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Sample records for ce igcc repowering

  1. IGCC demonstration project status combustion engineering IGCC repowering project

    International Nuclear Information System (INIS)

    Glamuzina, R.W.; Allen, R.J.; Peletz, L.J.

    1993-01-01

    This demonstration project was originally conceived as the repowering of an existing plant facility, the Lakeside Station in Springfield, Illinois. The Owner, City Water, Light and Power (CWL ampersand P), has removed five of the original boilers and three of the original turbines. The buildings have had asbestos insulation removed and the interiors have been prepared for the construction of a single Integrated Gasification Combined Cycle (IGCC) process train that will generate a net output of 60 megawatts. The plant consists of a combined cycle (gas turbine, heat recovery steam generator, steam turbine) power train located in the existing buildings and a coal gasification system in a new building. The gasification system contains ABB CE's air-blown, entrained flow, two stage gasifier, an advanced hot gas desulfurization system by General Electric Environmental Services, Inc. and the necessary auxiliary systems. The plant is designed to produce a nominal 60 MW net output with an ambient air temperature of 95 degrees F and a cooling water temperature of 89 degrees F on either Natural Gas or Illinois No. 5 coal

  2. Biomass IGCC

    Energy Technology Data Exchange (ETDEWEB)

    Salo, K; Keraenen, H [Enviropower Inc., Espoo (Finland)

    1997-12-31

    Enviropower Inc. is developing a modern power plant concept based on pressurised fluidized-bed gasification and gas turbine combined cycle (IGCC). The process is capable of maximising the electricity production with a variety of solid fuels - different biomass and coal types - mixed or separately. The development work is conducted on many levels. These and demonstration efforts are highlighted in this article. The feasibility of a pressurised gasification based processes compared to competing technologies in different applications is discussed. The potential of power production from biomass is also reviewed. (orig.) 4 refs.

  3. Biomass IGCC

    Energy Technology Data Exchange (ETDEWEB)

    Salo, K.; Keraenen, H. [Enviropower Inc., Espoo (Finland)

    1996-12-31

    Enviropower Inc. is developing a modern power plant concept based on pressurised fluidized-bed gasification and gas turbine combined cycle (IGCC). The process is capable of maximising the electricity production with a variety of solid fuels - different biomass and coal types - mixed or separately. The development work is conducted on many levels. These and demonstration efforts are highlighted in this article. The feasibility of a pressurised gasification based processes compared to competing technologies in different applications is discussed. The potential of power production from biomass is also reviewed. (orig.) 4 refs.

  4. Commercialization of IGCC technology looks promising

    International Nuclear Information System (INIS)

    Smith, D.J.

    1992-01-01

    This paper reports that a major focus of the latest round of the U.S. Department of Energy's Clean Coal Technology Program was three large-scale, high-efficiency electricity generating projects which will rely on coal gasification rather than burning the coal directly. The three projects are: Toms Creek integrated gasification combined-cycle (IGCC) demonstration project. The aim of the project is to demonstrate improved coal-to-power efficiencies in an integrated gasification combined-cycle process. According to the DOE, the Toms Creek project will show that significant reductions in SO 2 and NO x emissions can be accomplished through the use of IGCC technology. On completion of the project, 107 MW of electric capacity will be added to the grid. Pinon Pine IGCC power project. The project's aim is to demonstrate that IGCC plants can be constructed at significantly lower capital costs, and with higher thermal efficiencies, than conventional power generation technologies. It will also demonstrate the effectiveness of hot gas cleanup for low-sulfur western coals. Wasbash River coal gasification repowering project

  5. Technical and economic assessments commercial success for IGCC technology in China

    International Nuclear Information System (INIS)

    Xiong, T.

    1998-01-01

    The experiences gained from several Integrated Gasification Combined Cycle (IGCC) demonstration plants operating in the US and Europe facilitate commercial success of this advanced coal-based power generation technology. However, commercialization of coal-based IGCC technology in the West, particularly in the US, is restricted due to the low price of natural gas. On the contrary, in China--the largest coal producer and consumer in the world--a lack of natural gas supply, strong demand for air pollution control and relatively low costs of manufacturing and construction provide tremendous opportunities for IGCC applications. The first Chinese IGCC demonstration project was initiated in 1994, and other potential IGCC projects are in planning. IGCC applications in re-powering, fuel switching and multi-generation also show a great market potential in China. However, questions for IGCC development in China remain; where are realistic opportunities for IGCC projects and how can these opportunities be converted into commercial success? The answers to these questions should focus on the Chinese market needs and emphasize economic benefits, not just clean, or power. High price of imported equipment, high financing costs, and the technical risk of first-of-a-kind installation barricade IGCC development in China. This paper presents preliminary technical and economic assessments for four typical IGCC applications in the Chinese marketplace: central power station, fuel switching, re-powering, and multi-generation. The major factors affecting project economics--such as plant cost, financing, prices of fuel and electricity and operating capacity factor--are analyzed. The results indicate that well-proven technology for versatile applications, preferred financing, reduction of the plant cost, environmental superiority and appropriate project structure are the key for commercial success of IGCC in China

  6. Wabash River Coal Gasification Repowering Project: A DOE Assessment; FINAL

    International Nuclear Information System (INIS)

    National Energy Technology Laboratory

    2002-01-01

    The goal of the U.S. Department of Energy (DOE) Clean Coal Technology Program (CCT) is to furnish the energy marketplace with a number of advanced, more efficient, and environmentally responsible coal utilization technologies through demonstration projects. These projects seek to establish the commercial feasibility of the most promising advanced coal technologies that have developed beyond the proof-of-concept stage. This document serves as a DOE post-project assessment (PPA) of a project selected in CCT Round IV, the Wabash River Coal Gasification Repowering (WRCGR) Project, as described in a Report to Congress (U.S. Department of Energy 1992). Repowering consists of replacing an existing coal-fired boiler with one or more clean coal technologies to achieve significantly improved environmental performance. The desire to demonstrate utility repowering with a two-stage, pressurized, oxygen-blown, entrained-flow, integrated gasification combined-cycle (IGCC) system prompted Destec Energy, Inc., and PSI Energy, Inc., to form a joint venture and submit a proposal for this project. In July 1992, the Wabash River Coal Gasification Repowering Project Joint Venture (WRCGRPJV, the Participant) entered into a cooperative agreement with DOE to conduct this project. The project was sited at PSI Energy's Wabash River Generating Station, located in West Terre Haute, Indiana. The purpose of this CCT project was to demonstrate IGCC repowering using a Destec gasifier and to assess long-term reliability, availability, and maintainability of the system at a fully commercial scale. DOE provided 50 percent of the total project funding (for capital and operating costs during the demonstration period) of$438 million

  7. Repowering with natural gas

    International Nuclear Information System (INIS)

    Wilkinson, P.L.

    1992-01-01

    This chapter examines the concept of combined-cycle repowering with natural gas as one possible solution to the impending dilemma facing electric utilities - tight capacity margins in the 1990s and the inordinate expense of traditional powerplants. Combined-cycle repowering refers to the production of electricity through the integration of new and used equipment at an existing site, with the final equipment configuration resembling a new gas-fired combined-cycle unit (i.e., gas turbine, waste heat recovery unit and steam turbine/generator). Through the utilization of improved waste heat recovery and gas-fired equipment, repowering provides both additional capacity and increased generating efficiency. Three modes of repowering are considered: (1) peak turbine repowering refers to the addition of a steam turbine and heat recovery unit to an existing gas turbine, with the efficiency improvement allowing the unit to convert from peaking to baseload operation; (2) heat recovery repowering is the replacement of an old coal boiler with a gas turbine and heat recovery unit, leaving the existing steam turbine in place; and (3) boiler repowering, in which the exhaust from a new gas turbine is fed into an existing coal boiler, replacing existing forced-draft fans and air heaters. These three options are compared with the option of adding new coal-fired boilers on the basis of economics, energy efficiency and environmental impacts

  8. WABASH RIVER COAL GASIFICATION REPOWERING PROJECT

    Energy Technology Data Exchange (ETDEWEB)

    Unknown

    2000-09-01

    The close of 1999 marked the completion of the Demonstration Period of the Wabash River Coal Gasification Repowering Project. This Final Report summarizes the engineering and construction phases and details the learning experiences from the first four years of commercial operation that made up the Demonstration Period under Department of Energy (DOE) Cooperative Agreement DE-FC21-92MC29310. This 262 MWe project is a joint venture of Global Energy Inc. (Global acquired Destec Energy's gasification assets from Dynegy in 1999) and PSI Energy, a part of Cinergy Corp. The Joint Venture was formed to participate in the Department of Energy's Clean Coal Technology (CCT) program and to demonstrate coal gasification repowering of an existing generating unit impacted by the Clean Air Act Amendments. The participants jointly developed, separately designed, constructed, own, and are now operating an integrated coal gasification combined-cycle power plant, using Global Energy's E-Gas{trademark} technology (E-Gas{trademark} is the name given to the former Destec technology developed by Dow, Destec, and Dynegy). The E-Gas{trademark} process is integrated with a new General Electric 7FA combustion turbine generator and a heat recovery steam generator in the repowering of a 1950's-vintage Westinghouse steam turbine generator using some pre-existing coal handling facilities, interconnections, and other auxiliaries. The gasification facility utilizes local high sulfur coals (up to 5.9% sulfur) and produces synthetic gas (syngas), sulfur and slag by-products. The Project has the distinction of being the largest single train coal gasification combined-cycle plant in the Western Hemisphere and is the cleanest coal-fired plant of any type in the world. The Project was the first of the CCT integrated gasification combined-cycle (IGCC) projects to achieve commercial operation.

  9. Wabash River Coal Gasification Repowering Project: A DOE Assessment; FINAL

    International Nuclear Information System (INIS)

    National Energy Technology Laboratory

    2002-01-01

    The goal of the U.S. Department of Energy (DOE) Clean Coal Technology Program (CCT) is to furnish the energy marketplace with a number of advanced, more efficient, and environmentally responsible coal utilization technologies through demonstration projects. These projects seek to establish the commercial feasibility of the most promising advanced coal technologies that have developed beyond the proof-of-concept stage. This document serves as a DOE post-project assessment (PPA) of a project selected in CCT Round IV, the Wabash River Coal Gasification Repowering (WRCGR) Project, as described in a Report to Congress (U.S. Department of Energy 1992). Repowering consists of replacing an existing coal-fired boiler with one or more clean coal technologies to achieve significantly improved environmental performance. The desire to demonstrate utility repowering with a two-stage, pressurized, oxygen-blown, entrained-flow, integrated gasification combined-cycle (IGCC) system prompted Destec Energy, Inc., and PSI Energy, Inc., to form a joint venture and submit a proposal for this project. In July 1992, the Wabash River Coal Gasification Repowering Project Joint Venture (WRCGRPJV, the Participant) entered into a cooperative agreement with DOE to conduct this project. The project was sited at PSI Energy's Wabash River Generating Station, located in West Terre Haute, Indiana. The purpose of this CCT project was to demonstrate IGCC repowering using a Destec gasifier and to assess long-term reliability, availability, and maintainability of the system at a fully commercial scale. DOE provided 50 percent of the total project funding (for capital and operating costs during the demonstration period) of$438 million. Construction for the demonstration project was started in July 1993. Pre-operational tests were initiated in August 1995, and construction was completed in November 1995. Commercial operation began in November 1995, and the demonstration period was completed in December

  10. IGCC technology and demonstration

    Energy Technology Data Exchange (ETDEWEB)

    Palonen, J [A. Ahlstrom Corporation, Karhula (Finland). Hans Ahlstrom Lab.; Lundqvist, R G [A. Ahlstrom Corporation, Helsinki (Finland); Staahl, K [Sydkraft AB, Malmoe (Sweden)

    1997-12-31

    Future energy production will be performed by advanced technologies that are more efficient, more environmentally friendly and less expensive than current technologies. Integrated gasification combined cycle (IGCC) power plants have been proposed as one of these systems. Utilising biofuels in future energy production will also be emphasised since this lowers substantially carbon dioxide emissions into the atmosphere due to the fact that biomass is a renewable form of energy. Combining advanced technology and biomass utilisation is for this reason something that should and will be encouraged. A. Ahlstrom Corporation of Finland and Sydkraft AB of Sweden have as one part of company strategies adopted this approach for the future. The companies have joined their resources in developing a biomass-based IGCC system with the gasification part based on pressurised circulating fluidized-bed technology. With this kind of technology electrical efficiency can be substantially increased compared to conventional power plants. As a first concrete step, a decision has been made to build a demonstration plant. This plant, located in Vaernamo, Sweden, has already been built and is now in commissioning and demonstration stage. The system comprises a fuel drying plant, a pressurised CFB gasifier with gas cooling and cleaning, a gas turbine, a waste heat recovery unit and a steam turbine. The plant is the first in the world where the integration of a pressurised gasifier with a gas turbine will be realised utilising a low calorific gas produced from biomass. The capacity of the Vaernamo plant is 6 MW of electricity and 9 MW of district heating. Technology development is in progress for design of plants of sizes from 20 to 120 MWe. The paper describes the Bioflow IGCC system, the Vaernamo demonstration plant and experiences from the commissioning and demonstration stages. (orig.)

  11. IGCC technology and demonstration

    Energy Technology Data Exchange (ETDEWEB)

    Palonen, J. [A. Ahlstrom Corporation, Karhula (Finland). Hans Ahlstrom Lab.; Lundqvist, R.G. [A. Ahlstrom Corporation, Helsinki (Finland); Staahl, K. [Sydkraft AB, Malmoe (Sweden)

    1996-12-31

    Future energy production will be performed by advanced technologies that are more efficient, more environmentally friendly and less expensive than current technologies. Integrated gasification combined cycle (IGCC) power plants have been proposed as one of these systems. Utilising biofuels in future energy production will also be emphasised since this lowers substantially carbon dioxide emissions into the atmosphere due to the fact that biomass is a renewable form of energy. Combining advanced technology and biomass utilisation is for this reason something that should and will be encouraged. A. Ahlstrom Corporation of Finland and Sydkraft AB of Sweden have as one part of company strategies adopted this approach for the future. The companies have joined their resources in developing a biomass-based IGCC system with the gasification part based on pressurised circulating fluidized-bed technology. With this kind of technology electrical efficiency can be substantially increased compared to conventional power plants. As a first concrete step, a decision has been made to build a demonstration plant. This plant, located in Vaernamo, Sweden, has already been built and is now in commissioning and demonstration stage. The system comprises a fuel drying plant, a pressurised CFB gasifier with gas cooling and cleaning, a gas turbine, a waste heat recovery unit and a steam turbine. The plant is the first in the world where the integration of a pressurised gasifier with a gas turbine will be realised utilising a low calorific gas produced from biomass. The capacity of the Vaernamo plant is 6 MW of electricity and 9 MW of district heating. Technology development is in progress for design of plants of sizes from 20 to 120 MWe. The paper describes the Bioflow IGCC system, the Vaernamo demonstration plant and experiences from the commissioning and demonstration stages. (orig.)

  12. IGCC crosses the threshold

    Energy Technology Data Exchange (ETDEWEB)

    Broderick, J E

    1986-07-01

    This paper describes the development of the Texaco Coal Gasification Process (TCGP), the first of the advanced gasification processes to become commercialized. The utilization of this process in various demonstration and commercial plants is described. The design of the Cool Water integrated gasification combined cycle (IGCC) plant in California is discussed in some detail. This plant has been operating successfully since June 1984, and has demonstrated that the Texaco gasification technology for electric power generation is commercially viable, can use many different feedstocks, has substantial efficiency growth potential, can provide competitively lower cost electric power, and offers vastly superior environmental performance.

  13. Air permitting of IGCC plants

    Energy Technology Data Exchange (ETDEWEB)

    Chitikela, S.R.

    2007-07-01

    The IGCC process is, currently, the preferred choice over conventional thermal power production in regard to cleanup of fuel and significantly reduced contaminant emissions. The air permitting requirements include the review of: feed preparation and PM emissions; feed gasification and contaminant emissions; elemental sulfur recovery and SO{sub 2} emissions; options for carbon-dioxide recovery; syngas characteristics for combustion; CT design and combustion mechanisms; air contaminant emissions of CT; controlled CT emissions of nitrogen-oxides and carbon-monoxide gases using the SCR and oxidation catalysts, respectively; and, emission of volatile organic compounds (VOCs), and hazardous air pollutants (HAPs). However, the IGCC processes are being rigorously reviewed for the system integration and reliability, and significant reduction of air contaminant emissions (including the greenhouse gases). This paper included a review of IGCC air contaminant emission rates, and various applicable regulatory requirements, such as NSR (New Source Review), NSPS (New Source Performance Standards), and MACT (Maximum Achievable Control Technology). The IGCC facility's NOX, CO, SO{sub 2}, PM, VOCs, and HAPs emission rates would be significantly low. Thus, effective, construction and installation, and operation air permits would be necessary for IGCC facilities.

  14. Repowering options for steam power plants

    International Nuclear Information System (INIS)

    Wen, H.; Gopalarathinam, R.

    1992-01-01

    Repowering an existing steam power plant with a gas turbine offers an attractive alternative to a new plant or life extension, especially for unit sizes smaller than 300 MWe. Gas turbine repowering improves thermal efficiency and substantially increases the plant output. Based on recent repowering studies and projects, this paper examines gas turbine repowering options for 100 MWe, 200 MWe and 300 MWe units originally designed for coal firing and currently firing either coal or natural gas. Also discussed is the option for a phased future conversion of the repowered unit to fire coal-derived gas, should there be a fluctuation in the price or availability of natural gas. A modular coal gasification plant designed to shorten the conversion time is presented. Repowering options, performance, costs, and availability impacts are discussed for selected cases

  15. Solar thermal repowering systems integration. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Dubberly, L. J.; Gormely, J. E.; McKenzie, A. W.

    1979-08-01

    This report is a solar repowering integration analysis which defines the balance-of-plant characteristics and costs associated with the solar thermal repowering of existing gas/oil-fired electric generating plants. Solar repowering interface requirements for water/steam and salt or sodium-cooled central receivers are defined for unit sizes ranging from 50 MWe non-reheat to 350 MWe reheat. Finally balance-of-plant cost estimates are presented for each of six combinations of plant type, receiver type and percent solar repowering.

  16. Offshore wind farm repowering optimization

    DEFF Research Database (Denmark)

    Hou, Peng; Enevoldsen, Peter; Hu, Weihao

    2017-01-01

    is focused on optimization of offshore wind farm repowering, which is one option for the wind farm owner at end of life for the offshore wind farm. The LCoE is used as the evaluation index to identify whether it is economical to invest in such a way. In an optimized repowering strategy, different types...... of wind turbines are selected to replace the original wind turbines to reconstruct the wind farm, which is demonstrated to be better than the refurbishment approach which replaces the old wind turbines with the same type. The simulations performed in this research reveal that the reconstructed wind farm......, which consists of multiple types of wind turbine, has a smaller LCoE (10.43%) than the refurbishment approach, which shows the superiority of the proposed method. This research contributes an optimization tool to the wind industry, which consequently drives down the cost of energy produced by offshore...

  17. Sulphur removal in IGCC projects

    Energy Technology Data Exchange (ETDEWEB)

    Cross, F. (Parsons (United Kingdom))

    1998-01-01

    The technology for recovering elemental sulphur from H[sub 2]S bearing gases is well established. The modified Claus Process is the principal work-horse in sulphur recovery and can customarily achieve conversion efficiencies of 95% or better. Nowadays, such a level of recovery is no longer sufficient in most instances and sulphur recovery facility must then include some form of enhanced recovery, usually by treating the Claus tail gas. A number of processes have been introduced to enable the overall recovery to be increased. Recoveries in excess of 99% are both feasible and economic. Use of oxygen in place has become very popular in cases where oxygen is available cheaply or where capacity increases are designed. Most IGCC projects needing an air separation plant would automatically benefit from extending the use of oxygen to the sulphur recovery plant. The most popular route to minimising sulphur emissions in the context of IGCC projects has involved an oxygen based Claus plant followed by tail gas hydrogenation, hydrogen sulphide recovery and its recycle to the Claus section. The recovery of H[sub 2]S from the Claus tail gas can be integrated with the main gas treating system in the gasification plant. The cost advantage of doing so is significant. Parsons has been involved with the technology since 1949 and has been responsible for developments such as the ammonia burning Claus and jointly with Unocal, the BSRP tail gas process and Selectox processes. Recent innovations in response changing environmental and production requirements have included catalytic and tail gas processes which reduce sulphur emissions. 6 figs., 2 tabs.

  18. Sulphur removal in IGCC projects

    Energy Technology Data Exchange (ETDEWEB)

    Cross, F. [Parsons (United Kingdom)

    1998-12-31

    The technology for recovering elemental sulphur from H{sub 2}S bearing gases is well established. The modified Claus Process is the principal work-horse in sulphur recovery and can customarily achieve conversion efficiencies of 95% or better. Nowadays, such a level of recovery is no longer sufficient in most instances and sulphur recovery facility must then include some form of enhanced recovery, usually by treating the Claus tail gas. A number of processes have been introduced to enable the overall recovery to be increased. Recoveries in excess of 99% are both feasible and economic. Use of oxygen in place has become very popular in cases where oxygen is available cheaply or where capacity increases are designed. Most IGCC projects needing an air separation plant would automatically benefit from extending the use of oxygen to the sulphur recovery plant. The most popular route to minimising sulphur emissions in the context of IGCC projects has involved an oxygen based Claus plant followed by tail gas hydrogenation, hydrogen sulphide recovery and its recycle to the Claus section. The recovery of H{sub 2}S from the Claus tail gas can be integrated with the main gas treating system in the gasification plant. The cost advantage of doing so is significant. Parsons has been involved with the technology since 1949 and has been responsible for developments such as the ammonia burning Claus and jointly with Unocal, the BSRP tail gas process and Selectox processes. Recent innovations in response changing environmental and production requirements have included catalytic and tail gas processes which reduce sulphur emissions. 6 figs., 2 tabs.

  19. EPA RE-Powering Screening Shapefile

    Data.gov (United States)

    U.S. Environmental Protection Agency — The U.S. Environmental Protection Agency (EPA) Office of Land and Emergency Management (OLEM) Center for Program Analysis (CPA) initiated the RE-Powering America’s...

  20. Pinon Pine IGCC project status

    International Nuclear Information System (INIS)

    Higginbotham, E.B.; Lamarre, L.J.; Glazer, M.

    1993-01-01

    Sierra Pacific Power Company (SPPCo) intends to build the Pinon Pine Power Project, an integrated coal gasification combined cycle (IGCC) plant at its Tracy Power Station near Reno, Nevada. The plant will burn approximately 800 tons of coal per day to generate electricity in a base load application. The Pinon Project was selected by the U.S. Department of Energy (DOE) for funding under Round IV of the Clean Coal Technology Program. The project will demonstrate the use of the KRW agglomerating fluidized bed gasifer operating in the air blown mode. Hot gas cleanup consisting of particulate and sulfur removal will also be demonstrated. The Cooperative Agreement between SPPCo and the DOE was executed in August 1992. Foster Wheeler USA Corporation (FWUSA) will provide engineering and construction management services. The M.W. Kellogg Company (MWK) will provide engineering of the gasifer and hot gas cleanup systems. A discussion of project progress since the 1992 Clean Coal Technology Conference, design and economic considerations, and current project status is presented

  1. Wind Power Project Repowering: History, Economics, and Demand (Presentation)

    Energy Technology Data Exchange (ETDEWEB)

    Lantz, E.

    2015-01-01

    This presentation summarizes a related NREL technical report and seeks to capture the current status of wind power project repowering in the U.S. and globally, analyze the economic and financial decision drivers that surround repowering, and to quantify the level and timing of demand for new turbine equipment to supply the repowering market.

  2. Repowering of wind farms - A case study

    Energy Technology Data Exchange (ETDEWEB)

    Nivedh, B.S. [Quality Engineering and Software Technologies, Bangalore (India); Devi, R.P.K. [College of Engineering. Power Systems Engineering, Guindy (India); Sreevalsan, E. [Gamesa Wind Turbines India Private Limited, Chennai (India)

    2012-07-01

    The main objective of the study is to devise a method for assessing the repowering potential and to improve the energy output from the wind farms and also to understand the impact on the power quality due to repowering. With repowering, the first-generation wind turbines can be replaced with modern multi-megawatt wind turbines. To carry-out the study an old wind farm located at Kayathar, Tamilnadu is selected. The wind farm was commissioned in 1990's with a capacity of 7.35MW, which consists of 36 Wind Turbines each with the capacity of 200kW and 225kW. The present annual energy generation of the wind farm is 7350MWhr with the plant load factor of 11.41%. The intent of this study is to predict the annual energy output of the wind farm after the repowering using WAsP (Wind Atlas Analysis Application Program). Further this study analyses the power quality issues of the various Wind Turbines. In addition, the main feeder, in which the wind farm which is taken for the study also modeled and the impact on power quality due to repowering also studied. Simulations were carried out using MATLAB. The results are analyzed to understand the significance of repowering to overcome the energy crisis of the nation since the best locations for wind in India are occupied by old wind turbines. The following are the observations and conclusions from the above study. Plant load factor (PLF) increased to 24 %, Energy yield increased to more than 4 times and the capacity of the wind farm became double. And in the view of power quality, comparing to the existing Feeder, Repowered Feeder having less reactive power consumption, voltage variations and flickers except the harmonic distortion. (Author)

  3. Strategic thinking on IGCC development in China

    International Nuclear Information System (INIS)

    Liu Hengwei; Ni Weidou; Li Zheng; Ma Linwei

    2008-01-01

    With electricity demand growing at a torrid pace-about 15% per year, faster than any other country in the world-China is fast-tracking the construction of new generation facilities, about 80% of which are coal-fired. China's total capacity in the reference scenario of World Energy Outlook 2006 (WEO2006) released by the International Energy Agency (IEA) is projected to practically 3.4 times, from 442 GW in 2004 to 1496 GW in 2030, growing at 4.8% per year on average. The vast majority of this huge generation requirement will still be met through the construction of coal power plants. Because new coal power plants built today have a long life cycle and are not easy to upgrade the technologies involved, decisions made now will have a major impact on the coal utilization mode in the coming years. Thus, the future 20 years is the strategic opportunity period of the transition of conventional coal utilization. Because the Integrated Gasification Combined Cycle (IGCC) can supply electricity, liquid fuels, hydrogen and other chemicals if needed at low pollution level, and has the potential to make carbon capture and sequestration much easier and cheaper than traditional pulverized coal boiler power plants, it should be the strategic direction for China to meet the requirements of the energy and environmental challenges. This paper makes an overview of China's energy and environmental challenges and opportunities, and describes the IGCC technology. It discusses why China should develop IGCC. What are the foundations for China to develop IGCC? What are the rational driving forces to develop IGCC in China? What is the reasonable developing path of IGCC in China?

  4. Advanced IGCC/Hydrogen Gas Turbine Development

    Energy Technology Data Exchange (ETDEWEB)

    York, William [General Electric Company, Schenectady, NY (United States); Hughes, Michael [General Electric Company, Schenectady, NY (United States); Berry, Jonathan [General Electric Company, Schenectady, NY (United States); Russell, Tamara [General Electric Company, Schenectady, NY (United States); Lau, Y. C. [General Electric Company, Schenectady, NY (United States); Liu, Shan [General Electric Company, Schenectady, NY (United States); Arnett, Michael [General Electric Company, Schenectady, NY (United States); Peck, Arthur [General Electric Company, Schenectady, NY (United States); Tralshawala, Nilesh [General Electric Company, Schenectady, NY (United States); Weber, Joseph [General Electric Company, Schenectady, NY (United States); Benjamin, Marc [General Electric Company, Schenectady, NY (United States); Iduate, Michelle [General Electric Company, Schenectady, NY (United States); Kittleson, Jacob [General Electric Company, Schenectady, NY (United States); Garcia-Crespo, Andres [General Electric Company, Schenectady, NY (United States); Delvaux, John [General Electric Company, Schenectady, NY (United States); Casanova, Fernando [General Electric Company, Schenectady, NY (United States); Lacy, Ben [General Electric Company, Schenectady, NY (United States); Brzek, Brian [General Electric Company, Schenectady, NY (United States); Wolfe, Chris [General Electric Company, Schenectady, NY (United States); Palafox, Pepe [General Electric Company, Schenectady, NY (United States); Ding, Ben [General Electric Company, Schenectady, NY (United States); Badding, Bruce [General Electric Company, Schenectady, NY (United States); McDuffie, Dwayne [General Electric Company, Schenectady, NY (United States); Zemsky, Christine [General Electric Company, Schenectady, NY (United States)

    2015-07-30

    The objective of this program was to develop the technologies required for a fuel flexible (coal derived hydrogen or syngas) gas turbine for IGCC that met DOE turbine performance goals. The overall DOE Advanced Power System goal was to conduct the research and development (R&D) necessary to produce coal-based IGCC power systems with high efficiency, near-zero emissions, and competitive capital cost. To meet this goal, the DOE Fossil Energy Turbine Program had as an interim objective of 2 to 3 percentage points improvement in combined cycle (CC) efficiency. The final goal is 3 to 5 percentage points improvement in CC efficiency above the state of the art for CC turbines in IGCC applications at the time the program started. The efficiency goals were for NOx emissions of less than 2 ppm NOx (@15 % O2). As a result of the technologies developed under this program, the DOE goals were exceeded with a projected 8 point efficiency improvement. In addition, a new combustion technology was conceived of and developed to overcome the challenges of burning hydrogen and achieving the DOE’s NOx goal. This report also covers the developments under the ARRA-funded portion of the program that include gas turbine technology advancements for improvement in the efficiency, emissions, and cost performance of gas turbines for industrial applications with carbon capture and sequestration. Example applications could be cement plants, chemical plants, refineries, steel and aluminum plants, manufacturing facilities, etc. The DOE’s goal for more than 5 percentage point improvement in efficiency was met with cycle analyses performed for representative IGCC Steel Mill and IGCC Refinery applications. Technologies were developed in this program under the following areas: combustion, larger latter stage buckets, CMC and EBC, advanced materials and coatings, advanced configurations to reduce cooling, sealing and rotor purge flows, turbine aerodynamics, advanced sensors, advancements in first

  5. Commercial gasifier for IGCC applications study report

    Energy Technology Data Exchange (ETDEWEB)

    Notestein, J.E.

    1990-06-01

    This was a scoping-level study to identify and characterize the design features of fixed-bed gasifiers appearing most important for a gasifier that was to be (1) potentially commercially attractive, and (2) specifically intended for us in integrated coal gasification/combined-cycle (IGCC) applications. It also performed comparative analyses on the impact or value of these design features and on performance characteristics options of the whole IGCC system since cost, efficiency, environmental traits, and operability -- on a system basis -- are what is really important. The study also reviewed and evaluated existing gasifier designs, produced a conceptual-level gasifier design, and generated a moderately advanced system configuration that was utilized as the reference framework for the comparative analyses. In addition, technical issues and knowledge gaps were defined. 70 figs., 31 tabs.

  6. Thermal and sintering characterization of IGCC slag

    Energy Technology Data Exchange (ETDEWEB)

    Acosta, A.; Iglesias, I.; Aineto, M.; Romero, M.; Rincon, J.M. [University of Castilla La Mancha, Ciudad Real (Spain)

    2002-07-01

    IGCC slag is a vitreous residual product from the new induction gasification combined cycle gasification thermal power plants. In order to characterize this waste as secondary raw material for the production of glasses and glass-ceramics as construction materials, slag from the Puertollano, Ciudad Real, Spain power plants was thermally investigated. After controlled heating this waste gives rise to hematite, anorthite, and cristobalite crystallized materials.

  7. Heat integration and analysis of decarbonised IGCC sites

    Energy Technology Data Exchange (ETDEWEB)

    Ng, K.S.; Lopez, Y.; Campbell, G.M.; Sadhukhan, J. [University of Manchester, Manchester (United Kingdom). School of Chemical Engineering & Analytical Science

    2010-02-15

    Integrated gasification combined cycle (IGCC) power generation systems have become of interest due to their high combined heat and power (CHP) generation efficiency and flexibility to include carbon capture and storage (CCS) in order to reduce CO{sub 2} emissions. However, IGCC's biggest challenge is its high cost of energy production. In this study, decarbonised coal IGCC sites integrated with CCS have been investigated for heat integration and economic value analyses. It is envisaged that the high energy production cost of an IGCC site can be offset by maximising site-wide heat recovery and thereby improving the cost of electricity (COE) of CHP generation. Strategies for designing high efficiency CHP networks have been proposed based on thermodynamic heuristics and pinch theory. Additionally, a comprehensive methodology to determine the COE from a process site has been developed. In this work, we have established thermodynamic and economic comparisons between IGCC sites with and without CCS and a trade-off between the degree of decarbonisation and the COE from the heat integrated IGCC sites. The results show that the COE from the heat integrated decarbonised IGCC sites is significantly lower compared to IGCC sites without heat integration making application of CCS in IGCC sites economically competitive.

  8. Api Energia IGCC plant is fully integrated with refinery

    Energy Technology Data Exchange (ETDEWEB)

    Del Bravo, R. [api Energia, Rome (Italy); Trifilo, R. [ABB Sadelmi, Milan (Italy); Chiantore, P.V. [api anonima petroli Italiania Spa, Rome (Italy); Starace, F. [ABB Power Generation, Baden (Switzerland); O`Keefe, L.F. [Texico, White Plains (United States)

    1998-06-01

    The api Energia integrated gasification combined cycle (IGCC) plant being built at Falconara Marittima, on Italy`s Adriatic coast, is one of the three IGCC plants under construction in Italy following the liberalization of the electricity production sector. The plant will take 59.2 t/h of high sulphur heavy oil produced by the Falconara refinery, convert it to syngas and use the gas to generate 280 MW of electricity, plus steam and other gases for use in the refinery. The IGCC plant will be highly integrated into the refining process, with a large number of interchanges between the IGCC unit and the rest of the refinery. (author)

  9. Repowering - Next big thing in India

    International Nuclear Information System (INIS)

    Goyal, Mohit

    2010-01-01

    Indian wind energy sector has seen a CAGR of more than 27% during the period 2002-2007. However, the annual capacity additions has been declining for the past 2 years and recently, India lost one place in the Global ranking on total installed wind capacity to China. While issues like unfavourable tariff, non-uniform state policies, unavailability of evacuation infrastructure, etc. can be attributed to the slower pace of capacity addition, the issue of unavailability of on-shore wind sites with sufficiently high wind velocity is expected to take centre stage in the next 2-3 years. Wind sites with low wind velocity make the investment unattractive to developers. Given the current situation, repowering as an investment option, which has already seen favourable response in countries like Germany and Denmark, would start maturing in India. This paper analyzes the present situation of the wind energy in India, evaluates the different wind energy market segments including repowering market, provides financial highlights of the repowering concept and ends with concluding remarks on major triggers which can set this concept in motion. (author)

  10. MHD repowering of a 250 MWe unit of the TVA Allen Steam Plant

    International Nuclear Information System (INIS)

    Chapman, J.N.; Attig, R.C.

    1992-01-01

    In this paper coal fired MHD repowering is considered for the TVA Allen Steam Plant. The performance of the repowered plant is presented. Cost comparisons are made of the cost of repowering with MHD versus the cost of meeting similar standards by installing scrubbers and selective catalytic NO x reduction (SCNR). For repowering of a single 250 MW e unit, the costs favor scrubbing and SCNR. If one considers a single repowering of all three 250 MW e units by a single MHD topping cycle and boiler, MHD repowering is more economical. Environmental emissions from the repowered plant are estimated

  11. Technical and economic assessment of solar hybrid repowering. Final report

    Energy Technology Data Exchange (ETDEWEB)

    None

    1978-09-01

    Drawings are presented for the repowering project described in SAN--1608-4-1. Reeves Sation No. 2 was selected for study for repowering at 50 percent (25 MWe) using the 10-MW solar central receiver pilot plant preliminary design for Barstow, California. (WHK)

  12. Dynamic modeling of IGCC power plants

    International Nuclear Information System (INIS)

    Casella, F.; Colonna, P.

    2012-01-01

    Integrated Gasification Combined Cycle (IGCC) power plants are an effective option to reduce emissions and implement carbon-dioxide sequestration. The combination of a very complex fuel-processing plant and a combined cycle power station leads to challenging problems as far as dynamic operation is concerned. Dynamic performance is extremely relevant because recent developments in the electricity market push toward an ever more flexible and varying operation of power plants. A dynamic model of the entire system and models of its sub-systems are indispensable tools in order to perform computer simulations aimed at process and control design. This paper presents the development of the lumped-parameters dynamic model of an entrained-flow gasifier, with special emphasis on the modeling approach. The model is implemented into software by means of the Modelica language and validated by comparison with one set of data related to the steady operation of the gasifier of the Buggenum power station in the Netherlands. Furthermore, in order to demonstrate the potential of the proposed modeling approach and the use of simulation for control design purposes, a complete model of an exemplary IGCC power plant, including its control system, has been developed, by re-using existing models of combined cycle plant components; the results of a load dispatch ramp simulation are presented and shortly discussed. - Highlights: ► The acausal dynamic model of an entrained gasifier has been developed. ► The model can be used to perform system optimization and control studies. ► The model has been validated using field data. ► Model use is illustrated with an example showing the transient of an IGCC plant.

  13. Improved repowering techniques for power plants

    DEFF Research Database (Denmark)

    Houbak, Niels; Andersen, Simon E.; Petersen, Stiig Bo

    1998-01-01

    Repowering of existing coal-fired power plants is often accomplished by adding gas turbines. In this paper we assume that the gas turbine exhaust is used for feed water preheating.Typical gas turbine exhaust temperatures are in the range 450-600C whereas typical boiler inlet temperatures are 250......-300C. The big difference in temperature between exhaust and water prevents an efficient exchange of heat. One way to lower the exhaust temperature is to expand the gas to sub atmospheric pressure. The result is a 50% increase in possible installed gas turbine power....

  14. Air toxics emissions from an IGCC process

    Energy Technology Data Exchange (ETDEWEB)

    Mojtahedi, W.; Norrbacka, P. [Enviropower Inc., Espoo (Finland); Hinderson, A. [Vattenfall (Sweden); Rosenberg, R.; Zilliacus, R.; Kurkela, E.; Nieminen, M. [VTT Energy, Espoo (Finland); Hoffren, H. [IVO International Oy, Vantaa (Finland)

    1996-12-01

    The so-called simplified coal gasification combined cycle process, incorporating air gasification and hot gas cleanup, promises high power generation efficiency in an environmentally acceptable manner. Increasingly more stringent environmental regulations have focused attention on the emissions of not only SO{sub 2} and NO{sub x} but also on the so-called air toxics which include a number of toxic trace elements. As result of recent amendments to the United States Clean Air Act, IGCC emissions of eleven trace elements: antimony, arsenic, beryllium, cadmium, chromium, cobalt, lead, manganese, mercury, nickel, selenium - as well as the radionuclides uranium and thorium may be regulated. Similarly, air missions standards in Europe include a limit of 0.05 mg Nm{sup 3} for mercury and cadmium and 1.0 3/Nm{sup 3} for other class I trace elements. A suitable sampling/measuring system has been developed in this project (in cooperation with Imatran Voima Oy, Electric Power Research Institute (EPRI) and Radian Cooperation) which will be used in the pressurized gasification tests. This will enable an accurate measurement of the volatilized trace element species, at high temperature and pressure, which may be found in the vapour phase. Models are being developed that can be used to determine not only the chemical equilibrium composition of gaseous, liquid and solid phases, but also possible interactions of the gaseous species with aerosol particles and surfaces, These should be used to more accurately assess the impact of the toxic trace metals emitted from the simplified IGCC system

  15. Market potential of IGCC for domestic power production

    International Nuclear Information System (INIS)

    Gray, D.; Tomlinson, G.; Hawk, E.; Maskew, J.

    1999-01-01

    Mitretek Systems and CONSOL Inc. have completed the first phase of a market potential study for Integrated Coal Gasification Combined Cycle (IGCC) domestic power production. The U. S. Department of Energy (DOE) funded this study. The objective of this study is to provide DOE with data to estimate the future domestic market potential of IGCC for electricity generation. Major drivers in this study are the state of technology development, feedstock costs, environmental control costs, demand growth, and dispatchability. This study examines IGCC potential for baseload power production in the Northeast U. S., an important market area by virtue of existing coal infrastructure and proximity to coal producing regions. IGCC market potential was examined for two levels of technology development as a function of natural gas price and carbon tax. This paper discusses the results of this study, including the levels of performance and cost necessary to insure competitiveness with natural gas combined cycle plants

  16. Puertollano IGCC plant. Present position and future competitiveness

    Energy Technology Data Exchange (ETDEWEB)

    Pedro Casero; Francisco Garcia-Pena

    2006-07-01

    This paper discusses the current status of the Puertollano 350 MW IGCC demonstration power plant in Spain. The experience provided by the operation of this plant during the last years is described, focussing on the core systems of the plant (gasifier, gas cleaning and gas turbines). Bottlenecks and weak points related to these systems are identified, along with the improvements. The production of hydrogen from coal at an IGCC plant is also discussed. 9 figs., 2 tabs.

  17. Demonstration of IGCC features - plant integration and syngas combustion

    Energy Technology Data Exchange (ETDEWEB)

    Hannemann, F.; Huth, M.; Karg, J.; Schiffers, U. [Siemens AG Power Generation (KWU), Erlanger/Muelheim (Germany)

    2000-07-01

    Siemens is involved in three IGCC plants in Europe that are currently in operation. Against the background of the Puertollano and Buggenum plants, some of the specific new features of fully integrated IGCC power plants are discussed, including: requirements and design features of the gas turbine syngas supply system; gas turbine operating experience with air extraction for the air separation unit from the gas turbine air compressor; and design requirements and operational features of the combustion system. 7 refs., 17 figs., 1 tab.

  18. Wind Power Project Repowering: Financial Feasibility, Decision Drivers, and Supply Chain Effects

    Energy Technology Data Exchange (ETDEWEB)

    Lantz, Eric [National Renewable Energy Lab. (NREL), Golden, CO (United States); Leventhal, Michael [National Renewable Energy Lab. (NREL), Golden, CO (United States); Baring-Gould, Ian [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2013-12-01

    As wind power facilities age, project owners are faced with plant end of life decisions. This report is intended to inform policymakers and the business community regarding the history, opportunities, and challenges associated with plant end of life actions, in particular repowering. Specifically, the report details the history of repowering, examines the plant age at which repowering becomes financially attractive, and estimates the incremental market investment and supply chain demand that might result from future U.S. repowering activities.

  19. Air toxics emission from an IGCC process

    Energy Technology Data Exchange (ETDEWEB)

    Mojtahedi, W; Hovath, A [Carbona Inc, Helsinki (Finland); Hinderson, A [Vattenfall Utveckling (Sweden); Nykaenen, J; Hoffren, H [Imatran Voima Oy, Vantaa (Finland); Nieminen, M; Kurkela, E [VTT, Espoo (Finland)

    1997-10-01

    The emissions of 12 toxic trace element from a coal-fired IGCC plant were calculated based on thermodynamic equilibrium in the gas phase and some of the results published. The theoretical calculations were extended to include some other fuels as well as mixture of some of these fuels. The combustion of the product gas in the gas turbine is also considered. These simulations correspond to gasification of the fuel at 850-1050 deg C (depending on the fuel) and 1823 bar pressure. The gas composition was taken from the measured data as far as possible. In the absence of experimental data, a computer code developed for the U-Gas gasifier was used to determine the fuel gas composition. The gas was then cooled to 550 deg C in the gas cooler and filtered at this same temperature and burned in the gas turbine with an air ratio of 3.2. The results of these simulations are compared with the measured data of an experimental program designed to measure the emissions of a few selected trace elements from a 15 MW,h pressurized fluidized bed gasification pilot plant. The pilot plant was equipped with an advanced hot gas cleanup train which includes a two fluidized-bed reactor system for high-temperature, high-pressure external sulfur removal and a filtration unit housing porous, rigid ceramic candle filters. The trace element concentrations in the fuel, bottom ash, and filter ash are determined and the results compared with EPA regulatory levels

  20. Recent operating experience and improvement of commercial IGCC

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2013-09-01

    IGCC has today reached a status where experience is available from first and second generation plants, built in the 1970s/1980s and in the 1990s respectively, as commercial-scale demonstration plants for coal-based applications. These plants feature variations on gasification technology and subsequent environmental controls and in operating them a number of technical and commercial lessons have been learned that will help to improve the next generation of IGCC projects. The report reviews and summarises the state-of-the-art and operating experience of several commercial IGCC plants worldwide, setting out the lessons learned and plans for future development embracing such issues as the changes or modifications to plant made to overcome the operational problems and to improve the reliability and availability of the plant. Since IGCC is considered a 'capture ready' technology for CO2 abatement, the current status with regard to the incorporation of carbon capture and storage systems (CCS) has been reviewed. Finally, the report outlines the issues associated with assessing the risks in commercialising IGCC plant.

  1. IGCC based on proven technology developing towards 50% efficiency mark

    Energy Technology Data Exchange (ETDEWEB)

    Goudappel, E.; Berkhout, M. [Jacobs Consultancy, Leiden (Netherlands)

    2006-07-01

    In this paper the achievements made over the last 10 years in terms of reliability, load following and efficiency improvement potential at the Buggenum IGCC plant, are presented. Also the air side heat integration and its pros and cons are discussed. Additionally future business opportunities adjacent to the power production itself and the view on coal gasification in the near future are provided. The results are discussed and it is shown that with 'proven' gasifier and gas treatment technology, overall efficiency exceeding 47% (LHV basis) can be reached. It puts this technical potential in perspective and describes the view on interesting business opportunities around IGCC projects. 5 figs., 3 tabs.

  2. Exergoeconomic evaluation of a KRW-based IGCC power plant

    International Nuclear Information System (INIS)

    Tsatsavonis, G.; Lin, L.; TawFik, T.; Gallaspy, D.T.

    1991-01-01

    This paper reports on a study supported by the US Department of Energy, in which several design configurations of Kellogg-Rust-Westinghouse (KRW)-based Integrated Gasification-Combined-Cycle (IGCC) power plants were developed. One of these configurations was analyzed from the exergoeconomic (thermoeconomic) viewpoint. The detailed exergoeconomic evaluation identified several changes for improving the cost effectiveness of this IGCC design configuration. Based on the cost information supplied by the M.W. Kellogg Company, an attempt was made to calculate the economically optimal exergetic efficiency for some of the most important plant components. This information is currently used in plant optimization studies

  3. Modeling and assessment of future IGCC plant concepts with CO{sub 2} capture; Simulation und Bewertung zukuenftiger IGCC-Kraftwerkskonzepte mit CO{sub 2}-Abtrennung

    Energy Technology Data Exchange (ETDEWEB)

    Kunze, Christian A.

    2012-07-13

    The thesis focuses on the assessment of efficiency potential of future IGCC plants with CO{sub 2} capture. Starting point is a comprehensive analysis (thermodynamic, economic and exergy) of a state of the art IGCC. Additionally, five future IGCC concepts are proposed and evaluated for their efficiency potential in the mid- and long-term. The concepts showed significantly higher efficiencies up to approximately 60% and enable an almost CO{sub 2}-free operation.

  4. Advanced IGCC-Hypogen concepts for a developing hydrogen market

    Energy Technology Data Exchange (ETDEWEB)

    Starr, F.; Cormos, C.-C.; Tzimas, E.; Brown, A. [European Commission, Petten (Netherlands). DG Joint Research Centre, Institute for Energy

    2007-07-01

    With FP6 the EU is funding a project called 'Dynamis' which aims to design plants to generate electricity, plus a limited amount of hydrogen from fossil fuels, in which the CO{sub 2} is captured and stored underground. Such plants have been characterised as being of the 'HYPOGEN' type since they generate both hydrogen and electric power. As the hydrogen market develops IGCC-Hypogen based systems will need to produce much greater amounts of hydrogen. It is also desirable that such plants should be able to vary the proportion of hydrogen-to-electricity. This will enable IGCC-Hypogen plants to load follow and two-shift as electricity demand from the grid changes. Such variations in power output are not always practical with existing designs of electricity-only IGCCs. This paper reviews the technical issues involved in providing a high-flexibility IGCC-Hypogen plant. Three such concepts are discussed (1) very limited flexibility in which the changes from a fixed hydrogen-electricity ratio concept are minor, (2) moderate level of flexibility in which the limit is imposed by the CCGT gas turbine turndown (3) complete flexibility, the plant being able produce the energy as all-electricity or all-hydrogen. 9 refs., 2 figs., 1 tab.

  5. Technical and economic assessment of solar hybrid repowering. Final report

    Energy Technology Data Exchange (ETDEWEB)

    None

    1978-09-01

    Public Service Company of New Mexico (PNM) has performed a Technical and Economic Assessment of Solar Hybrid Repowering under funding by the Department of Energy (DOE), the Electric Power Research Institute (EPRI), Western Energy Supply and Transmission (WEST) Associates, and a number of southwestern utilities. Solar hybrid repowering involves placement of solar hardware adjacent to and connected to existing gas- and oil-fueled electric generation units to displace some of or all the fossil fuel normally used during daylight hours. The subject study assesses the technical economic viability of the solar hybrid repowering concept within the southwestern United States and the PNM system. This document is a final report on the study and its results. The study was divided into the six primary tasks to allow a systematic investigation of the concept: (1) market survey and cost/benefit analysis, (2) study unit selection, (3) conceptual design and cost estimates, (4) unit economic analysis, (5) program planning, future phases, and (6) program management. Reeves Station No. 2 at Albuquerque, New Mexico, was selected for repowering with a design goal of 50 percent (25 MWe). The solar system design is based on the 10 MW solar central receiver pilot plant preliminary design for Barstow, California. SAN--1608-4-2 contains the technical drawings. (WHK)

  6. Newman Unit 1 advanced solar repowering. Final report

    Energy Technology Data Exchange (ETDEWEB)

    None

    1982-04-01

    The five appendices give the selection process and system specification of the Newman Unit 1 solar repowering system, including the conceptual design drawings and diagrams; input data for the simulation program; and a review of the most important characteristics of the existing plant. (LEW)

  7. Optimizing CO2 avoided cost by means of repowering

    International Nuclear Information System (INIS)

    Escosa, Jesus M.; Romeo, Luis M.

    2009-01-01

    Repowering fossil fuel power plants by means of gas turbines has been traditionally considered to increase power output and reduce NO x and SO 2 emissions both at low cost and short outage periods. At present, reduction in CO 2 emissions represents an additional advantage of repowering due to partial fuel shift and overall efficiency increase. This is especially important in existing installations with a CO 2 reduction mandatory that should be carried out in a short time and in a cost-effective manner. Feedwater and parallel repowering schemes have been analysed using thermodynamic, environmental and economic simulations. The objective is not only to evaluate the cost of electricity and the efficiency increase of the overall system, but calculate and minimize the cost of CO 2 avoided as a function of gas turbine power output. It seems that integration of larger gas turbines reduces the overall CO 2 emissions, but there is a compromise between CO 2 reduction due to fuel shift and a optimum integration of waste heat into the power plant to minimize the CO 2 avoided costs. Results highlight the repowering as a suitable technology to reduce 10-30% of CO 2 emissions in existing power plants with cost well below 20 Euro /tCO 2 . It could help to control emissions up to the carbon capture technologies commercial development.

  8. Policies and design elements for the repowering of wind farms: A qualitative analysis of different options

    International Nuclear Information System (INIS)

    Rio, Pablo del; Calvo Silvosa, Anxo; Iglesias Gomez, Guillermo

    2011-01-01

    Repowering of a wind farm is the process of replacing existing wind turbines with new turbines that either have a larger nameplate capacity or more efficiency, resulting in a net increase of the power generated. Although repowering brings, both, social and private benefits, there are also several obstacles to repowering which justify public support. The aim of this paper is to provide an overview and a qualitative analysis of instruments and design options to support repowering of on-shore wind farms. The multicriteria analysis carried out in this paper shows that all instruments have their advantages and drawbacks. However, feed-in tariffs and investment subsidies seem to be particularly appropriate instruments in this regard. Furthermore, we provide an assessment of different design options to promote repowering according to key assessment criteria. The relevance of design elements hinges on the fact that these are the ones directly affecting the variables that are relevant in the decision to repower (capacity factors and investment costs). - Research highlights: → This paper provides a qualitative analysis of instruments and design options to support repowering in wind farms. → The multicriteria analysis has shown that all instruments have their advantages and drawbacks regarding promotion of repowering. → However, feed-in tariffs and investment subsidies seem to be particularly appropriate instruments in this regard. → The choice of design elements within instruments is at least as important to promote repowering as the choice of specific instruments.

  9. THERMAL AND SINTERING CHARACTERIZATION OF A IGCC SLAG

    OpenAIRE

    Acosta, Anselmo; Iglesias, Isabel; Aineto, Mónica; Romero, Maximina; Rincón López, Jesús María

    2002-01-01

    IGCC slag is a vitreous residual product from the new induction gasification combined cycle gasification thermal power plants. In order to characterize this waste as secondary new material for the production of new glasses and glass-ceramics as construction materials; this slag from the Puertollano, Ciudad Real, Spain power plants has been fully thermally investigated. After controlled heating this waste gives rise to hematite, anorthite, and cristobalite crystallized materials.

  10. Tampa Electric Company Polk Power Station IGCC project: Project status

    Energy Technology Data Exchange (ETDEWEB)

    McDaniel, J.E.; Carlson, M.R.; Hurd, R.; Pless, D.E.; Grant, M.D. [Tampa Electric Co., FL (United States)

    1997-12-31

    The Tampa Electric Company Polk Power Station is a nominal 250 MW (net) Integrated Gasification Combined Cycle (IGCC) power plant located to the southeast of Tampa, Florida in Polk County, Florida. This project is being partially funded under the Department of Energy`s Clean Coal Technology Program pursuant to a Round II award. The Polk Power Station uses oxygen-blown, entrained-flow IGCC technology licensed from Texaco Development Corporation to demonstrate significant reductions of SO{sub 2} and NO{sub x} emissions when compared to existing and future conventional coal-fired power plants. In addition, this project demonstrates the technical feasibility of commercial scale IGCC and Hot Gas Clean Up (HGCU) technology. The Polk Power Station achieved ``first fire`` of the gasification system on schedule in mid-July, 1996. Since that time, significant advances have occurred in the operation of the entire IGCC train. This paper addresses the operating experiences which occurred in the start-up and shakedown phase of the plant. Also, with the plant being declared in commercial operation as of September 30, 1996, the paper discusses the challenges encountered in the early phases of commercial operation. Finally, the future plans for improving the reliability and efficiency of the Unit in the first quarter of 1997 and beyond, as well as plans for future alternate fuel test burns, are detailed. The presentation features an up-to-the-minute update on actual performance parameters achieved by the Polk Power Station. These parameters include overall Unit capacity, heat rate, and availability. In addition, the current status of the start-up activities for the HGCU portion of the plant is discussed.

  11. Kemper County IGCC (tm) Project Preliminary Public Design Report

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, Matt; Rush, Randall; Madden, Diane; Pinkston, Tim; Lunsford, Landon

    2012-07-01

    The Kemper County IGCC Project is an advanced coal technology project that is being developed by Mississippi Power Company (MPC). The project is a lignite-fueled 2-on-1 Integrated Gasification Combined-Cycle (IGCC) facility incorporating the air-blown Transport Integrated Gasification (TRIG™) technology jointly developed by Southern Company; Kellogg, Brown, and Root (KBR); and the United States Department of Energy (DOE) at the Power Systems Development Facility (PSDF) in Wilsonville, Alabama. The estimated nameplate capacity of the plant will be 830 MW with a peak net output capability of 582 MW. As a result of advanced emissions control equipment, the facility will produce marketable byproducts of ammonia, sulfuric acid, and carbon dioxide. 65 percent of the carbon dioxide (CO{sub 2}) will be captured and used for enhanced oil recovery (EOR), making the Kemper County facility’s carbon emissions comparable to those of a natural-gas-fired combined cycle power plant. The commercial operation date (COD) of the Kemper County IGCC plant will be May 2014. This report describes the basic design and function of the plant as determined at the end of the Front End Engineering Design (FEED) phase of the project.

  12. Wabash River coal gasification repowering project -- first year operation experience

    Energy Technology Data Exchange (ETDEWEB)

    Troxclair, E.J. [Destec Energy, Inc., Houston, TX (United States); Stultz, J. [PSI Energy, Inc., West Terre Haute, IN (United States)

    1997-12-31

    The Wabash River Coal Gasification Repowering Project (WRCGRP), a joint venture between Destec Energy, Inc. and PSI Energy, Inc., began commercial operation in November of 1995. The Project, selected by the United States Department of Energy (DOE) under the Clean Coal Program (Round IV) represents the largest operating coal gasification combined cycle plant in the world. This Demonstration Project has allowed PSI Energy to repower a 1950`s vintage steam turbine and install a new syngas fired combustion turbine to provide 262 MW (net) of electricity in a clean, efficient manner in a commercial utility setting while utilizing locally mined high sulfur Indiana bituminous coal. In doing so, the Project is also demonstrating some novel technology while advancing the commercialization of integrated coal gasification combined cycle technology. This paper discusses the first year operation experience of the Wabash Project, focusing on the progress towards achievement of the demonstration objectives.

  13. Repowering analysis: Hanford Generating Project (HGP), Task Order Number 6

    International Nuclear Information System (INIS)

    1988-12-01

    The Hanford Generating Project (HGP), owned by the Washington Public Power Supply System, consists of two low pressure steam turbines, generators, and associated equipment located adjacent to the Department of Energy's (DOE) N-Reactor. HGP has been able to produce approximately 800 MWe with low pressure steam supplied by N-Reactor. DOE has placed N-Reactor in cold standby status for an undetermined length of time. This results in the idling of the HGP since no alternative source of steam is available. Bonneville Power Administration contracted with Fluor Daniel, Inc. to investigate the feasibility and cost of constructing a new source of steam for (repowering) one of the HGP turbines. The steam turbine is currently operated with 135 psia steam. The turbines can be rebuilt to operate with 500 psia steam pressure by adding additional stages, buckets, nozzles, and diaphragms. Because of the low pressure design, this turbine can never achieve the efficiencies possible in new high pressure turbines by the presences of existing equipment reduces the capital cost of a new generating resource. Five repowering options were investigated in this study. Three cases utilizing gas turbine combined cycle steam generation equipment, one case utilizing a gas fired boiler, and a case utilizing a coal fired boiler. This report presents Fluor Daniel's analysis of these repowering options

  14. Comparison of Shell, Texaco, BGL and KRW gasifiers as part of IGCC plant computer simulations

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, L.; Furimsky, E. [Natural Resources Canada, Ottawa, ON (Canada). CANMET Energy Technology Centre

    2005-07-01

    The performances of four IGCC plants employing Shell, Texaco, BGL and KRW gasifiers were simulated using ASPEN Plus software for three different feeds. Performance analyses and comparisons of all four IGCC plants were performed based on the established data bank from the simulation. Discussions were focused on gas compositions, gasifier selection and overall performance.

  15. RWE clean coal programme - IGCC power plant with CO{sub 2} capture & storage

    Energy Technology Data Exchange (ETDEWEB)

    Wolf, K.-J.; Ewers, J.; Renzenbrink, W. [RWE Power AG, Essen (Germany)

    2007-07-01

    In early 2006, RWE Power announced it was building a 450 MW gross commercial IGCC power plant with carbon capture. This paper sums up the key results of the project development phase concerning the IGCC power plant and shows the basis for the feasibility phase of the project. 10 figs.

  16. Developments in the pre-combustion CO2 capture pilot plant at the Buggenum IGCC

    NARCIS (Netherlands)

    Damen, K.; Gnutek, R.; Kaptein, J.; Nannan, N.R.; Oyarzun, B.; Trapp, C.; Colonna, P.; Van Dijk, E.; Gross, J.; Bardow, A.

    2011-01-01

    N.V. Nuon (part of the Vattenfall Group) operates an IGCC in Buggenum and is developing a multi-fuel IGCC with CO2 capture and storage (Nuon Magnum) in Eemshaven, the Netherlands. In order to prepare for large-scale application of CO2 capture and storage, a CO2 capture pilot plant is constructed at

  17. IGCC - fuel-flexible technology for the future

    Energy Technology Data Exchange (ETDEWEB)

    Karg, J.; Hannemann, F. [Siemens AG Power Generation, Erlangen (Germany)

    2004-07-01

    According to IEA's World Energy Investment Outlook 2003 the electricity sector will dominate with about 60% of the total investment requirements expected until 2030 for worldwide energy-supply infrastructure. Around 45% of the capital needed for the electricity sector will be for power generation. The investment will be needed for capacity additions and to replace existing older facilities. According to the estimates the global primary energy demand is projected to grow by two thirds over the next three decades and electricity demand is expected to double by 2030. The natural gas for power generation is projected to increase significantly, but coal will remain the largest source of electricity generation throughout the projection period. These trends must be seen against the background that environmental regulations, are becoming tighter, and that environmental legislation will increasingly address greenhouse gas emissions. The necessity for more efficient use of primary energies in combination with more stringent environmental regulations for fossil-fuelled power plants therefore pushes concepts with increased efficiencies and reduced CO{sub 2} emissions, respectively. Since significant reduction of CO{sub 2} emissions cannot only be achieved via increased efficiencies or application of fuels with low carbon content, CO{sub 2} removal options also need to be considered for future power plant configurations. Considering this, IGCC is again one of the most promising solutions which are of relevance in this context. However, these new IGCC applications require further overall a plant concept and component development efforts. One essential step for performance improvement of future IGCC applications is to further develop syngas capabilities of advanced gas turbines, thereby considering the experience and lessons learned from operational plants. 11 refs., 7 figs., 5 tabs.

  18. CERAMIC MEMBRANE ENABLING TECHNOLOGY FOR IMPROVED IGCC EFFICIENCY

    International Nuclear Information System (INIS)

    Ravi Prasad

    2000-01-01

    The objective of this program is to conduct a technology development program to advance the state-of-the-art in ceramic Oxygen Transport Membranes (OTM) to the level required to produce step change improvements in process economics, efficiency, and environmental benefits for commercial IGCC systems and other applications. The IGCC program is focused on addressing key issues in materials, processing, manufacturing, engineering and system development that will make the OTM a commercial reality. The objective of the OTM materials development task is to identify a suitable material that can be formed into a thin film to produce the target oxygen flux. This requires that the material have an adequate permeation rate, and thermo-mechanical and thermo-chemical properties such that the material is able to be supported on the desired substrate and sufficient mechanical strength to survive the stresses involved in operation. The objective of the composite OTM development task is to develop the architecture and fabrication techniques necessary to construct stable, high performance, thin film OTMs supported on suitable porous, load bearing substrates. The objective of the process development task of this program to demonstrate the program objectives on a single OTM tube under test conditions simulating those of the optimum process cycle for the power plant

  19. Pre-Combustion Capture of CO2 in IGCC Plants

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2011-12-15

    Pre-combustion capture involves reacting a fuel with oxygen or air and/or steam to give mainly a 'synthesis gas (syngas)' or 'fuel gas' composed of carbon monoxide and hydrogen. The carbon monoxide is reacted with steam in a catalytic reactor, called a shift converter, to produce CO2 and more hydrogen. CO2 is then separated, usually by a physical or chemical absorption process, resulting in a hydrogen-rich fuel which can be used in many applications, such as boilers, furnaces, gas turbines, engines and fuel cells. Pre-combustion capture is suitable for use in integrated gasification combined cycle (IGCC) plants especially since the CO2 partial pressures in the fuel gas are higher than in the flue gas. After the introduction there follows a short discussion of the water-gas shift (WGS) reaction. This is followed by chapters on the means of CO2 capture by physical and chemical solvents, solid sorbents, and membranes. The results and conclusions of techno-economic studies are introduced followed by a look at some of the pilot and demonstration plants relevant to pre-combustion capture in IGCC plants.

  20. ConocoPhillips Sweeny IGCC/CCS Project

    Energy Technology Data Exchange (ETDEWEB)

    Paul Talarico; Charles Sugg; Thomas Hren; Lauri Branch; Joseph Garcia; Alan Rezigh; Michelle Pittenger; Kathleen Bower; Jonathan Philley; Michael Culligan; Jeremy Maslen; Michele Woods; Kevin Elm

    2010-06-16

    Under its Industrial Carbon Capture and Sequestration (ICCS) Program, the United States (U.S.) Department of Energy (DOE) selected ConocoPhillips Company (ConocoPhillips) to receive funding through the American Recovery and Reinvestment Act (ARRA) of 2009 for the proposed Sweeny Integrated Gasification Combined Cycle (IGCC)/Carbon Capture and Storage (CCS) Project (Project) to be located in Brazoria County, Texas. Under the program, the DOE is partnering with industry to demonstrate the commercial viability and operational readiness of technologies that would capture carbon dioxide (CO{sub 2}) emissions from industrial sources and either sequester those emissions, or beneficially reuse them. The primary objective of the proposed Project was to demonstrate the efficacy of advanced technologies that capture CO{sub 2} from a large industrial source and store the CO{sub 2} in underground formations, while achieving a successful business venture for the entity (entities) involved. The Project would capture 85% of the CO{sub 2} produced from a petroleum coke (petcoke) fed, 703 MWnet (1,000 MWgross) IGCC power plant, using the ConocoPhillips (COP) proprietary and commercially proven E-Gas{trademark} gasification technology, at the existing 247,000 barrel per day COP Sweeny Refinery. In addition, a number of other commercially available technologies would be integrated into a conventional IGCC Plant in a unique, efficient, and reliable design that would capture CO{sub 2}. The primary destination for the CO{sub 2} would be a depleted natural gas field suitable for CO{sub 2} storage ('Storage Facility'). COP would also develop commercial options to sell a portion of the IGCC Plant's CO{sub 2} output to the growing Gulf Coast enhanced oil recovery (EOR) market. The IGCC Plant would produce electric power for sale in the Electric Reliability Council of Texas Houston Zone. The existing refinery effluent water would be treated and reused to fulfill all process

  1. Integrated assessment of IGCC power generation technology with carbon capture and storage (CCS)

    International Nuclear Information System (INIS)

    Cormos, Calin-Cristian

    2012-01-01

    IGCC (Integrated Gasification Combined Cycle) is a power generation technology in which the solid feedstock is partially oxidized with oxygen and steam to produce syngas. In a conventional IGCC design without carbon capture, the syngas is purified for dust and hydrogen sulphide removal and then it is sent to a CCGT (Combined Cycle Gas Turbine) for power generation. CCS (Carbon capture and storage) technologies are expected to play a significant role in the coming decades for reducing the greenhouse gas emissions. IGCC is one of the power generation technologies having the highest potential to capture CO 2 with low penalties in term of plant energy efficiency, capital and operational costs. This paper investigates the most important techno-economic and environmental indicators (e.g. power output, ancillary consumption, energy efficiency, CW consumption, normalised mass and energy balances and plant construction materials, capital and O and M (operational and maintenance) costs, specific CO 2 emissions, cost of electricity, CO 2 removal and avoidance costs etc.) for IGCC with CCS. Coal-based IGCC cases produce around 400–450 MW net electricity with 90% carbon capture rate. Similar IGCC plants without CCS were presented as references. Future IGCC developments for energy vectors poly-generation were also presented. -- Highlights: ► Techno-economical evaluations of coal-based IGCC power generation with CCS. ► Model development for capital, O and M, CO 2 capture costs and cash flow estimations. ► Technical and economic investigations of key plant design characteristics. ► Evaluations of carbon capture options for IGCC power generation technology.

  2. Re-powering and site recycling in a competitive environment

    International Nuclear Information System (INIS)

    Taylor, A.; Kahn, E.P.

    1991-03-01

    Re-powering and site recycling are strategies designed to expand electric generating capacity by using depreciated assets. The resource base for the these strategies is large. By 1995, over 170,000 MW of fossil-fired capacity will be in excess of thirty years old, and approaching the end of its conventional economic lifetime. This paper explores how these assets might be developed using competitive market forces. While some re-powering is being pursued under traditional ratebase regulation, there are four other generic alternatives. These are: (1) utility investment at fixed prices with regulatory pre-approval, (2) utility investment under competitive bidding, (3) utility leasing for private producer development, and (4) utility sale of sites for private producer development. Issues associated with each alternative are explored and illustrated with examples. State regulatory policy will be the critical determinant of whether a market develops for depreciated power plants. Financial incentives will stimulate utilities to re-deploy depreciated assets. This means some form of profit-sharing between customers and shareholders of the grains from asset sales. Different approaches to profit sharing are reviewed. These developments are still in an experimental state, however, and no single approach appears to have emerged as a dominant trend. 36 refs., 1 tab

  3. Exergetic comparison of two KRW-based IGCC power plants

    International Nuclear Information System (INIS)

    Tsatsaronis, G.; Tawfik, T.; Lin, L.; Gallaspy, D.T.

    1991-01-01

    In studies supported by the U.S. Department of Energy and the Electric Power Research Institute, several design configurations of Kellogg-Rust-Westinghouse (KRW)-based Integrated Gasification-Combined-Cycle (IGCC) power plants were developed. Two of these configurations are compared in this paper, from the exergetic viewpoint. The exergetic comparison identifies the causes of performance differences between the two cases: differences in the exergy destruction of the gasification system, the gas turbine system, and the gas cooling process, as well as differences in the exergy loss accompanying the solids to disposal stream. The potential for using oxygen-blown versus air-blown KRW gasifiers, and hot gas versus cold gas cleanup processes is evaluated

  4. Repowering of an Existing Power Plant by Means of Gas Turbine and Solid Oxide Fuel Cell

    DEFF Research Database (Denmark)

    Rokni, Masoud

    2014-01-01

    Repowering is a process consisting in a transformation of an old power plant in order to have a greater nameplate capacity or more efficiency, which result in a net increase of power generated. As a consequence of the higher efficiency, the repow ered plant is characterized by higher power output...... and less specific CO2 emissions. Usually, a repowering is performed adding one or more gas turbines to an existing steam cycle which was built decades ago. Thus, traditional repowering results in combine d cycles (CC). High temperature fuel cells (such as SOFC) could also be used as a topping cycle......, reaching global plant efficiency even higher and specific CO2 emissions even lower. Decreasing the operating temperature in a SOFC allows the use of less compl ex materials and construction methods, consequently reducing plant and the electricity cost. A lower working temperature makes it also suitable...

