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Sample records for program diamond lake

  1. Perchlorate in Lake Water from an Operating Diamond Mine.

    Science.gov (United States)

    Smith, Lianna J D; Ptacek, Carol J; Blowes, David W; Groza, Laura G; Moncur, Michael C

    2015-07-07

    Mining-related perchlorate [ClO4(-)] in the receiving environment was investigated at the operating open-pit and underground Diavik diamond mine, Northwest Territories, Canada. Samples were collected over four years and ClO4(-) was measured in various mine waters, the 560 km(2) ultraoligotrophic receiving lake, background lake water and snow distal from the mine. Groundwaters from the underground mine had variable ClO4(-) concentrations, up to 157 μg L(-1), and were typically an order of magnitude higher than concentrations in combined mine waters prior to treatment and discharge to the lake. Snow core samples had a mean ClO4(-) concentration of 0.021 μg L(-1) (n=16). Snow and lake water Cl(-)/ClO4(-) ratios suggest evapoconcentration was not an important process affecting lake ClO4(-) concentrations. The multiyear mean ClO4(-) concentrations in the lake were 0.30 μg L(-1) (n = 114) in open water and 0.24 μg L(-1) (n = 107) under ice, much below the Canadian drinking water guideline of 6 μg L(-1). Receiving lake concentrations of ClO4(-) generally decreased year over year and ClO4(-) was not likely [biogeo]chemically attenuated within the receiving lake. The discharge of treated mine water was shown to contribute mining-related ClO4(-) to the lake and the low concentrations after 12 years of mining were attributed to the large volume of the receiving lake.

  2. Temperature fluctuations underneath the ice in Diamond Lake, Hennepin County, Minnesota

    Science.gov (United States)

    Kletetschka, Gunther; Fischer, Tomas; Mls, Jiří; DěDeček, Petr

    2013-06-01

    Diamond Lake in Minnesota is covered every winter with ice and snow providing a modified thermal insulation between water and air. Autonomous temperature sensors, data loggers, were placed in this lake so that hourly measurements could be obtained from the snow-covered ice and water. The sensors that became frozen measured damped and delayed thermal response from the air-temperature fluctuation. Those sensors that were deeper within the snow-covered ice measured continuous, almost constant, temperature values near freezing. Several of them were within the liquid water and responded with a fluctuation of 24 h periods of amplitudes up to 0.2°C. Our analysis of the vertical temperature profiles suggested that the source of periodic water heating comes from the lake bottom. Because of the absence of daily temperature variations of the snow-covered ice, the influence of the air-temperature fluctuation can be ruled out. We attribute the heating process to the periodic inflow of groundwater to the lake and the cooling to the heat diffusion to the overlying ice cover. The periodic groundwater inflow is interpreted due to solid Earth tides, which cause periodic fluctuations of the groundwater pressure head.

  3. 75 FR 34049 - FM Table of Allotments (The Dalles, Tualatin, Eugene, Albany, Lebanon, Paisley, and Diamond Lake...

    Science.gov (United States)

    2010-06-16

    ... Diamond Lake, Oregon and Goldendale, WA) AGENCY: Federal Communications Commission ACTION: Final rule... 1.420(j) of the Commission's Rules, we are granting the Joint Parties' Motion to Dismiss. In doing... payments that are less than their respective legitimate and prudent expenses incurred in connection with...

  4. Red Lake Forestry Greenhouse Program

    Science.gov (United States)

    Gloria Whitefeather-Spears

    2002-01-01

    In 1916, The Red Lake Indian Forest Act was created. The Red Lake Band of Chippewa in Minnesota stood alone and refused to consent to allotment. Consequently, The Red Lake Band is the only tribe in Minnesota for which a congressional act was passed to secure a permanent economic foundation for the band and its future.

  5. Under-ice noise generated from diamond exploration in a Canadian sub-arctic lake and potential impacts on fishes.

    Science.gov (United States)

    Mann, D; Cott, P; Horne, B

    2009-11-01

    Mineral exploration is increasing in Canada, particularly in the north where extensive diamond mining and exploration are occurring. This study measured the under-ice noise produced by a variety of anthropogenic sources (drilling rigs, helicopters, aircraft landing and takeoff, ice-road traffic, augers, snowmobiles, and chisels) at a winter-based diamond exploration project on Kennady Lake in the Northwest Territories, Canada to infer the potential impact of noise on fishes in the lake. The root-mean-square noise level measured 5 m from a small diameter drill was approximately 46 dB greater (22 kHz bandwidth) than ambient noise, while the acoustic particle velocity was approximately 40 dB higher than ambient levels. The loudest sounds at the exploration site were produced by ice cracking, both natural and during landing and takeoff of a C130 Hercules aircraft. However, even walking on the snow above the ice raised ambient sound levels by approximately 30 dB. Most of the anthropogenic sounds are likely detectable by fishes with hearing specializations, such as chubs and suckers. Other species without specialized hearing adaptations will detect these sounds only close to the source. The greatest potential impact of noise from diamond exploration is likely to be the masking of sounds for fishes with sensitive hearing.

  6. Genetic evaluation of a Great Lakes lake trout hatchery program

    Science.gov (United States)

    Page, K.S.; Scribner, K.T.; Bast, D.; Holey, M.E.; Burnham-Curtis, M. K.

    2005-01-01

    Efforts over several decades to restore lake trout Salvelinus namaycush in U.S. waters of the upper Great Lakes have emphasized the stocking of juveniles from each of six hatchery broodstocks. Retention of genetic diversity across all offspring life history stages throughout the hatchery system has been an important component of the restoration hatchery and stocking program. Different stages of the lake trout hatchery program were examined to determine how effective hatchery practices have been in minimizing the loss of genetic diversity in broodstock adults and in progeny stocked. Microsatellite loci were used to estimate allele frequencies, measures of genetic diversity, and relatedness for wild source populations, hatchery broodstocks, and juveniles. We also estimated the effective number of breeders for each broodstock. Hatchery records were used to track destinations of fertilized eggs from all spawning dates to determine whether adult contributions to stocking programs were proportional to reproductive effort. Overall, management goals of maintaining genetic diversity were met across all stages of the hatchery program; however, we identified key areas where changes in mating regimes and in the distribution of fertilized gametes and juveniles could be improved. Estimates of effective breeding population size (Nb) were 9-41% of the total number of adults spawned. Low estimates of Nb were primarily attributed to spawning practices, including the pooling of gametes from multiple males and females and the reuse of males. Nonrandom selection and distribution of fertilized eggs before stocking accentuated declines in effective breeding population size and increased levels of relatedness of juveniles distributed to different rearing facilities and stocking locales. Adoption of guidelines that decrease adult reproductive variance and promote more equitable reproductive contributions of broodstock adults to juveniles would further enhance management goals of

  7. 75 FR 6354 - NOAA Great Lakes Habitat Restoration Program Project Grants under the Great Lakes Restoration...

    Science.gov (United States)

    2010-02-09

    ... National Oceanic and Atmospheric Administration RIN 0648-ZC10 NOAA Great Lakes Habitat Restoration Program Project Grants under the Great Lakes Restoration Initiative; Correction AGENCY: National Marine Fisheries... notice published in the Federal Register on January 19, 2010. That notice announced the NOAA Great Lakes...

  8. Evaluating an HIV and AIDS Community Training Partnership Program in Five Diamond Mining Communities in South Africa

    Science.gov (United States)

    Rispel, L. C.; Peltzer, K.; Nkomo, N.; Molomo, B.

    2010-01-01

    In 2006, De Beers Consolidated Diamond Mines in South Africa entered into a partnership, with the Soul City Institute for Health and Development Communications to implement an HIV and AIDS Community Training Partnership Program (CTPP), initially in five diamond mining areas in three provinces of South Africa. The aim of CTPP was to improve HIV…

  9. L-Lake zooplankton: L-Lake/Steel Creek Biological Monitoring Program, November 1985--December 1991

    Energy Technology Data Exchange (ETDEWEB)

    Bowers, J.A. [Westinghouse Savannah River Co., Aiken, SC (United States); Bowen, M. [Normandeau Associates, Inc., New Ellenton, SC (United States)

    1992-03-01

    The L- Lake Biological Monitoring Program was designed to meet environmental regulatory requirements associated with the restart of L-Reactor and address portions of Section 316(a) of the Clean Water Act, which requires an applicant for a discharge permit to provide scientific evidence that the discharge causes no significant impact on the indigenous ecosystem. The Department of Energy (DOE) must demonstrate that the discharge of L-Reactor affluent into L Lake will not inhibit the eventual establishment of a ``Balanced Biological Community`` (BBC) in at least 50% of the lake. This report details results of monitoring zooplankton populations in L-Lake.

  10. L-Lake fish: L-Lake/Steel Creek Biological Monitoring Program, January 1986--December 1991

    Energy Technology Data Exchange (ETDEWEB)

    Sayers, R.E. Jr.; Mealing, H.G. III [Normandeau Associates, Inc., New Ellenton, SC (United States)

    1992-04-01

    The L Lake Biological Monitoring Program was designed to meet environmental regulatory requirements associated with the re-start of L-Reactor and address portions of Section 316(a) of the Clean Water Act, which requires an applicant for a discharge permit to provide scientific evidence that the discharge causes no significant impact on the indigenous ecosystem. The Department of Energy (DOE) must demonstrate that the discharge of L-Reactor effluent into L Lake will not inhibit the eventual establishment of a ``Balanced Biological Community`` (BBC) in at least 50% of the lake.

  11. Lake and lake-related drainage area parameters for site investigation program

    Energy Technology Data Exchange (ETDEWEB)

    Blomqvist, P.; Brunberg, A.K. [Uppsala Univ. (Sweden). Dept. of Limnology; Brydsten, L [Umeaa Univ. (Sweden). Dept. of Ecology and Environmental Science

    2000-09-01

    In this paper, a number of parameters of importance to a preliminary determination of the ecological function of lakes are presented. The choice of parameters have been made with respect to a model for the determination of the nature conservation values of lakes which is currently being developed by the authors of this report, but is also well suited for a general description of the lake type and the functioning of the inherent ecosystem. The parameters have been divided into five groups: (1) The location of the object relative important gradients in the surrounding nature; (2) The lake catchment area and its major constituents; (3) The lake morphometry; (4) The lake ecosystem; (5) Human-induced damages to the lake ecosystem. The first two groups, principally based on the climate, hydrology, geology and vegetation of the catchment area represent parameters that can be used to establish the rarity and representativity of the lake, and will in the context of site investigation program be used as a basis for generalisation of the results. The third group, the lake morphometry parameters, are standard parameters for the outline of sampling programmes and for calculations of the physical extension of different key habitats in the system. The fourth group, the ecosystem of the lake, includes physical, chemical and biological parameters required for determination of the stratification pattern, light climate, influence from the terrestrial ecosystem of the catchment area, trophic status, distribution of key habitats, and presence of fish and rare fauna and flora in the lake. In the context of site investigation program, the parameters in these two groups will be used for budget calculations of the flow of energy and material in the system. The fifth group, finally, describes the degree on anthropogenic influence on the ecosystem and will in the context of site investigation programmes be used to judge eventual malfunctioning within the entire, or parts of, the lake

  12. The limnology of L Lake: Results of the L-Lake monitoring program, 1986--1989

    Energy Technology Data Exchange (ETDEWEB)

    Bowers, J.A.

    1991-12-15

    L Lake was constructed in 1985 on the upper regions of Steel Creek, SRS to mitigate the heated effluents from L Reactor. In addition to the NPDES permit specifications (Outfall L-007) for the L-Reactor outfall, DOE-SR executed an agreement with the South Carolina Department of Health and Environmental Control (SCDHEC), that thermal effluents from L-Reactor will not substantially alter ecosystem components in the approximate lower half of L Lake. This region should be inhabited by Balanced (Indigenous) Biological Communities (BBCs) in accordance with Section 316(a) of the Pollution Control (Clean Water) Act (Public Law 92-500). In response to this requirement the Environmental Sciences Section/Ecology Group initiated a comprehensive biomonitoring program which documented the development of BBCs in L Lake from January 1986 through December 1989. This report summarizes the principal results of the program with regards to BBC compliance issues and community succession in L Lake. The results are divided into six sections: water quality, macronutrients, and phytoplankton, aquatic macrophytes, zooplankton, benthic macroinvertebrates, fish, and community succession. One of the prime goals of the program was to detect potential reactor impacts on L Lake.

  13. 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.

  14. Water quality and algal conditions in the North Umpqua River, Oregon, 1995-2007, and their response to Diamond Lake restoration

    Science.gov (United States)

    Carpenter, Kurt D.; Anderson, Chauncey W.; Jones, Mikeal E.

    2014-01-01

    The Wild and Scenic North Umpqua River is one of the highest-quality waters in the State of Oregon, supporting runs of wild salmon, steelhead, and trout. For many years, blooms of potentially toxic blue-green algae in Diamond and Lemolo Lakes have threatened water quality, fisheries, and public health. The blooms consist primarily of Anabaena, a nitrogen (N)-fixing planktonic alga that appears to have contributed to N enrichment, which could account for changes in communities and biomass of periphyton, or attached benthic algae, in the river. Periphyton can become a nuisance in summer by affecting riffle habitat and causing high pH that fails to meet State of Oregon water-quality standards. These symptoms of nutrient enrichment in the North Umpqua River were first documented in 1995, and the symptoms have continued since then. Restoring natural ecosystem processes that store nutrients rather than fueling algae might help improve pH and water-clarity conditions.

  15. Lake Roosevelt Fisheries Monitoring Program; 1988-1989 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Peone, Tim L.; Scholz, Allan T.; Griffith, James R.

    1990-10-01

    In the Northwest Power Planning Council's 1987 Columbia River Basin Fish and Wildlife Program (NPPC 1987), the Council directed the Bonneville Power Administration (BPA) to construct two kokanee salmon (Oncorhynchus nerka) hatcheries as partial mitigation for the loss of anadromous salmon and steelhead incurred by construction of Grand Coulee Dam [Section 903 (g)(l)(C)]. The hatcheries will produce kokanee salmon for outplanting into Lake Roosevelt as well as rainbow trout (Oncorhynchus mykiss) for the Lake Roosevelt net-pen program. In section 903 (g)(l)(E), the Council also directed BPA to fund a monitoring program to evaluate the effectiveness of the kokanee hatcheries. The monitoring program included the following components: (1) a year-round, reservoir-wide, creel survey to determine angler use, catch rates and composition, and growth and condition of fish; (2) assessment of kokanee, rainbow, and walleye (Stizostedion vitreum) feeding habits and densities of their preferred prey, and; (3) a mark and recapture study designed to assess the effectiveness of different locations where hatchery-raised kokanee and net pen reared rainbow trout are released. The above measures were adopted by the Council based on a management plan, developed by the Upper Columbia United Tribes Fisheries Center, Spokane Indian Tribe, Colville Confederated Tribes, Washington Department of Wildlife, and National Park Service, that examined the feasibility of restoring and enhancing Lake Roosevelt fisheries (Scholz et al. 1986). In July 1988, BPA entered into a contract with the Spokane Indian Tribe to initiate the monitoring program. The projected duration of the monitoring program is through 1995. This report contains the results of the monitoring program from August 1988 to December 1989.

  16. Lake Roosevelt Fisheries Monitoring Program; 1990 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Griffith, Janelle R.; Scholz, Allan T. (Eastern Washington University, Upper Columbia United Tribes Fisheries Research Center, Cheney, WA)

    1991-09-01

    As partial mitigation for the loss of anadromous salmon and steelhead incurred by construction of Grand Coulee Dam, the Northwest Power Planning Council directed Bonneville Power Administration (BPA) to construct two kokanee salmon (Oncorhynchus nerka) hatcheries on Lake Roosevelt (NPPC 1987 [Section 903 (g)(l)(C)]). The hatcheries are to produce 8 million kokanee salmon fry or 3.2 million adults for outplanting into Lake Roosevelt as well as 500,000 rainbow trout (Oncorhynchus mykiss) for the Lake Roosevelt net-pen programs. In section 903 (g)(l)(E), the Council also directed BPA to fund a monitoring program to evaluate the effectiveness of the kokanee hatcheries. The monitoring program included the following components: (1) conduction of a year-round creel census survey to determine angler pressure, catch rates and composition, growth and condition of fish caught by anglers, and economic value of the fishery. Comparisons will be made before and after hatcheries are on-line to determine hatchery effectiveness; (2) conduct an assessment of kokanee, rainbow trout, and walleye feeding habits, growth rates, and densities of their preferred prey at different locations in the reservoir and how reservoir operations affect population dynamics of preferred prey organisms. This information will be used to determine kokanee and rainbow trout stocking locations, stocking densities and stocking times; (3) conduct a mark-recapture study designed to assess effectiveness of various release times and locations for hatchery-raised kokanee and net-pen raised rainbow so fish-loss over Grand Coulee Dam will be minimized, homing to egg collection sites will be improved and angler harvest will be increased. The above measures were adopted by the Council based on a management plan developed by Upper Columbia United Tribes Fisheries Center, Spokane Indian Tribe, Colville Confederated Tribes, Washington Department of Wildlife, and the National Park Service. This plan examined the

  17. Diamond photonics

    Science.gov (United States)

    Aharonovich, Igor; Greentree, Andrew D.; Prawer, Steven

    2011-07-01

    Diamond, a material marvelled for its strength, beauty and perfection, was first used to polish stone axes in Neolithic times. This most ancient of materials is now being touted by many as the ideal platform for quantum-age technologies. In this Review, we describe how the properties of diamond match the requirements of the 'second quantum revolution'. We also discuss recent progress in the development of diamond -- and particularly diamond colour centres -- for transforming quantum information science into practical quantum information technology.

  18. Industrial diamond

    Science.gov (United States)

    Olson, D.W.

    2013-01-01

    Estimated 2012 world production of natural and synthetic industrial diamond was about 4.45 billion carats. During 2012, natural industrial diamonds were produced in at least 20 countries, and synthetic industrial diamond was produced in at least 12 countries. About 99 percent of the combined natural and synthetic global output was produced in Belarus, China, Ireland, Japan, Russia, South Africa and the United States. During 2012, China was the world’s leading producer of synthetic industrial diamond followed by the United States and Russia. In 2012, the two U.S. synthetic producers, one in Pennsylvania and the other in Ohio, had an estimated output of 103 million carats, valued at about $70.6 million. This was an estimated 43.7 million carats of synthetic diamond bort, grit, and dust and powder with a value of $14.5 million combined with an estimated 59.7 million carats of synthetic diamond stone with a value of $56.1 million. Also in 2012, nine U.S. firms manufactured polycrystalline diamond (PCD) from synthetic diamond grit and powder. The United States government does not collect or maintain data for either domestic PCD producers or domestic chemical vapor deposition (CVD) diamond producers for quantity or value of annual production. Current trade and consumption quantity data are not available for PCD or for CVD diamond. For these reasons, PCD and CVD diamond are not included in the industrial diamond quantitative data reported here.

  19. Evaluating an HIV and AIDS Community Training Partnership Program in five diamond mining communities in South Africa.

    Science.gov (United States)

    Rispel, L C; Peltzer, K; Nkomo, N; Molomo, B

    2010-11-01

    In 2006, De Beers Consolidated Diamond Mines in South Africa entered into a partnership with the Soul City Institute for Health and Development Communications to implement an HIV and AIDS Community Training Partnership Program (CTPP), initially in five diamond mining areas in three provinces of South Africa. The aim of CTPP was to improve HIV knowledge and to contribute to positive behavior changes in the targeted populations. This paper describes the evaluation of the CTPP, one year after implementation. The evaluation combined qualitative interviews with key informants and trainers and a post-intervention survey of 142 community members. The successes of the CTPP included capacity building of trainers through an innovative training approach and HIV and AIDS knowledge transfer to community trainers and targeted communities in remote mining towns. The Soul City edutainment brand is popular and emerged as a major reason for success. Challenges included insufficient attention paid to contextual factors, resource constraints and the lack of a monitoring and evaluation framework. Independent evaluations are useful to strengthen program implementation. In remote areas and resource constraint settings, partnerships between non-governmental organisations and corporations may be required for successful community HIV and AIDS initiatives. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

  20. Great Lakes maritime education program for K-12 teachers.

    Science.gov (United States)

    2011-02-01

    Michigan Technological University has led an educational/outreach effort for the Great Lake Maritime Research Institute since 2006. : Despite Michigan Techs relative isolation and long distance from most locations in the Great Lakes Basin, every s...

  1. Cooperative science to inform Lake Ontario management: Research from the 2013 Lake Ontario CSMI program

    Science.gov (United States)

    Watkins, James M.; Weidel, Brian C.; Fisk, Aaron T.; Rudstam, Lars G.

    2017-01-01

    Since the mid-1970s, successful Lake Ontario management actions including nutrient load and pollution reductions, habitat restoration, and fish stocking have improved Lake Ontario. However, several new obstacles to maintenance and restoration have emerged. This special issue presents management-relevant research from multiple agency surveys in 2011 and 2012 and the 2013 Cooperative Science and Monitoring Initiative (CSMI), that span diverse lake habitats, species, and trophic levels. This research focused on themes of nutrient loading and fate; vertical dynamics of primary and secondary production; fish abundance and behavior; and food web structure. Together these papers identify the status of many of the key drivers of the Lake Ontario ecosystem and contribute to addressing lake-scale questions and management information needs in Lake Ontario and the other Great Lakes and connecting water bodies.

  2. Educational Programs at the Lake Afton Public Observatory

    Science.gov (United States)

    Alexander, D. R.; Novacek, G. R.

    1994-05-01

    The Lake Afton Public Observatory was founded 14 years ago as a joint project of the city, county, local schools, and Wichita State University to provide educational programs for the public and school children. A staff of 4 professional astronomers presents daytime and evening programs at the Observatory and makes presentations in schools to over 20,000 people per year. Programs are scheduled 6 days a week during the academic year and 3 days a week in the summer. Our public programs deviate significantly from the traditional observatory open house by following a specific theme. Selection and discussion of each object is centered on that theme. For example, a program on The Life Story of a Star would view a diffuse nebula (to discuss star formation), a young star cluster (to discuss one outcome of star formation), a double star (to discuss how the properties of stars are determined), and a planetary nebula (to discuss the death of a star). To complement the observing experiences of our visitors, we have developed a wide range of interactive exhibits to develop the concepts touched on in the viewing programs. We have also developed exhibit lending kits for extended use in school classrooms, educational games, activity manuals for teachers, and short videos to introduce single concepts in the classroom. In the past year we have begun to offer a series of workshops for in-service teachers to expand their knowledge of astronomy and to provide them with additional resources for teaching astronomy. This work is supported in part by NSF EPSCoR grant OSR-9255223.

  3. Independent verification of the units of monitor for program diamond rapidarc treatments; Verificacion independiente de las unidades de monitor para tratamientos de rapidac con el programa Diamon. Consideraciones paracticas

    Energy Technology Data Exchange (ETDEWEB)

    Lliso Valverde, F.; Carmona Mesenguer, V.; Gimeno Olmos, J.; Garcia Martinez, T.; Pujades Claumarchiran, M. C.; Palomo Llinares, R.; Ballester Pallares, F.; Perez-Calatayud, J.

    2013-07-01

    The Diamond program is a useful tool that allows you to have a secondary verification of the calculations of the SP in complex treatments. the purpose of this paper is to describe the findings and practical aspects of our experience with the use of Diamond treatment with Rapid Arc (RA). (Author)

  4. Lake Roosevelt Fisheries Evaluation Program, Part B; Limnology, Primary Production, and Zooplankton in Lake Roosevelt, Washington, 1998 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Shields, John; Spotts, Jim; Underwood, Keith

    2002-11-01

    The Lake Roosevelt Fisheries Evaluation Program is the result of a merger between two projects, the Lake Roosevelt Monitoring Program (BPA No. 8806300) and the Lake Roosevelt Data Collection Project (BPA No. 9404300). These projects were merged in 1996 to continue work historically completed under the separate projects, and is now referred to as the Lake Roosevelt Fisheries Evaluation Program. The 1998 Annual Report, Part B. Limnology, Primary Production, and Zooplankton in Lake Roosevelt, Washington examined the limnology, primary production, and zooplankton at eleven locations throughout the reservoir. The 1998 research protocol required a continuation of the more complete examination of limnological parameters in Lake Roosevelt that began in 1997. Phytoplankton and periphyton speciation, phytoplankton and periphyton chlorophyll a analysis, complete zooplankton biomass analysis by taxonomic group, and an increased number of limnologic parameters (TDG, TDS, etc.) were examined and compared with 1997 results. Total dissolved gas levels were greatly reduced in 1998, compared with 1997, likely resulting from the relatively normal water year experienced in 1998. Mean water temperatures were similar to what was observed in past years, with a maximum of 22.7 C and a minimum of 2.6 C. Oxygen concentrations were also relatively normal, with a maximum of 16.6 mg/L, and a minimum of 0.9 mg/L. Phytoplankton in Lake Roosevelt was primarily composed of microplankton (29.6%), Cryptophyceae (21.7%), and Bacillriophyceae (17.0 %). Mean total phytoplankton chlorophyll a maximum concentration occurred in May (3.53 mg/m{sup 3}), and the minimum in January (0.39 mg/m{sup 3}). Phytoplankton chlorophyll a concentrations appear to be influenced by hydro-operations and temperature. Trophic status as indicated by phytoplankton chlorophyll a concentrations place Lake Roosevelt in the oligomesotrophic range. Periphyton colonization rates and biovolume were significantly greater at a depth

  5. An Evaluation of Micro-Credit Programs in Bosnia and Herzegovina Using Porter’s Diamond Model

    Directory of Open Access Journals (Sweden)

    Mohammad HAMAD

    2013-11-01

    Full Text Available The effective design and delivery of a microcredit program is difficult under any circumstance. Similarly, the task of microcredit institutions in Bosnia and Herzegovina that provide financial stability to its most impoverished members is very much complicated. The purpose of this paper is to explore competitive advantages that microcredit industry in Bosnia and Herzegovina has by using Porter's diamond model. The demonstration of the Diamond Model is used to explain the competitive advantage that the microcredit industry has in Bosnia and Herzegovina. To analyze the competitive advantages, secondary data were used from various institutional and governmental resources .The findings reflect that the meaningful objectives were set out by microcredit institutions in the country including objectively verifiable indicators of achievements. Among peers in Kosovo and in other Balkan regions (Albania, Croatia, Macedonia, Montenegro, Serbia, as well as peers similar in size and market outreach from Eastern Europe and Central Asia (ECA, the Bosnian microcredit institutions are some of the most highly leveraged. There is a clear upward trend in the median indicator for portfolio at risk between 2006 and 2008. The inflationary pressures that started at the end of 2007 in BH as well as the repercussions of the global 2008/2009 financial crisis have affected the repayment capacity of clients. From a policy perspective, the results suggest that in order to improve efficiency in the microcredit sector, and in the financial sector as a whole, a unified banking agency for the country must be established. Despite being hopeful for future, this doesn't seem likely to happen until the Bosnian Constitution is amended sometime in the future.

  6. 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.

  7. Lake Roosevelt Fisheries Evaluation Program; Meadow Creek vs. Lake Whatcom Stock Kokanee Salmon Investigations in Lake Roosevelt, 2001 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    McLellan, Holly; Scholz, Allan

    2002-03-01

    Lake Roosevelt has been stocked with Lake Whatcom stock kokanee since 1989 with the primary objective of creating a self-sustaining recreational fishery. Due to low return numbers, it was hypothesized a stock of kokanee, native to the upper Columbia River, might perform better than the coastal Lake Whatcom strain. Kokanee from Meadow Creek, a tributary of Kootenay Lake, British Columbia were selected as an alternative stock. Matched pair releases of Lake Whatcom and Meadow Creek kokanee were made from Sherman Creek Hatchery in late June 2000 and repeated in 2001. Stock performance between Lake Whatcom and Meadow Creek kokanee was evaluated using three performance measures; (1) the number of returns to Sherman Creek, the primary egg collection facility, (2) the number of returns to other tributaries and (3) the number of returns to the creel. Kokanee were collected during five passes through the reservoir via electrofishing, which included 87 tributary mouths during the fall of 2000 and 2001. Chi-square analysis indicated age two Meadow Creek kokanee returned to Sherman Creek in significantly higher numbers when compared to the Whatcom stock in 2000 ({chi}{sup 2} = 736.6; d.f. = 1; P < 0.01) and 2001 ({chi}{sup 2} = 156.2; d.f. = 1; P < 0.01). Reservoir wide recoveries of age two kokanee had similar results in 2000 ({chi}{sup 2} = 735.3; d.f. = 1; P < 0.01) and 2001 ({chi}{sup 2} = 150.1; d.f. = 1; P < 0.01). Six Lake Whatcom and seven Meadow Creek three year olds were collected in 2001. The sample size of three year olds was too small for statistical analysis. No kokanee were collected during creel surveys in 2000, and two (age three kokanee) were collected in 2001. Neither of the hatchery kokanee collected were coded wire tagged, therefore stock could not be distinguished. After two years of monitoring, neither Meadow Creek or Lake Whatcom kokanee appear to be capable of providing a run of three-year-old spawners to sustain stocking efforts. The small number of

  8. Lake Roosevelt Fisheries Evaluation Program; Meadow Creek vs. Lake Whatcom Stock Kokanee Salmon Investigations in Lake Roosevelt, Annual Report 2002.

    Energy Technology Data Exchange (ETDEWEB)

    McLellan, Holly

    2003-03-01

    Lake Whatcom, Washington kokanee have been stocked in Lake Roosevelt since 1987 with the primary objective of creating a self-sustaining fishery. Success has been limited by low recruitment to the fishery, low adult returns to hatcheries, and a skewed sex ratio. It was hypothesized that a stock native to the upper Columbia River might perform better than the coastal Lake Whatcom stock. Kokanee from Meadow Creek, a tributary of Kootenay Lake, British Columbia were selected as an alternative stock. Post smolts from each stock were released from Sherman Creek Hatchery in late June 2000 and repeated in 2001. Stock performance was evaluated using three measures; (1) number of returns to Sherman Creek, the primary egg collection facility, (2) the number of returns to 86 tributaries sampled and, (3) the number of returns to the creel. In two repeated experiments, neither Meadow Creek or Lake Whatcom kokanee appeared to be capable of providing a run of three-year old spawners to sustain stocking efforts. Less than 10 three-years olds from either stock were collected during the study period. Chi-square analysis indicated age two Meadow Creek kokanee returned to Sherman Creek and to other tributaries in significantly higher numbers when compared to the Lake Whatcom stock in both 2000 and 2001. However, preliminary data from the Spokane Tribe of Indians indicated that a large number of both stocks were precocial before they were stocked. The small number of hatchery three-year olds collected indicated that the current hatchery rearing and stocking methods will continue to produce a limited jacking run largely composed of precocious males and a small number of three-year olds. No kokanee from the study were collected during standard lake wide creel surveys. Supplemental creel data, including fishing derbies, test fisheries, and angler diaries, indicated anglers harvested two-year-old hatchery kokanee a month after release. The majority of the two-year old kokanee harvested

  9. National Status and Trends: Bioeffects Program - Sabine Lake, Texas Database

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The toxicity of sediments in Sabine Lake, Texas, and adjoining Intracoastal Waterway canals was determined as part of bioeffects assessment studies managed by NOAA's...

  10. A Citizen Science Program for Monitoring Lake Stages in Northern Wisconsin

    Science.gov (United States)

    Kretschmann, A.; Drum, A.; Rubsam, J.; Watras, C. J.; Cellar-Rossler, A.

    2011-12-01

    Historical data indicate that surface water levels in northern Wisconsin are fluctuating more now than they did in the recent past. In the northern highland lake district of Vilas County, Wisconsin, concern about record low lake levels in 2008 spurred local citizens and lake associations to form a lake level monitoring network comprising citizen scientists. The network is administered by the North Lakeland Discovery Center (NLDC, a local NGO) and is supported by a grant from the Citizen Science Monitoring Program of the Wisconsin Department of Natural Resources (WDNR). With technical guidance from limnologists at neighboring UW-Madison Trout Lake Research Station, citizen scientists have installed geographic benchmarks and staff gauges on 26 area lakes. The project engages citizen and student science participants including homeowners, non-profit organization member-participants, and local schools. Each spring, staff gauges are installed and referenced to fixed benchmarks after ice off by NLDC and dedicated volunteers. Volunteers read and record staff gauges on a weekly basis during the ice-free season; and maintain log books recording lake levels to the nearest 0.5 cm. At the end of the season, before ice on, gauges are removed and log books are collected by the NLDC coordinator. Data is compiled and submitted to a database management system, coordinated within the Wisconsin Surface Water Integrated Monitoring System (SWIMS), a statewide information system managed by the WDNR in Madison. Furthermore, NLDC is collaborating with the SWIMS database manager to develop data entry screens based on records collected by citizen scientists. This program is the first of its kind in Wisconsin to utilize citizen scientists to collect lake level data. The retention rate for volunteers has been 100% over the three years since inception, and the program has expanded from four lakes in 2008 to twenty-six lakes in 2011. NLDC stresses the importance of long-term monitoring and the

  11. Highland High School Vocational Television; a Salt Lake Schools Exemplary Vocational Program.

    Science.gov (United States)

    Nagle, LaMar C.

    The Highland High School (Salt Lake City, Utah) vocational television production program was designed to provide students with marketable skills in color television studio operation. Among the skills covered in the program were camera set-up and operation, video engineering, production switching, directing, television lighting, audio engineering,…

  12. An economic inquisition of water quality trading programs, with a case study of Jordan Lake, NC.

    Science.gov (United States)

    Motallebi, Marzieh; Hoag, Dana L; Tasdighi, Ali; Arabi, Mazdak; Osmond, Deanna L

    2017-05-15

    A water quality trading (WQT) program was promulgated in North Carolina to address water quality issues related to nutrients in the highly urbanizing Jordan Lake Watershed. Although WQT programs are appealing in theory, the concept has not proved feasible in several attempts between point and nonpoint polluters in the United States. Many application hurdles that create wedges between success and failure have been evaluated in the literature. Most programs, however, face multiple hurdles; eliminating one may not clear a pathway to success. Therefore, we identify and evaluate the combined impact of four different wedges including baseline, transaction cost, trading ratio, and trading cost in the Jordan Lake Watershed program. Unfortunately, when applied to the Jordan Lake program, the analysis clearly shows that a traditional WQT program will not be feasible or address nutrient management needs in a meaningful way. The hurdles individually would be difficult to overcome, but together they appear to be unsurmountable. This analysis shows that there is enough information to pre-identify potential hurdles that could inform policy makers where, and how, the concept might work. It would have saved time, energy, and financial resources if North Carolina had done so before embarking to implement their program in the Jordan Lake Watershed. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. 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.

  14. Evaluation of a rural demonstration program to increase seat belt use in the Great Lakes Region.

    Science.gov (United States)

    2009-03-01

    Six States in the Great Lakes Region (Region 5) participated in a Rural Demonstration Program to increase seat belt : use in rural areas and among high-risk occupants, such as young males and occupants of pickup trucks. These : efforts, which include...

  15. 46 CFR 45.33 - Diamond.

    Science.gov (United States)

    2010-10-01

    ... the upper edge of the deck line on each side with the center of the loadline mark at a distance below the deck line equal to the summer freeboard assigned under this part. (b) The width of each line in..., DEPARTMENT OF HOMELAND SECURITY (CONTINUED) LOAD LINES GREAT LAKES LOAD LINES Load Line Marks § 45.33 Diamond...

  16. Evaluation of the Navy Plaque Control Program, at Great Lakes.

    Science.gov (United States)

    1980-02-01

    I 0 Individual clinicians who practice plaque control with their patients receive great reward and sense of accomplishment when dental caries is...Navy Dental Corps (43). The program requirements included plaque control instruction given through individual or small group sessions. The sessions... plaque removal techniques; demonstration of sulcular methods of tooth cleansing with the toothbrush ; and instruction in the use of plaque disclosing

  17. Lake Roosevelt Fisheries Evaluation Program : Limnological and Fisheries Monitoring Annual Report 1999.

    Energy Technology Data Exchange (ETDEWEB)

    McLellan, Holly; Lee, Chuck; Scofield, Ben; Pavlik, Deanne

    1999-08-01

    The Grand Coulee Dam was constructed in 1939 without a fish ladder, which eliminated steelhead (Onchorhynchus mykiss), chinook salmon (O. twshwastica), coho salmon (O. kisutch) and sockeye salmon (O. nerka) from returning to approximately 1,835 km (1,140 miles) of natal streams and tributaries found in the upper Columbia River Drainage in the United States and Canada. The Pacific Northwest Electric Power Planning and Conservation Act of 1980 gave the Bonneville Power Administration (BPA), the authority and responsibility to use its legal and financial resources, 'to protect, mitigate, and enhance fish and wildlife to the extent affected by the development and operation of any hydroelectric project of the Columbia River and its tributaries. This is to be done in a manner consistent with the program adopted by the Northwest Power Planning Council (NWPPC), and the purposes of the Act' (NWPPC, 1987). With the phrase 'protect, mitigate and enhance', Congress signaled its intent that the NWPPC's fish and wildlife program should do more than avoid future hydroelectric damage to the basin's fish and wildlife. The program must also counter past damage, work toward rebuilding those fish and wildlife populations that have been harmed by the hydropower system, protect the Columbia Basin's fish and wildlife resources, and mitigate for harm caused by decades of hydroelectric development and operations. By law, this program is limited to measures that deal with impacts created by the development, operation and management of hydroelectric facilities on the Columbia River and its tributaries. However, off-site enhancement projects are used to address the effects of the hydropower system on fish and wildlife (NWPPC 1987). Resident game fish populations have been established in Franklin D. Roosevelt Lake, the reservoir behind Grand Coulee Dam, since the extirpation of anadromous fish species. The resident game fish populations are now responsible

  18. HPHT-treated diamonds diamonds forever

    CERN Document Server

    Dobrinets, Inga A; Zaitsev, Alexander M

    2013-01-01

    High-temperature and high-pressure treatment of diamond is becoming an important technology to elaborate diamonds. This is the first book providing a comprehensive review of the properties of HPHT-treated diamonds, based on the analysis of published data and the work of the authors. The book gives a detailed analysis of the physics of transformation of internal structures of diamonds subjected to HPHT treatment and discusses how these transformations can be detected using methods of optical microscopy and spectroscopy. It also gives practical recommendations for the recognition of HPHT-treated diamonds. The book is written in a language and terms which can be understood by a broad audience of physicists, mineralogists and gemologists.

  19. Steel Creek primary producers: Periphyton and seston, L-Lake/Steel Creek Biological Monitoring Program, January 1986--December 1991

    Energy Technology Data Exchange (ETDEWEB)

    Bowers, J.A. [Westinghouse Savannah River Co., Aiken, SC (United States); Toole, M.A.; van Duyn, Y. [Normandeau Associates Inc., New Ellenton, SC (United States)

    1992-02-01

    The Savannah River Site (SRS) encompasses 300 sq mi of the Atlantic Coastal Plain in west-central South Carolina. Five major tributaries of the Savannah River -- Upper Three Runs Creek, Four Mile Creek, Pen Branch, Steel Creek, and Lower Three Runs Creek -- drain the site. In 1985, L Lake, a 400-hectare cooling reservoir, was built on the upper reaches of Steel Creek to receive effluent from the restart of L-Reactor and to protect the lower reaches from thermal impacts. The Steel Creek Biological Monitoring Program was designed to assess various components of the system and identify and changes due to the operation of L-Reactor or discharge from L Lake. An intensive ecological assessment program prior to the construction of the lake provided baseline data with which to compare data accumulated after the lake was filled and began discharging into the creek. The Department of Energy must demonstrate that the operation of L-Reactor will not significantly alter the established aquatic ecosystems. This report summarizes the results of six years` data from Steel Creek under the L-Lake/Steel Creek Monitoring Program. L Lake is discussed separately from Steel Creek in Volumes NAI-SR-138 through NAI-SR-143.

  20. Water-saving interventions assessment framework: an application for the Urmia Lake Restoration Program

    Science.gov (United States)

    Shadkam, Somayeh; Oel, Pieter; Kabat, Pavel; Ludwig, Fulco

    2017-04-01

    Increasing water demand often results in unsustainable water use leaving insufficient amounts of water for sustaining natural environments. Therefore, to save natural resources water-saving interventions have been introduced to the environmental policy agenda in many (semi)-arid regions. Many policies, however, have failed reaching their objectives to increase water availability for the environment. This calls for a comprehensive tool to assess water-saving policies. Therefore, this study introduces a constructive framework to assess the policies by estimating five components: 1) Total water demand under socio-economic scenarios, 2) Water supply under climate change scenarios, 3) Water withdrawal for different sectors, 4) Water depletion and 5) Environmental flow. The framework, was applied to assess Urmia Lake Restoration Program (ULRP), which aims to restore the drying Urmia Lake in north-western Iran by increasing the lake inflow by 3.1×106m3yr-1. Results suggest that although the ULRP helps to increase inflow by up to 57% it is unlikely to fully reach its target. The analysis shows that there are three main reasons for the potential poor performance. The first reason is decreasing return flows due to increasing irrigation efficiency. This means that the expected increase in lake inflow volume is smaller than the volume saved by increasing irrigation efficiency. The second reason is increased depletion which is due to neglecting the fact that agricultural water demand is currently higher than available water for agriculture. As a result, increasing water use efficiency may result in increased water depletion. The third reason is ignoring the potential impact of climate change, which might decrease future water availability by 3% to 15%. Our analysis suggests that to reach the intervention target, measures need to focus on reducing Water demand and Water depletion rather than on reducing Water withdrawals. The assessment framework can be used to comprehensively

  1. 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.

  2. Merit Pay in Arkansas: An Evaluation of the Cobra Pride Incentive Program in the Fountain Lake School District

    Science.gov (United States)

    Jensen, Nathan C.

    2012-01-01

    Starting in the 2010-11, administrators at the Fountain Lake School District implemented the Cobra Pride Incentive Program (CPIP), a merit pay program designed to financially reward all school employees with year-end bonuses primarily for significant improvements in student achievement. At the conclusion of the 2010-11 school year, over $800,000…

  3. 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.

  4. 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

  5. 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.

  6. Designing and Managing Public Housing Self-Sufficiency Programs: The Youngs Lake Commons Program

    Science.gov (United States)

    Kleit, Rachel Garshick

    2004-01-01

    This article evaluates an experimental public housing self-sufficiency program that encourages home ownership among low-income families. A quasi-experimental design, in combination with focus groups, records review, and key informant interviews, provides data to focus on four questions: (a) Do these programs simply accelerate move-outs for those…

  7. Lake County Banner : Federal Agency Would Undertake Extensive Program on Reelfoot

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This document covers extensive plans contained in a report covering contemplated improvement work on Reelfoot Lake and involving joint control management of the lake...

  8. Great Lakes maritime education program for K-12 teachers, year 2.

    Science.gov (United States)

    2012-02-01

    Michigan Technological University has led an educational/outreach effort for the Great Lake Maritime Research Institute since 2006. : Despite Michigan Techs relative isolation and long distance from most locations in the Great Lakes Basin, every s...

  9. Principles in sampling design, lessons, and recommendations from a multi-year, multi-port surveillance program in Lake Superior

    Science.gov (United States)

    We evaluated a pilot aquatic invasive species (AIS) early detection monitoring program in Lake Superior that was designed to detect newly-introduced fishes. We established survey protocols for three major ports (Duluth-Superior, Sault Ste. Marie, Thunder Bay), and designed an ada...

  10. 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.

  11. 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

  12. Lake Roosevelt Fisheries Evaluation Program : Lake Whatcom Kokanee Salmon (Oncorhynchus nerka kennerlyi) : Investigations in Lake Roosevelt Annual Report 1999-2000.

    Energy Technology Data Exchange (ETDEWEB)

    McLellan, Holly J.; Scholz, Allan T.; McLellan, Jason G.; Tilson, Mary Beth

    2001-07-01

    Lake Whatcom stock kokanee have been planted in Lake Roosevelt since 1988 with the primary goal of establishing a self-sustaining fishery. Returns of hatchery kokanee to egg collection facilities and recruitment to the creel have been minimal. Therefore, four experiments were conducted to determine the most appropriate release strategy that would increase kokanee returns. The first experiment compared morpholine and non-morpholine imprinted kokanee return rates, the second experiment compared early and middle run Whatcom kokanee, the third experiment compared early and late release dates, and the fourth experiment compared three net pen release strategies: Sherman Creek hatchery vs. Sherman Creek net pens, Colville River net pens vs. Sherman Creek net pens, and upper vs. lower reservoir net pen releases. Each experiment was tested in three ways: (1) returns to Sherman Creek, (2) returns to other tributaries throughout the reservoir, and (3) returns to the creel. Chi-square analysis of hatchery and tributary returns indicated no significant difference between morpholine imprinted and non-imprinted fish, early run fish outperformed middle run fish, early release date outperformed late release fish, and the hatchery outperformed all net pen releases. Hatchery kokanee harvest was estimated at 3,323 fish, which was 33% of the total harvest. Return rates (1998 = 0.52%) of Whatcom kokanee were low indicating an overall low performance that could be caused by high entrainment, predation, and precocity. A kokanee stock native to the upper Columbia, as opposed to the coastal Whatcom stock, may perform better in Lake Roosevelt.

  13. STABLE DIAMOND GRINDING

    Directory of Open Access Journals (Sweden)

    Yury Gutsalenko

    2010-06-01

    Full Text Available The paper generalizes on the one hand theory of kinematic-geometrical simulation of grinding processes by means of tools with working part as binding matrix with abrasive grains located in it in random manner, for example diamond grains, and on the other hand practical performance of combined grinding process, based on introduction of additional energy as electric discharges and called by the organization-developer (Kharkov Polytechnic Institute «diamond-spark grinding» as applied to processing by means of diamond wheel. Implementation of diamond-spark grinding technologies on the basis of developed generalized theoretical approach allows to use the tool with prescribed tool-life, moreover to make the most efficient use of it up to full exhausting of tool-life, determined by diamond-bearing thickness. Development is directed forward computer-aided manufacturing.

  14. Forecasting Water Level Fluctuations of Urmieh Lake Using Gene Expression Programming and Adaptive Neuro-Fuzzy Inference System

    Directory of Open Access Journals (Sweden)

    Sepideh Karimi

    2012-06-01

    Full Text Available Forecasting lake level at various prediction intervals is an essential issue in such industrial applications as navigation, water resource planning and catchment management. In the present study, two data driven techniques, namely Gene Expression Programming and Adaptive Neuro-Fuzzy Inference System, were applied for predicting daily lake levels for three prediction intervals. Daily water-level data from Urmieh Lake in Northwestern Iran were used to train, test and validate the used techniques. Three statistical indexes, coefficient of determination, root mean square error and variance accounted for were used to assess the performance of the used techniques. Technique inter-comparisons demonstrated that the GEP surpassed the ANFIS model at each of the prediction intervals. A traditional auto regressive moving average model was also applied to the same data sets; the obtained results were compared with those of the data driven approaches demonstrating superiority of the data driven models to ARMA.

  15. Ionoluminescence of diamond, synthetic diamond and simulants

    Energy Technology Data Exchange (ETDEWEB)

    Calvo del Castillo, H. [Departamento de Geologia y Geoquimica, Facultad de Ciencias, Universidad Autonoma de Madrid, Ctra de Colmenar km 15, Madrid 27049 (Spain); Instituto de Fisica, Universidad Nacional Autonoma de Mexico, Circuito de la Investigacion Cientifica s/n, Ciudad Universitaria, Ciudad de Mexico 04519, Mexico, DF (Mexico); Ruvalcaba-Sil, J.L. [Instituto de Fisica, Universidad Nacional Autonoma de Mexico, Circuito de la Investigacion Cientifica s/n, Ciudad Universitaria, Ciudad de Mexico 04519, Mexico, DF (Mexico); Barboza-Flores, M. [Centro de Investigacio en Fisica, Universidad de Sonora, Apartado postal 5-088, Hermosillo, Sonora 83190 (Mexico); Belmont, E. [Instituto de Fisica, Universidad Nacional Autonoma de Mexico, Circuito de la Investigacion Cientifica s/n, Ciudad Universitaria, Ciudad de Mexico 04519, Mexico, DF (Mexico); Calderon, T. [Departamento de Geologia y Geoquimica, Facultad de Ciencias, Universidad Autonoma de Madrid, Ctra de Colmenar km 15, Madrid 27049 (Spain)], E-mail: tomas.calderon@uam.es

    2007-09-21

    Ionoluminescence (IL) spectra of diamond (natural samples and synthetic CVD) and its more common synthetic simulates such as sapphire, spinel, cubic zirconia, strontium titanate and yttrium aluminium garnet (YAG: Er) will be discussed here in order to support some criteria that will allow to distinguish between them. While diamond shows emission bands due to nitrogen defects, simulants feature d-transition metals and rare earths such as Cr{sup 3+}, Mn{sup 2+}, Fe{sup 3+}, Ti{sup 3+} and Er{sup 3+} emissions.

  16. Lake Roosevelt Fisheries Evaluation Program; Movements and Growth of Marked Walleye Recaptured in Lake Roosevelt, 2000-2001 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    McLellan, Holly; Scholz, Allan

    2002-03-01

    Walleye (Stizostedion vitreum) have been marked with floy tags in Lake Roosevelt since 1997 to estimate abundance, distribution and movement trends. In 2000, walleye were collected and marked during the spawning run in the Spokane River through electrofishing and angling to supplement movement and growth data collected in previous years. Walleye were also collected and marked during the 2000 and 2001 Kettle Falls Governor's Cup Walleye Tournaments. Seventy-six tag returns were recovered in 2000 and twenty-three in 2001. Walleye migrated into the Spokane River to spawn in mid April and early May. The majority of marked walleye were recovered within 25 km of their original marking location, with a few traveling long distances between recovery locations. Data also verified earlier results that walleye establish summer home ranges. Some walleye remained in the Spokane River, while others moved downstream, or upstream after entering the mainstem of Lake Roosevelt. Those moving upstream moved as far north as Keenlyside Dam in British Columbia (245 km). Growth data indicated similar trends exhibited in the past. Walleye growth and mortality rates were consistent with other walleye producing waters. Walleye condition was slightly below average when compared to other systems.

  17. Forecasting Shaharchay River Flow in Lake Urmia Basin using Genetic Programming and M5 Model Tree

    Directory of Open Access Journals (Sweden)

    S. Samadianfard

    2017-01-01

    Full Text Available Introduction: Precise prediction of river flows is the key factor for proper planning and management of water resources. Thus, obtaining the reliable methods for predicting river flows has great importance in water resource engineering. In the recent years, applications of intelligent methods such as artificial neural networks, fuzzy systems and genetic programming in water science and engineering have been grown extensively. These mentioned methods are able to model nonlinear process of river flows without any need to geometric properties. A huge number of studies have been reported in the field of using intelligent methods in water resource engineering. For example, Noorani and Salehi (23 presented a model for predicting runoff in Lighvan basin using adaptive neuro-fuzzy network and compared the performance of it with neural network and fuzzy inference methods in east Azerbaijan, Iran. Nabizadeh et al. (21 used fuzzy inference system and adaptive neuro-fuzzy inference system in order to predict river flow in Lighvan river. Khalili et al. (13 proposed a BL-ARCH method for prediction of flows in Shaharchay River in Urmia. Khu et al. (16 used genetic programming for runoff prediction in Orgeval catchment in France. Firat and Gungor (11 evaluated the fuzzy-neural model for predicting Mendes river flow in Turkey. The goal of present study is comparing the performance of genetic programming and M5 model trees for prediction of Shaharchay river flow in the basin of Lake Urmia and obtaining a comprehensive insight of their abilities. Materials and Methods: Shaharchay river as a main source of providing drinking water of Urmia city and agricultural needs of surrounding lands and finally one of the main input sources of Lake Urmia is quite important in the region. For obtaining the predetermined goals of present study, average monthly flows of Shaharchay River in Band hydrometric station has been gathered from 1951 to 2011. Then, two third of mentioned

  18. Statistical analysis of the water-quality monitoring program, Upper Klamath Lake, Oregon, and optimization of the program for 2013 and beyond

    Science.gov (United States)

    Eldridge, Sara L. Caldwell; Wherry, Susan A.; Wood, Tamara M.

