WorldWideScience

Sample records for abstracts boron americas

  1. Program and Abstracts, Boron Americas IX Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Feakes, Debra A.

    2006-08-09

    The Scientific and Technical Information (STI) submitted includes the final report and a collection of abstracts for the Ninth Boron in the Americas Conference which was held May 19-22, 2004, in San Marcos, Texas. The topics covered in the abstracts include: Application in Medicine, Application in Organic Synthesis and Catalysis, Boranes and Carboranes, Materials and Polymers, Metallaboranes and Metallacarboranes, Organoboron Compounds, Synthesis and Catalysis, and Theoretical Studies. Attendees represented researchers from government, industry, and academia.

  2. Eleventh international conference on boron chemistry. Programme and abstracts

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2002-07-01

    Abstracts of reports at the Eleventh International Conference on Boron Chemistry are presented. Born chemistry as a connecting bridge between many fields maintains one of the leading positions in modern chemistry. Methods of synthesis of different boron compounds, properties of the compounds, their use in other regions of chemistry and medicine are widely presented in reports.

  3. Eleventh international conference on boron chemistry. Programme and abstracts

    International Nuclear Information System (INIS)

    2002-01-01

    Abstracts of reports at the Eleventh International Conference on Boron Chemistry are presented. Born chemistry as a connecting bridge between many fields maintains one of the leading positions in modern chemistry. Methods of synthesis of different boron compounds, properties of the compounds, their use in other regions of chemistry and medicine are widely presented in reports [ru

  4. Boron

    Science.gov (United States)

    Boron is an essential micronutrient element required for plant growth. Boron deficiency is wide-spread in crop plants throughout the world especially in coarse-textured soils in humid areas. Boron toxicity can also occur, especially in arid regions under irrigation. Plants respond directly to the...

  5. Abstracts of the Second energy conference of the Latin America and the Caribbean (ENERLAC'95)

    International Nuclear Information System (INIS)

    1996-01-01

    The Latin American Energy Organization (OLADE), with support from the Ministry of Energy and Mines of Ecuador, held the Second Energy Conference of Latin America and the Caribbean (ENERLAC 95) under the heading Energy Integration and Private-Sector Participation, essentially aimed at bringing together top public and private sector executives of latin america and the caribbean and entrepreneurs, investors, representatives of commercial banks and financial institutions to identify and concretize business opportunities and foster the energy integration of the region by identifying projects and investment opportunities in the sector. The present document is a reference work compiling the abstracts of the presentations that have been submitted and selected for ENERLAC 95. This publication provides a wide range of opinions and ideas about many energy sector topics

  6. Abstracts

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    The Western Theories of War Ethics and Contemporary Controversies Li Xiaodong U Ruijing (4) [ Abstract] In the field of international relations, war ethics is a concept with distinct westem ideological color. Due to factors of history and reality, the in

  7. Physical activity interventions in Latin America: what value might be added by including conference abstracts in a literature review?

    Science.gov (United States)

    Hoehner, Christine; Soares, Jesus; Parra, Diana C; Ribeiro, Isabela C; Pratt, Michael; Bracco, Mario; Hallal, Pedro C; Brownson, Ross C

    2010-07-01

    This review assessed whether conference abstracts yield useful information on the types and effectiveness of community-based physical activity (PA) interventions in Latin America, beyond that from interventions included in a recent systematic review of peer-reviewed literature. Abstracts from 9 conferences were searched for community-based interventions to promote PA in Latin America and summarized. Three reviewers classified and screened abstracts. Evaluated interventions that were not included in the previous review were assessed. Search of abstracts from 31 proceedings of 9 conferences identified 87 abstracts of studies on community-based interventions focused on increasing PA. Only 31 abstracts reported on studies with a control group and an outcome related to PA. Ten of these abstracts represented interventions that had not been included in the previous review of peer-reviewed literature, but the abstracts were insufficient in number or detail to make a practice recommendation for any single intervention. This review highlighted the challenges and low added value of including conference abstracts in a systematic review of community PA interventions in Latin America. Stronger evaluation design and execution and more published reports of evaluated interventions are needed to build an evidence base supporting interventions to increase PA in Latin America.

  8. Abstracts

    Institute of Scientific and Technical Information of China (English)

    2017-01-01

    Supplementary Short Board: Orderly Cultivate Housing Leasing Market WANG Guangtao (Former Minister of Ministry of Construction) Abstract: In December 2016, Central Economic Work Conference proposed that to promote the steady and healthy development of the real estate market, it should adhere to the “house is used to live, not used to speculate” position. At present, the development of housing leasing market in China is lagging behind. It is urgent to improve the housing conditions of large cities and promote the urbanization of small and medium-sized cities. Therefore, it is imperative to innovate and supplement the short board to accelerate the development of housing leasing market.

  9. Abstracts

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    Strategic Realism: An Option for China' s Grand Strategy Song Dexing (4) [ Abstract] As a non-Western emerging power, China should positively adapt its grand strategy to the strategic psychological traits in the 21st century, maintain a realist tone consistent with the national conditions of China, and avoid adventurist policies while awaring both strategic strength and weakness. In the 21st century, China' s grand strategy should be based on such core values as security, development, peace and justice, especially focusing on development in particular, which we named "strategic realism". Given the profound changes in China and the world, strategic realism encourages active foreign policy to safe- guard the long-term national interests of China. Following the self-help logic and the fun- damental values of security and prosperity, strategic realism concerns national interests as its top-priority. It advocates smart use of power, and aims to achieve its objectives by optimizing both domestic and international conditions. From the perspective of diplomatic phi- losophy, strategic realism is not a summarization of concrete policies but a description of China' s grand strategy orientations in the new century. [ Key Words] China, grand strategy, strategic realism [ Author]Song Dexing, Professor, Ph.D. Supervisor, and Director of the Center for International Strategic Studies, University of International Studies of PLA.

  10. Seasonality in the coastal ocean of North America, 35°N - 48°N [abstract

    OpenAIRE

    Strub, Ted; Smith, Robert

    1986-01-01

    EXTRACT (SEE PDF FOR FULL ABSTRACT): The seasonal cycles of coastal wind stress, adjusted sea level height (ASL), shelf currents and water temperatures off the west coast of North America (35°N to 48°N) were estimated by fitting annual and semiannual harmonics to data from 1981-1983. Longer records of monthly ASL indicate that these two harmonics adequately represent the long-term monthly average seasonal cycle, and that the current measurement period is long enough to define the seasonal...

