incident x-radiation. By either method an overall point-to-point three dimensional representation of the diamond is produced. (U.K.)

Jim Peters' collapse in the 1954 Vancouver Empire Games marathon.

Science.gov (United States)

Noakes, Tim; Mekler, Jackie; Pedoe, Dan Tunstall

2008-08-01

On 7 August 1954, the world 42 km marathon record holder, Jim Peters, collapsed repeatedly during the final 385 metres of the British Empire and Commonwealth Games marathon held in Vancouver, Canada. It has been assumed that Peters collapsed from heatstroke because he ran too fast and did not drink during the race, which was held in windless, cloudless conditions with a dry-bulb temperature of 28 degrees C. Hospital records made available to us indicate that Peters might not have suffered from exertional heatstroke, which classically produces a rectal temperature > 42 degrees C, cerebral effects and, usually, a fatal outcome without vigorous active cooling. Although Peters was unconscious on admission to hospital approximately 60 minutes after he was removed from the race, his rectal temperature was 39.4 degrees C and he recovered fully, even though he was managed conservatively and not actively cooled. We propose that Peters' collapse was more likely due to a combination of hyperthermia-induced fatigue which caused him to stop running; exercise-associated postural hypotension as a result of a low peripheral vascular resistance immediately he stopped running; and combined cerebral effects of hyperthermia, hypertonic hypernatraemia associated with dehydration, and perhaps undiagnosed hypoglycaemia. But none of these conditions should cause prolonged unconsciousness, raising the possibility that Peters might have suffered from a transient encephalopathy, the exact nature of which is not understood.

Diamonds on Diamond: structural studies at extreme conditions on the Diamond Light Source.

Science.gov (United States)

McMahon, M I

2015-03-06

Extreme conditions (EC) research investigates how the structures and physical and chemical properties of materials change when subjected to extremes of pressure and temperature. Pressures in excess of one million times atmospheric pressure can be achieved using a diamond anvil cell, and, in combination with high-energy, micro-focused radiation from a third-generation synchrotron such as Diamond, detailed structural information can be obtained using either powder or single-crystal diffraction techniques. Here, I summarize some of the research drivers behind international EC research, and then briefly describe the techniques by which high-quality diffraction data are obtained. I then highlight the breadth of EC research possible on Diamond by summarizing four examples from work conducted on the I15 and I19 beamlines, including a study which resulted in the first research paper from Diamond. Finally, I look to the future, and speculate as to the type of EC research might be conducted at Diamond over the next 10 years. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

Toward deep blue nano hope diamonds: heavily boron-doped diamond nanoparticles.

Science.gov (United States)

Heyer, Steffen; Janssen, Wiebke; Turner, Stuart; Lu, Ying-Gang; Yeap, Weng Siang; Verbeeck, Jo; Haenen, Ken; Krueger, Anke

2014-06-24

The production of boron-doped diamond nanoparticles enables the application of this material for a broad range of fields, such as electrochemistry, thermal management, and fundamental superconductivity research. Here we present the production of highly boron-doped diamond nanoparticles using boron-doped CVD diamond films as a starting material. In a multistep milling process followed by purification and surface oxidation we obtained diamond nanoparticles of 10-60 nm with a boron content of approximately 2.3 × 10(21) cm(-3). Aberration-corrected HRTEM reveals the presence of defects within individual diamond grains, as well as a very thin nondiamond carbon layer at the particle surface. The boron K-edge electron energy-loss near-edge fine structure demonstrates that the B atoms are tetrahedrally embedded into the diamond lattice. The boron-doped diamond nanoparticles have been used to nucleate growth of a boron-doped diamond film by CVD that does not contain an insulating seeding layer.

77 FR 26538 - Vigue, Peter A.; Notice of Filing

Science.gov (United States)

2012-05-04

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket No. ID-6627-001] Vigue, Peter A.; Notice of Filing Take notice that on April 26, 2012, Peter A. Vigue submitted for filing, a supplement to the application for authority to hold interlocking positions filed on March 6, 2012, pursuant to...

Nobel euro isale / Peter Lõhmus

Index Scriptorium Estoniae

Lõhmus, Peter

1999-01-01

Eesti Panga asepresident Peter Lõhmus tutvustab oma õpetajat, New Yorgi Columbia Ülikooli professorit Robert Mundelli, kes sai tänavase Nobeli majanduspreemia. Eeskätt on Mundell tuntud kui nn. optimaalse valuutapiirkonna teooria rajaja

Anterior segment dysgenesis (Peters' anomaly) in two snow leopard (Panthera uncia) cubs

DEFF Research Database (Denmark)

Hamoudi, Hassan; Rudnick, Jens-Christian; Prause, Jan Ulrik

2013-01-01

remnant of the hyaloid artery. The male had hydrocephalus and thus some of the features of Peters' plus syndrome (Peters' anomaly in addition to systemic malformations). The histological findings in the eyes of these snow leopard siblings are identical with those described in humans with Peters' anomaly....

77 FR 14773 - Vigue, Peter A.; Notice of Filing

Science.gov (United States)

2012-03-13

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket No. ID-6627-001] Vigue, Peter A.; Notice of Filing Take notice that on March 6, 2012, Peter A. Vigue submitted for filing, an application for authority to hold interlocking positions, pursuant to section 305(b) of the Federal Power Act, 16...

Peter H. Schlechtriem / Ingeborg Schwenzer

Index Scriptorium Estoniae

Schwenzer, Ingeborg

2007-01-01

Järelehüüe Saksa tsiviilõiguse arendajale, mitmete Euroopa ja Ameerika Ühendriikide ülikoolide külalisõppejõule, Tartu Ülikooli audoktorile, professor Peter H. Schlechtriemile (02. 03. 1933-23. 04. 2007)

Detection of diamonds

International Nuclear Information System (INIS)

Hansen, J.O.; Blondeel, E.J.G.; Taylor, G.T.

1991-01-01

Diamond particles are distinguished from non-diamond, associated particles on the basis of their higher refractive index. The particles are brought to a specific location, typically in a stream of water flowing full in a vertical duct, and a beam of collimated electromagnetic radiation is directed at them. An array of radiation detectors is provided to detect refracted and/or reflected radiation. The array is so configured that the responses of the detectors, considered collectively, will be indicative of the presence of a diamond when a diamond is in fact present. However, when a particle having a substantially lower refractive index is present, the responses of the detectors will not be so indicative. The diamond and non-diamond particles can subsequently be sorted from one another

Peter Crockaert on Self-Reference

Czech Academy of Sciences Publication Activity Database

Hanke, Miroslav

-, č. 28/52 (2014), s. 145-167 ISSN 0231-5955 R&D Projects: GA ČR(CZ) GP13-08389P Institutional support: RVO:67985955 Keywords : Peter Crockaert * Semantic paradoxes * Scholastic logic * Thomism Subject RIV: AA - Philosophy ; Religion

75 FR 49992 - Peter W.S. Grigg, M.D.; Revocation of Registration

Science.gov (United States)

2010-08-16

... DEPARTMENT OF JUSTICE Drug Enforcement Administration Peter W.S. Grigg, M.D.; Revocation of... Order to Show Cause and Immediate Suspension of Registration to Peter W.S. Grigg, M.D. (Respondent), of... Registration, BG2107856, issued to Peter W.S. Grigg, M.D., be, and it hereby is, revoked. This Order is...

Peter A. Florschutz

Directory of Open Access Journals (Sweden)

Cleef Antoine M.

1978-12-01

Full Text Available El 25 de mayo de 1976 falleció inesperadamente, a la edad de53 años, Peter Arnold Florschütz, eminente briólogo y profesor deBotánica Sistemática en Utrecht (Holanda. Era bien conocido porsus estudios de los musgos de Surinam. Fue coautor del "Index Muscorum", miembro de la comisión de la Flora Neotrópica y tesorero del IAPT.

Synthetic diamond in electrochemistry

International Nuclear Information System (INIS)

Pleskov, Yurii V

1999-01-01

The results of studies on the electrochemistry of diamond carried out during the last decade are reviewed. Methods for the preparation, the crystalline structure and the main electrophysical properties of diamond thin films are considered. Depending on the doping conditions, the diamond behaves as a superwide-gap semiconductor or as a semimetal. It is shown that the 'metal-like' diamond is corrosion-resistant and can be used advantageously as an electrode in the electrosynthesis (in particular, for the electroreduction of compounds that are difficult to reduce) and electroanalysis. Kinetic characteristics of some redox reactions and the impedance parameters for diamond electrodes are presented. The results of comparative studies of the electrodes made of diamond single crystals, polycrystalline diamond and amorphous diamond-like carbon, which reveal the effect of the crystalline structure (e.g., the influence of intercrystallite boundaries) on the electrochemical properties of diamond, are presented. The bibliography includes 99 references.

Structure and properties of diamond and diamond-like films

Energy Technology Data Exchange (ETDEWEB)

Clausing, R.E. [Oak Ridge National Lab., TN (United States)

1993-01-01

This section is broken into four parts: (1) introduction, (2) natural IIa diamond, (3) importance of structure and composition, and (4) control of structure and properties. Conclusions of this discussion are that properties of chemical vapor deposited diamond films can compare favorably with natural diamond, that properties are anisotropic and are a strong function of structure and crystal perfection, that crystal perfection and morphology are functions of growth conditions and can be controlled, and that the manipulation of texture and thereby surface morphology and internal crystal perfection is an important step in optimizing chemically deposited diamond films for applications.

Peter Waterman and his scientific legacy

Science.gov (United States)

Mishchenko, Michael I.; Kahnert, Michael; Mackowski, Daniel W.; Wriedt, Thomas

2013-01-01

Peter C. Waterman, a giant figure in the theory of electromagnetic, acoustic, and elastic wave scattering, passed away on 3 June, 2012. In view of his fundamental contributions, which to a large degree have guided the progress of these disciplines over the past five decades and affected profoundly the multifaceted research published in the Journal of Quantitative Spectroscopy and Radiative Transfer (JQSRT), we felt that it would be appropriate to solicit papers for a special issue of JQSRT commemorating Peter Waterman's scientific legacy. This initiative was endorsed by the JQSRT management and has resulted in a representative collection of high-quality papers which have undergone the same peer scrutiny as any paper submitted to JQSRT.

Diamond semiconducting devices

International Nuclear Information System (INIS)

Polowczyk, M.; Klugmann, E.

1999-01-01

Many efforts to apply the semiconducting diamond for construction of electronic elements: resistors, thermistors, photoresistors, piezoresistors, hallotrons, pn diodes, Schottky diodes, IMPATT diodes, npn transistor, MESFETs and MISFETs are reviewed. Considering the possibilities of acceptor and donor doping, electrical resistivity and thermal conductivity of diamond as well as high electric-field breakdown points, that diamond devices could be used at about 30-times higher frequency and more then 8200 times power than silicon devices. Except that, due to high heat resistant of diamond, it is concluded that diamond devices can be used in environment at high temperature, range of 600 o C. (author)

Estádios evolutivos de tripanossomas de Hipostomus punctatus Valenciennes (Osteichthyes, Loricariidae em infecção natural de Batracobdella gemmata Blanchard (Hirudinea, Glossiphoniidae Evolutive stages of tripanosomes of Hipostomus punctatus Valenciennes (Osteichthyes, Loricariidae in natural infection of Batracobdella gemmata Blanchard (Hirudinea, Glossiphoniidae

Directory of Open Access Journals (Sweden)

Marta D'Agosto

1993-01-01

Full Text Available Seventeen leeches obtained from armoured catfish (Hypostomus punclatus Valenciennes, 1840 infected with Trypanosoma spp. were examined. It was observed the presence of tripomastigotes, epimastigotes and amastigotes forms as well as dividing forms in the proboscis and in the stomach, different from the ones found in the vertebrate host as regards the morfometric features and developing forms. The examination of the contents of rectum did not show tripanosomes. These facts seem to demonstrate that Batracobdella gemmata (Blanchard, 1900 is an invertebrate host of trypanosomes and the transmission is done by means of inoculation.

Noble gas studies in vapor-growth diamonds: Comparison with shock-produced diamonds and the origin of diamonds in ureilites

Energy Technology Data Exchange (ETDEWEB)

Matsuda, Junichi; Fukunaga, Kazuya; Ito, Keisuke (Kobe Univ. (Japan))

1991-07-01

The authors synthesized vapor-trowth diamonds by two kinds of Chemical Vapor Deposition (CVD) using microwave (MWCVD) and hot filament (HFCVD) ionization of gases, and examined elemental abundances and isotopic compositions of the noble gases trapped in the diamonds. It is remarkable that strong differences existed in the noble gas concentrations in the two kinds of CVD diamonds: large amounts of noble gases were trapped in the MWCVD diamonds, but not in the HFCVD diamonds. The heavy noble gases (Ar to Xe) in the MWCVD diamonds were highly fractionated compared with those in the ambient atmosphere, and are in good agreement with the calculated fractionation patterns for plasma at an electron temperature of 7,000-9,000 K. These results strongly suggest that the trapping mechanism of noble gases in CVD diamonds is ion implantation during diamond growth. The degrees of fractionation of heavy noble gases were also in good agreement with those in ureilites. The vapor-growth hypothesis is discussed in comparison with the impact-shock hypothesis as a better model for the origin of diamonds in ureilites. The diamond (and graphite, amorphous carbon, too) may have been deposited on early condensates such as Re, Ir, W, etc. This model explains the chemical features of vein material in ureilites; the refractory siderophile elements are enriched in carbon and noble gases and low in normal siderophiles. The vapor-growth model is also compatible with the oxygen isotopic data of ureilites which suggests that nebular processes are primarily responsible for the composition of ureilites.

Anomalia de Peters, seus aspectos clínicos e terapêuticos: relato de caso Peter's anomaly, clinical and therapeutic aspects: case report

Directory of Open Access Journals (Sweden)

Isadora Meyer

2010-08-01

Full Text Available A anomalia de Peters consiste na mais comum opacidade corneana congênita e é secundária à malformação do segmento anterior do olho. Suas principais características são opacidade corneana central e sinéquias da íris e/ou do cristalino com a região do leucoma. Pode apresentar-se de forma isolada ou associada a outras anomalias oculares e sistêmicas, tendo prognóstico mais sombrio nestes casos. A etiologia da anomalia Peters permanece incerta, sendo aventadas causas genéticas, infecciosas, traumáticas e tóxicas. O tratamento varia com a apresentação do quadro, sendo importante a pronta detecção da doença, possibilitando o tratamento precoce, com bom desenvolvimento da visão. Este trabalho relata um caso de anomalia de Peters diagnosticado tardiamente e discute as características da doença e possibilidades de tratamento.Peter's anomaly consists in the most common congenital corneal opacity related to a malformation of the anterior segment of the eye. Its main characteristics are central leukoma and iridocorneal adherences at the area affected by the leukoma. It can be identified isolated or in association with other ocular or systemic abnormalities, and the prognostic tend to be worse in the latter cases. The etiology of Peter's anomaly remains uncertain, but the most likely causes are related to genetic, infectious, traumatic and toxic factors. A range of possible treatment strategies exists, though the effectiveness of each of them depends on how the disease occurs and whether it is identified in early or advanced stages - the earlier the diagnosis, the higher the possibility of a successful intervention, given that precocious treatments are more likely to result in a good development of the vision. This work reports a case of Peter's anomaly that was diagnosed in an advanced stage, discussing the characteristics of the case and treatment possibilities.

What Would Peter Drucker Say?

Science.gov (United States)

Sundre, Steven M.; Raisch, C. Daniel

2002-01-01

Applies observations and advice by management guru Peter F. Drucker to the role of school system leaders. Topics include the customer as king, the continually changing definition of success, effective time management, the ethical dimension of decision making, and performance-based leadership (MLF)

Peter Mandelson: laienemisel on nii poliitiline kui ka majanduslik tähendus / Peter Mandelson ; interv. Marianne Mikko

Index Scriptorium Estoniae

Mandelson, Peter

2004-01-01

Tuntud Briti poliitik Peter Mandelson on üks kindlamaid kandidaate Euroopa Komisjoni voliniku kohale. Euroopa Komisjonist, Euroopa Liidu roteeruvast juhtimisest, eurost, migratsioonist, terrorismist, suhetest USA-ga, Iraagi tulevikust

Diamond Synthesis Employing Nanoparticle Seeds

Science.gov (United States)

Uppireddi, Kishore (Inventor); Morell, Gerardo (Inventor); Weiner, Brad R. (Inventor)

2014-01-01

Iron nanoparticles were employed to induce the synthesis of diamond on molybdenum, silicon, and quartz substrates. Diamond films were grown using conventional conditions for diamond synthesis by hot filament chemical vapor deposition, except that dispersed iron oxide nanoparticles replaced the seeding. This approach to diamond induction can be combined with dip pen nanolithography for the selective deposition of diamond and diamond patterning while avoiding surface damage associated to diamond-seeding methods.

Recognition of diamond grains on surface of fine diamond grinding wheel

Institute of Scientific and Technical Information of China (English)

Fengwei HUO; Zhuji JIN; Renke KANG; Dongming GUO; Chun YANG

2008-01-01

The accurate evaluation of grinding wheel sur-face topography, which is necessary for the investigation of the grinding principle, optimism, modeling, and simu-lation of a grinding process, significantly depends on the accurate recognition of abrasive grains from the measured wheel surface. A detailed analysis of the grain size distri-bution characteristics and grain profile wavelength of the fine diamond grinding wheel used for ultra-precision grinding is presented. The requirements of the spatial sampling interval and sampling area for instruments to measure the surface topography of a diamond grinding wheel are discussed. To recognize diamond grains, digital filtering is used to eliminate the high frequency disturb-ance from the measured 3D digital surface of the grinding wheel, the geometric features of diamond grains are then extracted from the filtered 3D digital surface, and a method based on the grain profile frequency characteris-tics, diamond grain curvature, and distance between two adjacent diamond grains is proposed. A 3D surface pro-filer based on scanning white light interferometry is used to measure the 3D surface topography of a #3000 mesh resin bonded diamond grinding wheel, and the diamond grains are then recognized from the 3D digital surface. The experimental result shows that the proposed method is reasonable and effective.

Anisotropic diamond etching through thermochemical reaction between Ni and diamond in high-temperature water vapour.

Science.gov (United States)

Nagai, Masatsugu; Nakanishi, Kazuhiro; Takahashi, Hiraku; Kato, Hiromitsu; Makino, Toshiharu; Yamasaki, Satoshi; Matsumoto, Tsubasa; Inokuma, Takao; Tokuda, Norio

2018-04-27

Diamond possesses excellent physical and electronic properties, and thus various applications that use diamond are under development. Additionally, the control of diamond geometry by etching technique is essential for such applications. However, conventional wet processes used for etching other materials are ineffective for diamond. Moreover, plasma processes currently employed for diamond etching are not selective, and plasma-induced damage to diamond deteriorates the device-performances. Here, we report a non-plasma etching process for single crystal diamond using thermochemical reaction between Ni and diamond in high-temperature water vapour. Diamond under Ni films was selectively etched, with no etching at other locations. A diamond-etching rate of approximately 8.7 μm/min (1000 °C) was successfully achieved. To the best of our knowledge, this rate is considerably greater than those reported so far for other diamond-etching processes, including plasma processes. The anisotropy observed for this diamond etching was considerably similar to that observed for Si etching using KOH.

Diamond and Diamond-Like Materials as Hydrogen Isotope Barriers

International Nuclear Information System (INIS)

Foreman, L.R.; Barbero, R.S.; Carroll, D.W.; Archuleta, T.; Baker, J.; Devlin, D.; Duke, J.; Loemier, D.; Trukla, M.

1999-01-01

This is the final report of a two-year, Laboratory Directed Research and Development (LDRD) project at Los Alamos National Laboratory (LANL). The purpose of this project was to develop diamond and diamond-like thin-films as hydrogen isotope permeation barriers. Hydrogen embrittlement limits the life of boost systems which otherwise might be increased to 25 years with a successful non-reactive barrier. Applications in tritium processing such as bottle filling processes, tritium recovery processes, and target filling processes could benefit from an effective barrier. Diamond-like films used for low permeability shells for ICF and HEDP targets were also investigated. Unacceptable high permeabilities for hydrogen were obtained for plasma-CVD diamond-like-carbon films

Comparison between beryllium and diamond-backing plates in diamond-anvil cells

DEFF Research Database (Denmark)

Periotto, Benedetta; Nestola, Fabrizio; Balic Zunic, Tonci

2011-01-01

A direct comparison between two complete intensity datasets, collected on the same sample loaded in two identical diamond-anvil pressure cells equipped, respectively, with beryllium and diamond backing plates was performed. The results clearly demonstrate that the use of diamond-backing plates...

Plasma spraying method for forming diamond and diamond-like coatings

Science.gov (United States)

Holcombe, Cressie E.; Seals, Roland D.; Price, R. Eugene

1997-01-01

A method and composition for the deposition of a thick layer (10) of diamond or diamond-like material. The method includes high temperature processing wherein a selected composition (12) including at least glassy carbon is heated in a direct current plasma arc device to a selected temperature above the softening point, in an inert atmosphere, and is propelled to quickly quenched on a selected substrate (20). The softened or molten composition (18) crystallizes on the substrate (20) to form a thick deposition layer (10) comprising at least a diamond or diamond-like material. The selected composition (12) includes at least glassy carbon as a primary constituent (14) and may include at least one secondary constituent (16). Preferably, the secondary constituents (16) are selected from the group consisting of at least diamond powder, boron carbide (B.sub.4 C) powder and mixtures thereof.

Entrevista a Peter Wade

Directory of Open Access Journals (Sweden)

Herminia Gonzálvez Torralbo

2007-09-01

Full Text Available Peter Wade, Doctor en Antropología Social por la Universidad de Cambridge y actualmente profesor en la Universidad de Manchester (Reino Unido ha dedicado la mayor parte de su vida a explorar las relaciones étnicas y las ideas de raza que existen en América Latina, con particular referencia a las poblaciones negras. A lo largo de su trayectoria académica Peter Wade ha estudiado los procesos de discriminación racial, identidad negra, y movimiento social negro, incorporando también la sexualidad a sus temas centrales de investigación. Wade es autor de libros como “Raza y Etnicidad en América Latina” o “Música, Raza y Nación”, una de las mejores publicaciones sobre música popular colombiana, y de artículos como Afro-Latin Studies: Reflections on the Field o Hybridity Theory and Kinship Thinking. En la actualidad combina su labor docente con su participación en el macro proyecto Public Undestanding of Genetics (PUG, que cuenta con siete equipos de investigación en diferentes países de la Unión Europea.

Peter Severin Fønss

DEFF Research Database (Denmark)

Jensen, Mette Frisk

2016-01-01

I begyndelsen af 1800-tallet var Danmark præget af krigstilstanden under Englandskrigene i 1801 og 1807-1814, statsbankerotten i januar 1813 og en voldsom økonomisk krise, der satte ind under krigen og fortsatte frem til slutningen af 1820’erne. Fra 1818 blev landets vigtigste erhverv, landbruget...... korruption. Amtmanden i Randers Amt fra 1805 til 1820, Peter Severin Fønss, var en af dem....

Peter McLaren & the 3 R’s: Reflection, Resistance and Revolution

Directory of Open Access Journals (Sweden)

David Gabbard

2006-10-01

Full Text Available I cannot feign some distanced objectivity in writing this profile of Peter McLaren. Our relationship dates back to 1989, when Philip Stedman, one of my professors at the University of Cincinnati, invited me to accompany him on a visit to Peter at nearby Miami University of Ohio. I had read some of Peter’s work, particularly some of his early collaborations with Henry Giroux, who had helped bring Peter to Miami from Canada. No amount of reading, however, could have prepared me for meeting him face-to-face.

Diamond film growth with modification properties of adhesion between substrate and diamond film

Directory of Open Access Journals (Sweden)

Setasuwon P.

2004-03-01

Full Text Available Diamond film growth was studied using chemical vapor deposition (CVD. A special equipment was build in-house, employing a welding torch, and substrate holder with a water-cooling system. Acetylene and oxygen were used as combustion gases and the substrate was tungsten carbide cobalt. It was found that surface treatments, such as diamond powder scratching or acid etching, increase the adhesion and prevent the film peel-off. Diamond powder scratching and combined diamond powder scratching with acid etching gave the similar diamond film structure with small grain and slightly rough surface. The diamond film obtained with both treatments has high adhesion and can withstand internal stress better than ones obtained by untreated surface or acid etching alone. It was also found that higher substrate temperature produced smoother surface and more uniform diamond grain.

R. S. Peters' Normative Conception of Education and Educational Aims

Science.gov (United States)

Katz, Michael S.

2009-01-01

This article aims to highlight why R. S. Peters' conceptual analysis of "education" was such an important contribution to the normative field of philosophy of education. In the article, I do the following: 1) explicate Peters' conception of philosophy of education as a field of philosophy and explain his approach to the philosophical analysis of…

Self-composite comprised of nanocrystalline diamond and a non-diamond component useful for thermoelectric applications

Science.gov (United States)

Gruen, Dieter M [Downers Grove, IL

2009-08-11

One provides nanocrystalline diamond material that comprises a plurality of substantially ordered diamond crystallites that are sized no larger than about 10 nanometers. One then disposes a non-diamond component within the nanocrystalline diamond material. By one approach this non-diamond component comprises an electrical conductor that is formed at the grain boundaries that separate the diamond crystallites from one another. The resultant nanowire is then able to exhibit a desired increase with respect to its ability to conduct electricity while also preserving the thermal conductivity behavior of the nanocrystalline diamond material.

Diamonds for beam instrumentation

International Nuclear Information System (INIS)

Griesmayer, Erich

2013-01-01

Diamond is perhaps the most versatile, efficient and radiation tolerant material available for use in beam detectors with a correspondingly wide range of applications in beam instrumentation. Numerous practical applications have demonstrated and exploited the sensitivity of diamond to charged particles, photons and neutrons. In this paper, a brief description of a generic diamond detector is given and the interaction of the CVD diamond detector material with protons, electrons, photons and neutrons is presented. Latest results of the interaction of sCVD diamond with 14 MeV mono-energetic neutrons are shown.

Ciclo de vida, hábitos y enemigos naturales de Liriomyza sativae blanchard (Diptera: agromyzidae), minador del fríjol

OpenAIRE

Cruz L. Jaime de la; Cruz R. Ana M. de la; Cardona J. César

1989-01-01

El presente estudio se realizó en el Centro Internacional de Agricultura Tropical CIAT, Palmira. Se consideró como objetivo principal el estudio biológico del minador del fríjol liriomyza sativae Blanchard, en condiciones controladas de invernadero y sus enemigos naturales. Se hizo la descripción morfológica de todos los estados de desarrollo del insecto y de los daños ocasionados por el adulto. Igualmente se midió la duración del ciclo de vida en condiciones controladas; temperatura promedia...

Kankan diamonds (Guinea) III: δ13C and nitrogen characteristics of deep diamonds

Science.gov (United States)

Stachel, T.; Harris, J. W.; Aulbach, S.; Deines, P.

Diamonds from the Kankan area in Guinea formed over a large depth profile beginning within the cratonic mantle lithosphere and extending through the asthenosphere and transition zone into the lower mantle. The carbon isotopic composition, the concentration of nitrogen impurities and the nitrogen aggregation level of diamonds representing this entire depth range have been determined. Peridotitic and eclogitic diamonds of lithospheric origin from Kankan have carbon isotopic compositions (δ13C: peridotitic -5.4 to -2.2‰ eclogitic -19.7 to -0.7‰) and nitrogen characteristics (N: peridotitic 17-648 atomic ppm; eclogitic 0-1,313 atomic ppm; aggregation from IaA to IaB) which are generally typical for diamonds of these two suites worldwide. Geothermobarometry of peridotitic and eclogitic inclusion parageneses (worldwide sources) indicates that both suites formed under very similar conditions within the cratonic lithosphere, which is not consistent with a derivation of diamonds with light carbon isotopic composition from subducted organic matter within subducting oceanic slabs. Diamonds containing majorite garnet inclusions fall to the isotopically heavy side (δ13C: -3.1‰ to +0.9‰) of the worldwide diamond population. Nitrogen contents are low (0-126 atomic ppm) and one of the two nitrogen-bearing diamonds shows such a low level of nitrogen aggregation (30% B-centre) that it cannot have been exposed to ambient temperatures of the transition zone (>=1,400 °C) for more than 0.2 Ma. This suggests rapid upward transport and formation of some Kankan diamonds pene-contemporaneous to Cretaceous kimberlite activity. Similar to these diamonds from the asthenosphere and the transition zone, lower mantle diamonds show a small shift towards isotopic heavy compositions (-6.6 to -0.5‰, mode at -3.5‰). As already observed for other mines, the nitrogen contents of lower mantle diamonds were below detection (using FTIRS). The mutual shift of sublithospheric diamonds towards

Pulsed laser deposition of metallic films on the surface of diamond particles for diamond saw blades

International Nuclear Information System (INIS)

Jiang Chao; Luo Fei; Long Hua; Hu Shaoliu; Li Bo; Wang Youqing

2005-01-01

Ti or Ni films have been deposited on the diamond particle surfaces by pulsed laser deposition. Compressive resistance of the uncoated and coated diamond particles was measured, respectively, in the experiments. The compressive resistance of the Ti-coated diamonds particles was found much higher than that of the uncoated ones. It increased by 39%. The surface morphology is observed by the metallography microscope. The surface of the uncoated diamonds particles had many hollows and flaws, while the surface of Ni-coated diamond particles was flat and smooth, and the surface of Ti-coated diamond particles had some metal masses that stood out of the surface of the Ti-coated film. The components of the metallic films of diamond particles were examined by X-ray diffractometry (XRD). TiC was found formed on the Ti-coated diamond surface, which resulted in increased surface bonding strength between the diamond particles and the Ti films. Meanwhile, TiC also favored improving the bonding strength between the coated diamond particles and the binding materials. Moreover, the bending resistance of the diamond saw blade made of Ti-coated diamond was drastically higher than that of other diamond saw blades, which also played an important role in improving the blade's cutting ability and lifetime. Therefore, it was most appropriate that the diamond saw blade was made of Ti-coated diamond particles rather than other materials

PREFACE: Science's gem: diamond science 2009 Science's gem: diamond science 2009

Science.gov (United States)

Mainwood, Alison; Newton, Mark E.; Stoneham, Marshall

2009-09-01

Natural diamond has been valued for its appearance and mechanical properties for at least two thousand years. As a gem stone diamond is unsurpassed. However, scientific work, especially in the last 20 years, has demonstrated that diamond has numerous surprising properties and many unique ones. Some of the extreme properties have been known for many years, but the true scale of diamond's other highly desirable features is still only coming to light as control in the synthesis of diamond, and hence material perfection, improves. The ultimate prize for man-made diamond is surely not in the synthesis of gem stones, but in delivering technological solutions enabled by diamond to the challenges facing our society today. If the special properties are to be exploited to their full potential, at least four crucial factors must be considered. First, there must be sufficient scientific understanding of diamond to make applications effective, efficient and economical. Secondly, the means of fabrication and control of properties have to be achieved so that diamond's role can be optimised. Thirdly, it is not enough that its properties are superior to existing materials: they must be so much better that it is worth initiating new technologies to exploit them. Finally, any substantial applications will have to address the society's major needs worldwide. The clear technology drivers for the 21st century come from the biomedical technologies, the demand for energy subject to global constraints, and the information technologies, where perhaps diamond will provide the major enabling technology [1]. The papers in this volume concern the solid state physics of diamond, and primarily concern the first two factors: understanding, and control of properties. They address many of the outstanding basic problems, such as the identification of existing defects, which affect the material's properties, both desirable and less so. Regarding future substantial applications, one paper discusses

Thermally stable diamond brazing

Science.gov (United States)

Radtke, Robert P [Kingwood, TX

2009-02-10

A cutting element and a method for forming a cutting element is described and shown. The cutting element includes a substrate, a TSP diamond layer, a metal interlayer between the substrate and the diamond layer, and a braze joint securing the diamond layer to the substrate. The thickness of the metal interlayer is determined according to a formula. The formula takes into account the thickness and modulus of elasticity of the metal interlayer and the thickness of the TSP diamond. This prevents the use of a too thin or too thick metal interlayer. A metal interlayer that is too thin is not capable of absorbing enough energy to prevent the TSP diamond from fracturing. A metal interlayer that is too thick may allow the TSP diamond to fracture by reason of bending stress. A coating may be provided between the TSP diamond layer and the metal interlayer. This coating serves as a thermal barrier and to control residual thermal stress.

Richard Peters and Valuing Authenticity

Science.gov (United States)

Degenhardt, M. A. B.

2009-01-01

Richard Peters has been praised for the authenticity of his philosophy, and inquiry into aspects of the development of his philosophy reveals a profound authenticity. Yet authenticity is something he seems not to favour. The apparent paradox is resolved by observing historical changes in the understanding of authenticity as an important value.…

Diamond growth on an array of seeds: The revolution of diamond production

Energy Technology Data Exchange (ETDEWEB)

Sung, James C. [KINIK Company, 64, Chung-San Rd., Ying-Kuo, Taipei Hsien 239, Taiwan (China) and National Taiwan University, Taipei 106, Taiwan (China) and National Taipei University of Technology, Taipei 106, Taiwan (China)]. E-mail: sung@kinik.com.tw; Sung, Michael [Massachusetts Institute of Technology, Cambridge, MA (United States); Sung, Emily [Johnson and Johnson, Freemont, CA (United States)

2006-03-01

The consumption of saw diamond grits is a measure of a nation's constructional activities. The per capita consumption for the world is about 0.7 carats in 2004, and in China, about 3 carats. The manufacture of large saw diamond grits requires stringent control of pressure and temperature that only a few companies can master. However, with the implementation of a novel diamond seeding technology, large saw diamond grits of extreme quality can be mass produced. With this breakthrough, the prices of saw grit will plummet in the near future that should benefit the constructional industry worldwide. Moreover, electronic or thermal grade of large diamond crystals may be produced for applications in semiconductor, electronic or optical industry.

Diamond growth on an array of seeds: The revolution of diamond production

International Nuclear Information System (INIS)

Sung, James C.; Sung, Michael; Sung, Emily

2006-01-01

The consumption of saw diamond grits is a measure of a nation's constructional activities. The per capita consumption for the world is about 0.7 carats in 2004, and in China, about 3 carats. The manufacture of large saw diamond grits requires stringent control of pressure and temperature that only a few companies can master. However, with the implementation of a novel diamond seeding technology, large saw diamond grits of extreme quality can be mass produced. With this breakthrough, the prices of saw grit will plummet in the near future that should benefit the constructional industry worldwide. Moreover, electronic or thermal grade of large diamond crystals may be produced for applications in semiconductor, electronic or optical industry

Distribution of Lygosoma guentheri (Peter, 1879 (Reptilia: Scincidae in Andhra Pradesh, India

Directory of Open Access Journals (Sweden)

S.M.M. Javed

2010-04-01

Full Text Available Lygosoma guentheri (Peter, 1879, hitherto a Western Ghats endemic species, has been recently recorded from the central Eastern Ghats of Andhra Pradesh based on a specimen collected in the Nallamalai Hills in 2003. Our herpetological surveys in Andhra Pradesh reveal the presence of Lygosoma guentheri (Peter, 1879 in a few more localities other than the Nallamalai Hills. This paper deals with the distribution and status of Lygosoma guentheri (Peter, 1879 in Andhra Pradesh based on recent sightings and collections.

Against the Corporate Culture Ideology: An Interview with Peter Mayo

Science.gov (United States)

Suoranta, Juha

2010-01-01

This article presents an interview with Peter Mayo, author and expert in the field of sociology of adult education, on his major influences in this area, his books, and his views on the role of radical adult education and radical scholarship in the future. In the interview, Peter Mayo states that his initial view of adult education was quite a…

Peter as character in the Gospel of Matthew: complexity and inversion

Directory of Open Access Journals (Sweden)

João Leonel

2014-03-01

Full Text Available This article focuses on the apostle Peter as a character in the Gospel of Matthew.  It aims at identifying the nuances and changes of the character Peter in the Gospel. For this purpose, I take as a starting point that the gospel belongs to the literary genre of ancient Greco-Roman Biography, which presents Jesus Christ as the protagonist. The other characters are developed in relationship with him. The same is true with the Apostle Peter. The article unfolds from narrative theory, in particular the categorization of characters. I categorize, based on Erich Auerbach and Robert Alter, the features of biblical characters, developing comparisons with theories of the character in the modern novel. The analysis of the main texts from the Gospel of Matthew that portray the character Peter leads to the conclusion that its main features are complexity and inversion. They produce an overview of the involution of the character in the narrative of the Gospel of Matthew.

Plastiliinivõlur Peter Lord / Margit Tõnson

Index Scriptorium Estoniae

Tõnson, Margit, 1978-

2007-01-01

PÖFFi animafilmide festivali "Animated Dreams" ja Nukufilmi 50. juubeli külaline, Bristolis asuva kuulsa Aardman Studio asutajaid ja režissöör Peter Lord oma stuudiost. Lisaks "Jumal on suur animaator, animaator on väike jumal"

An Interview with Peter MacDonald.

Science.gov (United States)

American Indian Journal, 1979

1979-01-01

Peter MacDonald, Chairman of the Navajo Nation, the largest tribe in the United States speaks to such issues as energy development/management, oil companies, Navajo-Hopi relocation legislation, traditionalism, and the role of the Council of Energy Resource Tribes. (RTS)

Diamond-cleaning investigations

International Nuclear Information System (INIS)

Derry, T.E.

Four parcels of diamonds which either had or had not been cleaned using the usual techniques, chiefly involving etch in molten potassium nitrate were supplied by De Beers Diamond Research Laboratories. Each parcel contained about 40 stones, amounting to about 10 carats. Half the diamonds in each parcel were cleaned by a standard procedure involving half an hours ultrasonic agitation in a 20% solution of the commercial detergent 'Contrad' which is effectively a surfactant and chelating agent. Visual comparisons by a number of observers who were not told the stones' histories, established that these diamonds generally had a more sparkling appearance after the cleaning procedure had been applied

Peter Standley 1924 – 2003

CERN Multimedia

2003-01-01

Peter Standley was one of the very early members of CERN staff. He joined CERN nearly 50 years ago and retired 20 years ago. Peter had been reading physics at Oxford University; that made him, in times of the second world war, an obvious candidate to work on the newly invented radar techniques and, as radar officer, he became a member of the Royal Navy. After demobilisation, he was attracted, like many of those working in the radar field, by the construction of particle accelerators, preparing his thesis on the 125 MeV electron synchrotron at the Clarendon Laboratory at Oxford. There he became involved in a fantastic, at that time almost unimaginable emerging project, for a European Laboratory, later to be called CERN. In 1954, he was nominated linkman between CERN and the company (Metropolitan Vickers), which had obtained the contract for the construction of the linear accelerator for the proton synchrotron, the PS, which was the first large project and "raison d'être" of the new ...

Diamond pixel modules

International Nuclear Information System (INIS)

Asner, D.; Barbero, M.; Bellini, V.; Belyaev, V.; Brom, J-M.; Bruzzi, M.; Chren, D.; Cindro, V.; Claus, G.; Cristinziani, M.; Costa, S.; D'Alessandro, R.; Boer, W. de; Dobos, D.; Dolenc, I.; Dulinski, W.; Duris, J.; Eremin, V.; Eusebi, R.; Frais-Koelbl, H.

2011-01-01

With the commissioning of the LHC in 2010 and upgrades expected in 2015, ATLAS and CMS are planning to upgrade their innermost tracking layers with radiation hard technologies. Chemical Vapor Deposition diamond has been used extensively in beam conditions monitors as the innermost detectors in the highest radiation areas of BaBar, Belle, CDF and all LHC experiments. This material is now being considered as a sensor material for use very close to the interaction region where the most extreme radiation conditions exist. Recently the RD42 collaboration constructed, irradiated and tested polycrystalline and single-crystal chemical vapor deposition diamond sensors to the highest fluences expected at the super-LHC. We present beam test results of chemical vapor deposition diamond up to fluences of 1.8x10 16 protons/cm 2 illustrating that both polycrystalline and single-crystal chemical vapor deposition diamonds follow a single damage curve. We also present beam test results of irradiated complete diamond pixel modules.

Diamond pixel modules

Energy Technology Data Exchange (ETDEWEB)

Asner, D. [Carleton University, Ottawa (Canada); Barbero, M. [Universitaet Bonn (Germany); Bellini, V. [INFN/University of Catania (Italy); Belyaev, V. [MEPHI Institute, Moscow (Russian Federation); Brom, J-M. [IPHC, Strasbourg (France); Bruzzi, M. [INFN/University of Florence (Italy); Chren, D. [Czech Technical University, Prague (Czech Republic); Cindro, V. [Jozef Stefan Institute, Ljubljana (Slovenia); Claus, G. [IPHC, Strasbourg (France); Cristinziani, M. [Universitaet Bonn (Germany); Costa, S. [INFN/University of Catania (Italy); D' Alessandro, R. [Department of Energetics/INFN Florence (Italy); Boer, W. de [Universitaet Karlsruhe, Karlsruhe (Germany); Dobos, D. [CERN, Geneva (Switzerland); Dolenc, I. [Jozef Stefan Institute, Ljubljana (Slovenia); Dulinski, W. [IPHC, Strasbourg (France); Duris, J. [UCLA, Los Angeles, CA (United States); Eremin, V. [Ioffe Institute, St. Petersburg (Russian Federation); Eusebi, R. [FNAL, Batavia (United States); Frais-Koelbl, H. [Fachhochschule fuer Wirtschaft und Technik, Wiener Neustadt (Austria)

2011-04-21

With the commissioning of the LHC in 2010 and upgrades expected in 2015, ATLAS and CMS are planning to upgrade their innermost tracking layers with radiation hard technologies. Chemical Vapor Deposition diamond has been used extensively in beam conditions monitors as the innermost detectors in the highest radiation areas of BaBar, Belle, CDF and all LHC experiments. This material is now being considered as a sensor material for use very close to the interaction region where the most extreme radiation conditions exist. Recently the RD42 collaboration constructed, irradiated and tested polycrystalline and single-crystal chemical vapor deposition diamond sensors to the highest fluences expected at the super-LHC. We present beam test results of chemical vapor deposition diamond up to fluences of 1.8x10{sup 16} protons/cm{sup 2} illustrating that both polycrystalline and single-crystal chemical vapor deposition diamonds follow a single damage curve. We also present beam test results of irradiated complete diamond pixel modules.

Diamond nanophotonics

Directory of Open Access Journals (Sweden)

Katja Beha

2012-12-01

Full Text Available We demonstrate the coupling of single color centers in diamond to plasmonic and dielectric photonic structures to realize novel nanophotonic devices. Nanometer spatial control in the creation of single color centers in diamond is achieved by implantation of nitrogen atoms through high-aspect-ratio channels in a mica mask. Enhanced broadband single-photon emission is demonstrated by coupling nitrogen–vacancy centers to plasmonic resonators, such as metallic nanoantennas. Improved photon-collection efficiency and directed emission is demonstrated by solid immersion lenses and micropillar cavities. Thereafter, the coupling of diamond nanocrystals to the guided modes of micropillar resonators is discussed along with experimental results. Finally, we present a gas-phase-doping approach to incorporate color centers based on nickel and tungsten, in situ into diamond using microwave-plasma-enhanced chemical vapor deposition. The fabrication of silicon–vacancy centers in nanodiamonds by microwave-plasma-enhanced chemical vapor deposition is discussed in addition.

The Peters' plus syndrome: a review

NARCIS (Netherlands)

Maillette de Buy Wenniger-Prick, Liesbeth J. J. M.; Hennekam, Raoul C. M.

2002-01-01

Peters' plus syndrome is an infrequently described entity that combines anomalies in the anterior chamber of the eye with other multiple congenital anomalies, and a developmental delay. Major symptoms are extremely variable anterior chamber anomalies, cupid bow of the upper lip, cleft lip and

Acute toxicity of Headline® fungicide to Blanchard's cricket frogs (Acris blanchardi).

Science.gov (United States)

Cusaac, J Patrick W; Morrison, Shane A; Belden, Jason B; Smith, Loren M; McMurry, Scott T

2016-04-01

Previous laboratory studies have suggested that pyraclostrobin-containing fungicide formulations are toxic to amphibians at environmentally relevant concentrations. However, it is unknown if all pyraclostrobin formulations have similar toxicity and if toxicity occurs in different amphibian species. We investigated the acute toxicity of two formulations, Headline(®) fungicide and Headline AMP(®) fungicide, to Blanchard's cricket frogs (Acris blanchardi) based on a direct overspray scenario. In addition, we examined body residues of fungicide active ingredients in A. blanchardi following direct exposure to Headline AMP fungicide. Headline fungicide and Headline AMP fungicide had similar toxicity to A. blanchardi with calculated median lethal doses of 2.1 and 1.7 µg pyraclostrobin/cm(2), respectively, which are similar to the suggested maximum label rate in North American corn (2.2 and 1.52 µg pyraclostrobin/cm(2), respectively). Tissue concentrations of pyraclostrobin were lower than predicted based on full uptake of a direct dose, and did not drop during the first 24 h after exposure. Headline fungicides at corn application rates are acutely toxic to cricket frogs, but acute toxicity in the field will depend on worst-case exposure.

Optical engineering of diamond

CERN Document Server

Rabeau, James R

2013-01-01

This is the first comprehensive book on the engineering of diamond optical devices. It will give readers an up-to-date account of the properties of optical quality synthetic diamond (single crystal, nanodiamond and polycrystalline) and reviews the large and growing field of engineering of diamond-based optical devices, with applications in quantum computation, nano-imaging, high performance lasers, and biomedicine. It aims to provide scientists, engineers and physicists with a valuable resource and reference book for the design and performance of diamond-based optical devices.

Status and applications of diamond and diamond-like materials: An emerging technology

Science.gov (United States)

1990-01-01

Recent discoveries that make possible the growth of crystalline diamond by chemical vapor deposition offer the potential for a wide variety of new applications. This report takes a broad look at the state of the technology following from these discoveries in relation to other allied materials, such as high-pressure diamond and cubic boron nitride. Most of the potential defense, space, and commercial applications are related to diamond's hardness, but some utilize other aspects such as optical or electronic properties. The growth processes are reviewed, and techniques for characterizing the resulting materials' properties are discussed. Crystalline diamond is emphasized, but other diamond-like materials (silicon carbide, amorphous carbon containing hydrogen) are also examined. Scientific, technical, and economic problem areas that could impede the rapid exploitation of these materials are identified. Recommendations are presented covering broad areas of research and development.

Peter Waterman and T-Matrix Methods

Science.gov (United States)

Mishchenko, M. I.; Martin, P.A.

2013-01-01

This paper summarizes the scientific legacy of Peter C. Waterman (1928-2012) who introduced concepts and theoretical techniques that have had a major impact on the fields of scattering by particles and particle groups, optical particletcharacterization, radiative transfer, and remote sensing. A biographical sketch is also included.

Prince Peter's 7 years in Kalimpong

DEFF Research Database (Denmark)

Brox, Trine; Zeitzen, Miriam Koktvedgaard

2017-01-01

and document empty spots on the map and to rescue the remnants of local cultures in Upper Asia. With the developing crisis in Tibet, however, Prince Peter was stranded in Kalimpong, waiting in vain for permission to enter Tibet. Yet unfavourable political circumstances turned into great opportunities...

Ripples from a Passing Ship: Memories; and a Legacy of Richard Peters

Science.gov (United States)

Harris, Kevin

2013-01-01

This paper outlines aspects and dimensions of my "relationship" with Richard Peters from 1966 onward. The underlying suggestion is that, while Peters' contribution to philosophy of education was undeniably of major proportions, both that contribution and his legacy are institutional rather than substantive. (Contains 15 notes.)

A Conversation with Peter Senge: Transforming Organizational Cultures

Directory of Open Access Journals (Sweden)

Riane Eisler

2015-07-01

Full Text Available Riane Eisler talks with Peter Senge, internationally renowned expert on management and organizational leadership, about transforming organizational cultures from domination to partnership.

Thermal applications of low-pressure diamond

International Nuclear Information System (INIS)

Haubner, R.; Lux, B.

1997-01-01

During the last decade several applications of low-pressure diamond were developed. Main products are diamond heat-spreaders using its high thermal conductivity, diamond windows with their high transparency over a wide range of wavelengths and wear resistant tool coatings because of diamonds superhardness. A short description of the most efficient diamond deposition methods (microwave, DC-glow discharge, plasma-jet and arc discharge) is given. The production and applications of diamond layers with high thermal conductivity will be described. Problems of reproducibility of diamond deposition, the influence of impurities, the heat conductivity in electronic packages, reliability and economical mass production will be discussed. (author)

Investigation of the physics of diamond MEMS : diamond allotrope lithography

International Nuclear Information System (INIS)

Zalizniak, I.; Olivero, P.; Jamieson, D.N.; Prawer, S.; Reichart, P.; Rubanov, S.; Petriconi, S.

2005-01-01

We propose a novel lithography process in which ion induced phase transfomations of diamond form sacrificial layers allowing the fabrication of small structures including micro-electromechanical systems (MEMS). We have applied this novel lithography to the fabrication of diamond microcavities, cantilevers and optical waveguides. In this paper we present preliminary experiments directed at the fabrication of suspended diamond disks that have the potential for operation as optical resonators. Such structures would be very durable and resistant to chemical attack with potential applications as novel sensors for extreme environments or high temperature radiation detectors. (author). 3 refs., 3 figs

Workshop on diamond and diamond-like-carbon films for the transportation industry

Energy Technology Data Exchange (ETDEWEB)

Nichols, F.A.; Moores, D.K. [eds.

1993-01-01

Applications exist in advanced transportation systems as well as in manufacturing processes that would benefit from superior tribological properties of diamond, diamond-like-carbon and cubic boron nitride coatings. Their superior hardness make them ideal candidates as protective coatings to reduce adhesive, abrasive and erosive wear in advanced diesel engines, gas turbines and spark-ignited engines and in machining and manufacturing tools as well. The high thermal conductivity of diamond also makes it desirable for thermal management not only in tribological applications but also in high-power electronic devices and possibly large braking systems. A workshop has been recently held at Argonne National Laboratory entitled ``Diamond and Diamond-Like-Carbon Films for Transportation Applications`` which was attended by 85 scientists and engineers including top people involved in the basic technology of these films and also representatives from many US industrial companies. A working group on applications endorsed 18 different applications for these films in the transportation area alone. Separate abstracts have been prepared.

Electrochemical applications of CVD diamond

International Nuclear Information System (INIS)

Pastor-Moreno, Gustavo

2002-01-01

Diamond technology has claimed an important role in industry since non-expensive methods of synthesis such as chemical vapour deposition allow to elaborate cheap polycrystalline diamond. This fact has increased the interest in the scientific community due to the outstanding properties of diamond. Since Pleskov published in 1987 the first paper in electrochemistry, many researchers around the world have studied different aspects of diamond electrochemistry such as reactivity, electrical structure, etc. As part of this worldwide interest these studies reveal new information about diamond electrodes. These studies report investigation of diamond electrodes characterized using structural techniques like scanning electrode microscopy and Raman spectroscopy. A new electrochemical theory based on surface states is presented that explains the metal and the semiconductor behaviour in terms of the doping level of the diamond electrode. In an effort to characterise the properties of diamond electrodes the band edges for hydrogen and oxygen terminated surface are located in organic solvent, hence avoiding possible interference that are present in aqueous solution. The determination of the band edges is performed by Mott-Schottky studies. These allow the calculation of the flat band potential and therefore the band edges. Additional cyclic voltammetric studies are presented for both types of surface termination. Mott-Schottky data and cyclic voltammograms are compared and explained in terms of the band edge localisation. Non-degenerately p-type semiconductor behaviour is presented for hydrogen terminated boron doped diamond. Graphitic surface states on oxidised surface boron doped diamond are responsible for the electrochemistry of redox couples that posses similar energy. Using the simple redox couple 1,4-benzoquinone effect of surface termination on the chemical behaviour of diamond is presented. Hydrogen sublayers in diamond electrodes seem to play an important role for the

Peter Greenaway klaarib kunstiajalooga arveid / Johannes Saar

Index Scriptorium Estoniae

Saar, Johannes, 1965-

2009-01-01

Peter Greenaway multimeediainstallatsioon seeriast "Üheksa klassikalist maali" Paolo Veronese maalist "Kaana pulm" San Giorgio Maggiore kloostris Venezias 6. juunist 13. septembrini. Kloostri söögisaali otsaseinal on Paolo Veronese maali "Kaana pulm" 2007. a. valminud koopia

Diamond-based materials for biomedical applications

CERN Document Server

Narayan, Roger

2013-01-01

Carbon is light-weight, strong, conductive and able to mimic natural materials within the body, making it ideal for many uses within biomedicine. Consequently a great deal of research and funding is being put into this interesting material with a view to increasing the variety of medical applications for which it is suitable. Diamond-based materials for biomedical applications presents readers with the fundamental principles and novel applications of this versatile material. Part one provides a clear introduction to diamond based materials for medical applications. Functionalization of diamond particles and surfaces is discussed, followed by biotribology and biological behaviour of nanocrystalline diamond coatings, and blood compatibility of diamond-like carbon coatings. Part two then goes on to review biomedical applications of diamond based materials, beginning with nanostructured diamond coatings for orthopaedic applications. Topics explored include ultrananocrystalline diamond for neural and ophthalmologi...

Homo-epitaxial diamond film growth on ion implanted diamond substrates

Energy Technology Data Exchange (ETDEWEB)

Weiser, P S; Prawer, S; Nugent, K W; Bettiol, A A; Kostidis, L I; Jamieson, D N [Melbourne Univ., Parkville, VIC (Australia). School of Physics

1997-12-31

The nucleation of CVD diamond is a complicated process, governed by many interrelated parameters. In the present work we attempt to elucidate the effect of strain on the growth of a homo-epitaxial CVD diamond. We have employed laterally confined high dose (MeV) Helium ion implantation to produce surface swelling of the substrate. The strain is enhanced by the lateral confinement of the implanted region to squares of 100 x 100 {mu}m{sup 2}. After ion implantation, micro-Raman spectroscopy was employed to map the surface strain. The substrates were then inserted into a CVD reactor and a CVD diamond film was grown upon them. Since the strained regions were laterally confined, it was then possible to monitor the effect of strain on diamond nucleation. The substrates were also analysed using Rutherford Backscattering Spectroscopy (RBS), Proton induced X-ray Emission (PIXE) and Ion Beam induced Luminescence (IBIL). 7 refs., 5 figs.

Homo-epitaxial diamond film growth on ion implanted diamond substrates

Energy Technology Data Exchange (ETDEWEB)

Weiser, P.S.; Prawer, S.; Nugent, K.W.; Bettiol, A.A.; Kostidis, L.I.; Jamieson, D.N. [Melbourne Univ., Parkville, VIC (Australia). School of Physics

1996-12-31

The nucleation of CVD diamond is a complicated process, governed by many interrelated parameters. In the present work we attempt to elucidate the effect of strain on the growth of a homo-epitaxial CVD diamond. We have employed laterally confined high dose (MeV) Helium ion implantation to produce surface swelling of the substrate. The strain is enhanced by the lateral confinement of the implanted region to squares of 100 x 100 {mu}m{sup 2}. After ion implantation, micro-Raman spectroscopy was employed to map the surface strain. The substrates were then inserted into a CVD reactor and a CVD diamond film was grown upon them. Since the strained regions were laterally confined, it was then possible to monitor the effect of strain on diamond nucleation. The substrates were also analysed using Rutherford Backscattering Spectroscopy (RBS), Proton induced X-ray Emission (PIXE) and Ion Beam induced Luminescence (IBIL). 7 refs., 5 figs.

Homo-epitaxial diamond film growth on ion implanted diamond substrates

International Nuclear Information System (INIS)

Weiser, P.S.; Prawer, S.; Nugent, K.W.; Bettiol, A.A.; Kostidis, L.I.; Jamieson, D.N.