    2014-01-01

    Upper Klamath Lake in south-central Oregon has become increasingly eutrophic over the past century and now experiences seasonal cyanobacteria-dominated and potentially toxic phytoplankton blooms. Growth and decline of these blooms create poor water-quality conditions that can be detrimental to fish, including two resident endangered sucker species. Upper Klamath Lake is the primary water supply to agricultural areas within the upper Klamath Basin. Water from the lake is also used to generate power and to enhance and sustain downstream flows in the Klamath River. Water quality in Upper Klamath Lake has been monitored by the Klamath Tribes since the early 1990s and by the U.S. Geological Survey (USGS) since 2002. Management agencies and other stakeholders have determined that a re-evaluation of the goals for water-quality monitoring is warranted to assess whether current data-collection activities will continue to adequately provide data for researchers to address questions of interest and to facilitate future natural resource management decisions. The purpose of this study was to (1) compile an updated list of the goals and objectives for long-term water-quality monitoring in Upper Klamath Lake with input from upper Klamath Basin stakeholders, (2) assess the current water-quality monitoring programs in Upper Klamath Lake to determine whether existing data-collection strategies can fulfill the updated goals and objectives for monitoring, and (3) identify potential modifications to future monitoring plans in accordance with the updated monitoring objectives and improve stakeholder cooperation and data-collection efficiency. Data collected by the Klamath Tribes and the USGS were evaluated to determine whether consistent long-term trends in water-quality variables can be described by the dataset and whether the number and distribution of currently monitored sites captures the full range of environmental conditions and the multi-scale variability of water

  19. Lake Roosevelt Fisheries Evaluation Program, Part A; Fisheries Creel Survey and Population Status Analysis, 1998 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Spotts, Jim; Shields, John; Underwood, Keith

    2002-05-01

    The Lake Roosevelt Fisheries Evaluation Program is the result of a merger between two projects, the Lake Roosevelt Monitoring Program (BPA No. 8806300) and the Lake Roosevelt Data Collection Project (BPA No. 9404300). These projects were merged in 1996 to continue work historically completed under the separate projects, and is now referred to as the Lake Roosevelt Fisheries Evaluation Program. Creel and angler surveys estimated that anglers made 196,775 trips to Lake Roosevelt during 1998, with an economic value of $8.0 million dollars, based on the Consumer Price Index (CPI). In 1998 it was estimated that 9,980 kokanee salmon, 226,809 rainbow trout, 119,346 walleye, and over 14,000 smallmouth bass and other species were harvested. Creel data indicates that hatchery reared rainbow trout contribute substantially to the Lake Roosevelt fishery. The contribution of kokanee salmon to the creel has not met the expectations of fishery managers to date, and is limited by entrainment from the reservoir, predation, and possible fish culture obstacles. The 1998 Lake Roosevelt Fisheries Creel and Population Analysis Annual Report includes analyses of the relative abundance of fish species, and reservoir habitat relationships (1990-1998). Fisheries surveys (1990-1998) indicate that walleye and burbot populations appear to be increasing, while yellow perch, a preferred walleye prey species, and other prey species are decreasing in abundance. The long term decreasing abundance of yellow perch and other prey species are suspected to be the result of the lack of suitable multiple reservoir elevation spawning and rearing refugia for spring spawning reservoir prey species, resulting from seasonal spring-early summer reservoir elevation manipulations, and walleye predation. Reservoir water management is both directly, and indirectly influencing the success of mitigation hatchery production of kokanee salmon and rainbow trout. Tag return data suggested excessive entrainment occurred in

  20. Lake Roosevelt Fisheries Evaluation Program : Meadow Creek vs. Lake Whatcom Stock Kokanee Salmon Investigations in Lake Roosevelt Annual Report 2000-2001.

    Energy Technology Data Exchange (ETDEWEB)

    McLellan, Holly J.; Scholz, Allan T.

    2001-07-01

    Lake Roosevelt has been stocked with Whatcom stock kokanee since 1989 to mitigate for anadromous salmon losses caused by the construction of Grand Coulee Dam. The primary objective of the hatchery plantings was to create a self-sustaining recreational fishery. Due to low return numbers, it was hypothesized a native stock of kokanee might perform better than the coastal Whatcom strain. Therefore, kokanee from Meadow Creek, a tributary of Kootenay Lake, British Columbia were selected as an alternative stock. Matched pair releases of Whatcom stock and Meadow Creek kokanee were made from Sherman Creek in late June 2000. Stock performance between Lake Whatcom and Meadow Creek kokanee was evaluated through three performance measures (1) returns to Sherman Creek, the primary egg collection facility, (2) returns to other tributaries, indicating availability for angler harvest, and (3) returns to the creel. A secondary objective was to evaluate the numbers collected at downstream fish passage facilities. Age 2 kokanee were collected during five passes through the reservoir, which included 89 tributaries between August 17th and November 7th, 2000. Sherman Creek was sampled once a week because it was the primary egg collection location. A total of 2,789 age 2 kokanee were collected, in which 2,658 (95%) were collected at Sherman Creek. Chi-square analysis indicated the Meadow Creek kokanee returned to Sherman Creek in significantly higher numbers compared to the Whatcom stock ({chi}{sup 2} = 734.4; P < 0.01). Reservoir wide recoveries indicated similar results ({chi}{sup 2} = 733.1; P < 0.01). No age 2 kokanee were collected during creel surveys. Age 3 kokanee are expected to recruit to the creel in 2001. No age 2 kokanee were collected at the fish passage facilities due to a 170 mm size restriction at the fish passage centers. Age 3 kokanee are expected to be collected at the fish passage centers during 2001. Stock performance cannot be properly evaluated until 2001, when

  1. Fabrication of diamond shells

    Science.gov (United States)

    Hamza, Alex V.; Biener, Juergen; Wild, Christoph; Woerner, Eckhard

    2016-11-01

    A novel method for fabricating diamond shells is introduced. The fabrication of such shells is a multi-step process, which involves diamond chemical vapor deposition on predetermined mandrels followed by polishing, microfabrication of holes, and removal of the mandrel by an etch process. The resultant shells of the present invention can be configured with a surface roughness at the nanometer level (e.g., on the order of down to about 10 nm RMS) on a mm length scale, and exhibit excellent hardness/strength, and good transparency in the both the infra-red and visible. Specifically, a novel process is disclosed herein, which allows coating of spherical substrates with optical-quality diamond films or nanocrystalline diamond films.

  2. 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.

  3. Quantum engineering: Diamond envy

    Science.gov (United States)

    Nunn, Joshua

    2013-03-01

    Nitrogen atoms trapped tens of nanometres apart in diamond can now be linked by quantum entanglement. This ability to produce and control entanglement in solid systems could enable powerful quantum computers.

  4. CVD diamond pixel development

    CERN Document Server

    Stone, R; Koeth, T W; Perera, L P; Schnetzer, S; Worm, S

    2002-01-01

    Pixel detectors using synthetic diamond are an attractive alternative to silicon for use in radiation harsh environments such as at the Large Hadron Collider (LHC). Recent test beam results using Compact Muon Solenoid pixel readout electronics are presented, which demonstrate a hit efficiency of 95% and position resolution of 31 mu m for a diamond pixel sensor with 125 * 125 mu m/sup 2/ pitch. (5 refs).

  5. Cryotribology of diamond and graphite

    Energy Technology Data Exchange (ETDEWEB)

    Iwasa, Yukikazu; Ashaboglu, A.F.; Rabinowicz, E.R. [Francis Bitter Magnet Lab., Cambridge, MA (United States)

    1996-12-31

    An experimental study was carried out on the tribological behavior of materials of interest in cryogenic applications, focusing on diamond and graphite. Both natural diamond (referred in the text as diamond) and chemical-vapor-deposition (CVD) diamond (CVD-diamond) were used. The experiment was carried out using a pin-on-disk tribometer capable of operating at cryogenic temperatures, from 4.2 to 293 K. Two basic scenarios of testing were used: (1) frictional coefficient ({mu}) vs velocity (v) characteristics at constant temperatures; (2) {mu} vs temperature (T) behavior at fixed sliding speeds. For diamond/CVD-diamond, graphite/CVD-diamond, stainless steel/CVD-diamond pairs, {mu}`s are virtually velocity independent. For each of diamond/graphite, alumina/graphite, and graphite/graphite pairs, the {partial_derivative}{mu}/{partial_derivative}v characteristic is favorable, i.e., positive. For diamond/CVD-diamond and graphite/CVD-diamond pairs, {mu}`s are nearly temperature independent between in the range 77 - 293 K. Each {mu} vs T plot for pin materials sliding on graphite disks has a peak at a temperature in the range 100 - 200 K.

  6. 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.

  7. 2016 RFA for Great Lakes Long-Term Biology Monitoring Program: Phytoplankton Component

    Science.gov (United States)

    This Request for Applications solicits applications from eligible entities for a cooperative agreement to be awarded for a project to continue the long-term monitoring of phytoplankton in the open waters of the Great Lakes.

  8. Diamond pixel modules

    CERN Document Server

    Gan, K K; Robichaud, A; Potenza, R; Kuleshov, S; Kagan, H; Kass, R; Wermes, N; Dulinski, W; Eremin, V; Smith, S; Sopko, B; Olivero, P; Gorisek, A; Chren, D; Kramberger, G; Schnetzer, S; Weilhammer, P; Martemyanov, A; Hugging, F; Pernegger, H; Lagomarsino, S; Manfredotti, C; Mishina, M; Trischuk, W; Dobos, D; Cindro, V; Belyaev, V; Duris, J; Claus, G; Wallny, R; Furgeri, A; Tuve, C; Goldstein, J; Sciortino, S; Sutera, C; Asner, D; Mikuz, M; Lo Giudice, A; Velthuis, J; Hits, D; Griesmayer, E; Oakham, G; Frais-Kolbl, H; Bellini, V; D'Alessandro, R; Cristinziani, M; Barbero, M; Schaffner, D; Costa, S; Goffe, M; La Rosa, A; Bruzzi, M; Schreiner, T; de Boer, W; Parrini, G; Roe, S; Randrianarivony, K; Dolenc, I; Moss, J; Brom, J M; Golubev, A; Mathes, M; Eusebi, R; Grigoriev, E; Tsung, J W; Mueller, S; Mandic, I; Stone, R; Menichelli, D

    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 1.8 x 10(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 m...

  9. The carbonado diamond conundrum

    Science.gov (United States)

    McCall, G. J. H.

    2009-04-01

    The reviewer presents the results of a literature search on the enigmatic occurrences of carbonado; a form (but not the only form) of polycrystalline diamond, which is mined for industrial diamonds. The principal occurrences are in Brazil, the Central African Republic (CAR) and Siberia (Yakutia). In the latter the name yakutite has been coined, but, though there are differences between these polycrystalline diamonds and the Brazil/CAR minerals, they would seem to be little more significant than differences within the 'Gondwana' occurrences, and 'yakutite' should probably be regarded as another name for carbonado. Most occurrences are in placers and the minerals have probably been recycled more than once by sedimentary processes, the ultimate source being unknown. Polycrystalline diamond has been described from the Udachnaya pipe, Yakutia and, though it is strictly framesite (defined as an eruptive pipe variety of carbonado), it differs little from other carbonados. The fact that all occurrences known are in areas with kimberlites and gem diamond developments present, suggests that carbonado does stem from terrestrial eruptive processes, though not necessarily kimberlite pipes. Nevertheless, this can be only a provisional, personal conclusion, there is much contradictory evidence in the literature. The evidence of subjection to radiogenic agencies in CAR carbonados seems to be unexplained, but it may be a secondary effect and not present in all carbonados. This is a conundrum which still calls for much more research.

  10. Making Diamond in the Laboratory

    Science.gov (United States)

    Strong, Herbert

    1975-01-01

    Discusses the graphite to diamond transformation and a phase diagram for carbon. Describes high temperature-higher pressure experimental apparatus and growth of diamonds from seed crystals. Reviews properties of the diamond which suggest uses for the synthetic product. Illustrations with text. (GH)

  11. Diamond turning microstructure optical components

    Science.gov (United States)

    Jiang, Wenda

    2009-05-01

    Microstructure optical components in the form of Fresnel, TIR, microgroove, micro lens array provide a lot design freedom for high compact optical systems. It is a key factor which enables the cutting edge technology for telecommunication, surveillance and high-definition display system. Therefore, the demand of manufacturing such element is rapidly increasing. These elements usually contain high precision, tiny structure and complex form, which have posed many new challenges for tooling, programming as well as ultra-precision machining. To cope with the fast development of the technology and meet the increasing demand of the market, we have developed our own manufacturing process to fabricate microstructure optical components by way of Diamond tuning, Shaping, Raster cutting, Slow Slide Servo (SSS), Diamond milling and Post polishing. This paper is to focus on how we employed these methods to produce complex prototype of microstructure optical components and precision mold inserts which either contains aspheric lens array or freeform V grooves. The high quality finish of these surfaces meets application requirements. Measurement results are presented. Advantages and disadvantages of these methods are compared and discussed in the paper.

  12. Mechanically induced degradation of diamond

    CERN Document Server

    Bouwelen, F V

    1996-01-01

    bombardment a mechanically induced graphitisation, as opposed to a thermally activated transformation, may occur locally on collision with the CVD diamond. Two types of diamond-graphite interfaces were observed: (111) planes of diamond parallel to the a-b planes of graphite and (111) planes of diamond, smoothly within the plane, connected to a-b planes of graphite. The thesis concludes with a summary of the results, conclusions and recommendations for further work. This thesis deals with the wear of diamond occurring during frictional sliding contact between diamonds. In the introduction, a literature survey on friction, wear and polishing behaviour of diamond, with some emphasis on the anisotropy, is presented and earlier work is discussed. A review of the existing theories is given, a new hypothesis is proposed and key-experiments for verification are identified. Electron microscopical techniques such as High Resolution Electron Microscopy (HREM) imaging and Electron Energy Loss Spectroscopy are described a...

  13. Computer program to simulate the salt balance between the north and south parts of Great Salt Lake, Utah

    Science.gov (United States)

    Waddell, K.M.; Bolke, E.L.

    1975-01-01

    This report presents a computer simulation program that was used by Waddell and Bolke (1973) to predict the salt balance between the north and south parts of Great Salt Lake, Utah, for either existing or modified culvert openings (fig. 1). The development of the program, its accuracy and limitations, are described in the above report, which was prepared as part of a study conducted by the U.S. Geological Survey in cooperation with the Utah Geological and Mineral Survey. Users of this program should consider it an addendum to the report by Waddell and Bolke (1973).Although this program has been tested by its contributor, no warranty, expressed or implied, is made by the contributor or the Government, as to the functioning of the program and related program material, nor shall the fact of distribution constitute any such warranty, and no responsibility is assumed by the contributor or the Government, in connection therewith.The FORTRAN IV program listing (table 1) defines the constants and variables necessary for understanding the mechanics and the output from the program.

  14. CVD diamond - fundamental phenomena

    Energy Technology Data Exchange (ETDEWEB)

    Yarbrough, W.A. [Pennsylvania State Univ., University Park (United States)

    1993-01-01

    This compilation of figures and diagrams addresses the basic physical processes involved in the chemical vapor deposition of diamond. Different methods of deposition are illustrated. For each method, observations are made of the prominent advantages and disadvantages of the technique. Chemical mechanisms of nucleation are introduced.

  15. National Water-Quality Assessment Program: Great Salt Lake basins study unit

    Science.gov (United States)

    Waddell, Kidd M.

    1999-01-01

    The Great Salt Lake Basins NAWQA study will increase the scientific understanding of the factors that influence surface- and ground-water quality. This information will benefit water-resources managers that need, but often lack, the data required to implement effective water-quality management actions and evaluate long-term changes in water quality.

  16. Lake Mead--clear and vital

    Science.gov (United States)

    Wessells, Stephen M.; Rosen, Michael

    2013-01-01

    Lake Mead – Clear and Vital” is a 13 minute documentary relating the crucial role of science in maintaining high water quality in Lake Mead. The program was produced coincident with release of the Lakes Mead and Mohave Circular a USGS publication covering past and on-going research in the lakes and tributaries of the Lake Mead National Recreation Area.

  17. Lake Roosevelt Fisheries Evaluation Program; Evaluation of Limiting Factors for Stocked Kokanee and Rainbow Trout in Lake Roosevelt, Washington, 1999 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Baldwin, Casey; Polacek, Matt

    2009-03-01

    Hatchery supplementation of kokanee Oncorhynchus nerka and rainbow trout O. mykiss has been the primary mitigation provided by Bonneville Power Administration for loss of anadromous fish to the waters above Grand Coulee Dam (GCD). The hatchery program for rainbow trout has consistently met management goals and provided a substantial contribution to the fishery; however, spawner returns and creel survey results for kokanee have been below management goals. Our objective was to identify factors that limit limnetic fish production in Lake Roosevelt by evaluating abiotic conditions, food limitations, piscivory, and entrainment. Dissolved oxygen concentration was adequate throughout most of the year; however, levels dropped to near 6 mg/L in late July. For kokanee, warm water temperatures during mid-late summer limited their nocturnal distribution to 80-100 m in the lower section of the reservoir. Kokanee spawner length was consistently several centimeters longer than in other Pacific Northwest systems, and the relative weights of rainbow trout and large kokanee were comparable to national averages. Large bodied daphnia (> 1.7 mm) were present in the zooplankton community during all seasons indicating that top down effects were not limiting secondary productivity. Walleye Stizostedion vitreum were the primary piscivore of salmonids in 1998 and 1999. Burbot Lota lota smallmouth bass Micropterus dolomieui, and northern pikeminnow Ptychocheilus oregonensis preyed on salmonids to a lesser degree. Age 3 and 4 walleye were responsible for the majority (65%) of the total walleye consumption of salmonids. Bioenergetics modeling indicated that reservoir wide consumption by walleye could account for a 31-39% loss of stocked kokanee but only 6-12% of rainbow trout. Size at release was the primary reason for differential mortality rates due to predation. Entrainment ranged from 2% to 16% of the monthly abundance estimates of limnetic fish, and could account for 30% of total

  18. 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.

  19. Evaluation of water-quality data and monitoring program for Lake Travis, near Austin, Texas

    Science.gov (United States)

    Rast, Walter; Slade, Raymond M.

    1998-01-01

    Statistical analyses were made of selected water-quality properties and constituents for Lake Travis, northwest of Austin in central Texas. Objectives for the evaluation were: (1) to provide information on levels of selected water-quality properties or constituents to use as reference values for assessing the future effectiveness of the Lake Travis Nonpoint-Source Control ordinance of the Lower Colorado River Authority; and (2) to determine whether water-quality constituents at any of the sampling sites are statistically redundant with other sites and, thus, can be discontinued without loss of information. The data were grouped into two periods—the thermally stratified period (May through November) and the mixed period (December through April).

  20. 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 ...

  1. Diamond turning of glass

    Energy Technology Data Exchange (ETDEWEB)

    Blackley, W.S.; Scattergood, R.O.

    1988-12-01

    A new research initiative will be undertaken to investigate the critical cutting depth concepts for single point diamond turning of brittle, amorphous materials. Inorganic glasses and a brittle, thermoset polymer (organic glass) are the principal candidate materials. Interrupted cutting tests similar to those done in earlier research are Ge and Si crystals will be made to obtain critical depth values as a function of machining parameters. The results will provide systematic data with which to assess machining performance on glasses and amorphous materials

  2. Steel Creek fish: L-Lake/Steel Creek Biological Monitoring Program, January 1986--December 1987

    Energy Technology Data Exchange (ETDEWEB)

    Paller, M.H.; Heuer, J.H.; Kissick, L.A.

    1988-03-01

    Fish samples were collected from Steel Creek during 1986 and 1987 following the impoundment of the headwaters of the stream to form L-Lake, a cooling reservoir for L-Reactor which began operating late in 1985. Electrofishing and ichthyoplankton sample stations were located throughout the creek. Fykenetting sample stations were located in the creek mouth and just above the Steel Creek swamp. Larval fish and fish eggs were collected with 0.5 m plankton nets. Multivariate analysis of the electrofishing data suggested that the fish assemblages in Steel Creek exhibited structural differences associated with proximity to L-Lake, and habitat gradients of current velocity, depth, and canopy cover. The Steel Creek corridor, a lotic reach beginning at the base of the L-Lake embankment was dominated by stream species and bluegill. The delta/swamp, formed where Steel Creek enters the Savannah River floodplain, was dominated by fishes characteristic of slow flowing waters and heavily vegetated habitats. The large channel draining the swamp supported many of the species found in the swamp plus riverine and anadromous forms.

  3. Conversion of fullerenes to diamond

    Science.gov (United States)

    Gruen, Dieter M.

    1993-01-01

    A method of forming synthetic diamond on a substrate is disclosed. The method involves providing a substrate surface covered with a fullerene or diamond coating, positioning a fullerene in an ionization source, creating a fullerene vapor, ionizing fullerene molecules, accelerating the fullerene ions to energies above 250 eV to form a fullerene ion beam, impinging the fullerene ion beam on the substrate surface and continuing these steps to obtain a diamond thickness on the substrate.

  4. Conversion of fullerenes to diamonds

    Science.gov (United States)

    Gruen, Dieter M.

    1995-01-01

    A method of forming synthetic diamond or diamond-like films on a substrate surface. The method involves the steps of providing a vapor selected from the group of fullerene molecules or an inert gas/fullerene molecule mixture, providing energy to the fullerene molecules consisting of carbon-carbon bonds, the energized fullerene molecules breaking down to form fragments of fullerene molecules including C.sub.2 molecules and depositing the energized fullerene molecules with C.sub.2 fragments onto the substrate with farther fragmentation occurring and forming a thickness of diamond or diamond-like films on the substrate surface.

  5. The ATLAS Diamond Beam Monitor

    CERN Document Server

    Cerv, M

    2014-01-01

    The ATLAS Diamond Beam Monitor is a novel charged-particle detector. It will be used in the ATLAS experiment to measure luminosity and beam backgrounds. The monitor’s pCVD diamond sensors are instrumented with pixellated FE-I4 front-end chips. The CVD diamond sensor material was chosen to ensure long-term durability of the sensors in a radiation-hard environment. This document describes the principles of luminosity measurements. It is then explained how the Diamond Beam Monitor will carry out this task.

  6. Topomineralogy of the Siberian diamonds

    Science.gov (United States)

    Afanasyev, Valentin; Lobanov, Sergey; Vasiliy, Koptil; Bogdan, Pomazanskiy; Alexander, Gerasimchuk; Nikolay, Pokhilenko

    2010-05-01

    Diamond placers are widespread in the modern alluvial deposits and ancient sedimentary collectors of the Siberian craton and can be divided into two major types: 1) related with the rich and famous kimberlites such as Mir and International pipe and 2) with unidentified root source. The lattert are wide spread, industrially significant and in use in the north-east of the Siberian craton. Yet, kimberlites known in the north-east of the Siberian craton have poor diamond concentrations or non-diamondiferous at all. A contradiction occur between high alluvial and extremely-low host diamond content of this region. Detailed studies of this problem led to the fact that diamonds from the alluvial deposits of the Siberian craton, as well as other diamondiferous regions, show broader spectrum of typomorphic features than diamonds from the known kimberlites. Moreover, some diamond groups are not typical for the phanerozoic kimberlites of Siberia, or do not occur in significant amounts. The foregoing suggests that diamonds from the unknown host rock type occur in the diamond placers of the Siberian craton along with typical kimberlite diamonds. Based on the detailed studies of the typomorphic features of the alluvial diamonds from Siberian craton 5 parasteresis groups, probably related to different host rock types, were distinguished. Parasteresis is a regular spatial mineral association which are united by single geological process, such as kimberlite indicator minerals and diamonds from kimberlites which differ in genesis but united by the whole kimberlitic process. Parasteresis 1 (kimberlite-type) involves diamonds which are common for the phanerozoic kimberlites. Parasteresis 2 (supposed to be lamproitic) includes roundish (cryptolaminar) diamonds of dodecahedron habit, the so called "brazilian" or "ural" types. In Siberian phanerozoic industrial kimberlites the part of such diamonds does not exceed 15%. That is the diamonds which dominate in the placers of the Urals and

  7. High efficiency diamond solar cells

    Science.gov (United States)

    Gruen, Dieter M [Downers Grove, IL

    2008-05-06

    A photovoltaic device and method of making same. A layer of p-doped microcrystalline diamond is deposited on a layer of n-doped ultrananocrystalline diamond such as by providing a substrate in a chamber, providing a first atmosphere containing about 1% by volume CH.sub.4 and about 99% by volume H.sub.2 with dopant quantities of a boron compound, subjecting the atmosphere to microwave energy to deposit a p-doped microcrystalline diamond layer on the substrate, providing a second atmosphere of about 1% by volume CH.sub.4 and about 89% by volume Ar and about 10% by volume N.sub.2, subjecting the second atmosphere to microwave energy to deposit a n-doped ultrananocrystalline diamond layer on the p-doped microcrystalline diamond layer. Electrodes and leads are added to conduct electrical energy when the layers are irradiated.

  8. Lake Erie Water Level Study. Appendix E. Power. Annex D. Computer Programs.

    Science.gov (United States)

    1981-07-01

    1C.2V35965 ,-%:564916?E-O1 .0. 73OS8SE-O2 .-0.3&21 1S6t-O3/ 8____ X=Ig5r.W-900 . IO 10 Oc, I 1 1,6 ArCO .’k 13 ACJPUZ2(..2G.*A .1% RETURN 15 END...QDECIRLEMON,OOI 2 C CALCuLATION OiF DISCHAR6iL FUR OECEV 3 C BA~ItU 014 LAKE [ PIE ELEVA TION ANfl MONTH2 A240 VELLAND CANAL 4 -- -c D IVER SION- 7010D EFS...OMAN REAL _____ ___REFS 93 20162 DEFINED AT 1164 - AtF -- -4 - - 2TIS*0 DEl 10@10 120 Gas 322 0 REAL ARRAY Refs my lab 164 DEFINED 127 ___ 26IF7 05

  9. Transmission diamond imaging detector

    Energy Technology Data Exchange (ETDEWEB)

    Smedley, John, E-mail: smedley@bnl.gov; Pinelli, Don; Gaoweia, Mengjia [Brookhaven National Laboratory, Upton, NY (United States); Muller, Erik; Ding, Wenxiang; Zhou, Tianyi [Stony Brook University, Stony Brook, NY (United States); Bohon, Jen [Case Center for Synchrotron Biosciences, Center for Proteomics and Bioinformatics, Case Western Reserve University, Cleveland, OH (United States)

    2016-07-27

    Many modern synchrotron techniques are trending toward use of high flux beams and/or beams which require enhanced stability and precise understanding of beam position and intensity from the front end of the beamline all the way to the sample. For high flux beams, major challenges include heat load management in optics (including the vacuum windows) and a mechanism of real-time volumetric measurement of beam properties such as flux, position, and morphology. For beam stability in these environments, feedback from such measurements directly to control systems for optical elements or to sample positioning stages would be invaluable. To address these challenges, we are developing diamond-based instrumented vacuum windows with integrated volumetric x-ray intensity, beam profile and beam-position monitoring capabilities. A 50 µm thick single crystal diamond has been lithographically patterned to produce 60 µm pixels, creating a >1kilopixel free-standing transmission imaging detector. This device, coupled with a custom, FPGA-based readout, has been used to image both white and monochromatic x-ray beams and capture the last x-ray photons at the National Synchrotron Light Source (NSLS). This technology will form the basis for the instrumented end-station window of the x-ray footprinting beamline (XFP) at NSLS-II.

  10. Subpicotesla Diamond Magnetometry

    Directory of Open Access Journals (Sweden)

    Thomas Wolf

    2015-10-01

    Full Text Available Nitrogen-vacancy (NV defect centers in diamond are promising solid-state magnetometers. Single centers allow for high-spatial-resolution field imaging but are limited in their magnetic field sensitivity. Using defect-center ensembles, sensitivity can be scaled with sqrt[N] when N is the number of defects. In the present work, we use an ensemble of N∼10^{11} defect centers within an effective sensor volume of 8.5×10^{-4}  mm^{3} for sensing at room temperature. By carefully eliminating noise sources and using high-quality diamonds with large NV concentrations, we demonstrate, for such sensors, a sensitivity scaling as 1/sqrt[t], where t is the total measurement time. The associated photon-shot-noise-limited magnetic-field sensitivity for ac signals of f=20  kHz is 0.9  pT/sqrt[Hz]. For a total measurement time of 100 s, we reach a standard deviation of about 100 fT. Further improvements using decoupling sequences and material optimization could lead to fT/sqrt[Hz] sensitivity.

  11. Diamond Blackfan Syndrome

    Directory of Open Access Journals (Sweden)

    Rahul SINHA, Daljit SINGH, Kirandeep SODHI, Y K KIRAN, Biju JOHN

    2010-01-01

    Full Text Available We report a case of Diamond Blackfan syndrome in 6yr old girl who was detected to have severe anaemia on D4 of life. The baby was detected to have polydactyly right hand (preaxial and weak radial pulse on right side. On examination there was severe pallor without hepatosplenomegaly. The investigations revealed haemoglobin of 1.9 gm% with reticulocyte count of 0.3%. Other investigations were done to establish the cause of anaemia. The sickling test was negative, Peripheral blood smear revealed macrocytic anaemia, Hb electrophoresis revealed fetal haemoglobin of 2.7 %. Bone marrow examination revealed markedly reduced erythroid series, stress cytogenetics study done later was negative for any chromosomal breakage. Based on the clinical profile and investigation reports the diagnosis of Diamond Blackfan Syndrome was made. The child was put on corticosteroids which were gradually tapered. Subsequently any attempt at withdrawl of steroids resulted in fall in haemoglobin levels. Hence the child has been maintained on low dose steroids and has remained symptom free.

  12. 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 ...

  13. CVD diamond metallization and characterization

    Science.gov (United States)

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

    2017-02-01

    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.

  14. 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.

  15. Deep ultraviolet diamond Raman laser.

    Science.gov (United States)

    Granados, Eduardo; Spence, David J; Mildren, Richard P

    2011-05-23

    We present a synchronously pumped diamond Raman laser operating at 275.7 nm pumped by the 4th harmonic of a mode locked Nd:YVO4 laser. The laser had a threshold pump pulse energy of 5.8 nJ and generated up to 0.96 nJ pulses at 10.3% conversion efficiency. The results agree well with a numerical model that includes two-photon absorption of the pump and Stokes beams and uses a Raman gain coefficient of diamond of 100 cm/GW. We also report on the observation of nanometer scale two-photon assisted etching of the diamond crystal surfaces.

  16. Diamond and Diamond-Like Materials as Hydrogen Isotope Barriers

    Energy Technology Data Exchange (ETDEWEB)

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

    1999-07-10

    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.

  17. A Risk Explicit Interval Linear Programming Model for Uncertainty-Based Environmental Economic Optimization in the Lake Fuxian Watershed, China

    Directory of Open Access Journals (Sweden)

    Xiaoling Zhang

    2013-01-01

    Full Text Available The conflict of water environment protection and economic development has brought severe water pollution and restricted the sustainable development in the watershed. A risk explicit interval linear programming (REILP method was used to solve integrated watershed environmental-economic optimization problem. Interval linear programming (ILP and REILP models for uncertainty-based environmental economic optimization at the watershed scale were developed for the management of Lake Fuxian watershed, China. Scenario analysis was introduced into model solution process to ensure the practicality and operability of optimization schemes. Decision makers’ preferences for risk levels can be expressed through inputting different discrete aspiration level values into the REILP model in three periods under two scenarios. Through balancing the optimal system returns and corresponding system risks, decision makers can develop an efficient industrial restructuring scheme based directly on the window of “low risk and high return efficiency” in the trade-off curve. The representative schemes at the turning points of two scenarios were interpreted and compared to identify a preferable planning alternative, which has the relatively low risks and nearly maximum benefits. This study provides new insights and proposes a tool, which was REILP, for decision makers to develop an effectively environmental economic optimization scheme in integrated watershed management.

  18. A risk explicit interval linear programming model for uncertainty-based environmental economic optimization in the Lake Fuxian watershed, China.

    Science.gov (United States)

    Zhang, Xiaoling; Huang, Kai; Zou, Rui; Liu, Yong; Yu, Yajuan

    2013-01-01

    The conflict of water environment protection and economic development has brought severe water pollution and restricted the sustainable development in the watershed. A risk explicit interval linear programming (REILP) method was used to solve integrated watershed environmental-economic optimization problem. Interval linear programming (ILP) and REILP models for uncertainty-based environmental economic optimization at the watershed scale were developed for the management of Lake Fuxian watershed, China. Scenario analysis was introduced into model solution process to ensure the practicality and operability of optimization schemes. Decision makers' preferences for risk levels can be expressed through inputting different discrete aspiration level values into the REILP model in three periods under two scenarios. Through balancing the optimal system returns and corresponding system risks, decision makers can develop an efficient industrial restructuring scheme based directly on the window of "low risk and high return efficiency" in the trade-off curve. The representative schemes at the turning points of two scenarios were interpreted and compared to identify a preferable planning alternative, which has the relatively low risks and nearly maximum benefits. This study provides new insights and proposes a tool, which was REILP, for decision makers to develop an effectively environmental economic optimization scheme in integrated watershed management.

  19. An inexact two-stage stochastic programming model for water resources management in Nansihu Lake Basin, China.

    Science.gov (United States)

    Xie, Y L; Huang, G H; Li, W; Li, J B; Li, Y F

    2013-09-30

    In this study, an inexact two-stage water resources management model was developed for multi-regional water resources planning in the Nansihu lake Basin, China. Four planning districts, four water users, and five water sources were considered in the optimization model, with net system benefit, recourse cost, water supply cost, and wastewater treatment cost being analyzed. Methods of interval-parameter programming (IPP) and two-stage stochastic programming (TSP) were incorporated into the model to tackle uncertainties described by both interval values and probability distributions. A number of scenarios corresponding to different river inflow levels were examined, and the results indicated that different inflow levels could lead to different water allocation schemes with varied system benefit and system-failure risk. In general, the developed model can provide an effective linkage between economic benefits and the associated penalties attributed to the violation of predefined policies. The modeling results were valuable for supporting the adjustment or justification of the existing water allocation schemes within a complicated water resources system under uncertainty. Copyright © 2013 Elsevier Ltd. All rights reserved.

  20. Melanins are Biological Diamonds

    Directory of Open Access Journals (Sweden)

    L. Venger

    2017-06-01

    Full Text Available In the article the physical, chemical, biological properties, the significance and the role in Nature of melanin pigments are considered. Very long time these pigments were considered as metabolism garbage in the living organisms. The comparison of the only same results and facts from the huge masses of the science information with main principles of the new science paradigm – the Theory of Torsion Fields and the Theory of Physical Vacuum – allow to change the view on the true invention, the biological role and the functions of Melanins in Nature. Many theoretical and experimental facts specify on the active participation of melanins in the energyand-informative processes and their first degree role on the all evolution stages of living organisms: from the chemical evolution to the brain and consciousness functions. In the sense Melanins are the most precious substance for the living organisms, true their Diamonds.

  1. Diamond family of nanoparticle superlattices

    Energy Technology Data Exchange (ETDEWEB)

    Liu, W.; Tagawa, M.; Xin, H. L.; Wang, T.; Emamy, H.; Li, H.; Yager, K. G.; Starr, F. W.; Tkachenko, A. V.; Gang, O.

    2016-02-04

    Diamond lattices formed by atomic or colloidal elements exhibit remarkable functional properties. However, building such structures via self-assembly has proven to be challenging because of the low packing fraction, sensitivity to bond orientation, and local heterogeneity. We report a strategy for creating a diamond superlattice of nano-objects via self-assembly and demonstrate its experimental realization by assembling two variant diamond lattices, one with and one without atomic analogs. Our approach relies on the association between anisotropic particles with well-defined tetravalent binding topology and isotropic particles. The constrained packing of triangular binding footprints of truncated tetrahedra on a sphere defines a unique three-dimensional lattice. Hence, the diamond self-assembly problem is solved via its mapping onto two-dimensional triangular packing on the surface of isotropic spherical particles.

  2. Lake Roosevelt Fisheries Monitoring Program; Artificial Imprinting and Smoltification in Juvenile Kokanee Salmon Implications for Operating Lake Roosevelt Kokanee Salmon Hatcheries; 1994 Supplement Report.

    Energy Technology Data Exchange (ETDEWEB)

    Tilson, Mary Beth; Scholz, Allan T.; White, Ronald J. (Eastern Washington University, Upper Columbia United Tribes Fisheries Research Center, Cheney, WA)

    1995-02-01

    At the kokanee salmon hatcheries on Lake Roosevelt, constructed as partial mitigation for effects from Grand Coulee Dam, adult returns have been poor. The reason may be in the imprinting or in the smoltification. A study was initiated in 1992 to determine if there was a critical period for thyroxine induced alfactory imprinting in kokanee salmon; experiments were conducted on imprinting to morpholine and phenethyl alcohol. Other results showed that chemical imprinting coincided with elevated thyroxine levels in 1991 kokanee exposed to synthetic chemicals in 1992. In this report, imprinting experiments were repeated; results showed that imprinting occurred concomitant with elevated thyroxine levels in 1991 kokanee exposed to synthetic chemicals in 1992 and tested in 1994 as age 3 spawners. Imprinting also occurred at the same time as thyroxine peaks in 1992 kokanee exposed to synthetic chemicals in 1993 and tested as age 2 spawners. In both groups fish that had the highest whole body thyroxine content (swimup stage) also had the highest percentage of fish that were attracted to their exposure odor in behavioral tests. So, kokanee salmon imprinted to chemical cues during two sensitive periods during development, at the alevin/swimup and smolt stages. A field test was conducted in Lake Roosevelt on coded wire tagged fish. Smoltification experiments were conducted from 1992 to 1994. Recommendations are made for the Lake Roosevelt kokanee hatcheries.

  3. 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.

  4. "Diamond in the Rough": The Impact of a Remedial Program on College Access and Opportunity for Black Males at an Historically Black Institution

    Science.gov (United States)

    Palmer, Robert T.; Davis, Ryan J.

    2012-01-01

    Researchers, policymakers, and administrations have shown great concern over the efficacy of college remediation, which has prompted some states to eliminate remedial programs from public 4-year institutions. However, research suggests that eliminating these programs may have unintended consequences on college access and opportunity for…

  5. Forest Technology Program, Lake City Community College: The Founding of a School, the Evolution of a College.

    Science.gov (United States)

    Summers, Susan Robinson

    Since 1947, Lake City Community College (LCCC) has evolved from a forest ranger school to a junior college to a true community college. After World War II, Lake City, the "Forestry Capitol of the World," converted a local air base into the Columbia Forestry School (CFS). The first few years were characterized by extremely low enrollment and…

  6. Klamath Basin Restoration Agreement Off-Project Water Program Distance to Perennial Streams and Lakes

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Hydrological Information Products for the Off-Project Water Program of the Klamath Basin Restoration Agreement U.S. Geological Survey Open-File Report 2012-1199 U.S....

  7. Klamath Basin Restoration Agreement Off-Project Water Program Distance to Gaining Streams and Lakes

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Hydrological Information Products for the Off-Project Water Program of the Klamath Basin Restoration Agreement U.S. Geological Survey Open-File Report 2012-1199 U.S....

  8. Lake Roosevelt Fisheries Evaluation Program; Limnological and Fisheries Monitoring, Annual Report 2000.

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Chuck; Scofield, Ben; Pavlik, Deanne

    2003-03-01

    A slightly dryer than normal year yielded flows in Lake Roosevelt that were essentially equal to the past ten year average. Annual mean inflow and outflow were 3,160.3 m3/s and 3,063.4 m3/s respectively. Mean reservoir elevation was 387.2 m above sea level at the Grand Coulee Dam forebay. The forebay elevation was below the mean elevation for a total of 168 days. During the first half of the 2000 forebay elevation changed at a rate of 0.121 m/d and during the last half changed at a rate of 0.208 m/d. The higher rate of elevation change earlier in the year is due to the drawdown to accommodate spring runoff. Mean annual water retention time was 40 days. Annual mean total dissolved gas was 108%. Total dissolved gas was greatest at upriver locations (110% = US/Canada Border annual mean) and decreased moving toward Grand Coulee Dam (106% = Grand Coulee Dam Forebay annual mean). Total dissolved gas was greatest in May (122% reservoir wide monthly mean). Gas bubble trauma was observed in 16 fish primarily largescale suckers and was low in severity. Reservoir wide mean temperatures were greatest in August (19.5 C) and lowest in January (5.5 C). The Spokane River and Sanpoil River Arms experienced higher temperatures than the mainstem reservoir. Brief stratification was observed at the Sanpoil River shore location in July. Warm water temperatures in the Spokane Arm contributed to low dissolved oxygen concentrations in August (2.6 mg/L at 33 m). However, decomposition of summer algal biomass was likely the main cause of depressed dissolved oxygen concentrations. Otherwise, dissolved oxygen profiles were relatively uniform throughout the water column across other sampling locations. Annual mean Secchi depth throughout the reservoir was 5.7 m. Nutrient concentrations were generally low, however, annual mean total phosphorus (0.016 mg/L) was in the mesotrophic range. Annual mean total nitrogen was in the meso-oligotrophic range. Total nitrogen to total phosphorus ratios were

  9. 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

  10. National Program for Inspection of Non-Federal Dams. Lake Waukewan Dam (NH 00306), Merrimack River Basin, Meredith, New Hampshire. Phase I Inspection Report.

    Science.gov (United States)

    1978-10-01

    SAFETY, Merrimack River Basin Meredith New Hampshire Man made outlet between Lake Waukewan and Lake Winnipesaukee 20. ABSTRACT (Contne. en *ere* 80 it...Belknap Town Located: Meredith 5 O Stream: Man made outlet between Lake Waukewan and Lake Winnipesaukee Date of Inspection: June 6, 1978 BRIEF...ASSESSMENT Lake Waukewan Dam is a man-made outlet facility between Lake Waukewan V’ and Lake Winnipesaukee . The facility, a surge and outlet structure has a

  11. 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.

  12. Lake Roosevelt Fisheries Evaluation Program; Assessment of the Lake Roosevelt Walleye Population: Compilation of 1997-1999 Data, 1999-2000 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    McLellan, Jason; McLellan, Holly; Scholz, Allan

    2002-03-01

    A walleye mark-recapture study was conducted on Lake Roosevelt between 1997 and 1999. The primary objective of the study was to describe the status and biological characteristics of the walleye population in Lake Roosevelt by determining its abundance, movement patterns, age structure, growth, condition, and mortality. The abundance estimates were also to be used to estimate the consumptive impact of walleye on stocked kokanee and rainbow trout. Walleye were collected by electrofishing and angling. Each walleye was tagged with an individually numbered Floy tag. The Jolly-Seber model was used to estimate the size of the walleye population in 1999, using each year of the study as a mark-recapture occasion. Mark-recapture data collected in 1998 was re-analyzed in 1999 with the data pooled in various combinations, using closed and open population models, in an attempt to provide an estimate of walleye abundance that was unbiased, accurate, and more precise. Minimum distances traveled between mark and recapture location by tagged walleye were determined from tag returns. Over the three study years, a total of 12,343 walleye {ge} 150 mm TL were collected by Eastern Washington University (EWU), Spokane Tribe of Indians, and Washington Department of Fish and Wildlife, and of those, 10,770 were tagged and released. Of the 10,770 walleye marked and released, 775 were recaptured and returned to EWU. The 1999 abundance estimate ({+-} standard error) for walleye {ge} 150 mm TL was 129,183 ({+-} 45,578) and the estimated abundance ({+-} standard error) of walleye {ge} 200 mm TL was 101,508 ({+-} 35,603). A total of 38 population estimates were calculated for 1998. The estimates of the abundance of walleye {ge} 150 mm TL in Lake Roosevelt ranged from 84,335 to 180,568 fish. Estimates of the size of the walleye population {ge} 200 mm TL ranged from 14,971 to 173,702. The 1999 estimate, which used each study year as a mark-recapture occasion, was biased due to unequal capture

  13. Diamond Films for Implantable Electrodes

    Directory of Open Access Journals (Sweden)

    Petra Henychová

    2012-01-01

    Full Text Available Diamond is a promising material for implantable electrodes due to its unique properties. The aim of this work is to investigate the growth of boron-doped nanocrystalline diamond (B-NCD films by plasma-enhanced microwave chemical vapor deposition at various temperatures, and to propose optimal diamond growth conditions for implantable electrodes. We have investigated the temperature dependence (450 °C–820 °C of boron incorporation, surface morphology and growth rate on a polished quartz plate. Surface morphology and thickness were examined by atomic force microscopy (AFM.The quality of the films in terms of diamond and non-diamond phase of carbon was investigated by Raman spectroscopy. AFM imaging showed that the size of the grains was determined mainly by the thickness of the films, and varied from an average size of 40 nm in the lowest temperature sample to an average size of 150 nm in the sample prepared at the highest temperature. The surface roughness of the measured samples varied between 10 (495 °C and 25 nm (800 °C. The growth rate of the sample increased with temperature. We found that the level of boron doping was strongly dependent on temperature during deposition. An optimal B-NCD sample was prepared at 595 °C.

  14. Nanocrystalline diamond synthesized from C60

    Energy Technology Data Exchange (ETDEWEB)

    Dubrovinskaia, N.; Dubrovinsky, L.; Langehorst, F.; Jacobsen, S.; Liebske, C. (Bayreuth)

    2010-11-30

    A bulk sample of nanocrystalline cubic diamond with crystallite sizes of 5-12 nm was synthesized from fullerene C{sub 60} at 20(1) GPa and 2000 C using a multi-anvil apparatus. The new material is at least as hard as single crystal diamond. It was found that nanocrystalline diamond at high temperature and ambient pressure kinetically is more stable with respect to graphitization than usual diamonds.

  15. Coral Research Data from NOAA's Undersea Research Center, North Atlantic and Great Lakes Region, NOAA's Undersea Research Program (NURP)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA's Undersea Research Center for the NOAA's Undersea Research Center for the North Atlantic and Great Lakes region (NAGL) explores and studies the waters off the...

  16. 2008 US Army Corps of Engineers (USACE) National Coastal Mapping Program (NCMP) Topobathy Lidar - Illinois (Lake Michigan shoreline)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The data contained in these files contain hydrographic and topographic data collected by the CHARTS system along the Lake Michigan coast of Illinois from September...

  17. 2007 US Army Corps of Engineers (USACE) National Coastal Mapping Program (NCMP) Topobathy Lidar - Michigan (Lake Huron shoreline)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This is a bare earth data set. The data contained in these files contain hydrographic and topographic data collected by the CHARTS system along the Lake Huron coast...

  18. 2008 US Army Corps of Engineers (USACE) National Coastal Mapping Program (NCMP) Topobathy Lidar - Indiana (Lake Michigan shoreline)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The data contained in these files contain topographic data collected by the CHARTS system along Lake Michigan, Indiana. The data are broken into boxes. The box...

  19. Ultratough single crystal boron-doped diamond

    Science.gov (United States)

    Hemley, Russell J [Carnegie Inst. for Science, Washington, DC ; Mao, Ho-Kwang [Carnegie Inst. for Science, Washington, DC ; Yan, Chih-Shiue [Carnegie Inst. for Science, Washington, DC ; Liang, Qi [Carnegie Inst. for Science, Washington, DC

    2015-05-05

    The invention relates to a single crystal boron doped CVD diamond that has a toughness of at least about 22 MPa m.sup.1/2. The invention further relates to a method of manufacturing single crystal boron doped CVD diamond. The growth rate of the diamond can be from about 20-100 .mu.m/h.

  20. Diamonds at the golden point

    CERN Document Server

    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...

  1. Diamond Quantum Devices in Biology.

    Science.gov (United States)

    Wu, Yuzhou; Jelezko, Fedor; Plenio, Martin B; Weil, Tanja

    2016-06-01

    The currently available techniques for molecular imaging capable of reaching atomic resolution are limited to low temperatures, vacuum conditions, or large amounts of sample. Quantum sensors based on the spin-dependent photoluminescence of nitrogen-vacancy (NV) centers in diamond offer great potential to achieve single-molecule detection with atomic resolution under ambient conditions. Diamond nanoparticles could also be prepared with implanted NV centers, thereby generating unique nanosensors that are able to traffic into living biological systems. Therefore, this technique might provide unprecedented access and insight into the structure and function of individual biomolecules under physiological conditions as well as observation of biological processes down to the quantum level with atomic resolution. The theory of diamond quantum sensors and the current developments from their preparation to sensing techniques have been critically discussed in this Minireview. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. The diamond nano-balance.

    Science.gov (United States)

    Williams, Oliver A; Mortet, Vincent; Daenen, Michael; Haenen, Ken

    2009-06-01

    Detecting nano-gram quantities of analyte in the liquid or gas phase is crucial for pathogen detection, antigen/DNA detection, water monitoring, electrochemical analysis, and many other bio-electrochemical applications. The quartz crystal microbalance (QCM) has become a significant sensor for both liquid and gas phase graviometry due to its high sensitivity, robustness, ease of use and simultaneous electrochemistry capabilities. One key factor plaguing the QCM in most sensor applications is the stability of the surface functionalisation. Diamond offers the most stable surface for functionalisation, the widest electrochemical window and the lowest noise floor. Unfortunately the growth of diamond on QCMs is problematic due to the low curie point of quartz, resulting in the loss of the piezoelectric properties of the QCM. In this work the replacement of the quartz with a high temperature stable piezoelectric material is proposed, and a nanocrystalline diamond coated sensor demonstrated.

  3. 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.

  4. Surface temperature measurements of diamond

    CSIR Research Space (South Africa)

    Masina, BN

    2006-07-01

    Full Text Available - ing session. REFERENCES 1. W. L. Heinz, Diamond drilling handbook, CHP2, 27-47. 2. Max N. Yoder, Diamond properties and applications, 1-18, Noyes publications, edited by Robert F. Davis. 3. Kogelnik and Li, Laser beams and resonators, 1966.... Stephen, Laser heating dia- mond cell system at the advanced photon source for in situ x-ray measurements at high at pressure and temperature, 2000, Vol 72, 1273- 1282. 6. D.L. Heinz, J.S. Sweeney and P. Miller, A laser heating system that stabilizes...

  5. Optically transparent composite diamond/Ti electrodes

    Czech Academy of Sciences Publication Activity Database

    Ashcheulov, Petr; Taylor, Andrew; More Chevalier, Joris; Kovalenko, A.; Remeš, Zdeněk; Drahokoupil, Jan; Hubík, Pavel; Fekete, Ladislav; Klimša, Ladislav; Kopeček, Jaromír; Remiášová, Jarmila; Kohout, Michal; Frank, Otakar; Kavan, Ladislav; Mortet, Vincent

    2017-01-01

    Roč. 119, Aug (2017), s. 179-189 ISSN 0008-6223 R&D Projects: GA MŠk LO1409; GA MŠk LM2015088; GA ČR GA13-31783S Grant - others:FUNBIO(XE) CZ.2.16/3.1.00/21568; AV ČR(CZ) Fellowship J. E. Purkyně; AV ČR(CZ) MSM100101602 Program:Program na podporu mezinárodní spolupráce začínajících výzkumných pracovníků Institutional support: RVO:68378271 ; RVO:61388955 Keywords : diamond * transparent film * composite electrode * conductive thin film Subject RIV: BM - Solid Matter Physics ; Magnetism; CF - Physical ; Theoretical Chemistry (UFCH-W) OBOR OECD: Condensed matter physics (including formerly solid state physics, supercond.); Physical chemistry (UFCH-W) Impact factor: 6.337, year: 2016

  6. Sanctuaries for lake trout in the Great Lakes

    Science.gov (United States)

    Stanley, Jon G.; Eshenroder, Randy L.; Hartman, Wilbur L.