  5. Technical and economic assessment of solar hybrid repowering: conceptual design and cost estimate

    Energy Technology Data Exchange (ETDEWEB)

    None

    1978-09-01

    This volume contains the appendix to the conceptual design and cost estimate report on solar repowering the Reeves Unit No. 2 power plant in Albuquerque, New Mexico. Included are the engineering drawings and the work breakdown structure estimate report. (WHK)

  6. CO{sub 2}-capture in coal based IGCC power plants

    Energy Technology Data Exchange (ETDEWEB)

    Van Aart, F.; Fleuren, W.; Kamphuis, H.; Ploumen, P.; Jelles, S. [KEMA, Arnhem (Netherlands)

    2007-07-01

    The paper discusses IGCC with carbon capture and storage (CCS), both for retrofit and capture ready plants. The penalties for carbon dioxide capture are given, along with its effect on CAPEX and OPEC costs. 3 refs., 9 figs.

  7. Enabling Technology for Monitoring & Predicting Gas Turbine Health & Performance in IGCC Powerplants

    Energy Technology Data Exchange (ETDEWEB)

    Kenneth A. Yackly

    2005-12-01

    The ''Enabling & Information Technology To Increase RAM for Advanced Powerplants'' program, by DOE request, was re-directed, de-scoped to two tasks, shortened to a 2-year period of performance, and refocused to develop, validate and accelerate the commercial use of enabling materials technologies and sensors for coal/IGCC powerplants. The new program was re-titled ''Enabling Technology for Monitoring & Predicting Gas Turbine Health & Performance in IGCC Powerplants''. This final report summarizes the work accomplished from March 1, 2003 to March 31, 2004 on the four original tasks, and the work accomplished from April 1, 2004 to July 30, 2005 on the two re-directed tasks. The program Tasks are summarized below: Task 1--IGCC Environmental Impact on high Temperature Materials: The first task was refocused to address IGCC environmental impacts on high temperature materials used in gas turbines. This task screened material performance and quantified the effects of high temperature erosion and corrosion of hot gas path materials in coal/IGCC applications. The materials of interest included those in current service as well as advanced, high-performance alloys and coatings. Task 2--Material In-Service Health Monitoring: The second task was reduced in scope to demonstrate new technologies to determine the inservice health of advanced technology coal/IGCC powerplants. The task focused on two critical sensing needs for advanced coal/IGCC gas turbines: (1) Fuel Quality Sensor to rapidly determine the fuel heating value for more precise control of the gas turbine, and detection of fuel impurities that could lead to rapid component degradation. (2) Infra-Red Pyrometer to continuously measure the temperature of gas turbine buckets, nozzles, and combustor hardware. Task 3--Advanced Methods for Combustion Monitoring and Control: The third task was originally to develop and validate advanced monitoring and control methods for coal/IGCC gas

  8. Recycling of residual IGCC slags and their benefits as degreasers in ceramics.

    Science.gov (United States)

    Iglesias Martín, I; Acosta Echeverría, A; García-Romero, E

    2013-11-15

    This work studies the evolution of IGCC slag grains within a ceramic matrix fired at different temperatures to investigate the effect of using IGCC slag as a degreaser. Pressed ceramic specimens from two clay mixtures are used in this study. The M1 mixture is composed of standard clays, whereas the M2 mixture is composed of the same clay mixture as M1 mixture but contains 15% by weight IGCC slag. The amount of IGCC slag added coincides with the amount of slag typically used as a degreaser in the ceramic industry. Specimens are fired at 950 °C, 1000 °C, 1050 °C, 1100 °C and 1150 °C. The mineralogical composition and the IGCC slag grain shape within the ceramic matrix are determined by X-ray diffraction, polarized light microscopy and scanning electron microscopy. The results reveal that the surface of the slag grains is welded to the ceramic matrix while the quartz grains are separated, which causes increased water absorption and reduces the mechanical strength. IGCC slag, however, reduces water absorption. This behaviour is due to the softening temperature of the slag. This property is quite important from an industrial viewpoint because IGCC slag can serve as an alternative to traditional degreasing agents in the ceramic building industry. Additionally, using IGCC slag allows for the transformation of waste into a secondary raw material, thereby avoiding disposal at landfills; moreover, these industrial wastes are made inert and improve the properties of ceramics. Copyright © 2013 Elsevier Ltd. All rights reserved.

  9. Dynamic simulation of operating cases and malfunctions of an IGCC power plant system

    Energy Technology Data Exchange (ETDEWEB)

    Koch, I.; Hannemann, F. [Siemens AG, Power Generation (KWU), Erlangen (Germany); Hoffmann, U. [Technische Univ. Clausthal, Clausthal-Zellerfeld (Germany). Inst. fuer Chemische Verfahrenstechnik

    1999-07-01

    Fully integrated IGCC plants consist of several units. This novel integration of various plant systems places stiff new requirements on power plant design, as prediction of operating and faulted behavior is made more difficult by many different interactions. This is especially the case for the gas turbine fuel system in an IGCC power plant, as it affects and is affected by all of the other major plant systems. (orig.)

  10. Enabling Technology for Monitoring & Predicting Gas Turbine Health & Performance in COAL IGCC Powerplants

    Energy Technology Data Exchange (ETDEWEB)

    Kenneth A. Yackly

    2004-09-30

    The ''Enabling & Information Technology To Increase RAM for Advanced Powerplants'' program, by DOE request, has been re-directed, de-scoped to two tasks, shortened to a 2-year period of performance, and refocused to develop, validate and accelerate the commercial use of enabling materials technologies and sensors for Coal IGCC powerplants. The new program has been re-titled as ''Enabling Technology for Monitoring & Predicting Gas Turbine Health & Performance in IGCC Powerplants'' to better match the new scope. This technical progress report summarizes the work accomplished in the reporting period April 1, 2004 to August 31, 2004 on the revised Re-Directed and De-Scoped program activity. The program Tasks are: Task 1--IGCC Environmental Impact on high Temperature Materials: This first materials task has been refocused to address Coal IGCC environmental impacts on high temperature materials use in gas turbines and remains in the program. This task will screen material performance and quantify the effects of high temperature erosion and corrosion of hot gas path materials in Coal IGCC applications. The materials of interest will include those in current service as well as advanced, high-performance alloys and coatings. Task 2--Material In-Service Health Monitoring: This second task develops and demonstrates new sensor technologies to determine the in-service health of advanced technology Coal IGCC powerplants, and remains in the program with a reduced scope. Its focus is now on only two critical sensor need areas for advanced Coal IGCC gas turbines: (1) Fuel Quality Sensor for detection of fuel impurities that could lead to rapid component degradation, and a Fuel Heating Value Sensor to rapidly determine the fuel heating value for more precise control of the gas turbine, and (2) Infra-Red Pyrometer to continuously measure the temperature of gas turbine buckets, nozzles, and combustor hardware.

  11. Feasibility studies to improve plant availability and reduce total installed cost in IGCC plants

    Energy Technology Data Exchange (ETDEWEB)

    Sullivan, Kevin [General Electric Company, Houston, TX (United States); Anasti, William [General Electric Company, Houston, TX (United States); Fang, Yichuan [General Electric Company, Houston, TX (United States); Subramanyan, Karthik [General Electric Company, Houston, TX (United States); Leininger, Tom [General Electric Company, Houston, TX (United States); Zemsky, Christine [General Electric Company, Houston, TX (United States)

    2015-03-30

    The main purpose of this project is to look at technologies and philosophies that would help reduce the costs of an Integrated Gasification Combined Cycle (IGCC) plant, increase its availability or do both. GE’s approach to this problem is to consider options in three different areas: 1) technology evaluations and development; 2) constructability approaches; and 3) design and operation methodologies. Five separate tasks were identified that fall under the three areas: Task 2 – Integrated Operations Philosophy; Task 3 – Slip Forming of IGCC Components; Task 4 – Modularization of IGCC Components; Task 5 – Fouling Removal; and Task 6 – Improved Slag Handling. Overall, this project produced results on many fronts. Some of the ideas could be utilized immediately by those seeking to build an IGCC plant in the near future. These include the considerations from the Integrated Operations Philosophy task and the different construction techniques of Slip Forming and Modularization (especially if the proposed site is in a remote location or has a lack of a skilled workforce). Other results include ideas for promising technologies that require further development and testing to realize their full potential and be available for commercial operation. In both areas GE considers this project to be a success in identifying areas outside the core IGCC plant systems that are ripe for cost reduction and ity improvement opportunities.

  12. Recovery of flue gas energy in heat-integrated gasification combined cycle (IGCC) power plants using the contact economizer system

    CSIR Research Space (South Africa)

    Madzivhandila, VA

    2011-03-01

    Full Text Available (flue gas) stream of a heat-integrated gasification combined cycle (IGCC) design of the Elcogas plant adopted from previous studies. The underlying support for this idea was the direct relationship between efficiency of the IGCC and the boiler feedwater...

  13. Briefing Book, Interagency Geothermal Coordinating Council (IGCC) Meeting of April 28, 1988

    Energy Technology Data Exchange (ETDEWEB)

    None

    1988-04-28

    The IGCC of the U.S. government was created under the intent of Public Law 93-410 (1974) to serve as a forum for the discussion of Federal plans, activities, and policies that are related to or impact on geothermal energy. Eight Federal Departments were represented on the IGCC at the time of this meeting. The main presentations in this report were on: Department of Energy Geothermal R&D Program, the Ormat binary power plant at East Mesa, CA, Potential for direct use of geothermal at Defense bases in U.S. and overseas, Department of Defense Geothermal Program at China Lake, and Status of the U.S. Geothermal Industry. The IGCC briefing books and minutes provide a historical snapshot of what development and impact issues were important at various time. (DJE 2005)

  14. A comparison of improved power plant technologies on lignite with (PFBC) and (IGCC) cycles

    International Nuclear Information System (INIS)

    Cherepnalkovski, Ilija

    1997-01-01

    Technologies and process diagrams descriptions for PFBC (Pressurised Fluidized Bed Combustion) and IGCC (Integrated Gasification Combined Cycle) are presented as for improved cycles with modern clean coal technologies, the most popular currently. A special attention is paid to the possibilities for Macedonian lignites use on the power plants with PFBC and IGCC cycles. The comparison of the above mention technologies has been done particularly on the desulfurization, NO x reduction, ash elimination and its use in the building and construction industries. A comparison between the power plants with PFBC and IGCC cycles is made by the following criteria: cycle efficiency, desulfurization and nitrogen oxides reduction, power plant complexity and their cost, as well as plant reliability. (Author)

  15. Comprehensive report to Congress, Clean Coal Technology program: Pinon Pine IGCC Power Project

    International Nuclear Information System (INIS)

    1992-06-01

    The objective of the proposed project is to demonstrate an advanced IGCC system based upon the air-blown, fluidized-bed KRW gasifier with in-bed desulfurization using limestone sorbent and an external fixed- bed zinc ferrite sulfur removal system. Sierra Pacific Power Company (SPPC) requested financial assistance from DOE for the design, construction, and operation of a nominal 800 ton-per-day (86-Megawatt gross), air blown integrated gasification combined-cycle (IGCC) demonstration plant. The project, named the Pinon Pine IGCC Power Project, is to be located at SPPC's Tracy Station, a power generation facility located on a rural 400-acre plot about 17 miles east of Reno. The demonstration plant will produce electrical power for the utility grid. The project, including the demonstration phase, will last 96 months at a total cost of $269,993,100. DOE's share of the project cost will be 50 percent, or $134,996,550

  16. Assessment of oxy-fuel, pre- and post-combustion-based carbon capture for future IGCC plants

    International Nuclear Information System (INIS)

    Kunze, Christian; Spliethoff, Hartmut

    2012-01-01

    Highlights: ► Hot gas cleanup is a highly favorable technology for all selected IGCC concepts. ► Proposed high pressure IGCC with membrane reactor enables direct CO 2 condensation. ► IGCC with OTM and carbonate looping enable significant synergy effects. ► Combining IGCC and oxy-fuel is technically challenging but energetically favorable. ► All selected IGCC concepts are able to realize CO 2 capture rates up to 99%. -- Abstract: Environmental damage due to the emission of greenhouse gases from conventional coal-based power plants is a growing concern. Various carbon capture strategies to minimize CO 2 emissions are currently being investigated. Unfortunately, the efficiency drop due to de-carbonization is still significant and the capture rate is limited. Therefore three future hard coal IGCC concepts are assessed here, applying emerging technologies and various carbon capture approaches. The advanced pre-combustion capture concept is based on hot gas clean-up, membrane-enhanced CO conversion and direct CO 2 condensation. The concept reached a net efficiency of 45.1% (LHV), representing an improvement of 6.46% compared to the conventional IGCC base case. The second IGCC concept, based on post-combustion capture via calcination–carbonation loops, hot gas clean-up and oxygen membranes, showed a net efficiency of 45.87% (LHV). The third IGCC concept applies hot gas clean-up and combustion of the unconverted fuel gas using pure oxygen. The oxygen is supplied by an integrated oxygen membrane. The combination of IGCC and oxy-fuel process reached a net efficiency of 45.74% (LHV). In addition to their increased efficiency, all of the concepts showed significantly improved carbon capture rates up to 99%, resulting in virtually carbon-free fossil power plants.

  17. Recovery of flue gas energy in heat integrated IGCC power plants using the contact economizer system

    CSIR Research Space (South Africa)

    Madzivhandila, V

    2010-10-01

    Full Text Available Asia Pacific Confederation of APCChE 2010 Chemical Engineering Congress October 5-8, 2010, Taipei � �� Recovery of flue gas energy in heat integrated IGCC power plants using the contact economizer system Vhutshilo Madzivhandilaa, Thokozani... temperature and the thermal efficiency of the plant. The 13th Asia Pacific Confederation of APCChE 2010 Chemical Engineering Congress October 5-8, 2010, Taipei � �� 1. Introduction The IGCC (Integrated Gasification Combined Cycle) is one...

  18. What Fleets Need to Know About Alternative Fuel Vehicle Conversions, Retrofits, and Repowers

    Energy Technology Data Exchange (ETDEWEB)

    Kelly, K.; Gonzales, J.

    2017-10-02

    Many fleet managers have opted to incorporate alternative fuels and advanced vehicles into their lineup. Original equipment manufacturers (OEMs) offer a variety of choices, and there are additional options offered by aftermarket companies. There are also a myriad of ways that existing vehicles can be modified to utilize alternative fuels and other advanced technologies. Vehicle conversions and retrofit packages, along with engine repower options, can offer an ideal way to lower vehicle operating costs. This can result in long term return on investment, in addition to helping fleet managers achieve emissions and environmental goals. This report summarizes the various factors to consider when pursuing a conversion, retrofit, or repower option.

  19. What Fleets Need to Know About Alternative Fuel Vehicle Conversions, Retrofits, and Repowers

    Energy Technology Data Exchange (ETDEWEB)

    Kelly, Kay L. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Gonzales, John [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2017-10-17

    Many fleet managers have opted to incorporate alternative fuels and advanced vehicles into their lineup. Original equipment manufacturers (OEMs) offer a variety of choices, and there are additional options offered by aftermarket companies. There are also a myriad of ways that existing vehicles can be modified to utilize alternative fuels and other advanced technologies. Vehicle conversions and retrofit packages, along with engine repower options, can offer an ideal way to lower vehicle operating costs. This can result in long term return on investment, in addition to helping fleet managers achieve emissions and environmental goals. This report summarizes the various factors to consider when pursuing a conversion, retrofit, or repower option.

  20. Repowering: How to get more from existing resources to meet future power generation needs

    International Nuclear Information System (INIS)

    Bretz, E.A.

    1994-01-01

    Electric-utility executives looking to improve the profitability of their companies often focus on maximizing the output and performance of fossil-fueled powerplants. Repowering is one way to achieve the goal. The marketing and regulatory stimuli behind repowering hinge on the significant costs associated with alternative greenfield power-generation facilities for new capacity and with system-wide compliance with clear-air legislation, as well as the effects of a regulatory-driven industry embroiled in a shifting regulatory and market-driven environment. 3 figs., 2 tabs

  1. Evaluation of Suitability of Selected Set of Coal Plant Sites for Repowering with Small Modular Reactors

    Energy Technology Data Exchange (ETDEWEB)

    Belles, Randy [ORNL; Copinger, Donald A [ORNL; Mays, Gary T [ORNL; Omitaomu, Olufemi A [ORNL; Poore III, Willis P [ORNL

    2013-03-01

    This report summarizes the approach that ORNL developed for screening a sample set of small coal stations for possible repowering with SMRs; the methodology employed, including spatial modeling; and initial results for these sample plants. The objective in conducting this type of siting evaluation is to demonstrate the capability to characterize specific sample coal plant sites to identify any particular issues associated with repowering existing coal stations with SMRs using OR-SAGE; it is not intended to be a definitive assessment per se as to the absolute suitability of any particular site.

  2. Performance Comparison on Repowering of a Steam Power Plant with Gas Turbines and Solid Oxide Fuel Cells

    DEFF Research Database (Denmark)

    Rokni, Masoud

    2016-01-01

    Repowering is a process for transforming an old power plant for greater capacity and/or higher efficiency. As a consequence, the repowered plant is characterized by higher power output and less specific CO2 emissions. Usually, repowering is performed by adding one or more gas turbines into an exi......Repowering is a process for transforming an old power plant for greater capacity and/or higher efficiency. As a consequence, the repowered plant is characterized by higher power output and less specific CO2 emissions. Usually, repowering is performed by adding one or more gas turbines...... into an existing steam cycle which was built decades ago. Thus, traditional repowering results in combined cycles (CC). High temperature fuel cells (such as solid oxide fuel cell (SOFC)) could also be used as a topping cycle, achieving even higher global plant efficiency and even lower specific CO2 emissions....... Decreasing the operating temperature in a SOFC allows the use of less complex materials and construction methods, consequently reducing plant and the electricity costs. A lower working temperature makes it also suitable for topping an existing steam cycle, instead of gas turbines. This is also the target...

  3. Technical comparison between Integrated Gasification Combined Cycle (IGCC) and Natural Gas Combined Cycle (NGCC) power plants

    Energy Technology Data Exchange (ETDEWEB)

    Ortiz, Pablo Andres Silva; Venturini, Osvaldo Jose; Lora, Electo Eduardo Silva [Federal University of Itajuba - UNIFEI, MG (Brazil). Excellence Group in Thermal Power and Distributed Generation - NEST], e-mails: osvaldo@unifei.edu.br, electo@unifei.edu.br

    2010-07-01

    Among the emerging clean coal technologies for power generation, Integrated Gasification Combined Cycle (IGCC) and Natural Gas Combined Cycle (NGCC) systems are receiving considerable attention as a potentially attractive option to reduce the emissions of greenhouse gases (GHG). The main reason is because these systems has high efficiency and low emissions in comparison with traditional power generation plants. Currently in IGCC and NGCC systems at demonstration stage is been considered to implement CCS technology. CO{sub 2} emissions can be avoided in a gasification-based power plant because by transferring almost all carbon compounds to CO{sub 2} through the water gas shift (WGS) reaction, then removing the CO{sub 2} before it is diluted in the combustion stage. The aim of this study is to compare the technical performance of an IGCC system that uses Brazilian coal and petroleum coke as fuel with a NGCC system, with the same fixed output power of 450 MW. The first section of this paper presents the plant configurations of IGCC systems. The following section presents an analysis of NGCC technology. (author)

  4. Tampa electric company - IGCC project. Quarterly report, January 1, 1996--March 31, 1996

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-02-01

    This quarterly report consists of materials presented at a recent review of the project. The project is an IGCC project being conducted by Tampa Electric Company. The report describes the status of the facility construction, components, operations staff training, and discusses aspects of the project which may impact the final scheduled completion.

  5. 76 FR 13349 - Notice of Funding Availability (NOFA) for Repowering Assistance Payments to Eligible Biorefineries

    Science.gov (United States)

    2011-03-11

    ... Funding Availability (NOFA) for Repowering Assistance Payments to Eligible Biorefineries AGENCY: Rural... announces the acceptance of applications for payments to eligible biorefineries to encourage the use of... operation of these eligible biorefineries. To be eligible for payments, biorefineries must have been in...

  6. Hybrid repowering of transformers using aramids; Repotenciacao hibrida de transformadores com utilizacao de aramida

    Energy Technology Data Exchange (ETDEWEB)

    Neri Junior, Almir Laranjeira; Correia, Fidelis Botelho [Petroleo Brasileiro S.A. (PETROBRAS), Rio de Janeiro, RJ (Brazil)

    2010-01-15

    Santiago substation of the PETROBRAS, operated with two transformers fabricated in 1971. To preserve the reliability of power supply, it was relaborated a reformation and repowering project of the equipment using aramids, a special polymeric material. This paper describes the phases of the project, and presents the benefits obtained, and also the characteristics of the electric system of the production unit. (author)

  7. Amine-based post-combustion CO2 capture in air-blown IGCC systems with cold and hot gas clean-up

    International Nuclear Information System (INIS)

    Giuffrida, A.; Bonalumi, D.; Lozza, G.

    2013-01-01

    Highlights: • Hot fuel gas clean-up is a very favorable technology for IGCC concepts. • IGCC net efficiency reduces to 41.5% when realizing post-combustion CO 2 capture. • Complex IGCC layouts are necessary if exhaust gas recirculation is realized. • IGCC performance does not significantly vary with exhaust gas recirculation. - Abstract: This paper focuses on the thermodynamic performance of air-blown IGCC systems with post-combustion CO 2 capture by chemical absorption. Two IGCC technologies are investigated in order to evaluate two different strategies of coal-derived gas clean-up. After outlining the layouts of two power plants, the first with conventional cold gas clean-up and the second with hot gas clean-up, attention is paid to the CO 2 capture station and to issues related to exhaust gas recirculation in combined cycles. The results highlight that significant improvements in IGCC performance are possible if hot coal-derived gas clean-up is realized before the syngas fuels the combustion turbine, so the energy cost of CO 2 removal in an amine-based post-combustion mode is less strong. In particular, IGCC net efficiency as high as 41.5% is calculated, showing an interesting potential if compared to the one of IGCC systems with pre-combustion CO 2 capture. Thermodynamic effects of exhaust gas recirculation are investigated as well, even though IGCC performance does not significantly vary against a more complicated plant layout

  8. Efficiency enhancement in IGCC power plants with air-blown gasification and hot gas clean-up

    International Nuclear Information System (INIS)

    Giuffrida, Antonio; Romano, Matteo C.; Lozza, Giovanni

    2013-01-01

    Air-blown IGCC systems with hot fuel gas clean-up are investigated. In detail, the gas clean-up station consists of two reactors: in the first, the raw syngas exiting the gasifier and passed through high-temperature syngas coolers is desulfurized by means of a zinc oxide-based sorbent, whereas in the second the sulfided sorbent is duly regenerated. The hot fuel gas clean-up station releases H 2 S-free syngas, which is ready to fuel the combustion turbine after hot gas filtration, and a SO 2 -laden stream, which is successively treated in a wet scrubber. A thermodynamic analysis of two air-blown IGCC systems, the first with cold fuel gas clean-up and the second with hot fuel gas clean-up, both with a state-of-the-art combustion turbine as topping cycle, shows that it is possible to obtain a really attractive net efficiency (more than 51%) for the second system, with significant improvements in comparison with the first system. Nevertheless, higher efficiency is accomplished with a small reduction in the power output and no sensible efficiency improvements seem to be appreciated when the desulfurization temperature increases. Other IGCC systems, with an advanced 1500 °C-class combustion turbine as the result of technology improvements, are investigated as well, with efficiency as high as 53%. - Highlights: ► Hot fuel gas clean-up is a highly favorable technology for IGCC concepts. ► Significant IGCC efficiency improvements are possible with hot fuel gas clean-up. ► Size reductions of several IGCC components are possible. ► Higher desulfurization temperatures do not sensibly affect IGCC efficiency. ► IGCC efficiency as high as 53% is possible with a 1500°C-class combustion turbine

  9. IGCC and PFBC By-Products: Generation, Characteristics, and Management Practices

    Energy Technology Data Exchange (ETDEWEB)

    Pflughoeft-Hassett, D.F.

    1997-09-01

    The following report is a compilation of data on by-products/wastes from clean coal technologies, specifically integrated gasification combined cycle (IGCC) and pressurized fluidized-bed combustion (PFBC). DOE had two objectives in providing this information to EPA: (1) to familiarize EPA with the DOE CCT program, CCT by-products, and the associated efforts by DOE contractors in the area of CCT by-product management and (2) to provide information that will facilitate EPA's effort by complementing similar reports from industry groups, including CIBO (Council of Industrial Boiler Owners) and EEI USWAG (Edison Electric Institute Utility Solid Waste Activities Group). The EERC cooperated and coordinated with DOE CCT contractors and industry groups to provide the most accurate and complete data on IGCC and PFBC by-products, although these technologies are only now being demonstrated on the commercial scale through the DOE CCT program.

  10. Computer models and simulations of IGCC power plants with Canadian coals

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, L.; Furimsky, E.

    1999-07-01

    In this paper, three steady state computer models for simulation of IGCC power plants with Shell, Texaco and BGL (British Gas Lurgi) gasifiers will be presented. All models were based on a study by Bechtel for Nova Scotia Power Corporation. They were built by using Advanced System for Process Engineering (ASPEN) steady state simulation software together with Fortran programs developed in house. Each model was integrated from several sections which can be simulated independently, such as coal preparation, gasification, gas cooling, acid gas removing, sulfur recovery, gas turbine, heat recovery steam generation, and steam cycle. A general description of each process, model's overall structure, capability, testing results, and background reference will be given. The performance of some Canadian coals on these models will be discussed as well. The authors also built a computer model of IGCC power plant with Kellogg-Rust-Westinghouse gasifier, however, due to limitation of paper length, it is not presented here.

  11. The reliability of integrated gasification combined cycle (IGCC) power generation units

    Energy Technology Data Exchange (ETDEWEB)

    Higman, C.; DellaVilla, S.; Steele, B. [Syngas Consultants Ltd. (United Kingdom)

    2006-07-01

    This paper presents two interlinked projects aimed at supporting the improvement of integrated gasification combined cycle (IGCC) reliability. The one project comprises the extension of SPS's existing ORAP (Operational Reliability Analysis Program) reliability, availability and maintainability (RAM) tracking technology from its existing base in natural gas open and combined cycle operations into IGCC. The other project is using the extended ORAP database to evaluate performance data from existing plants. The initial work has concentrated on evaluating public domain data on the performance of gasification based power and chemical plants. This is being followed up by plant interviews in some 20 plants to verify and expand the database on current performance. 23 refs., 8 figs., 2 tabs.

  12. Development of advanced air-blown entrained-flow two-stage bituminous coal IGCC gasifier

    Directory of Open Access Journals (Sweden)

    Abaimov Nikolay A.

    2017-01-01

    Full Text Available Integrated gasification combined cycle (IGCC technology has two main advantages: high efficiency, and low levels of harmful emissions. Key element of IGCC is gasifier, which converts solid fuel into a combustible synthesis gas. One of the most promising gasifiers is air-blown entrained-flow two-stage bituminous coal gasifier developed by Mitsubishi Heavy Industries (MHI. The most obvious way to develop advanced gasifier is improvement of commercial-scale 1700 t/d MHI gasifier using the computational fluid dynamics (CFD method. Modernization of commercial-scale 1700 t/d MHI gasifier is made by changing the regime parameters in order to improve its cold gas efficiency (CGE and environmental performance, namely H2/CO ratio. The first change is supply of high temperature (900°C steam in gasifier second stage. And the second change is additional heating of blast air to 900°C.

  13. Dynamic simulation of a low-temperature rectification Column as part of an IGCC power plant

    Energy Technology Data Exchange (ETDEWEB)

    Hanke, R. [Leipzig University of Applied Sciences, Department of Mechanical and Energy Engineering, P.O. Box 300066, D-04251 Leipzig (Germany); Hannemann, F. [Siemens AG - Power Generation, PG CTET, P.O. Box 3220, D-91050 Erlangen (Germany); Sundmacher, K. [Max Planck Institute of Dynamics of Complex Technical Systems, Sandtorstrasse 1, D-39106 Magdeburg (Germany); Otto-von-Guericke University Magdeburg, Faculty of Process and Systems Engineering, P.O. Box 4120, D-39106 Magdeburg (Germany)

    2003-11-01

    IGCC plants offer the opportunity to utilize fossil energy sources, like coal or heavy refinery residues, to satisfy increasing energy demand while considering strict environmental constraints. Such a plant consists of a combined power cycle, a fuel gasifier with downstream fuel gas conditioning and an air separation unit (ASU), where the oxygen required for gasification is produced. The low-temperature rectification column as the core of the ASU strongly affects the transient behavior of the system. (Abstract Copyright [2003], Wiley Periodicals, Inc.)

  14. Novel findings about management of gastric cancer: A summary from 10th IGCC

    OpenAIRE

    Penon, Danila; Cito, Letizia; Giordano, Antonio

    2014-01-01

    The Tenth International Gastric Cancer Congress (IGCC) was held in Verona, Italy, from June 19 to 22, 2013. The meeting enclosed various aspects of stomach tumor management, including both tightly clinical approaches, and topics more related to basic research. Moreover, an overview on gastrointestinal stromal tumors was provided too, although here not discussed. Here we will discuss some topics related to molecular biology of gastric cancer (GC), inherent to prognostic, diagnostic and therape...

  15. The installation IGCC power plans in the petroleum refinement: international experiences and lessons for Mexico; La instalacion de plantas IGCC en la refinacion de petroleo: experiencias internacionales y lecciones para Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Hernandez, Joel [Ecole du Petrole et des Moteurs, Institut Franzais du Petrole, (France)

    2004-06-15

    In this work, are presented the technical and economic elements of the international experience for the installation of IGCC power plants in the petroleum refinement and the lessons for Mexico in the installation of this technology in PEMEX Refinacion are analyzed. The construction of IGCC power plants in the petroleum refinement has grown 14.3 % at worldwide level as of 1996, in which there was already an installed capacity of 160 MW. At the end of 2003 an installed capacity of 2,500 MW was reached. The growth in the installation of IGCC power plants fundamentally appears in Europe, being Italy and Spain leader countries in the construction of this technology in the petroleum refinement. However, countries like Holland, Japan, Singapore and the United States count on IGCC power plants for electricity and hydrogen generation, which take advantage of low value fuels such as vacuum tower residues, petroleum coke, asphalt, liquid fuels, among others. In Mexico, the installation IGCC power plants in the petroleum refinement is null, nevertheless Petroleos Mexicanos counts with the approval of the government for the installation of cogeneration power plants in its facilities. This approval would allow PEMEX to carry out projects for the installation IGCC power plants, specifically in PEMEX Refinacion, for the generation of electricity and hydrogen from the advantage of heavy residues of low economic value. The opportunity that the installation IGCC power plants in the petroleum refinement offers is directed towards the commercialization of the electricity and hydrogen, which would impel PEMEX Refinacion to enter the competition of the electrical market in Mexico. [Spanish] En este trabajo, se presentan los elementos tecnicos y economicos de la experiencia internacional para la instalacion de plantas IGCC en la refinacion de petroleo y se analizan las lecciones para Mexico en la instalacion de esta tecnologia en PEMEX Refinacion. La construccion de plantas IGCC en la

  16. Thermal expansion of slag and fly ash from coal gasification in IGCC power plant

    Energy Technology Data Exchange (ETDEWEB)

    M. Aineto; A. Acosta; J.M.A. Rincon; M. Romero [University of Castilla La Mancha, Ciudad Real (Spain). Laboratory of Applied Mineralogy

    2006-11-15

    Integrated gasification in combined cycle (IGCC) is an electrical power generation system which is characterized to be a clean coal technology different than conventional process in combustible treatment. IGCC process gives rise to inorganic solid wastes in the form of vitreous slag and fly ashes with singular thermal properties. The gasification of the fuel takes place at high temperature and pressure in reducing atmosphere. Under that conditions, gases such as H{sub 2}, N{sub 2} or CO, which are the main components of the gas mixture in the gasifier, show a high solubility in the melt and during the cooling remain enclosed in the vitreous slag. When these wastes are afterward thermal treated in oxidizing conditions, two phenomena occur. The development of a crystalline phase by devitrification of the glassy matrix and the releasing of the enclosed gas, which starts at temperatures nearly to the softening point. At higher temperatures the bubbles with increasing kinetic energy tend to ascend with difficulty through the viscous liquid phase and promotes an expansive reaction, giving rise to a foam glass-ceramic product. This paper has been focused on the study of thermal expansion in slag and fly ash samples from the ELCOGAS IGCC power plant located in Puertollano (Spain). 18 refs., 11 figs., 1 tab.

  17. Kotka ecopower IGCC-project, the attempt to transfer the biocycle project to Finland

    International Nuclear Information System (INIS)

    Salo, K.

    1998-01-01

    The Danish utilities Elsam and Elkraft planned to build a small (7 MW e ) IGCC-plant in Denmark, called Biocycle Project, based on the gasification and gas clean-up technology of Enviropower Inc. EU/THERMIE program committed to finance part of the investment. The project, however, was not feasible due to the difficulty of finding a suitable customer and sufficient amount of reasonably priced biomass. For this reason a new host and site was found for the Biocycle project. The new site was in Kotka, Finland, where Kotka Energy Ltd., the Energy Board of the City of Kotka acted as the main partner. The fuel of the IGCC project would have been sugar mill wood residue from Xyrofin Inc. During the feasibility investigation (project definition phase) Xyrofin Inc. made the decision to change the production process which eliminated the wood waste production. Without no-cost fuel and due to the low electricity price in Finland the small size IGCC power plant proved not to be feasible. (author)

  18. CO2 control technology effects on IGCC plant performance and cost

    International Nuclear Information System (INIS)

    Chen Chao; Rubin, Edward S.

    2009-01-01

    As part of the USDOE's Carbon Sequestration Program, an integrated modeling framework has been developed to evaluate the performance and cost of alternative carbon capture and storage (CCS) technologies for fossil-fueled power plants in the context of multi-pollutant control requirements. This paper uses the newly developed model of an integrated gasification combined cycle (IGCC) plant to analyze the effects of adding CCS to an IGCC system employing a GE quench gasifier with water gas shift reactors and a Selexol system for CO 2 capture. Parameters of interest include the effects on plant performance and cost of varying the CO 2 removal efficiency, the quality and cost of coal, and selected other factors affecting overall plant performance and cost. The stochastic simulation capability of the model is also used to illustrate the effect of uncertainties or variability in key process and cost parameters. The potential for advanced oxygen production and gas turbine technologies to reduce the cost and environmental impacts of IGCC with CCS is also analyzed

  19. From troubled kid to star performers - On the repowering of a biogas plant; Vom Sorgenkind zum Musterknaben. Ueber das Repowering einer Biogasanlage

    Energy Technology Data Exchange (ETDEWEB)

    Gress, Hans-Werner [ABO Wind AG, Wiesbaden (Germany)

    2011-07-01

    In 2001, the biogas plant in Samswegen (Federal Republic of Germany) has been successfully inaugurated. The plant proposed by Schmack AG (Schwandorf, Federal Republic of Germany) consisted of two horizontal plug flow digesters and three storage-flow digesters. Due to incidents this concept was not feasible in practical operation. Under this aspect, the author of the contribution under consideration reports on the repowering of a biogas plant. This includes a retrofit with necessary components such as a gas torch, a gas cooler and external desulfurization. Similarly, the solids metering was renewed. The recirculation could be reduced by 80 %.

  20. Environmental considerations of coal gasification technology and the Wabash River Repowering Project

    International Nuclear Information System (INIS)

    Lessig, W.S.; Frederick, J.D.

    1993-01-01

    The Clean Air Act Amendments of 1990 have mandated a significant reduction in sulfur dioxide emissions. Coal gasification can assist coal burning utilities in meeting this challenge. The use of combustion turbines in the cycle is an important factor in terms of efficiency and pollution control technologies. The gasification process can be utilized in several applications including 'repowering' existing coal-fired facilities as well as new 'greenfield' projects. This paper addresses the environmental benefits of the repowering application at PSI Energy's Wabash River Station. The environmental impacts of air, water, solid waste, trace hazardous air pollutants, and fuel sources are addressed. Specifically, sulfur removal is discussed on both a technical and an economic level

  1. AC transmission network expansion planning considering circuits repowering and location of capacitors

    OpenAIRE

    Jaime A. López-López; Diego A. Tejada-Arango; Jesús M. López-Lezama

    2016-01-01

    This paper deals with the Transmission Network Expansion Planning (TNEP) problem. The TNEP consists of finding a set of new circuits on a power system, which is needed to attend a future demand. In its classical version, the TNEP only considers as solution candidates the addition of new lines and transformers. The main contribution of this paper consists in the inclusion of nonconventional solution candidates, namely the repowering of existing circuits and the location of capacitor banks. To ...

  2. Technical considerations in repowering a nuclear plant for fossil fueled operation

    International Nuclear Information System (INIS)

    Patti, F.J.

    1996-01-01

    Repowering involves replacement of the reactor by a fossil fuel source of steam. This source can be a conventional fossil fueled boiler or the heat recovery steam generator (HRSG) on a gas turbine exhaust. The existing steam turbine plant is used to the extent possible. Alternative fuels for repowering a nuclear plant are coal, natural gas and oil. In today's world oil is not usually an alternative. Selection of coal or natural gas is largely a matter of availability of the fuel near the location of the plant. Both the fossil boiler and the HRSG produce steam at higher pressures and temperatures than the throttle conditions for a saturated steam nuclear turbine. It is necessary to match the steam conditions from the new source to the existing turbine as closely as possible. Technical approaches to achieve a match range from using a topping turbine at the front end of the cycle to attemperation of the throttle steam with feedwater. The electrical output from the repowered plant is usually greater than that of the original nuclear fueled design. This requires consideration of the ability to use the excess electricity. Interfacing of the new facility with the existing turbine plant requires consideration of facility layout and design. Site factors must also be considered, especially for a coal fired boiler, since rail and coal handling facilities must be added to a site for which these were not considered. Additional site factors that require consideration are ash handling and disposal

  3. Newman Unit 1 advanced solar repowering advanced conceptual design. Final report

    Energy Technology Data Exchange (ETDEWEB)

    None

    1982-04-01

    The Newman Unit 1 solar repowering design is a water/steam central receiver concept supplying superheated steam. The work reported is to develop a refined baseline conceptual design that has potential for construction and operation by 1986, makes use of existing solar thermal technology, and provides the best economics for this application. Trade studies performed in the design effort are described, both for the conceptual design of the overall system and for the subsystem conceptual design. System-level functional requirements, design, operation, performance, cost, safety, environmental, institutional, and regulatory considerations are described. Subsystems described include the collector, receiver, fossil energy, electrical power generating, and master control subsystems, site and site facilities. The conceptual design, cost, and performance of each subsystem is discussed at length. A detailed economic analysis of the repowered unit is made to realistically assess the economics of the first repowered unit using present cost data for a limited production level for solar hardware. Finally, a development plan is given, including the design, procurement, construction, checkout, startup, performance validation, and commercial operation. (LEW)

  4. Vojany Station reconstruction, repowering and expansion assessment: Options, issues and opportunities

    Energy Technology Data Exchange (ETDEWEB)

    Coe, W.F. [Southern Electric International, Inc., Atlanta, GA (United States); Griswold, G.H.; Peyton, J.C. [Southern Company Services, Inc., Birmingham, AL (United States)

    1995-12-01

    Recent European community and state specific environmental guideline, legislative, and regulatory activities have led power producers to assess their currently installed generation technologies with regard to clean air compliance strategies. For the application to older generation facilities, the prudence of linking facility rehabilitation with the addition of environmental control systems to repowering options is warranted. Similarly, ongoing privatization efforts emphasize the necessity for sound economic decisions of site specific technological applications that consider maintaining or enhancing thermal efficiencies. Southern Electric International (SEI) has conducted such a feasibility study assessment evaluating the reconstruction, repowering and possible expansion of the Slovensky Energeticky Podnik (SEP) 1320 MWe Vojany Station in the Republic of Slovakia. Alternatives included such technologies as atmospheric fluid bed combustion, furnace and duct sorbent injection, low NOx burners, gas re-burn, selective catalytic reduction, selective non-catalytic reduction, state of the art precipitators and baghouses, wet and dry flue gas desulfurization systems and repowering technologies. In addition, new, turn of the century environmentally plausible and efficient electric power technologies were addressed.

  5. Comprehensive report to Congress Clean Coal Technology Program

    Energy Technology Data Exchange (ETDEWEB)

    1990-10-01

    This project will demonstrate Integrated Gasification Combined Cycle (IGCC) technology in a commercial application by the repowering of an existing City Water, Light and Power (CWL P) Plant in Springfield, Illinois. The project duration will be 126 months, including a 63-month demonstration period. The estimated cost of the project is $270,700,000 of which $129,357,204 will be funded by DOE. The IGCC system will consist of CE's air-blown, entrained-flow, two-stage, pressurized coal gasifier; an advanced hot gas cleanup process; a combustion turbine modified to use low Btu coal gas; and all necessary coal handling equipment. An existing 25-MWe steam turbine and associated equipment will also be part of the IGCC system. The result of repowering will be an IGCC power plant with low environmental emissions and high net plant efficiency. The repowering will increase plant output by 40 MWe through addition of the combustion turbine, thus providing a total IGCC capacity of a nominal 65 MWe. 3 figs., 2 tabs.

  6. Shell coal IGCCS with carbon capture: Conventional gas quench vs. innovative configurations

    International Nuclear Information System (INIS)

    Martelli, Emanuele; Kreutz, Thomas; Carbo, Michiel; Consonni, Stefano; Jansen, Daniel

    2011-01-01

    Highlights: → We aim at defining the preferred IGCC design for dry feed gasifiers with CO 2 capture. → Multiple options of syngas cooling, humidification, and WGS are considered. → Plants are designed, modeled, numerically optimized and costs are carefully assessed. → Partial water quench has poor efficiency but low capital cost, then good performance. → Gas quench with the ECN staged WGS design has the best thermo-economic performance. -- Abstract: The Shell coal integrated gasification combined cycle (IGCC) based on the gas quench system is one of the most fuel flexible and energy efficient gasification processes because is dry feed and employs high temperature syngas coolers capable of rising high pressure steam. Indeed the efficiency of a Shell IGCC with the best available technologies is calculated to be 47-48%. However the system looses many percentage points of efficiency (up to 10) when introducing carbon capture. To overcome this penalty, two approaches have been proposed. In the first, the expensive syngas coolers are replaced by a 'partial water quench' where the raw syngas stream is cooled and humidified via direct injection of hot water. This design is less costly, but also less efficient. The second approach retains syngas coolers but instead employs novel water-gas shift (WGS) configurations that requires substantially less steam to obtain the same degree of CO conversion to CO 2 , and thus increases the overall plant efficiency. We simulate and optimize these novel configurations, provide a detailed thermodynamic and economic analysis and investigate how these innovations alter the plant's efficiency, cost and complexity.

  7. The role of IGCC technology in power generation using low-rank coal

    Energy Technology Data Exchange (ETDEWEB)

    Juangjandee, Pipat

    2010-09-15

    Based on basic test results on the gasification rate of Mae Moh lignite coal. It was found that an IDGCC power plant is the most suitable for Mae Moh lignite. In conclusion, the future of an IDGCC power plant using low-rank coal in Mae Moh mine would hinge on the strictness of future air pollution control regulations including green-house gas emission and the constraint of Thailand's foreign currency reserves needed to import fuels, in addition to economic consideration. If and when it is necessary to overcome these obstacles, IGCC is one variable alternative power generation must consider.

  8. Effective utilization of fossil fuels for low carbon world -- IGCC and high performance gas turbine

    Energy Technology Data Exchange (ETDEWEB)

    Ishii, Hiromi; Hashimoto, Takao; Sakamoto, Koichi; Komori, Toyoaki; Kishine, Takashi; Shiozaki, Shigehiro

    2010-09-15

    The reduction of greenhouse-gas emissions is required to minimize the effect of hydrocarbon based power generation on global warming. In pursue of this objective, Mitsubishi Heavy Industries is dedicating considerable efforts on two different ways to reduce the environmental impact. The first one involves gas turbine performance improvement by raising firing temperature for Natural-gas and LNG applications. In this regard, the latest J class gas turbine was designed to operate at 1600 deg C and expected combined cycle efficiency in excess of 60%. The other approach involves the use of Integrated Gasification Combined Cycle (IGCC) plants to burn solid fuel like coal.

  9. Fiscal 1999 basic survey report for promotion of joint implementation. Plan for repowering Ashuganji thermal power station; 1999 nendo Ashuganji karyoku hatsudensho no repowering keikaku chosa hokokusho

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-03-01

    A study is conducted of a plan to repower the Ashuganji thermal power station, the People's Republic of Bangladesh, with the plan to be connected to the clean development mechanism (CDM). For conversion of the existing No. 3, No. 4, and No. 5 generators (each outputting 150MW) into full fired heat recovery combined cycle generators, 31MW gas turbines are added, one to each of the three. The construction cost is calculated to be 14,000-million yen. Fuel (natural gas) will be saved by 28kt/year/generator, the three saving 2.1-million tons in total in 25 years. There will be a CO2 reduction of 77kt/year/generator, the total reduction to be 5.8-million tons in 25 years for the three generators. Then payback is assessed. In the main case (with the repowering-created increase in output to be used to cover the current power supply shortage), where the internal rate of return of 8.09% is much lower than the discount rate of 15.5% during the 10-year period for payback in case of financing by private funds, the discounted present worth is predicted to be negative and then the project is not feasible. Since there will be no problems about the repayment of borrowed money, however, it is hoped that low-interest special yen credit will be granted for the elimination of chronic power shortage. When it comes to international emission trading (550 yen/ton of CO2), payback is again found to be impossible. (NEDO)

  10. Analysis of Renewable Energy Policies Related to Repowering the Wind Energy Sector: the Spanish Case

    OpenAIRE

    Rodriguez, Roberto; Rodríguez Monroy, Carlos; Rodriguez, Rubén; Calvo Narvaez, Felix

    2013-01-01

    In countries that started early with wind energy, the old wind turbines were located in places where the wind is often very good. Since the best places in which the wind is concerned are occupied by old wind turbines (with lower capacity than the more recent ones) the trend is to start replacing old turbines with new ones. With repowering, the first generation of wind turbines can be replaced by modern multi-megawatt wind turbines. The aim of this article is to analyze energy policies in ...

  11. Shell coal IGCCS with carbon capture. Conventional gas quench vs. innovative configurations

    Energy Technology Data Exchange (ETDEWEB)

    Martellia, E.; Consonni, S. [Politecnico di Milano, Via Scalabrini 76, Piacenza (Italy); Kreutz, T. [Princeton University, Guyot Hall, Room 129, Princeton, NJ (United States); Carbo, M.; Jansen, D. [Energy research Centre of the Netherlands ECN, P.O. Box 1, 1755 ZG, Petten (Netherlands)

    2011-11-15

    The Shell coal integrated gasification combined cycle (IGCC) based on the gas quench system is one of the most fuel flexible and energy efficient gasification processes because is dry feed and employs high temperature syngas coolers capable of rising high pressure steam. Indeed the efficiency of a Shell IGCC with the best available technologies is calculated to be 47-48%. However the system looses many percentage points of efficiency (up to 10) when introducing carbon capture. To overcome this penalty, two approaches have been proposed. In the first, the expensive syngas coolers are replaced by a 'partial water quench' where the raw syngas stream is cooled and humidified via direct injection of hot water. This design is less costly, but also less efficient. The second approach retains syngas coolers but instead employs novel water-gas shift (WGS) configurations that requires substantially less steam to obtain the same degree of CO conversion to CO2, and thus increases the overall plant efficiency. We simulate and optimize these novel configurations, provide a detailed thermodynamic and economic analysis and investigate how these innovations alter the plant's efficiency, cost and complexity.

  12. A single IGCC design for variable CO{sub 2} capture

    Energy Technology Data Exchange (ETDEWEB)

    O' Keefe, L.F.; Griffiths, J.; Wainwright, J.M. [Chevron Texaco Worldwide Power and Gasification, Houston, TX (United States)

    2002-07-01

    Global warming and the production of greenhouse gases (GHG) have become an important issue in many countries around the world. While there has been a heightened sense of awareness that the combustion of fossil fuels produces the majority of the controllable carbon dioxide released to the atmosphere, there have been few substantive solutions that produce economically realistic solutions. Moreover, some fossil fuels, like coal, are viewed negatively due to their relatively high carbon content per Btu. Integrated Gasification Combined Cycle (IGCC) offers the option of a realistic, economically viable solution for reducing, by pre-combustion capture, significant amounts of CO{sub 2} while using existing commercially proven technologies. The novel IGCC flowscheme is designed so that the power plant can be built and operated without CO{sub 2} removal and later upgraded to low CO{sub 2} emissions at minimal additional cost. The novel flowscheme is based on commercially proven technology using processes that are in operation today. Overall performance and capital cost estimates are presented and two other possible applications of the novel flowscheme are discussed in this paper. 17 refs., 3 figs., 2 tabs.

  13. Conceptual model and evaluation of generated power and emissions in an IGCC plant

    International Nuclear Information System (INIS)

    Perez-Fortes, M.; Bojarski, A.D.; Velo, E.; Nougues, J.M.; Puigjaner, L.

    2009-01-01

    This work develops a design and operation support tool for an Integrated Gasification Combined Cycle (IGCC) power plant, which allows the efficiency and environmental issues of alternative process designs and feedstock to be assessed. The study is based on a conceptual model of an IGCC plant, validated with data from the ELCOGAS power plant in Spain. The layout of the model includes an Air Separation Unit (ASU), a Pressurized Entrained Flow (PRENFLO) gasifier, a series of purification gas units (venturi scrubber, sour water steam stripper, COS hydrolysis reactor, MDEA absorber columns and a sulphur recovery Claus plant), a Heat Recovery Steam Generator (HRSG) and a Combined Cycle (CC) system. It comprises steady state models. One of the purposes of this work is to analyze the feasibility of coal co-gasification using waste materials; specifically petcoke and olive pomace (orujillo) are considered here. The model has been developed in Aspen Hysys. It uses electrolyte models that have been implemented in Aspen Plus which are connected to Aspen Hysys by means of Artificial Neural Networks (ANNs) models. Results of the model's, gas composition and generated power, are in agreement with the industrial data.

  14. More Energy-Efficient CO2 Capture from IGCC GE Flue Gases

    Directory of Open Access Journals (Sweden)

    Rakpong Peampermpool

    2017-03-01

    Full Text Available Carbon dioxide (CO2 emissions are one of the main reasons for the increase in greenhouse gasses in the earth’s atmosphere and carbon capture and sequestration (CCS is known as an effective method to reduce CO2 emissions on a larger scale, such as for fossil energy utilization systems. In this paper, the feasibility of capturing CO2 using cryogenic liquefaction and improving the capture rate by expansion will be discussed. The main aim was to design an energy-saving scheme for an IGCC (integrated gasification combined cycle power plant with CO2 cryogenic liquefaction capture. The experimental results provided by the authors, using the feed gas specification of a 740 MW IGCC General Electric (GE combustion power plant, demonstrated that using an orifice for further expanding the vent gas after cryogenic capture from 57 bar to 24 bar gave an experimentally observed capture rate up to 65%. The energy-saving scheme can improve the overall CO2 capture rate, and hence save energy. The capture process has also been simulated using Aspen HYSYS simulation software to evaluate its energy penalty. The results show that a 92% overall capture rate can be achieved by using an orifice.

  15. Conceptual model and evaluation of generated power and emissions in an IGCC plant

    Energy Technology Data Exchange (ETDEWEB)

    Perez-Fortes, M.; Bojarski, A. D.; Velo, E.; Nougues, J. M. [Department of Chemical Engineering, Universitat Politecnica de Catalunya, ETSEIB, Avda. Diagonal, 647, E-08028 Barcelona (Spain); Puigjaner, L., E-mail: luis.puigjaner@upc.edu [Department of Chemical Engineering, Universitat Politecnica de Catalunya, ETSEIB, Avda. Diagonal, 647, E-08028 Barcelona (Spain)

    2009-10-15

    This work develops a design and operation support tool for an Integrated Gasification Combined Cycle (IGCC) power plant, which allows the efficiency and environmental issues of alternative process designs and feedstock to be assessed. The study is based on a conceptual model of an IGCC plant, validated with data from the ELCOGAS power plant in Spain. The layout of the model includes an Air Separation Unit (ASU), a Pressurized Entrained Flow (PRENFLO) gasifier, a series of purification gas units (venturi scrubber, sour water steam stripper, COS hydrolysis reactor, MDEA absorber columns and a sulphur recovery Claus plant), a Heat Recovery Steam Generator (HRSG) and a Combined Cycle (CC) system. It comprises steady state models. One of the purposes of this work is to analyze the feasibility of coal co-gasification using waste materials; specifically petcoke and olive pomace (orujillo) are considered here. The model has been developed in Aspen Hysys. It uses electrolyte models that have been implemented in Aspen Plus which are connected to Aspen Hysys by means of Artificial Neural Networks (ANNs) models. Results of the model's, gas composition and generated power, are in agreement with the industrial data.

  16. Conceptual model and evaluation of generated power and emissions in an IGCC plant

    Energy Technology Data Exchange (ETDEWEB)

    Perez-Fortes, M; Bojarski, A D; Velo, E; Nougues, J M; Puigjaner, L [Department of Chemical Engineering, Universitat Politecnica de Catalunya, ETSEIB, Avda. Diagonal, 647, E-08028 Barcelona (Spain)

    2009-10-15

    This work develops a design and operation support tool for an Integrated Gasification Combined Cycle (IGCC) power plant, which allows the efficiency and environmental issues of alternative process designs and feedstock to be assessed. The study is based on a conceptual model of an IGCC plant, validated with data from the ELCOGAS power plant in Spain. The layout of the model includes an Air Separation Unit (ASU), a Pressurized Entrained Flow (PRENFLO) gasifier, a series of purification gas units (venturi scrubber, sour water steam stripper, COS hydrolysis reactor, MDEA absorber columns and a sulphur recovery Claus plant), a Heat Recovery Steam Generator (HRSG) and a Combined Cycle (CC) system. It comprises steady state models. One of the purposes of this work is to analyze the feasibility of coal co-gasification using waste materials; specifically petcoke and olive pomace (orujillo) are considered here. The model has been developed in Aspen Hysys. It uses electrolyte models that have been implemented in Aspen Plus which are connected to Aspen Hysys by means of Artificial Neural Networks (ANNs) models. Results of the model's, gas composition and generated power, are in agreement with the industrial data. (author)

  17. Conceptual model and evaluation of generated power and emissions in an IGCC plant

    Energy Technology Data Exchange (ETDEWEB)

    Perez-Fortes, M.; Bojarski, A.D.; Velo, E.; Nougues, J.M.; Puigjaner, L. [Department of Chemical Engineering, Universitat Politecnica de Catalunya, ETSEIB, Avda. Diagonal, 647, E-08028 Barcelona (Spain)

    2009-10-15

    This work develops a design and operation support tool for an Integrated Gasification Combined Cycle (IGCC) power plant, which allows the efficiency and environmental issues of alternative process designs and feedstock to be assessed. The study is based on a conceptual model of an IGCC plant, validated with data from the ELCOGAS power plant in Spain. The layout of the model includes an Air Separation Unit (ASU), a Pressurized Entrained Flow (PRENFLO) gasifier, a series of purification gas units (venturi scrubber, sour water steam stripper, COS hydrolysis reactor, MDEA absorber columns and a sulphur recovery Claus plant), a Heat Recovery Steam Generator (HRSG) and a Combined Cycle (CC) system. It comprises steady state models. One of the purposes of this work is to analyze the feasibility of coal co-gasification using waste materials; specifically petcoke and olive pomace (orujillo) are considered here. The model has been developed in Aspen Hysys. It uses electrolyte models that have been implemented in Aspen Plus which are connected to Aspen Hysys by means of Artificial Neural Networks (ANNs) models. Results of the model's, gas composition and generated power, are in agreement with the industrial data. (author)

  18. Integration optimisation of elevated pressure air separation unit with gas turbine in an IGCC power plant

    International Nuclear Information System (INIS)

    Han, Long; Deng, Guangyi; Li, Zheng; Wang, Qinhui; Ileleji, Klein E.

    2017-01-01

    Highlights: • IGCC thermodynamic model was setup carefully. • Simulations focus on integration between an elevated pressure ASU with gas turbine. • Different recommended solutions from those of low pressure ASUs are figured out. • Full N 2 injection and 80% air extraction was suggested as the optimum integration. - Abstract: The integration optimisation between an elevated pressure air separation unit (EP-ASU) and gas turbine is beneficial to promote net efficiency of an integrated gasification combined cycle (IGCC) power plant. This study sets up the thermodynamic model for a 400 MW plant specially coupled with an EP-ASU, aiming to examine system performances under different integrations and acquire the optimum solution. Influences of air extraction rate at conditions of without, partial and full N 2 injection, as well as the effects of N 2 injection rate when adopting separate ASU, partial and full integrated ASU were both analysed. Special attention has been paid to performance differences between utilising an EP-ASU and a low pressure unit. Results indicated that integration solution with a separate EP-ASU or without N 2 injection would not be reasonable. Among various recommended solutions for different integration conditions, N 2 injection rate increased with the growth of air extraction rate. The integration with an air extraction rate of 80% and full N 2 injection was suggested as the optimum solution. It is concluded that the optimum integration solution when adopting an EP-ASU is different from that using a low pressure one.

  19. Novel findings about management of gastric cancer: a summary from 10th IGCC.

    Science.gov (United States)

    Penon, Danila; Cito, Letizia; Giordano, Antonio

    2014-07-21

    The Tenth International Gastric Cancer Congress (IGCC) was held in Verona, Italy, from June 19 to 22, 2013. The meeting enclosed various aspects of stomach tumor management, including both tightly clinical approaches, and topics more related to basic research. Moreover, an overview on gastrointestinal stromal tumors was provided too, although here not discussed. Here we will discuss some topics related to molecular biology of gastric cancer (GC), inherent to prognostic, diagnostic and therapeutic tools shown at the conference. Results about well known subjects, such as E-cadherin loss of expression/function, were presented. They revealed that other mutations of the gene were identified, showing a continuous research to improve diagnosis and prognosis of stomach tumor. Simultaneously, new possible molecular markers with an established role for other neoplasms, were discussed, such as mesothelin, stomatin-like protein 2 and Notch-1. Hence, a wide overview including both old and new diagnostic/prognostic tools was offered. Great attention was also dedicated to possible drugs to be used against GC. They included monoclonal antibodies, such as MS57-2.1, drugs used in other pathologies, such as maraviroc, and natural extracts from plants such as biflorin. We would like to contribute to summarize the most impressive studies presented at the IGCC, concerning novel findings about molecular biology of gastric cancer. Although further investigations will be necessary, it can be inferred that more and more tools were developed, so as to better face stomach neoplasms.

  20. Towards retrofitting integrated gasification combined cycle (IGCC) power plants with solid oxide fuel cells (SOFC) and CO

    NARCIS (Netherlands)

    Thallam Thattai, A.; Oldenbroek, V.D.W.M.; Schoenmakers, L; Woudstra, T.; Purushothaman Vellayani, A.

    2017-01-01

    This article presents a detailed thermodynamic case study based on the Willem-Alexander Centrale (WAC) power plant in the Netherlands towards retrofitting SOFCs in existing IGCC power plants with a focus on near future implementation. Two systems with high percentage (up to 70%) biomass

  1. Water-gas shift (WGS) Operation of Pre-combustion CO2 Capture Pilot Plant at the Buggenum IGCC

    NARCIS (Netherlands)

    Van Dijk, H.A.J.; Damen, K.; Makkee, M.; Trapp, C.

    2014-01-01

    In the Nuon/Vattenfall CO2 Catch-up project, a pre-combustion CO2 capture pilot plant was built and operated at the Buggenum IGCC power plant, the Netherlands. The pilot consist of sweet water-gas shift, physical CO2 absorption and CO2 compression. The technology performance was verified and

  2. Propulsive machinery selection for repowering of an old patrol craft - A case study

    Science.gov (United States)

    Rahman, M. Muzibur; Mridha, A. H. Yusuf; Ahsan, Kazi Sakib

    2017-12-01

    This paper presents a case study of repowering peculiarities in relation to an old vessel. The vessel selected for study was designed for cruising speed of 15 knots. Over the years of operation the vessel's cruising speed reduced to about 8 knots. So, the owner wanted to repower it to have a fresh tenure of life and the work was given to a shipyard. But after replacement of old two engines by new engines of same power with different model, the performance of the vessel was not satisfactory. In the present paper, the problem is studied with comprehensive calculations of hydrostatic particulars and resistance of the ship. The analysis is carried out in respect of engine specifications, gear ratios, propeller design etc. and found that the operating ranges of new engines are not at par with the old engines. The new engine does not also match with old propeller. At this situation, comparative studies have determined that among all possible solutions redesign of propeller is the most suitable one and cost effective.

  3. Incorporating IGCC and CaO sorption-enhanced process for power generation with CO2 capture

    International Nuclear Information System (INIS)

    Chen, Shiyi; Xiang, Wenguo; Wang, Dong; Xue, Zhipeng

    2012-01-01

    Highlights: ► CaO sorption-enhanced process is incorporated with IGCC for CO 2 capture. ► IGCC–CCS is simplified using CaO sorption-enhanced process. ► The electricity efficiency is around 31–33% and CO 2 capture efficiency exceeds 95%. ► Parameters such as sorption pressure influence the system performance. -- Abstract: Integrated gasification combined cycle (IGCC) is a power generation technology to convert solid fuels into electricity. IGCC with CCS is regarded as a promising option to mitigate CO 2 emission. In this paper, the CaO sorption-enhanced process is incorporated downstream with coal gasification to produce a hydrogen-rich stream for electricity production and CO 2 separation. A WGS-absorber substitutes the high- and low-temperature water–gas shift reactors and desulfurization units in conventional IGCC–CCS to produce a hydrogen-rich stream, which is sent onto a gas turbine. CaO is used as the sorbent to enhance hydrogen production and for CO 2 capture. Regeneration of CaO is completed via calcination in a regenerator vessel. The IGCC with CaO sorption-enhanced process is modeled and simulated using Aspen Plus software. Two commercial available gasification technologies, Shell and Texaco, are integrated with the sorption-enhanced process. The results showed IGCC with CaO sorption-enhanced process has a satisfactory system performance. Even though the net electricity efficiency is not as high as expected, just around 30–33%, the system has a high CO 2 capture efficiency ∼97% and low pollutant emissions. Moreover, compared with conventional IGCC–CCS, the schematic diagram of the IGCC–CCS process is simplified. Parameters that affect the plant performance are analyzed in the sensitive analysis, including WGS-absorber temperature, H 2 O/CO ratio, pressure, etc. Some challenges to the system are also discussed.

  4. Method and system to estimate variables in an integrated gasification combined cycle (IGCC) plant

    Science.gov (United States)

    Kumar, Aditya; Shi, Ruijie; Dokucu, Mustafa

    2013-09-17

    System and method to estimate variables in an integrated gasification combined cycle (IGCC) plant are provided. The system includes a sensor suite to measure respective plant input and output variables. An extended Kalman filter (EKF) receives sensed plant input variables and includes a dynamic model to generate a plurality of plant state estimates and a covariance matrix for the state estimates. A preemptive-constraining processor is configured to preemptively constrain the state estimates and covariance matrix to be free of constraint violations. A measurement-correction processor may be configured to correct constrained state estimates and a constrained covariance matrix based on processing of sensed plant output variables. The measurement-correction processor is coupled to update the dynamic model with corrected state estimates and a corrected covariance matrix. The updated dynamic model may be configured to estimate values for at least one plant variable not originally sensed by the sensor suite.

  5. Speciation of major and selected trace elements in IGCC fly ash

    Energy Technology Data Exchange (ETDEWEB)

    Oriol Font; Xavier Querol; Frank E. Huggins; Jose M. Chimenos; Ana I. Fernandez; Silvia Burgos; Francisco Garcia Pena [Institute of Earth Sciences ' Jaume Almera' , Barcelona (Spain)

    2005-08-01

    The speciation of Ga, Ge, Ni, V, S and Fe in fly ash from IGCC power plant were investigated for possible further extraction process by combining conventional mineral and chemical analysis, leaching tests, wet sequential extraction, Moessbauer and XAFS spectroscopies. The results shown that Ge occurs mainly as water-soluble species, GeS and/or GeS{sub 2} and hexagonal GeO{sub 2}. Ga is present as an oxide, Ni occurs mainly as nickeline (NiAs), with minor proportions of Ni arsenates and vanadium as V(III) with minor amounts of V(IV) in the aluminosilicate glass matrix. Pyrrhotite and wurtzite-sphalerite are sulfide species containing Fe and Zn, but an important fraction of iron is also present in the aluminosilicate glass. These clear differences between the speciation of the above elements in this material and those reported for fly ash from conventional PC combustion. 15 refs., 8 figs., 5 tabs.

  6. Pushing forward IGCC and CO{sub 2}-free power plant technology at Siemens

    Energy Technology Data Exchange (ETDEWEB)

    Hannemann, E.; Vortmeyer, N.; Zimmermann, G. [Siemens AG, Erlangen (Germany). Power Generation

    2004-07-01

    Siemens Power Generation has entered into several R & D projects within the European Commissions' 5th and 6th Framework Programs. One objective of those projects is to develop advanced modular IGCC concepts for in-refinery energy and hydrogen supply. Additional projects are dealing with pre- and post-combustion decarbonisation technologies, which should achieve high carbon dioxide capture at low costs. In parallel, the development of advanced combustion systems including enhanced fuel flexibility and application of low BTU gases in the highly efficient Siemens V94.3A gas turbine are in progress. In further step the technology for burning hydrogen enriched gases resulting from decarbonisation in CO{sub 2} free power plants will be provided. This report documents the current status of these activities. 9 refs., 12 figs.

  7. Siemens sees a future for IGCC - and now it has the technology

    Energy Technology Data Exchange (ETDEWEB)

    Schmid, C.; Hannemann, F. [Siemens Fuel Gasification Technology, Freiberg (Germany)

    2007-10-15

    About 18 months ago Siemens became a key player in the gasification business through its acquisition of Freiberg based Future Energy and its GSP entrained flow technology, now called SFG (Siemens Fuel Gasification). Developed at Schwarze Pumpe in Eastern Germany over many years, a particular attraction of the process is its ability to use low rank fuels such as lignite, with a robust gasifier wall concept a 'cooling screen' that avoids the use of troublesome refractories. The article explains the SFG gasifier technology. It is ideally suited for coal-fueled IGCC power plants with integrated CO{sub 2} capture, especially for low-rank fuels. SFG has been ordered or pre-selected for a number of projects in China, North America and elsewhere. 5 figs.

  8. Thermodynamic assessment of IGCC power plants with hot fuel gas desulfurization

    International Nuclear Information System (INIS)

    Giuffrida, Antonio; Romano, Matteo C.; Lozza, Giovanni G.

    2010-01-01

    In IGCC power plants, hot gas desulfurization (HGD) represents an attractive solution to simplify syngas treatments and to improve the efficiency, potentially reducing the final cost of electricity. In the present study, the various consequences of the introduction of a HGD station in the power plant are discussed and evaluated, in comparison with conventional near-ambient temperature clean-up. Attention is paid to the potential improvements of the overall energy balance of the complete power station, along with the requirements of the sorbent regeneration process, to the influence of the desulfurization temperature and to the different solutions needed to control the NO x emissions (altered by the presence of HGD). The net performance of complete IGCC power plants (with HGD or with conventional desulfurization) were predicted, with reference to status-of-the-art solutions based on an entrained flow, dry-feed, oxygen-blown gasifier and on an advanced, FB-class combined cycle. The net efficiency experiences about 2.5% point improvement with HGD, even if a small reduction in the power output was predicted, when using the same combustion turbine. An exhaustive sensitivity analysis was carried out to evaluate the effects of different working conditions at the HGD station, e.g. desulfurization temperature and oxygen content in the gaseous stream for sorbent regeneration. According to the obtained results, these parameters have a weak influence on the efficiency. In particular, a very elevated desulfurization temperature (above 400-500 o C) does not provide decisive thermodynamic advantages. Therefore, the HGD unit optimization can be driven by technical and economical aspects and by emission abatement requirements. For instance, utilization of nitrogen for HGD sorbent regeneration (rather than for syngas dilution) and higher fuel temperature may improve the NO formation. Hence, different strategies to achieve acceptable NO x emissions (e.g. steam dilution) and their

  9. Corrosion of ceramics for slag removal in IGCC-power plants; Korrosion von Keramiken fuer die Fluessigascheabscheidung in IGCC-Kraftwerken

    Energy Technology Data Exchange (ETDEWEB)

    Fuerst, Denny

    2012-06-12

    Coal gasification and the subsequent production of electricity from syngas in combined-cycle powerplants allows plant efficiencies of up to 43% (LHV). Existing technologies allow up to 50% in the short term. Efficiencies beyond 50% however, require concepts and technologies that still need a certain amount of research and development. One such method to raise plant efficiencies would be a high temperature (at temperatures above the melting point of the ash) syngas cleaning. To effectively utilize the heat from the syngas and enable high turbine inlet temperatures, it is necessary to remove slag particles from the hot gas. The feasibility of such a hot syngas cleaning has been successfully demonstrated for the Pressurized Pulverized Coal Combustion (PPCC) by passing the hot gas through a bed of ceramic balls for slag removal. In order to apply this concept to IGCC powerplants the slag resistance of various ceramic materials had to be investigated under gasifying conditions. Therefore, lab-made ceramics and commercially available refractory materials where treated with liquid slag at 1600 C in a number of reducing atmospheres. At first, three synthetic slags with different basicity were used and after evaluating the results, selected materials were treated with a gasifier slag under continuous conditions. It was shown that both slag and ceramic have to be adjusted to ensure a sufficient corrosion resistance of the ceramic bed for slag removal. Furthermore, the impact of the porosity of the utilized ceramic on the corrosion resistance was shown. The composition of the reducing atmosphere (mainly the partial pressure of Oxygen) affected both physical and chemical properties of the slag via slag components that could easily be reduced or oxidized. The materials most suitable for use in slag separation were found to be dense chromium oxide and other ceramics containing a high amount of chromium oxide. [German] Mit Kohlevergasung und der anschliessenden Stromerzeugung in

  10. The United States of America and the People`s Republic of China experts report on integrated gasification combined-cycle technology (IGCC)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-12-01

    A report written by the leading US and Chinese experts in Integrated Gasification Combined Cycle (IGCC) power plants, intended for high level decision makers, may greatly accelerate the development of an IGCC demonstration project in the People`s Republic of China (PRC). The potential market for IGCC systems in China and the competitiveness of IGCC technology with other clean coal options for China have been analyzed in the report. Such information will be useful not only to the Chinese government but also to US vendors and companies. The goal of this report is to analyze the energy supply structure of China, China`s energy and environmental protection demand, and the potential market in China in order to make a justified and reasonable assessment on feasibility of the transfer of US Clean Coal Technologies to China. The Expert Report was developed and written by the joint US/PRC IGCC experts and will be presented to the State Planning Commission (SPC) by the President of the CAS to ensure consideration of the importance of IGCC for future PRC power production.