1996-01-01

The nucleation of CVD diamond is a complicated process, governed by many interrelated parameters. In the present work we attempt to elucidate the effect of strain on the growth of a homo-epitaxial CVD diamond. We have employed laterally confined high dose (MeV) Helium ion implantation to produce surface swelling of the substrate. The strain is enhanced by the lateral confinement of the implanted region to squares of 100 x 100 μm 2 . After ion implantation, micro-Raman spectroscopy was employed to map the surface strain. The substrates were then inserted into a CVD reactor and a CVD diamond film was grown upon them. Since the strained regions were laterally confined, it was then possible to monitor the effect of strain on diamond nucleation. The substrates were also analysed using Rutherford Backscattering Spectroscopy (RBS), Proton induced X-ray Emission (PIXE) and Ion Beam induced Luminescence (IBIL). 7 refs., 5 figs

Peter and Louise: Being Clergy in a Secularized World

DEFF Research Database (Denmark)

Leth-Nissen, Karen Marie

2016-01-01

of a continuum of churches, with the very ecclesial at one end and the very societal at the other. Both Louise and Peter experience the pressure of simultaneous expectations from the church as an institution, the church as a community, and the society in which they are embedded. Understanding how Peter......’ doctrines on what it means to be a true church. Together, these implicit and explicit theologies (Percy 2010) will inform us about the ecclesiologies of the churches today; how they are being the church. The analysis will explain some of the differences between these two majority churches and how...

Phosphorylated nano-diamond/ Polyimide Nanocomposites

International Nuclear Information System (INIS)

Beyler-Çiǧil, Asli; Çakmakçi, Emrah; Kahraman, Memet Vezir

2014-01-01

In this study, a novel route to synthesize polyimide (PI)/phosphorylated nanodiamond films with improved thermal and mechanical properties was developed. Surface phosphorylation of nano-diamond was performed in dichloromethane. Phosphorylation dramatically enhanced the thermal stability of nano-diamond. Poly(amic acid) (PAA), which is the precursor of PI, was successfully synthesized with 3,3',4,4'-Benzophenonetetracarboxylic dianhydride (BTDA) and 4,4'-oxydianiline (4,4'-ODA) in the solution of N,N- dimethylformamide (DMF). Pure BTDA-ODA polyimide films and phosphorylated nanodiamond containing BTDA-ODA PI films were prepared. The PAA displayed good compatibility with phosphorylated nano-diamond. The morphology of the polyimide (PI)/phosphorylated nano-diamond was characterized by scanning electron microscopy (SEM). Chemical structure of polyimide and polyimide (PI)/phosphorylated nano-diamond was characterized by FTIR. SEM and FTIR results showed that the phosphorylated nano-diamond was successfully prepared. Thermal properties of the polyimide (PI)/phosphorylated nanodiamond was characterized by thermogravimetric analysis (TGA). TGA results showed that the thermal stability of (PI)/phosphorylated nano-diamond film was increased

Nanocrystalline diamond coatings for machining

Energy Technology Data Exchange (ETDEWEB)

Frank, M.; Breidt, D.; Cremer, R. [CemeCon AG, Wuerselen (Germany)

2007-07-01

This history of CVD diamond synthesis goes back to the fifties of the last century. However, the scientific and economical potential was only gradually recognized. In the eighties, intensive worldwide research on CVD diamond synthesis and applications was launched. Industrial products, especially diamond-coated cutting tools, were introduced to the market in the middle of the nineties. This article shows the latest developments in this area, which comprises nanocrystalline diamond coating structures. (orig.)

Peter Carravetta, Del postmoderno.

Directory of Open Access Journals (Sweden)

Alessandro Carrera

2010-08-01

Full Text Available Peter Carravetta, professor of “Italian and Italian American Studies” at SUNY Stony Brook, with an Italian and American education, has put together in his massive Del postmoderno possibly the most complete critical review so far of American academic production from the 1970s to the present. “Postmodern” is the key word of the cultural turn that took place between the 1950s and the 1970s only to meet its death, in Carravetta’s opinion, on September 11, 2001, when the shortlived illusion that h...

Peter Koch: wizard of wood use

Science.gov (United States)

M.E. Lora

1978-01-01

Like his pioneer forefathers, Peter Koch sees opportunity where others see obstacles. And his vision is helping to reshape the wood industry. Since 1963 Koch has directed research on processing southern woods for the U.S. Forest Service's Southern Forest Experiment Station in Pineville, Louisiana. In that time, he has invented six revolutionary machines, developed...

Diamond: a material for acoustic devices

OpenAIRE

MORTET, Vincent; WILLIAMS, Oliver; HAENEN, Ken

2008-01-01

Diamond has been foreseen to replace silicon for high power, high frequency electronic applications or for devices that operates in harsh environments. However, diamond electronic devices are still in the laboratory stage due to the lack of large substrates and the complexity of diamond doping. On another hand, surface acoustic wave filters based on diamond are commercially available. Diamond is especially suited for acoustic applications because of its exceptional mechanical properties. The ...

Ion implantation into diamond

International Nuclear Information System (INIS)

Sato, Susumu

1994-01-01

The graphitization and the change to amorphous state of diamond surface layer by ion implantation and its characteristics are reported. In the diamond surface, into which more than 10 16 ions/cm 2 was implanted, the diamond crystals are broken, and the structure changes to other carbon structure such as amorphous state or graphite. Accompanying this change of structure, the electric conductivity of the implanted layer shows two discontinuous values due to high resistance and low resistance. This control of structure can be done by the temperature of the base during the ion implantation into diamond. Also it is referred to that by the base temperature during implantation, the mutual change of the structure between amorphous state and graphite can be controlled. The change of the electric resistance and the optical characteristics by the ion implantation into diamond surface, the structural analysis by Raman spectroscopy, and the control of the structure of the implanted layer by the base temperature during implantation are reported. (K.I.)

Investing in Diamonds

NARCIS (Netherlands)

Renneboog, Luc

2015-01-01

This paper examines the risk-return characteristics of investment grade gems (white diamonds, colored diamonds and other types of gems including sapphires, rubies, and emeralds). The transactions are coming from gem auctions and span the period 1999-2012. Over our time frame, the annual nominal USD

Diamond Pixel Detectors

International Nuclear Information System (INIS)

Adam, W.; Berdermann, E.; Bergonzo, P.; Bertuccio, G.; Bogani, F.; Borchi, E.; Brambilla, A.; Bruzzi, M.; Colledani, C.; Conway, J.; D'Angelo, P.; Dabrowski, W.; Delpierre, P.; Deneuville, A.; Doroshenko, J.; Dulinski, W.; Eijk, B. van; Fallou, A.; Fizzotti, F.; Foster, J.; Foulon, F.; Friedl, M.; Gan, K.K.; Gheeraert, E.; Gobbi, B.; Grim, G.P.; Hallewell, G.; Han, S.; Hartjes, F.; Hrubec, J.; Husson, D.; Kagan, H.; Kania, D.; Kaplon, J.; Kass, R.; Koeth, T.; Krammer, M.; Lander, R.; Logiudice, A.; Lu, R.; Lynne, L.M.; Manfredotti, C.; Meier, D.; Mishina, M.; Moroni, L.; Oh, A.; Pan, L.S.; Pernicka, M.; Perera, L.; Pirollo, S.; Plano, R.; Procario, M.; Riester, J.L.; Roe, S.; Rott, C.; Rousseau, L.; Rudge, A.; Russ, J.; Sala, S.; Sampietro, M.; Schnetzer, S.; Sciortino, S.; Stelzer, H.; Stone, R.; Suter, B.; Tapper, R.J.; Tesarek, R.; Trischuk, W.; Tromson, D.; Vittone, E.; Wedenig, R.; Weilhammer, P.; White, C.; Zeuner, W.; Zoeller, M.

2001-01-01

Diamond based pixel detectors are a promising radiation-hard technology for use at the LHC. We present first results on a CMS diamond pixel sensor. With a threshold setting of 2000 electrons, an average pixel efficiency of 78% was obtained for normally incident minimum ionizing particles

Diamond Pixel Detectors

Energy Technology Data Exchange (ETDEWEB)

Adam, W.; Berdermann, E.; Bergonzo, P.; Bertuccio, G.; Bogani, F.; Borchi, E.; Brambilla, A.; Bruzzi, M.; Colledani, C.; Conway, J.; D' Angelo, P.; Dabrowski, W.; Delpierre, P.; Deneuville, A.; Doroshenko, J.; Dulinski, W.; Eijk, B. van; Fallou, A.; Fizzotti, F.; Foster, J.; Foulon, F.; Friedl, M.; Gan, K.K.; Gheeraert, E.; Gobbi, B.; Grim, G.P.; Hallewell, G.; Han, S.; Hartjes, F.; Hrubec, J.; Husson, D.; Kagan, H.; Kania, D.; Kaplon, J.; Kass, R.; Koeth, T.; Krammer, M.; Lander, R.; Logiudice, A.; Lu, R.; Lynne, L.M.; Manfredotti, C.; Meier, D.; Mishina, M.; Moroni, L.; Oh, A.; Pan, L.S.; Pernicka, M.; Perera, L. E-mail: perera@physics.rutgers.edu; Pirollo, S.; Plano, R.; Procario, M.; Riester, J.L.; Roe, S.; Rott, C.; Rousseau, L.; Rudge, A.; Russ, J.; Sala, S.; Sampietro, M.; Schnetzer, S.; Sciortino, S.; Stelzer, H.; Stone, R.; Suter, B.; Tapper, R.J.; Tesarek, R.; Trischuk, W.; Tromson, D.; Vittone, E.; Wedenig, R.; Weilhammer, P.; White, C.; Zeuner, W.; Zoeller, M

2001-06-01

Diamond based pixel detectors are a promising radiation-hard technology for use at the LHC. We present first results on a CMS diamond pixel sensor. With a threshold setting of 2000 electrons, an average pixel efficiency of 78% was obtained for normally incident minimum ionizing particles.

Quantum photonic networks in diamond

KAUST Repository

Lončar, Marko

2013-02-01

Advances in nanotechnology have enabled the opportunity to fabricate nanoscale optical devices and chip-scale systems in diamond that can generate, manipulate, and store optical signals at the single-photon level. In particular, nanophotonics has emerged as a powerful interface between optical elements such as optical fibers and lenses, and solid-state quantum objects such as luminescent color centers in diamond that can be used effectively to manipulate quantum information. While quantum science and technology has been the main driving force behind recent interest in diamond nanophotonics, such a platform would have many applications that go well beyond the quantum realm. For example, diamond\\'s transparency over a wide wavelength range, large third-order nonlinearity, and excellent thermal properties are of great interest for the implementation of frequency combs and integrated Raman lasers. Diamond is also an inert material that makes it well suited for biological applications and for devices that must operate in harsh environments. Copyright © Materials Research Society 2013.

Peter Taylor | IDRC - International Development Research Centre

International Development Research Centre (IDRC) Digital Library (Canada)

He leads a multidisciplinary team that strengthens policy research capacity in developing countries on issues of economic policy, governance, and health systems. Peter has more than 30 years of experience in international development, including positions at the Institute of Development Studies, UK; Helvetas Vietnam; ...

SuchThatCast Episode 5: Peter Asaro

NARCIS (Netherlands)

Soraker, Johnny

2012-01-01

Peter Asaro is Assistant Professor at the School of Media Studies in the New School for Public Engagement, New York, specializing in philosophy of science, technology and media. His work examines the interfaces between social relations, human minds and bodies, artificial intelligence and robotics,

Tracing the depositional history of Kalimantan diamonds by zircon provenance and diamond morphology studies

Science.gov (United States)

Kueter, Nico; Soesilo, Joko; Fedortchouk, Yana; Nestola, Fabrizio; Belluco, Lorenzo; Troch, Juliana; Wälle, Markus; Guillong, Marcel; Von Quadt, Albrecht; Driesner, Thomas

2016-11-01

Diamonds in alluvial deposits in Southeast Asia are not accompanied by indicator minerals suggesting primary kimberlite or lamproite sources. The Meratus Mountains in Southeast Borneo (Province Kalimantan Selatan, Indonesia) provide the largest known deposit of these so-called "headless" diamond deposits. Proposals for the origin of Kalimantan diamonds include the adjacent Meratus ophiolite complex, ultra-high pressure (UHP) metamorphic terranes, obducted subcontinental lithospheric mantle and undiscovered kimberlite-type sources. Here we report results from detailed sediment provenance analysis of diamond-bearing Quaternary river channel material and from representative outcrops of the oldest known formations within the Alino Group, including the diamond-bearing Campanian-Maastrichtian Manunggul Formation. Optical examination of surfaces of diamonds collected from artisanal miners in the Meratus area (247 stones) and in West Borneo (Sanggau Area, Province Kalimantan Barat; 85 stones) points toward a classical kimberlite-type source for the majority of these diamonds. Some of the diamonds host mineral inclusions suitable for deep single-crystal X-ray diffraction investigation. We determined the depth of formation of two olivines, one coesite and one peridotitic garnet inclusion. Pressure of formation estimates for the peridotitic garnet at independently derived temperatures of 930-1250 °C are between 4.8 and 6.0 GPa. Sediment provenance analysis includes petrography coupled to analyses of detrital garnet and glaucophane. The compositions of these key minerals do not indicate kimberlite-derived material. By analyzing almost 1400 zircons for trace element concentrations with laser ablation ICP-MS (LA-ICP-MS) we tested the mineral's potential as an alternative kimberlite indicator. The screening ultimately resulted in a small subset of ten zircons with a kimberlitic affinity. Subsequent U-Pb dating resulting in Cretaceous ages plus a detailed chemical reflection make

Peter in the Gospel of Mark and in Early Christianity in Rome

DEFF Research Database (Denmark)

Willert, Niels

1997-01-01

Artiklen gennemgår Markusevangeliets portræt af apostlen Peter og drøfter spørgsmålet, hvorfor Peter er så negativt skildret hos Markus. Litterære og pædagogiske (indirekte formaning til datidens kristne) intentioner forklarer først og fremmest dette træk hos Markus. Men også historiske spørgsmål...

The Many Facets of Diamond Crystals

Directory of Open Access Journals (Sweden)

Yuri N. Palyanov

2018-01-01

Full Text Available This special issue is intended to serve as a multidisciplinary forum covering broad aspects of the science, technology, and application of synthetic and natural diamonds. This special issue contains 12 papers, which highlight recent investigations and developments in diamond research related to the diverse problems of natural diamond genesis, diamond synthesis and growth using CVD and HPHT techniques, and the use of diamond in both traditional applications, such as mechanical machining of materials, and the new recently emerged areas, such as quantum technologies. The results presented in the contributions collected in this special issue clearly demonstrate that diamond occupies a very special place in modern science and technology. After decades of research, this structurally very simple material still poses many intriguing scientific questions and technological challenges. It seems undoubted that diamond will remain the center of attraction for many researchers for many years to come.

76 FR 37684 - Airworthiness Directives; Diamond Aircraft Industries GmbH Model (Diamond) DA 40 Airplanes...

Science.gov (United States)

2011-06-28

... Industries GmbH Model (Diamond) DA 40 Airplanes Equipped With Certain Cabin Air Conditioning Systems AGENCY... inspections of the Diamond Model DA 40 airplanes equipped with a VCS installed per Premier Aircraft Service... GmbH Model (Diamond) DA 40 Airplanes Equipped With Certain Cabin Air Conditioning Systems: Docket No...

CERN through the lens of Peter Ginter

CERN Multimedia

2008-01-01

This summer, passers-by along the Quai Wilson on the banks of Lake Geneva will be able to enjoy an unusual exhibition of photographs devoted to CERN and the LHC. Fifty images from the work of Peter Ginter, organized into themes, give strollers on the Quai Wilson a glimpse of the unique human and scientific adventure at CERN. An exhibition panel, showing a scientist against the background of ALICE’s huge red electromagnet.CERN will reach an important milestone in 2008 with the start-up of the LHC, opening a new window on our Universe for physicists around the world. To celebrate this event with the people who live around Lake Geneva and visitors to the area, CERN and the city of Geneva are jointly putting on the photography exhibition "CERN through the lens of Peter Ginter", which opens on 29 May. A group of some fifty images taken by the German photo...

One step deposition of highly adhesive diamond films on cemented carbide substrates via diamond/β-SiC composite interlayers

Energy Technology Data Exchange (ETDEWEB)

Wang, Tao; Zhuang, Hao; Jiang, Xin, E-mail: xin.jiang@uni-siegen.de

2015-12-30

Graphical abstract: - Highlights: • Novel diamond/beta-silicon carbide composite gradient interlayers were synthesized. • The interlayer features a cross-sectional gradient with increasing diamond content. • Diamond top layers and the interlayers were deposited in one single process. • The adhesion of the diamond film is drastically improved by employing the interlayer. • The stress was suppressed by manipulating the distribution of diamond and silicon carbide. - Abstract: Deposition of adherent diamond films on cobalt-cemented tungsten carbide substrates has been realized by application of diamond/beta-silicon carbide composite interlayers. Diamond top layers and the interlayers were deposited in one single process by hot filament chemical vapor deposition technique. Two different kinds of interlayers have been employed, namely, gradient interlayer and interlayer with constant composition. The distribution of diamond and beta-silicon carbide phases was precisely controlled by manipulating the gas phase composition. X-ray diffraction and Raman spectroscopy were employed to determine the existence of diamond, beta-silicon carbide and cobalt silicides (Co{sub 2}Si, CoSi) phases, as well as the quality of diamond crystal and the residual stress in the films. Rockwell-C indentation tests were carried out to evaluate the film adhesion. It is revealed that the adhesion of the diamond film is drastically improved by employing the interlayer. This is mainly influenced by the residual stress in the diamond top layer, which is induced by the different thermal expansion coefficient of the film and the substrate. It is even possible to further suppress the stress by manipulating the distribution of diamond and beta-silicon carbide in the interlayer. The most adhesive diamond film on cemented carbide is thus obtained by employing a gradient composite interlayer.

A wear simulation study of nanostructured CVD diamond-on-diamond articulation involving concave/convex mating surfaces

Science.gov (United States)

Baker, Paul A.; Thompson, Raymond G.; Catledge, Shane A.

2015-01-01

Using microwave-plasma Chemical Vapor Deposition (CVD), a 3-micron thick nanostructured-diamond (NSD) layer was deposited onto polished, convex and concave components that were machined from Ti-6Al-4V alloy. These components had the same radius of curvature, 25.4mm. Wear testing of the surfaces was performed by rotating articulation of the diamond-deposited surfaces (diamond-on-diamond) with a load of 225N for a total of 5 million cycles in bovine serum resulting in polishing of the diamond surface and formation of very shallow, linear wear grooves of less than 50nm depth. The two diamond surfaces remained adhered to the components and polished each other to an average surface roughness that was reduced by as much as a factor of 80 for the most polished region located at the center of the condyle. Imaging of the surfaces showed that the initial wearing-in phase of diamond was only beginning at the end of the 5 million cycles. Atomic force microscopy, scanning electron microscopy, Raman spectroscopy, and surface profilometry were used to characterize the surfaces and verify that the diamond remained intact and uniform over the surface, thereby protecting the underlying metal. These wear simulation results show that diamond deposition on Ti alloy has potential application for joint replacement devices with improved longevity over existing devices made of cobalt chrome and ultra-high molecular weight polyethylene (UHMWPE). PMID:26989457

Diamond and diamond-like films for transportation applications

Energy Technology Data Exchange (ETDEWEB)

Perez, J.M.

1993-01-01

This section is a compilation of transparency templates which describe the goals of the Office of Transportation Materials (OTM) Tribology Program. The positions of personnel on the OTM are listed. The role and mission of the OTM is reviewed. The purpose of the Tribology Program is stated to be `to obtain industry input on program(s) in tribology/advanced lubricants areas of interest`. The objective addressed here is to identify opportunities for cost effective application of diamond and diamond-like carbon in transportation systems.

CVD diamond substrates for electronic devices

International Nuclear Information System (INIS)

Holzer, H.

1996-03-01

In this study the applicability of chemical vapor deposition (CVD) diamond as a material for heat spreaders was investigated. Economical evaluations on the production of heat spreaders were also performed. For the diamond synthesis the hot-filament and microwave method were used respectively. The deposition parameters were varied in a way that free standing diamond layers with a thickness of 80 to 750 microns and different qualities were obtained. The influence of the deposition parameters on the relevant film properties was investigated and discussed. With both the hot-filament and microwave method it was possible to deposit diamond layers having a thermal conductivity exceeding 1200 W/mK and therefore to reach the quality level for commercial uses. The electrical resistivity was greater than 10 12 Ωcm. The investigation of the optical properties was done by Raman-, IR- and cathodoluminescence spectroscopy. Because of future applications of diamond-aluminium nitride composites as highly efficient heat spreaders diamond deposition an AIN was investigated. An improved substrate pretreatment prior to diamond deposition showed promising results for better performance of such composite heat spreaders. Both free standing layers and diamond-AIN composites could be cut by a CO2 Laser in Order to get an exact size geometry. A reduction of the diamond surface roughness was achieved by etching with manganese powder or cerium. (author)

Medical applications of diamond particles & surfaces

OpenAIRE

Roger J Narayan; Ryan D. Boehm; Anirudha V. Sumant

2011-01-01

Diamond has been considered for use in several medical applications due to its unique mechanical, chemical, optical, and biological properties. In this paper, methods for preparing synthetic diamond surfaces and particles are described. In addition, recent developments involving the use of diamond in prostheses, sensing, imaging, and drug delivery applications are reviewed. These developments suggest that diamond-containing structures will provide significant improvements in the diagnosis and...

Diamond Sensors for Energy Frontier Experiments

CERN Document Server

Schnetzer, Steve

2014-01-01

We discuss the use of diamond sensors in high-energy, high-i ntensity collider experiments. Re- sults from diamond sensor based beam conditions monitors in the ATLAS and CMS experiments at the CERN Large Hadron Collider (LHC) are presented and pla ns for diamond based luminosity monitors for the upcoming LHC run are described. We describe recent measurements on single crystal diamond sensors that indicate a polarization effec t that causes a reduction of charge col- lection efficiency as a function of particle flux. We conclude by describing new developments on the promising technology of 3D diamond sensors.

Genetics Home Reference: Diamond-Blackfan anemia

Science.gov (United States)

... Home Health Conditions Diamond-Blackfan anemia Diamond-Blackfan anemia Printable PDF Open All Close All Enable Javascript ... view the expand/collapse boxes. Description Diamond-Blackfan anemia is a disorder of the bone marrow . The ...

Diamond network: template-free fabrication and properties.

Science.gov (United States)

Zhuang, Hao; Yang, Nianjun; Fu, Haiyuan; Zhang, Lei; Wang, Chun; Huang, Nan; Jiang, Xin

2015-03-11

A porous diamond network with three-dimensionally interconnected pores is of technical importance but difficult to be produced. In this contribution, we demonstrate a simple, controllable, and "template-free" approach to fabricate diamond networks. It combines the deposition of diamond/β-SiC nanocomposite film with a wet-chemical selective etching of the β-SiC phase. The porosity of these networks was tuned from 15 to 68%, determined by the ratio of the β-SiC phase in the composite films. The electrochemical working potential and the reactivity of redox probes on the diamond networks are similar to those of a flat nanocrystalline diamond film, while their surface areas are hundreds of times larger than that of a flat diamond film (e.g., 490-fold enhancement for a 3 μm thick diamond network). The marriage of the unprecedented physical/chemical features of diamond with inherent advantages of the porous structure makes the diamond network a potential candidate for various applications such as water treatment, energy conversion (batteries or fuel cells), and storage (capacitors), as well as electrochemical and biochemical sensing.

Undoped CVD diamond films for electrochemical applications

International Nuclear Information System (INIS)

Mosinska, Lidia; Fabisiak, Kazimierz; Paprocki, Kazimierz; Kowalska, Magdalena; Popielarski, Pawel; Szybowicz, Miroslaw

2013-01-01

By using different deposition conditions, the CVD diamond films with different qualities and orientation were grown by the hot-filament CVD technique. The object of this article is to summarize and discuss relation between structural, physical and electrochemical properties of different diamond electrodes. The physical properties of the Hot Filament CVD microcrystalline diamond films are analyzed by scanning electron microscopy and Raman spectroscopy. In presented studies two different electrodes were used of the diamond grain sizes around 200 nm and 10 μm, as it was estimated from SEM picture. The diamond layers quality was checked on basis of FWHM (Full width at Half Maximum) of 1332 cm −1 diamond Raman peak. The ratio of sp 3 /sp 2 carbon bonds was determined by 1550 cm −1 G band and 1350 cm −1 D band in the Raman spectrum. The electrochemical properties were analyzed using (CV) cyclic voltammetry measurements in aqueous solutions. The sensitivity of undoped diamond electrodes depends strongly on diamond film quality and concentration of amorphous carbon phase in the diamond layer

Thin diamond films for tribological applications

International Nuclear Information System (INIS)

Wong, M.S.; Meilunas, R.; Ong, T.P.; Chang, R.P.H.

1989-01-01

Diamond films have been deposited on Si, Mo and many other substrates by microwave and radio frequency plasma enhanced chemical vapor deposition. Although the adhesion between the diamond film and most of the metal substrates is poor due to residual thermal stress from the mismatch of thermal expansion coefficients, the authors have developed processes to promote the growth of uniform and continuous diamond films with enhanced adhesion to metal substrates for tribological applications. The tribological properties of these films are measured using a ring-on-block tribotester. The coefficients of friction of diamond films sliding against a 52100 steel ring under the same experimental conditions are found to be significantly different depending on the morphology, grain size and roughness of the diamond films. However, under all cases tested, it is found that for uniform and continuous diamond films with small grain size of 1-3 micrometers, the coefficient of friction of the diamond film sliding against a steel ring under lubrication of a jet of mineral oil is about 0.04

Transparent nanocrystalline diamond coatings and devices

Science.gov (United States)

Sumant, Anirudha V.; Khan, Adam

2017-08-22

A method for coating a substrate comprises producing a plasma ball using a microwave plasma source in the presence of a mixture of gases. The plasma ball has a diameter. The plasma ball is disposed at a first distance from the substrate and the substrate is maintained at a first temperature. The plasma ball is maintained at the first distance from the substrate, and a diamond coating is deposited on the substrate. The diamond coating has a thickness. Furthermore, the diamond coating has an optical transparency of greater than about 80%. The diamond coating can include nanocrystalline diamond. The microwave plasma source can have a frequency of about 915 MHz.

Nanocrystalline diamond films for biomedical applications

DEFF Research Database (Denmark)

Pennisi, Cristian Pablo; Alcaide, Maria

2014-01-01

Nanocrystalline diamond films, which comprise the so called nanocrystalline diamond (NCD) and ultrananocrystalline diamond (UNCD), represent a class of biomaterials possessing outstanding mechanical, tribological, and electrical properties, which include high surface smoothness, high corrosion...... performance of nanocrystalline diamond films is reviewed from an application-specific perspective, covering topics such as enhancement of cellular adhesion, anti-fouling coatings, non-thrombogenic surfaces, micropatterning of cells and proteins, and immobilization of biomolecules for bioassays. In order...

Diamonds: Exploration, mines and marketing

Science.gov (United States)

Read, George H.; Janse, A. J. A. (Bram)

2009-11-01

The beauty, value and mystique of exceptional quality diamonds such as the 603 carat Lesotho Promise, recovered from the Letseng Mine in 2006, help to drive a multi-billion dollar diamond exploration, mining and marketing industry that operates in some 45 countries across the globe. Five countries, Botswana, Russia, Canada, South Africa and Angola account for 83% by value and 65% by weight of annual diamond production, which is mainly produced by four major companies, De Beers, Alrosa, Rio Tinto and BHP Billiton (BHPB), which together account for 78% by value and 72% by weight of annual diamond production for 2007. During the last twelve years 16 new diamond mines commenced production and 4 re-opened. In addition, 11 projects are in advanced evaluation and may begin operations within the next five years. Exploration for diamondiferous kimberlites was still energetic up to the last quarter of 2008 with most work carried out in Canada, Angola, Democratic Republic of the Congo (DRC) and Botswana. Many kimberlites were discovered but no new economic deposits were outlined as a result of this work, except for the discovery and possible development of the Bunder project by Rio Tinto in India. Exploration methods have benefitted greatly from improved techniques of high resolution geophysical aerial surveying, new research into the geochemistry of indicator minerals and further insights into the formation of diamonds and the relation to tectonic/structural events in the crust and mantle. Recent trends in diamond marketing indicate that prices for rough diamonds and polished goods were still rising up to the last quarter of 2008 and subsequently abruptly sank in line with the worldwide financial crisis. Most analysts predict that prices will rise again in the long term as the gap between supply and demand will widen because no new economic diamond discoveries have been made recently. The disparity between high rough and polished prices and low share prices of publicly

A new route to process diamond wires

Directory of Open Access Journals (Sweden)

Marcello Filgueira

2003-06-01

Full Text Available We propose an original route to process diamond wires, denominated In Situ Technology, whose fabrication involves mechanical conformation processes, such as rotary forging, copper tubes restacking, and thermal treatments, such as sintering and recrystallisation of a bronze 4 wt.% diamond composite. Tensile tests were performed, reaching an ultimate tensile strength (UTS of 230 MPa for the diameter of Æ = 1.84 mm. Scanning electron microscopy showed the diamond crystals distribution along the composite rope during its manufacture, as well as the diamond adhesion to the bronze matrix. Cutting tests were carried out with the processed wire, showing a probable performance 4 times higher than the diamond sawing discs, however its probable performance was about 5 to 8 times less than the conventional diamond wires (pearl system due to the low abrasion resistance of the bronze matrix, and low adhesion between the pair bronze-diamond due to the use of not metallised diamond single crystals.

The Geopolitical Setting of Conflict Diamonds.

Science.gov (United States)

Haggerty, S. E.

2002-05-01

September 11, 2001 will live in infamy. Ideological differences have also led to senseless atrocities in Angola, Congo Republic, Sierra Leone, and Liberia. Hundreds of thousands have died, scores mutilated, and millions displaced. These have gone virtually unnoticed for decades. Unnoticed that is until it became evident that these barbaric acts were fueled by the sale or bartering of diamonds for arms, or by more ingenious ways that are less traceable. There is no end in sight. Industry has long recognized that about 20% of diamonds reaching the open market are smuggled from operating mines, and more recently that an additional 4% originates from conflict diamond sources. Diamond identification by laser inscription, ion implantation, or certification protocols are subject to fraudulent tampering. And these applied methods are thwarted if cutting and polishing centers are infiltrated, or if terrorist facilities are independently established. Mark ups are substantial (40-60%) from raw material to finished product. Tracking the paths of rough stones from mines to faceted gems is impractical because some 30-50 million cts of top quality material, or about 100 million stones, would require branding each year. Moreover, the long standing tradition of site-holdings and the bourse system of mixing or matching diamonds, inadvertently ensures regional anonymity. Conflict diamonds are mined in primary kimberlites and from widely dispersed alluvial fields in tropical jungle. Landscapes, eroded by 1-5 vertical km over 100 Ma, have transformed low grade primary deposits into unconsolidated sedimentary bonanzas. The current value of stones retrieved, by motivated diggers and skillful jiggers, in rebel held territories, is impossible to determine, but in 1993 amounted to tens of millions USD. Diamonds over 100 cts continue to surface at premier prices. Borders are porous, diamonds flow easily, and armed networks are permeable and mobile. Diamonds form at great depths (over 200 km

R. S. Peters: The Reasonableness of Ethics

Science.gov (United States)

Haynes, Felicity

2013-01-01

This article will begin by examining the extent to which R. S. Peters merited the charge of analytic philosopher. His background in social psychology allowed him to become more pragmatic and grounded in social conventions and ordinary language than the analytic philosophers associated with empiricism, and his gradual shift from requiring internal…

CVD diamond windows for infrared synchrotron applications

International Nuclear Information System (INIS)

Sussmann, R.S.; Pickles, C.S.J.; Brandon, J.R.; Wort, C.J.H.; Coe, S.E.; Wasenczuk, A.; Dodge, C.N.; Beale, A.C.; Krehan, A.J.; Dore, P.; Nucara, A.; Calvani, P.

1998-01-01

This paper describes the attributes that make diamond a unique material for infrared synchrotron beam experiments. New developments in diamond synthesised by Chemical Vapour Deposition (CVD) promise to extend the range of applications which have been hitherto limited by the availability and cost of large-size single-crystal diamond. Polycrystalline CVD diamond components such as large (100 mm) diameter windows with extremely good transparency over a wide spectral range are now commercially available. Properties of CVD diamond of relevance to optical applications, such as mechanical strength, thermal conductivity and absolute bulk absorption, are discussed. It is shown that although some of the properties of CVD diamond (similar to other polycrystalline industrial ceramics) are affected by the grain structure, currently produced CVD diamond optical components have the quality and performance required for numerous demanding applications

Professor Peter Choyce: an early pioneer of intraocular lenses and corneal/refractive surgery.

Science.gov (United States)

Pandey, Suresh K; Apple, David J

2005-06-01

Professor Peter Choyce, FRCS, DOMS, MS, was one of the pioneers of intraocular lens implant surgery. He developed an interest in artificial lens implantation following cataract surgery, a procedure that was widely criticized by the ophthalmic establishment in the UK, Europe, North America and other countries. Owing to the opposition to the intraocular lenses, Peter Choyce together with Sir Harold Ridley co-founded the International Intraocular Implant Club in 1966, which was responsible for the gradual acceptance of artificial lens implantation. Peter Choyce developed several models of intraocular lens, but did not patent the majority of them. The Choyce Mark IX, manufactured by Rayner Intraocular Lenses, became the first US Food and Drug Administration-approved intraocular lens in 1981. A review of Peter Choyce's record confirms a significant number of original innovations in the field of anterior segment surgery, including many procedures taken for granted today, but not associated with his name. These include early work on both kerato- and intraocular lens-refractive procedures, keratoprosthesis, pioneering paediatric implant procedures and others. Unfortunately his tenacious adherence to anterior chamber lens technology, while in general clinically sound, caused many to question his influence and hence he remained poorly understood even until after his death. He passed away on 8 August 2001 after a long fight with colon cancer. In this article, we provide evidence and elaborate Peter Choyce's accomplishments, which places him as one of the most innovative ophthalmologist in his surgical field in the twentieth century.

Diamond Nucleation Using Polyethene

Science.gov (United States)

Morell, Gerardo (Inventor); Makarov, Vladimir (Inventor); Varshney, Deepak (Inventor); Weiner, Brad (Inventor)

2013-01-01

The invention presents a simple, non-destructive and non-abrasive method of diamond nucleation using polyethene. It particularly describes the nucleation of diamond on an electrically viable substrate surface using polyethene via chemical vapor deposition (CVD) technique in a gaseous environment.

Rootsi riigikaitsel uus siht / Peter Hultqvist ; intervjueeris Evelyn Kaldoja

Index Scriptorium Estoniae

Hultqvist, Peter

2017-01-01

Intervjuu Rootsi kaitseminister Peter Hultqvistiga Rootsi kaitsepoliitikast ja NATOsse astumise võimalusest. Läänemerel toimuvast Rootsi sõjalisest suurõppusest Aurora, kus osalevad ka Saaremaa kaitseliitlased ning miinijahtija Vambola

Diamond Growth in the Subduction Factory

Science.gov (United States)

Bureau, H.; Frost, D. J.; Bolfan-Casanova, N.; Leroy, C.; Estève, I.

2014-12-01

Natural diamonds are fabulous probes of the deep Earth Interior. They are the evidence of the deep storage of volatile elements, carbon at first, but also hydrogen and chlorine trapped as hydrous fluids in inclusions. The study of diamond growth processes in the lithosphere and mantle helps for our understanding of volatile elements cycling between deep reservoirs. We know now that inclusion-bearing diamonds similar to diamonds found in nature (i.e. polycrystalline, fibrous and coated diamonds) can grow in hydrous fluids or melts (Bureau et al., GCA 77, 202-214, 2012). Therefore, we propose that the best environment to promote such diamonds is the subduction factory, where highly hydrous fluids or melts are present. When oceanic plates are subducted in the lithosphere, they carry an oceanic crust soaked with seawater. While the slabs are traveling en route to the mantle, dehydration processes generate saline fluids highly concentrated in NaCl. In the present study we have experimentally shown that diamonds can grow from the saline fluids (up to 30 g/l NaCl in water) generated in subducted slabs. We have performed multi-anvil press experiments at 6-7 GPa and from 1300 to 1400°C during 6:00 hours to 30:00 hours. We observed large areas of new diamond grown in epitaxy on pure diamond seeds in salty hydrous carbonated melts, forming coated gems. The new rims are containing multi-component primary inclusions. Detailed characterizations of the diamonds and their inclusions have been performed and will be presented. These experimental results suggest that multi-component salty fluids of supercritical nature migrate with the slabs, down to the deep mantle. Such fluids may insure the first stage of the deep Earth's volatiles cycling (C, H, halogen elements) en route to the transition zone and the lower mantle. We suggest that the subduction factory may also be a diamond factory.

Peter Pan på All Inclusive

DEFF Research Database (Denmark)

Schwartz, Camilla

2017-01-01

I løbet af de sidste ti år er det blevet svært og ikke mindst enormt kedeligt at blive voksen i nyere dansk litteratur, og det i en sådan grad, at der måske i samtidslitteraturen er tale om en nærmst epidemisk modstand mod at blive formet og modnet i voksne termer. I artiklen Peter Pan på All...

Läbi legendide William Shakespeare'i poole / Maris Peters

Index Scriptorium Estoniae

Peters, Maris

2010-01-01

Tutvustus: Wells, Stanley. Kas on tõsi, et Shakespeare ...? / tõlkinud Maris Peters. Tallinn : Argo, 2010. Raamat William Shakespeare kohta käivatest legendidest, kuuldustest ja teooriatest ning tema teoste autorsusest

Reading R. S. Peters on Education Today

Science.gov (United States)

Cuypers, Stefaan E.; Martin, Christopher

2009-01-01

This introduction to this special issue offers an overview of R. S. Peters' seminal role in the development of modern philosophy of education, acknowledging the originality and range of his work, and indicating his continuing importance to the field. It explains the structure and organisation of the collection and provides a rationale for this…

Kaks teenetemärki Peter Hundile / Kalev Vilgats

Index Scriptorium Estoniae

Vilgats, Kalev

2010-01-01

Pärnu maavanem Andres Metsoja andis president Toomas Hendrik Ilvese volitusel AS Wendre suuromanikule Peter Hundile üle Valgetähe IV klassi teenetemärgi ettevõtluse edendamise eest. Ettevõtja pälvis ka Pärnu linna vapimärgi

Substitutional Boron in Nanodiamond, Bucky-Diamond, and Nanocrystalline Diamond Grain Boundaries

Energy Technology Data Exchange (ETDEWEB)

Barnard, Amanda S.; Sternberg, Michael G.

2006-10-05

Although boron has been known for many years to be a successful dopant in bulk diamond, efficient doping of nanocrystalline diamond with boron is still being developed. In general, the location, configuration, and bonding structure of boron in nanodiamond is still unknown, including the fundamental question of whether it is located within grains or grain boundaries of thin films and whether it is within the core or at the surface of nanoparticles. Presented here are density functional tight-binding simulations examining the configuration, potential energy surface, and electronic charge of substitutional boron in various types of nanocrystalline diamond. The results predict that boron is likely to be positioned at the surface of isolated particles and at the grain boundary of thin-film samples.

Ultimate Atomic Bling: Nanotechnology of Diamonds

Energy Technology Data Exchange (ETDEWEB)

Dahl, Jeremy

2010-05-25

Diamonds exist in all sizes, from the Hope Diamond to minuscule crystals only a few atoms across. The smallest of these diamonds are created naturally by the same processes that make petroleum. Recently, researchers discovered that these 'diamondoids' are formed in many different structural shapes, and that these shapes can be used like LEGO blocks for nanotechnology. This talk will discuss the discovery of these nano-size diamonds and highlight current SLAC/Stanford research into their applications in electronics and medicine.

Ultimate Atomic Bling: Nanotechnology of Diamonds

International Nuclear Information System (INIS)

Dahl, Jeremy

2010-01-01

Diamonds exist in all sizes, from the Hope Diamond to minuscule crystals only a few atoms across. The smallest of these diamonds are created naturally by the same processes that make petroleum. Recently, researchers discovered that these 'diamondoids' are formed in many different structural shapes, and that these shapes can be used like LEGO blocks for nanotechnology. This talk will discuss the discovery of these nano-size diamonds and highlight current SLAC/Stanford research into their applications in electronics and medicine.

Architecting boron nanostructure on the diamond particle surface

International Nuclear Information System (INIS)

Bai, H.; Dai, D.; Yu, J.H.; Nishimura, K.; Sasaoka, S.; Jiang, N.

2014-01-01

The present study provides an efficient approach for nano-functionalization of diamond powders. Boron nanostructure can be grown on diamond particle entire surface by a simple heat-treatment process. After treatment, various boron nanoforms were grown on the diamond particle surface at different processing temperature. High-density boron nanowires (BNWs) grow on the diamond particle entire surface at 1333 K, while nanopillars cover diamond powders when the heat treatment process is performed at 1393 K. The influence of the pretreatment temperature on the microstructure and thermal conductivity of Cu/diamond composites were investigated. Cu/diamond composites with high thermal conductivity of 670 W (m K) −1 was obtained, which was achieved by the formation of large number of nanowires and nanopillars on the diamond particle surface.

Cold cathodes on ultra-dispersed diamond base

International Nuclear Information System (INIS)

Alimova, A.N.; Zhirnov, V.V.; Chubun, N.N.; Belobrov, P.I.

1998-01-01

Prospects of application of nano diamond powders for fabrication of cold cathodes are discussed.Cold cathodes based on silicon pointed structures with nano diamond coatings were prepared.The deposition technique of diamond coating was dielectrophoresis from suspension of nano diamond powder in organic liquids.The cathodes were tested in sealed prototypes of vacuum electronic devices

Diamond growth in oxygen-acetylene flame

International Nuclear Information System (INIS)

Haga, Mario S.; Nagai, Y. Ernesto; Suzuki, Carlos K.

1995-01-01

What was supposed to be a laboratory curiosity in the 80's, in recent years the low pressure process for the production of man-made diamond turned out to be a major target for research and development of many high-tech companies. The main reason for such an interest stems on the possibility of coating many materials with a diamond film possessing the same amazing properties of the bulk natural diamond. Polycrystalline diamond film has been deposited on Mo substrate by using oxygen-acetylene flame of a welding torch. The substrate temperature has been held constant about 700 d eg C by means of a water cooled mount designed properly. Precision flowmeters have been used to control the flow ratio oxygen/acetylene, a key parameter for the success in diamond growth. Diamond has been detected by X-ray diffraction, a fast foolproof technique for crystal identification. Another method of analysis often used in Raman spectroscopy, which is able to exhibit amorphous structure besides crystalline phase. (author)

Copper-micrometer-sized diamond nanostructured composites

International Nuclear Information System (INIS)

Nunes, D; Livramento, V; Fernandes, H; Silva, C; Carvalho, P A; Shohoji, N; Correia, J B

2011-01-01

Reinforcement of a copper matrix with diamond enables tailoring the properties demanded for thermal management applications at high temperature, such as the ones required for heat sink materials in low activated nuclear fusion reactors. For an optimum compromise between thermal conductivity and mechanical properties, a novel approach based on multiscale diamond dispersions is proposed: a Cu-nanodiamond composite produced by milling is used as a nanostructured matrix for further dispersion of micrometer-sized diamond (μDiamond). A series of Cu-nanodiamond mixtures have been milled to establish a suitable nanodiamond fraction. A refined matrix with homogeneously dispersed nanoparticles was obtained with 4 at.% μDiamond for posterior mixture with microdiamond and subsequent consolidation. Preliminary consolidation by hot extrusion of a mixture of pure copper and μDiamond has been carried out to define optimal processing parameters. The materials produced were characterized by x-ray diffraction, scanning and transmission electron microscopy and microhardness measurements.

Development of CVD diamond radiation detectors

CERN Document Server

Adam, W; Berdermann, E; Bogani, F; Borchi, E; Bruzzi, Mara; Colledani, C; Conway, J; Dabrowski, W; Delpierre, P A; Deneuville, A; Dulinski, W; van Eijk, B; Fallou, A; Fisch, D; Foulon, F; Friedl, M; Gan, K K; Gheeraert, E; Grigoriev, E A; Hallewell, G D; Hall-Wilton, R; Han, S; Hartjes, F G; Hrubec, Josef; Husson, D; Kagan, H; Kania, D R; Kaplon, J; Kass, R; Knöpfle, K T; Krammer, Manfred; Manfredi, P F; Meier, D; Mishina, M; Le Normand, F; Pan, L S; Pernegger, H; Pernicka, Manfred; Pirollo, S; Re, V; Riester, J L; Roe, S; Roff, D G; Rudge, A; Schnetzer, S R; Sciortino, S; Speziali, V; Stelzer, H; Stone, R; Tapper, R J; Tesarek, R J; Thomson, G B; Trawick, M L; Trischuk, W; Turchetta, R; Walsh, A M; Wedenig, R; Weilhammer, Peter; Ziock, H J; Zoeller, M M

1998-01-01

Diamond is a nearly ideal material for detecting ionizing radiation. Its outstanding radiation hardness, fast charge collection and low leakage current allow a diamond detector to be used in high ra diation, high temperature and in aggressive chemical media. We have constructed charged particle detectors using high quality CVD diamond. Characterization of the diamond samples and various detect ors are presented in terms of collection distance, $d=\\mu E \\tau$, the average distance electron-hole pairs move apart under the influence of an electric field, where $\\mu$ is the sum of carrier mo bilities, $E$ is the applied electric field, and $\\tau$ is the mobility weighted carrier lifetime. Over the last two years the collection distance increased from $\\sim$ 75 $\\mu$m to over 200 $\\mu$ m. With this high quality CVD diamond a series of micro-strip and pixel particle detectors have been constructed. These devices were tested to determine their position resolution and signal to n oise performance. Diamond detectors w...

The Existential Concern of the Humanities R. S. Peters' Justification of Liberal Education

Science.gov (United States)

Cuypers, Stefaan E.

2018-01-01

Richard Stanley Peters was one of the founding fathers of analytic philosophy of education in the twentieth century. After reviewing Peters' disentanglement of the ambiguities of liberal education, I reconstruct his view on the status and the existential foundations of the humanities. What emerges from my reconstruction is an original…

The "Physically Educated" Person: Physical Education in the Philosophy of Reid, Peters and Aristotle

Science.gov (United States)

MacAllister, James

2013-01-01

This article will derive a definition and account of the physically educated person, through an examination of the philosophy of Andrew Reid, Richard Peters and Aristotle. Initially, Reid's interpretation of Peters' views about the educational significance of practical knowledge (and physical education) will be considered. While it will…

A new species of Temnocephala Blanchard (Platyhelminthes, Temnocephalida ectosymbiont on Trichodactylus fluviatilis Latreille (Crustacea, Decapoda, Trichodactylidae from southern Brazil Nova espécie de Temnocephala Blanchard ectosimbionte sobre Trichodactylus fluviatilis Latreille (Crustacea, Decapoda, Trichodactylidae da região Sul do Brasil

Directory of Open Access Journals (Sweden)

José F. R. Amato

2006-09-01

Full Text Available Temnocephala trapeziformis sp. nov., ectosymbiont on Trichodactylus fluviatilis Latreille, 1828 is described from the State of Rio Grande do Sul, southern Brazil. Sixty-eight crabs were examined, of which 61 (89.7 % were positive for this species of the genus Temnocephala Blanchard, 1849. Eggs, as well as adult and young specimens, were found on the pleural areas of the carapace, in the orbital cavities, and, usually, on the fourth pair of pereiopods. The temnocephalans were always devoid of body pigmentation, although they kept the red eye pigment, undiluted in specimens fixed by hot (90ºC phosphate buffered 10% formalin. The most distinctive characters of the new species are: 1 the shape and size of the cirrus and the characteristics of its introvert section; 2 the trapezoidal shape of the dorsolateral post-tentacular 'excretory' epidermal syncytial plates, with the nephridiopore in the lower inner corner of the plate; and 3 the number, size, and distribution of the rhabdite producing glands, as observed in very young specimens.Temnocephala trapeziformis sp. nov., ectosimbionte sobre Trichodactylus fluviatilis Latreille, 1828 é descrita para o Estado do Rio Grande do Sul, região sul do Brasil. Sessenta e oito caranguejos foram examinados, sendo que 61 (89,7 % estavam positivos para esta espécie do gênero Temnocephala Blanchard, 1849. Posturas estavam localizadas, sobre as pleuras da carapaça, nas cavidades orbitais e no quarto par de pereiópodos, locais onde também foram encontrados espécimes jovens e adultos. Os temnocefalídeos sempre se apresentaram sem pigmento corporal, embora o pigmento vermelho dos olhos tenha sido preservado nos espécimes fixados em formalina 10% fosfato tamponada (90ºC. Os caracteres mais distintos da nova espécie são: 1 a forma e o tamanho do cirro e as características do 'introvert', 2 as placas sinciciais 'excretoras' trapeziformes, com o nefridióporo sempre deslocado para o canto inferior interno de

Peter Jarvis and the Understanding of Adult Learning

Science.gov (United States)

Illeris, Knud

2017-01-01

By comparing Peter Jarvis' understanding of learning with two other approaches--which Jarvis himself has referred to as "the most comprehensive": Etienne Wenger's "social theory of learning" and my own psychologically oriented theory of "the three dimensions of learning"--it becomes evident that Jarvis' understanding…

X-ray topographic study of diamonds: implications for the genetic nature of inclusions in diamond

Science.gov (United States)

Agrosì, Giovanna; Nestola, Fabrizio; Tempesta, Gioacchino; Bruno, Marco; Scandale, Eugenio; Harris, Jeff W.

2014-05-01

In recent years, several studies have focused on the growth conditions of the diamonds through the analysis of the mineral inclusions trapped in them (Howell, 2012 and references therein). Nevertheless, to obtain rigorous information about chemical and physical conditions of diamond formation, it is crucial to determine if the crystallization of the inclusions occurred before (protogenetic nature), during (syngenetic nature) or after (epigenetic nature) the growth of diamond (Wiggers de Vries et al., 2011). X-ray topography (XRDT) can be a helpful tool to verify the genetic nature of inclusions in diamond. This technique characterizes the extended defects and reconstructs the growth history of the samples (Agrosì et al., 2013 and references therein) and, consequently contributes to elucidation of the relationship between the inclusions and the host-diamond. With this aim a diamond from the Udachnaya kimberlite, Siberia, was investigated. The diamond crystal was the one previously studied by Nestola et al. (2011) who performed in-situ crystal structure refinement of the inclusions to obtain data about the formation pressure. The inclusions were iso-oriented olivines that did not show evident cracks and subsequently could not be considered epigenetic. Optical observations revealed an anomalous birefringence in the adjacent diamond and the inclusions had typical "diamond-imposed cubo-octahedral" shape for the largest olivine. The diffraction contrast study shows that the diamond exhibits significant deformation fields related to plastic post growth deformation. The crystallographic direction of strains was established applying the extinction criterion. Section topographs were taken to minimize the overlapping of the strain field associate with the different defects and revealed that no dislocations nucleated from the olivine inclusions. Generally, when a solid inclusion has been incorporated in the growing crystal, the associated volume distortion can be minimized by

Diamond nanowires: fabrication, structure, properties, and applications.

Science.gov (United States)

Yu, Yuan; Wu, Liangzhuan; Zhi, Jinfang

2014-12-22

C(sp(3) )C-bonded diamond nanowires are wide band gap semiconductors that exhibit a combination of superior properties such as negative electron affinity, chemical inertness, high Young's modulus, the highest hardness, and room-temperature thermal conductivity. The creation of 1D diamond nanowires with their giant surface-to-volume ratio enhancements makes it possible to control and enhance the fundamental properties of diamond. Although theoretical comparisons with carbon nanotubes have shown that diamond nanowires are energetically and mechanically viable structures, reproducibly synthesizing the crystalline diamond nanowires has remained challenging. We present a comprehensive, up-to-date review of diamond nanowires, including a discussion of their synthesis along with their structures, properties, and applications. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Performance and characterisation of CVD diamond coated, sintered diamond and WC-Co cutting tools for dental and micromachining applications

International Nuclear Information System (INIS)

Sein, Htet; Ahmed, Waqar; Jackson, Mark; Woodwards, Robert; Polini, Riccardo

2004-01-01

Diamond coatings are attractive for cutting processes due to their high hardness, low friction coefficient, excellent wear resistance and chemical inertness. The application of diamond coatings on cemented tungsten carbide (WC-Co) tools was the subject of much attention in recent years in order to improve cutting performance and tool life. WC-Co tools containing 6% Co and 94% WC substrate with an average grain size 1-3 μm were used in this study. In order to improve the adhesion between diamond and WC substrates, it is necessary to etch away the surface Co and prepare the surface for subsequent diamond growth. Hot filament chemical vapour deposition with a modified vertical filament arrangement has been employed for the deposition of diamond films. Diamond film quality and purity have been characterised using scanning electron microscopy and micro-Raman spectroscopy. The performance of diamond coated WC-Co bur, uncoated WC-Co bur, and diamond embedded (sintered) bur have been compared by drilling a series of holes into various materials such as human teeth, borosilicate glass and porcelain teeth. Flank wear has been used to assess the wear rates of the tools. The materials subjected to cutting processes have been examined to assess the quality of the finish. Diamond coated WC-Co microdrills and uncoated microdrills were also tested on aluminium alloys. Results show that there was a 300% improvement when the drills were coated with diamond compared to the uncoated tools

STRUCTURING OF DIAMOND FILMS USING MICROSPHERE LITHOGRAPHY

Directory of Open Access Journals (Sweden)

Mária Domonkos

2014-10-01

Full Text Available In this study, the structuring of micro- and nanocrystalline diamond thin films is demonstrated. The structuring of the diamond films is performed using the technique of microsphere lithography followed by reactive ion etching. Specifically, this paper presents a four-step fabrication process: diamond deposition (microwave plasma assisted chemical vapor deposition, mask preparation (by the standard Langmuir-Blodgett method, mask modification and diamond etching. A self-assembled monolayer of monodisperse polystyrene (PS microspheres with close-packed ordering is used as the primary template. Then the PS microspheres and the diamond films are processed in capacitively coupled radiofrequency plasma  using different plasma chemistries. This fabrication method illustrates the preparation of large arrays of periodic and homogeneous hillock-like structures. The surface morphology of processed diamond films is characterized by scanning electron microscopy and atomic force microscope. The potential applications of such diamond structures in various fields of nanotechnology are also briefly discussed.

Note: Evaluation of microfracture strength of diamond materials using nano-polycrystalline diamond spherical indenter

Science.gov (United States)

Sumiya, H.; Hamaki, K.; Harano, K.

2018-05-01

Ultra-hard and high-strength spherical indenters with high precision and sphericity were successfully prepared from nanopolycrystalline diamond (NPD) synthesized by direct conversion sintering from graphite under high pressure and high temperature. It was shown that highly accurate and stable microfracture strength tests can be performed on various super-hard diamond materials by using the NPD spherical indenters. It was also verified that this technique enables quantitative evaluation of the strength characteristics of single crystal diamonds and NPDs which have been quite difficult to evaluate.