    1987-01-01

    Populations of lake trout, severely depleted in Lake Superior and virtually extirpated from the other Great Lakes because of sea lamprey predation and intense fishing, are now maintained by annual plantings of hatchery-reared fish in Lakes Michigan, Huron, and Ontario and parts of Lake Superior. The extensive coastal areas of the Great Lakes and proximity to large populations resulted in fishing pressure on planted lake trout heavy enough to push annual mortality associated with sport and commercial fisheries well above the critical level needed to reestablish self-sustaining stocks. The interagency, international program for rehabilitating lake trout includes controlling sea lamprey abundance, stocking hatchery-reared lake trout, managing the catch, and establishing sanctuaries where harvest is prohibited. Three lake trout sanctuaries have been established in Lake Michigan: the Fox Island Sanctuary of 121, 500 ha, in the Chippewa-Ottawa Treaty fishing zone in the northern region of the lake; the Milwaukee Reef Sanctuary of 160, 000 ha in midlake, in boundary waters of Michigan and Wisconsin; and Julian's Reef Sanctuary of 6, 500 ha, in Illinois waters. In northern Lake Huron, Drummond Island Sanctuary of 55, 000 ha is two thirds in Indian treaty-ceded waters in Michigan and one third in Ontario waters of Canada. A second sanctuary, Six Fathom Bank-Yankee Reef Sanctuary, in central Lake Huron contains 168, 000 ha. Sanctuary status for the Canadian areas remains to be approved by the Provincial government. In Lake Superior, sanctuaries protect the spawning grounds of Gull Island Shoal (70, 000 ha) and Devils Island Shoal (44, 000 ha) in Wisconsin's Apostle Island area. These seven sanctuaries, established by the several States and agreed upon by the States, Indian tribes, the U.S. Department of the Interior, and the Province of Ontario, contribute toward solving an interjurisdictional fishery problem.

  7. Method for machining steel with diamond tools

    Science.gov (United States)

    Casstevens, J.M.

    1984-01-01

    The present invention is directed to a method for machine optical quality finishes and contour accuracies of workpieces of carbon-containing metals such as steel with diamond tooling. The wear rate of the diamond tooling is significantly reduced by saturating the atmosphere at the interface of the workpiece and the diamond tool with a gaseous hydrocarbon during the machining operation. The presence of the gaseous hydrocarbon effectively eliminates the deterioration of the diamond tool by inhibiting or preventing the conversion of the diamond carbon to graphite carbon at the point of contact between the cutting tool and the workpiece.

  8. CVD diamond for electronic devices and sensors

    CERN Document Server

    2009-01-01

    Synthetic diamond is diamond produced by using chemical or physical processes. Like naturally occurring diamond it is composed of a three-dimensional carbon crystal. Due to its extreme physical properties, synthetic diamond is used in many industrial applications, such as drill bits and scratch-proof coatings, and has the potential to be used in many new application areas A brand new title from the respected Wiley Materials for Electronic and Optoelectronic Applications series, this title is the most up-to-date resource for diamond specialists. Beginning with an introduction to the pr

  9. 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.

  10. Diamond Ablators for Inertial Confinement Fusion

    Energy Technology Data Exchange (ETDEWEB)

    Biener, J; Mirkarimi, P B; Tringe, J W; Baker, S L; Wang, Y M; Kucheyev, S O; Teslich, N E; Wu, K J; Hamza, A V; Wild, C; Woerner, E; Koidl, P; Bruehne, K; Fecht, H

    2005-06-21

    Diamond has a unique combination of physical properties for the inertial confinement fusion ablator application, such as appropriate optical properties, high atomic density, high yield strength, and high thermal conductivity. Here, we present a feasible concept to fabricate diamond ablator shells. The fabrication of diamond capsules is a multi-step process, which involves diamond chemical vapor deposition on silicon mandrels followed by polishing, microfabrication of holes, and removing of the silicon mandrel by an etch process. We also discuss the pros and cons of coarse-grained optical quality and nanocrystalline chemical vapor deposition diamond films for the ablator application.

  11. Investigation of Applications of Diamond Film

    Science.gov (United States)

    1989-11-01

    CN /H2 Figure 10. Schematic-of DQ dlscharge CVD diamond aRoaratu. D C MICROWAVE SUBSTRATE 7UBSTRATE / GAS GAS INLET INLET REACTOR MICROWAVE EI1A~G EN...Diamond films were synthesized using a DC plasma-enhanced chemical vapor deposition reactor developed for diamond deposition. Deposition protocol was a...a 10-fold increase in the life of steel bearings. 111 NORMALIZED RESISTANCE TO WEAR CHROMIUM == 1.0, EXTRAP TO DIAMOND Diamond 7- 6 7F z (1) 7 U N 3

  12. Transparent nanocrystalline diamond coatings and devices

    Energy Technology Data Exchange (ETDEWEB)

    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.

  13. Microinclusions in polycrystalline diamonds: insights into processes of diamond formation

    Science.gov (United States)

    Jacob, D. E.; Wirth, R.; Enzmann, F.; Schwarz, J. O.; Kronz, A.

    2009-04-01

    Polycrystalline diamond aggregates (framesites) contain silicates of eclogitic and peridotitic affinity (e.g. Kurat and Dobosi, 2000). The minerals occur mostly in interstices and are intimately intergrown with the diamonds, indicating contemporaneous crystallization within the diamond stability field in the Earth's mantle. In addition to silicates, rarer phases such as Fe-carbide can sometimes be found in framesites that record unusually low local oxygen fugacity at the time of their formation (Jacob et al., 2004). Furthermore, while most gem-sized diamonds have old, often Archaean formation ages, some polycrystalline diamond aggregates have been shown to form directly preceding the kimberlite eruption (Jacob et al., 2000). Thus, these samples may provide a unique source of information on the nature and timing of small scale processes that lead to diamond formation and complement evidence from gem-sized diamonds. Here, we present a study of micro- and nano-inclusions in diamonds from a polycrystalline diamond aggregate (framesite) from the Orapa Mine (Botswana) and combine results from TEM/FIB analyses with high-resolution computerized micro-tomography (HR-µCT) and electron microprobe analyses to further constrain the formation of diamond in the Earth's mantle. Results In total, 14 microinclusions from fifteen FIB foils were investigated. Micro- and nano-inclusions identified by TEM were smaller than 1µm down to ca. 50nm in size, and are both monomineralic and multi-phase. The cavities are often lath-shaped and oriented parallel to each other; many show lattice dislocations in the surrounding diamond. In addition, inclusions are found along open cracks within the diamond single crystals. Mineral phases in the microinclusions comprise rutile, omphacite and a FeS phase (pyrrhotite). The multiphase inclusions most often consist of cavities that are only partly occupied (less than 50% of the total space), suggesting that the empty space was originally filled by a

  14. Microplasma device architectures with various diamond nanostructures

    Science.gov (United States)

    Kunuku, Srinivasu; Jothiramalingam Sankaran, Kamatchi; Leou, Keh-Chyang; Lin, I.-Nan

    2017-02-01

    Diamond nanostructures (DNSs) were fabricated from three different morphological diamonds, microcrystalline diamond (MCD), nanocrystalline diamond (NCD), and ultrananocrystalline diamond (UNCD) films, using a reactive ion etching method. The plasma illumination (PI) behavior of microplasma devices using the DNSs and the diamond films as cathode were investigated. The Paschen curve approach revealed that the secondary electron emission coefficient (γ value) of diamond materials is similar irrespective of the microstructure (MCD, NCD, and UNCD) and geometry of the materials (DNSs and diamond films). The diamond materials show markedly larger γ-coefficient than conventional metallic cathode materials such as Mo that resulted in markedly better PI behavior for the corresponding microplasma devices. Moreover, the PI behavior, i.e. the voltage dependence of plasma current density (J pl-V), plasma density (n e-V), and the robustness of the devices, varied markedly with the microstructure and geometry of the cathode materials that was closely correlated to the electron field emission (EFE) properties of the cathode materials. The UNCD nanopillars, possessing good EFE properties, resulted in superior PI behavior, whereas the MCD diamond films with insufficient EFE properties led to inferior PI behavior. Consequently, enhancement of plasma characteristics is the collective effects of EFE behavior and secondary electron emission characteristics of diamond-based cathode materials.

  15. Entanglement, holography and causal diamonds

    NARCIS (Netherlands)

    de Boer, J.; Haehl, F.M.; Heller, M.P.; Myers, R.C.

    We argue that the degrees of freedom in a d-dimensional CFT can be reorganized in an insightful way by studying observables on the moduli space of causal diamonds (or equivalently, the space of pairs of timelike separated points). This 2d-dimensional space naturally captures some of the fundamental

  16. Assessment of water quality in Ahor Lake - Ghana

    African Journals Online (AJOL)

    user

    water demand during dry seasons. After the collapse of. Ghana Consolidated Diamonds which took over operations from the CAST mining company, the Dam has been abandoned. Recently, the Municipal has taken interest in the water body to develop it for recreational purpose. Climatically, Lake Ahor lies within the Wet ...

  17. Diamond-modified AFM probes: from diamond nanowires to atomic force microscopy-integrated boron-doped diamond electrodes.

    Science.gov (United States)

    Smirnov, Waldemar; Kriele, Armin; Hoffmann, René; Sillero, Eugenio; Hees, Jakob; Williams, Oliver A; Yang, Nianjun; Kranz, Christine; Nebel, Christoph E

    2011-06-15

    In atomic force microscopy (AFM), sharp and wear-resistant tips are a critical issue. Regarding scanning electrochemical microscopy (SECM), electrodes are required to be mechanically and chemically stable. Diamond is the perfect candidate for both AFM probes as well as for electrode materials if doped, due to diamond's unrivaled mechanical, chemical, and electrochemical properties. In this study, standard AFM tips were overgrown with typically 300 nm thick nanocrystalline diamond (NCD) layers and modified to obtain ultra sharp diamond nanowire-based AFM probes and probes that were used for combined AFM-SECM measurements based on integrated boron-doped conductive diamond electrodes. Analysis of the resonance properties of the diamond overgrown AFM cantilevers showed increasing resonance frequencies with increasing diamond coating thicknesses (i.e., from 160 to 260 kHz). The measured data were compared to performed simulations and show excellent correlation. A strong enhancement of the quality factor upon overgrowth was also observed (120 to 710). AFM tips with integrated diamond nanowires are shown to have apex radii as small as 5 nm and where fabricated by selectively etching diamond in a plasma etching process using self-organized metal nanomasks. These scanning tips showed superior imaging performance as compared to standard Si-tips or commercially available diamond-coated tips. The high imaging resolution and low tip wear are demonstrated using tapping and contact mode AFM measurements by imaging ultra hard substrates and DNA. Furthermore, AFM probes were coated with conductive boron-doped and insulating diamond layers to achieve bifunctional AFM-SECM probes. For this, focused ion beam (FIB) technology was used to expose the boron-doped diamond as a recessed electrode near the apex of the scanning tip. Such a modified probe was used to perform proof-of-concept AFM-SECM measurements. The results show that high-quality diamond probes can be fabricated, which are

  18. Lake Cadagno

    DEFF Research Database (Denmark)

    Tonolla, Mauro; Storelli, Nicola; Danza, Francesco

    2017-01-01

    Lake Cadagno (26 ha) is a crenogenic meromictic lake located in the Swiss Alps at 1921 m asl with a maximum depth of 21 m. The presence of crystalline rocks and a dolomite vein rich in gypsum in the catchment area makes the lake a typical “sulphuretum ” dominated by coupled carbon and sulphur cyc...

  19. Nitrogen and hydrogen related infrared absorption in CVD diamond films

    Energy Technology Data Exchange (ETDEWEB)

    Titus, E. [Department of Mechanical Engineering, University of Aveiro, 3810-193 (Portugal)]. E-mail: elby@mec.ua.pt; Ali, N. [Department of Mechanical Engineering, University of Aveiro, 3810-193 (Portugal); Cabral, G. [Department of Mechanical Engineering, University of Aveiro, 3810-193 (Portugal); Madaleno, J.C. [Department of Mechanical Engineering, University of Aveiro, 3810-193 (Portugal); Neto, V.F. [Department of Mechanical Engineering, University of Aveiro, 3810-193 (Portugal); Gracio, J. [Department of Mechanical Engineering, University of Aveiro, 3810-193 (Portugal); Ramesh Babu, P [Materials Ireland, Polymer research Centre, School of Physics, Dublin (Ireland); Sikder, A.K. [Department of Physics, Indian Institute of Technology (IIT), Bombay (India); Okpalugo, T.I. [Northern Ireland Bio-Engineering Centre, NIBEC, University of Ulster (United Kingdom); Misra, D.S. [Department of Physics, Indian Institute of Technology (IIT), Bombay (India)

    2006-09-25

    In this paper, we investigate on the presence of hydrogen and nitrogen related infrared absorptions in chemical vapour deposited (CVD) diamond films. Investigations were carried out in cross sections of diamond windows, deposited using hot filament CVD (HFCVD). The results of Scanning Electron Microscopy (SEM), Fourier Transform Infrared (FTIR) and Raman spectroscopy carried out in a cross section of self-standing diamond sheets are presented. The FTIR spectra showed several features that have not been reported before. In order to confirm the frequency of nitrogen related vibrations, ab-initio calculations were carried out using GAMESS program. The investigations showed the presence of several C-N related peaks in one-phonon (1000-1333 cm{sup -1}). The deconvolution of the spectra in the three-phonon region (2700-3150 cm{sup -1}) also showed a number of vibration modes corresponding to sp {sup m}CH {sub n} phase of carbon. Elastic recoil detection analysis (ERDA) was employed to compare the H content measured using FTIR technique. Using these measurements we point out that the oscillator strength of the different IR modes varies depending upon the structure and H content of CVD diamond sheets.

  20. LIMNOLOGY, LAKE BASINS, LAKE WATERS

    Directory of Open Access Journals (Sweden)

    Petre GÂŞTESCU

    2009-06-01

    Full Text Available Limnology is a border discipline between geography, hydrology and biology, and is also closely connected with other sciences, from it borrows research methods. Physical limnology (the geography of lakes, studies lake biotopes, and biological limnology (the biology of lakes, studies lake biocoenoses. The father of limnology is the Swiss scientist F.A. Forel, the author of a three-volume entitled Le Leman: monographie limnologique (1892-1904, which focuses on the geology physics, chemistry and biology of lakes. He was also author of the first textbook of limnology, Handbuch der Seenkunde: allgemeine Limnologie,(1901. Since both the lake biotope and its biohydrocoenosis make up a single whole, the lake and lakes, respectively, represent the most typical systems in nature. They could be called limnosystems (lacustrine ecosystems, a microcosm in itself, as the American biologist St.A. Forbes put it (1887.

  1. Lake Roosevelt Fisheries Evaluation Program, Part C; Lake Roosevelt Pelagic Fish Study: Washington Department of Fish and Wildlife, 1998 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Baldwin, Casey; Polacek, Matt; Bonar, Scott

    2002-11-01

    Pelagic fishes, such as kokanee and rainbow trout, provide an important fishery in Lake Roosevelt; however, spawner returns and creel results have been below management goals in recent years. Our objective was to identify factors that potentially limit pelagic fish production in Lake Roosevelt including entrainment, food limitation, piscivory, and other abiotic factors. We estimated the ratio of total fish entrained through Grand Coulee Dam to the pelagic fish abundance for September and October, 1998. If the majority of these fish were pelagic species, then entrainment averaged 10-13% of pelagic fish abundance each month. This rate of entrainment could impose considerable losses to pelagic fish populations on an annual basis. Therefore, estimates of species composition of entrained fish will be important in upcoming years to estimate the proportion of stocked pelagic fish lost through the dam. Food was not limiting for kokanee or rainbow trout populations since growth rates were high and large zooplankton were present in the reservoir. Estimates of survival for kokanee were low (< 0.01 annual) and unknown for rainbow trout. We estimated that the 1997 standing stock biomass of large (>1.1 mm) Daphnia could have supported 0.08 annual survival by kokanee and rainbow trout before fish consumption would have exceeded available biomass during late winter and early spring. Therefore, if recruitment goals are met in the future there may be a bottleneck in food supply for pelagic planktivores. Walleye and northern pikeminnow were the primary piscivores of salmonids in 1996 and 1997. Predation on salmonid prey was rare for rainbow trout and not detected for burbot or smallmouth bass. Northern pikeminnow had the greatest individual potential as a salmonid predator due to their high consumptive demand; however, their overall impact was limited because of their low relative abundance. We modeled the predation impact of 273,524 walleye in 1996, and 39,075 northern pikeminnow in

  2. Family forest landowners' interest in forest carbon offset programs: Focus group findings from the Lake States, USA

    Science.gov (United States)

    Kristell A. Miller; Stephanie A. Snyder; Mike A. Kilgore; Mae A. Davenport

    2014-01-01

    In 2012, focus groups were organized with individuals owning 20+ acres in the Lake States region of the United States (Michigan, Minnesota, and Wisconsin) to discuss various issues related to forest carbon offsetting. Focus group participants consisted of landowners who had responded to an earlier mail-back survey (2010) on forest carbon offsets. Two focus groups were...

  3. Evaluation of Sugar Maple Dieback in the Upper Great Lakes Region and Development of a Forest Health Youth Education Program

    Science.gov (United States)

    Bal, Tara L.

    2013-01-01

    Sugar Maple, "Acer saccharum" Marsh., is one of the most valuable trees in the northern hardwood forests. Severe dieback was recently reported by area foresters in the western Upper Great Lakes Region. Sugar Maple has had a history of dieback over the last 100 years throughout its range and different variables have been identified as…

  4. 33 CFR 110.6 - Portland Harbor, Portland, Maine (between Little Diamond Island and Great Diamond Island).

    Science.gov (United States)

    2010-07-01

    ... (between Little Diamond Island and Great Diamond Island). 110.6 Section 110.6 Navigation and Navigable... Areas § 110.6 Portland Harbor, Portland, Maine (between Little Diamond Island and Great Diamond Island). Beginning at the southeasterly corner of the wharf, at the most southerly point of Great Diamond Island at...

  5. Ultrananocrystalline diamond contacts for electronic devices

    Energy Technology Data Exchange (ETDEWEB)

    Sumant, Anirudha V.; Smedley, John; Muller, Erik

    2017-12-12

    A method of forming electrical contacts on a diamond substrate comprises producing a plasma ball using a microwave plasma source in the presence of a mixture of gases. The mixture of gases include a source of a p-type or an n-type dopant. The plasma ball is disposed at a first distance from the diamond substrate. The diamond substrate is maintained at a first temperature. The plasma ball is maintained at the first distance from the diamond substrate for a first time, and a UNCD film, which is doped with at least one of a p-type dopant and an n-type dopant, is disposed on the diamond substrate. The doped UNCD film is patterned to define UNCD electrical contacts on the diamond substrate.

  6. Microhabitat use of the diamond darter

    Science.gov (United States)

    Welsh, Stuart A.; Smith, Dustin M.; Taylor, Nate D.

    2013-01-01

    The only known extant population of the diamond darter (Crystallaria cincotta) exists in the lower 37 km of Elk River, WV, USA. Our understanding of diamond darter habitat use was previously limited, because few individuals have been observed during sampling with conventional gears. We quantified microhabitat use of diamond darters based on measurements of water depth, water velocity and per cent substrate composition. Using spotlights at night-time, we sampled 16 sites within the lower 133 km of Elk River and observed a total of 82 diamond darters at 10 of 11 sampling sites within the lower 37 km. Glides, located immediately upstream of riffles, were the primary habitats sampled for diamond darters, which included relatively shallow depths (habitats within Elk River. Spotlighting, a successful sampling method for diamond darters, should be considered for study designs of population estimation and long-term monitoring.

  7. Diamond turning machine controller implementation

    Energy Technology Data Exchange (ETDEWEB)

    Garrard, K.P.; Taylor, L.W.; Knight, B.F.; Fornaro, R.J.

    1988-12-01

    The standard controller for a Pnuemo ASG 2500 Diamond Turning Machine, an Allen Bradley 8200, has been replaced with a custom high-performance design. This controller consists of four major components. Axis position feedback information is provided by a Zygo Axiom 2/20 laser interferometer with 0.1 micro-inch resolution. Hardware interface logic couples the computers digital and analog I/O channels to the diamond turning machine`s analog motor controllers, the laser interferometer, and other machine status and control information. It also provides front panel switches for operator override of the computer controller and implement the emergency stop sequence. The remaining two components, the control computer hardware and software, are discussed in detail below.

  8. The Volume of Earth's Lakes

    Science.gov (United States)

    Cael, B. B.

    How much water do lakes on Earth hold? Global lake volume estimates are scarce, highly variable, and poorly documented. We develop a mechanistic null model for estimating global lake mean depth and volume based on a statistical topographic approach to Earth's surface. The volume-area scaling prediction is accurate and consistent within and across lake datasets spanning diverse regions. We applied these relationships to a global lake area census to estimate global lake volume and depth. The volume of Earth's lakes is 199,000 km3 (95% confidence interval 196,000-202,000 km3) . This volume is in the range of historical estimates (166,000-280,000 km3) , but the overall mean depth of 41.8 m (95% CI 41.2-42.4 m) is significantly lower than previous estimates (62 - 151 m). These results highlight and constrain the relative scarcity of lake waters in the hydrosphere and have implications for the role of lakes in global biogeochemical cycles. We also evaluate the size (area) distribution of lakes on Earth compared to expectations from percolation theory. This material is based upon work supported by the National Science Foundation Graduate Research Fellowship Program under Grant No. 2388357.

  9. Developing Energy Technology Course for Undergraduate Engineering Management Study Program in Lake Toba Area with Particular Focus to Sustainable Energy Systems in Development Context

    Science.gov (United States)

    Manik, Yosef; Sinaga, Rizal; Saragi, Hadi

    2018-02-01

    Undergraduate Engineering Management Study Program of Institut Teknologi Del is one of the pioneers for its field in Indonesia. Located in Lake Toba Area, this study program has a mission to provide high quality Engineering Management education that produces globally competitive graduates who in turn will contribute to local development. Framing the Energy Technology course—one of the core subjects in Engineering Management Body of Knowledge—in the context of sustainable development of Lake Toba Area is very essential. Thus, one particular focus in this course is sustainable energy systems in local development context that incorporates identification and analysis of locally available energy resources. In this paper we present our experience in designing such course. In this work, we introduce the domains that shape the Engineering Management Body of Knowledge. Then, we explain the results of our evaluation on the key considerations to meet the rapidly changing needs of society in local context. Later, we present the framework of the learning outcomes and the syllabus as a result of mapping the road map with the requirement. At the end, the summary from the first two semesters of delivering this course in academic year 2015/2016 and 2016/2017 are reported.

  10. Diamond turning of thermoplastic polymers

    Energy Technology Data Exchange (ETDEWEB)

    Smith, E.; Scattergood, R.O.

    1988-12-01

    Single point diamond turning studies were made using a series of thermoplastic polymers with different glass transition temperatures. Variations in surface morphology and surface roughness were observed as a function of cutting speed. Lower glass transition temperatures facilitate smoother surface cuts and better surface finish. This can be attributed to the frictional heating that occurs during machining. Because of the very low glass transition temperatures in polymeric compared to inorganic glasses, the precision machining response can be very speed sensitive.

  11. Thermal Conductivity of Diamond Composites

    Science.gov (United States)

    Kidalov, Sergey V.; Shakhov, Fedor M.

    2009-01-01

    A major problem challenging specialists in present-day materials sciences is the development of compact, cheap to fabricate heat sinks for electronic devices, primarily for computer processors, semiconductor lasers, high-power microchips, and electronics components. The materials currently used for heat sinks of such devices are aluminum and copper, with thermal conductivities of about 250 W/(m·K) and 400 W/(m·K), respectively. Significantly, the thermal expansion coefficient of metals differs markedly from those of the materials employed in semiconductor electronics (mostly silicon); one should add here the low electrical resistivity metals possess. By contrast, natural single-crystal diamond is known to feature the highest thermal conductivity of all the bulk materials studied thus far, as high as 2,200 W/(m·K). Needless to say, it cannot be applied in heat removal technology because of high cost. Recently, SiC- and AlN-based ceramics have started enjoying wide use as heat sink materials; the thermal conductivity of such composites, however, is inferior to that of metals by nearly a factor two. This prompts a challenging scientific problem to develop diamond-based composites with thermal characteristics superior to those of aluminum and copper, adjustable thermal expansion coefficient, low electrical conductivity and a moderate cost, below that of the natural single-crystal diamond. The present review addresses this problem and appraises the results reached by now in studying the possibility of developing composites in diamond-containing systems with a view of obtaining materials with a high thermal conductivity.

  12. Thermal Conductivity of Diamond Composites

    Directory of Open Access Journals (Sweden)

    Fedor M. Shakhov

    2009-12-01

    Full Text Available A major problem challenging specialists in present-day materials sciences is the development of compact, cheap to fabricate heat sinks for electronic devices, primarily for computer processors, semiconductor lasers, high-power microchips, and electronics components. The materials currently used for heat sinks of such devices are aluminum and copper, with thermal conductivities of about 250 W/(m·K and 400 W/(m·K, respectively. Significantly, the thermal expansion coefficient of metals differs markedly from those of the materials employed in semiconductor electronics (mostly silicon; one should add here the low electrical resistivity metals possess. By contrast, natural single-crystal diamond is known to feature the highest thermal conductivity of all the bulk materials studied thus far, as high as 2,200 W/(m·K. Needless to say, it cannot be applied in heat removal technology because of high cost. Recently, SiC- and AlN-based ceramics have started enjoying wide use as heat sink materials; the thermal conductivity of such composites, however, is inferior to that of metals by nearly a factor two. This prompts a challenging scientific problem to develop diamond-based composites with thermal characteristics superior to those of aluminum and copper, adjustable thermal expansion coefficient, low electrical conductivity and a moderate cost, below that of the natural single-crystal diamond. The present review addresses this problem and appraises the results reached by now in studying the possibility of developing composites in diamond-containing systems with a view of obtaining materials with a high thermal conductivity.

  13. Entanglement, holography and causal diamonds

    Energy Technology Data Exchange (ETDEWEB)

    Boer, Jan de [Institute of Physics, Universiteit van Amsterdam,Science Park 904, 1090 GL Amsterdam (Netherlands); Haehl, Felix M. [Centre for Particle Theory & Department of Mathematical Sciences, Durham University,South Road, Durham DH1 3LE (United Kingdom); Heller, Michal P.; Myers, Robert C. [Perimeter Institute for Theoretical Physics,31 Caroline Street North, Waterloo, Ontario N2L 2Y5 (Canada)

    2016-08-29

    We argue that the degrees of freedom in a d-dimensional CFT can be re-organized in an insightful way by studying observables on the moduli space of causal diamonds (or equivalently, the space of pairs of timelike separated points). This 2d-dimensional space naturally captures some of the fundamental nonlocality and causal structure inherent in the entanglement of CFT states. For any primary CFT operator, we construct an observable on this space, which is defined by smearing the associated one-point function over causal diamonds. Known examples of such quantities are the entanglement entropy of vacuum excitations and its higher spin generalizations. We show that in holographic CFTs, these observables are given by suitably defined integrals of dual bulk fields over the corresponding Ryu-Takayanagi minimal surfaces. Furthermore, we explain connections to the operator product expansion and the first law of entanglement entropy from this unifying point of view. We demonstrate that for small perturbations of the vacuum, our observables obey linear two-derivative equations of motion on the space of causal diamonds. In two dimensions, the latter is given by a product of two copies of a two-dimensional de Sitter space. For a class of universal states, we show that the entanglement entropy and its spin-three generalization obey nonlinear equations of motion with local interactions on this moduli space, which can be identified with Liouville and Toda equations, respectively. This suggests the possibility of extending the definition of our new observables beyond the linear level more generally and in such a way that they give rise to new dynamically interacting theories on the moduli space of causal diamonds. Various challenges one has to face in order to implement this idea are discussed.

  14. 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.

  15. 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...

  16. Relationships between Western Area Power Administration`s power marketing program and hydropower operations at Salt Lake City area integrated projects

    Energy Technology Data Exchange (ETDEWEB)

    Veselka, T.D.; Folga, S.; Poch, L.A. [and others

    1995-03-01

    This technical memorandum provides background information on the Western Area Power Administration (Western) and the physical characteristics of the Salt Lake City Area Integrated Projects (SLCA/IP) hydropower plants, which include the Colorado River Storage Project, the Rio Grande Project, and the Collbran Project. In addition, the history, electrical capacity, storage capacity, and flow restrictions at each dam are presented. An overview of Western`s current programs and services, including a review of statutory authorities, agency discretion, and obligations, is also provided. The variability of SLCA/IP hourly generation under various alternative marketing strategies and purchasing programs is discussed. The effects of Western`s services, such as area load control, outage assistance, and transmission, on SLCA/IP power plant operations are analyzed.

  17. The Development of Open Water-lubricated Polycrystalline Diamond (PCD) Thrust Bearings for Use in Marine Hydrokinetic (MHK) Energy Machines

    Energy Technology Data Exchange (ETDEWEB)

    Cooley, Craig, H.; Khonsari, Michael,, M; Lingwall, Brent

    2012-11-28

    Polycrstalline diamond (PCD) bearings were designed, fabricated and tested for marine-hydro-kinetic (MHK) application. Bearing efficiency and life were evaluated using the US Synthetic bearing test facility. Three iterations of design, build and test were conducted to arrive at the best bearing design. In addition life testing that simulated the starting and stopping and the loading of real MHK applications were performed. Results showed polycrystalline diamond bearings are well suited for MHK applications and that diamond bearing technology is TRL4 ready. Based on life tests results bearing life is estimated to be at least 11.5 years. A calculation method for evaluating the performance of diamond bearings of round geometry was also investigated and developed. Finally, as part of this effort test bearings were supplied free of charge to the University of Alaska for further evaluation. The University of Alaska test program will subject the diamond bearings to sediment laden lubricating fluid.

  18. All diamond self-aligned thin film transistor

    Science.gov (United States)

    Gerbi, Jennifer [Champaign, IL

    2008-07-01

    A substantially all diamond transistor with an electrically insulating substrate, an electrically conductive diamond layer on the substrate, and a source and a drain contact on the electrically conductive diamond layer. An electrically insulating diamond layer is in contact with the electrically conductive diamond layer, and a gate contact is on the electrically insulating diamond layer. The diamond layers may be homoepitaxial, polycrystalline, nanocrystalline or ultrananocrystalline in various combinations.A method of making a substantially all diamond self-aligned gate transistor is disclosed in which seeding and patterning can be avoided or minimized, if desired.

  19. THE CONCENTRATION OF DIAMONDS INFLUENCES THE WEAR OF BEADS IN SAWING DIMENSION STONE WITH DIAMOND WIRE SAWING PLANT

    Directory of Open Access Journals (Sweden)

    Siniša Dunda

    1993-12-01

    Full Text Available The influence of diamond concentration to the wear or diamond layer and to the life time of the diamond wire has experimentally tested. The changes of the diamond concentration were achieved by changing the beads' pace per m' of diamond wire. Upon the obtained results of the experiment, the optimal concentration of diamonds has been established, also considering the least cost, per square meter of sawing (the paper is published in Croatian.

  20. The mechanical and strength properties of diamond

    Science.gov (United States)

    Field, J. E.

    2012-12-01

    Diamond is an exciting material with many outstanding properties; see, for example Field J E (ed) 1979 The Properties of Diamond (London: Academic) and Field J E (ed) 1992 The Properties of Natural and Synthetic Diamond (London: Academic). It is pre-eminent as a gemstone, an industrial tool and as a material for solid state research. Since natural diamonds grew deep below the Earth's surface before their ejection to mineable levels, they also contain valuable information for geologists. The key to many of diamond's properties is the rigidity of its structure which explains, for example, its exceptional hardness and its high thermal conductivity. Since 1953, it has been possible to grow synthetic diamond. Before then, it was effectively only possible to have natural diamond, with a small number of these found in the vicinity of meteorite impacts. Techniques are now available to grow gem quality synthetic diamonds greater than 1 carat (0.2 g) using high temperatures and pressures (HTHP) similar to those found in nature. However, the costs are high, and the largest commercially available industrial diamonds are about 0.01 carat in weight or about 1 mm in linear dimension. The bulk of synthetic diamonds used industrially are 600 µm or less. Over 75% of diamond used for industrial purposes today is synthetic material. In recent years, there have been two significant developments. The first is the production of composites based on diamond; these materials have a significantly greater toughness than diamond while still maintaining very high hardness and reasonable thermal conductivity. The second is the production at low pressures by metastable growth using chemical vapour deposition techniques. Deposition onto non-diamond substrates was first demonstrated by Spitsyn et al 1981 J. Cryst. Growth 52 219-26 and confirmed by Matsumoto et al 1982 Japan J. Appl. Phys. 21 L183-5. These developments have added further to the versatility of diamond. Two other groups of materials

  1. Microstructures and Superelasticity in Natural Diamond

    Science.gov (United States)

    Leung, I.; Winston, R.

    2002-12-01

    Diamonds of distorted shapes from Pipe 50 in China often display microstructures such as densely distributed lamellae, tweed patterns and twin-wedges growing inward from the edge. The latter two probably form precursory to major deformation systems. An X-ray investigation revealed that planar surfaces between the parent diamond and its lamellae are (-111) planes across which the lamellar structure has rotated 39 degrees, forming a "twinning" relation with the parent. This relation is no longer true when we discovered microcrysts of lonsdaleite in the lamellae, apparently derived from martensitic transformation of diamond (austenite). Metal alloy martensites formed during cooling may cause strain induced plasticity and shape distortion, but shape recovery may occur upon heating. Conversion of diamond to lonsdaleite involves very high strains, while the later is reversible if the stress is released. This phenomenon is known as superelasticity. The small amount of residual lonsdaleite remaining in the lamellae indicates that the superelastic property of diamond is quite significant. When complete reversal has restored cubic symmetry to the whole diamond, the only clue to the diamond's transformation history would lie in the distorted shape if the crystal had experienced permanent plastic deformation. This observation is important as we evaluate the mechanical properties of diamond.

  2. Trading diamonds for guns | IDRC - International Development ...

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

    2011-07-15

    Jul 15, 2011 ... Their report, The Heart of the Matter: Sierra Leone, Diamonds and Human Security, has attracted worldwide attention since it was published last year and has contributed to major changes in the international diamond industry. In 1999, the International Development Research Centre (IDRC) and several ...

  3. Large diamonds grown at high pressure conditions

    CERN Document Server

    Kanda, H

    2000-01-01

    A technique has been established to grow large diamonds up to 2 cm. The crystals are bulky polyhedron with yellow, blue, green or brown color as well as colorless, which depend on impurities. The impurities incorporated into the diamond are limited, i.e. nitrogen, boron, nickel, cobalt, silicon and phosphorus.

  4. 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...

  5. 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.

  6. Conflict diamonds — unfinished business | IDRC - International ...

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

    2011-07-22

    Jul 22, 2011 ... Even Canadian diamonds with snow geese, maple leaves, and polar bears lasered onto them disappear for a time into the sorting houses of Antwerp before they return to Canada for cutting and polishing. What we do know is that 75 percent of the world's gem diamonds are mined in Africa, and that União ...

  7. 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).

  8. 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

  9. Trace elements in Gem-Quality Diamonds - Origin and evolution of diamond-forming fluid inclusions

    Science.gov (United States)

    Pearson, Graham; Krebs, Mandy; Stachel, Thomas; Woodland, Sarah; Chinn, Ingrid; Kong, Julie

    2017-04-01

    In the same way that melt inclusions in phenocrysts have expanded our idea of melt formation and evolution in basalts, studying fluids trapped in diamonds is providing important new constraints on the nature of diamond-forming fluids. Fibrous and cloudy diamonds trap a high but variable density of fluid inclusions and so have been extensively studied using major and trace element compositions. In contrast, constraining the nature of the diamond-forming fluid for high purity gem-quality diamonds has been restricted by the rarity of available high quality trace element data. This is due to the extremely low concentrations of impurities that gem diamonds contain - often in the ppt range. The recent discovery of fluids in gem diamonds showing similar major element chemistry to fluid-rich diamonds suggest that many diamonds may share a common spectrum of parental fluids. Here we test this idea further. Recent advances in analytical techniques, in particular the development of the "off-line" laser ablation pre-concentration approach, have allowed fully quantitative trace element data to be recovered from "fluid-poor", high quality gem diamonds. We present trace element data for gem diamonds from a variety of locations from Canada, S. Africa and Russia, containing either silicate or sulphide inclusions to examine possible paragenetic or genetic differences between fluids. REE abundance in the "gem" diamonds vary from 0.1 to 0.0001 x chondrite. To a first order, we observe the same spectrum of trace element compositions in the gem diamonds as that seen in fluid-rich "fibrous" diamonds, supporting a common origin for the fluids. REE patterns range from extremely flat (Ce/Yb)n 2.5 to 5 (commonly in sulphide-bearing diamonds) to >70, the latter having significantly greater inter-element HFSE/LILE fractionation. In general, the fluids from the sulphide-bearing diamonds are less REE-enriched than the silicate-bearing diamonds, but the ranges overlap significantly. The very

  10. National Dam Safety Program. Siegmund Lake Dam (MO-30520), Missouri - Kansas City Basin. Warren County, Missouri. Phase I Inspection Report.

    Science.gov (United States)

    1981-06-01

    study as indicated in Section 5. Seepage and stability analyses comparable to the requirements of "Recommended Guidelines for Safety Inspection of Dams...lake outflow resulting from a storm of probable maximum flood magnitude, the recommended spillway design flood for this dam. In either case , the...ISTAQ ICOI’P IECON ITAPE JPT JPRTI IW( ISTAGE IAUTO INFLOW 0 0 0 0 0 1 0 0 HYDROGIdAP DATA IIYDG ILi4G TREA SA TRSDA TRSPC RATIO I S" ISAME LOCX. 1 2

  11. National Dam Inspection Program. Converse Lake Dam (CT 00044). Connecticut Coastal Basin, Greenwich, Connecticut. Phase I Inspection Report.

    Science.gov (United States)

    1980-02-01

    Rosenstiel Estate. S-: f. Operator - Mr. Fredrick Jansen (Estate Superintendent) (203)661-9168 -’ .g. Purpose of Dam - Recreational - The dam was originally...cut from the downstream slope of the dam by Mr. Jansen , the estate superintendent. N 4.3 MAINTENANCE OF OPERATING FACILITIES ft There is no known...a bre in the blooi’pn.Ts cn o esosn ,71 ncut drainn theo lake or e;: v.atng7 oac C" t J C n o -2 alor A’J 1 Ian toWld that a considerable flow

  12. 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.

  13. Fiber-Coupled Diamond Quantum Nanophotonic Interface

    Science.gov (United States)

    Burek, Michael J.; Meuwly, Charles; Evans, Ruffin E.; Bhaskar, Mihir K.; Sipahigil, Alp; Meesala, Srujan; Machielse, Bartholomeus; Sukachev, Denis D.; Nguyen, Christian T.; Pacheco, Jose L.; Bielejec, Edward; Lukin, Mikhail D.; Lončar, Marko

    2017-08-01

    Color centers in diamond provide a promising platform for quantum optics in the solid state, with coherent optical transitions and long-lived electron and nuclear spins. Building upon recent demonstrations of nanophotonic waveguides and optical cavities in single-crystal diamond, we now demonstrate on-chip diamond nanophotonics with a high-efficiency fiber-optical interface achieving >90 % power coupling at visible wavelengths. We use this approach to demonstrate a bright source of narrow-band single photons based on a silicon-vacancy color center embedded within a waveguide-coupled diamond photonic crystal cavity. Our fiber-coupled diamond quantum nanophotonic interface results in a high flux (approximately 38 kHz) of coherent single photons (near Fourier limited at chip and separated by long distances.

  14. The Charge Collection Properties of CVD Diamond

    CERN Document Server

    Behnke, T; Oh, A; Steuerer, J; Wagner, A; Zeuner, W; Behnke, Ties; Hüntemeyer, Petra; Oh, Alexander; Steuerer, Johannes; Wagner, Albrecht; Zeuner, Wolfram

    1998-01-01

    The charge collection properties of CVD diamond have been investigated with ionising radiation. In this study two CVD diamond samples, prepared with electrical contacts have been used as solid state ionisation chambers. The diamonds have been studied with beta particles and 10 keV photons, providing a homogeneous ionisation density and with protons and alpha particles which are absorbed in a thin surface layer. For the latter case a strong decrease of the signal as function of time is observed, which is attributed to polarisation effects inside the diamond. Spatially resolved measurements with protons show a large variation of the charge collection efficiency, whereas for photons and minimum ionising particles the response is much more uniform and in the order of 18%. These results indicate that the applicability of CVD diamond as a position sensitive particle detector depends on the ionisation type and appears to be promising for homogeneous ionisation densities as provided by relativistic charged particles.

  15. 75 FR 362 - Agency Information Collection Activities; Proposed Collection; Comment Request; Great Lakes...

    Science.gov (United States)

    2010-01-05

    ... Information Collection Activities; Proposed Collection; Comment Request; Great Lakes Accountability System...-line instructions for submitting comments. Mail: Great Lakes Accountability System, Attn: Rita Cestaric, EPA, Great Lakes National Program Office, 77 W. Jackson St., Chicago, Illinois 60604. Hand Delivery...

  16. National Program for Inspection of Non-Federal Dams. Lake Kanasatka Dam (NH 00125) Merrimack River Basin, Moultonboro, New Hampshire. Phase I Inspection Report.

    Science.gov (United States)

    1980-03-01

    DAMS, INSPECTION, DAM SAFETY, Merrimack River Basin Moultonboro, New Hampshire Tributary to Lake Winnipesaukee 20. ABSTRACT (Conaiw,.en aeveta...Blackey ,ve portion of Lake Winnipesaukee . The elevation difference ttween the normal water surfaces of Lake Kanasatka and Lke Winnipesaukee is...approximately 1,800 ft. downstream of the dam on the shore of Lake Winnipesaukee . Although the homes are located on the fringe of the impact area, one

  17. Diamond Machining of an Off-Axis Biconic Aspherical Mirror

    Science.gov (United States)

    Ohl, Raymond G.; Preuss, Werner; Sohn, Alex; MacKenty, John

    2009-01-01

    Two diamond-machining methods have been developed as part of an effort to design and fabricate an off-axis, biconic ellipsoidal, concave aluminum mirror for an infrared spectrometer at the Kitt Peak National Observatory. Beyond this initial application, the methods can be expected to enable satisfaction of requirements for future instrument mirrors having increasingly complex (including asymmetrical), precise shapes that, heretofore, could not readily be fabricated by diamond machining or, in some cases, could not be fabricated at all. In the initial application, the mirror is prescribed, in terms of Cartesian coordinates x and y, by aperture dimensions of 94 by 76 mm, placements of -2 mm off axis in x and 227 mm off axis in y, an x radius of curvature of 377 mm, a y radius of curvature of 407 mm, an x conic constant of 0.078, and a y conic constant of 0.127. The aspect ratio of the mirror blank is about 6. One common, "diamond machining" process uses single-point diamond turning (SPDT). However, it is impossible to generate the required off-axis, biconic ellipsoidal shape by conventional SPDT because (1) rotational symmetry is an essential element of conventional SPDT and (2) the present off-axis biconic mirror shape lacks rotational symmetry. Following conventional practice, it would be necessary to make this mirror from a glass blank by computer-controlled polishing, which costs more than diamond machining and yields a mirror that is more difficult to mount to a metal bench. One of the two present diamond machining methods involves the use of an SPDT machine equipped with a fast tool servo (FTS). The SPDT machine is programmed to follow the rotationally symmetric asphere that best fits the desired off-axis, biconic ellipsoidal surface. The FTS is actuated in synchronism with the rotation of the SPDT machine to generate the difference between the desired surface and the best-fit rotationally symmetric asphere. In order to minimize the required stroke of the FTS

  18. Biological consequences of the coaster brook trout restoration stocking program in Lake Superior tributaries with Pictured Rocks National Lakeshore

    Science.gov (United States)

    Leonard, Jill B.K.; Stott, Wendylee; Loope, Delora M.; Kusnierz, Paul C.; Sreenivasan, Ashwin

    2013-01-01

    The coaster Brook Trout Salvelinus fontinalis is a Lake Superior ecotype representing intraspecific variation that has been impacted by habitat loss and overfishing. Hatchery strains of Brook Trout derived from populations in Lake Superior were stocked into streams within Pictured Rocks National Lakeshore, Michigan, as part of an effort to rehabilitate adfluvial coaster Brook Trout. Wild and hatchery Brook Trout from three streams (Mosquito River, Hurricane River, and Sevenmile Creek) were examined for movement behavior, size, physiology, and reproductive success. Behavior and size of the stocked fish were similar to those of wild fish, and less than 15% of the stocked, tagged Brook Trout emigrated from the river into which they were stocked. There was little evidence of successful reproduction by stocked Brook Trout. Similar to the results of other studies, our findings suggest that the stocking of nonlocal Brook Trout strains where a local population already exists results in limited natural reproduction and should be avoided, particularly if the mechanisms governing the ecotype of interest are poorly understood.

  19. Shape analysis of synthetic diamond

    CERN Document Server

    Mullan, C

    1997-01-01

    Two-dimensional images of synthetic industrial diamond particles were obtained using a camera, framegrabber and PC-based image analysis software. Various methods for shape quantification were applied, including two-dimensional shape factors, Fourier series expansion of radius as a function of angle, boundary fractal analysis, polygonal harmonics, and comer counting methods. The shape parameter found to be the most relevant was axis ratio, defined as the ratio of the minor axis to the major axis of the ellipse with the same second moments of area as the particle. Axis ratio was used in an analysis of the sorting of synthetic diamonds on a vibrating table. A model was derived based on the probability that a particle of a given axis ratio would travel to a certain bin. The model described the sorting of bulk material accurately but it was found not to be applicable if the shape mix of the feed material changed dramatically. This was attributed to the fact that the particle-particle interference was not taken int...

  20. Nanopatterning of ultrananocrystalline diamond nanowires.

    Science.gov (United States)

    Wang, Xinpeng; Ocola, Leonidas E; Divan, Ralu S; Sumant, Anirudha V

    2012-02-24

    We report the fabrication of horizontally aligned ultrananocrystalline diamond (UNCD) nanowires (NWs) via two different approaches. First, with the top-down approach by using electron beam lithography (EBL) and reactive ion etching (RIE) with a photo resist layer as an etch mask. Using this approach, we demonstrate fabrication of 50 µm long UNCD NWs with widths as narrow as 40 nm. We further present an alternative approach to grow UNCD NWs at pre-defined positions through a selective seeding process. No RIE was needed either to etch the NWs or to remove the mask. In this case, we achieved UNCD NWs with lengths of 50 µm and smallest width of 90 nm respectively. Characterization of these nanowires by using scanning electron microscopy (SEM) and atomic force microscopy (AFM) shows that the UNCD NWs are well defined and fully released, with no indication of residual stress. Characterization using visible and ultraviolet (UV) Raman spectroscopy indicates that in both fabrication approaches, UNCD NWs maintain their intrinsic diamond structure.

  1. Nanopatterning of ultrananocrystalline diamond nanowires

    Science.gov (United States)

    Wang, Xinpeng; Ocola, Leonidas E.; Divan, Ralu S.; Sumant, Anirudha V.

    2012-02-01

    We report the fabrication of horizontally aligned ultrananocrystalline diamond (UNCD) nanowires (NWs) via two different approaches. First, with the top-down approach by using electron beam lithography (EBL) and reactive ion etching (RIE) with a photo resist layer as an etch mask. Using this approach, we demonstrate fabrication of 50 µm long UNCD NWs with widths as narrow as 40 nm. We further present an alternative approach to grow UNCD NWs at pre-defined positions through a selective seeding process. No RIE was needed either to etch the NWs or to remove the mask. In this case, we achieved UNCD NWs with lengths of 50 µm and smallest width of 90 nm respectively. Characterization of these nanowires by using scanning electron microscopy (SEM) and atomic force microscopy (AFM) shows that the UNCD NWs are well defined and fully released, with no indication of residual stress. Characterization using visible and ultraviolet (UV) Raman spectroscopy indicates that in both fabrication approaches, UNCD NWs maintain their intrinsic diamond structure.

  2. L-Lake macroinvertebrate community

    Energy Technology Data Exchange (ETDEWEB)

    Specht, W.L.

    1996-06-01

    To characterize the present benthic macroinvertebrate community of L-Lake, Regions 5 and 7 of the reservoir were sampled in September 1995 at the same locations sampled in 1988 and 1989 during the L-Lake monitoring program. The macroinvertebrate community of 1995 is compared to that of 1988 and 1989. The species composition of L-Lake`s macroinvertebrate community has changed considerably since 1988-1989, due primarily to maturation of the reservoir ecosystem. L-Lake contains a reasonably diverse macroinvertebrate community that is capable of supporting higher trophic levels, including a diverse assemblage of fish species. The L-Lake macroinvertebrate community is similar to those of many other southeastern reservoirs, and there is no indication that the macroinvertebrate community is perturbed by chemical or physical stressors.

  3. Diamond formation - Where, when and how?

    Science.gov (United States)

    Stachel, T.; Luth, R. W.

    2015-04-01

    Geothermobarometric calculations for a worldwide database of inclusions in diamond indicate that formation of the dominant harzburgitic diamond association occurred predominantly (90%) under subsolidus conditions. Diamonds in eclogitic and lherzolitic lithologies grew in the presence of a melt, unless their formation is related to strongly reducing CHO fluids that would increase the solidus temperature or occurred at pressure-temperature conditions below about 5 GPa and 1050 °C. Three quarters of peridotitic garnet inclusions in diamond classify as "depleted" due to their low Y and Zr contents but, based on LREEN-HREEN ratios invariably near or greater than one, they nevertheless reflect re-enrichment through either highly fractionated fluids or small amounts of melt. The trace element signatures of harzburgitic and lherzolitic garnet inclusions are broadly consistent with formation under subsolidus and supersolidus conditions, respectively. Diamond formation may be followed by cooling in the range of ~ 60-180 °C as a consequence of slow thermal relaxation or, in the case of the Kimberley area in South Africa, possibly uplift due to extension in the lithospheric mantle. In other cases, diamond formation and final residence took place at comparable temperatures or even associated with small temperature increases over time. Diamond formation in peridotitic substrates can only occur at conditions at least as reducing as the EMOD buffer. Evaluation of the redox state of 225 garnet peridotite xenoliths from cratons worldwide indicates that the vast majority of samples deriving from within the diamond stability field represent fO2 conditions below EMOD. Modeling reveals that less than 50 ppm fluid are required to completely reset the redox state of depleted cratonic peridotite to that of the fluid. Consequently, the overall reduced state of diamond stable peridotites implies that the last fluids to interact with the deep cratonic lithosphere were generally reducing in

  4. 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

  5. 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.

  6. Cutting applications of DLC, hard carbon and diamond films

    OpenAIRE

    Vandevelde, Thierry; VANDIERENDONCK, Kristine; VAN STAPPEN, M; Mong, W. D.; Perremans, P

    1999-01-01

    Due to their high hardness and low friction coefficient, diamond-like carbon (DLC), amorphous hard carbon (HC), and diamond coatings have great potential for dry cutting operations. The main differences between these coatings can be found in their hardness (respectively 2500, 5000-8000 and 10000 HV), morphology (DLC and HC: amorphous and diamond: crystalline) and their thermal stability (DLC, 250 degrees C, HC: 600 degrees C and diamond: 700 degrees C). DLC, HC and CVD diamond-coated hard ins...

  7. Bonding Diamond To Metal In Electronic Circuits

    Science.gov (United States)

    Jacquez, Andrew E.

    1993-01-01

    Improved technique for bonding diamond to metal evolved from older technique of soldering or brazing and more suitable for fabrication of delicate electronic circuits. Involves diffusion bonding, developed to take advantage of electrically insulating, heat-conducting properties of diamond, using small diamond bars as supports for slow-wave transmission-line structures in traveling-wave-tube microwave amplifiers. No fillets or side coats formed because metal bonding strips not melted. Technique also used to mount such devices as transistors and diodes electrically insulated from, but thermally connected to, heat sinks.

  8. 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

  9. Deep depletion concept for diamond MOSFET

    Science.gov (United States)

    Pham, T. T.; Rouger, N.; Masante, C.; Chicot, G.; Udrea, F.; Eon, D.; Gheeraert, E.; Pernot, J.