  11. Techno-economic analysis of lignite fuelled IGCC with CO{sub 2} capture. Comparing fluidized bed and entrained flow gasifiers

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Guangjian; Wu, Zhen; Zhang, Haiying [North China Electric Power Univ., Beijing (China). School of Energy and Power Engineering

    2013-07-01

    Integrated coal gasification combined cycle (IGCC) plants with pre-combustion capture of CO{sub 2} represent one of the most promising options for generating low-cost decarbonized power using bituminous coals. This work systematically quantify the effect of coal rank on the efficiency and economics of IGCC systems with CO2 capture and storage (CCS), with a special focus on comparison of systems using fluidized-bed gasifier (U-GAS) and entrained flow gasifier (Shell). It was found that the Shell IGCCs are little affect by low rank coal after pre-drying in terms of thermal efficiency and the levelized cost of electricity (LCOE) is only increase by 2-6% for lignite cases with and without CCS compared with bituminous coal cases. The specific CO{sub 2} emissions of U-GAS gasifier based lignite fuelled IGCC with CCS is 198 g/kWhe, almost two times of shell gasifier cases, mainly due to lower carbon conversion in the gasifier and the higher methane in the raw gas of gasifier. However, the total capital cost and COE of U-Gas IGCCs are 15-20% less than that of Shell IGCCs because of lower capital cost of gasifier, coal drying units and air separate units per kWe.

  12. Survey of consolidation for gas turbine re-powering combined WPP (waste power plant) project; Gas turbine repowering haikibutsu fukugo hatsuden system

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-03-01

    This report describes the survey of gas turbine re-powering combined WPP (or super WPP), which was commercialized by Gunma Prefecture for the first time as an electric power wholesaler in Japan. An outline of the survey is introduced. The system optimization for the commercialization of WPP was studied by considering waste as un-utilized energy. A successful condition and preparation method of the commercialization of a public power plant was also studied, which is a combination of the garbage collection business of a local government and an electric power generation business of a municipal company. For the introduction of the aforementioned system, the problems and supporting methods were studied by making allowance for the profitability of the WPP introduction, because they also need to deliberate it from the economical point of view as electric power companies. Based on the results of foregoing items, commercialization plans, problems encountered from the construction phase through the maintenance and service phase, and the supporting method were arranged. 30 figs., 18 tabs.

  13. IGCC power plant integrated to a Finnish pulp and paper mill. IEA Bioenergy. Techno-economic analysis activity

    Energy Technology Data Exchange (ETDEWEB)

    Koljonen, T.; Solantausta, Y. [VTT Energy, Espoo (Finland). New Energy Technologies; Salo, K.; Horvath, A. [Carbona Inc. (Finland)

    1999-11-01

    In Finland, the pulp and paper industry is the largest consumer of energy among the industries and its power demand will increase due to economical and strict environ- mental requirements. The ageing of oil and biomass boilers in Finland also represents a window of opportunity for the introduction of new environmentally sound technology with a high efficiency in power production, e.g., in biomass gasification. This site-specific study describes the technical and economic feasibility of a biomass gasification combined cycle producing heat and power for a typical Finnish pulp and paper mill. The mill produces SC (super calantered) paper 500 000 ADt/a. The paper mill employs sulphate pulp and GW (ground wood) pulp. The capacity of the pulp mill is 400 000 ADt/a (air dry ton/year) of which 120 000 ADt/a is used at the site. The heat demand of the integrate is covered by a recovery boiler and a bark boiler. A condensing steam turbine with two extractions generates electricity for the mill. The aim is to replace an old bark boiler by an IGCC (Integrated Gasification Combined Cycle) to enhance the economy and environmental performance of the power plant. The IGCC feasibility study is conducted for an pulp and paper integrate because of its suitable infrastructure for IGCC and a large amount of wood waste available at the site. For comparison, the feasibility of an IGCC integrated to a pulp mill is also assessed. The IGCC concept described is based on research and development work performed by Carbona, Inc., who acquired the rights for know-how of Enviropower, Inc. The operation and design of the IGCC concept is based on a 20 MWe gas turbine (MW151). The heat of gas turbine exhaust gas is utilised in a HRSG (Heat Recovery Steam Generator) of two pressure levels to generate steam for the pulp and paper mill and the steam turbine. The MCC power plant operates in condensing mode. The total investment cost of the IGCC plant is estimated at FIM 417 million (USD 83.4 million

  14. IGCC power plant integrated to a Finnish pulp and paper mill. IEA Bioenergy. Techno-economic analysis activity

    International Nuclear Information System (INIS)

    Koljonen, T.; Solantausta, Y.

    1999-01-01

    In Finland, the pulp and paper industry is the largest consumer of energy among the industries and its power demand will increase due to economical and strict environ- mental requirements. The ageing of oil and biomass boilers in Finland also represents a window of opportunity for the introduction of new environmentally sound technology with a high efficiency in power production, e.g., in biomass gasification. This site-specific study describes the technical and economic feasibility of a biomass gasification combined cycle producing heat and power for a typical Finnish pulp and paper mill. The mill produces SC (super calantered) paper 500 000 ADt/a. The paper mill employs sulphate pulp and GW (ground wood) pulp. The capacity of the pulp mill is 400 000 ADt/a (air dry ton/year) of which 120 000 ADt/a is used at the site. The heat demand of the integrate is covered by a recovery boiler and a bark boiler. A condensing steam turbine with two extractions generates electricity for the mill. The aim is to replace an old bark boiler by an IGCC (Integrated Gasification Combined Cycle) to enhance the economy and environmental performance of the power plant. The IGCC feasibility study is conducted for an pulp and paper integrate because of its suitable infrastructure for IGCC and a large amount of wood waste available at the site. For comparison, the feasibility of an IGCC integrated to a pulp mill is also assessed. The IGCC concept described is based on research and development work performed by Carbona, Inc., who acquired the rights for know-how of Enviropower, Inc. The operation and design of the IGCC concept is based on a 20 MWe gas turbine (MW151). The heat of gas turbine exhaust gas is utilised in a HRSG (Heat Recovery Steam Generator) of two pressure levels to generate steam for the pulp and paper mill and the steam turbine. The MCC power plant operates in condensing mode. The total investment cost of the IGCC plant is estimated at FIM 417 million (USD 83.4 million

  15. Externally-fired combined cycle: An effective coal fueled technology for repowering and new generation

    Energy Technology Data Exchange (ETDEWEB)

    Stoddard, L.E.; Bary, M.R. [Black and Veatch, Kansas City, MO (United States); Gray, K.M. [Pennsylvania Electric Co., Johnstown, PA (United States); LaHaye, P.G. [Hague International, South Portland, ME (United States)

    1995-06-01

    The Externally-Fired Combined Cycle (EFCC) is an attractive emerging technology for powering high efficiency combined gas and steam turbine cycles with coal or other ash bearing fuels. In the EFCC, the heat input to a gas turbine is supplied indirectly through a ceramic air heater. The air heater, along with an atmospheric coal combustor and ancillary equipment, replaces the conventional gas turbine combustor. A steam generator located downstream from the ceramic air heater and steam turbine cycle, along with an exhaust cleanup system, completes the combined cycle. A key element of the EFCC Development Program, the 25 MMBtu/h heat-input Kennebunk Test Facility (KTF), has recently begun operation. The KTF has been operating with natural gas and will begin operating with coal in early 1995. The US Department of Energy selected an EFCC repowering of the Pennsylvania Electric Company`s Warren Station for funding under the Clean Coal Technology Program Round V. The project focuses on repowering an existing 48 MW (gross) steam turbine with an EFCC power island incorporating a 30 MW gas turbine, for a gross power output of 78 MW and a net output of 72 MW. The net plant heat rate will be decreased by approximately 30% to below 9,700 Btu/kWh. Use of a dry scrubber and fabric filter will reduce sulfur dioxide (SO{sub 2}) and particulate emissions to levels under those required by the Clean Air Act Amendments (CAAA) of 1990. Nitrogen oxides (NO{sub x}) emissions are controlled by the use of staged combustion. The demonstration project is currently in the engineering phase, with startup scheduled for 1997. This paper discusses the background of the EFCC, the KTF, the Warren Station EFCC Clean Coal Technology Demonstration Project, the commercial plant concept, and the market potential for the EFCC.

  16. Proceedings of the coal-fired power systems 94: Advances in IGCC and PFBC review meeting. Volume 1

    Energy Technology Data Exchange (ETDEWEB)

    McDaniel, H.M.; Staubly, R.K.; Venkataraman, V.K. [eds.

    1994-06-01

    The Coal-Fired Power Systems 94 -- Advances in IGCC and PFBC Review Meeting was held June 21--23, 1994, at the Morgantown Energy Center (METC) in Morgantown, West Virginia. This Meeting was sponsored and hosted by METC, the Office of Fossil Energy, and the US Department of Energy (DOE). METC annually sponsors this conference for energy executives, engineers, scientists, and other interested parties to review the results of research and development projects; to discuss the status of advanced coal-fired power systems and future plans with the industrial contractors; and to discuss cooperative industrial-government research opportunities with METC`s in-house engineers and scientists. Presentations included industrial contractor and METC in-house technology developments related to the production of power via coal-fired Integrated Gasification Combined Cycle (IGCC) and Pressurized Fluidized Bed Combustion (PFBC) systems, the summary status of clean coal technologies, and developments and advancements in advanced technology subsystems, such as hot gas cleanup. A keynote speaker and other representatives from the electric power industry also gave their assessment of advanced power systems. This meeting contained 11 formal sessions and one poster session, and included 52 presentations and 24 poster presentations. Volume I contains papers presented at the following sessions: opening commentaries; changes in the market and technology drivers; advanced IGCC systems; advanced PFBC systems; advanced filter systems; desulfurization system; turbine systems; and poster session. Selected papers have been processed separately for inclusion in the Energy Science and Technology Database.

  17. Model Based Optimal Sensor Network Design for Condition Monitoring in an IGCC Plant

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, Rajeeva; Kumar, Aditya; Dai, Dan; Seenumani, Gayathri; Down, John; Lopez, Rodrigo

    2012-12-31

    This report summarizes the achievements and final results of this program. The objective of this program is to develop a general model-based sensor network design methodology and tools to address key issues in the design of an optimal sensor network configuration: the type, location and number of sensors used in a network, for online condition monitoring. In particular, the focus in this work is to develop software tools for optimal sensor placement (OSP) and use these tools to design optimal sensor network configuration for online condition monitoring of gasifier refractory wear and radiant syngas cooler (RSC) fouling. The methodology developed will be applicable to sensing system design for online condition monitoring for broad range of applications. The overall approach consists of (i) defining condition monitoring requirement in terms of OSP and mapping these requirements in mathematical terms for OSP algorithm, (ii) analyzing trade-off of alternate OSP algorithms, down selecting the most relevant ones and developing them for IGCC applications (iii) enhancing the gasifier and RSC models as required by OSP algorithms, (iv) applying the developed OSP algorithm to design the optimal sensor network required for the condition monitoring of an IGCC gasifier refractory and RSC fouling. Two key requirements for OSP for condition monitoring are desired precision for the monitoring variables (e.g. refractory wear) and reliability of the proposed sensor network in the presence of expected sensor failures. The OSP problem is naturally posed within a Kalman filtering approach as an integer programming problem where the key requirements of precision and reliability are imposed as constraints. The optimization is performed over the overall network cost. Based on extensive literature survey two formulations were identified as being relevant to OSP for condition monitoring; one based on LMI formulation and the other being standard INLP formulation. Various algorithms to solve

  18. Optimal control of a repowered vehicle: Plug-in fuel cell against plug-in hybrid electric powertrain

    Energy Technology Data Exchange (ETDEWEB)

    Tribioli, L., E-mail: laura.tribioli@unicusano.it; Cozzolino, R. [Dept. of Industrial Engineering, University of Rome Niccolo’ Cusano (Italy); Barbieri, M. [Engineering Dept., University of Naples Parthenope, Centro Direzionale-Isola C4, 80143 Naples (Italy)

    2015-03-10

    This paper describes two different powertrain configurations for the repowering of a conventional vehicle, equipped with an internal combustion engine (ICE). A model of a mid-sized ICE-vehicle is realized and then modified to model both a parallel plug-in hybrid electric powertrain and a proton electrolyte membrane (PEM) fuel cell (FC) hybrid powertrain. The vehicle behavior under the application of an optimal control algorithm for the energy management is analyzed for the different scenarios and results are compared.

  19. Have Local Government and Public Expectations of Wind Energy Project Benefits Been Met? Implications for Repowering Schemes

    Czech Academy of Sciences Publication Activity Database

    Frantál, Bohumil

    2014-01-01

    Roč. 16, č. 3 (2014) ISSN 1523-908X R&D Projects: GA MŠk EE2.3.20.0025 Institutional support: RVO:68145535 Keywords : wind energy * local acceptance * repowering * outcome fairness Subject RIV: DE - Earth Magnetism, Geodesy, Geography Impact factor: 1.510, year: 2014 http://www.tandfonline.com/doi/full/10.1080/1523908X.2014.936583#.VE421xZh4cs

  20. Optimal control of a repowered vehicle: Plug-in fuel cell against plug-in hybrid electric powertrain

    International Nuclear Information System (INIS)

    Tribioli, L.; Cozzolino, R.; Barbieri, M.

    2015-01-01

    This paper describes two different powertrain configurations for the repowering of a conventional vehicle, equipped with an internal combustion engine (ICE). A model of a mid-sized ICE-vehicle is realized and then modified to model both a parallel plug-in hybrid electric powertrain and a proton electrolyte membrane (PEM) fuel cell (FC) hybrid powertrain. The vehicle behavior under the application of an optimal control algorithm for the energy management is analyzed for the different scenarios and results are compared

  1. Economic evaluation of pre-combustion CO2-capture in IGCC power plants by porous ceramic membranes

    International Nuclear Information System (INIS)

    Franz, Johannes; Maas, Pascal; Scherer, Viktor

    2014-01-01

    Highlights: • Process simulations of IGCC with pre-combustion capture via membranes were done. • Most promising technology is the water–gas-shift-membrane-reactor (WGSMR). • Energetic evaluations showed minimum efficiency loss of 5.8%-points for WGSMR. • Economic evaluations identified boundary limits of membrane technology. • Cost of electricity for optimum WGSMR-case is 57 €/MW h under made assumptions. - Abstract: Pre-combustion-carbon-capture is one of the three main routes for the mitigation of CO 2 -emissions by fossil fueled power plants. Based on the data of a detailed technical evaluation of CO 2 -capture by porous ceramic membranes (CM) and ceramic membrane reactors (WGSMR) in an Integrated-Gasification-Combined-Cycle (IGCC) power plant this paper focuses on the economic effects of CO 2 -abatement. First the results of the process simulations are presented briefly. The analysis is based on a comparison with a reference IGCC without CO 2 -capture (dry syngas cooling, bituminous coal, efficiency of 47.4%). In addition, as a second reference, an IGCC process with CO 2 removal based on standard Selexol-scrubbing is taken into account. The most promising technology for CO 2 -capture by membranes in IGCC applications is the combination of a water gas shift reactor and a H 2 -selective membrane into one water gas shift membrane reactor. For the WGSRM-case efficiency losses can be limited to about 6%-points (including losses for CO 2 compression) for a CO 2 separation degree of 90%. This is a severe reduction of the efficiency loss compared to Selexol (10.3% points) or IGCC–CM (8.6% points). The economic evaluation is based on a detailed analysis of investment and operational costs. Parameters like membrane costs and lifetime, costs of CO 2 -certificates and annual operating hours are taken into account. The purpose of these evaluations is to identify the minimum cost of electricity for the different capture cases for the variation of the boundary

  2. Repowering hydro

    International Nuclear Information System (INIS)

    Lagassa, G.

    1992-01-01

    This article examines the current market for equipment and services to retrofit existing hydroelectric plants with modern equipment and evaluating, upgrading, or rehabilitating dams. The topics of the article include the current markets, the consulting engineer's role, the impetus for the market, and the future of the market for site upgrading and equipment refurbishing

  3. [Tampa Electric Company IGCC project]. 1996 DOE annual technical report, January--December 1996

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-12-31

    Tampa Electric Company`s Polk Power Station Unit 1 (PPS-1) Integrated Gasification Combined Cycle (IGCC) demonstration project uses a Texaco pressurized, oxygen-blown, entrained-flow coal gasifier to convert approximately 2,000 tons per day of coal to syngas. The gasification plant is coupled with a combined cycle power block to produce a net 250 MW electrical power output. Coal is slurried in water, combined with 95% pure oxygen from an air separation unit, and sent to the gasifier to produce a high temperature, high pressure, medium-Btu syngas with a heat content of about 250 BTUs/cf (HHV). The syngas then flows through a high temperature heat recovery unit which cools the syngas prior to its entering the cleanup systems. Molten coal ash flows from the bottom of the high temperature heat recovery unit into a water-filled quench chamber where it solidifies into a marketable slag by-product. Approximately 10% of the raw, hot syngas at 900 F is designed to pass through an intermittently moving bed of metal-oxide sorbent which removes sulfur-bearing compounds from the syngas. PPS-1 will be the first unit in the world to demonstrate this advanced metal oxide hot gas desulfurization technology on a commercial unit. The emphasis during 1996 centered around start-up activities.

  4. Puertollano IGCC Power Plant; Central de Gasificacion Integrada en Ciclo Combinado de Puertollano

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-07-01

    The Puertollano IGCC Power Plant, rated 335 MW and located in Puertollano, Ciudad Real, in the central area of Spain, is a project led by ELCOGAS, a company incorporated by the European utilities ENDESA, ELECTRICITE DE FRANCE, IBERDROLA HIDROCANTABRICO ELECTRICIDADE DE PURTUGAL, ENEL and NATIONAL POWER and the technology and equipment suppliers SIEMENS, KRUPP UHDE and BABCOCK WILCOX ESPANOLA. IGCC technology is based in a process of coal gasification to obtain a clean combustion synthetic gas, integrated with a combined cycle, agas and steam, electricity-generating unit. The energy efficiency which is aimed to achieve at the Plant is 46% in ISO conditions. The Gasification unit uses the process of pressurised entrained flow for coal gasification. The gas is produced by the reaction of coal with oxygen at high temperatures, of up to 1600 degree centigree. This process is capable of gasifying a wide variety of types and qualities of coal for the production of a synthetic fuel gas. In the case of Puertollano, the raw fuel is a 50% mixture by weight of local coal and petroleum coke. The oxygen needed in the process and the nitrogen used for covering the fuel is generated in the Air Separation. The Gas Cleaning and Sulphur Recovery Unit clean the gases from contaminants and solid particles before to send them to the Gas Turbine. The clean gas is burnt in gas turbine of the Combined Cycle Plant, producing electricity. The exhaust gases feed a heat recovery steam generator, which produces steam used to generate additional electricity in a conventional steam turbine. The gas turbine is capable of operating both with synthetic gas and with natural gas, allowing operation flexibility. The net output of the plant up to December 1999 was 3.061 GWh, from them 344 GWh were produced with synthetic gas. This project has an important technological value, being the first power plant which uses coal gasification to feed a combined cycle in Spain and being also the biggest power plant

  5. Unconventional Coal in Wyoming: IGCC and Gasification of Direct Coal Liquefaction Residue

    Science.gov (United States)

    Schaffers, William Clemens

    Two unconventional uses for Wyoming Powder River Basin coal were investigated in this study. The first was the use of coal fired integrated gasification combined cycle (IGCC) plants to generate electricity. Twenty-eight different scenarios were modeled using AspenPlusRTM software. These included slurry, mechanical and dried fed gasifiers; Wyodak and Green River coals, 0%, 70%, and 90% CO2 capture; and conventional evaporative vs air cooling. All of the models were constructed on a feed basis of 6,900 tons of coal per day on an "as received basis". The AspenPlus RTM results were then used to create economic models using Microsoft RTM Excel for each configuration. These models assumed a 3 year construction period and a 30 year plant life. Results for capital and operating costs, yearly income, and internal rates of return (IRR) were compared. In addition, the scenarios were evaluated to compare electricity sales prices required to obtain a 12% IRR and to determine the effects of a carbon emissions tax on the sales price. The second part of the study investigated the gasification potential of residue remaining from solvent extraction or liquefaction of Powder River Basin Coal. Coal samples from the Decker mine on the Wyoming-Montana border were extracted with tetralin at a temperature of 360°C and pressure of 250 psi. Residue from the extraction was gasified with CO2 or steam at 833°C, 900°C and 975°C at pressures of 0.1 and 0.4 MPa. Product gases were analyzed with a mass spectrometer. Results were used to determine activation energies, reaction order, reaction rates and diffusion effects. Surface area and electron microscopic analyses were also performed on char produced from the solvent extraction residue.

  6. Degradation of TBC Systems in Environments Relevant to Advanced Gas Turbines for IGCC Systems

    Energy Technology Data Exchange (ETDEWEB)

    Gleeson, Brian [Univ. of Pittsburgh, PA (United States)

    2014-09-30

    Air plasma sprayed (APS) thermal barrier coatings (TBCs) are used to provide thermal insulation for the hottest components in gas turbines. Zirconia stabilized with 7wt% yttria (7YSZ) is the most common ceramic top coat used for turbine blades. The 7YSZ coating can be degraded from the buildup of fly-ash deposits created in the power-generation process. Fly ash from an integrated gasification combined cycle (IGCC) system can result from coal-based syngas. TBCs are also exposed to harsh gas environments containing CO2, SO2, and steam. Degradation from the combined effects of fly ash and harsh gas atmospheres has the potential to severely limit TBC lifetimes. The main objective of this study was to use lab-scale testing to systematically elucidate the interplay between prototypical deposit chemistries (i.e., ash and its constituents, K2SO4, and FeS) and environmental oxidants (i.e., O2, H2O and CO2) on the degradation behavior of advanced TBC systems. Several mechanisms of early TBC failure were identified, as were the specific fly-ash constituents responsible for degradation. The reactivity of MCrAlY bondcoats used in TBC systems was also investigated. The specific roles of oxide and sulfate components were assessed, together with the complex interplay between gas composition, deposit chemistry and alloy reactivity. Bondcoat composition design strategies to mitigate corrosion were established, particularly with regard to controlling phase constitution and the amount of reactive elements the bondcoat contains in order to achieve optimal corrosion resistance.

  7. Process, background and design criteria of the gas cleaning at Puertollano IGCC

    Energy Technology Data Exchange (ETDEWEB)

    Pisa, J. [Elcogas, Madrid (Spain)

    1998-11-01

    The Puertollano IGCC plant selected cooling by a water-tube boiler with upstream quenching at high velocities that requires a dust-free cooling gas at not less than 250{degree}C in order not to penalise the heat recovery efficiency. A filtration system for gas dedusting in the 250{degree}C temperature range has been installed and will be commissioned at the end of 1997. The gas cleaning concept is completed with a Venturi Scrubber, a COS hydrolysis reactor and a MDEA column to strip the sulphuric acid to yield clean gas. The gasification island is based upon the PRENFLO system which is an entrained-flow system with dry feeding. The selection of the filter system arrangement considered the limited operational experience in comparable operating conditions and acknowledged the flexibility of the filter system versus the cyclone-scrubber as far as easier load variation operation, the reduction of residues needing deposition and increased slag flow, as well as easier maintenance. Additionally to the ceramic test filters in Furstenhausen (PRENFLO) and Deer Park near Houston (SHELL), ceramic candle-type filter were selected in Buggenum and at Wabash River, and for the KoBra plant. The main criteria for the selection of the filter system and the type of candle were: separation efficiency to match clean gas limits; uniform distribution of the dust-laden gas to the filters; wear-resistant routing of the dust-laden gas flow; need for a supporting structure which must cope with sudden pressure fluctuations; optimised pulse gas system; and maintenance and repair. Based upon the above criteria, the PRENFLO concept requirements and the gas turbine specification, an arrangement with two pressure filter vessels with LLB design and filter elements manufactured by Schumacher has been installed in Puertollano. 2 figs., 3 tabs.

  8. Modelling and dynamics of an air separation rectification column as part of an IGCC power plant

    Energy Technology Data Exchange (ETDEWEB)

    Seliger, B.; Hanke-Rauschenbach, R.; Hannemann, F.; Sundmacher, K. [Otto Von Guericke University, Magdeburg (Germany)

    2006-04-15

    An Integrated Gasification Combined Cycle plant (IGCC) opens the well-proven and highly efficient combined cycle process to fossil fuels, like coal or heavy refinery residues. Such a plant thereby possesses a novel linkage of typical energy engineering related units, e.g. a gas turbine and typical process engineering parts, which in the present case is an air separation plant. Different responses from the connected components can cause undesired mass flow fluctuations within the system especially during changing load demands. The cryogenic rectification column, as the core of the air separation plant, strongly affects the system's transient behaviour. The upper part of such a heat-integrated double column, a packed column with structured packing, has therefore been more closely investigated in the present paper. For this purpose, a dynamic model of such a column has been developed which is also able to describe the pressure dynamics supposedly responsible for these mass flow fluctuations. The transient behaviour of the uncontrolled column is analysed and discussed with special regard to pressure dynamics. The column pressure responds to disturbances on two different time scales. The short-term response, which is in the range of 100-200 s, is governed by the transient behaviour of the fluid dynamics and is discussed in detail. The long-term response is dominated by the nonlinear dynamics of the concentration profiles. The time constant of this response depends strongly on the direction and intensity of the disturbance and takes from 10,000 up to several 100,000 s.

  9. Development of ITM oxygen technology for integration in IGCC and other advanced power generation

    Energy Technology Data Exchange (ETDEWEB)

    Armstrong, Phillip A. [Air Products And Chemicals, Inc., Allentown, PA (United States)

    2015-03-31

    -of-the-art cryogenic air separation technology in energy-intensive applications such as IGCC with and without carbon capture.

  10. Wabash River Coal Gasification Combined Cycle Repowering Project: Clean Coal Technology Program

    International Nuclear Information System (INIS)

    1993-05-01

    The proposed project would result in a combined-cycle power plant with lower emissions and higher efficiency than most existing coal-fired power plants of comparable size. The net plant heat rate (energy content of the fuel input per useable electrical generation output; i.e., Btu/kilowatt hour) for the new repowered unit would be a 21% improvement over the existing unit, while reducing SO 2 emissions by greater than 90% and limiting NO x emissions by greater than 85% over that produced by conventional coal-fired boilers. The technology, which relies on gasified coal, is capable of producing as much as 25% more electricity from a given amount of coal than today's conventional coal-burning methods. Besides having the positive environmental benefit of producing less pollutants per unit of power generated, the higher overall efficiency of the proposed CGCC project encourages greater utilization to meet base load requirements in order to realize the associated economic benefits. This greater utilization (i.e., increased capacity factor) of a cleaner operating plant has global environmental benefits in that it is likely that such power would replace power currently being produced by less efficient plants emitting a greater volume of pollutants per unit of power generated

  11. EPA RE-Powering Mapper: Alternative Energy Potential at Cleanup Sites

    Science.gov (United States)

    The U.S. Environmental Protection Agency (EPA) Office of Land and Emergency Management??s (OLEM) Office of Communications, Partnerships and Analysis (OCPA) initiated the RE-Powering America's Land Initiative to demonstrate the enormous potential that contaminated lands, landfills, and mine sites provide for developing renewable energy in the United States. EPA developed national level site screening criteria in partnership with the U.S. Department of Energy (DOE) National Renewable Energy Laboratory (NREL) for wind, solar, biomass, and geothermal facilities. While the screening criteria demonstrate the potential to reuse contaminated land for renewable energy facilities, the criteria and data are neither designed to identify the best sites for developing renewable energy nor all-inclusive. Therefore, more detailed, site-specific analysis is necessary to identify or prioritize the best sites for developing renewable energy facilities based on the technical and economic potential. Please note that these sites were only pre-screened for renewable energy potential. The sites were not evaluated for land use constraints or current on the ground conditions. Additional research and site-specific analysis are needed to verify viability for renewable energy potential at a given site.

  12. AC transmission network expansion planning considering circuits repowering and location of capacitors

    Directory of Open Access Journals (Sweden)

    Jaime A. López-López

    2016-07-01

    Full Text Available This paper deals with the Transmission Network Expansion Planning (TNEP problem. The TNEP consists of finding a set of new circuits on a power system, which is needed to attend a future demand. In its classical version, the TNEP only considers as solution candidates the addition of new lines and transformers. The main contribution of this paper consists in the inclusion of nonconventional solution candidates, namely the repowering of existing circuits and the location of capacitor banks. To take into account these last ones an AC model of the transmission network is considered. The solution of the proposed model is carried out using a Hybrid Genetic Algorithm. Results are compared and validated with previous works in the technical literature. The test systems used are the Garver system and IEEE 24 bus system. The results obtained in both systems showed that the inclusion of the non-conventional candidates, proposed in this paper, allows to reduce the cost of network expansion. This fact may be useful as an indicator for the system planner to consider new possibilities in the expansion studies.

  13. Analysis of IGCC-based plants with carbon capture for an efficient and flexible electric power generation

    International Nuclear Information System (INIS)

    Sorgenfrei, Max

    2016-01-01

    In this work, systems based on the Integrated gasification combined cycle (IGCC) technology with carbon capture are analyzed regarding an efficient and flexible electric power generation. All analysis are related to a high-efficiency or low-cost IGCC base case with carbon capture which are both commercially available. In the high-efficiency base case, thermodynamic inefficiencies are determined based on a conventional exergy analysis. The gasifier followed by the combustion chamber of the gas turbine running on syngas are rated to the largest inefficiencies. Based on an advanced exergy analysis, the inefficiencies are split into an avoidable and unavoidable part as well as an endogenous and exogenous part. For example, it was found that about half of the inefficiencies within the gasifier are caused by other components of the overall system(exogenous part). Further investigations on the combination of both splitting types are presented. The gas turbine system is identified to be a major component and therefore a detailed model was developed using state-of-the-art technologies. Based on this model, 12 types of characteristic inefficiencies were determined and rated by their exergy destruction. Chemical-Looping Combustion (CLC) is one of the most promising technologies to enhance the available IGCC design. CLC uses composite metal particles acting as an oxygen carrier to transport oxygen from the air to the fuel gas through a redox-cycle. Thus, the inefficiencies associated with the combustion process decrease and the application of physical absorption for capturing CO 2 is replaced by an inherent CO 2 -capture. In this work, the most suitable oxygen carriers for CLC using syngas (nickel oxide and iron oxide) are analyzed at different temperatures. Moreover, different types of gasifier as well as CLC reactor designs are analyzed. Regenerating the oxygen carrier by steam and air, produces additional hydrogen from the reduction of steam which is further combusted

  14. EPA RE-Powering America's Lands: Kansas City Municipal Farm Site ₋ Biomass Power Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Hunsberger, R. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Mosey, G. [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2015-01-01

    Through the RE-Powering America's Land initiative, the economic and technical feasibility of utilizing biomass at the Kansas City, Missouri, Municipal Farm site, a group of City-owned properties, is explored. The study that none of the technologies we reviewed--biomass heat, power and CHP--are economically viable options for the Municipal Farms site. However, if the site were to be developed around a future central biomass heating or CHP facility, biomass could be a good option for the site.

  15. Thermodynamic simulation of CO{sub 2} capture for an IGCC power plant using the calcium looping cycle

    Energy Technology Data Exchange (ETDEWEB)

    Li, Y. [National Engineering Laboratory for Coal-Burning Pollutant Emission Reduction, Shandong University, Jinan (China); Zhao, C.; Ren, Q. [School of Energy and Environment, Southeast University, Nanjing (China)

    2011-06-15

    A CO{sub 2} capture process for an integrated gasification combined cycle (IGCC) power plant using the calcium looping cycle was proposed. The CO{sub 2} capture process using natural and modified limestone was simulated and investigated with the software package Aspen Plus. It incorporated a fresh feed of sorbent to compensate for the decay in CO{sub 2} capture activity during long-term cycles. The sorbent flow ratios have significant effect on the CO{sub 2} capture efficiency and net efficiency of the CO{sub 2} capture system. The IGCC power plant, using the modified limestone, exhibits higher CO{sub 2} capture efficiency than that using the natural limestone at the same sorbent flow ratios. The system net efficiency using the natural and modified limestones achieves 41.7% and 43.1%, respectively, at the CO{sub 2} capture efficiency of 90% without the effect of sulfation. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  16. Feasibility analysis of gas turbine inlet air cooling by means of liquid nitrogen evaporation for IGCC power augmentation

    International Nuclear Information System (INIS)

    Morini, Mirko; Pinelli, Michele; Spina, Pier Ruggero; Vaccari, Anna; Venturini, Mauro

    2015-01-01

    Integrated Gasification Combined Cycles (IGCC) are energy systems mainly composed of a gasifier and a combined cycle power plant. Since the gasification process usually requires oxygen as the oxidant, an Air Separation Unit (ASU) is also part of the plant. In this paper, a system for power augmentation in IGCC is evaluated. The system is based on gas turbine inlet air cooling by means of liquid nitrogen spray. In fact, nitrogen is a product of the ASU, but is not always exploited. In the proposed plant, the nitrogen is first liquefied to be used for inlet air cooling or stored for later use. This system is not characterized by the limits of water evaporative cooling systems (the lower temperature is limited by air saturation) and refrigeration cooling (the effectiveness is limited by the pressure drop in the heat exchanger). A thermodynamic model of the system is built by using a commercial code for energy conversion system simulation. A sensitivity analysis on the main parameters is presented. Finally the model is used to study the capabilities of the system by imposing the real temperature profiles of different sites for a whole year and by comparing to traditional inlet air cooling strategies. - Highlights: • Gas turbine inlet air cooling by means of liquid nitrogen spray. • Humidity condensation may form a fog which provides further power augmentation. • High peak and off peak electric energy price ratios make the system profitable

  17. Low Thermal Conductivity, High Durability Thermal Barrier Coatings for IGCC Environments

    Energy Technology Data Exchange (ETDEWEB)

    Jordan, Eric [Univ. of Connecticut, Storrs, CT (United States); Gell, Maurice [Univ. of Connecticut, Storrs, CT (United States)

    2015-01-15

    Advanced thermal barrier coatings (TBC) are crucial to improved energy efficiency in next generation gas turbine engines. The use of traditional topcoat materials, e.g. yttria-stabilized zirconia (YSZ), is limited at elevated temperatures due to (1) the accelerated undesirable phase transformations and (2) corrosive attacks by calcium-magnesium-aluminum-silicate (CMAS) deposits and moisture. The first goal of this project is to use the Solution Precursor Plasma Spray (SPPS) process to further reduce the thermal conductivity of YSZ TBCs by introducing a unique microstructural feature of layered porosity, called inter-pass boundaries (IPBs). Extensive process optimization accompanied with hundreds of spray trials as well as associated SEM cross-section and laser-flash measurements, yielded a thermal conductivity as low as 0.62 Wm⁻¹K⁻¹ in SPPS YSZ TBCs, approximately 50% reduction of APS TBCs; while other engine critical properties, such as cyclic durability, erosion resistance and sintering resistance, were characterized to be equivalent or better than APS baselines. In addition, modifications were introduced to SPPS TBCs so as to enhance their resistance to CMAS under harsh IGCC environments. Several mitigation approaches were explored, including doping the coatings with Al₂O₃ and TiO₂, applying a CMAS infiltration-inhibiting surface layer, and filling topcoat cracks with blocking substances. The efficacy of all these modifications was assessed with a set of novel CMAS-TBC interaction tests, and the moisture resistance was tested in a custom-built high-temperature moisture rig. In the end, the optimal low thermal conductivity TBC system was selected based on all evaluation tests and its processing conditions were documented. The optimal coating consisted on a thick inner layer of YSZ coating made by the SPPS process having a thermal conductivity 50% lower than standard YSZ coatings topped with a high temperature tolerant CMAS resistant gadolinium

  18. Future technological and economic performance of IGCC and FT production facilities with and without CO2 capture: Combining component based learning curve and bottom-up analysis

    NARCIS (Netherlands)

    Knoope, M.M.J.; Meerman, J.C.; Ramirez, C.A.; Faaij, A.P.C.

    2013-01-01

    This study aims to investigate the technological and economic prospects of integrated gasification facilities for power (IGCC) and Fischer–Tropsch (FT) liquid production with and without CCS over time. For this purpose, a component based experience curve was constructed and applied to identify the

  19. Map-Based Repowering and Reorganization of a Wind Resource Area to Minimize Burrowing Owl and Other Bird Fatalities

    Directory of Open Access Journals (Sweden)

    Lee Neher

    2009-10-01

    Full Text Available Wind turbines in the Altamont Pass Wind Resource Area (Alameda/Contra Costa Counties, California, USA generate about 730 GWh of electricity annually, but have been killing thousands of birds each year, including >2,000 raptors and hundreds of burrowing owls. We have developed collision hazard maps and hazard ratings of wind turbines to guide relocation of existing wind turbines and careful repowering to modern turbines to reduce burrowing owl fatalities principally, and other birds secondarily. Burrowing owls selected burrow sites lower on slopes and on smaller, shallower slopes than represented by the average 10 × 10 m2 grid cell among 187,908 grid cells sampled from 2,281,169 grid cells comprising a digital elevation model (DEM of the study area. Fuzzy logic and discriminant function analysis produced likelihood surfaces encompassing most burrowing owl burrows within a fraction of the study area, and the former corresponded with burrowing owl fatalities and the latter with other raptor fatalities. Our ratings of wind turbine hazard were more predictive of burrowing owl fatalities, but would be more difficult to implement. Careful repowering to modern wind turbines would most reduce fatalities of burrowing owls and other birds while adding about 1,000 GWh annually toward California’s 33% Renewable Portfolio Standard.

  20. Map-based repowering and reorganization of a wind resource area to minimize burrowing owl and other bird fatalities

    Energy Technology Data Exchange (ETDEWEB)

    Smallwood, K. S. [Research Ecologist, 3108 Finch Street, Davis, CA 95616 (United States); Neher, L. [Gis Specialist, Neher Consulting, 7241 34th Street, North Highlands, CA 95660 (United States); Bell, D. A. [East Bay Regional Park District, 2950 Peralta Oaks Court, Oakland, CA 94605-0381 (United States)

    2009-07-01

    Wind turbines in the Altamont Pass Wind Resource Area (Alameda/Contra Costa Counties, California, USA) generate about 730 GWh of electricity annually, but have been killing thousands of birds each year, including >2,000 raptors and hundreds of burrowing owls. We have developed collision hazard maps and hazard ratings of wind turbines to guide relocation of existing wind turbines and careful repowering to modern turbines to reduce burrowing owl fatalities principally, and other birds secondarily. Burrowing owls selected burrow sites lower on slopes and on smaller, shallower slopes than represented by the average 10 x 10 m{sup 2} grid cell among 187,908 grid cells sampled from 2,281,169 grid cells comprising a digital elevation model (DEM) of the study area. Fuzzy logic and discriminant function analysis produced likelihood surfaces encompassing most burrowing owl burrows within a fraction of the study area, and the former corresponded with burrowing owl fatalities and the latter with other raptor fatalities. Our ratings of wind turbine hazard were more predictive of burrowing owl fatalities, but would be more difficult to implement. Careful repowering to modern wind turbines would most reduce fatalities of burrowing owls and other birds while adding about 1,000 GWh annually toward California's 33% Renewable Portfolio Standard. (author)

  1. The slag from ELCOGAS IGCC thermal power plant as raw material for the synthesis of glass-ceramic materials. Part I: Thermal behavior of the IGCC slag and synthesis of the parent glass.

    Energy Technology Data Exchange (ETDEWEB)

    Aineto, M.; Acosta, A. [University of Castilla La Mancha, Ciudad Real (Spain)

    2005-12-01

    We report here the results of the first phase of investigation on the melting behavior of the IGCC slag, and the use of this slag as raw component to produce glass ceramics. The vitrifying mixture named ECSCP, is composed of 40% slag, 30% glass cullet and 30% precipitated calcium carbonate obtained as a by-product in a sugar refining plant. This mixture was melted at 1450{sup o}C to obtain the ECSCP parent glass, that was then characterized and its crystallization kinetics studied by thermal analysis. The ECSCP glass exhibit a surface mechanism of crystallization, and will be used to produce anorthite/wollastonite glass ceramics in the second part of the investigation.

  2. Degradation of TBC Systems in Environments Relevant to Advanced Gas Turbines for IGCC Systems

    Science.gov (United States)

    Bohna, Nathaniel Allan

    Plasma sprayed (PS) thermal barrier coatings (TBCs) are used to provide thermal insulation for the hottest components in gas turbines. Zirconia stabilized with 7wt% yttria (7YSZ) is the most common ceramic top coat used for turbine blades. The 7YSZ coating can be degraded by the buildup of fly-ash deposits which can arise from the fuel source (coal/biomass) used in the combustion process in gas turbines. Fly-ash from the integrated gasification combined cycle (IGCC) process can result from coal-based syngas and also from ambient air which passes through the system. TBCs are also exposed to harsh gas environments containing CO2, SO2, and steam. As presented in this thesis, degradation from the combined effects of fly-ash and harsh gas atmosphere can severely limit TBC lifetimes. It is well established that degradation at very high temperatures (≥1250°C) from deposits consisting of the oxides CaO-MgO-Al2O3-SiO 2 results from extensive liquid silicate infiltration into the porous top coat of the YSZ. This infiltration causes early failure resulting from chemical and/or mechanical damage to the ceramic layer. Damage resulting from liquid infiltration, however, is not typically considered at relatively lower temperatures around 1100°C because liquid silicates would not be expected to form from the oxides in the deposit. A key focus of this study is to assess the mode and extent of TBC degradation at 1100°C in cases when some amount of liquid forms owing to the presence of K2SO4 as a minor ash constituent. Two types of liquid infiltrations are observed depending on the principal oxide (i.e., CaO or SiO2) in the deposit. The degradation is primarily the result of mechanical damage, which results from infiltration caused by the interaction of liquid K2SO4 with either the CaO or SiO2. The TBCs used in this work are representative of commonly used coatings used in the hottest sections of land-based gas turbines. The specimens consist of 7YSZ top coats deposited on

  3. Questionnaire regarding the international Freiberg conference on IGCC and XtL technologies. Analysis of 75 questionnaires

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-07-01

    The Puertollano IGCC Plant, owned by ELCOGAS, uses a mixture (50/50% weight) of local coal with high content of ash (approximately 45%) and pet-coke to be fed into its pressurised entrained flow gasifier. Ash is removed from the bottom of the gasifier as vitrified slag although a fraction is converted into fly ash (2.5-3 t/h) and entrained by the syngas. In order to remove this fly ash, it is filtered in two candle filter vessels with more than 1,000 candles each, using nitrogen for on-line cleaning. The filtering system suffers some malfunctions resulting in blinding of the internal candle surface and increasing of the candle DP. The model of candle filter was changed and modifications were performed without the desired results. Therefore, the identification of suitable hot gas filtration technologies capable of overcoming current and future severe operational constraints experienced is of the utmost importance for IGCC units. In this sense, a pilot plant which allows the performance of alternative filtering elements tests, pulse cleaning strategies, on-line particulate monitoring and off-cleaning procedures has come into operation at the ESI-University of Seville facilities. The design has been conceived as a versatile pilot unit, in order to hold both bags and ceramic candles which are to be tested in a wide range of operating conditions. The pilot is processing air laden with real fly ash provided by ELCOGAS, and high pressure nitrogen for the cleaning operation. This paper describes the design and operation of the pilot as well as the testing plan currently being carried out. (orig.)

  4. Multi-fuel multi-product operation of IGCC power plants with carbon capture and storage (CCS)

    International Nuclear Information System (INIS)

    Cormos, Ana-Maria; Dinca, Cristian; Cormos, Calin-Cristian

    2015-01-01

    This paper investigates multi-fuel multi-product operation of IGCC plants with carbon capture and storage (CCS). The investigated plant designs co-process coal with different sorts of biomass (e.g. sawdust) and solid wastes, through gasification, leading to different decarbonised energy vectors (power, hydrogen, heat, substitute natural gas etc.) simultaneous with carbon capture. Co-gasification of coal with different renewable energy sources coupled with carbon capture will pave the way towards zero emissions power plants. The energy conversions investigated in the paper were simulated using commercial process flow modelling package (ChemCAD) in order to produce mass and energy balances necessary for the proposed evaluation. As illustrative cases, hydrogen and power co-generation and Fischer–Tropsch fuel synthesis (both with carbon capture), were presented. The case studies investigated in the paper produce a flexible ratio between power and hydrogen (in the range of 400–600 MW net electricity and 0–200 MW th hydrogen considering the lower heating value) with at least 90% carbon capture rate. Special emphasis were given to fuel selection criteria for optimisation of gasification performances (fuel blending), to the selection criteria for gasification reactor in a multi-fuel multi-product operation scenario, modelling and simulation of whole process, to thermal and power integration of processes, flexibility analysis of the energy conversion processes, in-depth techno-economic and environmental assessment etc. - Highlights: • Assessment of IGCC-based energy vectors poly-generation systems with CCS. • Optimisation of gasification performances and CO 2 emissions by fuel blending. • Multi-fuel multi-product operation of gasification plants

  5. Feasibility Study for the Ivano-Frankivsk District Heating Repowering: Analysis of Options

    Energy Technology Data Exchange (ETDEWEB)

    Markel, L.; Popelka, A.; Laskarevsky, V.

    2002-03-20

    Part of the U.S. Initiative on Joint Implementation with the Ukraine Inter-Ministerial Commission on Climate Change, financed by the US Department of Energy. The project was implemented by a team consisting of the US company SenTech, Inc. and the Ukrainian company Esco-West. The main objective of the effort was to assess available alternatives of Ivano-Frankivsk (I-F) District Heating repowering and provide information for I-F's investment decision process. This study provides information on positive and negative technical and economic aspects of available options. Three options were analyzed for technical merit and economic performance: 1. Installation of cogeneration system based on Gas Turbine (GT) and Heat Recovery Heat Exchanger with thermal capacity of 30 MW and electrical capacity of 13.5 MW. This Option assumes utilization of five existing boilers with total capacity of 221 MW. Existing boilers will be equipped with modern controls. Equipment in this Option was sized for longest operating hours, about 8000 based on the available summer baseload. 2. Installation of Gas Turbine Combined Cycle (GTCC) and Heat Recovery Steam Generator (HRSG) with thermal capacity 45 MW and electrical capacity of 58.7 MW. This Option assumes utilization of five existing boilers with total capacity of 221 MW. Existing boilers will be equipped with modern controls. The equipment was sized for medium, shoulder season thermal load, and some cooling was assumed during the summer operation for extension of operating hours for electricity production. 3. Retrofit of six existing boilers (NGB) with total thermal capacity of 255.9 MW by installation of modern control system and minor upgrades. This option assumes only heat production with minimum investment. The best economic performance and the largest investment cost would result from alternative GTCC. This alternative has positive Net Present Value (NPV) with discount rate lower than about 12%, and has IRR slightly above 12%. The

  6. Recovery Ce from Ce - TBP Used Oxalic Acid

    International Nuclear Information System (INIS)

    Purwani, MV; Subagiono, R.; Suyanti

    2007-01-01

    Recovery or stripping Ce from Ce - TBP product of monazite sand used oxalic acid. Ce - TBP as organic phase and oxalic acid as aqueous phase and as strong precipitant compound to precipitate metal element. The stripping product as Ce - oxalic precipitate. The influence parameter were percentage of oxalic acid, volume ratio of Ce-TBP with oxalic acid, time and rate of stripping. At stripping of 25 ml Ce - TBP used oxalic acid, the optimum condition were achieve at using 5% oxalic acid, volume ratio of Ce - TBP : 5% oxalic acid = 1 : 1, time of stripping 7.5 minute and rate of stripping 150 rpm. At the optimum condition was obtained the recovery efficiency was 100%. (author)

  7. Report of year 2000 version on feasibility study for joint implementation. Repowering project of Ashuganji Thermal Power Station

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-03-01

    Discussions were given on the repowering project of Ashuganji Thermal Power Station in the People's Republic of Bangladesh to link the project to the clean development mechanism (CDM). The project calls for adding gas turbines respectively having output of 31 MW to the existing units No. 3, 4 and 5 (each having an output of 150 MW) to make the plant into the waste gas re-combustion type compound cycle system. The construction cost would be 140 billion yen. The annual reduction of fuel per unit would be 28 kt, which can result in reduction of 2.1 million tons from the three units over the period of 25 years. The annual reduction in CO2 emission from a unit would be 77 kt, resulting in reduction of 5.8 million tons from the three units over 25 years. The return on investment effect was evaluated. In the main case (the output increase as a result of the repowering is used to supplement the current power supply shortage), the required period to recover the investment will be ten years on the basis of introducing private sector fund, but the internal profitability would be 8.09%, being far below the discount rate of 15%, and the current discount worth is also negative, hence the project would not be feasible. However, since there are no problems in repaying the loans, application of the low-interest special Yen loan is desired to eliminate the state of chronic power shortage. The discharge right transaction case (550 yen/ton of CO2) was also found unworkable to recover the investment. (NEDO)

  8. Report of year 2000 version on feasibility study for joint implementation. Repowering project of Ashuganji Thermal Power Station

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-03-01

    Discussions were given on the repowering project of Ashuganji Thermal Power Station in the People's Republic of Bangladesh to link the project to the clean development mechanism (CDM). The project calls for adding gas turbines respectively having output of 31 MW to the existing units No. 3, 4 and 5 (each having an output of 150 MW) to make the plant into the waste gas re-combustion type compound cycle system. The construction cost would be 140 billion yen. The annual reduction of fuel per unit would be 28 kt, which can result in reduction of 2.1 million tons from the three units over the period of 25 years. The annual reduction in CO2 emission from a unit would be 77 kt, resulting in reduction of 5.8 million tons from the three units over 25 years. The return on investment effect was evaluated. In the main case (the output increase as a result of the repowering is used to supplement the current power supply shortage), the required period to recover the investment will be ten years on the basis of introducing private sector fund, but the internal profitability would be 8.09%, being far below the discount rate of 15%, and the current discount worth is also negative, hence the project would not be feasible. However, since there are no problems in repaying the loans, application of the low-interest special Yen loan is desired to eliminate the state of chronic power shortage. The discharge right transaction case (550 yen/ton of CO2) was also found unworkable to recover the investment. (NEDO)

  9. Policy for rekindling and re-powering of small scale hydroelectric power plants; Politica de rejuvenescimento e repotenciacao de PCH`s

    Energy Technology Data Exchange (ETDEWEB)

    Souza, Wanderley I. de [Companhia Paulista de Forca e Luz (CPFL), Campinas, SP (Brazil). Div. de Geracao

    1997-12-31

    The demand of electric energy comes increasing gradually and the offer of energy with of growth of the market, becomes a product, a great concern. In this matter Small Hydroelectric Power Plant SHP`s can be fundamental to offer support to the electric section, but these small sources of energy need to be adapting rekindling and repowering, being used of new market technologies and of economic studies that can give reliability and speed in the evaluations of the processes. (author)

  10. Design and evaluation of an IGCC power plant using iron-based syngas chemical-looping (SCL) combustion

    International Nuclear Information System (INIS)

    Sorgenfrei, Max; Tsatsaronis, George

    2014-01-01

    Highlights: • A new concept for power generation including carbon capture was found. • The air reactor temperature significantly influences the net efficiency. • The use of a CO 2 turbine decreases the net efficiency. • Compared to a conventional IGCC with 90% CO 2 capture the net efficiency increases. - Abstract: Chemical-looping combustion (CLC) is a novel and promising combustion technology with inherent separation of the greenhouse gas CO 2 . This paper focuses on the design and thermodynamic evaluation of an integrated gasification combined-cycle (IGCC) process using syngas chemical looping (SCL) combustion for generating electricity. The syngas is provided by coal gasification; the gas from the gasifier is cleaned using high-temperature gas desulfurization (HGD). In this study, the oxygen carrier iron oxide (Fe 2 O 3 ) is selected to oxidize the syngas in a multistage moving-bed reactor. The resulting reduced iron particles then consist of FeO and Fe 3 O 4 . To create a closed-cycle operation, these particles are partially re-oxidized with steam in a fluidized-bed regenerator to pure Fe 3 O 4 and then fully re-oxidized in a fluidized-bed air combustor to Fe 2 O 3 . One advantage of this process is the co-production of hydrogen diluted with water vapor within the steam regenerator. Both the HGD and CLC systems are not under commercial operation so far. This mixture is fed to a gas turbine for the purpose of generating electricity. The gas turbine is expected to exhibit low NO x emissions due to the high ratio of water in the combustion chamber. Cooling the flue gas in the HRSG condenses the water vapor to yield high-purity CO 2 for subsequent compression and disposal. To evaluate the net efficiency, two conventional syngas gasifiers are considered, namely the BGL slagging gasifier and the Shell entrained-flow gasifier. The option of using a CO 2 turbine after the SCL-fuel reactor is also investigated. A sensitivity analysis is performed on the SCL

  11. CE-BEMS

    DEFF Research Database (Denmark)

    Mohamed, Nader; Lazarova-Molnar, Sanja; Al-Jaroodi, Jameela

    2016-01-01

    and costs savings in smart buildings significantly depend on the monitoring and control methods used in the installed BEMS. This paper proposes a Cloud-Enabled BEMS (CE-BEMS) for Smart Buildings. This system can utilize cloud computing to provide enhanced management mechanisms and features for energy...... savings in smart buildings. This system is connected to the cloud to have access to a number of advanced cloud-based services to enhance energy management in smart buildings. In this paper, we discuss the current limitations of BEMS, the conceptual design of the proposed system, and the advantages......Energy consumption in smart buildings is monitored and controlled using Building Energy Management Systems (BEMS). A BEMS provides a set of methods to monitor and control a building's energy needs while maintaining a good quality of living in all of the building's spaces. Energy efficiency...

  12. Heat Integration of the Water-Gas Shift Reaction System for Carbon Sequestration Ready IGCC Process with Chemical Looping

    Energy Technology Data Exchange (ETDEWEB)

    Juan M. Salazara; Stephen E. Zitney; Urmila M. Diwekara

    2010-01-01

    Integrated gasification combined cycle (IGCC) technology has been considered as an important alternative for efficient power systems that can reduce fuel consumption and CO2 emissions. One of the technological schemes combines water-gas shift reaction and chemical-looping combustion as post gasification techniques in order to produce sequestration-ready CO2 and potentially reduce the size of the gas turbine. However, these schemes have not been energetically integrated and process synthesis techniques can be applied to obtain an optimal flowsheet. This work studies the heat exchange network synthesis (HENS) for the water-gas shift reaction train employing a set of alternative designs provided by Aspen energy analyzer (AEA) and combined in a process superstructure that was simulated in Aspen Plus (AP). This approach allows a rigorous evaluation of the alternative designs and their combinations avoiding all the AEA simplifications (linearized models of heat exchangers). A CAPE-OPEN compliant capability which makes use of a MINLP algorithm for sequential modular simulators was employed to obtain a heat exchange network that provided a cost of energy that was 27% lower than the base case. Highly influential parameters for the pos gasification technologies (i.e. CO/steam ratio, gasifier temperature and pressure) were calculated to obtain the minimum cost of energy while chemical looping parameters (oxidation and reduction temperature) were ensured to be satisfied.

  13. CE and nanomaterials - Part II: Nanomaterials in CE.

    Science.gov (United States)

    Adam, Vojtech; Vaculovicova, Marketa

    2017-10-01

    The scope of this two-part review is to summarize publications dealing with CE and nanomaterials together. This topic can be viewed from two broad perspectives, and this article is trying to highlight these two approaches: (i) CE of nanomaterials, and (ii) nanomaterials in CE. The second part aims at summarization of publications dealing with application of nanomaterials for enhancement of CE performance either in terms of increasing the separation resolution or for improvement of the detection. To increase the resolution, nanomaterials are employed as either surface modification of the capillary wall forming open tubular column or as additives to the separation electrolyte resulting in a pseudostationary phase. Moreover, nanomaterials have proven to be very beneficial for increasing also the sensitivity of detection employed in CE or even they enable the detection (e.g., fluorescent tags of nonfluorescent molecules). © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Using renewables and the co-production of hydrogen and electricity from CCS-equipped IGCC facilities, as a stepping stone towards the early development of a hydrogen economy

    International Nuclear Information System (INIS)

    Haeseldonckx, Dries; D'haeseleer, William

    2010-01-01

    In this paper, specific cases for the interaction between the future electricity-generation mix and a newly-developing hydrogen-production infrastructure is modelled with the model E-simulate. Namely, flexible integrated-gasification combined-cycle units (IGCC) are capable of producing both electricity and hydrogen in different ratios. When these units are part of the electricity-generation mix and when they are not operating at full load, they could be used to produce a certain amount of hydrogen, avoiding the costly installation of new IGCC units for hydrogen production. The same goes for the massive introduction of renewable energies (especially wind), possibly generating excess electricity from time to time, which could then perhaps be used to produce hydrogen electrolytically. However, although contra-intuitive, the interaction between both 'systems' turns out to be almost negligible. Firstly, it is shown that it is more beneficial to use IGCC facilities to produce hydrogen with, rather than (excess) wind-generated electricity due to the necessary electrolyser investment costs. But even flexible IGCC facilities do not seem to contribute substantially to the early development of a hydrogen economy. Namely, in most scenarios - which are combinations of a wide range of fuel prices and carbon taxes - one primary-energy carrier (natural gas or coal) seems to be dominant, pushing the other, and the corresponding technologies such as reformers or IGCCs, out of the market. (author)

  15. CE Challenges : Work to Do

    NARCIS (Netherlands)

    Stjepandic, J; Verhagen, W.J.C.; Wognum, P.M.

    2015-01-01

    CE has been used for more than two decades now. Despite many successes and advantages, there are still many challenges to be addressed. These challenges are both technical and organisational. In the paper we will address the current challenges of CE. Many challenges

  16. Promotion of the formation of environmentally friendly energy community (FY 2000). Demonstration of the gas turbine repowering waste combined power generation technology; 2000 nendo kankyo chowagata energy community keisei sokushin seika hokokusho. Gas turbine repowering haikibutsu fukugo hatsuden gijutsu jissho

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-03-01

    Demonstrative operation was conducted of the super waste power generation system in which the low temperature steam generated in waste incinerator is raised in temperature using the combustion exhaust gas emitted after the power generation using another gas turbine for conducting the steam turbine power generation with high efficiency. The FY 2000 results were summed up. In the demonstrative operation, operation and data acquisition/analysis were conducted following the previous fiscal year by 25MW class gas turbine repowering waste combined power generation facilities (Takahama power plant). Further, four years after the start of operation, the secular variation was studied by disassembly/inspection of equipment. As a result of the operation, the thermal efficiency was approximately 35%, much higher than the existing waste power generation. It was verified that the power system was maintained by the same maintenance as that of the ordinary power system. Moreover, the important point of this system is that no special corrosion resistant materials are used and that the high-efficiency waste power generation was demonstrated by combining the existing equipment. It can be said that the super waste power system has high qualities for forming energy community as a regionally dispersed stabilized power source. (NEDO)

  17. Aerodynamics and Heat Transfer Studies of Parameters Specific to the IGCC-Requirements: Endwall Contouring, Leading Edge and Blade Tip Ejection under Rotating Turbine Conditions

    Energy Technology Data Exchange (ETDEWEB)

    Schobeiri, Meinhard; Han, Je-Chin

    2014-09-30

    This report deals with the specific aerodynamics and heat transfer problematic inherent to high pressure (HP) turbine sections of IGCC-gas turbines. Issues of primary relevance to a turbine stage operating in an IGCC-environment are: (1) decreasing the strength of the secondary flow vortices at the hub and tip regions to reduce (a), the secondary flow losses and (b), the potential for end wall deposition, erosion and corrosion due to secondary flow driven migration of gas flow particles to the hub and tip regions, (2) providing a robust film cooling technology at the hub and that sustains high cooling effectiveness less sensitive to deposition, (3) investigating the impact of blade tip geometry on film cooling effectiveness. The document includes numerical and experimental investigations of above issues. The experimental investigations were performed in the three-stage multi-purpose turbine research facility at the Turbomachinery Performance and Flow Research Laboratory (TPFL), Texas A&M University. For the numerical investigations a commercial Navier-Stokes solver was utilized.

  18. Lattice dynamics of γ--Ce

    International Nuclear Information System (INIS)

    Gould, T.A.

    1978-08-01

    The phonon and magnetic measurements described in the thesis produced the following significant results concerning the lattice dynamical and magnetic properties of γ-Ce. The phonon spectrum is relatively soft, which is consistent with results obtained for CeSn 3 . The L [110] and T [111] branches of the dispersion curve are anomalous. The C 11 and C 44 elastic constants are quite close in value. No discrete magnetic excitations were observed. The magnetic scattering is qualitatively similar to the results from Ce 0 . 74 Th 0 . 26 , however, GAMMA/sub Ce/ less than GAMMA/sub Ce-Th/. The various lattice dynamical and magnetic similarities among γ-Ce, CeSn 3 , and Ce 0 . 74 Th 0 . 26 are mixed valence compounds. Therefore, a complete theoretical description of the observed properties of Ce and its compounds may provide a basis for understanding a whole class of mixed valence materials

  19. Magnetic behaviour of cerium in Ce2 Sn5 and Ce3 Sn7, surstructures of Ce Sn3

    International Nuclear Information System (INIS)

    Stunault, A.

    1988-07-01

    The compound studied, Ce 2 Sn 5 and Ce 3 Sn 7 are both orthorhombic, surstructure of cubic Ce Sn 3 . Magnetic susceptibility measurements show in both compounds an antiferromagnetic order at low temperature and magnetization shows a high anisotropy. Magnetization densities are determined by polarized neutron diffraction. The cerium site which has two Ce atoms as nearest neighbourgs carries all the magnetism in both structures. For Ce 2 Sn 5 moments are directed as the high magnetization axis and structure is modulated. Ce 3 Sn 7 presents a simple antiferromagnetic order but moment are directed as low magnetization axis. Various transitions towards a ferromagnetic order are presented. Results are interpreted by measuring the difference between energy levels of crystalline field. A model of crystalline field and isotrope exchange agrees well with Ce 3 Sn 7 , but for Ce 2 Sn 7 it is necessary to reduce the magnetic moment which is typical of the Kondo effect [fr

  20. Green power production by co-gasification of biomass in coal-fired oxygen-blown entrained-flow based IGCC processes

    Energy Technology Data Exchange (ETDEWEB)

    Van Ree, R; Korbee, R; De Smidt, R P; Jansen, D [ECN Fuels Conversion and Environment, Petten (Netherlands); Baumann, H R; Ullrich, N [Krupp Uhde, Dortmund (Germany); Haupt, G; Zimmerman, [Siemens, Erlangen (Germany)

    1998-11-01

    The use of coal for large scale power production meets a growing environmental concern. In spite of the fact that clean coal conversion technologies integrated with high-efficiency power production facilities, such as IGCC, are developed, the aim for sustainable development strives for a power production system based on renewable energy sources. One of the most promising renewable energy sources that can be used in the Netherlands is biomass, i.e. organic waste materials and/or energy crops. To accelerate the introduction of this material, in a technical and economically acceptable way, co-gasification with fossil fuels, in particular coal, in large scale IGCC processes is considered. In this paper the technical feasibility, economic profitability, and environmental acceptability of co-gasification of biomass in coal-fired oxygen-blown entrained-flow based IGM is discussed. Both a base-case coal-fired oxygen-blown entrained-flow based IGCC process - showing strong resemblance to the Puertollano IGCC plant in Spain - and three co-gasification concepts, viz.: (1) a concept with separate dry coal and biomass feeding systems, (2) a concept with a combined dry coal/biomass-derived pyrolysis char feeding system, and (3) a concept with parallel biomass pre-treatment/gasification and combined fuel gas clean-up/power production, were defined for further consideration. The base-case system and the co-gasification concepts as well are modelled in the flowsheet simulation package ASPEN{sup +}. Steady-state integral system calculations resulted in an overall net electrical plant efficiency for the base-case system of 50. 1 %LHV (48.3 %HHV). Replacing about 10 % of the total thermal plant input (coal) by biomass (willow) resulted in a decrease of the overall net electrical plant efficiency of 1.4 to 2.1 %-points LHV, avoided specific CO2 emissions of 40-49 g/kWh{sub e}, and total avoided CO2 emissions of about 129 to 159 kt/a, all depending on the co-gasification concept

  1. Superdeformed bands in 130Ce

    International Nuclear Information System (INIS)

    Paul, E.S.; Semple, A.T.; Boston, A.J.; Joss, D.T.; Nolan, P.J.; Shepherd, S.L.

    1997-01-01

    Four superdeformed bands have been assigned to 130 Ce following a high-statistics γ-ray study using the EUROGAM II spectrometer. The strongest band exhibits two distinct backbends which, in one scenario, may be interpreted as crossings between high-j N = 6 neutron orbitals (νi 13/2 ) and low-j N = 4 orbitals (νd 3/2 ) in an unpaired system. (author)

  2. Magnetic behaviour of new Ce compounds

    Energy Technology Data Exchange (ETDEWEB)

    Sampathkumaran, E V [Tata Inst. of Fundamental Research, Bombay (India); Mallik, R [Tata Inst. of Fundamental Research, Bombay (India)

    1996-07-01

    We report initial results of our investigation on the magnetic behaviour of some new Ce compounds. The compounds, CeIr{sub 2}B{sub 2}C and CeIr{sub 2}Ge{sub 2}, do not appear to exhibit bulk magnetic ordering down to 2 K. The alloys, Ce{sub 2}Pd{sub 2}In and Ce{sub 2}Cu{sub 2}In, order magnetically below 4 and 6 K, respectively, and a marginal change in the Pd(Cu)/In composition does not significantly influence the ordering temperatures. (orig.).

  3. EPR study of concentration dependence in Ce, Ce : La and Ce:Y doped SrF2

    NARCIS (Netherlands)

    Dankert, O.; Vainchtein, David; Datema, H.C.; den Hartog, Hendrik

    1995-01-01

    Experimental results of an EPR-study of the concentration dependence of the doubly integrated intensity and linewidth of the signals associated with tetragonal Ce3+-F--dipoles in Sr1-xCexF2+x, Sr-1-0.005-x Ce0.005LaxF2+0.005+x and Sr-1-0.005-x Ce0.005YxF2+0.005+x are presented. Both show a nonlinear

  4. Coherence Kondo gap in CeNiSn and CeRhSb

    International Nuclear Information System (INIS)

    Takabatake, T.; Nakamoto, G.; Tanaka, H.; Bando, Y.; Fujii, H.; Nishigori, S.; Goshima, H.; Suzuki, T.; Fujita, T.; Oguro, I.; Hiraoka, T.; Malik, S.K.

    1994-01-01

    CeNiSn and CeRhSb are Kondo-lattice compounds showing the behavior of a small-gap semiconductor at temperatures below 7 K. We review and discuss the magnetic, transport and specific-heat measurements performed on single crystals of CeNiSn and polycrystals of CeRhSb. Prerequisites for gap formation are deduced from the effects of substitution and application of a magnetic field and pressure on the gapped state. ((orig.))

  5. The role of Ce(III) in BZ oscillating reactions

    Science.gov (United States)

    Nogueira, Paulo A.; Varela, Hamilton; Faria, Roberto B.

    2012-03-01

    Herein we present results on the oscillatory dynamics in the bromate-oxalic acid-acetone-Ce(III)/Ce(IV) system in batch and also in a CSTR. We show that Ce(III) is the necessary reactant to allow the emergence of oscillations. In batch, oscillations occur with Ce(III) and also with Ce(IV), but no induction period is observed with Ce(III). In a CSTR, no oscillations were found using a freshly prepared Ce(IV), but only when the cerium-containing solution was aged, allowing partial conversion of Ce(IV) to Ce(III) by reaction with acetone.