Hans-Peter Schultze, a great paleoichthyologist for whom work is synonymous with enjoyment

Directory of Open Access Journals (Sweden)

R. Cloutier

2002-01-01

Full Text Available In the summer of 1982, Hans-Peter Schultze and Gloria Arratia were invited to a small museum located on a fossiliferous site of the Devonian Escuminac Formation in Miguasha, Quebec, eastern Canada, Hans-Peter was to work with Marius Arsenault, the director of the Miguasha Museum, on the skull of the elpistostegalid Elpistostege watsoni, a species closely related to basal tetrapod. In addition, he went through the collections to describe and measure numerous juvenile specimens of the osteolepiform. Eusthenopteran foordi. As expected, there two projects turned out to be important contributions in lower vertebrate paleontology and systematics: one on the origin of tetrapods (1985, and the second one on growth patterns of a Late Devonian fish (1984. During his visit to Miguasha, Hans-Peter also spent time digging for fossils and drawing numerous specimens in the collection. In addition, in order to help the personnel of the museum to identify some of the Escuminac fished, he created an identification key based on the gross morphology of the scales. For a small group of undergraduate students, hired at the museum during the summer as naturalists, it was a unique opportunity to discuss paleontology with a leading researcher. We were amazed by his willingness to talk to us, even if then most of us only spoke French! For the first time, we were exposed to Hennigian methodology and its usage in vertebrate paleontology during and evening lecture that Hans-Peter prepared for us. His lecture was delightful; it was an intensive course in lower vertebrate anatomy, and an intellectual journey among the philosophers Karl Marx and Karl Popper, the entomologists Willy Hennig and Lars Brundin, and "The Band of Four" (Rosen et al., 1981. It was for most of us our first exposure to science, as it should be done. We were all impressed by his knowledge and above all by his simplicity and friendliness. Two years later I started my Ph.D. at The University of Kansas

Diamond detector technology: status and perspectives

CERN Document Server

Kagan, Harris; Artuso, M; Bachmair, F; Bäni, L; Bartosik, M; Beacham, J; Beck, H P; Bellini,, V; Belyaev, V; Bentele, B; Berdermann, E; Bergonzo, P; Bes, A; Brom, J-M; Bruzzi, M; Cerv, M; Chiodini, G; Chren, D; Cindro, V; Claus, G; Collot, J; Cumalat, J; Dabrowski, A; D'Alessandro, R; De Boer, W; Dehning, B; Dorfer, C; Dunser, M; Eremin, V; Eusebi, R; Forcolin, G; Forneris, J; Frais-Kölbl, H; Gan, K K; Gastal, M; Giroletti, C; Goffe, M; Goldstein, J; Golubev, A; Gorišek, A; Grigoriev, E; Grosse-Knetter, J; Grummer, A; Gui, B; Guthoff, M; Haughton, I; Hiti, B; Hits, D; Hoeferkamp, M; Hofmann, T; Hosslet, J; Hostachy, J-Y; Hügging, F; Hutton, C; Jansen, H; Janssen, J; Kanxheri, K; Kasieczka, G; Kass, R; Kassel, F; Kis, M; Kramberger, G; Kuleshov, S; Lacoste, A; Lagomarsino, S; Lo Giudice, A; Lukosi, E; Maazouzi, C; Mandic, I; Mathieu, C; Mcfadden, N; Menichelli, M; Mikuž, M; Morozzi, A; Moss, J; Mountain, R; Murphy, S; Muškinja, M; Oh, A; Oliviero, P; Passeri, D; Pernegger, H; Perrino, R; Picollo, F; Pomorski, M; Potenza, R; Quadt, A; Re, A; Reichmann, M; Riley, G; Roe, S; Sanz, D; Scaringella, M; Schaefer, D; Schmidt, C J; Schnetzer, S; Schreiner, T; Sciortino, S; Scorzoni, A; Seidel, S; Servoli, L; Sopko, B; Sopko, V; Spagnolo, S; Spanier, S; Stenson, K; Stone, R; Sutera, C; Taylor, Aaron; Traeger, M; Tromson, D; Trischuk, W; Tuve, C; Uplegger, L; Velthuis, J; Venturi, N; Vittone, E; Wagner, Stephen; Wallny, R; Wang, J C; Weingarten, J; Weiss, C; Wengler, T; Wermes, N; Yamouni, M; Zavrtanik, M

2017-01-01

The status of material development of poly-crystalline chemical vapor deposition (CVD) diamond is presented. We also present beam test results on the independence of signal size on incident par-ticle rate in charged particle detectors based on un-irradiated and irradiated poly-crystalline CVD diamond over a range of particle fluxes from 2 kHz/cm2 to 10 MHz/cm2. The pulse height of the sensors was measured with readout electronics with a peaking time of 6 ns. In addition the first beam test results from 3D detectors made with poly-crystalline CVD diamond are presented. Finally the first analysis of LHC data from the ATLAS Diamond Beam Monitor (DBM) which is based on pixelated poly-crystalline CVD diamond sensors bump-bonded to pixel readout elec-tronics is shown.

Diamond electrophoretic microchips-Joule heating effects

International Nuclear Information System (INIS)

Karczemska, Anna T.; Witkowski, Dariusz; Ralchenko, Victor; Bolshakov, Andrey; Sovyk, Dmitry; Lysko, Jan M.; Fijalkowski, Mateusz; Bodzenta, Jerzy; Hassard, John

2011-01-01

Microchip electrophoresis (MCE) has become a mature separation technique in the recent years. In the presented research, a polycrystalline diamond electrophoretic microchip was manufactured with a microwave plasma chemical vapour deposition (MPCVD) method. A replica technique (mould method) was used to manufacture microstructures in diamond. A numerical analysis with CoventorWare TM was used to compare thermal properties during chip electrophoresis of diamond and glass microchips of the same geometries. Temperature distributions in microchips were demonstrated. Thermal, electrical, optical, chemical and mechanical parameters of the polycrystalline diamond layers are advantageous over traditionally used materials for microfluidic devices. Especially, a very high thermal conductivity coefficient gives a possibility of very efficient dissipation of Joule heat from the diamond electrophoretic microchip. This enables manufacturing of a new generation of microdevices.

Diamond electrophoretic microchips-Joule heating effects

Energy Technology Data Exchange (ETDEWEB)

Karczemska, Anna T., E-mail: anna.karczemska@p.lodz.pl [Technical University of Lodz, Institute of Turbomachinery, 219/223 Wolczanska str., Lodz (Poland); Witkowski, Dariusz [Technical University of Lodz, Institute of Turbomachinery, 219/223 Wolczanska str., Lodz (Poland); Ralchenko, Victor, E-mail: ralchenko@nsc.gpi.ru [General Physics Institute, Russian Academy of Science, 38 Vavilov str., Moscow (Russian Federation); Bolshakov, Andrey; Sovyk, Dmitry [General Physics Institute, Russian Academy of Science, 38 Vavilov str., Moscow (Russian Federation); Lysko, Jan M., E-mail: jmlysko@ite.waw.pl [Institute of Electron Technology, Al. Lotnikow 32/46, 02-668 Warsaw (Poland); Fijalkowski, Mateusz, E-mail: petr.louda@vslib.cz [Technical University of Liberec, Faculty of Mechanical Engineering (Czech Republic); Bodzenta, Jerzy, E-mail: jerzy.bodzenta@polsl.pl [Silesian University of Technology, Institute of Physics, 2 Krzywoustego str., 44-100 Gliwice (Poland); Hassard, John, E-mail: j.hassard@imperial.ac.uk [Imperial College of Science, Technology and Medicine, London (United Kingdom)

2011-03-15

Microchip electrophoresis (MCE) has become a mature separation technique in the recent years. In the presented research, a polycrystalline diamond electrophoretic microchip was manufactured with a microwave plasma chemical vapour deposition (MPCVD) method. A replica technique (mould method) was used to manufacture microstructures in diamond. A numerical analysis with CoventorWare{sup TM} was used to compare thermal properties during chip electrophoresis of diamond and glass microchips of the same geometries. Temperature distributions in microchips were demonstrated. Thermal, electrical, optical, chemical and mechanical parameters of the polycrystalline diamond layers are advantageous over traditionally used materials for microfluidic devices. Especially, a very high thermal conductivity coefficient gives a possibility of very efficient dissipation of Joule heat from the diamond electrophoretic microchip. This enables manufacturing of a new generation of microdevices.

Kunsti lastekodu / Stuart Bailey, Peter Bilak ; intervjueerinud Kristjan Mändmaa

Index Scriptorium Estoniae

Bailey, Stuart

2011-01-01

Rahvusvahelisest disainiajakirjast Dot Dot Dot. Väljaandjate slovakkia disaineri ja tüpograafi Peter Bilaki ja inglise disaineri Stuart Bailey eluloolisi andmeid. Korraldavad õpikoja Eesti Kunstiakadeemias

Ohmic contacts to semiconducting diamond

Science.gov (United States)

Zeidler, James R.; Taylor, M. J.; Zeisse, Carl R.; Hewett, C. A.; Delahoussaye, Paul R.

1990-10-01

Work was carried out to improve the electron beam evaporation system in order to achieve better deposited films. The basic system is an ion pumped vacuum chamber, with a three-hearth, single-gun e-beam evaporator. Four improvements were made to the system. The system was thoroughly cleaned and new ion pump elements, an e-gun beam adjust unit, and a more accurate crystal monitor were installed. The system now has a base pressure of 3 X 10(exp -9) Torr, and can easily deposit high-melting-temperature metals such as Ta with an accurately controlled thickness. Improved shadow masks were also fabricated for better alignment and control of corner contacts for electrical transport measurements. Appendices include: A Thermally Activated Solid State Reaction Process for Fabricating Ohmic Contacts to Semiconducting Diamond; Tantalum Ohmic Contacts to Diamond by a Solid State Reaction Process; Metallization of Semiconducting Diamond: Mo, Mo/Au, and Mo/Ni/Au; Specific Contact Resistance Measurements of Ohmic Contracts to Diamond; and Electrical Activation of Boron Implanted into Diamond.

Diamond-Based Supercapacitors: Realization and Properties.

Science.gov (United States)

Gao, Fang; Nebel, Christoph E

2016-10-26

In this Spotlight on Applications, we describe our recent progress on the fabrication of surface-enlarged boron-doped polycrystalline diamond electrodes, and evaluate their performance in supercapacitor applications. We begin with a discussion of the fabrication methods of porous diamond materials. The diamond surface enlargement starts with a top-down plasma etching method. Although the extra surface area provided by surface roughening or nanostructuring provides good outcome for sensing applications, a capacitance value <1 mF cm -2 or a surface-enlargement factor <100 fail to meet the requirement of a practical supercapacitor. Driven by the need for large surface areas, we recently focused on the tempated-growth method. We worked on both supported and free-standing porous diamond materials to enhance the areal capacitance to the "mF cm -2 " range. With our newly developed free-standing diamond paper, areal capacitance can be multiplied by stacking multilayers of the electrode material. Finally, considering the fact that there is no real diamond-based supercapacitor device up to now, we fabricated the first prototype pouch-cell device based on the free-standing diamond paper to evaluate its performance. The results reveal that the diamond paper is suitable for operation in high potential windows (up to 2.5 V) in aqueous electrolyte with a capacitance of 0.688 mF cm -2 per layer of paper (or 0.645 F g -1 ). Impedance spectroscopy revealed that the operation frequency of the device exceeds 30 Hz. Because of the large potential window and the ability to work at high frequency, the specific power of the device reached 1 × 10 5 W kg -1 . In the end, we made estimations on the future target performance of diamond supercapacitors based on the existing information.

Modifying thin film diamond for electronic applications

International Nuclear Information System (INIS)

Baral, B.

1999-01-01

The unique combination of properties that diamond possesses are being exploited in both electronic and mechanical applications. An important step forward in the field has been the ability to grow thin film diamond by chemical vapour deposition (CVD) methods and to control parameters such as crystal orientation, dopant level and surface roughness. An extensive understanding of the surface of any potential electronic material is vital to fully comprehend its behaviour within device structures. The surface itself ultimately controls key aspects of device performance when interfaced with other materials. This study has provided insight into important chemical reactions on polycrystalline CVD diamond surfaces, addressing how certain surface modifications will ultimately affect the properties of the material. A review of the structure, bonding, properties and potential of diamond along with an account of the current state of diamond technology and CVD diamond growth is provided. The experimental chapter reviews bulk material and surface analytical techniques employed in this work and is followed by an investigation of cleaning treatments for polycrystalline CVD diamond aimed at removing non-diamond carbon from the surface. Selective acid etch treatments are compared and contrasted for efficacy with excimer laser irradiation and hydrogen plasma etching. The adsorption/desorption kinetics of potential dopant-containing precursors on polycrystalline CVD diamond surfaces have been investigated to compare their effectiveness at introducing dopants into the diamond during the growth stage. Both boron and sulphur-containing precursor compounds have been investigated. Treating polycrystalline CVD diamond in various atmospheres / combination of atmospheres has been performed to enhance electron field emission from the films. Films which do not emit electrons under low field conditions can be modified such that they emit at fields as low as 10 V/μm. The origin of this enhancement

UV detectors based on epitaxial diamond films grown on single-crystal diamond substrates by vapor-phase synthesis

International Nuclear Information System (INIS)

Sharonov, G.V.; Petrov, S.A.; Bol'shakov, A.P.; Ral'chenko, V.G.; Kazyuchits, N.M.

2010-01-01

The prospects for use of CVD-technology for epitaxial growth of single-crystal diamond films of instrumental quality in UHF plasma for the production of optoelectronic devices are discussed. A technology for processing diamond single crystals that provides a perfect surface crystal structure with roughness less than 0,5 nm was developed. It was demonstrated that selective UV detectors based on synthetic single-crystal diamond substrates coated with single-crystal films can be produced. A criterion for selecting clean and structurally perfect single crystals of synthetic diamond was developed for the epitaxial growth technology. (authors)

Recent results on CVD diamond radiation sensors

Science.gov (United States)

Weilhammer, P.; Adam, W.; Bauer, C.; Berdermann, E.; Bogani, F.; Borchi, E.; Bruzzi, M.; Colledani, C.; Conway, J.; Dabrowski, W.; Delpierre, P.; Deneuville, A.; Dulinski, W.; v. d. Eijk, R.; van Eijk, B.; Fallou, A.; Fish, D.; Fried, M.; Gan, K. K.; Gheeraert, E.; Grigoriev, E.; Hallewell, G.; Hall-Wilton, R.; Han, S.; Hartjes, F.; Hrubec, J.; Husson, D.; Kagan, H.; Kania, D.; Kaplon, J.; Kass, R.; Knopfle, K. T.; Krammer, M.; Manfredi, P. F.; Meier, D.; LeNormand; Pan, L. S.; Pernegger, H.; Pernicka, M.; Plano, R.; Re, V.; Riester, J. L.; Roe, S.; Roff; Rudge, A.; Schieber, M.; Schnetzer, S.; Sciortino, S.; Speziali, V.; Stelzer, H.; Stone, R.; Tapper, R. J.; Tesarek, R.; Thomson, G. B.; Trawick, M.; Trischuk, W.; Turchetta, R.; RD 42 Collaboration

1998-02-01

CVD diamond radiation sensors are being developed for possible use in trackers in the LHC experiments. The diamond promises to be radiation hard well beyond particle fluences that can be tolerated by Si sensors. Recent results from the RD 42 collaboration on charge collection distance and on radiation hardness of CVD diamond samples will be reported. Measurements with diamond tracking devices, both strip detectors and pixel detectors, will be discussed. Results from beam tests using a diamond strip detector which was read out with fast, 25 ns shaping time, radiation-hard pipeline electronics will be presented.

CVD diamond deposition onto dental burs

International Nuclear Information System (INIS)

Ali, N.; Sein, H.

2001-01-01

A hot-filament chemical vapor deposition (HFCVD) system has been modified to enable non-planar substrates, such as metallic wires and dental burs, to be uniformly coated with thin polycrystalline diamond films. Initially, diamond deposition was carried out on titanium and tantalum wires in order to test and optimize the system. High growth rates of the order of approx. 8 /hr were obtained when depositing diamond on titanium wires using the vertical filament arrangement. However, lower growth rates of the order of 4-5meu m/hr were obtained with diamond deposition on tantalum wires. To extend the work towards a practical biomedical application tungsten carbide dental burs were coated with diamond films. The as-grown films were found to be polycrystalline and uniform over the cutting tip. Finally, the costs relating to diamond CVD onto dental burs have been presented in this paper. The costs relating to coating different number of burs at a time and the effect of film thickness on costs have been included in this investigation. (author)

Panel 2 - properties of diamond and diamond-like-carbon films

Energy Technology Data Exchange (ETDEWEB)

Blau, P.J.; Clausing, R.E. [Oak Ridge National Lab., TN (United States); Ajayi, O.O.; Liu, Y.Y.; Purohit, A. [Argonne National Lab., IL (United States); Bartelt, P.F. [Deere & Co., Moline, IL (United States); Baughman, R.H. [Allied Signal, Morristown, NJ (United States); Bhushan, B. [Ohio State Univ., Columbus (United States); Cooper, C.V. [United Technologies Research Center, East Hartford, CT (United States); Dugger, M.T. [Sandia National Laboratories, Albuquerque, NM (United States); Freedman, A. [Aerodyne Research, Inc., Billerica, MA (United States); Larsen-Basse, J. [National Science Foundation, Washington, DC (United States); McGuire, N.R. [Caterpillar, Peoria, IL (United States); Messier, R.F. [Pennsylvania State Univ., University Park (United States); Noble, G.L.; Ostrowki, M.H. [John Crane, Inc., Morton Grove, IL (United States); Sartwell, B.D. [Naval Research Lab., Washington, DC (United States); Wei, R. [Colorado State Univ., Fort Collins (United States)

1993-01-01

This panel attempted to identify and prioritize research and development needs in determining the physical, mechanical and chemical properties of diamond and diamond-like-carbon films (D/DLCF). Three specific goals were established. They were: (1) To identify problem areas which produce concern and require a better knowledge of D/DLCF properties. (2) To identify and prioritize key properties of D/DLCF to promote transportation applications. (3) To identify needs for improvement in properties-measurement methods. Each of these goals is addressed subsequently.

Drilling of optical glass with electroplated diamond tools

Science.gov (United States)

Wang, A. J.; Luan, C. G.; Yu, A. B.

2010-10-01

K9 optical glass drilling experiments were carried out. Bright nickel electroplated diamond tools with small slots and under heat treatment in different temperature were fabricated. Scan electro microscope was applied to analyze the wear of electroplated diamond tool. The material removal rate and grinding ratio were calculated. Machining quality was observed. Bond coating hardness was measured. The experimental results show that coolant is needed for the drilling processes of optical glasses. Heat treatment temperature of diamond tool has influence on wearability of diamond tool and grinding ratio. There were two wear types of electroplated diamond tool, diamond grit wear and bond wear. With the machining processes, wear of diamond grits included fracture, blunt and pull-out, and electroplated bond was gradually worn out. High material removal rates could be obtained by using diamond tool with suitable slot numbers. Bright nickel coating bond presents smallest grains and has better mechanical properties. Bright nickel electroplated diamond tool with slot structure and heat treatment under 200°C was suitable for optical glass drilling.

The Statue of Liberty Peter Max Style!

Science.gov (United States)

Cunningham, Kathy

2012-01-01

The author's school is only 30 minutes from New York City, so every year when second-graders study towns and cities, the students do a project based on New York City landmarks. This year was the Statue of Liberty. The author introduced Peter Max's famous Pop art to her students, and explained that, as the art world kept changing, artists decided…

Modeling of diamond radiation detectors

International Nuclear Information System (INIS)

Milazzo, L.; Mainwood, A.

2004-01-01

We have built up a computer simulation of the detection mechanism in the diamond radiation detectors. The diamond detectors can be fabricated from a chemical vapour deposition polycrystalline diamond film. In this case, the trapping-detrapping and recombination at the defects inside the grains and at the grain boundaries degrade the transport properties of the material and the charge induction processes. These effects may strongly influence the device's response. Previous simulations of this kind of phenomena in the diamond detectors have generally been restricted to the simple detector geometries and homogeneous distribution of the defects. In our model, the diamond film (diamond detector) is simulated by a grid. We apply a spatial and time discretization, regulated by the grid resolution, to the equations describing the charge transport and, by using the Shockley-Ramo theorem, we calculate the signal induced on the electrodes. In this way, we can simulate the effects of the nonhomogeneous distributions of the trapping, recombination, or scattering centers and can investigate the differences observed when different particles, energies, and electrode configurations are used. The simulation shows that the efficiency of the detector increases linearly with the average grain size, that the charge collection distance is small compared to the dimensions of a single grain, and that for small grains, the trapping at the intragrain defects is insignificant compared to the effect of the grain boundaries

Towards an amphibious anthropology: water and Peter Sloterdijk

NARCIS (Netherlands)

Bos, R. ten

2009-01-01

In the paper Peter Sloterdijk is portrayed as a philosopher of elements who tries to correct the traditional philosophical reliance on earth by focusing on the elements air and water. The paper discusses the role that the latter element plays in Sloterdijk's philosophy. It is argued that it is

Unfreiwillige Wanderschaft im Erzählwerk Peter Härtlings

Czech Academy of Sciences Publication Activity Database

Ulbrecht, Siegfried

2012-01-01

Roč. 23, č. 2 (2012), s. 108-128 ISSN 1210-9029 Institutional support: RVO:68378017 Keywords : Härtling, Peter * literary studies * autobiographical prose * contemporary German literature * escape and displacement Subject RIV: AJ - Letters, Mass-media, Audiovision

D.C. Arcjet Diamond Deposition

Science.gov (United States)

Russell, Derrek Andrew

1995-01-01

Polycrystalline diamond films synthesized by a D.C. (direct current) arcjet device was reported for the first time in 1988. This device is capable of higher diamond growth rates than any other form of diamond CVD (chemical vapor deposition) process due to its inherent versatility with regard to the enthalpy and fluid properties of the diamond-depositing vapor. Unfortunately, the versatility of this type of device is contrasted by many difficulties such as arc stability and large heat fluxes which make applying it toward diamond deposition a difficult problem. The purpose of this work was to convert the dc arcjet, which is primarily a metallurgical device, into a commercially viable diamond CVD process. The project was divided into two parts: process development and diagnostics. The process development effort concentrated on the certain engineering challenges. Among these was a novel arcjet design that allowed the carbon-source gas to be injected downstream of the tungsten cathode while still facilitating mixture with the main gas feed. Another engineering accomplishment was the incorporation of a water -cooled substrate cooler/spinner that maintained the substrate at the proper temperature, provided the substrate with a large thermal time constant to reduce thermal shock of the diamond film, and enabled the system to achieve a four -inch diameter growth area. The process diagnostics effort concentrated on measurements aimed at developing a fundamental understanding of the properties of the plasma jet such as temperature, plasma density, Mach number, pressure at the substrate, etc. The plasma temperature was determined to be 5195 K by measuring the rotational temperature of C _2 via optical emission spectroscopy. The Mach number of the plasma jet was determined to be ~6.0 as determined by the ratio of the stagnation pressures before and after the shock wave in the plasma jet. The C_2 concentration in the plasma jet was determined to be {~10 }^{12} cm^ {-3} by

Diamond films: Historical perspective

Energy Technology Data Exchange (ETDEWEB)

Messier, R. [Pennsylvania State Univ., University Park (United States)

1993-01-01

This section is a compilation of notes and published international articles about the development of methods of depositing diamond films. Vapor deposition articles are included from American, Russian, and Japanese publications. The international competition to develop new deposition methodologies is stressed. The current status of chemical vapor deposition of diamond is assessed.

Comparison of natural and synthetic diamond X-ray detectors.

Science.gov (United States)

Lansley, S P; Betzel, G T; Metcalfe, P; Reinisch, L; Meyer, J

2010-12-01

Diamond detectors are particularly well suited for dosimetry applications in radiotherapy for reasons including near-tissue equivalence and high-spatial resolution resulting from small sensitive volumes. However, these detectors have not become commonplace due to high cost and poor availability arising from the need for high-quality diamond. We have fabricated relatively cheap detectors from commercially-available synthetic diamond fabricated using chemical vapour deposition. Here, we present a comparison of one of these detectors with the only commercially-available diamond-based detector (which uses a natural diamond crystal). Parameters such as the energy dependence and linearity of charge with dose were investigated at orthovoltage energies (50-250 kV), and dose-rate dependence of charge at linear accelerator energy (6 MV). The energy dependence of a synthetic diamond detector was similar to that of the natural diamond detector, albeit with slightly less variation across the energy range. Both detectors displayed a linear response with dose (at 100 kV) over the limited dose range used. The sensitivity of the synthetic diamond detector was 302 nC/Gy, compared to 294 nC/Gy measured for the natural diamond detector; however, this was obtained with a bias of 246.50 V compared to a bias of 61.75 V used for the natural diamond detector. The natural diamond detector exhibited a greater dependency on dose-rate than the synthetic diamond detector. Overall, the synthetic diamond detector performed well in comparison to the natural diamond detector.

Toroidal plasma enhanced CVD of diamond films

International Nuclear Information System (INIS)

Zvanya, John; Cullen, Christopher; Morris, Thomas; Krchnavek, Robert R.; Holber, William; Basnett, Andrew; Basnett, Robert; Hettinger, Jeffrey

2014-01-01

An inductively coupled toroidal plasma source is used as an alternative to microwave plasmas for chemical vapor deposition of diamond films. The source, operating at a frequency of 400 kHz, synthesizes diamond films from a mixture of argon, methane, and hydrogen. The toroidal design has been adapted to create a highly efficient environment for diamond film deposition: high gas temperature and a short distance from the sample to the plasma core. Using a toroidal plasma geometry operating in the medium frequency band allows for efficient (≈90%) coupling of AC line power to the plasma and a scalable path to high-power and large-area operation. In test runs, the source generates a high flux of atomic hydrogen over a large area, which is favorable for diamond film growth. Using a deposition temperature of 900–1050 °C and a source to sample distance of 0.1–2.0 cm, diamond films are deposited onto silicon substrates. The results showed that the deposition rate of the diamond films could be controlled using the sample temperature and source to sample spacing. The results also show the films exhibit good-quality polycrystalline diamond as verified by Raman spectroscopy, x-ray diffraction, and scanning electron microscopy. The scanning electron microscopy and x-ray diffraction results show that the samples exhibit diamond (111) and diamond (022) crystallites. The Raman results show that the sp 3 peak has a narrow spectral width (FWHM 12 ± 0.5 cm −1 ) and that negligible amounts of the sp 2 band are present, indicating good-quality diamond films

Diamond particle detectors systems in high energy physics

CERN Document Server

Gan, Kock Kiam

2015-01-01

The measurement of luminosity at the Large Hadron Collider (LHC) using diamond detect or s has matured from devices based on a rather large pads to highly granular pixelated device s . The ATLAS experiment has recently installed a diamond pixel detector, the Diamond Beam Monitor (DBM), to measure the luminosity in the upgraded LHC with higher instantaneous luminosity. Polycrystalline diamonds were used to fabricate the diamond pixel modules. The design , production, and test beam result s are described. CMS also has a similar plan to construct a diamond based luminosity monitor, the Pixel Luminos ity Telescope s (PLT) . In a pilot run using single crystal diamond, the pulse height was found to depend on the luminosity . Consequently the collaboration decided to use silicon instead due to time constrain ts .

Biofunctionalization of diamond microelectrodes

Energy Technology Data Exchange (ETDEWEB)

Reitinger, Andreas Adam; Lud, Simon Quartus; Stutzmann, Martin; Garrido, Jose Antonio [Walter Schottky Institut, TU Muenchen (Germany); Hutter, Naima Aurelia; Richter, Gerhard; Jordan, Rainer [WACKER-Chair of Macromolecular Chemistry, TU Muenchen (Germany)

2010-07-01

In this work we present two main routes for the biofunctionalization of nanocrystalline diamond films, aiming at the application of diamond microelectrodes as amperometric biosensors. We report on direct covalent grafting of biomolecules on nanocrystalline diamond films via diazonium monophenyls and biphenyls as well as other linker molecules, forming self-assembled monolayers on the diamond surface. Monolayers with different functional head groups have been characterized. Patterning of the available functional groups using electron beam-induced chemical lithography allows the selective preparation of well-localized docking sites for the immobilization of biomolecules. Furthermore, polymer brushes are expected to enable novel paths for designing more advanced biosensing schemes, incorporating multifunctional groups and a higher loading capacity for biomolecules. Here, we focus on the preparation of polymer grafts by self-initiated photografting and photopolymerization. Further chemical modification of the grafted polymer brushes results in the introduction of additional functional molecules, paving the way for the incorporation of more complex molecular structures such as proteins. In a comparative study we investigate the advantages and disadvantages of both approaches.

Het gelijk van Peter Singer: een ethische analyse

NARCIS (Netherlands)

Boer, Th.A.

2004-01-01

Volgens Peter Singer maakt de mens zich schuldig aan speciecisme, discriminatie van dieren t.o.v. mensen zuiver en alleen omdat we tot verschillende soorten behoren. Singers ethiek is omstreden, zoals mr. dr. M. de Blois betoogt in zijn artikel "Bij de beesten af. Een beschouwing over de ethiek van

Study on the Effect of Diamond Grain Size on Wear of Polycrystalline Diamond Compact Cutter

Science.gov (United States)

Abdul-Rani, A. M.; Che Sidid, Adib Akmal Bin; Adzis, Azri Hamim Ab

2018-03-01

Drilling operation is one of the most crucial step in oil and gas industry as it proves the availability of oil and gas under the ground. Polycrystalline Diamond Compact (PDC) bit is a type of bit which is gaining popularity due to its high Rate of Penetration (ROP). However, PDC bit can easily wear off especially when drilling hard rock. The purpose of this study is to identify the relationship between the grain sizes of the diamond and wear rate of the PDC cutter using simulation-based study with FEA software (ABAQUS). The wear rates of a PDC cutter with a different diamond grain sizes were calculated from simulated cuttings of cutters against granite. The result of this study shows that the smaller the diamond grain size, the higher the wear resistivity of PDC cutter.

Boron doped diamond electrode for the wastewater treatment

International Nuclear Information System (INIS)

Quiroz Alfaro, Marco Antonio; Ferro, Sergio; Martinez-Huitle, Carlos Alberto; Vong, Yunny Meas

2006-01-01

Electrochemical studies of diamond were started more than fifteen years ago with the first paper on diamond electrochemistry published by Pleskov. After that, work started in Japan, United States of America, France, Switzerland and other countries. Over the last few years, the number of publications has increased considerably. Diamond films have been the subject of applications and fundamental research in electrochemistry, opening up a new branch known as the electrochemistry of diamond electrodes. Here, we first present a brief history and the process of diamond film synthesis. The principal objective of this work is to summarize the most important results in the electrochemical oxidation using diamond electrodes. (author)

Optimizing biosensing properties on undecylenic Acid-functionalized diamond.

Science.gov (United States)

Zhong, Yu Lin; Chong, Kwok Feng; May, Paul W; Chen, Zhi-Kuan; Loh, Kian Ping

2007-05-08

The optimization of biosensing efficiency on a diamond platform depends on the successful coupling of biomolecules on the surface, and also on effective signal transduction in the biorecognition events. In terms of biofunctionalization of diamond surfaces, surface electrochemical studies of diamond modified with undecylenic acid (UA), with and without headgroup protection, were performed. The direct photochemical coupling method employing UA was found to impart a higher density of carboxylic acid groups on the diamond surface compared to that using trifluoroethyl undecenoate (TFEU) as the protecting group during the coupling process. Non-faradic impedimetric DNA sensing revealed that lightly doped diamond gives better signal transduction sensitivity compared to highly doped diamond.

Boron doped diamond electrode for the wastewater treatment

Directory of Open Access Journals (Sweden)

Alfaro Marco Antonio Quiroz

2006-01-01

Full Text Available Electrochemical studies of diamond were started more than fifteen years ago with the first paper on diamond electrochemistry published by Pleskov. After that, work started in Japan, United States of America, France, Switzerland and other countries. Over the last few years, the number of publications has increased considerably. Diamond films have been the subject of applications and fundamental research in electrochemistry, opening up a new branch known as the electrochemistry of diamond electrodes. Here, we first present a brief history and the process of diamond film synthesis. The principal objective of this work is to summarize the most important results in the electrochemical oxidation using diamond electrodes.

Detection and analysis of diamond fingerprinting feature and its application

Energy Technology Data Exchange (ETDEWEB)

Li Xin; Huang Guoliang; Li Qiang; Chen Shengyi, E-mail: tshgl@tsinghua.edu.cn [Department of Biomedical Engineering, the School of Medicine, Tsinghua University, Beijing, 100084 (China)

2011-01-01

Before becoming a jewelry diamonds need to be carved artistically with some special geometric features as the structure of the polyhedron. There are subtle differences in the structure of this polyhedron in each diamond. With the spatial frequency spectrum analysis of diamond surface structure, we can obtain the diamond fingerprint information which represents the 'Diamond ID' and has good specificity. Based on the optical Fourier Transform spatial spectrum analysis, the fingerprinting identification of surface structure of diamond in spatial frequency domain was studied in this paper. We constructed both the completely coherent diamond fingerprinting detection system illuminated by laser and the partially coherent diamond fingerprinting detection system illuminated by led, and analyzed the effect of the coherence of light source to the diamond fingerprinting feature. We studied rotation invariance and translation invariance of the diamond fingerprinting and verified the feasibility of real-time and accurate identification of diamond fingerprint. With the profit of this work, we can provide customs, jewelers and consumers with a real-time and reliable diamonds identification instrument, which will curb diamond smuggling, theft and other crimes, and ensure the healthy development of the diamond industry.

Engineering NV centres in Synthetic Diamond

International Nuclear Information System (INIS)

Matthew Markham

2014-01-01

The quantum properties of the nitrogen vacancy (NV) centre in diamond has prompted rapid growth in diamond research. This initial growth was driven by the fact the NV centre provides an 'easy' to manipulate quantum system along with opening up the possibility of a new material to deliver a solid state quantum computer. The NV defect is now moving from a quantum curiosity to a commercial development platform for a range of application such as as gyroscopes, timing and magnetometry as well as the more traditional quantum technologies such as quantum encryption and quantum simulation. These technologies are pushing the development needs of the material, and the processing of that material. The paper will describes the advances in CVD diamond synthesis with special attention to getting NV defects close to the surface of the diamond and how to process the material for diamond quantum optical applications. (author)

Short-range order in irradiated diamonds

International Nuclear Information System (INIS)

Agafonov, S.S.; Glazkov, V.P.; Nikolaenko, V.A.; Somenkov, V.A.

2005-01-01

Structural changes in irradiated diamond with a change in its density were studied. Natural diamond powders with average particle size from 14-20 μm to 0.5 mm, irradiated in beryllium block of the MR reactor up to a fluence of 1.51 x 10 21 were used as samples. Using the neutron-diffraction method, it has been established that, when density in irradiated diamonds varies, a transition from a diamond-like amorphous structure to a graphite-like structure occurs. The transition occurs at a density ρ ∼ 2.7-2.9 g/cm 3 and is accompanied by a sharp change in resistivity [ru

Vertically aligned nanowires from boron-doped diamond.

Science.gov (United States)

Yang, Nianjun; Uetsuka, Hiroshi; Osawa, Eiji; Nebel, Christoph E

2008-11-01

Vertically aligned diamond nanowires with controlled geometrical properties like length and distance between wires were fabricated by use of nanodiamond particles as a hard mask and by use of reactive ion etching. The surface structure, electronic properties, and electrochemical functionalization of diamond nanowires were characterized by atomic force microscopy (AFM) and scanning tunneling microscopy (STM) as well as electrochemical techniques. AFM and STM experiments show that diamond nanowire etched for 10 s have wire-typed structures with 3-10 nm in length and with typically 11 nm spacing in between. The electrode active area of diamond nanowires is enhanced by a factor of 2. The functionalization of nanowire tips with nitrophenyl molecules is characterized by STM on clean and on nitrophenyl molecule-modified diamond nanowires. Tip-modified diamond nanowires are promising with respect to biosensor applications where controlled biomolecule bonding is required to improve chemical stability and sensing significantly.

Prospects for the synthesis of large single-crystal diamonds

International Nuclear Information System (INIS)

Khmelnitskiy, R A

2015-01-01

The unique properties of diamond have stimulated the study of and search for its applications in many fields, including optics, optoelectronics, electronics, biology, and electrochemistry. Whereas chemical vapor deposition allows the growth of polycrystalline diamond plates more than 200 mm in diameter, most current diamond application technologies require large-size (25 mm and more) single-crystal diamond substrates or films suitable for the photolithography process. This is quite a challenge, because the largest diamond crystals currently available are 10 mm or less in size. This review examines three promising approaches to fabricating large-size diamond single crystals: growing large-size single crystals, the deposition of heteroepitaxial diamond films on single-crystal substrates, and the preparation of composite diamond substrates. (reviews of topical problems)

For a theory of children’s literature: Peter Hunt’s case

Directory of Open Access Journals (Sweden)

LEONARDO FRANCISCO SOARES

2015-08-01

Full Text Available As the first specialist in children's literature to be appointed Head Professor at a British university (The Cardiff University, when Peter Hunt chose children’s and youth literature as his PhD theme, he was told by his advisor that it was not a seriously enough subject. During the 1980s, there were no literary critics in Britain who focused on children’s and youth books analysis. Since then, Peter Hunt is devoted to thinking children's literature by a critical and theoretical bias. Thus, this paper aims to study the theoretical and critical issues raised by Peter Hunt in order to extract a specific theory of children's literature. In proposing to study children's literature by a theoretical bias instead of by a historical, cultural or emotional one, the English researcher is concerned with issues such as the concept of the book as an object, the notion of reader and reading (how do children construct meaning?, and especially the children's literature definition. These issues are raised into the broadest context of the Twentieth Century literary theory, making them more comprehensive and productive.

Mechanical pretreatment for improved adhesion of diamond coatings

International Nuclear Information System (INIS)

Toenshoff, H.K.; Mohlfeld, A.; Gey, C.; Winkler, J.

1999-01-01

Diamond coatings are mainly used in cutting processes due to their tribological characteristics. They show a high hardness, low friction coefficient, high wear resistance and good chemical inertness. In relation to polycrystalline diamond (PCD)-tipped cutting inserts, especially the advantageous chemical stability of diamond coatings is superior as no binder phases between diamond grains are used. However, the deposition of adherent high-quality diamond coatings has been found difficult. Thus, substrate pretreatment is utilised to improve film adhesion. This investigation is based on water peening of the substrate material before coating. The investigation revealed best results for diamond film adhesion on pretreated substrates compared to conventional diamond coatings on cemented carbide tools applied with the CVD hot-filament process. In final cutting tests with increased film adhesion trough water peened cutting tools an improved wear behavior was detected. (orig.)

Peter Greenaway: Ilusionista, Coleccionador, Narrador, Documentarista

Directory of Open Access Journals (Sweden)

Luís Nogueira

2009-08-01

Full Text Available In the title of this reflection I have attempted to summarize themultifaceted portrait of the author Peter Greenaway which I have outlined: conjurer and documentarian, collector and narrator. In the work of another author we might find clear dichotomies; in the case of Greenaway, we instead face slippery overlapping. The reflection that follows seeks to combine a possible response with a two-fold concern: to question the narrative taking as a starting point documentary and Greenaway cinema.

Peter Effect in the Preparation of Reading Teachers

Science.gov (United States)

Binks-Cantrell, Emily; Washburn, Erin K.; Joshi, R. Malatesha; Hougen, Martha

2012-01-01

The Peter Effect (Applegate & Applegate, 2004) claimed that one cannot be expected to give what one does not possess. We applied this notion to reading teacher preparation and hypothesized that teacher educators who do not possess an understanding of basic language constructs would not prepare teacher candidates with an understanding of these…

CVD diamond for nuclear detection applications

International Nuclear Information System (INIS)

Bergonzo, P.; Brambilla, A.; Tromson, D.; Mer, C.; Guizard, B.; Marshall, R.D.; Foulon, F.

2002-01-01

Chemically vapour deposited (CVD) diamond is a remarkable material for the fabrication of radiation detectors. In fact, there exist several applications where other standard semiconductor detectors do not fulfil the specific requirements imposed by corrosive, hot and/or high radiation dose environments. The improvement of the electronic properties of CVD diamond has been under intensive investigations and led to the development of a few applications that are addressing specific industrial needs. Here, we report on CVD diamond-based detector developments and we describe how this material, even though of a polycrystalline nature, is readily of great interest for applications in the nuclear industry as well as for physics experiments. Improvements in the material synthesis as well as on device fabrication especially concern the synthesis of films that do not exhibit space charge build up effects which are often encountered in CVD diamond materials and that are highly detrimental for detection devices. On a pre-industrial basis, CVD diamond detectors have been fabricated for nuclear industry applications in hostile environments. Such devices can operate in harsh environments and overcome limitations encountered with the standard semiconductor materials. Of these, this paper presents devices for the monitoring of the alpha activity in corrosive nuclear waste solutions, such as those encountered in nuclear fuel assembly reprocessing facilities, as well as diamond-based thermal neutron detectors exhibiting a high neutron to gamma selectivity. All these demonstrate the effectiveness of a demanding industrial need that relies on the remarkable resilience of CVD diamond

Diamond carbon sources: a comparison of carbon isotope models

International Nuclear Information System (INIS)

Kirkley, M.B.; Otter, M.L.; Gurney, J.J.; Hill, S.J.

1990-01-01

The carbon isotope compositions of approximately 500 inclusion-bearing diamonds have been determined in the past decade. 98 percent of these diamonds readily fall into two broad categories on the basis of their inclusion mineralogies and compositions. These categories are peridotitic diamonds and eclogitic diamonds. Most peridotitic diamonds have δ 13 C values between -10 and -1 permil, whereas eclogitic diamonds have δ 13 C values between -28 and +2 permil. Peridotitic diamonds may represent primordial carbon, however, it is proposed that initially inhomogeneous δ 13 C values were subsequently homogenized, e.g. during melting and convection that is postulated to have occurred during the first billion years of the earth's existence. If this is the case, then the wider range of δ 13 C values exhibited by eclogitic diamonds requires a different explanation. Both the fractionation model and the subduction model can account for the range of observed δ 13 C values in eclogitic diamonds. 16 refs., 2 figs

Air conditioning spaceship earth: Peter Sloterdijk's ethico-aesthetic paradigm

NARCIS (Netherlands)

S. van Tuinen (Sjoerd)

2009-01-01

textabstractAbstract. This paper explores the convergence of anthropology and ecology in the recent work of Peter Sloterdijk. Firstly, it is argued that Sloterdijk proposes an important new interpretation of Heideggerian Gelassenheit for which I propose the English word `relief '. The concept of

Nanostructured Diamond Device for Biomedical Applications.

Science.gov (United States)

Fijalkowski, M; Karczemska, A; Lysko, J M; Zybala, R; KozaneckI, M; Filipczak, P; Ralchenko, V; Walock, M; Stanishevsky, A; Mitura, S

2015-02-01

Diamond is increasingly used in biomedical applications because of its unique properties such as the highest thermal conductivity, good optical properties, high electrical breakdown voltage as well as excellent biocompatibility and chemical resistance. Diamond has also been introduced as an excellent substrate to make the functional microchip structures for electrophoresis, which is the most popular separation technique for the determination of analytes. In this investigation, a diamond electrophoretic chip was manufactured by a replica method using a silicon mold. A polycrystalline 300 micron-thick diamond layer was grown by the microwave plasma-assisted CVD (MPCVD) technique onto a patterned silicon substrate followed by the removal of the substrate. The geometry of microstructure, chemical composition, thermal and optical properties of the resulting free-standing diamond electrophoretic microchip structure were examined by CLSM, SFE, UV-Vis, Raman, XRD and X-ray Photoelectron Spectroscopy, and by a modified laser flash method for thermal property measurements.

Genesis of diamond inclusions: An integrated cathodoluminescence (CL) and Electron backscatter diffraction (EBSD) study on eclogitic and peridotitic inclusions and their diamond host.

Science.gov (United States)

van den Heuvel, Quint; Matveev, Sergei; Drury, Martyn; Gress, Michael; Chinn, Ingrid; Davies, Gareth

2017-04-01

Diamond inclusions are potentially fundamental to understanding the formation conditions of diamond and the volatile cycles in the deep mantle. In order to fully understand the implications of the compositional information recorded by inclusions it is vital to know whether the inclusions are proto-, syn-, or epigenetic and the extent to which they have equilibrated with diamond forming fluids. In previous studies, the widespread assumption was made that the majority of diamond inclusions are syngenetic, based upon observation of cubo-octahedral morphology imposed on the inclusions. Recent work has reported the crystallographic relationship between inclusions and the host diamond to be highly complex and the lack of crystallographic relationships between inclusions and diamonds has led some to question the significance of imposed cubo-octahedral morphology. This study presents an integrated EBSD and CL study of 9 diamonds containing 20 pyropes, 2 diopsides, 1 forsterite and 1 rutile from the Jwaneng and Letlhakane kimberlite clusters, Botswana. A new method was developed to analyze the crystallographic orientation of the host diamond and the inclusions with EBSD. Diamonds plates were sequentially polished to expose inclusions at different levels in the diamond. CL imaging at different depths was performed in order to produce a 3D view of diamond growth zones around the inclusions. Standard diamond polishing techniques proved too aggressive for silicate inclusions as they were damaged to such a degree that EBSD measurements on the inclusions were impossible. The inclusions were milled with a Ga+ focused ion beam (FIB) at a 12° angle to clean the surface for EBSD measurements. Of the 24 inclusions, 9 have an imposed cubo-octahedral morphology. Of these inclusions, 6 have faces orientated parallel to diamond growth zones and/or appear to have nucleated on a diamond growth surface, implying syngenesis. In contrast, other diamonds record resorption events such that

Portrait Face-Off: Gilbert Stuart vs. Peter Max

Science.gov (United States)

Crumpecker, Cheryl

2012-01-01

When art classes are short and infrequent, it is always a challenge to meet required state and national standards. A unit comparing and contrasting Peter Max's Pop art portraits with the realistic style of Gilbert Stuart's presidential portraits provides an opportunity to address a huge number of these requirements. Focus can change with the age…

R. S. Peters' "The Justification of Education" Revisited

Science.gov (United States)

Cuypers, Stefaan E.

2012-01-01

In his 1973 paper "The Justification of Education" R. S. Peters aspired to give a non-instrumental justification of education. Ever since, his so-called "transcendental argument" has been under attack and most critics conclude that it does not work. They have, however, thrown the baby away with the bathwater, when they furthermore concluded that…

New species of Temnocephala Blanchard (Platyhelminthes, Temnocephalida ectosymbiont on Aegla serrana Buckup & Rossi (Crustacea, Anomura from southern Brazil

Directory of Open Access Journals (Sweden)

José Felipe Ribeiro Amato

2003-09-01

Full Text Available A new species of the genus Temnocephala Blanchard, 1849 is described from southern Brazil, ectosymbiont on Aegla serrana Buckup & Rossi, 1977, an anomuran crustacean, collected in a creek and a reservoir of the highlands in the State of Rio Grande do Sul. All crustaceans examined were positive for this species of Temnocephala and carried eggs in different regions of the ventral side: perioral area, pleural strips, esternal plates, pereiopods and chelipods; to a lesser extent in the dorsal side of the cephalothorax and dorsal side of the uropods; as well as adult and young specimens. The most distinctive characters of the new species are: 1 cyanophilous glands forming an irregular-shaped, grape-like, bunch of approximately 10-15 cells, deeply staining with hematoxylin; 2 shape and size of the cirrus and its introvert section; 3 number, size and distribution of the rhabdite glands and 4 shape and position of the post tentacular, 'excretory' syncytial plates, with the off-centered nephridiopore.

CVD diamond detectors and dosimeters

International Nuclear Information System (INIS)

Manfredotti, C.; Fizzotti, F.; LoGiudice, A.; Paolini, C.; Oliviero, P.; Vittone, E.; Torino Univ., Torino

2002-01-01

Natural diamond, because of its well-known properties of tissue-equivalence, has recorded a wide spreading use in radiotherapy planning with electron linear accelerators. Artificial diamond dosimeters, as obtained by Chemical Vapour Deposition (CVD) could be capable to offer the same performances and they can be prepared in different volumes and shapes. The dosimeter sensitivity per unit volume may be easily proved to be better than standard ionization microchamber. We have prepared in our laboratory CVD diamond microchamber (diamond tips) in emispherical shape with an external diameter of 200 μm, which can be used both as X-ray beam profilometers and as microdosimeters for small field applications like stereotaxy and also for in vivo applications. These dosimeters, which are obtained on a wire substrate that could be either metallic or SiC or even graphite, display good performances also as ion or synchrotron X-rays detectors

Kolmanda aastatuhande piraadid / kommenteerinud Peter Chalk ja Gordan Van Hook

Index Scriptorium Estoniae

2009-01-01

Piraatlusest Somaalia piirkonnas ja rahvusvahelistest dokumentidest piraatluse vastu võitlemiseks 21. sajandil. Kommenteerivad uurimiskeskuse RAND Corporation vanempoliitanalüütik Peter Chalk ja transpordikompanii Maersk Line innovatsiooni ja arenduse vanemdirektor Gordan Van Hook

Diamond sensors for future high energy experiments

Energy Technology Data Exchange (ETDEWEB)

Bachmair, Felix, E-mail: bachmair@phys.ethz.ch

2016-09-21

With the planned upgrade of the LHC to High-Luminosity-LHC [1], the general purpose experiments ATLAS and CMS are planning to upgrade their innermost tracking layers with more radiation tolerant technologies. Chemical Vapor Deposition CVD diamond is one such technology. CVD diamond sensors are an established technology as beam condition monitors in the highest radiation areas of all LHC experiments. The RD42-collaboration at CERN is leading the effort to use CVD diamond as a material for tracking detectors operating in extreme radiation environments. An overview of the latest developments from RD42 is presented including the present status of diamond sensor production, a study of pulse height dependencies on incident particle flux and the development of 3D diamond sensors.

Diamond based adsorbents and their application in chromatography.

Science.gov (United States)

Peristyy, Anton A; Fedyanina, Olga N; Paull, Brett; Nesterenko, Pavel N

2014-08-29

The idea of using diamond and diamond containing materials in separation sciences has attracted a strong interest in the past decade. The combination of a unique range of properties, such as chemical inertness, mechanical, thermal and hydrolytic stability, excellent thermal conductivity with minimal thermal expansion and intriguing adsorption properties makes diamond a promising material for use in various modes of chromatography. This review summarises the recent research on the preparation of diamond and diamond based stationary phases, their properties and chromatographic performance. Special attention is devoted to the dominant retention mechanisms evident for particular diamond containing phases, and their subsequent applicability to various modes of chromatography, including chromatography carried out under conditions of high temperature and pressure. Copyright © 2014 Elsevier B.V. All rights reserved.

Surface temperature measurements of diamond

CSIR Research Space (South Africa)

Masina, BN

2006-07-01

Full Text Available Diamond has the highest thermal conductivity among known materials, and as such finds uses as an industrial tool in areas where dissipation of excess heat is a requirement. In this investigation we set up a laser system to heat a diamond sample...

Response of CVD diamond detectors to alpha radiation

Energy Technology Data Exchange (ETDEWEB)

Souw, E.-K. [Brookhaven National Lab., Upton, NY (United States); Meilunas, R.J. [Northrop-Grumman Corporation, Bethpage, NY 11714-3582 (United States)

1997-11-21

This article describes some results from an experiment with CVD diamond films used as {alpha} particle detectors. It demonstrates that bulk polarization can be effectively stopped within a reasonable time interval. This will enable detector calibration and quantitative measurement. A possible mechanism for the observed polarization quenching is discussed. It involves two types of carrier traps and a tentative band-gap model derived from the results of photoconductive current measurements. The experiment was set up mainly to investigate {alpha} detection properties of polycrystalline diamond films grown by the technique of microwave plasma enhanced chemical vapor deposition. For comparison, two commercially purchased diamond wafers were also investigated, i.e., one grown by the DC arc jet method, and the other, a type-IIa natural diamond wafer (not preselected). The best response to {alpha} particles was obtained using diamond thin-films grown by the microwave PECVD method, followed by the type-IIa natural diamond, and finally, the CVD diamond grown by the DC arc jet technique. (orig.). 43 refs.

Organophosphonate biofunctionalization of diamond electrodes.

Science.gov (United States)

Caterino, R; Csiki, R; Wiesinger, M; Sachsenhauser, M; Stutzmann, M; Garrido, J A; Cattani-Scholz, A; Speranza, Giorgio; Janssens, S D; Haenen, K

2014-08-27

The modification of the diamond surface with organic molecules is a crucial aspect to be considered for any bioapplication of this material. There is great interest in broadening the range of linker molecules that can be covalently bound to the diamond surface. In the case of protein immobilization, the hydropathicity of the surface has a major influence on the protein conformation and, thus, on the functionality of proteins immobilized at surfaces. For electrochemical applications, particular attention has to be devoted to avoid that the charge transfer between the electrode and the redox center embedded in the protein is hindered by a thick insulating linker layer. This paper reports on the grafting of 6-phosphonohexanoic acid on OH-terminated diamond surfaces, serving as linkers to tether electroactive proteins onto diamond surfaces. X-ray photoelectron spectroscopy (XPS) confirms the formation of a stable layer on the surface. The charge transfer between electroactive molecules and the substrate is studied by electrochemical characterization of the redox activity of aminomethylferrocene and cytochrome c covalently bound to the substrate through this linker. Our work demonstrates that OH-terminated diamond functionalized with 6-phosphonohexanoic acid is a suitable platform to interface redox-proteins, which are fundamental building blocks for many bioelectronics applications.

Conductive diamond electrodes for water purification

Directory of Open Access Journals (Sweden)

Carlos Alberto Martínez-Huitle

2007-12-01

Full Text Available Nowadays, synthetic diamond has been studied for its application in wastewater treatment, electroanalysis, organic synthesis and sensor areas; however, its use in the water disinfection/purification is its most relevant application. The new electrochemistry applications of diamond electrodes open new perspectives for an easy, effective, and chemical free water treatment. This article highlights and summarizes the results of a selection of papers dealing with electrochemical disinfection using synthetic diamond films.

Polycrystalline Diamond Schottky Diodes and Their Applications.

Science.gov (United States)

Zhao, Ganming

In this work, four-hot-filament CVD techniques for in situ boron doped diamond synthesis on silicon substrates were extensively studied. A novel tungsten filament shape and arrangement used to obtain large-area, uniform, boron doped polycrystalline diamond thin films. Both the experimental results and radiative heat transfer analysis showed that this technique improved the uniformity of the substrate temperature. XRD, Raman and SEM studies indicate that large area, uniform, high quality polycrystalline diamond films were obtained. Schottky diodes were fabricated by either sputter deposition of silver or thermal evaporation of aluminum or gold, on boron doped diamond thin films. High forward current density and a high forward-to-reverse current ratio were exhibited by silver on diamond Schottky diodes. Schottky barrier heights and the majority carrier concentrations of both aluminum and gold contacted diodes were determined from the C-V measurements. Furthermore, a novel theoretical C-V-f analysis of deep level boron doped diamond Schottky diodes was performed. The analytical results agree well with the experimental results. Compressive stress was found to have a large effect on the forward biased I-V characteristics of the diamond Schottky diodes, whereas the effect on the reverse biased characteristics was relatively small. The stress effect on the forward biased diamond Schottky diode was attributed to piezojunction and piezoresistance effects. The measured force sensitivity of the diode was as high as 0.75 V/N at 1 mA forward bias. This result shows that CVD diamond device has potential for mechanical transducer applications. The quantitative photoresponse characteristics of the diodes were studied in the spectral range of 300 -1050 nm. Semi-transparent gold contacts were used for better photoresponse. Quantum efficiency as high as 50% was obtained at 500 nm, when a reverse bias of over 1 volt was applied. The Schottky barrier heights between either gold or

My Journey with Peter: Moving Ideas that Matter

Science.gov (United States)

Blyth, Dale A.

2012-01-01

Youth development lost a pioneer and a champion, Peter Benson, in October. Benson was a pioneer whose ideas mattered and a champion of approaches to research and its use in the community that has made a difference around the world. Benson's work, life, and spirit have helped transform people's understanding of young people, what it takes to…

Diamond MEMS: wafer scale processing, devices, and technology insertion

Science.gov (United States)

Carlisle, J. A.

2009-05-01

Diamond has long held the promise of revolutionary new devices: impervious chemical barriers, smooth and reliable microscopic machines, and tough mechanical tools. Yet it's been an outsider. Laboratories have been effectively growing diamond crystals for at least 25 years, but the jump to market viability has always been blocked by the expense of diamond production and inability to integrate with other materials. Advances in chemical vapor deposition (CVD) processes have given rise to a hierarchy of carbon films ranging from diamond-like carbon (DLC) to vapor-deposited diamond coatings, however. All have pros and cons based on structure and cost, but they all share some of diamond's heralded attributes. The best performer, in theory, is the purest form of diamond film possible, one absent of graphitic phases. Such a material would capture the extreme hardness, high Young's modulus and chemical inertness of natural diamond. Advanced Diamond Technologies Inc., Romeoville, Ill., is the first company to develop a distinct chemical process to create a marketable phase-pure diamond film. The material, called UNCD® (for ultrananocrystalline diamond), features grain sizes from 3 to 300 nm in size, and layers just 1 to 2 microns thick. With significant advantages over other thin films, UNCD is designed to be inexpensive enough for use in atomic force microscopy (AFM) probes, microelectromechanical machines (MEMS), cell phone circuitry, radio frequency devices, and even biosensors.

Novel diamond-coated tools for dental drilling applications.