  11. Proceedings of the Seminar on Management Options for Low and Intermediate-Level Wastes in Latin America - Abstracts

    International Nuclear Information System (INIS)

    1986-01-01

    The solutions adapted for management problems on radioactive wastes of nuclear installations and contamined materials generated in hospitals, research centers, laboratories in the countries of Latin America are presented. The criteria of site selection for radioactive waste installation and the methods for treating and storage are evaluated. The results of inspections in installations which handle radioactive wastes are done.(M.C.K.) [pt

  12. Boron Fullerenes: A First-Principles Study

    Directory of Open Access Journals (Sweden)

    Gonzalez Szwacki Nevill

    2007-01-01

    Full Text Available AbstractA family of unusually stable boron cages was identified and examined using first-principles local-density functional method. The structure of the fullerenes is similar to that of the B12icosahedron and consists of six crossing double-rings. The energetically most stable fullerene is made up of 180 boron atoms. A connection between the fullerene family and its precursors, boron sheets, is made. We show that the most stable boron sheets are not necessarily precursors of very stable boron cages. Our finding is a step forward in the understanding of the structure of the recently produced boron nanotubes.

  13. Boron reclamation

    International Nuclear Information System (INIS)

    Smith, R.M.

    1980-07-01

    A process to recover high purity 10 B enriched crystalline boron powder from a polymeric matrix was developed on a laboratory basis and ultimately scaled up to production capacity. The process is based on controlled pyrolysis of boron-filled scrap followed by an acid leach and dry sieving operation to return the powder to the required purity and particle size specifications. Typically, the recovery rate of the crystalline powder is in excess of 98.5 percent, and some of the remaining boron is recovered in the form of boric acid. The minimum purity requirement of the recovered product is 98.6 percent total boron

  14. Superplastic boronizing of duplex stainless steel under dual compression method

    International Nuclear Information System (INIS)

    Jauhari, I.; Yusof, H.A.M.; Saidan, R.

    2011-01-01

    Highlights: → Superplastic boronizing. → Dual compression method has been developed. → Hard boride layer. → Bulk deformation was significantly thicker the boronized layer. → New data on boronizing could be expanded the application of DSS in industries. - Abstract: In this work, SPB of duplex stainless steel (DSS) under compression method is studied with the objective to produce ultra hard and thick boronized layer using minimal amount of boron powder and at a much faster boronizing time as compared to the conventional process. SPB is conducted under dual compression methods. In the first method DSS is boronized using a minimal amount of boron powder under a fix pre-strained compression condition throughout the process. The compression strain is controlled in such a way that plastic deformation is restricted at the surface asperities of the substrate in contact with the boron powder. In the second method, the boronized specimen taken from the first mode is compressed superplastically up to a certain compressive strain under a certain strain rate condition. The process in the second method is conducted without the present of boron powder. As compared with the conventional boronizing process, through this SPB under dual compression methods, a much harder and thicker boronized layer thickness is able to be produced using a minimal amount of boron powder.

  15. Superplastic boronizing of duplex stainless steel under dual compression method

    Energy Technology Data Exchange (ETDEWEB)

    Jauhari, I., E-mail: iswadi@um.edu.my [Department of Mechanical Engineering, Faculty of Engineering, University of Malaya, 50603 Kuala Lumpur (Malaysia); Yusof, H.A.M.; Saidan, R. [Department of Mechanical Engineering, Faculty of Engineering, University of Malaya, 50603 Kuala Lumpur (Malaysia)

    2011-10-25

    Highlights: {yields} Superplastic boronizing. {yields} Dual compression method has been developed. {yields} Hard boride layer. {yields} Bulk deformation was significantly thicker the boronized layer. {yields} New data on boronizing could be expanded the application of DSS in industries. - Abstract: In this work, SPB of duplex stainless steel (DSS) under compression method is studied with the objective to produce ultra hard and thick boronized layer using minimal amount of boron powder and at a much faster boronizing time as compared to the conventional process. SPB is conducted under dual compression methods. In the first method DSS is boronized using a minimal amount of boron powder under a fix pre-strained compression condition throughout the process. The compression strain is controlled in such a way that plastic deformation is restricted at the surface asperities of the substrate in contact with the boron powder. In the second method, the boronized specimen taken from the first mode is compressed superplastically up to a certain compressive strain under a certain strain rate condition. The process in the second method is conducted without the present of boron powder. As compared with the conventional boronizing process, through this SPB under dual compression methods, a much harder and thicker boronized layer thickness is able to be produced using a minimal amount of boron powder.

  16. Proceedings of workshop on 'boron science and boron neutron capture therapy'

    Energy Technology Data Exchange (ETDEWEB)

    Kitaoka, Y. [ed.

    1998-12-01

    This volume contains the abstracts and programs of the 8th (1996), 9th (1997) and 10th (1998) of the workshop on 'the Boron Science and Boron Neutron Capture Therapy' and the recent progress reports especially subscribed. The 11 of the presented papers are indexed individually. (J.P.N.)

  17. Boron stress response and accumulation potential of the extremely tolerant species Puccinellia frigida

    International Nuclear Information System (INIS)

    Rámila, Consuelo d.P.; Contreras, Samuel A.; Di Domenico, Camila; Molina-Montenegro, Marco A.; Vega, Andrea; Handford, Michael; Bonilla, Carlos A.

    2016-01-01

    Highlights: • P. frigida presents an extremely high boron toxicity threshold. • Restricting uptake and internal tolerance mechanisms could confer boron tolerance. • P. frigida is a boron hyperaccumulator over a wide range of concentrations. • The species has potential for phytoremediation purposes. - Abstract: Phytoremediation is a promising technology to tackle boron toxicity, which restricts agricultural activities in many arid and semi-arid areas. Puccinellia frigida is a perennial grass that was reported to hyperaccumulate boron in extremely boron-contaminated sites. To further investigate its potential for phytoremediation, we determined its response to boron stress under controlled conditions (hydroponic culture). Also, as a first step towards understanding the mechanisms underlying its extreme tolerance, we evaluated the presence and expression of genes related with boron tolerance. We found that P. frigida grew normally even at highly toxic boron concentrations in the medium (500 mg/L), and within its tissues (>5000 mg/kg DW). We postulate that the strategies conferring this extreme tolerance involve both restricting boron accumulation and an internal tolerance mechanism; this is consistent with the identification of putative genes involved in both mechanisms, including the expression of a possible boron efflux transporter. We also found that P. frigida hyperaccumulated boron over a wide range of boron concentrations. We propose that P. frigida could be used for boron phytoremediation strategies in places with different soil characteristics and boron concentrations. Further studies should pave the way for the development of clean and low-cost solutions to boron toxicity problems.