  6. Adduct formation in Ce(IV) thenolytrifluoroacetonate

    International Nuclear Information System (INIS)

    Anufrieva, S.I.; Polyakova, G.V.; Snezhko, N.I.; Pechurova, N.I.; Martynenko, L.I.; Spitsyn, V.I.

    1982-01-01

    The literature contains no information on adduct formation in Ce(IV) β-diketonates with additional ligands. Since tetrakis-β-diketonates of Ce(IV) have four six-membered chelate rings, we can suppose that the introduction of an additional monodentate or bidentate ligand into the coordination sphere of Ce(IV) β-diketonates would lead to an increase in the coordination number (CN) of the Ce(IV) to nine or ten. The possibility of realization of such a high CN for Ce(IV) has not been proved; a study of adduct formation by Ce(IV) tetrakis-β-diketonates is thus of theoretical interest. Such an investigation might also be of practical interest, because the introduction of an additional ligand into the coordination sphere of a rare-earth β-diketonate usually increases the solubility of the β-diketonate in nonpolar solvents and increases the volatility of the compound; such a modification of the properties is important for various practical purposes. The aim of our work was to study the possibility of separating solid adducts of Ce(IV) tetrakis-thenoyltrifluoroacetonate with certain oxygen-containing and nitrogen-containing donor monodentate and bidentate ligands, and also to investigate their properties. As the β-diketone we used thenoyltrifluoroacetone (HTTFA), since in a parallel investigation it was found that Ce(TTFA) 4 has a high oxidation-reduction stability

  7. Unstable magnetic moments in Ce compounds

    International Nuclear Information System (INIS)

    Aarts, J.

    1984-01-01

    The problems which are connected with the appearance or disappearance of local moments in metals are well reflected in the magnetic behaviour of Ce intermetallic compounds. This work describes experiments on two Ce compounds which are typical examples of unstable moment systems. The first of these is CeAl 2 which at low temperatures, shows coexistence of antiferromagnetic order and the Kondo effect. Measurements are presented of the magnetization and the susceptibility in different magnetic field and temperature regions. An analysis of these measurements, using a model for the crystal field effects, shows the agreement between the measurements and the calculations to be reasonably good for CeAl 2 , but this agreement becomes worse upon decreasing Ce concentration. A phenomenological description of the observations is given. The second compound reported on is CeCu 2 Si 2 , the first 'heavy-fermion' superconductor to be investigated. The superconducting state is possibly formed by the quasi-particles of a non-magnetic many body singlet state, and not simply by the (sd) conduction electrons. This being a novel phenomenon, a number of experiments were performed to test this picture and to obtain a detailed description of the behaviour of CeCu 2 Si 2 . Measurements of the Meissner volume, confirmed the superconductivity to be intrinsic. (Auth.)

  8. Chemically abrupt interface between Ce oxide and Fe films

    International Nuclear Information System (INIS)

    Lee, H.G.; Lee, D.; Kim, S.; Kim, S.G.; Hwang, Chanyong

    2005-01-01

    A chemically abrupt Fe/Ce oxide interface can be formed by initial oxidation of an Fe film followed by deposition of Ce metal. Once a Ce oxide layer is formed on top of Fe, it acts a passivation barrier for oxygen diffusion. Further deposition of Ce metal followed by its oxidation preserve the abrupt interface between Ce oxide and Fe films. The Fe and Ce oxidation states have been monitored at each stage using X-ray photoelectron spectroscopy

  9. Pyrazolates advance cerium chemistry: a CeIII/CeIV redox equilibrium with benzoquinone.

    Science.gov (United States)

    Werner, Daniel; Deacon, Glen B; Junk, Peter C; Anwander, Reiner

    2017-05-16

    Two stable cerium(iv) 3,5-dialkylpyrazolate complexes are presented, namely dimeric [Ce(Me 2 pz) 4 ] 2 (Me 2 pz = 3,5-dimethylpyrazolate) and monomeric Ce(tBu 2 pz) 4 (tBu 2 pz = 3,5-di-tert-butylpyrazolate) along with their trivalent counterparts [Ce(Me 2 pz) 3 ] and [Ce(tBu 2 pz) 3 ] 2 . All complexes were obtained from protonolysis reactions employing the silylamide precursors Ce[N(SiHMe 2 ) 2 ] 4 and Ce[N(SiMe 3 ) 2 ] 3 . Treatment of homoleptic Ce IV and Ce III Me 2 pz complexes with 1,4-hydroquinone (H 2 hq) or 1,4-benzoquinone (bq), respectively, ultimately gave the same trimetallic Ce III species via a cerium redox equilibrium. The Ce III complex Ce 3 (Me 2 pz) 5 (pchd) 2 (L) (pchd = 1,4-bis(3,5-dimethylpyrazol-1-yl)cyclohex-2,5-diene-1,4-diolato; L = Me 2 pzH or (thf) 2 ) results from a di-1,4-pyrazolyl attack on pre-coordinated bq. The reduction of bq by [Ce(Me 2 pz) 3 (thf)] 2 , and re-oxidation by the resulting Ce IV species was supported by UV-vis spectroscopic investigations. Comparisons with the redox-innocent complexes [Ln(Me 2 pz) 3 (thf)] 2 (Ln = La and Pr) revealed far less selective reactions with bq, giving hexametallic and octametallic rare-earth metal side products containing 2-Me 2 pz substituted hq ligands.

  10. Feasibility Study of Biopower in East Helena, Montana. A Study Prepared in Partnership with the Environmental Protection Agency for the RE-Powering America's Land Initiative: Siting Renewable Energy on Potentially Contaminated Land and Mine Sites

    Energy Technology Data Exchange (ETDEWEB)

    Moriarty, K.

    2013-02-01

    The U.S. Environmental Protection Agency (EPA) developed the RE-Powering America's Land initiative to reuse contaminated sites for renewable energy generation when aligned with the community's vision for the site. The former American Smelting and Refining Company (Asarco) smelter in East Helena, Montana, was selected for a feasibility study under the initiative. Biomass was chosen as the renewable energy resource based on the wood products industry in the area. Biopower was selected as the technology based on Montana's renewable portfolio standard (RPS) requiring utilities to purchase renewable power.

  11. Radiation streaming with SAM-CE

    International Nuclear Information System (INIS)

    De Gangi, N.; Cohen, M.O.; Waluschka, E.; Steinberg, H.A.

    1980-01-01

    The SAM-CE Monte Carlo code has been employed to calculate doses, due to neutron streaming, on the operating floor and other locations of the Millstone Unit II Nuclear Power Facility. Calculated results were compared against measured doses

  12. (EC+β+) decay of 130Ce

    International Nuclear Information System (INIS)

    Xu Shuwei; Zhang Tianmei; Xie Yuanxiang; Ma Ruichang; Ge Yuanxiu; Guo Yingxiang; Wang Chunfang; Li Zhankui; Guo Bing; Xing Jianping; Guo Tianrui; Zhu Shaofei; Xu Wang; Du Jinzhou

    1996-01-01

    The nuclide 130 Ce was produced by a ( 16 O, 4n) reaction on an enriched 118 Sn target. Reaction products were transported to a shielded location by using a helium-jet tape transport system. A 22.9 min activity in chemically separated cerium sample was identified as 130 Ce. The (EC+β + ) decay scheme of 130 Ce was proposed for the first time. This scheme includes 108 γ-lines, 107 γ-lines among them being new. More than 13 1 + low-lying states of 130 La are populated in the decay of 130 Ce. Two new isomers with half-life of 77±10 ns and 17±5 ns were observed by means of delayed γ-γ coincidence measurements. (orig.). With 5 figs., 3 tabs

  13. Structural and magnetic properties of Ce/Fe and Ce/FeCoV multilayers

    Energy Technology Data Exchange (ETDEWEB)

    Tixier, S; Boeni, P [Paul Scherrer Inst. (PSI), Villigen (Switzerland); Mannix, D; Stirling, W G [Liverpool Univ. (United Kingdom); Lander, G H

    1997-09-01

    Ce/Fe and Ce/FeCoV multilayers have been grown by magnetron sputtering. The interfaces are well defined and the layers are crystalline down to an individual layer thickness of 20 A. Ce/FeCoV multilayers show sharper interfaces than Ce/Fe but some loss of crystallinity is observed. Hysteresis loops obtained by SQUID show different behaviour of the bulk magnetisation as a function of the layer thickness. Fe moments are found by Moessbauer spectroscopy to be perpendicular to the interfaces for multilayers with small periodicity. (author) 2 figs., 2 refs.

  14. Resonant photoemission study of CeRu4Sb12

    International Nuclear Information System (INIS)

    Ishii, Hiroyoshi; Miyahara, Tsuneaki; Takayama, Yasuhiro; Shiozawa, Hidetsugu; Obu, Kenji; Matsuda, Tatsuma D.; Aoki, Yuji; Sugawara, Hitoshi; Sato, Hideyuki

    2005-01-01

    We have measured the Ce 4d-4f and Ce 3d-4f resonant photoemission spectra of CeRu 4 Sb 12 . The Ce 4f spectra show the spectral features corresponding to a weakly hybridized system. The number of 4f electrons is estimated to be ∼1.0

  15. Promoting effect of CeO 2 on cyclohexanol conversion over CeO 2

    Indian Academy of Sciences (India)

    Abstract. CeO2-ZnO materials were prepared by amorphous citrate process and characterized by TGA, XRD, UV-DRS and surface area measurements. TGA showed that the citrate precursors decompose in the range 350-550°C producing CeO2-containing catalytic materials. XRD and DRS results indicated the formation of ...

  16. Fabrication of Nano-CeO2 and Application of Nano-CeO2 in Fe Matrix Composites

    International Nuclear Information System (INIS)

    Tiebao, W.; Chunxiang, C.; Xiaodong, W.; Guobin, L.

    2010-01-01

    It is expatiated that nano-CeO2 is fabricated by the direct sedimentation method. The components and particles diameter of nano-CeO2 powders are analyzed by XRD and SEM . The thermodynamic analysis and acting mechanism of nano-CeO2 with Al in Fe matrix composites are researched, which shows that the reaction is generated between CeO2 and Al in the composite, that is, 3CeO2+4Al - 2Al2O3+3[Ce], which obtains Al2O3 and active [Ce] during the sintering process. The active [Ce] can improve the performance of CeO2/Fe matrix composites. The suitable amount of CeO2 is about 0.05% in CeO2/Fe matrix composites. SEM fracture analysis shows that the toughness sockets in nano-CeO2/Fe matrix composites are more than those in no-added nano-CeO2 composites, which can explain that adding nano-CeO2 into Fe matrix composite, the toughness of the composite is improved significantly. Applied nano-CeO2 to Fe matrix diamond saw blades shows that Fe matrix diamond saw blade is sharper and of longer cutting life than that with no-added nano-CeO2.

  17. Different magnetic behaviour of the Kondo compounds Al3Ce and Al11Ce3

    International Nuclear Information System (INIS)

    Benoit, A.; Flouquet, J.; Palleau, J.; Buevoz, J.L.

    1979-08-01

    Neutron diffraction experiments on the Al 3 Ce and Al 11 Ce 3 compounds have been performed on the multidetector of the I.L.L. high flux reactor. No magnetic structure has been detected on the Al 3 Ce compound down to 20 mK. This confirms the non magnetic ground state of Al 3 Ce. For Al 11 Ce 3 , two magnetic structures have been observed: a ferromagnetic one at 4.2 K and an antiferromagnetic one at 2 K. The antiferromagnetic structure, which corresponds to a propagation vector (0,0,1/3), implies a strong reduction of the magnetic moment of determined sites; this reflects the Kondo character of the compounds

  18. Physico-chemical properties of (U,Ce)O2

    International Nuclear Information System (INIS)

    Yamada, K.; Yamanaka, S.; Katsura, M.

    1998-01-01

    The high-temperature X-ray diffraction analysis of (U,Ce)O 2 with CeO 2 contents ranging from 0 to 20 mol.% CeO 2 was performed to obtain the variation of the linear thermal expansion coefficient with the CeO 2 content. Ultrasonic pulse-echo measurements were also carried out from room temperature to 673 K to estimate the change in the mechanical properties of (U,Ce)O 2 with the CeO 2 content. The variation in the linear thermal expansion coefficient at the low CeO 2 content region is more steep than that expected from the linear thermal expansion coefficient of UO 2 and CeO 2 . The Young's and shear moduli of all (U,Ce)O 2 were found to decrease with rising temperature. This was due to the increase of the bond length accompanied by the thermal expansion. Although the lattice parameter decreased with CeO 2 content, the moduli of (U,Ce)O 2 were found to decrease with increasing CeO 2 content at room temperature. These results show that in the range from 0 to 20 mol.% of CeO 2 , as CeO 2 content increases, the bottom of the potential energy in (U,Ce)O 2 is shallower and broader. (orig.)

  19. Report on the basic survey on promotion of joint project implementation in fiscal 1998. 'Repowering of three gas-based thermal power plants'; 1998 nendo kyodo jisshi nado suishin kiso chosa. Gas base karyoku hatsudensho no repowering (3 plant)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-03-01

    With an objective of reactivating and reduction of emission of greenhouse effect gases, investigations and discussions were given on repowering three thermal power plants in the Federal Republic of Russia. The project on Kirishi Power Station calls for withdrawal of 1800-MW capacity out of the existing generation capacity of 2100 MW, and installation of a combined cycle power plant having an output capacity of 1950 MW. The existing 300-MW capacity will be used mainly for heat supply. At Puskovskaya Power Plant, a combined cycle power plant with a capacity of 1170 MW will be built newly. Iriklinskaya Power Station will have the existing plant removed, where a new combined cycle power plant with a capacity of 2340 MW will be constructed. As a result of the discussions, the cumulative reduction amount of CO2 emission will reach 44.67 million tons, 10.53 million tons, and 89.94 million tons respectively, and the investment return rate before tax will be 11.35%, 11.85% and 11.18% respectively. This project is expected to contribute largely to reduction of CO2 emission, and at the same time strengthen the foundation of the power plant management. (NEDO)

  20. The Fermi surface of CeSb

    International Nuclear Information System (INIS)

    Crabtree, G.W.; Aoki, H.; Joss, W.; Hulliger, F.

    1987-01-01

    This paper uses accurate Fermi surface measurements as a test of hybridization models in CeSb. Detailed measurements of the Fermi surface geometry and effective masses are presented which show a number of unusual properties associated with the magnetic structure and anisotropy. Measurements are compared with predictions of a band structure in which the f-electron is assumed to be local, interacting with the conduction electrons only through anisotropic Coulomb and exchange interactions. This model reproduces all the unusual features observed in the measurements and suggests that hybridization is not essential to describing the electronic properties of CeSb

  1. CeO2-stabilized tetragonal ZrO2 polycrystals (Ce-TZP ceramics)

    International Nuclear Information System (INIS)

    Andrade Nono, M.C. de.

    1990-12-01

    This work presents the development and the characterization of CeO 2 -stabilized tetragonal ZrO 2 polycrystals (Ce-TZP ceramics), since it is considered candidate material for applications as structural high performance ceramics. Sintered ceramics were fabricated from mixtures of powders containing different CeO 2 content prepared by conventional and nonconventional techniques. These powders and their resultant sintered ceramics were specified by chemical and physical characterization, compactation state and mechanical properties. The chemical characteristics were determined by chemical analysis and the physical characteristics were evaluated by phase content, particle and agglomerate size and aspect, and powder porosity. (author)

  2. Production of 139Ce by the 139La(p,n)139Ce reaction

    International Nuclear Information System (INIS)

    Ishioka, Noriko S.; Sekine, Toshiaki; Izumo, Mishiroku; Hashimoto, Kazuyuki; Kobayashi, Katsutoshi; Matsuoka, Hiromitsu

    2002-01-01

    To produce a carrier-free 139 Ce to be used as an efficiency-calibration source for Ge detectors, a target-preparation method and a chemical separation method were studied. It was found that commercially available powders of lanthanum-oxide and lanthanum metal are applicable to a target material in the nuclear reaction 139 La(p,n) 139 Ce. In the separation of 139 Ce from an irradiated lanthanum target, a solvent-extraction method and an ion-exchange method gave final products in good chemical purity. (author)

  3. Microneedle Array Interface to CE on Chip

    NARCIS (Netherlands)

    Lüttge, Regina; Gardeniers, Johannes G.E.; Vrouwe, E.X.; van den Berg, Albert; Northrup, M.A.; Jensen, K.F; Harrison, D.J.

    2003-01-01

    This paper presents a microneedle array sampler interfaced to a capillary electrophoresis (CE) glass chip with integrated conductivity detection electrodes. A solution of alkali ions was electrokinetically loaded through the microneedles onto the chip and separation was demonstrated compared to a

  4. Correlated electronic structure of CeN

    Energy Technology Data Exchange (ETDEWEB)

    Panda, S.K., E-mail: swarup.panda@physics.uu.se [Department of Physics and Astronomy, Uppsala University, P.O. Box 516, SE-751 20 Uppsala (Sweden); Di Marco, I. [Department of Physics and Astronomy, Uppsala University, P.O. Box 516, SE-751 20 Uppsala (Sweden); Delin, A. [Department of Physics and Astronomy, Uppsala University, P.O. Box 516, SE-751 20 Uppsala (Sweden); KTH Royal Institute of Technology, School of Information and Communication Technology, Department of Materials and Nano Physics, Electrum 229, SE-164 40 Kista (Sweden); KTH Royal Institute of Technology, Swedish e-Science Research Center (SeRC), SE-100 44 Stockholm (Sweden); Eriksson, O., E-mail: olle.eriksson@physics.uu.se [Department of Physics and Astronomy, Uppsala University, P.O. Box 516, SE-751 20 Uppsala (Sweden)

    2016-04-15

    Highlights: • The electronic structure of CeN is studied within the GGA+DMFT approach using SPTF and Hubbard I approximation. • 4f spectral functions from SPTF and Hubbard I are coupled to explain the various spectroscopic manifestations of CeN. • The calculated XPS and BIS spectra show good agreement with the corresponding experimental spectra. • The contribution of the various l-states and the importance of cross-sections for the photoemission process are analyzed. - Abstract: We have studied in detail the electronic structure of CeN including spin orbit coupling (SOC) and electron–electron interaction, within the dynamical mean-field theory combined with density-functional theory in generalized gradient approximation (GGA+DMFT). The effective impurity problem has been solved through the spin-polarized T-matrix fluctuation-exchange (SPTF) solver and the Hubbard I approximation (HIA). The calculated l-projected atomic partial densities of states and the converged potential were used to obtain the X-ray-photoemission-spectra (XPS) and Bremstrahlung Isochromat spectra (BIS). Following the spirit of Gunnarsson–Schonhammer model, we have coupled the SPTF and HIA 4f spectral functions to explain the various spectroscopic manifestations of CeN. Our computed spectra in such a coupled scheme explain the experimental data remarkably well, establishing the validity of our theoretical model in analyzing the electronic structure of CeN. The contribution of the various l-states in the total spectra and the importance of cross sections are also analyzed in detail.

  5. Some regularities of Ce(3) and Ce(4) stabilization in their compounds with β-diketones

    International Nuclear Information System (INIS)

    Pechurova, N.I.; Martynenko, L.I.; Snezhko, N.I.; Anufrieva, S.I.

    1985-01-01

    Adduct formation of cerium (3) and cerium (4) β-diketonates (acetylacetonate, benzoylacetonate, dibenzoylmethanate and thenoyltrifluoroacetonate) with oxygen- and nitrogen-donor ligands (Q-α, α'-dipyridyl, o-phenanthroline, trioctylphosphine oxide and triphenylphosphine oxide) is studied. The compounds obtained as a results of the reactions are studied by means of IR-spectroscopic, derivatographic and X-ray phase methods. It is concluded that composition and thermodynamic stability of adducts of Ce(3) tris-β-diketonates are determined by correlation of donor properties of the basis and additional ligand and stability of adducts to oxidation - as well as by their solubility. Introduction of the additional ligand to the system Ce(4)-β-diketones even in the presence of air oxygen stabilizes Ce(3) and destabilizes Ce(4)

  6. Magnetic and electronic properties in CeTSi3 and CeTGe3 (T: transition metal)

    International Nuclear Information System (INIS)

    Shimoda, T.; Okuda, Y.; Takeda, Y.; Ida, Y.; Miyauchi, Y.; Kawai, T.; Fujie, T.; Sugitani, I.; Thamizhavel, A.; Matsuda, T.D.; Haga, Y.; Takeuchi, T.; Nakashima, M.; Settai, R.; Onuki, Y.

    2007-01-01

    We investigated the magnetic properties of CeTSi 3 (T: Ru, Os, Co, Rh, Ir, Pd and Pt) and CeTGe 3 (T: Co, Rh and Ir) by measuring their electrical resistivity and magnetic susceptibility. CeRuSi 3 , CeOsSi 3 and CeCoSi 3 do not order magnetically, with a large Kondo temperature of about 200K. The other compounds order antiferromagnetically, and are very similar to each other in their magnetic and electronic properties, which is related to a large crystalline electric field (CEF) splitting energy of the 4f electron, about 500K in CeIrSi 3

  7. Tuning Ce distribution for high performanced Nd-Ce-Fe-B sintered magnets

    Energy Technology Data Exchange (ETDEWEB)

    Fan, Xiaodong [School of Materials Science and Engineering, Xi’an University of Technology, Xi’an 710048 (China); Key Laboratory of Magnetic Materials and Devices, Ningbo Institute of Material Technology and Engineering, Chinese Academy of Science, Ningbo 315201 (China); Guo, Shuai; Chen, Kan; Chen, Renjie; Lee, Don [Key Laboratory of Magnetic Materials and Devices, Ningbo Institute of Material Technology and Engineering, Chinese Academy of Science, Ningbo 315201 (China); You, Caiyin, E-mail: caiyinyou@xaut.edu.cn [School of Materials Science and Engineering, Xi’an University of Technology, Xi’an 710048 (China); Yan, Aru, E-mail: aruyan@nimte.ac.cn [Key Laboratory of Magnetic Materials and Devices, Ningbo Institute of Material Technology and Engineering, Chinese Academy of Science, Ningbo 315201 (China)

    2016-12-01

    A dual-alloy method was applied to tune the distribution of Ce for enhancing the performance of Nd-Ce-Fe-B sintered magnets with a nominal composition of (Nd{sub 0.75}Ce{sub 0.25}){sub 30.5}Fe{sub bal}Al{sub 0.1}Cu{sub 0.1}B. In comparison to the single alloy of (Nd{sub 0.75}Ce{sub 0.25}){sub 30.5}Fe{sub bal}Al{sub 0.1}Cu{sub 0.1}B, the coercivity was enhanced from 10.3 kOe to 12.1 kOe and the remanence was increased from 13.1 kG to 13.3 kG for the magnets with a dual-alloy method. In addition, the remanence temperature coefficient α and coercivity temperature coefficient β were also slightly improved for the magnet with the dual alloys. The results of microstructure characterizations show the uniform distribution of Ce for the magnet with a single alloy, and the coexistence of the Ce-rich and Ce-lean regions for the magnet with the dual alloys. In combinations with the nucleation of reversal domains and magnetic recoil curves, the property enhancement of magnets with a dual-alloy method was well explained. - Highlights: • Improved magnetic properties were obtained in dual-alloy magnet. • This is due to the tuning of Ce distribution and the change in microstructure. • The magnetic hardening effect can be observed in dual-alloy magnet.

  8. Inhibition of human carboxylesterases hCE1 and hiCE by cholinesterase inhibitors.

    Science.gov (United States)

    Tsurkan, Lyudmila G; Hatfield, M Jason; Edwards, Carol C; Hyatt, Janice L; Potter, Philip M

    2013-03-25

    Carboxylesterases (CEs) are ubiquitously expressed proteins that are responsible for the detoxification of xenobiotics. They tend to be expressed in tissues likely to be exposed to such agents (e.g., lung and gut epithelia, liver) and can hydrolyze numerous agents, including many clinically used drugs. Due to the considerable structural similarity between cholinesterases (ChE) and CEs, we have assessed the ability of a series of ChE inhibitors to modulate the activity of the human liver (hCE1) and the human intestinal CE (hiCE) isoforms. We observed inhibition of hCE1 and hiCE by carbamate-containing small molecules, including those used for the treatment of Alzheimer's disease. For example, rivastigmine resulted in greater than 95% inhibition of hiCE that was irreversible under the conditions used. Hence, the administration of esterified drugs, in combination with these carbamates, may inadvertently result in decreased hydrolysis of the former, thereby limiting their efficacy. Therefore drug:drug interactions should be carefully evaluated in individuals receiving ChE inhibitors. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  9. Facile hydrothermal synthesis of CeO 2 nanopebbles

    Indian Academy of Sciences (India)

    Cerium oxide (CeO2) nanopebbles have been synthesized using a facile hydrothermal method. X-ray diffraction pattern (XRD) and transmission electron microscopy analyses confirm the presence of CeO2 nanopebbles. XRD shows the formation of cubic fluorite CeO2 and the average particle size estimated from the ...

  10. Cerium intermetallics CeTX. Review III

    Energy Technology Data Exchange (ETDEWEB)

    Poettgen, Rainer; Janka, Oliver [Muenster Univ. (Germany). Inst. fuer Anorganische und Analytische Chemie; Chevalier, Bernard [Bordeaux Univ., Pessac (France). Inst. de Chimie de la Matiere Condensee de Bordeaux

    2016-05-01

    The structure-property relationships of CeTX intermetallics with structures other than the ZrNiAl and TiNiSi type are systematically reviewed. These CeTX phases form with electron-poor and electron-rich transition metals (T) and X = Mg, Zn, Cd, Hg, Al, Ga, In, Tl, Si, Ge, Sn, Pb, P, As, Sb, and Bi. The review focusses on the crystal chemistry, the chemical bonding peculiarities, and the magnetic and transport properties. Furthermore {sup 119}Sn Moessbauer spectroscopic data, high-pressure studies, hydrogenation reactions and the formation of solid solutions are reviewed. This paper is the third of a series of four reviews on equiatomic intermetallic cerium compound [Part I: R. Poettgen, B. Chevalier, Z. Naturforsch. 2015, 70b, 289; Part II: R. Poettgen, B. Chevalier, Z. Naturforsch. 2015, 70b, 695].

  11. 78 FR 75557 - CE FLNG, LLC, CE Pipeline, LLC; Notice of Intent To Prepare an Environmental Impact Statement for...

    Science.gov (United States)

    2013-12-12

    ... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket No. PF13-11-000] CE FLNG, LLC, CE Pipeline, LLC; Notice of Intent To Prepare an Environmental Impact Statement for the Planned CE FLNG Project, Request for Comments on Environmental Issues, and Notice of Public Scoping Meeting The staff of the Federal Energy Regulatory Commission ...

  12. Itinerant f-electron behavior in Ce and U compounds

    International Nuclear Information System (INIS)

    Crabtree, G.W.

    1985-04-01

    The experimentally observed Fermi surface properties in URh 3 , UIr 3 , UGe 3 , CeSn 3 , CeB 6 , U 3 As 4 , U 3 P 4 , and CeSb are reviewed. For the compounds with no magnetic order, band structure models of the Fermi surface geometry are confirmed and f-ligand hybridization is found to be dominant. For CeB 6 , U 3 As 4 , and U 3 P 4 the experiments show that both local moments and f hybridization are important. In CeSb new data can be explained by a purely local model with no f-hybridization

  13. Thermodynamic stability studies of Ce-Sb compounds with Fe

    Science.gov (United States)

    Xie, Yi; Zhang, Jinsuo; Benson, Michael T.; Mariani, Robert D.

    2018-02-01

    Lanthanide fission products can migrate to the fuel periphery and react with cladding, causing fuel-cladding chemical interaction (FCCI). Adding a fuel additive dopant, such as Sb, can bind lanthanide, such as Ce, into metallic compounds and thus prevent migration. The present study focuses on the thermodynamic stability of Ce-Sb compounds when in contact with the major cladding constituent Fe by conducting diffusion couple tests. Ce-Sb compounds have shown high thermodynamic stability as they did not react with Fe. When Fe-Sb compounds contacted with Ce, Sb was separated out of Fe-Sb compounds and formed the more stable Ce-Sb compounds.

  14. Ce(III)/Ce(IV) in methanesulfonic acid as the positive half cell of a redox flow battery

    International Nuclear Information System (INIS)

    Leung, P.K.; Ponce de Leon, C.; Low, C.T.J.; Walsh, F.C.

    2011-01-01

    The characteristics of the Ce(III)/Ce(IV) redox couple in methanesulfonic acid were studied at a platinum disk electrode (0.125 cm 2 ) over a wide range of electrolyte compositions and temperatures: cerium (III) methanesulfonate (0.1-1.2 mol dm -3 ), methanesulfonic acid (0.1-5.0 mol dm -3 ) and electrolyte temperatures (295-333 K). The cyclic voltammetry experiments indicated that the diffusion coefficient of Ce(III) ions was 0.5 x 10 -6 cm 2 s -1 and that the electrochemical kinetics for the oxidation of Ce(III) and the reduction of Ce(IV) was slow. The reversibility of the redox reaction depended on the electrolyte composition and improved at higher electrolyte temperatures. At higher methanesulfonic acid concentrations, the degree of oxygen evolution decreased by up to 50% when the acid concentration increased from 2 to 5 mol dm -3 . The oxidation of Ce(III) and reduction of Ce(IV) were also investigated during a constant current batch electrolysis in a parallel plate zinc-cerium flow cell with a 3-dimensional platinised titanium mesh electrode. The current efficiencies over 4.5 h of the process Ce(III) to Ce(IV) and 3.3 h electrolysis of the reverse reaction Ce(IV) to Ce(III) were 94.0 and 97.6%, respectively. With a 2-dimensional, planar platinised titanium electrode (9 cm 2 area), the redox reaction of the Ce(III)/Ce(IV) system was under mass-transport control, while the reaction on the 3-dimensional mesh electrode was initially under charge-transfer control but became mass-transport controlled after 2.5-3 h of electrolysis. The effect of the side reactions (hydrogen and oxygen evolution) on the current efficiencies and the conversion of Ce(III) and Ce(IV) are discussed.

  15. Feasibility Study of Economics and Performance of Biopower at the Chanute Air Force Base in Rantoul, Illinois. A Study Prepared in Partnership with the Environmental Protection Agency for the RE-Powering America's Land Initiative: Siting Renewable Energy on Potentially Contaminated Land and Mine Sites

    Energy Technology Data Exchange (ETDEWEB)

    Scarlata, C.; Mosey, G.

    2013-05-01

    The U.S. Environmental Protection Agency (EPA), in accordance with the RE-Powering America's Land initiative, selected the Former Chanute Air Force Base site in Rantoul, Illinois, for a feasibility study of renewable energy production. The National Renewable Energy Laboratory (NREL) was contacted to provide technical assistance for this project. The purpose of this study was to assess the site for a possible biopower system installation and estimate the cost, performance, and impacts of different biopower options.

  16. Feasibility Study of Economics and Performance of a Hydroelectric Installation at the Jeddo Mine Drainage Tunnel. A Study Prepared in Partnership with the Environmental Protection Agency for the RE-Powering America's Land Initiative: Siting Renewable Energy on Potentially Contaminated Land and Mine Sites

    Energy Technology Data Exchange (ETDEWEB)

    Roberts, J. O.; Mosey, G.

    2013-02-01

    The U.S. Environmental Protection Agency (EPA), in accordance with the RE-Powering America's Land initiative, selected the Jeddo Tunnel discharge site for a feasibility study of renewable energy potential. The purpose of this report is to assess technical and economic viability of the site for hydroelectric and geothermal energy production. In addition, the report outlines financing options that could assist in the implementation of a system.

  17. Transient analysis capabilities at ABB-CE

    International Nuclear Information System (INIS)

    Kling, C.L.

    1992-01-01

    The transient capabilities at ABB-Combustion Engineering (ABB-CE) Nuclear Power are a function of the computer hardware and related network used, the computer software that has evolved over the years, and the commercial technical exchange agreements with other related organizations and customers. ABB-CEA is changing from a mainframe/personal computer network to a distributed workstation/personal computer local area network. The paper discusses computer hardware, mainframe computing, personal computers, mainframe/personal computer networks, workstations, transient analysis computer software, design/operation transient analysis codes, safety (licensed) analysis codes, cooperation with ABB-Atom, and customer support

  18. Synthesis and characterization of Ce doped MFI zeolite

    International Nuclear Information System (INIS)

    Kalita, Banani; Talukdar, Anup K.

    2012-01-01

    Highlights: ► Cerium was incorporated into the tetrahedral position of MFI zeolite structure. ► Unit cell volume increases with an increase of Ce content in the framework of MFI. ► A band at 310 nm in the UV–vis spectra indicates Ce incorporation in MFI structure. ► The mass loss (%) in the region 373–423 K decreases with increase of Ce in MFI. - Abstract: Ce doped MFI (mobil five) zeolites with different Si to (Ce + Al) and different Ce to Al ratios were synthesized by a hydrothermal synthesis method. All the samples were characterized by different techniques such as X-ray diffraction, Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), UV–vis diffuse reflectance spectroscopy (DRS) and scanning electron microscopy (SEM). The results showed that almost pure MFI phase was obtained in all cases with incorporation of cerium metal into the framework. The increase in unit cell parameters observed with an increase in Ce content is indicative of incorporation of Ce into the framework structure of microporous material MFI. Corroboration of the framework incorporation of Ce into the MFI zeolite structure was also obtained from the UV–vis DRS spectra by the presence of an absorption band at 280 nm. TGA and SEM of the samples provide complementary evidence for Ce incorporation into the framework MFI structure.

  19. Synthesis of CeS and interactions with molten metals

    International Nuclear Information System (INIS)

    Krikorian, O.H.; Curtis, P.G.

    1988-01-01

    Hot-pressed and sintered discs of single-phase CeS were tested for interaction with molten aluminium, uranium, and iron to determine the conditions under which reaction first begins and the nature of the reaction. Aluminium begins to react with CeS at ∼ 1190 K, slowly dissolving cerium and forming a thin layer of Ce 3 S 4 at the reaction interface. At 1363 K, aluminium wets and spreads over the CeS surface and dissolves ∼ 01 at% Ce. Ce 3 Al 11 precipitates out in the aluminium phase on cooldown. Uranium does not react with CeS at 1673 K, but at 1873 K it wets and spreads on CeS and dissolves ∼ 100 atom ppm S, which precipitates out as US on cooldown. Iron wets CeS at 1873 K and 1973 K but does not spread or interact. Because of the desirable containment characteristics of CeS and similar sulfides for molten metals, we recommend their use in a number of applications. (author)

  20. Oxidation of Ce(III) in Foam Decontaminant by Ozone

    International Nuclear Information System (INIS)

    Jung, Chong Hun; Yoon, I. H.; Choi, W. K.; Moon, J. K.; Yang, H. B.; Lee, J. S.

    2016-01-01

    A nanoparticle-based foam decontaminant is composed of a surfactant and nanoparticles for the generation and maintenance of foam, and a chemical decontamination agent made of Ce(IV) dissolved in nitric acid. Ce(IV) will be reduced to Ce(III) through the decontamination process. Oxidizing cerium(III) can be reused as a decontamination agent, Ce(IV). Oxidation treatment technology by ozone uses its strong oxidizing power. It can be regarded as an environmentally friendly process, because ozone cannot be stored and transported like other industrial gases (because it quickly decays into diatomic oxygen) and must therefore be produced on site, and used ozone can decompose immediately. The ozonation treatment of Ce(III) in foam decontaminant containing a surfactant is necessary for the effective regeneration of Ce(III). Thus, the present study was undertaken to determine the optimal conditions for ozonation treatment in the regeneration of Ce(III) into Ce(IV) in the nanoparticle-based foam decontaminant containing surfactant. This study was undertaken to determine the optimal conditions for ozonation treatment in the regeneration of Ce(III) to Ce(IV) in nanoparticle-based foam decontaminant containing a TBS surfactant. The oxidation conversion rate of Ce(III) was increased with an increase in the flow rate of the gas mixture and ozone injection amount. The oxidation time required for the 100% oxidation conversion of Ce(III) to Ce(IV) at a specific ozone injection amount can be predicted from these experimental data

  1. Oxidation of Ce(III) in Foam Decontaminant by Ozone

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Chong Hun; Yoon, I. H.; Choi, W. K.; Moon, J. K.; Yang, H. B. [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Lee, J. S. [Gachon University, Seongnam (Korea, Republic of)

    2016-10-15

    A nanoparticle-based foam decontaminant is composed of a surfactant and nanoparticles for the generation and maintenance of foam, and a chemical decontamination agent made of Ce(IV) dissolved in nitric acid. Ce(IV) will be reduced to Ce(III) through the decontamination process. Oxidizing cerium(III) can be reused as a decontamination agent, Ce(IV). Oxidation treatment technology by ozone uses its strong oxidizing power. It can be regarded as an environmentally friendly process, because ozone cannot be stored and transported like other industrial gases (because it quickly decays into diatomic oxygen) and must therefore be produced on site, and used ozone can decompose immediately. The ozonation treatment of Ce(III) in foam decontaminant containing a surfactant is necessary for the effective regeneration of Ce(III). Thus, the present study was undertaken to determine the optimal conditions for ozonation treatment in the regeneration of Ce(III) into Ce(IV) in the nanoparticle-based foam decontaminant containing surfactant. This study was undertaken to determine the optimal conditions for ozonation treatment in the regeneration of Ce(III) to Ce(IV) in nanoparticle-based foam decontaminant containing a TBS surfactant. The oxidation conversion rate of Ce(III) was increased with an increase in the flow rate of the gas mixture and ozone injection amount. The oxidation time required for the 100% oxidation conversion of Ce(III) to Ce(IV) at a specific ozone injection amount can be predicted from these experimental data.

  2. Calculations of coupled channels for the reaction 142Ce(α,α1)142 Ce*

    International Nuclear Information System (INIS)

    Appoloni, C.R.; Lepine, A.

    1980-01-01

    Elastic and inelastic angular distribution were made for α particles of 18 Mev in 142 Ce. It was determined the angular distributions corresponding to the various states of the target nucleus. The angular distributions corresponding to the first five states were analyzed within the framework of the Anarhmonic vibrational and symmetric rotational models. (A.C.A.S.) [pt

  3. Band structures in near spherical 138Ce

    Science.gov (United States)

    Bhattacharjee, T.; Chanda, S.; Bhattacharyya, S.; Basu, S. K.; Bhowmik, R. K.; Das, J. J.; Pramanik, U. Datta; Ghugre, S. S.; Madhavan, N.; Mukherjee, A.; Mukherjee, G.; Muralithar, S.; Singh, R. P.

    2009-06-01

    The high spin states of N=80138Ce have been populated in the fusion evaporation reaction 130Te( 12C, 4n) 138Ce at E=65 MeV. The γ transitions belonging to various band structures were detected and characterized using an array of five Clover Germanium detectors. The level scheme has been established up to a maximum spin and excitation energy of 23 ℏ and 9511.3 keV, respectively, by including 53 new transitions. The negative parity ΔI=1 band, developed on the 6536.3 keV 15 level, has been conjectured to be a magnetic rotation band following a semiclassical analysis and comparing the systematics of similar bands in the neighboring nuclei. The said band is proposed to have a four quasiparticle configuration of [πgh]⊗[. Other band structures are interpreted in terms of multi-quasiparticle configurations, based on Total Routhian Surface (TRS) calculations. For the low and medium spin states, a shell model calculation using a realistic two body interaction has been performed using the code OXBASH.

  4. Peculiarities of the intermediate valence state of Ce in CeM2Si2 (M = Fe, Co, Ni) compounds

    International Nuclear Information System (INIS)

    Koterlyn, M.; Shcherba, I.; Yasnitskii, R.; Koterlyn, G.

    2007-01-01

    The results of thermoelectric power and the electrical resistivity measurements connected with the intermediate valence (IV) of Ce are presented for the compounds CeM 2 Si 2 (M = Fe, Co, Ni) in the temperature range of 4-800 K. It is shown that CeM 2 Si 2 are Kondo-lattices with the coherence scale T coh ∼ 60-80 K and the so-called single-site Kondo temperature T K ∼ 10 3 K. On the example of CeNi 2 Si 2 we have studied the changes in the structure of density of f states (f-DOS) near the Fermi energy caused by atomic substitutions. The results of structural, transport, magnetic, and Ce L III X-ray absorption spectra measurements in the series Ce 1-x La x Ni 2 Si 2 (0 ≤ x ≤ 0.6), Ce(Ni 1-y Cu y ) 2 Si 2 (0 ≤ y ≤ 0.6) and CeNi 2 (Si 1-z Ge z ) 2 (0 ≤ z ≤ 0.5) are presented. We found that the IV state of Ce in the CeM 2 Si 2 is an evidence of possible opening a wide pseudogap Δ ∼ kT K within the f-DOS structure slightly above the Fermi energy

  5. CEF-scheme of a semimetal Ce3Sn7

    International Nuclear Information System (INIS)

    Okuda, Yusuke; Yamamoto, Takeshi; Honda, Daisuke; Shishido, Hiroaki; Galatanu, Andrei; Haga, Yoshinori; Matsuda, Tatsuma D.; Takeuchi, Tetsuya; Kindo, Koichi; Sugiyama, Kiyohiro; Settai, Rikio; O-bar nuki, Yoshichika

    2005-01-01

    We measured the magnetic susceptibility and magnetization of an antiferromagnet Ce 3 Sn 7 with the orthorhombic crystal structure. The experimental data are found to be well explained on the basis of the crystalline electric field (CEF) 4f-scheme under the assumption that two Ce atoms in the 2(a) site possess a magnetic moment of 0.36μ B /Ce and one Ce atom in the 4(i) site possesses no magnetic moment as in a valence fluctuating compound CeSn 3 , which was previously proposed by Bonnet et al. Furthermore, we carried out the de Haas-van Alphen experiment. The detected Fermi surfaces are many in number but are extremely small in volume, indicating that Ce 3 Sn 7 is a semimetal

  6. A pressure study of CePt{sub 3}B

    Energy Technology Data Exchange (ETDEWEB)

    Rauch, Daniela; Suellow, Stefan [Institute of Condensed Matter Physics, University of Technology Braunschweig, Braunschweig (Germany); Hartwig, Steffen [Institute of Condensed Matter Physics, University of Technology Braunschweig, Braunschweig (Germany); BENSC, Helmholtz Zentrum Berlin, Berlin (Germany); Hidaka, Hiroyuki; Yamazaki, Seigo; Amitsuka, Hiroshi [Department of Physics, Hokkaido University, Sapporo (Japan); Bauer, Ernst [Institute of Solid State Physics, Vienna University of Technology, Vienna (Austria)

    2013-07-01

    CePt{sub 3}B is isostructural to the non-centro symmetric heavy-fermion superconductor CePt{sub 3}Si. In contrast to the latter system, CePt{sub 3}B exhibits a complex magnetically ordered state at low temperatures, with an antiferromagnetic phase below T{sub N}=7.8 K and a weakly ferromagnetic transition below T{sub C}∼5 K. CePt{sub 3}B can be understand as a low pressure variant of CePt{sub 3}Si. Here we report a study of CePt{sub 3}B by means of high pressure magnetization measurements, this way in particular accessing the pressure evolution of the ferromagnetic transition temperature T{sub C}. From our investigation up to about 40 kbar we observe an almost constant transition temperature T{sub C} with pressure. This behavior we discuss in the context of alloying studies on this material.

  7. Distribution and Translocation of 141Ce (III) in Horseradish

    Science.gov (United States)

    Guo, Xiaoshan; Zhou, Qing; Lu, Tianhong; Fang, Min; Huang, Xiaohua

    2007-01-01

    Background and Aims Rare earth elements (REEs) are used in agriculture and a large amount of them contaminate the environment and enter foods. The distribution and translocation of 141Ce (III) in horseradish was investigated in order to help understand the biochemical behaviour and toxic mechanism of REEs in plants. Method The distribution and translocation of 141Ce (III) in horseradish were investigated using autoradiography, liquid scintillation counting (LSC) and electron microscopic autoradiography (EMARG) techniques. The contents of 141Ce (III) and nutrient elements were analysed using an inductively coupled plasma-atomic emission spectrometer (ICP-AES). Results The results from autoradiography and LSC indicated that 141Ce (III) could be absorbed by horseradish and transferred from the leaf to the leaf-stalk and then to the root. The content of 141Ce (III) in different parts of horseradish was as follows: root > leaf-stalk > leaf. The uptake rates of 141Ce (III) in horseradish changed with the different organs and time. The content of 141Ce (III) in developing leaves was greater than that in mature leaves. The results from EMARG indicated that 141Ce (III) could penetrate through the cell membrane and enter the mesophyll cells, being present in both extra- and intra-cellular deposits. The contents of macronutrients in horseradish were decreased by 141Ce (III) treatment. Conclusions 141Ce (III) can be absorbed and transferred between organs of horseradish with time, and the distribution was found to be different at different growth stages. 141Ce (III) can enter the mesophyll cells via apoplast and symplast channels or via plasmodesmata. 141Ce (III) can disturb the metabolism of macronutrients in horseradish. PMID:17921527

  8. Synthesis and structural characterization of Ce-doped bismuth titanate

    International Nuclear Information System (INIS)

    Pavlovic, Nikolina; Srdic, Vladimir V.

    2009-01-01

    Ce-modified bismuth titanate nanopowders Bi 4-x Ce x Ti 3 O 12 (x ≤ 1) have been synthesized using a coprecipitation method. DTA/TG, FTIR, XRD, SEM/EDS and BET methods were used in order to investigate the effect of Ce-substitution on the structure, morphology and sinterability of the obtained powders. The phase structure investigation revealed that after calcinations at 600 deg. C powder without Ce addition exhibited pure bismuth titanate phase; however, powders with Ce (x = 0.25, 0.5 and 0.75) had bismuth titanate pyrochlore phase as the second phase. The strongest effect of Ce addition on the structure was noted for the powder with the highest amount of Ce (x = 1) having a cubic pyrochlore structure. The presence of pure pyrochlore phase was explained by its stabilization due to the incorporation of cerium ions in titanate structure. Ce-modified bismuth titanate ceramic had a density over 95% of theoretical density and the fracture in transgranular manner most probably due to preferable distribution of Ce in boundary region

  9. Inverted opal luminescent Ce-doped silica glasses

    Directory of Open Access Journals (Sweden)

    R. Scotti

    2006-01-01

    Full Text Available Inverted opal Ce-doped silica glasses (Ce : Si molar ratio 1 ⋅ 10−3 were prepared by a sol-gel method using opals of latex microspheres as templates. The rare earth is homogeneously dispersed in silica host matrix, as evidenced by the absence of segregated CeO2, instead present in monolithic Ce-doped SG with the same cerium content. This suggests that the nanometric dimensions of bridges and junctions of the host matrix in the inverted opal structures favor the RE distribution avoiding the possible segregation of CeO2.

  10. CeO2-ZrO2 ceramic compounds

    International Nuclear Information System (INIS)

    Melo, F.C.L.; Cairo, C.A.C.; Devezas, T.C.; Nono, M.C.A.

    1988-01-01

    In order to study the mechanical properties of tetragonal polycrystal zirconia stabilized with ceria various powder compositions with different CeO 2 content were made. Modulus of rupture for those compounds was measured. Tetragonal retained phase was determined for samples of CeO 2 -ZrO 2 ceramics with and without superficial mechanical treatment. The experimental results allowed us to evaluate the effects of CeO 2 content and sintering temperature in the mechanical properties and tetragonal transformed phase (t→ m) in ceramics of CeO 2 -ZrO 2 systems. (author) [pt

  11. The highest spin discrete levels in 131,132Ce

    International Nuclear Information System (INIS)

    Paul, E S; Choy, P T W; Andreoiu, C; Boston, A J; Evans, A O; Fox, C; Gros, S; Nolan, P J; Rainovski, G; Sampson, J A; Scraggs, H C; Walker, A; Appelbe, D E; Joss, D T; Simpson, J; Gizon, J; Astier, A; Buforn, N; Prevost, A; Redon, N; Stezowski, O; Nyako, B M; Sohler, D; Timar, J; Zolnai, L; Bazzacco, D; Lunardi, S; Petrache, C M; Bednarczyk, P; Curien, D; Kintz, N; Ragnarsson, I

    2006-01-01

    The three superdeformed (SD) bands in 132 Ce and the two SD bands in 131 Ce have been extended to higher spin following experiments with the EUROBALL IV spectrometer. The two SD bands in 131 Ce have been linked together. However, despite the relatively high population intensity of the bands (up to 5% of the respective channel), it has not been possible to unambiguously link any of the five SD bands into the low-spin, normally deformed structures of 131,132 Ce

  12. Comparison of Spectral and Scintillation Properties of LuAP:Ce and LuAP:Ce,Sc Single Crystals

    Science.gov (United States)

    Petrosyan, Ashot G.; Derdzyan, Marina; Ovanesyan, Karine; Shirinyan, Grigori; Lecoq, Paul; Auffray, Etiennette; Kronberger, Matthias; Frisch, Benjamin; Pedrini, Christian; Dujardin, Christophe

    2009-10-01

    Scintillation properties of LuAP:Ce and LuAP:Ce,Sc crystal series were studied under excitation by gamma-rays from a 137Cs source. Both series demonstrated comparable optical quality in terms of underlying absorption at 260 nm, slope of the optical edge and transmission in the range of emission. The light yield of LuAP:Ce crystals measured in 0.2 cm times 0.2 cm times 0.8 cm pixels increases linearly with the Ce concentration reaching at 0.58 at. % 6448 plusmn 322 ph/MeV and 9911 plusmn 496 ph/MeV in the long and in the short directions respectively (the light yield ratio is 65%) and shows no sign of light saturation. The energy resolution is found to depend, among other factors, on the uniformity of Ce concentration within the pixels and is improved to 7.1 plusmn 0.4% (I = 0.2 cm), 9.5 plusmn 0.5% (I = 0.8 cm). Intentional co-doping with Sc + ions was tested and resulted in increase of the Ce distribution coefficient to about 0.3. This enabled to increase the concentration of Ce in LuAP:Ce,Sc crystals up to 0.7 at. %, while conserving high optical quality. In contrast to LuAP:Ce, the light yield in LuAP:Ce,Sc crystals does not increase with Ce concentration, the photo peak being gradually suppressed. The involved mechanisms are discussed basing on measurements of the unit cell volumes, Ce concentration uniformity, x-ray rocking spectra, absorption spectra of pure and variously doped LuAP crystals, and emission spectra under different excitations.

  13. C-E productivity improvement program

    International Nuclear Information System (INIS)

    Chiu, C.; Ching, B.; Van Haltern, M.L.

    1984-01-01

    This paper describes the C-E Productivity Improvement Program (CEPIP), which is a computer algorithm for heat rate monitoring and diagnostics for a nuclear power plant. CEPIP uses the pattern recognition technique to identify cause(s) of heat rate degradation. The benefits of such an automated program to the plant performance engineer include early identification of the degrading component(s), provision of necessary economic information (cost of energy loss) to the performance engineer so that he can decide when to repair the degrading components, and identification of operator actions resulting in heat rate degradation (such as closing the valve on the live steam extraction line for the second stage of reheat). In summary, CEPIP improves the overall plant performance by increasing the capacity factor. CEPIP was developed to meet the growing needs of the utilities for an automated performance program. The diagnostic capability has been verified by plant data

  14. Radiative β-decay in 141Ce

    International Nuclear Information System (INIS)

    Rao, K.S.G.; Sanjeeviah, H.

    1982-01-01

    The spectral distribution of the continuous gamma radiation accompanying non-unique first forbidden β-decay of 32 d 141 Ce has been measured in the energy range 200-560 keV with a 4.5 cm x 5.08 cm NaI(Tl) scintillation spectrometer. The source electrons were eliminated using an electromagnet. The raw spectrum was corrected for pile-up, finite energy resolution, Compton electron distribution and geometrical γ-detection efficiency using the method of Liden and Starfelt. The corrected distribution is compared with the direct and detour theories of Lewis and Ford, and Ford and Martin, respectively. Total disagreement between experiment and theory was observed over the entire region of the investigated spectrum. In the energy region from 200 to 350 keV, however, the measured spectrum lies between the direct and detour theories. (orig.)

  15. Dependence of the Ce(iii)/Ce(iv) ratio on intracellular localization in ceria nanoparticles internalized by human cells

    KAUST Repository

    Ferraro, Daniela; Tredici, Ilenia G.; Ghigna, Paolo; Castillio-Michel, Hiram; Falqui, Andrea; Di Benedetto, Cristiano; Alberti, Giancarla; Ricci, Vittorio; Anselmi-Tamburini, Umberto; Sommi, Patrizia

    2017-01-01

    CeO2 nanoparticles (CNPs) have been investigated as promising antioxidant agents with significant activity in the therapy of diseases involving free radicals or oxidative stress. However, the exact mechanism responsible for CNP activity has not been completely elucidated. In particular, in situ evidence of modification of the oxidative state of CNPs in human cells and their evolution during cell internalization and subsequent intracellular distribution has never been presented. In this study we investigated modification of the Ce(iii)/Ce(iv) ratio following internalization in human cells by X-ray absorption near edge spectroscopy (XANES). From this analysis on cell pellets, we observed that CNPs incubated for 24 h showed a significant increase in Ce(iii). By coupling on individual cells synchrotron micro-X-ray fluorescence (μXRF) with micro-XANES (μXANES) we demonstrated that the Ce(iii)/Ce(iv) ratio is also dependent on CNP intracellular localization. The regions with the highest CNP concentrations, suggested to be endolysosomes by transmission electron microscopy, were characterized by Ce atoms in the Ce(iv) oxidation state, while a higher Ce(iii) content was observed in regions surrounding these areas. These observations suggest that the interaction of CNPs with cells involves a complex mechanism in which different cellular areas play different roles.

  16. Dependence of the Ce(iii)/Ce(iv) ratio on intracellular localization in ceria nanoparticles internalized by human cells

    KAUST Repository

    Ferraro, Daniela

    2017-01-09

    CeO2 nanoparticles (CNPs) have been investigated as promising antioxidant agents with significant activity in the therapy of diseases involving free radicals or oxidative stress. However, the exact mechanism responsible for CNP activity has not been completely elucidated. In particular, in situ evidence of modification of the oxidative state of CNPs in human cells and their evolution during cell internalization and subsequent intracellular distribution has never been presented. In this study we investigated modification of the Ce(iii)/Ce(iv) ratio following internalization in human cells by X-ray absorption near edge spectroscopy (XANES). From this analysis on cell pellets, we observed that CNPs incubated for 24 h showed a significant increase in Ce(iii). By coupling on individual cells synchrotron micro-X-ray fluorescence (μXRF) with micro-XANES (μXANES) we demonstrated that the Ce(iii)/Ce(iv) ratio is also dependent on CNP intracellular localization. The regions with the highest CNP concentrations, suggested to be endolysosomes by transmission electron microscopy, were characterized by Ce atoms in the Ce(iv) oxidation state, while a higher Ce(iii) content was observed in regions surrounding these areas. These observations suggest that the interaction of CNPs with cells involves a complex mechanism in which different cellular areas play different roles.

  17. Dopant concentration dependence of radiation-induced positive hysteresis of Ce:GSO and Ce:GSOZ

    International Nuclear Information System (INIS)

    Yanagida, Takayuki; Fujimoto, Yutaka; Watanabe, Kenichi

    2014-01-01

    Positive hysteresis and radiation tolerance to high-dose radiation exposure were investigated for Ce 0.5, 1, and 1.5%-doped Gd 2 SiO 5 (GSO) and for Zr co-doped GSO with the same Ce concentrations (GSOZ). When they were irradiated by 200–800 Gy 60 Co in 200 Gy steps, all Ce-doped GSO samples exhibited light yield enhancement (positive hysteresis). On the other hand, the light yield of GSOZ decreased greatly. Ce 0.5%-doped GSO showed the highest positive hysteresis, with ∼20% light yield enhancement. When the Ce concentration was increased, the positive hysteresis became weaker. - Highlights: • Positive hysteresis Ce 0.5, 1, and 1.5% doped GSO and GSOZ are studied. • Ce 0.5, 1, and 1.5% doped GSO show the positive hysteresis by 2–8 M rad 60 Co irradiation. • Ce 0.5, 1, and 1.5% doped GSOZ do not show the positive hysteresis. • By Zn co-doping, radiation tolerance of GSO becomes weaker. • By dense Ce doping, radiation tolerance of GSO and GSOZ are improved

  18. Traducerea: între ce se poate traduce și ce trebuie tradus

    Directory of Open Access Journals (Sweden)

    Magda Jeanrenaud

    2016-02-01

    Full Text Available Pornind de la o tulburătoare interpretare a lui Jacques Derrida, studiul de față își propune să investigheze și încearcă să explice blocajul ce intervine în versiunile englezești, franceze și românești (semnate de Antoine Berman, Alexis Nouss, Steven Rendall, Catrinel Pleșu etc. ale celebrului text al lui Walter Benjamin, Die Aufgabe des Übersetzers, atunci cînd traducătorii transpun în cele trei limbi țintă cele două citate cuprinse în acesta: un citat din Mallarmé, lăsat netradus de Benjamin însuși, și un altul, din Pannwitz. Într-un fel sau altul, ambele citate au o formă discursivă ce lasă să se întrevadă o sintaxă ce se abate deliberat de la normă, ca și cum ar fi deja niște „traduceri”. Analiza mai pune în evidență și comportamentul (cumva o dominantă a psihologiei traducătorilor? celor ce au transpus textul benjaminian, comportament marcat de obsesia lizibilității văzută ca o trăsătură congenitală a oricărei traduceri, chiar și atunci cînd textul original nu tinde spre aceasta. De unde și dilema, dureroasă, legată de spinoasa chestiune a intenționalității textului (nu doar de tradus...

  19. Evidence of complex magnetism in CePt3C

    International Nuclear Information System (INIS)

    Vejpravova, J.; Prokleska, J.; Danis, S.; Uhlirova, K.; Sechovsky, V.

    2006-01-01

    CePt 3 C has been synthesized and studied by powder X-ray diffraction (at RT), specific heat, resistivity and magnetization measurements at temperatures from RT down to 0.4K and in magnetic fields up to 10T. A possible scenario for the ground state of CePt 3 C based on the observed phenomena is proposed

  20. 32 CFR Appendix B to Part 247 - CE Publications

    Science.gov (United States)

    2010-07-01

    ... dining at a restaurant or attending a musical performance) of a commercial organization whose primary... potentially become the CE contractor. Upon evaluation of the competing proposals by the Source Selection Advisory Committee (SSAC) and selection of a winner by the selecting official, the CE contract shall be...

  1. Ce que nous faisons | CRDI - Centre de recherches pour le ...

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

    Le CRDI appuie des travaux de recherche dans les pays en voie de développement en vue de produire un changement réel et durable. Ce savoir peut servir d'outil pour résoudre des problèmes mondiaux urgents. Nous partageons ce savoir avec les autres en :

  2. Facile hydrothermal synthesis of CeO2 nanopebbles

    Indian Academy of Sciences (India)

    Administrator

    However, to the best of our knowledge the reports on the synthesis of CeO2 ... The base pressure of the XAS chamber was in the range of 10–8 Pa. A Shimadzu ... scopy was investigated to confirm the crystalline quality of CeO2 nanopebbles.

  3. Ferroelectric relaxor Ba(TiCe)O3

    International Nuclear Information System (INIS)

    Chen Ang; Zhi Jing; Yu Zhi

    2002-01-01

    The dielectric behaviour of Ba(Ti 1-y Ce y )O 3 solid solutions (y=0-0.3) has been studied. A small amount of Ce doping (y=0.02) has weak influence on the dielectric behaviour of Ba(Ti 1-y Ce y )O 3 . With increasing Ce concentration, three phase transitions of pure BaTiO 3 are pinched into one rounded dielectric peak with frequency dispersion, and the relaxation time follows the Vogel-Fulcher relation. The evolution from a normal ferroelectric to a ferroelectric relaxor is emphasized. High strains (S=∼0.1-0.19%) with a small hysteresis under ac fields are obtained in ferroelectric relaxors Ba(Ti 1-y Ce y )O 3 . The physical mechanism of the relaxation process, the pinching effect of the phase transitions and their influence on the ferroelectric and electrostrictive behaviour are discussed. (author)

  4. Photodynamic Processes in Fluoride Crystals Doped with Ce3+

    Directory of Open Access Journals (Sweden)

    Pavlov V.V.

    2015-01-01

    Full Text Available Integrated studies of photoelectric phenomena and their associated photodynamic processes in LiCaAlF6, LiLuF4, LiYF4, LiY0,5Lu0,5F4, SrAlF5 crystals doped with Ce3+ ions have been carried out using the combination of the methods of optical and dielectric spectroscopy. The numerical values of the basic parameters of photodynamic processes and their spectral dependence in 240 – 310 nm spectral range are evaluated. It has been shown that the most probable process, which leads to the photoionization of Ce3+ ions in LiYxLu1-xF4:Ce3+ (x=0; 0,5; 1 and LiCaAlF6:Ce3+ crystals, is excited-state absorption to the states of mixed configurations of Ce3+ ions localized near/in the conduction band of crystal.

  5. CE APPROVAL IN ELECTRICAL HOUSEHOLD APPLIANCES AND A CASE STUDY

    Directory of Open Access Journals (Sweden)

    Nazmi EKREN

    2009-01-01

    Full Text Available Due to the reason for rapidly developing technology, increasing competition medium, and awareness of the consumers, nowadays, the exigency of production with good quality has gained more and more significance. Certification of the quality and safety of the products to the consumers is compulsory in terms of producers. There are some documents to certify safety of the products. One of them is CE certificate. In this paper, basic information about CE mark is given and CE standards and tests required for electrical household appliances are mentioned. As an application, one of an electrical household appliance, toaster grill is treated and examined. To obtain CE certificate for toaster grill, required tests are made according to EN60335-2-9 and CE certificate is obtained.

  6. Archiver ce qui aurait pu avoir lieu

    Directory of Open Access Journals (Sweden)

    Stefanie Baumann

    2009-12-01

    Full Text Available L’Atlas Group, un projet de l’artiste libanais Walid Raad, est « dédié à la recherche et la compilation de documents sur l’histoire contemporaine libanaise. L’Atlas Group produit, localise, conserve et étudie des documents visuels, sonores, textuels et autres, qui mettent en lumière l’histoire actuelle du Liban. »Ce projet est ainsi présenté comme une fondation qui génère des archives historiques et qui collecte des traces relevant de la guerre au Liban afin de les mettre à disposition aux chercheurs. Mais, les matériaux sont produits par l’artiste : l’archive est imaginaire, les documents et récits sont inventés, ainsi que le Docteur Fakhouhi, le personnage principal, présenté comme étant « le plus renommé des historiens au Liban ». Le spectateur se trouve alors devant un scénario très étrange dans lequel sont détournées les notions de document (qui peut désormais être aussi bien trouvé que produit et d’histoire (car les situations décrites sont considérées comme « ayant très bien pu avoir eu lieu », l’Atlas Group  les traite comme de véritables événement historiques et qui déplace, mine de rien, tout un dispositif. Au sein de ce projet, la frontière entre fiction et documentaire est complètement estompée : le geste de l’artiste (qui, lui, se présente comme une institution, un « Groupe », interroge ainsi le statut même d’auteur vise à la déplacer pour poser des questions relatives aux représentations possibles de l’histoire, aux personnes aptes à se charger de son écriture et à l’opération historiographique.

  7. Superconductivity and anomalous normal state in the CePd2Si2/CeNi2Ge2 system

    International Nuclear Information System (INIS)

    Grosche, F.M.; Lister, S.J.S.; Carter, F.V.; Saxena, S.S.; Haselwimmer, R.K.W.; Mathur, N.D.; Julian, S.R.; Lonzarich, G.G.

    1997-01-01

    The unconventional nonmagnetic metal CeNi 2 Ge 2 is characterised at ambient pressure by temperature dependences of the specific heat and of the resistivity which deviate strongly from standard Fermi-liquid predictions and are reminiscent of the behaviour observed in its sibling system CePd 2 Si 2 above the critical pressure at which magnetic order is suppressed. We have explored the CePd 2 Si 2 /CeNi 2 Ge 2 phase diagram in a series of resistivity measurements under high hydrostatic pressure, p. At p>15 kbar, a new superconducting transition appears below 220 mK in CeNi 2 Ge 2 and shifts to higher temperatures with increasing pressure, reaching ∝400 mK at p∝26 kbar. (orig.)

  8. Tetragonal zirconia ceramics in Zr O2-Ce O2 system (Ce-TZP): preparation, characterization and mechanical properties

    International Nuclear Information System (INIS)

    Andrade Nono, M.C. de.

    1992-01-01

    This paper describes and discusses the results achieved in a study about Ce-TZP ceramics prepared from conventional powder mixtures of Zr O 2 and Ce O 2 (with composition in the range of 8 to 16 mol% Ce O 2 ). Physical and chemical characteristics were related with the powder compaction behavior and with the sintering state. The sintered ceramics showed a level of high porosity (≅ 4%), mainly due to the fairly adequate powder characteristics and compaction. The crystalline phases were analysed from X-rays diffraction data and showed that these ceramics can present tetragonal-to-monoclinic stress induced transformation. The bending strength, fracture toughness and Vickers hardness results were influenced by Ce O 2 content microstructure and sintering temperature. These Ce-TZP ceramics showed mechanical strength results comparable to those published in the international literature. (author)

  9. Fermi surface study of CeSb

    International Nuclear Information System (INIS)

    Aoki, H.; Crabtree, G.W.; Joss, W.; Hulliger, F.

    1984-09-01

    A Fermi surface study of the ferromagnetic phase of CeSb is presented. The γ frequency branches arising from the electron surfaces at the X points, three separate frequency branches from the hole surfaces at the GAMMA point and the low frequency branch α have been observed. The effective mass ratios are low and range from approx. 0.2 for the α branch to approx. 1.0 for the high frequency branch of γ. The low effective mass ratios suggest that the admixture of the conduction states with the f state is small. We have observed a drastic change in the appearance of the dHvA signal at the phase transition between the ferromagnetic and lower field antiferromagnetic phases: The low frequency α oscillation suddenly disappears as the crystal enters the antiferromagnetic phase. By utilizing the change in the signal appearance, the transition field strength has been measured as a function of the field direction. The present experimental results, particularly the origin of the α oscillation, are discussed in the light of the p-f mixing theory and recent band structure calculations based on localized f orbitals

  10. Fermi surface study of CeSb

    International Nuclear Information System (INIS)

    Aoki, H.; Crabtree, G.; Joss, W.; Hulliger, F.

    1985-01-01

    A Fermi surface study of the ferromagnetic phase of CeSb is presented. The γ frequency branches arising from the electron surfaces at the X points, three separate frequency branches from the hole surfaces at the GAMMA point, and the low-frequency branch α have been observed. The effective mass ratios are low and range from approx.0.2 for the α branch to approx.1.0 for the high-frequency branch of γ. The low effective mass ratios suggest that the admixture of the conduction states with the f state is small. We have observed a drastic change in the appearance of the de Haas--van Alpen signal at the phase transition between the ferromagnetic and lower field antiferromagnetic phases: the low-frequency α oscillation suddenly disappears as the crystal enters the antiferromagnetic phase. By utilizing the change in the signal appearance, the transition field strength has been measured as a function of the field direction. The present experimental results particularly the origin of the α oscillation, are discussed in the light of the p-f mixing theory and recent band-structure calculations based on localized f orbitals

  11. Recent approaches in sensitive enantioseparations by CE.

    Science.gov (United States)

    Sánchez-Hernández, Laura; Castro-Puyana, María; Marina, María Luisa; Crego, Antonio L

    2012-01-01

    The latest strategies and instrumental improvements for enhancing the detection sensitivity in chiral analysis by CE are reviewed in this work. Following the previous reviews by García-Ruiz et al. (Electrophoresis 2006, 27, 195-212) and Sánchez-Hernández et al. (Electrophoresis 2008, 29, 237-251; Electrophoresis 2010, 31, 28-43), this review includes those papers that were published during the period from June 2009 to May 2011. These works describe the use of offline and online sample treatment techniques, online sample preconcentration techniques based on electrophoretic principles, and alternative detection systems to UV-Vis to increase the detection sensitivity. The application of the above-mentioned strategies, either alone or combined, to improve the sensitivity in the enantiomeric analysis of a broad range of samples, such as pharmaceutical, biological, food and environmental samples, enables to decrease the limits of detection up to 10⁻¹² M. The use of microchips to achieve sensitive chiral separations is also discussed. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Mechanochemical and combustion synthesis of CeB{sub 6}

    Energy Technology Data Exchange (ETDEWEB)

    Akguen, Baris [Roketsan Missiles Inc., Ankara (Turkey); Sevinc, Naci; Topkaya, Yavuz [Middle East Technical Univ., Ankara (Turkey). Dept. of Metallurgical and Materials Engineerung; Camurlu, H. Erdem [Akdeniz Univ., Antalya (Turkey). Dept. of Mechanical Engineering

    2013-04-15

    CeB{sub 6} powder was prepared via combustion synthesis (CS) and mechanochemical processing (MCP) methods starting from CeO{sub 2}, B{sub 2}O{sub 3} and Mg powder mixtures. In CS, reactant mixtures were ignited in a preheated pot furnace under argon atmosphere. Products contained CeB{sub 6}, MgO and Mg{sub 3}B{sub 2}O{sub 6}, as revealed by X-ray diffraction analysis. After leaching in 1 M HCl for 15h, MgO was removed but Mg{sub 3}B{sub 2}O{sub 6} could not be removed from the products. Ball milling of products in ethanol prior to leaching made the removal of Mg{sub 3}B{sub 2}O{sub 6} possible by leaching. Yield of CeB{sub 6} was 68.6% in CS. MCP was performed in a stainless steel vial with a planetary ball mill at 300 rpm for 30h. MCP products contained CeB{sub 6}, MgO and small amount of Fe. Leaching in 1 M HCl for 30min was sufficient to remove MgO. Yield of CeB{sub 6} was 84.4% in MCP. According to scanning electron microscopy examinations, particles of CeB6 prepared by CS and MCP had submicrometer size. Average particle sizes were determined as 290nm and 240nm, respectively.