Science.gov (United States)

Jackson, M J; Sein, H; Ahmed, W; Woodwards, R

2007-01-01

The application of diamond coatings on cemented tungsten carbide (WC-Co) tools has been the subject of much attention in recent years in order to improve cutting performance and tool life in orthodontic applications. WC-Co tools containing 6% Co metal and 94% WC substrate with an average grain size of 1 - 3 microm were used in this study. In order to improve the adhesion between diamond and WC substrates it is necessary to etch cobalt from the surface and prepare it for subsequent diamond growth. Alternatively, a titanium nitride (TiN) interlayer can be used prior to diamond deposition. Hot filament chemical vapour deposition (HFCVD) with a modified vertical filament arrangement has been employed for the deposition of diamond films to TiN and etched WC substrates. Diamond film quality and purity has been characterized using scanning electron microscopy (SEM) and micro Raman spectroscopy. The performances of diamond-coated WC-Co tools, uncoated WC-Co tools, and diamond embedded (sintered) tools have been compared by drilling a series of holes into various materials such as human tooth, borosilicate glass, and acrylic tooth materials. Flank wear has been used to assess the wear rates of the tools when machining biomedical materials such as those described above. It is shown that using an interlayer such as TiN prior to diamond deposition provides the best surface preparation for producing dental tools.

Application of CVD diamond film for radiation detection

International Nuclear Information System (INIS)

Zhou Haiyang; Zhu Xiaodong; Zhan Rujuan

2005-01-01

With the development of diamond synthesis at low pressure, the CVD diamond properties including electronic characteristics have improved continuously. Now the fabrication of electronic devices based on the CVD diamond has been one of hot research subjects in this field. Due to many unique advantages, such as high signal-noise ratio, fast time response, and normal output in extremely harsh surrounding, the CVD diamond radiation detector has attracted more and more interest. In this paper, we have reviewed the development and status of the CVD diamond radiation detector. The prospect of this detector is described. (authors)

High-pressure-high-temperature treatment of natural diamonds

CERN Document Server

Royen, J V

2002-01-01

The results are reported of high-pressure-high-temperature (HPHT) treatment experiments on natural diamonds of different origins and with different impurity contents. The diamonds are annealed in a temperature range up to 2000 sup o C at stabilizing pressures up to 7 GPa. The evolution is studied of different defects in the diamond crystal lattice. The influence of substitutional nitrogen atoms, plastic deformation and the combination of these is discussed. Diamonds are characterized at room and liquid nitrogen temperature using UV-visible spectrophotometry, Fourier transform infrared spectrophotometry and photoluminescence spectrometry. The economic implications of diamond HPHT treatments are discussed.

Recent Advances in Diamond Detectors

CERN Document Server

Trischuk, W.

2008-01-01

With the commissioning of the LHC expected in 2009, and the LHC upgrades expected in 2012, ATLAS and CMS are planning for detector upgrades for their innermost layers requiring radiation hard technologies. Chemical Vapor Deposition (CVD) diamond has been used extensively in beam conditions monitors as the innermost detectors in the highest radiation areas of BaBar, Belle and CDF and is now planned for all LHC experiments. This material is now being considered as an alternate sensor for use very close to the interaction region of the super LHC where the most extreme radiation conditions will exist. Recently the RD42 collaboration constructed, irradiated and tested polycrystalline and single-crystal chemical vapor deposition diamond sensors to the highest fluences available. We present beam test results of chemical vapor deposition diamond up to fluences of 1.8 x 10^16 protons/cm^2 showing that both polycrystalline and single-crystal chemical vapor deposition diamonds follow a single damage curve allowing one t...

Otto Peters on Distance Education: The Industrialization of Teaching and Learning. Routledge Studies in Distance Education.

Science.gov (United States)

Keegan, Desmond, Ed.

This book contains new and previously published translations of 11 essays and articles about the industrialization of teaching and learning in distance education that were originally published in German by Otto Peters between 1965 and 1993. A "Preface" (Desmond Keegan) and an introduction placing Peters' writings in their historical…

Single-Crystal Diamond Nanobeam Waveguide Optomechanics

Science.gov (United States)

Khanaliloo, Behzad; Jayakumar, Harishankar; Hryciw, Aaron C.; Lake, David P.; Kaviani, Hamidreza; Barclay, Paul E.

2015-10-01

Single-crystal diamond optomechanical devices have the potential to enable fundamental studies and technologies coupling mechanical vibrations to both light and electronic quantum systems. Here, we demonstrate a single-crystal diamond optomechanical system and show that it allows excitation of diamond mechanical resonances into self-oscillations with amplitude >200 nm . The resulting internal stress field is predicted to allow driving of electron spin transitions of diamond nitrogen-vacancy centers. The mechanical resonances have a quality factor >7 ×105 and can be tuned via nonlinear frequency renormalization, while the optomechanical interface has a 150 nm bandwidth and 9.5 fm /√{Hz } sensitivity. In combination, these features make this system a promising platform for interfacing light, nanomechanics, and electron spins.

Modified diamond dies for laser applications

Energy Technology Data Exchange (ETDEWEB)

McWilliams, R.A.

1978-06-21

A modified wire drawing die for spatial filtering techniques is described. It was designed for use in high power laser systems. The diamond aperture is capable of enduring high intensity laser frequency without damaging the laser beam profile. The diamond is mounted at the beam focus in a vacuum of 1 x 10/sup -5/ Torr. The vacuum prevents plasma forming at the diamond aperture, thus enabling the beam to pass through without damaging the holder or aperture. The spatial filters are fitted with a manipulator that has three electronic stepping motors, can position the aperture in three orthogonal directions, and is capable of 3.2 ..mu..m resolution. Shiva laser system is using 105 diamond apertures for shaping the High Energy Laser Beam.

Education, Ethics and Values: A Response to Peter Blaze ...

African Journals Online (AJOL)

Education, Ethics and Values: A Response to Peter Blaze Corcoran's Keynote Address, EEASA 2003. ... while there is much value in the principles of the Earth Charter for guiding educational practice, educators should also consider some of the dilemmas of simply appropriating univeral ethical frameworks to guide practice.

Kunsti lastekodu / Stuart Bailey, Peter Bil'ak ; interv. Kristjan Mändmaa

Index Scriptorium Estoniae

Bailey, Stuart

2005-01-01

Rahvusvahelisest disainiajakirjast Dot Dot Dot. Väljaandjate slovakkia disaineri ja tüpograafi Peter Bil'aki ja inglise disaineri Stuart Bailey eluloolisi andmeid. Korraldavad õpikoja Eesti Kunstiakadeemias

UK Institute of Physics (IOP) President Sir Gareth Roberts (right) at CERN on 9 July with (right to left) IOP council vice-president and distinguished physicist Peter Kalmus, CERN engineer Tim Watson and IOP director of science Peter Cooper

CERN Multimedia

Patrice Loiez

1999-01-01

UK Institute of Physics (IOP) President Sir Gareth Roberts (right) at CERN on 9 July with (right to left) IOP council vice-president and distinguished physicist Peter Kalmus, CERN engineer Tim Watson and IOP director of science Peter Cooper

Reflections on Peters' View of the Nature and Purpose of Work in Philosophy of Education

Science.gov (United States)

Aspin, D. N.

2013-01-01

In this article I describe the analytic approach adopted by Peters, his colleagues and followers of the "London line" in the 1960s and 1970s and argue that, even in those times, other approaches to philosophy of education were being valued and practised. I show that Peters and his colleagues later became aware of the need for philosophy of…

First principles calculation of lithium-phosphorus co-doped diamond

Directory of Open Access Journals (Sweden)

Q.Y. Shao

2013-03-01

Full Text Available We calculate the density of states (DOS and the Mulliken population of the diamond and the co-doped diamonds with different concentrations of lithium (Li and phosphorus (P by the method of the density functional theory, and analyze the bonding situations of the Li-P co-doped diamond thin films and the impacts of the Li-P co-doping on the diamond conductivities. The results show that the Li-P atoms can promote the split of the diamond energy band near the Fermi level, and improve the electron conductivities of the Li-P co-doped diamond thin films, or even make the Li-P co-doped diamond from semiconductor to conductor. The affection of Li-P co-doping concentration on the orbital charge distributions, bond lengths and bond populations is analyzed. The Li atom may promote the split of the energy band near the Fermi level and also may favorably regulate the diamond lattice distortion and expansion caused by the P atom.

Comparison of natural and synthetic diamond X-ray detectors

International Nuclear Information System (INIS)

Lansley, S. P.; Betzel, G.T.; Meyer, J.; Metcalf, P.; Reinisch, L.

2010-01-01

Full text: Diamond detectors are particularly well suited for dosimetry applications in radiotherapy for reasons including near-tissue equivalence and high-spatial resolu tion resulting from small sensitive volumes. However, these detectors have not become commonplace due to high cost and poor availability arising from the need for high quality diamond. We have fabricated relatively cheap detectors from commercially-available synthetic diamond fabricated using chemical vapour deposition. Here, we present a comparison of one of these detectors with the only commercially-available diamond-based detector (which uses a natural diamond crystal). Parameters such as the energy dependence and linearity of charge with dose were investigated at orthovoltage energies (50-250 kY), and dose-rate dependence of charge at linear accelerator energy (6 MY). The energy dependence of a synthetic diamond detector was similar to that of the natural diamond detector, albeit with slightly less variation across the energy range. Both detectors displayed a linear response S. P. Lansley () . G. T. Betzel . J. Meyer Department of Physics and Astronomy, University of Canterbury, Christchurch, New Zealand e-mail: stuart.lansley canterbury.ac.nz S. P. Lansley The Macdiarmid Institute for Advanced Materials and Nanotechnology, University of Canterbury, Christchurch, New Zealand P. Metcalfe Centre for Medical Radiation Physics, University of Wollongong, Wollongong, Australia L. Reinisch Department of Physical and Earth Sciences, Jacksonville State University, Jacksonville, AL, USA with dose (at 100 kY) over the limited dose range used. The sensitivity of the synthetic diamond detector was 302 nC/Gy, compared to 294 nC/Gy measured for the natural diamond detector; however, this was obtained with a bias of 246.50 Y compared to a bias of 61.75 Y used for the natural diamond detector. The natural diamond detector exhibited a greater dependency on dose-rate than the syn thetic diamond detector. Overall

Investigation of laser ablation of CVD diamond film

Science.gov (United States)

Chao, Choung-Lii; Chou, W. C.; Ma, Kung-Jen; Chen, Ta-Tung; Liu, Y. M.; Kuo, Y. S.; Chen, Ying-Tung

2005-04-01

Diamond, having many advanced physical and mechanical properties, is one of the most important materials used in the mechanical, telecommunication and optoelectronic industry. However, high hardness value and extreme brittleness have made diamond extremely difficult to be machined by conventional mechanical grinding and polishing. In the present study, the microwave CVD method was employed to produce epitaxial diamond films on silicon single crystal. Laser ablation experiments were then conducted on the obtained diamond films. The underlying material removal mechanisms, microstructure of the machined surface and related machining conditions were also investigated. It was found that during the laser ablation, peaks of the diamond grains were removed mainly by the photo-thermal effects introduced by excimer laser. The diamond structures of the protruded diamond grains were transformed by the laser photonic energy into graphite, amorphous diamond and amorphous carbon which were removed by the subsequent laser shots. As the protruding peaks gradually removed from the surface the removal rate decreased. Surface roughness (Ra) was improved from above 1μm to around 0.1μm in few minutes time in this study. However, a scanning technique would be required if a large area was to be polished by laser and, as a consequence, it could be very time consuming.

Twinning of cubic diamond explains reported nanodiamond polymorphs

Science.gov (United States)

Németh, Péter; Garvie, Laurence A. J.; Buseck, Peter R.

2015-12-01

The unusual physical properties and formation conditions attributed to h-, i-, m-, and n-nanodiamond polymorphs has resulted in their receiving much attention in the materials and planetary science literature. Their identification is based on diffraction features that are absent in ordinary cubic (c-) diamond (space group: Fd-3m). We show, using ultra-high-resolution transmission electron microscope (HRTEM) images of natural and synthetic nanodiamonds, that the diffraction features attributed to the reported polymorphs are consistent with c-diamond containing abundant defects. Combinations of {113} reflection and rotation twins produce HRTEM images and d-spacings that match those attributed to h-, i-, and m-diamond. The diagnostic features of n-diamond in TEM images can arise from thickness effects of c-diamonds. Our data and interpretations strongly suggest that the reported nanodiamond polymorphs are in fact twinned c-diamond. We also report a new type of twin ( rotational), which can give rise to grains with dodecagonal symmetry. Our results show that twins are widespread in diamond nanocrystals. A high density of twins could strongly influence their applications.

Twinning of cubic diamond explains reported nanodiamond polymorphs.

Science.gov (United States)

Németh, Péter; Garvie, Laurence A J; Buseck, Peter R

2015-12-16

The unusual physical properties and formation conditions attributed to h-, i-, m-, and n-nanodiamond polymorphs has resulted in their receiving much attention in the materials and planetary science literature. Their identification is based on diffraction features that are absent in ordinary cubic (c-) diamond (space group: Fd-3m). We show, using ultra-high-resolution transmission electron microscope (HRTEM) images of natural and synthetic nanodiamonds, that the diffraction features attributed to the reported polymorphs are consistent with c-diamond containing abundant defects. Combinations of {113} reflection and rotation twins produce HRTEM images and d-spacings that match those attributed to h-, i-, and m-diamond. The diagnostic features of n-diamond in TEM images can arise from thickness effects of c-diamonds. Our data and interpretations strongly suggest that the reported nanodiamond polymorphs are in fact twinned c-diamond. We also report a new type of twin ( rotational), which can give rise to grains with dodecagonal symmetry. Our results show that twins are widespread in diamond nanocrystals. A high density of twins could strongly influence their applications.

CVD diamond metallization and characterization

Energy Technology Data Exchange (ETDEWEB)

Fraimovitch, D., E-mail: dimitryf@mail.tau.ac.il [Faculty of Engineering, Tel Aviv University, 69978 Tel Aviv (Israel); Adelberd, A.; Marunko, S. [Faculty of Engineering, Tel Aviv University, 69978 Tel Aviv (Israel); Lefeuvre, G. [Micron Semiconductor Ltd. Royal Buildings, Marlborough Road, Lancing Business Park, BN15 8SJ (United Kingdom); Ruzin, A. [Faculty of Engineering, Tel Aviv University, 69978 Tel Aviv (Israel)

2017-02-11

In this study we compared three diamond substrate grades: polycrystalline, optical grade single crystal, and electronic grade single crystal for detector application. Beside the bulk type, the choice of contact material, pre-treatment, and sputtering process details have shown to alter significantly the diamond detector performance. Characterization of diamond substrate permittivity and losses indicate grade and crystallinity related, characteristic differences for frequencies in 1 kHz–1 MHz range. Substantial grade related variations were also observed in surface electrostatic characterization performed by contact potential difference (CPD) mode of an atomic force microscope. Study of conductivity variations with temperature reveal that bulk trap energy levels are also dependent on the crystal grade.

CVD diamond metallization and characterization

International Nuclear Information System (INIS)

Fraimovitch, D.; Adelberd, A.; Marunko, S.; Lefeuvre, G.; Ruzin, A.

2017-01-01

In this study we compared three diamond substrate grades: polycrystalline, optical grade single crystal, and electronic grade single crystal for detector application. Beside the bulk type, the choice of contact material, pre-treatment, and sputtering process details have shown to alter significantly the diamond detector performance. Characterization of diamond substrate permittivity and losses indicate grade and crystallinity related, characteristic differences for frequencies in 1 kHz–1 MHz range. Substantial grade related variations were also observed in surface electrostatic characterization performed by contact potential difference (CPD) mode of an atomic force microscope. Study of conductivity variations with temperature reveal that bulk trap energy levels are also dependent on the crystal grade.

Tailoring nanocrystalline diamond coated on titanium for osteoblast adhesion.

Science.gov (United States)

Pareta, Rajesh; Yang, Lei; Kothari, Abhishek; Sirinrath, Sirivisoot; Xiao, Xingcheng; Sheldon, Brian W; Webster, Thomas J

2010-10-01

Diamond coatings with superior chemical stability, antiwear, and cytocompatibility properties have been considered for lengthening the lifetime of metallic orthopedic implants for over a decade. In this study, an attempt to tailor the surface properties of diamond films on titanium to promote osteoblast (bone forming cell) adhesion was reported. The surface properties investigated here included the size of diamond surface features, topography, wettability, and surface chemistry, all of which were controlled during microwave plasma enhanced chemical-vapor-deposition (MPCVD) processes using CH4-Ar-H2 gas mixtures. The hardness and elastic modulus of the diamond films were also determined. H2 concentration in the plasma was altered to control the crystallinity, grain size, and topography of the diamond coatings, and specific plasma gases (O2 and NH3) were introduced to change the surface chemistry of the diamond coatings. To understand the impact of the altered surface properties on osteoblast responses, cell adhesion tests were performed on the various diamond-coated titanium. The results revealed that nanocrystalline diamond (grain sizes diamond and, thus, should be further studied for improving orthopedic applications. Copyright 2010 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2010.

Marginal Experiments: Peter Brook and Stepping out Theatre Company

Science.gov (United States)

Harpin, Anna

2010-01-01

This article juxtaposes the recent work of Peter Brook with a Bristol-based mental health service-user collective--Stepping Out Theatre Company. Informed by field-work with the company, this chapter explores the aesthetic and political relationship between professional, experimental theatre work and community-based performance practice. Drawing…

R. S. Peters and the Concept of Education

Science.gov (United States)

Beckett, Kelvin Stewart

2011-01-01

In this essay Kelvin Beckett argues that Richard Peters's major work on education, "Ethics and Education," belongs on a short list of important texts we can all share. He argues this not because of the place it has in the history of philosophy of education, as important as that is, but because of the contribution it can still make to the future of…

Vision and Elusiveness in Philosophy of Education: R. S. Peters on the Legacy of Michael Oakeshott

Science.gov (United States)

Williams, Kevin

2009-01-01

Despite his elusiveness on important issues, there is much in Michael Oakeshott's educational vision that Richard Peters quite rightly wishes to endorse. The main aim of this essay is, however, to consider Peters' justifiable critique of three features of Oakeshott's work. These are (1) the rigidity of his distinction between vocational and…

Single-Crystal Diamond Nanobeam Waveguide Optomechanics

Directory of Open Access Journals (Sweden)

Behzad Khanaliloo

2015-12-01

Full Text Available Single-crystal diamond optomechanical devices have the potential to enable fundamental studies and technologies coupling mechanical vibrations to both light and electronic quantum systems. Here, we demonstrate a single-crystal diamond optomechanical system and show that it allows excitation of diamond mechanical resonances into self-oscillations with amplitude >200  nm. The resulting internal stress field is predicted to allow driving of electron spin transitions of diamond nitrogen-vacancy centers. The mechanical resonances have a quality factor >7×10^{5} and can be tuned via nonlinear frequency renormalization, while the optomechanical interface has a 150 nm bandwidth and 9.5  fm/sqrt[Hz] sensitivity. In combination, these features make this system a promising platform for interfacing light, nanomechanics, and electron spins.

Graphitization of diamond with a metallic coating on ferritic matrix

International Nuclear Information System (INIS)

Cabral, Stenio Cavalier; Oliveira, Hellen Cristine Prata de; Filgueira, Marcello

2010-01-01

Iron is a strong catalyst of graphitization of diamonds. This graphitization occurs mainly during the processing of composites - conventional sintering or hot pressing, and during cutting operations. Aiming to avoid or minimize this deleterious effect, there is increasing use of diamond coated with metallic materials in the production of diamond tools processed via powder metallurgy. This work studies the influence of Fe on diamond graphitization diamond-coated Ti after mixing of Fe-diamonds, hot pressing parameters were performed with 3 minutes/35MPa/900 deg C - this is the condition of pressing hot used in industry for production of diamond tools. Microstructural features were observed by SEM, diffusion of Fe in diamond was studied by EDS. Graphitization was analyzed by X-ray diffraction and Raman spectroscopy. It was found that Fe not activate graphitization on the diamond under the conditions of hot pressing. (author)

Polarized Raman spectroscopy of chemically vapour deposited diamond films

International Nuclear Information System (INIS)

Prawer, S.; Nugent, K.W.; Weiser, P.S.

1994-01-01

Polarized micro-Raman spectra of chemically vapour deposited diamond films are presented. It is shown that important parameters often extracted from the Raman spectra such as the ratio of the diamond to non-diamond component of the films and the estimation of the level of residual stress depend on the orientation of the diamond crystallites with respect to the polarization of the incident laser beam. The dependence originates from the fact that the Raman scattering from the non-diamond components in the films is almost completely depolarized whilst the scattering from the diamond components is strongly polarized. The results demonstrate the importance of taking polarization into account when attempting to use Raman spectroscopy in even a semi-quantitative fashion for the assessment of the purity, perfection and stress in CVD diamond films. 8 refs., 1 tab. 2 figs

Encapsulation of electroless copper patterns into diamond films

Energy Technology Data Exchange (ETDEWEB)

Pimenov, S.M.; Shafeev, G.A.; Lavrischev, S.V. [General Physics Institute, Moscow (Russian Federation)] [and others

1995-12-31

The results are reported on encapsulating copper lines into diamond films grown by a DC plasma CVD. The process includes the steps of (i) laser activation of diamond for electroless metal plating, (ii) electroless copper deposition selectively onto the activated surface regions, and (iii) diamond regrowth on the Cu-patterned diamond films. The composition and electrical properties of the encapsulated copper lines were examined, revealing high purity and low electrical resistivity of the encapsulated electroless copper.

Physics and applications of CVD diamond

CERN Document Server

Koizumi, Satoshi; Nesladek, Milos

2008-01-01

Here, leading scientists report on why and how diamond can be optimized for applications in bioelectronic and electronics. They cover such topics as growth techniques, new and conventional doping mechanisms, superconductivity in diamond, and excitonic properties, while application aspects include quantum electronics at room temperature, biosensors as well as diamond nanocantilevers and SAWs.Written in a review style to make the topic accessible for a wider community of scientists working in interdisciplinary fields with backgrounds in physics, chemistry, biology and engineering, this is e

Alluvial Diamond Resource Potential and Production Capacity Assessment of Ghana

Science.gov (United States)

Chirico, Peter G.; Malpeli, Katherine C.; Anum, Solomon; Phillips, Emily C.

2010-01-01

In May of 2000, a meeting was convened in Kimberley, South Africa, and attended by representatives of the diamond industry and leaders of African governments to develop a certification process intended to assure that rough, exported diamonds were free of conflictual concerns. This meeting was supported later in 2000 by the United Nations in a resolution adopted by the General Assembly. By 2002, the Kimberley Process Certification Scheme (KPCS) was ratified and signed by both diamond-producing and diamond-importing countries. Over 70 countries were included as members at the end of 2007. To prevent trade in 'conflict' diamonds while protecting legitimate trade, the KPCS requires that each country set up an internal system of controls to prevent conflict diamonds from entering any imported or exported shipments of rough diamonds. Every diamond or diamond shipment must be accompanied by a Kimberley Process (KP) certificate and be contained in tamper-proof packaging. The objective of this study was to assess the alluvial diamond resource endowment and current production capacity of the alluvial diamond-mining sector in Ghana. A modified volume and grade methodology was used to estimate the remaining diamond reserves within the Birim and Bonsa diamond fields. The production capacity of the sector was estimated using a formulaic expression of the number of workers reported in the sector, their productivity, and the average grade of deposits mined. This study estimates that there are approximately 91,600,000 carats of alluvial diamonds remaining in both the Birim and Bonsa diamond fields: 89,000,000 carats in the Birim and 2,600,000 carats in the Bonsa. Production capacity is calculated to be 765,000 carats per year, based on the formula used and available data on the number of workers and worker productivity. Annual production is highly dependent on the international diamond market and prices, the numbers of seasonal workers actively mining in the sector, and

Peters' Concept of "Education as Initiation": Communitarian or Individualist?

Science.gov (United States)

Cotter, Richard

2013-01-01

A central element of Richard Peters' philosophy of education has been his analysis of "education as initiation". Understanding initiation is internally related to concepts of community and what it may mean to be a member. The concept of initiation assumes a mutually interdependent, dynamic relationship between the individual and community that…

Polycrystalline diamond detectors with three-dimensional electrodes

Energy Technology Data Exchange (ETDEWEB)

Lagomarsino, S., E-mail: lagomarsino@fi.infn.it [University of Florence, Department of Physics, Via Sansone 1, 50019 Sesto Fiorentino (Italy); INFN Firenze, Via B. Rossi 1, 50019 Sesto Fiorentino (Italy); Bellini, M. [INO-CNR Firenze, Largo E. Fermi 6, 50125 Firenze (Italy); Brianzi, M. [INFN Firenze, Via B. Rossi 1, 50019 Sesto Fiorentino (Italy); Carzino, R. [Smart Materials-Nanophysics, Istituto Italiano di Tecnologia, Genova, Via Morego 30, 16163 Genova (Italy); Cindro, V. [Joseph Stefan Institute, Jamova Cesta 39, 1000 Ljubljana (Slovenia); Corsi, C. [University of Florence, Department of Physics, Via Sansone 1, 50019 Sesto Fiorentino (Italy); LENS Firenze, Via N. Carrara 1, 50019 Sesto Fiorentino (Italy); Morozzi, A.; Passeri, D. [INFN Perugia, Perugia (Italy); Università degli Studi di Perugia, Dipartimento di Ingegneria, via G. Duranti 93, 06125 Perugia (Italy); Sciortino, S. [University of Florence, Department of Physics, Via Sansone 1, 50019 Sesto Fiorentino (Italy); INFN Firenze, Via B. Rossi 1, 50019 Sesto Fiorentino (Italy); Servoli, L. [INFN Perugia, Perugia (Italy)

2015-10-01

The three-dimensional concept in diamond detectors has been applied, so far, to high quality single-crystal material, in order to test this technology in the best available conditions. However, its application to polycrystalline chemical vapor deposited diamond could be desirable for two reasons: first, the short inter-electrode distance of three-dimensional detectors should improve the intrinsically lower collection efficiency of polycrystalline diamond, and second, at high levels of radiation damage the performances of the poly-crystal material are not expected to be much lower than those of the single crystal one. We report on the fabrication and test of three-dimensional polycrystalline diamond detectors with several inter-electrode distances, and we demonstrate that their collection efficiency is equal or higher than that obtained with conventional planar detectors fabricated with the same material. - Highlights: • Pulsed laser fabrication of polycristalline diamond detectors with 3D electrodes. • Measurement of the charge collection efficiency (CCE) under beta irradiation. • Comparation between the CCE of 3D and conventional planar diamond sensors. • A rationale for the behavior of three-dimensional and planar sensors is given.

Use of the diamond to the detection of particles

International Nuclear Information System (INIS)

Mer, C.; Tromson, D.; Brambilla, A.; Foulon, F.; Guizard, B.; Bergonzo

2001-01-01

Diamond synthesized by chemical vapor deposition (CVD) is a valuable material for the detection of particles: broad forbidden energy band, high mobility of electron-hole pairs, and a short life-time of charge carriers. Diamond layers have been used in alpha detectors or gamma dose ratemeters designed to be used in hostile environment. Diamond presents a high resistance to radiation and corrosion. The properties of diamond concerning the detection of particles are spoilt by the existence of crystal defects even in high quality natural or synthesized diamond. This article presents recent works that have been performed in CEA laboratories in order to optimize the use of CVD diamond in particle detectors. (A.C.)

Direct Coating of Nanocrystalline Diamond on Steel

Science.gov (United States)

Tsugawa, Kazuo; Kawaki, Shyunsuke; Ishihara, Masatou; Hasegawa, Masataka

2012-09-01

Nanocrystalline diamond films have been successfully deposited on stainless steel substrates without any substrate pretreatments to promote diamond nucleation, including the formation of interlayers. A low-temperature growth technique, 400 °C or lower, in microwave plasma chemical vapor deposition using a surface-wave plasma has cleared up problems in diamond growth on ferrous materials, such as the surface graphitization, long incubation time, substrate softening, and poor adhesion. The deposited nanocrystalline diamond films on stainless steel exhibit good adhesion and tribological properties, such as a high wear resistance, a low friction coefficient, and a low aggression strength, at room temperature in air without lubrication.

Plecospondylic spinal column in the viviparous Cyprinodont Lebistes reticulatus (Peters)

NARCIS (Netherlands)

Stolk, A.

1955-01-01

Description of a case of plecospondylic spinal column in the viviparous Cyprinodont Lebistes reticulatus (PETERS), the so-called guppy or millionfish. In this deformity the following phenomena have been observed: displacement of vertebrae, transformation of vertebrae, increase in size of vertebrae,

Nanomechanical resonant structures in single-crystal diamond

OpenAIRE

Burek, Michael J.; Ramos, Daniel; Patel, Parth; Frank, Ian W.; Lončar, Marko

2013-01-01

With its host of outstanding material properties, single-crystal diamond is an attractive material for nanomechanical systems. Here, the mechanical resonance characteristics of freestanding, single-crystal diamond nanobeams fabricated by an angled-etching methodology are reported. Resonance frequencies displayed evidence of significant compressive stress in doubly clamped diamond nanobeams, while cantilever resonance modes followed the expected inverse-length-squared trend. Q-factors on the o...

Polycrystalline-Diamond MEMS Biosensors Including Neural Microelectrode-Arrays

Directory of Open Access Journals (Sweden)

Donna H. Wang

2011-08-01

Full Text Available Diamond is a material of interest due to its unique combination of properties, including its chemical inertness and biocompatibility. Polycrystalline diamond (poly-C has been used in experimental biosensors that utilize electrochemical methods and antigen-antibody binding for the detection of biological molecules. Boron-doped poly-C electrodes have been found to be very advantageous for electrochemical applications due to their large potential window, low background current and noise, and low detection limits (as low as 500 fM. The biocompatibility of poly-C is found to be comparable, or superior to, other materials commonly used for implants, such as titanium and 316 stainless steel. We have developed a diamond-based, neural microelectrode-array (MEA, due to the desirability of poly-C as a biosensor. These diamond probes have been used for in vivo electrical recording and in vitro electrochemical detection. Poly-C electrodes have been used for electrical recording of neural activity. In vitro studies indicate that the diamond probe can detect norepinephrine at a 5 nM level. We propose a combination of diamond micro-machining and surface functionalization for manufacturing diamond pathogen-microsensors.

Comparative evaluation of CVD diamond technologies

Energy Technology Data Exchange (ETDEWEB)

Anthony, T.R. [General Electric Corporate Research & Development Center, Schenectady, NY (United States)

1993-01-01

Chemical vapor deposition (CVD) of diamonds occurs from hydrogen-hydrocarbon gas mixtures in the presence of atomic hydrogen at subatmospheric pressures. Most CVD methods are based on different means of generating and transporting atomic hydrogen in a particular system. Evaluation of these different techniques involves their capital costs, material costs, energy costs, labor costs and the type and quality of diamond that they produce. Currently, there is no universal agreement on which is the best technique and technique selection has been largely driven by the professional background of the user as well as the particular application of interest. This article discusses the criteria for evaluating a process for low-pressure deposition of diamond. Next, a brief history of low-pressure diamond synthesis is reviewed. Several specific processes are addressed, including the hot filament process, hot filament electron-assisted chemical vapor deposition, and plasma generation of atomic hydrogen by glow discharge, microwave discharge, low pressure radio frequency discharge, high pressure DC discharge, high pressure microwave discharge jets, high pressure RF discharge, and high and low pressure flames. Other types of diamond deposition methods are also evaluated. 101 refs., 15 figs.

Effect of pretreatment and deposition parameters on diamond nucleation in CVD

International Nuclear Information System (INIS)

Nazim, E.; Izman, S.; Ourdjini, A.; Shaharoun, A.M.

2007-01-01

Chemical vapour deposition (CVD) of diamond films on cemented carbide (WC) has aroused great interest in recent years. The combination of toughness from the WC and the high hardness of diamond results in outstanding wear resistance. This will increase the lifetime and better technical performance of the components made of diamond coated carbide. One of the important steps in the growth of diamond film is the nucleation of diamond as its density strongly influences the diamond growth process, film quality and morphology. In this paper the various effects of surface pretreatment and diamond deposition conditions on the diamond nucleation density are reviewed. (author)

Preparation of Ti-coated diamond particles by microwave heating

International Nuclear Information System (INIS)

Gu, Quanchao; Peng, Jinghui; Xu, Lei; Srinivasakannan, C.

2016-01-01

Highlights: • The Ti-Coated diamond particles have been prepared using by microwave heating. • The uniform and dense coating can be produced, and the TiC species was formed. • With increases the temperature results in the thickness of coating increased. • The coating/diamond interfacial bonding strength increased with temperature increasing until 760 °C, then decreased. - Abstract: Depositing strong carbide-forming elements on diamond surface can dramatically improve the interfacial bonding strength between diamond grits and metal matrix. In the present work, investigation on the preparation of Ti-coated diamond particles by microwave heating has been conducted. The morphology, microstructure, and the chemical composition of Ti-coated diamond particles were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), and energy dispersive x-ray spectrometer (EDX). The thickness of Ti coating was measured and the interfacial binding strength between Ti coating and diamond was analyzed. The results show that the surface of the diamond particles could be successfully coated with Ti, forming a uniform and continuous Ti-coated layer. The TiC was found to form between the surface of diamond particles and Ti-coated layer. The amount of TiC as well as the thickness of coating increased with increasing coating temperature, furthermore, the grain size of the coating also grew gradually. The interfacial bonding strength between coating and diamond was found to be best at the temperature of 760 °C.

Preparation of Ti-coated diamond particles by microwave heating

Energy Technology Data Exchange (ETDEWEB)

Gu, Quanchao [National Local Joint Laboratory of Engineering Application of Microwave Energy and Equipment Technology, Faculty of Metallurgical and Energy Engineering, Kunming University of Science and Technology, Kunming 650093 (China); Yunnan Copper Smelting and Processing Complex, Yunnan Copper (Group) CO., LTD., Kunming 650102 (China); International Joint Research Center of Advanced Preparation of Superhard Materials Field, Kunming Academician Workstation of Advanced Preparation of Superhard Materials Field, Kunming 650093 (China); Peng, Jinghui [National Local Joint Laboratory of Engineering Application of Microwave Energy and Equipment Technology, Faculty of Metallurgical and Energy Engineering, Kunming University of Science and Technology, Kunming 650093 (China); International Joint Research Center of Advanced Preparation of Superhard Materials Field, Kunming Academician Workstation of Advanced Preparation of Superhard Materials Field, Kunming 650093 (China); Xu, Lei, E-mail: xulei_kmust@aliyun.com [National Local Joint Laboratory of Engineering Application of Microwave Energy and Equipment Technology, Faculty of Metallurgical and Energy Engineering, Kunming University of Science and Technology, Kunming 650093 (China); Mechanical Engineering, University of Washington, Seattle, WA 98195 (United States); International Joint Research Center of Advanced Preparation of Superhard Materials Field, Kunming Academician Workstation of Advanced Preparation of Superhard Materials Field, Kunming 650093 (China); Srinivasakannan, C. [Chemical Engineering Department, The Petroleum Institute, P.O. Box 2533, Abu Dhabi (United Arab Emirates); and others

2016-12-30

Highlights: • The Ti-Coated diamond particles have been prepared using by microwave heating. • The uniform and dense coating can be produced, and the TiC species was formed. • With increases the temperature results in the thickness of coating increased. • The coating/diamond interfacial bonding strength increased with temperature increasing until 760 °C, then decreased. - Abstract: Depositing strong carbide-forming elements on diamond surface can dramatically improve the interfacial bonding strength between diamond grits and metal matrix. In the present work, investigation on the preparation of Ti-coated diamond particles by microwave heating has been conducted. The morphology, microstructure, and the chemical composition of Ti-coated diamond particles were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), and energy dispersive x-ray spectrometer (EDX). The thickness of Ti coating was measured and the interfacial binding strength between Ti coating and diamond was analyzed. The results show that the surface of the diamond particles could be successfully coated with Ti, forming a uniform and continuous Ti-coated layer. The TiC was found to form between the surface of diamond particles and Ti-coated layer. The amount of TiC as well as the thickness of coating increased with increasing coating temperature, furthermore, the grain size of the coating also grew gradually. The interfacial bonding strength between coating and diamond was found to be best at the temperature of 760 °C.

A Review on the Low-Dimensional and Hybridized Nanostructured Diamond Films

Directory of Open Access Journals (Sweden)

Hongdong Li

2015-01-01

Full Text Available In the last decade, besides the breakthrough of high-rate growth of chemical vapor deposited single-crystal diamonds, numerous nanostructured diamond films have been rapidly developed in the research fields of the diamond-based sciences and industrial applications. The low-dimensional diamonds of two-dimensional atomic-thick nanofilms and nanostructural diamond on the surface of bulk diamond films have been theoretically and experimentally investigated. In addition, the diamond-related hybrid nanostructures of n-type oxide/p-type diamond and n-type nitride/p-type diamond, having high performance physical and chemical properties, are proposed for further applications. In this review, we first briefly introduce the three categories of diamond nanostructures and then outline the current advances in these topics, including their design, fabrication, characterization, and properties. Finally, we address the remaining challenges in the research field and the future activities.

Residual radioactivity of treated green diamonds.

Science.gov (United States)

Cassette, Philippe; Notari, Franck; Lépy, Marie-Christine; Caplan, Candice; Pierre, Sylvie; Hainschwang, Thomas; Fritsch, Emmanuel

2017-08-01

Treated green diamonds can show residual radioactivity, generally due to immersion in radium salts. We report various activity measurements on two radioactive diamonds. The activity was characterized by alpha and gamma ray spectrometry, and the radon emanation was measured by alpha counting of a frozen source. Even when no residual radium contamination can be identified, measurable alpha and high-energy beta emissions could be detected. The potential health impact of radioactive diamonds and their status with regard to the regulatory policy for radioactive products are discussed. Copyright © 2017. Published by Elsevier Ltd.

An assessment of radiotherapy dosimeters based on CVD grown diamond

International Nuclear Information System (INIS)

Ramkumar, S.; Buttar, C.M.; Conway, J.; Whitehead, A.J.; Sussman, R.S.; Hill, G.; Walker, S.

2001-01-01

Diamond is potentially a very suitable material for use as a dosimeter for radiotherapy. Its radiation hardness, the near tissue equivalence and chemical inertness are some of the characteristics of diamond, which make it well suited for its application as a dosimeter. Recent advances in the synthesis of diamond by chemical vapour deposition (CVD) technology have resulted in the improvement in the quality of material and increased its suitability for radiotherapy applications. We report in this paper, the response of prototype dosimeters based on two different types (CVD1 and CVD2) of CVD diamond to X-rays. The diamond devices were assessed for sensitivity, dependence of response on dose and dose rate, and compared with a Scanditronix silicon photon diode and a PTW natural diamond dosimeter. The diamond devices of CVD1 type showed an initial increase in response with dose, which saturates after ∼6 Gy. The diamond devices of CVD2 type had a response at low fields ( 1162.8 V/cm), the CVD2-type devices showed polarisation and dose-rate dependence. The sensitivity of the CVD diamond devices varied between 82 and 1300 nC/Gy depending upon the sample type and the applied voltage. The sensitivity of CVD diamond devices was significantly higher than that of natural diamond and silicon dosimeters. The results suggest that CVD diamond devices can be fabricated for successful use in radiotherapy applications

Morphology modulating the wettability of a diamond film.

Science.gov (United States)

Tian, Shibing; Sun, Weijie; Hu, Zhaosheng; Quan, Baogang; Xia, Xiaoxiang; Li, Yunlong; Han, Dong; Li, Junjie; Gu, Changzhi

2014-10-28

Control of the wetting property of diamond surface has been a challenge because of its maximal hardness and good chemical inertness. In this work, the micro/nanoarray structures etched into diamond film surfaces by a maskless plasma method are shown to fix a surface's wettability characteristics, and this means that the change in morphology is able to modulate the wettability of a diamond film from weakly hydrophilic to either superhydrophilic or superhydrophobic. It can be seen that the etched diamond surface with a mushroom-shaped array is superhydrophobic following the Cassie mode, whereas the etched surface with nanocone arrays is superhydrophilic in accordance with the hemiwicking mechnism. In addition, the difference in cone densities of superhydrophilic nanocone surfaces has a significant effect on water spreading, which is mainly derived from different driving forces. This low-cost and convenient means of altering the wetting properties of diamond surfaces can be further applied to underlying wetting phenomena and expand the applications of diamond in various fields.

Diamond detectors for synchrotron radiation X-ray applications

Energy Technology Data Exchange (ETDEWEB)

De Sio, A. [Laboratori Nazionali di Frascati, INFN, 00044 Frascati, Roma (Italy); Department of Astronomy and Space Science, Universita di Firenze, L.go E. Fermi 2, 50125 Firenze (Italy)], E-mail: desio@arcetri.astro.it; Pace, E. [Department of Astronomy and Space Science, Universita di Firenze, L.go E. Fermi 2, 50125 Firenze (Italy); INFN, Sezione di Firenze, v. G. Sansone 1, Sesto Fiorentino, Firenze (Italy); Cinque, G.; Marcelli, A. [Laboratori Nazionali di Frascati, INFN, 00044 Frascati, Roma (Italy); Achard, J.; Tallaire, A. [LIMHP-CNRS, University of Paris XIII, 99 Avenue JB Clement, 93430 Villetaneuse (France)

2007-07-15

Due to its unique physical properties, diamond is a very appealing material for the development of electronic devices and sensors. Its wide band gap (5.5 eV) endows diamond based devices with low thermal noise, low dark current levels and, in the case of radiation detectors, high visible-to-X-ray signal discrimination (visible blindness) as well as high sensitivity to energies greater than the band gap. Furthermore, due to its radiation hardness diamond is very interesting for applications in extreme environments, or as monitor of high fluency radiation beams. In this work the use of diamond based detectors for X-ray sensing is discussed. On purpose, some photo-conductors based on different diamond types have been tested at the DAFNE-L synchrotron radiation laboratory at Frascati. X-ray sensitivity spectra, linearity and stability of the response of these diamond devices have been measured in order to evidence the promising performance of such devices.

Diamond detectors for synchrotron radiation X-ray applications

International Nuclear Information System (INIS)

De Sio, A.; Pace, E.; Cinque, G.; Marcelli, A.; Achard, J.; Tallaire, A.

2007-01-01

Due to its unique physical properties, diamond is a very appealing material for the development of electronic devices and sensors. Its wide band gap (5.5 eV) endows diamond based devices with low thermal noise, low dark current levels and, in the case of radiation detectors, high visible-to-X-ray signal discrimination (visible blindness) as well as high sensitivity to energies greater than the band gap. Furthermore, due to its radiation hardness diamond is very interesting for applications in extreme environments, or as monitor of high fluency radiation beams. In this work the use of diamond based detectors for X-ray sensing is discussed. On purpose, some photo-conductors based on different diamond types have been tested at the DAFNE-L synchrotron radiation laboratory at Frascati. X-ray sensitivity spectra, linearity and stability of the response of these diamond devices have been measured in order to evidence the promising performance of such devices

Abnormal centromere-chromatid apposition (ACCA) and Peters' anomaly.

Science.gov (United States)

Wertelecki, W; Dev, V G; Superneau, D W

1985-08-01

Abnormal centromere-chromatid apposition (ACCA) was noted in a patient with Peters' anomaly. Previous reports of ACCA emphasized its association with tetraphocomelia and other congenital malformations (Roberts, SC Phocomelia, Pseudothalidomide Syndromes). This report expands the array of congenital malformations associated with ACCA and emphasizes the diagnostic importance of ocular defects for the ascertainment of additional cases of ACCA and its possible relationship with abnormal cell division.

Surface smoothening effects on growth of diamond films

Science.gov (United States)

Reshi, Bilal Ahmad; Kumar, Shyam; Kartha, Moses J.; Varma, Raghava

2018-04-01

We have carried out a detailed study of the growth dynamics of the diamond film during initial time on diamond substrates. The diamond films are deposited using Microwave Plasma Chemical Vapor Deposition (MPCVD) method for different times. Surface morphology and its correlation with the number of hours of growth of thin films was invested using atomic force microscopy (AFM). Diamond films have smooth interface with average roughness of 48.6873nm. The initial growth dynamics of the thin film is investigated. Interestingly, it is found that there is a decrease in the surface roughness of the film. Thus a smoothening effect is observed in the grown films. The film enters into the growth regime in the later times. Our results also find application in building diamond detector.

Dosimetry in radiotherapy with natural diamond detectors

International Nuclear Information System (INIS)

De Angelis, C.; Onori, S.; Pacilio, M.; Cirrone, G.A.P.; Cuttone, G.; Raffaele, L.; Bucciolini, M.; Mazzocchi, S.

2002-01-01

There is wide interest in the use of diamond detectors for dosimetry in radiotherapy mainly because of the small dimensions, radiation hardness, nearly tissue equivalence of sensitive material and capability to deliver the dosimetric response 'on line'. In order to assess the dosimetric properties of PTW Riga diamond detectors type 60003, experiments were performed in conventional (high energy photon and electron) therapy beams as well as in proton therapy beams. The main detector features investigated were reproducibility of response, dose-signal relationship, temperature dependence, dose-rate dependence, energy dependence and angular dependence. High energy photons (6-25 MV) and electrons (6-22 MeV), available at the Radiotherapy Department of the Florence University, were used for investigating the general properties. Two different PTW diamond detectors of the same type were used to evidence inter-sample differences. The beam quality dependence of the detector response is probably the most critical point and this statement is of particular relevance for proton dosimetry since the proton LET changes with depth in the medium. Mainly because of the little information available on detector sensitivity variations with beam energy, the use of diamonds for clinical proton dosimetry is not widespread. In two recent papers a sensitivity dependence on proton energy of a natural PTW diamond detector has been reported. Due to the necessity to characterise each diamond detector individually the PTW Riga natural diamond detector in operation at the LNS-INFN, Catania, Italy was tested with the local proton beam line. This experiment is of main concern because this proton beam, produced by a superconducting cyclotron and used for ocular melanoma treatment, is available only since 2001 (CATANA beam). The first patient has been treated in February 2002. Proton irradiations were performed with non modulated and modulated 62 MeV beams. Attention was focused on diamond sensitivity

Diamond thin films: giving biomedical applications a new shine.

Science.gov (United States)

Nistor, P A; May, P W

2017-09-01

Progress made in the last two decades in chemical vapour deposition technology has enabled the production of inexpensive, high-quality coatings made from diamond to become a scientific and commercial reality. Two properties of diamond make it a highly desirable candidate material for biomedical applications: first, it is bioinert, meaning that there is minimal immune response when diamond is implanted into the body, and second, its electrical conductivity can be altered in a controlled manner, from insulating to near-metallic. In vitro, diamond can be used as a substrate upon which a range of biological cells can be cultured. In vivo , diamond thin films have been proposed as coatings for implants and prostheses. Here, we review a large body of data regarding the use of diamond substrates for in vitro cell culture. We also detail more recent work exploring diamond-coated implants with the main targets being bone and neural tissue. We conclude that diamond emerges as one of the major new biomaterials of the twenty-first century that could shape the way medical treatment will be performed, especially when invasive procedures are required. © 2017 The Authors.

First result on biased CMOS MAPs-on-diamond devices

Energy Technology Data Exchange (ETDEWEB)

Kanxheri, K., E-mail: keida.kanxheri@pg.infn.it [Università degli Studi di Perugia, Perugia (Italy); INFN Perugia, Perugia (Italy); Citroni, M.; Fanetti, S. [LENS Firenze, Florence (Italy); Lagomarsino, S. [Università degli Studi di Firenze, Florence (Italy); INFN Firenze, Pisa (Italy); Morozzi, A. [Università degli Studi di Perugia, Perugia (Italy); INFN Perugia, Perugia (Italy); Parrini, G. [Università degli Studi di Firenze, Florence (Italy); Passeri, D. [Università degli Studi di Perugia, Perugia (Italy); INFN Perugia, Perugia (Italy); Sciortino, S. [Università degli Studi di Firenze, Florence (Italy); INFN Firenze, Pisa (Italy); Servoli, L. [INFN Perugia, Perugia (Italy)

2015-10-01

Recently a new type of device, the MAPS-on-diamond, obtained bonding a thinned to 25 μm CMOS Monolithic Active Pixel Sensor to a standard 500 μm pCVD diamond substrate, has been proposed and fabricated, allowing a highly segmented readout (10×10 μm pixel size) of the signal produced in the diamond substrate. The bonding between the two materials has been obtained using a new laser technique to deliver the needed energy at the interface. A biasing scheme has been adopted to polarize the diamond substrate to allow the charge transport inside the diamond without disrupting the functionalities of the CMOS Monolithic Active Pixel Sensor. The main concept of this class of devices is the capability of the charges generated in the diamond by ionizing radiation to cross the silicon–diamond interface and to be collected by the MAPS photodiodes. In this work we demonstrate that such passage occurs and measure its overall efficiency. This study has been carried out first calibrating the CMOS MAPS with monochromatic X-rays, and then testing the device with charged particles (electrons) either with and without biasing the diamond substrate, to compare the amount of signal collected.

Clinical dosimeter based on diamond detector

International Nuclear Information System (INIS)

Chervjakov, A.M.; Ljalina, L.I.; Ljutina, G.J.; Khrunov, V.S.; Martynov, S.S.; Popov, S.A.

2002-01-01

Full text: Diamond detectors have found application in the relative dosimetry and their parameters have been described elsewhere. Today, the exclusive producer of the diamond detector is the Institute of Physical and Technical Problems, Russia, and exclusive dealer is the PTW-Freiburg. The main features of the diamond detector are good long time stability, suitable range of the energy dependence for photon and electron beams in clinical use, independence of the measured date from temperature and pressure. The high sensitivity per volume unit of the diamond detector (1500 times higher than ionization chamber) allowed using detectors with very small volume (1-5 mm 3 ) and rather simple electronics for ionization current registration. The new dosimeter consists of the diamond detector itself, 40 m registration cable, pre-amplifier, micro-processor block for data handling and absorbed dose calculation using the calibration factor of diamond detector in terms of absorbed dose to water. Dosimeter has the possibility to work with PC using standard RS-232 interface. The main features of the dosimeter are as follows: the range of dose rate measurements for photon, electron and proton beams is within 0.01-1.0 Gy/s; the energy ranges for photons are 0.08-25 MeV, and 4-25 MeV for electrons, with energy dependence no more than ±2%; the main uncertainty of the dose measurements is within ±2%; the pre-irradiation dose for diamond detector is no more than 10 Gy; the sensitive volume of the used diamond detectors is within 1-5 mm 3 ; the weight of the dosimeter no more than 2 kg. The new dosimeter was evaluated at the Central Research Institute of Roentgenology and Radiology, St. Petersburg, Russia to verify its performance. The dosimeter was used as a reference instrument for dose measurements at Cobalt-60 unit, SL75-5 and SL-20 linear accelerators and the test results have shown that the device have met the specifications. It is planned to produce dosimeter as serial device by

Metastable State Diamond Growth and its Applications to Electronic Devices.

Science.gov (United States)

Jeng, David Guang-Kai

Diamond which consists of a dense array of carbon atoms joined by strong covalent bonds and formed into a tetrahedral crystal structure has remarkable mechanical, thermal, optical and electrical properties suitable for many industrial applications. With a proper type of doping, diamond is also an ideal semiconductor for high performance electronic devices. Unfortunately, natural diamond is rare and limited by its size and cost, it is not surprising that people continuously look for a synthetic replacement. It was believed for long time that graphite, another form of carbon, may be converted into diamond under high pressure and temperature. However, the exact condition of conversion was not clear. In 1939, O. I. Leipunsky developed an equilibrium phase diagram between graphite and diamond based on thermodynamic considerations. In the phase diagram, there is a low temperature (below 1000^ circC) and low pressure (below 1 atm) region in which diamond is metastable and graphite is stable, therefore establishes the conditions for the coexistence of the two species. Leipunsky's pioneer work opened the door for diamond synthesis. In 1955, the General Electric company (GE) was able to produce artificial diamond at 55k atm pressure and a temperature of 2000^ circC. Contrary to GE, B. Derjaguin and B. V. Spitzyn in Soviet Union, developed a method of growing diamonds at 1000^circC and at a much lower pressure in 1956. Since then, researchers, particularly in Soviet Union, are continuously looking for methods to grow diamond and diamond film at lower temperatures and pressures with slow but steady progress. It was only in the early 80's that the importance of growing diamond films had attracted the attentions of researchers in the Western world and in Japan. Recent progress in plasma physics and chemical vapor deposition techniques in integrated electronics technology have pushed the diamond growth in its metastable states into a new era. In this research, a microwave plasma

Science Matters Podcast: Questions and Answers with EPA's Dr. Peter Grevatt

Science.gov (United States)

Listen to a podcast with Dr. Peter Grevatt, the director of EPA's Office of Children's Health Protection, as he answers questions about children's health, or read some of the highlights from the conversation here.

President Ilves võõrustas Kanada ministrit Peter Van Loan'i

Index Scriptorium Estoniae

2010-01-01

President Toomas Hendrik Ilves kohtus 9. juulil 2010 Ärmal Kanada väliskaubandusministri Peter Van Loan'iga, kes mõjuka parlamendi- ja valitsuspoliitikuna aitas oluliselt kaasa Kanada valitsuse otsusele anda Eesti kodanikele viisavabadus

Diamond Detector Technology: Status and Perspectives

CERN Document Server

Reichmann, M; Artuso, M; Bachmair, F; Bäni, L; Bartosik, M; Beacham, J; Beck, H; Bellini, V; Belyaev, V; Bentele, B; Berdermann, E; Bergonzo, P; Bes, A; Brom, J-M; Bruzzi, M; Cerv, M; Chiodini, G; Chren, D; Cindro, V; Claus, G; Collot, J; Cumalat, J; Dabrowski, A; D'Alessandro, R; Dauvergne, D; de Boer, W; Dorfer, C; Dünser, M; Eremin, V; Eusebi, R; Forcolin, G; Forneris, J; Frais-Kölbl, H; Gallin-Martel, L; Gallin-Martel, M L; Gan, K K; Gastal, M; Giroletti, C; Goffe, M; Goldstein, J; Golubev, A; Gorišek, A; Grigoriev, E; Grosse-Knetter, J; Grummer, A; Gui, B; Guthoff, M; Haughton, I; Hiti, B; Hits, D; Hoeferkamp, M; Hofmann, T; Hosslet, J; Hostachy, J-Y; Hügging, F; Hutton, C; Jansen, H; Janssen, J; Kagan, H; Kanxheri, K; Kasieczka, G; Kass, R; Kassel, F; Kis, M; Konovalov, V; Kramberger, G; Kuleshov, S; Lacoste, A; Lagomarsino, S; Lo Giudice, A; Lukosi, E; Maazouzi, C; Mandic, I; Mathieu, C; Menichelli, M; Mikuž, M; Morozzi, A; Moss, J; Mountain, R; Murphy, S; Muškinja, M; Oh, A; Oliviero, P; Passeri, D; Pernegger, H; Perrino, R; Picollo, F; Pomorski, M; Potenza, R; Quadt, A; Re, A; Riley, G; Roe, S; Sanz-Becerra, D A; Scaringella, M; Schaefer, D; Schmidt, C J; Schnetzer, S; Sciortino, S; Scorzoni, A; Seidel, S; Servoli, L; Smith, S; Sopko, B; Sopko, V; Spagnolo, S; Spanier, S; Stenson, K; Stone, R; Sutera, C; Tannenwald, B; Taylor, A; Traeger, M; Tromson, D; Trischuk, W; Tuve, C; Uplegger, L; Velthuis, J; Venturi, N; Vittone, E; Wagner, S; Wallny, R; Wang, J C; Weingarten, J; Weiss, C; Wengler, T; Wermes, N; Yamouni, M; Zavrtanik, M

2018-01-01

The planned upgrade of the LHC to the High-Luminosity-LHC will push the luminosity limits above the original design values. Since the current detectors will not be able to cope with this environment ATLAS and CMS are doing research to find more radiation tolerant technologies for their innermost tracking layers. Chemical Vapour Deposition (CVD) diamond is an excellent candidate for this purpose. Detectors out of this material are already established in the highest irradiation regimes for the beam condition monitors at LHC. The RD42 collaboration is leading an effort to use CVD diamonds also as sensor material for the future tracking detectors. The signal behaviour of highly irradiated diamonds is presented as well as the recent study of the signal dependence on incident particle flux. There is also a recent development towards 3D detectors and especially 3D detectors with a pixel readout based on diamond sensors.