  18. Boron stress response and accumulation potential of the extremely tolerant species Puccinellia frigida

    Energy Technology Data Exchange (ETDEWEB)

    Rámila, Consuelo d.P. [Departamento de Ingeniería Hidráulica y Ambiental, Pontificia Universidad Católica de Chile, Avenida Vicuña Mackenna 4860, 7820436 Santiago (Chile); Contreras, Samuel A.; Di Domenico, Camila [Facultad de Agronomía e Ingeniería Forestal, Pontificia Universidad Católica de Chile, Avenida Vicuña Mackenna 4860, 7820436 Santiago (Chile); Molina-Montenegro, Marco A. [Centro de Estudios Avanzados en Zonas Áridas (CEAZA), Facultad de Ciencias del Mar, Universidad Católica del Norte, Larrondo 1281, Coquimbo (Chile); Instituto de Ciencias Biológicas, Universidad de Talca, Avda. Lircay s/n, Talca (Chile); Vega, Andrea [Facultad de Agronomía e Ingeniería Forestal, Pontificia Universidad Católica de Chile, Avenida Vicuña Mackenna 4860, 7820436 Santiago (Chile); Handford, Michael [Departmento de Biología, Facultad de Ciencias, Universidad de Chile, Avenida Las Palmeras 3425, 7800024 Santiago (Chile); Bonilla, Carlos A. [Departamento de Ingeniería Hidráulica y Ambiental, Pontificia Universidad Católica de Chile, Avenida Vicuña Mackenna 4860, 7820436 Santiago (Chile); Centro de Desarrollo Urbano Sustentable (CEDEUS), Pontificia Universidad Católica de Chile, Avenida Vicuña Mackenna 4860, 7820436 Santiago (Chile); and others

    2016-11-05

    Highlights: • P. frigida presents an extremely high boron toxicity threshold. • Restricting uptake and internal tolerance mechanisms could confer boron tolerance. • P. frigida is a boron hyperaccumulator over a wide range of concentrations. • The species has potential for phytoremediation purposes. - Abstract: Phytoremediation is a promising technology to tackle boron toxicity, which restricts agricultural activities in many arid and semi-arid areas. Puccinellia frigida is a perennial grass that was reported to hyperaccumulate boron in extremely boron-contaminated sites. To further investigate its potential for phytoremediation, we determined its response to boron stress under controlled conditions (hydroponic culture). Also, as a first step towards understanding the mechanisms underlying its extreme tolerance, we evaluated the presence and expression of genes related with boron tolerance. We found that P. frigida grew normally even at highly toxic boron concentrations in the medium (500 mg/L), and within its tissues (>5000 mg/kg DW). We postulate that the strategies conferring this extreme tolerance involve both restricting boron accumulation and an internal tolerance mechanism; this is consistent with the identification of putative genes involved in both mechanisms, including the expression of a possible boron efflux transporter. We also found that P. frigida hyperaccumulated boron over a wide range of boron concentrations. We propose that P. frigida could be used for boron phytoremediation strategies in places with different soil characteristics and boron concentrations. Further studies should pave the way for the development of clean and low-cost solutions to boron toxicity problems.

  19. Friction anisotropy in boronated graphite

    International Nuclear Information System (INIS)

    Kumar, N.; Radhika, R.; Kozakov, A.T.; Pandian, R.; Chakravarty, S.; Ravindran, T.R.; Dash, S.; Tyagi, A.K.

    2015-01-01

    Graphical abstract: - Highlights: • Friction anisotropy in boronated graphite is observed in macroscopic sliding condition. • Low friction coefficient is observed in basal plane and becomes high in prismatic direction. • 3D phase of boronated graphite transformed into 2D structure after friction test. • Chemical activity is high in prismatic plane forming strong bonds between the sliding interfaces. - Abstract: Anisotropic friction behavior in macroscopic scale was observed in boronated graphite. Depending upon sliding speed and normal loads, this value was found to be in the range 0.1–0.35 in the direction of basal plane and becomes high 0.2–0.8 in prismatic face. Grazing-incidence X-ray diffraction analysis shows prominent reflection of (0 0 2) plane at basal and prismatic directions of boronated graphite. However, in both the wear tracks (1 1 0) plane become prominent and this transformation is induced by frictional energy. The structural transformation in wear tracks is supported by micro-Raman analysis which revealed that 3D phase of boronated graphite converted into a disordered 2D lattice structure. Thus, the structural aspect of disorder is similar in both the wear tracks and graphite transfer layers. Therefore, the crystallographic aspect is not adequate to explain anisotropic friction behavior. Results of X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy shows weak signature of oxygen complexes and functional groups in wear track of basal plane while these species dominate in prismatic direction. Abundance of these functional groups in prismatic plane indicates availability of chemically active sites tends to forming strong bonds between the sliding interfaces which eventually increases friction coefficient

  20. Friction anisotropy in boronated graphite

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, N., E-mail: niranjan@igcar.gov.in [Materials Science Group, Indira Gandhi Centre for Atomic Research, Kalpakkam (India); Radhika, R. [Crystal Growth Centre, Anna University, Chennai (India); Kozakov, A.T. [Research Institute of Physics, Southern Federal University, Rostov-on-Don (Russian Federation); Pandian, R. [Materials Science Group, Indira Gandhi Centre for Atomic Research, Kalpakkam (India); Chakravarty, S. [UGC-DAE CSR, Kalpakkam (India); Ravindran, T.R.; Dash, S.; Tyagi, A.K. [Materials Science Group, Indira Gandhi Centre for Atomic Research, Kalpakkam (India)

    2015-01-01

    Graphical abstract: - Highlights: • Friction anisotropy in boronated graphite is observed in macroscopic sliding condition. • Low friction coefficient is observed in basal plane and becomes high in prismatic direction. • 3D phase of boronated graphite transformed into 2D structure after friction test. • Chemical activity is high in prismatic plane forming strong bonds between the sliding interfaces. - Abstract: Anisotropic friction behavior in macroscopic scale was observed in boronated graphite. Depending upon sliding speed and normal loads, this value was found to be in the range 0.1–0.35 in the direction of basal plane and becomes high 0.2–0.8 in prismatic face. Grazing-incidence X-ray diffraction analysis shows prominent reflection of (0 0 2) plane at basal and prismatic directions of boronated graphite. However, in both the wear tracks (1 1 0) plane become prominent and this transformation is induced by frictional energy. The structural transformation in wear tracks is supported by micro-Raman analysis which revealed that 3D phase of boronated graphite converted into a disordered 2D lattice structure. Thus, the structural aspect of disorder is similar in both the wear tracks and graphite transfer layers. Therefore, the crystallographic aspect is not adequate to explain anisotropic friction behavior. Results of X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy shows weak signature of oxygen complexes and functional groups in wear track of basal plane while these species dominate in prismatic direction. Abundance of these functional groups in prismatic plane indicates availability of chemically active sites tends to forming strong bonds between the sliding interfaces which eventually increases friction coefficient.