    2017-10-01

    A stable deep depletion regime is demonstrated in metal oxide semiconductor capacitors using p -type oxygen-terminated (100) diamond as a semiconductor and Al2O3 deposited by Atomic Layer Deposition at 380 °C. Current voltage I(V) and capacitance voltage C(V) measurements were performed to evaluate the effectiveness of diamond semiconductor gate control. An effective modulation of the space charge region width is obtained by the gate bias, where the deep depletion regime is demonstrated for a positive gate bias. The deep depletion concept is described and proposed for MOSFET devices. Finally, a proof of concept of diamond deep depletion MOSFETs is presented.

  10. Playa Lakes

    Data.gov (United States)

    Kansas Data Access and Support Center — This digital dataset provides information about the spatial distribution of soil units associated with playa lakes. Specific soil types have been designated by the...

  11. Lake Cadagno

    DEFF Research Database (Denmark)

    Tonolla, Mauro; Storelli, Nicola; Danza, Francesco

    2017-01-01

    Lake Cadagno (26 ha) is a crenogenic meromictic lake located in the Swiss Alps at 1921 m asl with a maximum depth of 21 m. The presence of crystalline rocks and a dolomite vein rich in gypsum in the catchment area makes the lake a typical “sulphuretum ” dominated by coupled carbon and sulphur...... cycles. The chemocline lies at about 12 m depth, stabilized by density differences of salt-rich water supplied by sub-aquatic springs to the monimolimnion and of electrolyte-poor surface water feeding the mixolimnion. Steep sulphide and light gradients in the chemocline support the growth of a large...... in the chemocline. Small-celled PSB together with the sulfate-reducing bacterium Desulfocapsa thiozymogenes sp. form stable aggregates in the lake, which represent small microenvironments with an internal sulphur cycle. Eukaryotic primary producers in the anoxic zones are dominated by Cryptomonas phaseolus...

  12. First principles study of Fe in diamond: A diamond-based half metallic dilute magnetic semiconductor

    Science.gov (United States)

    Benecha, E. M.; Lombardi, E. B.

    2013-12-01

    Half-metallic ferromagnetic ordering in semiconductors, essential in the emerging field of spintronics for injection and transport of highly spin polarised currents, has up to now been considered mainly in III-V and II-VI materials. However, low Curie temperatures have limited implementation in room temperature device applications. We report ab initio Density Functional Theory calculations on the properties of Fe in diamond, considering the effects of lattice site, charge state, and Fermi level position. We show that the lattice sites and induced magnetic moments of Fe in diamond depend strongly on the Fermi level position and type of diamond co-doping, with Fe being energetically most favorable at the substitutional site in p-type and intrinsic diamond, while it is most stable at a divacancy site in n-type diamond. Fe induces spin polarized bands in the band gap, with strong hybridization between Fe-3d and C-2s,2p bands. We further consider Fe-Fe spin interactions in diamond and show that substitutional Fe+1 in p-type diamond exhibits a half-metallic character, with a magnetic moment of 1.0 μB per Fe atom and a large ferromagnetic stabilization energy of 33 meV, an order of magnitude larger than in other semiconductors, with correspondingly high Curie temperatures. These results, combined with diamond's unique properties, demonstrate that Fe doped p-type diamond is likely to be a highly suitable candidate material for spintronics applications.

  13. ULTRAFINE FLUORESCENT DIAMONDS IN NANOTECHNOLOGY

    Directory of Open Access Journals (Sweden)

    Kanyuk M. I.

    2014-07-01

    Full Text Available The purpose of the work is to summarize the literature data concerning ultrafine diamonds, namely their industrial production, as well as considerable photostability and biocompatibility that promote their use in modern visualization techniques. It is shown that due to the unique physical properties, they are promising materials for using in nanotechnology in the near future. Possibility of diverse surface modification, small size and large absorption surface are the basis for their use in different approaches for drug and gene delivery into a cell. The changes in the properties of nanodiamond surface modification methods of their creation, stabilization and applications are described. It can be said that fluorescent surface-modified nanodiamonds are a promising target in various research methods that would be widely used for labeling of living cells, as well as in the processes of genes and drugs delivery into a cell.

  14. Documentation of a computer program to simulate lake-aquifer interaction using the MODFLOW ground water flow model and the MOC3D solute-transport model

    Science.gov (United States)

    Merritt, Michael L.; Konikow, Leonard F.

    2000-01-01

    Heads and flow patterns in surficial aquifers can be strongly influenced by the presence of stationary surface-water bodies (lakes) that are in direct contact, vertically and laterally, with the aquifer. Conversely, lake stages can be significantly affected by the volume of water that seeps through the lakebed that separates the lake from the aquifer. For these reasons, a set of computer subroutines called the Lake Package (LAK3) was developed to represent lake/aquifer interaction in numerical simulations using the U.S. Geological Survey three-dimensional, finite-difference, modular ground-water flow model MODFLOW and the U.S. Geological Survey three-dimensional method-of-characteristics solute-transport model MOC3D. In the Lake Package described in this report, a lake is represented as a volume of space within the model grid which consists of inactive cells extending downward from the upper surface of the grid. Active model grid cells bordering this space, representing the adjacent aquifer, exchange water with the lake at a rate determined by the relative heads and by conductances that are based on grid cell dimensions, hydraulic conductivities of the aquifer material, and user-specified leakance distributions that represent the resistance to flow through the material of the lakebed. Parts of the lake may become ?dry? as upper layers of the model are dewatered, with a concomitant reduction in lake surface area, and may subsequently rewet when aquifer heads rise. An empirical approximation has been encoded to simulate the rewetting of a lake that becomes completely dry. The variations of lake stages are determined by independent water budgets computed for each lake in the model grid. This lake budget process makes the package a simulator of the response of lake stage to hydraulic stresses applied to the aquifer. Implementation of a lake water budget requires input of parameters including those representing the rate of lake atmospheric recharge and evaporation

  15. Diamond crystals for H^{-} injection

    Directory of Open Access Journals (Sweden)

    U. I. Uggerhøj

    2002-07-01

    Full Text Available There are several advantages in using a crystal for stripping of the H^{-} ion to obtain efficient injection of protons into a circular accelerator. First, the stripping efficiency of a crystal is at least as large as for an amorphous foil of the same substance and thickness. Second, the emittance increase imposed by the multiple Coulomb scattering of the protons on subsequent turns is drastically lower by a factor of up to ≃7. Third, the restricted energy loss of the protons is lower by a factor of up to ≃1.5—this, combined with the fact that the thermal conductivity of a single crystal of diamond is much higher than that of the amorphous material, will reduce the effect of heating of the stripping material. In high-power schemes based on amorphous foils heating of the electron stripping material is a limiting factor. Fourth, the reduced total energy loss is accompanied by a smaller energy loss straggling implying a smaller longitudinal emittance. Last, the so-called random orientation of the crystal can provide the option of stripping the H^{-} ions as in an amorphous foil while preserving the advantage of a high thermal conductivity, simply by changing the orientation of the crystal. A simulation using realistic parameters is presented, which reflects the efficient conservation of emittance using a diamond crystal. The phenomenon should in fact be applicable in general for the stripping of H^{-}, although the advantages depend on parameters such as the energy. A reasonable figure of merit is the ratio of the total transverse emittance increase of crystalline and amorphous foils in one turn and in the presented case this is as high as a factor 3.9.

  16. White Lake AOC

    Science.gov (United States)

    White Lake is in Muskegon County along the eastern shore of Lake Michigan. It was named an Area of Concern on the Great Lakes under the Great Lakes Water Quality Agreement of 1987 and delisted in 2014.

  17. Eclipse Megamovie Citizen Science: The Diamond Ring

    Science.gov (United States)

    Hudson, H. S.; Mcintosh, S. W.; Martinez Oliveros, J. C.; Pasachoff, J. M.; Peticolas, L. M.; Bender, M.

    2016-12-01

    The 2017 North American total eclipse has begun to encourage many outreach and citizen-science activiites. We describe here a part of the Eclipse Megamovie program, in which we deploy a smartphone app to enable anybody with a GPS-equipped smartphone to record correct images of Baily's Beads (the "Diamond Ring" effect) for subsequent analysis. The multiply oversampled recordings of 2nd and 3rd contacts, across and along the track, will provide material for unique movie representations of the astronomical phenomenon. After the fact, this highly oversampled dataset can be used to confirm and/or extend detailed satellite topography of the Moon from Kaguya and LRO. In addition the high angular resolution inherent in the "knife-edge" motion will provide a unique view of the structure of the solar limb itself. The low angular resolution of the smartphone cameras is a handicap, but excellent time resolution and massive oversampling are great advantages. We anticipate public participation in image selection to get the best sequences of last few-millisecond imagery for the science product here, which can follow the known motions of the solar limb due to p-modes and granulation. No comparable database exists, and so the final product of this crowdsourcing will be a public archive of the data and metadata for future studies.

  18. Diamond coated silicon field emitter array

    Energy Technology Data Exchange (ETDEWEB)

    S. Albin; W. Fu; A. Varghese; A. C. Lavarias; G. R. Myneni

    1999-07-01

    Diamond coated silicon tip arrays, with and without a self-aligned gate, were fabricated, and current-voltage characteristics of 400 tips were measured. Diamond films were grown uniformly on Si tips using microwave plasma after nucleation with 10 nm diamond suspension and substrate bias. An emission current of 57 ?A was obtained at 5 V from the ungated array tips separated from an anode at 2 ?m. In the case of the gated arrays with 1.5 ?m aperture, an emission current of 3.4 ?A was measured at a gate voltage of 80 V for an anode separation of 200 ?m. The turn-on voltages for these two types of devices were 0.2 and 40 V, respectively. Diamond coated Si tip arrays have potential applications in field emission based low voltage vacuum electronic devices and microsensors.

  19. The DIAMOND Model of Peace Support Operations

    National Research Council Canada - National Science Library

    Bailey, Peter

    2005-01-01

    DIAMOND (Diplomatic And Military Operations in a Non-warfighting Domain) is a high-level stochastic simulation developed at Dstl as a key centerpiece within the Peace Support Operations (PSO) 'modelling jigsaw...

  20. 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...

  1. Diamond switches for high temperature electronics

    Energy Technology Data Exchange (ETDEWEB)

    Prasad, R.R.; Rondeau, G.; Qi, Niansheng [Alameda Applied Sciences Corp., San Leandro, CA (United States)] [and others

    1996-04-25

    Diamond switches are well suited for use in high temperature electronics. Laboratory feasibility of diamond switching at 1 kV and 18 A was demonstrated. DC blocking voltages up to 1 kV were demonstrated. A 50 {Omega} load line was switched using a diamond switch, with switch on-state resistivity {approx}7 {Omega}-cm. An electron beam, {approx}150 keV energy, {approx}2 {mu}s full width at half maximum was used to control the 5 mm x 5 mm x 100 {mu}m thick diamond switch. The conduction current temporal history mimics that of the electron beam. These data were taken at room temperature.

  2. Ultra-fast calculations using diamond

    NARCIS (Netherlands)

    Van Dijk, T.

    2011-01-01

    TU Delft researchers have managed to use a piece of diamond to hold four quantum bits that can be spun, flipped and entangled with each other. This is an important step towards a working quantum computer

  3. Nanocrystalline hexagonal diamond formed from glassy carbon

    OpenAIRE

    Shiell, Thomas. B.; McCulloch, Dougal G.; Bradby, Jodie E.; Haberl, Bianca; Boehler, Reinhard; McKenzie, David. R.

    2016-01-01

    Carbon exhibits a large number of allotropes and its phase behaviour is still subject to significant uncertainty and intensive research. The hexagonal form of diamond, also known as lonsdaleite, was discovered in the Canyon Diablo meteorite where its formation was attributed to the extreme conditions experienced during the impact. However, it has recently been claimed that lonsdaleite does not exist as a well-defined material but is instead defective cubic diamond formed under high pressure a...

  4. Low-stress doped ultrananocrystalline diamond

    Science.gov (United States)

    Sumant, Anirudha V.; Buja, Federico; van Spengen, Willem Merlijn

    2016-10-25

    Nanocrystalline diamond coatings exhibit stress in nano/micro-electro mechanical systems (MEMS). Doped nanocrstalline diamond coatings exhibit increased stress. A carbide forming metal coating reduces the in-plane stress. In addition, without any metal coating, simply growing UNCD or NCD with thickness in the range of 3-4 micron also reduces in-plane stress significantly. Such coatings can be used in MEMS applications.

  5. Nanocrystalline diamond enhanced thickness shear mode resonator

    OpenAIRE

    WILLIAMS, Oliver; MORTET, Vincent; DAENEN, Michael; HAENEN, Ken

    2007-01-01

    A nanocrystalline diamond coated thickness shear mode resonator has been fabricated as an alternative to the quartz crystal microbalance. Due to the low temperature phase transition of quartz, the piezoelectric material was replaced with langasite, a piezoelectric with no phase transition up to its melting point. The resulting device shows clear resonant behavior and oscillates in both air and in liquid. The diamond coating shows clear faceting by scanning electron microscopy and sp(3) bondin...

  6. Nanocrystalline diamond enhanced thickness shear mode resonator

    Science.gov (United States)

    Williams, Oliver A.; Mortet, Vincent; Daenen, Michael; Haenen, Ken

    2007-02-01

    A nanocrystalline diamond coated thickness shear mode resonator has been fabricated as an alternative to the quartz crystal microbalance. Due to the low temperature phase transition of quartz, the piezoelectric material was replaced with langasite, a piezoelectric with no phase transition up to its melting point. The resulting device shows clear resonant behavior and oscillates in both air and in liquid. The diamond coating shows clear faceting by scanning electron microscopy and sp3 bonding by Raman spectroscopy.

  7. High electrical resistivity of CVD-diamond

    OpenAIRE

    Manca, Jean; Nesladek, Milos; Neelen, M; QUAEYHAEGENS, Carl; De Schepper, Luc; de Ceuninck, Ward

    1999-01-01

    Due to its combination of excellent thermo-mechanical properties and electrical properties such as the high electrical resistivity and high dielectric strength, diamond seems a promising material for specialized dielectric applications. Due to the great advances in the growth technology of diamond films by chemical vapour deposition (CVD) on e.g. Si-substrates, new applications can be expected in microelectronics. An important technological result for dielectric applications is that high elec...

  8. Family Forest Landowners' Interest in Forest Carbon Offset Programs: Focus Group Findings from the Lake States, USA

    Science.gov (United States)

    Miller, Kristell A.; Snyder, Stephanie A.; Kilgore, Mike A.; Davenport, Mae A.

    2014-12-01

    In 2012, focus groups were organized with individuals owning 20+ acres in the Lake States region of the United States (Michigan, Minnesota, and Wisconsin) to discuss various issues related to forest carbon offsetting. Focus group participants consisted of landowners who had responded to an earlier mail-back survey (2010) on forest carbon offsets. Two focus groups were held per state with an average of eight participants each (49 total). While landowner participant types varied, overall convergence was reached on several key issues. In general, discussion results found that the current payment amounts offered for carbon credits are not likely, on their own, to encourage participation in carbon markets. Landowners are most interested in other benefits they can attain through carbon management (e.g., improved stand species mix, wildlife, and trails). Interestingly, landowner perceptions about the condition of their own forest land were most indicative of prospective interest in carbon management. Landowners who felt that their forest was currently in poor condition, or did not meet their forest ownership objectives, were most interested in participating. While the initial survey sought landowner opinions about carbon markets, a majority of focus group participants expressed interest in general carbon management as a means to achieve reduced property taxes.

  9. PDC (polycrystalline diamond compact) bit research at Sandia National Laboratories

    Energy Technology Data Exchange (ETDEWEB)

    Finger, J.T.; Glowka, D.A.

    1989-06-01

    From the beginning of the geothermal development program, Sandia has performed and supported research into polycrystalline diamond compact (PDC) bits. These bits are attractive because they are intrinsically efficient in their cutting action (shearing, rather than crushing) and they have no moving parts (eliminating the problems of high-temperature lubricants, bearings, and seals.) This report is a summary description of the analytical and experimental work done by Sandia and our contractors. It describes analysis and laboratory tests of individual cutters and complete bits, as well as full-scale field tests of prototype and commercial bits. The report includes a bibliography of documents giving more detailed information on these topics. 26 refs.

  10. Orientation relationship between diamond and magnesiochromite inclusions

    Science.gov (United States)

    Alvaro, Matteo; Angel, Ross; Nimis, Paolo; Milani, Sula; Harris, Jeff; Nestola, Fabrizio

    2017-04-01

    The correct determination of the relative crystallographic orientations of single crystals has many applications. When single crystals undergo phase transitions, especially at high pressures, the relative orientations of the two phases yields insights into transition mechanisms (Dobson et al 2013). On the other hand, determination of the crystallographic orientations of minerals included in diamonds can provide insights into the mechanisms of their entrapment and the timing of their formation relative to the host diamond (e.g. Nestola et al. 2014, Milani et al. 2016). The reported occurrence of non-trivial orientations for some minerals in diamonds, suggesting an epitaxial relationship, has long been considered to reflect contemporaneous growth of the diamond and the inclusion (e.g. syngenesis). Correct interpretation of such orientations requires (i) a statistically significant crystallographic data set for single and multiple inclusions in a large number of diamonds, and (ii) a robust data-processing method, capable of removing ambiguities derived from the high symmetry of the diamond and the inclusion. We have developed a software to perform such processing (OrientXplot, Angel et al. 2015), starting from crystallographic orientation matrixes obtained by X-ray diffractometry or EBSD data. Previous studies of inclusions in lithospheric diamonds, by single-crystal X-ray diffraction and EBSD, indicate a wide variety in the orientations of different inclusion phases with respect to their diamond host (Futergendler & Frank-Kamenetsky 1961; Frank-Kamenetsky 1964; Wiggers de Vries et al. 2011; Nestola et al. 2014, Milani et al. 2016). For example, olivine inclusions in lithospheric diamonds from Udachnaya do not show any preferred orientations with respect to their diamond hosts, but multiple inclusions in a single diamond often show very similar orientations within few degrees. In the present work on magnesiochromite inclusions in diamonds from Udachnaya, there is a

  11. Effects of catalyst height on diamond crystal morphology under high pressure and high temperature

    Science.gov (United States)

    Ya-Dong, Li; Xiao-Peng, Jia; Bing-Min, Yan; Ning, Chen; Chao, Fang; Yong, Li; Hong-An, Ma

    2016-04-01

    The effect of the catalyst height on the morphology of diamond crystal is investigated by means of temperature gradient growth (TGG) under high pressure and high temperature (HPHT) conditions with using a Ni-based catalyst in this article. The experimental results show that the morphology of diamond changes from an octahedral shape to a cub-octahedral shape as the catalyst height rises. Moreover, the finite element method (FEM) is used to simulate the temperature field of the melted catalyst/solvent. The results show that the temperature at the location of the seed diamond continues to decrease with the increase of catalyst height, which is conducive to changing the morphology of diamond. This work provides a new way to change the diamond crystal morphology. Project supported by the National Natural Science Foundation of China (Grant No. 51172089), the Program for New Century Excellent Talents in University, the Natural Science Foundation of Guizhou Provincial Education Department (Grant No. KY[2013]183), and the Collaborative Fund of Science and Technology Office of Guizhou Province, China (Grant No. LH[2015]7232).

  12. Electrical Resistivity of Natural Diamond and Diamond Films Between Room Temperature and 1200 C: Status Update

    Science.gov (United States)

    Vandersande, Jan W.; Zoltan, L. D.

    1993-01-01

    The electrical resistivity of diamond films has been measured between room temperature and 1200 C. The films were grown by either microwave Plasma CVD or combustion flame at three different places. The resistivities of the current films are compared to those measured for both natural IIa diamond and films grown only one to two years ago.

  13. Developments in FTIR spectroscopy of diamonds and better constraints on diamond thermal histories

    Science.gov (United States)

    Kohn, Simon; Speich, Laura; Smith, Christopher; Bulanova, Galina

    2017-04-01

    Fourier Transform Infrared (FTIR) spectroscopy is a commonly-used technique for investigating diamonds. It gives the most useful information if spatially-resolved measurements are used [1]. In this contribution we discuss the best way to acquire and present FTIR data from diamonds, using examples from Murowa (Zimbabwe), Argyle (Australia) and Machado River (Brazil). Examples of FTIR core-to-rim line scans, maps with high spatial resolution and maps with high spectral resolution that are fitted to extract the spatial variation of different nitrogen and hydrogen defects are presented. Model mantle residence temperatures are calculated from the concentration of A and B nitrogen-containing defects in the diamonds using known times of annealing in the mantle. A new, two-stage thermal annealing model is presented that better constrains the thermal history of the diamond and that of the mantle lithosphere in which the diamond resided. The effect of heterogeneity within the analysed FTIR volume is quantitatively assessed and errors in model temperatures that can be introduced by studying whole diamonds instead of thin plates are discussed. The kinetics of platelet growth and degradation will be discussed and the potential for two separate, kinetically-controlled defect reactions to be used to constrain a full thermal history of the diamond will be assessed. [1] Kohn, S.C., Speich, L., Smith, C.B. and Bulanova, G.P., 2016. FTIR thermochronometry of natural diamonds: A closer look. Lithos, 265, pp.148-158.

  14. 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.

  15. Mechanical properties of chemical vapor deposited diamond

    Science.gov (United States)

    Kant, Avinash

    The hardness, elastic modulus, subcritical crack growth and fracture toughness of chemical vapor deposited (CVD) polycrystalline diamond films have been investigated on thick (˜100 to 300 mum) free-standing films with regard to the composition, microstructure, failure mechanisms and measurement techniques. The rationale for this study was the uncertainty in measuring these properties in previous research and the variability in the composition and microstructure of the material, which may affect these properties. Two predominant micro-hardness measurement techniques, namely Vickers and Knoop indentation, were employed. Existing Young's modulus measurement techniques such as dynamic resonance and nano-indentation were reviewed for modulus measurement on these films. The validity of indentation fracture toughness measurement for CVD diamond films using micro-hardness indentation has been established based on comparison with the conventional method of tensile testing of pre-notched compact-tension samples. The fracture toughness, Ksbc, of diamond was measured using indentation methods and for the first time by the tensile testing of pre-notched fracture-mechanics type compact-tension samples. Measured Ksbc values were found to be between 5 and 7 MPa-msp{1/2} by either method. Studies on subcritical crack growth (i.e., at stress intensities less than Ksbc) indicated that CVD diamond is essentially immune to stress-corrosion cracking under sustained loads in room air, water and acid environments. Extensive studies of the microstructure and mechanisms of failure were conducted. A commonly known toughening mechanism for ceramics by weakening the grain boundary in order to promote intergranular failure and grain bridging, has been implemented to improve the toughness of CVD diamond films. Several films with nominally the same thickness but small differences in their non-diamond content were studied and a significant variation in the toughness measurements was observed

  16. Rehabilitation of Delavan Lake, Wisconsin

    Science.gov (United States)

    Robertson, Dale M.; Goddard, Gerald L.; Helsel, D.R.; MacKinnon, Kevin L.

    2009-01-01

    A comprehensive rehabilitation plan was developed and implemented to shift Delavan Lake, Wisconsin, from a hypereutrophic to a mesotrophic condition. The plan was threefold: (1) reduce external phosphorus (P) loading by applying Best Management Practices in the watershed, enhance an existing wetland, and short-circuit the inflows through the lake, (2) reduce internal P loading by treating the sediments with alum and removing carp, and (3) rehabilitate the fishery by removing carp and bigmouth buffalo and adding piscivores (biomanipulation). The first and second parts of the plan met with only limited success. With only minor reductions in internal and external P loading, P concentrations in the lake returned to near pre-treatment concentrations. The intensive biomanipulation and resulting trophic cascade (increased piscivores, decreased planktivores, increased large zooplankton populations, and reduced phytoplankton populations) eliminated most of the original problems in the lake (blue-green algal blooms and limited water clarity). However, now there is extensive macrophyte growth and abundant filamentous algae. Without significantly reducing the sources of the problems (high P loading) in Delavan Lake, the increased water clarity may not last. With an improved understanding of the individual components of this rehabilitation program, better future management plans can be developed for Delavan Lake and other lakes and reservoirs with similar eutrophication problems.

  17. Fast ion transport in solids: electrolytes and electrodes. Program and abstracts. [Lake Geneva, Wisconsin, May 21-25, 1979

    Energy Technology Data Exchange (ETDEWEB)

    None

    1979-01-01

    Abstracts for the 47 invited papers and 111 contributed papers (presented in poster sessions) are given in this publication, along with the program schedule. Papers deal with both basic research and applications, the most important of the latter being electric batteries. (RWR)

  18. Great Lakes

    Science.gov (United States)

    Edsall, Thomas A.; Mac, Michael J.; Opler, Paul A.; Puckett Haecker, Catherine E.; Doran, Peter D.

    1998-01-01

    The Great Lakes region, as defined here, includes the Great Lakes and their drainage basins in Minnesota, Wisconsin, Illinois, Indiana, Ohio, Pennsylvania, and New York. The region also includes the portions of Minnesota, Wisconsin, and the 21 northernmost counties of Illinois that lie in the Mississippi River drainage basin, outside the floodplain of the river. The region spans about 9º of latitude and 20º of longitude and lies roughly halfway between the equator and the North Pole in a lowland corridor that extends from the Gulf of Mexico to the Arctic Ocean.The Great Lakes are the most prominent natural feature of the region (Fig. 1). They have a combined surface area of about 245,000 square kilometers and are among the largest, deepest lakes in the world. They are the largest single aggregation of fresh water on the planet (excluding the polar ice caps) and are the only glacial feature on Earth visible from the surface of the moon (The Nature Conservancy 1994a).The Great Lakes moderate the region’s climate, which presently ranges from subarctic in the north to humid continental warm in the south (Fig. 2), reflecting the movement of major weather masses from the north and south (U.S. Department of the Interior 1970; Eichenlaub 1979). The lakes act as heat sinks in summer and heat sources in winter and are major reservoirs that help humidify much of the region. They also create local precipitation belts in areas where air masses are pushed across the lakes by prevailing winds, pick up moisture from the lake surface, and then drop that moisture over land on the other side of the lake. The mean annual frost-free period—a general measure of the growing-season length for plants and some cold-blooded animals—varies from 60 days at higher elevations in the north to 160 days in lakeshore areas in the south. The climate influences the general distribution of wild plants and animals in the region and also influences the activities and distribution of the human

  19. 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.

  20. Nanocrystalline hexagonal diamond formed from glassy carbon

    Science.gov (United States)

    Shiell, Thomas. B.; McCulloch, Dougal G.; Bradby, Jodie E.; Haberl, Bianca; Boehler, Reinhard; McKenzie, David. R.

    2016-11-01

    Carbon exhibits a large number of allotropes and its phase behaviour is still subject to significant uncertainty and intensive research. The hexagonal form of diamond, also known as lonsdaleite, was discovered in the Canyon Diablo meteorite where its formation was attributed to the extreme conditions experienced during the impact. However, it has recently been claimed that lonsdaleite does not exist as a well-defined material but is instead defective cubic diamond formed under high pressure and high temperature conditions. Here we report the synthesis of almost pure lonsdaleite in a diamond anvil cell at 100 GPa and 400 °C. The nanocrystalline material was recovered at ambient and analysed using diffraction and high resolution electron microscopy. We propose that the transformation is the result of intense radial plastic flow under compression in the diamond anvil cell, which lowers the energy barrier by “locking in” favourable stackings of graphene sheets. This strain induced transformation of the graphitic planes of the precursor to hexagonal diamond is supported by first principles calculations of transformation pathways and explains why the new phase is found in an annular region. Our findings establish that high purity lonsdaleite is readily formed under strain and hence does not require meteoritic impacts.

  1. Physical-chemical processes of diamond grinding

    Science.gov (United States)

    Lobanov, D. V.; Arhipov, P. V.; Yanyushkin, A. S.; Skeeba, V. Yu

    2017-10-01

    The article focuses on the relevance of the research into the problem of diamond abrasive metal-bonded tool performance loss with a view to enhancing the effectiveness of high-strength materials finishing processing. The article presents the results of theoretical and empirical studies of loading layer formation on the surface of diamond wheels during processing high-strength materials. The theoretical part deals with the physical and chemical processes at the contact area of the diamond wheel and work surface with the viewpoint of the electrochemical potentials equilibrium state. We defined dependencies for calculating the loading layer dimensions. The practical part of work centers on various electron-microscopic, spectral and X-ray diffraction studies of the metal-bonded wheel samples during diamond grinding. The analysis of the research results revealed the composition and structure of the loading layer. The validity of the theoretical data is confirmed by sufficient convergence of the calculated values with the results of empirical research. In order to reduce the intensity of loading and improve the cutting properties of metal-bonded diamond abrasive tools, it is recommended to use combined methods for more efficient processing of high-strength materials.

  2. 76 FR 62085 - Great Lakes Pilotage Advisory Committee

    Science.gov (United States)

    2011-10-06

    ... SECURITY Coast Guard Great Lakes Pilotage Advisory Committee AGENCY: Coast Guard, DHS. ACTION: Committee... the Federal Register of October 4, 2011, a notice announcing a Great Lakes Pilotage Advisory Committee... authority of the Great Lakes Pilotage program. If you have been adversely affected by the one-day delay in...

  3. 75 FR 22892 - Environmental Impact Statement: Salt Lake County, UT

    Science.gov (United States)

    2010-04-30

    ... Federal Highway Administration Environmental Impact Statement: Salt Lake County, UT AGENCY: Federal... transportation improvement project in Salt Lake County, Utah. FOR FURTHER INFORMATION CONTACT: Edward Woolford, Environmental Program Manager, Federal Highway Administration, 2520 West 4700 South, Suite 9A, Salt Lake City...

  4. Diamond Provenance Through Shape, Colour, Surface Features and Value

    Science.gov (United States)

    Harris, J.

    2002-05-01

    The physical properties of diamond provide a possible means by which run-of-mine productions may be identified. Such properties as shape, the regularity and angularity of the crystal form, the level of transparency, colour, syngenetic inclusion content and surface feature characteristics, all as a function of diamond size, can classify diamond productions. In early work, up to 1500 diamonds in specific sizes ranging from just under 2mm up to 6mm were evaluated. Using this procedure, most of the diamonds from the main mines in southern Africa have now been classified. Within South Africa, the mine at Swartruggens is the only one to have measurable levels of cube-shaped diamonds and an absence of the spinel twin form of diamond, more commonly known as the macle. In Botswana, the proportion of cube related forms at Jwaneng is about four times that at Orapa. Whilst the common diamond colours, colourless, yellow and brown, occur in most mines, there is a marked change in the proportion of transparent green-coated diamonds with depth in mines such as Finsch and Jwaneng. Individual mines may also have very small proportions of distinctive diamond colours, such as pinks at the Argyle mine in Australia and blues in the Premier mine in South Africa. More recently, classification emphasis has shifted away from large numbers of diamonds examined and particular attention has been paid to surface features, which reflect changes to the diamond either whilst still in the kimberlite, or subsequently during transport to an alluvial source. A classification of diamonds at the Venetia mine, South Africa, for example, showed that the proportion of diamonds with the feature referred to as corrosion sculpture, was distinctive between kimberlite types within the mine. With alluvial diamonds, transport causes further defects, particularly a general increase in the proportion of diamonds with surface features referred to as percussion marks and edge abrasion. The above observational

  5. 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

  6. Design and characterization of a novel diamond resonator

    OpenAIRE

    Maricar, Mohamed Ismaeel; Glover, James; Evans, Gwynne; Khalid, Ata-ul-Habib; Cumming, David; Oxley, Chris

    2014-01-01

    In this article, the resonant frequency and quality factor of a novel coplanar waveguide (cpw) diamond-shaped resonator were analyzed using advanced design system-2009 momentum model software. The diamond resonator was compared with the cpw radial stub resonator on gallium arsenide (GaAs); the work indicated that the diamond resonator had a smaller physical size and higher quality factor (Q) at millimetric wave frequencies. Experimentally measured diamond cpw resonators fabricated on GaAs wer...

  7. Feasibility Study of Shoreline Protection and Lake Level Regulation for Lake Ontario. Reconnaissance Report. Volume I. Main Report.

    Science.gov (United States)

    1981-11-01

    trout popula- tions are expected to rebound due to sea lamprey control efforts and impor- tant ongoing lake trout restocking programs. Wildlife...protecting the shores of property on the Atlantic and Pacific Oceans, the Gulf of Mexico, the Great Lakes, and lakes, estuaries, and bays, directly connected

  8. National Program for Inspection of Non-Federal Dams, Merrymeeting Lake Dam (NH 00342), Merrimack River Basin, New Durham, New Hampshire. Phase I Inspection Report.

    Science.gov (United States)

    1978-10-01

    Durham. The Merrymeeting River is a tributary of Lake Winnipesaukee , and part of the Merrimack River Basin. b. Description of Dam and Appurtenances...An-AmI6 448 NATIONAL PIOMaAN FOR INSPECTION OF NON-FEDIRAL GAIS I/L MERRYlIETINO LAKE OA..IUI CORPS OF ENGINEERS at LIHA MA NEW ENGLANO OIV OCT 78 N...C t A mSSmIF I F/ 13/13 NL /I’I/ll IIIIINONEI i •on 1 -1 2 5 11111 -li 6 I MERRIMACK RIVER BASIN NEW DURHAM, NEW HAMPSHIRF In MERRYMEETING LAKE DAM N

  9. Local Structure of Liquid Carbon Controls Diamond Nucleation

    NARCIS (Netherlands)

    Ghiringhelli, L.M.; Valeriani, C.; Meijer, E.J.; Frenkel, D.

    2007-01-01

    Diamonds melt at temperatures above 4000 K. There are no measurements of the steady-state rate of the reverse process, i.e., diamond nucleation from the melt, because experiments are difficult at these extreme temperatures and pressures. Using numerical simulations, we estimate the diamond

  10. 9 CFR 311.6 - Diamond-skin disease.

    Science.gov (United States)

    2010-01-01

    ... 9 Animals and Animal Products 2 2010-01-01 2010-01-01 false Diamond-skin disease. 311.6 Section... CERTIFICATION DISPOSAL OF DISEASED OR OTHERWISE ADULTERATED CARCASSES AND PARTS § 311.6 Diamond-skin disease. Carcasses of hogs affected with diamond-skin disease when localized and not associated with systemic change...

  11. Organizing the un-organized? Evidence from Indian diamond industry

    NARCIS (Netherlands)

    Kaveti, Indu

    2014-01-01

    The Indian diamond industry is composed of tens of thousands of firms engaged in cutting and polishing of diamonds and resides in the so-called un-organized sector. However, together, these firms produce 11 out of 12 diamonds set in jewelery worldwide. In absence of formal systems of governance, how

  12. Local structure of liquid carbon controls diamond nucleation

    NARCIS (Netherlands)

    Ghiringhelli, L.M.; Valeriani, C.; Meijer, E.J.; Frenkel, D.

    2009-01-01

    Diamonds melt at temperatures above 4000 K. There are no measurements of the steady-state rate of the reverse process: diamond nucleation from the melt, because experiments are difficult at these extreme temperatures and pressures. Using numerical simulations, we estimate the diamond nucleation rate

  13. Performance of diamond detectors for VUV applications

    Science.gov (United States)

    BenMoussa, A.; Theissen, A.; Scholze, F.; Hochedez, J. F.; Schühle, U.; Schmutz, W.; Haenen, K.; Stockman, Y.; Soltani, A.; McMullin, D.; Vest, R. E.; Kroth, U.; Laubis, C.; Richter, M.; Mortet, V.; Gissot, S.; Delouille, V.; Dominique, M.; Koller, S.; Halain, J. P.; Remes, Z.; Petersen, R.; D'Olieslaeger, M.; Defise, J.-M.

    2006-11-01

    We report on experimental results with photodetectors made of diamond. the Large Yield Radiometer (LYRA), will use such detectors for the first time for a solar physics space instrument. A (LYRA) set of measurement campaigns was carried out to obtain their XUV-to-VIS characterization (responsivity, linearity, stability, homogeneity). The responsivity has been measured from the XUV to the NIR, in the wavelength range 1-1127 nm (i.e. 1240-1.1 eV). The diamond detectors exhibit a photoresponse varying in the 40-75 mA/W range at 7 nm and demonstrate a visible rejection ratio (200 versus 500 nm) larger than four orders of magnitude. We show that diamond photodetectors are sensitive sensors for VUV photons, stable within a few percent, with a good linearity and moderate homogeneity.

  14. Performance of diamond detectors for VUV applications

    Energy Technology Data Exchange (ETDEWEB)

    BenMoussa, A. [Royal Observatory of Belgium, Circular Avenue 3, B-1180 Brussels (Belgium)]. E-mail: ali.benmoussa@oma.be; Theissen, A.; Hochedez, J.F.; Gissot, S.; Delouille, V.; Dominique, M. [Royal Observatory of Belgium, Circular Avenue 3, B-1180 Brussels (Belgium); Scholze, F. [Physikalisch-Technische Bundesanstalt (PTB), Abbestr. 2-12, D-10587 Berlin (Germany); Schuehle, U. [Max-Planck-Institut fuer Sonnensystemforschung, D-37191 Katlenburg-Lindau (Germany); Schmutz, W. [Physikalisch-Meteorologisches Observatorium Davos, World Radiation Center, CH-7260 Davos Dorf (Switzerland); Haenen, K.; D' Olieslaeger, M. [Institute for Materials Research, Limburgs Universitair Centrum, Wetenschapspark 1, B-3590 Diepenbeek (Belgium)]|[Division IMOMEC, IMEC vzw, Wetenschapspark 1, B-3590 Diepenbeek (Belgium); Stockman, Y. [Centre Spatial de Liege, Av. Pre Aily B-4031 Angleur (Belgium); Soltani, A. [Institut d' Electronique, de Microelectronique et de Nanotechnologie (IEMN) F-59652 Villeneuve d' Ascq (France); McMullin, D. [Naval Research Laboratory (NRL), 4555 Overlook Avenue, S.W., Washington, DC 20375 (United States); Vest, R.E. [National Institute of Standards and Technology (NIST), 100 Bureau Drive, Gaithersburg, MD 20899 (United States); Kroth, U.; Laubis, C.; Richter, M. [Physikalisch-Technische Bundesanstalt (PTB), Abbestr. 2-12, D-10587 Berlin (Germany); Mortet, V. [Institute for Materials Research, Limburgs Universitair Centrum, Wetenschapspark 1, B-3590 Diepenbeek (Belgium); Koller, S. [Physikalisch-Meteorologisches Observatorium Davos, World Radiation Center, CH-7260 Davos Dorf (Switzerland); Halain, J.P; Defise, J.-M. [Centre Spatial de Liege, Av. Pre Aily B-4031 Angleur (Belgium); Remes, Z. [Institute for Materials Research, Limburgs Universitair Centrum, Wetenschapspark 1, B-3590 Diepenbeek (Belgium); Petersen, R. [Division IMOMEC, IMEC vzw, Wetenschapspark 1, B-3590 Diepenbeek (Belgium)

    2006-11-30

    We report on experimental results with photodetectors made of diamond. the Large Yield Radiometer (LYRA), will use such detectors for the first time for a solar physics space instrument. A (LYRA) set of measurement campaigns was carried out to obtain their XUV-to-VIS characterization (responsivity, linearity, stability, homogeneity). The responsivity has been measured from the XUV to the NIR, in the wavelength range 1-1127 nm (i.e. 1240-1.1 eV). The diamond detectors exhibit a photoresponse varying in the 40-75 mA/W range at 7 nm and demonstrate a visible rejection ratio (200 versus 500 nm) larger than four orders of magnitude. We show that diamond photodetectors are sensitive sensors for VUV photons, stable within a few percent, with a good linearity and moderate homogeneity.

  15. Radiometric characteristics of new diamond PIN photodiodes

    Science.gov (United States)

    Ben Moussa, A.; Schühle, U.; Scholze, F.; Kroth, U.; Haenen, K.; Saito, T.; Campos, J.; Koizumi, S.; Laubis, C.; Richter, M.; Mortet, V.; Theissen, A.; Hochedez, J. F.

    2006-04-01

    New PIN photodiode devices based on CVD diamond have been produced showing high responsivity in a narrow bandpass around 200 nm. A set of measurement campaigns was carried out to obtain their XUV-to-VIS characterization (responsivity, stability, linearity, homogeneity). The responsivity has been measured from the XUV to the NIR, in the wavelength range of 1 nm to 1127 nm (i.e. 1240 to 1.1 eV). The diamond detectors exhibit a high responsivity of 10 to 30 mA W-1 around 200 nm and demonstrate a visible rejection ratio (200 nm versus 500 nm) of six orders of magnitude. We show that these PIN diamond photodiodes are sensitive sensors in the 200 to 220 nm range, stable under brief irradiation with a good linearity and homogeneity. They will be used for the first time in a solar physics space instrument LYRA, the Large Yield RAdiometer.

  16. Photoluminescent properties of single crystal diamond microneedles

    Science.gov (United States)

    Malykhin, Sergey A.; Ismagilov, Rinat R.; Tuyakova, Feruza T.; Obraztsova, Ekaterina A.; Fedotov, Pavel V.; Ermakova, Anna; Siyushev, Petr; Katamadze, Konstantin G.; Jelezko, Fedor; Rakovich, Yury P.; Obraztsov, Alexander N.

    2018-01-01

    Single crystal needle-like diamonds shaped as rectangular pyramids were produced by combination of chemical vapor deposition and selective oxidation with dimensions and geometrical characteristics depending on the deposition process parameters. Photoluminescence spectra and their dependencies on wavelength of excitation radiation reveal presence of nitrogen- and silicon-vacancy color centers in the diamond crystallites. Photoluminescence spectra, intensity mapping, and fluorescence lifetime imaging microscopy indicate that silicon-vacancy centers are concentrated at the crystallites apex while nitrogen-vacancy centers are distributed over the whole crystallite. Dependence of the photoluminescence on excitation radiation intensity demonstrates saturation and allows estimation of the color centers density. The combination of structural parameters, geometry and photoluminescent characteristics are prospective for advantageous applications of these diamond crystallites in quantum information processing and optical sensing.

  17. 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).

  18. Chemistry and physics of diamond surfaces

    CERN Document Server

    Domke, A

    1999-01-01

    in the literature. The valence band of diamond is investigated by off-normal ARUPS. The features observed are consistent with possible transitions, which are determined using bulk band structure calculations and comparison with the experimental binding energies. This thesis is concerned with the chemistry and physics of C(100) surfaces of diamond. The polished and cleaned C(100) surface is examined by surface microscopy (Atomic-force Microscopy), electron diffraction (Low-energy Electron Diffraction) and photoemission (X-ray Photoelectron Spectroscopy and Ultra-violet Photoelectron Spectroscopy). Results are presented on the presence of oxygen, nitrogen and hydrogen/deuterium on the C(100) surface. Finally, the valence band structure of diamond is probed by angle-resolved photoemission. We have confirmed by AFM that the grooves from the soft polishing process are present on a polished C(100) surface and found sporadic traces of hard polish on a surface polished in the soft polishing direction. XPS studies hav...

  19. CVD diamond detectors for ionizing radiation

    CERN Document Server

    Friedl, M; Bauer, C; Berfermann, 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; 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; Pernegger, H; Pernicka, Manfred; Peitz, A; Pirollo, S; Polesello, P; Pretzl, Klaus P; 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; Vittone, E; Walsh, A M; Wedenig, R; Weilhammer, Peter; Ziock, H J; Zöller, M

    1999-01-01

    In future HEP accelerators, such as the LHC (CERN), detectors and electronics in the vertex region of the experiments will suffer from extreme radiation. Thus radiation hardness is required for both detectors and electronics to survive in this harsh environment. CVD diamond, which is investigated by the RD42 Collaboration at CERN, can meet these requirements. Samples of up to 2*4 cm/sup 2/ have been grown and refined for better charge collection properties, which are measured with a beta source or in a test beam. A large number of diamond samples has been irradiated with hadrons to fluences of up to 5*10/sup 15/ cm/sup -2/ to study the effects of radiation. Both strip and pixel detectors were prepared in various geometries. Samples with strip metallization have been tested with both slow and fast readout electronics, and the first diamond pixel detector proved fully functional with LHC electronics. (16 refs).

  20. Conductivity and superconductivity in heavily vacant diamond

    Directory of Open Access Journals (Sweden)

    S A Jafari

    2009-08-01

    Full Text Available   Motivated by the idea of impurity band superconductivity in heavily Boron doped diamond, we investigate the doping of various elements into diamond to address the question, which impurity band can offer a better DOS at the Fermi level. Surprisingly, we find that the vacancy does the best job in producing the largest DOS at the Fermi surface. To investigate the effect of disorder in Anderson localization of the resulting impurity band, we use a simple tight-binding model. Our preliminary study based on the kernel polynomial method shows that the impurity band is already localized at the concentration of 10-3. Around the vacancy concentration of 0.006 the whole spectrum of diamond becomes localized and quantum percolation takes place. Therefore to achieve conducting bands at concentrations on the scale of 5-10 percent, one needs to introduce correlations such as hopping among the vacancies .

  1. Combining lake and watershed characteristics with Landsat TM data for remote estimation of regional lake clarity

    Science.gov (United States)

    McCullough, Ian M.; Loftin, Cyndy; Sader, Steven A.

    2012-01-01

    Water clarity is a reliable indicator of lake productivity and an ideal metric of regional water quality. Clarity is an indicator of other water quality variables including chlorophyll-a, total phosphorus and trophic status; however, unlike these metrics, clarity can be accurately and efficiently estimated remotely on a regional scale. Remote sensing is useful in regions containing a large number of lakes that are cost prohibitive to monitor regularly using traditional field methods. Field-assessed lakes generally are easily accessible and may represent a spatially irregular, non-random sample of a region. We developed a remote monitoring program for Maine lakes >8 ha (1511 lakes) to supplement existing field monitoring programs. We combined Landsat 5 Thematic Mapper (TM) and Landsat 7 Enhanced Thematic Mapper Plus (ETM+) brightness values for TM bands 1 (blue) and 3 (red) to estimate water clarity (secchi disk depth) during 1990–2010. Although similar procedures have been applied to Minnesota and Wisconsin lakes, neither state incorporates physical lake variables or watershed characteristics that potentially affect clarity into their models. Average lake depth consistently improved model fitness, and the proportion of wetland area in lake watersheds also explained variability in clarity in some cases. Nine regression models predicted water clarity (R2 = 0.69–0.90) during 1990–2010, with separate models for eastern (TM path 11; four models) and western Maine (TM path 12; five models that captured differences in topography and landscape disturbance. Average absolute difference between model-estimated and observed secchi depth ranged 0.65–1.03 m. Eutrophic and mesotrophic lakes consistently were estimated more accurately than oligotrophic lakes. Our results show that TM bands 1 and 3 can be used to estimate regional lake water clarity outside the Great Lakes Region and that the accuracy of estimates is improved with additional model variables that reflect

  2. 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

  3. Deep Mantle Fluids Bottled Up in Diamonds

    Science.gov (United States)

    Weiss, Y.; Pearson, D. G.

    2015-12-01

    Many mantle xenoliths and mineral inclusions in diamonds reflect refertilisation and enrichment by mantle metasomatism, a key mechanism for controlling abrupt changes in the chemical and physical properties of the continental lithospheric mantle (CLM) globally. However, the nature of the fluids involved can normally only be constrained indirectly from geochemical proxies or calculated using mineral/melt partition coefficients. Direct samples of mantle metasomatic fluids, shielded from any late stage alteration, are encased as microinclusions in fast-growing diamonds - "fibrous diamonds". These trapped high-density fluids (HDFs) provide a unique chemical and physical record for tracing the sources of deep mantle fluids and constraining the processes that shape their nature.Diamond HDFs vary between four major compositional types: saline, silicic and high-Mg plus low-Mg carbonatitic. A strong connection has been established between high-Mg carbonatitic HDFs and a carbonated peridotite source. In addition, the silicic and low-Mg carbonatitic HDFs have been related to hydrous eclogite (±carbonate). However, the compositionally extreme saline fluid endmember remained enigmatic and its source in the deep lithosphere has remained ambiguous. Our new data on fluid-rich diamonds show the geochemical fingerprints of a subducting slab as the source of deep mantle fluids of saline composition. In addition, for the first time, we show that these deep saline fluids are parental, via fluid rock interaction, to in-situ forming carbonatitic and silicic melts in the lithosphere. This model provides a strong platform for resolving the effects of the compositional spectrum of mantle fluids, which alter the deep lithosphere globally and play key roles in diamond formation.

  4. Nanocrystalline diamond films for biomedical applications

    DEFF Research Database (Denmark)

    Pennisi, Cristian Pablo; Alcaide, Maria

    2014-01-01

    resistance, chemical inertness, superior electrochemical behavior, biocompatibility, and nontoxicity. These properties have positioned the nanocrystalline diamond films as an attractive class of materials for a range of therapeutic and diagnostic applications in the biomedical field. Consequently...... 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......, it is envisioned that the application of this unique class of materials will significantly influence the next generation of biomedical devices....

  5. Selected Bibliography II-Diamond Surface Chemistry

    Science.gov (United States)

    1993-09-30

    Hiraki A., Kawarada H. and Nishimura K. TITLE: "Cleaning of Surfaces of Crystalline Materials" JNL: Jpn. Kokai Tokkyo Koho REF: (1989) AUTHOR: Kimock F. M...Lett. REF: 58 (1991) 819 AUTHOR: Mori Y., I1awazadd H. an%4 hiraki A. TITLE: "Properties of Metal/Diamond Interfaces and Effects of Oxygen Adsorbed...Homoepitaxial Diamond Films by Atomic Force Microscopy" JNL: Appl. Phys. Lett. REF: 60 (1992) 1685 AUTHOR: Mori Y., Eimori N., Ma J.S., Ito T. and Hiraki A

  6. Progress of Diamond-like Carbon Films

    Directory of Open Access Journals (Sweden)

    CHEN Qing-yun

    2017-03-01

    Full Text Available Diamond-like carbon(DLC films had many unique and outstanding properties such as high thermal conductivity, high hardness, excellent chemical inertness, low friction coefficients and wear coefficients. The properties and combinations were very promising for heat sink, micro-electromechanical devices, radiation hardening, biomedical devices, automotive industry and other technical applications, more research and a lot of attention were attracted in recent years. The research progress of diamond-like films and the nucleation mechanism of film were summarized, and application prospect of DLC films were demonstrated. The aim of this paper is to provide insights on the research trend of DLC films and the industry applications.

  7. STM/STS study of superconducting diamond

    Directory of Open Access Journals (Sweden)

    Alexey Troyanovskiy, Terukazu Nishizaki and Evgeniy Ekimov

    2006-01-01

    Full Text Available We present a scanning tunneling microscopy/spectroscopy (STM/STS study of synthetic polycrystalline boron-doped diamond in the temperature range 0.5–4.3 K. At 4.3 K the sample-surface was very non-uniform and tunneling I(V spectra were typical for p-type semiconductors. After cooling below the superconducting transition temperature, we detected and measured the superconducting gap of diamonds. At temperatures around 0.5 K the energy gap was around 0.8 and 1 mV (for two different samples.

  8. Case study and lessons learned for the Great Lakes ITS Program, Airport ITS Integration and the Road Infrastructure Management System projects, final report, Wayne County, Michigan

    Science.gov (United States)

    2007-03-02

    This report presents the case study and lessons learned for the national evaluation of the Great Lakes Intelligent Transportation Systems (GLITS) Airport ITS Integration and Road Infrastructure Management System (RIMS) projects. The Airport ITS Integ...

  9. The surface properties of nanocrystalline diamond and nanoparticulate diamond powder and their suitability as cell growth support surfaces

    NARCIS (Netherlands)

    Lechleitner, Thomas; Klauser, Frederik; Seppi, Thomas; Lechner, Judith; Jennings, Paul; Perco, Paul; Mayer, Bernd; Steinmüller-Nethl, Doris; Preiner, Johannes; Hinterdorfer, Peter; Hermann, Martin; Bertel, Erminald; Pfaller, Kristian; Pfaller, Walter

    2008-01-01

    Nanocrystalline diamond (NCD) films and nanoparticulate diamond powder (DP) are the two main representatives of diamond at the nanoscale. This study was designed to investigate the suitability of these biomaterials as cell growth supports and to determine surface characteristic properties best

  10. Diamond-NICAM-SPRINTARS: downscaling and simulation results

    Science.gov (United States)

    Uchida, J.