The characteristics of ESR and 3-D TL spectra of diamonds

International Nuclear Information System (INIS)

Liu Shunsheng; Lu Xu; Fu Huifang

2003-01-01

Electron Spin Resonance (ESR) and 3-dimensional Thermoluminescence (3-D TL) spectra of natural diamond, high temperature-high pressure artificial diamond and high temperature-low pressure chemical vapor deposited (CVD) diamond were determined. The characteristics of spectra have been studied. It is found that isolated nitrogen, nitrogen exchange pair and nitrogen atom pair (S=1) are main forms of electron spin resonance nitrogen in natural and high temperature-high pressure artificial diamonds. The spectrum of CVD diamond is sampler, and contains only one peak caused by suspended bond of unsaturated carbon ones. For 3-D TL spectra, natural diamond has two peaks (∼370 nm and ∼510 nm) in 100-200 degree C temperature range, high temperature-high pressure artificial diamond only has ∼370 nm peak, and CVD diamond only has ∼500 nm peak. These characteristics would be useful for the quality inspection and classification of diamonds, as well as for the study of geologic actions associated with natural diamond

Distance Education in Transition: new trends and challenges. Author: Otto Peters

Directory of Open Access Journals (Sweden)

Keith Harry

2003-10-01

Full Text Available I was delighted to be offered the chance to review this book because, although Professor Peters published Learning and Teaching in Distance Education: Pedagogical analyses and interpretations in an international perspective, in 1998, I hoped that this new volume would provide a new and different perspective on the most recent developments in distance education and in the role which Professor Peters has played in them. The subtitle of the new book, “New Trends and Challenges” seemed to justify my sense of anticipation. And to some extent the book does live up to expectations; it draws upon first-hand experience of the author as an online tutor who is clearly excited by the potential benefits of new technology for the teacher and, most importantly the learner.

Neutron detection at jet using artificial diamond detectors

International Nuclear Information System (INIS)

Pillon, M.; Angelone, M.; Lattanzi, D.; Marinelli, M.; Milani, E.; Tucciarone, A.; Verona-Rinati, G.; Popovichev, S.; Montereali, R.M.; Vincenti, M.A.; Murari, A.

2007-01-01

Artificial diamond neutron detectors recently proved to be promising devices to measure the neutron production on large experimental fusion machines. Diamond detectors are very promising detectors to be used in fusion environment due to their radiation hardness, low sensitivity to gamma rays, fast response and high energy resolution. High quality 'electronic grade' diamond films are produced through microwave chemical vapour deposition (CVD) technique. Two CVD diamond detectors have been installed and operated at joint European torus (JET), Culham Science Centre, UK. One of these detectors was a polycrystalline CVD diamond film; about 12 mm 2 area and 30 μm thickness while the second was a monocrystalline film of about 5 mm 2 area and 20 μm thick. Both diamonds were covered with 2 μm of lithium fluoride (LiF) 95% enriched in 6 Li. The LiF layer works as a neutron-to-charged particle converter so these detectors can measure thermalized neutrons. Their output signals were compared to JET total neutron yield monitors (KN1 diagnostic) realized with a set of uranium fission chambers. Despite their small active volumes the diamond detectors were able to measure total neutron yields with good reliability and stability during the recent JET experimental campaign of 2006

Characterization of diamond amorphized by ion implantation

International Nuclear Information System (INIS)

Allen, W.R.; Lee, E.H.

1992-01-01

Single crystal diamond has been implanted at 1 MeV with 2 x 10 20 Ar/m 2 . Rutherford backscattering spectrometry in a channeled geometry revealed a broad amorphized region underlying a thin, partially crystalline layer. Raman spectroscopy disclosed modifications in the bonding characteristic of the appearance of non-diamond carbon. The complementary nature of the two analysis techniques is demonstrated. The Knoop hardness of the implanted diamond was reduced by implantation

The Returns on Investment Grade Diamonds

NARCIS (Netherlands)

Renneboog, L.D.R.

2013-01-01

Abstract: This paper examines the risk-return characteristics of investment grade gems (white diamonds, colored diamonds and other types of gems including sapphires, rubies, and emeralds). The transactions are coming from gem auctions and span the period 1999-2012. Over our time frame, the annual

Fabrication of Diamond Based Sensors for Use in Extreme Environments

Directory of Open Access Journals (Sweden)

Gopi K. Samudrala

2015-04-01

Full Text Available Electrical and magnetic sensors can be lithographically fabricated on top of diamond substrates and encapsulated in a protective layer of chemical vapor deposited single crystalline diamond. This process when carried out on single crystal diamond anvils employed in high pressure research is termed as designer diamond anvil fabrication. These designer diamond anvils allow researchers to study electrical and magnetic properties of materials under extreme conditions without any possibility of damaging the sensing elements. We describe a novel method for the fabrication of designer diamond anvils with the use of maskless lithography and chemical vapor deposition in this paper. This method can be utilized to produce diamond based sensors which can function in extreme environments of high pressures, high and low temperatures, corrosive and high radiation conditions. We demonstrate applicability of these diamonds under extreme environments by performing electrical resistance measurements during superconducting transition in rare earth doped iron-based compounds under high pressures to 12 GPa and low temperatures to 10 K.

CN distribution in flame deposition of diamond and its relation to the growth rate, morphology, and nitrogen incorporation of the diamond layer

NARCIS (Netherlands)

Klein-Douwel, R.J.H.; Schermer, J.J.; Meulen, ter J.J.

1998-01-01

Two-dimensional laser-induced fluorescence (2D-LIF) measurements areapplied to the chemical vapour deposition (CVD) of diamond by anoxyacetylene flame to visualize the distribution of CN in the gas phaseduring the diamond growth process. The obtained diamond deposits arecharacterized by optical as

Toeplitz quantization and asymptotic expansions : Peter Weyl decomposition

Czech Academy of Sciences Publication Activity Database

Engliš, Miroslav; Upmeier, H.

2010-01-01

Roč. 68, č. 3 (2010), s. 427-449 ISSN 0378-620X R&D Projects: GA ČR GA201/09/0473 Institutional research plan: CEZ:AV0Z10190503 Keywords : bounded symmetric domain * real symmetric domain * star product * Toeplitz operator * Peter-Weyl decomposition Subject RIV: BA - General Mathematics Impact factor: 0.521, year: 2010 http://link.springer.com/article/10.1007%2Fs00020-010-1808-5

Neutron Detection at JET Using Artificial Diamond Detectors

International Nuclear Information System (INIS)

Pillon, M.; Angelone, M.; Lattanzi, D.; Milani, E.; Tucciarone, A.; Verona-Rinati, G.; Popovichev, S.; Murari, A.

2006-01-01

Three CVD diamond detectors are installed and operated at Joint European Torus, Culham laboratory. Diamond detectors are very promising detectors to be used in fusion environment due to their radiation hardness, gamma discrimination properties, fast response and spectroscopy properties. The aim of this work is to test and qualify artificial diamond detectors as neutron counters and spectrometers on a large fusion device. Two of these detectors are polycrystalline CVD diamond films of thickness 30 mm and 40 mm respectively while the third detector is a monocrystalline CVD of 110 mm thickness. The first polycrystalline diamond is covered with 4 mm of LiF 95 % enriched in 6 Li and enclosed inside a polyethylene moderator cap. This detector is used with a standard electronic chain made with a charge preamplifier, shaping amplifier and threshold discriminator. It is used to measure the time-dependent total neutron yield produced by JET plasma and its signal is compared with JET fission chambers. The second polycrystalline diamond is connected with a fast (1 GHz) preamplifier and a threshold discriminator via a long (about 100 m) double screened cable. This detector is used to detect the 14 MeV neutrons produced by triton burn-up using the reaction 12 C (n, α) 9 Be which occurs in diamond and a proper discriminator threshold. The response of this detector is fast and the electronic is far from the high radiation environment. Its signal is used in comparison with JET silicon diodes. The third monocrystalline diamond is also connected using a standard electronic and is used to demonstrate the feasibility of 14 MeV neutron spectrometry at about 3% peak resolution taking advantage of the spectrometer properties of monocrystalline diamonds. The results obtained are presented in this work. (author)

Tracing the Source of Borneo's Cempaka Diamond Deposit

Science.gov (United States)

White, L. T.; Graham, I.; Armstrong, R. A.; Hall, R.

2014-12-01

Several gem quality diamond deposits are found in paleo-alluvial deposits across Borneo. The source of the diamonds and their origin are enigmatic. They could have formed in Borneo and be derived from local sources, or they could be related to diamond deposits in NW Australia, and carried with the Southwest Borneo Block after it rifted from Australia in the Late Jurassic. We collected U-Pb isotopic data from detrital zircons from the Cempaka alluvial diamond deposit in southeast Borneo. Two thirds of the zircons that were dated crystallized between 75 Ma and 110 Ma. The other third are Triassic or older (223 Ma, 314-319 Ma, 353-367 Ma, 402-414 Ma, 474 Ma, 521 Ma, 549 Ma, 1135-1176 Ma, 1535 Ma, 2716 Ma). All of the Cretaceous zircons are angular, euhedral grains with minor evidence of mechanical abrasion. Considering their age and morphology they were likely derived from the nearby Schwaner Granites. The Triassic and older grains are rounded to semi-rounded and were likely derived from Australia before Borneo rifted from Gondwana. Some of the zircons have ages that resemble those of the Merlin and Argyle diamond deposits of Australia. The diamonds themselves have delicate resorption features and overgrowths that would potentially be destroyed with prolonged transport. Geochemical data collected from the diamonds implies they were associated with lamproite intrusions. Deep seismic lines and zircons from igneous rocks suggest SE Borneo, the East Java Sea and East Java are largely underlain by thick lithosphere rifted from NW Australia. Based on several lines of evidence, we propose that diamond-bearing lamproites intruded before rifting of SW Borneo from Australia, or after collision with Sundaland of SW Borneo and the East Java-West Sulawesi Blocks during the Cretaceous. Exposure of the source after the Late Cretaceous led to diamond accumulation in river systems that flowed from the Schwaner Mountains.

Diamond-based single-photon emitters

International Nuclear Information System (INIS)

Aharonovich, I; Castelletto, S; Simpson, D A; Su, C-H; Greentree, A D; Prawer, S

2011-01-01

The exploitation of emerging quantum technologies requires efficient fabrication of key building blocks. Sources of single photons are extremely important across many applications as they can serve as vectors for quantum information-thereby allowing long-range (perhaps even global-scale) quantum states to be made and manipulated for tasks such as quantum communication or distributed quantum computation. At the single-emitter level, quantum sources also afford new possibilities in terms of nanoscopy and bio-marking. Color centers in diamond are prominent candidates to generate and manipulate quantum states of light, as they are a photostable solid-state source of single photons at room temperature. In this review, we discuss the state of the art of diamond-based single-photon emitters and highlight their fabrication methodologies. We present the experimental techniques used to characterize the quantum emitters and discuss their photophysical properties. We outline a number of applications including quantum key distribution, bio-marking and sub-diffraction imaging, where diamond-based single emitters are playing a crucial role. We conclude with a discussion of the main challenges and perspectives for employing diamond emitters in quantum information processing.

The Nobel Prize winner in physics 2013--Peter Higgs

International Nuclear Information System (INIS)

Liu Jinyan

2014-01-01

Peter Higgs is a famous English physicist who was known for his works on Higgs mechanism and Higgs particle. He won the 2013 Noble Prize in physics. This paper briefly outlines his life, the proposition of Higgs mechanism and the origin of the name of Higgs particle. The discovery of Higgs particle is also given here. (author)

Food and feeding habits of Oreochromis mossambicus (Peters) in ...

African Journals Online (AJOL)

The diet of 745 Oreochromis mossambicus (Peters) of less than 0,5 up to 2000 g wet mass, in Hartbeespoort Dam, was determined from stomach content analysis. Samples of fish were selected to cover a whole annual cycle. Small fish fed initially on zoobenthos and zooplankton, but fish with a mass of over 4 g fed ...

75 FR 63533 - Gulf & Ohio Railways Holding Co., Inc., H. Peter Claussen and Linda C. Claussen-Continuance in...

Science.gov (United States)

2010-10-15

... DEPARTMENT OF TRANSPORTATION Surface Transportation Board [Docket No. FD 35414] Gulf & Ohio Railways Holding Co., Inc., H. Peter Claussen and Linda C. Claussen--Continuance in Control Exemption--Lancaster & Chester Railroad, LLC Gulf & Ohio Railways Holding Co., Inc. (G&O), H. Peter Claussen and Linda...

Diamond detectors for high energy physics experiments

Science.gov (United States)

Bäni, L.; Alexopoulos, A.; Artuso, M.; Bachmair, F.; Bartosik, M.; Beacham, J.; Beck, H.; Bellini, V.; Belyaev, V.; Bentele, B.; Berdermann, E.; Bergonzo, P.; Bes, A.; Brom, J.-M.; Bruzzi, M.; Cerv, M.; Chiodini, G.; Chren, D.; Cindro, V.; Claus, G.; Collot, J.; Cumalat, J.; Dabrowski, A.; D'Alessandro, R.; Dauvergne, D.; de Boer, W.; Dorfer, C.; Dünser, M.; Eremin, V.; Eusebi, R.; Forcolin, G.; Forneris, J.; Frais-Kölbl, H.; Gallin-Martel, L.; Gallin-Martel, M. L.; Gan, K. K.; Gastal, M.; Giroletti, C.; Goffe, M.; Goldstein, J.; Golubev, A.; Gorišek, A.; Grigoriev, E.; Grosse-Knetter, J.; Grummer, A.; Gui, B.; Guthoff, M.; Haughton, I.; Hiti, B.; Hits, D.; Hoeferkamp, M.; Hofmann, T.; Hosslet, J.; Hostachy, J.-Y.; Hügging, F.; Hutton, C.; Jansen, H.; Janssen, J.; Kagan, H.; Kanxheri, K.; Kasieczka, G.; Kass, R.; Kassel, F.; Kis, M.; Konovalov, V.; Kramberger, G.; Kuleshov, S.; Lacoste, A.; Lagomarsino, S.; Lo Giudice, A.; Lukosi, E.; Maazouzi, C.; Mandic, I.; Mathieu, C.; Menichelli, M.; Mikuž, M.; Morozzi, A.; Moss, J.; Mountain, R.; Murphy, S.; Muškinja, M.; Oh, A.; Oliviero, P.; Passeri, D.; Pernegger, H.; Perrino, R.; Picollo, F.; Pomorski, M.; Potenza, R.; Quadt, A.; Re, A.; Reichmann, M.; Riley, G.; Roe, S.; Sanz, D.; Scaringella, M.; Schaefer, D.; Schmidt, C. J.; Schnetzer, S.; Sciortino, S.; Scorzoni, A.; Seidel, S.; Servoli, L.; Smith, S.; Sopko, B.; Sopko, V.; Spagnolo, S.; Spanier, S.; Stenson, K.; Stone, R.; Sutera, C.; Tannenwald, B.; Taylor, A.; Traeger, M.; Tromson, D.; Trischuk, W.; Tuve, C.; Uplegger, L.; Velthuis, J.; Venturi, N.; Vittone, E.; Wagner, S.; Wallny, R.; Wang, J. C.; Weingarten, J.; Weiss, C.; Wengler, T.; Wermes, N.; Yamouni, M.; Zavrtanik, M.

2018-01-01

Beam test results of the radiation tolerance study of chemical vapour deposition (CVD) diamond against different particle species and energies is presented. We also present beam test results on the independence of signal size on incident particle rate in charged particle detectors based on un-irradiated and irradiated poly-crystalline CVD diamond over a range of particle fluxes from 2 kHz/cm2 to 10 MHz/cm2. The pulse height of the sensors was measured with readout electronics with a peaking time of 6 ns. In addition functionality of poly-crystalline CVD diamond 3D devices was demonstrated in beam tests and 3D diamond detectors are shown to be a promising technology for applications in future high luminosity experiments.

NEW HIGH STRENGTH AND FASTER DRILLING TSP DIAMOND CUTTERS

Energy Technology Data Exchange (ETDEWEB)

Robert Radtke

2006-01-31

The manufacture of thermally stable diamond (TSP) cutters for drill bits used in petroleum drilling requires the brazing of two dissimilar materials--TSP diamond and tungsten carbide. The ENDURUS{trademark} thermally stable diamond cutter developed by Technology International, Inc. exhibits (1) high attachment (shear) strength, exceeding 345 MPa (50,000 psi), (2) TSP diamond impact strength increased by 36%, (3) prevents TSP fracture when drilling hard rock, and (4) maintains a sharp edge when drilling hard and abrasive rock. A novel microwave brazing (MWB) method for joining dissimilar materials has been developed. A conventional braze filler metal is combined with microwave heating which minimizes thermal residual stress between materials with dissimilar coefficients of thermal expansion. The process results in preferential heating of the lower thermal expansion diamond material, thus providing the ability to match the thermal expansion of the dissimilar material pair. Methods for brazing with both conventional and exothermic braze filler metals have been developed. Finite element modeling (FEM) assisted in the fabrication of TSP cutters controllable thermal residual stress and high shear attachment strength. Further, a unique cutter design for absorbing shock, the densification of otherwise porous TSP diamond for increased mechanical strength, and diamond ion implantation for increased diamond fracture resistance resulted in successful drill bit tests.

Peter Bauer: Blazing the Trail of Development

OpenAIRE

Ian Vasquez

2007-01-01

Peter Bauer was a pioneer in development economics and his contributions to the field have been vindicated by the collapse of central planning. Through most of his career, however, Bauer was marginalized by the economics profession. Even after the fall of the Berlin Wall, economists frequently neglect Bauer’s work. Two survey articles on trade and development by Anne Krueger are presented as examples of that neglect. Bauer’s emphasis on choice, his interdisciplinary methodology, and his c...

Surface Structure of Aerobically Oxidized Diamond Nanocrystals

Science.gov (United States)

2014-10-27

Diamond. Phys. Rev. Lett. 2000, 84, 5160−5163. (31) Ownby, P. D.; Yang, X.; Liu, J. Calculated X-Ray-Diffraction Data for Diamond Polytypes. J. Am. Ceram...Surfaces from Ab-Initio Calculations . Phys. Rev. B 1995, 51, 14669−14685. (39) Ferrari, A. C.; Robertson, J. Raman Spectroscopy of Amorphous, Nanostructured...Y.; Takami, S.; Kubo , M.; Belosludov, R. V.; Miyamoto, A.; Imamura, A.; Gamo, M. N.; Ando, T. First-Principle Study on Reactions of Diamond (100

High-temperature Infrared Transmission of Free-standing Diamond Films

Directory of Open Access Journals (Sweden)

HEI Li-fu

2017-02-01

Full Text Available The combination of low absorption and extreme mechanical and thermal properties make diamond a compelling choice for some more extreme far infrared (8-12 μm window applications. The optical properties of CVD diamond at elevated temperatures are critical to many of these extreme applications. The infrared transmission of free-standing diamond films prepared by DC arc plasma jet were studied at temperature varied conditions. The surface morphology, structure feature and infrared optical properties of diamond films were tested by optical microscope, X-ray diffraction, laser Raman and Fourier-transform infrared spectroscopy. The results show that the average transmittance for 8-12μm is decreased from 65.95% at 27℃ to 52.5% at 500℃,and the transmittance drop is in three stages. Corresponding to the drop of transmittance with the temperature, diamond film absorption coefficient increases with the rise of temperature. The influence of the change of surface state of diamond films on the optical properties of diamond films is significantly greater than the influence on the internal structure.

P-type diamond stripper foils for tandem ion accelerators

International Nuclear Information System (INIS)

Phelps, A.W.; Koba, R.

1989-01-01

The authors are developing a stripper foil composed of a p-type diamond membrane. This diamond stripper foil should have a significantly longer lifetime than any conventional stripper foil material. To be useful for stripper foils, the boron-doped blue diamond films must be thinner than 0.8 μm and pore-free. Two methods are compared for their ability to achieve a high nucleation areal density on a W substrate. Some W substrates were first coated with think layer of boron (≤20 nm) in order to enhance nucleation. Other W substrates were scratched with submicron diamond particles. A schematic diagram of the stripper foil is shown. Stripper foils were created by etching away the central area of W substrates. The diamond membrane was then supported by an annulus of W. Tungsten was selected as a ring-support material because of its high electrical and thermal conductivity, relatively low thermal expansion, and proven suitability as a substrate for diamond CVD. Warping or fracture of the diamond film after substrate etch-back was investigated

Nanofocusing optics for synchrotron radiation made from polycrystalline diamond.

Science.gov (United States)

Fox, O J L; Alianelli, L; Malik, A M; Pape, I; May, P W; Sawhney, K J S

2014-04-07

Diamond possesses many extreme properties that make it an ideal material for fabricating nanofocusing x-ray optics. Refractive lenses made from diamond are able to focus x-ray radiation with high efficiency but without compromising the brilliance of the beam. Electron-beam lithography and deep reactive-ion etching of silicon substrates have been used in a transfer-molding technique to fabricate diamond optics with vertical and smooth sidewalls. Latest generation compound refractive lenses have seen an improvement in the quality and uniformity of the optical structures, resulting in an increase in their focusing ability. Synchrotron beamline tests of two recent lens arrays, corresponding to two different diamond morphologies, are described. Focal line-widths down to 210 nm, using a nanocrystalline diamond lens array and a beam energy of E = 11 keV, and 230 nm, using a microcrystalline diamond lens at E = 15 keV, have been measured using the Diamond Light Source Ltd. B16 beamline. This focusing prowess is combined with relatively high transmission through the lenses compared with silicon refractive designs and other diffractive optics.

Alluvial diamond resource potential and production capacity assessment of Mali

Science.gov (United States)

Chirico, Peter G.; Barthelemy, Francis; Kone, Fatiaga

2010-01-01

In May of 2000, a meeting was convened in Kimberley, South Africa, and attended by representatives of the diamond industry and leaders of African governments to develop a certification process intended to assure that rough, exported diamonds were free of conflictual concerns. This meeting was supported later in 2000 by the United Nations in a resolution adopted by the General Assembly. By 2002, the Kimberley Process Certification Scheme (KPCS) was ratified and signed by diamond-producing and diamond-importing countries. Over 70 countries were included as members of the KPCS at the end of 2007. To prevent trade in "conflict diamonds" while protecting legitimate trade, the KPCS requires that each country set up an internal system of controls to prevent conflict diamonds from entering any imported or exported shipments of rough diamonds. Every diamond or diamond shipment must be accompanied by a Kimberley Process (KP) certificate and be contained in tamper-proof packaging. The objective of this study was (1) to assess the naturally occurring endowment of diamonds in Mali (potential resources) based on geological evidence, previous studies, and recent field data and (2) to assess the diamond-production capacity and measure the intensity of mining activity. Several possible methods can be used to estimate the potential diamond resource. However, because there is generally a lack of sufficient and consistent data recording all diamond mining in Mali and because time to conduct fieldwork and accessibility to the diamond mining areas are limited, four different methodologies were used: the cylindrical calculation of the primary kimberlitic deposits, the surface area methodology, the volume and grade approach, and the content per kilometer approach. Approximately 700,000 carats are estimated to be in the alluvial deposits of the Kenieba region, with 540,000 carats calculated to lie within the concentration grade deposits. Additionally, 580,000 carats are estimated to have

Peter Hunt võttis vastu teenetemärgid / Silvia Paluoja

Index Scriptorium Estoniae

Paluoja, Silvia, 1956-

2010-01-01

AS Wendre suuromanik, Pärnumaa suurim tööandja Peter Hunt võttis 17. juunil 2010 Pärnu raekojas vastu talle president Toomas Hendrik Ilvese poolt annetatud Valgetähe IV klassi teenetemärgi ettevõtluse edendamise eest ning Pärnu linna vapimärgi

CVD diamond for nuclear detection applications

CERN Document Server

Bergonzo, P; Tromson, D; Mer, C; Guizard, B; Marshall, R D; Foulon, F

2002-01-01

Chemically vapour deposited (CVD) diamond is a remarkable material for the fabrication of radiation detectors. In fact, there exist several applications where other standard semiconductor detectors do not fulfil the specific requirements imposed by corrosive, hot and/or high radiation dose environments. The improvement of the electronic properties of CVD diamond has been under intensive investigations and led to the development of a few applications that are addressing specific industrial needs. Here, we report on CVD diamond-based detector developments and we describe how this material, even though of a polycrystalline nature, is readily of great interest for applications in the nuclear industry as well as for physics experiments. Improvements in the material synthesis as well as on device fabrication especially concern the synthesis of films that do not exhibit space charge build up effects which are often encountered in CVD diamond materials and that are highly detrimental for detection devices. On a pre-i...

Single-layer nano-carbon film, diamond film, and diamond/nano-carbon composite film field emission performance comparison

International Nuclear Information System (INIS)

Wang, Xiaoping; Wang, Jinye; Wang, Lijun

2016-01-01

A series of single-layer nano-carbon (SNC) films, diamond films, and diamond/nano-carbon (D/NC) composite films have been prepared on the highly doped silicon substrate by using microwave plasma chemical vapor deposition techniques. The films were characterised by scanning electron microscopy, Raman spectroscopy, and field emission I-V measurements. The experimental results indicated that the field emission maximum current density of D/NC composite films is 11.8–17.8 times that of diamond films. And the field emission current density of D/NC composite films is 2.9–5 times that of SNC films at an electric field of 3.0 V/μm. At the same time, the D/NC composite film exhibits the advantage of improved reproducibility and long term stability (both of the nano-carbon film within the D/NC composite cathode and the SNC cathode were prepared under the same experimental conditions). And for the D/NC composite sample, a high current density of 10 mA/cm"2 at an electric field of 3.0 V/μm was obtained. Diamond layer can effectively improve the field emission characteristics of nano-carbon film. The reason may be due to the diamond film acts as the electron acceleration layer.

Romantic Resonances in the Rhetoric of Peter Elbow's "Writing Without Teachers."

Science.gov (United States)

Yager, Kristi

1996-01-01

Seeks to uncover the historical roots within English Romanticism of Peter Elbow's thinking in order to show the depth and complexity of his assumptions about writing. Implicitly refutes charges questioning the intellectual credibility of Elbow's work. (TB)

Atomic structure-colour relationship in natural diamonds

International Nuclear Information System (INIS)

Godfrey, I S; Bangert, U

2010-01-01

Colour is a physical attribute that can be very difficult to characterise in diamond and consequently it receives regular attention from scientists working in the gem industry. In this work we compare natural brown (the most common colour) and colourless type IIa diamonds containing only trace quantities (< 1 at. ppm) of nitrogen. Numerous attempts have been made to trace the origin of brown tints in natural diamond, with the most likely culprits, i.e. dislocations and nitrogen impurities, ruled out through the application of various analytical techniques. Consequently more emphasis has recently been placed on the study of smaller defects in the diamond structure and their influence on colour. The focus of this research work is the analysis of vacancy defects having a size of the order of 1nm using aberration corrected scanning transmission electron microscopy (AC-STEM). The small electron probe size and depth of focus afforded by this technique allows such defect structures together with their position to be resolved far more readily than with conventional HR-TEM. Small-scale contrast variations are apparent in the lattice images of brown and not of colourless diamonds. These features have been compared to simulated phase contrast images of vacancy clusters in diamond. In addition, both experimental and simulated defocus series indicate that such features are not restricted to the surface of the specimen.

Bending diamonds by femtosecond laser ablation

DEFF Research Database (Denmark)

Balling, Peter; Esberg, Jakob; Kirsebom, Kim

2009-01-01

We present a new method based on femtosecond laser ablation for the fabrication of statically bent diamond crystals. Using this method, curvature radii of 1 m can easily be achieved, and the curvature obtained is very uniform. Since diamond is extremely tolerant to high radiation doses, partly due...

High vacuum tribology of polycrystalline diamond coatings

Indian Academy of Sciences (India)

Polycrystalline diamond coatings; hot filament CVD; high vacuum tribology. 1. Introduction .... is a characteristic of graphite. We mark the (diamond ... coefficient of friction due to changes in substrate temperature. The average coefficient of.

50 years of comparative biochemistry: The legacy of Peter Hochachka.

Science.gov (United States)

Buck, L T; Burness, G; Campbell, K L; Darveau, C-A; Driedzic, W; Guderley, H; McClelland, G B; Moon, T W; Moyes, C D; Schulte, P M

2018-02-28

Peter Hochachka was an early pioneer in the field of comparative biochemistry. He passed away in 2002 after 4 decades of research in the discipline. To celebrate his contributions and to coincide with what would have been his 80th birthday, a group of his former students organized a symposium that ran as a satellite to the 2017 Canadian Society of Zoologists annual meeting in Winnipeg, Manitoba (Canada). This Special Issue of CBP brings together manuscripts from symposium attendees and other authors who recognize the role Peter played in the evolution of the discipline. In this article, the symposium organizers and guest editors look back on his career, celebrating his many contributions to research, acknowledging his role in training of generations of graduate students and post-doctoral fellows in comparative biochemistry and physiology. Copyright © 2018. Published by Elsevier Inc.

The processing of heteroepitaxial thin-film diamond for electronic applications

International Nuclear Information System (INIS)

McGrath, J.

1998-09-01

Thin film diamond is of particular interest because of its wide applicability, including its potential use in high temperature electronics. This thesis describes a study of some of the processing stages required to exploit thin film diamond as an electronic device. Initial experiments were carried out to optimise bi-metallic contact schemes on orientated diamond film using electrical measurements and chemical analysis. Temperature stability was also investigated and it was concluded that the most favourable ohmic contact scheme is aluminium-on-titanium. Further electrical measurements confirmed that the contribution of resistance made by the contacts themselves to the metal/diamond/metal system overall was acceptably low, specifically 6 Ω.cm 2 for an undoped diamond system and less than 3 x 10 -6 Ω.cm 2 for boron doped diamond. To improve the as-grown resistivity of diamond films, an oxygen/argon plasma etch process was applied. The input parameters of the plasma system were optimised to give the maximum achievable resistivity of 4 x 10 11 Ω.cm. This was attained using a statistical design procedure via analysis of resistivity and etch rate outputs. Having optimised post growth treatment and contact metallisation, undoped and doped orientated diamond films were characterised via voltage and temperature dependencies. It was concluded that the dominant charge transport mechanisms for undoped diamond, nitrogen and boron doped diamond were variable range hopping at low temperatures up to 523 K and grain boundary effects. At higher temperatures, valence or impurity band conduction appeared to be the probable mechanisms with activation energies of 0.23 eV for nitrogen doped diamond and 0.08 eV for boron doped diamond. Preliminary experiments electrical properties of diamond and initial results suggested the presence of a high density of recombination centres. The final stage of experimental research initiated a study of direct electron beam writing lithography to

Diamond deposition on siliconized stainless steel

International Nuclear Information System (INIS)

Alvarez, F.; Reinoso, M.; Huck, H.; Rosenbusch, M.

2010-01-01

Silicon diffusion layers in AISI 304 and AISI 316 type stainless steels were investigated as an alternative to surface barrier coatings for diamond film growth. Uniform 2 μm thick silicon rich interlayers were obtained by coating the surface of the steels with silicon and performing diffusion treatments at 800 deg. C. Adherent diamond films with low sp 2 carbon content were deposited on the diffused silicon layers by a modified hot filament assisted chemical vapor deposition (HFCVD) method. Characterization of as-siliconized layers and diamond coatings was performed by energy dispersive X-ray analysis, scanning electron microscopy, X-ray diffraction and Raman spectroscopy.

Data science implications in diamond formation and craton evolution

Science.gov (United States)

Pan, F.; Huang, F.; Fox, P. A.

2017-12-01

Diamonds are so-called "messengers" from the deep Earth. Fluid and mineral inclusions in diamonds could reflect the compositions of fluids/melts and wall-rocks in which diamond formed. Recently many diamond samples are examined to study the water content in the mantle transition zone1, the mechanism of diamond formation2 and the mantle evolution history3. However, most of the studies can only explain local activities. Therefore, an overall project of data grouping, comparison and correlation is needed, but limited progress has been made due to a lack of benchmark datasets on diamond formation and effective computing algorithms. In this study, we start by proposing the very first complete and easily-accessible dataset on mineral and fluid inclusions in diamonds. We rescue, collect and organize the data available from papers, journals and other publications resources ([2-4] and more), and then apply several state-of-the-art machine learning methods to tackle this earth science problem by clustering diamond formation process into distinct groups primarily based on the compositions, the formation temperature and pressure, the age and so on. Our ongoing work includes further data exploration and training existing models. Our preliminary results show that diamonds formed from older cratons usually have higher formation temperature. Also peridotitic diamonds take a much larger population than the ecologitic ones. More details are being discovered when we finish constructing the database and training our model. We expect the result to demonstrate the advantages of using machine learning and data science in earth science research problems. Our methodology for knowledge discovery are very general and can be broadly applied to other earth science research problems under the same framework.[1] Pearson et al, Nature (2014); [2] Tomlinson et al, EPSL (2006); [3] Weiss et al, Nature (2016); [4] Stachel and Harris, Ore Geology Reviews (2008); Weiss et al, EPSL (2013)

Light volatiles in diamond: Physical interpretation and genetic significance

International Nuclear Information System (INIS)

Sellschop, J.P.F.; Madiba, C.C.P.; Annegarn, H.J.

1980-01-01

Natural diamond is characterised in terms of features in the infra-red and ultra-violet spectra. Additionally electron spin resonance, X-ray diffraction and topography, cathodoluminescence, mechanical and electrical measurements have been used to give more detail to such specification. It had been concluded that the major impurity in diamond was nitrogen and hence most physical phenomena have been interpreted as a manifestation of the mode(s) of occurence of nitrogen. From neutron activation analysis studies some 58 elements have been identified in diamond, many of course at trace levels. It has been shown that these data reveal a distinctive trace and minor element chemistry for diamond. Recently ion beam analyses have quantified the role of nitrogen in diamond characterisation. Most recently ion beam analysis has revealed that hydrogen, nitrogen and oxygen are all major impurities in diamond. Quantitative studies have been made using ( 19 Fe,α), (α,n) and ( 3 He,p) reactions. High temperature annealing in ultra-high vacuum conditions results in a substantial increase in the hydrogen measured as well as in the shape of the depth profile. Hydrogen is released from defect centres and diffuses rapidly through the diamond. Some of these hydrogen atoms are trapped at defect sites which are concentrated near surface as a result of the ion beam bombardement. A lesser response to the annealing treatment is found for oxygen and the smallest change for nitrogen. These ion beam data lend independent support to our earlier interpretation of the neutron activation data that all diamonds contain defects distributed fairly uniformly and consisting of sub-microscopic inclusions, the elemental composition of which suggests that each is a magma droplet from the upper mantle in which the diamond crystallized. The water-richness of the magma is an essential feature of the diamond genesis conditions. (orig.)

Cell adhesion and growth on ultrananocrystalline diamond and diamond-like carbon films after different surface modifications

Czech Academy of Sciences Publication Activity Database

Mikšovský, Jan; Voss, A.; Kozarova, R.; Kocourek, Tomáš; Písařík, Petr; Ceccone, G.; Kulisch, W.; Jelínek, Miroslav; Apostolova, M.D.; Reithmaier, J.P.; Popov, C.

2014-01-01

Roč. 297, APR (2014), s. 95-102 ISSN 0169-4332 R&D Projects: GA MŠk LD12069 Institutional support: RVO:68378271 Keywords : ultrananocrystalline diamond films * diamond -like carbon films * surface modification * direct contact cell tests Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 2.711, year: 2014 http://www.sciencedirect.com/science/article/pii/S0169433214001251

Influence of the microstructure of a diamond-containing composite material on the tool cutting ability when grinding a diamond single crystal

Directory of Open Access Journals (Sweden)

A.M. Kuzei

2017-12-01

Full Text Available Using the methods of electronic scanning microstructure and X-ray analysis, the influence of the structure of diamond-containing composite materials on the cutting ability of the tool for circular grinding of diamond single crystals has been studied. It is shown that the use of an oxide-hydroxide glass with a spreading temperature of 570–590 K as a precursor of the binder leads to the formation of melt films on the surface of silicon carbide and diamond particles at 600–630 K and the glass content in the batch is 10 vol. %. The conversion of oxidehydroxide glass films to oxide films proceeds at 700–775 K during the sintering of the composite material. Depending on the volume content of the glass in the charge, the porosity of the compact, three types of structure of composite materials are distinguished: a volumetric skeleton of glass-clad diamond particles and silicon carbide with pores at the sites of multiple compounds; a frame made of glass-clad diamond particles and silicon carbide with glass pores in places of multiple connections; a matrix of glass and the particles of diamond, silicon carbide and pores located in it. The maximum cutting ability of the tool for circular grinding of diamond is provided by a composite material with a structure of the first type.

The Forerunner of the Government Reform of Peter the Great

Directory of Open Access Journals (Sweden)

Nikita V. Shevtsov

2015-01-01

Full Text Available Abstract: This article describes the life and work of the distinguished political leader of the 17th century Vasiliy Vasilyevich Golitsyn. He entered the history of our country as a thoughtful reformist and a brilliant diplomat. His transformations created the foundation for the future pivotal reforms by Peter the Great. Being an outstanding analyst and a strategic planner, Golytsin won his combats not on the bloody battlefields but in the course of fights on the diplomatic arena. During the reign of Sophia, when he had received ultimately unlimited power warrant, he mainly fostered all of his efforts to the implementation of the socio-economic changes and the rise of prestige of the Russian State. However, as it often happens with the prominent reformists he became a victim of the in-house political tussle; he placed the wrong bet on Sophia instead of Peter the Great and his court. As a result, he was deprived from his post, lost his estates, and was sent into exile to the north of the country. The author of this article followed the probable route of Golytsin’s exile ramblings and paid special attention to the stay of the disgraced knyaz in Pinezhskiy Volok - currently the settlement of Pinega situated approximately 200 km away from Arkhangelsk on the banks of the Pinega River. The article also offers a detailed description of the Krasnogorskiy Monastery located 15 km away from the settlement. Golitsyn used to visit this monastery regularly and in 1714 was buried there disclaimed by Peter. The tombstone from his grave was preserved and is now stored in the Museum of Regional Studies in Pinega.

Ion channelling in diamond

International Nuclear Information System (INIS)

Derry, T.E.

1978-06-01

Diamond is one of the most extreme cases from a channelling point of view, having the smallest thermal vibration amplitude and the lowest atomic number of commonly-encountered crystals. These are the two parameters most important for determining channelling behaviour. It is of consiberable interest therefore to see how well the theories explaining and predicting the channeling properties of other substance, succeed with diamond. Natural diamond, although the best available form for these experiments, is rather variable in its physical properties. Part of the project was devoted to considering and solving the problem of obtaining reproducible results representative of the ideal crystal. Channelling studies were performed on several good crystals, using the Rutherford backscattering method. Critical angles for proton channelling were measured for incident energies from 0.6 to 4.5 MeV, in the three most open axes and three most open planes of the diamond structure, and for α-particle channelling at 0.7 and 1.0 MeV (He + ) in the same axes and planes. For 1.0 MeV protons, the crystal temperature was varied from 20 degrees Celsius to 700 degrees Celsius. The results are presented as curves of backscattered yield versus angle in the region of each axis or plane, and summarised in the form of tables and graphs. Generally the critical angles, axial minimum yields, and temperature dependence are well predicted by the accepted theories. The most valuable overall conclusion is that the mean thermal vibration amplitude of the atoms in a crytical determines the critical approach distance to the channel walls at which an ion can remain channelled, even when this distance is much smaller than the Thomas-Fermi screening distance of the atomic potential, as is the case in diamond. A brief study was made of the radiation damage caused by α-particle bombardment, via its effect on the channelling phenomenon. It was possible to hold damage down to negligible levels during the

Boron-doped diamond electrode: synthesis, characterization, functionalization and analytical applications.

Science.gov (United States)

Luong, John H T; Male, Keith B; Glennon, Jeremy D

2009-10-01

In recent years, conductive diamond electrodes for electrochemical applications have been a major focus of research and development. The impetus behind such endeavors could be attributed to their wide potential window, low background current, chemical inertness, and mechanical durability. Several analytes can be oxidized by conducting diamond compared to other carbon-based materials before the breakdown of water in aqueous electrolytes. This is important for detecting and/or identifying species in solution since oxygen and hydrogen evolution do not interfere with the analysis. Thus, conductive diamond electrodes take electrochemical detection into new areas and extend their usefulness to analytes which are not feasible with conventional electrode materials. Different types of diamond electrodes, polycrystalline, microcrystalline, nanocrystalline and ultrananocrystalline, have been synthesized and characterized. Of particular interest is the synthesis of boron-doped diamond (BDD) films by chemical vapor deposition on various substrates. In the tetrahedral diamond lattice, each carbon atom is covalently bonded to its neighbors forming an extremely robust crystalline structure. Some carbon atoms in the lattice are substituted with boron to provide electrical conductivity. Modification strategies of doped diamond electrodes with metallic nanoparticles and/or electropolymerized films are of importance to impart novel characteristics or to improve the performance of diamond electrodes. Biofunctionalization of diamond films is also feasible to foster several useful bioanalytical applications. A plethora of opportunities for nanoscale analytical devices based on conducting diamond is anticipated in the very near future.

High Heat Load Diamond Monochromator Project at ESRF

International Nuclear Information System (INIS)

Van aerenbergh, P.; Detlefs, C.; Haertwig, J.; Lafford, T. A.; Masiello, F.; Roth, T.; Schmid, W.; Wattecamps, P.; Zhang, L.

2010-01-01

Due to its outstanding thermal properties, diamond is an attractive alternative to silicon as a monochromator material for high intensity X-ray beams. To date, however, the practical applications have been limited by the small size and relatively poor crystallographic quality of the crystals available. The ESRF Diamond Project Group has studied the perfection of diamonds in collaboration with industry and universities. The group has also designed and tested different stress-free mounting techniques to integrate small diamonds into larger X-ray optical elements. We now propose to develop a water-cooled Bragg-Bragg double crystal monochromator using diamond (111) crystals. It will be installed on the ESRF undulator beamline, ID06, for testing under high heat load. This monochromator will be best suited for the low energy range, typically from ∼3.4 keV to 15 keV, due to the small size of the diamonds available and the size of the beam footprint. This paper presents stress-free mounting techniques studied using X-ray diffraction imaging, and their thermal-mechanical analysis by finite element modelling, as well as the status of the ID06 monochromator project.

Effect of temperature and relative-humidity on the development of Liriomyza sativae Blanchard (Diptera: Agromyzidae) in Vigna unguiculata; Efeito da temperatura e umidade relativa do ar no desenvolvimento de Liriomyza sativae Blanchard (Diptera: Agromyzidae) em Vigna unguiculata

Energy Technology Data Exchange (ETDEWEB)

Lima, Tiago C. Costa; Geremias, Leandro D; Parra, Jose R.P. [Escola Superior de Agricultura Luiz de Queiroz (ESALQ/USP), Piracicaba, SP (Brazil)], e-mail: tcclima@esalq.usp.br, e-mail: geremias@esalq.usp.br, e-mail: jrpparra@esalq.usp.br

2009-07-01

This research aimed to study the influence of temperature and relative-humidity (RH) on the development of Liriomyza sativae Blanchard during the egg-adult period, in cowpea, to provide essential information for future biological control projects against the pest. An inverse relation was observed between temperature increase in the range from 15 deg C to 32 deg C and development duration. Larval survival was not affected in the temperature range studied, while a high mortality of pupae was observed at 32 deg C (59.9%). RH did not affect the development time of the immature stages, although it influenced their survival. The lower developmental temperature threshold obtained for the egg-adult period was low (7.3 deg C) when compared with other species of Liriomyza, and was rather low for the larval stage (3.4 deg C ). Based on the thermal requirements for L. sativae, it was possible to estimate the occurrence of 24.5 annual generations at a melon producing region in state of Rio Grande do Norte, Brazil. For laboratory rearing aimed at biological control pest programs, the best rearing conditions are 30 deg C and 50% RH for the larval stage and 90% RH for the pupal stage. (author)

Temperature dependent simulation of diamond depleted Schottky PIN diodes

International Nuclear Information System (INIS)

Hathwar, Raghuraj; Dutta, Maitreya; Chowdhury, Srabanti; Goodnick, Stephen M.; Koeck, Franz A. M.; Nemanich, Robert J.

2016-01-01

Diamond is considered as an ideal material for high field and high power devices due to its high breakdown field, high lightly doped carrier mobility, and high thermal conductivity. The modeling and simulation of diamond devices are therefore important to predict the performances of diamond based devices. In this context, we use Silvaco ® Atlas, a drift-diffusion based commercial software, to model diamond based power devices. The models used in Atlas were modified to account for both variable range and nearest neighbor hopping transport in the impurity bands associated with high activation energies for boron doped and phosphorus doped diamond. The models were fit to experimentally reported resistivity data over a wide range of doping concentrations and temperatures. We compare to recent data on depleted diamond Schottky PIN diodes demonstrating low turn-on voltages and high reverse breakdown voltages, which could be useful for high power rectifying applications due to the low turn-on voltage enabling high forward current densities. Three dimensional simulations of the depleted Schottky PIN diamond devices were performed and the results are verified with experimental data at different operating temperatures

Temperature dependent simulation of diamond depleted Schottky PIN diodes

Science.gov (United States)

Hathwar, Raghuraj; Dutta, Maitreya; Koeck, Franz A. M.; Nemanich, Robert J.; Chowdhury, Srabanti; Goodnick, Stephen M.

2016-06-01

Diamond is considered as an ideal material for high field and high power devices due to its high breakdown field, high lightly doped carrier mobility, and high thermal conductivity. The modeling and simulation of diamond devices are therefore important to predict the performances of diamond based devices. In this context, we use Silvaco® Atlas, a drift-diffusion based commercial software, to model diamond based power devices. The models used in Atlas were modified to account for both variable range and nearest neighbor hopping transport in the impurity bands associated with high activation energies for boron doped and phosphorus doped diamond. The models were fit to experimentally reported resistivity data over a wide range of doping concentrations and temperatures. We compare to recent data on depleted diamond Schottky PIN diodes demonstrating low turn-on voltages and high reverse breakdown voltages, which could be useful for high power rectifying applications due to the low turn-on voltage enabling high forward current densities. Three dimensional simulations of the depleted Schottky PIN diamond devices were performed and the results are verified with experimental data at different operating temperatures

Temperature dependent simulation of diamond depleted Schottky PIN diodes

Energy Technology Data Exchange (ETDEWEB)

Hathwar, Raghuraj; Dutta, Maitreya; Chowdhury, Srabanti; Goodnick, Stephen M. [Department of Electrical Engineering, Arizona State University, Tempe, Arizona 85287-8806 (United States); Koeck, Franz A. M.; Nemanich, Robert J. [Department of Physics, Arizona State University, Tempe, Arizona 85287-8806 (United States)

2016-06-14

Diamond is considered as an ideal material for high field and high power devices due to its high breakdown field, high lightly doped carrier mobility, and high thermal conductivity. The modeling and simulation of diamond devices are therefore important to predict the performances of diamond based devices. In this context, we use Silvaco{sup ®} Atlas, a drift-diffusion based commercial software, to model diamond based power devices. The models used in Atlas were modified to account for both variable range and nearest neighbor hopping transport in the impurity bands associated with high activation energies for boron doped and phosphorus doped diamond. The models were fit to experimentally reported resistivity data over a wide range of doping concentrations and temperatures. We compare to recent data on depleted diamond Schottky PIN diodes demonstrating low turn-on voltages and high reverse breakdown voltages, which could be useful for high power rectifying applications due to the low turn-on voltage enabling high forward current densities. Three dimensional simulations of the depleted Schottky PIN diamond devices were performed and the results are verified with experimental data at different operating temperatures.

Cyclic voltammetry response of an undoped CVD diamond electrodes

Energy Technology Data Exchange (ETDEWEB)

Fabisiak, K., E-mail: kfab@ukw.edu.pl [Institute of Physics, Kazimierz Wielki University, Powstancow Wielkopolskich 2, 85-090 Bydgoszcz (Poland); Torz-Piotrowska, R. [Faculty of Chemical Technology and Engineering, UTLS Seminaryjna 3, 85-326 Bydgoszcz (Poland); Staryga, E. [Institute of Physics, Technical University of Lodz, Wolczanska 219, 90-924 Lodz (Poland); Szybowicz, M. [Faculty of Technical Physics, Poznan University of Technology, Nieszawska 13A, 60-965 Poznan (Poland); Paprocki, K.; Popielarski, P.; Bylicki, F. [Institute of Physics, Kazimierz Wielki University, Powstancow Wielkopolskich 2, 85-090 Bydgoszcz (Poland); Wrzyszczynski, A. [Institute of Physics, Technical University of Lodz, Wolczanska 219, 90-924 Lodz (Poland)

2012-09-01

Highlights: Black-Right-Pointing-Pointer Correlation was found between diamond quality and its electrochemical performance. Black-Right-Pointing-Pointer The electrode sensitivity depends on the content of sp{sup 2} carbon phase in diamond layer. Black-Right-Pointing-Pointer The sp{sup 2} carbon phase content has little influence on the CV peak separation ({Delta}E{sub p}). - Abstract: The polycrystalline undoped diamond layers were deposited on tungsten wire substrates by using hot filament chemical vapor deposition (HFCVD) technique. As a working gas the mixture of methanol in excess of hydrogen was used. The morphologies and quality of as-deposited films were monitored by means of scanning electron microscopy (SEM), X-ray diffraction (XRD) and Raman spectroscopy respectively. The electrochemical activity of the obtained diamond layers was monitored by using cyclic voltammetry measurements. Analysis of the ferrocyanide-ferricyanide couple at undoped diamond electrode suggests that electrochemical reaction at diamond electrode has a quasireversibile character. The ratio of the anodic and cathodic peak currents was always close to unity. In this work we showed that the amorphous carbon admixture in the CVD diamond layer has a crucial influence on its electrochemical performance.

New developments in CVD diamond for detector applications

Science.gov (United States)

Adam, W.; Berdermann, E.; Bergonzo, P.; de Boer, W.; Bogani, F.; Borchi, E.; Brambilla, A.; Bruzzi, M.; Colledani, C.; Conway, J.; D'Angelo, P.; Dabrowski, W.; Delpierre, P.; Dulinski, W.; Doroshenko, J.; van Eijk, B.; Fallou, A.; Fischer, P.; Fizzotti, F.; Furetta, C.; Gan, K. K.; Ghodbane, N.; Grigoriev, E.; Hallewell, G.; Han, S.; Hartjes, F.; Hrubec, J.; Husson, D.; Kagan, H.; Kaplon, J.; Kass, R.; Keil, M.; Knoepfle, K. T.; Koeth, T.; Krammer, M.; Logiudice, A.; Lu, R.; Mac Lynne, L.; Manfredotti, C.; Meier, D.; Menichelli, D.; Meuser, S.; Mishina, M.; Moroni, L.; Noomen, J.; Oh, A.; Pernicka, M.; Perera, L.; Potenza, R.; Riester, J. L.; Roe, S.; Rudge, A.; Sala, S.; Sampietro, M.; Schnetzer, S.; Sciortino, S.; Stelzer, H.; Stone, R.; Sutera, C.; Trischuk, W.; Tromson, D.; Tuve, C.; Vincenzo, B.; Weilhammer, P.; Wermes, N.; Wetstein, M.; Zeuner, W.; Zoeller, M.

Chemical Vapor Deposition (CVD) diamond has been discussed extensively as an alternative sensor material for use very close to the interaction region of the LHC and other machines where extreme radiation conditions exist. During the last seven years the RD42 collaboration has developed diamond detectors and tested them with LHC electronics towards the end of creating a device usable by experiments. The most recent results of this work are presented. Recently, a new form of CVD diamond has been developed: single crystal CVD diamond which resolves many of the issues associated with poly-crystalline CVD material. The first tests of this material are also presented.

New developments in CVD diamond for detector applications

Energy Technology Data Exchange (ETDEWEB)

Adam, W. [HEPHY, Vienna (Austria); Berdermann, E. [GSI, Darmstadt (Germany); Bergonzo, P.; Brambilla, A. [LETI/DEIN/SPE/CEA Saclay (France); Boer, W. de [Universitaet Karlsruhe, Karlsruhe (Germany); Bogani, F. [LENS, Florence (Italy); Borchi, E.; Bruzzi, M. [University of Florence (Italy); Colledani, C.; Dulinski, W. [LEPSI, IN2P3/CNRS-ULP, Strasbourg (France); Conway, J.; Doroshenko, J. [Rutgers University, Piscataway (United States); D' Angelo, P.; Furetta, C. [INFN, Milano (Italy); Dabrowski, W. [UMM, Cracow (Poland); Delpierre, P.; Fallou, A. [CPPM, Marseille (France); Eijk, B. van [NIKHEF, Amsterdam (Netherlands); Fischer, P. [Universitaet Bonn, Bonn (Germany); Fizzotti, F. [University of Torino (Italy); Gan, K.K.; Ghodbane, N.; Grigoriev, E.; Hallewell, G.; Han, S.; Hartjes, F.; Hrubec, J.; Husson, D.; Kagan, H.; Kaplon, J.; Kass, R.; Keil, M.; Knoepfle, K.T.; Koeth, T.; Krammer, M.; Logiudice, A.; Lu, R.; Mac Lynne, L.; Manfredotti, C.; Meier, D.; Menichelli, D.; Meuser, S.; Mishina, M.; Moroni, L.; Noomen, J.; Oh, A.; Pernicka, M.; Perera, L.; Potenza, R.; Riester, J.L.; Roe, S.; Rudge, A.; Sala, S.; Sampietro, M.; Schnetzer, S.; Sciortino, S.; Stelzer, H.; Stone, R.; Sutera, C.; Trischuk, W.; Tromson, D.; Tuve, C.; Vincenzo, B.; Weilhammer, P.; Wermes, N.; Wetstein, M.; Zeuner, W.; Zoeller, M.

2004-07-01

Chemical Vapor Deposition (CVD) diamond has been discussed extensively as an alternative sensor material for use very close to the interaction region of the LHC and other machines where extreme radiation conditions exist. During the last seven years the RD42 collaboration has developed diamond detectors and tested them with LHC electronics towards the end of creating a device usable by experiments. The most recent results of this work are presented. Recently, a new form of CVD diamond has been developed: single crystal CVD diamond which resolves many of the issues associated with poly-crystalline CVD material. The first tests of this material are also presented. (orig.)

New developments in CVD diamond for detector applications

International Nuclear Information System (INIS)

Adam, W.; Berdermann, E.; Bergonzo, P.; Brambilla, A.; Boer, W. de; Bogani, F.; Borchi, E.; Bruzzi, M.; Colledani, C.; Dulinski, W.; Conway, J.; Doroshenko, J.; D'Angelo, P.; Furetta, C.; Dabrowski, W.; Delpierre, P.; Fallou, A.; Eijk, B. van; Fischer, P.; Fizzotti, F.; Gan, K.K.; Ghodbane, N.; Grigoriev, E.; Hallewell, G.; Han, S.; Hartjes, F.; Hrubec, J.; Husson, D.; Kagan, H.; Kaplon, J.; Kass, R.; Keil, M.; Knoepfle, K.T.; Koeth, T.; Krammer, M.; Logiudice, A.; Lu, R.; Mac Lynne, L.; Manfredotti, C.; Meier, D.; Menichelli, D.; Meuser, S.; Mishina, M.; Moroni, L.; Noomen, J.; Oh, A.; Pernicka, M.; Perera, L.; Potenza, R.; Riester, J.L.; Roe, S.; Rudge, A.; Sala, S.; Sampietro, M.; Schnetzer, S.; Sciortino, S.; Stelzer, H.; Stone, R.; Sutera, C.; Trischuk, W.; Tromson, D.; Tuve, C.; Vincenzo, B.; Weilhammer, P.; Wermes, N.; Wetstein, M.; Zeuner, W.; Zoeller, M.

2004-01-01

Chemical Vapor Deposition (CVD) diamond has been discussed extensively as an alternative sensor material for use very close to the interaction region of the LHC and other machines where extreme radiation conditions exist. During the last seven years the RD42 collaboration has developed diamond detectors and tested them with LHC electronics towards the end of creating a device usable by experiments. The most recent results of this work are presented. Recently, a new form of CVD diamond has been developed: single crystal CVD diamond which resolves many of the issues associated with poly-crystalline CVD material. The first tests of this material are also presented. (orig.)