  1. A convenient catalyst system for microwave accelerated cross-coupling of a range of aryl boronic acids with aryl chlorides

    Directory of Open Access Journals (Sweden)

    Milton Edward J

    2007-05-01

    Full Text Available Abstract A convenient microwave accelerated cross-coupling procedure between aryl chlorides with a range of boronic acids has been developed. An explanation for the low reactivity of highly fluorinated boronic acids in Suzuki coupling is provided.

  2. Aspects of the chemistry of boron

    International Nuclear Information System (INIS)

    Moellinger, H.

    1976-01-01

    Crystal phases of elementary boron are reviewed as well as boron-sulphur, boron-selenum, boron-tellurium, and boron-nitrogen compounds, carboranes, and boron-carbohydrate complexes. A boron cadastre of rivers and lakes serves to illustrate the role of boron in environmental protection. Technically relevant boron compounds and their uses are mentioned. (orig.) 891 HK/orig. 892 MB [de

  3. Removal of boron from aqueous solution using cryptocrystalline magnesite

    CSIR Research Space (South Africa)

    Masindi, Vhahangwele

    2016-05-01

    Full Text Available of Water Reuse and Desalination Removal of boron from aqueous solution using cryptocrystalline magnesite Vhahangwele Masindi and Mugera W. Gitari Abstract The present study aimed to evaluate the efficiency of using cryptocrystalline magnesite...

  4. Structure and reactivity of boron-ate complexes derived from primary and secondary boronic esters.

    Science.gov (United States)

    Feeney, Kathryn; Berionni, Guillaume; Mayr, Herbert; Aggarwal, Varinder K

    2015-06-05

    Boron-ate complexes derived from primary and secondary boronic esters and aryllithiums have been isolated, and the kinetics of their reactions with carbenium ions studied. The second-order rate constants have been used to derive nucleophilicity parameters for the boron-ate complexes, revealing that nucleophilicity increased with (i) electron-donating aromatics on boron, (ii) neopentyl glycol over pinacol boronic esters, and (iii) 12-crown-4 ether.

  5. Roles of ATR1 paralogs YMR279c and YOR378w in boron stress tolerance

    International Nuclear Information System (INIS)

    Bozdag, Gonensin Ozan; Uluisik, Irem; Gulculer, Gulce Sila; Karakaya, Huseyin C.; Koc, Ahmet

    2011-01-01

    Highlights: → ATR1 paralog YMR279c plays role in boron detoxification. → YMR279c overexpression lowers cytoplasmic boron levels. → ATR1 paralog YOR378w has no roles in boron stress response. -- Abstract: Boron is a necessary nutrient for plants and animals, however excess of it causes toxicity. Previously, Atr1 and Arabidopsis Bor1 homolog were identified as the boron efflux pump in yeast, which lower the cytosolic boron concentration and help cells to survive in the presence of toxic amount of boron. In this study, we analyzed ATR1 paralogs, YMR279c and YOR378w, to understand whether they participate in boron stress tolerance in yeast. Even though these genes share homology with ATR1, neither their deletion rendered cells boron sensitive nor their expression was significantly upregulated by boron treatment. However, expression of YMR279, but not YOR378w, from the constitutive GAPDH promoter on a high copy plasmid provided remarkable boron resistance by decreasing intracellular boron levels. Thus our results suggest the presence of a third boron exporter, YMR279c, which functions similar to ATR1 and provides boron resistance in yeast.

  6. Abstract algebra

    CERN Document Server

    Garrett, Paul B

    2007-01-01

    Designed for an advanced undergraduate- or graduate-level course, Abstract Algebra provides an example-oriented, less heavily symbolic approach to abstract algebra. The text emphasizes specifics such as basic number theory, polynomials, finite fields, as well as linear and multilinear algebra. This classroom-tested, how-to manual takes a more narrative approach than the stiff formalism of many other textbooks, presenting coherent storylines to convey crucial ideas in a student-friendly, accessible manner. An unusual feature of the text is the systematic characterization of objects by universal

  7. Article Abstract

    African Journals Online (AJOL)

    Abstract. Simple learning tools to improve clinical laboratory practical skills training. B Taye, BSc, MPH. Addis Ababa University, College of Health Sciences, Addis Ababa, ... concerns about the competence of medical laboratory science graduates. ... standardised practical learning guides and assessment checklists would.

  8. Inventory Abstraction

    International Nuclear Information System (INIS)

    Leigh, C.

    2000-01-01

    The purpose of the inventory abstraction as directed by the development plan (CRWMS M and O 1999b) is to: (1) Interpret the results of a series of relative dose calculations (CRWMS M and O 1999c, 1999d). (2) Recommend, including a basis thereof, a set of radionuclides that should be modeled in the Total System Performance Assessment in Support of the Site Recommendation (TSPA-SR) and the Total System Performance Assessment in Support of the Final Environmental Impact Statement (TSPA-FEIS). (3) Provide initial radionuclide inventories for the TSPA-SR and TSPA-FEIS models. (4) Answer the U.S. Nuclear Regulatory Commission (NRC)'s Issue Resolution Status Report ''Key Technical Issue: Container Life and Source Term'' (CLST IRSR) (NRC 1999) key technical issue (KTI): ''The rate at which radionuclides in SNF [Spent Nuclear Fuel] are released from the EBS [Engineered Barrier System] through the oxidation and dissolution of spent fuel'' (Subissue 3). The scope of the radionuclide screening analysis encompasses the period from 100 years to 10,000 years after the potential repository at Yucca Mountain is sealed for scenarios involving the breach of a waste package and subsequent degradation of the waste form as required for the TSPA-SR calculations. By extending the time period considered to one million years after repository closure, recommendations are made for the TSPA-FEIS. The waste forms included in the inventory abstraction are Commercial Spent Nuclear Fuel (CSNF), DOE Spent Nuclear Fuel (DSNF), High-Level Waste (HLW), naval Spent Nuclear Fuel (SNF), and U.S. Department of Energy (DOE) plutonium waste. The intended use of this analysis is in TSPA-SR and TSPA-FEIS. Based on the recommendations made here, models for release, transport, and possibly exposure will be developed for the isotopes that would be the highest contributors to the dose given a release to the accessible environment. The inventory abstraction is important in assessing system performance because

  9. INVENTORY ABSTRACTION

    International Nuclear Information System (INIS)

    Ragan, G.