    2012-12-01

    As a part of initiative "Research Program on Climate Change Adaptation" (RECCA) which investigates how predicted large-scale climate change may affect a local weather, and further examines possible atmospheric hazards that cities may encounter due to such a climate change, thus to guide policy makers on implementing new environmental measures, a "Development of Seamless Chemical AssimiLation System and its Application for Atmospheric Environmental Materials" (SALSA) project is funded by the Japanese Ministry of Education, Culture, Sports, Science and Technology and is focused on creating a regional (local) scale assimilation system that can accurately recreate and predict a transport of carbon dioxide and other air pollutants. In this study, a regional model of the next generation global cloud-resolving model NICAM (Non-hydrostatic ICosahedral Atmospheric Model) (Tomita and Satoh, 2004) is used and ran together with a transport model SPRINTARS (Spectral Radiation Transport Model for Aerosol Species) (Takemura et al, 2000) and a chemical transport model CHASER (Sudo et al, 2002) to simulate aerosols across urban cities (over a Kanto region including metropolitan Tokyo). The presentation will mainly be on a "Diamond-NICAM" (Figure 1), a regional climate model version of the global climate model NICAM, and its dynamical downscaling methodologies. Originally, a global NICAM can be described as twenty identical equilateral triangular-shaped panels covering the entire globe where grid points are at the corners of those panels, and to increase a resolution (called a "global-level" in NICAM), additional points are added at the middle of existing two adjacent points, so a number of panels increases by fourfold with an increment of one global-level. On the other hand, a Diamond-NICAM only uses two of those initial triangular-shaped panels, thus only covers part of the globe. In addition, NICAM uses an adaptive mesh scheme and its grid size can gradually decrease, as the grid

  11. Bathymetry of Lake Michigan

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Bathymetry of Lake Michigan has been compiled as a component of a NOAA project to rescue Great Lakes lake floor geological and geophysical data and make it more...

  12. Bathymetry of Lake Huron

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Bathymetry of Lake Huron has been compiled as a component of a NOAA project to rescue Great Lakes lake floor geological and geophysical data and make it more...

  13. Bathymetry of Lake Ontario

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Bathymetry of Lake Ontario has been compiled as a component of a NOAA project to rescue Great Lakes lake floor geological and geophysical data and make it more...

  14. Great Lakes Bathymetry

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Bathymetry of Lakes Michigan, Erie, Saint Clair, Ontario and Huron has been compiled as a component of a NOAA project to rescue Great Lakes lake floor geological and...

  15. Bathymetry of Lake Superior

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Bathymetry of Lake Superior has been compiled as a component of a NOAA project to rescue Great Lakes lake floor geological and geophysical data and make it more...

  16. Great Lakes CoastWatch Node

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — CoastWatch is a nationwide National Oceanic and Atmospheric Administration (NOAA) program within which the Great Lakes Environmental Research Laboratory (GLERL)...

  17. 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.

  18. Fabrication of freestanding heteroepitaxial diamond substrate via micropatterns and microneedles

    Science.gov (United States)

    Aida, Hideo; Kim, Seong-Woo; Ikejiri, Kenjiro; Kawamata, Yuki; Koyama, Koji; Kodama, Hideyuki; Sawabe, Atsuhito

    2016-03-01

    The fabrication of a high-quality freestanding diamond substrate was successfully demonstrated via heteroepitaxy by introducing diamond micropatterns and microneedles in the early stage of growth. Micropatterns contributed to a marked reduction in the number of dislocations induced by epitaxial lateral overgrowth, and microneedles relaxed heteroepitaxial strain. Raman spectroscopy indicated the absence of nondiamond carbon inclusions in the obtained freestanding substrate. The full width at half maximum of the X-ray rocking curve for diamond (004) reflections was 0.07°, the lowest value for heteroepitaxial diamond that has been reported so far. The results provide novel insights toward realizing large-diameter single-crystalline diamond substrates.

  19. Water Resources Research program: nearshore currents and water temperatures in southwestern Lake Michigan. Progress report, June--December 1975

    Energy Technology Data Exchange (ETDEWEB)

    Saunders, K.D.; Van Loon, L.S.

    1976-05-01

    Nearshore currents and water temperatures were measured almost continuously from June 23 through December 22, at five moorings in an array centered 4 km offshore of south Chicago. The mooring array was square, each side 1.6 km long. A current-meter mooring was placed at each corner, with one mooring in the center. One Bendix Q-15 current meter and one YSI temperature sensor were fixed to each mooring line. Each meter and associated temperature sensor was placed at middepth; the water depth averaged about 12 m. The following types of graphs are presented for current and wind observations: (1) U, V flow components versus time, (2) specific kinetic energy versus time, (3) flow speeds and directions versus time, (4) composite velocity histograms and associated U, V-component histograms, and (5) progressive-vector diagrams. Also presented are listings of the component programs used to reduce the data. Currents in the region were dominantly shore-parallel. Water temperatures reflected several episodes of upwelling and downwelling. Detailed analyses of the data will be presented in subsequent reports.

  20. 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

  1. 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.

  2. Noble gases in presolar diamonds I: Three distinct components and their implications for diamond origins

    Science.gov (United States)

    Huss, Gary R.; Lewis, Roy S.

    1994-01-01

    High-purity separates of presolar diamond were prepared from 14 primitive chondrites from 7 compositional groups. Their noble gases were measured using stepped pyrolysis. Three distinct noble gas components are present in diamonds, HL, P3, and P6, each of which is found to consist of five noble gases. P3, released between 200 C and 900 C, has a 'planetary' elemental abundance pattern and roughly 'normal' isotopic ratios. HL, consisting of isotopically anomalous Xe-HL and Kr-H, Ar with high Ar-38/Ar-36, and most of the gas making up Ne-A2 and He-A, is released between 1100 C and 1600 C. HL has 'planetary' elemental ratios, except that it has much more He and Ne than other known 'planetary' components. HL gases are carried in the bulk diamonds, not in some trace phase. P6 has a slightly higher median release temperature than HL and is not cleanly separated from HL by stepped pyrolysis. Our data suggest that P6 has roughly 'normal' isotopic compositions and 'planetary' elemental ratios. Both P3 and P6 seem to be isotopically distinct from P1, the dominant 'planetary' noble-gas component in primitive chondrites. Release characteristics suggest that HL and P6 are sited in different carriers within the diamond fractions, while P3 may be sited near the surfaces of the diamonds. We find no evidence of separability of Xe-H and Xe-L or other isotopic variations in the HL component. However, because approximately 10(exp 10) diamonds are required to measure a Xe composition, a lack of isotopic variability does not constrain diamonds to come from a single source. In fact, the high abundance of diamonds in primitive chondrites and the presence of at least three distinct noble-gas components strongly suggest that diamonds originated in many sources. Relative abundances of noble-gas components in diamonds correlate with degree of thermal processing, indicating that all meteorites sampled essentially the same mixture of diamonds. That mixture was probably inherited from the Sun

  3. Great Lakes Science Center

    Data.gov (United States)

    Federal Laboratory Consortium — Since 1927, Great Lakes Science Center (GLSC) research has provided critical information for the sound management of Great Lakes fish populations and other important...

  4. Shock-wave micron-size diamond synthesis from fullerenes

    Energy Technology Data Exchange (ETDEWEB)

    Epanchintsev, O.G.; Zubchenko, A.S.; Kobelev, N.N. [Federal Scientific Center, Moscow (Russian Federation)] [and others

    1995-12-31

    Shock-wave synthesis of micron-size diamond is performed from fullerenes C{sub 60} -- C {sub 150} powders using the explosive compaction technique with plane shock-wave loading at different pressures in the range of 24-40 GPa. The compacts of different initial compositions consisted of diamond, fcc fullerite C{sub 60}, graphite and amorphous carbon. The most coarse diamond grains sized up to 6 {mu}n were formed at the shock pressure of 24 and 40 GPa in the compacts of initial powder mixture copper-5 mass.% fullerite and at shock pressure of 40 GPa in the compact of initial powder mixture copper - 10 mass.% fullerite. Shock-wave synthesis of diamond is performed without forming intermediate diamond-like phases, such as n-diamond and lonsdaleite (hexagonal diamond) in the final products.

  5. 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 .

  6. Diamond and Cubic Boron Nitride: Properties, Growth and Applications

    Science.gov (United States)

    Soltani, A.; Talbi, A.; Mortet, V.; BenMoussa, A.; Zhang, W. J.; Gerbedoen, J.-C.; De Jaeger, J.-C.; Gokarna, A.; Haenen, K.; Wagner, P.

    2010-11-01

    Since their first synthesis, cubic boron nitride (c-BN) and diamond thin films have triggered a vivid interest in these wide band gap materials for many different applications. Because of superior properties, c-BN and diamond can be applied in optic, electronic and acoustic for high performances devices. In this discussion, we first describe briefly the properties of c-BN and diamond and we review both the growth techniques and the progresses achieved in the synthesis of c-BN and diamond, and in a second part, characteristics of new c-BN and diamond UV detectors for solar observation are reported. These photo-detectors present extremely low dark current, high breakdown voltage, high responsivity and stability under UV irradiation. Finally, diamond based acoustic devices and sensors are presented. High frequency acoustic wave devices can be design for high frequency filtering or sensing applications. Diamond/AlN micro-cantilevers are excellent platform for sensor applications.

  7. Effect of diamond nucleation process on propagation losses of AlN/diamond SAW filter.

    Science.gov (United States)

    Elmazria, Omar; El Hakiki, Mohamed; Mortet, Vincent; Assouar, Badreddine M; Nesládek, Milos; Vanecek, Milan; Bergonzo, Philippe; Alnot, Patrick

    2004-12-01

    In this work, the effect of a diamond nucleation process on freestanding aluminium nitride (AlN)/diamond surface acoustic wave (SAW) device performances was studied. Before diamond deposition, silicon (Si) substrates have been mechanically nucleated, using an ultrasonic vibration table with submicron diamond slurry, and bias-enhanced nucleated (BEN). Freestanding diamond layers obtained on mechanically scratched Si substrates exhibit a surface roughness of R(MS) = 13 nm, whereas very low surface roughness (as low as R(MS) < or = 1 nm) can be achieved on a freestanding BEN diamond layer. Propagation losses have been measured as a function of the operating frequency for the two nucleation techniques. Dispersion curves of phase velocities and electromechanical coupling coefficient (K2) were determined experimentally and by calculation as a function of normalized thickness AlN film (kh(AlN) = 2pi h(AlN)/lambda). Experimental results show that the propagation losses strongly depend on the nucleation technique, and that these losses are weakly increased with frequency when the BEN technique is used.

  8. Blood diamonds and non-state actors

    National Research Council Canada - National Science Library

    Smillie, Ian

    2013-01-01

    ...) Diamonds, however, were central to the funding of the most brutal and protracted wars in a generation. In Angola, Uniao Nacional para a Independencia Total de Angola (UNITA), thwarted in the run-up to independence in 1974, fought a brutal war against the government for almost two decades thereafter. Almost half a million people died, and half the ...

  9. Application of diamond based beam loss monitors

    Energy Technology Data Exchange (ETDEWEB)

    Hempel, Maria [Brandenburgische Technische Univ. Cottbus (Germany); DESY, Zeuthen (Germany); CERN, Geneva (Switzerland); Baer, Tobias [CERN, Geneva (Switzerland); Hamburg Univ. (Germany); Castro Carballo, Elena Maria [DESY, Zeuthen (Germany); Lohmann, Wolfgang [Brandenburgische Technische Univ. Cottbus (Germany); DESY, Zeuthen (Germany); Schmidt, Ruediger [CERN, Geneva (Switzerland)

    2013-07-01

    The LHC has an operational stored energy of 130MJ per beam. Only a small percentage of beam losses in the LHC equipment can damage material or lead to magnet quenches. Therefore, it is important to monitor different types of beam losses, e.g. scattering on residual gas particles, UFOs, collisions and injection losses. A detailed understanding of beam loss mechanisms is necessary to reduce them and ensure save operation. Two different beam loss monitors are installed in the LHC tunnel: ionization chambers and diamond sensors. Ionization chambers trigger a beam dump if beam losses exceed a certain threshold. They have a time resolution of 40um (half LHC turn) which is not sufficient to resolve bunch-by-bunch beam losses. Diamond sensors have a nanosecond time resolution and can therefore detect bunch-by-bunch beam losses. This time resolution allows an analysis of various types of beam losses and an understanding of the mechanisms. For the first time beam loss intensities were measured bunch-by-bunch caused by different origins of losses. Beam loss measurements using diamond sensors will be presented. The results are compared to simulations and good qualitative agreement was found. The potential of diamond sensors for LHC and experiment applications are discussed.

  10. Diamond structures grown from polymer composite nanofibers

    Czech Academy of Sciences Publication Activity Database

    Potocký, Štěpán; Kromka, Alexander; Babchenko, Oleg; Rezek, Bohuslav; Martinová, L.; Pokorný, P.

    2013-01-01

    Roč. 5, č. 6 (2013), s. 519-521 ISSN 2164-6627 R&D Projects: GA ČR GAP108/12/0910; GA ČR GAP205/12/0908 Institutional support: RVO:68378271 Keywords : chemical vapour deposition * composite polymer * nanocrystalline diamond * nanofiber sheet * SEM Subject RIV: BM - Solid Matter Physics ; Magnetism

  11. On-Chip Diamond Raman Laser

    CERN Document Server

    Latawiec, Pawel; Burek, Michael J; Hausmann, Birgit J M; Bulu, Irfan; Loncar, Marko

    2015-01-01

    Synthetic single-crystal diamond has recently emerged as a promising platform for Raman lasers at exotic wavelengths due to its giant Raman shift, large transparency window and excellent thermal properties yielding a greatly enhanced figure-of-merit compared to conventional materials. To date, diamond Raman lasers have been realized using bulk plates placed inside macroscopic cavities, requiring careful alignment and resulting in high threshold powers (~W-kW). Here we demonstrate an on-chip Raman laser based on fully-integrated, high quality-factor, diamond racetrack micro-resonators embedded in silica. Pumping at telecom wavelengths, we show Stokes output discretely tunable over a ~100nm bandwidth around 2-{\\mu}m with output powers >250 {\\mu}W, extending the functionality of diamond Raman lasers to an interesting wavelength range at the edge of the mid-infrared spectrum. Continuous-wave operation with only ~85 mW pump threshold power in the feeding waveguide is demonstrated along with continuous, mode-hop-fr...

  12. High vacuum tribology of polycrystalline diamond coatings

    Indian Academy of Sciences (India)

    Coating surfaces with PCD offers exciting possibilities of substantially reducing the wear and possibly the friction of the critical moving mechanical assemblies. There are several mechanisms of friction proposed by different authors for diamond films. Gardos (1994, 1999) through his research over decades has proposed that ...

  13. Diamond Light Source: status and perspectives.

    Science.gov (United States)

    Materlik, Gerhard; Rayment, Trevor; Stuart, David I

    2015-03-06

    Diamond Light Source, a third-generation synchrotron radiation (SR) facility in the UK, celebrated its 10th anniversary in 2012. A private limited company was set up in April 2002 to plan, construct and operate the new user-oriented SR facility, called in brief Diamond. It succeeded the Synchrotron Radiation Source in Daresbury, a second-generation synchrotron that opened in 1980 as the world's first dedicated X-ray-providing facility, closing finally in 2008, by which time Diamond's accelerators and first beamlines were operating and user experiments were under way. This theme issue of Philosophical Transactions of the Royal Society A gives some examples of the rich diversity of research done in the initial five years, with some glimpses of activity up to 2014. Speakers at the 10 year anniversary symposium were drawn from a small number of major thematic areas and each theme was elaborated by a few speakers whose contributions were placed into a broader context by a leading member of the UK academic community in the role of rapporteur. This introduction gives a summary of the design choices and strategic planning of Diamond as a coherent user facility, a snapshot of its present status and some consideration of future perspectives. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

  14. Raman spectroscopic investigation of graphitization of diamond during spark plasma sintering of UO{sub 2}-diamond composite nuclear fuel

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Zhichao [Mechanical and Aerospace Engineering, University of Florida, Gainesville, FL, 32611 (United States); Subhash, Ghatu, E-mail: subhash@ufl.edu [Mechanical and Aerospace Engineering, University of Florida, Gainesville, FL, 32611 (United States); Tulenko, James S. [Materials Science and Engineering, University of Florida, Gainesville, FL, 32611 (United States)

    2016-07-15

    Micro-Raman spectroscopy (MRS) was utilized to investigate the graphitization of diamond particles within a UO{sub 2}-diamond composite processed by spark plasma sintering (SPS). While pure diamond gives a sharp Raman peak at 1331.6 cm{sup −1}, the graphitized diamond shows broad peaks either at 1350 cm{sup −1} (G-peak) or 1580 cm{sup −1} (D-peak). The degree of graphitization was quantified by calculating the area beneath the diamond and graphite peaks. It was found that more than 20% of diamond was graphitized on the surface of the UO{sub 2}-diamond pellet and only around 10% diamond was graphitized in the interior regions of the pellet. This current study highlights the necessity to review the implications of these results carefully while implementing UO{sub 2}-diamond composite nuclear fuel. - Highlights: • Characterized the phase transformation of diamond in UO{sub 2}-diamond composite fuel. • Quantified the degree of graphitization using Raman spectroscopy. • Discussed the effect of spark plasma sintering on the graphitization.

  15. The Influence of Volcanological and Sedimentological Processes on Diamond Grade Distribution: Examples From the Ekati Diamond Mine, NWT, Canada

    Science.gov (United States)

    Porritt, L. A.; Cas, R. A.; Ailleres, L.; Oshust, P.

    2009-05-01

    The study of the diamond distribution within two kimberlite pipes, Fox and Koala, from the Ekati Diamond Mine, NWT, Canada, in conjunction with detailed facies models has shown several distinct relationships of deposit type and grade distribution. In both pipes the lithological facies represent grade units which can be distinguished from each other in terms of relative size and abundance of diamonds. Positive correlation of olivine grain size and abundance with diamond grade is seen, indicating that density sorting of fragmental kimberlites occurs both in pyroclastic and resedimented deposits. Though surface geological processes do not control the diamond potential of the erupting magma, they can be responsible for concentrating diamonds into economically significant proportions. A good understanding of the eruption, transport and depositional processes responsible for the individual lithological units and the diamond distribution within them is important for successful resource estimation and may lead to recognition of areas suitable for selective mining, making a marginal deposit economic.

  16. Stable isotope evolution and paleolimnology of ancient Lake Creede

    Science.gov (United States)

    Rye, Robert O.; Bethke, Philip M.; Finkelstein, David B.

    2000-01-01

    The lacustrine carbonate and travertine (tufa) deposits of ancient Lake Creede preserve a remarkable record of the isotopic evolution of the lake. That record indicates that the δ18O of the lake water, and by analogy its salinity, evolved through evaporation. Limited and less reliable data on hydrous minerals and fluid inclusions in early diagenetic carbonates indicate that the δD of the lake waters also evolved through evaporation. The isotope data place restrictions on models of the physical limnology of the lake and its evolution.The closed-basin Lake Creede formed shortly after collapse of the 26.9 Ma Creede caldera. Throughout most of its history it occupied the northern three quarters of the moat between the resurgent dome and wall of the caldera. The Creede Formation was deposited in the basin, dominantly as lacustrine sediments. Travertine mounds interfinger with Creede Formation sediments along the inner and outer margins of the lake basin. An estimated one-half of the original thickness of the Creede Formation has been lost mainly to erosion although scattered remnants of the upper portion remain on the caldera walls. Two diamond core holes (CCM-1 and CCM-2) sampled the uneroded portion of the Creede Formation as part of the U.S. Continental Drilling Program. Volcaniclastic material, including tuff units deposited directly into the lake and ash washed in from the watershed, compose the main lithologies of the Creede Formation. These volcaniclastic strata were produced by episodic ring-fracture volcanism.Lacustrine carbonates make up about 15% of the section sampled by drill core. They occur as 1 mm to 2 cm low-Mg calcite laminae alternating with siliciclastic laminae in scattered intervals throughout the preserved section. The carbonate laminae are accumulations of 5–20 µm crystallites (microsparites) and brine shrimp fecal pellets (peloids) composed mainly of microsparite particles. Low-Mg calcite also occurs as an early diagenetic replacement of

  17. 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.

  18. Investigation of landscape and lake acidification relationships

    Energy Technology Data Exchange (ETDEWEB)

    Rush, R.M.; Honea, R.B.; Krug, E.C.; Peplies, R.W.; Dobson, J.E.; Baxter, F.P.

    1985-10-01

    This interim report presents the rationale and initial results for a program designed to gather and analyze information essential to a better understanding of lake acidification in the northeastern United States. The literature pertinent to a study of landscape and lake acidification relationships is reviewed and presented as the rationale for a landscape/lake acidification study. The results of a study of Emmons Pond in northwestern Connecticut are described and lead to the conclusion that a landscape change was a contributor to the acidification of this pond. A regional study of sixteen lakes in southern New England using Landsat imagery is described, and preliminary observations from a similar study in the Adirondack Mountains are given. These results indicate that satellite imagery can be useful in identifying types of ground cover important to landscape/lake acidification relationships.

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

    Science.gov (United States)

    Wang, Tao; Zhuang, Hao; Jiang, Xin

    2015-12-01

    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 (Co2Si, 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.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2004-01-30

    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 {mu}m 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.

  1. 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.

  2. Limnology of Eifel maar lakes

    National Research Council Canada - National Science Library

    Scharf, Burkhard W; Björk, Sven

    1992-01-01

    ... & morphometry - Physical & chemical characteristics - Calcite precipitation & solution in Lake Laacher See - Investigations using sediment traps in Lake Gemundener Maar - Phytoplankton of Lake Weinfelder Maar...

  3. Coastal Change Analysis Program (C-CAP) Great Lakes; Michigan 1996-2001 era land cover change analysis (NODC Accession 0042189)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set is a change analysis of 1996-era C-CAP land cover and 2001-era C-CAP land cover for the State of Michigan, in the Great Lakes Region of the U.S. This...

  4. National Program for Inspection of Non-Federal Dams. Crystal Lake Dam (CT 00138), Lower Connecticut River Basin, Middletown, Connecticut. Phase I Inspection Report.

    Science.gov (United States)

    1980-01-01

    than 2’ from the foundation, and each :. pie ." is keyed to its neighbor will reduce the piping liability along the rock contact. *"A11 parts of the... plano and ecifications for the proposed dam at Crystal Lake. Hr. Uelti has just returned from Switterland where he has spent a year study- Lng the

  5. National Dam Safety Program. Loon Lake Dam (Inventory Number NY-795), Upper Hudson River Basin, Warren County, New York. Phase I Inspection Report,

    Science.gov (United States)

    1980-07-01

    the level of Loon Lake for recreational purposes. 2 *~~~~1*~ - --7 g. Design and Construction History The plan included in this report indicates that... bulders an. .sz𔄀vQ1..d.1.. e. d._ ...n...iuteral Q’ .ardpan r~ttp - resistant ..t.o..ersj. ! l-.o . -..--..ar n...1.mp ..oua

  6. WORKSHOP ON THE CHARACTERIZATION, MODELING, REMEDIATION AND MONITORING OF MINING-IMPACTED PIT LAKES, SANDS RGENCY CASINO HOTEL, DOWNTOWN RENO, NV. APRIL 4-6, 2000 (PROGRAM FLYER)

    Science.gov (United States)

    The purpose of this workshop is to provide a forum for the exchange of scientific infomation on current approaches for assessing the characterization, monitoring, treatment and/or remediation of impacts on aquatic ecosystems including pit lakes from mining-related contamination i...

  7. 78 FR 46569 - Diamond Sawblades and Parts Thereof From the Republic of Korea: Final Results of Antidumping Duty...

    Science.gov (United States)

    2013-08-01

    ... Diamond Industrial Co., Ltd 0.00 Hyosung Diamond Industrial Co., Ltd, Western Diamond Tools 120.90 Inc., and Hyosung D&P Co., Ltd Shinhan Diamond Industrial Co., Ltd. and SH Trading, Inc. 0.00 (collectively...

  8. 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.

  9. Specific Internal Structure of Diamonds from Zarnitsa Kimberlite Pipe

    Directory of Open Access Journals (Sweden)

    Alexey Ragozin

    2017-05-01

    Full Text Available The Zarnitsa kimberlite pipe is one of the largest pipes of the Yakutian diamondiferous province. Currently, some limited published data exists on the diamonds from this deposit. Among the diamond population of this pipe there is a specific series of dark gray to black diamonds with transition morphologies between octahedron and rounded rhombic dodecahedron. These diamonds have specific zonal and sectorial mosaic-block internal structures. The inner parts of these crystals have polycrystalline structure with significant misorientations between sub-individuals. The high consistency of the mechanical admixtures (inclusions in the diamonds cores can cause a high grid stress of the crystal structure and promote the block (polycrystalline structure of the core components. These diamond crystals have subsequently been formed due to crystallization of bigger sub-individuals on the polycrystalline cores according to the geometric selection law.

  10. Nucleation, growth and acoustic properties of thin film diamond

    CERN Document Server

    Whitfield, M D

    1999-01-01

    emission spectroscopy has been used to study the influence of substrate bias on the microwave plasma during diamond nucleation. Surface acoustic wave (SAW) devices have recently emerged as promising near term applications for currently available CVD diamond however little is known about the propagation of acoustic waves in this material; a detailed study of the influence of film characteristics on acoustic propagation in free standing CVD diamond films has been undertaken using the techniques of laser ultrasonic analysis. The unusual combination of extreme properties possessed by diamond could benefit a wide range of applications. Thus far practical utilisation of this material has remained difficult and consequently limited; natural and synthetic crystals are unsuitable forms for many uses; particularly electronic applications which ideally require large area, single crystal substrates. Emerging CVD methods for the growth of thin film diamond offer a practical alternative; although nucleation on non-diamond ...

  11. Processing of Photonic Crystal Nanocavity for Quantum Information in Diamond

    CERN Document Server

    Bayn, Igal; Lahav, Alex; Salzman, Joseph; Kalish, Rafi; Fairchild, Barbara A; Prawer, Steven; Barth, Michael; Benson, Oliver; Wolf, Thomas; Siyushev, Petr; Jelezko, Fedor; Wrachtrup, Jorg

    2010-01-01

    The realization of photonic crystals (PC) in diamond is of major importance for the entire field of spintronics based on fluorescent centers in diamond. The processing steps for the case of diamond differ from those commonly used, due to the extreme chemical and mechanical properties of this material. The present work summarizes the state of the art in the realization of PC's in diamond. It is based on the creation of a free standing diamond membrane into which the desired nano-sized patterns are milled by the use of Focused-Ion-Beam (FIB). The optimal fabrication-oriented structure parameters are predicted by simulations. The milling strategies, the method of formation the diamond membrane, recipes for dielectric material-manipulation in FIB and optical characterization constraints are discussed in conjunction with their implication on PC cavity design. The thus produced structures are characterized via confocal photoluminescence.

  12. Topics in Nanophotonic Devices for Nitrogen-Vacancy Color Centers in Diamond

    Science.gov (United States)

    Babinec, Thomas Michael

    of this approach based on incorporation of NV centers in pure diamond via ion implantation. In chapter 4 we consider the optimal design of photonic devices offering both collection efficiency and cavity-enhancements and extend the model of the NV center to include photonic effects. In chapter 5 we briefly introduce a novel optically active spin discovered in a diamond nanowire. Finally, in chapter 6 we conclude with several proposals to extend this research program.

  13. Measurement of tool forces in diamond turning

    Energy Technology Data Exchange (ETDEWEB)

    Drescher, J.; Dow, T.A.

    1988-12-01

    A dynamometer has been designed and built to measure forces in diamond turning. The design includes a 3-component, piezoelectric transducer. Initial experiments with this dynamometer system included verification of its predicted dynamic characteristics as well as a detailed study of cutting parameters. Many cutting experiments have been conducted on OFHC Copper and 6061-T6 Aluminum. Tests have involved investigation of velocity effects, and the effects of depth and feedrate on tool forces. Velocity has been determined to have negligible effects between 4 and 21 m/s. Forces generally increase with increasing depth of cut. Increasing feedrate does not necessarily lead to higher forces. Results suggest that a simple model may not be sufficient to describe the forces produced in the diamond turning process.

  14. Precision diamond grinding of ceramics and glass

    Energy Technology Data Exchange (ETDEWEB)

    Smith, S.; Paul, H.; Scattergood, R.O.

    1988-12-01

    A new research initiative will be undertaken to investigate the effect of machine parameters and material properties on precision diamond grinding of ceramics and glass. The critical grinding depth to initiate the plastic flow-to-brittle fracture regime will be directly measured using plunge-grind tests. This information will be correlated with machine parameters such as wheel bonding and diamond grain size. Multiaxis grinding tests will then be made to provide data more closely coupled with production technology. One important aspect of the material property studies involves measuring fracture toughness at the very short crack sizes commensurate with grinding damage. Short crack toughness value`s can be much less than the long-crack toughness values measured in conventional fracture tests.

  15. Effect of argon during diamond deposition

    Energy Technology Data Exchange (ETDEWEB)

    Barbosa, D.C.; Mengui, U.A.; Contin, A.; Trava-Airoldi, V.J.; Baldan, M.R.; Corat, E.J. [Instituto Nacional de Pesquisas Espaciais (INPE), Sao Jose dos Campos, SP (Brazil). Laboratorio Associado de Sensores e Materiais

    2014-07-01

    The effect of argon content upon the growth rate and the properties of diamond thin films grown with different grains sizes is explored. An argon-free and argon-rich gas mixture of methane and hydrogen is used in a hot filament chemical vapor deposition reactor. Characterization of the films is accomplished by scanning electron microscopy, Raman spectroscopy and high-resolution x-ray diffraction. An extensive comparison of the growth rate values obtained in this study with those found in the literature suggests that there are distinct common trends for microcrystalline and nanocrystalline diamond growth, despite a large variation in the gas mixture composition. Included is a discussion of the possible reasons for these observations. (author)

  16. New Diamond Color Center for Quantum Communication

    Science.gov (United States)

    Huang, Ding; Rose, Brendon; Tyryshkin, Alexei; Sangtawesin, Sorawis; Srinivasan, Srikanth; Twitchen, Daniel; Markham, Matthew; Edmonds, Andrew; Gali, Adam; Stacey, Alastair; Wang, Wuyi; D'Haenens-Johansson, Ulrika; Zaitsev, Alexandre; Lyon, Stephen; de Leon, Nathalie

    2017-04-01

    Color centers in diamond are attractive for quantum communication applications because of their long electron spin coherence times and efficient optical transitions. Previous demonstrations of color centers as solid-state spin qubits were primarily focused on centers that exhibit either long coherence times or highly efficient optical interfaces. Recently, we developed a method to stabilize the neutral charge state of silicon-vacancy center in diamond (SiV0) with high conversion efficiency. We observe spin relaxation times exceeding 1 minute and spin coherence times of 1 ms for SiV0 centers. Additionally, the SiV0 center also has > 90 % of its emission into its zero-phonon line and a narrow inhomogeneous optical linewidth. The combination of a long spin coherence time and efficient optical interface make the SiV0 center a promising candidate for applications in long distance quantum communication.

  17. Tunable continuous-wave diamond Raman laser.

    Science.gov (United States)

    Parrotta, Daniele C; Kemp, Alan J; Dawson, Martin D; Hastie, Jennifer E

    2011-11-21

    Continuous-wave operation of a diamond Raman laser, intracavity-pumped by a diode-pumped InGaAs semiconductor disk laser (SDL), is reported. The Raman laser, which utilized a 6.5-mm-long synthetic single-crystal diamond, reached threshold for 5.3 W of diode laser pump power absorbed by the SDL. Output power up to 1.3 W at the first Stokes wavelength of 1227 nm was demonstrated with excellent beam quality and optical conversion efficiency of 14.4% with respect to absorbed diode laser pump power. Broad tuning of the Raman laser output between 1217 and 1244 nm was achieved via intracavity tuning of the SDL oscillation wavelength. © 2011 Optical Society of America

  18. Surface Structure of Aerobically Oxidized Diamond Nanocrystals

    Science.gov (United States)

    2014-10-27

    films (2−100 nm grain size), this is the first observation in colloidal diamond nanocrystals.48 This signature is absent from previous NEXAFS studies...prior to aerobic oxidation as described above. HRTEM Characterization and in Situ Oxidation of HPHT Nanodiamonds. Colloidal dispersions of nanodia...for beam instability . Carbon K-edge NEXAFS spectra were collected at U7A in partial electron yield (PEY) mode using a grid bias of −200 V. Oxygen K

  19. Quantum Optics in Diamond Nanophotonic Chips

    Science.gov (United States)

    2014-07-01

    etching process that enables rapid nanocrystal creation across the entirety of a high-quality chemical vapor deposited (CVD) diamond substrate. High...responsivity of photodetection of 0.108 A/W, competitive with current non- avalanche Ge de- tectors for silicon photonics integration [17, 18]. Owing to...device. A bi-layer graphene is deposited on the waveguide. The light transmits along the waveguide and couples with the graphene effectively. Two Ti/Au

  20. Chemical vapor deposition of diamond films on patterned substrates

    OpenAIRE

    O.R. Monteiro

    2002-01-01

    The interest in using CVD diamond in the fabrication of microelectro-mechanical components has steadly increased over the last few years. Typical technology for manufacturing such components involve the molds patterned in silicon or silicon dioxide, which are filled by diamond deposition. The degree of conformality of the CVD film and the characteristics of the diamond-substrate interface becomes critical for the successful fabrication and performance of such devices. We have investigated the...

  1. 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.

  2. Lake Roosevelt Fisheries Monitoring Program; Measurement of Thyroxin Concentration as an Indicator of the Critical Period for Imprinting in the Kokanee Salmon (Orcorhynchus Nerka) Implications for Operating Lake Roosevelt Kokanee Hatcheries; 1991 Supplement Report.

    Energy Technology Data Exchange (ETDEWEB)

    Scholz, Allan T.; White, Ronald J.; Koehler, Valerie A. (Eastern Washington University, Upper Columbia United Tribes Fisheries Research Center, Cheney, WA)

    1992-05-01

    Previous investigations have determined that thyroid hormone surges activate olfactory imprinting in anadromous salmonid smolts. The mechanism of action appears to require binding of thyroid hormones to receptors in brain cell nuclei, which stimulates neuron differentiation and wires a pattern of neuron circuitry that allows for the permanent storage of the imprinted olfactory memory. In this study, thyroxine concentrations [T{sub 4}] were measured in 487 Lake Whatcom stock and 70 Lake Roosevelt stock Kokanee salmon to indicate the critical period for imprinting. Eggs, alevins and fry, reared at the Spokane Indian Kokanee Hatchery, were collected from January through August 1991. Sampled fish were flash frozen on dry ice and stored at {minus}80{degrees}C until T{sub 4} was extracted and concentrations determined by radioimmunassay. Mean concentration {+-} SEM of 10--20 individual fish (assayed in duplicate) were determined for each time period. T{sub 4} concentration peaked on the day of hatch at 16.8 ng/g body weight and again at swim-up at 16.0 {+-} 4.7 ng/g body weight. T{sub 4} concentration was 12.5 to 12.9 ng/g body weight in eggs, 7.1 to 15.2 ng/g body weight in. alevins, 4.5 to 11.4 ng/g body weight in 42 to 105 day old fry and 0.1 to 2.9 ng/g body weight in 112 to 185 day old fry. T{sub 4} concentrations were highest in eggs at 13.3 {+-} 2.8 ng/g body weight, then steadily decreased to 0.1 {+-} 0.1 ng/g body weight in older fry. Fry were released in Lake Roosevelt tributaries in July and August 1991, at about 170--180 days post hatching, in order to imprint them to those sites. The results of this study indicate that the time of release was not appropriate for imprinting. If T{sub 4} levels are an accurate guide for imprinting in kokanee, our results suggest that the critical period for imprinting in kokanee is at hatching or swim-up stages.

  3. Junction like behavior in polycrystalline diamond films

    Energy Technology Data Exchange (ETDEWEB)

    Bhaskaran, Shivakumar, E-mail: sbhaskar@mail.uh.edu [Department of Electrical and Computer Engineering, Cullen College of Engineering, University of Houston, TX 77004 (United States); Charlson, Earl Joe; Litvinov, Dmitri [Department of Electrical and Computer Engineering, Cullen College of Engineering, University of Houston, TX 77004 (United States); Makarenko, Boris [Department of Chemistry, University of Houston, TX 77004 (United States)

    2012-01-25

    Highlights: Black-Right-Pointing-Pointer The result that we obtained are compared with single crystalline diamond devices. Black-Right-Pointing-Pointer The barrier height of 4.4 eV matches the ideal pn-junction barrier height of diamond thin film. - Abstract: We have successfully fabricated polycrystalline diamond rectifying junction devices on n-type (1 0 0) silicon substrates by Hot Filament Chemical Vapor Deposition (HFCVD) using methane/hydrogen process gas and trimethyl borate and trimethyl phosphite dissolved in acetone as p- and n-type dopants, respectively. Impedance spectroscopy and current-voltage analysis indicates that the conduction is vertical down the grains and facets and not due to surface effects. Electrical characteristics were analyzed with In and Ti/Au top metal contacts with Al as the substrate contact. Current-voltage characteristics as a function of temperature showed barrier potentials of 1.1 eV and 0.77 eV for the In and Ti/Au contacts, respectively. Barrier heights of 4.8 eV (In) and 4.4 eV (Ti/Au) were obtained from capacitance-voltage measurements.

  4. TSC response of irradiated CVD diamond films

    CERN Document Server

    Borchi, E; Bucciolini, M; Guasti, A; Mazzocchi, S; Pirollo, S; Sciortino, S

    1999-01-01

    CVD diamond films have been irradiated with electrons, sup 6 sup 0 Co photons and protons in order to study the dose response to exposure to different particles and energies and to investigate linearity with dose. The Thermally Stimulated Current (TSC) has been studied as a function of the dose delivered to polymethilmetacrilate (PMMA) in the range from 1 to 12 Gy with 20 MeV electrons from a linear accelerator. The TSC spectrum has revealed the presence of two components with peak temperatures of about 470 and 520 K, corresponding to levels lying in the diamond band gap with activation energies of the order of 0.7 - 1 eV. After the subtraction of the exponential background the charge emitted during the heating scan has been evaluated and has been found to depend linearly on the dose. The thermally emitted charge of the CVD diamond films has also been studied using different particles. The samples have been irradiated with the same PMMA dose of about 2 Gy with 6 and 20 MeV electrons from a Linac, sup 6 sup 0 ...

  5. Benton Lake National Wildlife Refuge : Soil and Moisture Plan

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This Soil and Moisture Plan for Benton Lake NWR explains how the Soil and Moisture Program relates to Refuge objectives, outlines Program policies, and presents...

  6. Bathymetry of Lake Erie and Lake Saint Clair

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Bathymetry of Lake Erie and Lake Saint Clair has been compiled as a component of a NOAA project to rescue Great Lakes lake floor geological and geophysical data and...

  7. Lake Charles CCS Project

    Energy Technology Data Exchange (ETDEWEB)

    Leib, Thomas [Leucadia Energy, LLC, Salt Lake City, UT (United States); Cole, Dan [Denbury Onshore, LLC, Plano, TX (United States)

    2015-06-30

    , construction labor, engineering, and other costs. The CCS Project Final Technical Report is based on a Front End Engineering and Design (FEED) study prepared by SK E&C, completed in [June] 2014. Subsequently, Fluor Enterprises completed a FEED validation study in mid-September 2014. The design analyses indicated that the FEED package was sufficient and as expected. However, Fluor considered the construction risk based on a stick-build approach to be unacceptable, but construction risk would be substantially mitigated through utilization of modular construction where site labor and schedule uncertainty is minimized. Fluor’s estimate of the overall EPC project cost utilizing the revised construction plan was comparable to SKE&C’s value after reflecting Fluor’s assessment of project scope and risk characteristic. Development was halted upon conclusion of Phase 2A FEED and the project was not constructed.Transport and Sequestration – The overall objective of the pipeline project was to construct a pipeline to transport captured CO2 from the Lake Charles Clean Energy project to the existing Denbury Green Line and then to the Hastings Field in Southeast Texas to demonstrate effective geologic sequestration of captured CO2 through commercial EOR operations. The overall objective of the MVA portion of the project was to demonstrate effective geologic sequestration of captured CO2 through commercial Enhanced Oil Recovery (EOR) operations in order to evaluate costs, operational processes and technical performance. The DOE target for the project was to capture and implement a research MVA program to demonstrate the sequestration through EOR of approximately one million tons of CO2 per year as an integral component of commercial operations.

  8. Noble gases in diamonds - Occurrences of solarlike helium and neon

    Science.gov (United States)

    Honda, M.; Reynolds, J. H.; Roedder, E.; Epstein, S.

    1987-01-01

    Seventeen diamond samples from diverse locations were analyzed for the contents of He, Ar, Kr, and Xe, and of their isotopes, using a Reynolds (1956) type glass mass spectrometer. The results disclosed a large spread in the He-3/He-4 ratios, ranging from values below atmospheric to close to the solar ratio. In particular, solarlike He-3/He-4 ratios were seen for an Australian colorless diamond composite and an Arkansas diamond, which also displayed solarlike neon isotopic ratios. Wide variation was also observed in the He-4/Ar-40 ratios, suggesting a complex history for the source regions and the diamond crystallization processes.

  9. Ultrahydrophobicity of ZnO modified CVD diamond films

    Science.gov (United States)

    Yang, YiZhou; Wang, ChuanXi; Li, HongDong; Lin, Quan

    2013-04-01

    Chemical vapor deposited (CVD) polycrystalline diamond films with an ultrahydrophobic surface were fabricated by constructing a hierarchical structure through sputtering a ZnO layer on diamond grains, with a growth step feature. Under optimized conditions, the combined original diamond with a step structure of the ZnO can achieve a water contact angle (WCA) of as high as 141° ± 1°. It is proved that WCA decreases as the roughness of ZnO/PDF reduced. It can be concluded that the step structure of diamond grains and ZnO nuclei size have a great influence on the variation of WCA.

  10. 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.

  11. 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

  12. Carbon and nitrogen in Type 2 supernova diamonds

    Science.gov (United States)

    Clayton, Donald D.; Eleid, Mounib; Brown, Lawrence E.

    1993-03-01

    Abundant diamonds found in meteorites seem either to have condensed within supernova interiors during their expansions and coolings or to have been present around those explosions. Either alternative allows implantation of Xe-HL prior to interstellar mixing. A puzzling feature is the near normalcy of the carbon isotopes, considering that the only C-rich matter, the He-burning shell, is pure C-12 in that region. That last fact has caused many to associate supernova carbon with C-12 carbon, so that its SUNOCONS have been anticipated as very C-12-rich. We show that this expectation is misleading because the C-13-rich regions of Type 2's have been largely overlooked in this thinking. We here follow the idea that the diamonds nucleated in the C-12-rich He shell, the only C-rich site for nucleation, but then attached C-13-rich carbon during turbulent encounters with overlying C-13-rich matter. That is, the initial diamonds continued to grow during the same collisional encounters that cause the Xe-HL implantation. Instead of interacting with the small carbon mass having 13/12 = 0.2 in the upper He zone, however, we have calculated the remnants of the initial H-burning core, which left behind C-13-rich matter as it receded during core hydrogen burning. Howard et al. described why the velocity mixing would be essential to understanding the implantation of both the Xe-H and Xe-L components. Velocity mixing is now known to occur from the X-ray and gamma-ray light curves of supernova 1987A. Using the stellar evolution code developed at Goettingen, we calculated at Clemson the evolution of a grid of massive stars up to the beginning of core He burning. We paid attention to all H-burning reactions throughout the star, to the treatment of both convection and semiconvection, and to the recession of the outer boundary of the convective H-burning core as the star expands toward a larger redder state. This program was to generate a careful map of the CNO isotope distribution as He

  13. 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.

  14. Highly dispersible diamond nanoparticles for pretreatment of diamond films on Si substrate

    Science.gov (United States)

    Zhao, Shenjie; Huang, Jian; Zhou, Xinyu; Ren, Bing; Tang, Ke; Xi, Yifan; Wang, Lin; Wang, Linjun; Lu, Yicheng

    2018-03-01

    High quality diamond film on Si substrate was synthesized by coating diamond nanoparticles prepared by polyglycerol grafting (ND-PG) dispersion as pre-treatment method. Transmission electron microscope indicates that ND-PG is much more dispersible than untreated nanoparticles in organic solvents. The surface morphology was characterized by scanning electron microscope while atomic force microscope was conducted to measure the surface roughness. Microstructure properties were carried out by Raman spectroscopy and X-ray diffraction. The results revealed an increase in nucleation density, an acceleration of growth rate and an improvement of film crystalline quality by using spin-coating ND-PG pretreatment.

  15. Geophysical investigation of sentinel lakes in Lake, Seminole, Orange, and Volusia Counties, Florida

    Science.gov (United States)

    Reich, Christopher; Flocks, James; Davis, Jeffrey

    2012-01-01

    This study was initiated in cooperation with the St. Johns River Water Management District (SJRWMD) to investigate groundwater and surface-water interaction in designated sentinel lakes in central Florida. Sentinel lakes are a SJRWMD established set of priority water bodies (lakes) for which minimum flows and levels (MFLs) are determined. Understanding both the structure and lithology beneath these lakes can ultimately lead to a better understanding of the MFLs and why water levels fluctuate in certain lakes more so than in other lakes. These sentinel lakes have become important water bodies to use as water-fluctuation indicators in the SJRWMD Minimum Flows and Levels program and will be used to define long-term hydrologic and ecologic performance measures. Geologic control on lake hydrology remains poorly understood in this study area. Therefore, the U.S. Geological Survey investigated 16 of the 21 water bodies on the SJRWMD priority list. Geologic information was obtained by the tandem use of high-resolution seismic profiling (HRSP) and direct-current (DC) resistivity profiling to isolate both the geologic framework (structure) and composition (lithology). Previous HRSP surveys from various lakes in the study area have been successful in identifying karst features, such as subsidence sinkholes. However, by using this method only, it is difficult to image highly irregular or chaotic surfaces, such as collapse sinkholes. Resistivity profiling was used to complement HRSP by detecting porosity change within fractured or collapsed structures and increase the ability to fully characterize the subsurface. Lake Saunders (Lake County) is an example of a lake composed of a series of north-south-trending sinkholes that have joined to form one lake body. HRSP shows surface depressions and deformation in the substrate. Resistivity data likewise show areas in the southern part of the lake where resistivity shifts abruptly from approximately 400 ohm meters (ohm-m) along the

  16. Supplement Analysis for the Transmission System Vegetation Management Program FEIS (DOE/EIS-0285/SA-125 (Echo Lake-Maple Valley #1 [Mile 1-9], Adno 8258)

    Energy Technology Data Exchange (ETDEWEB)

    Shurtliff, Aaron [Bonneville Power Administration (BPA), Portland, OR (United States)

    2003-02-18

    Vegetation Management for portion of the Echo Lake – Maple Valley #1 500 kV transmission line located from tower structure 1/1 to 9/2. BPA proposes to clear targeted vegetation within the Right-of-Ways along access roads and around towers that may impede the operation and maintenance of the subject transmission lines. See Section 1.4 of the attached checklists for a complete description of the proposed action.

  17. Supplement Analysis for the Transmission System Vegetation Management Program FEIS (DOE/EIS-0285/SA-124 (Echo Lake-Maple Valley #1 [Mile 9-16], Adno 8258)

    Energy Technology Data Exchange (ETDEWEB)

    Shurtliff, Aaron [Bonneville Power Administration (BPA), Portland, OR (United States)

    2003-02-18

    Vegetation Management for portion of the Echo Lake – Maple Valley #1 500 kV transmission line located from tower structure 9/2 to 16/5. BPA proposes to clear targeted vegetation within the Right-of-Ways along access roads and around towers that may impede the operation and maintenance of the subject transmission lines. See Section 1.4 of the attached checklists for a complete description of the proposed action.

  18. Modeling of Diamond Field-Emitter-Arrays for high brightness photocathode applications

    Science.gov (United States)

    Kwan, Thomas; Huang, Chengkun; Piryatinski, Andrei; Lewellen, John; Nichols, Kimberly; Choi, Bo; Pavlenko, Vitaly; Shchegolkov, Dmitry; Nguyen, Dinh; Andrews, Heather; Simakov, Evgenya

    2017-10-01

    We propose to employ Diamond Field-Emitter-Arrays (DFEAs) as high-current-density ultra-low-emittance photocathodes for compact laser-driven dielectric accelerators capable of generating ultra-high brightness electron beams for advanced applications. We develop a semi-classical Monte-Carlo photoemission model for DFEAs that includes carriers' transport to the emitter surface and tunneling through the surface under external fields. The model accounts for the electronic structure size quantization affecting the transport and tunneling process within the sharp diamond tips. We compare this first principle model with other field emission models, such as the Child-Langmuir and Murphy-Good models. By further including effects of carrier photoexcitation, we perform simulations of the DFEAs' photoemission quantum yield and the emitted electron beam. Details of the theoretical model and validation against preliminary experimental data will be presented. Work ssupported by LDRD program at LANL.

  19. THERMAL STABILITY STUDY OF DIAMOND-LIKE CARBON FILMS CONTAINING CRYSTALLINE DIAMOND NANOPARTICLES

    Directory of Open Access Journals (Sweden)

    Beatriz Campos Ramos

    2014-08-01

    Full Text Available Nanocrystalline diamond (NCD particles are incorporated into diamond-like carbon (DLC films in order to prevent NCD-DLC electrochemical corrosion. In the current paper, the thermal stability of these films was investigated. The NCD-DLC films were deposited on 316L stainless steel substrates using plasma enhanced chemical vapor deposition. The grain size of the diamond crystallites and their concentration were varied in order to obtain different NCD-DLC films. The samples were annealed to 50°C for 1 h. The annealing temperature increased until the complete graphitization of the films (ramp of 50°C. Raman scattering spectroscopy was used to evaluate in detail the chemical structure of the DLC and NCD-DLC films. The atomic arrangements and graphitization level according to the increasing temperature are discussed. The influence of NCD particle sizes and concentration on NCD-DLC thermal stability are also discussed. The results showed that the presence of crystalline diamond particles increased the graphitization temperature, which permits the use of NCD-DLC films in high temperature environments.

  20. National Lakes Assessment Data

    Data.gov (United States)

    U.S. Environmental Protection Agency — The National Lakes Assessment (NLA) is a first-ever statistically-valid survey of the biological condition of lakes and reservoirs throughout the U.S. The U.S....

  1. DNR 24K Lakes

    Data.gov (United States)

    Minnesota Department of Natural Resources — Medium scale lake polygons derived from the National Wetlands Inventory (NWI) polygons and MnDOT Basemap lake delineations. Integrated with the DNR 24K Streams...

  2. The Great Lakes

    Science.gov (United States)

    The Great Lakes form the largest surface freshwater system on Earth. The U.S. and Canada work together to restore and protect the environment in the Great Lakes Basin. Top issues include contaminated sediments, water quality and invasive species.

  3. Pseudomorphic Stabilization of Diamond on Non-Diamond Substrates. Part 1. Diamond Grown on Single Crystal Beryllium Oxide. Part 2. Anomalous Band Gap Behavior and Phase Stability of c-BN/Diamond Alloys

    Science.gov (United States)

    1992-10-12

    at (I13, 2/3, 0) and 0 at (i/3, 2/3, 3/8) or vice versa. This structure (Table I) is geometrically similar to Lonsdaleite (hexagonal diamond) and thus...thin crystal of Lonsdaleite with the ABAB... stacking sequence can be achieved in the early stages of diamond growth.- 4 .25 After the elimination of the

  4. Diamond growth in premixed propylene-oxygen flames

    OpenAIRE

    Shin, Ho Seon; Goodwin, David G.