Interview with Peter McLaren, on His Work, on His Visit to Turkey and on Ongoing Popular Struggles

Science.gov (United States)

Fassbinder, Samuel Day

2013-01-01

Peter McLaren is, as the back cover of his (2005) Capitalists & Conquerors: a critical pedagogy against empire says, "professor of urban education at the Graduate School of Education and Information Studies at the University of California, Los Angeles". Peter is also now a Distinguished Fellow in Critical Studies at Chapman…

Diamond-based structures to collect and guide light

Energy Technology Data Exchange (ETDEWEB)

Castelletto, S [Centre for Micro-Photonics, Faculty of Engineering and Industrial Sciences, Swinburne University of Technology, Mail H 34 Hawthorn, VIC 3122 (Australia); Harrison, J P; Marseglia, L; Stanley-Clarke, A C; Hadden, J P; Ho, Y-L D; O' Brien, J L; Rarity, J G [Centre for Quantum Photonics, H H Wills Physics Laboratory and Department of Electrical and Electronic Engineering, University of Bristol, Merchant Venturers Building, Woodland Road, Bristol BS8 1UB (United Kingdom); Gibson, B C; Fairchild, B A; Ganesan, K; Huntington, S T; Greentree, A D; Prawer, S [School of Physics, University of Melbourne, Melbourne VIC 3010 (Australia); Hiscocks, M P; Ladouceur, F, E-mail: scastelletto@swin.edu.au, E-mail: luca.marseglia@bristol.ac.uk [School of EE and T, University of New South Wales, Sydney, NSW 2052 (Australia)

2011-02-15

We examine some promising photonic structures for collecting and guiding light in bulk diamond. The aim of this work is to optimize single photon sources and single spin read-out from diamond color centers, specifically NV{sup -} centers. We review the modeling and fabrication (by focused ion beam and reactive ion etching) of solid immersion lenses, waveguides and photonic crystal cavities in monolithic diamond.

Evolution of floral symmetry Peter K Endress, Current Opinion in ...

Indian Academy of Sciences (India)

First page Back Continue Last page Graphics. Evolution of floral symmetry Peter K Endress, Current Opinion in Plant Biology 2001, 4:86–91. Polysymmetric (more than one plane of symmetry) to monosymmetric in angiosperm (flowering plants) evolution; the other way in Antirrhinaceae. Left and right handed helicity. Bees ...

Anmeldelse: Peter Gøtzsches nye bog: Big pharma = Big crime?

DEFF Research Database (Denmark)

Møller, Marianne

2013-01-01

Cochrane-lægen Peter Gøtzsche har udgivet en bog med stærk kritik af medicinalindustrien og systemet for godkendelse og kontrol af medicin. Bogen er ladet med eksempler fra mange terapeutiske områder og er - med sin usædvanligt hårde retorik - en oplagt debatskaber....

Age and growth of the longfin eel, Anguilla mossambica Peters ...

African Journals Online (AJOL)

Otoliths were successfully used for age determination and growth-rate calculation of the longfin eel, Anguilla mossambica Peters, 1852. The large opaque nucleus of the otoliths represents the leptocephalid stage and probably lasts from one and a half to two years. Thereafter, one opaque and one hyaline zone is deposited ...

High speed dry machining of MMCs with diamond tools

International Nuclear Information System (INIS)

Collins, J.L.

2001-01-01

The increasing use of metal matrix composites (MMCs) has raised new issues in their machining. Industrial demands for higher speed and dry machining of MMCs with improved component production to closer tolerances have driven the development of new tool materials. In particular, the wear characteristics of synthetic diamond tooling satisfy many of the requirements imposed in cutting these highly abrasive workpieces. The use of diamond tool materials, such as polycrystalline diamond (PCD), has resulted in tool life improvements which, allied with environmental considerations, show great potential for the development of dry cutting. This paper explores the wear characteristics of PCD, which is highly suited to the dry machining of particulate silicon carbide MMCs. Also, two further diamond tool materials are evaluated - chemical vapor deposition (CVD) thick layer diamond and synthetic single crystal diamond. Their suitability for the efficient machining of high volume fraction MMC materials is shown and their potential impact an the subsequent acceptance and integration of MMCs into engineering components is discussed. (author)

Protein-modified nanocrystalline diamond thin films for biosensor applications.

Science.gov (United States)

Härtl, Andreas; Schmich, Evelyn; Garrido, Jose A; Hernando, Jorge; Catharino, Silvia C R; Walter, Stefan; Feulner, Peter; Kromka, Alexander; Steinmüller, Doris; Stutzmann, Martin

2004-10-01

Diamond exhibits several special properties, for example good biocompatibility and a large electrochemical potential window, that make it particularly suitable for biofunctionalization and biosensing. Here we show that proteins can be attached covalently to nanocrystalline diamond thin films. Moreover, we show that, although the biomolecules are immobilized at the surface, they are still fully functional and active. Hydrogen-terminated nanocrystalline diamond films were modified by using a photochemical process to generate a surface layer of amino groups, to which proteins were covalently attached. We used green fluorescent protein to reveal the successful coupling directly. After functionalization of nanocrystalline diamond electrodes with the enzyme catalase, a direct electron transfer between the enzyme's redox centre and the diamond electrode was detected. Moreover, the modified electrode was found to be sensitive to hydrogen peroxide. Because of its dual role as a substrate for biofunctionalization and as an electrode, nanocrystalline diamond is a very promising candidate for future biosensor applications.

Isotopically pure single crystal epitaxial diamond films and their preparation

International Nuclear Information System (INIS)

Banholzer, W.F.; Anthony, T.R.; Williams, D.M.

1992-01-01

The present invention is directed to the production of single crystal diamond consisting of isotopically pure carbon-12 or carbon-13. In the present invention, isotopically pure single crystal diamond is grown on a single crystal substrate directly from isotopically pure carbon-12 or carbon-13. One method for forming isotopically pure single crystal diamond comprises the steps of placing in a reaction chamber a single substrate heated to an elevated diamond forming temperature. Another method for forming isotopically pure single crystal diamond comprises diffusing isotopically pure carbon-12 or carbon-13 through a metallic catalyst under high pressure to a region containing a single crystal substrate to form an isotopically pure single crystal diamond layer on said single crystal substrate

Theories of Power, Poverty, and Law: In Commemoration of the Contributions of Peter Bachrach--Empowerment and Poverty

Science.gov (United States)

Levi, Margaret

2010-01-01

My subject is the way Peter Bachrach addressed the question of poverty. But given that I was his student and research assistant and that I am a political scientist largely because of him, it is impossible to resist a few words about the experience of being in his classrooms. Peter was an inspiring teacher of politics. The substantive content of…

Optical studies of high quality synthetic diamond

International Nuclear Information System (INIS)

Sharp, S.J.

1999-01-01

This thesis is concerned with the study of fundamental and defect induced optical properties of synthetic diamond grown using high pressure, high temperature (HPHT) synthesis or chemical vapour deposition (CVD). The primary technique used for investigation is cathodoluminescence (including imaging and decay-time measurements) in addition to other forms of optical spectroscopy. This thesis is timely in that the crystallinity and purity of synthetic diamond has increased ten fold over the last few years. The diamond exciton emission, which is easily quenched by the presence of defects, is studied in high quality samples in detail. In addition the ability now exists to engineer the isotopic content of synthetic diamond to a high degree of accuracy. The experimental chapters are divided as follows: Chapter 2: High resolution, low temperature spectra reveal a splitting of the free-exciton phonon recombination emission peaks and the bound-exciton zero phonon line. Included are measurements of the variation in intensity and decay-time as a function of temperature. Chapter 3: The shift in energy of the phonon-assisted free-exciton phonon replicas with isotopic content has been measured. The shift is in agreement with the results of interatomic force model for phonon scattering due to isotope disorder. Chapter 4: A study of the shift in energy with isotopic content of the diamond of the GR1 band due to the neutral vacancy has allowed a verification of the theoretical predictions due to the Jahn Teller effect. Chapter 5: The spatial distribution of the free-exciton luminescence is studied in HPHT synthetic and CVD diamond. A variation in intensity with distance from the surface is interpreted as a significant non-radiative loss of excitons to the surface. Chapter 6: The decay-times of all known self-interstitial related centres have been measured in order to calculate the concentration of these centres present in electron irradiated diamond. (author)

THIN DIAMOND FILMS FOR SNS H INJECTIONS STRIPPING

International Nuclear Information System (INIS)

SHAW, R.W.; HERR, A.D.; FEIGERLE, C.S.; CUTLER, R.J.; LIAW, C.J.; LEE, Y.Y.

2004-01-01

We have investigated the preparation and testing of thin diamond foils for use in stripping the SNS H - Linac beam. A long useful lifetime for these foils is desirable to improve operational efficiency. Preliminary data presented at PAC 2001 indicated that diamond foils were superior to conventional evaporated carbon foils, exhibiting lifetimes approximately five-fold longer [1]. That work employed a fully supported diamond foil, a format that is not acceptable for the SNS application; at least two edges of the approximately 1 x 1 cm foils must be free standing to allow for beam rastering. Residual stress in a chemical vapor deposited (CVD) diamond foil results in film distortion (scrolling) when the film is released from its silicon growth substrate. We have attacked this problem by initially patterning the surface of CVD growth substrates with a 50 or 100 line/inch trapezoidal grating, followed by conformal diamond film growth on the patterned substrate. Then removal of the substrate by chemical etching produced a foil that possessed improved mechanical integrity due to its corrugation. The high nucleation density required to grow continuous, pinhole free diamond foils of the desired thickness (1 (micro)m, 350 (micro)g/cm 2 ) was achieved by a combination of substrate surface scratching and seeding. A variety of diamond foils have been tested using the BNL 750 keV Radio Frequency Quadrupole H - beam to simulate energy loss in the SNS. Those include flat, corrugated, microcrystalline, and nanocrystalline foils. Foil lifetimes are reported

Nucleation mechanism for the direct graphite-to-diamond phase transition

Science.gov (United States)

Khaliullin, Rustam Z.; Eshet, Hagai; Kühne, Thomas D.; Behler, Jörg; Parrinello, Michele

2011-09-01

Graphite and diamond have comparable free energies, yet forming diamond from graphite in the absence of a catalyst requires pressures that are significantly higher than those at equilibrium coexistence. At lower temperatures, the formation of the metastable hexagonal polymorph of diamond is favoured instead of the more stable cubic diamond. These phenomena cannot be explained by the concerted mechanism suggested in previous theoretical studies. Using an ab initio quality neural-network potential, we carried out a large-scale study of the graphite-to-diamond transition assuming that it occurs through nucleation. The nucleation mechanism accounts for the observed phenomenology and reveals its microscopic origins. We demonstrate that the large lattice distortions that accompany the formation of diamond nuclei inhibit the phase transition at low pressure, and direct it towards the hexagonal diamond phase at higher pressure. The proposed nucleation mechanism should improve our understanding of structural transformations in a wide range of carbon-based materials.

ROLE OF DIAMOND SECONDARY EMITTERS IN HIGH BRIGHTNESS ELECTRON SOURCES

International Nuclear Information System (INIS)

2005-01-01

In this paper we explore the possibility of using diamond secondary emitter in a high average current electron injector to amplify the current from the photocathode and to isolate the cathode and the injector from each other to increase the life time of the cathode and preserve the performance of the injector. Secondary electron yield of 225 and current density of 0.8 a/cm 2 have been measured in the transmission mode from type 2 a natural diamond. Although the diamond will be heated during normal operation in the injector, calculations indicate that by cryogenically cooling the diamond, the temperature gradient along the diamond can be maintained within the acceptable range. The electron energy and temporal distributions are expected to be narrow from this device resulting in high brightness beams. Plans are underway to measure the SEY in emission mode, fabricate photocathode-diamond capsule and test diamond and capsule in superconducting RF injector

High pressure sintering (HP-HT) of diamond powders with titanium and titanium carbide

International Nuclear Information System (INIS)

Jaworska, L.

1999-01-01

Polycrystalline diamond compacts for cutting tools are mostly manufactured using high pressure sintering (HP-HT). The standard diamond compacts are prepared by diamond powders sintering with metallic binding phase. The first group of metallic binder are metals able to solve carbon - Co, Ni. The second group of metal binders are carbide forming elements - Ti, Cr, W and others. The paper describes high pressure sintering of diamond powder with titanium and nonstoichiometry titanium carbide for cutting tool application. A type of binding phase has the significant influence on microstructure and mechanical properties of diamond compacts. Very homogeneous structure was achieved in case of compacts obtained from metalized diamond where diamond-TiC-diamond connection were predominant. In the case of compacts prepared by mechanical mixing of diamond with titanium powders the obtained structure was nonhomogeneous with titanium carbide clusters. They had more diamond to diamond connections. These compacts compared to the compact made of metallized diamond have greater wear resistance. In the case of the diamond and TiC 0.92 sintering the strong bonding of TiC diamond grains was obtained. The microstructure observations for diamond with 5% wt. Ti and diamond with 5% wt. TiC 0.92 (the initial composition) compacts were performed in transmission microscope. For two type of compacts the strong bonding phase TiC without defects is creating. (author)

An electrical conductivity inspection methodology of polycrystalline diamond cutters

Science.gov (United States)

Bogdanov, G.; Wiggins, J.; Bertagnolli, K.; Ludwig, R.

2012-05-01

The polycrystalline diamond cutter (PDC) is widely used in oil and gas drilling operations. It is manufactured by sintering diamond powder onto a tungsten carbide substrate at 6 GPa and 1500 C. During sintering, molten cobalt from the substrate infiltrates the diamond table. The residual metal content correlates with cutter performance. We present an instrument that employs electrical impedance tomography capable of imaging the 3D metal content distribution in the diamond table. These images can be used to predict cutter performance as well as detect flaws.

Eclogitic inclusions in diamonds: Evidence of complex mantle processes over time

Science.gov (United States)

Taylor, Lawrence A.; Snyder, Gregory A.; Crozaz, Ghislaine; Sobolev, Vladimir N.; Yefimova, Emiliya S.; Sobolev, Nikolai V.

1996-08-01

The first ion-probe trace element analyses of clinopyroxene-garnet pairs both included within diamonds and from the eclogite host xenoliths are reported; these diamondiferous eclogites are from the Udachnaya and Mir kimberlite pipes, Yakutia, Russia. The major and trace element analyses of these diamond-inclusion and host-rock pairs are compared in order to determine the relative ages of the diamonds, confirm or deny genetic relationships between the diamonds and the eclogites, evaluate models of eclogite petrogenesis, and model igneous processes in the mantle before, during, and after diamond formation. The most striking aspect of the chemical compositions of the diamond inclusions is the diversity of relationships with their eclogite hosts. No single distinct pattern of variation from diamond inclusion minerals to host minerals is found for all four samples. Garnet and clinopyroxene inclusions in the diamonds from two samples (U-65/3 and U-66/3) have lower Mg#s, lower Mg, and higher Fe contents, and lower LREE than those in the host eclogite. We interpret such variations as due to metasomatism of the host eclogite after diamond formation. One sample, U-41/3 shows enrichment in diamond-inclusion MREE enrichment relative to the eclogite host and may indicate a metasomatic event prior to, or during, diamond formation. Bulanova [2] found striking differences between inclusions taken from within different portions of the very same diamond. Clinopyroxene inclusions taken from the central (early) portions of Yakutian diamonds were lower in Mg# and Mg contents (by up to 25%) than those later inclusions at the rims of diamonds. These trends are parallel to those between diamond inclusions and host eclogites determined for four of the five samples from the present study and may merely represent changing magmatic and/or P-T conditions in the mantle. Garnet trace element compositions are similar in relative proportions, but variable in abundances, between diamond inclusions

Synthesis of silicon carbide coating on diamond by microwave heating of diamond and silicon powder: A heteroepitaxial growth

Energy Technology Data Exchange (ETDEWEB)

Leparoux, S. [Empa, Department of Materials Technology, Feuerwerkerstrasse 39, CH-3602 Thun (Switzerland)], E-mail: susanne.leparoux@empa.ch; Diot, C. [Consultant, allee de Mozart 10, F-92300 Chatillon (France); Dubach, A. [Empa, Department of Materials Technology, Feuerwerkerstrasse 39, CH-3602 Thun (Switzerland); Vaucher, S. [Empa, Department of Materials Technology, Feuerwerkerstrasse 39, CH-3602 Thun (Switzerland)

2007-10-15

When a powder mixture of diamond and silicon is heated by microwaves, heteroepitaxial growth of SiC is observed on the (1 1 1) as well as on the (1 0 0) faces of the diamond. The SiC over-layer was characterized by X-ray diffraction and scanning electron microscopy. High-resolution scanning electron microscopy shows the presence of triangular silicon carbide on the (1 1 1) faces of diamond while prismatic crystals are found on the (1 0 0) faces. The crystal growth seems to be favored in the plane parallel to the face (1 1 1)

Synthesis of silicon carbide coating on diamond by microwave heating of diamond and silicon powder: A heteroepitaxial growth

International Nuclear Information System (INIS)

Leparoux, S.; Diot, C.; Dubach, A.; Vaucher, S.

2007-01-01

When a powder mixture of diamond and silicon is heated by microwaves, heteroepitaxial growth of SiC is observed on the (1 1 1) as well as on the (1 0 0) faces of the diamond. The SiC over-layer was characterized by X-ray diffraction and scanning electron microscopy. High-resolution scanning electron microscopy shows the presence of triangular silicon carbide on the (1 1 1) faces of diamond while prismatic crystals are found on the (1 0 0) faces. The crystal growth seems to be favored in the plane parallel to the face (1 1 1)

New species of Temnocephala Blanchard (Platyhelminthes, Temnocephalida ectosymbiont on giant water bugs, Belostoma spp. (Hemiptera, Belostomatidae from southern Brazil Nova espécie do gênero Temnocephala Blanchard (Platyhelminthes, Temnocephalida ectosimbionte sobre baratas d´água, Belostoma spp. (Hemiptera, Belostomatidae da região sul do Brasil

Directory of Open Access Journals (Sweden)

José F. R. Amato

2005-03-01

Full Text Available A new species of Temnocephala Blanchard, 1849 is described from southern Brazil, ectosymbiont on giant water bugs (aquatic hemipterans, Belostoma spp. from the greater Porto Alegre, State of Rio Grande do Sul. Some hemipterans examined were positive for this species of Temnocephala and carried bunches of eggs between the first two pairs of legs and between the first pair of legs and the rostrum, as well as adult and young specimens. The adults were darkly pigmented (greenish-brown, mimetizing the color of the hemipteran hosts. The new species is similar to Temnocephala decarloi Moretto, 1978, from Argentina, the only other species of Temnocephala from belostomatid hemipterans known to date, by having an extra long and curved cirrus, but differs by having the distal portion of the introvert not bent as a 'full-bent' smoking pipe-like, as the author depicted originally for T. decarloi.Uma nova espécie de Temnocephala Blanchard, 1849 é descrita para o sul do Brasil, ectosimbionte sobre baratas-d'água (hemípteros aquáticos, Belostoma spp. da região metropolitana de Porto Alegre, Estado do Rio Grande do Sul. Vários hemípteros examinados estavam positivos para esta espécie do gênero Temnocephala, inclusive com posturas sempre localizadas na face ventral entre os dois primeiros pares de apêndices locomotores, e entre o primeiro par de pernas e o rostro. Espécimes adultos e jovens de tamanhos variados também foram sempre encontrados na face ventral do hemíptero. Os vermes adultos eram pigmentados (marrom-esverdeado, mimetizando a cor do exoesqueleto de seus hospedeiros. A nova espécie é semelhante à Temnocephala decarloi Moretto, 1978, descrita da Argentina, única espécie conhecida do gênero já encontrada sobre hemípteros belostomatídeos, por ter um cirro extremamente longo e curvo, mas difere desta por ter a porção distal do 'introvert' sem a forma típica de um cachimbo ('full-bent' como ilustrada pelo autor na descri

Micro-strip sensors based on CVD diamond

Energy Technology Data Exchange (ETDEWEB)

Adam, W.; Berdermann, E.; Bergonzo, P.; Bertuccio, G.; Bogani, F.; Borchi, E.; Brambilla, A.; Bruzzi, M.; Colledani, C.; Conway, J.; D' Angelo, P.; Dabrowski, W.; Delpierre, P.; Deneuville, A.; Dulinski, W.; Eijk, B. van; Fallou, A.; Fizzotti, F.; Foulon, F.; Friedl, M.; Gan, K.K.; Gheeraert, E.; Hallewell, G.; Han, S.; Hartjes, F.; Hrubec, J.; Husson, D.; Kagan, H.; Kania, D.; Kaplon, J.; Kass, R.; Koeth, T.; Krammer, M.; Logiudice, A.; Lu, R.; Mac Lynne, L.; Manfredotti, C.; Meier, D. E-mail: dirk.meier@cern.ch; Mishina, M.; Moroni, L.; Oh, A.; Pan, L.S.; Pernicka, M.; Peitz, A.; Perera, L.; Pirollo, S.; Procario, M.; Riester, J.L.; Roe, S.; Rousseau, L.; Rudge, A.; Russ, J.; Sala, S.; Sampietro, M.; Schnetzer, S.; Sciortino, S.; Stelzer, H.; Stone, R.; Suter, B.; Tapper, R.J.; Tesarek, R.; Trischuk, W.; Tromson, D.; Vittone, E.; Walsh, A.M.; Wedenig, R.; Weilhammer, P.; Wetstein, M.; White, C.; Zeuner, W.; Zoeller, M

2000-10-11

In this article we present the performance of recent chemical vapour deposition (CVD) diamond micro-strip sensors in beam tests. In addition, we present the first comparison of a CVD diamond micro-strip sensor before and after proton irradiation.

Micro-strip sensors based on CVD Diamond

CERN Document Server

Adam, W; Bergonzo, P; Bertuccio, G; Bogani, F; Borchi, E; Brambilla, A; Bruzzi, Mara; Colledani, C; Conway, J; D'Angelo, P; Dabrowski, W; Delpierre, P A; Deneuville, A; Dulinski, W; van Eijk, B; Fallou, A; Fizzotti, F; Foulon, F; Friedl, M; Gan, K K; Gheeraert, E; Hallewell, G D; Han, S; Hartjes, F G; Hrubec, Josef; Husson, D; Kagan, H; Kania, D R; Kaplon, J; Kass, R; Koeth, T W; Krammer, Manfred; Lo Giudice, A; Lü, R; MacLynne, L; Manfredotti, C; Meier, D; Mishina, M; Moroni, L; Oh, A; Pan, L S; Pernicka, Manfred; Peitz, A; Perera, L P; Pirollo, S; Procario, M; Riester, J L; Roe, S; Rousseau, L; Rudge, A; Russ, J; Sala, S; Sampietro, M; Schnetzer, S R; Sciortino, S; Stelzer, H; Stone, R; Suter, B; Tapper, R J; Tesarek, R J; Trischuk, W; Tromson, D; Vittone, E; Walsh, A M; Wedenig, R; Weilhammer, Peter; Wetstein, M; White, C; Zeuner, W; Zoeller, M M

2000-01-01

In this article we present the performance of recent chemical vapour deposition (CVD) diamond micro-strip sensors in beam tests. In addition we present the first comparison of a CVD diamond micro-strip sensor before and after proton irradiation.

Micro-strip sensors based on CVD diamond

International Nuclear Information System (INIS)

Adam, W.; Berdermann, E.; Bergonzo, P.; Bertuccio, G.; Bogani, F.; Borchi, E.; Brambilla, A.; Bruzzi, M.; Colledani, C.; Conway, J.; D'Angelo, P.; Dabrowski, W.; Delpierre, P.; Deneuville, A.; Dulinski, W.; Eijk, B. van; Fallou, A.; Fizzotti, F.; Foulon, F.; Friedl, M.; Gan, K.K.; Gheeraert, E.; Hallewell, G.; Han, S.; Hartjes, F.; Hrubec, J.; Husson, D.; Kagan, H.; Kania, D.; Kaplon, J.; Kass, R.; Koeth, T.; Krammer, M.; Logiudice, A.; Lu, R.; Mac Lynne, L.; Manfredotti, C.; Meier, D.; Mishina, M.; Moroni, L.; Oh, A.; Pan, L.S.; Pernicka, M.; Peitz, A.; Perera, L.; Pirollo, S.; Procario, M.; Riester, J.L.; Roe, S.; Rousseau, L.; Rudge, A.; Russ, J.; Sala, S.; Sampietro, M.; Schnetzer, S.; Sciortino, S.; Stelzer, H.; Stone, R.; Suter, B.; Tapper, R.J.; Tesarek, R.; Trischuk, W.; Tromson, D.; Vittone, E.; Walsh, A.M.; Wedenig, R.; Weilhammer, P.; Wetstein, M.; White, C.; Zeuner, W.; Zoeller, M.

2000-01-01

In this article we present the performance of recent chemical vapour deposition (CVD) diamond micro-strip sensors in beam tests. In addition, we present the first comparison of a CVD diamond micro-strip sensor before and after proton irradiation

Micro-strip sensors based on CVD diamond

Science.gov (United States)

Adam, W.; Berdermann, E.; Bergonzo, P.; Bertuccio, G.; Bogani, F.; Borchi, E.; Brambilla, A.; Bruzzi, M.; Colledani, C.; Conway, J.; D'Angelo, P.; Dabrowski, W.; Delpierre, P.; Deneuville, A.; Dulinski, W.; van Eijk, B.; Fallou, A.; Fizzotti, F.; Foulon, F.; Friedl, M.; Gan, K. K.; Gheeraert, E.; Hallewell, G.; Han, S.; Hartjes, F.; Hrubec, J.; Husson, D.; Kagan, H.; Kania, D.; Kaplon, J.; Kass, R.; Koeth, T.; Krammer, M.; Logiudice, A.; Lu, R.; mac Lynne, L.; Manfredotti, C.; Meier, D.; Mishina, M.; Moroni, L.; Oh, A.; Pan, L. S.; Pernicka, M.; Peitz, A.; Perera, L.; Pirollo, S.; Procario, M.; Riester, J. L.; Roe, S.; Rousseau, L.; Rudge, A.; Russ, J.; Sala, S.; Sampietro, M.; Schnetzer, S.; Sciortino, S.; Stelzer, H.; Stone, R.; Suter, B.; Tapper, R. J.; Tesarek, R.; Trischuk, W.; Tromson, D.; Vittone, E.; Walsh, A. M.; Wedenig, R.; Weilhammer, P.; Wetstein, M.; White, C.; Zeuner, W.; Zoeller, M.; RD42 Collaboration

2000-10-01

In this article we present the performance of recent chemical vapour deposition (CVD) diamond micro-strip sensors in beam tests. In addition, we present the first comparison of a CVD diamond micro-strip sensor before and after proton irradiation.

Rhenium Alloys as Ductile Substrates for Diamond Thin-Film Electrodes.

Science.gov (United States)

Halpern, Jeffrey M; Martin, Heidi B

2014-02-01

Molybdenum-rhenium (Mo/Re) and tungsten-rhenium (W/Re) alloys were investigated as substrates for thin-film, polycrystalline boron-doped diamond electrodes. Traditional, carbide-forming metal substrates adhere strongly to diamond but lose their ductility during exposure to the high-temperature (1000°C) diamond, chemical vapor deposition environment. Boron-doped semi-metallic diamond was selectively deposited for up to 20 hours on one end of Mo/Re (47.5/52.5 wt.%) and W/Re (75/25 wt.%) alloy wires. Conformal diamond films on the alloys displayed grain sizes and Raman signatures similar to films grown on tungsten; in all cases, the morphology and Raman spectra were consistent with well-faceted, microcrystalline diamond with minimal sp 2 carbon content. Cyclic voltammograms of dopamine in phosphate-buffered saline (PBS) showed the wide window and low baseline current of high-quality diamond electrodes. In addition, the films showed consistently well-defined, dopamine electrochemical redox activity. The Mo/Re substrate regions that were uncoated but still exposed to the diamond-growth environment remained substantially more flexible than tungsten in a bend-to-fracture rotation test, bending to the test maximum of 90° and not fracturing. The W/Re substrates fractured after a 27° bend, and the tungsten fractured after a 21° bend. Brittle, transgranular cleavage fracture surfaces were observed for tungsten and W/Re. A tension-induced fracture of the Mo/Re after the prior bend test showed a dimple fracture with a visible ductile core. Overall, the Mo/Re and W/Re alloys were suitable substrates for diamond growth. The Mo/Re alloy remained significantly more ductile than traditional tungsten substrates after diamond growth, and thus may be an attractive metal substrate for more ductile, thin-film diamond electrodes.

Signaling Pathways in Pathogenesis of Diamond Blackfan Anemia

Science.gov (United States)

2015-12-01

AWARD NUMBER: W81XWH-12-1-0590 TITLE: SIGNALING PATHWAYS IN PATHOGENESIS OF DIAMOND BLACKFAN ANEMIA PRINCIPAL INVESTIGATOR: KATHLEEN M...SUBTITLE 5a. CONTRACT NUMBER W81XWH-12-1-0590 SIGNALING PATHWAYS IN PATHOGENESIS OF DIAMOND BLACKFAN ANEMIA 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER...Unlimited 13. SUPPLEMENTARY NOTES None 14. ABSTRACT: Diamond Blackfan Anemia (DBA) is a disorder that results in pure red cell aplasia, congenital

Voltammetric and impedance behaviours of surface-treated nano-crystalline diamond film electrodes

International Nuclear Information System (INIS)

Liu, F. B.; Jing, B.; Cui, Y.; Di, J. J.; Qu, M.

2015-01-01

The electrochemical performances of hydrogen- and oxygen-terminated nano-crystalline diamond film electrodes were investigated by cyclic voltammetry and AC impedance spectroscopy. In addition, the surface morphologies, phase structures, and chemical states of the two diamond films were analysed by scanning probe microscopy, Raman spectroscopy, and X-ray photoelectron spectroscopy, respectively. The results indicated that the potential window is narrower for the hydrogen-terminated nano-crystalline diamond film than for the oxygen-terminated one. The diamond film resistance and capacitance of oxygen-terminated diamond film are much larger than those of the hydrogen-terminated diamond film, and the polarization resistances and double-layer capacitance corresponding to oxygen-terminated diamond film are both one order of magnitude larger than those corresponding to the hydrogen-terminated diamond film. The electrochemical behaviours of the two diamond film electrodes are discussed

Geochemistry of single diamond crystals by instrumental neutron activation analysis

International Nuclear Information System (INIS)

Damarupurshad, A.

1995-02-01

Neutron activation analysis is probably the most powerful technique, available to date, for the analysis of the trace elements in diamond. In this study the technique of neutron activation analysis has been modified and optimized for the analysis of single, small (0.01-0.5 carat), inclusion-bearing and inclusion-free diamonds. Instrumental neutron activation analysis was used to analyze for up to 40 different elements at the ppb and ppt levels in diamonds from Brazil, South Africa, Colorado and China. The data obtained was used to detect and understand the differences between diamonds from the eclogitic and peridotitic para geneses and between diamonds from the different localities. In this regard, two inter element ratios, i.e. Cr/Sc and Au/Ir ratios were found to be useful. It seems that diamonds from a particular locality or mine have a unique range of Cr/Sc ratios. Furthermore, the identity of the dominant silicate inclusion(s) can be deduced from the Cr/Sc ratio of the diamond, since each type of silicate inclusion has a different range of Cr/Sc ratios. Not only is the Cr/Sc ratio distinctive for silicate inclusions in diamonds, it is also distinctive for minerals co genetic with diamond, such as orange garnet, red garnet, chrome diopside and ortho pyroxene (macrocrysts) which were separated from kimberlites. Sulphide inclusions may also contain detectable quantities of Au and Ir and the ratios of these two elements can also be used to differentiate between diamonds of the two para geneses. Carbon isotope ratios of these eclogitic and peridotitic diamonds were also measured. The comparison of this with the Cr/Sc ratios revealed that the carbon isotope ratios of both para geneses overlap in a narrow range and do not show the clear separations seen with Cr/Sc and Au/Ir ratios. It can be suggested, therefore, on the basis of the suite of 61 diamonds analyzed in this study, that the Cr/Sc and Au/Ir ratios are much more useful tools to distinguish between diamonds

CVD diamond pixel detectors for LHC experiments

Energy Technology Data Exchange (ETDEWEB)

Wedenig, R.; Adam, W.; Bauer, C.; Berdermann, E.; Bergonzo, P.; Bogani, F.; Borchi, E.; Brambilla, A.; Bruzzi, M.; Colledani, C.; Conway, J.; Dabrowski, W.; Delpierre, P.; Deneuville, A.; Dulinski, W.; Eijk, B. van; Fallou, A.; Fizzotti, F.; Foulon, F.; Friedl, M.; Gan, K.K.; Gheeraert, E.; Grigoriev, E.; Hallewell, G.; Hall-Wilton, R.; Han, S.; Hartjes, F.; Hrubec, J.; Husson, D.; Kagan, H.; Kania, D.; Kaplon, J.; Karl, C.; Kass, R.; Knoepfle, K.T.; Krammer, M.; Logiudice, A.; Lu, R.; Manfredi, P.F.; Manfredotti, C.; Marshall, R.D.; Meier, D.; Mishina, M.; Oh, A.; Pan, L.S.; Palmieri, V.G.; Pernicka, M.; Peitz, A.; Pirollo, S.; Polesello, P.; Pretzl, K.; Procario, M.; Re, V.; Riester, J.L.; Roe, S.; Roff, D.; Rudge, A.; Runolfsson, O.; Russ, J.; Schnetzer, S.; Sciortino, S.; Speziali, V.; Stelzer, H.; Stone, R.; Suter, B.; Tapper, R.J.; Tesarek, R.; Trawick, M.; Trischuk, W.; Vittone, E.; Wagner, A.; Walsh, A.M.; Weilhammer, P.; White, C.; Zeuner, W.; Ziock, H.; Zoeller, M.; Blanquart, L.; Breugnion, P.; Charles, E.; Ciocio, A.; Clemens, J.C.; Dao, K.; Einsweiler, K.; Fasching, D.; Fischer, P.; Joshi, A.; Keil, M.; Klasen, V.; Kleinfelder, S.; Laugier, D.; Meuser, S.; Milgrome, O.; Mouthuy, T.; Richardson, J.; Sinervo, P.; Treis, J.; Wermes, N

1999-08-01

This paper reviews the development of CVD diamond pixel detectors. The preparation of the diamond pixel sensors for bump-bonding to the pixel readout electronics for the LHC and the results from beam tests carried out at CERN are described.

CVD diamond pixel detectors for LHC experiments

International Nuclear Information System (INIS)

Wedenig, R.; Adam, W.; Bauer, C.; Berdermann, E.; Bergonzo, P.; Bogani, F.; Borchi, E.; Brambilla, A.; Bruzzi, M.; Colledani, C.; Conway, J.; Dabrowski, W.; Delpierre, P.; Deneuville, A.; Dulinski, W.; Eijk, B. van; Fallou, A.; Fizzotti, F.; Foulon, F.; Friedl, M.; Gan, K.K.; Gheeraert, E.; Grigoriev, E.; Hallewell, G.; Hall-Wilton, R.; Han, S.; Hartjes, F.; Hrubec, J.; Husson, D.; Kagan, H.; Kania, D.; Kaplon, J.; Karl, C.; Kass, R.; Knoepfle, K.T.; Krammer, M.; Logiudice, A.; Lu, R.; Manfredi, P.F.; Manfredotti, C.; Marshall, R.D.; Meier, D.; Mishina, M.; Oh, A.; Pan, L.S.; Palmieri, V.G.; Pernicka, M.; Peitz, A.; Pirollo, S.; Polesello, P.; Pretzl, K.; Procario, M.; Re, V.; Riester, J.L.; Roe, S.; Roff, D.; Rudge, A.; Runolfsson, O.; Russ, J.; Schnetzer, S.; Sciortino, S.; Speziali, V.; Stelzer, H.; Stone, R.; Suter, B.; Tapper, R.J.; Tesarek, R.; Trawick, M.; Trischuk, W.; Vittone, E.; Wagner, A.; Walsh, A.M.; Weilhammer, P.; White, C.; Zeuner, W.; Ziock, H.; Zoeller, M.; Blanquart, L.; Breugnion, P.; Charles, E.; Ciocio, A.; Clemens, J.C.; Dao, K.; Einsweiler, K.; Fasching, D.; Fischer, P.; Joshi, A.; Keil, M.; Klasen, V.; Kleinfelder, S.; Laugier, D.; Meuser, S.; Milgrome, O.; Mouthuy, T.; Richardson, J.; Sinervo, P.; Treis, J.; Wermes, N.

1999-01-01

This paper reviews the development of CVD diamond pixel detectors. The preparation of the diamond pixel sensors for bump-bonding to the pixel readout electronics for the LHC and the results from beam tests carried out at CERN are described

Investigation of defects in CVD diamond: Influence for radiotherapy applications

International Nuclear Information System (INIS)

Guerrero, M.J.; Tromson, D.; Bergonzo, P.; Barrett, R.

2005-01-01

In this study we present the potentialities of CVD diamond as an ionisation chamber for radiotherapy applications. Trapping levels present in CVD diamond are characterised using Thermally Stimulated Current (TSC) method with X-ray sources. The influence of the corresponding defects on the detector response is investigated and compared to those observed in natural diamond. Also, their spatial distribution across a large area polycrystalline diamond ionisation chamber is discussed. Results show the relative influence of two different populations of trapping levels in CVD diamond whose effect is crucial for radiotherapy applications. To partially overcome the defect detrimental effects, we propose to use CVD diamond ionisation chambers at moderate temperatures from 70 to 100 deg. C that could be provided by self heating of the device, for a dramatically improved stability and reproducibility

Substitutional Nitrogen in Nanodiamond and Bucky-Diamond Particles

Energy Technology Data Exchange (ETDEWEB)

Barnard, Amanda S.; Sternberg, Michael G.

2005-09-15

The inclusion of dopants (such as nitrogen) in diamond nanoparticles is expected to be important for use in future nanodevices, such as qubits for quantum computing. Although most commercial diamond nanoparticles contain a small fraction of nitrogen, it is still unclear whether it is located within the core or at the surface of the nanoparticle. Presented here are density functional tight binding simulations examining the configuration, potential energy surface, and electronic charge of substitutional nitrogen in nanodiamond and bucky-diamond particles. The results predict that nitrogen is likely to be positioned at the surface of both hydrogenated nanodiamond and (dehydrogenated) bucky-diamond, and that the coordination of the dopants within the particles is dependent upon the surface structure.

Stress analysis of CVD diamond window for ECH system

International Nuclear Information System (INIS)

Takahashi, Koji

2001-03-01

The stress analysis of a chemical vapor deposition (CVD) diamond window for Electron Cyclotron Heating and Current Drive (ECH/ECCD) system of fusion reactors is described. It was found that the real size diamond window (φ aper =70mm, t=2.25mm) withstood 14.5 atm. (1.45 MPa). The calculation results of the diamond window by ABAQUS code agree well with the results of the pressure test. The design parameters of the torus diamond window for a vacuum and a safety barrier were also obtained. (author)

The development of diamond tracking detectors for the LHC

International Nuclear Information System (INIS)

Adam, W.; Berdermann, E.; Bergonzo, P.; Boer, W. de; Bogani, F.; Borchi, E.; Brambilla, A.; Bruzzi, M.; Colledani, C.; Conway, J.; D'Angelo, P.; Dabrowski, W.; Delpierre, P.; Doroshenko, J.; Dulinski, W.; Eijk, B. van; Fallou, A.; Fischer, P.; Fizzotti, F.; Furetta, C.; Gan, K.K.; Ghodbane, N.; Grigoriev, E.; Hallewell, G.; Han, S.; Hartjes, F.; Hrubec, J.; Husson, D.; Kagan, H.; Kaplon, J.; Karl, C.; Kass, R.; Keil, M.; Knoepfle, K.T.; Koeth, T.; Krammer, M.; Logiudice, A.; Lu, R.; Mac Lynne, L.; Manfredotti, C.; Marshall, R.D.; Meier, D.; Menichelli, D.; Meuser, S.; Mishina, M.; Moroni, L.; Noomen, J.; Oh, A.; Perera, L.; Pernegger, H.; Pernicka, M.; Polesello, P.; Potenza, R.; Riester, J.L.; Roe, S.; Rudge, A.; Sala, S.; Sampietro, M.; Schnetzer, S.; Sciortino, S.; Stelzer, H.; Stone, R.; Sutera, C.; Trischuk, W.; Tromson, D.; Tuve, C.; Vincenzo, B.; Weilhammer, P.; Wermes, N.; Wetstein, M.; Zeuner, W.; Zoeller, M.

2003-01-01

Chemical vapor deposition diamond has been discussed extensively as an alternate sensor material for use very close to the interaction region of the LHC where extreme radiation conditions exist. During the last few years diamond devices have been manufactured and tested with LHC electronics with the goal of creating a detector usable by all LHC experiment. Extensive progress on diamond quality, on the development of diamond trackers and on radiation hardness studies has been made. Transforming the technology to the LHC specific requirements is now underway. In this paper we present the recent progress achieved

The development of diamond tracking detectors for the LHC

CERN Document Server

Adam, W; Bergonzo, P; de Boer, Wim; Bogani, F; Borchi, E; Brambilla, A; Bruzzi, M; Colledani, C; Conway, J; D'Angelo, P; Dabrowski, W; Delpierre, P A; Doroshenko, J; Dulinski, W; van Eijk, B; Fallou, A; Fischer, P; Fizzotti, F; Furetta, C; Gan, K K; Ghodbane, N; Grigoriev, E; Hallewell, G D; Han, S; Hartjes, F; Hrubec, Josef; Husson, D; Kagan, H; Kaplon, J; Karl, C; Kass, R; Keil, M; Knöpfle, K T; Koeth, T W; Krammer, M; Lo Giudice, A; Lü, R; MacLynne, L; Manfredotti, C; Marshall, R D; Meier, D; Menichelli, D; Meuser, S; Mishina, M; Moroni, L; Noomen, J; Oh, A; Perera, L; Pernegger, H; Pernicka, M; Polesello, P; Potenza, R; Riester, J L; Roe, S; Rudge, A; Sala, S; Sampietro, M; Schnetzer, S; Sciortino, S; Stelzer, H; Stone, R; Sutera, C; Trischuk, W; Tromson, D; Tuvé, C; Vincenzo, B; Weilhammer, P; Wermes, N; Wetstein, M; Zeuner, W; Zöller, M

2003-01-01

Chemical vapor deposition diamond has been discussed extensively as an alternate sensor material for use very close to the interaction region of the LHC where extreme radiation conditions exist. During the last few years diamond devices have been manufactured and tested with LHC electronics with the goal of creating a detector usable by all LHC experiment. Extensive progress on diamond quality, on the development of diamond trackers and on radiation hardness studies has been made. Transforming the technology to the LHC specific requirements is now underway. In this paper we present the recent progress achieved.

The development of diamond tracking detectors for the LHC

Energy Technology Data Exchange (ETDEWEB)

Adam, W.; Berdermann, E.; Bergonzo, P.; Boer, W. de; Bogani, F.; Borchi, E.; Brambilla, A.; Bruzzi, M.; Colledani, C.; Conway, J.; D' Angelo, P.; Dabrowski, W.; Delpierre, P.; Doroshenko, J.; Dulinski, W.; Eijk, B. van; Fallou, A.; Fischer, P.; Fizzotti, F.; Furetta, C.; Gan, K.K.; Ghodbane, N.; Grigoriev, E.; Hallewell, G.; Han, S.; Hartjes, F.; Hrubec, J.; Husson, D.; Kagan, H. E-mail: harris.kagan@cern.ch; Kaplon, J.; Karl, C.; Kass, R.; Keil, M.; Knoepfle, K.T.; Koeth, T.; Krammer, M.; Logiudice, A.; Lu, R.; Mac Lynne, L.; Manfredotti, C.; Marshall, R.D.; Meier, D.; Menichelli, D.; Meuser, S.; Mishina, M.; Moroni, L.; Noomen, J.; Oh, A.; Perera, L.; Pernegger, H.; Pernicka, M.; Polesello, P.; Potenza, R.; Riester, J.L.; Roe, S.; Rudge, A.; Sala, S.; Sampietro, M.; Schnetzer, S.; Sciortino, S.; Stelzer, H.; Stone, R.; Sutera, C.; Trischuk, W.; Tromson, D.; Tuve, C.; Vincenzo, B.; Weilhammer, P.; Wermes, N.; Wetstein, M.; Zeuner, W.; Zoeller, M

2003-11-21

Chemical vapor deposition diamond has been discussed extensively as an alternate sensor material for use very close to the interaction region of the LHC where extreme radiation conditions exist. During the last few years diamond devices have been manufactured and tested with LHC electronics with the goal of creating a detector usable by all LHC experiment. Extensive progress on diamond quality, on the development of diamond trackers and on radiation hardness studies has been made. Transforming the technology to the LHC specific requirements is now underway. In this paper we present the recent progress achieved.

The development of diamond tracking detectors for the LHC

Science.gov (United States)

Adam, W.; Berdermann, E.; Bergonzo, P.; de Boer, W.; Bogani, F.; Borchi, E.; Brambilla, A.; Bruzzi, M.; Colledani, C.; Conway, J.; D'Angelo, P.; Dabrowski, W.; Delpierre, P.; Doroshenko, J.; Dulinski, W.; van Eijk, B.; Fallou, A.; Fischer, P.; Fizzotti, F.; Furetta, C.; Gan, K. K.; Ghodbane, N.; Grigoriev, E.; Hallewell, G.; Han, S.; Hartjes, F.; Hrubec, J.; Husson, D.; Kagan, H.; Kaplon, J.; Karl, C.; Kass, R.; Keil, M.; Knöpfle, K. T.; Koeth, T.; Krammer, M.; Logiudice, A.; Lu, R.; mac Lynne, L.; Manfredotti, C.; Marshall, R. D.; Meier, D.; Menichelli, D.; Meuser, S.; Mishina, M.; Moroni, L.; Noomen, J.; Oh, A.; Perera, L.; Pernegger, H.; Pernicka, M.; Polesello, P.; Potenza, R.; Riester, J. L.; Roe, S.; Rudge, A.; Sala, S.; Sampietro, M.; Schnetzer, S.; Sciortino, S.; Stelzer, H.; Stone, R.; Sutera, C.; Trischuk, W.; Tromson, D.; Tuve, C.; Vincenzo, B.; Weilhammer, P.; Wermes, N.; Wetstein, M.; Zeuner, W.; Zoeller, M.; RD42 Collaboration

2003-11-01

Chemical vapor deposition diamond has been discussed extensively as an alternate sensor material for use very close to the interaction region of the LHC where extreme radiation conditions exist. During the last few years diamond devices have been manufactured and tested with LHC electronics with the goal of creating a detector usable by all LHC experiment. Extensive progress on diamond quality, on the development of diamond trackers and on radiation hardness studies has been made. Transforming the technology to the LHC specific requirements is now underway. In this paper we present the recent progress achieved.

Nuclear techniques of analysis in diamond synthesis and annealing

Energy Technology Data Exchange (ETDEWEB)

Jamieson, D. N.; Prawer, S.; Gonon, P.; Walker, R.; Dooley, S.; Bettiol, A.; Pearce, J. [Melbourne Univ., Parkville, VIC (Australia). School of Physics

1996-12-31

Nuclear techniques of analysis have played an important role in the study of synthetic and laser annealed diamond. These measurements have mainly used ion beam analysis with a focused MeV ion beam in a nuclear microprobe system. A variety of techniques have been employed. One of the most important is nuclear elastic scattering, sometimes called non-Rutherford scattering, which has been used to accurately characterise diamond films for thickness and composition. This is possible by the use of a database of measured scattering cross sections. Recently, this work has been extended and nuclear elastic scattering cross sections for both natural boron isotopes have been measured. For radiation damaged diamond, a focused laser annealing scheme has been developed which produces near complete regrowth of MeV phosphorus implanted diamonds. In the laser annealed regions, proton induced x-ray emission has been used to show that 50 % of the P atoms occupy lattice sites. This opens the way to produce n-type diamond for microelectronic device applications. All these analytical applications utilize a focused MeV microbeam which is ideally suited for diamond analysis. This presentation reviews these applications, as well as the technology of nuclear techniques of analysis for diamond with a focused beam. 9 refs., 6 figs.

Diamond and silicon pixel detectors in high radiation environments

Energy Technology Data Exchange (ETDEWEB)

Tsung, Jieh-Wen

2012-10-15

Diamond pixel detector is a promising candidate for tracking of collider experiments because of the good radiation tolerance of diamond. The diamond pixel detector must withstand the radiation damage from 10{sup 16} particles per cm{sup 2}, which is the expected total fluence in High Luminosity Large Hadron Collider. The performance of diamond and silicon pixel detectors are evaluated in this research in terms of the signal-to-noise ratio (SNR). Single-crystal diamond pixel detectors with the most recent readout chip ATLAS FE-I4 are produced and characterized. Based on the results of the measurement, the SNR of diamond pixel detector is evaluated as a function of radiation fluence, and compared to that of planar-silicon ones. The deterioration of signal due to radiation damage is formulated using the mean free path of charge carriers in the sensor. The noise from the pixel readout circuit is simulated and calculated with leakage current and input capacitance to the amplifier as important parameters. The measured SNR shows good agreement with the calculated and simulated results, proving that the performance of diamond pixel detectors can exceed the silicon ones if the particle fluence is more than 10{sup 15} particles per cm{sup 2}.

Nuclear techniques of analysis in diamond synthesis and annealing

Energy Technology Data Exchange (ETDEWEB)

Jamieson, D N; Prawer, S; Gonon, P; Walker, R; Dooley, S; Bettiol, A; Pearce, J [Melbourne Univ., Parkville, VIC (Australia). School of Physics

1997-12-31

Nuclear techniques of analysis have played an important role in the study of synthetic and laser annealed diamond. These measurements have mainly used ion beam analysis with a focused MeV ion beam in a nuclear microprobe system. A variety of techniques have been employed. One of the most important is nuclear elastic scattering, sometimes called non-Rutherford scattering, which has been used to accurately characterise diamond films for thickness and composition. This is possible by the use of a database of measured scattering cross sections. Recently, this work has been extended and nuclear elastic scattering cross sections for both natural boron isotopes have been measured. For radiation damaged diamond, a focused laser annealing scheme has been developed which produces near complete regrowth of MeV phosphorus implanted diamonds. In the laser annealed regions, proton induced x-ray emission has been used to show that 50 % of the P atoms occupy lattice sites. This opens the way to produce n-type diamond for microelectronic device applications. All these analytical applications utilize a focused MeV microbeam which is ideally suited for diamond analysis. This presentation reviews these applications, as well as the technology of nuclear techniques of analysis for diamond with a focused beam. 9 refs., 6 figs.

Nuclear techniques of analysis in diamond synthesis and annealing

International Nuclear Information System (INIS)

Jamieson, D. N.; Prawer, S.; Gonon, P.; Walker, R.; Dooley, S.; Bettiol, A.; Pearce, J.

1996-01-01

Nuclear techniques of analysis have played an important role in the study of synthetic and laser annealed diamond. These measurements have mainly used ion beam analysis with a focused MeV ion beam in a nuclear microprobe system. A variety of techniques have been employed. One of the most important is nuclear elastic scattering, sometimes called non-Rutherford scattering, which has been used to accurately characterise diamond films for thickness and composition. This is possible by the use of a database of measured scattering cross sections. Recently, this work has been extended and nuclear elastic scattering cross sections for both natural boron isotopes have been measured. For radiation damaged diamond, a focused laser annealing scheme has been developed which produces near complete regrowth of MeV phosphorus implanted diamonds. In the laser annealed regions, proton induced x-ray emission has been used to show that 50 % of the P atoms occupy lattice sites. This opens the way to produce n-type diamond for microelectronic device applications. All these analytical applications utilize a focused MeV microbeam which is ideally suited for diamond analysis. This presentation reviews these applications, as well as the technology of nuclear techniques of analysis for diamond with a focused beam. 9 refs., 6 figs

Diamond and silicon pixel detectors in high radiation environments

International Nuclear Information System (INIS)

Tsung, Jieh-Wen

2012-10-01

Diamond pixel detector is a promising candidate for tracking of collider experiments because of the good radiation tolerance of diamond. The diamond pixel detector must withstand the radiation damage from 10 16 particles per cm 2 , which is the expected total fluence in High Luminosity Large Hadron Collider. The performance of diamond and silicon pixel detectors are evaluated in this research in terms of the signal-to-noise ratio (SNR). Single-crystal diamond pixel detectors with the most recent readout chip ATLAS FE-I4 are produced and characterized. Based on the results of the measurement, the SNR of diamond pixel detector is evaluated as a function of radiation fluence, and compared to that of planar-silicon ones. The deterioration of signal due to radiation damage is formulated using the mean free path of charge carriers in the sensor. The noise from the pixel readout circuit is simulated and calculated with leakage current and input capacitance to the amplifier as important parameters. The measured SNR shows good agreement with the calculated and simulated results, proving that the performance of diamond pixel detectors can exceed the silicon ones if the particle fluence is more than 10 15 particles per cm 2 .

New Myositis Classification Criteria-What We Have Learned Since Bohan and Peter.

Science.gov (United States)

Leclair, Valérie; Lundberg, Ingrid E

2018-03-17

Idiopathic inflammatory myopathy (IIM) classification criteria have been a subject of debate for many decades. Despite several limitations, the Bohan and Peter criteria are still widely used. The aim of this review is to discuss the evolution of IIM classification criteria. New IIM classification criteria are periodically proposed. The discovery of myositis-specific and myositis-associated autoantibodies led to the development of clinico-serological criteria, while in-depth description of IIM morphological features improved histopathology-based criteria. The long-awaited European League Against Rheumatism and American College of Rheumatology (EULAR/ACR) IIM classification criteria were recently published. The Bohan and Peter criteria are outdated and validated classification criteria are necessary to improve research in IIM. The new EULAR/ACR IIM classification criteria are thus a definite improvement and an important step forward in the field.

Functionalized diamond nanoparticles

KAUST Repository

Beaujuge, Pierre M.; El Tall, Omar; Raja, Inam U.

2014-01-01

A diamond nanoparticle can be functionalized with a substituted dienophile under ambient conditions, and in the absence of catalysts or additional reagents. The functionalization is thought to proceed through an addition reaction.

Functionalized diamond nanoparticles

KAUST Repository

Beaujuge, Pierre M.

2014-10-21

A diamond nanoparticle can be functionalized with a substituted dienophile under ambient conditions, and in the absence of catalysts or additional reagents. The functionalization is thought to proceed through an addition reaction.

CVD diamond pixel detectors for LHC experiments

CERN Document Server

Wedenig, R; Bauer, C; Berdermann, E; Bergonzo, P; Bogani, F; Borchi, E; Brambilla, A; Bruzzi, Mara; Colledani, C; Conway, J; Dabrowski, W; Delpierre, P A; Deneuville, A; Dulinski, W; van Eijk, B; Fallou, A; Fizzotti, F; Foulon, F; Friedl, M; Gan, K K; Gheeraert, E; Grigoriev, E; Hallewell, G D; Hall-Wilton, R; Han, S; Hartjes, F G; Hrubec, Josef; Husson, D; Kagan, H; Kania, D R; Kaplon, J; Karl, C; Kass, R; Knöpfle, K T; Krammer, Manfred; Lo Giudice, A; Lü, R; Manfredi, P F; Manfredotti, C; Marshall, R D; Meier, D; Mishina, M; Oh, A; Pan, L S; Palmieri, V G; Pernicka, Manfred; Peitz, A; Pirollo, S; Polesello, P; Pretzl, Klaus P; Procario, M; Re, V; Riester, J L; Roe, S; Roff, D G; Rudge, A; Runólfsson, O; Russ, J; Schnetzer, S R; Sciortino, S; Speziali, V; Stelzer, H; Stone, R; Suter, B; Tapper, R J; Tesarek, R J; Trawick, M L; Trischuk, W; Vittone, E; Wagner, A; Walsh, A M; Weilhammer, Peter; White, C; Zeuner, W; Ziock, H J; Zöller, M

1999-01-01

This paper reviews the development of CVD diamond pixel detectors. The preparation of the diamond pixel sensors for bump-bonding to the pixel readout electronics for the LHC and the results from beam tests carried out at CERN are described. (9 refs).

Benzene oxidation at diamond electrodes: comparison of microcrystalline and nanocrystalline diamonds.