  13. The formation of intermetallic compounds during interdiffusion of Mg–Al/Mg–Ce diffusion couples

    International Nuclear Information System (INIS)

    Dai, Jiahong; Jiang, Bin; Li, Xin; Yang, Qingshan; Dong, Hanwu; Xia, Xiangsheng; Pan, Fusheng

    2015-01-01

    Graphical abstract: Al–Ce intermetallic compounds (IMCs) formed in Mg–Al/Mg–Ce diffusion couples. During the whole diffusion process, Al was the dominant diffusing species, and it substituted for Mg atoms of the Mg–Ce substrate. Five Al–Ce IMCs of Al 4 Ce, Al 11 Ce 3 , Al 3 Ce, Al 2 Ce, and AlCe were formed via the reaction of Al and Ce. - Highlights: • Al–Ce IMCs formation in the Mg–Al/Mg–Ce diffusion couples was studied. • Formation of Al 4 Ce as the first phase was rationalized using the Gibbs free energy. • The activation energy for the growth of the diffusion reaction zones was 36.6 kJ/mol. - Abstract: The formation of Al–Ce intermetallic compounds (IMCs) during interdiffusion of Mg–Al/Mg–Ce diffusion couples prepared by solid–liquid contact method was investigated at 623 K, 648 K and 673 K for 24 h, 48 h and 72 h, respectively. During the whole diffusion process, Al was the dominant diffusing species, and it substituted for Mg of the Mg–Ce substrate. Five Al–Ce IMCs of Al 4 Ce, Al 11 Ce 3 , Al 3 Ce, Al 2 Ce and AlCe were formed via the reaction of Al and Ce. The formation of Al 4 Ce as the first kind of IMC was rationalized on the basis of an effective Gibbs free energy model. The activation energy for the growth of the total diffusion reaction layer was 36.6 kJ/mol

  14. Properties and practical application of thin CeOx films

    Directory of Open Access Journals (Sweden)

    Maksimchuk N. V.

    2010-10-01

    Full Text Available The properties of CeOx films produced by various methods have been investigated. According to the comparative analisys “metallic mirror oxidation” method allows to produce films with significantly better characteristics than the «explosive evaporation» method. Though the latter method yields higher photosensitivity of CeOx films and structures on their base. In the process the optimal value of the substrate temperature was determined. Obtained data expand the CeOx application potential in microelectronic sensor sphere.

  15. Biological reduction-deposition and luminescent properties of nanostructured CePO{sub 4}@NaCe(SO{sub 4}){sub 2}(H{sub 2}O) and CePO{sub 4}

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Xiaoniu [School of Materials Science and Engineering, Southeast University, Nanjing 211189 (China); Research Institute of Green Construction Materials, Southeast University, Nanjing 211189 (China); Qian, Chunxiang, E-mail: cxqian@seu.edu.cn [School of Materials Science and Engineering, Southeast University, Nanjing 211189 (China); Research Institute of Green Construction Materials, Southeast University, Nanjing 211189 (China)

    2016-03-01

    Nano-sized CePO{sub 4}@NaCe(SO{sub 4}){sub 2}(H{sub 2}O) and CePO{sub 4} with hexagonal phase have been prepared by simply varying the reactant P/Ce molar ratio in bacterial liquid. The phase composition of two samples was checked via Fourier transform infrared spectroscopy (FTIR), energy dispersive analysis of X-rays (EDS) and X-ray diffraction (XRD) analyses, displaying the presence of CePO{sub 4}@NaCe(SO{sub 4}){sub 2}(H{sub 2}O) and CePO{sub 4} with average crystallite size are 32.34 and 15.61 nm, respectively. The scanning electron microscopy (SEM) images show that nano-clusters and sphere-like in shape with a narrow diameter distribution were observed in two samples. The transmission electron microscopy (TEM) photographs further indicate obtained CePO{sub 4}@NaCe(SO{sub 4}){sub 2}(H{sub 2}O) and CePO{sub 4} nanoparticles correspond to nanosheets and nanorods, respectively. The emission spectra of CePO{sub 4}@NaCe(SO{sub 4}){sub 2}(H{sub 2}O) and CePO{sub 4} display a broad band of 300–380 nm range with the strongest emission at 342 nm in the violet region. - Highlights: • A new method was found to synthesize CePO{sub 4}@NaCe(SO{sub 4}){sub 2}(H{sub 2}O) and CePO{sub 4} nanoparticles. • CePO{sub 4}@NaCe(SO{sub 4}){sub 2}(H{sub 2}O) nanoparticles have good luminescent properties. • Size and luminescent properties of two samples have been studied and compared.

  16. HumanViCe: Host ceRNA network in virus infected cells in human

    Directory of Open Access Journals (Sweden)

    Suman eGhosal

    2014-07-01

    Full Text Available Host-virus interaction via host cellular components has been an important field of research in recent times. RNA interference mediated by short interfering RNAs and microRNAs (miRNA, is a widespread anti-viral defence strategy. Importantly, viruses also encode their own miRNAs. In recent times miRNAs were identified as key players in host-virus interaction. Furthermore, viruses were shown to exploit the host miRNA networks to suite their own need. The complex cross-talk between host and viral miRNAs and their cellular and viral targets forms the environment for viral pathogenesis. Apart from protein-coding mRNAs, non-coding RNAs may also be targeted by host or viral miRNAs in virus infected cells, and viruses can exploit the host miRNA mediated gene regulatory network via the competing endogenous RNA effect. A recent report showed that viral U-rich non-coding RNAs called HSUR, expressed in primate virus herpesvirus saimiri (HVS infected T cells, were able to bind to three host miRNAs, causing significant alteration in cellular level for one of the miRNAs. We have predicted protein coding and non protein-coding targets for viral and human miRNAs in virus infected cells. We identified viral miRNA targets within host non-coding RNA loci from AGO interacting regions in three different virus infected cells. Gene ontology (GO and pathway enrichment analysis of the genes comprising the ceRNA networks in the virus infected cells revealed enrichment of key cellular signalling pathways related to cell fate decisions and gene transcription, like Notch and Wnt signalling pathways, as well as pathways related to viral entry, replication and virulence. We identified a vast number of non-coding transcripts playing as potential ceRNAs to the immune response associated genes; e.g. APOBEC family genes, in some virus infected cells. All these information are compiled in HumanViCe, a comprehensive database that provides the potential ceRNA networks in virus

  17. Feasibility Study of Economics and Performance of Solar Photovoltaics at the Brisbane Baylands Brownfield Site in Brisbane, California. A Study Prepared in Partnership with the Environmental Protection Agency for the RE-Powering America's Land Initiative: Siting Renewable Energy on Potentially Contaminated Land and Mine Sites

    Energy Technology Data Exchange (ETDEWEB)

    Salasovich, J.; Geiger, J.; Healey, V.; Mosey, G.

    2013-04-01

    The U.S. Environmental Protection Agency (EPA), in accordance with the RE-Powering America's Land initiative, selected the Brisbane Baylands site in Brisbane, California, for a feasibility study of renewable energy production. The National Renewable Energy Laboratory (NREL) provided technical assistance for this project. The purpose of this report is to assess the site for a possible photovoltaic (PV) system installation and estimate the cost, performance, and site impacts of different PV options. In addition, the report recommends financing options that could assist in the implementation of a PV system at the site.

  18. Feasibility Study of Economics and Performance of Solar Photovoltaics at the Ft. Hood Military Base Outside Killeen, Texas. A Study Prepared in Partnership with the Environmental Protection Agency for the RE-Powering America's Land Initiative: Siting Renewable Energy on Potentially Contaminated Land and Mine Sites

    Energy Technology Data Exchange (ETDEWEB)

    Geiger, J.; Lisell, L.; Mosey, G.

    2013-10-01

    The U.S. Environmental Protection Agency (EPA), in accordance with the RE-Powering America's Land initiative through the Region 6 contract, selected Ft. Hood Army Base in Killeen, Texas, for a feasibility study of renewable energy production. The National Renewable Energy Laboratory (NREL) provided technical assistance for this project. The purpose of this study is to assess the site for possible photovoltaic (PV) system installations and estimate the cost, performance, and site impacts of different PV options. In addition, the report recommends financing options that could assist in the implementation of a PV system at the site.

  19. Feasibility Study of Economics and Performance of Solar Photovoltaics at the Price Landfill Site in Pleasantville, New Jersey. A Study Prepared in Partnership with the Environmental Protection Agency for the RE-Powering America's Land Initiative: Siting Renewable Energy on Potentially Contaminated Land and Mine Sites

    Energy Technology Data Exchange (ETDEWEB)

    Salasovich, J.; Geiger, J.; Mosey, G.; Healey, V.

    2013-05-01

    The U.S. Environmental Protection Agency (EPA), in accordance with the RE-Powering America's Land initiative, selected the Price Landfill site in Pleasantville, New Jersey, for a feasibility study of renewable energy production. The National Renewable Energy Laboratory (NREL) provided technical assistance for this project. The purpose of this report is to assess the site for a possible photovoltaic (PV) system installation and estimate the cost, performance, and site impacts of different PV options. In addition, the report recommends financing options that could assist in the implementation of a PV system at the site. This study did not assess environmental conditions at the site.

  20. Feasibility Study of Economics and Performance of Solar Photovoltaics at the Kolthoff Landfill in Cleveland, Ohio. A Study Prepared in Partnership with the Environmental Protection Agency for the RE-Powering America's Land Initiative: Siting Renewable Energy on Potentially Contaminated Land and Mine Sites

    Energy Technology Data Exchange (ETDEWEB)

    Salasovich, J.; Geiger, J.; Mosey, G.; Healey, V.

    2013-06-01

    The U.S. Environmental Protection Agency (EPA), Region 5, in accordance with the RE-Powering America's Land initiative, selected the Kolthoff Landfill site in Cleveland, Ohio, for a feasibility study of renewable energy production. The National Renewable Energy Laboratory (NREL) provided technical assistance for this project. The purpose of this report is to assess the site for a possible photovoltaic (PV) system installation and estimate the cost, performance, and site impacts of different PV options. In addition, the report recommends financing options that could assist in the implementation of a PV system at the site.

  1. Feasibility Study of Economics and Performance of Geothermal Power Generation at the Lakeview Uranium Mill Site in Lakeview, Oregon. A Study Prepared in Partnership with the Environmental Protection Agency for the RE-Powering America's Land Initiative: Siting Renewable Energy on Potentially Contaminated Land and Mine Sites

    Energy Technology Data Exchange (ETDEWEB)

    Hillesheim, M.; Mosey, G.

    2013-11-01

    The U.S. Environmental Protection Agency (EPA), in accordance with the RE-Powering America's Land initiative, selected the Lakeview Uranium Mill site in Lakeview, Oregon, for a feasibility study of renewable energy production. The EPA contracted with the National Renewable Energy Laboratory (NREL) to provide technical assistance for the project. The purpose of this report is to describe an assessment of the site for possible development of a geothermal power generation facility and to estimate the cost, performance, and site impacts for the facility. In addition, the report recommends development pathways that could assist in the implementation of a geothermal power system at the site.

  2. Feasibility Study of Economics and Performance of Solar Photovoltaics at the TechCity East Campus Resource Conservation and Recovery Act Site in Kingston, New York. A Study Prepared in Partnership with the Environmental Protection Agency for the RE-Powering America's Land Initiative: Siting Renewable Energy on Potentially Contaminated Land and Mine Sites

    Energy Technology Data Exchange (ETDEWEB)

    Salasovich, James [National Renewable Energy Lab. (NREL), Golden, CO (United States); Geiger, Jesse W. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Mosey, Gail [National Renewable Energy Lab. (NREL), Golden, CO (United States); Healey, Victoria [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2014-01-01

    The U.S. Environmental Protection Agency (EPA), in accordance with the RE-Powering America's Land initiative, selected the TechCity East Campus site in Kingston, New York, for a feasibility study of renewable energy production. The National Renewable Energy Laboratory (NREL) provided technical assistance for this project. The purpose of this study is to assess the site for a possible photovoltaic (PV) system installation and estimate the cost, performance, and site impacts of different PV options. In addition, the report recommends financing options that could assist in the implementation of a PV system at the site.

  3. Feasibility Study of Economics and Performance of Solar Photovoltaics at the Former Fort Ord Army Base Site in Marina, California. A Study Prepared in Partnership with the Environmental Protection Agency for the RE-Powering America's Land Initiative: Siting Renewable Energy on Potentially Contaminated Land and Mine Sites

    Energy Technology Data Exchange (ETDEWEB)

    Stoltenberg, B.; Konz, C.; Mosey, G.

    2013-05-01

    The U.S. Environmental Protection Agency (EPA), in accordance with the RE-Powering America's Land initiative, selected the Former Fort Ord Army Base (FOAB) site in Marina, California, for a feasibility study of renewable energy production. The National Renewable Energy Laboratory (NREL) provided technical assistance for this project. The purpose of this report is to assess the site for a possible photovoltaic (PV) system installation and estimate the cost, performance, and site impacts of different PV options. In addition, the report recommends financing options that could assist in the implementation of a PV system at the site.

  4. Feasibility Study of Economics and Performance of Solar Photovoltaics at the Standard Chlorine of Delaware Superfund Site in Delaware City, Delaware. A Study Prepared in Partnership with the Environmental Protection Agency for the RE-Powering America's Land Initiative: Siting Renewable Energy on Potentially Contaminated Land and Mine Sites

    Energy Technology Data Exchange (ETDEWEB)

    Salasovich, J.; Geiger, J.; Mosey, G.; Healey, V.

    2013-06-01

    The U.S. Environmental Protection Agency (EPA), in accordance with the RE-Powering America's Land initiative, selected the Standard Chlorine of Delaware site in Delaware City, Delaware, for a feasibility study of renewable energy production. The National Renewable Energy Laboratory (NREL) provided technical assistance for this project. The purpose of this report is to assess the site for a possible photovoltaic (PV) system installation and estimate the cost, performance, and site impacts of different PV options. In addition, the report recommends financing options that could assist in the implementation of a PV system at the site.

  5. Feasibility Study of Economics and Performance of Solar Photovoltaics at the Crazy Horse Landfill Site in Salinas, California. A Study Prepared in Partnership with the Environmental Protection Agency for the RE-Powering America's Land Initiative: Siting Renewable Energy on Potentially Contaminated Land and Mine Sites

    Energy Technology Data Exchange (ETDEWEB)

    Stoltenberg, B.; Konz, C.; Mosey, G.

    2013-03-01

    The U.S. Environmental Protection Agency (EPA), in accordance with the RE-Powering America's Land initiative, selected the Crazy Horse Landfill site in Salinas, California, for a feasibility study of renewable energy production. The National Renewable Energy Laboratory (NREL) was contacted to provide technical assistance for this project. The purpose of this report is to assess the site for a possible photovoltaic (PV) system installation and estimate the cost, performance, operation and maintenance requirements, and site impacts of different PV options. In addition, the report recommends financing options that could assist in the implementation of a PV system at the site.

  6. Feasibility Study of Economics and Performance of Solar Photovoltaics at the Sky Park Landfill Site in Eau Claire, Wisconsin. A Study Prepared in Partnership with the Environmental Protection Agency for the RE-Powering America's Land Initiative: Siting Renewable Energy on Potentially Contaminated Land and Mine Sites

    Energy Technology Data Exchange (ETDEWEB)

    Simon, J.; Mosey, G.

    2013-01-01

    The U.S. Environmental Protection Agency (EPA), in accordance with the RE-Powering America's Land initiative, selected the Sky Park Landfill site in Eau Claire, Wisconsin, for a feasibility study of renewable energy production. The National Renewable Energy Laboratory (NREL) provided technical assistance for this project. The purpose of this report is to assess the site for a possible photovoltaic (PV) system installation and estimate the cost, performance, and site impacts of different PV options. In addition, the report recommends financing options that could assist in the implementation of a PV system at the site.

  7. Feasibility Study of Economics and Performance of Solar Photovoltaics at the Kerr McGee Site in Columbus, Mississippi. A Study Prepared in Partnership with the Environmental Protection Agency for the RE-Powering America's Land Initiative: Siting Renewable Energy on Potentially Contaminated Land and Mine Sites

    Energy Technology Data Exchange (ETDEWEB)

    Simon, J.; Mosey, G.

    2013-01-01

    The U.S. Environmental Protection Agency (EPA), in accordance with the RE-Powering America's Land initiative, selected the Kerr McGee site in Columbus, Mississippi, for a feasibility study of renewable energy production. The National Renewable Energy Laboratory (NREL) provided technical assistance for this project. The purpose of this report is to assess the site for a possible photovoltaic (PV) system installation and estimate the cost, performance, and site impacts of different PV options. In addition, the report recommends financing options that could assist in the implementation of a PV system at the site.

  8. Feasibility Study of Economics and Performance of Solar Photovoltaics at the Tronox Facility in Savannah, Georgia. A Study Prepared in Partnership with the Environmental Protection Agency for the RE-Powering America's Land Initiative: Siting Renewable Energy on Potentially Contaminated Land and Mine Sites

    Energy Technology Data Exchange (ETDEWEB)

    Kiatreungwattana, K.; Geiger, J.; Healey, V.; Mosey, G.

    2013-03-01

    The U.S. Environmental Protection Agency (EPA), in accordance with the RE-Powering America's Land initiative, selected the Tronox Facility site in Savannah, Georgia, for a feasibility study of renewable energy production. The National Renewable Energy Laboratory (NREL) provided technical assistance for this project. The purpose of this report is to assess the site for a possible photovoltaic (PV) system installation and estimate the cost, performance, and site impacts of different PV options. In addition, the report recommends financing options that could assist in the implementation of a PV system at the site.

  9. Feasibility Study of Economics and Performance of Solar Photovoltaics at the Chino Mine in Silver City, New Mexico. A Study Prepared in Partnership with the Environmental Protection Agency for the RE-Powering America's Land Initiative: Siting Renewable Energy on Potentially Contaminated Land and Mine Sites

    Energy Technology Data Exchange (ETDEWEB)

    Kiatreungwattana, K.; Geiger, J.; Healey, V.; Mosey, G.

    2013-04-01

    The U.S. Environmental Protection Agency (EPA), in accordance with the RE-Powering America's Land initiative, selected the Chino Mine site in Silver City, New Mexico, for a feasibility study of renewable energy production. The National Renewable Energy Laboratory (NREL) provided technical assistance for this project. The purpose of this report is to assess the site for a possible photovoltaic (PV) system installation and estimate the cost, performance, and site impacts of different PV options. In addition, the report recommends financing options that could assist in the implementation of a PV system at the site.

  10. Feasibility Study of Economics and Performance of Solar Photovoltaics at the Former Bethlehem Steel Plant Brownfield Site in Lackawanna, New York. A Study Prepared in Partnership with the Environmental Protection Agency for the RE-Powering America's Land Initiative: Siting Renewable Energy on Potentially Contaminated Land and Mine Sites

    Energy Technology Data Exchange (ETDEWEB)

    Salasovich, J.; Geiger, J.; Mosey, G.; Healey, V.

    2013-04-01

    The U.S. Environmental Protection Agency (EPA), in accordance with the RE-Powering America's Land initiative, selected the Former Bethlehem Steel Plant site in Lackawanna, New York, for a feasibility study of renewable energy production. The National Renewable Energy Laboratory (NREL) provided technical assistance for this project. The purpose of this report is to assess the site for a possible photovoltaic (PV) system installation and estimate the cost, performance, and site impacts of different PV options. In addition, the report recommends financing options that could assist in the implementation of a PV system at the site.

  11. Feasibility Study of Economics and Performance of Solar Photovoltaics at the Peru Mill Industrial Park in the City of Deming, New Mexico. A Study Prepared in Partnership with the Environmental Protection Agency for the RE-Powering America's Land Initiative: Siting Renewable Energy on Potentially Contaminated Land and Mine Sites

    Energy Technology Data Exchange (ETDEWEB)

    Kiatreungwattana, K.; Geiger, J.; Healey, V.; Mosey, G.

    2013-04-01

    The U.S. Environmental Protection Agency (EPA), in accordance with the RE-Powering America's Land initiative, selected the Peru Mill Industrial Park site in the City of Deming, New Mexico, for a feasibility study of renewable energy production. The National Renewable Energy Laboratory (NREL) provided technical assistance for this project. The purpose of this report is to assess the site for a possible photovoltaic (PV) system installation and estimate the cost, performance, and site impacts of different PV options. In addition, the report recommends financing options that could assist in the implementation of a PV system at the site.

  12. Feasibility Study of Anaerobic Digestion of Food Waste in St. Bernard, Louisiana. A Study Prepared in Partnership with the Environmental Protection Agency for the RE-Powering America's Land Initiative: Siting Renewable Energy on Potentially Contaminated Land and Mine Sites

    Energy Technology Data Exchange (ETDEWEB)

    Moriarty, K.

    2013-01-01

    The U.S. Environmental Protection Agency (EPA) developed the RE-Powering America's Land initiative to re-use contaminated sites for renewable energy generation when aligned with the community's vision for the site. The former Kaiser Aluminum Landfill in St. Bernard Parish, Louisiana, was selected for a feasibility study under the program. Preliminary work focused on selecting a biomass feedstock. Discussions with area experts, universities, and the project team identified food wastes as the feedstock and anaerobic digestion (AD) as the technology.

  13. Feasibility Study of Economics and Performance of Biomass Power Generation at the Former Farmland Industries Site in Lawrence, Kansas. A Study Prepared in Partnership with the Environmental Protection Agency for the RE-Powering America's Land Initiative: Siting Renewable Energy on Potentially Contaminated Land and Mine Sites

    Energy Technology Data Exchange (ETDEWEB)

    Tomberlin, G.; Mosey, G.

    2013-03-01

    Under the RE-Powering America's Land initiative, the U.S. Environmental Protection Agency (EPA) provided funding to the National Renewable Energy Laboratory (NREL) to support a feasibility study of biomass renewable energy generation at the former Farmland Industries site in Lawrence, Kansas. Feasibility assessment team members conducted a site assessment to gather information integral to this feasibility study. Information such as biomass resources, transmission availability, on-site uses for heat and power, community acceptance, and ground conditions were considered.

  14. Feasibility Study of Economics and Performance of Solar Photovoltaics at the Tower Road Site in Aurora, Colorado. A Study Prepared in Partnership with the Environmental Protection Agency for the RE-Powering America's Land Initiative: Siting Renewable Energy on Potentially Contaminated Land and Mine Sites

    Energy Technology Data Exchange (ETDEWEB)

    Van Geet, O.; Mosey, G.

    2013-03-01

    The U.S. Environmental Protection Agency (EPA), in accordance with the RE-Powering America's Land initiative, selected the Tower Road site in Aurora, Colorado, for a feasibility study of renewable energy production. The National Renewable Energy Laboratory (NREL) provided technical assistance for this project. The purpose of this report is to assess the site for a possible photovoltaic (PV) system installation and estimate the cost, performance, and site impacts of different PV options. In addition, the report recommends financing options that could assist in the implementation of a PV system at the site. This study did not assess environmental conditions at the site.

  15. Performance evaluation of LaBr3: Ce scintillator

    International Nuclear Information System (INIS)

    Xie Ming; Lin Li; Liu Shihao; Xiao Peng; Xie Qingguo

    2012-01-01

    The cerium doped lanthanum bromide crystal (LaBr 3 : Ce) is a new kind of scintillator with many advantages such as good energy resolution, high light output, short decay time, good proportionality response. These properties make the LaBr 3 : Ce attractive substantial interest to use in the radiation detection. The energy resolution were investigated with Φ25 × 25 mm LaBr 3 : Ce coupled to a Hamamatsu R8900 photomultiplier tube. Energy resolution of 3.6% (FWHM) have been achieved for 511 keV photons ( 18 F source) at room temperature. Decay time constant of 20 ns have been acquired with a Hamamatsu fast-time-response R9800 photomultiplier tube. The results approve the excellent characterizations of LaBr 3 : Ce and imply its enormous potentiality in the radiation detectors of gamma-ray spectroscopy and PET. (authors)

  16. NMR study of CeCoSi3

    International Nuclear Information System (INIS)

    Iwamoto, Y.

    1995-01-01

    Low-temperature susceptibility, NMR and NQR of the 59 Co signal in CeCoSi 3 have been measured. CeCoSi 3 showed a superconducting transition at 0.7-1.2K. From NQR measurement, the nuclear quadrupole frequency and the full width at half maximum (FWHM) of 59 Co in CeCoSi 3 were estimated to be about 1.08MHz and 0.08MHz, respectively. The 59 Co nuclear spin-lattice relaxation rate (1/T 1 ) in CeCoSi 3 was proportional to the temperature (T) as the Fermi liquid state above the superconducting transition temperature (T c ), and then rapidly decreased below T c . ((orig.))

  17. CE-MS fingerprinting of Laurencia complex algae (Rhodophyta).

    Science.gov (United States)

    Machín-Sánchez, María; Asensio-Ramos, María; Hernández-Borges, Javier; Gil-Rodríguez, María Candelaria

    2014-03-01

    The use of CE-ESI-MS has been considered as a new chemical strategy for the possible discernment of genera and species of the Laurencia complex. After the selection of the CE-MS and the extraction conditions, a total of 28 specimens of the complex, including different species of four genera (Laurencia, Laurenciella, Palisada, and Osmundea) collected from five intertidal locations on the Island of Tenerife (Canary Islands, Spain) were analyzed. CE-MS fingerprints revealed that CE-MS can be used as a useful tool for these studies in order to assess similarities and differences between them and that it constitutes an important starting point for further studies in the field. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Sr2CeO4: Electronic and structural properties

    International Nuclear Information System (INIS)

    Rocha, Leonardo A.; Schiavon, Marco A.; Nascimento, Clebio S.; Guimarães, Luciana; Góes, Márcio S.; Pires, Ana M.; Paiva-Santos, Carlos O.

    2014-01-01

    Highlights: • Sr 2 CeO 4 it was obtained from the heat treatment of Ce 3+ -doped strontium oxalate. • Rietveld analysis made it possible to obtain information about crystalline structure. • Experimental band gap value was compared with theoretical obtained by Sparkle/PM7. • The materials obtained shows intense photoluminescence and scintillator properties. - Abstract: This work presents on the preparation and photoluminescent properties of Sr 2 CeO 4 obtained from the heat treatment of Ce(III)-doped strontium oxalate (10, 25 and 33 mol%). The oxalate precursors were heat treated at 1100 °C for 12 h. The structure of this photoluminescent material was evaluated by the Rietveld method. The route used in this work to prepare the materials showed to be viable when compared to other synthesis reported in the literature. The Sr 2 CeO 4 material showed a broad and intense band emission with a maximum around 485 nm. The quantitative phase analysis showed that the Sr 2 CeO 4 photoluminescent phase is the majority one compared to the impurity phases of SrCeO 3 and SrCO 3 . From all results it was possible to verify a complete elimination of the CeO 2 phase for the sample obtained from the heat treatment of oxalate precursor containing 33 mol% of cerium(III). The material showed excellent properties for possible candidate as scintillator materials, and in the improvement of efficiency of solar cells when excited in the UV–vis region. The CIE chromaticity diagram it is also reported in this work

  19. Quadrupole moment of the superdeformed band in 131Ce

    International Nuclear Information System (INIS)

    He, Y.; Godfrey, M.J.; Jenkins, I.; Kirwan, A.J.; Nolan, P.J.

    1990-01-01

    A mean lifetime measurement has been carried out on the states in the superdeformed band found in 131 Ce using the Doppler shift attenuation method (DSAM). The measured intrinsic nuclear quadrupole moment is Q o approx= 6 eb, assuming constant deformation, which corresponds to a quadrupole deformation β 2 approx= 0.35. This is considerably smaller than the value deduced for 132 Ce. (author)

  20. Optical properties of CeO 2 thin films

    Indian Academy of Sciences (India)

    Cerium oxide (CeO2) thin films have been prepared by electron beam evaporation technique onto glass substrate at a pressure of about 6 × 10-6 Torr. The thickness of CeO2 films ranges from 140–180 nm. The optical properties of cerium oxide films are studied in the wavelength range of 200–850 nm. The film is highly ...

  1. Crystal growth and magnetic properties of equiatomic CeAl

    Science.gov (United States)

    Das, Pranab Kumar; Thamizhavel, A.

    2015-03-01

    Single crystal of CeAl has been grown by flux method using Ce-Al self-flux. Several needle like single crystals were obtained and the length of the needle corresponds to the [001] crystallographic direction. Powder x-ray diffraction revealed that CeAl crystallizes in orthorhombic CrB-type structure with space group Cmcm (no. 63). The magnetic properties have been investigated by means of magnetic susceptibility, isothermal magnetization, electrical transport, and heat capacity measurements. CeAl is found to order antiferromagnetically with a Neel temperature TN = 10 K. The magnetization data below the ordering temperature reveals two metamagentic transitions for fields less than 20 kOe. From the inverse magnetic susceptibility an effective moment of 2.66 μB/Ce has been estimated, which indicates that Ce is in its trivalent state. Electrical resistivity data clearly shows a sharp drop at 10 K due to the reduction of spin disorder scattering of conduction electrons thus confirming the magnetic ordering. The estimated residual resistivity ratio (RRR) is 33, thus indicating a good quality of the single crystal. The bulk nature of the magnetic ordering is also confirmed by heat capacity data. From the Schottky anomaly of the heat capacity we have estimated the crystal field level splitting energies of the (2J + 1) degenerate ground state as 25 K and 175 K respectively for the fist and second excited states.

  2. CE-SAM: a conversational interface for ISR mission support

    Science.gov (United States)

    Pizzocaro, Diego; Parizas, Christos; Preece, Alun; Braines, Dave; Mott, David; Bakdash, Jonathan Z.

    2013-05-01

    There is considerable interest in natural language conversational interfaces. These allow for complex user interactions with systems, such as fulfilling information requirements in dynamic environments, without requiring extensive training or a technical background (e.g. in formal query languages or schemas). To leverage the advantages of conversational interactions we propose CE-SAM (Controlled English Sensor Assignment to Missions), a system that guides users through refining and satisfying their information needs in the context of Intelligence, Surveillance, and Reconnaissance (ISR) operations. The rapidly-increasing availability of sensing assets and other information sources poses substantial challenges to effective ISR resource management. In a coalition context, the problem is even more complex, because assets may be "owned" by different partners. We show how CE-SAM allows a user to refine and relate their ISR information needs to pre-existing concepts in an ISR knowledge base, via conversational interaction implemented on a tablet device. The knowledge base is represented using Controlled English (CE) - a form of controlled natural language that is both human-readable and machine processable (i.e. can be used to implement automated reasoning). Users interact with the CE-SAM conversational interface using natural language, which the system converts to CE for feeding-back to the user for confirmation (e.g. to reduce misunderstanding). We show that this process not only allows users to access the assets that can support their mission needs, but also assists them in extending the CE knowledge base with new concepts.

  3. Cerocene Revisited: The Electronic Structure of and Interconversion Between Ce2(C8H8)3 and Ce(C8H8)2

    Energy Technology Data Exchange (ETDEWEB)

    Walter, Marc D.; Booth, Corwin H.; Lukens, Wayne W.; Andersen, Richard A.

    2009-02-02

    New synthetic procedures for the preparation of Ce(cot)2, cerocene, from [Li(thf)4][Ce(cot)2], and Ce2(cot)3 in high yield and purity are reported. Heating solid Ce(cot)2 yields Ce2(cot)3 and COT while heating Ce2(cot)3 with an excess of COT in C6D6 to 65oC over four months yields Ce(cot)2. The solid state magnetic susceptibility of these three organocerium compounds shows that Ce(cot)2 behaves as a TIP (temperature independent paramagnet) over the temperature range of 5-300 K, while that of Ce2(cot)3 shows that the spin carriers are antiferromagnetically coupled below 10 K; above 10 K, the individual spins are uncorrelated, and [Ce(cot)2]- behaves as an isolated f1 paramagnet. The EPR at 1.5K for Ce2(cot)3 and [Ce(cot)2]- have ground state of MJ= +- 1/2. The LIII edge XANES of Ce(cot)2 (Booth, C.H.; Walter, M.D.; Daniel, M.; Lukens, W.W., Andersen, R.A., Phys. Rev. Lett. 2005, 95, 267202) and 2Ce2(cot)3 over 30-500 K are reported; the Ce(cot)2 XANES spectra show Ce(III) and Ce(IV) signatures up to a temperature of approximately 500 K, whereupon the Ce(IV) signature disappears, consistent with the thermal behavior observed in the melting experiment. The EXAFS of Ce(cot)2 and Ce2(cot)3 are reported at 30 K; the agreement between the molecular parameters for Ce(cot)2 derived from EXAFS and single crystal X-ray diffraction data are excellent. In the case of Ce2(cot)3 no X-ray diffraction data are known to exist, but the EXAFS are consistent with a"triple-decker" sandwich structure. A molecular rationalization is presented for the electronic structure of cerocene having a multiconfiguration ground state that is an admixture of the two configurations Ce(III, 4f1)(cot1.5-)2 and Ce(IV, 4f0)(cot2-)2; the multiconfigurational ground state has profound effects on the magnetic properties and on the nature of the chemical bond in cerocene and, perhaps, other molecules.

  4. Comparison between the Oxygen Reduction Reaction Activity of Pd5Ce and Pt5Ce

    DEFF Research Database (Denmark)

    Tripkovic, Vladimir; Zheng, Jian; Rizzi, Gian Andrea

    2015-01-01

    A set of electrochemical and X-ray spectroscopy measurements have been used conjointly with density functional theory (DFT) simulations to study the activity and stability of Pd5Ce for the oxygen reduction reaction. A polycrystalline Pd5Ce rod has been selected as a model catalyst to test if resu......-Pd5Ce is more facile, requires less atom rearrangement, than transformation from Pt5Ce to Pt3Ce, which might explain the kinetic stability of Pt5Ce at low temperatures....

  5. The CE3R Network: current status and future perspectives

    Science.gov (United States)

    Lenhardt, Wolfgang; Pesaresi, Damiano; Živčić, Mladen; Costa, Giovanni; Kuk, Kresimir; Bondár, István; Duni, Llambro; Spacek, Petr

    2016-04-01

    In order to improve the monitoring of seismic activities in the border regions and to enhance the collaboration between countries and seismological institutions in Central Europe, the Environment Agency of the Slovenian Republic (ARSO), the Italian National Institute for Oceanography and Experimental Geophysics (OGS), the University of Trieste (UniTS) and the Austrian Central Institute for Meteorology and Geodynamics (ZAMG) established in 2001 the "South Eastern Alps Transfrontier Seismological Network". In May 2014 ARSO, OGS, UniTS and ZAMG agreed to formalize the transfrontier network, to name it "Central and East European Earthquake Research Network", (CE3RN or CE3R Network) in order to locate it geographically since cross-border networks can be established in other areas of the world and to expand their cooperation, including institutions in other countries. The University of Zagreb (UniZG) joined CE3RN in October 2014. The Kövesligethy Radó Seismological Observatory (KRSZO) of the Hungarian Academy of Sciences joined CE3RN in October 2015. The Institute of Geosciences, Energy, Water and Environment (IGEWE) of the Polytechnic University of Tirana joined CE3RN in November 2015. The Institute of Physics of the Earth (IPE) of the Masaryk University in Brno joined CE3RN in November 2015. CE3RN Parties intend to formalize and possibly extend their ongoing cooperation in the field of seismological data acquisition, exchange and use for seismological and earthquake engineering and civil protection purposes. The purpose of this cooperation is to retain and expand the existing cross-border network, specify the rules of conduct in the network management, improvements, extensions and enlargements, enhance seismological research in the region, and support civil protection activities. Since the formal establishment of CE3RN, several common projects have been completed, like the SeismoSAT project for the seismic data center connection over satellite funded by the Interreg

  6. The role of calcification for staging cystic echinococcosis (CE)

    Energy Technology Data Exchange (ETDEWEB)

    Hosch, Waldemar; Kauffmann, Guenter W. [University Hospital Heidelberg, Department of Radiology, Heidelberg (Germany); Stojkovic, Marija; Junghanss, Thomas [University Hospital of Heidelberg, Section of Clinical Tropical Medicine, Heidelberg (Germany); Jaenisch, Thomas [University Hospital of Heidelberg, Section of Clinical Tropical Medicine, Heidelberg (Germany); University Hospital of Heidelberg, Section of Biostatistics and Epidemiology, Heidelberg (Germany)

    2007-10-15

    The prevalence of calcified cysts and the significance of calcification as a sign of cyst inactivity in cystic echinococcosis (CE) was evaluated. Seventy-eight patients (36 females, 42 males, mean age 40.8 {+-} 16.9 years) with CE, having a total of 137 abdominal cysts (116 hepatic, three splenic, one renal and 17 peritoneal cysts), were diagnosed and followed-up by ultrasound during and after albendazole treatment or as part of the watch-and-wait approach recording changes in the cyst wall and content. In 48 patients with 94 cysts, computed tomography (CT) imaging was additionally available and was correlated with ultrasound findings. Cyst wall calcification was classified into (1) ''sprinkled'', (2) ''eggshell-like'', and (3) ''circular''. Calcification of the cyst wall and/or cyst content was detected in 67 echinococcal cysts (48.9% of all cysts) in 39 patients (15 females, 24 males, mean age 40.8 {+-} 14.8 years). Of the total of 67 calcified cysts, only 23 were compatible with WHO type CE5, 18 with WHO type CE4. Judged by cyst content, the remaining 26 were of WHO type CE1, CE2 and CE3 (n = 1, n = 8, and n = 17, respectively). During a mean period of 34.3 months ({+-}21.3 months) the majority of cysts (n = 32) did not exhibit any change in cyst content and wall properties. Fourteen cysts showed signs of progressive involution, five cysts (all of WHO type CE3) of renewed activity defined by recurring fluid collection. In 16 cysts, no follow-up was available due to surgery or drop out. Calcification of the cyst is not restricted to the inactive WHO cyst types CE4 and CE5, but occurs in all stages and in up to 50% of cysts. The completeness and, most importantly, the stability of consolidation of cyst content over time predicts cyst inactivity more reliably. (orig.)

  7. Crystal growth and scintillation properties of multi-component oxide single crystals: Ce:GGAG and Ce:La-GPS

    Energy Technology Data Exchange (ETDEWEB)

    Yoshikawa, A., E-mail: yoshikawa@imr.tohoku.ac.jp [Institute for Materials Research (IMR), Tohoku University, Sendai 980-8577 (Japan); New Industry Creation Hatchery Center (NICHe), Tohoku University, Sendai 980-8579 (Japan); C& A Corporation, 6-6-40 Aramaki Aza Aoba, Aoba-ku, Sendai 980-8579 (Japan); Kamada, K. [New Industry Creation Hatchery Center (NICHe), Tohoku University, Sendai 980-8579 (Japan); C& A Corporation, 6-6-40 Aramaki Aza Aoba, Aoba-ku, Sendai 980-8579 (Japan); Kurosawa, S. [Institute for Materials Research (IMR), Tohoku University, Sendai 980-8577 (Japan); New Industry Creation Hatchery Center (NICHe), Tohoku University, Sendai 980-8579 (Japan); Shoji, Y. [Institute for Materials Research (IMR), Tohoku University, Sendai 980-8577 (Japan); C& A Corporation, 6-6-40 Aramaki Aza Aoba, Aoba-ku, Sendai 980-8579 (Japan); Yokota, Y. [New Industry Creation Hatchery Center (NICHe), Tohoku University, Sendai 980-8579 (Japan); Chani, V.I. [Institute for Materials Research (IMR), Tohoku University, Sendai 980-8577 (Japan); Nikl, M. [Institute of Physics, AS CR, Cukrovarnická 10, 162 53 Prague (Czech Republic)

    2016-01-15

    Crystal growth by micro-pulling-down, Czochralski, and floating zone methods and scintillation properties of Ce:Gd{sub 3}(Ga,Al){sub 5}O{sub 12} (Ce:GGAG) multi-component oxide garnets, and Ce:Gd{sub 2}Si{sub 2}O{sub 7} (Ce:GPS) or Ce:(La,Gd){sub 2}Si{sub 2}O{sub 7} (Ce:La-GPS) pyro-silicates are reviewed. GGAG crystals demonstrated practically linear dependences of some of the parameters including lattice constant, emission wavelength, and band gap on Ga content. However, emission intensity, light yield and energy resolution showed maxima for intermediate compositions. GGAG crystals had the highest light yield of 56,000 photon/MeV for Ga content of 2.7 atoms per garnet formula unit. Similarly the light yield and energy resolution of La-GPS showed the highest values of 40,000 photon/MeV and 4.4%@662 keV, respectively, for La-GPS containing 10% of La. Moreover, La-GPS demonstrated stable scintillation performance up to 200 °C.

  8. Ce decay curves in Ce, Tb co-doped LaF3 and the energy transfer mechanism

    International Nuclear Information System (INIS)

    Kroon, R.E.; Swart, H.C.; Ntwaeaborwa, O.M.; Seed Ahmed, H.A.A.

    2014-01-01

    Energy transfer phenomena can play an important role in the development of luminescent materials, and hosts co-doped with Ce 3+ and Tb 3+ ions continue to be actively studied. Several recent reports on Ce, Tb co-doped phosphors suggest different mechanisms for the energy transfer from Ce 3+ to Tb 3+ ions and further study is required to reach consensus on the mechanism or to understand why different mechanisms dominate in different hosts. A more direct method of analysis is proposed to distinguish between the different types of multipole energy transfer mechanisms. When applied to Ce, Tb co-doped LaF 3 , the experimental data shows a poor match to any of these models but is consistent with energy transfer through the exchange mechanism. The decay curves of Ce emission in Ce, Tb co-doped LaF 3 were also studied to obtain further insight on the energy transfer mechanism. Although the decrease in lifetime with increasing Tb concentration shows that energy transfer occurs through a non-radiative mechanism, the form of the decay curves does not correspond to what is expected for energy transfer via multipole interactions.

  9. Optical and scintillation properties of Ce-doped LuLiF{sub 4} with different Ce concentrations

    Energy Technology Data Exchange (ETDEWEB)

    Yanagida, Takayuki, E-mail: yanagida@lsse.kyutech.ac.jp [Kyushu Institute of Technology, 2-4 Hibikino, Wakamatsu-ku, Kitakyushu, Fukuoka 808-0196 (Japan); Fujimoto, Yutaka [Kyushu Institute of Technology, 2-4 Hibikino, Wakamatsu-ku, Kitakyushu, Fukuoka 808-0196 (Japan); Fukuda, Kentaro [Tokuyama Corporation, Shibuya 3-chome, Shibuya-ku, Tokyo 150-8383 Japan (Japan); Chani, Valery [Tohoku Univ., 2-1-1 Katahira, Sendai 980-8577 (Japan)

    2013-11-21

    The crystals of 0.1, 0.5, and 1 mol% Ce-doped LuLiF{sub 4} (Ce:LLF) grown by the micro-pulling down (μ-PD) method were examined for their optical and scintillation properties. Ce:LLF crystals had ∼80% transparency at wavelengths longer than 300 nm. In photoluminescence spectra, they demonstrated intense emission peaks at 310 and 330 nm with the quantum yield of 60–90%. Ce{sup 3+} 5d–4f emission peaks were also detected at similar wavelengths of 310 and 330 nm in the radioluminescence spectra obtained under X-ray excitation. According to pulse height spectra recorded under γ-ray irradiation, the absolute light yield of Ce 0.1, 0.5, and 1% were 3600±400, 3000±300, and 1700±200 ph/MeV, respectively. Decay time kinetics was also inspected using a pulse X-ray equipped streak camera system. The decay time components of Ce:LLF were ∼70 ns and ∼1 μs for all the samples.

  10. Optical and scintillation properties of Ce-doped LuLiF4 with different Ce concentrations

    International Nuclear Information System (INIS)

    Yanagida, Takayuki; Fujimoto, Yutaka; Fukuda, Kentaro; Chani, Valery

    2013-01-01

    The crystals of 0.1, 0.5, and 1 mol% Ce-doped LuLiF 4 (Ce:LLF) grown by the micro-pulling down (μ-PD) method were examined for their optical and scintillation properties. Ce:LLF crystals had ∼80% transparency at wavelengths longer than 300 nm. In photoluminescence spectra, they demonstrated intense emission peaks at 310 and 330 nm with the quantum yield of 60–90%. Ce 3+ 5d–4f emission peaks were also detected at similar wavelengths of 310 and 330 nm in the radioluminescence spectra obtained under X-ray excitation. According to pulse height spectra recorded under γ-ray irradiation, the absolute light yield of Ce 0.1, 0.5, and 1% were 3600±400, 3000±300, and 1700±200 ph/MeV, respectively. Decay time kinetics was also inspected using a pulse X-ray equipped streak camera system. The decay time components of Ce:LLF were ∼70 ns and ∼1 μs for all the samples

  11. Influence of Ce-H bonding on the physical properties of the hydrides CeCoSiH1.0 and CeCoGeH1.0

    International Nuclear Information System (INIS)

    Chevalier, B; Matar, S F; Menetrier, M; Marcos, J Sanchez; Fernandez, J Rodriguez

    2006-01-01

    The hydrides CeCoSiH 1.0 and CeCoGeH 1.0 which crystallize like the parent antiferromagnetic compounds CeCoSi and CeCoGe in the tetragonal CeFeSi-type structure, have been investigated by specific heat and thermoelectric power measurements and 1 H nuclear magnetic resonance (NMR). CeCoSiH 1.0 is an intermediate valence compound whereas CeCoGeH 1.0 can be considered as a nearly trivalent cerium compound. This behaviour is corroborated by the occurrence of a slight broadening of the 1 H NMR signal in the sequence CeCoSiH 1.0 → CeCoGeH 1.0 . The band structure calculations performed on these hydrides reveal the existence of strong bonding Ce-H interaction, found to be larger in CeCoSiH 1.0 than in CeCoGeH 1.0

  12. Effect of yttrium on electron–phonon coupling strength of 5d state of Ce3+ ion in LYSO:Ce crystals

    International Nuclear Information System (INIS)

    Ding, Dongzhou; Liu, Bo; Wu, Yuntao; Yang, Jianhua; Ren, Guohao; Chen, Junfeng

    2014-01-01

    This paper aims at an improved understanding of luminescence properties of (Lu 1−x Y x ) 2 SiO 5 :Ce (x=0 at%, 26 at%, 45 at%, 66 at% and 100 at%). Photoluminescence emission and excitation spectra as well as Raman spectra of (Lu 1−x Y x ) 2 SiO 5 :Ce were investigated as a function of yttrium (shortened as Y) content in it. Obtained Huang–Rhys factor S indicates that the coupling between Ce1 (7-oxygen-coordinated), Ce2 (6-oxygen-coordinated) and LYSO lattice is intermediate and strong, respectively. Besides, it was found that: with the increase of Y content, crystal field strength around Ce1 and Ce2 decreases, Stokes shift of Ce1 and Ce2 presents an increase trend, and S of Ce2 tends to decrease. These phenomena were explained by geometrical influence of Y 3+ /Lu 3+ on the crystal field splitting of the 5d levels of Ce 3+ and coupling strength. With the increase of Y content, the evolution of S and coupling energy ħω of Ce1 present a slight increase and decrease trend respectively, while S and coupling energy ħω of Ce2 present an obvious decrease and increase trend, respectively. - Highlights: • Crystal field strength around Ce1 decreases with increase of Y content in LYSO:Ce. • A diagram of Huang–Rhys factor S against Y content in LYSO:Ce was constructed. • A diagram of coupling energy ħω against Y content in LYSO:Ce was constructed. • A diagram of Stokes shift against Y content in LYSO:Ce was constructed

  13. Ce-doped nanoparticles of TiO2: Rutile-to-brookite phase transition and evolution of Ce local-structure studied with XRD and XANES

    International Nuclear Information System (INIS)

    Kityakarn, Sutasinee; Worayingyong, Attera; Suramitr, Anwaraporn; Smith, M.F.

    2013-01-01

    The crystal and electronic structural changes undergone by TiO 2 nanoparticles when Ce is introduced were studied using X-ray diffraction (XRD) and X-ray absorption near-edge spectroscopy (XANES). A small amount of Ce (less than 1% molar concentration) resulted in i/a significant reduction of the average size of the TiO 2 nanoparticles and ii/a phase transition in which brookite replaced rutile as the minority phase component (anatase was the majority phase component at all Ce concentrations studied up to 10% molar concentration). The Ce L3 edge XANES revealed changes in the local environment of Ce impurities. As Ce concentration was increased the fraction of Ce that have formal valence of +3 decreased and, for the remaining Ce with valence +4, the 4f orbitals became less-strongly hybridized with the p-orbitals of oxygen neighbors. The results have implications for photocatalytic and gas sensing properties of Ce-doped TiO 2 . - Highlights: ► Ce-doping: TiO 2 nanoparticles shrink and minority phase changes rutile-> brookite. ► XANES reveals phase change for arbitrarily small particles (while XRD fails). ► As Ce added: fraction of Ce +3 dopants falls, hybridization of Ce +4 with O weakens

  14. Investigating the capability of ToF-SIMS to determine the oxidation state of Ce

    Science.gov (United States)

    Seed Ahmed, H. A. A.; Swart, H. C.; Kroon, R. E.

    2018-04-01

    The capability of time of flight secondary ion mass spectrometry (ToF-SIMS) to determine the oxidation state of Ce ions doped in a phosphor was investigated. Two samples of SiO2:Ce (4 mol%) with known Ce3+/Ce4+ relative concentrations were subjected to ToF-SIMS measurements. The spectra were very similar and no significant differences in the relative peak intensities were observed that would readily allow one to distinguish Ce3+ from Ce4+. Although ToF-SIMS was therefore not useful to distinguish the charge state of Ce ions doped in this phosphor material, the idea in principle was also tested on two other samples, namely CeF3 and CeF4 These contain Ce as part of the host (i.e. much higher concentration) and are fluorides, which is significant because ToF-SIMS has previously been reported to be able to distinguish Eu2+ from Eu3+ in Eu doped Sr5(PO4)3F phosphor. The spectrum of CeF4 contained a small peak related to Ce4+ which was not observed in the CeF3 spectrum, yet the peak related to the Ce3+ ions was found to be much more intense in the spectrum of CeF4 than CeF3, showing that the ToF-SIMS signals cannot be directly interpreted as retaining the charge state of the ions in the original material. Nevertheless, the significant differences in the Ce-related peaks in the ToF-SIMS spectra from CeF3 and CeF4 show that the charge state of Ce may be distinguished. This study shows that while in principle ToF-SIMS may be used to distinguish the charge state of Ce ions, this depends on the sample and it would not be easy to interpret the spectra without a standard or reference.

  15. Loparite-(Ce) from the Khibiny Alkaline Pluton, Kola Peninsula, Russia

    Science.gov (United States)

    Konopleva, N. G.; Ivanyuk, G. Yu.; Pakhomovsky, Ya. A.; Yakovenchuk, V. N.; Mikhailova, Yu. A.

    2017-12-01

    Data on the occurrence, morphology, anatomy, composition, and formation conditions of loparite-(Ce) in the Khibiny alkaline pluton are given. Loparite-(Ce), (Na,Ce,Sr)(Ce,Th)(Ti,Nb)2O6, resulted from metasomatic alteration and assimilation of metamorphic host rocks at the contact with foyaite as well as foyaite on the contact with foidolite. This alteration was the highest in pegmatite, and albitite developed there. A decrease in temperature resulted in enrichment of the perovskite and tausonite endmembers in loparite-(Ce) owing to a decrease in the loparite and lueshite endmembers. La and Ce sharply predominate among rare earth elements in the composition of loparite-(Ce).

  16. The crystal structure of galgenbergite-(Ce), CaCe2(CO3)4•H2O

    Science.gov (United States)

    Walter, Franz; Bojar, Hans-Peter; Hollerer, Christine E.; Mereiter, Kurt

    2013-04-01

    Galgenbergite-(Ce) from the type locality, the railroad tunnel Galgenberg between Leoben and St. Michael, Styria, Austria, was investigated. There it occurs in small fissures of an albite-chlorite schist as very thin tabular crystals building rosette-shaped aggregates associated with siderite, ancylite-(Ce), pyrite and calcite. Electron microprobe analyses gave CaO 9.49, Ce2O3 28.95, La2O3 11.70, Nd2O3 11.86, Pr2O3 3.48, CO2 30.00, H2O 3.07, total 98.55 wt.%. CO2 and H2O calculated by stoichiometry. The empirical formula (based on Ca + REE ∑3.0) is C{{a}_{1.00 }}{{( {C{{e}_{1.04 }}L{{a}_{0.42 }}N{{d}_{0.42 }}P{{r}_{0.12 }}} )}_{2.00 }}{{( {C{{O}_3}} )}_4}\\cdot {{H}_2}O , and the simplified formula is CaC{{e}_2}{{( {C{{O}_3}} )}_4}\\cdot {{H}_2}O . According to X-ray single crystal diffraction galgenbergite-(Ce) is triclinic, space group Poverline{1},a=6.3916(5) , b = 6.4005(4), c = 12.3898(9) Å, α = 100.884(4), β = 96.525(4), γ = 100.492(4)°, V = 483.64(6) Å3, Z = 2. The eight strongest lines in the powder X-ray diffraction pattern are [ d calc in Å/( I)/ hkl]: 5.052/(100)/011; 3.011/(70)/0-22; 3.006/(66)/004; 5.899/(59)/-101; 3.900/(51)/1-12; 3.125/(46)/-201; 2.526/(42)/022; 4.694/(38)/-102. The infrared absorption spectrum reveals H2O (OH-stretching mode at 3,489 cm-1, HOH bending mode at 1,607 cm-1) and indicates the presence of distinctly non-equivalent CO3-groups by double and quadruple peaks of their ν1, ν2, ν3 and ν4 modes. The crystal structure of galgenbergite-(Ce) was refined with X-ray single crystal data to R1 = 0.019 for 2,448 unique reflections ( I > 2 σ( I)) and 193 parameters. The three cation sites of the structure Ca(1), Ce(2) and Ce(3) have a modest mixed site occupation by Ca and small amount of REE (Ce, La, Pr, Nd) and vice versa. The structure is based on double layers parallel to (001), which are composed of Ca(1)Ce(2)(CO3)2 single layers with an ordered chessboard like arrangement of Ca and Ce, and with a roof tile

  17. SELF-ASSEMBLY CE OXIDE/ORGANOPOLYSILOXANE COMPOSITE COATINGS.

    Energy Technology Data Exchange (ETDEWEB)

    SUGAMA,T.; SABATINI,R.; GAWLIK,K.

    2005-01-01

    A self-assembly composite synthesis technology was used to put together a Ce(OH){sub 3}-dispersed poly-acetamide-acetoxyl methyl-propylsiloxane (PAAMPA) organometallic polymer. Three spontaneous reactions were involved; condensation, amidation, and acetoxylation, between the Ce acetate and aminopropylsilane triol (APST) at 150 C. An increase in temperature to 200 C led to the in-situ phase transformation of Ce(OH){sub 3} into Ce{sub 2}O{sub 3} in the PAAMPA matrix. A further increase to 250 C caused oxidative degradation of the PAAMPA, thereby generating copious fissures in the composite. We assessed the potential of Ce(OH){sub 3}/ and Ce{sub 2}O{sub 3}/ PAAMPA composite materials as corrosion-preventing coatings for carbon steel and aluminum. The Ce{sub 2}O{sub 3} composite coating displayed better performance in protecting both metals against NaCl-caused corrosion than did the Ce(OH){sub 3} composite. Using this coating formed at 200 C, we demonstrated that the following four factors played an essential role in further mitigating the corrosion of the metals: First was a minimum susceptibility of coating's surface to moisture; second was an enhanced densification of the coating layer; third was the retardation of the cathodic oxygen reduction reaction at the metal's corrosion sites due to the deposition of Ce{sub 2}O{sub 3} as a passive film over the metal's surface; and, fourth was its good adherence to metals. The last two factors contributed to minimizing the cathodic delamination of coating film from the metal's surface. We also noted that the affinity of the composite with the surface of aluminum was much stronger than that with steel. Correspondingly, the rate of corrosion of aluminum was reduced as much as two orders of magnitude by a nanoscale thick coating. In contrast, its ability to reduce the corrosion rate of steel was lower than one order of magnitude.

  18. Levels in 146Ce and the N = 88 isotones

    International Nuclear Information System (INIS)

    Gowdy, G.M.; Chrien, R.E.; Chu, Y.Y.

    1981-01-01

    An investigation of the level structure of 146 Ce following the beta decay of the low-spin isomer of 146 La has been carried out at the ISOL facility TRISTAN at Brookhaven National Laboratory. The half-life for the low spin isomer was found to be 6.0 +- 0.4s. A partial level scheme for 146 Ce below 2 MeV is given. The level energies and some B(E2) values extracted from our data have been compared with IBA-2 calculations done entirely with extrapolated parameters from neighboring Z nuclei in order to check the predictive power of the model. Systematics of the Z = 58 isotopes and N = 88 isotones indicate that although 146 Ce is more deformed than its isotones with Z greater than or equal to 60, the transition to the well-deformed region can probably more correctly be thought to occur after 146 Ce, between N = 88 and N = 90, as it does for Z greater than or equal to 60. The abrupt onset of deformation present in the higher Z isotopes is not seen in the Ce isotopes where the trend is found to be rather smooth throughout

  19. An Update on NiCE Support for BISON

    Energy Technology Data Exchange (ETDEWEB)

    McCaskey, Alex [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Billings, Jay Jay [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Deyton, Jordan H. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Wojtowicz, Anna [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2015-09-01

    The Nuclear Energy Advanced Modeling and Simulation program (NEAMS) from the Department of Energy s Office of Nuclear Energy has funded the development of a modeling and simulation workflow environment to support the various codes in its nuclear energy scientific computing toolkit. This NEAMS Integrated Computational Environment (NiCE) provides extensible tools and services that enable efficient code execution, input generation, pre-processing visualizations, and post-simulation data analysis and visualization for a large portion of the NEAMS Toolkit. A strong focus for the NiCE development team throughout FY 2015 has been support for the Multiphysics Object Oriented Simulation Environment (MOOSE) and the NEAMS nuclear fuel performance modeling application built on that environment, BISON. There is a strong desire in the program to enable and facilitate the use of BISON throughout nuclear energy research and industry. A primary result of this desire is the need for strong support for BISON in NiCE. This report will detail improvements to NiCE support for BISON. We will present a new and improved interface for interacting with BISON simulations in a variety of ways: (1) improved input model generation, (2) embedded mesh and solution data visualizations, and (3) local and remote BISON simulation launch. We will also show how NiCE has been extended to provide support for BISON code development.

  20. Using Ce to modify inclusion in spring steel

    Directory of Open Access Journals (Sweden)

    Wang Q.

    2017-01-01

    Full Text Available The effect of rare earth metals addition on the Al2O3 inclusions in spring steel used in fastener of high speed railway was investigated by metallographic examination, SEM-EDS and composition analysis. To deform those harmful inclusions to improve material performance,the evolution process of Al2O3 inclusions was investigated through the surface and line scanning. Ce metal modifying Al2O3 is a stepwise reduction process based on a formation of ring shape Ce-riched band around the Al2O3 inclusions during reaction process. Through experiment and thermodynamic calculation, an evolvement rule about Al2O3 inclusions change after Ce addition is obtained, i.e. Al2O3→Ce2O3-Al2O3→Ce2O2S. Changing the inclusions from Al2O3 to rare earth inclusions could improve the resistance to pitting corrosion based on potentiodynamic anodic polarization test.

  1. Mechanochemical synthesis of ultrafine Ce2S3 powder

    International Nuclear Information System (INIS)

    Tsuzuki, T.; McCormick, P.G.

    1998-01-01

    Full text: Rare earth sulphides have been receiving an increasing attraction for various applications including infrared window materials and magneto-optical devices. In particular, Ce 2 S 3 has been under intensive study for use as a red pigment to replace toxic cadmium sulfoselenide. The conventional method for synthesising Ce 2 S 3 is the sulphidization of the element or sesquioxide with hydrogen sulphide gas. However, the method usually requires a high-temperature process (>1000 deg C), and hence coarse particles larger than the optimal size of ∼ 2 S 3 powder by mechanochemical processing using X-ray diffraction spectroscopy, BET surface area analysis and transmission electron microscopy. Mechanical milling of the mixture of a cerium salt and an alkali/alkali-earth sulphide powders led to a solid state displacement reaction in a steady-state manner, forming Ce 2 S 3 nanoparticles in a salt by-product matrix. After a simple washing process to remove the salt by-product, ultrafine Ce 2 S 3 particles with sizes of 20 - 200 nm having an orthorhombic structure were obtained. Using a diluent and mechanically alloyed CaS nanoparticles in the starting powder, particles of only a cubic γ-Ce 2 S 3 phase with sizes of 10 - 80 nm were formed

  2. Proximity effect of Pb on CeCu6 and La0.05Ce0.95Cu6

    International Nuclear Information System (INIS)

    Chen, T.P.; Tipparachi, U.; Yang, H.D.; Wang, J.T.; Chen, B.; Chen, J.C.J.

    1999-01-01

    Heavy fermion materials have attracted a great deal of attention since 1979. These materials which contain a rare earth (U, or Ce, etc.) element exhibit unusual behavior at low temperature. The effective mass m* of the Landau quasiparticles is found to be orders of magnitude higher than that of a bare electron. Some of the Heavy Fermion materials become superconductors at low temperature. The pairing of electrons in these superconductors may not be of s symmetry like those in BCS type superconductors. The mismatch in electronic mass and the difference in pairing state between the light conventional superconducting electrons and the heavy fermion electrons have brought the coupling between light electrons (BCS type) and the heavy fermion electrons into question. Proximity effect of Pb on CeCu 6 , Pb on La 0.05 Ce 0.95 Cu 6 , and Pb on Cu was used to investigate the coupling between the conventional superconducting electrons of Pb and the heavy electrons in CeCu 6 or La 0.05 Ce 0.95 Cu 6 . In this experiment proximity effect was found between Pb and CeCu 6 , as well as between Pb and La 0.05 Ce 0.95 Cu 6 . However, the proximity effect is small when compared with that between Pb and Cu. This indicates a much shorter extrapolation length in the heavy fermion materials than in Cu. Such a phenomenon can be explained by the mismatch in effective mass between the superconducting Pb electrons and the heavy fermion electrons

  3. Neutron scattering study of Ce3Au3Sb4

    International Nuclear Information System (INIS)

    Kasaya, Mitsuo; Katoh, Kenichi; Kohgi, Masahumi; Osakabe, Toyotaka

    1993-01-01

    Rare-earth compounds with an Y 3 Au 3 Sb 4 -type crystal structure are semiconductors or semi-metals. Among them, Ce 3 Au 3 Sb 4 is a semiconductor with an activation energy of about 640 K and shows no magnetic order down to 1.5 K. The magnetic part of the specific heat for Ce 3 Au 3 Sb 4 obtained by subtracting the value for La 3 Au 3 Sb 4 from the total specific heat of Ce 3 Au 3 Sb 4 shows a broad peak at around 10 K, the origin of which is well explained by the crystalline-field splitting determined by neutron scattering. (author)

  4. Electron traps and scintillation mechanism in YAlO3:Ce and LuAlO3:Ce scintillators

    International Nuclear Information System (INIS)

    Wojtowicz, A.J.; Glodo, J.; Drozdowski, W.; Przegietka, K.R.

    1998-01-01

    In this paper we present the results of thermoluminescence, isothermal decay and scintillation light yield measurements on two isostructural scintillator materials, YAlO 3 :Ce and LuAlO 3 :Ce. In addition to the variety of deep traps identified by thermoluminescence and isothermal decays, scintillation light yield experiments demonstrate the presence in both materials of a number of relatively shallow traps. While the deep traps may reduce the scintillation light yield, they do not influence the kinetics of the process. The shallow traps, on the other hand, by interfering with the process of radiative recombination of charge carriers via Ce 3+ ions, can strongly affect not only the yield of the scintillation process but its kinetics as well. The presence of shallow traps provides a consistent explanation for a number of poorly understood relationships between the two scintillator materials, including a higher room temperature scintillation light yield and longer scintillation decay time in YAlO 3 :Ce, and a longer scintillation rise time in LuAlO 3 :Ce. Theoretical analysis indicates that elimination of these traps would make the two materials nearly identical in scintillator performance. Although the specific identity of all traps remains elusive, the performance of both scintillator materials is now, in practical terms, fully understood. (Copyright (c) 1998 Elsevier Science B.V., Amsterdam. All rights reserved.)

  5. Mechanical properties of non-centrosymmetric CePt3Si and CePt3B

    Science.gov (United States)

    Rogl, G.; Legut, D.; Sýkora, R.; Müller, P.; Müller, H.; Bauer, E.; Puchegger, S.; Zehetbauer, M.; Rogl, P.

    2017-05-01

    Elastic moduli, hardness (both at room temperature) and thermal expansion (4.2-670 K) have been experimentally determined for polycrystalline CePt3Si and its prototype compound CePt3B as well as for single-crystalline CePt3Si. Resonant ultrasound spectroscopy was used to determine elastic properties (Young’s modulus E and Poisson’s ratio ν) via the eigenfrequencies of the sample and the knowledge of sample mass and dimensions. Bulk and shear moduli were calculated from E and ν, and the respective Debye temperatures were derived. In addition, ab initio DFT calculations were carried out for both compounds. A comparison of parameters evaluated from DFT with those of experiments revealed, in general, satisfactory agreement. Positive and negative thermal expansion values obtained from CePt3Si single crystal data are fairly well explained in terms of the crystalline electric field model, using CEF parameters derived recently from inelastic neutron scattering. DFT calculations, in addition, demonstrate that the atomic vibrations keep almost unaffected by the antisymmetric spin-orbit coupling present in systems with crystal structures having no inversion symmetry. This is opposite to electronic properties, where the antisymmetric spin-orbit interaction has shown to distinctly influence features like the superconducting condensate of CePt3Si.

  6. Homoleptic Ce(III) and Ce(IV) Nitroxide Complexes: Significant Stabilization of the 4+ Oxidation State

    Energy Technology Data Exchange (ETDEWEB)

    Bogart, Justin A.; Lewis, Andrew J.; Medling, Scott A.; Piro, Nicholas A.; Carroll, Patrick J.; Booth, Corwin H.; Schelter, Eric J.

    2014-06-25

    Electrochemical experiments performed on the complex Ce-IV[2-((BuNO)-Bu-t)py](4), where [2-((BuNO)-Bu-t)py](-) = N-tert-butyl-N-2-pyridylnitroxide, indicate a 2.51 V stabilization of the 4+ oxidation state of Ce compared to [(Bu4N)-Bu-n](2)[Ce(NO3)(6)] in acetonitrile and a 2.95 V stabilization compared to the standard potential for the ion under aqueous conditions. Density functional theory calculations suggest that this preference for the higher oxidation state is a result of the tetrakis(nitroxide) ligand framework at the Ce cation, which allows for effective electron donation into, and partial covalent overlap with, vacant 4f orbitals with delta symmetry. The results speak to the behavior of CeO2 and related solid solutions in oxygen uptake and transport applications, in particular an inherent local character of bonding that stabilizes the 4+ oxidation state. The results indicate a cerium(IV) complex that has been stabilized to an unprecedented degree through tuning of its ligand-field environment.

  7. Surface and bulk 4f-photoemission spectra of CeIn3 and CeSn3

    International Nuclear Information System (INIS)

    Kim, H.; Tjernberg, O.; Chiaia, G.; Kumigashira, H.; Takahashi, T.; Duo, L.; Sakai, O.; Kasaya, M.; Lindau, I.

    1997-01-01

    Resonant photoemission spectroscopy was performed on CeIn 3 and CeSn 3 at the 4d-4f and 3d-4f core thresholds. Using the different surface sensitivity between the two photon energies, surface and bulk 4f-photoemission spectra were derived for both compounds. With the noncrossing approximation of the Anderson impurity model, the 4d-4f resonant spectra together with the surface and bulk spectra were self-consistently analyzed to obtain the microscopic parameters such as the 4f-electron energy and the hybridization strength with conduction electrons. The result shows a substantial difference in these parameters between the surface and the bulk, indicating that it is important to take into account the surface effect in analyzing photoemission spectra of Ce compounds. It is also found that the 4f surface core-level shift is different between CeIn 3 and CeSn 3 . copyright 1997 The American Physical Society

  8. Pd/CeO2/SiC Chemical Sensors

    Science.gov (United States)

    Lu, Weijie; Collins, W. Eugene

    2005-01-01

    The incorporation of nanostructured interfacial layers of CeO2 has been proposed to enhance the performances of Pd/SiC Schottky diodes used to sense hydrogen and hydrocarbons at high temperatures. If successful, this development could prove beneficial in numerous applications in which there are requirements to sense hydrogen and hydrocarbons at high temperatures: examples include monitoring of exhaust gases from engines and detecting fires. Sensitivity and thermal stability are major considerations affecting the development of high-temperature chemical sensors. In the case of a metal/SiC Schottky diode for a number of metals, the SiC becomes more chemically active in the presence of the thin metal film on the SiC surface at high temperature. This increase in chemical reactivity causes changes in chemical composition and structure of the metal/SiC interface. The practical effect of the changes is to alter the electronic and other properties of the device in such a manner as to degrade its performance as a chemical sensor. To delay or prevent these changes, it is necessary to limit operation to a temperature sensor structures. The present proposal to incorporate interfacial CeO2 films is based partly on the observation that nanostructured materials in general have potentially useful electrical properties, including an ability to enhance the transfer of electrons. In particular, nanostructured CeO2, that is CeO2 with nanosized grains, has shown promise for incorporation into hightemperature electronic devices. Nanostructured CeO2 films can be formed on SiC and have been shown to exhibit high thermal stability on SiC, characterized by the ability to withstand temperatures somewhat greater than 700 C for limited times. The exchanges of oxygen between CeO2 and SiC prevent the formation of carbon and other chemical species that are unfavorable for operation of a SiC-based Schottky diode as a chemical sensor. Consequently, it is anticipated that in a Pd/CeO2/SiC Schottky

  9. Cooperative effects in CeCu2Si2

    International Nuclear Information System (INIS)

    Lang, M.; Modler, R.; Ahlheim, U.; Helfrich, R.; Reinders, P.H.P.; Steglich, F.; Assmus, W.; Sun, W.; Bruls, G.; Weber, D.; Luethi, B.