    2001-01-01

    The purpose of the inventory abstraction, which has been prepared in accordance with a technical work plan (CRWMS M andO 2000e for/ICN--02 of the present analysis, and BSC 2001e for ICN 03 of the present analysis), is to: (1) Interpret the results of a series of relative dose calculations (CRWMS M andO 2000c, 2000f). (2) Recommend, including a basis thereof, a set of radionuclides that should be modeled in the Total System Performance Assessment in Support of the Site Recommendation (TSPA-SR) and the Total System Performance Assessment in Support of the Final Environmental Impact Statement (TSPA-FEIS). (3) Provide initial radionuclide inventories for the TSPA-SR and TSPA-FEIS models. (4) Answer the U.S. Nuclear Regulatory Commission (NRC)'s Issue Resolution Status Report ''Key Technical Issue: Container Life and Source Term'' (CLST IRSR) key technical issue (KTI): ''The rate at which radionuclides in SNF [spent nuclear fuel] are released from the EBS [engineered barrier system] through the oxidation and dissolution of spent fuel'' (NRC 1999, Subissue 3). The scope of the radionuclide screening analysis encompasses the period from 100 years to 10,000 years after the potential repository at Yucca Mountain is sealed for scenarios involving the breach of a waste package and subsequent degradation of the waste form as required for the TSPA-SR calculations. By extending the time period considered to one million years after repository closure, recommendations are made for the TSPA-FEIS. The waste forms included in the inventory abstraction are Commercial Spent Nuclear Fuel (CSNF), DOE Spent Nuclear Fuel (DSNF), High-Level Waste (HLW), naval Spent Nuclear Fuel (SNF), and U.S. Department of Energy (DOE) plutonium waste. The intended use of this analysis is in TSPA-SR and TSPA-FEIS. Based on the recommendations made here, models for release, transport, and possibly exposure will be developed for the isotopes that would be the highest contributors to the dose given a release

  10. BALWOIS: Abstracts

    International Nuclear Information System (INIS)

    Morell, Morell; Todorovik, Olivija; Dimitrov, Dobri

    2004-01-01

    anthropogenic pressures and international shared water. Here are the 320 abstracts proposed by authors and accepted by the Scientific Committee. More than 200 papers are presented during the Conference on 8 topics related to Hydrology, Climatology and Hydro biology: - Climate and Environment; - Hydrological regimes and water balances; - Droughts and Floods; -Integrated Water Resources Management; -Water bodies Protection and Eco hydrology; -Lakes; -Information Systems for decision support; -Hydrological modelling. Papers relevant to INIS are indexed separately

  11. Pulverization of boron element and proportions of boron carbide in boron

    International Nuclear Information System (INIS)

    Lang, F.M.; Finck, C.

    1956-01-01

    It is possible to reduce boron element into fine powder by means of a mortar and pestle made of sintered boron carbide, the ratio of boron carbide introduced being less than one per cent. Boron element at our disposal is made of sharp edged, dark brown, little grains of average size greater than 5 μ. Grain sizes smaller than 1μ are required for applying thin layers of such boron. (author) [fr

  12. Density functional theory investigation of oxygen interaction with boron-doped graphite

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Juan; Wang, Chen [State Key Lab of New Ceramic and Fine Processing, Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084 (China); Liang, Tongxiang, E-mail: txliang@tsinghua.edu.cn [State Key Lab of New Ceramic and Fine Processing, Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084 (China); Lai, Wensheng [Advanced Material Laboratory, School of Materials Science & Engineering, Tsinghua University, Beijing, 100084 (China)

    2016-12-30

    Highlights: • Density-functional approach is applied to study the interaction of oxygen with boron-doped graphite. • Adsorption and diffusion of oxygen atoms on boron doped graphite surfaces are studied. • Recombination of oxygen is investigated by ER and LH mechanisms. • Low boron concentration facilitates O{sub 2} formation while high boron loading inhibits the recombination. • The presence of B−B bonds due to boron accumulation makes it impossible for oxygen recombination. - Abstract: Boron inserted as impurity by substitution of carbon atoms in graphite is known to change (improve or deteriorate) oxidation resistance of nuclear graphite, but the reason for both catalytic and inhibiting oxidation is still uncertain. As a first step, this work is more specially devoted to the adsorption and diffusion of oxygen atoms on the surface and related to the problem of oxygen retention on the pure and boron-containing graphite surfaces. Adsorption energies and energy barriers associated to the diffusion for molecular oxygen recombination are calculated in the density functional theory framework. The existence of boron modifies the electronic structure of the surface, which results in an increase of the adsorption energy for O. However, low boron loading makes it easier for the recombination into molecular oxygen. For high boron concentration, it induces a better O retention capability in graphite because the presence of B-B bonds decreases recombination of the adsorbed oxygen atoms. A possible explanation for both catalytic and inhibiting effects of boron in graphite is proposed.

  13. Shock Response of Boron Carbide

    National Research Council Canada - National Science Library

    Dandekar, D. P. (Dattatraya Purushottam)

    2001-01-01

    .... The present work was undertaken to determine tensile/spall strength of boron carbide under plane shock wave loading and to analyze all available shock compression data on boron carbide materials...

  14. Boronated liposome development and evaluation

    International Nuclear Information System (INIS)

    Hawthorne, M.F.

    1995-01-01

    The boronated liposome development and evaluation effort consists of two separate tasks. The first is the development of new boron compounds and the synthesis of known boron species with BNCT potential. These compounds are then encapsulated within liposomes for the second task, biodistribution testing in tumor-bearing mice, which examines the potential for the liposomes and their contents to concentrate boron in cancerous tissues

  15. Implantation of boron in silicon

    International Nuclear Information System (INIS)

    Hofker, W.K.

    1975-01-01

    The distribution versus depth of boron implanted in silicon and the corresponding electrical activity obtained after annealing are studied. The boron distributions are measured by secondary-ion mass spectrometry. Boron distributions implanted at energies in the range from 30 keV to 800 keV in amorphous and polycrystalline silicon are analysed. Moments of these distributions are determined by a curve-fitting programme and compared with moments calculated by Winterbon. Boron distributions obtained by implantations along a dense crystallographic direction in monocrystalline silicon are found to have penetrating tails. After investigation of some possible mechanisms of tail formation it is concluded that the tails are due to channelling. It was found that the behaviour of boron during annealing is determined by the properties of three boron fractions consisting of precipitated boron, interstitial boron and substitutional boron. The electrical activity of the boron versus depth is found to be consistent with the three boron fractions. A peculiar redistribution of boron is found which is induced by the implantation of a high dose of heavy ions and subsequent annealing. Different mechanisms which may cause the observed effects, such as thermal diffusion which is influenced by lattice strain and damage, are discussed. (Auth.)

  16. Enrichment of boron 10

    International Nuclear Information System (INIS)

    Coutinho, C.M.M.; Rodrigues Filho, J.S.R.; Umeda, K.; Echternacht, M.V.