Science.gov (United States)

Pleskov, Yu V; Krotova, M D; Elkin, V V; Varnin, V P; Teremetskaya, I G; Saveliev, A V; Ralchenko, V G

2012-08-27

A comparative study of benzene oxidation at boron-doped diamond (BDD) and nitrogenated nanocrystalline diamond (NCD) anodes in 0.5 M K(2)SO(4) aqueous solution is conducted by using cyclic voltammetry and electrochemical impedance spectroscopy. It is shown by measurements of differential capacitance and anodic current that during the benzene oxidation at the BDD electrode, adsorption of a reaction intermediate occurs, which partially blocks the electrode surface and lowers the anodic current. At the NCD electrode, benzene is oxidized concurrently with oxygen evolution, a (quinoid) intermediate being adsorbed at the electrode. The adsorption and the electrode surface blocking are reflected in the impedance-frequency and impedance-potential complex-plane plots. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

The Social Dynamics of the Peter Principle

Directory of Open Access Journals (Sweden)

P. Fiedor

2015-01-01

Full Text Available In this paper the author presents a critique of the recent computational studies looking at efficient promotion strategies in hierarchical organisations [1, 2], and presents his own study, more applicable for socio-economic systems. While previous research based on the Peter Principle [3] is an interesting and fresh (though grounds have been laid by [4] view on the problem of organisational efficiency, they do lack psychological and sociological basis so important in social sciences [5, 6]. Therefore the advice saying that it may be beneficial to promote worst employees or employees at random is not based on sound methodological grounds of social sciences [7]. In this paper two mechanisms are introduced to the model proposed by [1], which bring the computational study closer to real life organisations, rendering the analysis more enlightening for them and their strategies. The first introduces social dynamics allowing agents to conform to the perceived expectations of the organisation, and the latter frees the model from univariate analysis of the competence of an agent together with the crude mechanisms for its propagation between positions, exchanging it for multivariate analysis with mechanism based on the classic research by Henri Fayol [8]. The results of these simulations allow the author to conclude that despite the fact that Peter was right in principle; in real organisations the best way to promote employees is to choose the best employees, which is in agreement with the reality of most organisations [9]. The paper underlines the need to use the methodology of social science in econophysics.

Surface Texturing of CVD Diamond Assisted by Ultrashort Laser Pulses

Directory of Open Access Journals (Sweden)

Daniele M. Trucchi

2017-11-01

Full Text Available Diamond is a wide bandgap semiconductor with excellent physical properties which allow it to operate under extreme conditions. However, the technological use of diamond was mostly conceived for the fabrication of ultraviolet, ionizing radiation and nuclear detectors, of electron emitters, and of power electronic devices. The use of nanosecond pulse excimer lasers enabled the microstructuring of diamond surfaces, and refined techniques such as controlled ablation through graphitization and etching by two-photon surface excitation are being exploited for the nanostructuring of diamond. On the other hand, ultrashort pulse lasers paved the way for a more accurate diamond microstructuring, due to reduced thermal effects, as well as an effective surface nanostructuring, based on the formation of periodic structures at the nanoscale. It resulted in drastic modifications of the optical and electronic properties of diamond, of which “black diamond” films are an example for future high-temperature solar cells as well as for advanced optoelectronic platforms. Although experiments on diamond nanostructuring started almost 20 years ago, real applications are only today under implementation.

Electroluminescence Spectrum Shift with Switching Behaviour of Diamond Thin Films

Institute of Scientific and Technical Information of China (English)

王小平; 王丽军; 张启仁; 姚宁; 张兵临

2003-01-01

We report a special phenomenon on switching behaviour and the electroluminescence (EL) spectrum shift of doped diamond thin films. Nitrogen and cerium doped diamond thin films were deposited on a silicon substrate by microwave plasma-assisted chemical vapour deposition system and other special techniques. An EL device with a three-layer structure of nitrogen doped diamond/cerium doped diamond/SiO2 thin films was made. The EL device was driven by a direct-current power supply. Its EL character has been investigated, and a switching behaviour was observed. The EL light emission colour of diamond films changes from yellow (590nm) to blue (454 nm) while the switching behaviour appears.

Thermal diffusivity of diamond films using a laser pulse technique

International Nuclear Information System (INIS)

Albin, S.; Winfree, W.P.; Crews, B.S.

1990-01-01

Polycrystalline diamond films were deposited using a microwave plasma-enhanced chemical vapor deposition process. A laser pulse technique was developed to measure the thermal diffusivity of diamond films deposited on a silicon substrate. The effective thermal diffusivity of a diamond film on silicon was measured by observing the phase and amplitude of the cyclic thermal waves generated by laser pulses. An analytical model is presented to calculate the effective inplane (face-parallel) diffusivity of a two-layer system. The model is used to reduce the effective thermal diffusivity of the diamond/silicon sample to a value for the thermal diffusivity and conductivity of the diamond film

HFCVD Diamond-Coated Mechanical Seals

Directory of Open Access Journals (Sweden)

Raul Simões

2018-05-01

Full Text Available A mechanical seal promotes the connection between systems or mechanisms, preventing the escape of fluids to the exterior. Nonetheless, due to extreme working conditions, premature failure can occur. Diamond, due to its excellent properties, is heralded as an excellent choice to cover the surface of these devices and extend their lifetime. Therefore, the main objective of this work was to deposit diamond films over mechanical seals and test the coated seals on a water pump, under real working conditions. The coatings were created by hot filament chemical vapor deposition (HFCVD and two consecutive layers of micro- and nanocrystalline diamond were deposited. One of the main difficulties is the attainment of a good adhesion between the diamond films and the mechanical seal material (WC-Co. Nucleation, deposition conditions, and pre-treatments were studied to enhance the coating. Superficial wear or delamination of the film was investigated using SEM and Raman characterization techniques, in order to draw conclusions about the feasibility of these coatings in the WC-Co mechanical seals with the purpose of increasing their performance and life time. The results obtained gave a good indication about the feasibility of this process and the deposition conditions used, with the mechanical seals showing no wear and no film delamination after a real work environment test.

Leading South African lawyer tours Tallinn = Lõuna-Aafrika tippadvokaat Tallinnas / Peter Whelan

Index Scriptorium Estoniae

Whelan, Peter

2007-01-01

Eesti advokaadibüroo Lepik & Luhaäär LAWIN kutsel külastas septembris 2007 Tallinna maailma tuntuima sõltumatute advokaadibüroode assotsiatsiooni Lex Mundi Lõuna-Aafrikast pärit juhatuse liige Peter Whelan

Tilda Swintoni uskumatu elu / Tilda Swinton ; intervjueerinud Peter Cowie, refereerinud Margit Tõnson

Index Scriptorium Estoniae

Swinton, Tilda, 1960-

2009-01-01

Berliini 59. rahvusvahelise filmifestivali poolt ellu kutsutud ja noortele talentidele mõeldud "Berlinale Talent Campus" vestluste sari nimega "Rambivalgus". Vestlust Berlinale võistlusprogrammi žürii esinaise Tilda Swintoniga modereeris filmiajaloolane Peter Cowie, vahendas Margit Tõnson

Diamond-like carbon coated ultracold neutron guides

International Nuclear Information System (INIS)

Heule, S.; Atchison, F.; Daum, M.; Foelske, A.; Henneck, R.; Kasprzak, M.; Kirch, K.; Knecht, A.; Kuzniak, M.; Lippert, T.; Meier, M.; Pichlmaier, A.; Straumann, U.

2007-01-01

It has been shown recently that diamond-like carbon (DLC) with a sp 3 fraction above 60% is a better wall coating material for ultracold neutron applications than beryllium. We report on results of Raman spectroscopic and XPS measurements obtained for diamond-like carbon coated neutron guides produced in a new facility, which is based on pulsed laser deposition at 193 nm. For diamond-like carbon coatings on small stainless steel substrates we find sp 3 fractions in the range from 60 to 70% and showing slightly increasing values with laser pulse energy and pulse repetition rate

Indigenous development of diamond detectors for monitoring neutrons

International Nuclear Information System (INIS)

Singh, Arvind; Amit Kumar; Topkar, Anita; Pithawa, C.K.

2013-01-01

High purity synthetic chemically vapor deposited (CVD) diamond has several outstanding characteristics that make it as an important material for detector applications specifically for extreme environmental conditions like high temperature, high radiation, and highly corrosive environments. Diamond detectors are especially considered promising for monitoring fast neutrons produced by the D-T nuclear fusion reactions in next generation fusion facilities such as ITER. When fast neutrons interact with carbon, elastic, inelastic and (n,α) type reactions can occur. These reactions can be employed for the detection of fast neutrons using diamond. We have initiated the development of diamond detectors based on synthetic CVD substrates. In this paper, the first test of a polycrystalline CVD diamond detector with fast neutrons is reported. The test results demonstrate that this detector can be used for monitoring fast neutrons. The diamond detectors have been fabricated using 5 mm x 5 mm, 300 μm polycrystalline diamond substrates. Aluminum metallization has been used on both sides of the detector to provide electrical contacts. The performance of fabricated detectors was first evaluated using current and capacitance measurements. The leakage current was observed to be stable and about a few pAs for voltages up to 300V. The capacitance-voltage characteristics showed a constant capacitance which is as expected. To confirm the response of the detector to charged particles, the pulse height spectrum (PHS) was obtained using 238 Pu- 239 Pu dual α- source. The PHS showed a continuum without any peak due to polycrystalline nature of diamond film. The response of the detector to fast neutrons has been studied using the fast neutron facility at NXF, BARC. The PHS obtained for a neutron yield of 4 x 10 8 n/s is shown. The average counts per second (cps) measured for diamond detector for different neutron yields is shown. The plot shows linearity with coefficient of determination R

Diamond window and its application to ITER gyrotron

International Nuclear Information System (INIS)

Sakamoto, K.

1999-01-01

On the background of having to reduce the overall cost for ITER to 50% it is proposed to replace conventional glass windows on gyrotrons by diamonds. The successful production and testing of such diamond windows is reported. A diamond window can transmit 5 times more power than usual double disk transmission windows while only costing 3 times as much. As a tradeoff, the gyrotrons could be replaced by more powerful ones and one would need fewer of them

Method to fabricate micro and nano diamond devices

Energy Technology Data Exchange (ETDEWEB)

Morales, Alfredo M.; Anderson, Richard J.; Yang, Nancy Y. C.; Skinner, Jack L.; Rye, Michael J.

2017-04-11

A method including forming a diamond material on the surface of a substrate; forming a first contact and a separate second contact; and patterning the diamond material to form a nanowire between the first contact and the second contact. An apparatus including a first contact and a separate second contact on a substrate; and a nanowire including a single crystalline or polycrystalline diamond material on the substrate and connected to each of the first contact and the second contact.

Peter Carey's Laptop

Directory of Open Access Journals (Sweden)

Rowan Wilken

2014-03-01

Full Text Available In 2001, the State Library of Victoria in Melbourne built on its holdings of Australian literary manuscripts by acquiring all the papers, drafts and other items associated with Peter Carey’s Booker Prize-winning novel, True History of the Kelly Gang. The centrepiece of this acquisition, and the focus of this article, is Carey’s Apple Mac Classic laptop computer. The argument that is developed in this article is that Carey’s laptop is a technological artefact that operates, especially at the time of its acquisition, as an important talisman in three interrelated senses. First, it was viewed by library staff as a key means of gaining access to the ‘true history’ of Carey’s own creative drive or creative unconscious. Second, its public display alongside other textual objects (mostly books served to reinforce a reconstructed corporate image that endeavoured to reposition the library as a vital contemporary cultural site and key player in Melbourne’s institutional gallery scene. Third, it was a crucial symbolic acquisition insofar as it spoke to certain desires within library management at that time, and which responded to similar moves at major libraries elsewhere around the world, to embrace collection digitisation as the path forward.

Socio-historical impulse in literature: a study of Peter Abrahams ...

African Journals Online (AJOL)

Peter Abrahams is one of those who believe that with fiction, certain abnormalities in a society can be remedied thus Mine Boy albeitseen by some as a journalistic history of the South African society, like other works of art, is pure fiction, whose inspiration comes by what happens around the author. Our interest in this paper ...

Chemical vapour deposition synthetic diamond: materials, technology and applications

International Nuclear Information System (INIS)

Balmer, R S; Brandon, J R; Clewes, S L; Dhillon, H K; Dodson, J M; Friel, I; Inglis, P N; Madgwick, T D; Markham, M L; Mollart, T P; Perkins, N; Scarsbrook, G A; Twitchen, D J; Whitehead, A J; Wilman, J J; Woollard, S M

2009-01-01

Substantial developments have been achieved in the synthesis of chemical vapour deposition (CVD) diamond in recent years, providing engineers and designers with access to a large range of new diamond materials. CVD diamond has a number of outstanding material properties that can enable exceptional performance in applications as diverse as medical diagnostics, water treatment, radiation detection, high power electronics, consumer audio, magnetometry and novel lasers. Often the material is synthesized in planar form; however, non-planar geometries are also possible and enable a number of key applications. This paper reviews the material properties and characteristics of single crystal and polycrystalline CVD diamond, and how these can be utilized, focusing particularly on optics, electronics and electrochemistry. It also summarizes how CVD diamond can be tailored for specific applications, on the basis of the ability to synthesize a consistent and engineered high performance product.

Regrowth zones in laser annealed radiation damaged diamond

International Nuclear Information System (INIS)

Jamieson, D.N.; Prawer, S.; Dooley, S.P.; Kalish, R.; Technion-Israel Inst. of Tech., Haifa

1993-01-01

Focused laser annealing of ion implanted diamond with a 15 μm diameter laser spot produces as variety of effects that depend on the power density of the laser. Channeling Contrast Microscopy (CCM) provides a relatively straight forward, rapid, method to analyse the annealed regions of the diamond to characterize the effects. In order of increasing laser power density, effects that are observed include: regrowth of the end of range damage of the ion implantation, formation of a buried graphitic layer and complete graphitization of the surface of the diamond down to the bottom of the original damage layer. Information provided by CCM leads to an understanding the causes of these effects and provides insight into the carbon phase diagram in the neighbourhood of the graphite to diamond phase transition. Analysis of the effects of laser annealing by CCM are complicated by the swelling of the diamond lattice caused by the original ion implantation, compaction following regrowth and the effect of the analysis beam irradiation itself. 12 refs., 5 figs

Fabrication of planarised conductively patterned diamond for bio-applications

Energy Technology Data Exchange (ETDEWEB)

Tong, Wei [School of Physics, University of Melbourne, Parkville, Victoria (Australia); Fox, Kate, E-mail: kfox@unimelb.edu.au [School of Physics, University of Melbourne, Parkville, Victoria (Australia); Ganesan, Kumaravelu [School of Physics, University of Melbourne, Parkville, Victoria (Australia); Turnley, Ann M. [Department of Anatomy and Neuroscience, University of Melbourne, Parkville, Victoria (Australia); Shimoni, Olga [School of Physics, University of Melbourne, Parkville, Victoria (Australia); Tran, Phong A. [Department of Chemical and Biomolecular Engineering, University of Melbourne, Parkville, Victoria (Australia); Lohrmann, Alexander; McFarlane, Thomas; Ahnood, Arman; Garrett, David J. [School of Physics, University of Melbourne, Parkville, Victoria (Australia); Meffin, Hamish [National Information and Communication Technology Australia, Victoria 3010 (Australia); Department of Electrical and Electronic Engineering, University of Melbourne, Victoria 3010 (Australia); O' Brien-Simpson, Neil M.; Reynolds, Eric C. [Oral Health Cooperative Research Centre, Melbourne Dental School, The University of Melbourne, 720 Swanston Street, Victoria 3010 (Australia); Prawer, Steven [School of Physics, University of Melbourne, Parkville, Victoria (Australia)

2014-10-01

The development of smooth, featureless surfaces for biomedical microelectronics is a challenging feat. Other than the traditional electronic materials like silicon, few microelectronic circuits can be produced with conductive features without compromising the surface topography and/or biocompatibility. Diamond is fast becoming a highly sought after biomaterial for electrical stimulation, however, its inherent surface roughness introduced by the growth process limits its applications in electronic circuitry. In this study, we introduce a fabrication method for developing conductive features in an insulating diamond substrate whilst maintaining a planar topography. Using a combination of microwave plasma enhanced chemical vapour deposition, inductively coupled plasma reactive ion etching, secondary diamond growth and silicon wet-etching, we have produced a patterned substrate in which the surface roughness at the interface between the conducting and insulating diamond is approximately 3 nm. We also show that the patterned smooth topography is capable of neuronal cell adhesion and growth whilst restricting bacterial adhesion. - Highlights: • We have fabricated a planar diamond device with conducting and insulating features. • A precise method is provided using CVD and RIE techniques to develop the substrate. • The step between conducting and insulating features is less than 3 nm. • Planar topography promotes neuronal cell adhesion and restricts bacterial adhesion. • Neuronal cells prefer conductive diamond (N-UNCD) to non-conductive diamond (UNCD)

Performance Evaluation Tests for Environmental Research (PETER): evaluation of 114 measures

Science.gov (United States)

Bittner, A. C. Jr; Carter, R. C.; Kennedy, R. S.; Harbeson, M. M.; Krause, M.

1986-01-01

The goal of the Performance Evaluation Tests for Environmental Research (PETER) Program was to identify a set of measures of human capabilities for use in the study of environmental and other time-course effects. 114 measures studied in the PETER Program were evaluated and categorized into four groups based upon task stability and task definition. The Recommended category contained 30 measures that clearly obtained total stabilization and had an acceptable level of reliability efficiency. The Acceptable-But-Redundant category contained 15 measures. The 37 measures in the Marginal category, which included an inordinate number of slope and other derived measures, usually had desirable features which were outweighed by faults. The 32 measures in the Unacceptable category had either differential instability or weak reliability efficiency. It is our opinion that the 30 measures in the Recommended category should be given first consideration for environmental research applications. Further, it is recommended that information pertaining to preexperimental practice requirements and stabilized reliabilities should be utilized in repeated-measures environmental studies.

Phenomenological effets of tantalum incorporation into diamond films: Experimental and first principle studies

Energy Technology Data Exchange (ETDEWEB)

Ullah, Mahtab, E-mail: mahtabullah@bzu.edu.pk [Department of Physics, Bahauddin Zakariya University Multan (Pakistan); Rana, Anwar Manzoor; Ahmad, E. [Department of Physics, Bahauddin Zakariya University Multan (Pakistan); Raza, Rizwan [Department of Physics, COMSATS Institute of Information Technology, Lahore-54000 (Pakistan); Hussain, Fayyaz [Department of Physics, Bahauddin Zakariya University Multan (Pakistan); Hussain, Akhtar; Iqbal, Muhammad [Theoretical Physics Division, PINSTECH, P.O. Nilore, Islamabad (Pakistan)

2016-09-01

Graphical abstract: - Highlights: • Fabrication of tantalum incorporated diamonds films using HFCVD technique. • Decrease in resistivity by increasing tantalum content in diamond thin films. • Electronic structure calculations of tantalum incorporated diamonds films through VASP code. • A rise of bond length and bond angles by addition of tantalum in the diamond lattice. • Confirmation of decrease of resistivity by adding tantalum due to creation of impurity states in the bandgap. - Abstract: Tantalum (Ta) incorporated diamond films are synthesized on silicon substrate by chemical vapor deposition under gas mixture of CH{sub 4} + H{sub 2}. Characterizations of the resulting films indicate that morphology and resistivity of as-grown diamond films are significantly influenced by the process parameters and the amount of tantalum incorporated in the diamond films. XRD plots reveal that diamond films are composed of TaC along with diamond for higher concentration of tantalum and Ta{sub 2}C phases for lower concentration of tantalum. EDS spectra confirms the existence of tantalum in the diamond films. Resistivity measurements illustrate a sudden fall of about two orders of magnitude by the addition of tantalum in the diamond films. Band structure of Ta-incorporated diamond has been investigated based on density functional theory (DFT) using VASP code. Band structure calculations lead to the semiconducting behavior of Ta-incorporated diamond films because of the creation of defects states inside the band gap extending towards conduction band minimum. Present DFT results support experimental trend of resistivity that with the incorporation of tantalum into diamond lattice causes a decrease in the resistivity of diamond films so that tantalum-incorporated diamond films behave like a good semiconductor.

The Mysteries of Diamonds: Bizarre History, Amazing Properties, Unique Applications

International Nuclear Information System (INIS)

Kagan, Harris

2008-01-01

Diamonds have been a prized material throughout history. They are scarce and beautiful, wars have been fought over them, and they remain today a symbol of wealth and power. Diamonds also have exceptional physical properties which can lead to unique applications in science. There are now techniques to artificially synthesize diamonds of extraordinarily high quality. In this talk, Professor Kagan will discuss the history of diamonds, their bizarre properties, and their manufacture and use for 21st century science.

The Mysteries of Diamonds: Bizarre History, Amazing Properties, Unique Applications

Energy Technology Data Exchange (ETDEWEB)

Kagan, Harris (Ohio State University)

2008-06-24

Diamonds have been a prized material throughout history. They are scarce and beautiful, wars have been fought over them, and they remain today a symbol of wealth and power. Diamonds also have exceptional physical properties which can lead to unique applications in science. There are now techniques to artificially synthesize diamonds of extraordinarily high quality. In this talk, Professor Kagan will discuss the history of diamonds, their bizarre properties, and their manufacture and use for 21st century science.

Diamonds at the golden point

CERN Multimedia

Katarina Anthony

2015-01-01

Alongside the CMS Pixel Luminosity Telescope (PLT) – installed last month (see here) – lie diamond detectors. No ordinary gems, these lab-grown diamonds will be playing a vital role in Run 2: differentiating signals from collision products with those from the beam background.   The BCM detector's green "c-shaped" printed circuit board is mounted on the PLT/BCM carbon-fibre carriage ready for installation. Earlier this year, the CMS BRIL project installed beam condition monitors (BCM) at the heart of the CMS detector. Designed to measure the online luminosity and beam background as close as possible to the LHC beam pipe, the BCMs use radiation-hard diamonds to differentiate between background and collision signals. The BCM also protects the CMS silicon trackers from damaging beam losses, by aborting the beam if the signal currents measured are above an acceptable threshold. These new BCMs are designed with Run 2 bunches in mind. &ldq...

ATLAS diamond Beam Condition Monitor

CERN Document Server

Gorišek, A; Dolenc, I; Frais-Kölbl, H; Griesmayer, E; Kagan, H; Korpar, S; Kramberger, G; Mandic, I; Meyer, M; Mikuz, M; Pernegger, H; Smith, S; Trischuk, W; Weilhammer, P; Zavrtanik, M

2007-01-01

The ATLAS experiment has chosen to use diamond for its Beam Condition Monitor (BCM) given its radiation hardness, low capacitance and short charge collection time. In addition, due to low leakage current diamonds do not require cooling. The ATLAS Beam Condition Monitoring system is based on single beam bunch crossing measurements rather than integrating the accumulated particle flux. Its fast electronics will allow separation of LHC collisions from background events such as beam gas interactions or beam accidents. There will be two stations placed symmetrically about the interaction point along the beam axis at . Timing of signals from the two stations will provide almost ideal separation of beam–beam interactions and background events. The ATLAS BCM module consists of diamond pad detectors of area and thickness coupled to a two-stage RF current amplifier. The production of the final detector modules is almost done. A S/N ratio of 10:1 has been achieved with minimum ionizing particles (MIPs) in the test bea...

Status of diamond particle detectors

Science.gov (United States)

Krammer, M.; Adam, W.; Bauer, C.; Berdermann, E.; Bogani, F.; Borchi, E.; Bruzzi, M.; Colledani, C.; Conway, J.; Dabrowski, W.; Delpierre, P.; Deneuville, A.; Dulinski, W.; van Eijk, B.; Fallou, A.; Fish, D.; Foulon, F.; Friedl, M.; Gan, K. K.; Gheeraert, E.; Grigoriev, E.; Hallewell, G.; Hall-Wilton, R.; Han, S.; Hartjes, F.; Hrubec, J.; Husson, D.; Kagan, H.; Kania, D.; Kaplon, J.; Kass, R.; Knöpfle, K. T.; Manfredi, P. F.; Meier, D.; Mishina, M.; LeNormand, F.; Pan, L. S.; Pernegger, H.; Pernicka, M.; Re, V.; Riester, G. L.; Roe, S.; Roff, D.; Rudge, A.; Schnetzer, S.; Sciortino, S.; Speziali, V.; Stelzer, H.; Stone, R.; Tapper, R. J.; Tesarek, R.; Thomson, G. B.; Trawick, M.; Trischuk, W.; Turchetta, R.; Walsh, A. M.; Wedenig, R.; Weilhammer, P.; Ziock, H.; Zoeller, M.

1998-11-01

To continue the exciting research in the field of particle physics new accelerators and experiments are under construction. In some of these experiments, e.g. ATLAS and CMS at the Large Hadron Collider at CERN or HERA-B at DESY, the detectors have to withstand an extreme environment. The detectors must be radiation hard, provide a very fast signal, and be as thin as possible. The properties of CVD diamond allow to fulfill these requirements and make it an ideal material for the detectors close to the interaction region of these experiments, i.e. the vertex detectors or the inner trackers. The RD42 collaboration is developing diamond detectors for these applications. The program of RD42 includes the improvement of the charge collection properties of CVD diamond, the study of the radiation hardness and the development of low-noise radiation hard readout electronics. An overview of the progress achieved during the last years will be given.

Origin, state of the art and some prospects of the diamond CVD

CERN Document Server

Spitsyn, B V; Alexenko, A E

2000-01-01

A short review on the diamond CVD origin, together with its state of the art and some prospects was given. New hybrid methods of the diamond CVD permit to gain 1.2 to 6 times of growth rate in comparison with ordinary diamond CVD's. Recent results on n-type diamond film synthesis through phosphorus doping in the course of the CVD process are briefly discussed. In comparison with high-pressure diamond synthesis, the CVD processes open new facets of the diamond as ultimate crystal for science and technology evolution. It was stressed that, mainly on the basis of new CVDs of diamond, the properties of natural diamond are not only reproduced, but can be surpassed. As examples, mechanical (fracture resistance), physical (thermal conductivity), and chemical (oxidation stability) properties are mentioned. Some present issues in the field are considered.

Initial damage processes for diamond film exposure to hydrogen plasma

International Nuclear Information System (INIS)

Deslandes, A.; Guenette, M.C.; Samuell, C.M.; Karatchevtseva, I.; Ionescu, M.; Cohen, D.D.; Blackwell, B.; Corr, C.; Riley, D.P.

2013-01-01

Graphical abstract: -- Highlights: • Exposing chemical vapour deposited (CVD) diamond films in a recently constructed device, MAGPIE, specially commissioned to simulate fusion plasma conditions. • Non-diamond material is etched from the diamond. • There is no hydrogen retention observed, which suggests diamond is an excellent candidate for plasma facing materials. • Final structure of the surface is dependent on synergistic effects of etching and ion-induced structural change. -- Abstract: Diamond is considered to be a possible alternative to other carbon based materials as a plasma facing material in nuclear fusion devices due to its high thermal conductivity and resistance to chemical erosion. In this work CVD diamond films were exposed to hydrogen plasma in the MAGnetized Plasma Interaction Experiment (MAGPIE): a linear plasma device at the Australian National University which simulates plasma conditions relevant to nuclear fusion. Various negative sample stage biases of magnitude less than 500 V were applied to control the energies of impinging ions. Characterisation results from SEM, Raman spectroscopy and ERDA are presented. No measureable quantity of hydrogen retention was observed, this is either due to no incorporation of hydrogen into the diamond structure or due to initial incorporation as a hydrocarbon followed by subsequent etching back into the plasma. A model is presented for the initial stages of diamond erosion in fusion relevant hydrogen plasma that involves chemical erosion of non-diamond material from the surface by hydrogen radicals and damage to the subsurface region from energetic hydrogen ions. These results show that the initial damage processes in this plasma regime are comparable to previous studies of the fundamental processes as reported for less extreme plasma such as in the development of diamond films

Nucleation of microwave plasma CVD diamond on molybdenum (Mo) substrate

International Nuclear Information System (INIS)

Inderjeet, K.; Ramesh, S.

2000-01-01

Molybdenum is a metal, which is gaining increasing significance in industrial applications. The main use of Mo is as all alloying element added in small amounts to steel, irons and non- ferrous alloys in order to enhance the strength, toughness and wear resistance. Mo is also vastly being employed in the automotive and aircraft industries, mainly due to its low coefficient of friction. Diamond, on be other hand, is a unique material for innumerable applications because of its usual combination of physical and chemical properties. Several potential applications can be anticipated for diamond in many sectors including electronics, optics, as protective corrosion resistant coatings, cutting tools, etc. With the enhancement in science and technology, diamond microcrystals and thin films are now being produced from the vapour phase by a variety of chemical vapour deposition (CVD) techniques; such as microwave plasma CVD. With such technology being made available, it is envisage that diamond-coated molybdenum would further enhance the performance and to open up new avenue for Mo in various industries. Therefore, it is the aim of the present work to study the nucleation and growth of diamond particles on Mo surface by employing microwave plasma CVD (MAPCVD). In the present work, diamond deposition was carried out in several stages by varying the deposition distance. The nucleation and growth rate were studied using scanning electron microscopy (SEM). In addition, the existence of diamond was verified by X-ray diffraction (XRD) analysis. It has been found that the nucleation and growth rate of diamond particles were influenced by the deposition height between the substrate and plasma. Under the optimum condition, well defined diamond crystallites distributed homogeneously throughout the surface, could be obtained. Some of the important parameters controlling the deposition and growth of diamond particles on Mo surface are discussed. (author)

Advances in diamond tools for working lithoid materials

International Nuclear Information System (INIS)

Rosso, M.; Ugues, D.; Valle, A.

2001-01-01

Lithoid material is a general definition to indicate a wide category of ornamental materials: they can be divided into natural (i.e. granite) or artificial (i.e. conglomerates and ceramics). All the lithoid materials are subjected to surface machining operations in order to obtain final work piece ready to be introduced an the market in form of slabs or tiles. This paper deals with the attempts of producing a machining diamond tools using a sintered steel binder. The opportunity of using a steel binder has been already highly studied by diamond tools industry, but with not satisfying outcomes and not longer developed, basically due to the catalysis action of iron and to the diamond degradation mechanism provided by high processing temperature. The binding matrix was produced by infiltration sintering. Infiltration requires the pore structure to be open and interconnected; thus, the sintered solid skeleton must have an at least 10 % porosity. Therefore, the infiltration sintering of the steel skeleton uses a temperature lower than the usually required for steel sintering one. Using the suitable infiltration agent will result in low infiltration temperature levels too (1). This should give the opportunity to work with a steel binder for diamond dispersed machining tools, without causing excessive damages to the diamond mechanical properties. The paper aims at overcoming the diamond degradation by lowering the production temperature using a definitively controlled infiltration sintering process. (author)

Study of Electron Transport and Amplification in Diamond

Energy Technology Data Exchange (ETDEWEB)

Ben-Zvi, Ilan [Stony Brook Univ., NY (United States); Muller, Erik [Stony Brook Univ., NY (United States)

2015-01-05

The development of the Diamond Amplified Photocathode (DAP) has produced significant results under our previous HEP funded efforts both on the fabrication of working devices and the understanding of the underlying physics governing its performance. The results presented here substantiate the use of diamond as both a secondary electron amplifier for high-brightness, high-average-current electron sources and as a photon and particle detector in harsh radiation environments. Very high average current densities (>10A/cm2) have been transported through diamond material. The transport has been measured as a function of incident photon energy and found to be in good agreement with theoretical models. Measurements of the charge transport for photon energies near the carbon K-edge (290 eV for sp3 bonded carbon) have provided insight into carrier loss due to diffusion; modeling of this aspect of charge transport is underway. The response of diamond to nanosecond x-ray pulses has been measured; in this regime the charge transport is as expected. Electron emission from hydrogenated diamond has been measured using both electron and x-ray generated carriers; a gain of 178 has been observed for electron-generated carriers. The energy spectrum of the emitted electrons has been measured, providing insight into the electron affinity and ultimately the thermal emittance. The origin of charge trapping in diamond has been investigated for both bulk and surface trapping

Elastic constants of diamond from molecular dynamics simulations

International Nuclear Information System (INIS)

Gao Guangtu; Van Workum, Kevin; Schall, J David; Harrison, Judith A

2006-01-01

The elastic constants of diamond between 100 and 1100 K have been calculated for the first time using molecular dynamics and the second-generation, reactive empirical bond-order potential (REBO). This version of the REBO potential was used because it was redesigned to be able to model the elastic properties of diamond and graphite at 0 K while maintaining its original capabilities. The independent elastic constants of diamond, C 11 , C 12 , and C 44 , and the bulk modulus were all calculated as a function of temperature, and the results from the three different methods are in excellent agreement. By extrapolating the elastic constant data to 0 K, it is clear that the values obtained here agree with the previously calculated 0 K elastic constants. Because the second-generation REBO potential was fit to obtain better solid-state force constants for diamond and graphite, the agreement with the 0 K elastic constants is not surprising. In addition, the functional form of the second-generation REBO potential is able to qualitatively model the functional dependence of the elastic constants and bulk modulus of diamond at non-zero temperatures. In contrast, reactive potentials based on other functional forms do not reproduce the correct temperature dependence of the elastic constants. The second-generation REBO potential also correctly predicts that diamond has a negative Cauchy pressure in the temperature range examined

OSL and TL dosimeter characterization of boron doped CVD diamond films

Science.gov (United States)

Gonçalves, J. A. N.; Sandonato, G. M.; Meléndrez, R.; Chernov, V.; Pedroza-Montero, M.; De la Rosa, E.; Rodríguez, R. A.; Salas, P.; Barboza-Flores, M.

2005-04-01

Natural diamond is an exceptional prospect for clinical radiation dosimetry due to its tissue-equivalence properties and being chemically inert. The use of diamond in radiation dosimetry has been halted by the high market price; although recently the capability of growing high quality CVD diamond has renewed the interest in using diamond films as radiation dosimeters. In the present work we have characterized the dosimetric properties of diamond films synthesized by the HFCVD method. The thermoluminescence and the optically stimulated luminescence of beta exposed diamond sample containing a B/C 4000 ppm doping presents excellent properties suitable for dosimetric applications with β-ray doses up to 3.0 kGy. The observed OSL and TL performance is reasonable appropriate to justify further investigation of diamond films as dosimeters for ionizing radiation, specially in the radiotherapy field where very well localized and in vivo and real time radiation dose applications are essential.

Improvements in or relating to artefacts incorporating industrial diamonds

International Nuclear Information System (INIS)

Hartley, N.E.W.; Poole, M.J.

1981-01-01

A process for improving the wear characteristics of industrial diamonds is described which consists of implanting into the surface regions of the diamonds, ions of a material having an atomic weight greater than one and such as to affect the surface properties of the diamonds. Examples of the invention, in which N + and C + ions have been used, are cited. (U.K.)

Critical components for diamond-based quantum coherent devices

International Nuclear Information System (INIS)

Greentree, Andrew D; Olivero, Paolo; Draganski, Martin; Trajkov, Elizabeth; Rabeau, James R; Reichart, Patrick; Gibson, Brant C; Rubanov, Sergey; Huntington, Shane T; Jamieson, David N; Prawer, Steven

2006-01-01

The necessary elements for practical devices exploiting quantum coherence in diamond materials are summarized, and progress towards their realization documented. A brief review of future prospects for diamond-based devices is also provided

Diamond Jubilee Meeting

Indian Academy of Sciences (India)

1994-10-01

Oct 1, 1994 ... Science, Bangalore, the Diamond Jubilee Annual. Meeting will be held in ... "The fascination of statistics" .... on post Hartree-Fock methods, highly correlated systems ..... Gold Medal of the National Institute of Social. Sciences ...

Studies on synthesis of diamond at high pressure and temperature

Science.gov (United States)

Kailath, Ansu J.

Diamond is an essential material of modern industry and probably the most versatile abrasive available today. It also has many other industrial applications attributable to its unique mechanical, optical, thermal and electrical properties. Its usage has grown to the extent that there is hardly a production process in modern industry in which industrial diamond does not play a part. Bulk diamond production today is a major industry. Diamonds can be produced in its thermodynamically stable regions either by direct static conversion, or shock-wave conversion. The pressures and temperatures required for direct static conversion are very high. In the catalyst-solvent method, the material used establishes a reaction path with lower activation energy than for direct transformation. This helps in a quicker transformation under more benign conditions. Hence, catalyst-solvent synthesis is readily accomplished and is now a viable and successful industrial process. Diamonds produced by shock wave are very small (approximately 60mu). Therefore this diamond is limited to applications such as polishing compounds only. The quality, quantity, size and morphology of the crystals synthesized by catalyst-solvent process depend on different conditions employed for synthesis. These details, because of commercial reasons are not disclosed in published literature. Hence, systematic studies have been planned to investigate the effect of various growth parameters on the synthesized crystals. During the growth of synthetic diamond crystals, some catalyst-solvent is retained into the crystals in some form and behaves like an impurity. Several physico-mechanical properties of the crystals are found to depend on the total quantity and distribution of these inclusions. Thus, detailed investigation of the crystallization medium and inclusions in synthesized diamonds was also undertaken in the present work. The work incorporated in this thesis has been divided into seven chapters. The first

Chemical vapor deposition of nanocrystalline diamond films

International Nuclear Information System (INIS)

Vyrovets, I.I.; Gritsyna, V.I.; Dudnik, S.F.; Opalev, O.A.; Reshetnyak, O.M.; Strel'nitskij, V.E.

2008-01-01

The brief review of the literature is devoted to synthesis of nanocrystalline diamond films. It is shown that the CVD method is an effective way for deposition of such nanostructures. The basic technological methods that allow limit the size of growing diamond crystallites in the film are studied.

X-ray absorption and emission studies of diamond nanoparticles

International Nuclear Information System (INIS)

Van Buuren, T.; Willey, T.; Raty, J.Y.; Galli, G.; Terminello, L.J.; Bostedt, C.

2004-01-01

Full text: A new family of carbon nanopaticles produced in detonations, are found to have a core of diamond with a coating fullerene- like carbon. X-ray diffraction and TEM show that the nanodiamond powder is crystalline and approximately 4 nm in diameter. These nano-sized diamonds do not display the characteristic property of other group IV nanoparticles: a strong widening of the energy gap between the conduction and valence bands owing to quantum-confinement effects. For nano-sized diamond with a size distribution of 4 nm, there is no shift of the band energies relative to bulk diamond. Although the C1s core exciton feature clearly observed in the K-edge absorption edge of bulk diamond is shifted and broadening due to increased overlap of the excited electron with the core holein the small particle. Also the depth of the second gap in the nanodiamond spectra is shallower than that of bulk diamond. A feature at lower energy in the X-ray absorption spectra that is not present in the bulk samples is consistent with a fullerene like surface reconstruction. By exposing the diamond nanoparticles to an Argon /Oxygen plasma then annealing in a UHV environment we have obtained a hydrogen free surface. The nanodiamonds processed in this manner show an increase fullerene type contribution in the carbon x-ray absorption pre-edge. High spatial resolution EELS measurements of the empty states of a single nanodiamond particle acquired with a ld emission TEM also show the core of the particle is bulk diamond like where as the surface has a fullerene like structure. Standard density-functional calculations on clusters in which the diamond surface bonds are terminated with hydrogen atoms, show that the bandgap begins to increase above the bulk value only for clusters smaller than 1 nm. Surface hydrogen atoms are found to be about as close as they do in molecular hydrogen and can escape as H 2 , forcing the respective carbon atoms to rearrange. A series of such rearrangements can

Electron field emission for ultrananocrystalline diamond films

Energy Technology Data Exchange (ETDEWEB)

Krauss, A. R.; Auciello, O.; Ding, M. Q.; Gruen, D. M.; Huang, Y.; Zhirnov, V. V.; Givargizov, E. I.; Breskin, A.; Chechen, R.; Shefer, E. (and others)

2001-03-01

Ultrananocrystalline diamond (UNCD) films 0.1--2.4 {mu}m thick were conformally deposited on sharp single Si microtip emitters, using microwave CH{sub 4}--Ar plasma-enhanced chemical vapor deposition in combination with a dielectrophoretic seeding process. Field-emission studies exhibited stable, extremely high (60--100 {mu}A/tip) emission current, with little variation in threshold fields as a function of film thickness or Si tip radius. The electron emission properties of high aspect ratio Si microtips, coated with diamond using the hot filament chemical vapor deposition (HFCVD) process were found to be very different from those of the UNCD-coated tips. For the HFCVD process, there is a strong dependence of the emission threshold on both the diamond coating thickness and Si tip radius. Quantum photoyield measurements of the UNCD films revealed that these films have an enhanced density of states within the bulk diamond band gap that is correlated with a reduction in the threshold field for electron emission. In addition, scanning tunneling microscopy studies indicate that the emission sites from UNCD films are related to minima or inflection points in the surface topography, and not to surface asperities. These data, in conjunction with tight binding pseudopotential calculations, indicate that grain boundaries play a critical role in the electron emission properties of UNCD films, such that these boundaries: (a) provide a conducting path from the substrate to the diamond--vacuum interface, (b) produce a geometric enhancement in the local electric field via internal structures, rather than surface topography, and (c) produce an enhancement in the local density of states within the bulk diamond band gap.

Natural occurrence of pure nano-polycrystalline diamond from impact crater

Science.gov (United States)

Ohfuji, Hiroaki; Irifune, Tetsuo; Litasov, Konstantin D.; Yamashita, Tomoharu; Isobe, Futoshi; Afanasiev, Valentin P.; Pokhilenko, Nikolai P.

2015-10-01

Consolidated bodies of polycrystalline diamond with grain sizes less than 100 nm, nano-polycrystalline diamond (NPD), has been experimentally produced by direct conversion of graphite at high pressure and high temperature. NPD has superior hardness, toughness and wear resistance to single-crystalline diamonds because of its peculiar nano-textures, and has been successfully used for industrial and scientific applications. Such sintered nanodiamonds have, however, not been found in natural mantle diamonds. Here we identified natural pure NPD, which was produced by a large meteoritic impact about 35 Ma ago in Russia. The impact diamonds consist of well-sintered equigranular nanocrystals (5-50 nm), similar to synthetic NPD, but with distinct [111] preferred orientation. They formed through the martensitic transformation from single-crystal graphite. Stress-induced local fragmentation of the source graphite and subsequent rapid transformation to diamond in the limited time scale result in multiple diamond nucleation and suppression of the overall grain growth, producing the unique nanocrystalline texture of natural NPD. A huge amount of natural NPD is expected to be present in the Popigai crater, which is potentially important for applications as novel ultra-hard material.

Thermoluminescent properties of CVD diamond: applications to ionising radiation dosimetry

International Nuclear Information System (INIS)

Petitfils, A.

2007-09-01

Remarkable properties of synthetic diamond (human soft tissue equivalence, chemical stability, non-toxicity) make this material suitable for medical application as thermoluminescent dosimeter (TLD). This work highlights the interest of this material as radiotherapy TLD. In the first stage of this work, we looked after thermoluminescent (TL) and dosimetric properties of polycrystalline diamond made by Chemically Vapor Deposited (CVD) synthesis. Dosimetric characteristics are satisfactory as TLD for medical application. Luminescence thermal quenching on diamond has been investigated. This phenomenon leads to a decrease of dosimetric TL peak sensitivity when the heating rate increases. The second part of this work analyses the use of synthetic diamond as TLD in radiotherapy. Dose profiles, depth dose distributions and the cartography of an electron beam obtained with our samples are in very good agreement with results from an ionisation chamber. It is clearly shown that CVD) diamond is of interest to check beams of treatment accelerators. The use of these samples in a control of treatment with Intensity Modulated Radiation Therapy underlines good response of synthetic diamond in high dose gradient areas. These results indicate that CVD diamond is a promising material for radiotherapy dosimetry. (author)

Enamel subsurface damage due to tooth preparation with diamonds.

Science.gov (United States)

Xu, H H; Kelly, J R; Jahanmir, S; Thompson, V P; Rekow, E D

1997-10-01

In clinical tooth preparation with diamond burs, sharp diamond particles indent and scratch the enamel, causing material removal. Such operations may produce subsurface damage in enamel. However, little information is available on the mechanisms and the extent of subsurface damage in enamel produced during clinical tooth preparation. The aim of this study, therefore, was to investigate the mechanisms of subsurface damage produced in enamel during tooth preparation by means of diamond burs, and to examine the dependence of such damage on enamel rod orientation, diamond particle size, and removal rate. Subsurface damage was evaluated by a bonded-interface technique. Tooth preparation was carried out on two enamel rod orientations, with four clinical diamond burs (coarse, medium, fine, and superfine) used in a dental handpiece. The results of this study showed that subsurface damage in enamel took the form of median-type cracks and distributed microcracks, extending preferentially along the boundaries between the enamel rods. Microcracks within individual enamel rods were also observed. The median-type cracks were significantly longer in the direction parallel to the enamel rods than perpendicular to the rods. Preparation with the coarse diamond bur produced cracks as deep as 84 +/- 30 microns in enamel. Finishing with fine diamond burs was effective in crack removal. The crack lengths in enamel were not significantly different when the removal rate was varied. Based on these results, it is concluded that subsurface damage in enamel induced by tooth preparation takes the form of median-type cracks as well as inter- and intra-rod microcracks, and that the lengths of these cracks are sensitive to diamond particle size and enamel rod orientation, but insensitive to removal rate.

Kõik, mis teen, see kaob : lavastuskunstnik / Peter Schubert ; interv. Eero Epner

Index Scriptorium Estoniae

Schubert, Peter

2005-01-01

Intervjuu saksa lavastuskunstniku Peter Schubertiga, kes töötab põhikohaga lavastus- ja kostüümikunsti professorina Kunsthochschule Berlin-Weissensees. Lavakujunduse juurde jõudmisest, lavastuskunstnike ettevalmistamisest, lavastuskunsti rollist, "pildist" ehk optilisest üldmuljest, oma tööviisist, lavastaja ja kunstniku koostööst Saksamaal jm.

Globalisation in Africa: Reflecting on Peter Jarvis's Superstructure and Substructure Model

Science.gov (United States)

Preece, Julia

2017-01-01

This paper reflects on Peter Jarvis' book "Globalisation, lifelong learning and the learning society," volume 2--in which he describes human learning within a global context and factors contributing to globalisation. He describes the relationship of power between countries manifested as the superstructure and sub structure. The paper…

FEM thermal and stress analysis of bonded GaN-on-diamond substrate

Science.gov (United States)

Zhai, Wenbo; Zhang, Jingwen; Chen, Xudong; Bu, Renan; Wang, Hongxing; Hou, Xun

2017-09-01

A three-dimensional thermal and stress analysis of bonded GaN on diamond substrate is investigated using finite element method. The transition layer thickness, thermal conductivity of transition layer, diamond substrate thickness and the area ratio of diamond and GaN are considered and treated appropriately in the numerical simulation. The maximum channel temperature of GaN is set as a constant value and its corresponding heat power densities under different conditions are calculated to evaluate the influences that the diamond substrate and transition layer have on GaN. The results indicate the existence of transition layer will result in a decrease in the heat power density and the thickness and area of diamond substrate have certain impact on the magnitude of channel temperature and stress distribution. Channel temperature reduces with increasing diamond thickness but with a decreasing trend. The stress is reduced by increasing diamond thickness and the area ratio of diamond and GaN. The study of mechanical and thermal properties of bonded GaN on diamond substrate is useful for optimal designs of efficient heat spreader for GaN HEMT.

Tribological wear behavior of diamond reinforced composite coating

International Nuclear Information System (INIS)

Venkateswarlu, K.; Ray, Ajoy Kumar; Gunjan, Manoj Kumar; Mondal, D.P.; Pathak, L.C.

2006-01-01

In the present study, diamond reinforced composite (DRC) coating has been applied on mild steel substrate using thermal spray coating technique. The composite powder consists of diamond, tungsten carbide, and bronze, which was mixed in a ball mill prior deposition by thermal spray. The microstructure and the distribution of diamond and tungsten carbide particle in the bronze matrix were studied. The DRC-coated mild steel substrates were assessed in terms of their high stress abrasive wear and compared with that of uncoated mild steel substrates. It was observed that when sliding against steel, the DRC-coated sample initially gains weight, but then loses the transferred counter surface material. In case of abrasive wear, the wear rate was greatly reduced due to the coating; wherein the wear rate decreased with increase in diamond content

Diamond exploration and mantle structure imaging using PIXE microanalysis

Energy Technology Data Exchange (ETDEWEB)

Ryan, C G; Griffin, W L; Win, T T [Commonwealth Scientific and Industrial Research Organisation (CSIRO), North Ryde, NSW (Australia). Div. of Exploration Geoscience

1997-12-31

Geochemical methods of diamond exploration rely on recognizing indicator minerals that formed in the earth`s upper mantle, within the diamond stability field, and were entrained in rapidly rising volatile-rich magmas and emplaced in or on the crust. Diamond is only stable at high pressure. Therefore, diamond exploration commonly targets prospects containing high pressure minerals, such as low-Ca, high-Cr (`G10`) garnets and high-Cr chromites, similar to inclusions in diamonds. However, this procedure can be ambiguous; some barren pipes contain abundant `G10` garnets. while such garnets are extremely rare in the Argyle pipe, the world`s largest diamond producer. Similarly, high-Cr chromites are shed by a wide variety of barren rock types. PIXE microanalysis of trace elements in concentrate garnets and chromites from kimberlites and other volcanic rocks helps to remove the ambiguities by pinning down the source temperature (T), pressure (P) and local (paleo)geotherm (P-T relation), which permits the rich store of trace element information in these minerals, reflecting rock chemistry and metasomatic processes, to be placed in a stratigraphic context. 11 refs., 4 figs.

Diamond exploration and mantle structure imaging using PIXE microanalysis

Energy Technology Data Exchange (ETDEWEB)

Ryan, C.G.; Griffin, W.L.; Win, T.T. [Commonwealth Scientific and Industrial Research Organisation (CSIRO), North Ryde, NSW (Australia). Div. of Exploration Geoscience

1996-12-31

Geochemical methods of diamond exploration rely on recognizing indicator minerals that formed in the earth`s upper mantle, within the diamond stability field, and were entrained in rapidly rising volatile-rich magmas and emplaced in or on the crust. Diamond is only stable at high pressure. Therefore, diamond exploration commonly targets prospects containing high pressure minerals, such as low-Ca, high-Cr (`G10`) garnets and high-Cr chromites, similar to inclusions in diamonds. However, this procedure can be ambiguous; some barren pipes contain abundant `G10` garnets. while such garnets are extremely rare in the Argyle pipe, the world`s largest diamond producer. Similarly, high-Cr chromites are shed by a wide variety of barren rock types. PIXE microanalysis of trace elements in concentrate garnets and chromites from kimberlites and other volcanic rocks helps to remove the ambiguities by pinning down the source temperature (T), pressure (P) and local (paleo)geotherm (P-T relation), which permits the rich store of trace element information in these minerals, reflecting rock chemistry and metasomatic processes, to be placed in a stratigraphic context. 11 refs., 4 figs.

Recent results with CVD diamond trackers

Energy Technology Data Exchange (ETDEWEB)

Adam, W.; Bauer, C.; Berdermann, E.; Bergonzo, P.; Bogani, F.; Borchi, E.; Brambilla, A.; Bruzzi, M.; Colledani, C.; Conway, J.; Dabrowski, W.; Delpierre, P.; Deneuville, A.; Dulinski, W.; Eijk, B. van; Fallou, A.; Fizzotti, F.; Foulon, F.; Friedl, M.; Gan, K.K.; Gheeraert, E.; Grigoriev, E.; Hallewell, G.; Hall-Wilton, R.; Han, S.; Hartjes, F.; Hrubec, J.; Husson, D.; Kagan, H.; Kania, D.; Kaplon, J.; Karl, C.; Kass, R.; Knoepfle, K.T.; Krammer, M.; Logiudice, A.; Lu, R.; Manfredi, P.F.; Manfredotti, C.; Marshall, R.D.; Meier, D.; Mishina, M.; Oh, A.; Pan, L.S.; Palmieri, V.G.; Pernicka, M.; Peitz, A.; Pirollo, S.; Polesello, P.; Pretzl, K.; Procario, M.; Re, V.; Riester, J.L.; Roe, S.; Roff, D.; Rudge, A.; Runolfsson, O.; Russ, J.; Schnetzer, S.; Sciortino, S.; Speziali, V.; Stelzer, H.; Stone, R.; Suter, B.; Tapper, R.J.; Tesarek, R.; Trawick, M.; Trischuk, W.; Vittone, E.; Walsh, A.M.; Wedenig, R.; Weilhammer, P.; White, C.; Ziock, H.; Zoeller, M

1999-08-01

We present recent results on the use of Chemical Vapor Deposition (CVD) diamond microstrip detectors for charged particle tracking. A series of detectors was fabricated using 1 x 1 cm{sup 2} diamonds. Good signal-to-noise ratios were observed using both slow and fast readout electronics. For slow readout electronics, 2 {mu}s shaping time, the most probable signal-to-noise ratio was 50 to 1. For fast readout electronics, 25 ns peaking time, the most probable signal-to-noise ratio was 7 to 1. Using the first 2 x 4 cm{sup 2} diamond from a production CVD reactor with slow readout electronics, the most probable signal-to-noise ratio was 23 to 1. The spatial resolution achieved for the detectors was consistent with the digital resolution expected from the detector pitch.

Recent results with CVD diamond trackers

CERN Document Server

Adam, W; Berdermann, E; Bergonzo, P; Bogani, F; Borchi, E; Brambilla, A; Bruzzi, Mara; Colledani, C; Conway, J; Dabrowski, W; Delpierre, P A; Deneuville, A; Dulinski, W; van Eijk, B; Fallou, A; Fizzotti, F; Foulon, F; Friedl, M; Gan, K K; Gheeraert, E; Grigoriev, E; Hallewell, G D; Hall-Wilton, R; Han, S; Hartjes, F G; Hrubec, Josef; Husson, D; Kagan, H; Kania, D R; Kaplon, J; Karl, C; Kass, R; Knöpfle, K T; Krammer, Manfred; Lo Giudice, A; Lü, R; Manfredi, P F; Manfredotti, C; Marshall, R D; Meier, D; Mishina, M; Oh, A; Pan, L S; Palmieri, V G; Pernicka, Manfred; Peitz, A; Pirollo, S; Polesello, P; Pretzl, Klaus P; Procario, M; Re, V; Riester, J L; Roe, S; Roff, D G; Rudge, A; Runólfsson, O; Russ, J; Schnetzer, S R; Sciortino, S; Speziali, V; Stelzer, H; Stone, R; Suter, B; Tapper, R J; Tesarek, R J; Trawick, M L; Trischuk, W; Vittone, E; Walsh, A M; Wedenig, R; Weilhammer, Peter; White, C; Ziock, H J; Zöller, M

1999-01-01

We present recent results on the use of chemical vapor deposition (CVD) diamond microstrip detectors for charged particle tracking. A series of detectors was fabricated using 1*1 cm/sup 2/ diamonds. Good signal-to-noise ratios were observed using both slow and fast readout electronics. For slow readout electronics, 2 mu s shaping time, the most probable signal-to-noise ratio was 50 to 1. For fast readout electronics, 25 ns peaking time, the most probable signal-to-noise ratio was 7 to 1. Using the first 2*4 cm/sup 2/ diamond from a production CVD reactor with slow readout electronics, the most probable signal-to-noise ratio was 23 to 1. The spatial resolution achieved for the detectors was consistent with the digital resolution expected from the detector pitch. (6 refs).

Computational assignment of redox states to Coulomb blockade diamonds.

Science.gov (United States)

Olsen, Stine T; Arcisauskaite, Vaida; Hansen, Thorsten; Kongsted, Jacob; Mikkelsen, Kurt V

2014-09-07

With the advent of molecular transistors, electrochemistry can now be studied at the single-molecule level. Experimentally, the redox chemistry of the molecule manifests itself as features in the observed Coulomb blockade diamonds. We present a simple theoretical method for explicit construction of the Coulomb blockade diamonds of a molecule. A combined quantum mechanical/molecular mechanical method is invoked to calculate redox energies and polarizabilities of the molecules, including the screening effect of the metal leads. This direct approach circumvents the need for explicit modelling of the gate electrode. From the calculated parameters the Coulomb blockade diamonds are constructed using simple theory. We offer a theoretical tool for assignment of Coulomb blockade diamonds to specific redox states in particular, and a study of chemical details in the diamonds in general. With the ongoing experimental developments in molecular transistor experiments, our tool could find use in molecular electronics, electrochemistry, and electrocatalysis.

THE TRADITIONS OF ERMOLAY-ERAZMUS'S "THE TALE OF PETER AND FEVRONIA" IN ALEXANDER PUSHKIN'S NOVEL "THE CAPTAIN'S DAUGHTER"

Directory of Open Access Journals (Sweden)

Natalya Gennadievna Komar

2013-11-01

Full Text Available This article raises the question of the Old Russian sources of Alexander Pushkin’s novel The Captain’s Daughter and presents an attempt to identify the traditions of Ermolay-Erazmus’s The Tale of Peter and Fevronia in it. The main purpose of the research was to identify the parallelism between Pushkin’s novel and The Tale at the imaginative, narrative and thematic levels. Therefore, it was based on application of the comparative method. The main characters of both the books are compared in succession: Prince Peter and Peter Grinyov first, and then Fevronia and Masha Mironova. The results of the analysis lead to the conclusion that the male images reflect the spiritual evolution from being self-willed to obtaining Christian humility, and the key moment of the characters’ spiritual evolution is the meeting with wise virgins, etc. As far as the female images are concerned, the key parallel between them is the praise of their wisdom at the end of both stories. Thus, the material of the research enables us to speak about the traditions of The Tale of Peter and Fevronia being preserved in Pushkin’s last novel.