    1991-01-01

    Heavy-fermion superconductivity and other cooperative effects have been explored by thermal expansion, specific heat and ultrasound measurements on CeCu 2 Si 2 single crystals. Crystals annealed under Cu atmosphere show sharp superconducting transitions at Tc max =0.63 K. At the same temperature the ''as grown'', i.e., non-bulk-superconducting, crystals reveal a pronounced phase-transition anomaly, presumably of structural origin. This new transition is associated with an expansion of the volume upon cooling and gives rise to magnetic correlations. Our results indicate a complex interplay between lattice instability, magnetic phenomena and superconductivity in CeCu 2 Si 2 . (orig.)

  10. Magnetic Phase Transitions of CeSb. I

    DEFF Research Database (Denmark)

    Fischer, Pernille Hertz; Lebech, Bente; Meier, G.

    1978-01-01

    The magnetic ordering of the anomalous antiferromagnet CeSb, which has a NaCl crystal structure, was determined in zero applied magnetic field by means of neutron diffraction investigations of single crystals and powder. Below the Neel temperature TN of (16.1+or-0.1)K, there exist six partially...... a first-order phase transition at TN. At approximately TN/2 there is a first-order phase transition to a FCC type IA low-temperature configuration. The unusual magnetic properties of CeSb, which result from anisotropic exchange and crystalline electric field effects, resemble those of certain actinide Na...

  11. Isolation and functional characterization of CE1 binding proteins

    Directory of Open Access Journals (Sweden)

    Yu Ji-hyun

    2010-12-01

    Full Text Available Abstract Background Abscisic acid (ABA is a plant hormone that controls seed germination, protective responses to various abiotic stresses and seed maturation. The ABA-dependent processes entail changes in gene expression. Numerous genes are regulated by ABA, and promoter analyses of the genes revealed that cis-elements sharing the ACGTGGC consensus sequence are ubiquitous among ABA-regulated gene promoters. The importance of the core sequence, which is generally known as ABA response element (ABRE, has been demonstrated by various experiments, and its cognate transcription factors known as ABFs/AREBs have been identified. Although necessary, ABRE alone is not sufficient, and another cis-element known as "coupling element (CE" is required for full range ABA-regulation of gene expression. Several CEs are known. However, despite their importance, the cognate transcription factors mediating ABA response via CEs have not been reported to date. Here, we report the isolation of transcription factors that bind one of the coupling elements, CE1. Results To isolate CE1 binding proteins, we carried out yeast one-hybrid screens. Reporter genes containing a trimer of the CE1 element were prepared and introduced into a yeast strain. The yeast was transformed with library DNA that represents RNA isolated from ABA-treated Arabidopsis seedlings. From the screen of 3.6 million yeast transformants, we isolated 78 positive clones. Analysis of the clones revealed that a group of AP2/ERF domain proteins binds the CE1 element. We investigated their expression patterns and analyzed their overexpression lines to investigate the in vivo functions of the CE element binding factors (CEBFs. Here, we show that one of the CEBFs, AtERF13, confers ABA hypersensitivity in Arabidopsis, whereas two other CEBFs enhance sugar sensitivity. Conclusions Our results indicate that a group of AP2/ERF superfamily proteins interacts with CE1. Several CEBFs are known to mediate defense or

  12. Isolation and functional characterization of CE1 binding proteins.

    Science.gov (United States)

    Lee, Sun-ji; Park, Ji Hye; Lee, Mi Hun; Yu, Ji-hyun; Kim, Soo Young

    2010-12-16

    Abscisic acid (ABA) is a plant hormone that controls seed germination, protective responses to various abiotic stresses and seed maturation. The ABA-dependent processes entail changes in gene expression. Numerous genes are regulated by ABA, and promoter analyses of the genes revealed that cis-elements sharing the ACGTGGC consensus sequence are ubiquitous among ABA-regulated gene promoters. The importance of the core sequence, which is generally known as ABA response element (ABRE), has been demonstrated by various experiments, and its cognate transcription factors known as ABFs/AREBs have been identified. Although necessary, ABRE alone is not sufficient, and another cis-element known as "coupling element (CE)" is required for full range ABA-regulation of gene expression. Several CEs are known. However, despite their importance, the cognate transcription factors mediating ABA response via CEs have not been reported to date. Here, we report the isolation of transcription factors that bind one of the coupling elements, CE1. To isolate CE1 binding proteins, we carried out yeast one-hybrid screens. Reporter genes containing a trimer of the CE1 element were prepared and introduced into a yeast strain. The yeast was transformed with library DNA that represents RNA isolated from ABA-treated Arabidopsis seedlings. From the screen of 3.6 million yeast transformants, we isolated 78 positive clones. Analysis of the clones revealed that a group of AP2/ERF domain proteins binds the CE1 element. We investigated their expression patterns and analyzed their overexpression lines to investigate the in vivo functions of the CE element binding factors (CEBFs). Here, we show that one of the CEBFs, AtERF13, confers ABA hypersensitivity in Arabidopsis, whereas two other CEBFs enhance sugar sensitivity. Our results indicate that a group of AP2/ERF superfamily proteins interacts with CE1. Several CEBFs are known to mediate defense or abiotic stress response, but the physiological functions

  13. Investigation into kinetics of redox interaction in the system Ce(4). beta. -diketonate-additional ligand

    Energy Technology Data Exchange (ETDEWEB)

    Anufrieva, S.I.; Snezhko, N.I.; Pechurova, N.I.; Martynenko, L.N.; Spitsyn, V.I. (Moskovskij Gosudarstvennyj Univ. (USSR))

    1981-07-01

    The rate of reduction of ..beta..-diketonate complexes of Ce(4) to Ce(3) ..beta..-diketonates in benzene solution in the presence and in the absence of additional ligands is studied using spectrophotometry. The rate of reduction of Ce(4) ..beta..-diketonates increases in the series Ce(TTFA)/sub 4/<Ce(DPM)/sub 4/<Ce(DBM)/sub 4/<Ce(BA)/sub 4/<Ce(AA)/sub 4/ (TTFA - thenoyltrifluoroacetone, DPM- --dipivaloylmethane, DBM - dibenzoylmethane, BA benzoylacetone, AA - acetylacetone). The studied phosphorus-containing additional ligands as to their effect on the rate of Ce (4) reduction can be arranged in the following order: trioctylphosphine oxide>triphenylphosphine oxide>tributyl phosphate.

  14. Effect of cerium on the corrosion behaviour of sintered (Nd,Ce)FeB magnet

    Science.gov (United States)

    Yang, Lijing; Bi, Mengxue; Jiang, Jianjun; Ding, Xuefeng; Zhu, Minggang; Li, Wei; Lv, Zhongshan; Song, Zhenlun

    2017-06-01

    For the balanced consumption of rare-earth elements, cerium (Ce) was partially used for NdFeB magnets instead of Nd. The corrosion behaviour of the (Nd,Ce)FeB magnet with different Ce contents in 3.5% NaCl solution was investigated by SEM, XRD, EDS and electrochemical tests. After immersion, the weight loss was calculated and the magnetic properties of the samples were measured. Results showed that Ce affected the corrosion of the (Nd,Ce)FeB magnet. Compared with the NdFeB magnet without Ce but of the same grade as the magnetic energy product, (Nd,Ce)FeB magnet showed better corrosion resistance. With increased Ce content, the corrosion resistances and magnetic properties of (Nd,Ce)FeB magnets were investigated.

  15. Optical spectroscopy and luminescence quenching of LuI3:Ce3+

    International Nuclear Information System (INIS)

    Birowosuto, M.D.; Dorenbos, P.; Haas, J.T.M. de; Eijk, C.W.E. van; Kraemer, K.W.; Guedel, H.U.

    2006-01-01

    Optical spectroscopy of LuI 3 doped with Ce 3+ using ultraviolet and visible light excitation is reported. LuI 3 host excitation and emission and 4f-5d excitation and emission of Ce 3+ are observed. An empirical model based on crystal field splitting was used to estimate the energy of the highest 4f-5d excitation band. The crystal field splitting and centroid shift were compared to those of LuCl 3 :Ce 3+ and LuBr 3 :Ce 3+ . Temperature dependence of X-ray excited luminescence spectra shows thermal quenching, whereas that of the decay curve of Ce 3+ emission excited at the lowest 5d band of Ce 3+ does not indicate the presence of quenching of Ce 3+ emission for temperature below 625K. The quenching in LuI 3 :Ce 3+ therefore occurs before the 5d Ce 3+ emission takes place

  16. Scintillation response of BaF2 and YAlO3:Ce (YAP:Ce) to energetic ions

    International Nuclear Information System (INIS)

    Slunga, E.; Cederwall, B.; Ideguchi, E.; Kerek, A.; Klamra, W.; Marel, J. van der; Novak, D.; Norlin, L.-O.

    2001-01-01

    The scintillation response of BaF 2 and YAP:Ce to protons, α particles, 16 O and 28 Si ions in the 5-30 MeV range has been investigated. The ratio between the fast and slow parts of the scintillator signal for BaF 2 has been used to separate protons, α particles and heavier ions, and the dependence of this ratio on the particle energy has been studied. The time constants and intensities of the two components of the YAP:Ce signal were measured, as were the time constant and intensity of the weak component of the slow part of the BaF 2 signal. Furthermore, the dependence of the light yield on the particle energy has been investigated for both BaF 2 and YAP:Ce

  17. Resistance to {gamma} irradiation of LaBr{sub 3}:Ce and LaCl{sub 3}:Ce single crystals

    Energy Technology Data Exchange (ETDEWEB)

    Normand, S. [CEA-Recherche Technologique, DETECS/SSTM CE Saclay F-91191 Gif Sur Yvette Cedex (France)]. E-mail: stephane.normand@cea.fr; Iltis, A. [Saint-Gobain Crystals, 104 Route de Larchant, 77140 St Pierre les Nemours (France); Bernard, F. [Saint-Gobain Crystals, 104 Route de Larchant, 77140 St Pierre les Nemours (France); Domenech, T. [CEA-Recherche Technologique, DETECS/SSTM CE Saclay F-91191 Gif Sur Yvette Cedex (France); Delacour, P. [CEA-Recherche Technologique, DETECS/SSTM CE Saclay F-91191 Gif Sur Yvette Cedex (France)

    2007-03-11

    LaBr{sub 3}:Ce (Brillance 380) and LaCl{sub 3}:Ce (Brillance 350) both exhibit a very good energy resolution and energy linearity response. They are also more sensitive to {gamma}-rays than NaI(Tl) detectors, due to their higher density. The aim of this work is to determine the behaviour of those new single crystals in comparison with NaI(Tl) under severe {gamma}-ray irradiation. Therefore we have irradiated three 25 by 25 mm cylinder crystals encapsulated in air-tight aluminium housing with {sup 60}Co beam. Crystals were tested as stand-alone material not to test the impact of radiation to our photomultiplier tube (PMT). Only encapsulated crystals (alone, without PMTs) were irradiated during several periods to achieve the final 3.4 kGy integrated dose. Intermediate measurements of {sup 137}Cs spectrum were done in order to evaluate the impact of the dose on the studied crystal performances. The radiation hardness of LaBr{sub 3}:Ce and LaCl{sub 3}:Ce was then compared to NaI(Tl). We show in this paper that up to 3.4 kGy no permanent modification of the energy resolution nor colour change is observed for LaBr{sub 3}:Ce and LaCl{sub 3}:Ce crystals. The light output also seems quite stable. This is in stark contrast with the behaviour of NaI:Tl which exhibits continuously decreasing light output, colour change and worsening of energy resolution for doses above 5 Gy.

  18. Dynamical magnetic response of paramagnetic CeFe-2

    International Nuclear Information System (INIS)

    Rainford, B.D.; McK Paul, D.; Warwick Univ., Coventry

    1988-01-01

    Inelastic neutron scattering has been used to study the energy dependence of the paramagnetic response from CeFe 2 . Our results, when integrated over energy, are in excellent agreement with the polarised neutron experiments of Deportes et al., but the correlation length obtained by fitting the data to a double Lorentzian scattering function is significantly smaller than that derived previously

  19. Magnetic domains and frustration in metallic CePdAl

    Energy Technology Data Exchange (ETDEWEB)

    Lucas, Stefan; Huesges, Zita; Huang, Chien-Lung; Stockert, Oliver [Max Planck Institute CPfS, Dresden (Germany); Fritsch, Veronika; Sakai, Akito [EP 6, Electronic Correlations and Magnetism, University of Augsburg (Germany); Grube, Kai; Taubenheim, Christian; Loehneysen, Hilbert von [Karlsruhe Institute of Technology (Germany)

    2016-07-01

    Magnetic frustration is an exciting topic in condensed matter physics, since it can lead to new ground states of materials, e.g. a spin liquid or spin glass state. Effects of magnetic frustration have been investigated intensively for insulating materials. However, the existence of magnetic frustration in metallic systems is still under debate. CePdAl is a metallic Kondo system, where geometric magnetic frustration arises from the formation of Ce ions on a distorted Kagome lattice. Neutron scattering experiments revealed, that only two thirds of the magnetic Ce moments order antiferromagnetically below T{sub N}=2.7 K, whereas the other third remains mainly disordered. Thermodynamic as well as neutron scattering measurements are presented to verify the existence of partial magnetic frustration in CePdAl. Recently neutron diffraction experiments under magnetic fields applied along two orthogonal directions in the magnetically hard basal plane were performed. They show opposite effects on the magnetic intensity of a selected magnetic domain depending on the field direction with respect to the propagation vector. If this is only an effect of different domain population or also due to a change in magnetic frustration shall be discussed.

  20. CE microchips: an opened gate to food analysis.

    Science.gov (United States)

    Escarpa, Alberto; González, María Cristina; Crevillén, Agustín González; Blasco, Antonio Javier

    2007-03-01

    CE microchips are the first generation of micrototal analysis systems (-TAS) emerging in the miniaturization scene of food analysis. CE microchips for food analysis are fabricated in both glass and polymer materials, such as PDMS and poly(methyl methacrylate) (PMMA), and use simple layouts of simple and double T crosses. Nowadays, the detection route preferred is electrochemical in both, amperometry and conductivity modes, using end-channel and contactless configurations, respectively. Food applications using CE microchips are now emerging since food samples present complex matrices, the selectivity being a very important challenge because the total integration of analytical steps into microchip format is very difficult. As a consequence, the first contributions that have recently appeared in the relevant literature are based primarily on fast separations of analytes of high food significance. These protocols are combined with different strategies to achieve selectivity using a suitable nonextensive sample preparation and/or strategically choosing detection routes. Polyphenolic compounds, amino acids, preservatives, and organic and inorganic ions have been studied using CE microchips. Thus, new and exciting future expectations arise in the domain of food analysis. However, several drawbacks could easily be found and assumed within the miniaturization map.

  1. O- centers in LuAG:Ce,Mg ceramics

    Czech Academy of Sciences Publication Activity Database

    Hu, C.; Liu, S.; Fasoli, M.; Vedda, A.; Nikl, Martin; Feng, X. Q.; Pan, Y.B.

    2015-01-01

    Roč. 9, č. 4 (2015), s. 245-249 ISSN 1862-6254 R&D Projects: GA ČR GAP204/12/0805 Institutional support: RVO:68378271 Keywords : scintillator * hole center * EPR * LuAG * Ce 3+ Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 2.578, year: 2015

  2. CE of phytosiderophores and related metal species in plants.

    Science.gov (United States)

    Xuan, Yue; Scheuermann, Enrico B; Meda, Anderson R; Jacob, Peter; von Wirén, Nicolaus; Weber, Günther

    2007-10-01

    Phytosiderophores (PS) and the closely related substance nicotianamine (NA) are key substances in metal uptake into graminaceous plants. Here, the CE separation of these substances and related metal species is demonstrated. In particular, the three PS 2'-deoxymugineic acid (DMA), mugineic acid (MA), and 3-epi-hydroxymugineic acid (epi-HMA), and NA, are separated using MES/Tris buffer at pH 7.3. Moreover, three Fe(III) species of the different PS are separated without any stability problems, which are often present in chromatographic analyses. Also divalent metal species of Cu, Ni, and Zn with the ligands DMA and NA are separated with the same method. By using a special, zwitterionic CE capillary, even the separation of two isomeric Fe(III) chelates with the ligand ethylenediamine-N,N'-bis(o-hydroxyphenyl)acetic acid (EDDHA) is possible (i.e., meso-Fe(III)-EDDHA and rac-Fe(III)-EDDHA), and for fast separations of NA and respective divalent and trivalent metal species, a polymer CE microchip with suppressed EOF is described. The proposed CE method is applicable to real plant samples, and enables to detect changes of metal species (Cu-DMA, Ni-NA), which are directly correlated to biological processes.

  3. CE-TOF/MS: fundamental concepts, instrumental considerations and applications.

    Science.gov (United States)

    Staub, Aline; Schappler, Julie; Rudaz, Serge; Veuthey, Jean-Luc

    2009-05-01

    This review discusses the fundamental principles of TOF analyzers and covers the great progress that has been made in this area in recent years (i.e. orthogonal acceleration, reflectron). This paper also gives an overview of applications performed by CE coupled to TOF/MS detection. The main domains of interest include the analysis of biomolecules and natural compounds.

  4. Projected shell model study of neutron- deficient 122Ce

    Indian Academy of Sciences (India)

    Projected shell model; band diagram; yrast energies; electromagnetic quan- ... signed to 122Ce by detecting γ-rays in coincidence with evaporated charged particles .... 0.75 from the free nucleon values to account for the core-polarization and ...

  5. Diffusion of hydrogen in Pd-(Ce, Y, B) alloys

    International Nuclear Information System (INIS)

    Sakamoto, Y.; Kaneko, H.; Tsukahara, T.; Hirata, S.

    1987-01-01

    The study has been carried out to determine the diffusivity of hydrogen in Pd alloys containing Ce, Y and B in atom fractions up to θ/sub μ/ = 0.1 by an electrochemical permeation method, and to examine the lattice dilation effect on the diffusivity in these alloys. Ce and Y have been chosen because the solid solubility of both in Pd is about 13 at% in spite of the very large atomic size-factor difference between Pd and the solutes, and thus the expansion of the Pd lattice by Ce and Y is much larger than by Ag. Furthermore, it is of interest that the partial enthalpy of the dissolved hydrogen at infinite dilution ΔH 0 /sub H/ for Ce and Y is much smaller than for Pd. On the other hand, B atom also expands the Pd lattice in a way similar to Y, and sometimes B atoms may dissolve in the octahedral interstitial sites in the same way as hydrogen atoms

  6. Commensurate-commensurate magnetic phase transitions in CeSb

    DEFF Research Database (Denmark)

    Lebech, Bente; Broholm, C.; Clausen, K.

    1986-01-01

    The q=2/3 to q=4/7 commensurate-commensurate phase transition in CeSb has been studied by neutron diffraction. On cooling the commensurate wave vector q changes abruptly from 2/3 to a higher-order commensurate value (≈14/23) at T1

  7. Information System through ANIS at CeSAM

    Science.gov (United States)

    Moreau, C.; Agneray, F.; Gimenez, S.

    2015-09-01

    ANIS (AstroNomical Information System) is a web generic tool developed at CeSAM to facilitate and standardize the implementation of astronomical data of various kinds through private and/or public dedicated Information Systems. The architecture of ANIS is composed of a database server which contains the project data, a web user interface template which provides high level services (search, extract and display imaging and spectroscopic data using a combination of criteria, an object list, a sql query module or a cone search interfaces), a framework composed of several packages, and a metadata database managed by a web administration entity. The process to implement a new ANIS instance at CeSAM is easy and fast : the scientific project has to submit data or a data secure access, the CeSAM team installs the new instance (web interface template and the metadata database), and the project administrator can configure the instance with the web ANIS-administration entity. Currently, the CeSAM offers through ANIS a web access to VO compliant Information Systems for different projects (HeDaM, HST-COSMOS, CFHTLS-ZPhots, ExoDAT,...).

  8. Three-Dimensional Structure of CeO2 Nanocrystals

    DEFF Research Database (Denmark)

    Tan, Joyce Pei Ying; Tan, Hui Ru; Boothroyd, Chris

    2011-01-01

    Visualization of three-dimensional (3D) structures of materials at the nanometer scale can shed important information on the performance of their applications and provide insight into the growth mechanism of shape-controlled nanomaterials. In this paper, the 3D structures and growth pathway of Ce...

  9. A Sesame Equation of State for Dense Ce

    Energy Technology Data Exchange (ETDEWEB)

    Greeff, Carl William [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Crockett, Scott [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-03-15

    We generated a new Sesame equation of state table for Ce. It is a single effective phase table for the high density phases α, α ', ϵ and liquid. Also, the EOS is meant to be used with a ramp to represent the initial low density γ phase.

  10. Magnetic and transport properties of amorphous Ce-Al alloy

    Science.gov (United States)

    Amakai, Yusuke; Murayama, Shigeyuki; Momono, Naoki; Takano, Hideaki; Kuwai, Tomohiko

    2018-05-01

    Amorphous (a-)Ce50Al50 has been prepared by DC high-rate sputter method. The structure of the obtained sample has been confirmed to have an amorphous structure because there are no Bragg peaks in the X-ray diffraction measurement and have a clear exothermic peak by the differential scanning calorimetry measurement. We have measured the resistivity ρ, magnetic susceptibility χ, specific heat Cp and thermoelectric power S for a-Ce50Al50. The temperature dependence of ρ exhibits a small temperature dependence less than 10% in the whole temperature region. χ follows a Curie-Weiss behavior in the high-temperature region of T>90 K. The effective paramagnetic moment peff, estimated from C is 2.18 μB/Ce-atom. The low-temperature Cp/T increases rapidly with decreasing temperature and tends to a saturation. S(T) exhibits negative values in a wide temperature region. A minimum of S appear at around 60 K, and S decreases linearly with decreasing temperature down to 10 K. The low-temperature S is almost 0 μV/K down to 2 K. From these results, we have pointed out that present a-Ce50Al50 would be an incoherent Kondo material.

  11. Implementace OpenVPN na platformě Windows CE

    OpenAIRE

    Ešner, Oldřich

    2008-01-01

    Motivací pro vznik této diplomové práce, která navazuje na stejnojmenný semestrální projekt, byl převod aplikace pro tvorbu virtuálních privátních sítí OpenVPN z operačního systému Windows XP na platformu Windows CE Embedded 6.0. Práce pojednává obecně o virtuálních privátních sítích, a podrobněji o jedné z jejich implementací - OpenVPN. Uvádí základní vlastnosti operačního systému Windows CE, dále popisuje princip ovladačů zařízení v operačních systémech na bázi Windows NT, používaný Windows...

  12. Preparation and properties of Pr /Ce :YAG phosphors using ...

    Indian Academy of Sciences (India)

    2015-09-01

    Sep 1, 2015 ... [3] transparent ceramics for high power solid-state lasers and Ce:YAG ... and CO2−. 3 . ... be controlled to guarantee that all the metal ions are simul- taneously .... of hydrogen bonding interaction can lead to more serious.

  13. Itinerant magnetism in CeRh3B2

    DEFF Research Database (Denmark)

    Eriksson, Olle; Johansson, Börje; Brooks, M. S. S.

    1989-01-01

    Spin-polarized energy-band calculations, including spin-orbit coupling in the band Hamiltonian, have been performed on CeRh3B2. Good agreement is obtained between theory and experiment concerning the magnetic moment. It is also found that the magnetic moment varies strongly with volume and from...

  14. Estimation of bulk transfer coefficient for latent heat flux (Ce)

    Digital Repository Service at National Institute of Oceanography (India)

    Sadhuram, Y.

    The bulk transfer coefficient for latent heat flux (Ce) has been estimated over the Arabian Sea from the moisture budget during the pre-monsoon season of 1988. The computations have been made over two regions (A: 0-8 degrees N: 60-68 degrees E: B: 0...

  15. Geometry modeling for SAM-CE Monte Carlo calculations

    International Nuclear Information System (INIS)

    Steinberg, H.A.; Troubetzkoy, E.S.

    1980-01-01

    Three geometry packages have been developed and incorporated into SAM-CE, for representing in three dimensions the transport medium. These are combinatorial geometry - a general (non-lattice) system, complex combinatorial geometry - a very general system with lattice capability, and special reactor geometry - a special purpose system for light water reactor geometries. Their different attributes are described

  16. Heat capacity measurement of CeNbO4(s)

    International Nuclear Information System (INIS)

    Bhojane, S.M.; Kulkarni, Jayanthi; Kulkarni, S.G.

    2012-01-01

    Molar heat capacity of CeNbO 4 (s) was determined using differential scanning calorimeter in the temperature range of 550 to 900 K. The molar heat capacity values were least squares analysed and the dependence of molar heat capacity with temperature for CeNbO 4 (s) can be given as, J K -1 mol -1 = 94.7320 + 0.0852T-1.6073 x 10 6 T -2 (550≤T(K)≤900) Cerium is commonly used as an inactive analogue to plutonium; also it is an important fission product with moderate yield. Various Nb alloys are used as cladding material in nuclear industry. Hosts of thermodynamic data are needed to understand the various phenomena that occur in a nuclear reactor. In the present study, the molar heat capacity of CeNbO 4 (s) has been determined using high temperature differential scanning calorimeter in temperature range 550 to 900 K. This is one of the important compounds in the ternary system of Ce-Nb-O

  17. Ciclo combinado Diesel-Vapor como repotenciación de una central termoeléctrica: caso de estudio; Combined Cycle Diesel-Steam as Power Plant Repowering: study case

    Directory of Open Access Journals (Sweden)

    Alberto Eduardo Calvo González

    2015-04-01

    Full Text Available La necesidad imperiosa de cubrir el déficit de generación eléctrica ampliando el potencial de generación con motores diesel a fuel oíl, cuya instalación requiere de muy poco tiempo, es una solución adecuada. La idea de aprovechar los nodos del sistema electro energético, como son las subestaciones y las centrales eléctricas, para instalar los grupos electrógenos es una solución apropiada. Pero en el caso de una central termoeléctrica, al montar estas instalaciones de forma independiente, no se aprovechan las posibilidades que la combinación de procesos ofrece como la disminución del consumo de combustible, y de la contaminación ambiental por unidad de energía producida. El presente trabajo explora la posibilidad de instalar plantas eléctricas diesel a fuel oil como ciclo combinado diesel-vapor. Se demuestra la conveniencia de instalar plantas eléctricas diesel a fuel oil como ciclo combinado diesel-vapor, aprovechando la sinergia que se logra por la combinación de los procesos térmicos.  The pressing need of covering generation deficit to satisfy the demand in the shorter possible time, by enlarging the generation potential with fuel oil fueled diesel motors, it’s an appropriate solution. The idea of taking advantage of electric grid existent nodes facilities to place the generating electricity diesel motors is a non-unwise solution. But in the case of the node of steam power station place these motors in an independent way, don't take advantage of the possibilities that the processes combination offers, as the combined cycle diesel vapor for example. The work presented herein explored and showed the possibility of installing the electric diesel plants as a repowering the existing steam power plant by combined cycle diesel-steam taking advantage of the synergy achieved by thermal processes combination.

  18. Ciclo combinado Diesel-Vapor como repotenciación de una central termoeléctrica: caso de estudio; Combined Cycle Diesel-Steam as Power Plant Repowering: study case

    Directory of Open Access Journals (Sweden)

    Alberto Eduardo Calvo González

    2014-06-01

    Full Text Available La necesidad imperiosa de cubrir el déficit de generación eléctrica ampliando el potencial de generación con motores diesel a fuel oíl, cuya instalación requiere de muy poco tiempo, es una solución adecuada. La idea de aprovechar los nodos del sistema electro energético, como son las subestaciones y las centrales eléctricas, para instalar los grupos electrógenos es una solución apropiada. Pero en el caso de una central termoeléctrica, al montar estas instalaciones de forma independiente, no se aprovechan las posibilidades que la combinación de procesos ofrece como la disminución del consumo de combustible, y de la contaminación ambiental por unidad de energía producida. El presente trabajo explora la posibilidad de instalar plantas eléctricas diesel a fuel oil como ciclo combinado diesel-vapor. Se demuestra la conveniencia de instalar plantas eléctricas diesel a fuel oil como ciclo combinado diesel-vapor, aprovechando la sinergia que se logra por la combinación de los procesos térmicos. The pressing need of covering generation deficit to satisfy the demand in the shorter possible time, by enlarging the generation potential with fuel oil fueled diesel motors, it’s an appropriate solution. The idea of taking advantage of electric grid existent nodes facilities to place the generating electricity diesel motors is a non-unwise solution. But in the case of the node of steam power station place these motors in an independent way, don't take advantage of the possibilities that the processes combination offers, as the combined cycle diesel vapor for example. The work presented herein explored and showed the possibility of installing the electric diesel plants as a repowering the existing steam power plant by combined cycle diesel-steam taking advantage of the synergy achieved by thermal processes combination.

  19. Synthesis, extraction and electronic structure of Ce@C2n

    Science.gov (United States)

    Liu, Bing-Bing; Zou, Guang-Tian; Yang, Hai-Bin; Yu, San; Lu, Jin-Shan; Liu, Zi-Yang; Liu, Shu-Ying; Xu, Wen-Guo

    1997-11-01

    In view of the growing interest in endohedral lanthanide fullerenes, Ce, as a typical+ 4 oxidation state lanthanide element, has been systematically studied. The synthesis, extraction and electronic structure of Ce @ C2n are investigated. Soot containing Ce@C2n was synthesized in high yield by carbonizing CeO2-containing graphite rods and are back-burning the CeC2-enriched cathode deposit in a DC arc plasma apparatus. Ce@C2n dominated by Ce@C82, can be efficiently extracted from the insoluble part of the soot after toluene Soxhlet extraction by pyridine at high temperature and high pressure in a closed vessel. About 60% Ce@C2n(2n = 82, 80, 78, 76) and 35% Ce@C82 can be enriched in the pyridine extract. This fact is identified by desorption electron impact mass spectrometry (DEI MS). The electronic structure of Ce@C2n is analyzed by using X-ray photoemission spectroscopy (XPS) of pyridine-free film. It is suggested that the encapsulated Ce atom is in a charge state close to+ 3 and was effectively protected from reaction with water and oxygen by the enclosing fullerene cage. Unlike theoretical expectation, the electronic state of Ce@C82 is formally described as Ce+3@C3-82.

  20. Oxidative Ce"3"+ sequestration by fungal manganese oxides with an associated Mn(II) oxidase activity

    International Nuclear Information System (INIS)

    Zheng, Haisu; Tani, Yukinori; Naitou, Hirotaka; Miyata, Naoyuki; Tojo, Fuyumi

    2016-01-01

    Sequestration of Ce"3"+ by biogenic manganese oxides (BMOs) formed by a Mn(II)-oxidizing fungus, Acremonium strictum strain KR21-2, was examined at pH 6.0. In anaerobic Ce"3"+ solution, newly formed BMOs exhibited stoichiometric Ce"3"+ oxidation, where the molar ratio of Ce"3"+ sequestered (Ce_s_e_q) relative to Mn"2"+ released (Mn_r_e_l) was maintained at approximately two throughout the reaction. A similar Ce"3"+ sequestration trend was observed in anaerobic treatment of BMOs in which the associated Mn(II) oxidase was completely inactivated by heating at 85 °C for 1 h or by adding 50 mM NaN_3. Aerobic Ce"3"+ treatment of newly formed BMO (enzymatically active) resulted in excessive Ce"3"+ sequestration over Mn"2"+ release, yielding Ce_s_e_q/Mn_r_e_l > 200, whereas heated or poisoned BMOs released a significant amount of Mn"2"+ with lower Ce"3"+ sequestration efficiency. Consequently, self-regeneration by the Mn(II) oxidase in newly formed BMO effectively suppressed Mn"2"+ release and enhanced oxidative Ce"3"+ sequestration under aerobic conditions. Repeated treatments of heated or poisoned BMOs under aerobic conditions confirmed that oxidative Ce"3"+ sequestration continued even after most Mn oxide was released from the solid phase, indicating auto-catalytic Ce"3"+ oxidation at the solid phase produced through primary Ce"3"+ oxidation by BMO. From X-ray diffraction analysis, the resultant solid phases formed through Ce"3"+ oxidation by BMO under both aerobic and anaerobic conditions consisted of cerianite with crystal sizes of 5.00–7.23 Å. Such nano-sized CeO_2 (CeO_2_,_B_M_O) showed faster auto-catalytic Ce"3"+ oxidation than that on well-crystalized cerianite under aerobic conditions, where the normalized pseudo-first order rate constants for auto-catalytic Ce"3"+ oxidation on CeO_2_,_B_M_O was two orders of magnitude higher. Consequently, we concluded that Ce"3"+ contact with BMOs sequesters Ce"3"+ through two oxidation paths: primary Ce"3

  1. The equiatomic intermetallics REPtCd (RE = La, Ce, Pr, Nd, Eu) and magnetic properties of CeAuCd

    Energy Technology Data Exchange (ETDEWEB)

    Johnscher, Michael; Niehaus, Oliver; Poettgen, Rainer [Muenster Univ. (Germany). Inst. fuer Anorganische und Analytische Chemie; Tappe, Frank [Hochschule Hamm-Lippstadt, Hamm (Germany)

    2015-06-01

    The cadmium intermetallics REPtCd (RE = La, Ce, Pr, Nd, Eu) and CeAuCd were synthesized by induction-melting of the elements in sealed niobium ampoules followed by annealing in muffle furnaces. The samples were characterized by powder X-ray diffraction. The structures of CePtCd (ZrNiAl type, P anti 62m, a = 763.8(6), c = 409.1(4) pm, wR2 = 0.0195, 298 F{sup 2} values, 14 variables) and EuPtCd (TiNiSi type, Pnma, a = 741.3(2), b = 436.4(1), c = 858.0(4) pm, wR2 = 0.0385, 440 F{sup 2} values, 20 variables) were refined from single-crystal data. The REPtCd structures exhibit three-dimensional networks of corner- and edge-sharing Cd rate at Pt{sub 2/6}Pt{sub 2/3} and Cd rate at Pt{sub 4/4} tetrahedra, which leave cages for the rare earth atoms. Temperature-dependent magnetic susceptibility data of CeAuCd reveal a paramagnetic to antiferromagnetic phase transition at T{sub N} = 3.7(5) K.

  2. The equiatomic intermetallics REPtCd (RE = La, Ce, Pr, Nd, Eu) and magnetic properties of CeAuCd

    International Nuclear Information System (INIS)

    Johnscher, Michael; Niehaus, Oliver; Poettgen, Rainer

    2015-01-01

    The cadmium intermetallics REPtCd (RE = La, Ce, Pr, Nd, Eu) and CeAuCd were synthesized by induction-melting of the elements in sealed niobium ampoules followed by annealing in muffle furnaces. The samples were characterized by powder X-ray diffraction. The structures of CePtCd (ZrNiAl type, P anti 62m, a = 763.8(6), c = 409.1(4) pm, wR2 = 0.0195, 298 F 2 values, 14 variables) and EuPtCd (TiNiSi type, Pnma, a = 741.3(2), b = 436.4(1), c = 858.0(4) pm, wR2 = 0.0385, 440 F 2 values, 20 variables) were refined from single-crystal data. The REPtCd structures exhibit three-dimensional networks of corner- and edge-sharing Cd rate at Pt 2/6 Pt 2/3 and Cd rate at Pt 4/4 tetrahedra, which leave cages for the rare earth atoms. Temperature-dependent magnetic susceptibility data of CeAuCd reveal a paramagnetic to antiferromagnetic phase transition at T N = 3.7(5) K.

  3. Crystal growth and scintillation properties of multi-component oxide single crystals: Ce:GGAG and Ce:La-GPS

    Czech Academy of Sciences Publication Activity Database

    Yoshikawa, A.; Kamada, K.; Kurosawa, S.; Shoji, Y.; Yokota, Y.; Chani, V.I.; Nikl, Martin

    2016-01-01

    Roč. 169, Jan (2016), s. 387-393 ISSN 0022-2313. [International Conference on Luminescence and Optical Spectroscopy of Condensed Matter /17./. Wroclaw, 13.07.2014-18.07.2014] Institutional support: RVO:68378271 Keywords : scintillator * luminescent materials * Ce 3+ * radioluminescence Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 2.686, year: 2016

  4. Ethanol Sensor of CdO/Al2O3/CeO2 Obtained from Ce-DOPED Layered Double Hydroxides with High Response and Selectivity

    Science.gov (United States)

    Xu, Dongmei; Guan, Meiyu; Xu, Qinghong; Guo, Ying; Wang, Yao

    2013-04-01

    In this paper, Ce-doped CdAl layered double hydroxide (LDH) was first synthesized and the derivative CdO/Al2O3/CeO2 composite oxide was prepared by calcining Ce-doped CdAl LDH. The structure, morphology and chemical state of the Ce doped CdAl LDH and CdO/Al2O3/CeO2 were also investigated by X-ray diffraction (XRD), Fourier transform infrared (FT-IR), solid state nuclear magnetic resonance (SSNMR), scanning electron microscope (SEM) and X-ray photoelectron spectroscopy (XPS). The gas sensing properties of CdO/Al2O3/CeO2 to ethanol were further studied and compared with CdO/Al2O3 prepared from CdAl LDH, CeO2 powder as well as the calcined Ce salt. It turns out that CdO/Al2O3/CeO2 sensor shows best performance in ethanol response. Besides, CdO/Al2O3/CeO2 possesses short response/recovery time (12/72 s) as well as remarkable selectivity in ethanol sensing, which means composite oxides prepared from LDH are very promising in gas sensing application.

  5. A facile synthesis for cauliflower like CeO2 catalysts from Ce-BTC precursor and their catalytic performance for CO oxidation

    Science.gov (United States)

    Zhang, Xiaodong; Hou, Fulin; Yang, Yang; Wang, Yuxin; Liu, Ning; Chen, Dan; Yang, Yiqiong

    2017-11-01

    The paper presents a novel and facile method for preparing cauliflowerlike CeO2 through direct decomposition of cerium based metal-organic framework (MOF) Ce-BTC (BTC = 1,3,5-benzenetricarboxylic acid) straw in air. Several analytical tools such as Scanning electron microscopy (SEM), X-ray diffraction (XRD), Thermogravimetric (TG), N2 adsorption-desorption, Temperature programmed reduction (TPR), Raman, X-ray photoelectron spectroscopic (XPS) and Photoluminescence (PL) have been used to characterize Ce-BTC and CeO2. The Ce-BTC calcined at 500 °C (CeO2-500) maintains the morphology of its template ;Ce-BTC; and forms a special cauliflower-like structure. XRD patterns showed that the catalyst has a perfect CeO2 crystal structure and has a smaller particle size. The prepared CeO2 cauliflowers exhibit excellent catalytic activities, long-term stability, and cycling stability for CO oxidation. The improved catalytic activities could be attributed to porous nanorods of CeO2 cauliflowers, which provide more active sites and oxygen vacancy for CO oxidation.

  6. Toxicity of inhaled 144CeCl3 in beagle dogs

    International Nuclear Information System (INIS)

    Muggenburg, B.A.; Hahn, F.F.; Boecker, B.B.; McClellan, R.O.; Pickrell, J.A.

    1980-01-01

    The metabolism, dosimetry and effects of inhaled 144 CeCl 3 in beagle dogs are being studied to assess the biological consequences of inhaling 144 Ce. Studies have shown that the 144 Ce deposited in the lung as 144 CeCl 3 is translocated at a moderately rapid rate to liver and skeleton and that significant radiation doses are accumulated by all three organs. Fifty-five dogs that inhaled 144 CeCl 3 and 17 control dogs are being observed for their life span. The 144 Ce-exposed dogs had long-term retained burdens that ranged from 2.6 to 360 μCi 144 Ce/kg body weight. Fifty-three of the dogs exposed to 144 CeCl 3 have died and twelve control dogs have died. Serial observations are continuing on the two surviving exposed dogs and five control dogs

  7. Effect of Ce on performance and physicochemical properties of Pt-containing automotive emission control catalysts

    International Nuclear Information System (INIS)

    Nunan, J.G.; Silver, R.G.; Bradley, S.A.

    1992-01-01

    Present-day automotive emission control catalysts contain noble metals such as Pt, Pd and Rh all on an alumina support with a variety of promoters. Ce is one of the most important promoters. In this paper, the interaction between Pt and Ce is studied using TPR and STEM on a variety of catalysts. The degree of Pt/Ce interaction is increased by decreasing CeO 2 crystallite size, and to a lesser extent by increasing CeO 2 loading. Direct Pt/Ce interaction leads to a synergistic reduction of both Pt and surface Ce. This reduction qualitatively correlates with catalyst performance after activation in a reducing gas. It is proposed that this synergistic reduction of Pt and Ce is associated with observed improvements in catalyst performance using a non-oscillating exhaust gas

  8. Anisotropic p-f mixing mechanism explaining anomalous magnetic properties in Ce monopnictides

    International Nuclear Information System (INIS)

    Takahashi, H.; Kasuya, T.

    1985-01-01

    An anomalously small crystal-field splitting in the paramagnetic region in CeSb and CeBi compared with those in CeP and CeAs is explained by the mixing mechanism between the occupied 4f states and the valence band holes. In the paramagnetic regions, the above p-f mixing gives the effective crystal-field splitting, which is estimated to nearly cancel the normal splittings extrapolated from CeP and CeAs in good agreement with experiment. The formula for the second-order transition temperature, at which the population ratio of the 4f GAMMA 8 states begins to be unbalanced, is also derived. In CeBi the second-order transition may occur, while in CeSb the first-order transition should occur in agreement with experiments. (author)

  9. Fermi-surface topology of the heavy-fermion system Ce2PtIn8

    Science.gov (United States)

    Klotz, J.; Götze, K.; Green, E. L.; Demuer, A.; Shishido, H.; Ishida, T.; Harima, H.; Wosnitza, J.; Sheikin, I.

    2018-04-01

    Ce2PtIn8 is a recently discovered heavy-fermion system structurally related to the well-studied superconductor CeCoIn5. Here we report on low-temperature de Haas-van Alphen-effect measurements in high magnetic fields in Ce2PtIn8 and Pr2PtIn8 . In addition, we performed band-structure calculations for localized and itinerant Ce-4 f electrons in Ce2PtIn8 . Comparison with the experimental data of Ce2PtIn8 and of the 4 f -localized Pr2PtIn8 suggests the itinerant character of the Ce-4 f electrons. This conclusion is further supported by the observation of effective masses in Ce2PtIn8 , which are strongly enhanced with up to 26 bare electron masses.

  10. Down-conversion luminescence from (Ce, Yb) co-doped oxygen-rich silicon oxides

    International Nuclear Information System (INIS)

    Heng, C. L.; Wang, T.; Su, W. Y.; Wu, H. C.; Yin, P. G.; Finstad, T. G.

    2016-01-01

    We have studied down-conversion photoluminescence (PL) from (Ce, Yb) co-doped “oxygen rich” silicon oxide films prepared by sputtering and annealing. The Ce"3"+ ∼510 nm PL is sensitive to the Ce concentration of the films and is much stronger for 3 at. % Ce than for 2 at. % Ce after annealing at 1200 °C. The PL emission and excitation spectroscopy results indicate that the excitation of Yb"3"+ is mainly through an energy transfer from Ce"3"+ to Yb"3"+, oxide defects also play a role in the excitation of Yb"3"+ after lower temperature (∼800 °C) annealing. The Ce"3"+ 510 nm photon excites mostly only one Yb"3"+ 980 nm photon. Temperature-dependent PL measurements suggest that the energy transfer from Ce"3"+ to Yb"3"+ is partly thermally activated.

  11. The investigation of Ce doped ZnO crystal: The electronic, optical and magnetic properties

    Science.gov (United States)

    Wen, Jun-Qing; Zhang, Jian-Min; Qiu, Ze-Gang; Yang, Xu; Li, Zhi-Qin

    2018-04-01

    The electronic, optical and magnetic properties of Ce doped ZnO crystal have been studied by using first principles method. The research of formation energies show that Ce doped ZnO is energetically stable, and the formation energies reduce from 6.25% to 12.5% for Ce molar percentage. The energy band is still direct band gap after Ce doped, and band gap increases with the increase of Cesbnd Ce distance. The Fermi level moves upward into conduction band and the DOS moves to lower energy with the increase of Ce concentration, which showing the properties of n-type semiconductor. The calculated optical properties imply that Ce doped causes a red-shift of absorption peaks, and enhances the absorption of the visible light. The transition from ferromagnetic to antiferromagnetic has been found in Ce doped ZnO.

  12. Myxomycetes da Chapada do Araripe (Crato - CE, Brasil Myxomycetes from Chapada do Araripe (Crato, CE, Brazil

    Directory of Open Access Journals (Sweden)

    Laise de Holanda Cavalcanti

    1998-12-01

    Full Text Available Foi efetuado um levantamento dos Myxomyeetes ocorrentes em área de floresta no município do Crato, CE (7º13'53" S; 39º24'28'' W; Alt. 422m, assinalando-se as seguintes famílias e gêneros: Ceratiomyxaceae (Ceratiomyxa, 1 sp.; Cribrariaceae (Cribraria, lsp., Dictydium, 1 sp.; Didymiaceae (Didymium, 2sp.; Enteridiaceae (Dicrydiaethalium, 1sp.; Physaraceae (Badhamia, 2sp., Fuligo, 2sp., Physarum, 5sp.; Steinonitaceae (Comatricha, 3sp., Sfemonitis, 6sp.; Trichiaceae (Arcyria, 3sp., Hemitrichia, 2sp., Periclwena, 1 sp.- Constatou-se preferência das espécies para frutificar em troncos mortos de dicotiledôneas, seguindo-se restos de palmeiras e folhedo. O levantamento eleva para 30 o número de espécies referidas para o Ceará. Uma família e 19 espécies são novos registros para o Estado e Arcyria magna var. rosea Rex é nova referência para o Brasil. São apresentados comentários, chave de identificação e distribuição geográfica das espécies no Nordeste do Brasil.A survey on Myxomycetes was made in the woods of Crato Municipality. State of Ceará, Brazil (7º13'53" S; 39º24,28" W; Alt. 422m. when the following families and genera were registered: Ceratiomyxaceae (Ceratiomyxa, 1 sp.; Cribrariaceae (Cribraria, 1 sp., Dictydium. 1 sp.; Didymiaceae (Didymium, 2sp.; Enteridiaceae Dictydiaethalium, 1 sp.; Physaraceae (Badhamia. 2sp., Fuligo, 2sp., Physarum, 5sp.; Stemonitaceae Comatricha, 3sp., Stemonitis, 6sp.; Trichiaceae (Arcyria, 3sp., Hemitrichia, 2sp., Perichaena, lsp..The species sporulated mostly on dead dicotyledones wood, followed by monocotyledones (Arecaceae debris and litter. The survey raises the number of registers referred to the State of Ceará to 30 species. One family and 19 species are new records for that State while Arcyria magna var. rosea Rex represents a new record for Brazil. Key for the species, comments and geographical distribution in Northeast Brazil arc presented.

  13. Redox behavior of Ce(IV)/Ce(III) in the presence of nitrilotriacetic acid: a surrogate study for An(IV)/An(III) redox behavior

    International Nuclear Information System (INIS)

    Suzuki, Y.; Nankawa, T.; Ohnuki, T.; Francis, A.J.

    2010-01-01

    Using cyclic voltammetry, we investigated the redox behavior of Ce(IV)/Ce(III), which is a surrogate for An(IV)/An(III) (An = actinides), in a solution of nitrilotriacetic acid (NTA) at 25 C. The cyclic voltammogram of Ce in a 0.1 M NTA solution at pH 6 showed a reversible one-electron redox reaction for Ce(IV)/Ce(III) at 0.51 V vs. Ag/AgCl. This redox potential was much lower than that obtained in 1 M nitric acid, indicating that Ce(IV) was preferentially stabilized by complexation with NTA. The redox potential in the NTA solution was independent of the Ce concentration from 2 to 20 mM, NTA concentration from 5 to 200 mM and pH between 3 and 7. These results indicated that no polymerization and no additional coordination of NTA and OH to the Ce(III)-NTA complex took place during the redox reaction. As the speciation calculation of Ce(III) in the NTA solution showed that the predominant species was Ce III (nta) 2 3 (H 3 nta = NTA), the redox reaction of the Ce-NTA complex was expressed by the following: Ce IV (nta) 2 2- + e - ↔ Ce III (nta) 2 3 . The logarithm of the stability constant of Ce IV (nta) 2 2- was calculated to be 38.6 ± 0.8 for I = 0 from the redox potential shift of Ce(IV)/Ce(III) in the NTA solution. The value was in good accordance with the stability constant of the Np IV (nta) 2 2- complex, demonstrating that the aqueous coordination chemistry of Ce(IV) with NTA is quite similar to that of An(IV). These results strongly suggest that a negative shift of the Pu(IV)/Pu(III) redox potential in the NTA solution should make Pu(IV) more stable than Pu(III) even in a reducing environment. (orig.)

  14. Pre-Feasibility Analysis of Pellet Manufacturing on the Former Loring Air Force Base Site. A Study Prepared in Partnership with the Environmental Protection Agency for the RE-Powering America's Land Initiative: Siting Renewable Energy on Potentially Contaminated Land and Mine Sites

    Energy Technology Data Exchange (ETDEWEB)

    Hunsberger, R.; Mosey, G.

    2014-04-01

    The U.S. Environmental Protection Agency (EPA) Office of Solid Waste and Emergency Response, in accordance with the RE-Powering America's Lands initiative, engaged the U.S. Department of Energy's (DOE) National Renewable Energy Laboratory (NREL) to conduct feasibility studies to assess the viability of developing renewable energy generating facilities on contaminated sites. This site, in Limestone, Maine -- formerly the location of the Loring Air Force Base but now owned by the Aroostook Band of Micmac -- was selected for the potential to produce heating pellets from woody feedstock. Biomass was chosen as the renewable energy resource to evaluate based on abundant woody-biomass resources available in the area. NREL also evaluates potential savings from converting existing Micmac property from oil-fired heating to pellet heating.

  15. Structure and phase composition of Al-Ce-Cu system alloys in range of quasi-binary Al-Al8CeCu4 section

    International Nuclear Information System (INIS)

    Belov, N.A.; Khvan, A.V.

    2007-01-01

    The phase diagram of the Al-Cu-Ce system in the quasibinary section area of Al-Al 8 CeCu 4 has been investigated by metallographic, thermal, micro-X-ray spectral and X-ray structural analyses. The parameters of the eutectic reaction L→(Al)+CeCu 4 Al 8 : T=610 Deg C were found out; the composition was 14% Cu and 7% Ce. This eutectics is of a disperse structure and the ternary compound contained is capable of fragmentation and spheroidizing in the heating process (starting from 540 Deg C). It was demonstrated that the area of optimal (Al)+CeCu 4 Al 8 eutectics-based alloy compositions was within the narrow limits. That is related to the fact that at a comparatively little variation of the Cu:Ce=2 ratio solidus sharply decreases and, as a result, the crystallization interval considerably extends [ru

  16. Luminescence and Tb3+-Ce3+-Eu3+ ion energy transfer in single-crystalline films of Tb3Al5O12:Ce,Eu garnet

    International Nuclear Information System (INIS)

    Zorenko, Y.; Gorbenko, V.; Voznyak, T.; Batentschuk, M.; Osvet, A.; Winnacker, A.

    2008-01-01

    The paper is devoted to investigation of the processes of excitation energy transfer between the host cations (Tb 3+ ions) and the activators (Ce 3+ and Eu 3+ ions) in single-crystalline films of Tb 3 Al 5 O 12 :Ce,Eu (TbAG:Ce,Eu) garnet which is considered as a promising luminescent material for the conversion of LED's radiation. The cascade process of excitation energy transfer is shown to be realized in TbAG:Ce,Eu: (i) from Tb 3+ ions to Ce 3+ and Eu 3+ ions; (ii) from Ce 3+ ions to Eu 3+ ions by means of dipole-dipole interaction and through Tb 3+ ion sublattice

  17. Heteroaggregation, transformation and fate of CeO2 nanoparticles in wastewater treatment

    International Nuclear Information System (INIS)

    Barton, Lauren E.; Auffan, Melanie; Olivi, Luca; Bottero, Jean-Yves; Wiesner, Mark R.

    2015-01-01

    Wastewater Treatment Plants (WWTPs) are a key pathway by which nanoparticles (NPs) enter the environment following release from NP-enabled products. This work considers the fate and exposure of CeO 2 NPs in WWTPs in a two-step process of heteroaggregation with bacteria followed by the subsequent reduction of Ce(IV) to Ce(III). Measurements of NP association with solids in sludge were combined with experimental estimates of reduction rate constants for CeO 2 NPs in Monte Carlo simulations to predict the concentrations and speciation of Ce in WWTP effluents and biosolids. Experiments indicated preferential accumulation of CeO 2 NPs in biosolids where reductive transformation would occur. Surface functionalization was observed to impact both the distribution coefficient and the rates of transformation. The relative affinity of CeO 2 NPs for bacterial suspensions in sludge appears to explain differences in the observed rates of Ce reduction for the two types of CeO 2 NPs studied. - Highlights: • We combine experimental and computational methods to track CeO 2 NPs through WWTPs. • We investigate the importance of environmental transformations on NP exposure. • We estimate the concentrations of CeO 2 NPs and reductive transformation byproducts. - CeO 2 nanoparticles that are released to the waste stream will preferentially associate with the solid phase (∼96%), where they will undergo significant transformation (∼50%)

  18. Homogeneously dispersed CeO2 nanoparticles on exfoliated hexaniobate nanosheets

    Science.gov (United States)

    Marques, Thalles M. F.; Strayer, Megan E.; Ghosh, Anupama; Silva, Alexandre; Ferreira, Odair P.; Fujisawa, Kazunori; Alves da Cunha, Jose R.; Abreu, Guilherme J. P.; Terrones, Mauricio; Mallouk, Thomas E.; Viana, Bartolomeu C.

    2017-12-01

    Hexaniobate nanosheets derived from the parent compound K4Nb6O17 have been decorated with CeO2 nanoparticles by ion exchange with aqueous cerium (IV) solution. Very homogeneous CeO2 nanoparticle decoration of the hexaniobate sheets can be achieved by this method and the resulting composites may absorb visible light. HRTEM images show that ∼3.0 nm diameter CeO2 nanoparticles adhere to hexaniobate nanosheets that are exfoliated and then restacked prior to Ce deposition. The interfacial interaction between CeO2 nanoparticles and nanosheets would be due to an electrostatic attraction mechanism. Raman and XRD measurements have given strong evidence that CeO2 nanoparticles have fluorite structure. EDS, FTIR and XPS results suggest almost complete exchange of TBA+ and K+ by Ce4+. Cerium ion exchange on the acid exchanged parent compound, H2.9K1.1Nb6O17, revealed that the extent of Ce ion exchange is much greater in case of nanosheets, which may be rationalized by the larger surface area available after exfoliation. XPS measurements show that the ratio of Ce4+/Ce3+ is around 4.4, in agreement with the formation of fluorite structure (CeO2). Thus, these CeO2 nanoparticle/nanosheet composites may be useful for catalytic processes.

  19. Raman spectroscopic studies on CeVO4 at high pressures

    International Nuclear Information System (INIS)

    Rao, Rekha; Garg, Alka B.; Wani, B.N.

    2011-01-01

    Raman scattering investigations of CeVO 4 at high pressures is reported. Polycrystalline CeVO 4 was prepared by solid state reaction of CeO 2 and V 2 O 5 . High pressure Raman spectroscopic measurements were carried out as per experimental details given

  20. SP@CE - An SP-based programming model for consumer electronics streaming applications

    NARCIS (Netherlands)

    Varbanescu, Ana Lucia; Nijhuis, Maik; Escribano, Arturo González; Sips, Henk; Bos, Herbert; Bal, Henri

    2007-01-01

    Efficient programming of multimedia streaming applications for Consumer Electronics (CE) devices is not trivial. As a solution for this problem, we present SP@CE, a novel programming model designed to balance the specific requirements of CE streaming applications with the simplicity and efficiency

  1. Comment on “Synthesis of ceria (CeO_2 and CeO_2_−_x) nanoparticles via decarbonation and Ce(III) oxidation of synthetic bastnaesite (CeCO_3F)” by Montes-Hernandez et al

    International Nuclear Information System (INIS)

    Gysi, Alexander P.; Williams-Jones, Anthony E.

    2016-01-01

    Montes-Hernandez et al. [5] recently reported results of a study of the decarbonation of fine-grained synthetic bastnäsite-(Ce) precipitates involving the oxidation of Ce(III) to Ce(IV) and the formation of ceria (CeO_2 and CeO_2_-_x with oxygen vacancies) nano-particles. The purpose of their study was to show that oxidation of Ce(III) to Ce(IV) occurs spontaneously during heating of bastnäsite-(Ce) in air, a vacuum, N_2 or Ar gas. However, their interpretation of the formation of CeO_2 is not supported by the findings of Gysi and Williams-Jones [3], who showed that natural bastnäsite-(Ce) decomposes to form rare earth element (REE) oxyfluorides (REEOF). The latter was documented using differential scanning calorimetric (DSC) and thermogravimetric (TGA) experiments under a deoxygenated N_2 atmosphere. In their experiments, Gysi and Williams-Jones [3] found no evidence for the oxidation of Ce(III) to Ce(IV). This raises the question of whether the experiments of Montes-Hernandez et al. [5] in a N_2 atmosphere (and by extension in an Ar atmosphere) were compromised because of contamination by O_2 and that, as a result, they reached the erroneous conclusion that Ce(III) oxidizes spontaneously to Ce(IV) during heating of bastnäsite-(Ce) under these conditions. In order to explain the disagreement between their findings and those of Gysi and Williams-Jones [3], Montes-Hernandez et al. [5], proposed that the X-ray diffraction data of the former study were incorrectly interpreted. Here, we provide further evidence that the natural bastnäsite-(Ce) employed in the study by Gysi and Williams-Jones [3] decomposed to form REE oxyfluorides (i.e., CeOF, LaOF, PrOF and NdOF) and not CeO_2, and supply explanations for why Montes-Hernandez et al. [5] erroneously concluded that CeO_2 is produced during decomposition of this mineral under N_2 and Ar atmospheres. In so doing, we hope to provide new insights into the decomposition of bastnäsite-(Ce) that will help guide future

  2. Comment on “Synthesis of ceria (CeO{sub 2} and CeO{sub 2−x}) nanoparticles via decarbonation and Ce(III) oxidation of synthetic bastnaesite (CeCO{sub 3}F)” by Montes-Hernandez et al

    Energy Technology Data Exchange (ETDEWEB)

    Gysi, Alexander P., E-mail: agysi@mines.edu [Department of Geology and Geological Engineering, Colorado School of Mines, 1516 Illinois Street, Golden, CO, 80401 (United States); Williams-Jones, Anthony E. [Department of Earth and Planetary Sciences, McGill University, 3450 University Street, Montreal, QC, Canada, H3A 2A7 (Canada)

    2016-11-01

    Montes-Hernandez et al. [5] recently reported results of a study of the decarbonation of fine-grained synthetic bastnäsite-(Ce) precipitates involving the oxidation of Ce(III) to Ce(IV) and the formation of ceria (CeO{sub 2} and CeO{sub 2-x} with oxygen vacancies) nano-particles. The purpose of their study was to show that oxidation of Ce(III) to Ce(IV) occurs spontaneously during heating of bastnäsite-(Ce) in air, a vacuum, N{sub 2} or Ar gas. However, their interpretation of the formation of CeO{sub 2} is not supported by the findings of Gysi and Williams-Jones [3], who showed that natural bastnäsite-(Ce) decomposes to form rare earth element (REE) oxyfluorides (REEOF). The latter was documented using differential scanning calorimetric (DSC) and thermogravimetric (TGA) experiments under a deoxygenated N{sub 2} atmosphere. In their experiments, Gysi and Williams-Jones [3] found no evidence for the oxidation of Ce(III) to Ce(IV). This raises the question of whether the experiments of Montes-Hernandez et al. [5] in a N{sub 2} atmosphere (and by extension in an Ar atmosphere) were compromised because of contamination by O{sub 2} and that, as a result, they reached the erroneous conclusion that Ce(III) oxidizes spontaneously to Ce(IV) during heating of bastnäsite-(Ce) under these conditions. In order to explain the disagreement between their findings and those of Gysi and Williams-Jones [3], Montes-Hernandez et al. [5], proposed that the X-ray diffraction data of the former study were incorrectly interpreted. Here, we provide further evidence that the natural bastnäsite-(Ce) employed in the study by Gysi and Williams-Jones [3] decomposed to form REE oxyfluorides (i.e., CeOF, LaOF, PrOF and NdOF) and not CeO{sub 2}, and supply explanations for why Montes-Hernandez et al. [5] erroneously concluded that CeO{sub 2} is produced during decomposition of this mineral under N{sub 2} and Ar atmospheres. In so doing, we hope to provide new insights into the decomposition of

  3. Gamma-ray relative energy response of Ce: YAG crystal

    International Nuclear Information System (INIS)

    Zhang Jianhua; Zhang Chuanfei; Hu Mengchun; Peng Taiping; Wang Zhentong; Tang Dengpan; Zhao Guangjun

    2010-01-01

    Gamma-ray relative energy response of Ce: YAG crystal, which is important for pulsed γ-ray measurement, was studied in this work.The Ce: YAG crystal, which was developed at Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, was aligned point by point with γ-rays scattered from an industrial 60 Co line source. The γ-ray relative energy response was calculated using the mass attenuation coefficient. The results show that the numerical calculation method of γ-ray relative energy response is reliable, and the experimental method with multi-energy point γ-ray by Compton scattering is also feasible, that can be used for checking up correctness of the numerical calculation results. (authors)

  4. Identification and Quality Assessment of Chrysanthemum Buds by CE Fingerprinting

    Directory of Open Access Journals (Sweden)

    Xiaoping Xing

    2015-01-01

    Full Text Available A simple and efficient fingerprinting method for chrysanthemum buds was developed with the aim of establishing a quality control protocol based on biochemical makeup. Chrysanthemum bud samples were successively extracted by water and alcohol. The fingerprints of the chrysanthemum buds samples were obtained using capillary electrophoresis and electrochemical detection (CE-ED employing copper and carbon working electrodes to capture all of the chemical information. 10 batches of chrysanthemum buds were collected from different regions and various factories to establish the baseline fingerprint. The experimental data of 10 batches electropherogram buds by CE were analyzed by correlation coefficient and the included angle cosine methods. A standard chrysanthemum bud fingerprint including 24 common peaks was established, 12 from each electrode, which was successfully applied to identify and distinguish between chrysanthemum buds from 2 other chrysanthemum species. These results demonstrate that fingerprint analysis can be used as an important criterion for chrysanthemum buds quality control.

  5. Recent approaches for enhancing sensitivity in enantioseparations by CE.

    Science.gov (United States)

    Sánchez-Hernández, Laura; García-Ruiz, Carmen; Luisa Marina, María; Luis Crego, Antonio

    2010-01-01

    This article reviews the latest methodological and instrumental improvements for enhancing sensitivity in chiral analysis by CE. The review covers literature from March 2007 until May 2009, that is, the works published after the appearance of the latest review article on the same topic by Sánchez-Hernández et al. [Electrophoresis 2008, 29, 237-251]. Off-line and on-line sample treatment techniques, on-line sample preconcentration strategies based on electrophoretic and chromatographic principles, and alternative detection systems to the widely employed UV/Vis detection in CE are the most relevant approaches discussed for improving sensitivity. Microchip technologies are also included since they can open up great possibilities to achieve sensitive and fast enantiomeric separations.

  6. 101Ru NQR study in superconducting CeRu2

    International Nuclear Information System (INIS)

    Matsuda, Kazuyuki; Kohori, Yoh; Kohara, Takao

    1995-01-01

    We present measurements of the NQR spectrum and the nuclear spin lattice relaxation rate, 1/T 1 , of 101 Ru in superconducting CeRu 2 from 1.9 K to 10 K. From the NQR spectrum, the electric quadrupole interaction parameters were determined to be ν Q =13.2 MHz and η=0.1/T 1 varies in proportion to temperature in the normal state, and has the Hebel-Slichter coherence peak just below the superconducting transition temperature, T C , of 6.2 K, and decreases exponentially at low temperatures with the energy gap of 2Δ=4.0k B T C . 101 Ru NQR study indicates that CeRu 2 is an s-wave and strong-coupling superconductor. (author)

  7. TRX and UO2 criticality benchmarks with SAM-CE

    International Nuclear Information System (INIS)

    Beer, M.; Troubetzkoy, E.S.; Lichtenstein, H.; Rose, P.F.

    1980-01-01

    A set of thermal reactor benchmark calculations with SAM-CE which have been conducted at both MAGI and at BNL are described. Their purpose was both validation of the SAM-CE reactor eigenvalue capability developed by MAGI and a substantial contribution to the data testing of both ENDF/B-IV and ENDF/B-V libraries. This experience also resulted in increased calculational efficiency of the code and an example is given. The benchmark analysis included the TRX-1 infinite cell using both ENDF/B-IV and ENDF/B-V cross section sets and calculations using ENDF/B-IV of the TRX-1 full core and TRX-2 cell. BAPL-UO2-1 calculations were conducted for the cell using both ENDF/B-IV and ENDF/B-V and for the full core with ENDF/B-V

  8. Size effect on magnetic ordering in Ce3Al11

    International Nuclear Information System (INIS)

    Wang, C.R.; Chen, Y.Y.; Neeleshwar, S.; Ou, M.N.; Ho, J.C.

    2003-01-01

    To study the size dependence of magnetic ordering, magnetic measurements have been made between 1.8 and 300 K on Ce 3 Al 11 particles having an average particle size of 1400 A. The nanoparticles were single phase as confirmed by X-ray diffraction. At low temperatures a ferromagnetic transition occurs at T C =6.2 K, which is the same as that for the bulk material. On the other hand, the antiferromagnetic transition at T N =3.2 K for the bulk material is not visible down to 1.8 K. Meanwhile, the slightly smaller Curie constant of nanoparticles as compared to that of the bulk indicates a certain degree of demagnetization of Ce ions when the particle size is sufficiently reduced

  9. The high-pressure phase of CePtAl

    International Nuclear Information System (INIS)

    Heymann, Gunter; Heying, Birgit; Rodewald, Ute C.; Janka, Oliver; Univ. Oldenburg

    2017-01-01

    The intermetallic aluminum compound HP-CePtAl was synthesized by arc melting of the elements with subsequent high-pressure/high-temperature treatment at 1620 K and 10.5 GPa in a multianvil press. The compound crystallizes in the hexagonal MgZn_2-type structure (P6_3/mmc) with lattice parameters of a=552.7(1) and c=898.8(2) pm refined from powder X-ray diffraction data. With the help of single crystal investigations (wR=0.0527, 187 F"2 values, 13 variables), the proposed structure type was confirmed and the mixed Pt/Al site occupations could be refined. Magnetic susceptibility measurements showed a disappearance of the complex magnetic ordering phenomena, which are observed in NP-CePtAl.

  10. The high-pressure phase of CePtAl

    Energy Technology Data Exchange (ETDEWEB)

    Heymann, Gunter [Univ. Innsbruck (Austria). Inst. fuer Allgemeine, Anorganische und Theoretische Chemie; Heying, Birgit; Rodewald, Ute C. [Univ. Muenster (Germany). Inst. fuer Anorganische und Analytische Chemie; Janka, Oliver [Univ. Muenster (Germany). Inst. fuer Anorganische und Analytische Chemie; Univ. Oldenburg (Germany). Inst. fuer Chemie

    2017-03-01

    The intermetallic aluminum compound HP-CePtAl was synthesized by arc melting of the elements with subsequent high-pressure/high-temperature treatment at 1620 K and 10.5 GPa in a multianvil press. The compound crystallizes in the hexagonal MgZn{sub 2}-type structure (P6{sub 3}/mmc) with lattice parameters of a=552.7(1) and c=898.8(2) pm refined from powder X-ray diffraction data. With the help of single crystal investigations (wR=0.0527, 187 F{sup 2} values, 13 variables), the proposed structure type was confirmed and the mixed Pt/Al site occupations could be refined. Magnetic susceptibility measurements showed a disappearance of the complex magnetic ordering phenomena, which are observed in NP-CePtAl.

  11. 10 GHz 2ωce heavy ion source CAPRICE

    International Nuclear Information System (INIS)

    Jacquot, B.; Briand, P.; Bourg, F.; Geller, R.