    1990-01-01

    A isotopic separation pilot plant with five ion exchange columns interconnected in series were designed and built in the IEN. The columns are charged with a strong anionic resin in its alkaline form. The boric acid solution is introduced in the separation columns until it reaches a absorbing zone length which is sufficient to obtain the desired boron-10 isotopic concentration. The boric acid absorbing zone movement is provided by the injection of a diluted hydrochloric acid solution, which replace the boric acid throughout the columns. The absorbing zone equilibrium length is proportional to its total length. The enriched boron-10 and the depleted boron are located in the final boundary and in the initial position of the absorbing zones, respectively. (author)

  17. Structure and photoluminescence of boron and nitrogen co-doped carbon nanorods

    Energy Technology Data Exchange (ETDEWEB)

    Wang, B.B. [College of Chemistry and Chemical Engineering, Chongqing University of Technology, 69 Hongguang Rd, Lijiatuo, Banan District, Chongqing 400054 (China); Gao, B. [College of Computer Science, Chongqing University, Chongqing 400044 (China); Chongqing Municipal Education Examinations Authority, Chongqing 401147 (China); Zhong, X.X., E-mail: xxzhong@sjtu.edu.cn [Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240 (China); Shao, R.W.; Zheng, K. [Institute of Microstructure and Properties of Advanced Materials, Beijing University of Technology, Beijing 100124 (China)

    2016-07-15

    Graphical abstract: Boron- and nitrogen- doped carbon nanorods. - Highlights: • The co-doping of nitrogen and boron in carbon nanorods. • The doping mechanism of nitrogen and boron in carbon nanorods by plasma. • Photoluminescence properties of nitrogen- and boron-doped carbon nanorods. - Abstract: Boron and nitrogen doped carbon nanorods (BNCNRs) were synthesized by plasma-enhanced hot filament chemical vapor deposition, where methane, nitrogen and hydrogen were used as the reaction gases and boron carbide was the boron source. The results of scanning electron microscopy, micro-Raman spectroscopy, transmission electron microscopy and X-ray photoelectron spectroscopy indicate that boron and nitrogen can be used as co-dopants in amorphous carbon nanorods. Combined with the characterization results, the doping mechanism was studied. The mechanism is used to explain the formation of different carbon materials by different methods. The photoluminescence (PL) properties of BNCNRs were studied. The PL results show that the BNCNRs generate strong green PL bands and weak blue PL bands, and the PL intensity lowered due to the doping of boron. The outcomes advance our knowledge on the synthesis and optical properties of carbon-based nanomaterials and contribute to the development of optoelectronic nanodevices based on nano-carbon mateirals.

  18. Thermoelectric properties of boron and boron phosphide CVD wafers

    Energy Technology Data Exchange (ETDEWEB)

    Kumashiro, Y.; Yokoyama, T.; Sato, A.; Ando, Y. [Yokohama National Univ. (Japan)

    1997-10-01

    Electrical and thermal conductivities and thermoelectric power of p-type boron and n-type boron phosphide wafers with amorphous and polycrystalline structures were measured up to high temperatures. The electrical conductivity of amorphous boron wafers is compatible to that of polycrystals at high temperatures and obeys Mott`s T{sup -{1/4}} rule. The thermoelectric power of polycrystalline boron decreases with increasing temperature, while that of amorphous boron is almost constant in a wide temperature range. The weak temperature dependence of the thermal conductivity of BP polycrystalline wafers reflects phonon scattering by grain boundaries. Thermal conductivity of an amorphous boron wafer is almost constant in a wide temperature range, showing a characteristic of a glass. The figure of merit of polycrystalline BP wafers is 10{sup -7}/K at high temperatures while that of amorphous boron is 10{sup -5}/K.

  19. Effect of boron on the microstructure and mechanical properties of carbidic austempered ductile iron

    International Nuclear Information System (INIS)

    Peng Yuncheng; Jin Huijin; Liu Jinhai; Li Guolu

    2011-01-01

    Highlights: → Boron are applied to carbidic austempered ductile iron (CADI). → Boron microalloying CADI is a new high hardenability of wear-resistant cast iron. → Addition of boron to CADI significantly improves hardenability. → Effect of boron on the CADI grinding ball were investigated. → Optimum property is obtained when boron content at 0.03 wt%. - Abstract: Carbidic austempered ductile iron (CADI) castings provide a unique combination of high hardness and toughness coupled with superior wear resistance properties, but their hardenability restricts their range of applications. The purpose of this study was to investigate the influence of boron on the microstructure and mechanical properties of CADI. The experimental results indicate that the CADI comprises graphite nodules, which are dispersive boron-carbides that are distributed in the form of strips, and the matrix is a typical ausferritic matrix. Microscopic amounts of boron can improve the hardenability of CADI, but higher boron content reduces the hardenability and toughness of CADI. The results are discussed in the context of the influence of boron content on the microstructure and mechanical properties of grinding balls.

  20. Facile Synthesis of Ternary Boron Carbonitride Nanotubes

    Directory of Open Access Journals (Sweden)

    Luo Lijie

    2009-01-01

    Full Text Available Abstract In this study, a novel and facile approach for the synthesis of ternary boron carbonitride (B–C–N nanotubes was reported. Growth occurred by heating simple starting materials of boron powder, zinc oxide powder, and ethanol absolute at 1150 °C under a mixture gas flow of nitrogen and hydrogen. As substrate, commercial stainless steel foil with a typical thickness of 0.05 mm played an additional role of catalyst during the growth of nanotubes. The nanotubes were characterized by SEM, TEM, EDX, and EELS. The results indicate that the synthesized B–C–N nanotubes exhibit a bamboo-like morphology and B, C, and N elements are homogeneously distributed in the nanotubes. A catalyzed vapor–liquid–solid (VLS mechanism was proposed for the growth of the nanotubes.

  1. Structural Modification in Carbon Nanotubes by Boron Incorporation

    Directory of Open Access Journals (Sweden)

    Handuja Sangeeta

    2009-01-01

    Full Text Available Abstract We have synthesized boron-incorporated carbon nanotubes (CNTs by decomposition of ferrocene and xylene in a thermal chemical vapor deposition set up using boric acid as the boron source. Scanning and transmission electron microscopy studies of the synthesized CNT samples showed that there was deterioration in crystallinity and improvement in alignment of the CNTs as the boron content in precursor solution increased from 0% to 15%. Raman analysis of these samples showed a shift of ~7 cm−1in wave number to higher side and broadening of the G band with increasing boron concentration along with an increase in intensity of the G band. Furthermore, there was an increase in the intensity of the D band along with a decrease in its wave number position with increase in boron content. We speculate that these structural modifications in the morphology and microstructure of CNTs might be due to the charge transfer from boron to the graphite matrix, resulting in shortening of the carbon–carbon bonds.