    1995-01-01

    Diamond film growth in low-pressure premixed propylene/oxygen flames is demonstrated. Well-faceted films are grown at a pressure of 180 Torr and a fuel/oxygen ratio of 0.47. Using propylene as the fuel may greatly improve the economics of flame synthesis of diamond, since propylene is an order of magnitude cheaper than acetylene.

  5. Single Crystal Diamond Needle as Point Electron Source

    Science.gov (United States)

    Kleshch, Victor I.; Purcell, Stephen T.; Obraztsov, Alexander N.

    2016-10-01

    Diamond has been considered to be one of the most attractive materials for cold-cathode applications during past two decades. However, its real application is hampered by the necessity to provide appropriate amount and transport of electrons to emitter surface which is usually achieved by using nanometer size or highly defective crystallites having much lower physical characteristics than the ideal diamond. Here, for the first time the use of single crystal diamond emitter with high aspect ratio as a point electron source is reported. Single crystal diamond needles were obtained by selective oxidation of polycrystalline diamond films produced by plasma enhanced chemical vapor deposition. Field emission currents and total electron energy distributions were measured for individual diamond needles as functions of extraction voltage and temperature. The needles demonstrate current saturation phenomenon and sensitivity of emission to temperature. The analysis of the voltage drops measured via electron energy analyzer shows that the conduction is provided by the surface of the diamond needles and is governed by Poole-Frenkel transport mechanism with characteristic trap energy of 0.2-0.3 eV. The temperature-sensitive FE characteristics of the diamond needles are of great interest for production of the point electron beam sources and sensors for vacuum electronics.

  6. Cell attachment on diamond-like carbon coating

    Indian Academy of Sciences (India)

    Home; Journals; Bulletin of Materials Science; Volume 25; Issue 1. Cell attachment on diamond-like carbon ... Preliminary results of diamond-like carbon (DLC) coating with its novel properties with no toxicity have caused a strong interest of commercial manufacturers of surgical implants. DLC coatings were prepared on ...

  7. 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.

  8. Diamond thin film temperature and heat-flux sensors

    Science.gov (United States)

    Aslam, M.; Yang, G. S.; Masood, A.; Fredricks, R.

    1995-01-01

    Diamond film temperature and heat-flux sensors are developed using a technology compatible with silicon integrated circuit processing. The technology involves diamond nucleation, patterning, doping, and metallization. Multi-sensor test chips were designed and fabricated to study the thermistor behavior. The minimum feature size (device width) for 1st and 2nd generation chips are 160 and 5 micron, respectively. The p-type diamond thermistors on the 1st generation test chip show temperature and response time ranges of 80-1270 K and 0.29-25 microseconds, respectively. An array of diamond thermistors, acting as heat flux sensors, was successfully fabricated on an oxidized Si rod with a diameter of 1 cm. Some problems were encountered in the patterning of the Pt/Ti ohmic contacts on the rod, due mainly to the surface roughness of the diamond film. The use of thermistors with a minimum width of 5 micron (to improve the spatial resolution of measurement) resulted in lithographic problems related to surface roughness of diamond films. We improved the mean surface roughness from 124 nm to 30 nm by using an ultra high nucleation density of 10(exp 11)/sq cm. To deposit thermistors with such small dimensions on a curved surface, a new 3-D diamond patterning technique is currently under development. This involves writing a diamond seed pattern directly on the curved surface by a computer-controlled nozzle.

  9. Diamonds in the Rough: Identifying and Serving Low Income Students

    Science.gov (United States)

    Ford, Donna Y.; Grantham, Tarek C.; Frazier-Trotman, Michelle

    2007-01-01

    Children who live in poverty are frequently at risk for underachievement. This is not to say that poverty automatically causes lack of achievement, but being poor can certainly take its toll. Gifted low income students can be compared to diamonds, which can only be formed under conditions of extreme heat and pressure. Both diamonds and…

  10. Hot-filament chemical vapour deposition of diamond onto steel

    NARCIS (Netherlands)

    Buijnsters, Ivan

    2003-01-01

    The main goal of this project was to establish the feasibility of depositing well adhering polycrystalline diamond coatings on steel substrates. It is well known that the growth and adhesion of diamond layers directly onto steels is complicated by the high carbon solubility and the high thermal

  11. Impurity impact ionization avalanche in p-type diamond

    Science.gov (United States)

    Mortet, V.; Soltani, A.

    2011-11-01

    Electrical conductivity of a highly boron doped chemical vapor deposited diamond thin film has been studied at different temperatures under high electric field conditions. Current-voltage characteristics have been measured using pulsed technique to reduce thermal effects. Experimental results evidence deep impurity impact ionization avalanche in p-type diamond up to room temperature.

  12. Development of diamond coated tool and its performance in ...

    Indian Academy of Sciences (India)

    ... could maintain low level of cutting forces and remarkably improved surface finish. It has been further revealed that success of the diamond coated tool depends primarily on adhesion of the diamond coating with the carbide substrate and this is strongly influenced by the pre-treatment of the carbide substrate surface before ...

  13. Distinctive glial and neuronal interfacing on nanocrystalline diamond.

    Directory of Open Access Journals (Sweden)

    Amel Bendali

    Full Text Available Direct electrode/neuron interfacing is a key challenge to achieve high resolution of neuronal stimulation required for visual prostheses. Neuronal interfacing on biomaterials commonly requires the presence of glial cells and/or protein coating. Nanocrystalline diamond is a highly mechanically stable biomaterial with a remarkably large potential window for the electrical stimulation of tissues. Using adult retinal cell cultures from rats, we found that glial cells and retinal neurons grew equally well on glass and nanocrystalline diamond. The use of a protein coating increased cell survival, particularly for glial cells. However, bipolar neurons appeared to grow even in direct contact with bare diamond. We investigated whether the presence of glial cells contributed to this direct neuron/diamond interface, by using purified adult retinal ganglion cells to seed diamond and glass surfaces with and without protein coatings. Surprisingly, these fully differentiated spiking neurons survived better on nanocrystalline diamond without any protein coating. This greater survival was indicated by larger cell numbers and the presence of longer neurites. When a protein pattern was drawn on diamond, neurons did not grow preferentially on the coated area, by contrast to their behavior on a patterned glass. This study highlights the interesting biocompatibility properties of nanocrystalline diamond, allowing direct neuronal interfacing, whereas a protein coating was required for glial cell growth.

  14. Influence of melt treatments and polished CVD diamond coated ...

    Indian Academy of Sciences (India)

    Performances of the turning inserts (uncoated and polished CVD diamond coated) were evaluated in machining Al–7Si and Al–7Si–2.5Cu cast alloys under dry environment using a lathe. The polished CVD diamond coated insert outperformed the uncoated cutting insert which suffered from sizeable edge buildup leading to ...

  15. Pitting corrosion behaviour of diamond coated tool steel

    NARCIS (Netherlands)

    Buijnsters, J.G.; Subba Rao, R.V.; Shankar, P.; Enckevort, W.J.P. van; Schermer, J.J.; Gebert, A.; Meulen, J.J. ter

    2005-01-01

    Using a hot filament chemical vapour deposition reactor, diamond films of approximately 2-3 mum in thickness were deposited on tool steel specimens with three different interlayer systems, namely CrN, Si and borided steel. The morphology, defect densities and residual stresses of the diamond films

  16. A Three-period Samuelson-Diamond Growth Model

    DEFF Research Database (Denmark)

    Blomgren-Hansen, Niels

    2005-01-01

    productive capital) has only one positive solution (r = n); however, this root is unstable. The Diamond model (no nonproductive abode of purchasing power) has also only one positive solution; the root is stable but inefficient. In a model with both productive capital and a non-productive abode of purchasing...... power, the inefficient Diamond solution becomes unstable and the socially optimal solution becomes stable....

  17. Mantle fluid evolution—a tale of one diamond

    Science.gov (United States)

    Klein-BenDavid, Ofra; Izraeli, Elad S.; Hauri, Erik; Navon, Oded

    2004-09-01

    Microinclusions analyzed in a coated diamond from the Diavik mine in Canada comprise peridotitic minerals and fluids. The fluids span a wide compositional range between a carbonatitic melt and brine. The diamond is concentrically zoned. The brine microinclusions reside in an inner growth zone and their endmember composition is K 19Na 25Ca 5Mg 8Fe 3Ba 2Si 4Cl 32 (mol%). The carbonatitic melt is found in an outer layer and its endmember composition is K 11Na 21Ca 11Mg 26Fe 7Ba 2Si 10Al 3P 2Cl 5. The transition in inclusion chemistry is accompanied by a change in the carbon isotopic composition of the diamond from -8.5‰ in the inner zone to -12.1‰ in the outer zone. We suggest that this transition reflects mixing between already evolved brine and a freshly introduced carbonatitic melt of different isotopic composition. The compositional range found in diamond ON-DVK-294 is the widest ever recorded in a single diamond. It closes the gap between brine found in cloudy octahedral diamonds from South Africa and carbonatitic melt analyzed in cubic diamonds from Zaire and Botswana. Thus, all microinclusions analyzed to date fall along two arrays connecting the carbonatitic melt composition to either a hydrous-silicic endmember or to a brine endmember. This connection suggests that many diamonds are formed from fluids derived form a mantle source not significantly influenced by local heterogeneities.

  18. Hard assets : The return of rare diamonds and gems

    NARCIS (Netherlands)

    Renneboog, Luc; Spaenjers, Christophe; Grynberg, Roman; Mbayi, Letsema

    This note examines the investment performance of diamonds and other gems (sapphires, rubies, and emeralds) over the period 1999–2010, using a novel data set of auction transactions. Over our time frame, the annualized real USD returns for white and colored diamonds equaled 6.4% and 2.9%,

  19. 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.

  20. Low resistance polycrystalline diamond thin films deposited by hot ...

    Indian Academy of Sciences (India)

    Administrator

    X-ray diffraction and Raman spectroscopy. The relationship between the diamond film growth rate and methane con- centration decreases the resistivity at various methane concentrations has been investigated and evaluated. 2. Experimental. Microcrystalline diamond films were deposited onto sili- con (Si) substrate using ...

  1. Hard Assets : The Returns on Rare Diamonds and Gems

    NARCIS (Netherlands)

    Renneboog, L.D.R.; Spaenjers, C.

    2011-01-01

    This paper examines the investment performance of diamonds and other gems (sapphires, rubies, and emeralds) over the period 1999-2010, using a novel data set of auction transactions. Between 1999 and 2010, the annualized real USD returns for white and colored diamonds equaled 6.4% and 2.9%,

  2. Nonlinear optical spectroscopy of diamond surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Chin, Rodney Peter [Univ. of California, Berkeley, CA (United States)

    1995-04-01

    Second harmonic generation (SHG) and infrared-visible sum frequency generation (SFG) spectroscopies have been shown to be powerful and versatile for studying surfaces with submonolayer sensitivity. They have been used in this work to study bare diamond surfaces and molecular adsorption on them. In particular, infrared-visible SFG as a surface vibrational spectroscopic technique has been employed to identify and monitor in-situ surface bonds and species on the diamond (111) surface. The CH stretch spectra allow us to investigate hydrogen adsorption, desorption, abstraction, and the nature of the hydrogen termination. The C(111) surface dosed with atomic hydrogen was found to be in a monohydride configuration with the hydrogen atoms situated at top-sites. The ratio of the abstraction rate to the adsorption rate was appreciable during atomic hydrogen dosing. Kinetic parameters for thermal desorption of H on C(111) were determined showing a near first-order kinetics. For the fully H-terminated (111) surface, a large (110 cm-1) anharmonicity and ~19 psec lifetime were measured for the first-excited CH stretch mode. The bare reconstructed C(111)-(2 x l) surface showed the presence of CC stretch modes which were consistent with the Pandey π-bonded chain structure. When exposed to the methyl radical, the SFG spectra of the C(111) surface showed features suggesting the presence of adsorbed methyl species. After heating to sufficiently high temperatures, they were converted into the monohydride species. Preliminary results on the hydrogen-terminated diamond (100) surface are also presented.

  3. A new tubular hot-wire CVD for diamond coating

    Science.gov (United States)

    Motahari, Hamid; Bellah, Samad Moemen; Malekfar, Rasoul

    2017-06-01

    A new tubular hot-wire chemical vapor deposition (HWCVD) system using a tubular quartz vacuum chamber has been fabricated. The filaments in this system can heat the substrate and act as a gas activator and thermally activator for gas species at the same time. The nano- and microcrystalline diamond coatings on the surface of steel AISI 316 substrates have been grown. To assess the results, SEM and FESEM images and Raman spectroscopy investigations have been applied. The results reveal that micro- and nanocrystalline diamond structures have been formed in the coatings, but the disordered diamond and some non-diamond phases, such as graphitic carbons, are also present in the coating layers. The analytical measurements show the growth of diamond films with well-faceted crystals in (111) direction. However, intrinsic stress, secondary nucleation, and poor adhesion are the main issues of future research for this new designed HWCVD.

  4. An on-chip diamond optical parametric oscillator

    CERN Document Server

    Hausmann, B J M; Venkataraman, V; Deotare, P; Loncar, M

    2013-01-01

    Efficient, on-chip optical nonlinear processes are of great interest for the development of compact, robust, low-power consuming systems for applications in spectroscopy, metrology, sensing and classical and quantum optical information processing. Diamond holds promise for these applications, owing to its exceptional properties. However, although significant progress has been made in the development of an integrated diamond photonics platform, optical nonlinearities in diamond have not been explored much apart from Raman processes in bulk samples. Here, we demonstrate optical parametric oscillations (OPO) via four wave mixing (FWM) in single crystal diamond (SCD) optical networks on-chip consisting of waveguide-coupled microring resonators. Threshold powers as low as 20mW are enabled by ultra-high quality factor (1*10^6) diamond ring resonators operating at telecom wavelengths, and up to 20 new wavelengths are generated from a single-frequency pump laser. We also report the inferred nonlinear refractive index...

  5. Is yne-diamond a super-hard material?

    Science.gov (United States)

    Bu, Hongxia; Zhao, Mingwen; Xi, Yan; Wang, Xiaopeng; Peng, Hua; Wang, Chunlei; Liu, Xiangdong

    2012-12-01

    Yne-diamond —a new carbon allotrope constructed by inserting two carbon atoms into the carbon-carbon bonds of diamond was expected to have super-hardness comparable to diamond because of the three-dimensional network of strong sp-sp3 and sp-sp bonds. However, from a theoretical point of view, this idea has never been validated carefully. Based on first-principles calculations, we present the first theoretical evidence that, in contrast to the early expectation, yne-diamond possesses low ideal tensile strength, low shear strength and small Pugh's modulus ratio, owning to the large void network in the covalent bond skeleton. Combined with a simple model, we predict that the yne-diamond family will not be a super-hard material family. This provides a new understanding of the mechanical properties of carbon allotropes containing sp-hybridized carbon atoms.

  6. Direct conversion of graphite into diamond through electronic excited states

    CERN Document Server

    Nakayama, H

    2003-01-01

    An ab initio total energy calculation has been performed for electronic excited states in diamond and rhombohedral graphite by the full-potential linearized augmented plane wave method within the framework of the local density approximation (LDA). First, calculations for the core-excited state in diamond have been performed to show that the ab initio calculations based on the LDA describe the wavefunctions in the electronic excited states as well as in the ground state quite well. Fairly good coincidence with both experimental data and theoretical prediction has been obtained for the lattice relaxation of the core exciton state. The results of the core exciton state are compared with nitrogen-doped diamond. Next, the structural stability of rhombohedral graphite has been investigated to examine the possibility of the transition into the diamond structure through electronic excited states. While maintaining the rhombohedral symmetry, rhombohedral graphite can be spontaneously transformed to cubic diamond. Tota...

  7. Crystal growth of CVD diamond and some of its peculiarities

    CERN Document Server

    Piekarczyk, W

    1999-01-01

    Experiments demonstrate that CVD diamond can form in gas environments that are carbon undersaturated with respect to diamond. This fact is, among others, the most serious violation of principles of chemical thermodynamics. In this $9 paper it is shown that none of the principles is broken when CVD diamond formation is considered not a physical process consisting in growth of crystals but a chemical process consisting in accretion of macro-molecules of polycyclic $9 saturated hydrocarbons belonging to the family of organic compounds the smallest representatives of which are adamantane, diamantane, triamantane and so forth. Since the polymantane macro-molecules are in every respect identical with $9 diamond single crystals with hydrogen-terminated surfaces, the accretion of polymantane macro- molecules is a process completely equivalent to the growth of diamond crystals. However, the accretion of macro-molecules must be $9 described in a way different from that used to describe the growth of crystals because so...

  8. Doping and cluster formation in diamond

    KAUST Repository

    Schwingenschlögl, Udo

    2011-09-09

    Introducing a cluster formation model, we provide a rational fundamental viewpoint for the difficulty to achieve n-type dopeddiamond. We argue that codoping is the way forward to form appropriately doped shallow regions in diamond and other forms of carbon such as graphene. The electronegativities of the codopants are an important design criterion for the donor atom to efficiently donate its electron. We propose that the nearest neighbour codopants should be of a considerably higher electronegativity compared to the donor atom. Codoping strategies should focus on phosphorous for which there are a number of appropriate codopants.

  9. Microscopy of nitride layers grown on diamond

    DEFF Research Database (Denmark)

    Pécz, B.; Tóth, L.; Barna, Á.

    2011-01-01

    are determined by selected area electron diffraction. Besides threading dislocations a high number of inversion domains (ID) were formed in some GaN films. The preparation of the diamond surface and the growth conditions proved to affect significantly the formation of crystal defects such as threading...... dislocations and IDs. Single polarity GaN films with a low density of dislocations were achieved for the optimized growth conditions. The highest quality GaN layers were grown on AlN buffer in which two crystalline variants were nucleated, but one of them was overgrown already in the thickness of the buffer...

  10. Diamond machine tool face lapping machine

    Science.gov (United States)

    Yetter, H.H.

    1985-05-06

    An apparatus for shaping, sharpening and polishing diamond-tipped single-point machine tools. The isolation of a rotating grinding wheel from its driving apparatus using an air bearing and causing the tool to be shaped, polished or sharpened to be moved across the surface of the grinding wheel so that it does not remain at one radius for more than a single rotation of the grinding wheel has been found to readily result in machine tools of a quality which can only be obtained by the most tedious and costly processing procedures, and previously unattainable by simple lapping techniques.

  11. Utilizing Centralized Diamond Architecture for Searching Algorithms

    Science.gov (United States)

    Damrudi, Masumeh; Jadidy Aval, Kamal

    2017-09-01

    Searching data elements and information in a fraction of time is still an important task for many areas of works. The importance of finding the best answer leads to use different algorithms which consume time. To improve the speed of searching information within mass information, employing parallel processing is inevitable. A search algorithm with constant time(CS) is proposed on centralized diamond architecture. We have optimized this algorithm to find the location and the number of occurrence of data, if there exists any.

  12. Lake Kariba, Zimbabwe

    African Journals Online (AJOL)

    1984-02-01

    Feb 1, 1984 ... Salisbury. COCHRANE, K.L. 1978. Seasonal fluctuations in the catches of Lim- nothrissa miodon (Boulenger) in Lake Kariba. Lake Kariba Fish. Res. Inst. Proj. Rept. 29: 1-163 (cyclostyled). DONNELLY, B.G. 1971. The fish population changes on Lake. Kariba between 1960 and 1968. Part I Cichlidae.

  13. Geophysical investigations of subglacial Antarctic lakes: identifying drill sites for lake access

    Science.gov (United States)

    Woodward, J.; Tulaczyk, S. M.; Smith, A.; Walter, J.; Ross, N.; Fricker, H. A.; Siegert, M. J.; Pettersson, R.; Thoma, M.; Corr, H.; King, E. C.; Vaughan, D.

    2009-12-01

    Subglacial lakes are regarded as viable habitats for novel microbial life forms and may contain sedimentary palaeo-environmental records which would provide critical insights into the glacial history of Antarctica. In-situ sampling and analysis is the only way to explore these lake environments. In order to successfully plan access programs detailed geophysical investigations, in particular seismic measurements of water depth, are required to identify suitable drill sites. Prior to the austral summer of 2006/07 measurements of water depths only existed for Subglacial Lake Vostok, and spatial coverage was limited due to the size of the lake. More recently, active source seismic experiments have been carried out over three subglacial lakes, South Pole Lake, Subglacial Lake Ellsworth (SLE) and Subglacial Lake Whillans (SLW). With drilling programs now funded for SLW (access planned for 2011/12) and SLE (access planned for 2012/13) we present results from the geophysical experiments at SLE and SLW to allow the identification of primary drill sites. The two lakes are very different. Geophysical results from SLE suggest that the lake is over 155 m deep and has been a stable system for much of the Holocene. We propose that in order to optimize the chances of successful access and sampling, the entry site should be located in an area with a melting interface near the centre of the lake where water depths are in the order of 100 m. This is away from the down-lake end which shows a higher possibility for basal freezing, with the consequent risk to equipment deployment and retrieval. In contrast, SLW is characterized by dynamic filling and draining over short (2-3 year periods) and most likely has a shallow water column (currently estimated to be in the order of 5-10 m). We suggest that the most suitable location for access will be the centre of the elevation change anomaly recorded over the lake. This point is near equidistant from the lake shoreline features identified from

  14. Perfluorooctane sulfonate (PFOS) contamination of fish in urban lakes: a prioritization methodology for lake management.

    Science.gov (United States)

    Xiao, Feng; Gulliver, John S; Simcik, Matt F

    2013-12-15

    The contamination of urban lakes by anthropogenic pollutants such as perfluorooctane sulfonate (PFOS) is a worldwide environmental problem. Large-scale, long-term monitoring of urban lakes requires careful prioritization of available resources, focusing efforts on potentially impaired lakes. Herein, a database of PFOS concentrations in 304 fish caught from 28 urban lakes was used for development of an urban-lake prioritization framework by means of exploratory data analysis (EDA) with the aid of a geographical information system. The prioritization scheme consists of three main tiers: preliminary classification, carried out by hierarchical cluster analysis; predictor screening, fulfilled by a regression tree method; and model development by means of a neural network. The predictive performance of the newly developed model was assessed using a training/validation splitting method and determined by an external validation set. The application of the model in the U.S. state of Minnesota identified 40 urban lakes that may contain elevated levels of PFOS; these lakes were not previously considered in PFOS monitoring programs. The model results also highlight ongoing industrial/commercial activities as a principal determinant of PFOS pollution in urban lakes, and suggest vehicular traffic as an important source and surface runoff as a primary pollution carrier. In addition, the EDA approach was further compared to a spatial interpolation method (kriging), and their advantages and disadvantages were discussed. Copyright © 2013 Elsevier Ltd. All rights reserved.

  15. National Dam Safety Program. Lake Anne Dam (Inventory Number VA 05909), Potomac River Basin, Fairfax County, Virginia. Phase I Inspection Report.

    Science.gov (United States)

    1980-07-01

    left2 abutment. Wiehle Avenue, a four-lane highway, runs along the crest of the dam. A macadam path runs along the berm on the upstream slope...adequate cover of grass. NAME OF DAM: LAKE ANNE DAM 13 The junctions of the embankment and abutments are composed of vegetated earth. There is grouted ...rprap to El 327 where the Macadam path is located, it actually appears that the top of riprap is about 2 feet below the surface of the path (See Photo

  16. National Dam Safety Program. Lake Arrowhead Dam (Inventory Number VA 17908), Potomac River Basin, Stafford County, Virginia. Phase I Inspection Report.

    Science.gov (United States)

    1980-07-01

    Grouted riprap may be necessary. A trash rack should be installed on the principal spillway riser. The driftwood in the pool below the principal...and side slopes ofI 8.5 H:lV and 2.5H:lV on the left and right sides, respectively. The control section is located on a two-lane macadam road which...two-lane macadam road which provid-es access to the residences around Lake Arrowhead runs along the dam crest; a similar road runs along the crest of

  17. National Dam Safety Program. Gwenmil Lake Dam (MO 31210), Upper Mississippi - Kaskaskia - St. Louis, Basin, Jefferson County, Missouri. Phase I Inspection Report.

    Science.gov (United States)

    1981-04-01

    NUMBER 2. GOVT ACCESSION NO 3. RECIPIENT’S CATALOG NUMBER 4. TITLE (aod Subtitle) -T "yPE OF REA.z & BERIOD COVEREO Phase I Dam Inspection Report...magnitude of the spillway design flu-1 for the Gwenmil Lake Dam, which, according to Table 1 of the guidelines, is clissified as small in size; is...specified, according to Table 3 of the quideliines for a dam of significant hazard potential and small size, to be a minimum of the 100-year frequency flood

  18. Michigan lakes: An assessment of water quality

    Science.gov (United States)

    Minnerick, R.J.

    2004-01-01

    Michigan has more than 11,000 inland lakes, that provide countless recreational opportunities and are an important resource that makes tourism and recreation a $15-billion-dollar per-year industry in the State (Stynes, 2002). Knowledge of the water-quality characteristics of inland lakes is essential for the current and future management of these resources.Historically the U. S. Geological Survey (USGS) and the Michigan Department of Environmental Quality (MDEQ) jointly have monitored water quality in Michigan's lakes and rivers. During the 1990's, however, funding for surface-water-quality monitoring was reduced greatly. In 1998, the citizens of Michigan passed the Clean Michigan Initiative to clean up, protect, and enhance Michigan's environmental infrastructure. Because of expanding water-quality-data needs, the MDEQ and the USGS jointly redesigned and implemented the Lake Water-Quality Assessment (LWQA) Monitoring Program (Michigan Department of Environmental Quality, 1997).

  19. Pleistocene lake level changes in Western Mongolia

    Science.gov (United States)

    Borodavko, P. S.

    2009-04-01

    .Petersburg, Nauka, 304 p. 4. Tarasov, P.E., Harrison, S.P., Saarse, L., Pushenko, M.Ya., Andreev, A.A., Aleshinskaya, Z.V., Davydova, N.N., Dorofeyuk, N.I., Efremov, Yu.V., Khomutova, V.I., Sevastyanov, D.V., Tamosaitis, J., Dorofeyuk, N.I., Efremov, Yu.V., Khomutova, V.I., Sevastyanov, D.V., Tamosaitis, J.,Uspenskaya, O.N., Yakushko, O.F. and Tarasova, I.V., 1994. Lake status records from the Former Soviet Union and Mongolia: Data Base Documentation, World Data Center -A for Paleoclimatology NOAA Paleoclimatology Program, Paleoclimatology Publications Series Report No 2, Boulder, Colorado USA, 274 p. 5. Tserensodnom, Zh., 1971. Mongol orny Nuur. Ulaanbaatar, TUAH, 202 p. 6. Vipper, P., Dorofeyuk, N., Liiva, A., Meteltseva, E., and Sokolovskaya, V., 1981. Palaeogeography of the Central Mongolia during the upper Pleistocene and Holocene. Izv. Akad. Nauk ESSR, Ser. Biol., vol. 30, no. 1, pp. 74-82.

  20. Adherent diamond film deposited on Cu substrate by carbon transport from nanodiamond buried under Pt interlayer

    Energy Technology Data Exchange (ETDEWEB)

    Liu Xuezhang [School of Materials Science and Engineering, Central South University, Changsha, 410083 (China); Wei Qiuping, E-mail: qiupwei@csu.edu.cn [School of Materials Science and Engineering, Central South University, Changsha, 410083 (China); State Key Laboratory of Powder Metallurgy, Central South University, Changsha, 410083 (China); Yu Zhiming, E-mail: zhiming@csu.edu.cn [School of Materials Science and Engineering, Central South University, Changsha, 410083 (China); State Key Laboratory of Powder Metallurgy, Central South University, Changsha, 410083 (China); Yang Taiming; Zhai Hao [School of Materials Science and Engineering, Central South University, Changsha, 410083 (China)

    2013-01-15

    Highlights: Black-Right-Pointing-Pointer Adherent polycrystalline diamond films were grown on copper substrate by carbon transport. Black-Right-Pointing-Pointer The nucleation density was increased to 10{sup 11} cm{sup -2}. Black-Right-Pointing-Pointer Diamond films were a composite structure of nano-crystalline diamond layer and micro-crystalline diamond layer. Black-Right-Pointing-Pointer Diamond nucleation was based by carbon dissolving from UDDs to Pt interlayer and formation of sp{sup 3}-bonded diamond clusters at the Pt surface. - Abstract: Diamond film deposited on Cu suffered from poor adhesion mainly due to the large mismatch of thermal expansion coefficients and the lack of affinity between carbon and Cu. Enhancing diamond nucleation by carbon transport from buried nanodiamond through a Pt ultrathin interlayer, adherent diamond film was then deposited on Cu substrate without distinctly metallic interlayer. This novel nucleation mechanism increased diamond nucleation density to 10{sup 11} cm{sup -2}, and developed diamond film with a composite structure of nano-crystalline diamond (NCD) layer and micro-crystalline diamond layer. Diamond film was characterized by the scanning electron microscope (SEM) and Raman spectroscope, respectively. The composition of diamond film/Cu substrate interface was examined by electron probe microanalysis (EPMA). The adhesion of diamond film was evaluated by indentation test. Those results show that a Pt ultrathin interlayer provides stronger chemically bonded interfaces and improve film adhesion.

  1. Cosmogenic Helium In Alluvial Diamonds From Namaqualand, South Africa

    Science.gov (United States)

    Burgess, R.; Harris, J. W.

    2005-12-01

    The interpretation of He in diamonds is not straightforward, potential sources include trapped mantle-derived He, radiogenic 4He, and 3He produced in situ by cosmic-ray spallation. The presence of cosmogenic 3He is manifested by high 3He/4He values and ratios of >200 Ra have been measured. 3He contents can be used to distinguish pipe from alluvial diamonds and the time interval that they have been involved in the sedimentary cycle, i.e. their surface exposure history. This is important information for locating the source of alluvial diamonds, understanding their transport histories and may provide a useful tool for diamond exploration. In this study we are analysing the He composition of ten alluvial diamonds from the Koignass-Namaqualand area along the south-west coast of South Africa and Namibia. Diamonds are currently mined at a depth of 100m below the surface from deposits of gravel beaches and river channels. Helium is extracted from the diamonds using a newly developed high temperature filament furnace having a blank approximately 200x lower than conventional resistance furnaces. The low blank of this system means it is possible to extract He by stepwise heating of diamonds weighing 0.05 g. Helium isotopes were analysed using a mass spectrometer with a 3He detection limit of 2,000,000 atoms equivalent to about 20 ka of surface exposure. Results from one diamond from Namaqualand illustrate the range of data obtained so far. This diamond was analysed using eight temperature steps and shows an overall increase in 3He/4He value with temperature from 8.8 x 10-6 to 2.6 x 10-2, the latter being only 10x lower than the pure spallogenic ratio. The cosmogenic 3He content is estimated at 73.5 x 10-12 cm3/g which is at the upper end of the range determined previously in alluvial diamonds from west African sources. Assuming a sea level 3He production rate at 30°S, then the 3He content of this diamond is equivalent to 16 Ma of surface exposure. Most of this exposure is

  2. Cluster Ion Implantation in Graphite and Diamond

    DEFF Research Database (Denmark)

    Popok, Vladimir

    2014-01-01

    Cluster ion beam technique is a versatile tool which can be used for controllable formation of nanosize objects as well as modification and processing of surfaces and shallow layers on an atomic scale. The current paper present an overview and analysis of data obtained on a few sets of graphite a...... implantation. Implantation of cobalt and argon clusters into two different allotropic forms of carbon, namely, graphite and diamond is analysed and compared in order to approach universal theory of cluster stopping in matter.......Cluster ion beam technique is a versatile tool which can be used for controllable formation of nanosize objects as well as modification and processing of surfaces and shallow layers on an atomic scale. The current paper present an overview and analysis of data obtained on a few sets of graphite...... and diamond samples implanted by keV-energy size-selected cobalt and argon clusters. One of the emphases is put on pinning of metal clusters on graphite with a possibility of following selective etching of graphene layers. The other topic of concern is related to the development of scaling law for cluster...

  3. Design of the Faraday Cups in Diamond

    CERN Document Server

    Morgan, A F D

    2005-01-01

    This paper details the work done on the design of the Faraday cups for the Diamond injector. Faraday cups are a basic charge capture device which can be used as reference points for current measurement calibration. Diamond has Faraday cups in positions covering the complete energy range of the injector from the electron gun to the booster synchrotron extraction. Specifically there are cups at 90 keV, 4 MeV, 100 MeV and 3 GeV. An initial design decision was made to make the designs passive to increase reliability and reduce complexity. The 90 keV and 4 MeV cups were modified from an existing design using analytical formulae and MathCAD, while the high energy 100 MeV and 3 GeV designs were done using the EGSnrc Monte Carlo code and MatLAB. The EGSnrc led designs achieved a theoretical electron capture of around 99%, allowing them to be used with reasonable certainty as calibration references. Due to the modest 5Hz repetition rate, power loading of the structures is minimal and active cooling is not required for...

  4. Advanced laser diagnostics for diamond deposition research

    Energy Technology Data Exchange (ETDEWEB)

    Kruger, C.H.; Owano, T.G.; Wahl, E.H. [Stanford Univ., CA (United States)

    1995-12-31

    Chemical Vapor Deposition (CVD) using thermal plasmas is attractive for diamond synthesis applications due to the inherently high reactant densities and throughput, but the associated high gas-phase collision rates in the boundary layer above the substrate produce steep thermal and species gradients which can drive the complex plasma chemistry away from optimal conditions. To understand and control these environments, accurate measurements of temperature and species concentrations within the reacting boundary layer are needed. This is challenging in atmospheric pressure reactors due to the highly luminous environment, steep thermal and species gradients, and small spatial scales. The applicability of degenerate four-wave mixing (DFWM) as a spectroscopic probe of atmospheric pressure reacting plasmas has been investigated. This powerful, nonlinear technique has been applied to the measurement of temperature and radical species concentrations in the boundary layer of a diamond growth substrate immersed in a flowing atmospheric pressure plasma. In-situ measurements of CH and C{sub 2} radicals have been performed to determine spatially resolved profiles of vibrational temperature, rotational temperature, and species concentration. Results of these measurements are compared with the predictions of a detailed numerical simulation.

  5. Diamond - Application to piezoelectric bimorph cantilever sensors

    Science.gov (United States)

    Mortet, V.; Haenen, K.; Potmesil, J.; Vanecek, M.; D'Olieslaeger, M.

    2006-09-01

    Micro-cantilevers are excellent tools to measure tiny forces (from 1 nN up to 10 N) as shown by the development of atomic force microscopy (AFM) techniques. That is the reason why micro-cantilevers are also the most sensitive acoustic sensors. For instance, one can use the variation of the cantilever's resonant frequency to measure mass loading. In this work, we will show first why diamond is the most suitable material for a special type of cantilever sensors: piezoelectric bimorph cantilever sensors. In contrast to other cantilevers, it is possible to actuate piezoelectric bimorph cantilevers and to detect their resonance frequencies simultaneously. Then, we present one application of this type of cantilever: a diamond/AlN cantilever used as a high pressure sensor (up to 7 ar). The sensor operates by monitoring the frequency shift of the first resonant mode (f 1 36.5 kHz). We have measured a sensitivity of 0.155 Hz/mbar in pure nitrogen.

  6. Studies of defects on ion irradiated diamond

    Energy Technology Data Exchange (ETDEWEB)

    Lai, P.F.; Prawer, S.; Spargo, A.E.C.; Bursill, L.A. [Melbourne Univ., Parkville, VIC (Australia). School of Physics

    1996-12-31

    It is known that diamond is amorphized or graphitized when irradiated above a critical dose. Above this critical dose, D{sub c}, the resistance R is found to drop very rapidly due to the formation of graphite regions which overlap at D{sub c} to form a semi-continuous electrically conducting pathway through the sample. One particularly interesting method of studying this transformation is electron energy-loss spectroscopy (EELS). Using EELS, the different phases of carbon can be identified and distinguished from each other using the extended energy-loss fine structure (EXELFS) of the core-loss part of the spectrum. EELS is a sensitive method for determining the electronic structure of small areas of a sample. In this paper, transmission electron microscopy (TEM) and EELS measurements of the ion irradiated diamond were combined in an attempt to correlate the microstructural nature of the ion-beam induced damage to the changes in the electrical and other properties. 7 refs., 1 tab., 2 figs.

  7. Polishing of dental porcelain by polycrystalline diamond.

    Science.gov (United States)

    Nakamura, Yoshiharu; Sato, Hideaki; Ohtsuka, Masaki; Hojo, Satoru

    2010-01-01

    Polycrystalline diamond (PCD) exhibits excellent abrasive characteristics and is commonly used as loose grains for precision machining of hard ceramics and other materials that are difficult to grind and polish. In the present study, we investigated using bonded PCD for polishing dental porcelain, for which a lustrous surface is difficult to obtain by polishing. We compared the surface texture and characteristics of dental porcelain after polishing with bonded PCD with that obtained using bonded monocrystalline diamond (MCD), which is commonly used for this purpose. Polishing was performed at various pressures and rotational speeds on a custom-built polishing apparatus using bonded PCD or MCD with grain sizes of 3.92 μm on specimens consisting of VITA Omega 900 dentin porcelain after firing and then glazing to a specified surface roughness. The surface roughness of the polished porcelain and the abrasion quantity in terms of its polishing depth were measured, and its surface texture and characteristics were investigated. At low polishing pressures, PCD yielded a finer polished surface than MCD. The polishing depth after polishing for 20-30 min was approximately 2-3 μm with PCD and 1-2 μm with MCD. The polished surface was more uniform and smooth with PCD than with MCD.

  8. Diamond photonics for distributed quantum networks

    Science.gov (United States)

    Johnson, Sam; Dolan, Philip R.; Smith, Jason M.

    2017-09-01

    The distributed quantum network, in which nodes comprising small but well-controlled quantum states are entangled via photonic channels, has in recent years emerged as a strategy for delivering a range of quantum technologies including secure communications, enhanced sensing and scalable quantum computing. Colour centres in diamond are amongst the most promising candidates for nodes fabricated in the solid-state, offering potential for large scale production and for chip-scale integrated devices. In this review we consider the progress made and the remaining challenges in developing diamond-based nodes for quantum networks. We focus on the nitrogen-vacancy and silicon-vacancy colour centres, which have demonstrated many of the necessary attributes for these applications. We focus in particular on the use of waveguides and other photonic microstructures for increasing the efficiency with which photons emitted from these colour centres can be coupled into a network, and the use of microcavities for increasing the fraction of photons emitted that are suitable for generating entanglement between nodes.

  9. DIAMONDS: a new Bayesian nested sampling tool*

    Directory of Open Access Journals (Sweden)

    Corsaro Enrico

    2015-01-01

    Full Text Available In the context of high-quality asteroseismic data provided by the NASA Kepler Mission, we developed a new code, termed DIAMONDS (high-DImensional And multi-MOdal NesteD Sampling, for fast Bayesian parameter estimation and model comparison by means of the Nested Sampling Monte Carlo (NSMC algorithm, an efficient and powerful method very suitable for high-dimensional problems (like the peak bagging analysis of solar-like oscillations and multi-modal problems (i.e. problems that show multiple solutions. We applied the code to the peak bagging analysis of solar-like oscillations observed in a challenging F-type star. By means of DIAMONDS one is able to detect the different backgrounds in the power spectrum of the star (e.g. stellar granulation and faculae activity and to understand whether one or two oscillation peaks can be identified or not. In addition, we demonstrate a novel approach to peak bagging based on multi-modality, which is able to reduce significantly the number of free parameters involved in the peak bagging model. This novel approach is therefore of great interest for possible future automatization of the entire analysis technique.

  10. Oncorhynchus nerka population monitoring in the Sawtooth Valley Lakes

    Energy Technology Data Exchange (ETDEWEB)

    Teuscher, D.M.; Taki, D.; Ariwite, K.

    1996-05-01

    Critical habitat for endangered Snake River sockeye salmon includes five rearing lakes located in the Sawtooth Valley of central Idaho. Most of the lakes contain either introduced or endemic kokanee populations. Snake River sockeye occur naturally in Redfish Lake, and are being stocked in Redfish and Pettit Lakes. Because kokanee compete with sockeye for limited food resources, understanding population characteristics of both species such as spawn timing, egg-to-fry survival, distribution and abundance are important components of sockeye recovery. This chapter describes some of those characteristics. In 1995, hydroacoustic estimates of O. nerka densities in the Sawtooth Valley Lakes ranged from 57 to 465 fish/ha. Densities were greatest in Pettit followed by Redfish (167), Alturas (95), and Stanley Lakes. O. nerka numbers increased from 1994 values in Pettit and Alturas Lakes, but declined in Redfish and Stanley. Despite a decline in total lake abundance, O. nerka biomass estimates in Redfish Lake increased. Approximately 144,000 kokanee fry recruited to Redfish Lake from Fishhook Creek. O. nerka fry recruitment to Stanley and Alturas lake was 5,000 and 30,000 fry, respectively. Egg-to-fry survival was 14% in Fishhook and 7% in Stanley Lake Creek. In Fishhook Creek, kokanee spawning escapement was estimated using stream surveys and a weir. Escapement estimates were 4,860 from weir counts, and 7,000 from stream surveys. As part of the kokanee reduction program, 385 of the spawning female kokanee were culled. Escapement for Stanley Lake Creek was only 60 fish, a ten fold decrease from 1994. In Alturas Lake, kokanee spawners dropped by 50% to 1,600.

  11. Draft Supplement to the Environmental Statement Fiscal Year 1976 Proposed Program : Facility Location Evaluation for Cheney-Four Lakes Area Service Study Area 76-7.

    Energy Technology Data Exchange (ETDEWEB)

    United States. Bonneville Power Administration.

    1975-04-15

    Proposed is construction of approximately 26 miles of 230-kV transmission line from the Four Mounds Area west of Spokane to either Cheney or Four Lakes Substation. Proposed also is construction of a new substation in the Four Mounds area. Depending upon final route location chosen, between 20 and 27 miles of new right-of-way would be required between the proposed Greenwood Substation and either Cheney or Four Lakes Substation. Between 25 and 41 miles of access road would also be required. Depending upon the final route selected, the amount of impact upon forest land would range from zero to 97 acres permanently removed. The amount of land temporarily disrupted for rangeland and cropland would be 8 to 13 acres and 30 to 40 acres, respectively. In addition, between approximately 4 and 8 acres of rangeland would be removed due to construction of the proposed new substation. Other impacts would include the removal of wildlife habitat associated with the above mentioned right-of-way requirements. Disturbance to wildlife during construction would occur. Some erosion and sedimentation would occur. Visual impacts would result from clearing rights-of-way through heavily forested areas. Noise and other disturbances to residents will occur, primarily during construction.

  12. 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.

  13. 77 FR 47582 - Great Lakes Pilotage Rates-2013 Annual Review and Adjust; Correction

    Science.gov (United States)

    2012-08-09

    ... SECURITY Coast Guard 46 CFR Part 401 RIN 1625-AB89 Great Lakes Pilotage Rates--2013 Annual Review and..., 2012 (77 FR 45539) proposing rate adjustments for pilotage services on the Great Lakes. The charge rate... email Mr. Todd Haviland, Management & Program Analyst, Office of Great Lakes Pilotage, Commandant (CG...

  14. 77 FR 11752 - 2012 Rates for Pilotage on the Great Lakes

    Science.gov (United States)

    2012-02-28

    ... SECURITY Coast Guard 46 CFR Part 401 RIN 1625-AB70 2012 Rates for Pilotage on the Great Lakes AGENCY: Coast... the Great Lakes, which were last amended in February 2011. The adjustments establish new base rates.... Todd Haviland, Management & Program Analyst, Office of Great Lakes Pilotage, Commandant (CG-5522...

  15. 76 FR 47095 - 2012 Rates for Pilotage on the Great Lakes

    Science.gov (United States)

    2011-08-04

    ... SECURITY Coast Guard 46 CFR Part 401 RIN 1625-AB70 2012 Rates for Pilotage on the Great Lakes AGENCY: Coast... rates for pilotage services on the Great Lakes, which were last amended in February 2011. The proposed.... Todd Haviland, Management & Program Analyst, Office of Great Lakes Pilotage, Commandant (CG-5522...

  16. 77 FR 45539 - Great Lakes Pilotage Rates-2013 Annual Review and Adjustment

    Science.gov (United States)

    2012-08-01

    ...-0409] RIN 1625-AB89 Great Lakes Pilotage Rates--2013 Annual Review and Adjustment AGENCY: Coast Guard... pilotage services on the Great Lakes, which were last amended in February 2012. The proposed adjustments... Haviland, Management & Program Analyst, Office of Great Lakes Pilotage, Commandant (CG-WWM-2), Coast Guard...

  17. Factors controlling hydrochemical and trophic state variables in 86 shallow lakes in Europe

    NARCIS (Netherlands)

    Nõges, P.; Nõges, T.; Tuvikene, L.; Smal, H.; Ligeza, S.; Kornijów, R.; Peczula, W.; Bécares, E.; Garcia-Criado, F.; Alvarez-Carrera, C.; Fernandez-Alaez, C.; Ferriol, C.; Miracle, R.M.; Vicente, E.; Romo, S.; Van Donk, E.; Van de Bund, W.J.; Jensen, J.P.; Gross, E.M.; Hansson, L-A.; Gyllström, M.; Nykänen, M.; De Eyto, E.; Irvine, K.; Stephen, D.; Collings, S.E.; Moss, B.

    2003-01-01

    In order to disentangle the causes of variations in water chemistry among European shallow lakes, we performed standardised sampling programs in 86 lakes along a latitudinal gradient from southern Spain to northern Sweden. Lakes with an area of 0.1 to 27 000 ha and mean depth of 0.4–5.6 m located in

  18. Some Lake Level Control Alternatives for the Great Salt Lake

    OpenAIRE

    Allen, Marvin E.; Christensen, Ronald K.; Riley, J. Paul

    1983-01-01

    Fluctuations of the level of the Great Salt Lake cause large changes in both surface area and shoreline. Developments adjacent to the lake have been damaged by both high and low lake levels; and unless measures are implemented to regulate lake level fluctuations or otherwise to protect these developments, damages will continue. Various possible managment alternatives for mitigating potential damages from lake leve...

  19. 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

  20. 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.

  1. 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)

  2. Polycrystalline-Diamond MEMS Biosensors Including Neural Microelectrode-Arrays.

    Science.gov (United States)

    Varney, Michael W; Aslam, Dean M; Janoudi, Abed; Chan, Ho-Yin; Wang, Donna H

    2011-08-15

    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.

  3. 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.

  4. 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.

  5. 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}.

  6. 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.

  7. Spectroscopic constraints on growth of Siberian mixed-habit diamonds

    Science.gov (United States)

    Skuzovatov, Sergei Yu.; Zedgenizov, Dmitry A.; Rakevich, Alexander L.

    2017-06-01

    Notable within-crystal variability of mineralogical and geochemical properties of single natural diamonds are commonly attributed to changing chemistry of parental fluids, sources of carbon and redox conditions of diamond precipitation. A distinct type of compositional heterogeneity (mixed-habit structure) is well-known to occur in diamonds as well as in many other minerals due to purely "structural" reasons that are unequal crystal chemistry of crystallographically different faces and selective absorption and fractionation of impurities between adjacent growth pyramids. Based on the combined cathodoluminescence, Fourier-transformed infrared spectroscopy and photoluminescence spectroscopy, study of nine diamond crystals with different growth histories and external morphology, but all showing mixed-habit patterns at different growth stages, we show that mixed-diamonds may grow in closed system conditions or with a slowly decreasing growth rate from a media with a much lower impurity content than previously thought. Intracrystal nitrogen distribution seems to be a function of growth rate even in the cases of unusual impurity partitioning between growth sectors. Generally poor with IR-active hydrogen at moderate nitrogen aggregation parameters, studied diamonds likely resemble the low hydrogen content from the growth medium that, for cubic diamonds, was typically suggested hydrogen-rich and a crucial factor for growth of cubic and mixed-habit diamonds. We also show that mixed-habit diamond growth may occur not only in peridotitic suite but also in an extended field of geochemical affinities from high-Ni to low-Ni or maybe even Ni-free environments, such as pyroxenitic or eclogitic.

  8. Enhancement of structure images of interstellar diamond microcrystals by image processing

    Science.gov (United States)

    O'Keefe, Michael A.; Hetherington, Crispin; Turner, John; Blake, David; Freund, Friedemann

    1988-01-01

    Image processed high resolution TEM images of diamond crystals found in oxidized acid residues of carbonaceous chondrites are presented. Two models of the origin of the diamonds are discussed. The model proposed by Lewis et al. (1987) supposes that the diamonds formed under low pressure conditions, whereas that of Blake et al (1988) suggests that the diamonds formed due to particle-particle collisions behind supernova shock waves. The TEM images of the diamond presented support the high pressure model.

  9. Investigation of surface properties of boron doped diamond for developing neuron -machine interface

    OpenAIRE

    Vahidpour, Farnoosh

    2016-01-01

    Summary The main goal of this thesis is to study how diamond films advance the construction of the hybrid biological-solid state interfaces and to construct Micro-Electrode Arrays (MEAs) for neural recordings. First, a literature study was carried out to review diamond applications in biology for in vitro and in vivo and for Microelectrode arrays (MEAs). In order to develop diamond MEAs, nano crystalline diamond (NCD) and boron-doped nano crystalline diamond (BNCD) were synthetized on fuse...

  10. Integrating Climate Change into Great Lakes Protection

    Science.gov (United States)

    Hedman, S.

    2012-12-01

    Climate change is now recognized as one of the greatest threats to the Great Lakes. Projected climate change impacts to the Great Lakes include increases in surface water and air temperature; decreases in ice cover; shorter winters, early spring, and longer summers; increased frequency of intense storms; more precipitation falling as rain in the winter; less snowfall; and variations in water levels, among other effects. Changing climate conditions may compromise efforts to protect and restore the Great Lakes ecosystem and may lead to irrevocable impacts on the physical, chemical, and biological integrity of the Great Lakes. Examples of such potential impacts include the transformation of coastal wetlands into terrestrial ecosystems; reduced fisheries; increased beach erosion; change in forest species composition as species migrate northward; potential increase in toxic substance concentrations; potential increases in the frequency and extent of algal blooms; degraded water quality; and a potential increase in invasive species. The Great Lakes Restoration Initiative, signed into law by President Obama in 2010, represents the commitment of the federal government to protect, restore, and maintain the Great Lakes ecosystem. The GLRI Action Plan, issued in February 2010, identifies five focus areas: - Toxic Substances and Areas of Concern - Invasive Species - Nearshore Health and Nonpoint Source Pollution - Habitat and Wildlife Protection and Restoration - Accountability, Education, Monitoring, Evaluation, Communication, and Partnerships The Action Plan recognizes that the projected impacts of climate change on the Great Lakes have implications across all focus areas and encourages incorporation of climate change considerations into GLRI projects and programs as appropriate. Under the GLRI, EPA has funded climate change-related work by states, tribes, federal agencies, academics and NGOs through competitive grants, state and tribal capacity grants, and Interagency

  11. LAKE-0: a model for the simulation of nuclides transfer in lake scenarios

    Energy Technology Data Exchange (ETDEWEB)

    Garcia-Olivares, A.; Aguero, A.; Pinedo, P.

    1994-07-01

    This report presents documentation and a user's manual for the program LAKE-0, a mathematical model of nuclides transfer in lake scenarios. Mathematical equations and physical principles used to develop the code are presented in section 2. The program use is presented in section 3 including input data sets and output data. Section 4 presents two example problems, and some results. The complete program listing including comments is presented in Appendix A. Nuclides are assumed to center the lake via atmospheric deposition and carried by the water runoff and the dragged sediments from the adjacent catchment. The dynamics of the nuclides inside the lake is based in the model proposed by Codell (11) as modified in (5). The removal of concentration from the lake water is due to out flow from the lake and to the transfer of activity to the button sediments. The model has been applied to the Esthwaite Water (54 degree celsius 2 l'N, 03 degree celsius 00'W at 65 m. asi.) in the frame of the VAMP Aquatic Working Group (8) and to Devoke Water (5 21.5'N, 03H8'W at 230 m. asi.). (Author). 13 refs.