High-Q/V Monolithic Diamond Microdisks Fabricated with Quasi-isotropic Etching.

Science.gov (United States)

Khanaliloo, Behzad; Mitchell, Matthew; Hryciw, Aaron C; Barclay, Paul E

2015-08-12

Optical microcavities enhance light-matter interactions and are essential for many experiments in solid state quantum optics, optomechanics, and nonlinear optics. Single crystal diamond microcavities are particularly sought after for applications involving diamond quantum emitters, such as nitrogen vacancy centers, and for experiments that benefit from diamond's excellent optical and mechanical properties. Light-matter coupling rates in experiments involving microcavities typically scale with Q/V, where Q and V are the microcavity quality-factor and mode-volume, respectively. Here we demonstrate that microdisk whispering gallery mode cavities with high Q/V can be fabricated directly from bulk single crystal diamond. By using a quasi-isotropic oxygen plasma to etch along diamond crystal planes and undercut passivated diamond structures, we create monolithic diamond microdisks. Fiber taper based measurements show that these devices support TE- and TM-like optical modes with Q > 1.1 × 10(5) and V < 11(λ/n) (3) at a wavelength of 1.5 μm.

Robust diamond meshes with unique wettability properties.

Science.gov (United States)

Yang, Yizhou; Li, Hongdong; Cheng, Shaoheng; Zou, Guangtian; Wang, Chuanxi; Lin, Quan

2014-03-18

Robust diamond meshes with excellent superhydrophobic and superoleophilic properties have been fabricated. Superhydrophobicity is observed for water with varying pH from 1 to 14 with good recyclability. Reversible superhydrophobicity and hydrophilicity can be easily controlled. The diamond meshes show highly efficient water-oil separation and water pH droplet transference.

Growth, characterization, and device development in monocrystalline diamond films

Science.gov (United States)

Davis, Robert F.

1991-12-01

The nucleation of diamond grains on an unscratched silicon wafer is enhanced by four order of magnitude relative to scratched substrates by using negative bias enhanced microwave plasma CVD in a 2 percent methane/hydrogen plasma for an initial period. In vacuo surface analysis has revealed that the actual nucleation occurs on the amorphous C coating present on the thin SiC layer which forms as the product of the initial reaction with the Si surface. It is believed that the C forms critical clusters which are favorable for diamond nucleation. Similar enhancement was observed together with the occurrence of textured diamond films in the use of bias pretreatment of cubic Beta SiC substrates. Approximately 50 percent of the initial diamond nuclei were aligned with the SiC substrate. In contrast, the use of the biasing pretreatment for one hour on polycrystalline substrates resulted in only about 7 percent coverage with diamond particles. Numerous techniques have been used to analyze the nucleation and growth phenomena, especially micro Raman and scanning tunneling microscopy. The latter technique has shown that the morphology of doped and undoped diamond nuclei are similar, as well as the fact that significant concentrations of vacancy related defects are present. In device related-studies, UV-photoemission studies have shown that TiC occurs at the Ti-diamond (100) interface after a 400 C anneal. The Schottky barrier height from this metal on p-type diamond was determined to be 1.0 eV. Indications of negative electron affinity (NEA) was observed and attributed to emission of electrons that are quasi-thermalized to the bottom of the conduction band. A disordered surface removes the NEA. The microwave performance of p-type (beta-doped) diamond MESFET's at 10 GHz has been further investigated. Elevated temperatures may be necessary to obtain sufficient free charge densities in the conducting channel but this will result in degraded device performance. Each of these

Diamond electro-optomechanical resonators integrated in nanophotonic circuits

Energy Technology Data Exchange (ETDEWEB)

Rath, P.; Ummethala, S.; Pernice, W. H. P., E-mail: wolfram.pernice@kit.edu [Institute of Nanotechnology, Karlsruhe Institute of Technology, 76344 Eggenstein-Leopoldshafen (Germany); Diewald, S. [Center for Functional Nanostructures, Karlsruhe Institute of Technology, 76131 Karlsruhe (Germany); Lewes-Malandrakis, G.; Brink, D.; Heidrich, N.; Nebel, C. [Fraunhofer Institute for Applied Solid State Physics, Tullastr. 72, 79108 Freiburg (Germany)

2014-12-22

Diamond integrated photonic devices are promising candidates for emerging applications in nanophotonics and quantum optics. Here, we demonstrate active modulation of diamond nanophotonic circuits by exploiting mechanical degrees of freedom in free-standing diamond electro-optomechanical resonators. We obtain high quality factors up to 9600, allowing us to read out the driven nanomechanical response with integrated optical interferometers with high sensitivity. We are able to excite higher order mechanical modes up to 115 MHz and observe the nanomechanical response also under ambient conditions.

Status of the R&D activity on diamond particle detectors

Science.gov (United States)

Adam, W.; Bellini, B.; Berdermann, E.; Bergonzo, P.; de Boer, W.; Bogani, F.; Borchi, E.; Brambilla, A.; Bruzzi, M.; Colledani, C.; Conway, J.; D'Angelo, P.; Dabrowski, W.; Delpierre, P.; Doroshenko, J.; Dulinski, W.; van Eijk, B.; Fallou, A.; Fischer, P.; Fizzotti, F.; Furetta, C.; Gan, K. K.; Ghodbane, N.; Grigoriev, E.; Hallewell, G.; Han, S.; Hartjes, F.; Hrubec, J.; Husson, D.; Kagan, H.; Kaplon, J.; Karl, C.; Kass, R.; Keil, M.; Knöpfle, K. T.; Koeth, T.; Krammer, M.; Logiudice, A.; Lu, R.; mac Lynne, L.; Manfredotti, C.; Marshall, R. D.; Meier, D.; Menichelli, D.; Meuser, S.; Mishina, M.; Moroni, L.; Noomen, J.; Oh, A.; Perera, L.; Pernicka, M.; Polesello, P.; Potenza, R.; Riester, J. L.; Roe, S.; Rudge, A.; Sala, S.; Sampietro, M.; Schnetzer, S.; Sciortino, S.; Stelzer, H.; Stone, R.; Sutera, C.; Trischuk, W.; Tromson, D.; Tuve, C.; Weilhammer, P.; Wermes, N.; Wetstein, M.; Zeuner, W.; Zoeller, M.; RD42 Collaboration

2003-09-01

Chemical Vapor Deposited (CVD) polycrystalline diamond has been proposed as a radiation-hard alternative to silicon in the extreme radiation levels occurring close to the interaction region of the Large Hadron Collider. Due to an intense research effort, reliable high-quality polycrystalline CVD diamond detectors, with up to 270 μm charge collection distance and good spatial uniformity, are now available. The most recent progress on the diamond quality, on the development of diamond trackers and on radiation hardness studies are presented and discussed.

Idiopathic inflammatory myopathies in adults: A comparative study of Bohan and Peter and European Neuromuscular Center 2004 criteria.

Science.gov (United States)

Challa, Sundaram; Jakati, Saumya; Uppin, Megha S; Kannan, Meena A; Liza, Rajasekhar; Murthy Jagarlapudi, M K

2018-01-01

Bohan and Peter criteria are widely used for the diagnosis of idiopathic inflammatory myopathies (IIMs). Recently, European Neuromuscular Center (ENMC) formulated criteria to identify subgroups of IIMs. To compare the two diagnostic criteria in adult IIMs. This was a retrospective review of case records of histologically confirmed IIMs in adults between January 2014 and May 2015. Both the Bohan and Peter, and ENMC 2004 criteria were applied in the same group of patients to subgroup the IIMs. Muscle biopsy was evaluated in all the four domains: muscle fiber, inflammatory, connective tissue, and vascular, with the basic panel of histological stains. Sporadic inclusion body myositis (s-IBM) was diagnosed using ENMC IBM diagnostic research criteria 2011. During the study period, 69 patients fulfilled the ENMC criteria for IIMs including 16 patients with s-IBM. The subgrouping as per the ENMC criteria (53) was: dermatomyositis (DM) in 30; polymyositis (PM) in 2; immune-mediated necrotizing myopathy (IMNM) in 9; and nonspecific myositis (NM) in 12 patients, whereas subgrouping by the Bohan and Peter criteria was DM in 9 and PM with and without connective tissue disease (CTD) in 26 patients only. There was underdiagnosis of DM, as perifascicular atrophy is not recognized as a diagnostic histological feature, and overdiagnosis of PM with and without CTD due to poor characterization of histological features in PM by the Bohan and Peter criteria. Systematic evaluation of muscle biopsy according to the ENMC criteria with basic panel of histochemical stains improved the diagnostic yield of IIM significantly when compared to the Bohan and Peter criteria.

Friction Properties of Polished Cvd Diamond Films Sliding against Different Metals

Science.gov (United States)

Lin, Zichao; Sun, Fanghong; Shen, Bin

2016-11-01

Owing to their excellent mechanical and tribological properties, like the well-known extreme hardness, low coefficient of friction and high chemical inertness, chemical vapor deposition (CVD) diamond films have found applications as a hard coating for drawing dies. The surface roughness of the diamond films is one of the most important attributes to the drawing dies. In this paper, the effects of different surface roughnesses on the friction properties of diamond films have been experimentally studied. Diamond films were fabricated using hot filament CVD. The WC-Co (Co 6wt.%) drawing dies were used as substrates. A gas mixture of acetone and hydrogen gas was used as the feedstock gas. The CVD diamond films were polished using mechanical polishing. Polished diamond films with three different surface roughnesses, as well as the unpolished diamond film, were fabricated in order to study the tribological performance between the CVD diamond films and different metals with oil lubrication. The unpolished and polished CVD diamond films are characterized with scanning electron microscope (SEM), atomic force microscope (AFM), surface profilometer, Raman spectrum and X-ray diffraction (XRD). The friction examinations were carried out by using a ball-on-plate type reciprocating friction tester. Low carbide steel, stainless steel, copper and aluminum materials were used as counterpart balls. Based on this study, the results presented the friction coefficients between the polished CVD films and different metals. The friction tests demonstrate that the smooth surface finish of CVD diamond films is beneficial for reducing their friction coefficients. The diamond films exhibit low friction coefficients when slid against the stainless steel balls and low carbide steel ball, lower than that slid against copper ball and aluminum ball, attributed to the higher ductility of copper and aluminum causing larger amount of wear debris adhering to the sliding interface and higher adhesive

Takashi Murakami ja Peter Doigi suurnäitus Frankfurdis / Jaan Elken

Index Scriptorium Estoniae

Elken, Jaan, 1954-

2008-01-01

Kuni 4. I 2009 Frankfurdi moodsa kunsti muuseumis avatud jaapani kunstniku Takashi Murakami (sünd. 1962) personaalnäitusest ning Shirni kunsthallis avatud inglise kunstniku Peter Doigi (sünd. 1959) maalinäitusest ja lühidalt Rene Magritte'i 1948. a. näituse "La Periode Vache" rekonstruktsioonist

The Peter Effect Revisited: Reading Habits and Attitudes of College Students

Science.gov (United States)

Applegate, Anthony J.; Applegate, Mary DeKonty; Mercantini, Martha A.; McGeehan, Catherine M.; Cobb, Jeanne B.; DeBoy, Joanne R.; Modla, Virginia B.; Lewinski, Kimberly E.

2014-01-01

Certainly a primary goal of literacy education is the creation of avid, enthusiastic, and highly motivated readers. However, in this article revisiting the Peter Effect (Applegate & Applegate, 2004), researchers surveyed more than 1,000 college sophomores and found strikingly low levels of enthusiasm for reading. Only 46.6% of surveyed…

Radiation hard 3D diamond sensors for vertex detectors at HL-LHC

CERN Document Server

AUTHOR|(INSPIRE)INSPIRE-00336619; Quadt, Arnulf; Grosse-Knetter, Jörn; Weingarten, Jens

Diamond is a good candidate to replace silicon as sensor material in the innermost layer of a tracking detector at HL-LHC, due to its high radiation tolerance. After particle fluences of $10^{16}\\,{\\rm protons/cm^2}$, diamond sensors are expected to achieve a higher signal to noise ratio than silicon. In order to use low grade polycrystalline diamonds as sensors, electrodes inside the diamond bulk, so called 3D electrodes, are produced. Typically, this kind of diamond material has a lower charge collection distance (CCD) than higher grade diamond, which results in a decreased signal amplitude. With 3D electrodes it is possible to achieve full charge collection even in samples with low CCDs by decoupling the spacing of the electrodes from the thickness of the diamond bulk. The electrodes are produced using a femtosecond laser, which changes the phase of the diamond material. The phase changed material is conductive and identified as nanocrystalline graphite using Raman spectroscopy. Due to a crater like struct...

Free-standing nanomechanical and nanophotonic structures in single-crystal diamond

Science.gov (United States)

Burek, Michael John

Realizing complex three-dimensional structures in a range of material systems is critical to a variety of emerging nanotechnologies. This is particularly true of nanomechanical and nanophotonic systems, both relying on free-standing small-scale components. In the case of nanomechanics, necessary mechanical degrees of freedom require physically isolated structures, such as suspended beams, cantilevers, and membranes. For nanophotonics, elements like waveguides and photonic crystal cavities rely on light confinement provided by total internal reflection or distributed Bragg reflection, both of which require refractive index contrast between the device and surrounding medium (often air). Such suspended nanostructures are typically fabricated in a heterolayer structure, comprising of device (top) and sacrificial (middle) layers supported by a substrate (bottom), using standard surface nanomachining techniques. A selective, isotropic etch is then used to remove the sacrificial layer, resulting in free-standing devices. While high-quality, crystalline, thin film heterolayer structures are readily available for silicon (as silicon-on-insulator (SOI)) or III-V semiconductors (i.e. GaAs/AlGaAs), there remains an extensive list of materials with attractive electro-optic, piezoelectric, quantum optical, and other properties for which high quality single-crystal thin film heterolayer structures are not available. These include complex metal oxides like lithium niobate (LiNbO3), silicon-based compounds such as silicon carbide (SiC), III-V nitrides including gallium nitride (GaN), and inert single-crystals such as diamond. Diamond is especially attractive for a variety of nanoscale technologies due to its exceptional physical and chemical properties, including high mechanical hardness, stiffness, and thermal conductivity. Optically, it is transparent over a wide wavelength range (from 220 nm to the far infrared), has a high refractive index (n ~ 2.4), and is host to a vast

Functionalized diamond nanopowder for phosphopeptides enrichment from complex biological fluids

Energy Technology Data Exchange (ETDEWEB)

Hussain, Dilshad [Division of Analytical Chemistry, Institute of Chemical Sciences, Bahauddin Zakariya University, Multan 60800 (Pakistan); Najam-ul-Haq, Muhammad, E-mail: najamulhaq@bzu.edu.pk [Division of Analytical Chemistry, Institute of Chemical Sciences, Bahauddin Zakariya University, Multan 60800 (Pakistan); Institute of Analytical Chemistry and Radiochemistry, Leopold-Franzens University, Innrain 80-82, A-6020 Innsbruck (Austria); Jabeen, Fahmida; Ashiq, Muhammad N.; Athar, Muhammad [Division of Analytical Chemistry, Institute of Chemical Sciences, Bahauddin Zakariya University, Multan 60800 (Pakistan); Rainer, Matthias; Huck, Christian W.; Bonn, Guenther K. [Institute of Analytical Chemistry and Radiochemistry, Leopold-Franzens University, Innrain 80-82, A-6020 Innsbruck (Austria)

2013-05-02

Graphical abstract: -- Highlights: •Derivatization of diamond nanopowder as IMAC and RP. •Characterization with SEM, EDX and FT-IR. •Phosphopeptide enrichment from standard as well as real samples. •Desalting and human serum profiling with reproducible results. •MALDI-MS analysis with database identification. -- Abstract: Diamond is known for its high affinity and biocompatibility towards biomolecules and is used exclusively in separation sciences and life science research. In present study, diamond nanopowder is derivatized as Immobilized Metal Ion Affinity Chromatographic (IMAC) material for the phosphopeptides enrichment and as Reversed Phase (C-18) media for the desalting of complex mixtures and human serum profiling through MALDI-TOF-MS. Functionalized diamond nanopowder is characterized by Fourier transform infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) spectroscopy. Diamond-IMAC is applied to the standard protein (β-casein), spiked human serum, egg yolk and non-fat milk for the phosphopeptides enrichment. Results show the selectivity of synthesized IMAC-diamond immobilized with Fe{sup 3+} and La{sup 3+} ions. To comprehend the elaborated use, diamond-IMAC is also applied to the serum samples from gall bladder carcinoma for the potential biomarkers. Database search is carried out by the Mascot program ( (www.matrixscience.com)) for the assignment of phosphorylation sites. Diamond nanopowder is thus a separation media with multifunctional use and can be applied to cancer protein profiling for the diagnosis and biomarker identification.

CVD diamonds as thermoluminescent detectors for medical applications

International Nuclear Information System (INIS)

Marczewska, B.; Olko, P.; Nesladek, M.; Waligorski, M.P.R.; Kerremans, Y.

2002-01-01

Diamond is believed to be a promising material for medical dosimetry due to its tissue equivalence, mechanical and radiation hardness, and lack of solubility in water or in disinfecting agents. A number of diamond samples, obtained under different growth conditions at Limburg University, using the chemical vapour deposition (CVD) technique, was tested as thermoluminescence dosemeters. Their TL glow curve, TL response after doses of gamma rays, fading, and so on were studied at dose levels and for radiation modalities typical for radiotherapy. The investigated CVD diamonds displayed sensitivity comparable with that of MTS-N (Li:Mg,Ti) detectors, signal stability (reproducibility after several readouts) below 10% (1 SD) and no fading was found four days after irradiation. A dedicated CVD diamond plate was grown, cut into 20 detector chips (3x3x0.5 mm) and used for measuring the dose-depth distribution at different depths in a water phantom, for 60 Co and six MV X ray radiotherapy beams. Due to the sensitivity of diamond to ambient light, it was difficult to achieve reproducibility comparable with that of standard LiF detectors. (author)

Adhesive wear mechanism under combined electric diamond grinding

Directory of Open Access Journals (Sweden)

Popov Vyacheslav

2017-01-01

Full Text Available The article provides a scientific substantiation of loading of metal-bond diamond grinding wheels and describes the mechanism of contact interaction (interlocking of wheels with tool steel as well as its general properties having an influence on combined electric diamond grinding efficiency. The study concluded that a loaded layer can be formed in a few stages different by nature. It is known, that one of the causes of grinding degradation is a continuous loading of active grits (abrasive grinding tool by workpiece chips. It all affects the diamond grinding wheels efficiency and grinding ability with a result in increase of tool pressure, contact temperature and wheels specific removal rate. Science has partially identified some various methods to minimize grinding wheel loading, however, as to loading of metal-bond diamond grinding wheels the search is still in progress. Therefore, research people have to state, that in spite of the fact that the wheels made of cubic boron nitride are of little use as applied to ceramic, ultrahard, hard-alloyed hard-to-machine and nano-materials of the time, but manufactures have to apply cubic boron nitride wheels wherein diamond ones preferable.

Spallation Neutron Source SNS Diamond Stripper Foil Development

International Nuclear Information System (INIS)

Shaw, Robert W.; Plum, Michael A.; Wilson, Leslie L.; Feigerle, Charles S.; Borden, Michael J.; Irie, Y.; Sugai, I.; Takagi, A.

2007-01-01

Diamond stripping foils are under development for the SNS. Freestanding, flat 300 to 500 (micro)g/cm 2 foils as large as 17 x 25 mm 2 have been prepared. These nano-textured polycrystalline foils are grown by microwave plasma-assisted chemical vapor deposition in a corrugated format to maintain their flatness. They are mechanically supported on a single edge by a residual portion of their silicon growth substrate; fine foil supporting wires are not required for diamond foils. Six foils were mounted on the SNS foil changer in early 2006 and have performed well in commissioning experiments at reduced operating power. A diamond foil was used during a recent experiment where 15 (micro)C of protons, approximately 64% of the design value, were stored in the ring. A few diamond foils have been tested at LANSCE/PSR, where one foil was in service for a period of five months (820 C of integrated injected charge) before it was replaced. Diamond foils have also been tested in Japan at KEK (640 keV H - ) where their lifetimes slightly surpassed those of evaporated carbon foils, but fell short of those for Sugai's new hybrid boron carbon (HBC) foils.

Novel morphology of chemical vapor deposited diamond films

Energy Technology Data Exchange (ETDEWEB)

Tang, C.J. [I3N and Department of Physics, University of Aveiro (Portugal); Jiangsu Key Laboratory for Advanced Functional Materials and Department of Physics, Changshu Institute of Technology, Changshu (China); TEMA and Department of Mechanical Engineering, University of Aveiro (Portugal); Fernandes, A.J.S.; Abe, I.; Pinto, J.L. [I3N and Department of Physics, University of Aveiro (Portugal); Gracio, J. [TEMA and Department of Mechanical Engineering, University of Aveiro (Portugal); Buijnsters, J.G. [Institute for Molecules and Materials (IMM), Radboud University Nijmegen (Netherlands)

2010-04-15

We have obtained simultaneously nanocrystalline and {l_brace}100{r_brace} faceted large-grained polycrystalline diamond films not only on different substrates but also on the same substrate in only one deposition run using a novel approach for substrate arrangement. Furthermore, interesting unusual morphologies and microstructures composed by non-faceted nanostructures and terminated with large smooth {l_brace}100{r_brace} facet-like belt are found near the edges of the top square sample. The morphology variation is likely caused by the so called edge effect, where a strong variation in temperature is also present. We have modelled the temperature distribution on the substrates by computer simulations using the finite element method. The novel feature, namely the coexistence of oval non-faceted nanocrystalline diamond grains and large smooth {l_brace}100{r_brace} facet-like belt in one diamond grain, is in the transition from {l_brace}100{r_brace} faceted polycrystalline diamond to cauliflower-like nanocrystalline diamond. The formation mechanism is discussed based on the temperature analysis and other simulation results described in the literature. (copyright 2010 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

Growth, characterization and device development in monocrystalline diamond films

Science.gov (United States)

Davis, R. F.; Glass, J. T.; Nemanich, R. J.; Bozeman, S. P.; Sowers, A. T.

1995-06-01

Experimental and theoretical studies concerned with interface interactions of diamond with Si, Ni, and Ni3Si substrates have been conducted. Oriented diamond films deposited on (100) Si were characterized by polar Raman, polar x-ray diffraction (XRD), and cross-sectional high resolution transmission electron microscopy (HRTEM). These sutides showed that the diamond(100)/Si(100) interface adopted the 3:2-match arrangement rather than a 45 deg rotation. Extended Hueckel tight-binding (EHTB) electronic structure calculations for a model system revealed that the interface interaction favors the 3:2-match arrangement. Growth on polycrystalline Ni3Si resulted in oriented diamond particles; under the same growth conditions, graphite was formed on the nickel substrate. Our EHTB electronic structure calculations showed that the (111) and (100) surfaces of Ni3Si have a strong preference for diamond nucleation over graphite nucleation, but this was not the case for the (111) and (100) surfaces of Ni.

Diamond Windows for High Powered Microwave Transmission. Final Report

International Nuclear Information System (INIS)

Gat, R.

2011-01-01

This phase II SBIR developed technology for manufacturing diamond windows for use in high energy density photon transmission e.g. microwave or laser light photons. Microwave sources used in fusion research require microwave extraction windows with high thermal conductivity, low microwave absorption, and low resistance to thermal cracking. Newly developed, man made diamond windows have all three of these properties, but these windows are prohibitively expensive. This limits the natural progress of these important technologies to higher powers and slows the development of additional applications. This project developed a lower cost process for manufacturing diamond windows using microwave plasma. Diamond windows were deposited. A grinding process was used to provide optical smoothness for 2 cm diameter diamond windows that met the parallelism specifications for fusion beam windows. The microwave transmission performance (loss tangent) of one of the windows was measured at 95GHz to be less than 10-4, meeting specifications for utilization in the ITER tokamak.

Review: Plasma-enhanced chemical vapor deposition of nanocrystalline diamond

Directory of Open Access Journals (Sweden)

Katsuyuki Okada

2007-01-01

Full Text Available Nanocrystalline diamond films have attracted considerable attention because they have a low coefficient of friction and a low electron emission threshold voltage. In this paper, the author reviews the plasma-enhanced chemical vapor deposition (PE-CVD of nanocrystalline diamond and mainly focuses on the growth of nanocrystalline diamond by low-pressure PE-CVD. Nanocrystalline diamond particles of 200–700 nm diameter have been prepared in a 13.56 MHz low-pressure inductively coupled CH4/CO/H2 plasma. The bonding state of carbon atoms was investigated by ultraviolet-excited Raman spectroscopy. Electron energy loss spectroscopy identified sp2-bonded carbons around the 20–50 nm subgrains of nanocrystalline diamond particles. Plasma diagnostics using a Langmuir probe and the comparison with plasma simulation are also reviewed. The electron energy distribution functions are discussed by considering different inelastic interaction channels between electrons and heavy particles in a molecular CH4/H2 plasma.

Iron Oxide Nanoparticles Employed as Seeds for the Induction of Microcrystalline Diamond Synthesis

Directory of Open Access Journals (Sweden)

Resto Oscar

2008-01-01

Full Text Available AbstractIron nanoparticles were employed to induce the synthesis of diamond on molybdenum, silicon, and quartz substrates. Diamond films were grown using conventional conditions for diamond synthesis by hot filament chemical vapor deposition, except that dispersed iron oxide nanoparticles replaced the seeding. X-ray diffraction, visible, and ultraviolet Raman Spectroscopy, energy-filtered transmission electron microscopy , electron energy-loss spectroscopy, and X-ray photoelectron spectroscopy (XPS were employed to study the carbon bonding nature of the films and to analyze the carbon clustering around the seed nanoparticles leading to diamond synthesis. The results indicate that iron oxide nanoparticles lose the O atoms, becoming thus active C traps that induce the formation of a dense region of trigonally and tetrahedrally bonded carbon around them with the ensuing precipitation of diamond-type bonds that develop into microcrystalline diamond films under chemical vapor deposition conditions. This approach to diamond induction can be combined with dip pen nanolithography for the selective deposition of diamond and diamond patterning while avoiding surface damage associated to diamond-seeding methods.

X-ray studies of synthetic radiation-counting diamonds

Energy Technology Data Exchange (ETDEWEB)

Yacoot, Andrew; Moore, Moreton (Royal Holloway and Bedford New Coll., Egham (UK). Dept. of Physics); Makepeace, Anthony (Bristol Univ. (UK). Dept. of Physiology)

1990-10-01

Synthetic diamonds with a nitrogen content less than 100 ppm may be used as radiation dosemeters in a conduction counting mode, and are especially useful in medical applications. Crystal imperfections, revealed by x-ray diffraction topography, were found to affect counting performance. The best quality diamond gave the highest photocurrent (500 nA at 50 V mm{sup -1} and 2.75 Gy min{sup -1}). Diamonds containing dislocations had lower photocurrents but had the advantage of shorter settling times (seconds rather than minutes). Placing contacts on two opposite cube {l brace}100{r brace} faces gave a higher photocurrent than on a pair of octahedral {l brace}111{r brace} faces. Higher photocurrents were also achieved when the majority of dislocations were perpendicular rather than parallel, to the electric field. Some recommendations for selecting synthetic diamonds for dosemeters are given. (author).

Berger Peter L., Invitation à la sociologie

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Nicolas Marquis

2011-03-01

Full Text Available L’invitation à la sociologie de Peter Berger est la réédition d’un ouvrage initiale­ment paru en 1963. Né en 1929, P. Berger est un des grands noms de la sociologie amé­ricaine actuelle, notamment connu chez nous pour un ouvrage coécrit avec Th. Luck­­mann et paru trois ans après la première édition de Invitation à la sociologie : The Social Construction of Reality, qui constitue une étape importante dans l’approche dite du constructivisme social en réactivant la tradition phénoménologique en...

FEM thermal and stress analysis of bonded GaN-on-diamond substrate

Directory of Open Access Journals (Sweden)

Wenbo Zhai

2017-09-01

Full Text Available A three-dimensional thermal and stress analysis of bonded GaN on diamond substrate is investigated using finite element method. The transition layer thickness, thermal conductivity of transition layer, diamond substrate thickness and the area ratio of diamond and GaN are considered and treated appropriately in the numerical simulation. The maximum channel temperature of GaN is set as a constant value and its corresponding heat power densities under different conditions are calculated to evaluate the influences that the diamond substrate and transition layer have on GaN. The results indicate the existence of transition layer will result in a decrease in the heat power density and the thickness and area of diamond substrate have certain impact on the magnitude of channel temperature and stress distribution. Channel temperature reduces with increasing diamond thickness but with a decreasing trend. The stress is reduced by increasing diamond thickness and the area ratio of diamond and GaN. The study of mechanical and thermal properties of bonded GaN on diamond substrate is useful for optimal designs of efficient heat spreader for GaN HEMT.

Illumination-induced charge transfer in polypyrrole-diamond nanosystem

Czech Academy of Sciences Publication Activity Database

Čermák, Jan; Kromka, Alexander; Ledinský, Martin; Rezek, Bohuslav

2009-01-01

Roč. 18, 5-8 (2009), s. 800-803 ISSN 0925-9635. [European Conference on Diamond, Diamond-Like Materials, Carbon Nanotubes, Nitrides and Silicon Carbide /19./. Sitges, 07.09.2008-11.09.2008] R&D Projects: GA MŠk(CZ) LC06040; GA AV ČR KAN400100701; GA ČR(CZ) GD202/05/H003; GA MŠk LC510 Institutional research plan: CEZ:AV0Z10100521 Keywords : diamond * polymers * heterojunction * electronic transport Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 1.822, year: 2009

Nanocrystalline diamond coatings for cutting operations; Nanokristalline Diamantschichten fuer die Zerspanung

Energy Technology Data Exchange (ETDEWEB)

Frank, M.; Breidt, D.; Cremer, R. [CemeCon AG, Wuerselen (Germany). Technology

2006-06-15

The history of the CVD diamond synthesis goes back into the fifties. However, the scientific and economical potential was only gradually recognized. In the eighties intensive world-wide research on CVD diamond synthesis and applications were launched. Industrial products, especially diamond-coated cutting tools, were introduced to the market in the middle of the nineties. The article shows the latest developments in this area, which comprises nanocrystalline diamond coating structures. (orig.)

Optical properties of implanted Xe color centers in diamond

Science.gov (United States)

Sandstrom, Russell; Ke, Li; Martin, Aiden; Wang, Ziyu; Kianinia, Mehran; Green, Ben; Gao, Wei-bo; Aharonovich, Igor

2018-03-01

Optical properties of color centers in diamond have been the subject of intense research due to their promising applications in quantum photonics. In this work we study the optical properties of Xe related color centers implanted into nitrogen rich (type IIA) and an ultrapure, electronic grade diamond. The Xe defect has two zero phonon lines at ∼794 nm and 811 nm, which can be effectively excited using both green and red excitation, however, its emission in the nitrogen rich diamond is brighter. Near resonant excitation is performed at cryogenic temperatures and luminescence is probed under strong magnetic field. Our results are important towards the understanding of the Xe related defect and other near infrared color centers in diamond.

Assessment of CVD diamond as a thermoluminescence dosemeter material

International Nuclear Information System (INIS)

Borchi, E.; Furetta, C.; Leroy, C.

1996-01-01

Diamond has a low atomic number (Z = 6) and is therefore essentially soft tissue (Z = 7.4) equivalent. As such, diamond is an attractive material for applications in dosimetry in which the radiation absorption in the sensor material should be as close as possible to that of soft tissue. Synthetic diamond prepared by chemical vapour deposition (CVD) offers an attractive option for this application. The aim of the present work is to report results on the thermoluminescence (TL) properties of CVD diamond samples. The annealing procedures, the linearity of the TL response as a function of dose, a short-term fading experiment and some kinetic properties have been investigated and are reported here. (Author)

Peter Paul Rubens, Galileo Galilei und die Schlacht am Weißen Berg

Czech Academy of Sciences Publication Activity Database

Konečný, Lubomír

2005-01-01

Roč. 26, č. 52 (2005), s. 85-91 ISSN 0391-9064 Institutional research plan: CEZ:AV0Z80330511 Keywords : Peter Paul Rubens * Galileo Galilei * moon Subject RIV: AL - Art, Architecture, Cultural Heritage

PETER loop. Multifunctional test facility for thermal hydraulic investigations of PWR fuel elements

International Nuclear Information System (INIS)

Ganzmann, I.; Hille, D.; Staude, U.

2009-01-01

The reliable fuel element behavior during the complete fuel cycle is one of the fundamental prerequisites of a safe and efficient nuclear power plant operation. The fuel element behavior with respect to pressure drop and vibration impact cannot be simulated by means of fluid-structure interaction codes. Therefore it is necessary to perform tests using fuel element mock-ups (1:1). AREVA NP has constructed the test facility PETER (PWR fuel element tests in Erlangen) loop. The modular construction allows maximum flexibility for any type of fuel elements. Modern measuring instrumentation for flow, pressure and vibration characterization allows the analysis of cause and consequences of thermal hydraulic phenomena. PETER loop is the standard test facility for the qualification of dynamic fuel element behavior in flowing fluid and is used for failure mode analysis.

Co-electrodeposition of hard Ni-W/diamond nanocomposite coatings

Science.gov (United States)

Zhang, Xinyu; Qin, Jiaqian; Das, Malay Kumar; Hao, Ruru; Zhong, Hua; Thueploy, Adisak; Limpanart, Sarintorn; Boonyongmaneerat, Yuttanant; Ma, Mingzhen; Liu, Riping

2016-02-01

Electroplated hard chrome coating is widely used as a wear resistant coating to prolong the life of mechanical components. However, the electroplating process generates hexavalent chromium ion which is known carcinogen. Hence, there is a major effort throughout the electroplating industry to replace hard chrome coating. Composite coating has been identified as suitable materials for replacement of hard chrome coating, while deposition coating prepared using traditional co-deposition techniques have relatively low particles content, but the content of particles incorporated into a coating may fundamentally affect its properties. In the present work, Ni-W/diamond composite coatings were prepared by sediment co-electrodeposition from Ni-W plating bath, containing suspended diamond particles. This study indicates that higher diamond contents could be successfully co-deposited and uniformly distributed in the Ni-W alloy matrix. The maximum hardness of Ni-W/diamond composite coatings is found to be 2249 ± 23 Hv due to the highest diamond content of 64 wt.%. The hardness could be further enhanced up to 2647 ± 25 Hv with heat treatment at 873 K for 1 h in Ar gas, which is comparable to hard chrome coatings. Moreover, the addition of diamond particles could significantly enhance the wear resistance of the coatings.

Finite element design for the HPHT synthesis of diamond

Science.gov (United States)

Li, Rui; Ding, Mingming; Shi, Tongfei

2018-06-01

The finite element method is used to simulate the steady-state temperature field in diamond synthesis cell. The 2D and 3D models of the China-type cubic press with large deformation of the synthesis cell was established successfully, which has been verified by situ measurements of synthesis cell. The assembly design, component design and process design for the HPHT synthesis of diamond based on the finite element simulation were presented one by one. The temperature field in a high-pressure synthetic cavity for diamond production is optimized by adjusting the cavity assembly. A series of analysis about the influence of the pressure media parameters on the temperature field are examined through adjusting the model parameters. Furthermore, the formation mechanism of wasteland was studied in detail. It indicates that the wasteland is inevitably exists in the synthesis sample, the distribution of growth region of the diamond with hex-octahedral is move to the center of the synthesis sample from near the heater as the power increasing, and the growth conditions of high quality diamond is locating at the center of the synthesis sample. These works can offer suggestion and advice to the development and optimization of a diamond production process.

Growing of synthetic diamond boron-doped films for analytical applications

International Nuclear Information System (INIS)

Barros, Rita de Cassia Mendes de; Suarez-Iha, Maria Encarnacion Vazquez; Corat, Evaldo Jose; Iha, Koshun

1999-01-01

Chemical vapor deposition (CVD) technology affords the possibility of producing synthetic diamond film electrodes, with several advantageous properties due the unique characteristics of diamond. In this work, we present the study of boron-doped diamond films growth on molybdenum and silicon substrates, using boron trioxide as dopant in a filament assisted CVD reactor. The objective was to obtain semiconductor diamond for use as electrode. The samples were characterized by scanning electron microscopy and Raman spectroscopy to confirm morphology and doping levels. We have assembled electrodes with the various samples, Pt, Mo, Si and diamond, by utilizing brass and left as base materials. The electrodes were tested in neutralization potentiometric titrations for future use in electroanalysis. Boron-doped electrodes have very good performance compared with Pt, widely used in analytical chemistry. (author)

Measurement of barrier height of Pd on diamond (100) surface by X-ray photoelectron spectroscopy

Energy Technology Data Exchange (ETDEWEB)

Li, F.N. [Institute of Wide Band Gap Semiconductors, Xi' an Jiaotong University, Xi' an 710049 (China); Nation Key Laboratory of ASIC, HSRI, Shijiazhuang 050051 (China); Liu, J.W. [International Center for Young Scientists, National Institute for Materials Science (NIMS), 1-1 Namiki, Tsukuba, Ibaraki 3050044 (Japan); Zhang, J.W.; Wang, X.L.; Wang, W.; Liu, Z.C. [Institute of Wide Band Gap Semiconductors, Xi' an Jiaotong University, Xi' an 710049 (China); Wang, H.X., E-mail: hxwangcn@mail.xjtu.edu.cn [Institute of Wide Band Gap Semiconductors, Xi' an Jiaotong University, Xi' an 710049 (China)

2016-05-01

Highlights: • Metal-semiconductor contacts of Pd/hydrogen-terminated diamond and Pd/oxygen-terminated diamond have been investigated by XPS measurements. • The barrier height for Pd/hydrogen-terminated diamond (ohmic contact) has been measured to be −0.27 eV. • The barrier height for Pd/oxygen-terminated diamond (Schottky contact) has been measured to be 1.73 eV. - Abstract: Barrier height (Φ{sub BH}) values for Pd/hydrogen-terminated diamond (H-diamond) and Pd/oxygen-terminated diamond (O-diamond) have been investigated by X-ray photoelectron spectroscopy technique. H-diamond and O-diamond have been formed on the same diamond (100) layer grown by microwave plasma-enhanced chemical vapor deposition,on which Pd layers have been evaporated. The Φ{sub BH} values for Pd/H-diamond and Pd/O-diamond are determined to be −0.27 eV and 1.73 eV, respectively. It indicates that Pd is a suitable metal for ohmic and Schottky contacts on H-diamond and O-diamond, respectively. The experimental Φ{sub BH} values are in good agreement with the theoretical calculation results.

A tribute to Peter H Seeburg (1944-2016: a founding father of molecular neurobiology

Directory of Open Access Journals (Sweden)

William Wisden

2016-11-01

Full Text Available On 22nd August 2016, the fields of molecular neurobiology and endocrinology lost one of their pioneers and true giants, Peter Seeburg, who died aged 72, a day after his birthday. His funeral ceremony took place in Heidelberg where he had worked since 1988, first as a professor at the University of Heidelberg (ZMBH and then since 1996 as a director of the Max Plank Institute (Dept. of Molecular Neurobiology. Many of Peter’s former colleagues, students and postdocs came together with his family members to celebrate his life. Touching eulogies were given by no less than two Nobel prize winners: the physiologist Bert Sakmann, who collaborated with Peter for many years, and the developmental biologist Christiane Nüsslein-Vollhard, who was a friend and fellow PhD student with Peter. His professional contemporary, Heinrich Betz, gave a warm and endearing assessment of Peter’s contributions to the field of molecular neurobiology. One of Peter’s sons, Daniel P. Seeburg, now a neuroradiologist in the USA, and biotechnologist Karoly Nikolics, one of Peter’s friends from the days of Genentech, both emotionally summed up the warm and intense character of the man that many of his former students and postdocs knew.

Alluvial diamond resource potential and production capacity assessment of the Central African Republic

Science.gov (United States)

Chirico, Peter G.; Barthelemy, Francis; Ngbokoto, Francois A.

2010-01-01

In May of 2000, a meeting was convened in Kimberley, South Africa, and attended by representatives of the diamond industry and leaders of African governments to develop a certification process intended to assure that rough, exported diamonds were free of conflict concerns. This meeting was supported later in 2000 by the United Nations in a resolution adopted by the General Assembly. By 2002, the Kimberly Process Certification Scheme (KPCS) was ratified and signed by diamond-producing and diamond-importing countries. Over 70 countries were included as members of the KPCS at the end of 2007. To prevent trade in "conflict diamonds" while protecting legitimate trade, the KPCS requires that each country set up an internal system of controls to prevent conflict diamonds from entering any imported or exported shipments of rough diamonds. Every diamond or diamond shipment must be accompanied by a Kimberley Process (KP) certificate and be contained in tamper-proof packaging. The objective of this study was (1) to assess the naturally occurring endowment of diamonds in the Central African Republic (potential resources) based on geological evidence, previous studies, and recent field data and (2) to assess the diamond-production capacity and measure the intensity of mining activity. Several possible methods can be used to estimate the potential diamond resource. However, because there is generally a lack of sufficient and consistent data recording all diamond mining in the Central African Republic and because time to conduct fieldwork and accessibility to the diamond mining areas are limited, two different methodologies were used: the volume and grade approach and the content per kilometer approach. Estimates are that approximately 39,000,000 carats of alluvial diamonds remain in the eastern and western zones of the CAR combined. This amount is roughly twice the total amount of diamonds reportedly exported from the Central African Republic since 1931. Production capacity is

Status of diamond particle detectors

Energy Technology Data Exchange (ETDEWEB)

Krammer, M.; Adam, W.; Friedl, M.; Hrubec, J.; Pernegger, H.; Pernicka, M. [Institut fuer Hochenergiephysik der Oesterr. Akademie d. Wissenschaften, Nikolsdorferg. 18, A-1050 Vienna (Austria); Bauer, C. [MPI fuer Kernphysik, D-69029 Heidelberg (Germany); Berdermann, E.; Stelzer, H. [GSI, Darmstadt (Germany); Bogani, F. [LENS, Florence (Italy); Borchi, E.; Bruzzi, M.; Sciortino, S. [University of Florence, Florence (Italy); Colledani, C.; Dulinski, W.; Husson, D.; LeNormand, F.; Riester, G.L.; Turchetta, R. [LEPSI, CRN Strasbourg (France); Conway, J.; Fish, D.; Schnetzer, S.; Stone, R.; Tesarek, R.; Thomson, G.B.; Walsh, A.M. [Rutgers University, Piscataway, NJ (United States); Dabrowski, W.; Kaplon, J.; Meier, D.; Roe, S.; Rudge, A.; Wedenig, R.; Weilhammer, P. [CERN, CH-1211 Geneva (Switzerland); Delpierre, P.; Hallewell, G. [CPPM, Marseille (France); Deneuville, A.; Cheeraert, E. [LEPES, Grenoble (France); Eijk, B.V.; Hartjes, F. [NIKHEF, Amsterdam (Netherlands); Fallou, A. [CPPM, Marseille (France); Foulon, F. [Centre d' Etudes de Saclay, 91191 Gif-Sur-Yvette (France); Gan, K.K.; Kagan, H.; Kass, R.; Trawick, M.; Zoeller, M. [The Ohio State University, Columbus, OH (United States); Grigoriev, E.; Knoepfle, K.T. [MPI fuer Kernphysik, D-69029 Heidelberg (Germany); Hall-Wilton, R. [Bristol University, Bristol (United Kingdom); Han, S.; Ziock, H. [Los Alamos National Laboratory, Research Division, Los Alamos, NM (United States); Kania, D. [Lawrence Livermore National Laboratory, Livermore, CA (United States); Manfredi, P.F.; Re, V.; Speziali, V. [Universita di Pavia, Dipartimento di Elettronica, 27100 Pavia (Italy); Mishina, M. [FNAL, Batavia, IL (United States); Pan, L.S. [Sandia National Laboratory, Albuquerque, NM (United States); Roff, D.; Tapper, R.J. [Bristol University, Bristol (United Kingdom); Trischuk, W. [University of Toronto, Toronto (Canada)

1998-11-21

To continue the exciting research in the field of particle physics new accelerators and experiments are under construction. In some of these experiments, e.g. ATLAS and CMS at the Large Hadron Collider at CERN or HERA-B at DESY, the detectors have to withstand an extreme environment. The detectors must be radiation hard, provide a very fast signal, and be as thin as possible. The properties of CVD diamond allow to fulfill these requirements and make it an ideal material for the detectors close to the interaction region of these experiments, i.e. the vertex detectors or the inner trackers. The RD42 collaboration is developing diamond detectors for these applications. The program of RD42 includes the improvement of the charge collection properties of CVD diamond, the study of the radiation hardness and the development of low-noise radiation hard readout electronics. An overview of the progress achieved during the last years will be given. (Copyright (c) 1998 Elsevier Science B.V., Amsterdam. All rights reserved.)

Status of diamond particle detectors

International Nuclear Information System (INIS)

Krammer, M.; Adam, W.; Friedl, M.; Hrubec, J.; Pernegger, H.; Pernicka, M.; Bauer, C.; Berdermann, E.; Stelzer, H.; Bogani, F.; Borchi, E.; Bruzzi, M.; Sciortino, S.; Colledani, C.; Dulinski, W.; Husson, D.; LeNormand, F.; Riester, G.L.; Turchetta, R.; Conway, J.; Fish, D.; Schnetzer, S.; Stone, R.; Tesarek, R.; Thomson, G.B.; Walsh, A.M.; Dabrowski, W.; Kaplon, J.; Meier, D.; Roe, S.; Rudge, A.; Wedenig, R.; Weilhammer, P.; Delpierre, P.; Hallewell, G.; Deneuville, A.; Cheeraert, E.; Eijk, B.V.; Hartjes, F.; Fallou, A.; Foulon, F.; Gan, K.K.; Kagan, H.; Kass, R.; Trawick, M.; Zoeller, M.; Grigoriev, E.; Knoepfle, K.T.; Hall-Wilton, R.; Han, S.; Ziock, H.; Kania, D.; Manfredi, P.F.; Re, V.; Speziali, V.; Mishina, M.; Pan, L.S.; Roff, D.; Tapper, R.J.; Trischuk, W.

1998-01-01

To continue the exciting research in the field of particle physics new accelerators and experiments are under construction. In some of these experiments, e.g. ATLAS and CMS at the Large Hadron Collider at CERN or HERA-B at DESY, the detectors have to withstand an extreme environment. The detectors must be radiation hard, provide a very fast signal, and be as thin as possible. The properties of CVD diamond allow to fulfill these requirements and make it an ideal material for the detectors close to the interaction region of these experiments, i.e. the vertex detectors or the inner trackers. The RD42 collaboration is developing diamond detectors for these applications. The program of RD42 includes the improvement of the charge collection properties of CVD diamond, the study of the radiation hardness and the development of low-noise radiation hard readout electronics. An overview of the progress achieved during the last years will be given. (Copyright (c) 1998 Elsevier Science B.V., Amsterdam. All rights reserved.)

Repulsive effects of hydrophobic diamond thin films on biomolecule detection

Energy Technology Data Exchange (ETDEWEB)

Ruslinda, A. Rahim, E-mail: ruslindarahim@gmail.com [Institute of Nano Electronic Engineering, Universiti Malaysia Perlis, Jln Kgr-Alor Setar, Seriab, 01000 Kangar, Perlis (Malaysia); Department of Nano Science and Nano Engineering, School of Advance Science and Engineering, Ohkubo 3-4-1, Shinjuku, 169-8555 Tokyo (Japan); Ishiyama, Y. [Department of Nano Science and Nano Engineering, School of Advance Science and Engineering, Ohkubo 3-4-1, Shinjuku, 169-8555 Tokyo (Japan); Penmatsa, V. [Department of Mechanical and Materials Engineering, Florida International University, 10555 West Flagler Street, Miami, FL 33174 (United States); Ibori, S.; Kawarada, H. [Department of Nano Science and Nano Engineering, School of Advance Science and Engineering, Ohkubo 3-4-1, Shinjuku, 169-8555 Tokyo (Japan)

2015-02-15

Highlights: • We report the effect of fluorine plasma treatment on diamond thin film to resist the nonspecific adsorption of biomolecules. • The diamond thin film were highly hydrophobic with a surface energy value of ∼25 mN/m. • The repulsive effect shows excellent binding efficiency for both DNA and HIV-1 Tat protein. - Abstract: The repulsive effect of hydrophobic diamond thin film on biomolecule detection, such as single-nucleotide polymorphisms and human immunodeficiency virus type 1 trans-activator of transcription peptide protein detection, was investigated using a mixture of a fluorine-, amine-, and hydrogen-terminated diamond surfaces. These chemical modifications lead to the formation of a surface that effectively resists the nonspecific adsorption of proteins and other biomolecules. The effect of fluorine plasma treatment on elemental composition was also investigated via X-ray photoelectron spectroscopy (XPS). XPS results revealed a fluorocarbon layer on the diamond thin films. The contact angle measurement results indicated that the fluorine-treated diamond thin films were highly hydrophobic with a surface energy value of ∼25 mN/m.

Repulsive effects of hydrophobic diamond thin films on biomolecule detection

International Nuclear Information System (INIS)

Ruslinda, A. Rahim; Ishiyama, Y.; Penmatsa, V.; Ibori, S.; Kawarada, H.

2015-01-01

Highlights: • We report the effect of fluorine plasma treatment on diamond thin film to resist the nonspecific adsorption of biomolecules. • The diamond thin film were highly hydrophobic with a surface energy value of ∼25 mN/m. • The repulsive effect shows excellent binding efficiency for both DNA and HIV-1 Tat protein. - Abstract: The repulsive effect of hydrophobic diamond thin film on biomolecule detection, such as single-nucleotide polymorphisms and human immunodeficiency virus type 1 trans-activator of transcription peptide protein detection, was investigated using a mixture of a fluorine-, amine-, and hydrogen-terminated diamond surfaces. These chemical modifications lead to the formation of a surface that effectively resists the nonspecific adsorption of proteins and other biomolecules. The effect of fluorine plasma treatment on elemental composition was also investigated via X-ray photoelectron spectroscopy (XPS). XPS results revealed a fluorocarbon layer on the diamond thin films. The contact angle measurement results indicated that the fluorine-treated diamond thin films were highly hydrophobic with a surface energy value of ∼25 mN/m

Conflict diamonds — unfinished business | IDRC - International ...

International Development Research Centre (IDRC) Digital Library (Canada)

2011-07-22

Jul 22, 2011 ... ... diamonds reached this year will not be effective if it is not monitored, and if the countries ... What we do know is that 75 percent of the world's gem diamonds are mined in ... It makes the Kimberley accord weaker than any other international ... a British NGO, have been nominated for the Nobel Peace Prize.

Laser Raman microprobe spectroscopy as a diagnostic for the characterisation of diamond and diamond like carbon (DLC) thin films

International Nuclear Information System (INIS)

Johnston, C.

1990-10-01

Invariably when manufacturing an artificial diamond film a mixture of carbon is deposited - tetragonally bonded (diamond), trigonally bonded (graphite) and other allotropic crystalline forms and amorphous carbons. This imposes a need for careful analysis to determine exactly what carbon types constitute the films. Raman spectroscopy is particularly sensitive to crystal and atomic structure and has a number of advantages which make it one of the most useful techniques for interrogating diamond and DLC thin films. Although Raman spectroscopy alone cannot fully characterise the film, it can give more information than simply what particular form of carbon or other impurities are present in the film. It can be used to determine the ratio of sp 2 to sp 3 bonding within the film, and to some extent the crystallite or domain size and the internal stress of the film. The use of laser Raman microprobe spectroscopy as a diagnostic tool in the analysis of diamond and DLC thin films is demonstrated for a variety of carbon films on various substrates and the characterisation of these films is discussed. (author)

Diamonds from Myanmar and Thailand: Characteristics and possible origins

International Nuclear Information System (INIS)

Griffin, W.L.; Commonwealth Scientific and Industrial Research Organisation, North Ryde, NSW; Win, T.T.; Andrew, A.S.; Davies, R.; Wathanakul, P.; Metcalfe, I.

2000-01-01

Alluvial diamonds with no obvious sources ('headless placers') are found in several areas of SE Asia and Oceania, including Myanmar, southern Thailand (Phuket), Sumatra, Kalimantan and eastern Australia. These deposits occur in relatively young geological terrains, in contrast to the Archaean or Proterozoic terrains that host most primary diamond deposits and their associated alluvial workings. Significant quantities of diamonds have been recovered from two areas in Myanmar, Momeik in the northern part of the country, and Theindaw in the southern part, and from the Phuket-Takuapa area of SW Thailand. Smaller quantities have been found in several other localities, notably in the Taungoo-Htantabin area of Myanmar. The Momeik diamonds are recovered during mining of gemstone gravels; the Theindaw and Phuket diamonds are by-products of tin dredging. To understand the origin of these enigmatic diamonds and to provide an improved exploration model, we are carrying out detailed studies of the morphology, mineral inclusions, internal growth structures and growth history, nitrogen concentration and aggregation state, and carbon isotopic composition of diamonds from Myanmar, Thailand and eastern Australia. We have examined >40 stones from Phuket, >110 from Theindaw and >25 from Momeik; these range in size from <0.1 ct to 3.5 ct, averaging ca 0.2 ct. While there are differences among the samples from different areas, the small sample size means these may not be representative and the similarities among the samples are striking. They are therefore described together here. More detailed data are given by Win et al., (1998) and Wathanakul et al., (1998)

Microwave plasma deposition of diamond like carbon coatings

Indian Academy of Sciences (India)

Abstract. The promising applications of the microwave plasmas have been appearing in the fields of chemical processes and semiconductor manufacturing. Applications include surface deposition of all types including diamond/diamond like carbon (DLC) coatings, etching of semiconductors, promotion of organic reactions, ...

Arabic plant names and botany in Arabic civilisation. The contribution of Peter Forsskål (1732-1763) and others

DEFF Research Database (Denmark)

Provencal, Philippe

2012-01-01

A presentation of the state of Botany in the Classical Arabic Civilisation and of some of the main contributors to our knowledge in this field, especially Peter Forsskål.......A presentation of the state of Botany in the Classical Arabic Civilisation and of some of the main contributors to our knowledge in this field, especially Peter Forsskål....

Measurements and Studies of Secondary Electron Emission of Diamond Amplified Photocathode

Energy Technology Data Exchange (ETDEWEB)

Wu,Q.

2008-10-01

The Diamond Amplified Photocathode (DAP) is a novel approach to generating electrons. By following the primary electron beam, which is generated by traditional electron sources, with an amplifier, the electron beam available to the eventual application is increased by 1 to 2 orders of magnitude in current. Diamond has a very wide band gap of 5.47eV which allows for a good negative electron affinity with simple hydrogenation, diamond can hold more than 2000MV/m field before breakdown. Diamond also provides the best rigidity among all materials. These two characters offer the capability of applying high voltage across very thin diamond film to achieve high SEY and desired emission phase. The diamond amplifier also is capable of handling a large heat load by conduction and sub-nanosecond pulse input. The preparation of the diamond amplifier includes thinning and polishing, cleaning with acid etching, metallization, and hydrogenation. The best mechanical polishing available can provide high purity single crystal diamond films with no less than 100 {micro}m thickness and <15 nm Ra surface roughness. The ideal thickness for 700MHz beam is {approx}30 {micro}m, which requires further thinning with RIE or laser ablation. RIE can achieve atomic layer removal precision and roughness eventually, but the time consumption for this procedure is very significant. Laser ablation proved that with <266nm ps laser beam, the ablation process on the diamond can easily achieve removing a few microns per hour from the surface and <100nm roughness. For amplifier application, laser ablation is an adequate and efficient process to make ultra thin diamond wafers following mechanical polishing. Hydrogenation will terminate the diamond surface with monolayer of hydrogen, and form NEA so that secondary electrons in the conduction band can escape into the vacuum. The method is using hydrogen cracker to strike hydrogen atoms onto the bare diamond surface to form H-C bonds. Two independent

Polycrystalline CVD diamond device level modeling for particle detection applications