  2. Interaction of boron with graphite: A van der Waals density functional study

    International Nuclear Information System (INIS)

    Liu, Juan; Wang, Chen; Liang, Tongxiang; Lai, Wensheng

    2016-01-01

    Highlights: • A van der Waals density-functional approach is applied to study the interaction of boron with graphite. • VdW-DF functionals give fair agreement of crystal parameters with experiments. • The π electron approaches boron while adsorbing on graphite surface. • The hole introduced by boron mainly concentrates on boron and the nearest three carbon atoms. • PBE cannot describe the interstitial boron in graphite because of the ignoring binding of graphite sheets. - Abstract: Boron doping has been widely investigated to improve oxidation resistance of graphite. In this work the interaction of boron with graphite is investigated by a van der Waals density-functional approach (vdW-DF). The traditional density-functional theory (DFT) is well accounted for the binding in boron-substituted graphite. However, to investigate the boron atom on graphite surface and the interstitial impurities require use of a description of graphite interlayer binding. Traditional DFT cannot describe the vdW physics, for instance, GGA calculations show no relevant binding between graphite sheets. LDA shows some binding, but they fail to provide an accurate account of vdW forces. In this paper, we compare the calculation results of graphite lattice constant and cohesive energy by several functionals, it shows that vdW-DF such as two optimized functionals optB88-vdW and optB86b-vdW give much improved results than traditional DFT. The vdW-DF approach is then applied to study the interaction of boron with graphite. Boron adsorption, substitution, and intercalation are discussed in terms of structural parameters and electronic structures. When adsorbing on graphite surface, boron behaves as π electron acceptor. The π electron approaches boron atom because of more electropositive of boron than carbon. For substitution situation, the hole introduced by boron mainly concentrates on boron and the nearest three carbon atoms. The B-doped graphite system with the hole has less

  3. Interaction of boron with graphite: A van der Waals density functional study

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Juan; Wang, Chen [Beijing Key Lab of Fine Ceramics, Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084 (China); Liang, Tongxiang, E-mail: txliang@tsinghua.edu.cn [State Key Lab of New Ceramic and Fine Processing, Tsinghua University, Beijing 100084 (China); Lai, Wensheng [Advanced Material Laboratory, School of Materials Science & Engineering, Tsinghua University, Beijing, 100084 (China)

    2016-08-30

    Highlights: • A van der Waals density-functional approach is applied to study the interaction of boron with graphite. • VdW-DF functionals give fair agreement of crystal parameters with experiments. • The π electron approaches boron while adsorbing on graphite surface. • The hole introduced by boron mainly concentrates on boron and the nearest three carbon atoms. • PBE cannot describe the interstitial boron in graphite because of the ignoring binding of graphite sheets. - Abstract: Boron doping has been widely investigated to improve oxidation resistance of graphite. In this work the interaction of boron with graphite is investigated by a van der Waals density-functional approach (vdW-DF). The traditional density-functional theory (DFT) is well accounted for the binding in boron-substituted graphite. However, to investigate the boron atom on graphite surface and the interstitial impurities require use of a description of graphite interlayer binding. Traditional DFT cannot describe the vdW physics, for instance, GGA calculations show no relevant binding between graphite sheets. LDA shows some binding, but they fail to provide an accurate account of vdW forces. In this paper, we compare the calculation results of graphite lattice constant and cohesive energy by several functionals, it shows that vdW-DF such as two optimized functionals optB88-vdW and optB86b-vdW give much improved results than traditional DFT. The vdW-DF approach is then applied to study the interaction of boron with graphite. Boron adsorption, substitution, and intercalation are discussed in terms of structural parameters and electronic structures. When adsorbing on graphite surface, boron behaves as π electron acceptor. The π electron approaches boron atom because of more electropositive of boron than carbon. For substitution situation, the hole introduced by boron mainly concentrates on boron and the nearest three carbon atoms. The B-doped graphite system with the hole has less

  4. Boron Neutron Capture Therapy (BCNT) for the Treatment of Liver Metastases: Biodistribution Studies of Boron Compounds in an Experimental Model

    Energy Technology Data Exchange (ETDEWEB)

    Marcela A. Garabalino; Andrea Monti Hughes; Ana J. Molinari; Elisa M. Heber; Emiliano C. C. Pozzi; Maria E. Itoiz; Veronica A. Trivillin; Amanda E. Schwint; Jorge E. Cardoso; Lucas L. Colombo; Susana Nievas; David W. Nigg; Romina F. Aromando

    2011-03-01

    Abstract We previously demonstrated the therapeutic efficacy of different boron neutron capture therapy (BNCT) protocols in an experimental model of oral cancer. BNCT is based on the selective accumulation of 10B carriers in a tumor followed by neutron irradiation. Within the context of exploring the potential therapeutic efficacy of BNCT for the treatment of liver metastases, the aim of the present study was to perform boron biodistribution studies in an experimental model of liver metastases in rats. Different boron compounds and administration conditions were assayed to determine which administration protocols would potentially be therapeutically useful in in vivo BNCT studies at the RA-3 nuclear reactor. A total of 70 BDIX rats were inoculated in the liver with syngeneic colon cancer cells DHD/K12/TRb to induce the development of subcapsular tumor nodules. Fourteen days post-inoculation, the animals were used for biodistribution studies. We evaluated a total of 11 administration protocols for the boron compounds boronophenylalanine (BPA) and GB-10 (Na210B10H10), alone or combined at different dose levels and employing different administration routes. Tumor, normal tissue, and blood samples were processed for boron measurement by atomic emission spectroscopy. Six protocols proved potentially useful for BNCT studies in terms of absolute boron concentration in tumor and preferential uptake of boron by tumor tissue. Boron concentration values in tumor and normal tissues in the liver metastases model show it would be feasible to reach therapeutic BNCT doses in tumor without exceeding radiotolerance in normal tissue at the thermal neutron facility at RA-3.

  5. A New Boron Analysis Method

    Energy Technology Data Exchange (ETDEWEB)

    Weitman, J; Daaverhoeg, N; Farvolden, S

    1970-07-01

    In connection with fast neutron (n, {alpha}) cross section measurements a novel boron analysis method has been developed. The boron concentration is inferred from the mass spectrometrically determined number of helium atoms produced in the thermal and epithermal B-10 (n, {alpha}) reaction. The relation between helium amount and boron concentration is given, including corrections for self shielding effects and background levels. Direct and diffusion losses of helium are calculated and losses due to gettering, adsorption and HF-ionization in the release stage are discussed. A series of boron determinations is described and the results are compared with those obtained by other methods, showing excellent agreement. The lower limit of boron concentration which can be measured varies with type of sample. In e.g. steel, concentrations below 10-5 % boron in samples of 0.1-1 gram may be determined.