  12. Instrumentation development for electrical conductivity imaging in polycrystalline diamond cutters

    Science.gov (United States)

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

    2013-01-01

    We previously reported on an electrical conductivity non-destructive inspection methodology for polycrystalline diamond cutters. These cylindrical cutters for oil and gas drilling feature a thick polycrystalline diamond layer on a tungsten carbide substrate. We use electrical impedance tomography to image the conductivity in the diamond table. In this paper we report on progress in preparing this instrument for factory deployment. Instrument enhancements include an adjustable part holder, a field-swappable sensor and GPU-enabled software capable of rapidly acquiring images.

  13. Observation of diamond turned OFHC copper using Scanning Tunneling Microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Grigg, D.A.; Russell, P.E.; Dow, T.A.

    1988-12-01

    Diamond turned OFHC copper samples have been observed within the past few months using the Scanning Tunneling Microscope. Initial results have shown evidence of artifacts which may be used to better understand the diamond turning process. The STM`s high resolution capability and three dimensional data representation allows observation and study of surface features unobtainable with conventional profilometry systems. Also, the STM offers a better quantitative means by which to analyze surface structures than the SEM. This paper discusses findings on several diamond turned OFHC copper samples having different cutting conditions. Each sample has been cross referenced using STM and SEM.

  14. Laser processing of diamond-like carbon metal composites

    Science.gov (United States)

    Narayan, Roger Jagdish

    2005-05-01

    Diamond-like carbon (DLC) is a hydrogen-free amorphous material that contains a large fraction of sp 3-hybridized carbon atoms. DLC exhibits hardness, corrosion resistance, and wear resistance properties close to those of diamond. Unfortunately, DLC films contain a large amount of compressive stresses and exhibit poor adhesion to many metal substrates. We have adopted a novel pulsed laser deposition process to incorporate metal atoms into diamond-like carbon films. Visible Raman spectroscopy data suggest that DLC-metal composite films possess less internal compressive stress than as-prepared DLC films. DLC-metal composite films have several potential applications, including use in machine tools and medical prostheses.

  15. Alpha particle response study of polycrstalline diamond radiation detector

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, Amit; Topkar, Anita [Electronics Division, Bhabha Atomic Research Centre, Trombay, Mumbai-400085 (India)

    2016-05-23

    Chemical vapor deposition has opened the possibility to grow high purity synthetic diamond at relatively low cost. This has opened up uses of diamond based detectors for wide range of applications. These detectors are most suitable for harsh environments where standard semiconductor detectors cannot work. In this paper, we present the fabrication details and performance study of polycrystalline diamond based radiation detector. Effect of different operating parameters such as bias voltage and shaping time for charge collection on the performance of detector has been studied.

  16. Results on diamond timing detector for the TOTEM experiment

    Energy Technology Data Exchange (ETDEWEB)

    Bossini, E., E-mail: edoardo.bossini@pi.infn.it [Museo Storico della Fisica e Centro Studi e Ricerche E. Fermi, Rome (Italy); Istituto Nazionale di Fisica Nucleare, Sezione di Pisa (Italy)

    2016-07-11

    We describe the results and status of our R&D on diamond timing detectors for the TOTEM experiment at CERN. Tests with commercial devices have been done and here reported; the unsatisfactory results push us to design a new detector. We present test beams results and the front-end electronics, critical point of the design. Efficiency studies and timing performance dependence from detector capacitance will be also reported. - Highlights: • Diamond particles detector for precise Time Of Flight measurements. • Integrated very low-noise electronics. • Minimum Ionizing Particle detector. • Diamond detector development and characterization.

  17. Technology and equipment for processing diamond materials of modern electronics

    Directory of Open Access Journals (Sweden)

    Mityagin A. Yu.

    2009-02-01

    Full Text Available The methods of selection and sorting of diamonds according to their physical properties by modern physical methods of the analysis are developed, as well as the technologies of precision laser cutting of diamonds, their processing on a basis of thermochemical reactions in gas environment. The experimental installation for polishing and grinding of diamond plates, installation for slicing, installation for plasma-chemical processing are created. The techniques of surface roughness measurement of the processed plates and control of roughness parameters are developed. Some experimental results are given.

  18. Application of Diamond Nanoparticles in Low-Energy Neutron Physics

    Directory of Open Access Journals (Sweden)

    Alexander Strelkov

    2010-03-01

    Full Text Available Diamond, with its exceptionally high optical nuclear potential and low absorption cross-section, is a unique material for a series of applications in VCN (very cold neutron physics and techniques. In particular, powder of diamond nanoparticles provides the best reflector for neutrons in the complete VCN energy range. It allowed also the first observation of quasi-specular reflection of cold neutrons (CN from disordered medium. Effective critical velocity for such a quasi-specular reflection is higher than that for the best super-mirror. Nano-diamonds survive in high radiation fluxes; therefore they could be used, under certain conditions, in the vicinity of intense neutron sources.

  19. Printable, flexible and stretchable diamond for thermal management

    Science.gov (United States)

    Rogers, John A; Kim, Tae Ho; Choi, Won Mook; Kim, Dae Hyeong; Meitl, Matthew; Menard, Etienne; Carlisle, John

    2013-06-25

    Various heat-sinked components and methods of making heat-sinked components are disclosed where diamond in thermal contact with one or more heat-generating components are capable of dissipating heat, thereby providing thermally-regulated components. Thermally conductive diamond is provided in patterns capable of providing efficient and maximum heat transfer away from components that may be susceptible to damage by elevated temperatures. The devices and methods are used to cool flexible electronics, integrated circuits and other complex electronics that tend to generate significant heat. Also provided are methods of making printable diamond patterns that can be used in a range of devices and device components.

  20. CVD diamond coatings on titanium : Characterisation by XRD techniques

    Energy Technology Data Exchange (ETDEWEB)

    Cappuccio, G. [CNR, Frascati, Rome (Italy). Istituto di Strutturistica Chimica]|[INFN-LNF, Frascati, Rome (Italy). Laboratorio Dafne Luce

    1996-09-01

    Here, the authors report an analysis carried out on diamond coatings on titanium substrates to show the potentially of x-ray diffraction techniques in the structural characterisation both of diamond thin films and of the other phases (TiC and TiH{sub 2}) present in the interfacial layer. It should be noted that the composition and microstructure of the interface layers strongly affect the characteristics of the diamond films, particularly adhesion, which is one of the most important elements determining the final quality of the coating.

  1. Diamond-coated ATR prism for infrared absorption spectroscopy of surface-modified diamond nanoparticles

    Czech Academy of Sciences Publication Activity Database

    Remeš, Zdeněk; Kozak, Halyna; Rezek, Bohuslav; Ukraintsev, Egor; Babchenko, Oleg; Kromka, Alexander; Girard, H.A.; Arnault, J.-C.; Bergonzo, P.

    2013-01-01

    Roč. 270, APR (2013), s. 411-417 ISSN 0169-4332 R&D Projects: GA ČR GAP108/12/0910; GA ČR GPP205/12/P331; GA MŠk LH12236; GA MŠk LH12186 Institutional support: RVO:68378271 Keywords : ATR FTIR * CVD * hydrogenation * microwave * nanocrystalline diamond * nanopowder Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 2.538, year: 2013

  2. Salting our freshwater lakes

    Science.gov (United States)

    Bartlett, Sarah L.; Burke, Samantha M.; Doubek, Jonathan P.; Krivak-Tetley, Flora E.; Skaff, Nicholas K.; Summers, Jamie C.; Farrell, Kaitlin J.; McCullough, Ian M.; Morales-Williams, Ana M.; Roberts, Derek C.; Ouyang, Zutao; Scordo, Facundo; Hanson, Paul C.; Weathers, Kathleen C.

    2017-01-01

    The highest densities of lakes on Earth are in north temperate ecosystems, where increasing urbanization and associated chloride runoff can salinize freshwaters and threaten lake water quality and the many ecosystem services lakes provide. However, the extent to which lake salinity may be changing at broad spatial scales remains unknown, leading us to first identify spatial patterns and then investigate the drivers of these patterns. Significant decadal trends in lake salinization were identified using a dataset of long-term chloride concentrations from 371 North American lakes. Landscape and climate metrics calculated for each site demonstrated that impervious land cover was a strong predictor of chloride trends in Northeast and Midwest North American lakes. As little as 1% impervious land cover surrounding a lake increased the likelihood of long-term salinization. Considering that 27% of large lakes in the United States have >1% impervious land cover around their perimeters, the potential for steady and long-term salinization of these aquatic systems is high. This study predicts that many lakes will exceed the aquatic life threshold criterion for chronic chloride exposure (230 mg L−1), stipulated by the US Environmental Protection Agency (EPA), in the next 50 y if current trends continue. PMID:28396392

  3. Genesis of presolar diamonds: Comparative high-resolution transmission electron microscopy study of meteoritic and terrestrial nano-diamonds

    Science.gov (United States)

    Daulton, T. L.; Eisenhour, D. D.; Bernatowicz, T. J.; Lewis, R. S.; Buseck, P. R.

    1996-12-01

    Nano-diamonds isolated from acid dissolution residues of primitive carbonaceous meteorites (Allende and Murchison) were studied using high-resolution transmission electron microscopy. To discriminate among their most likely formation mechanisms, high-pressure shock-induced metamorphism or low-pressure vapor condensation, the microstructures of presolar diamond crystallites were compared to those of (terrestrial) synthesized nano-diamonds. The synthesized diamonds used for comparison in this study were produced by high-pressure shock waves generated in controlled detonations and by direct nucleation and homoepitaxial growth from the vapor phase in low-pressure chemical vapor deposition (CVD)-type processes. Microstructural features were identified that appear unique to shock metamorphism and to nucleation from the vapor phase, respectively. A comparison of these features to the microstructures found in presolar diamonds indicates that the predominant mechanism for presolar diamond formation is a vapor deposition process, suggesting a circumstellar condensation origin. A new presolar grain component has also been identified in the meteoritic residues, the (2H) hexagonal polytype of diamond (lonsdaleite).

  4. Genesis of presolar diamonds: Comparative high-resolution transmission electron microscopy study of meteoritic and terrestrial nano-diamonds

    Energy Technology Data Exchange (ETDEWEB)

    Daulton, T.L. [Washington Univ., St. Louis, MO (United States)]|[Arizona State Univ., Tempe, AZ (United States); Eisenhour, D.D.; Buseck, P.R. [Arizona State Univ., Tempe, AZ (United States)] [and others

    1996-12-01

    Nano-diamonds isolated from acid dissolution residues of primitive carbonaceous meteorites (Allende and Murchison) were studied using high-resolution transmission electron microscopy. To discriminate among their most likely formation mechanisms, high-pressure shock-induced metamorphism or low-pressure vapor condensation. the microstructures of presolar diamond crystallites were compared to those of (terrestrial) synthesized nano-diamonds. The synthesized diamonds used for comparison in this study were produced by high-pressure shock waves generated in controlled detonations and by direct nucleation and homoepitaxial growth from the vapor phase in low-pressure chemical vapor deposition (CVD)-type processes. Microstructural features were identified that appear unique to shock metamorphism and to nucleation from the vapor phase, respectively. A comparison of these features to the microstructures found in presolar diamonds indicates that the predominant mechanism for presolar diamond formation is a vapor deposition process, suggesting a circumstellar condensation origin. A new presolar grain component has also been identified in the meteoritic residues, the (2H) hexagonal polytype of diamond (lonsdaleite). 93 refs., 17 figs., 1 tab.

  5. Bottom-up diamond nanorod growth in HFCVD from nanocrystalline diamond film as a template-free method

    Science.gov (United States)

    Motahari, Hamid; Malekfar, Rasoul

    2017-07-01

    Nanocrystalline diamond (NCD) films are being used in a large number of applications. Also, diamond nanorods (DNRs) exhibit distinctive features that are not present in diamond films, because of the tunable large surface-to-volume ratio and tubular configuration. In this work, we report on the synthesis of DNRs by means of the bottom-up and template-free method from NCD films by the hot filament chemical vapor deposition system. The substrate materials used for diamond deposition were stainless steel (AISI 316) and chromium nitride-coated stainless steel. On both substrates, NCD films and then DNRs have been synthesized. The micro-Raman confirms that the synthesized structure is NCD. In addition, the grazing incident x-ray diffraction pattern confirms the presence of cubic diamond and rhombohedral diamond as a film on the CrN and Cr2N interlayer. Also, the DNRs are encased in an amorphous carbon (a-C) shell. The DNRs are grown on the NCD grains by a bottom-up technology and template-free method. Their orientations are almost random in the diamond thin-film surface. In addition, the density of DNRs on the NCD film for the CrN interlayer is more than for the stainless-steel substrate. The NCD/DNR films are dense, adhesive, continuous, and almost uniform on the CrN-coated stainless-steel substrate.

  6. Epitaxial synthesis of diamond layers on a monocrystalline diamond substrate in a torch microwave plasmatron

    Energy Technology Data Exchange (ETDEWEB)

    Sergeichev, K. F., E-mail: kserg@fpl.gpi.ru; Lukina, N. A. [Prokhorov Institute of General Physics (Russian Federation)

    2011-12-15

    The epitaxial growth of a diamond single-crystal film in a torch microwave discharge excited by a magnetron of a domestic microwave oven with the power of {<=}1 kW in an argon-hydrogen-methane mixture with a high concentration of methane (up to 25% with respect to hydrogen) at atmospheric pressure on a sub-strate of a synthetic diamond single crystal (HPHP) with the orientation (100) and 4 Multiplication-Sign 4 mm in size is obtained. A discharge with the torch diameter of {approx}2 mm and the concentration of the microwave power absorbed in the torch volume of >10{sup 3} W/cm{sup 3} is shown to be effective for epitaxial enlargement of a single crystal of synthetic diamond. The structure of the deposited film with the thickness up to 10 {mu}m with high-quality morphology is investigated with an optical microscope as well as using the methods of the Raman scattering and scanning electron microscopy.

  7. Water-Quality and Lake-Stage Data for Wisconsin Lakes, Water Year 2006

    Science.gov (United States)

    Rose, W.J.; Garn, H.S.; Goddard, G.L.; Marsh, S.B.; Olson, D.L.; Robertson, Dale M.

    2007-01-01

    Wisconsin Water Science Center's Lakes Program is found at http://wi.water.usgs.gov/lake/index.html and http://wi.water.usgs.gov/projects/index.html.

  8. Western Alaska ESI: LAKES (Lake Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains vector polygons representing lakes and land masses used in the creation of the Environmental Sensitivity Index (ESI) for Western Alaska. The...

  9. Application of LANDSAT to the Surveillance of Lake Eutrophication in the Great Lakes Basin. Final Report.

    Science.gov (United States)

    Rogers, Robert H.

    This document reviews the process by which the cost benefits of using LANDSAT on an operational basis in the surveillance of lake eutrophication was established. The program identified the information needs of users conducting on-going water quality programs, transformed these needs into remote sensing requirements, produced LANDSAT maps and data…

  10. Handbook of spectral lines in diamond

    CERN Document Server

    Dischler, Bernhard

    2012-01-01

    This handbook is a breakthrough in the understanding of the large number of spectral lines in diamond. Data on more than 2000 lines and bands are presented in 200 tables, including many unpublished results. With a novel organization scheme, the search for a specific line is greatly simplified as a benefit for researchers and students. In order to meet the interest in the understanding of the spectra, structure assignments for 80 % of the lines are given, of which 15 % only were published before. The majority of the structures for the 300 centers is explained in most cases for the first time. A key instrument in the interpretation is the analysis by donor-acceptor pair transitions. In a special chapter 95 such centers are listed and discussed, of which only two have been published before, the first one by the present author in 1994.

  11. Thermally induced defects in industrial diamond

    CSIR Research Space (South Africa)

    Masina, BN

    2009-03-01

    Full Text Available and qualitative analyses of industrial diamond were performed using a LEO 1525 SEM. The SEM had a high resolution and image quality of 1.5 nm at 20 kV and 3.5 nm at 1 kV for metallic and non metallic materials and also magnification of 20 – 500 000 X... F (a) (b) (c)(a) (b) (c) 110 0 120 0 13 0 0 14 0 0 150 0 16 0 0 17 0 0 0 . 2 0 . 3 0 . 4 0 . 5 0 . 6 0 . 7 0 . 8 0 . 9 1. 0 1. 1 1 3 3 2 cm - 1 1 1 2 0 cm - 1 R aman s h i f t (cm- 1) I n i t i al s amp l e H e at e d w i t h N d : Y...

  12. Diamond photodiodes for x-ray application

    Energy Technology Data Exchange (ETDEWEB)

    Distel, James R [Los Alamos National Laboratory; Smedley, John [BNL; Keister, Jeffrey W [BNL; Muller, Erik [STONY BROOK UNIV.; Jordan - Sweet, Jean [WATSON RESEARCH CENTER; Bohon, Jen [CASE WESTERN RESERVE UNIV.; Dong, Bin [NON LANL

    2009-01-01

    Single crystal high purity CVD diamonds have been metallized and calibrated as photodiodes at the National Synchrotron Light Source (NSLS). Current mode responsivity measurements have been made over a wide range (0.2-28 keV) of photon energies across several beamlines. Linear response has been achieved over ten orders of magnitude of incident flux, along with uniform spatial response. A simple model of responsivity has been used to describe the results, yielding a value of 13.3 {+-} 0.5 eV for the mean pair creation energy. The responsivity vs. photon energy data show a dip for photon energies near the carbon edge (284 eV), indicating incomplete charge collection for carriers created less than one micron from the metallized layer.

  13. 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)

  14. Functionalization of nanocrystalline diamond films with phthalocyanines

    Energy Technology Data Exchange (ETDEWEB)

    Petkov, Christo [Institute of Nanostructure Technologies and Analytics (INA), Center for Interdisciplinary Nanostructure Science and Technology (CINSaT), University of Kassel (Germany); Reintanz, Philipp M. [Institute of Chemistry, Center for Interdisciplinary Nanostructure Science and Technology (CINSaT), University of Kassel (Germany); Kulisch, Wilhelm [Institute of Nanostructure Technologies and Analytics (INA), Center for Interdisciplinary Nanostructure Science and Technology (CINSaT), University of Kassel (Germany); Degenhardt, Anna Katharina [Institute of Chemistry, Center for Interdisciplinary Nanostructure Science and Technology (CINSaT), University of Kassel (Germany); Weidner, Tobias [Max Planck Institute for Polymer Research, Mainz (Germany); Baio, Joe E. [School of Chemical, Biological and Environmental Engineering, Oregon State University, Corvallis, OR (United States); Merz, Rolf; Kopnarski, Michael [Institut für Oberflächen- und Schichtanalytik (IFOS), Kaiserslautern (Germany); Siemeling, Ulrich [Institute of Chemistry, Center for Interdisciplinary Nanostructure Science and Technology (CINSaT), University of Kassel (Germany); Reithmaier, Johann Peter [Institute of Nanostructure Technologies and Analytics (INA), Center for Interdisciplinary Nanostructure Science and Technology (CINSaT), University of Kassel (Germany); Popov, Cyril, E-mail: popov@ina.uni-kassel.de [Institute of Nanostructure Technologies and Analytics (INA), Center for Interdisciplinary Nanostructure Science and Technology (CINSaT), University of Kassel (Germany)

    2016-08-30

    Highlights: • Grafting of phthalocyanines on nanocrystalline diamond films with different terminations. • Pc with different central atoms and side chains synthesized and characterized. • Attachment of Pc on H- and O-terminated NCD studied by XPS and NEXAFS spectroscopy. • Orientation order of phthalocyanine molecules on NCD surface. - Abstract: Phthalocyanine (Pc) derivatives containing different central metal atoms (Mn, Cu, Ti) and different peripheral chains were synthesized and comprehensively characterized. Their interaction with nanocrystalline diamond (NCD) films, as-grown by hot-filament chemical vapor deposition or after their modification with oxygen plasma to exchange the hydrogen termination with oxygen-containing groups, was studied by X-ray photoelectron spectroscopy (XPS) and near-edge X-ray absorption fine structure (NEXAFS) spectroscopy. The elemental composition as determined by XPS showed that the Pc were grafted on both as-grown and O-terminated NCD. Mn, Cu and Ti were detected together with N stemming from the Pc ring and S in case of the Ti-Pc from the peripheral ligands. The results for the elemental surface composition and the detailed study of the N 1s, S 2p and O 1s core spectra revealed that Ti-Pc grafted better on as-grown NCD but Cu-Pc and Mn-Pc on O-terminated films. Samples of Mn-Pc on as-grown and O-terminated NCD were further investigated by NEXAFS spectroscopy. The results showed ordering of the grafted molecules, laying flat on the H-terminated NCD surface while only the macrocycles were oriented parallel to the O-terminated surface with the peripheral chains perpendicular to it.

  15. Tutorial: Asteroseismic Data Analysis with DIAMONDS

    Science.gov (United States)

    Corsaro, Enrico

    Since the advent of the space-based photometric missions such as CoRoT and NASA's Kepler, asteroseismology has acquired a central role in our understanding about stellar physics. The Kepler spacecraft, especially, is still releasing excellent photometric observations that contain a large amount of information not yet investigated. For exploiting the full potential of these data, sophisticated and robust analysis tools are now essential, so that further constraining of stellar structure and evolutionary models can be obtained. In addition, extracting detailed asteroseismic properties for many stars can yield new insights on their correlations to fundamental stellar properties and dynamics. After a brief introduction to the Bayesian notion of probability, I describe the code Diamonds for Bayesian parameter estimation and model comparison by means of the nested sampling Monte Carlo (NSMC) algorithm. NSMC constitutes an efficient and powerful method, in replacement to standard Markov chain Monte Carlo, very suitable for high-dimensional and multimodal problems that are typical of detailed asteroseismic analyses, such as the fitting and mode identification of individual oscillation modes in stars (known as peak-bagging). Diamonds is able to provide robust results for statistical inferences involving tens of individual oscillation modes, while at the same time preserving a considerable computational efficiency for identifying the solution. In the tutorial, I will present the fitting of the stellar background signal and the peak-bagging analysis of the oscillation modes in a red-giant star, providing an example to use Bayesian evidence for assessing the peak significance of the fitted oscillation peaks.

  16. Diamond LED substrate and novel quantum dots.

    Science.gov (United States)

    Sung, James C; Sung, Michael

    2009-02-01

    Nitride LED (e.g., GaN) has become the mainstream of blue light source. The blue light can be converted to white light by exciting a phosphor (e.g., Nichia's YAG or Osram's TAG) with the complementary yellow emission. However, GaN is typically deposited on sapphire (Al2O3) substrates formed by crystal pulling or hexagonal (e.g., 4 H or 6 H) SiC wafers condensed from SiC vapor. In either case, the nitride lattice is ridden (e.g., 10(9)/cm2) with dislocations. The high dislocation density with sapphire is due to the large (>13%) lattice mismatch; and with hexagonal SiC, because of intrinsic defects. Cubic (beta) SiC may be deposited epitaxially using a CVD reactor onto silicon wafer by diffusing the interface and by chemical gradation. A reactive echant (e.g., hydrogen or fluorine) can be introduced periodically to gasify mis-aligned atoms. In this case, large single crystal wafers would be available for the manufacture of high bright LED with superb electro-optical efficiency. The SiC wafer may be coated with diamond film that can eliminate heat in real time. As a result of lower temperature, the nitride LED can be brighter and it will last longer. The blue light of GaN LED formed on SiC on Diamond (SiCON) LED may also be scattered by using novel quantum dots (e.g., 33 atom pairs of CdSe) to form a broad yellow light that blend in with the original blue light to form sunlight-like white light. This would be the ideal source for general illumination (e.g., for indoor) or backlighting (e.g., for LCD).

  17. Homogenisation of sulphide inclusions within diamonds: A new approach to diamond inclusion geochemistry

    Science.gov (United States)

    McDonald, Iain; Hughes, Hannah S. R.; Butler, Ian B.; Harris, Jeffrey W.; Muir, Duncan

    2017-11-01

    Base metal sulphide (BMS) inclusions in diamonds provide a unique insight into the chalcophile and highly siderophile element composition of the mantle. Entombed within their diamond hosts, these provide a more robust (closed system) sample, from which to determine the trace element, Re-Os and S-isotopic compositions of the mantle than mantle xenoliths or orogenic peridotites, as they are shielded from alteration during ascent to the Earth's crust and subsequent surface weathering. However, at temperatures below 1100 °C some BMS inclusions undergo subsolidus re-equilibration from an original monosulphide solid solution (Mss) and this causes fractionation of the major and trace elements within the inclusions. Thus to study the subjects noted above, current techniques require the entire BMS inclusion to be extracted for analyses. Unfortunately, 'flaking' of inclusions during break-out is a frequent occurrence and hence the risk of accidentally under-sampling a portion of the BMS inclusion is inherent in current practices. This loss may have significant implications for Re-Os isotope analyses where incomplete sampling of a Re-rich phase, such as chalcopyrite that typically occurs at the outer margins of BMS inclusions, may induce significant bias in the Re-Os and 187Os/188Os measurements and resulting model and isochron ages. We have developed a method for the homogenisation of BMS inclusions in diamond prior to their break-out from the host stone. Diamonds are heated to 1100 °C and then quenched to chemically homogenise any sulphide inclusions for both major and trace elements. Using X-ray Computed Microtomography (μCT) we determine the shape and spatial setting of multiple inclusions within a host stone and crucially show that the volume of a BMS inclusion is the same both before and after homogenisation. We show that the homogenisation process significantly reduces the inherent variability of in situ analysis when compared with unhomogenised BMS, thereby

  18. Effect of packing density on shock consolidation of diamond powders

    Science.gov (United States)

    Joshi, V. S.; Grebe, H. A.; Thadhani, N. N.; Iqbal, Z.

    1994-07-01

    Diamond powders of different types and particle size distribution were shock consolidated using a plate impact shock recovery system at 1.6 to 2.2 km/s. Single-piece diamond compacts (approximately 12 mm diameter and 2-4 mm thickness) with relative densities in the range of 88-94% of Theoretical Maximum Density (TMD) and less than 5% non-diamond phase, were produced. While the effects of several different variables, e.g., powder pre-treatment, particle size and distribution, and impact conditions, were explored, it was established that the initial green-powder-compact density was the most important variable controlling the densification of diamond powders. In this paper, we will present results of some of the consolidation experiments and the role of initial green density in controlling the final compact density and microstructure.

  19. Texture characteristics of naturally occurring lonsdaleite-containing diamonds

    Science.gov (United States)

    Kharlashina, N. N.; Naletov, A. M.

    1990-08-01

    The crystalline structure of six naturally occurring lonsdaleite-containing diamonds from Iakutia placers was determined using the Borodkina and Spektor (1981) XRD method. The slope angle for recordings of (111) reflections was varied from 0 to 90 deg, while for recording of (110) and (311) reflections, the slope angle was varied from 0 to 70 deg; the results were used to construct polar figures for these plane orientations. The crystalline characteristics observed in the six diamond samples support the hypothesis that the process of lonsdaleite formation in these samples is similar to the synthesis process in synthetic diamonds. The arrangement of the lonsdaleite lattice is constrained by the -110 line oriented direction in the diamond structure.

  20. Nano-Diamonds in Chondritic Interplanetary Dust Particles

    Science.gov (United States)

    Dai, Z. R.; Joswiak, D. J.; Bradley, J. P.; Brownlee, D. E.; Hill, H. G. M.

    2001-01-01

    In-situ acid etching of ultramicrotomed thin sections has lead to the identification of nano-diamonds in interplanetary dust particles. Additional information is contained in the original extended abstract.

  1. Severe wear behaviour of alumina balls sliding against diamond ...

    Indian Academy of Sciences (India)

    Home; Journals; Bulletin of Materials Science; Volume 39; Issue 2. Severe wear behaviour of alumina balls sliding against diamond ceramic coatings. ANURADHA JANA NANDADULAL DANDAPAT MITUN DAS VAMSI KRISHNA BALLA SHIRSHENDU CHAKRABORTY RAJNARAYAN SAHA AWADESH KUMAR MALLIK.

  2. Groundwater discharge area for Diamond Valley, Central Nevada, 1968

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This dataset represents "phreatophyte areas" mapped as part of an analysis of irrigation pumping in Diamond Valley, Nevada published in 1968. The data were digitized...

  3. Hybrid Nanocavity Resonant Enhancement of Color Center Emission in Diamond

    Directory of Open Access Journals (Sweden)

    Paul E. Barclay

    2011-09-01

    Full Text Available Resonantly enhanced emission from the zero-phonon line of a diamond nitrogen-vacancy (NV center in single crystal diamond is demonstrated experimentally using a hybrid whispering gallery mode nanocavity. A 900 nm diameter ring nanocavity formed from gallium phosphide, whose sidewalls extend into a diamond substrate, is tuned onto resonance at a low temperature with the zero-phonon line of a negatively charged NV center implanted near the diamond surface. When the nanocavity is on resonance, the zero-phonon line intensity is enhanced by approximately an order of magnitude, and the spontaneous emission lifetime of the NV is reduced by as much as 18%, corresponding to a 6.3X enhancement of emission in the zero photon line.

  4. Morphological and electrochemical studies of spherical boron doped diamond electrodes

    Energy Technology Data Exchange (ETDEWEB)

    Mendes de Barros, R.C. [IQ/USP, Av. Lineu Prestes, 748, Bloco 2 Superior, Cidade Universitaria, Sao Paulo/SP, 05508-900 (Brazil); Ferreira, N.G. [LAS/INPE, Av. dos Astronautas, 1758, Jardim da Granja, Sao Jose dos Campos/SP, 12245-970 (Brazil); Azevedo, A.F. [LAS/INPE, Av. dos Astronautas, 1758, Jardim da Granja, Sao Jose dos Campos/SP, 12245-970 (Brazil); Corat, E.J. [LAS/INPE, Av. dos Astronautas, 1758, Jardim da Granja, Sao Jose dos Campos/SP, 12245-970 (Brazil); Sumodjo, P.T.A. [IQ/USP, Av. Lineu Prestes, 748, Bloco 2 Superior, Cidade Universitaria, Sao Paulo/SP, 05508-900 (Brazil); Serrano, S.H.P. [IQ/USP, Av. Lineu Prestes, 748, Bloco 2 Superior, Cidade Universitaria, Sao Paulo/SP, 05508-900 (Brazil)]. E-mail: shps@iq.usp.br

    2006-08-14

    Morphological and electrochemical characteristics of boron doped diamond electrode in new geometric shape are presented. The main purpose of this study is a comparison among voltammetric behavior of planar glassy carbon electrode (GCE), planar boron doped diamond electrode (PDDE) and spherical boron doped diamond electrode (SDDE), obtained from similar experimental parameters. SDDE was obtained by the growth of boron doped film on textured molybdenum tip. This electrode does not present microelectrode characteristics. However, its voltammetric peak current, determined at low scan rates, is largest associated to the smallest {delta}E {sub p} values for ferrocyanide system when compared with PDDE or GCE. In addition, the capacitance is about 200 times smaller than that for GCE. These results show that the analytical performance of boron doped diamond electrodes can be implemented just by the change of sensor geometry, from plane to spherical shape.

  5. Selective data analysis for diamond detectors in neutron fields

    Science.gov (United States)

    Weiss, Christina; Frais-Kölbl, Helmut; Griesmayer, Erich; Kavrigin, Pavel

    2017-09-01

    Detectors based on synthetic chemical vapor deposition diamond gain importance in various neutron applications. The superior thermal robustness and the excellent radiation hardness of diamond as well as its excellent electronic properties make this material uniquely suited for rough environments, such as nuclear fission and fusion reactors. The intrinsic electronic properties of single-crystal diamond sensors allow distinguishing various interactions in the detector. This can be used to successfully suppress background of γ-rays and charged particles in different neutron experiments, such as neutron flux measurements in thermal nuclear reactors or cross-section measurements in fast neutron fields. A novel technique of distinguishing background reactions in neutron experiments with diamond detectors will be presented. A proof of principle will be given on the basis of experimental results in thermal and fast neutron fields.

  6. Analysis of Laser-Brazed Diamond Particle Microstructures

    Directory of Open Access Journals (Sweden)

    Zhibo YANG

    2015-11-01

    Full Text Available Brazing diamond particles to a steel substrate using Ni-based filler alloy was carried out via laser in an argon atmosphere. The brazed diamond particles were detected by scanning electron microscope (SEM, X-ray diffraction (XRD, and energy dispersive X-ray spectroscopy (EDS. The formation mechanism of carbide layers was discussed. All the results indicated that a high-strength bond between the diamond particles and the steel substrate was successfully realized. The chromium in the Ni-based alloy segregated preferentially to the surfaces of the diamonds to form a chromium-rich reaction product, and the bond between the alloy and the steel substrate was established through a cross-diffusion of iron and Ni-based alloy.DOI: http://dx.doi.org/10.5755/j01.ms.21.4.9626

  7. Selective data analysis for diamond detectors in neutron fields

    Directory of Open Access Journals (Sweden)

    Weiss Christina

    2017-01-01

    Full Text Available Detectors based on synthetic chemical vapor deposition diamond gain importance in various neutron applications. The superior thermal robustness and the excellent radiation hardness of diamond as well as its excellent electronic properties make this material uniquely suited for rough environments, such as nuclear fission and fusion reactors. The intrinsic electronic properties of single-crystal diamond sensors allow distinguishing various interactions in the detector. This can be used to successfully suppress background of γ-rays and charged particles in different neutron experiments, such as neutron flux measurements in thermal nuclear reactors or cross-section measurements in fast neutron fields. A novel technique of distinguishing background reactions in neutron experiments with diamond detectors will be presented. A proof of principle will be given on the basis of experimental results in thermal and fast neutron fields.

  8. New developments on diamond photodetector for VUV solar observations

    Science.gov (United States)

    Ben Moussa, A.; Soltani, A.; Haenen, K.; Kroth, U.; Mortet, V.; Barkad, H. A.; Bolsee, D.; Hermans, C.; Richter, M.; DeJaeger, J. C.; Hochedez, J. F.

    2008-03-01

    A new large-size metal-semiconductor-metal photoconductor device of 4.6 mm in diameter based on diamond material has been reprocessed and characterized in the vacuum-ultraviolet (VUV) wavelength range. The metal finger contacts have been processed to 2 µm in width with spacing between the contacts of 5 µm for a bias voltage of 5 V. The responsivity, stability, linearity and homogeneity have been tested. Solutions and progresses on diamond processing are identified and are reported. In the VUV wavelength range of interest, the diamond photodetector is sensitive with a maximum response of 48 mA W-1 at 210 nm with a corresponding external quantum efficiency of 42%, homogenous and stable under short irradiation. It indicates a 200-400 nm rejection ratio of more than four orders of magnitude and demonstrates the advantages of diamond-based detectors in terms of high rejection ratio and high output signal for VUV solar observation missions.

  9. Structural evolution during chemical vapor deposition of diamond thin films

    Science.gov (United States)

    Morell, G.; Cancel, L. M.; Figueroa, O. L.; González, J. A.; Weiner, B. R.

    2000-11-01

    In situ phase-modulated ellipsometry was employed to monitor the nucleation and growth processes of diamond thin films fabricated by chemical vapor deposition. The effective extinction coefficient (k) at 1.96 eV was used as a basis for dividing the deposition process into intervals. The film growth was aborted at various k values yielding diamond film samples that represent snapshots of the growth process at different stages. Ex situ characterization of the films was performed using Raman spectroscopy, scanning electron microscopy, and x-ray diffraction. The results indicate that the diamond film deposition process consists of various stages in which the crystalline quality, the net compressive stress, and the relative amount of non-sp3 carbon follow different trends. A correlation between the effective k value measured in situ and the film microstructure characterized ex situ was established which enables the monitoring of the diamond film growth process in real time.

  10. Diverging diamond interchange performance evaluation (I-44 and Route 13)

    Science.gov (United States)

    2011-02-01

    Performance evaluation was conducted on the first diverging diamond interchange (DDI) or double : crossover interchange (DCD) constructed in the United States. This evaluation assessed traffic operations, safety and : public perceptions t...

  11. Bulk diamond optical waveguides fabricated by focused femtosecond laser pulses

    Science.gov (United States)

    Hadden, J. P.; Sotillo, Belén.; Bharadwaj, Vibhav; Rampini, Stefano; Bosia, Federico; Picollo, Federico; Sakakura, Masaaki; Chiappini, Andrea; Fernandez, Toney T.; Osellame, Roberto; Miura, Kiyotaka; Ferrari, Maurizio; Ramponi, Roberta; Olivero, Paolo; Barclay, Paul E.; Eaton, Shane M.

    2017-02-01

    Diamond's nitrogen-vacancy (NV) centers show great promise in sensing applications and quantum computing due to their long electron spin coherence time and their ability to be located, manipulated and read out using light. The electrons of the NV center, largely localized at the vacancy site, combine to form a spin triplet, which can be polarized with 532- nm laser light, even at room temperature. The NV's states are isolated from environmental perturbations making their spin coherence comparable to trapped ions. An important breakthrough would be in connecting, using waveguides, multiple diamond NVs together optically. However, the inertness of diamond is a significant hurdle for the fabrication of integrated optics similar to those that revolutionized silicon photonics. In this work we show the possibility of buried waveguide fabrication in diamond, enabled by focused femtosecond high repetition rate laser pulses. We use μRaman spectroscopy to gain better insight into the structure and refractive index profile of the optical waveguides.

  12. 11B nuclear magnetic resonance in boron-doped diamond

    Directory of Open Access Journals (Sweden)

    Miwa Murakami, Tadashi Shimizu, Masataka Tansho and Yoshihiko Takano

    2008-01-01

    Full Text Available This review summarizes recent results obtained by 11B solid-state nuclear magnetic resonance (NMR on boron-doped diamond, grown by the high-pressure high-temperature (HPHT or chemical vapor deposition techniques. Simple single-pulse experiments as well as advanced two-dimensional NMR experiments were applied to the boron sites in diamond. It is shown that magic-angle spinning at magnetic fields above 10 T is suitable for observation of high-resolution 11B spectra of boron-doped diamond. For boron-doped HPHT diamonds, the existence of the excess boron that does not contribute to electrical conductivity was confirmed and its 11B NMR signal was characterized. The point-defect structures (B+H complexes and -B-B-/-B-C-B- clusters, postulated previously for the excess boron, were discarded and graphite-like structures were assigned instead.

  13. Mechanical stresses and amorphization of ion-implanted diamond

    Science.gov (United States)

    Khmelnitsky, R. A.; Dravin, V. A.; Tal, A. A.; Latushko, M. I.; Khomich, A. A.; Khomich, A. V.; Trushin, A. S.; Alekseev, A. A.; Terentiev, S. A.

    2013-06-01

    Scanning white light interferometry and Raman spectroscopy were used to investigate the mechanical stresses and structural changes in ion-implanted natural diamonds with different impurity content. The uniform distribution of radiation defects in implanted area was obtained by the regime of multiple-energy implantation of keV He+ ions. A modification of Bosia's et al. (Nucl. Instrum. Meth. B 268 (2010) 2991) method for determining the internal stresses and the density variation in an ion-implanted diamond layer was proposed that suggests measuring, in addition to the surface swelling of a diamond plate, the radius of curvature of the plate. It is shown that, under multiple-energy implantation of He+, mechanical stresses in the implanted layer may be as high as 12 GPa. It is shown that radiation damage reaches saturation for the implantation fluence characteristic of amorphization of diamond but is appreciably lower than the graphitization threshold.

  14. The first bump-bonded pixel detectors on CVD diamond

    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; Fried, 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; Krammer, Manfred; Lo Giudice, A; Lü, R; Manfredi, P F; Manfredotti, C; Marshall, R D; Meier, D; Mishina, M; Oh, A; Palmieri, V G; Pan, L S; Peitz, A; Pernicka, Manfred; Pirollo, S; Polesello, P; Pretzl, Klaus P; Re, V; Riester, J L; Roe, S; Roff, D G; Rudge, A; Schnetzer, S R; Sciortino, S; Speziali, V; Stelzer, H; Steuerer, J; Stone, R; Tapper, R J; Tesarek, R J; Trawick, M L; Trischuk, W; Turchetta, R; Vittone, E; Wagner, A; Walsh, A M; Wedenig, R; Weilhammer, Peter; Zeuner, W; Ziock, H J; Zöller, M; Charles, E; Ciocio, A; Dao, K; Einsweiler, Kevin F; Fasching, D; Gilchriese, M G D; Joshi, A; Kleinfelder, S A; Milgrome, O; Palaio, N; Richardson, J; Sinervo, P K; Zizka, G

    1999-01-01

    Diamond is a nearly ideal material for detecting ionising radiation. Its outstanding radiation hardness, fast charge collection and low leakage current allow it to be used in high radiation environments. These characteristics make diamond sensors particularly appealing for use in the next generation of pixel detectors. Over the last year, the RD42 collaboration has worked with several groups that have developed pixel readout electronics in order to optimise diamond sensors for bump-bonding. This effort resulted in an operational diamond pixel sensor that was tested in a pion beam. We demonstrate that greater than 98565544f the channels were successfully bump-bonded and functioning. The device shows good overall hit efficiency as well as clear spatial hit correlation to tracks measured in a silicon reference telescope. A position resolution of 14.8 mu m was observed, consistent with expectations given the detector pitch. (13 refs).

  15. Microscopic properties of MPCVD diamond coatings studied by ...

    Indian Academy of Sciences (India)

    photoluminescence (PL) spectroscopy techniques. In this paper we report a comparison of the overall quality of MPCVD polycrystalline diamond coatings grown under different processing conditions in terms of stress distribution, thickness uniformity ...

  16. Microscopic properties of MPCVD diamond coatings studied by ...

    Indian Academy of Sciences (India)

    photoluminescence (PL) spectroscopy techniques. In this paper we report a comparison of the overall quality of MPCVD polycrystalline diamond coatings grown under different processing conditions in terms of stress distribution, thickness uniformity and ...

  17. Lake Mead, NV

    Science.gov (United States)

    1982-01-01

    Lake Mead, Nevada, (36.0N, 114.5E) where the water from the Colorado River empties after it's 273 mile journey through the Grand Canyon of Arizona is the subject of this photo. Other features of interest are Hoover Dam on the south shore of Lake Mead where cheap hydroelectric power is secondary to the water resources made available in this northern desert region and the resort city of Las Vegas, just to the west of Lake Mead.

  18. Extreme drought causes distinct water acidification and eutrophication in the Lower Lakes (Lakes Alexandrina and Albert), Australia

    Science.gov (United States)

    Li, Siyue; Bush, Richard T.; Mao, Rong; Xiong, Lihua; Ye, Chen

    2017-01-01

    Droughts are set to increase in frequency and magnitude with climate change and water extraction, and understanding their influence on ecosystems is urgent in the Holocene. Low rainfall across the Murray-Darling Basin (MDB) of Australia resulted in an unprecedented water level decline in the Lower Lakes (Lakes Alexandrina and Albert) at the downstream end of the river system. A comprehensive data covering pre-drought (2004-2006), drought (2007-2010) and post-drought (2010-2013) was firstly used to unravel drought effects on water quality in the contrasting main parts and margins of the two Lakes, particularly following water acidification resulting from acid sulfate soil oxidation. Salinity, nutrients and Chl-a significantly increased during the drought in the Lake main waterbody, while pH remained stable or showed minor shifts. In contrast to the Lake Alexandrina, total dissolved solid (TDS) and electrical conductivity (EC) during the post-drought more than doubled the pre-drought period in the Lake Albert as being a terminal lake system with narrow and shallow entrance. Rewetting of the exposed pyrite-containing sediment resulted in very low pH (below 3) in Lake margins, which positively contributed to salinity increases via SO42- release and limestone dissolution. Very acidic water (pH 2-3) was neutralised naturally by lake refill, but aerial limestone dosing was required for neutralisation of water acidity during the drought period. The Lower Lakes are characterized as hypereutrophic with much higher salinity, nutrient and algae concentrations than guideline levels for aquatic ecosystem. These results suggest that, in the Lower Lakes, drought could cause water quality deterioration through water acidification and increased nutrient and Chl-a concentrations, more effective water management in the lake catchment is thus crucial to prevent the similar water quality deterioration since the projected intensification of droughts. A comparative assessment on lake

  19. [Ecosystem services valuation of Qinghai Lake].

    Science.gov (United States)

    Jiang, Bo; Zhang, Lu; Ouyang, Zhi-yun

    2015-10-01

    Qinghai Lake is the largest inland and salt water lake in China, and provides important ecosystem services to beneficiaries. Economic valuation of wetland ecosystem services from Qinghai Lake can reveal the direct contribution of lake ecosystems to beneficiaries using economic data, which can advance the incorporation of wetland protection of Qinghai Lake into economic tradeoffs and decision analyses. In this paper, we established a final ecosystem services valuation system based on the underlying ecological mechanisms and regional socio-economic conditions. We then evaluated the eco-economic value provided by the wetlands at Qinghai Lake to beneficiaries in 2012 using the market value method, replacement cost method, zonal travel cost method, and contingent valuation method. According to the valuation result, the total economic values of the final ecosystem services provided by the wetlands at Qinghai Lake were estimated to be 6749.08 x 10(8) yuan RMB in 2012, among which the value of water storage service and climate regulation service were 4797.57 x 10(8) and 1929.34 x 10(8) yuan RMB, accounting for 71.1% and 28.6% of the total value, respectively. The economic value of the 8 final ecosystem services was ranked from greatest to lowest as: water storage service > climate regulation service > recreation and tourism service > non-use value > oxygen release service > raw material production service > carbon sequestration service > food production service. The evaluation result of this paper reflects the substantial value that the wetlands of Qinghai Lake provide to beneficiaries using monetary values, which has the potential to help increase wetland protection awareness among the public and decision-makers, and inform managers about ways to create ecological compensation incentives. The final ecosystem service evaluation system presented in this paper will offer guidance on separating intermediate services and final services, and establishing monitoring programs for

  20. Furbearer Management Plan : Rice Lake National Wildlife Refuge [draft

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The Rice Lake NWR Furbearer Management Plan directs the management and regulation of trapping. The furbearer management program directly supports the environmental...

  1. Benton Lake National Wildlife Refuge : Fur Management Plan

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The Benton Lake NWR Fur Management Plan directs the management and regulation of trapping. The furbearer management program directly supports the environmental...

  2. Great Lakes Literacy Principles

    Science.gov (United States)

    Fortner, Rosanne W.; Manzo, Lyndsey

    2011-03-01

    Lakes Superior, Huron, Michigan, Ontario, and Erie together form North America's Great Lakes, a region that contains 20% of the world's fresh surface water and is home to roughly one quarter of the U.S. population (Figure 1). Supporting a $4 billion sport fishing industry, plus $16 billion annually in boating, 1.5 million U.S. jobs, and $62 billion in annual wages directly, the Great Lakes form the backbone of a regional economy that is vital to the United States as a whole (see http://www.miseagrant.umich.edu/downloads/economy/11-708-Great-Lakes-Jobs.pdf). Yet the grandeur and importance of this freshwater resource are little understood, not only by people in the rest of the country but also by many in the region itself. To help address this lack of knowledge, the Centers for Ocean Sciences Education Excellence (COSEE) Great Lakes, supported by the U.S. National Science Foundation and the National Oceanic and Atmospheric Administration, developed literacy principles for the Great Lakes to serve as a guide for education of students and the public. These “Great Lakes Literacy Principles” represent an understanding of the Great Lakes' influences on society and society's influences on the Great Lakes.

  3. Analysis of the influence of tool dynamics in diamond turning

    Energy Technology Data Exchange (ETDEWEB)

    Fawcett, S.C.; Luttrell, D.E.; Keltie, R.F.

    1988-12-01

    This report describes the progress in defining the role of machine and interface dynamics on the surface finish in diamond turning. It contains a review of literature from conventional and diamond machining processes relating tool dynamics, material interactions and tool wear to surface finish. Data from experimental measurements of tool/work piece interface dynamics are presented as well as machine dynamics for the DTM at the Center.

  4. A 3D diamond detector for particle tracking

    Energy Technology Data Exchange (ETDEWEB)

    Artuso, M. [Syracuse University, Syracuse, NY (United States); Bachmair, F.; Bäni, L. [ETH Zürich, Zürich (Switzerland); Bartosik, M. [CERN, Geneva (Switzerland); Beacham, J. [The Ohio State University, Columbus, OH (United States); Bellini, V. [INFN/University of Catania, Catania (Italy); Belyaev, V. [MEPHI Institute, Moscow (Russian Federation); Bentele, B. [University of Colorado, Boulder, CO (United States); Berdermann, E. [GSI, Darmstadt (Germany); Bergonzo, P. [CEA-LIST Technologies Avancees, Saclay (France); Bes, A. [LPSC-Grenoble, Grenoble (France); Brom, J-M. [IPHC, Strasbourg (France); Bruzzi, M. [INFN/University of Florence, Florence (Italy); Cerv, M. [CERN, Geneva (Switzerland); Chau, C. [University of Toronto, Toronto, ON (Canada); Chiodini, G. [INFN-Lecce, Lecce (Italy); Chren, D. [Czech Technical University, Prague (Czech Republic); Cindro, V. [Jožef Stefan Institute, Ljubljana (Slovenia); Claus, G. [IPHC, Strasbourg (France); Collot, J. [LPSC-Grenoble, Grenoble (France); and others

    2016-07-11

    In the present study, results towards the development of a 3D diamond sensor are presented. Conductive channels are produced inside the sensor bulk using a femtosecond laser. This electrode geometry allows full charge collection even for low quality diamond sensors. Results from testbeam show that charge is collected by these electrodes. In order to understand the channel growth parameters, with the goal of producing low resistivity channels, the conductive channels produced with a different laser setup are evaluated by Raman spectroscopy.

  5. Mantle-derived fluids in diamond micro-inclusions

    Science.gov (United States)

    Navon, O.; Hutcheon, I. D.; Rossman, G. R.; Wasserburg, G. J.

    1988-01-01

    Microinclusions in diamonds from Zaire and Botswana differ in composition from the more common large inclusions of the peridotitic or eclogitic assemblages. These sub-micrometer inclusions resemble potassic magmas in their composition, but are enriched in H2O, CO2(3-), and K2O and depleted in MgO. This composition represents a volatile-rich fluid or melt from the upper mantle, which was trapped in the diamonds as they grew.

  6. Polycrystalline CVD diamond device level modeling for particle detection applications

    Science.gov (United States)

    Morozzi, A.; Passeri, D.; Kanxheri, K.; Servoli, L.; Lagomarsino, S.; Sciortino, S.

    2016-12-01

    Diamond is a promising material whose excellent physical properties foster its use for radiation detection applications, in particular in those hostile operating environments where the silicon-based detectors behavior is limited due to the high radiation fluence. Within this framework, the application of Technology Computer Aided Design (TCAD) simulation tools is highly envisaged for the study, the optimization and the predictive analysis of sensing devices. Since the novelty of using diamond in electronics, this material is not included in the library of commercial, state-of-the-art TCAD software tools. In this work, we propose the development, the application and the validation of numerical models to simulate the electrical behavior of polycrystalline (pc)CVD diamond conceived for diamond sensors for particle detection. The model focuses on the characterization of a physically-based pcCVD diamond bandgap taking into account deep-level defects acting as recombination centers and/or trap states. While a definite picture of the polycrystalline diamond band-gap is still debated, the effect of the main parameters (e.g. trap densities, capture cross-sections, etc.) can be deeply investigated thanks to the simulated approach. The charge collection efficiency due to β -particle irradiation of diamond materials provided by different vendors and with different electrode configurations has been selected as figure of merit for the model validation. The good agreement between measurements and simulation findings, keeping the traps density as the only one fitting parameter, assesses the suitability of the TCAD modeling approach as a predictive tool for the design and the optimization of diamond-based radiation detectors.