    1988-01-01

    By using a new 0.8 T sextupole, the second step of metamorphosis of the ECR magnetic structure of the CAPRICE source is achieved. The 2ω ce surface is now extended everywhere in the second stage except the extraction part. Thus, a strong flux of deconfined plasma is available at the extraction area and therefore high currents of high charge state ions are extracted. Optimum rf power is increased by a factor of 3 with respect to the single ω ce profile and currents of high charge state ions are increased by a factor of 10. The optimum performance for all gases and all solid elements is shown. The third step of the metamorphosis is planned for next year to achieve and work with two complete ECR surfaces. Future developments are also expected. (orig./HSI)

  12. Ni-CeO2 Cermets Synthesis by Solid State Sintering of Ni/CeO2 Multilayer

    Directory of Open Access Journals (Sweden)

    Aleksandras ILJINAS

    2013-12-01

    Full Text Available Nickel and gadolinium doped cerium oxide (GDC cermet is intensively investigated for an application as an anode material for solid oxide fuel cells based on various electrolytes. The purpose of the present investigation is to analyze morphology, microstructure, and optical properties of deposited and annealed for one hour in the temperatures from 500 ºC to 900 ºC Ni/CeO2 multilayer thin films deposited by sputtering. The crystallographic structure of thin films was investigated by X-ray diffraction. The morphology of the film cross-section was investigated with scanning electron microscope. The elemental analysis of samples was investigated by energy-dispersive X-ray spectroscopy. The fitting of the optical reflectance data was made using Abeles matrix method that is used for the design of interference coatings. The film cross-section of the post-annealed samples consisted of four layers. The first CeO2 layer (on Si had the same fine columnar structure with no features of Ni intermixing. The part of Ni (middle-layer after annealing was converted to NiO with grain size exceeding 100 nm. The CeO2 layer deposited on Ni was divided into two layers. Lower layer had small grains not exceeding 25 nm and consisting of NiO and CeO2 mixture. Upper layer consisted of CeO2 columns with approximate thickness of 50 nm. Ni sample annealed at 600 ºC was fully oxidized. The NiO thickness and refraction index were almost steady after annealing in various temperatures. The approximation of experimental reflectance data was successful only for the samples with one transparent homogeneous layer. The reflectance of the Ni/CeO2 samples annealed at intermediate temperatures could not be fitted using one-layer or three-layer model. That may show that a simplified model could not be implemented.  The real system has complicated distribution of refraction index. DOI: http://dx.doi.org/10.5755/j01.ms.19.4.3073

  13. Ce-didymium-Fe-B sintered permanent magnets

    International Nuclear Information System (INIS)

    Homma, M.; Okada, M.; Sugimoto, S.

    1985-01-01

    Present works report the development of the low cost R-Fe-B permanent magnets. The best magnetic properties obtained in this studies are Br=13.5 kG, iHc=10.2 kOe and (BH)max=40 MGOe with an Fe-33.5wt%(5Ce-Didymium)-1wt% B alloy. Topics considered in this paper include cerium alloys, boron alloys, fabrication, capitalized cost, iron alloys, permanent magnets, and magnetic properties

  14. Optical spectroscopy of the Ce-doped multicomponent garnets

    International Nuclear Information System (INIS)

    Canimoglu, A.; Karabulut, Y.; Ayvacikli, M.; Muresan, L.E.; Perhaita, I.; Barbu-Tudoran, L.; Garcia Guinea, J.; Karali, T.; Can, N.

    2016-01-01

    Here, we report our results referring to the preparation of Ce doped Y 2.22 MgGa 2 Al 2 SiO 12 , Y 1.93 MgAl 4 SiO 12 and Y 2.22 Gd 0.75 Ga 2 Al 3 O 12 using solid state reaction at high temperature. Several complementary methods (i.e. powder x-ray diffraction (XRPD), energy dispersive analysis of X-rays (EDX), scanning electron microscopy (SEM) and Fourier transforms infrared spectroscopy (FTIR)) were studied to examine the effects of the synthesis procedure on the morphology and structure. XRD analyses revealed that all compounds include yttrium aluminate phase with garnet structure. Cathodoluminescence (CL), radioluminescence (RL) and photoluminescence (PL) measurements were carried out for clarification of relationship between host lattice defects and the spectral luminescence emissions. Luminescence emission of phosphors is peaked at 530 nm assigned to 5d-4f transitions of the dopant Ce 3+ ions with a broad emission band in 400–700 nm range. Under electron irradiation, the emission spectrum of Ce doped (YGd) 3 Ga 2 Al 3 O 12 is well defined and has a characteristic fairly narrow and sharp emission band peaking at 312 nm and 624 nm corresponding to transition of 6 P 7/2 → 8 S 7/2 and 6 G J → 6 P J (Gd 3+ ), respectively. We suggest some of phosphors might be excellent phototherapy phosphor materials under electron excitation. - Highlights: • Ce-doped Multicomponent Garnets were prepared solid state reaction method. • The shape and size of phosphor particles were examined. • The narrow band UV B emission due to Gd 3+ ions were observed.

  15. Qu'est-ce que l'Univers ?

    CERN Document Server

    2001-01-01

    Les plus grans spécialistes français sont réunis dans ce quatrième volume. Ils éclairent les grandes questions que pose la cosmologie, le Système solaire, les étoiles et les galaxies, la Terre, les océans et le climat, la matière et son organisation, l'évolution des mathématiques, la complexité, les transformations chimiques.

  16. Proposal for product development model focused on ce certification methodology

    Directory of Open Access Journals (Sweden)

    Nathalia Marcia Goulart Pinheiro

    2015-09-01

    Full Text Available This paper presents a critical analysis comparing 21 product development models in order to identify whether these structures meet the demands Product Certification of the European Community (CE. Furthermore, it presents a product development model, comprising the steps in the models analyzed, including improvements in activities for referred product certification. The proposed improvements are justified by the growing quest for the internationalization of products and processes within companies.

  17. CeDAMar global database of abyssal biological sampling

    OpenAIRE

    Stuart, Carol T.; Arbizu, Pedro Martinez; Smith, Craig R.; Molodtsova, Tina; Brandt, Angelika; Etter, Ron J.; Escobar-briones, Elva; Fabri, Marie-claire; Rex, Michael A.

    2008-01-01

    The Census of the Diversity of Abyssal Marine Life (CeDAMar), a division of the Census of Marine Life, has compiled the first comprehensive global database of biological samples taken in the abyssal plains of the world ocean. It is an essential resource for planning future exploration of the abyss, for synthesizing patterns of biogeography and biodiversity, and for environmentally safe exploitation of natural resources. The database is described in this article, and made available to investig...

  18. Systematics of triaxial deformation in Xe, Ba, and Ce nuclei

    International Nuclear Information System (INIS)

    Yan, J.; Vogel, O.; von Brentano, P.; Gelberg, A.

    1993-01-01

    The (β,γ) deformation parameters of even-even Xe, Ba, and Ce nuclei have been calculated by using the triaxial rotor model. Deformation parameters calculated, on one hand, from decay properties and, on the other hand, from energies are in good agreement. The smooth dependence of the deformation parameters on Z and N is discussed. The results are compared with those extracted from properties of odd-A nuclei

  19. Reaction /sup 140/Ce (e, e'p), (2)

    Energy Technology Data Exchange (ETDEWEB)

    Saito, T; Shoda, K [Tohoku Univ., Sendai (Japan). Lab. of Nuclear Science

    1975-06-01

    An experiment was carried out to study the character of the resonance observed at 24.4 MeV in the /sup 140/Ce (..gamma.., p) /sup 139/La reaction. The (..gamma.., p/sub 0/ + p/sub 1/) cross section was measured at the angles of 54.7/sup 0/ and 125.3/sup 0/, at which the angle-dependent term of E1 becomes zero, for the energy range between 19 and 26 MeV. Existence of a peak due to the E2 resonance around 24.4 MeV was examined. The energy of incident electrons from a linear accelerator was changed between 20 and 26.7 MeV. The target was a Ce foil of 7.3 mg/cm/sup 2/ thick. The proton spectra due to the /sup 140/Ce (e, e' p) /sup 139/La reaction were measured with a broad range magnetic spectrometer. In the determined spectra of /sup 140/Ce (..gamma.., p/sub 0/+p/sub 1/) /sup 139/La, any remarkable peak, except one at 20.5 MeV, was not seen. From the observed spectra, the total cross section and the asymmetry factor due to interference were obtained as functions of energy. The values of the asymmetry factor were almost flat in the energy range between 19 and 26 MeV. The resonance at 24.4 MeV in the total cross section may be due to the E1 resonance, and is not due to the E2.

  20. Scintillation properties of the Ce-doped multicomponent garnetepitaxial films

    Czech Academy of Sciences Publication Activity Database

    Průša, Petr; Kučera, M.; Mareš, Jiří A.; Hanuš, M.; Beitlerová, Alena; Onderišinová, Z.; Nikl, Martin

    2013-01-01

    Roč. 35, č. 12 (2013), s. 2444-2448 ISSN 0925-3467 R&D Projects: GA ČR GAP204/12/0805 Institutional support: RVO:68378271 Keywords : scintillator * liquid phase epitaxy method * photoelectron yield * garnet * Ce 3+ Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 2.075, year: 2013 http://dx.doi.org/10.1016/j.optmat.2013.06.051

  1. Nouvelle espèce des Syntomides (Lepidoptera Heterocera)

    NARCIS (Netherlands)

    Snellen, P.C.T.

    1886-01-01

    Quatre mâles frais et bien conservés de 58—64 millim. d’envergure. Cette nouvelle espèce, gigantesque pour une Syntomide, appartient au genre Automolis, tel qu’il a été défini par Herrich-Schäffer, dans son ouvrage »Sammlung aussereuropäischer Schmetterlinge” (p. 21); le nom est emprunté au bien

  2. Determination of the differences in oxidation potentials for the Pr3+/Pr2+ and Ce3+/Ce2+ pairs in halide melts

    International Nuclear Information System (INIS)

    Mikheev, N.B.; Auerman, L.N.; Rumer, I.A.; D'yachkova, R.A.

    1983-01-01

    Cocrystallization has been used with the (PrOCl)/sub s. ph/ - (PrCl 2 , PrCl 3 , SrCl 2 ) melt system to examine the dependence of the cerium(III) cocrystallization coefficient on the X/sub Pr 2+ /X/sub Pr 3+ / ratio in the melt. Measurement has been made in this way of the difference in oxidation potentials for the pairs Pr 3+ /Pr 2+ and Ce 3+ /Ce 2+ : ΔE/sub Pr 3+ /Pr 2+0 -E/sub Ce 3+ /Ce 2+ / 0 , which is 0.08 +/- 0.04 V for chloride

  3. Physical, biochemical and genetic characterization of enterocin CE5-1 produced by Enterococcus faecium CE5-1 isolated from Thai indigenous chicken intestinal tract

    OpenAIRE

    Kraiyot Saelim; Sireewan Kaewsuwan; Akio Tani; Suppasil Maneerat

    2015-01-01

    Enterocin CE5-1 produced by Enterococcus faecium CE5-1 isolated from the chicken gastrointestinal tract was active in the wide range of pH 2-10 and temperature 30-100°C and sensitive to proteolytic enzymes and -amylase. It remained active after storage at -20°C for 2 months. Moreover, enterocin CE5-1 showed antibacterial activity against lactobacilli, bacilli, listeria, staphylococci and enterococci, especially antibiotic-resistant enterococci. In vitro study of enterocin CE5-1 decr...

  4. XAFS Analysis of Local Structure around Ce in Ca3Sc2Si3O12:Ce Phosphor for White LEDs

    International Nuclear Information System (INIS)

    Akai, Toshio; Shigeiwa, Motoyuki; Okamoto, Kaoru; Shimomura, Yasuo; Kijima, Naoto; Honma, Tetsuo

    2007-01-01

    We have studied the local structure around Ce atom in Ca3Sc2Si3O12 host crystal, which has been developed as a new green phosphor for white light emitting diodes (LEDs). As the local structure and chemical environment of the dopant atom are very important to improve the performance of the phosphor, we have used XAFS to get chemical and structural information around the Ce dopant. The XANES spectrum of the Ce LIII-edge reveals that the Ce atom is trivalent in Ca3Sc2Si3O12. There are two kinds of possible Ce substitution sites, Ca site and Sc site, in garnet type Ca3Sc2Si3O12 crystal structure. The Ce atom is found to be at the Ca site in the host crystal by the comparison of the Fourier transform of Ce K-edge EXAFS spectrum with those of Ca and Sc K-edge EXAFS spectra. The theoretical analysis with FEFF also clarified the Ce substitution at the Ca site. Furthermore, the result of the analysis indicates the structural disorder around Ca and Si atoms at 3.75 A. It is possible that there are some defects around the Ca and Si atoms at 3.75 A to compensate the excess positive charge by introduced Ce3+ at the Ca2+ site

  5. Redox potentials and kinetics of the Ce 3+/Ce 4+ redox reaction and solubility of cerium sulfates in sulfuric acid solutions

    Science.gov (United States)

    Paulenova, A.; Creager, S. E.; Navratil, J. D.; Wei, Y.

    Experimental work was performed with the aim of evaluating the Ce 4+/Ce 3+ redox couple in sulfuric acid electrolyte for use in redox flow battery (RFB) technology. The solubility of cerium sulfates in 0.1-4.0 M sulfuric acid at 20-60 °C was studied. A synergistic effect of both sulfuric acid concentration and temperature on the solubility of cerous sulfate was observed. The solubility of cerous sulfate significantly decreased with rising concentration of sulfuric acid and rising temperature, while the solubility of ceric sulfate goes through a significant maximum at 40 °C. Redox potentials and the kinetics of the cerous/ceric redox reaction were also studied under the same temperature-concentration conditions. The redox potentials were measured using the combined redox electrode (Pt-Ag/AgCl) in equimolar Ce 4+/Ce 3+ solutions (i.e.[Ce 3+]=[Ce 4+]) in sulfuric acid electrolyte. The Ce 3+/Ce 4+ redox potentials significantly decrease (i.e. shift to more negative values) with rising sulfuric acid concentration; a small maximum is observed at 40 °C. Cyclic voltammetric experiments confirmed slow electrochemical kinetics of the Ce 3+/Ce 4+ redox reaction on carbon glassy electrodes (CGEs) in sulfuric acid solutions. The observed dependencies of solubilities, the redox potentials and the kinetics of Ce 3+/Ce 4+ redox reaction on sulfuric acid concentration are thought to be the result of inequivalent complexation of the two redox species by sulfate anions: the ceric ion is much more strongly bound to sulfate than is the cerous ion. The best temperature-concentration conditions for the RFB electrolytes appear to be 40 °C and 1 M sulfuric acid, where the relatively good solubility of both cerium species, the maximum of redox potentials, and the more or less satisfying stability of CGE s were found. Even so, the relatively low solubility of cerium salts in sulfuric acid media and slow redox kinetics of the Ce 3+/Ce 4+ redox reaction at carbon indicate that the Ce 3+/Ce

  6. Physical, biochemical and genetic characterization of enterocin CE5-1 produced by Enterococcus faecium CE5-1 isolated from Thai indigenous chicken intestinal tract

    Directory of Open Access Journals (Sweden)

    Kraiyot Saelim

    2015-06-01

    Full Text Available Enterocin CE5-1 produced by Enterococcus faecium CE5-1 isolated from the chicken gastrointestinal tract was active in the wide range of pH 2-10 and temperature 30-100°C and sensitive to proteolytic enzymes and -amylase. It remained active after storage at -20°C for 2 months. Moreover, enterocin CE5-1 showed antibacterial activity against lactobacilli, bacilli, listeria, staphylococci and enterococci, especially antibiotic-resistant enterococci. In vitro study of enterocin CE5-1 decreased the population of Ent. faecalis VanB from 6.03 to 4.03 log CFU/ml. The lethal mode of action of enterocin CE5-1 appeared to be pore and filament formation in the cell wall. PCR sequencing analysis revealed the presence of two open reading frames (ORFs, containing enterocin CE5-1 (entCE5-1 and enterocin immunity (entI gene. Therefore, enterocin CE5-1 from Ent. faecium CE5-1 could possibly be used as an antimicrobial agent to control foodborne pathogen, spoilage bacteria and antibiotic-resistant enterococci in foods, feeds and the environments.

  7. Radon gamma-ray spectrometry with YAP:Ce scintillator

    CERN Document Server

    Plastino, W; De Notaristefani, F

    2002-01-01

    The detection properties of a YAP:Ce scintillator (YAlO sub 3 :Ce crystal) optically coupled to a Hamamatsu H5784 photomultiplier with standard bialkali photocathode have been analyzed. In particular, the application to radon and radon-daughters gamma-ray spectrometry was investigated. The crystal response has been studied under severe extreme conditions to simulate environments of geophysical interest, particularly those found in geothermal and volcanic areas. Tests in water up to a temperature of 100 deg.C and in acids solutions such as HCl (37%), H sub 2 SO sub 4 (48%) and HNO sub 3 (65%) have been performed. The measurements with standard radon sources provided by the National Institute for Metrology of Ionizing Radiations (ENEA) have emphasized the non-hygroscopic properties of the scintillator and a small dependence of the light yield on temperature and HNO sub 3. The data collected in this first step of our research have pointed out that the YAP:Ce scintillator can allow high response stability for rad...

  8. F-centre luminescence in nanocrystalline CeO2

    International Nuclear Information System (INIS)

    Aškrabić, S; Dohčević-Mitrović, Z D; Araújo, V D; Ionita, G; De Lima, M M Jr; Cantarero, A

    2013-01-01

    Nanocrystalline CeO 2 powders were synthesized by two cost-effective methods: the self-propagating room temperature (SPRT) method and the precipitation method. Differently prepared samples exhibited different temperature-dependent photoluminescence (PL) in the ultraviolet and visible regions. The PL signals originated from different kinds of oxygen-deficient defect centres with or without trapped electrons (F 0 , F + or F ++ centres). The temperature-dependent PL spectra were measured using different excitation lines, below (457, 488 and 514 nm) or comparable (325 nm) to the ceria optical band gap energy, in order to investigate the positions of intragap localized defect states. Evidence for the presence of F + centres was supported by the signals observed in electron paramagnetic resonance (EPR) measurements. Based on PL and EPR measurements it was shown that F + centres dominate in the CeO 2 sample synthesized by the SPRT method, whereas F 0 centres are the major defects in the CeO 2 sample synthesized by the precipitation method. The luminescence from F ++ states, as shallow trap states, was registered in both samples. Energy level positions of these defect states in the ceria band gap were proposed. (paper)

  9. F-centre luminescence in nanocrystalline CeO2

    Science.gov (United States)

    Aškrabić, S.; Dohčević-Mitrović, Z. D.; Araújo, V. D.; Ionita, G.; de Lima, M. M., Jr.; Cantarero, A.

    2013-12-01

    Nanocrystalline CeO2 powders were synthesized by two cost-effective methods: the self-propagating room temperature (SPRT) method and the precipitation method. Differently prepared samples exhibited different temperature-dependent photoluminescence (PL) in the ultraviolet and visible regions. The PL signals originated from different kinds of oxygen-deficient defect centres with or without trapped electrons (F0, F+ or F++ centres). The temperature-dependent PL spectra were measured using different excitation lines, below (457, 488 and 514 nm) or comparable (325 nm) to the ceria optical band gap energy, in order to investigate the positions of intragap localized defect states. Evidence for the presence of F+ centres was supported by the signals observed in electron paramagnetic resonance (EPR) measurements. Based on PL and EPR measurements it was shown that F+ centres dominate in the CeO2 sample synthesized by the SPRT method, whereas F0 centres are the major defects in the CeO2 sample synthesized by the precipitation method. The luminescence from F++ states, as shallow trap states, was registered in both samples. Energy level positions of these defect states in the ceria band gap were proposed.

  10. Magnetoresistance in CePtSn under high hydrostatic pressures

    International Nuclear Information System (INIS)

    Misek, M.; Prokleska, J.; Javorsky, P.; Sechovsky, V.

    2009-01-01

    We report the evolution of magnetic-history dependent antiferromagnetic phases in CePtSn. We concentrate on the magnetoresistance in magnetic fields up to 14 T applied along the crystallographic b-axis, measured on a CePtSn single crystal subjected to hydrostatic pressure (p ≤ 2.2 GPa) generated in a double-layered CuBe/NiCrAl piston cylinder cell. We observe a gradual increase of the critical field B c LF of the low field (LF) transition up to ∼1.2 GPa where only one transition is observed at ∼11.5 T. For pressures above 1.2 GPa we observe two transitions again and B c LF decreases with further increasing pressure to reach B c LF ∼7.5T at 2.5 GPa. The position of the high field (HF) transition remains almost unaffected by applied pressure. A scenario considering the spin-slip AF structure in CePtSn is briefly discussed.

  11. NMR study of CeTe at low temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Hinderer, J. [Laboratorium fuer Festkoerperphysik, ETH Zuerich, CH-8093 Zurich (Switzerland)]. E-mail: hinderer@phys.ethz.ch; Weyeneth, S.M. [Laboratorium fuer Festkoerperphysik, ETH Zuerich, CH-8093 Zurich (Switzerland); Weller, M. [Laboratorium fuer Festkoerperphysik, ETH Zuerich, CH-8093 Zurich (Switzerland); Gavilano, J.L. [Laboratorium fuer Festkoerperphysik, ETH Zuerich, CH-8093 Zurich (Switzerland); Felder, E. [Laboratorium fuer Festkoerperphysik, ETH Zuerich, CH-8093 Zurich (Switzerland); Hulliger, F. [Laboratorium fuer Festkoerperphysik, ETH Zuerich, CH-8093 Zurich (Switzerland); Ott, H.R. [Laboratorium fuer Festkoerperphysik, ETH Zuerich, CH-8093 Zurich (Switzerland)

    2006-05-01

    We present {sup 125}Te NMR measurements on CeTe powder at temperatures between 1 and 150K and in magnetic fields between 5 and 8T. CeTe is a rocksalt-type intermetallic compound. It orders antiferromagnetically at T{sub N}{approx}2.2K with a much reduced ordered moment [H.R. Ott, J.K. Kjems, F. Hulliger, Phys. Rev. Lett. 42 20 (1979) 1378]. From our low-temperature NMR spectra we infer the presence of at least three inequivalent Te sites at low temperatures. Considering the crystal structure this result is completely unexpected. The linewidths and the Knight shifts of the individual lines are significantly different and increase substantially with decreasing temperature. They follow the temperature dependence of the magnetic susceptibility above 20K. Above T{sub N}, hyperfine fields of 1.6, 0.8 and 0.0T at the three Te sites per Bohr magneton of Ce moment are deduced from Knight shift vs. magnetic susceptibility data. These values are typical for transferred hyperfine fields via conduction electrons.

  12. Air, aqueous and thermal stabilities of Ce3+ ions in cerium oxide nanoparticle layers with substrates

    KAUST Repository

    Naganuma, Tamaki

    2014-01-01

    Abundant oxygen vacancies coexisting with Ce3+ ions in fluorite cerium oxide nanoparticles (CNPs) have the potential to enhance catalytic ability, but the ratio of unstable Ce3+ ions in CNPs is typically low. Our recent work, however, demonstrated that the abundant Ce3+ ions created in cerium oxide nanoparticle layers (CNPLs) by Ar ion irradiation were stable in air at room temperature. Ce valence states in CNPs correlate with the catalytic ability that involves redox reactions between Ce3+ and Ce4+ ions in given application environments (e.g. high temperature in carbon monoxide gas conversion and immersion conditions in biomedical applications). To better understand the mechanism by which Ce3+ ions achieve stability in CNPLs, we examined (i) extra-long air-stability, (ii) thermal stability up to 500 °C, and (iii) aqueous stability of Ce 3+ ions in water, buffer solution and cell culture medium. It is noteworthy that air-stability of Ce3+ ions in CNPLs persisted for more than 1 year. Thermal stability results showed that oxidation of Ce 3+ to Ce4+ occurred at 350 °C in air. Highly concentrated Ce3+ ions in ultra-thin CNPLs slowly oxidized in water within 1 day, but stability was improved in the cell culture medium. Ce 3+ stability of CNPLs immersed in the medium was associated with phosphorus adsorption on the Ce3+ sites. This study also illuminates the potential interaction mechanisms of stable Ce3+ ions in CNPLs. These findings could be utilized to understand catalytic mechanisms of CNPs with abundant oxygen vacancies in their application environments. © The Royal Society of Chemistry 2014.

  13. Microstructures and luminescent properties of Ce-doped transparent mica glass-ceramics

    International Nuclear Information System (INIS)

    Taruta, Seiichi; Iwasaki, Yoshitomo; Nishikiori, Hiromasa; Yamakami, Tomohiko; Yamaguchi, Tomohiro; Kitajima, Kunio; Okada, Kiyoshi

    2012-01-01

    Highlights: ► Ce-doped transparent glass-ceramics and their parent glasses. ► TEM and STEM images for the microstructures. ► Each mica crystal did not contain Ce uniformly. ► Emission due to Ce 3+ ions in the glass phase and/or Ce 3+ ions in the mica crystals. - Abstract: Transparent mica glass-ceramics were prepared by heating parent glasses that had been doped with 0.5–15 mol% CeO 2 . During the melting and heat treatment, Ce 4+ ions in the specimens were reduced to Ce 3+ ions, and one or both of these ion species were then replaced with Li + ions in the interlayers of the separated mica crystals. However, scanning transmission electron microscope (STEM) and Z-contrast imaging revealed that the mica crystals did not contain the same amount of Ce. On excitation at 254 nm, the parent glasses and glass-ceramics emitted blue light, which originated from the 5d to 4f transition of the Ce 3+ ions. The emission of the glass-ceramic containing a smaller amount of Ce was attributed to the Ce 3+ ions in both the glass phase and the mica crystals, whereas that of the glass-ceramics containing a larger amount of Ce was caused mainly by Ce 3+ ions in the mica crystals. The dependence of the emission band of the parent glasses on the amount of Ce was a unique feature of the Ce-doped transparent mica glass-ceramics and was not observed in previous studies of Eu-doped parent glasses and mica glass-ceramics.

  14. The γ rays sensitivity measurement of CeF3 scintillator detector

    International Nuclear Information System (INIS)

    Hu Mengchun; Zhou Dianzhong; Li Rurong; Wang Zhentong; Yang Hongqiong; Zhang Jianhua; Hu Qingyuan; Peng Taiping

    2003-01-01

    The CeF 3 is an abio-scintillator developed in recent years, which are insensitive to neutron and sensitive to gamma rays and respond quickness. The relationship of CeF 3 scintillation detector gamma rays sensitivity with the change of crystal thickness was measured. The CeF 3 scintillation detector is composed by high liner current photomultiplier tube of CHφT3, CHφT5 and CeF 3 scintillator. The detector gamma rays sensitivity of purple photocell and common photocell with CeF 3 scintillator were measured too

  15. CeBr3 as a room-temperature, high-resolution gamma-ray detector

    International Nuclear Information System (INIS)

    Guss, Paul; Reed, Michael; Yuan Ding; Reed, Alexis; Mukhopadhyay, Sanjoy

    2009-01-01

    Cerium bromide (CeBr 3 ) has become a material of interest in the race for high-resolution gamma-ray spectroscopy at room temperature. This investigation quantified the potential of CeBr 3 as a room-temperature, high-resolution gamma-ray detector. The performance of CeBr 3 crystals was compared to other scintillation crystals of similar dimensions and detection environments. Comparison of self-activity of CeBr 3 to cerium-doped lanthanum tribromide (LaBr 3 :Ce) was performed. Energy resolution and relative intrinsic efficiency were measured and are presented.

  16. Investigation into kinetics of redox interaction in the system Ce(4) β-diketonate-additional ligand

    International Nuclear Information System (INIS)

    Anufrieva, S.I.; Snezhko, N.I.; Pechurova, N.I.; Martynenko, L.N.; Spitsyn, V.I.

    1981-01-01

    The rate of reduction of β-diketonate complexes of Ce(4) to Ce(3) β-diketonates in benzene solution in the presence and in the absence of additional ligands is studied using spectrophotometry. The rate of reduction of Ce(4) β-diketonates increases in the series Ce(TTFA) 4 4 4 4 4 (TTFA - thenoyltrifluoroacetone, DPM- --dipivaloylmethane, DBM - dibenzoylemethane, BA benzoylacetone, AA - acetylaceton). The studied phosphorus-containing additional ligands as to their effect on the rate of Ce (4) reduction can be arranged in the following order: trioctylphosphine oxide>triphenylphosphine oxide>tributyl phosphate [ru

  17. Controlled hydrothermal synthesis of CeO{sub 2} nanospheres and their excellent magnetic properties

    Energy Technology Data Exchange (ETDEWEB)

    Niu, Xiaofei [Suzhou University, Anhui Key Laboratory of Spintronics and Nanomaterials Research, Suzhou, Anhui (China)

    2017-04-15

    Monodisperse spherical CeO{sub 2} nanostructures with irregular and rough surfaces have successfully been synthesized via a facile hydrothermal technology. XRD, SEM, XPS, Raman scattering, and M-H curves were employed to characterize the samples. The results showed that the spherical CeO{sub 2} nanostructures have a cubic fluorite structure and that there are Ce{sup 3+} ions and oxygen vacancies in the surface of the samples. The M-H curve of CeO{sub 2} nanospheres exhibits excellent room-temperature ferromagnetism (RT-FM), which is likely ascribed to the effects of the Ce{sup 3+} ions and oxygen vacancies. (orig.)

  18. LiCaAlF sub 6 :Ce crystal: a new scintillator

    CERN Document Server

    Gektin, A V; Neicheva, S; Gavrilyuk, V; Bensalah, A; Fukuda, T; Shimamura, K

    2002-01-01

    Scintillation properties of LiCaAlF sub 6 :Ce crystal, well known as the effective UV laser material, is reported. Ce sup 3 sup + emission at 286-305 nm with a single exponential decay time of 35 ns provides a scintillation pulse. Radiation damage in pure and Ce-doped crystals is studied. In contrast to the majority of fluoride crystals, cerium is responsible for the ultradeep traps formation revealing thermostimulated luminescence. Overlapping of color center absorption and Ce sup 3 sup + ion emission bands limits the scintillation efficiency of LiCaAlF sub 6 :Ce at high radiation doses.

  19. Non-aqueous CE-MS of cinchona alkaloids - characterizationof a novel CE-ESI-MS interface

    DEFF Research Database (Denmark)

    Hansen, Frederik André; Hansen, Steen Honoré; Petersen, Nickolaj J.

    We have recently in our group at the University of Copenhagen developed a robust and simple sheatless CE-ESI-MS interface (capillary electrophoresis – electrospray ionization-mass spectrometry). In this presentation the interface is characterized and compared with HPLC-MS for studying...... a submicron fracture in the capillary close the ESI tip. The fracture provides a zero dead volume and excellent conducting properties due to the large amount of ions in the electric double layer. Electric current exceeding the upper limit of CE instrumentation of up to 300 µA can easily be obtained....... Furthermore, the increased conductivity of the buffer in the fracture generates field free pumping of the analytes towards the ESI spray tip. In this study the device was used to analyze the four major alkaloids (diastereomeric pairs of quinine/quinidine and cinchonine/cinchonidine) in Cinchona bark samples...

  20. The Environment Analysis in the CE-3 Landing Region

    Science.gov (United States)

    Mu, L.; Liu, J.; Zeng, X.; Gao, X.; Yan, W.; Zou, X.; Li, C.

    2014-12-01

    To understand the environment and select detecting objects for the Yutu Rover, NAOC used the DEM and DOM data obtained by CE-2, geological data released by USGS, and high resolution image captured by CE-3 and LRO-NAC to analyze the topographical characteristic, geologic age, Geomorphological feathers and new dust distribution in two scale levels. The first level is 45km×75km, and another one is 4km×4km. The center of the study region is the CE-3 landing site (19.51°W, 44.12°N). The following is the initial conclusions: (1) CE-3 landed on a relatively flat region in the Mare Imbrium with an elevation of -2615m. The geological age of the landing site belongs to young Eratoshenian. 10km to the north of the landing site is the older Mare Imbrium stratum, and the location of the landing site is just on the intersection area of these two stratums. (2) The landing site lies on the edge of a lunar mountain with a decline tendency from west to east, and the topographic slope and roughness of the landing region is low, which is the typical characteristic of lunar mare. There is a big crater with diameter of 430 meters in the west of the landing site, and lots of stones in different colors on the rim of this crater, shown in the Figure2. (3) By comparing the images captured by LRO-NAC before and after the landing, much lunar dust was blown away by the engine plume during the landing of CE-3. The change scope is about 60m with from east-west and 135m length from south-north. The direction of landing is from south-north, so the length is larger than the width, shown in the figure 3. (4) In the initial stage, the Yutu Rover was suggested to move in south direction and late in north direction, which would get more scientific data and result.

  1. Numerical simulation of the geometrical-optics reduction of CE2 and comparisons to quasilinear dynamics

    Science.gov (United States)

    Parker, Jeffrey B.

    2018-05-01

    Zonal flows have been observed to appear spontaneously from turbulence in a number of physical settings. A complete theory for their behavior is still lacking. Recently, a number of studies have investigated the dynamics of zonal flows using quasilinear (QL) theories and the statistical framework of a second-order cumulant expansion (CE2). A geometrical-optics (GO) reduction of CE2, derived under an assumption of separation of scales between the fluctuations and the zonal flow, is studied here numerically. The reduced model, CE2-GO, has a similar phase-space mathematical structure to the traditional wave-kinetic equation, but that wave-kinetic equation has been shown to fail to preserve enstrophy conservation and to exhibit an ultraviolet catastrophe. CE2-GO, in contrast, preserves nonlinear conservation of both energy and enstrophy. We show here how to retain these conservation properties in a pseudospectral simulation of CE2-GO. We then present nonlinear simulations of CE2-GO and compare with direct simulations of quasilinear (QL) dynamics. We find that CE2-GO retains some similarities to QL. The partitioning of energy that resides in the zonal flow is in good quantitative agreement between CE2-GO and QL. On the other hand, the length scale of the zonal flow does not follow the same qualitative trend in the two models. Overall, these simulations indicate that CE2-GO provides a simpler and more tractable statistical paradigm than CE2, but CE2-GO is missing important physics.

  2. Effect of cerium on the corrosion behaviour of sintered (Nd,Ce)FeB magnet

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Lijing [CAS Key Laboratory of Magnetic Materials and Devices, Zhejiang Province Key Laboratory of Magnetic Materials and Application Technology, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201 (China); Bi, Mengxue [CAS Key Laboratory of Magnetic Materials and Devices, Zhejiang Province Key Laboratory of Magnetic Materials and Application Technology, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201 (China); Nano Science and Technology Institute, University of Science and Technology of China, Hefei 230026 (China); Jiang, Jianjun; Ding, Xuefeng [CAS Key Laboratory of Magnetic Materials and Devices, Zhejiang Province Key Laboratory of Magnetic Materials and Application Technology, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201 (China); Zhu, Minggang; Li, Wei [Functional Materials Research Institute, Central Iron & Steel Research Institute, Beijing 100081 (China); Lv, Zhongshan [Ningbo Shuo Teng new material Co., Ltd., Cixi 315301 (China); Song, Zhenlun, E-mail: songzhenlun@nimte.ac.cn [CAS Key Laboratory of Magnetic Materials and Devices, Zhejiang Province Key Laboratory of Magnetic Materials and Application Technology, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201 (China)

    2017-06-15

    Highlights: • A little Ce could promote the magnets for a better corrosion resistance. • With increased Ce contents, the corrosion resistances of magnets decrease. • As the corrosion developed, the magnetic properties decreased. - Abstract: For the balanced consumption of rare-earth elements, cerium (Ce) was partially used for NdFeB magnets instead of Nd. The corrosion behaviour of the (Nd,Ce)FeB magnet with different Ce contents in 3.5% NaCl solution was investigated by SEM, XRD, EDS and electrochemical tests. After immersion, the weight loss was calculated and the magnetic properties of the samples were measured. Results showed that Ce affected the corrosion of the (Nd,Ce)FeB magnet. Compared with the NdFeB magnet without Ce but of the same grade as the magnetic energy product, (Nd,Ce)FeB magnet showed better corrosion resistance. With increased Ce content, the corrosion resistances and magnetic properties of (Nd,Ce)FeB magnets were investigated.

  3. Study of the growth of CeO2 nanoparticles onto titanate nanotubes

    Science.gov (United States)

    Marques, Thalles M. F.; Ferreira, Odair P.; da Costa, Jose A. P.; Fujisawa, Kazunori; Terrones, Mauricio; Viana, Bartolomeu C.

    2015-12-01

    We report the study of the growth of CeO2 nanoparticles on the external walls and Ce4+ intercalation within the titanate nanotubes. The materials were fully characterized by multiple techniques, such as: Raman spectroscopy, infrared spectroscopy (FTIR), energy dispersive spectroscopy (EDS), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM). The ion exchange processes in the titanate nanotubes were carried out using different concentrations of Ce4+ in aqueous solution. Our results indicate that the growth of CeO2 nanoparticles grown mediated by the hydrolysis in the colloidal species of Ce and the attachment onto the titanate nanotubes happened and get it strongly anchored to the titanate nanotube surface by a simple electrostatic interaction between the nanoparticles and titanate nanotubes, which can explain the small size and even distribution of nanoparticles on titanate supports. It was demonstrated that it is possible to control the amount and size of CeO2 nanoparticles onto the nanotube surface, the species of the Ce ions intercalated between the layers of titanate nanotubes, and the materials could be tuned for using in specific catalysis in according with the amount of CeO2 nanoparticles, their oxygen vacancies/defects and the types of Ce species (Ce4+ or Ce3+) present into the nanotubes.

  4. Nanocrystalline Mn-Mo-Ce Oxide Anode Doped Rare Earth Ce and Its Selective Electro-catalytic Performance

    Directory of Open Access Journals (Sweden)

    SHI Yan-hua

    2017-09-01

    Full Text Available The anode oxide of nanocrystalline Mn-Mo-Ce was prepared by anode electro-deposition technology, and its nanostructure and selective electro-catalytic performance were investigated using the SEM, EDS, XRD, HRTEM, electrochemical technology and oxygen evolution efficiency testing. Furthermore, the selective electro-catalytic mechanism of oxygen evolution and chlorine depression was discussed. The results show that the mesh-like nanostructure Mn-Mo-Ce oxide anode with little cerium doped is obtained, and the oxygen evolution efficiency for the anode in the seawater is 99.51%, which means a high efficiency for the selective electro-catalytic for the oxygen evolution. Due to the structural characteristics of γ-MnO2, the OH- ion is preferentially absorbed, while Cl- absorption is depressed. OH- accomplishes the oxygen evolution process during the valence transition electrocatalysis of Mn4+/Mn3+, completing the selective electro-catalysis process. Ce doping greatly increases the reaction activity, and promotes the absorption and discharge; the rising interplanar spacing between active (100 crystalline plane promotes OH- motion and the escape of newborn O2, so that the selective electro-catalytic property with high efficient oxygen evolution and chlorine depression is achieved from the nano morphology effect.

  5. Tetragonal Ce-based Ce-Sm(Fe, Co, Ti){sub 12} alloys for permanent magnets

    Energy Technology Data Exchange (ETDEWEB)

    Martin-Cid, Andres; Salazar, Daniel [BCMaterials, Bizkaia Science and Tecnology Park, 48160 Derio (Spain); Gabay, Aleksandr M.; Hadjipanayis, George C. [Department of Physics and Astronomy, University of Delaware, Newark, DE, 19716 (United States); Barandiaran, Jose Manuel [BCMaterials, Bizkaia Science and Tecnology Park, 48160 Derio (Spain); Department of Electricity and Electronics, University Basque Country (UPV/EHU), 48080 Bilbao (Spain)

    2016-12-15

    Abundance and relatively low cost of Ce provide a great incentive for its use in rare-earth permanent magnets. It has been recently reported that the tetragonal Ce(Fe,Co,Ti)12 compounds may exhibit application-worthy intrinsic magnetic properties. In this work the effect of the α-Fe phase formation due to the evaporation of Sm during alloy fabrication has been studied, as a previous step in the attempt to convert the intrinsic magnetic properties into functional properties of a permanent magnet. Ce{sub 0.5}Sm{sub 0.5}Fe{sub 9}Co{sub 2}Ti alloys based on the ThMn12-type crystal structure have been synthesized via melt-spinning with different Sm content. Coercive fields between 2.8 and 1.4 kOe have been found for α-Fe phase contents between 8 and 46% in volume, showing the influence of the α-Fe phase on the coercivity and exchange coupling between the hard and soft phase. (copyright 2016 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  6. Experimental and theoretical study about sulfur deactivation of Ni/ CeO{sub 2} and Rh/CeO{sub 2} catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Ocsachoque, Marco A., E-mail: ocmarco@quimica.unlp.edu.ar [Centro de Investigación y Desarrollo en Ciencias Aplicadas “Dr Jorge J. Ronco”, (CONICET, CCT La Plata), Departamento de Química, Facultad de Cs Exactas (UNLP), Calle 48 N° 257, 1900 La Plata (Argentina); Eugenio Russman, Juan I.; Irigoyen, Beatriz [Instituto de Tecnologías del Hidrógeno y Energías Sostenibles (ITHES), Departamento de Ingeniería Química, Facultad de Ingeniería (UBA), Buenos Aires (Argentina); Gazzoli, Delia [Dipartimento di Chimia, Universitá di Roma “La Sapienza”, Roma (Italy); González, María G. [Centro de Investigación y Desarrollo en Ciencias Aplicadas “Dr Jorge J. Ronco”, (CONICET, CCT La Plata), Departamento de Química, Facultad de Cs Exactas (UNLP), Calle 48 N° 257, 1900 La Plata (Argentina)

    2016-04-01

    Sulfur deactivation of Ni/CeO{sub 2} and Rh/CeO{sub 2} catalysts were examined through an experimental and theoretical study. These catalysts were characterized by N{sub 2} adsorption, X-ray diffraction, temperature programmed reaction, thermogravimetric analysis, Uv–visible spectroscopy and Raman spectroscopy, and tested under the methane dry reforming reaction in the presence of H{sub 2}S. On the other hand, different possible interactions of sulfur with Rh, Ni or surface sites of the CeO{sub 2} support were evaluated by performing energy calculations with the density functional theory (DFT). Overall, the results indicate that tolerance to sulfur of Rh/CeO{sub 2} catalyst is higher than that of Ni/CeO{sub 2} one. In this sense, TPR measurements show that reduction of CeO{sub 2} is promoted by the presence of Rh. This effect, probably caused by hydrogen spillover to CeO{sub 2} support during the reduction of RhO{sub x} species, could be linked to a high oxygen donation capacity of Rh/CeO{sub 2} catalysts. Accordingly, the O{sup 2−} species existing on Rh/CeO{sub 2} catalysts, revealed by Raman spectra of these samples, could favor sulfur oxidation and prevent Rh–S interactions. Likewise, the theoretical calculations show that desorption of S–O species from Rh/CeO{sub 2} system is more favorable than that from Ni/CeO{sub 2} one. Therefore, our experimental and theoretical study about sulfur deactivation of Ni and Rh supported on CeO{sub 2} allow us to postulate that Rh can help to desorb SO{sub x} species formed on the support, retarding sulfur poisoning of the Rh/CeO{sub 2} catalysts. - Highlights: • CeO{sub 2} support can act as a sacrifice trap decreasing sulfur poisoning. • Theoretical calculations indicate an important nickel affinity with sulfur. • Rh would favor desorption of S–O species formed on the support. • The O{sup 2−} species present on the Rh–CeO{sub 2} sample favor sulfur removal.

  7. Method for removing trace contaminants from multicurie amounts of 144Ce

    International Nuclear Information System (INIS)

    Wagner, J.A.; Kanapilly, G.M.

    1976-01-01

    Removal of contaminants from stock solutions of 144 Ce(III) was required for large quantities of 144 Ce prior to incorporation into fused aluminosilicate particles for inhalation toxicology studies. Since available procedures for purification of 144 Ce could not be readily adapted to our laboratory conditions and requirements, a simple procedure was developed to purify 144 Ce in multicurie quantities of 144 Ce(III). This procedure consists of separation of 144 Ce from contaminants by precipitation and filtrations at different pH. Its simplicity and efficacy in providing a stock solution that would readily exchange into montmorillonite clay was demonstrated when it was used during the preparation of large amounts of 144 Ce in fused aluminosilicate particles

  8. Facile preparation of self-healing superhydrophobic CeO2 surface by electrochemical processes

    Science.gov (United States)

    Nakayama, Katsutoshi; Hiraga, Takuya; Zhu, Chunyu; Tsuji, Etsushi; Aoki, Yoshitaka; Habazaki, Hiroki

    2017-11-01

    Herein we report simple electrochemical processes to fabricate a self-healing superhydrophobic CeO2 coating on Type 304 stainless steel. The CeO2 surface anodically deposited on flat stainless steel surface is hydrophilic, although high temperature-sintered and sputter-deposited CeO2 surface was reported to be hydrophobic. The anodically deposited hydrophilic CeO2 surface is transformed to hydrophobic during air exposure. Specific accumulation of contaminant hydrocarbon on the CeO2 surface is responsible for the transformation to hydrophobic state. The deposition of CeO2 on hierarchically rough stainless steel surface produces superhydrophobic CeO2 surface, which also shows self-healing ability; the surface changes to superhydrophilic after oxygen plasma treatment but superhydrophobic state is recovered repeatedly by air exposure. This work provides a facile method for preparing a self-healing superhydrophobic surface using practical electrochemical processes.

  9. Luminescent and scintillation properties of the Ce3+ doped Y3−xLuxAl5O12:Ce single crystalline films

    International Nuclear Information System (INIS)

    Zorenko, Yu.; Gorbenko, V.; Zorenko, T.; Popielarski, P.; Mosińska, L.; Fedorov, A.

    2016-01-01

    The work is related to the investigation of scintillation and luminescent properties of single crystalline films (SCF) of solid solutions of Ce 3+ doped Y 3−x Lu x Al 5 O 12 :Ce garnets with x value in the 0–3 range. We have shown a possibility of realization of high-energy shift of the Ce 3+ ion emission spectrum in these garnets up to 22 nm. We have also found that the light yield of the radioluminescence under α-particle excitation of LuAG:Ce SCF can exceed by 1.3 times the corresponding values for the YAG:Ce SCF counterpart. For investigation of the luminescent properties of Y 3−x Lu x Al 5 O 12 :Ce SCF at different x values the luminescent spectroscopy of these SCFs under excitation by synchrotron radiation in the VUV range was performed. - Highlights: • Single crystalline films of Y 3−x Lu x Al 5 O 12 garnets at x=0–3.0 were grown by LPE method onto YAG substrates. • Lattice constant of Y 3−x Lu x Al 5 O 12 :Ce film and the film/substrate misfit changed linearly with increasing of Lu content in the x=0–3.0 range. • High-energy shift of the Ce 3+ emission up to 22 nm in Y 3−x Lu x Al 5 O 12 film with increasing of Lu content in the x=0–3.0 range. • Light yield of Y 3−x Lu x Al 5 O 12 :Ce film decreases in the x=0–1.8 range and increases in the x=1.8–3.0 range. • Scintillation LY of Lu 3 Al 5 O 12 :Ce film can exceed by 1.3 times the LY for YAG:Ce film counterpart.

  10. Measurement of Ce(IV) Concentration in Foam Decontaminant containing Fluorosurfactant

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Chong Hun; Yang, H. B.; Yoon, I. H.; Choi, W. K.; Moon, J. K. [KAERI, Daejeon (Korea, Republic of); Lee, J. S. [Gachon University, Seongnam (Korea, Republic of)

    2016-05-15

    To improve the stability of the foam, surfactants and inorganic materials such as nanoparticles can be added. A nanoparticle-based foam decontaminant is composed of a surfactant and nanoparticles for the generation and maintenance of foam, and a chemical decontamination agent made of Ce(IV) dissolved in nitric acid. Ce(IV) will be reduced to Ce(III) through the decontamination process. Oxidizing the cerium (III) can be reused as a decontamination agent, Ce(IV). Oxidation treatment technology by ozone uses its strong oxidizing power. It can be regarded as an environmentally friendly process, because ozone cannot be stored and transported like other industrial gases (because it quickly decays into diatomic oxygen) and must therefore be produced on site, and used ozone can be decomposed immediately. A concentration analysis of Ce(IV) in foam decontaminant containing a surfactant is necessary prior to the derivation of optimal conditions for the regeneration of Ce(III) through ozonation treatment. A UV spectrometric method using the absorbance or potentiometric method with a potential difference in Ce(III)/Ce(IV), or a potentiometric titration method using Fe (II), can be used for a Ce(IV) concentration analysis. A UV spectrometric method has a problem receiving the influence of the surfactant, and a potentiometric method is difficult to use because of the problem of an insignificant change in the potential difference value of the Ce(III)/Ce(IV). Thus, the present study was undertaken to determine whether the potentiometric titration method can be used for an analysis of the Ce(IV) concentration in the nanoparticle-based foam decontaminant containing surfactant. It will be effectively used for the Ce(IV) concentration measurement, in relation to the subsequent research on the derivation of optimal conditions for the regeneration of Ce(III) through ozonation treatment.

  11. Ultraviolet and near-infrared luminescence of LaBO3:Ce3+,Yb3+

    Science.gov (United States)

    Wei, Heng-Wei; Shao, Li-Ming; Jiao, Huan; Jing, Xi-Ping

    2018-01-01

    Ce3+ or Yb3+ singly doped LaBO3 and Ce3+-Yb3+ co-doped LaBO3 were prepared by conventional solid state reactions at 1100 °C and their photoluminescence (PL) properties were investigated. The emission spectrum of LaBO3:Ce3+,Yb3+ contains both the Ce3+ ultraviolet (UV) emissions (355 nm and 380 nm) and the Yb3+ near infrared (NIR) emission (975 nm) when excited by the UV light at 270 nm. By using the data of the Ce3+ decay curves and the PL intensities of both Ce3+ and Yb3+, the energy transfer efficiency (η) from Ce3+ to Yb3+, the actual energy transfer efficiency (AE) and the quantum efficiency (Q) of the Yb3+ emission were calculated. In the Ce3+-Yb3+ co-doped LaBO3, Ce3+ can transfer its absorbed energy to Yb3+ efficiently (η can be over 60%), and Yb3+ shows the Q value over 50% when it accepts the energy from Ce3+, which results in the low AE value ∼30%. The energy transfer process from Ce3+ to Yb3+ may be understood by the charge transfer mechanism: Ce3+ + Yb3+ ↔ Ce4+ + Yb2+. Particularly the Ce3+-Yb3+ co-doped LaBO3 phosphor gives the emissions mainly in the UV range and the NIR range with a portion of visible emissions in eye-insensitive range. This unique property may be suitable for applications in anti-counterfeiting techniques and public security affairs.

  12. Electro-regeneration of Ce(IV) in real spent Cr-etching solutions

    International Nuclear Information System (INIS)

    Chen, Te-San; Huang, Kuo-Lin

    2013-01-01

    Highlights: • An electrochemical process is used to regenerate Ce(IV) in real (hazardous) spent TFT-LCD Cr-etching solutions. • The Ce(IV) yield on tested anodes was in order BDD > Pt > DSA. • A Neosepta CMX separator was better than Nafion ones to be used in the process. • The activation energy on Pt was 10.7 kJ/mol. • The obtained parameters are useful to design reactors for 100% Ce(IV) regeneration in real spent Cr-etching solutions. -- Abstract: This paper presents the electro-regeneration of Ce(IV) in real (hazardous) spent thin-film transistor liquid-crystal display (TFT-LCD) Cr-etching solutions. In addition to Ce(III) > Ce(IV) in diffusivity, a quasi-reversible behavior of Ce(III)/Ce(IV) was observed at both boron-doped diamond (BDD) and Pt disk electrodes. The Ce(IV) yield on Pt increased with increasing current density, and the best current efficiency (CE) was obtained at 2 A/2.25 cm 2 . The performance in terms of Ce(IV) yield and CE of tested anodes was in order BDD > Pt > dimensional stable anode (DSA). At 2 A/2.25 cm 2 on Pt and 40 °C for 90 min, the Ce(IV) yield, CE and apparent rate constant (k) for Ce(III) oxidation were 81.4%, 21.8% and 3.17 × 10 −4 s −1 , respectively. With the increase of temperature, the Ce(IV) yield, CE, and k increased (activation energy = 10.7 kJ/mol), but the specific electricity consumption decreased. The Neosepta CMX membrane was more suitable than Nafion-117 and Nafion-212 to be used as the separator of the Ce(IV) regeneration process. The obtained parameters are useful to design divided batch reactors for the Ce(IV) electro-regeneration in real spent Cr-etching solutions

  13. Glass forming ability of the Al-Ce-Ni system; Avaliacao da capacidade de formacao vitrea do sistema Al-Ce-Ni

    Energy Technology Data Exchange (ETDEWEB)

    Triveno Rios, C. [Engenharia Mecanica, Universidade Federal de Mato Grosso, Rondonopolis, MT (Brazil)], e-mail: triveno@ufmt.br; Surinach, S.; Baro, M.D. [Departamento de Engenharia de Materiais - Universidade Federal de Sao Carlos, SP (Brazil); Bolfarini, C.; Botta, W.J.; Kiminami, C.S. [Departamento de Fisica da Universidade Autonoma de Barcelona, Bellaterra (Spain)

    2010-07-01

    In the present work, the glass forming ability (GFA) and its compositional dependence on Al-Ni-Ce system alloys were investigated in function of several thermal parameters. Rapidly quenched Al{sub 85}Ni{sub 15}-{sub X}Ce{sub X} (X=4,5,6,7,10), Al{sub 90}Ni{sub 5}Ce{sub 5}, Al{sub 89}Ni{sub 2}.{sub 4}Ce{sub 8}.{sub 6}, Al{sub 80}Ni{sub 15.6}Ce{sub 4}.{sub 4} and Al{sub 78}Ni{sub 18.5}Ce{sub 3.5} amorphous ribbons were produced by melt-spinning and the structural transformation during heating was studied using a combination of X-ray diffraction (XRD) and differential scanning calorimetry (DSC). The results showed that the GFA and the thermal stability in the Al-rich corner of Al- Ni-Ce system alloys were enhanced by increasing the solute content and specifically the Ce content (author)

  14. Preparation and luminescence properties of Ce3+ and Ce3+/Tb(3+)-activated Y4Si2O7N2 phosphors.

    Science.gov (United States)

    Xia, Zhiguo; Wu, Weiwei

    2013-09-28

    Ce(3+) and Ce(3+)/Tb(3+)-activated Y4Si2O7N2 phosphors are synthesized by the solid-state method, which can be efficiently excited by near ultraviolet (UV) light emitting diode (LED) chips. The PL spectrum of Y4Si2O7N2:Ce(3+) shows a broad hump between 380 and 650 nm, assigned to the electron transition from the 4f energy level to different 5d sub levels of the Ce(3+) ions at different Y(3+) sites. The color of the Y4Si2O7N2:Ce(3+) phosphor can shift from blue to green by introducing Tb(3+). In addition, the energy transfer process from Ce(3+) to Tb(3+) in the Y4Si2O7N2 host was investigated and discussed in terms of both the luminescence spectra and decay curves. The energy transfer critical distance has been calculated and evaluated by the concentration quenching method. Therefore, the Ce(3+) and Ce(3+)/Tb(3+)-activated Y4Si2O7N2 phosphors can serve as key materials for phosphor-converted white-light UV-LEDs.

  15. Transitions between localized and itinerant antiferromagnetism in the Ce(Pb,In) sub 3 and Ce(Pb,Tl) sub 3 systems

    Energy Technology Data Exchange (ETDEWEB)

    Rahman, S; Timlin, J; Crow, J E; Mihalisin, T; Schlottmann, P [Temple Univ., Philadelphia, PA (United States)

    1990-01-01

    CePb{sub 3} is an itinerant heavy fermion antiferromagnetic displaying an incommensurate magnetic structure and an extremely small ordered moment. CeIn{sub 3} and CeTl{sub 3}, on the other hand are well-localized, simple antiferromagnets with the full moments expected for crystal field doublet Ce{sup 3+} ion systems. The authors have performed specific heat, sysceptibility and resistivity measurements for both the Ce(Pb,In){sub 3} and Ce(Pb,Tl){sub 3} systems. These systems remain cubic Cu{sub 3}Au structures across the entire series. They display extremely interesting T{sub N} behavior which suggests that a continuous transition from itinerant to localized antiferromagnetic behavior occurs for the Ce(Pb,Tl){sub 3} system. In the Ce (Pb,In){sub 3} system both types of antiferromagnetism are present but they are separated by a concentration range ({approximately}10-40% Pb) over which antiferromagnetism does not exist. The behavior of these systems cannot be accounted for by a Kondo necklace approach that neglects the coherence of a heavy fermion lattice and resulting itinerant antiferromagnetism.

  16. Effects of Ce3+ concentration, beam voltage and current on the cathodoluminescence intensity of SiO2: Pr3+–Ce3+ nanophosphor

    CSIR Research Space (South Africa)

    Mhlongo, GH

    2011-02-01

    Full Text Available SiO2:Pr3+–Ce3+ phosphor powders were successfully prepared using a sol–gel process. The concentration of Pr3+ was fixed at 0.2 mol% while that of Ce3+ was varied in the range of 0.2–2 mol%. High resolution transmission electron microscopy (HRTEM...

  17. Study of magnetic properties of TGa6 with T = Ce, Pr, Nd, Tb, Ho, Dy and of solid solutions Ce(Ga1-x Alx)2

    International Nuclear Information System (INIS)

    Jerjini, M.

    1987-10-01

    At low temperature TGa 6 compounds are ordered with a Neel temperature of about 10 K. Magnetic structures are antiferromagnetic for T = Pr or Nd or modulated for T = Tb, Ho or Dy. Ce presents an abnormal behavior in CeGa 6 . Neutron inelastic scattering allows the determination of energy levels in the crystal field of cerium ion and evidences hybridation of 4f and valence electrons. Three magnetic transitions for T 6 . Study of CeGa 6 and solid solutions. Ce(Ga (1-x) Al x ) 2 shows that aluminium insertion reinforces the Kondo effect. For x = O.1 an incommensurable structure subsists at very low temperature. CeGa 2 is ordered with 3 magnetic structures. Magnetic moment is reduced with Al. The study of crystal field by neutron scattering shows that hybridation effects are more important for the compound with x = 0.1 [fr

  18. Tunable colorimetric performance of Al{sub 2}O{sub 3}-YAG:Ce{sup 3+} eutectic crystal by Ce{sup 3+} concentration

    Energy Technology Data Exchange (ETDEWEB)

    Sai, Qinglin, E-mail: saiql@siom.ac.cn; Xia, Changtai, E-mail: xia_ct@siom.ac.cn

    2017-06-15

    Ce-doped Al{sub 2}O{sub 3}-YAG eutectics with different percentage of Ce were successfully grown by the optical floating zone technique. X-ray diffraction (XRD) and scanning electron microscopy (SEM) were used to investigate the structure. The results show that they have typical eutectic structure of interpenetrating sapphire and garnet phases with the tens of microns lamella spacing. The photoluminescence spectra of the eutectics showed that they have wide excitation band, and samples with 1.6 mol% Ce-doped has the highest emission intensity. The eutectic-packaged LED has high luminous efficiency and its color can be modulated by changing Ce concentration. The results reveal that Ce-doped Al{sub 2}O{sub 3}-YAG eutectic is a promising phosphor for white LED applications.

  19. Pseudogenes regulate parental gene expression via ceRNA network.

    Science.gov (United States)

    An, Yang; Furber, Kendra L; Ji, Shaoping

    2017-01-01

    The concept of competitive endogenous RNA (ceRNA) was first proposed by Salmena and colleagues. Evidence suggests that pseudogene RNAs can act as a 'sponge' through competitive binding of common miRNA, releasing or attenuating repression through sequestering miRNAs away from parental mRNA. In theory, ceRNAs refer to all transcripts such as mRNA, tRNA, rRNA, long non-coding RNA, pseudogene RNA and circular RNA, because all of them may become the targets of miRNA depending on spatiotemporal situation. As binding of miRNA to the target RNA is not 100% complementary, it is possible that one miRNA can bind to multiple target RNAs and vice versa. All RNAs crosstalk through competitively binding to miRNAvia miRNA response elements (MREs) contained within the RNA sequences, thus forming a complex regulatory network. The ratio of a subset of miRNAs to the corresponding number of MREs determines repression strength on a given mRNA translation or stability. An increase in pseudogene RNA level can sequester miRNA and release repression on the parental gene, leading to an increase in parental gene expression. A massive number of transcripts constitute a complicated network that regulates each other through this proposed mechanism, though some regulatory significance may be mild or even undetectable. It is possible that the regulation of gene and pseudogene expression occurring in this manor involves all RNAs bearing common MREs. In this review, we will primarily discuss how pseudogene transcripts regulate expression of parental genes via ceRNA network and biological significance of regulation. © 2016 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.

  20. Catalytic reforming of toluene as tar model compound: effect of Ce and Ce-Mg promoter using Ni/olivine catalyst.

    Science.gov (United States)

    Zhang, Ruiqin; Wang, Huajian; Hou, Xiaoxue

    2014-02-01

    Tar produced by biomass gasification as a route of renewable energy must be removed before the gas can be used. This study was undertaken using toluene as a model tar compound for evaluating its steam reforming conversion with three Ni-based catalysts, Ni/olivine, Ni-Ce/olivine and Ni-Ce-Mg/olivine. Effects of Ce and Mg promoters on the reaction activity and coke deposition were studied. Overall the performance of Ce and Mg promoted Ni/olivine catalysts is better than that of only Ce promoter and Ni/olivine alone. The experimental results indicate that Ni-Ce-Mg/olivine catalysts could improve the resistance to carbon deposition, enhance energy gases yield and resist 10ppm H2S poison at 100mLmin(-1) for up to 400min. Furthermore, the activity of catalysts was related to the steam/carbon (S/C) ratios; at S/C ratio=5, T=790°C, space velocity=782h(-1) and t=2h, the Ni-Ce-Mg/olivine system yielded 89% toluene conversion, 5.6Lh(-1) product gas rate, 62.6mol% H2 content and 10% (mol useful gas mol(-1) toluene) energy yield. Moreover, at low S/C ratio, it had higher reaction activity and better ability to prevent coking. There is a small amount of carbon deposition in the form of amorphous carbon after 7h. Various characterization techniques such as XRD, FTIR and thermogravimetric were performed to investigate the coke deposition of Ni/olivine, Ni-Ce/olivine and Ni-Ce-Mg/olivine. It is suggested that 3% Ni-1% Ce-1% Mg/olivine was the most promising catalyst due to its minimum coke amount and the lower activation energy of coke burning. Copyright © 2014. Published by Elsevier Ltd.

  1. Decay pattern of the Pygmy Dipole Resonance in 140Ce

    Science.gov (United States)

    Isaak, J.; Löher, B.; Savran, D.; Aumann, T.; Beller, J.; Cooper, N.; Derya, V.; Duchêne, M.; Endres, J.; Fiori, E.; Kelley, J. H.; Knörzer, M.; Pietralla, N.; Ponomarev, V. Yu.; Romig, C.; Scheck, M.; Scheit, H.; Silva, J.; Tonchev, A. P.; Tornow, W.; Weller, H. R.; Werner, V.; Zilges, A.; Zweidinger, M.

    2015-05-01

    The decay behavior of low-lying dipole states in 140Ce was investigated exploiting the γ3-setup at the HIγS facility using quasi-monochromatic photon beams. Branching ratios of individual excited states as well as average branching ratios to low-lying states have been extracted using γ - γ coincidence measurements. The comparison of the average branching ratios to QPM calculations shows a remarkable agreement between experiment and theory in the energy range from 5.0 to 8.5 MeV.

  2. Detailed spectroscopy of the normally deformed states in 132Ce

    International Nuclear Information System (INIS)

    Paul, E.S.; Gizon, A.; Gizon, J.; Santos, D.; Nyako, B.M.; O'Brien, N.J.; Parry, C.M.; Wadsworth, R.

    1997-01-01

    High-spin states have been studied in 132 Ce produced in the 100 Mo( 36 S,4nγ) reaction using the EUROGAM II spectrometer. The structure of the normally deformed states (β 2 ∝0.2) has been investigated. Eight ΔI=2 bands and three ΔI=1 bands have been identified and the level scheme extended up to spin and parity (40 + ) at an excitation energy 19.79 MeV. The results are interpreted with the aid of Woods-Saxon cranking calculations, which suggest a variety of triaxial (γ) shapes in this nucleus stabilised by specific active quasiparticle orbitals. (orig.)

  3. Fast humidity sensors based on CeO2 nanowires

    International Nuclear Information System (INIS)

    Fu, X Q; Wang, C; Yu, H C; Wang, Y G; Wang, T H

    2007-01-01

    Fast humidity sensors are reported that are based on CeO 2 nanowires synthesized by a hydrothermal method. Both the response and recovery time are about 3 s, and are independent of the humidity. The sensitivity increases gradually as the humidity increases, and is up to 85 at 97% RH. The resistance decreases exponentially with increasing humidity, implying ion-type conductivity as the humidity sensing mechanism. A model based on the morphology and surface energy of the nanowires is given to explain these results further. Our experimental results indicate a pathway to improving the performance of humidity sensors

  4. Microscopic IBM-1 description of collective states in 128Ce

    Directory of Open Access Journals (Sweden)

    Mikhajlov V. M.

    2012-12-01

    Full Text Available Microscopical quasiparticle theory is developed to calculate the IBM-1 parameters entering the Hamiltonian and E2–operator. The theory takes into account the impact of noncollective phonons and predicts alterations of the superconducting properties along the excitation spectrum, whereas the most collective phonon (the image of the IBM d-boson is practically invariable. Calculations of the energy spectrum and probabilities of E2–transitions (without effective nucleon charges were performed for 128Ce. The results obtained are in satisfactory agreement with experimental data.

  5. Fundamentals of electrochemical detection techniques for CE and MCE.

    Science.gov (United States)

    Kubán, Pavel; Hauser, Peter C

    2009-10-01

    The electroanalytical techniques of amperometry, conductometry and potentiometry match well with the instrumental simplicity of CE. Indeed, all three detection approaches have been reported for electrophoretic separations. However, the characteristics of the three methods are quite distinct and these are not related to the optical methods more commonly employed. A detailed discussion of the underlying principles of each is given. The issue of possible effects of the separation voltage on the electrochemical detection techniques is considered in depth, and approaches to the elimination of such interferences are also discussed for each case.

  6. Live births profile, Maranguape – CE from 2000 to 2003

    OpenAIRE

    Nancy Costa de Oliveira; Escolástica Rejane Ferreira Moura; Cristiana Ferreira da Silva

    2012-01-01

    It was objectified to analyze the profile of the live births in Maranguape-CE registered in the Live Births Information System (SINASC) between January, 2000 and December, 2003.5.032 declarations of live births (DN) of resident mother were analyzed. The DN was included in the SINASC Software of the Health Ministry and the data were presented in tabular format. The maternal age between 21 and 30 was predominant, education between4 and 11 years of study, the increase in the percentage of single...

  7. Programming Windows® Embedded CE 60 Developer Reference

    CERN Document Server

    Boling, Douglas

    2010-01-01

    Get the popular, practical reference to developing small footprint applications-now updated for the Windows Embedded CE 6.0 kernel. Written by an authority on embedded application development, this book focuses in on core operating concepts and the Win32 API. It delivers extensive code samples and sample projects-helping you build proficiency creating innovative Windows applications for a new generation of devices. Discover how to: Create complex applications designed for the unique requirements of embedded devicesManage virtual memory, heaps, and the stack to minimize your memory footprintC

  8. espèce de tilapia Sarotherodon melanotheron melanothero

    African Journals Online (AJOL)

    Sci-Nat

    melanotheron, objet du présent travail, dont l'aire de répartition s'étend de la Côte d'Ivoire au. Cameroun. En Côte d'Ivoire, ce poisson se rencontre dans les estuaires et eaux saumâtres, depuis le fleuve Cavally (à l'Ouest) à la lagune. Aby (à l'Est) mais aussi en amont du lac de barrage du fleuve Bia (Gourène et al., 1999).

  9. Decay pattern of the Pygmy Dipole Resonance in 140Ce

    Directory of Open Access Journals (Sweden)

    Isaak J.

    2015-01-01

    Full Text Available The decay behavior of low-lying dipole states in 140Ce was investigated exploiting the γ3-setup at the HIγS facility using quasi-monochromatic photon beams. Branching ratios of individual excited states as well as average branching ratios to low-lying states have been extracted using γ – γ coincidence measurements. The comparison of the average branching ratios to QPM calculations shows a remarkable agreement between experiment and theory in the energy range from 5.0 to 8.5 MeV.

  10. Magnetization at high pressure in CeP

    Science.gov (United States)

    Naka, T.; Matsumoto, T.; Okayama, Y.; Môri, N.; Haga, Y.; Suzuki, T.

    1995-02-01

    We have investigated the pressure dependence of magnetization below 60 K up to 1.6 GPa in the low-carrier concentration system CeP showing two step transitions at T = TL and TH under high pressure. At high pressure, M( P, T) exhibits a maximum at around the lower transition temperature TL. This behavior implies that the magnetic state changes at TL. The pressure dependence of isothermal magnetization M( P) is different above and below TL. In fact, M( P) below TL exhibits a maximum at around 1.4 GPa, whereas M( P) above TL increases steeply with pressure up to 1.6 GPa.

  11. Properties of Ce-doped ITO films deposited on polymer substrate by DC magnetron sputtering

    International Nuclear Information System (INIS)

    Kang, Y.M.; Kwon, S.H.; Choi, J.H.; Cho, Y.J.; Song, P.K.

    2010-01-01

    Ce-doped indium tin oxide (ITO:Ce) films were deposited on flexible polyimide substrates by DC magnetron sputtering using ITO targets containing various CeO 2 contents (CeO 2 : 0, 0.5, 3.0, 4.0, 6.0 wt.%) at room temperature and post-annealed at 200 o C. The crystallinity of the ITO films decreased with increasing Ce content, and it led to a decrease in surface roughness. In addition, a relatively small change in resistance in dynamic stress mode was obtained for ITO:Ce films even after the annealing at high temperature (200 o C). The minimum resistivity of the amorphous ITO:Ce films was 3.96 x 10 -4 Ωcm, which was deposited using a 3.0 wt.% CeO 2 doped ITO target. The amorphous ITO:Ce films not only have comparable electrical properties to the polycrystalline films but also have a crystallization temperature > 200 o C. In addition, the amorphous ITO:Ce film showed stable mechanical properties in the bended state.