  7. New results on diamond pixel sensors using ATLAS frontend electronics

    CERN Document Server

    Keil, Markus; Berdermann, E; Bergonzo, P; de Boer, Wim; Bogani, F; Borchi, E; Brambilla, A; Bruzzi, Mara; Colledani, C; Conway, J; D'Angelo, P; Dabrowski, W; Delpierre, P A; Dulinski, W

    2003-01-01

    Diamond is a promising sensor material for future collider experiments due to its radiation hardness. Diamond pixel sensors have been bump bonded to an ATLAS pixel readout chip using PbSn solder bumps. Single chip devices have been characterised by lab measurements and in a high-energy pion beam at CERN. Results on charge collection, spatial resolution, efficiency and the charge carrier lifetime are presented.

  8. Single cell magnetic imaging using a quantum diamond microscope

    Science.gov (United States)

    Park, H.; Weissleder, R.; Yacoby, A.; Lukin, M. D.; Lee, H.; Walsworth, R. L.; Connolly, C. B.

    2015-01-01

    We apply a quantum diamond microscope to detection and imaging of immunomagnetically labeled cells. This instrument uses nitrogen-vacancy (NV) centers in diamond for correlated magnetic and fluorescence imaging. Our device provides single-cell resolution and two orders of magnitude larger field of view (~1 mm2) than previous NV imaging technologies, enabling practical applications. To illustrate, we quantify cancer biomarkers expressed by rare tumor cells in a large population of healthy cells. PMID:26098019

  9. Formation of a silicon terminated (100) diamond surface

    Energy Technology Data Exchange (ETDEWEB)

    Schenk, Alex, E-mail: A.Schenk@latrobe.edu.au; Sear, Michael; Pakes, Chris, E-mail: C.Pakes@latrobe.edu.au [Department of Chemistry and Physics, La Trobe University, Bundoora, Victoria 3086 (Australia); Tadich, Anton [Department of Chemistry and Physics, La Trobe University, Bundoora, Victoria 3086 (Australia); Australian Synchrotron, 800 Blackburn Road, Clayton, Victoria 3168 (Australia); O' Donnell, Kane M. [Department of Physics, Astronomy and Medical Radiation Science, Curtin University, Bentley, Western Australia 6102 (Australia); Ley, Lothar [Department of Chemistry and Physics, La Trobe University, Bundoora, Victoria 3086 (Australia); Institut für Technische Physik, Universität Erlangen, Staudtstrasse 1, Erlangen D-91058 (Germany); Stacey, Alastair [School of Physics, University of Melbourne, Parkville, Victoria 3010 (Australia)

    2015-05-11

    We report the preparation of an ordered silicon terminated diamond (100) surface with a two domain 3 × 1 reconstruction as determined by low energy electron diffraction. Based on the dimensions of the surface unit cell and on chemical information provided by core level photoemission spectra, a model for the structure is proposed. The termination should provide a homogeneous, nuclear, and electron spin-free surface for the development of future near-surface diamond quantum device architectures.

  10. Impurity impact ionization avalanche in p-type diamond

    OpenAIRE

    Mortet, Vincent; Soltani, A.

    2012-01-01

    Electrical conductivity of a highly boron doped chemical vapor deposited diamond thin film has been studied at different temperatures under high electric field conditions. Current-voltage characteristics have been measured using pulsed technique to reduce thermal effects. Experimental results evidence deep impurity impact ionization avalanche in p-type diamond up to room temperature. (C) 2011 American Institute of Physics. Physics; Applied; electrical conduction; low temperatures; germaniu...

  11. Stock Market Reactions to Conflict Diamond Trading Restrictions and Controversies

    OpenAIRE

    William Seitz

    2012-01-01

    In this paper, I explore the reactions of financial market participants to news relating to the Kimberley Process Certification Scheme (KPCS), a body that regulates aspects of global diamond production and trade. I use an event study approach with data on the returns for shares of leading global mining and jewelry retail companies over the period from 1999 to 2011. I show that the most influential dates related to the KPCS for diamond mining companies were associated with regulatory actions i...

  12. Electrochemical characterization on semiconductors p-type CVD diamond electrodes

    OpenAIRE

    Ferreira, N.G.; Silva, L. L. G.; Corat, E. J.; Trava-Airoldi, V. J.; K. Iha

    1999-01-01

    Semiconductor boron-doped CVD diamond films were prepared on Si substrates by the hot filament technique. The surface morphology analysis by SEM presented continuous and well faceted films. The samples were grown with different boron concentrations by controlling the B/C ratio in the feeding gas. Raman results showed a drastic change of diamond films for different doping levels. The characteristic line at 1332 cm-1decreases and shifts to lower energy as a function of the film resistivity. It ...

  13. Study of defects in CVD and ultradisperse diamond

    OpenAIRE

    Iakoubovskii, K; Adriaenssens, G.J.; MEYKENS, Kristien; Nesladek, Milos; Vul, AY; Osipov, VY

    1999-01-01

    Characterization of defects in chemical vapor deposition (CVD) and detonation synthesis ultradisperse diamond (UDD) is reported. Electron Spin Resonance, Raman, and photothermal deflection spectroscopies show that sp(2)-bonded carbon is a dominant defect in UDD diamond. Although UDD was made from trinitrotoluene, no substitutional nitrogen was detected. Photoluminescence (PL) from CVD films showed narrow lines at 1.68, 1.945 and 2.156 eV, in addition to broad red and green bands, while only a...

  14. Fundamental Studies of Diamond Growth and Surface Reactions

    Science.gov (United States)

    1994-07-01

    the material. In the diamond gem industry, mechanical polishing procedures have been developed to obtain an optical quality finish on small-scale...with unpolished samples. The methodology for the technique is described in two journal articlesl6. 17. I 6.0 Characterization of Spectroscopic...sample. Thedegree of improvement in surface roughness in the diamond films can be seen in the Dektak profiles in Fig. 6. The unpolished film had a

  15. Jordan domain and Fatou set concerning diamond-like hierarchical Potts models

    Science.gov (United States)

    Jianyong, Qiao; Junyang, Gao

    2007-01-01

    For the Potts models on the diamond-like hierarchical lattice, the domains of the complex phases are indeed the Fatou components of a family of rational maps. In this paper, we deal with the relationships between this family of Fatou components and the Jordan domains and describe the topological structures of this family of Fatou components completely. The research was supported by the National Natural Science Foundation of China (Grant No 10625107) and the Program for New Century Excellent Talents in University (Grant No 04-0490).

  16. Phonon conduction in GaN-diamond composite substrates

    Science.gov (United States)

    Cho, Jungwan; Francis, Daniel; Altman, David H.; Asheghi, Mehdi; Goodson, Kenneth E.

    2017-02-01

    The integration of strongly contrasting materials can enable performance benefits for semiconductor devices. One example is composite substrates of gallium nitride (GaN) and diamond, which promise dramatically improved conduction cooling of high-power GaN transistors. Here, we examine phonon conduction in GaN-diamond composite substrates fabricated using a GaN epilayer transfer process through transmission electron microscopy, measurements using time-domain thermoreflectance, and semiclassical transport theory for phonons interacting with interfaces and defects. Thermoreflectance amplitude and ratio signals are analyzed at multiple modulation frequencies to simultaneously extract the thermal conductivity of GaN layers and the thermal boundary resistance across GaN-diamond interfaces at room temperature. Uncertainties in the measurement of these two properties are estimated considering those of parameters, including the thickness of a topmost metal transducer layer, given as an input to a multilayer thermal model, as well as those associated with simultaneously fitting the two properties. The volume resistance of an intermediate, disordered SiN layer between the GaN and diamond, as well as a presence of near-interfacial defects in the GaN and diamond, dominates the measured GaN-diamond thermal boundary resistances as low as 17 m2 K GW-1. The GaN thermal conductivity data are consistent with the semiclassical phonon thermal conductivity integral model that accounts for the size effect as well as phonon scattering on point defects at concentrations near 3 × 1018 cm-3.

  17. Surface chemical studies of chemical vapour deposited diamond thin films

    CERN Document Server

    Proffitt, S

    2001-01-01

    could not easily be correlated to the bulk film properties. It is suggested that electron emission arises from the graphite component of graphite- diamond grain boundaries that are present in the nanocrystalline films. species. The adsorbed O and Cl species are more strongly bound to the K layer than they are to the diamond substrate, so thermal desorption of K from the K/CI/diamond or K/O/diamond surface results also in the simultaneous loss ofO and Cl. The phosphorus precursor trisdimethylaminophosphine (TDMAP) has a negligible reactive sticking probability on the clean diamond surface. This can be increased by thermal cracking of the gas phase precursor by a heated filament, resulting in non-activated adsorption to produce an adlayer containing a mixture of surface-bound ligands and phosphorus containing species. The ligands were readily lost upon heating, leaving P, some of which was lost from the surface at higher temperatures. Pre-hydrogenation of the diamond surface inhibited the uptake of cracked TDMA...

  18. Quasiparticle energies and dielectric functions of diamond polytypes

    Science.gov (United States)

    Sakurai, Masahiro; Chelikowsky, James R.; Louie, Steven G.; Saito, Susumu

    2017-10-01

    We perform ab initio many-body Green's function calculations to investigate the quasiparticle energies and optical properties of diamond polytypes that have been predicted to be producible via a pressure-induced structural phase transition from carbon nanotube solids. We find, through quasiparticle band-structure calculations within the G W approximation, that the band gaps of two hexagonal (2 H - and 4 H -type) polytypes of diamond differ significantly from that of cubic diamond as well as from that of the crystalline s p3 carbon phase with a body-centered-tetragonal structure, called bct C4. We also examine the dielectric functions of three polytypes of diamond (cubic, 2 H , and 4 H ) by employing the G W plus Bethe-Salpeter equation approach. The calculated optical absorption spectra are found to be distinct from each other. The lattice mismatches of carbon layers of these diamond polytypes are very small and the total-energy differences are also small. Our work opens up the possibility of fabricating diamond superlattices with various electronic and optoelectronic properties by utilizing and controlling the different stacking sequences of carbon layers.

  19. Diamond dosimetry: Outcomes of the CANDIDO and CONRAD INFN projects

    Energy Technology Data Exchange (ETDEWEB)

    Bucciolini, M. [Dipartimento di Fisiopatologia dell' Universita and INFN, Florence (Italy)]. E-mail: marta@dfc.unifi.it; Borchi, E. [Dipartimento di Energetica dell' Universita and INFN, Florence (Italy); Bruzzi, M. [Dipartimento di Energetica dell' Universita and INFN, Florence (Italy); Casati, M. [Dipartimento di Fisiopatologia dell' Universita and INFN, Florence (Italy); Cirrone, P. [Laboratori Nazionali del SUD, INFN, Catania (Italy); Cuttone, G. [Laboratori Nazionali del SUD, INFN, Catania (Italy); De Angelis, C. [Dipartimento di Tecnologie e Salute, Istituto Superiore di Sanita and INFN, Rome (Italy); Lovik, I. [Dipartimento di Fisiopatologia dell' Universita and INFN, Florence (Italy); Onori, S. [Dipartimento di Tecnologie e Salute, Istituto Superiore di Sanita and INFN, Rome (Italy); Raffaele, L. [Laboratori Nazionali del SUD, INFN, Catania (Italy); Sciortino, S. [Dipartimento di Energetica dell' Universita and INFN, Florence (Italy)

    2005-10-21

    This paper reviews the main results of the study, carried out in the framework of the Italian National Institute of Nuclear Physics (INFN, Istituto Nazionale di Fisica Nucleare) projects, namely CANDIDO and CONRAD, on natural and synthetic diamond-based dosimeters for clinical radiotherapy. Characteristics of diamond such as radiation hardness, high sensitivity, tissue equivalence, etc., make this material interesting for dosimetry applications. For some years, natural diamonds have been commercially available for on-line radiotherapy dosimetry. Nevertheless, recent developments in the 'Chemical Vapour Deposition' (CVD) technique have addressed the attention on synthetic samples that potentially could be grown at low cost and with features suitable for dosimetric use. Several samples, differently grown and with different electrical contacts, have been compared by measuring their current response during irradiation with high-energy photon, electron and proton beams. Properties of dosimetric interest such as linearity, pre-irradiation dose, dose rate dependence, stability and rise time have been investigated. The results obtained so far within the INFN collaboration demonstrate the suitability of natural diamond detectors for many radiotherapy applications and the great potential of CVD diamond-based devices even though, at present, the commercial natural diamond dosimeters have a better behaviour with respect to the synthetic samples. Further efforts have to be made mainly to improve the dynamic of response and performance stability.

  20. 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.

  1. Diamond dosimetry: Outcomes of the CANDIDO and CONRAD INFN projects

    Science.gov (United States)

    Bucciolini, M.; Borchi, E.; Bruzzi, M.; Casati, M.; Cirrone, P.; Cuttone, G.; De Angelis, C.; Lovik, I.; Onori, S.; Raffaele, L.; Sciortino, S.

    2005-10-01

    This paper reviews the main results of the study, carried out in the framework of the Italian National Institute of Nuclear Physics (INFN, Istituto Nazionale di Fisica Nucleare) projects, namely CANDIDO and CONRAD, on natural and synthetic diamond-based dosimeters for clinical radiotherapy. Characteristics of diamond such as radiation hardness, high sensitivity, tissue equivalence, etc., make this material interesting for dosimetry applications. For some years, natural diamonds have been commercially available for on-line radiotherapy dosimetry. Nevertheless, recent developments in the "Chemical Vapour Deposition" (CVD) technique have addressed the attention on synthetic samples that potentially could be grown at low cost and with features suitable for dosimetric use. Several samples, differently grown and with different electrical contacts, have been compared by measuring their current response during irradiation with high-energy photon, electron and proton beams. Properties of dosimetric interest such as linearity, pre-irradiation dose, dose rate dependence, stability and rise time have been investigated. The results obtained so far within the INFN collaboration demonstrate the suitability of natural diamond detectors for many radiotherapy applications and the great potential of CVD diamond-based devices even though, at present, the commercial natural diamond dosimeters have a better behaviour with respect to the synthetic samples. Further efforts have to be made mainly to improve the dynamic of response and performance stability.

  2. Microstructural Characterisation and Wear Behaviour of Diamond Composite Materials

    Directory of Open Access Journals (Sweden)

    Xing S. Li

    2010-02-01

    Full Text Available Since the initial research leading to the production of diamond composite materials, there have been several important developments leading to significant improvements in the properties of these superhard composite materials. Apart from the fact that diamonds, whether originating from natural resources or synthesised commercially, are the hardest and most wear-resistant materials commonly available, there are other mechanical properties that limit their industrial application. These include the low fracture toughness and low impact strength of diamond. By incorporating a range of binder phases into the sintering production process of these composites, these critically important properties have been radically improved. These new composites can withstand much higher operating temperatures without markedly reducing their strength and wear resistance. Further innovative steps are now being made to improve the properties of diamond composites by reducing grain and particle sizes into the nano range. This review will cover recent developments in diamond composite materials with special emphasis on microstructural characterisation. The results of such studies should assist in the design of new, innovative diamond tools as well as leading to radical improvements in the productivity of cutting, drilling and sawing operations in the exploration, mining, civil construction and manufacturing industries.

  3. 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.

  4. Precision truing of diamond wheel with sharp edge

    Science.gov (United States)

    Ge, Cheng; Guo, Bing; Zhao, QIngliang; Chen, Bing; Wang, Jinhu

    2014-08-01

    Diamond wheel with sharp edge has small contour structures, which can lead to fast wear of wheel in the grinding process. Traditional truing methods are hard to apply to this kind of wheels. Therefore, as for the difficulty of precision truing of diamond wheel with sharp edge, the novel methods for resin and metal bonded diamond wheels with sharp edge are presented, respectively. In this experiment, a conditioning procedure with rare metal alloy block Ta was used to true the resin bonded diamond grinding wheel and in the same way Nb alloy block was utilized to complete rough truing of metal bonded diamond grinding wheel. Then a CNC truing technique with rotational green carbide (GC) truing stick was applied to precise truing of metal bonded diamond grinding wheel. Methods mentioned above were measured in order to evaluate the performance of truing. Geometric features of the wheel sharp edge were duplicated on the organic glass (PMMA) in order to measure and calculate the radius of the sharp edge. The edge radius of trued resin bonded wheel and metal bonded wheel is perceived as an important assessment. The experiments results revealed that the edge radius of 12.45μm for the resin bonded wheel and the edge radius of 30.17μm for the metal bonded wheel could be achieved.

  5. PREFACE Surface Modifications of Diamond and Related Materials (Session D, E-MRS Spring Meeting)

    Science.gov (United States)

    Nebel, Christoph E.

    2010-11-01

    This special issue contains selected papers which were presented at the E-MRS Symposium BIOMATERIALS, SENSORS & SURFACES, D: 'Surface modifications of diamond and related materials' which was held on 7-9 June 2010 in Strasbourg (France). With about 54 oral and poster presentations given from teams all over the world it was a very interesting, dense and lively meeting. The symposium focused on chemical modifications applied to graft surfaces of diamond, nano-diamond particles, diamond-like carbon, graphene, graphite and carbon nano-tubes with linker molecular layers for realization of bio-sensors, bio-markers, separation techniques, and switchable chemical links. Presented techniques span spontaneous bonding to photo-chemical attachment, electrochemical modifications, to Suzuki-coupling of aryl molecules. Special attention was drawn to mechanisms driving bonding kinetics such as electron transfer reactions, hydrogen cleavage reactions by nucleophilic molecules and growths schemas which vary from correlated two-dimensional chain reactions to three-dimensional cross polymerization. Hydrogen terminations, surface defects, surface roughness and atomic arrangements of surface carbon atoms were of interest to elucidate bonding mechanisms. In addition, bonding stability, either of linker molecules or of complex functionalized surfaces with DNA, proteins and enzymes was discussed by several speakers as well as details of the electronic interfaces between solid transducers and bio-layers. Here the characterization of surface and interface defect densities, of Fermi level pinning and of electron transfer rates was a major topic. Miniaturization of sensor area and application of new detection schemas was discussed. Diamond nano-particles which are increasingly used as biomarkers in drug delivery experiments also attracted attention. The organizers express our gratitude to the international members of the scientific committee who actively contributed to ensure an attractive

  6. Limnology of Eifel maar lakes

    National Research Council Canada - National Science Library

    Scharf, Burkhard W; Björk, Sven

    1992-01-01

    ... : Species composition & seasonal periodicity - Qualitative & quantitative investigations on cladoceran zooplankton of oligotrophic maar lakes - Population dynamics of pelagic copepods in maar lakes - Population dynamics...

  7. Water-quality and lake-stage data for Wisconsin lakes, water years 2012–2013

    Science.gov (United States)

    Manteufel, S. Bridgett; Robertson, Dale M.

    2017-05-25

    the Wisconsin Water Science Center’s Lakes Program is found at http://wi.water.usgs.gov/lakes/index.html and http://wi.water.usgs.gov/projects/index.html.

  8. Water-quality and lake-stage data for Wisconsin lakes, water year 2014

    Science.gov (United States)

    Manteufel, S. Bridgett; Robertson, Dale M.

    2017-05-25

    about the Wisconsin Water Science Center’s Lakes Program is found at http://wi.water.usgs.gov/lakes/index.html and http://wi.water.usgs.gov/projects/index.html.

  9. Early fire history near Papineau lake, Ontario

    Science.gov (United States)

    Daniel C. Dey; Richard P. Guyette

    1996-01-01

    Research that defines the role of fire in upland red oak-pine ecosystems in central Ontario is being conducted by the Great Lakes-St. Lawrence Silviculture program. Site-specific fire histories are being developed that document fire frequency, fire behavior, fire effects on forest regeneration and grwoth, and the influnce of human activites on fire disturbances. This...

  10. Global Change in the Great Lakes: Scenarios.

    Science.gov (United States)

    Garrison, Barbara K., Ed.; Rosser, Arrye R., Ed.

    The Ohio Sea Grant Education Program has produced this series of publications designed to help people understand how global change may affect the Great Lakes region. The possible implications of global change for this region of the world are explained in the hope that policymakers and individuals will be more inclined to make responsible decisions…

  11. Lake Erie Water Level Study. Main Report.

    Science.gov (United States)

    1981-07-01

    from thermal installations (oil, fossil , or nuclear fueled), maximum utilization of the hydroelectric power capacity is economically and environmentally...the factors affecting lake level fluctuations and the study methodology. A popular misconception is that artificial means currently exist which...public information program to eliminate the confusion and misconceptions that currently exist. 3. COASTAL ZONE MANAGEMENT PRACTICES SHOULD BE ENCOURAGED

  12. Water Resources Research Program. Transport of oily pollutants in the coastal waters of Lake Michigan. An application of rare earth tracers

    Energy Technology Data Exchange (ETDEWEB)

    McCown, D. L.; Saunders, K. D.; Allender, J. H.; Ditmars, J. D.; Harrison, W.

    1978-11-01

    An experimental method was developed to tag and to trace oily pollutants in fresh water environments. The use of two rare earth element tags (Dy and Sm) permitted simultaneous tracing of small oil spills at the water surface and of the underlying water. Neutron activation analysis was used to determine the tracer concentrations in numerous, small water samples collected from a moving boat. The method was applied in two field experiments with simulated oily pollutants in the Indiana Harbor Canal (IHC). Tagged oily pollutants and IHC waters were traced under both floating- and sinking-plume conditions. Floating-plume results indicated that oily waste artificially mixed downward by a ship did not resurface, no differences were seen in the movement of the oily waste and the underlying water, and mixing coefficients for tagged oil and water were similar to those measured by others on the Great Lakes. Sinking-plume results gave unequivocal evidence of the intake of IHC effluent at Chicago's South Water Filtration Plant and indicated partitioning of the oily wastes and water. Simple dilution estimates for the sinking plume were supported by the tracer data and similar estimates indicated plume center-line dilution ratios for the entire IHC effluent at the water intakes could be as low as 2.8.

  13. Synthesis and characterization of diamond microcrystals and nanorods deposited by hot cathode direct current plasma chemical vapor deposition method

    NARCIS (Netherlands)

    Zeng, L.; Peng, H.; Wang, W.; Chen, Y.; Lei, D.; Qi, W.; Liang, J.; Zhao, J.; Kong, X.; Zhang, H.

    2008-01-01

    (111) diamond microcrystals and (100) diamond microcrystals and nanorods were synthesized on Si substrate by hot cathode direct current plasma chemical vapor deposition method. The morphology, structure, and optical properties of the diamond films were characterized by scanning electron microscopy,

  14. Comparison of the oxygen reduction on a diamond powder supported electrocatalysts and Pani modified diamond powder supported electrocatalysts

    Energy Technology Data Exchange (ETDEWEB)

    Ozenler, S.S.; Kadirgan, F. [Istanbul Technical Univ., Istanbul (Turkey). Dept. of Chemistry

    2006-07-01

    A study was conducted in which a catalyst was prepared based on the nanostructured Mo{sub x}Ru{sub y}Se{sub z} compounds was prepared by thermolysis of their carbonyl compounds in organic solvents. The activities towards the oxygen reduction of diamond powder supported Mo{sub x}Ru{sub y}Se{sub z} based electrodes and Polyaniline (Pani) modified diamond powder supported Mo{sub x}Ru{sub y}Se{sub z} based cathode electrodes for proton exchange membrane fuel cells (PEMFC) were then compared by electrochemical methods on carbon paper and carbon textile. The synthesized catalyst was supported either by nano diamond powder or Pani modified nano diamond powder. Polyaniline modified electrodes were fabricated electrochemically on diamond powder supported electrodes. The oxygen reduction activity and methanol tolerance of both electrodes was compared with platinum electrode at elevated temperatures. The oxygen reduction reaction rate was found to be much higher with the polyaniline coated diamond powder matrix. 5 refs.

  15. Quantifying strain birefringence halos around inclusions in diamond

    Science.gov (United States)

    Howell, D.; Wood, I. G.; Dobson, D. P.; Jones, A. P.; Nasdala, L.; Harris, J. W.

    2010-11-01

    The pressure and temperature conditions of formation of natural diamond can be estimated by measuring the residual stress that an inclusion remains under within a diamond. Raman spectroscopy has been the most commonly used technique for determining this stress by utilising pressure-sensitive peak shifts in the Raman spectrum of both the inclusion and the diamond host. Here, we present a new approach to measure the residual stress using quantitative analysis of the birefringence induced in the diamond. As the analysis of stress-induced birefringence is very different from that of normal birefringence, an analytical model is developed that relates the spherical inclusion size, R i, host diamond thickness, L, and measured value of birefringence at the edge of the inclusion, Updelta n(R_{text{i}} )_{text{av}} , to the peak value of birefringence that has been encountered; to first order Updelta n_{text{pk}} = (3/4)(L/R_{text{i}} ) Updelta n(R_{text{i}} )_{text{av}} . From this birefringence, the remnant pressure ( P i) can be calculated using the photoelastic relationship Updelta n_{text{pk}} = - (3/4)n3 q_{text{iso}} P_{text{i}} , where q iso is a piezo-optical coefficient, which can be assumed to be independent of crystallographic orientation, and n is the refractive index of the diamond. This model has been used in combination with quantitative birefringence analysis with a MetriPol system and compared to the results from both Raman point and 2D mapping analysis for a garnet inclusion in a diamond from the Udachnaya mine (Russia) and coesite inclusions in a diamond from the Finsch mine (South Africa). The birefringence model and analysis gave a remnant pressure of 0.53 ± 0.01 GPa for the garnet inclusion, from which a source pressure was calculated as 5.7 GPa at 1,175°C (temperature obtained from IR analysis of the diamond host). The Raman techniques could not be applied quantitatively to this sample to support the birefringence model; they were, however, applied

  16. Laser-induced multi-energy processing in diamond growth

    Science.gov (United States)

    Xie, Zhiqiang

    Laser-induced multi-energy processing (MEP) introduces resonant vibrational excitations of precursor molecules to conventional chemical vapor deposition methods for material synthesis. In this study, efforts were extended to explore the capability of resonant vibrational excitations for promotion of energy efficiency in chemical reactions, for enhancement of diamond deposition, and for control of chemical reactions. The research project mainly focused on resonant vibrational excitations of precursor molecules using lasers in combustion flame deposition of diamond, which led to: 1) promotion of chemical reactions; 2) enhancement of diamond growth with higher growth rate and better crystallizations; 3) steering of chemical reactions which lead to preferential growth of {100}-oriented diamond films and crystals; and 4) mode-selective excitations of precursor molecules toward bond-selective control of chemical reactions. Diamond films and crystals were deposited in open air by combustion flame deposition through resonant vibrational excitations of precursor molecules, including ethylene (C2H4) and propylene (C3H 6). A kilowatt wavelength-tunable CO2 laser with spectral range from 9.2 to 10.9 microm was tuned to match vibrational modes of the precursor molecules. Resonant vibrational excitations of these molecules were achieved with high energy efficiency as compared with excitations using a common CO2 laser (fixed wavelength at 10.591microm). With resonant vibrational excitations, the diamond growth rate was increased; diamond quality was promoted; diamond crystals with lengths up to 5 mm were deposited in open air; preferential growth of {100}-oriented diamond films and single crystals was achieved; mode-selective excitations of precursor molecules were investigated toward control of chemical reactions. Optical emission spectroscopy (OES), mass spectrometry (MS), and molecular dynamic simulations were conducted to obtain an in-depth understanding of the resonant

  17. Great Salt Lake, Utah

    Science.gov (United States)

    Stephens, Doyle W.; Gardner, Joe F.

    1999-01-01

    This document is intended as a source of general information and facts about Great Salt Lake, Utah. This U.S. Geological Survey information sheet answers frequently asked questions about Great Salt Lake. Topics include: History, salinity, brine shrimp, brine flies, migratory birds, and recreation. Great Salt Lake, the shrunken remnant of prehistoric Lake Bonneville, has no outlet. Dissolved salts accumulate in the lake by evaporation. Salinity south of the causeway has ranged from 6 percent to 27 percent over a period of 22 years (2 to 7 times saltier than the ocean). The high salinity supports a mineral industry that extracts about 2 million tons of salt from the lake each year. The aquatic ecosystem consists of more than 30 species of organisms. Harvest of its best-known species, the brine shrimp, annually supplies millions of pounds of food for the aquaculture industry worldwide. The lake is used extensively by millions of migratory and nesting birds and is a place of solitude for people. All this occurs in a lake that is located at the bottom of a 35,000-square-mile drainage basin that has a human population of more than 1.5 million.

  18. Great Lakes: Great Gardening.

    Science.gov (United States)

    New York Sea Grant Inst., Albany, NY.

    This folder contains 12 fact sheets designed to improve the quality of gardens near the Great Lakes. The titles are: (1) "Your Garden and the Great Lakes"; (2) "Organic Gardening"; (3) "Fruit and Vegetable Gardening"; (4) "Composting Yard Wastes"; (5) "Herbicides and Water Quality"; (6)…

  19. Evaporation From Lake Superior

    Science.gov (United States)

    Spence, C.; Blanken, P.; Hedstrom, N.; Leshkevich, G.; Fortin, V.; Charpentier, D.; Haywood, H.

    2009-05-01

    Evaporation is a critical component of the water balance of each of the Laurentian Great Lakes, and understanding the magnitude and physical controls of evaporative water losses are important for several reasons. Recently, low water levels in Lakes Superior and Michigan/Huron have had socioeconomic, ecological, and even meteorological impacts (e.g. water quality and quantity, transportation, invasive species, recreation, etc.). The recent low water levels may be due to increased evaporation, but this is not known as operational evaporation estimates are currently calculated as the residual of water or heat budgets. Perhaps surprisingly, almost nothing is known about evaporation dynamics from Lake Superior and few direct measurements of evaporation have been made from any of the Laurentian Great Lakes. This research is the first to attempt to directly measure evaporation from Lake Superior by deploying eddy covariance instrumentation. Results of evaporation rates, their patterns and controlling mechanisms will be presented. The direct measurements of evaporation are used with concurrent satellite and climate model data to extrapolate evaporation measurements across the entire lake. This knowledge could improve predictions of how climate change may impact the lake's water budget and subsequently how the water in the lake is managed.

  20. Identifying and Leveraging Trust as a Key Element in the Development, Implementation and Sustainment of the Salt Lake City Fire Department’s Intelligence Program

    Science.gov (United States)

    2014-09-01

    Disentanglement and Protest Deterrence Training, which consisted of didactic and tactical training programs and had built several working relationships with...This program also includes joint training, both didactic and tactile, taking this network development to a higher level by improving the mutual...the book , From Good to Great, Jim Collins wrote a chapter called, First Who…Then What.152 The significant finding of his research on the core of

  1. Lake Superior revisited 1984

    Science.gov (United States)

    MacCallum, Wayne R.; Selgeby, James H.

    1987-01-01

    The Lake Superior fish community has changed substantially since the early 1960s, when control of the sea lamprey (Petromyzon marinus) became effective. Self-reproducing stocks of lake trout (Salvelinus namaycush) have been reestablished in many inshore areas, although they have not yet reached pre-sea lamprey abundance; offshore lake trout are probably at or near pre-sea lamprey abundance. Stocks of lake whitefish (Coregonus clupeaformis) appear to have fully recovered; commercial catches are at or above historical levels. Lake herring (Coregonus artedii) are recovering rapidly in U.S. waters and are abundant in western Canadian waters. The population of rainbow smelt (Osmerus mordax), which declined in the 1970s, is recovering. Pacific salmon (Oncorhynchus) are becoming more abundant as a result of increased stocking in U.S. waters and are reproducing in most suitable tributaries; they have become significant in anglers' creels.

  2. EXPLOITATIVE DESTRUCTION FEATURES FOR DETONATION ULTRADISPERSED DIAMONDS OF INITIAL METALLIC PROTECTION FOR ABRASIVE POWDER GRAINS TO DIAMOND-SPARK GRINDING TOOLS

    Directory of Open Access Journals (Sweden)

    Yury GUTSALENKO

    2015-05-01

    Full Text Available The problem of exploitation of diamond grinding wheels with metal coating for their grains including detonation ultra-dispersed diamonds to increase functional reliability to maintain the initial integrity of grains in the pressing and sintering of diamond-metal composites in the tool production is considered. One problem is that the presence of detonation ultra-dispersed diamonds in the grain metal coating of diamond powders not only improves the coating functional reliability in protection from destruction in the subsequent pressing and sintering in the production tool, but also resistance of such coating to the opening of the diamond cutting basis of the grains on the grinding wheel working surface that come into working contact with the material being processed. An analysis of the features of an effective exploitative destruction of detonation ultra-dispersed diamonds in the metal coating using electric current in the tool of the diamondspark grinding processes is presented.

  3. Lake metabolism scales with lake morphometry and catchment conditions

    DEFF Research Database (Denmark)

    Stæhr, Peter Anton; Båstrup-Spohr, Lars; Jensen, Kaj Sand

    2012-01-01

    We used a comparative data set for 25 lakes in Denmark sampled during summer to explore the influence of lake morphometry, catchment conditions, light availability and nutrient input on lake metabolism. We found that (1) gross primary production (GPP) and community respiration (R) decline with la...... in lake morphometry and catchment conditions when comparing metabolic responses of lakes to human impacts....... area, water depth and drainage ratio, and increase with algal biomass (Chl), dissolved organic carbon (DOC) and total phosphorus (TP); (2) all lakes, especially small with less incident light, and forest lakes with high DOC, have negative net ecosystem production (NEP

  4. Diamond-Blackfan anemia, ribosome and erythropoiesis.

    Science.gov (United States)

    Da Costa, L; Moniz, H; Simansour, M; Tchernia, G; Mohandas, N; Leblanc, T

    2010-09-01

    Diamond-Blackfan anemia is a rare inherited bone marrow failure syndrome (five to seven cases per million live births) characterized by an aregenerative, usually macrocytic anemia with an absence or less than 5% of erythroid precursors (erythroblastopenia) in an otherwise normal bone marrow. The platelet and the white cell counts are usually normal but neutropenia, thrombopenia or thrombocytosis have been noted at diagnosis. In 40 to 50% of DBA patients, congenital abnormalities mostly in the cephalic area and in thumbs and upper limbs have been described. Recent analysis did show a phenotype/genotype correlation. Congenital erythroblastopenia of DBA is the first human disease identified to result from defects in ribosomal biogenesis. The first ribosomal gene involved in DBA, ribosomal protein (RP) gene S19 (RPS19 gene), was identified in 1999. Subsequently, mutations in 12 other RP genes out of a total of 78 RP genes have been identified in DBA. All RP gene mutations described to date are heterozygous and dominant inheritance has been documented in 40 to 45% of affected individuals. As RP mutations are yet to be identified in approximately 50% of DBA cases, it is likely that other yet to be identified genes involved in ribosomal biogenesis or other pathways may be responsible for DBA phenotype. Copyright 2010 Elsevier Masson SAS. All rights reserved.

  5. Diamond-coated ATR prism for infrared absorption spectroscopy of surface-modified diamond nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Remes, Z., E-mail: remes@fzu.cz [Institute of Physics of the ASCR, v.v.i., Cukrovarnicka 10, Praha 6 (Czech Republic); Kozak, H.; Rezek, B.; Ukraintsev, E.; Babchenko, O.; Kromka, A. [Institute of Physics of the ASCR, v.v.i., Cukrovarnicka 10, Praha 6 (Czech Republic); Girard, H.A.; Arnault, J.-C.; Bergonzo, P. [CEA, LIST, Diamond Sensors Laboratory, F-91191 Gif-sur-Yvette (France)

    2013-04-01

    Linear antenna microwave chemical vapor deposition process was used to homogeneously coat a 7 cm long silicon prism by 85 nm thin nanocrystalline diamond (NCD) layer. To show the advantages of the NCD-coated prism for attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR) of nanoparticles, we apply diamond nanoparticles (DNPs) of 5 nm nominal size with various surface modifications by a drop-casting of their methanol dispersions. ATR-FTIR spectra of as-received, air-annealed, plasma-oxidized, and plasma-hydrogenated DNPs were measured in the 4000–1500 cm{sup −1} spectral range. The spectra show high spectral resolution, high sensitivity to specific DNP surface moieties, and repeatability. The NCD coating provides mechanical protection against scratching and chemical stability of the surface. Moreover, unlike on bare Si surface, NCD hydrophilic properties enable optically homogeneous coverage by DNPs with some aggregation on submicron scale as evidenced by scanning electron microscopy and atomic force microscopy. Compared to transmission FTIR regime with KBr pellets, direct and uniform deposition of DNPs on NCD-ATR prism significantly simplifies and speeds up the analysis (from days to minutes). We discuss prospects for in situ monitoring of surface modifications and molecular grafting.

  6. Investigation of the shape transferability of nanoscale multi-tip diamond tools in the diamond turning of nanostructures

    Science.gov (United States)

    Luo, Xichun; Tong, Zhen; Liang, Yingchun

    2014-12-01

    In this article, the shape transferability of using nanoscale multi-tip diamond tools in the diamond turning for scale-up manufacturing of nanostructures has been demonstrated. Atomistic multi-tip diamond tool models were built with different tool geometries in terms of the difference in the tip cross-sectional shape, tip angle, and the feature of tool tip configuration, to determine their effect on the applied forces and the machined nano-groove geometries. The quality of machined nanostructures was characterized by the thickness of the deformed layers and the dimensional accuracy achieved. Simulation results show that diamond turning using nanoscale multi-tip tools offers tremendous shape transferability in machining nanostructures. Both periodic and non-periodic nano-grooves with different cross-sectional shapes can be successfully fabricated using the multi-tip tools. A hypothesis of minimum designed ratio of tool tip distance to tip base width (L/Wf) of the nanoscale multi-tip diamond tool for the high precision machining of nanostructures was proposed based on the analytical study of the quality of the nanostructures fabricated using different types of the multi-tip tools. Nanometric cutting trials using nanoscale multi-tip diamond tools (different in L/Wf) fabricated by focused ion beam (FIB) were then conducted to verify the hypothesis. The investigations done in this work imply the potential of using the nanoscale multi-tip diamond tool for the deterministic fabrication of period and non-periodic nanostructures, which opens up the feasibility of using the process as a versatile manufacturing technique in nanotechnology.

  7. Novel phase of carbon, ferromagnetism, and conversion into diamond

    Energy Technology Data Exchange (ETDEWEB)

    Narayan, Jagdish, E-mail: narayan@ncsu.edu; Bhaumik, Anagh [Department of Materials Science and Engineering, Centennial Campus, North Carolina State University, Raleigh, North Carolina 27695-7907 (United States)

    2015-12-07

    We report the discovery of a new phase of carbon (referred to as Q-carbon) and address fundamental issues related to direct conversion of carbon into diamond at ambient temperatures and pressures in air without any need for catalyst and presence of hydrogen. The Q-carbon is formed as result of quenching from super undercooled state by using high-power nanosecond laser pulses. We discuss the equilibrium phase diagram (P vs. T) of carbon and show that by rapid quenching kinetics can shift thermodynamic graphite/diamond/liquid carbon triple point from 5000 K/12 GPa to super undercooled carbon at atmospheric pressure in air. It is shown that nanosecond laser heating of diamond-like amorphous carbon on sapphire, glass, and polymer substrates can be confined to melt carbon in a super undercooled state. By quenching the carbon from the super undercooled state, we have created a new state of carbon (Q-carbon) from which nanodiamond, microdiamond, microneedles, and single-crystal thin films are formed depending upon the nucleation and growth times allowed for diamond formation. The Q-carbon quenched from liquid is a new state of solid carbon with a higher mass density than amorphous carbon and a mixture of mostly fourfold sp{sup 3} (75%–85%) with the rest being threefold sp{sup 2} bonded carbon (with distinct entropy). It is expected to have new and improved mechanical hardness, electrical conductivity, chemical, and physical properties, including room-temperature ferromagnetism (RTFM) and enhanced field emission. Here we present interesting results on RTFM, enhanced electrical conductivity and surface potential of Q-carbon to emphasize its unique properties. The Q-carbon exhibits robust bulk ferromagnetism with estimated Curie temperature of about 500 K and saturation magnetization value of 20 emu g{sup −1}. From the Q-carbon, diamond phase is nucleated and a variety of micro- and nanostructures and large-area single-crystal diamond sheets are grown by allowing

  8. 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.

  9. Brazing diamond grits onto a steel substrate using copper alloys as the filler metals

    Science.gov (United States)

    Chen, S.-M.; Lin, S.-T.

    1996-12-01

    Surface-set diamond tools were fabricated by an active metal brazing process, using bronze (Cu-8.9Sn) powder and 316L stainless steel powder mixed to various ratios as the braze filler metals. The diamond grits were brazed onto a steel substrate at 1050 °C for 30 min in a dry hydrogen atmosphere. After brazing practice, an intermediate layer rich in chromium formed between the braze filler metal and diamond. A braze filler metal composed of 70 wt % bronze powder and 30 wt % stainless steel powder was found to be optimum in that the diamond grits were strongly impregnated in the filler metal by both mechanical and chemical types of holding. The diamond tools thus fabricated performed better than conventional nickel-plated diamond tools. In service, the braze filler metal wore at almost the same rate as the diamond grits, and no pullout of diamond grits or peeling of the filler metal layer took place.

  10. Yellowstone Lake Nanoarchaeota

    Directory of Open Access Journals (Sweden)

    Scott eClingenpeel

    2013-09-01

    Full Text Available Considerable Nanoarchaeota novelty and diversity were encountered in Yellowstone Lake, Yellowstone National Park, where sampling targeted lake floor hydrothermal vent fluids, streamers and sediments associated with these vents, and in planktonic photic zones in three different regions of the lake. Significant homonucleotide repeats (HR were observed in pyrosequence reads and in near full-length Sanger sequences, averaging 112 HR per 1,349 bp clone and could confound diversity estimates derived from pyrosequencing, resulting in false nucleotide insertions or deletions (indels. However, Sanger sequencing of two different sets of PCR clones (110 bp, 1349 bp demonstrated that at least some of these indels are real. The majority of the Nanoarchaeota PCR amplicons were vent associated; however, curiously, one relatively small Nanoarchaeota OTU (70 pyrosequencing reads was only found in photic zone water samples obtained from a region of the lake furthest removed from the hydrothermal regions of the lake. Extensive pyrosequencing failed to demonstrate the presence of an Ignicoccus lineage in this lake, suggesting the Nanoarchaeota in this environment are associated with novel Archaea hosts. Defined phylogroups based on near full-length PCR clones document the significant Nanoarchaeota 16S rRNA gene diversity in this lake and firmly establish a terrestrial clade distinct from the marine Nanoarcheota as well as from other geographical locations.

  11. Yellowstone lake nanoarchaeota.

    Science.gov (United States)

    Clingenpeel, Scott; Kan, Jinjun; Macur, Richard E; Woyke, Tanja; Lovalvo, Dave; Varley, John; Inskeep, William P; Nealson, Kenneth; McDermott, Timothy R

    2013-01-01

    Considerable Nanoarchaeota novelty and diversity were encountered in Yellowstone Lake, Yellowstone National Park (YNP), where sampling targeted lake floor hydrothermal vent fluids, streamers and sediments associated with these vents, and in planktonic photic zones in three different regions of the lake. Significant homonucleotide repeats (HR) were observed in pyrosequence reads and in near full-length Sanger sequences, averaging 112 HR per 1349 bp clone and could confound diversity estimates derived from pyrosequencing, resulting in false nucleotide insertions or deletions (indels). However, Sanger sequencing of two different sets of PCR clones (110 bp, 1349 bp) demonstrated that at least some of these indels are real. The majority of the Nanoarchaeota PCR amplicons were vent associated; however, curiously, one relatively small Nanoarchaeota OTU (71 pyrosequencing reads) was only found in photic zone water samples obtained from a region of the lake furthest removed from the hydrothermal regions of the lake. Extensive pyrosequencing failed to demonstrate the presence of an Ignicoccus lineage in this lake, suggesting the Nanoarchaeota in this environment are associated with novel Archaea hosts. Defined phylogroups based on near full-length PCR clones document the significant Nanoarchaeota 16S rRNA gene diversity in this lake and firmly establish a terrestrial clade distinct from the marine Nanoarcheota as well as from other geographical locations.

  12. Supplementary Environmental Baseline Studies and Evaluation of the St. Mary’s River 1980. Great Lakes-St. Lawrence Seaway Navigation Season Extension Program

    Science.gov (United States)

    1981-07-01

    TIC FILE CO" piological Services Program FWSWOBS 80182.1 JULY 1981 SSUPPLEMENTARY ENVIRONMENTAL (N BASELINE STUDIES & EVALUATION I! OF THE ST. MARY’S...Iowa darter 4 4 Johnny darter 704 7 7 718 Logperch 48 9 1 58 Yellow perch 135 185 154 5 479 Wa] leye 46 9 9 64 Mottled sculpin 289 6 295 Slimy sculpin

  13. Focused ion beam fabrication of boron-doped diamond ultramicroelectrodes.

    Science.gov (United States)

    Hu, Jingping; Holt, Katherine B; Foord, John S

    2009-07-15

    The fabrication of ultramicroelectrodes (UMEs) for analytical electrochemical applications has been explored, using boron-doped diamond as the active electrode material in an insulating coating formed by deposition of electrophoretic paint. Because of the rough nature of the diamond film, the property of such coatings that is normally exploited in the fabrication of UMEs, namely the tendency to retract automatically from sharp protrusions, cannot be used in the present instance. Instead focused ion beam (FIB) sputtering was employed to controllably produce UMEs with well-defined geometry, critical dimension of a few micrometers, and very thin insulating coatings. If the FIB machining is carried out at normal incidence to the diamond electrode surface, significant ion beam damage reduces the yield of successful electrodes. However, if a parallel machining geometry is employed, high yields of ultramicroelectrodes with a flat disk geometry can be obtained very reliably. The electrochemical properties of diamond UMEs are characterized. They show much lower background currents than the equivalent Pt or carbon fiber electrodes but more varied electrochemical response than macroscopic diamond electrodes.

  14. 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.

  15. Chemical vapour deposition of diamond coatings onto molybdenum dental tools

    Science.gov (United States)

    Amar, M.; Ahmed, W.; Sein, H.; Jones, A. N.; Rego, C. A.

    2003-10-01

    The growth of polycrystalline diamond films onto molybdenum rods and dental burrs by using a new hot filament chemical vapour deposition (CVD) system has been investigated. Negative dc bias voltage relative to the filament was applied to the molybdenum substrate prior to deposition. This led to much improved film adhesion and increased nucleation density. There was a factor of four improvement in the adhesive force from 20 to 80 N when a bias voltage of -300 V was employed to the substrate. The CVD coated molybdenum dental burr was found to give much improved performance and lifetime compared to the conventional sintered diamond burr. The CVD diamond burr showed no signs of deterioration even after 1000 operations whereas the conventional sintered diamond burrs were ineffective after between 30 and 60 operations. This represents a 30-fold improvement when CVD is applied. CVD diamond growth onto dental burrs has the potential for replacing exciting technology by achieving better performance and lifetime in a cost-effective manner.

  16. CVD Diamond Sensors In Detectors For High Energy Physics

    CERN Document Server

    AUTHOR|(INSPIRE)INSPIRE-00334150; Trischuk, William

    At the end of the next decade an upgrade of the Large Hadron Collider (LHC) to High Luminosity LHC (HL-LHC) is planned which requires the development of new radiation tolerant sensor technology. Diamond is an interesting material for use as a particle detector in high radiation environments. The large band gap ($5.47\\,\\text{eV}$) and the large displacement energy suggest that diamond is a radiation tolerant detector material. In this Thesis the capability of Chemical Vapor Deposition (CVD) diamond as such a sensor technology is investigated. The radiation damage constant for $800\\,\\text{MeV}$ protons is measured using single crystalline CVD (scCVD) and polycrystalline CVD (pCVD) diamonds irradiated to particle fluences up to $12 \\times 10^{15}\\,\\text{p/cm}^2$. In addition the signal response of a pCVD diamond detector after an irradiation to $12 \\times 10^{15}\\,\\text{p/cm}^2$ is investigated to determine if such a detector can be operated efficiently in the expected HL-LHC environment. By using electrodes em...

  17. Nanosecond formation of diamond and lonsdaleite by shock compression of graphite

    OpenAIRE

    Kraus, D.; Ravasio, A.; Gauthier, M.; Gericke, D. O.; Vorberger, J.; Frydrych, S.; Helfrich, J.; Fletcher, L. B.; Schaumann, G.; Nagler, B.; Barbrel, B.; Bachmann, B.; Gamboa, E. J.; G?de, S.; Granados, E.

    2016-01-01

    The shock-induced transition from graphite to diamond has been of great scientific and technological interest since the discovery of microscopic diamonds in remnants of explosively driven graphite. Furthermore, shock synthesis of diamond and lonsdaleite, a speculative hexagonal carbon polymorph with unique hardness, is expected to happen during violent meteor impacts. Here, we show unprecedented in situ X-ray diffraction measurements of diamond formation on nanosecond timescales by shock comp...

  18. All-diamond functional surface micro-electrode arrays for brain-slice neural analysis

    OpenAIRE

    Vahidpour, Farnoosh; Curley, Lowry; Biró, István; McDonald, Matthew; Croux, Dieter; POBEDINSKAS, Paulius; Haenen, Ken; Giugliano, Michele; Zivcova, Zuzana Vlckova; Kavan, Ladislav; Nesladek, Milos

    2017-01-01

    Abstract: Diamond-based microelectrode arrays were fabricated by using nanocrystalline diamond as an insulating layer and conductive boron-doped in order to used them for analysis of brain cortical slices. MEA surface is solely composed of diamond, exposed to the cells. The impedance measurements showed negligible cross-talk between neighbouring diamond microelectrodes. Local field potentials related to neural signals were then successfully recorded from pharmacologically disinhibited rat cor...

  19. Dynamic compression of synthetic diamond windows (final report for LDRD project 93531).

    Energy Technology Data Exchange (ETDEWEB)

    Dolan, Daniel H.,

    2008-09-01

    Diamond is an attractive dynamic compression window for many reasons: high elastic limit,large mechanical impedance, and broad transparency range. Natural diamonds, however, aretoo expensive to be used in destructive experiments. Chemical vapor deposition techniquesare now able to produce large single-crystal windows, opening up many potential dynamiccompression applications. This project studied the behavior of synthetic diamond undershock wave compression. The results suggest that synthetic diamond could be a usefulwindow in this field, though complete characterization proved elusive.3

  20. Petrochemical types of kimberlites and their diamond-bearing capacity

    Science.gov (United States)

    Kostrovitsky, Sergey

    2010-05-01

    Kimberlite rocks of Yakutian province (belong to 1 group of kimberlites after Smith, 1983) are characterized by wide variations of rock-forming oxides [Ilupin et al., 1986; Milashev, 1965; Kharkiv et al., 1991]. A number of factors could be discussed to explain the variety of chemical compositions of rocks. The first factor, explaining the regional differences in the kimberlite composition with primarily different composition of source kimberlite melt-fluid, is conventionally called «primary». All other factors are connected with the secondary redistribution of chemical components of kimberlites. Irrespective of intensity of secondary factors, the primary composition of kimberlites varies broadly, which is noticeable in kimberlites of some provinces, kimberlites fields, pipe clusters and individual pipes. The petrochemical types are classified based on the contents of such oxides as FeO, TiO2 and K2O, being relatively inert in the secondary processes. In the Yakutian Province we have distinguished 5 petrochemical types of kimberlites (Kostrovitsky et al, 2007); with principal ones - high-Mg, magnesium-ferruginous (Mg-Fe) and ferruginous-titaniferous, their composition: diamond-bearing capacity of kimberlites were identified some time before. The essence of petrochemical criterion consists of the inverse correlation dependence between the contents FeOtotal, TiO2 in kimberlite rocks and their diamond-bearing capacity (Milashev, 1965; Krivonos, 1998). The mineralogical criteria of diamond-bearing capacity infer presence of direct dependence of the rate of capacity on the content in kimberlites of low-Ca, high-Cr garnet and chrome spinellids with Cr2O3 > 62% and TiO2 diamond-bearing capacity exemplified by the deposits of Yakutian Province. The high-Mg kimberlites of the Njurba, Botuoba, International and Aikhal pipes are known as mostly diamondiferous. Kimberlites of these fields are marked by absence or minor abundance of minerals of low-Cr megacryst association