  12. Scientific Objectives of China Chang E 4 CE-4 Lunar Far-side Exploration Mission

    Science.gov (United States)

    Zhang, Hongbo; Zeng, Xingguo; Chen, Wangli

    2017-10-01

    China has achieved great success in the recently CE-1~CE-3 lunar missions, and in the year of 2018, China Lunar Exploration Program (CLEP) is going to launch the CE-4 mission. CE-4 satellite is the backup satellite of CE-3, so that it also consists of a Lander and a Rover. However, CE-4 is the first mission designed to detect the far side of the Moon in human lunar exploration history. So the biggest difference between CE-4 and CE-3 is that it will be equipped with a relay satellite in Earth-Moon-L2 Point for Earth-Moon Communication. And the scientific payloads carried on the Lander and Rover will also be different. It has been announced by the Chinese government that CE-4 mission will be equipped with some new international cooperated scientific payloads, such as the Low Frequency Radio Detector from Holland, Lunar Neutron and Radiation Dose Detector from Germany, Neutral Atom Detector from Sweden, and Lunar Miniature Optical Imaging Sounder from Saudi Arabia. The main scientific objective of CE-4 is to provide scientific data for lunar far side research, including: 1)general spatial environmental study of lunar far side;2)general research on the surface, shallow layer and deep layer of lunar far side;3)detection of low frequency radio on lunar far side using Low Frequency Radio Detector, which would be the first time of using such frequency band in lunar exploration history .

  13. Mesoporous CeTiSiMCM-48 as novel photocatalyst for degradation of organic compounds

    International Nuclear Information System (INIS)

    Mureseanu, Mihaela; Parvulescu, Viorica; Radu, Teodora; Filip, Mihaela; Carja, Gabriela

    2015-01-01

    This work presents novel photocatalysts containing Ti and/or Ce embedded in the mesoporous silica framework (TiSiMCM-48, CeSiMCM-48 and CeTiSiMCM-48) that were prepared via a facile sol–gel process in the presence of ionic structure directing agents. The structural properties of the obtained materials were analyzed by X-ray diffraction (XRD), nitrogen adsorption-desorption, scanning and transmission electron microscopy (SEM, TEM), EDAX analysis, X-ray photoelectron microscopy (XPS), ultraviolet–visible diffuse reflectance spectroscopy (UV–vis DRS) and Fourier transformation infrared spectroscopy (FT-IR). The results indicated that Ce and Ti were highly dispersed or incorporated into the framework of the cubic SiMCM-48, with an enhanced light-trapping effect both in the UV and Vis regions. When applied to the photocatalytic degradation of phenol, the best results were obtained for the bimetallic hybrid. The best activity of CeTiSiMCM-48 photocatalyst was ascribed to improved electron–hole pair separation efficiency and formation of more reactive oxygen species due to the presence of Ce 4+ /Ce 3+ . The mesoporous support increases the dispersability of the photoactive Ti 4+ or Ce 4+ /Ce 3+ species on the catalyst surface and the accessibility of the substrate to the active sites. Furthermore, the catalysts can be easily recovered and reused for four cycles without significant loss of activity. - Highlights: • Novel photocatalysts containing Ti and/or Ce embedded in the mesoporous MCM-48 silica. • Ce 4+ /Ce 3+ improved electron–hole pair separation and reactivity of oxygen species. • The mesoporous support increases the dispersability of the photoactive species. • The photocatalyst was highly active and stable for phenol degradation under UV irradiation. • TiCeSiMCM-48 can be recycled up to four cycles without significant loss of activity

  14. Highly active and durable Ca-doped Ce-SBA-15 catalyst for biodiesel production

    International Nuclear Information System (INIS)

    Thitsartarn, Warintorn; Maneerung, Thawatchai; Kawi, Sibudjing

    2015-01-01

    In this work, Ca-doped Ce-incorporated SBA-15 (Ca/CeS) catalyst was successfully synthesized by using direct synthesis of Ce-incorporated SBA-15 followed by impregnation of CaO (calcium oxide). The maximum Si/Ce molar ratio that Ce atoms can be incorporated successfully into the mesoporous framework was found to be 5 (CeS-5). After the impregnation of 30 wt. % Ca, the obtained 30Ca/CeS-5 catalysts showed the superior catalytic performance for transesterification reaction of palm oil with methanol and also the higher catalytic activity as compared to other supported catalysts, i.e. CaO/CeO 2 and CaO–CeO 2 /SBA-15. This can be attributed to the well-dispersion of CaO on the CeS-5 support surface. Furthermore, it was found that the leaching of Si, Ce and Ca from the catalyst into biodiesel produced was negligible (i.e. <1 ppm after 7 cycles), indicating the strong interaction between CaO and CeS-5 support. As a result, the 30Ca/CeS-5 catalyst can be reused at least 15 cycles with insignificant decrease in catalytic activity, offering the efficient CaO-based catalyst for biodiesel production. - Highlights: • Mesoporous Ca-based catalyst was successfully developed for biodiesel production. • Catalyst exhibited high activity towards transesterification (FAME yield > 98%). • Catalyst can be effectively re-used at least 15 cycles. • Extremely low catalyst contaminant (<1 ppm) was presented

  15. Sonocatalytic degradation of diclofenac with FeCeOx particles in water.

    Science.gov (United States)

    Chong, Shan; Zhang, Guangming; Wei, Zhongheng; Zhang, Nan; Huang, Ting; Liu, Yucan

    2017-01-01

    This paper studies the sonocatalytic degradation of diclofenac in water using FeCeO x -catalyzed ultrasound. The effects of pre-adsorption and gas addition were investigated. Nitrogen adsorption/desorption, SEM, XRD, Raman and XPS analyses of FeCeO x before and after sonication were characterized. The proposed mechanism was based on the microstructure changes of FeCeO x and reactive-species-scavenging performances. The results show that FeCeO x has excellent performance in catalyzing an ultrasonic system in water, and 80% of diclofenac was removed in 30min ([Diclofenac]=20mg/L, FeCeO x amount=0.5g/L, pH=6, ultrasonic density=3.0W/cm 3 , ultrasonic frequency=20kHz, temperature=298K). The Fe, Ce, and O elements remained highly dispersed in the structure of FeCeO x , and the solid solution structure of FeCeO x remained stable after the reaction. Ce (III) was gradually oxidized to Ce (IV) and Fe (III) was gradually reduced to Fe (II) after the reaction, which indicates that Fe and Ce ions with different valences coexisted in dynamic equilibrium. The amount of oxygen vacancies in FeCeO x significantly decreased after the reaction, which indicates that oxygen vacancy participated in the ultrasonic process. Singlet oxygen 1 O 2 was the primary reactive species in the degradation process, and the hydroxyl radicals OH and superoxide radical anion O 2 - also participated in the reaction. FeCeO x had excellent chemical stability with negligible leaching ions in the ultrasonic process. Copyright © 2016 Elsevier B.V. All rights reserved.

  16. Synthesis, characterization, and ecotoxicity of CeO{sub 2} nanoparticles with differing properties

    Energy Technology Data Exchange (ETDEWEB)

    Alam, Bushra [Aero Shade Technologies Inc (United States); Philippe, Allan, E-mail: philippe@uni-landau.de; Rosenfeldt, Ricki R.; Seitz, Frank [University of Koblenz-Landau, Group of Environmental and Soil Chemistry, Institute for Environmental Sciences (Germany); Dey, Sonal [SUNY Polytechnic Institute, Colleges of Nanoscale Science and Engineering (United States); Bundschuh, Mirco; Schaumann, Gabriele E. [University of Koblenz-Landau, Group of Environmental and Soil Chemistry, Institute for Environmental Sciences (Germany); Brenner, Sara A. [SUNY Polytechnic Institute, Colleges of Nanoscale Science and Engineering (United States)

    2016-10-15

    CeO{sub 2} nanoparticles with various characteristics find an increasing number of applications in the electronic, medical, and other industries and are therefore likely released in the environment. This calls for investigations linking the physicochemical properties of these particles with their potential environmental impacts. In this study, CeO{sub 2} nanoparticle powders were prepared using three different precursors [Ce(NO{sub 3}){sub 3}, CeCl{sub 3}, and Ce(CH{sub 3}COO){sub 3}] and annealing temperatures (300, 500, and 700 °C). This procedure resulted in nine different types of nanoparticles with differing size (5–90 nm), morphology, surface Ce{sup 3+}/Ce{sup 4+} ratio, and slightly different crystal structures as characterized using transmission electron microscopy, dynamic light scattering, X-ray photoelectron spectroscopy, and X-ray diffraction measurements with Rietveld refinement. These CeO{sub 2} nanoparticles underwent toxicity testing at concentrations up to 64 mg L{sup −1} using Daphnia magna. Toxic effects were observed for three particle types with EC50 values between 5 and 64 mg L{sup −1}. No clear correlation was observed between the physicochemical properties (size, shape, oxygen occupancy, Ce{sup 3+}/Ce{sup 4+} ratio) of the nanoparticles and their toxicity. However, toxicity was correlated with the amount of Ce remaining suspended in the test medium after 24 h. This indicated that toxic effects may depend on the colloidal stability of CeO{sub 2} nanoparticles during the first day of exposure. Therefore, being readily suspended and remaining stable for several days in the aquatic media increases the likelihood that CeO{sub 2} nanoparticles will cause unwanted adverse effects.

  17. Electronic structure of heavy fermion system CePt2In7 from angle-resolved photoemission spectroscopy

    International Nuclear Information System (INIS)

    Shen Bing; Yu Li; Lyu Shou-Peng; Jia Xiao-Wen; Zhang Yan; Wang Chen-Lu; Hu Cheng; Ding Ying; Sun Xuan; Hu Yong; Liu Jing; Gao Qiang; Zhao Lin; Liu Guo-Dong; Liu Kai; Lu Zhong-Yi; Bauer, E D; Thompson, J D; Xu Zu-Yan; Chen Chuang-Tian

    2017-01-01

    We have carried out high-resolution angle-resolved photoemission measurements on the Ce-based heavy fermion compound CePt 2 In 7 that exhibits stronger two-dimensional character than the prototypical heavy fermion system CeCoIn 5 . Multiple Fermi surface sheets and a complex band structure are clearly resolved. We have also performed detailed band structure calculations on CePt 2 In 7 . The good agreement found between our measurements and the calculations suggests that the band renormalization effect is rather weak in CePt 2 In 7 . A comparison of the common features of the electronic structure of CePt 2 In 7 and CeCoIn 5 indicates that CeCoIn 5 shows a much stronger band renormalization effect than CePt 2 In 7 . These results provide new information for understanding the heavy fermion behaviors and unconventional superconductivity in Ce-based heavy fermion systems. (paper)

  18. EPA RE-Powering Mapper Feasibility Studies

    Data.gov (United States)

    U.S. Environmental Protection Agency — The U.S. Environmental Protection Agency (EPA) Office of Land and Emergency Management (OLEM) Office of Communications, Partnerships and Analysis (OCPA) initiated...

  19. EPA RE-Powering Mapper Region 7

    Data.gov (United States)

    U.S. Environmental Protection Agency — The U.S. Environmental Protection Agency (EPA) Office of Land and Emergency Management (OLEM) Office of Communications, Partnerships and Analysis (OCPA) initiated...

  20. EPA RE-Powering Mapper Large Scale

    Data.gov (United States)

    U.S. Environmental Protection Agency — The U.S. Environmental Protection Agency (EPA) Office of Land and Emergency Management (OLEM) Office of Communications, Partnerships and Analysis (OCPA) initiated...

  1. EPA RE-Powering Mapper Region 6

    Data.gov (United States)

    U.S. Environmental Protection Agency — The U.S. Environmental Protection Agency (EPA) Office of Land and Emergency Management (OLEM) Office of Communications, Partnerships and Analysis (OCPA) initiated...

  2. EPA RE-Powering Mapper Region 8

    Data.gov (United States)

    U.S. Environmental Protection Agency — The U.S. Environmental Protection Agency (EPA) Office of Land and Emergency Management (OLEM) Office of Communications, Partnerships and Analysis (OCPA) initiated...

  3. EPA RE-Powering Mapper Region 5

    Data.gov (United States)

    U.S. Environmental Protection Agency — The U.S. Environmental Protection Agency (EPA) Office of Land and Emergency Management (OLEM) Office of Communications, Partnerships and Analysis (OCPA) initiated...

  4. EPA RE-Powering Mapper Region 3

    Data.gov (United States)

    U.S. Environmental Protection Agency — The U.S. Environmental Protection Agency (EPA) Office of Land and Emergency Management (OLEM) Office of Communications, Partnerships and Analysis (OCPA) initiated...

  5. 75 FR 11841 - Repowering Assistance Program

    Science.gov (United States)

    2010-03-12

    ..., and where applicable, sex, marital status, familial status, parental status, religion, sexual orientation, genetic information, political beliefs, reprisal, or because all or part of an individual's...

  6. EPA RE-Powering Mapper Completed Installations

    Data.gov (United States)

    U.S. Environmental Protection Agency — The U.S. Environmental Protection Agency (EPA) Office of Land and Emergency Management (OLEM) Office of Communications, Partnerships and Analysis (OCPA) initiated...

  7. EPA RE-Powering Mapper Region 9

    Data.gov (United States)

    U.S. Environmental Protection Agency — The U.S. Environmental Protection Agency (EPA) Office of Land and Emergency Management (OLEM) Office of Communications, Partnerships and Analysis (OCPA) initiated...

  8. EPA RE-Powering Mapper Region 10

    Data.gov (United States)

    U.S. Environmental Protection Agency — The U.S. Environmental Protection Agency (EPA) Office of Land and Emergency Management (OLEM) Office of Communications, Partnerships and Analysis (OCPA) initiated...

  9. EPA RE-Powering Mapper Region 4

    Data.gov (United States)

    U.S. Environmental Protection Agency — The U.S. Environmental Protection Agency (EPA) Office of Land and Emergency Management (OLEM) Office of Communications, Partnerships and Analysis (OCPA) initiated...

  10. EPA RE-Powering Mapper Utility Scale

    Data.gov (United States)

    U.S. Environmental Protection Agency — The U.S. Environmental Protection Agency (EPA) Office of Land and Emergency Management (OLEM) Office of Communications, Partnerships and Analysis (OCPA) initiated...

  11. EPA RE-Powering Mapper Region 2

    Data.gov (United States)

    U.S. Environmental Protection Agency — The U.S. Environmental Protection Agency (EPA) Office of Land and Emergency Management (OLEM) Office of Communications, Partnerships and Analysis (OCPA) initiated...

  12. EPA RE-Powering Mapper Region 1

    Data.gov (United States)

    U.S. Environmental Protection Agency — The U.S. Environmental Protection Agency (EPA) Office of Land and Emergency Management (OLEM) Office of Communications, Partnerships and Analysis (OCPA) initiated...

  13. Structural aspects of the new quasi-2-D heavy fermion materials CeIrIns and CeRhIns

    International Nuclear Information System (INIS)

    Moshopoulou, E.G.; Moshopoulou, E.G.; Fisk, Z.; Sarrao, J.L.; Thompson, J.D.; Fisk, Z.

    2002-01-01

    The title compounds are new heavy fermion materials. They adopt a quasi two-dimensional crystal structure and exhibit unusual (for a heavy fermion system) low temperature properties. Although the study of their physical and structural behaviour at low temperatures and/or high pressures is still in progress, we present here some results concerning their average crystal structure, and we discuss very briefly their similarities and differences with the compounds CeIn3 and UTGa 5 (T: Co, Ni, Ir, Pd, Cu, Ru). (authors)

  14. The upper critical field of CeCoIn5

    International Nuclear Information System (INIS)

    Howald, Ludovic; Knebel, Georg; Aoki, Dai; Lapertot, Gérard; Brison, Jean-Pascal

    2011-01-01

    We present a detailed analysis of the upper critical field for CeCoIn 5 under high pressure. We show that, consistent with other measurements, this system shows a decoupling between the maximum of the superconducting transition temperature T c and the maximum pairing strength. We propose a model in which, in order to account for the discrepancy in pressure between the maximum of the upper critical field and the maximum of T c , we introduce magnetic pair-breaking effects, already widely suggested by other measurements. We found that within the Eliashberg frame work, the unusual shape of H c2 (T) can be completely reproduced when magnetic pair breaking is taken into account. Surprisingly, we found that the maximum of pair breaking and of pair coupling coincide in pressure, suggesting that both mechanisms originate from quantum criticality. Our model implies that CeCoIn 5 is the first compound of its family that shows clear decoupling between the maximum of T c and quantum criticality. (paper)

  15. What was the population of Great Zimbabwe (CE1000 - 1800)?

    Science.gov (United States)

    Chirikure, Shadreck; Moultrie, Thomas; Bandama, Foreman; Dandara, Collett; Manyanga, Munyaradzi

    2017-01-01

    The World Heritage Site of Great Zimbabwe is one of the most iconic and largest archaeological settlements in Africa. It was the hub of direct and indirect trade which internally connected various areas of southern Africa, and externally linked them with East Africa and the Near and Far East. Archaeologists believe that at its peak, Great Zimbabwe had a fully urban population of 20,000 people concentrated in approximately 2.9 square kilometres (40 percent of 720 ha). This translates to a population density of 6,897, which is comparable with that of some of the most populous regions of the world in the 21st century. Here, we combine archaeological, ethnographic and historical evidence with ecological and statistical modelling to demonstrate that the total population estimate for the site's nearly 800-year occupational duration (CE1000-1800), after factoring in generational succession, is unlikely to have exceeded 10,000 people. This conclusion is strongly firmed up by the absence of megamiddens at the site, the chronological differences between several key areas of the settlement traditionally assumed to be coeval, and the historically documented low populations recorded for the sub-continent between CE1600 and 1950.

  16. CE-4 Mission and Future Journey to Lunar

    Science.gov (United States)

    Zou, Yongliao; Wang, Qin; Liu, Xiaoqun

    2016-07-01

    Chang'E-4 mission, being undertaken by phase two of China Lunar Exploration Program, represents China's first attempt to explore farside of lunar surface. Its probe includes a lander, a rover and a telecommunication relay which is scheduled to launch in around 2018. The scientific objectives of CE-4 mission will be implemented to investigate the lunar regional geological characteristics of landing and roving area, and also will make the first radio-astronomy measurements from the most radio-quiet region of near-earth space. The rover will opreate for at least 3 months, the lander for half a year, and the relay for no less than 3 years. Its scinetific instruments includes Cameras, infrared imaging spectrometer, Penetrating Radar onboard the rover in which is the same as the paylads on board the CE-3 rover, and a Dust-analyzer, a Temperature-instrument and a Wide Band Low Frequency Digital Radio Astronomical Station will be installed on board the lander. Our scientific goals of the future lunar exploration will aim at the lunar geology, resources and surface environments. A series of exploraion missions such as robotic exploration and non-manned lunar scientific station is proposed in this paper.

  17. Otology at the Academy of Gondishapur 200-600 CE.

    Science.gov (United States)

    Ruben, Robert J

    2017-12-01

    To investigate the way in which otology was practiced at the Academy of Gondishapur in ancient Persia from 200 to 600 CE. The pertinent literature, using German and English translations of Latin, Greek, Arabic, and Sanskrit documents, was identified and reviewed through the indices of available books and through a PDF search for the following topics: auricle, deaf, deafness, dizziness, ear, hearing, medicine, otitis, pinna, punishment-ear, speech, surgery, vertigo, and voice. The medical school at the Academy of Gondishapur followed the medical and surgical practices of Greece and Rome and, in the 6th century, incorporated those from India as detailed in the Shutra Samhita. This shutra, which originated during the first millennium BCE, detailed many interventions, among which one of the most unusual was the use of a pedicle cheek flap to restore the pinnae. The use of the pedicle flap for pinna restoration appears not have been reported in literature again until 1931, by Jacque Joseph. During the period of late antiquity, medical knowledge of both the east and west was preserved and taught in Persia. Among surgical interventions used during the first millennium BCE in India, knowledge of which passed, through the shutra, to the Sasanian Empire in the 6th century CE, was use of the pedicle cheek flap for pinna reconstruction. Even as late as the Renaissance, the pedicle flap was not known to surgeons in the West, and a pedicle flap, though not a cheek flap, was first incorporated into Western medical practice during the 1930s.

  18. The Asia-RiCE activity with data cube

    Science.gov (United States)

    Oyoshi, K.; Sobue, S.; LE Toan, T.; Lam, N. D.

    2017-12-01

    The Asia-RiCE initiative (http://www.asia-rice.org) has been organized to enhance rice production estimates through the use of Earth observation satellites data, and seeks to ensure that Asian rice crops are appropriately represented within GEO Global Agriculture Monitoring (GEO-GLAM) to support FAO Agriculture Market Information System (FAO-AMIS). Asia-RiCE is composed of national teams that are actively contributing to the Crop Monitor for AMIS and developing technical demonstrations of rice crop monitoring activities using both Synthetic Aperture Radar (SAR) data (Radarsat-2 from 2013; Sentinel-1 and ALOS-2 from 2015.From 2016 after the successful rice crop area and growing estimation using SAR in a technical demonstration site (provincial level), wall-to-wall (national scale) excurse as phase 2 has been implemented in Vietnam and Indonesia in cooperation with ministry of agriculture and space agencies. This paper reports this year activity of 2017 accomplishment and way forward, especially for analysis ready data (ARD) definition of SAR to ingest to CEOS data cube to provide national scale service in Vietnam and Indonesia.

  19. La vérite sur ce qui nous motive

    CERN Document Server

    Pink, Daniel H

    2011-01-01

    Voici enfin la traduction française du best-seller international DRIVE ! Qu'est-ce qui nous motive vraiment ? Dans quels cas sommes-nous les plus performants et les plus enthousiastes ? La plupart d'entre nous sommes persuadés que les récompenses (salaire, primes...) sont notre meilleure motivation. La logique de la carotte et du bâton finalement... Et si nous faisions fausse route ? En s'appuyant sur quatre décennies d'études scientifiques et psychologiques sur la motivation humaine, Pink démontre que les entreprises dirigent très mal leurs équipes avec d'énormes conséquences sur notre vie (absence d'ambition, lassitude, morosité). Le secret de la performance (et de la satisfaction) dans les entreprises, l'enseignement ou dans notre vie personnelle , c'est le besoin profondément humain de diriger sa propre vie, d'apprendre, de créer de nouvelles choses et de s'améliorer. Dans ce livre, Pink examine les 3 éléments de la motivation, l'autonomie, la maîtrise et le besoin de donner un sens ...

  20. Ceļa servitūts

    OpenAIRE

    Livdāns, Dāvis

    2016-01-01

    Bakalaura darba tēma ir “Ceļa servitūts.” Bakalaura darba mērķis ir izpētīt ceļa servitūta nodibināšanas kārtību, iespējamās kļūdas, praksē nodibināto servitūtu problēmjautājumus un to risinājumus. Bakalaura darba tapšanas stadijā autors izmantoja zinātnisko literatūru, normatīvos aktus, kā arīi ar to tapšanu saistītos dokumentus un juridiskās prakses materiālus. Darbā ir apskatīti gan Civillikumā noteiktie servitūtu nodibināšanas pamati, gan citi iespējamie nodibināšanas pamati, pēc kā ir an...

  1. Irradiation effects in UO2 and CeO2

    International Nuclear Information System (INIS)

    Ye, Bei; Oaks, Aaron; Kirk, Mark; Yun, Di; Chen, Wei-Ying; Holtzman, Benjamin; Stubbins, James F.

    2013-01-01

    Single crystal CeO 2 , as a surrogate material to UO 2 , was irradiated with 500 keV xenon ions at 800 °C while being observed using in situ transmission electron microscopy (TEM). Experimental results show the formation and growth of defect clusters including dislocation loops and cavities as a function of increasing atomic displacement dose. At high dose, the dislocation loop structure evolves into an extended dislocation line structure, which appears to remain stable to the high dose levels examined in this study. A high concentration of cavities was also present in the microstructure. Despite high atomic displacement doses, the specimen remained crystalline to a cumulated dose of 5 × 10 15 ions/cm 2 , which is consistent with the known stability of the fluorite structure under high dose irradiation. Kinetic Monte Carlo calculations show that oxygen mobility is substantially higher in hypo-stoichiometric UO 2 /CeO 2 than hyper-stoichiometric systems. This result is consistent with the ability of irradiation damage to recover even at intermediate irradiation temperatures

  2. What was the population of Great Zimbabwe (CE1000 - 1800?

    Directory of Open Access Journals (Sweden)

    Shadreck Chirikure

    Full Text Available The World Heritage Site of Great Zimbabwe is one of the most iconic and largest archaeological settlements in Africa. It was the hub of direct and indirect trade which internally connected various areas of southern Africa, and externally linked them with East Africa and the Near and Far East. Archaeologists believe that at its peak, Great Zimbabwe had a fully urban population of 20,000 people concentrated in approximately 2.9 square kilometres (40 percent of 720 ha. This translates to a population density of 6,897, which is comparable with that of some of the most populous regions of the world in the 21st century. Here, we combine archaeological, ethnographic and historical evidence with ecological and statistical modelling to demonstrate that the total population estimate for the site's nearly 800-year occupational duration (CE1000-1800, after factoring in generational succession, is unlikely to have exceeded 10,000 people. This conclusion is strongly firmed up by the absence of megamiddens at the site, the chronological differences between several key areas of the settlement traditionally assumed to be coeval, and the historically documented low populations recorded for the sub-continent between CE1600 and 1950.

  3. Genome Mining in Sorangium cellulosum So ce56

    Science.gov (United States)

    Ewen, Kerstin Maria; Hannemann, Frank; Khatri, Yogan; Perlova, Olena; Kappl, Reinhard; Krug, Daniel; Hüttermann, Jürgen; Müller, Rolf; Bernhardt, Rita

    2009-01-01

    Myxobacteria, especially members of the genus Sorangium, are known for their biotechnological potential as producers of pharmaceutically valuable secondary metabolites. The biosynthesis of several of those myxobacterial compounds includes cytochrome P450 activity. Although class I cytochrome P450 enzymes occur wide-spread in bacteria and rely on ferredoxins and ferredoxin reductases as essential electron mediators, the study of these proteins is often neglected. Therefore, we decided to search in the Sorangium cellulosum So ce56 genome for putative interaction partners of cytochromes P450. In this work we report the investigation of eight myxobacterial ferredoxins and two ferredoxin reductases with respect to their activity in cytochrome P450 systems. Intriguingly, we found not only one, but two ferredoxins whose ability to sustain an endogenous So ce56 cytochrome P450 was demonstrated by CYP260A1-dependent conversion of nootkatone. Moreover, we could demonstrate that the two ferredoxins were able to receive electrons from both ferredoxin reductases. These findings indicate that S. cellulosum can alternate between different electron transport pathways to sustain cytochrome P450 activity. PMID:19696019

  4. Implantation sites of Ce and Gd in diamond

    CERN Document Server

    Bharuth-Ram, K; Hofsäss, H C; Ronning, C; Dietrich, M

    2002-01-01

    The implantation sites of rare earth (RE) probes /sup 141/Ce (t/sub 1 /2/=32 d) and /sup 149/Gd (t/sub 1/2/=9.28 d) in diamond have been investigated using the emission channeling (EC) technique. Parent isotopes /sup 141/Cs and /sup 149/Dy were implanted into type IIa, diamond samples at an energy of 60 keV at the online isotope separator ISOLDE at CERN. /sup 141/Cs decays through the chain /sup 141/Cs-/sup 141/Ba-/sup 141/La-/sup 141/Ce-/sup 141/ Pr. EC measurements were made on the 102 keV conversion electrons emitted in the decay of /sup 141/Pr to its ground state. The decay of /sup 149 /Dy follows the chain /sup 149/Dy-/sup 149/Tb-/sup 149/Gd-/sup 149 /Eu-/sup 149/Sm. EC measurements were made on the 101 keV electrons emitted in the decay of /sup 149/Eu. Two-dimensional channeling patterns of the conversion electrons were obtained along and axial directions by raster scans with a Si surface barrier detector. Comparison of the observed patterns with simulated spectra show that in diamond 45-50% of the RE...

  5. Particle-specific toxicity and bioavailability of cerium oxide (CeO{sub 2}) nanoparticles to Arabidopsis thaliana

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Xinping; Pan, Haopeng [College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095 (China); Wang, Peng, E-mail: p.wang3@uq.edu.au [College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095 (China); The University of Queensland, School of Agriculture and Food Sciences, St. Lucia, Queensland 4072 (Australia); Zhao, Fang-Jie [College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095 (China); Rothamsted Research, Harpenden, Hertfordshire AL5 2JQ (United Kingdom)

    2017-01-15

    Highlights: • The phytotoxicity and uptake of CeO{sub 2} NPs were examined in Arabidopsis. • CeO{sub 2} NPs stimulated plant growth at low doses but were toxic at high doses. • The toxicity was due to the NPs per se, rather than from the dissolved Ce ions. • A similar up-translocation factor was found for CeO{sub 2} NPs, bulk CeO{sub 2} and Ce ions. - Abstract: The use of manufactured cerium oxide nanoparticles (CeO{sub 2}-NPs) in consumer products has increased markedly over the past decade, and their release into natural ecosystems is unavoidable. This study investigated the phytotoxicity and uptake of CeO{sub 2}-NPs in Arabidopsis thaliana grown in an agar medium. Although low concentrations of CeO{sub 2}-NPs had stimulatory effects on plant growth, at higher concentrations, CeO{sub 2}-NPs reduced growth and had adverse effects on the antioxidant systems and photosystem. Importantly, the toxicity resulted from the nanoparticles per se, rather than from the dissolved Ce ions. CeO{sub 2}-NPs were taken up and subsequently translocated to shoot tissues, and transmission electron microscopy (TEM) showed the presence of a large number of needle-like particle aggregations in the intercellular regions and the cytoplasm of leaf cells. The up-translocation factor to shoots was independent of the concentrations of Ce in the roots and the supplied forms of Ce (i.e. CeO{sub 2}-NPs, CeO{sub 2}-bulk, and ionic Ce), suggesting that endocytosis is likely to be a general mechanism responsible for the translocation of these Ce compounds. These findings provide important information regarding the toxicity and uptake of CeO{sub 2}-NPs in plants, which needs to be considered in environmental risk assessment for the safe use and disposal of CeO{sub 2}-NPs.

  6. Excitation light source dependence of emission in Sn2+-Ce3+ codoped ZnO-P2O5 glasses

    OpenAIRE

    Masai, Hirokazu; Hino, Yusuke; Yanagida, Takayuki; Fujimoto, Yutaka; Fukuda, Kentaro; Yoko, Toshinobu

    2013-01-01

    Correlation between excitation light source and the emission property of Sn^{2+}-Ce^{3+} co-doped zinc phosphate glasses is examined. Although photoluminescence (PL) peaks of both Sn^{2+}and Ce^{3+} shifted with increasing amount of Ce^{3+}, there was little energy resonance between Sn^{2+} and Ce^{3+} emission centers. On the other hand, radioluminescence (RL) spectra excited by X-ray was independent of the Ce concentration, indicating that emission was mainly observed from Sn^{2+} emission ...

  7. Room-temperature synthesis and characterization of porous CeO{sub 2} thin films

    Energy Technology Data Exchange (ETDEWEB)

    Chu, Dewei; Masuda, Yoshitake; Ohji, Tatsuki; Kato, Kazumi [National Institute of Advanced Industrial Science and Technology (AIST), Anagahora, Shimoshidami, Moriyama-ku, Nagoya (Japan)

    2012-01-15

    CeO{sub 2} thin films with hexagonal-shaped pores were successfully prepared by a facile electrodeposition at room temperature combined with an etching process. By using electrodeposited ZnO nanorods as a soft template, the morphology, and microstructure of the CeO{sub 2} could be controlled. TEM observation indicated that as-prepared CeO{sub 2} film is composed of nanocrystals with average size of several nanometers, while XPS analysis showed the coexistence of Ce{sup 3+} and Ce{sup 4+} in the film. The photoluminescence properties of CeO{sub 2} films were measured, which showed much higher sensitivity compared to bare substrate. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  8. Room-temperature synthesis and characterization of porous CeO2 thin films

    International Nuclear Information System (INIS)

    Chu, Dewei; Masuda, Yoshitake; Ohji, Tatsuki; Kato, Kazumi

    2012-01-01

    CeO 2 thin films with hexagonal-shaped pores were successfully prepared by a facile electrodeposition at room temperature combined with an etching process. By using electrodeposited ZnO nanorods as a soft template, the morphology, and microstructure of the CeO 2 could be controlled. TEM observation indicated that as-prepared CeO 2 film is composed of nanocrystals with average size of several nanometers, while XPS analysis showed the coexistence of Ce 3+ and Ce 4+ in the film. The photoluminescence properties of CeO 2 films were measured, which showed much higher sensitivity compared to bare substrate. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  9. Volta potential of clad AA2024 aluminium after exposure to CeCl3 solution

    International Nuclear Information System (INIS)

    Andreatta, F.; Druart, M.-E.; Marin, E.; Cossement, D.; Olivier, M.-G.; Fedrizzi, L.

    2014-01-01

    Highlights: • Alkaline etch of clad AA2024 enhances precipitation of Ce compounds. • Exposure to CeCl 3 solution decreases Volta potential of alkaline etched substrate. • Ce compounds reduce the driving force for initiation of localized attack. - Abstract: AA2024 clad with AA1050 was immersed in CeCl 3 solution to promote deposition of cerium species. The deposition occurs on the entire sample surface for the alkaline etched substrate, while it is very limited for the degreased substrate. The surface potential (Volta potential) was investigated by scanning Kelvin probe force microscopy after different immersion times in CeCl 3 solution. The preferential deposition of Ce compounds at Al–Fe intermetallic sites progressively reduces their Volta potential difference relative to the matrix in the alkaline etched substrate. This reduces the susceptibility to localized attack of the intermetallics as proven by potentiodynamic polarization measurements

  10. The isolation of 139Ce after production by a proton-induced nuclear reaction on praseodymium

    International Nuclear Information System (INIS)

    Van der Walt, T.N.; Vermeulen, C.

    2004-01-01

    A method, based on anion exchange chromatography, is presented for the isolation of 139 Ce after production by a proton-induced nuclear reaction on a thick praseodymium target. After bombardment the target is dissolved in nitric acid and 139 Ce oxidised to the Ce(IV) oxidation state with bromic acid. 139 Ce is then separated form the praseodymium by anion exchange chromatography on a Ag MP-1 resin column in a nitric acid - bromic acid mixture. 139 Ce is sorbed onto the resin column and praseodymium eluted with the acid mixture. The bromic acid is washed out of the column with nitric acid and 139 Ce finally eluted with dilute nitric acid containing sulphur dioxide

  11. Ce activated potassium bromide phosphor for lyoluminescence dosimetry of ionizing radiation

    International Nuclear Information System (INIS)

    Bhujbal, P.M.; Dhoble, S.J.

    2013-01-01

    The lyoluminescence (LL) properties of gamma irradiated KBr:Ce phosphor are reported in this paper. The samples were prepared by wet chemical route. The prepared material was characterized by lyoluminescence technique. LL in KBr:Ce have been recorded for different gamma doses. The nature of variation of peak LL intensity is found to be sublinear with gamma irradiation dose, and the peak LL intensity is found to be dependent on concentrations of added Ce in the samples. Negligible fading in the prepared KBr:Ce (0.5 mol%) sample is observed. -- Highlights: • The LL intensities are found to be dependent on concentrations of Ce ion. • The LL intensities are found to be dependent on gamma rays radiation dose. • Dose response of KBr:Ce (0.5 mol%) is observed linear between 0.08 and 1.00 kGy. • The prepared material may be useful for ionizing radiation dosimetry

  12. GAGG:ce single crystalline films: New perspective scintillators for electron detection in SEM

    International Nuclear Information System (INIS)

    Bok, Jan; Lalinský, Ondřej; Hanuš, Martin; Onderišinová, Zuzana; Kelar, Jakub; Kučera, Miroslav

    2016-01-01

    Single crystal scintillators are frequently used for electron detection in scanning electron microscopy (SEM). We report gadolinium aluminum gallium garnet (GAGG:Ce) single crystalline films as a new perspective scintillators for the SEM. For the first time, the epitaxial garnet films were used in a practical application: the GAGG:Ce scintillator was incorporated into a SEM scintillation electron detector and it showed improved image quality. In order to prove the GAGG:Ce quality accurately, the scintillation properties were examined using electron beam excitation and compared with frequently used scintillators in the SEM. The results demonstrate excellent emission efficiency of the GAGG:Ce single crystalline films together with their very fast scintillation decay useful for demanding SEM applications. - Highlights: • First practical application of epitaxial garnet films demonstrated in SEM. • Improved image quality of SEM equipped with GAGG:Ce single crystalline thin film scintillator. • Scintillation properties of GAGG:Ce films compared with standard bulk crystal scintillators.

  13. Luminescence properties of LiPrxCe1-xP4O12

    International Nuclear Information System (INIS)

    Shalapska, T.; Stryganyuka, G.; Trotsc, D.; Demkiv, T.; Gektin, A.; Voloshinovskii, A.; Dorenbos, P.

    2010-01-01

    LiPr 1-x Ce x P 4 O 12 (x=0, 0.002, 0.02; 0.1) powder samples were prepared using the melt solution technique. Luminescent parameters of LiPr 1-x Ce x P 4 O 12 phosphors have been investigated under ultraviolet-vacuum ultraviolet (3-12 eV) synchrotron radiation and X-rays excitation at room and near liquid He temperatures. Excitation luminescence spectra of Ce 3+ emission, luminescent spectra and decay curves from the lower excited state levels of the 4f 1 5d 1 and 5d 1 electronic configuration of the Pr 3+ and Ce 3+ , respectively, clearly indicate energy transfer from Pr 3+ to Ce 3+ . Energy migration proceeds via the Pr-sublattice followed by nonradiation transfer from Pr 3+ to Ce 3+ ions.

  14. Luminescence and scintillation properties of LuPO4-Ce nanoparticles

    International Nuclear Information System (INIS)

    Vistovskyy, V.; Malyy, T.; Pushak, A.; Vas’kiv, A.; Shapoval, A.; Mitina, N.; Gektin, A.; Zaichenko, A.; Voloshinovskii, A.

    2014-01-01

    Study of the spectral-luminescence parameters of LuPO 4 -Ce nanoparticles upon the excitation by X-ray quanta and synchrotron radiation with photon energies of 4–25 eV was performed. Nanoparticles with mean size about a=35 nm and nanoparticles with size less than 12 nm reveal the different structures of cerium centers. Luminescence efficiency of LuPO 4 -Ce nanoparticles of a 4 -Ce nanoparticles studied using synchrotron and X-ray excitation. • Different structure of Ce 3+ -centers has been revealed for LuPO 4 -Ce nanoparticles. • Luminescence of LuPO 4 -Ce with size less than 12 nm is strongly quenched upon the X-ray excitation

  15. Comparison of Efficiencies and Mechanisms of Catalytic Ozonation of Recalcitrant Petroleum Refinery Wastewater by Ce, Mg, and Ce-Mg Oxides Loaded Al2O3

    Directory of Open Access Journals (Sweden)

    Chunmao Chen

    2017-02-01

    Full Text Available The use of catalytic ozonation processes (COPs for the advanced treatment of recalcitrant petroleum refinery wastewater (RPRW is rapidly expanding. In this study, magnesium (Mg, cerium (Ce, and Mg-Ce oxide-loaded alumina (Al2O3 were developed as cost efficient catalysts for ozonation treatment of RPRW, having performance metrics that meet new discharge standards. Interactions between the metal oxides and the Al2O3 support influence the catalytic properties, as well as the efficiency and mechanism. Mg-Ce/Al2O3 (Mg-Ce/Al2O3-COP reduced the chemical oxygen demand by 4.7%, 4.1%, 6.0%, and 17.5% relative to Mg/Al2O3-COP, Ce/Al2O3-COP, Al2O3-COP, and single ozonation, respectively. The loaded composite metal oxides significantly increased the hydroxyl radical-mediated oxidation. Surface hydroxyl groups (–OHs are the dominant catalytic active sites on Al2O3. These active surface –OHs along with the deposited metal oxides (Mg2+ and/or Ce4+ increased the catalytic activity. The Mg-Ce/Al2O3 catalyst can be economically produced, has high efficiency, and is stable under acidic and alkaline conditions.

  16. Laser clad Ni-base alloy added nano- and micron-size CeO 2 composites

    Science.gov (United States)

    Zhang, Shi Hong; Li, Ming Xi; Cho, Tong Yul; Yoon, Jae Hong; Lee, Chan Gyu; He, Yi Zhu

    2008-07-01

    Micron-size Ni-base alloy (NBA) powders are mixed with both 1.5 wt% (%) micron-CeO 2 (m-CeO 2) and also 1.0-3.0% nano-CeO 2 (n-CeO 2) powders. These mixtures are coated on low carbon steel (Q235) by 2.0 kW CO 2 laser cladding. The effects on microstructures, microhardness and wear resistance of the coating by the addition of m- and n-CeO 2 powders to NBA (m- and n-CeO 2/NBA) have been investigated. Addition to the primary phases of γ-Ni, Cr 23C 6 and Ni 3B of NBA coating, CeNi 3 shows up both in m- and n-CeO 2/NBA coatings and CeNi 5 appears only in n-CeO 2/NBA coating. Directional dendrite and coarse equiaxed dendrite are grown in m-CeO 2/NBA coating from interface to central zone, whereas multi-oriented dendrite and fine equiaxed dendrite growth by addition of n-CeO 2. The microhardness and wear resistance of coatings are greatly improved by CeO 2 powder addition, and compared to the addition of 1.0% and 3.0%, 1.5% n-CeO 2/NBA is the best. Hardness and wear resistance of the coating improves with decreasing CeO 2 size from micron to nano.

  17. Spray deposited CeO2–TiO2 counter electrode for electrochromic ...

    Indian Academy of Sciences (India)

    Abstract. Optically passive thin films of CeO2–TiO2 mixed oxides with molar ratio of Ce/Ti of 0.05 were deposited by the spray pyrolysis technique (SPT) on a glass and fluorine-doped tin oxide (FTO)-coated glass substrates. Precur- sor solution containing cerium nitrate hexahydrate (Ce(NO3)2·6H2O) and titanium ...

  18. Update History of This Database - tRNADB-CE | LSDB Archive [Life Science Database Archive metadata

    Lifescience Database Archive (English)

    Full Text Available switchLanguage; BLAST Search Image Search Home About Archive Update History Data List Contact us tRNAD...11/08/25 License is updated. 2010/03/29 tRNADB-CE English archive site is opened. 2008/7/1 tRNADB-CE( http:/...Download License Update History of This Database Site Policy | Contact Us Update History of This Database - tRNADB-CE | LSDB Archive ...

  19. Luminescence of Ce3+ doped LaPO4 nanophosphors upon Ce3+ 4f-5d and band-to-band excitation

    International Nuclear Information System (INIS)

    Stryganyuk, G.; Trots, D.M.; Voloshinovskii, A.; Shalapska, T.; Zakordonskiy, V.; Vistovskyy, V.; Pidzyrailo, M.; Zimmerer, G.

    2008-01-01

    Luminescence spectral-kinetic studies have been performed for pure and Ce-doped LaPO 4 micro- and nanosized phosphates using synchrotron radiation for the excitation within 5-20 eV energy range at T=8-300 K. Mechanisms for the excitation of Ce 3+ 5d-4f emission as well as the quenching processes are discussed. The influence of surface defects has been considered to modify considerably the luminescent properties of nanosized phosphors upon the excitation in the energy range of Ce 3+ 4f-5d transitions and LaPO 4 host absorption

  20. Ce doped NiO nanoparticles as selective NO2 gas sensor

    Science.gov (United States)

    Gawali, Swati R.; Patil, Vithoba L.; Deonikar, Virendrakumar G.; Patil, Santosh S.; Patil, Deepak R.; Patil, Pramod S.; Pant, Jayashree

    2018-03-01

    Metal oxide gas sensors are promising portable gas detection devices because of their advantages such as low cost, easy production and compact size. The performance of such sensors is strongly dependent on material properties such as morphology, structure and doping. In the present study, we report the effect of cerium (Ce) doping on nickel oxide (NiO) nano-structured thin film sensors towards various gases. Bare NiO and Ce doped NiO nanoparticles (Ce:NiO) were synthesized by sol-gel method. To understand the effect of Ce doping in nickel oxide, various molar percentages of Ce with respect to nickel were incorporated. The structure, phase, morphology and band-gap energy of as-synthesized nanoparticles were studied by XRD, SEM, EDAX and UV-vis spectroscopy. Thin film gas sensors of all the samples were prepared and subjected to various gases such as LPG, NH3, CH3COCH3 and NO2. A systematic and comparative study reveals an enhanced gas sensing performance of Ce:NiO sensors towards NO2 gas. The maximum sensitivity for NO2 gas is around 0.719% per ppm at moderate operating temperature of 150 °C for 0.5% Ce:NiO thin film gas sensor. The enhanced gas sensing performance for Ce:NiO is attributed to the distortion of crystal lattice caused by doping of Ce into NiO.

  1. Investigating the large degeneracy Kondo lattice metamagnet CeTiGe: Crystal growth and doping studies

    Energy Technology Data Exchange (ETDEWEB)

    Gruner, T.; Caroca-Canales, N.; Deppe, M.; Geibel, C. [MPI fuer Chemische Physik fester Stoffe, 01187, Dresden (Germany); Sereni, J. [Centro Atomico Bariloche, 8400, S. C. de Bariloche (Argentina)

    2011-07-01

    CeTiGe is a paramagnetic Kondo lattice system with a large orbital degeneracy involved in the formation of the heavy Fermion ground state. Recently we discovered that this compound presents a huge metamagnetic transition at B{sub MMT} {approx} 13 T, with much larger anomalies in magnetization, magnetoresistance and magnetostriction than in the archetypical Kondo lattice metamagnet CeRu{sub 2}Si{sub 2}. Since CeTiGe forms in a pronounced peritectic reaction the growth of single crystals is difficult. We therefore studied the Ce-Ti-Ge ternary metallographic phase diagram to get a sound basis for future crystal growth attempts. Preliminary results of growth experiments based on these studies are promising and shall be discussed. Furthermore, Ti-rich CeTiGe was recently reported to present a high temperature phase crystallizing in the closely related CeScSi structure type. In order to study this structural instability and the effect on the physical properties, we studied the effect of substituting Sc for Ti, since pure CeScGe crystallizes in the CeScSi structure type. In well annealed samples we observed a two phase region in the range 10% - 25%-Sc-substitution. Preliminary investigations of the CeSc{sub x}Ti{sub 1-x}Ge alloy suggest it is a promising candidate for the observation of a ferromagnetic quantum critical point in a large degeneracy Kondo lattice system.

  2. Metallic oxides supported in CeO{sub 2} and CeO{sub 2}-La{sub 2} O{sub 3} for low temperature shift reaction; Oxidos metalicos suportados em CeO{sub 2} e CeO{sub 2}-La{sub 2} O{sub 3} para reacao shift a baixa temperatura

    Energy Technology Data Exchange (ETDEWEB)

    Maluf, Silvia Salua; Assaf, Elisabete Moreira [Universidade de Sao Paulo (USP), Sao Carlos, SP (Brazil). Inst. de Quimica]. E-mail: sil_maluf@iqsc.usp.br

    2008-07-01

    This work studied copper and zinc oxides supported in CeO{sub 2} and CeO{sub 2}/La{sub 2}O{sub 3}. The catalytic tests for low temperature shift reaction, carried out for samples, showed the Cu-Ce catalyst presents the highest value of CO conversion (50%) and after the Cu-Ce-La catalysts (30%). The other catalysts showed CO conversion in range of 15%. This behavior is related with surface area, and also with the amount of Cu in the surface of samples (author)

  3. Highly porous CeO2 nanostructures prepared via combustion synthesis for supercapacitor applications

    DEFF Research Database (Denmark)

    Kadirvelayutham, Prasanna; Santhoshkumar, P.; Jo, Yong Nam

    2017-01-01

    We report highly porous CeO2 nanostructures (CeO2 NSs) suitable for supercapacitor applications, synthesized using a fast and cost effective combustion approach. Due to its prominent valence states of Ce3+/Ce4+, CeO2 has emerged as a promising pseudocapacitive material. The drawback of using CeO2...... as a supercapacitor electrode is its poor electrical conductivity. We overcame this drawback of CeO2 by creating oxygen vacancies on its surface, which act to enhance its electrical conductivity. The physical interpretation of the as-synthesized CeO2 NSs shows that they have dense active sites and diffusion pathways...... that enhance the performance of the electrode in a supercapacitor. Electrodes prepared using the synthesized CeO2 NSs exhibited the initial specific capacitance of 134.6 F g-1 and superior cycling stability of 92.5% after 1000 cycles at a constant current density of 1 A g-1, indicating their potential...

  4. Effect of Ce addition on the mechanical and electrochemical properties of a lithium battery shell alloy

    International Nuclear Information System (INIS)

    Zhang, Junchao; Ding, Dongyan; Xu, Xinglong; Gao, Yongjin; Chen, Guozhen; Chen, Weigao; You, Xiaohua; Huang, Yuanwei; Tang, Jinsong

    2014-01-01

    Highlights: • Fabrication of Ce-free and Ce-containing Al–Cu–Mn–Fe–Mg alloy. • TEM, tensile and electrochemical characterization of the alloys. • Ce element greatly affects the precipitation of the alloy. • Ce element had great impact on the tensile strength and corrosion potential of the alloys. - Abstract: Due to severe application environment lithium battery shell of new-energy automotives requires increasing demands for using high performance aluminum alloys. In the present work, effect of Ce addition on the microstructure, tensile and electrochemical properties of an Al–Cu–Mn–Mg–Fe alloy were investigated through using X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), tensile tests and electrochemical tests. The experimental results indicated that the addition of Ce element could promote the precipitation of second phases. With addition of 0.36% Ce, high melting point Al 8 Cu 4 Ce phase and many Al 20 Cu 2 Mn 3 particles could be found. In addition, the precipitation of conventionally dominant phase of Al 2 Cu could be suppressed in alloy. The Ce addition was found to result in enhanced tensile strength and improved corrosion resistance

  5. Kinetics of a redox reaction in the system Ce(IV) β-diketonate - additional ligand

    International Nuclear Information System (INIS)

    Anufrieva, S.I.; Snezhko, N.I.; Pechurova, N.I.; Martynenko, L.N.; Spitsyn, V.I.

    1982-01-01

    Preparation of solutions containing stable compounds of Ce(IV) with organic ligands is difficult, because even strong Ce(IV) complexes undergo intramolecular reduction and have a tendency to hydrolysis. It is known that Ce(IV) β-diketonates have different resistances to reduction inorganic solvents, depending on the structure. Using spectrophotometric analysis we have investigated the oxidation-reduction characteristics of solutions of certain Ce(IV) β-diketonates in benzene in the absence and presence of neutral ligands containing donor O or N atoms

  6. Database Description - tRNADB-CE | LSDB Archive [Life Science Database Archive metadata

    Lifescience Database Archive (English)

    Full Text Available switchLanguage; BLAST Search Image Search Home About Archive Update History Data List Contact us tRNAD...B-CE Database Description General information of database Database name tRNADB-CE Alter...CC BY-SA Detail Background and funding Name: MEXT Integrated Database Project Reference(s) Article title: tRNAD... 2009 Jan;37(Database issue):D163-8. External Links: Article title: tRNADB-CE 2011: tRNA gene database curat...n Download License Update History of This Database Site Policy | Contact Us Database Description - tRNADB-CE | LSDB Archive ...

  7. Effect of Ce addition on the mechanical and electrochemical properties of a lithium battery shell alloy

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Junchao [School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240 (China); Ding, Dongyan, E-mail: dyding@sjtu.edu.cn [School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240 (China); Xu, Xinglong [School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240 (China); Gao, Yongjin; Chen, Guozhen; Chen, Weigao; You, Xiaohua [Huafon NLM Al Co., Ltd, Shanghai 201506 (China); Huang, Yuanwei; Tang, Jinsong [Shanghai Huafon Materials Technology Institute, Shanghai 201203 (China)

    2014-12-25

    Highlights: • Fabrication of Ce-free and Ce-containing Al–Cu–Mn–Fe–Mg alloy. • TEM, tensile and electrochemical characterization of the alloys. • Ce element greatly affects the precipitation of the alloy. • Ce element had great impact on the tensile strength and corrosion potential of the alloys. - Abstract: Due to severe application environment lithium battery shell of new-energy automotives requires increasing demands for using high performance aluminum alloys. In the present work, effect of Ce addition on the microstructure, tensile and electrochemical properties of an Al–Cu–Mn–Mg–Fe alloy were investigated through using X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), tensile tests and electrochemical tests. The experimental results indicated that the addition of Ce element could promote the precipitation of second phases. With addition of 0.36% Ce, high melting point Al{sub 8}Cu{sub 4}Ce phase and many Al{sub 20}Cu{sub 2}Mn{sub 3} particles could be found. In addition, the precipitation of conventionally dominant phase of Al{sub 2}Cu could be suppressed in alloy. The Ce addition was found to result in enhanced tensile strength and improved corrosion resistance.

  8. Experimental investigation and thermodynamic calculation of the Zn–Fe–Ce system

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Longfei; Wu, Changjun [Jiangsu Key Laboratory of Materials Surface Science and Technology, Changzhou University, Jiangsu 213164 (China); Jiangsu Collaborative Innovation Center of Photovolatic Science and Engineering, Changzhou University, Jiangsu 213164 (China); Wang, Jianhua, E-mail: wangjh@cczu.edu.cn [Jiangsu Key Laboratory of Materials Surface Science and Technology, Changzhou University, Jiangsu 213164 (China); Jiangsu Collaborative Innovation Center of Photovolatic Science and Engineering, Changzhou University, Jiangsu 213164 (China); Liu, Ya; Tu, Hao; Su, Xuping [Jiangsu Key Laboratory of Materials Surface Science and Technology, Changzhou University, Jiangsu 213164 (China); Jiangsu Collaborative Innovation Center of Photovolatic Science and Engineering, Changzhou University, Jiangsu 213164 (China)

    2015-11-05

    The 450 °C and 600 °C isothermal sections of the Zn–Fe–Ce system were investigated using equilibrated alloys and diffusion couples. The samples were analyzed by Scanning Electron Microscopy equipped with Energy Dispersive X-ray Spectrometer analysis and X-ray power diffraction. 15 and 13 three-phase regions were identified to exist at 450 °C and 600 °C, respectively. No ternary compound was found. Ce can not dissolve into all the Zn–Fe binary compounds and the solubilities of Fe in all the Zn–Ce binary phases were limited. All the Zn–Fe compounds can equilibrate with CeZn{sub 11} and all the Ce–Zn compounds (except CeZn) can equilibrate with α-Fe. Furthermore, thermodynamic extrapolation of the Zn–Fe–Ce system was carried out and showed good agreement well with detected phase relationships. - Highlights: • 450 °C and 600 °C sections of the Zn–Fe–Ce system were constructed. • No ternary compound exists. • Ce can not dissolve into all the Zn–Fe compounds. • All the Fe–Zn compounds can equilibrate with CeZn{sub 11}. • Thermodynamic extrapolation results agree with experimental data.

  9. Investigation of the 600 C isothermal section of the Fe-Al-Ce ternary system

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, Huiyun; Yin, Fucheng [Xiangtan Univ., Hunan (China). School of Materials Science and Engineering; Xiangtan Univ., Hunan (China). Key Laboratory of Materials Design and Preparation Technology of Hunan Province; Li, Zhi [Xiangtan Univ., Hunan (China). School of Materials Science and Engineering; Xiangtan Univ., Hunan (China). Key Laboratory of Materials Design and Preparation Technology of Hunan Province; Xiangtan Univ., Hunan (China). Key Laboratory of Key Film Materials and Application for Equipment (Hunan province); Ji, Li [South China University of Technology, Guangdong (China). School of Materials Science and Engineering

    2017-01-15

    The isothermal section of the Fe-Al-Ce system at 600 C was determined by means of scanning electron microscopy coupled with energy dispersive spectroscopy and X-ray powder diffraction. Twenty three-phase regions were confirmed experimentally, and two three-phase regions could be deduced in this section. Five ternary compounds, i. e., τ{sub 1}, τ{sub 2}, τ{sub 3}, τ{sub 5}, and τ{sub 6}, exist at 600 C. The Fe{sub 2}Ce phase contains 6.6 at.% Al in the Fe-Al-Ce system. The Fe solubility in α-Al, αAl{sub 11}Ce{sub 3}, αAl{sub 3}Ce, Al{sub 2}Ce, AlCe, and AlCe{sub 3} is approximately 1.7 at.%, 1.1 at.%, 1.2 at.%, 1.3 at.%, 5.8 at.%, and 0.1 at.%, respectively, and the solubility of Ce in α-Al, FeAl{sub 3}, Fe{sub 2}Al{sub 5}, FeAl{sub 2}, and FeAl is approximately 0.1 at.%, 1.2 at.%, 1.9 at.%, 0.9 at.%, and 3.7 at.%, respectively.

  10. Optical spectroscopy of Ce{sup 3+} in BaLiF{sub 3}

    Energy Technology Data Exchange (ETDEWEB)

    Yamaga, M.; Imai, T. [Department of Electrical and Electronic Engineering, Faculty of Engineering, Gifu University, Gifu 501-1193 (Japan); Shimamura, K.; Fukuda, T. [Institute for Materials Research, Tohoku University, Sendai 980-8577 (Japan); Honda, M. [Faculty of Science, Naruto University of Education, Naruto 772-8502 (Japan)

    2000-04-10

    The optical absorption spectrum of Ce{sup 3+} in BaLiF{sub 3} crystals consists of several overlapping broad bands. The Ce{sup 3+} luminescence shows broad bands due to moderate electron-phonon interaction in the 5d excited state. Three distinct Ce{sup 3+} sites in the crystal were assigned from the optical spectra. The luminescence spectrum from the dominant Ce{sup 3+} site has a large Stokes shift ({approx}8300 cm{sup -1}), whereas that from one of the two minor Ce{sup 3+} sites has a Stokes shift of half that magnitude ({approx}4400 cm{sup -1}), assuming that the excitation spectrum is almost the same as for the dominant site. The peaks of the lowest-energy absorption and luminescence bands for the other minor Ce{sup 3+} site are shifted to lower energy, and the Stokes shift energy ({approx}7800 cm{sup -1}) is close to that for the dominant site. These three Ce{sup 3+} sites are assigned to configurations of Ce{sup 3+} accompanied by different charge compensators. This assignment is consistent with preliminary electron spin-resonance results indicating that there exist two tetragonal and two orthorhombic Ce{sup 3+} centres in the absence of the cubic centre. (author)

  11. Single-crystal FCC and DHCP phases in Ce/Pr superlattices

    International Nuclear Information System (INIS)

    Lee, S.; Goff, J.P.; Ward, R.C.C.; Wells, M.R.; McIntyre, G.J.

    2002-01-01

    Cerium usually comprises a mixture of polycrystalline FCC and DHCP allotropes. Single-crystal Ce has been stabilised in Ce/Pr superlattices grown using molecular beam epitaxy. It is found that FCC or DHCP phases can be obtained depending on superlattice composition and growth conditions. Low-temperature neutron scattering was performed on Ce/Pr samples using the triple-axis spectrometer D10 at the ILL. Such measurements revealed one sample, [Ce 20 Pr 20 ] 60 , to be a single crystal with a DHCP unit cell; while another, [Ce 30 Pr 10 ] 56 , was a mixture of FCC and DHCP phases. Antiferromagnetic ordering of magnetic moments was observed in the DHCP sample (T N =11.1 K) with a magnetic structure similar to that found in bulk β-Ce. Surprisingly, the magnetic ordering was found to be confined to single Ce blocks. Furthermore, it was found that, at low temperatures, the lattice contraction observed for bulk FCC Ce was suppressed in Ce/Pr superlattices. (orig.)

  12. Complex impedance study on nano-CeO2 coating TiO2

    International Nuclear Information System (INIS)

    Zhang Mei; Wang Honglian; Wang Xidong; Li Wenchao

    2006-01-01

    Titanium dioxide (TiO 2 ) nanoparticles and cerium dioxide (CeO 2 ) nanoparticles coated titanium dioxide (TiO 2 ) nanoparticles (CeO 2 -TiO 2 nanoparticles) have been successfully synthesized by sol-gel method. The complex impedance of the materials was investigated. The grain resistance, boundary resistance and activation energy of the nanoparticles were calculated according to Arrhenius equation. According to calculating results, the active capacity of pure TiO 2 nanoparticles has been improved because of nano-CeO 2 coating. An optimal CeO 2 content of 4.9 mol% was achieved. The high resolution electron microscopy images of CeO 2 -TiO 2 nanoparticles showed that TiO 2 nanoparticles, as a core, were covered by CeO 2 nanoparticles. The average size of CeO 2 coating TiO 2 nanoparticles was about 70 nm. Scanning electron microscopy observation indicted that CeO 2 nanoparticle coating improved the separation, insulation, and stability the CeO 2 -TiO 2 nanoparticles, which was benefit to the activity of materials

  13. Effects of Ce, La and Ba addition on the electrochemical behavior of super duplex stainless steels

    International Nuclear Information System (INIS)

    Yoo, Yun-Ha; Choi, Yoon-Seok; Kim, Jung-Gu; Park, Yong-Soo

    2010-01-01

    The effects of rare earth metal (REM: Ce, La) and Ba addition on aqueous corrosion properties of super duplex stainless steels (SDSS) were investigated by electrochemical tests and surface analyses. The results of potentiodynamic test indicated that the passive range increased by the addition of Ce, La, and Ba, indicating increased relative resistance to localized corrosion. The EIS measurements showed that the Ce-La-Ba-bearing alloys exhibited higher R ct and R p values than the Ce-La-Ba-free alloy at the passive and breakdown states. Furthermore, the additions of REMs and Ba together promoted the formation of dense chromium-enriched passive film.

  14. Thermopower studies of doped CeAl sub 2 and UAl sub 2

    CERN Document Server

    Park, J G

    1997-01-01

    We have studied the thermopower of U doped CeAl sub 2 and Ce and La doped UAl sub 2. Despite different ground state properties of CeAl sub 2 and UAl sub 2 , the former being an antiferromagnetic heavy-fermion compound and the latter non-magnetic, we have found that not only thermopower data for pure CeAl sub 2 and UAl sub 2 are similar but also the thermopower results of doped samples behave similarly. Although the similarity seen in pure systems is yet to be understood, we interpret the doping effects as the results of changes in energy dependent relaxation time with doping. (author)

  15. Ternary ceramic alloys of Zr-Ce-Hf oxides

    Science.gov (United States)

    Becher, P.F.; Funkenbusch, E.F.

    1990-11-20

    A ternary ceramic alloy is described which produces toughening of zirconia and zirconia composites through the stress transformation from tetragonal phase to monoclinic phase. This alloy, having the general formula Ce[sub x]Hf[sub y]Zr[sub 1[minus]x[minus]y]O[sub 2], is produced through the addition of appropriate amounts of ceria and hafnia to the zirconia. Typically, improved toughness is achieved with about 5 to about 15 mol % ceria and up to about 40 mol % hafnia. The preparation of alloys of these compositions are given together with data as to the densities, tetragonal phase content, hardness and fracture toughness. The alloys are useful in preparing zirconia bodies as well as reinforcing ceramic composites. 1 fig.

  16. Pressure-induced magnetic transition in CeP

    International Nuclear Information System (INIS)

    Naka, T.; Matsumoto, T.; Mori, N.; Okayama, Y.; Haga, Y.; Suzuki, T.

    1997-01-01

    Pressure dependence of magnetization in CeP is investigated up to 2 GPa. Multi-step transitions are induced by pressure. An antiferromagnetic transition at T N =11 K below 0.1 GPa develops into two (magnetic) transitions at T L and T H in the region of 0.1 L , T H and T d above 1.3 GPa. For decreasing temperature an abrupt increase of magnetization, M(T), has been observed below T H and a round maximum of magnetization appears at T L for P≥0.4 GPa. Above 1.3 GPa, an anomalous decrease of M(T) begins at T d =10 K. Using previously reported 31 P-NMR shift data it is shown that the pressure dependence of a characteristic temperature, which is proportional to the crystal field splitting in the paramagnetic temperature region, decreases rapidly with increasing pressure. (orig.)

  17. Charge fluctuation in Ce-based filled-skutterudite

    International Nuclear Information System (INIS)

    Yogi, M; Niki, H; Mukuda, H; Kitaoka, Y; Sugawara, H; Sato, H

    2009-01-01

    We carried out 121,123 Sb nuclear quadrupole resonance (NQR) measurement on CeOs 4 Sb 12 to investigate an anomaly observed in ReOs 4 Sb 12 . The full width of half maximum of the NQR spectrum shows a step-like increase at 115 K with decreasing temperature (T). The nuclear spin-spin relaxation rate 1/T 2 also shows a divergence at the same T. These results are considered to be caused by a distribution of the electric field gradient (EFG) and its fluctuation, which might arise from a small deformation of the cage which consists of twelve Sb. It is considered that the anomaly observed in ReOs 4 Sb 12 at T ∼ 120 K is originated from an unique crystal structure of the filled skutterudite.

  18. Table incremental slow injection CE-CT in lung cancer

    International Nuclear Information System (INIS)

    Yoshida, Shoji; Maeda, Tomoho; Morita, Masaru

    1988-01-01

    The purpose of this study is to evaluate tumor enhancement in lung cancer under the table incremental study with slow injection of contrast media. The early serial 8 sliced images during the slow injection (1.5 ml/sec) of contrant media were obtained. Following the early images, delayed 8 same sliced images were taken in 2 minutes later. Chacteristic enhanced patterns of the primary cancer and metastatic mediastinal lymphnode were recognized in this study. Enhancement of the primary lesion was classified in 4 patterns, irregular geographic pattern, heterogeneous pattern, homogeneous pattern and rim-enhanced pattern. In mediastinal metastatic lymphadenopathy, three enhanced patterns were obtained, heterogeneous, homogeneous and ring enhanced pattern. Some characteristic enhancement patterns according to the histopathological finding of the lung cancer were obtained. With using this incremental slow injection CE-CT, precise information about the relationship between lung cancer and adjacent mediastinal structure, and obvious staining patterns of the tumor and mediastinal lymphnode were recognized. (author)

  19. Superconductivity in CeRh2Si2 Under Pressure

    International Nuclear Information System (INIS)

    Araki, S.; Nakashima, M.; Settai, R.; Kobayashi, T.C.; Onuki, Y.

    2003-01-01

    We have studied the pressure-induced superconductivity in an antiferromagnet CeRh 2 Si 2 by measuring the electrical resistivity for a high-quality single crystal. The superconducting resistivity drop was observed around P c ∼eq 1.06 GPa, at which the Neel temperature becomes zero, namely in a pressure region from 0.97 to 1.20 GPa. The zero resistivity appears below 0.4 K between 1.03 to 1.08 GPa. The resistivity at low temperatures follows the Fermi liquid AT 2 relation in the whole pressure region, even at P c . The A value becomes a maximum around P c . (author)

  20. Scintillation properties of Ce-doped LuLiF{sub 4} and LuScBO{sub 3}

    Energy Technology Data Exchange (ETDEWEB)

    Yanagida, Takayuki, E-mail: t_yanagi@tagen.tohoku.ac.jp [IMRAM, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, Miyagi 980-8577 (Japan); Fujimoto, Yutaka [IMRAM, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, Miyagi 980-8577 (Japan); Kawaguchi, Noriaki [IMRAM, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, Miyagi 980-8577 (Japan); Tokuyama Corporation, Shibuya 3-chome, Shibuya-ku, Tokyo 150-8383 (Japan); Yokota, Yuui [IMRAM, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, Miyagi 980-8577 (Japan); Kamada, Kei [Materials Research Laboratory, Furukawa, Co. Ltd., 1-25-13 Kannondai, Tsukuba, Ibaragi 305-0856 (Japan); Totsuka, Daisuke [Nihon Kessho Kogaku Co., Ltd., 810-5 Nobe-cho, Tatebayashi, Gunma 374-0047 (Japan); Hatamoto, Shun-Ichi [Corporate Research and Development Center, Mitsui Mining and Smelting Co., Ltd., 1333-2 Haraichi, Ageo Saitama 362-0023 (Japan); Yoshikawa, Akira; Chani, Valery [IMRAM, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, Miyagi 980-8577 (Japan)

    2011-10-01

    The crystals of 1 mol% Ce-doped LuLiF{sub 4} (Ce:LLF) grown by the micro-pulling down ({mu}-PD) method and 1 mol% Ce-doped LuScBO{sub 3} (Ce:LSBO) grown by the conventional Czochralski (Cz) method were examined for their scintillation properties. Ce:LLF and Ce:LSBO demonstrated {approx}80% transparency at wavelengths longer than 300 and 400 nm, respectively. When excited by {sup 241}Am {alpha}-ray to obtain radioactive luminescence spectra, Ce{sup 3+} 5d-4f emission peaks were detected at around 320 nm for Ce:LLF and at around 380 nm for Ce:LSBO. In Ce:LSBO, the host luminescence was also observed at 260 nm. By recording pulse height spectra under {gamma}-ray irradiation, the absolute light yield of Ce:LLF and Ce:LSBO was measured to be 3600{+-}400 and 4200{+-}400 ph/MeV, respectively. Decay time kinetics was also investigated using a pulse X-ray equipped streak camera system. The main component of Ce:LLF was {approx}320 ns and that of Ce:LSBO was {approx}31 ns. In addition, the light yield non-proportionality and energy resolution against the {gamma}-ray energy were evaluated.