  6. Folate Functionalized Boron Nitride Nanotubes and their Selective Uptake by Glioblastoma Multiforme Cells: Implications for their Use as Boron Carriers in Clinical Boron Neutron Capture Therapy

    Directory of Open Access Journals (Sweden)

    Ciofani Gianni

    2008-01-01

    Full Text Available Abstract Boron neutron capture therapy (BNCT is increasingly being used in the treatment of several aggressive cancers, including cerebral glioblastoma multiforme. The main requirement for this therapy is selective targeting of tumor cells by sufficient quantities of10B atoms required for their capture/irradiation with low-energy thermal neutrons. The low content of boron targeting species in glioblastoma multiforme accounts for the difficulty in selective targeting of this very malignant cerebral tumor by this radiation modality. In the present study, we have used for the first time boron nitride nanotubes as carriers of boron atoms to overcome this problem and enhance the selective targeting and ablative efficacy of BNCT for these tumors. Following their dispersion in aqueous solution by noncovalent coating with biocompatible poly-l-lysine solutions, boron nitride nanotubes were functionalized with a fluorescent probe (quantum dots to enable their tracking and with folic acid as selective tumor targeting ligand. Initial in vitro studies have confirmed substantive and selective uptake of these nanovectors by glioblastoma multiforme cells, an observation which confirms their potential clinical application for BNCT therapy for these malignant cerebral tumors.

  7. From Abstract Art to Abstracted Artists

    Directory of Open Access Journals (Sweden)

    Romi Mikulinsky

    2016-11-01

    Full Text Available What lineage connects early abstract films and machine-generated YouTube videos? Hans Richter’s famous piece Rhythmus 21 is considered to be the first abstract film in the experimental tradition. The Webdriver Torso YouTube channel is composed of hundreds of thousands of machine-generated test patterns designed to check frequency signals on YouTube. This article discusses geometric abstraction vis-à-vis new vision, conceptual art and algorithmic art. It argues that the Webdriver Torso is an artistic marvel indicative of a form we call mathematical abstraction, which is art performed by computers and, quite possibly, for computers.

  8. Programme and abstracts

    International Nuclear Information System (INIS)

    1975-01-01

    Abstracts of 25 papers presented at the congress are given. The abstracts cover various topics including radiotherapy, radiopharmaceuticals, radioimmunoassay, health physics, radiation protection and nuclear medicine

  9. Mg-doping experiment and electrical transport measurement of boron nanobelts

    International Nuclear Information System (INIS)

    Kirihara, K.; Hyodo, H.; Fujihisa, H.; Wang, Z.; Kawaguchi, K.; Shimizu, Y.; Sasaki, T.; Koshizaki, N.; Soga, K.; Kimura, K.

    2006-01-01

    We measured electrical conductance of single crystalline boron nanobelts having α-tetragonal crystalline structure. The doping experiment of Mg was carried out by vapor diffusion method. The pure boron nanobelt is a p-type semiconductor and its electrical conductivity was estimated to be on the order of 10 -3 (Ω cm) -1 at room temperature. The carrier mobility of pure boron nanobelt was measured to be on the order of 10 -3 (cm 2 Vs -1 ) at room temperature and has an activation energy of ∼0.19 eV. The Mg-doped boron nanobelts have the same α-tetragonal crystalline structure as the pristine nanobelts. After Mg vapor diffusion, the nanobelts were still semiconductor, while the electrical conductance increased by a factor of 100-500. Transition to metal or superconductor by doping was not observed. - Graphical abstract: SEM micrographs of boron nanobelt after Ni/Au electrode fabrication by electron beam lithography. Display Omitted

  10. Enhanced oxidation resistance of carbon fiber reinforced lithium aluminosilicate composites by boron doping

    International Nuclear Information System (INIS)

    Xia, Long; Jin, Feng; Zhang, Tao; Hu, Xueting; Wu, Songsong; Wen, Guangwu

    2015-01-01

    Highlights: • C f /LAS composites exhibit enhanced oxidation resistance by boron doping. • Boron doping is beneficial to the improvement of graphitization degree of carbon fibers. • Graphitization of carbon fibers together with the decrease of viscosity of LAS matrix is responsible to the enhancement of oxidation resistance of C f /LAS composites. - Abstract: Carbon fiber reinforced lithium aluminosilicate matrix composites (C f /LAS) modified with boron doping were fabricated and oxidized for 1 h in static air. Weight loss, residual strength and microstructure were analyzed. The results indicate that boron doping has a remarkable effect on improving the oxidation resistance for C f /LAS. The synergism of low viscosity of LAS matrix at high temperature and formation of graphite crystals on the surface of carbon fibers, is responsible for excellent oxidation resistance of the boron doped C f /LAS.

  11. New Carbonate Standard Reference Materials for Boron Isotope Geochemistry

    Science.gov (United States)

    Stewart, J.; Christopher, S. J.; Day, R. D.

    2015-12-01

    The isotopic composition of boron (δ11B) in marine carbonates is well established as a proxy for past ocean pH. Yet, before palaeoceanographic interpretation can be made, rigorous assessment of analytical uncertainty of δ11B data is required; particularly in light of recent interlaboratory comparison studies that reported significant measurement disagreement between laboratories [1]. Well characterised boron standard reference materials (SRMs) in a carbonate matrix are needed to assess the accuracy and precision of carbonate δ11B measurements throughout the entire procedural chemistry; from sample cleaning, to ionic separation of boron from the carbonate matrix, and final δ11B measurement by multi-collector inductively coupled plasma mass spectrometry. To date only two carbonate reference materials exist that have been value-assigned by the boron isotope measurement community [2]; JCp-1 (porites coral) and JCt-1 (Giant Clam) [3]. The National Institute of Standards and Technology (NIST) will supplement these existing standards with new solution based inorganic carbonate boron SRMs that replicate typical foraminiferal and coral B/Ca ratios and δ11B values. These new SRMs will not only ensure quality control of full procedural chemistry between laboratories, but have the added benefits of being both in abundant supply and free from any restrictions associated with shipment of biogenic samples derived from protected species. Here we present in-house δ11B measurements of these new boron carbonate SRM solutions. These preliminary data will feed into an interlaboratory comparison study to establish certified values for these new NIST SRMs. 1. Foster, G.L., et al., Chemical Geology, 2013. 358(0): p. 1-14. 2. Gutjahr, M., et al., Boron Isotope Intercomparison Project (BIIP): Development of a new carbonate standard for stable isotopic analyses. Geophysical Research Abstracts, EGU General Assembly 2014, 2014. 16(EGU2014-5028-1). 3. Inoue, M., et al., Geostandards and

  12. Boron supplementation in broiler diets

    Directory of Open Access Journals (Sweden)

    EJ Fassani

    2004-12-01

    Full Text Available Boron supplementation in broiler feed is not a routine practice. However, some reports suggest a positive effect of boron on performance. This study assessed the effects of boron supplementation on broiler performance. Diets were based on maize and soybean meal, using boric acid P.A. as boron source. Six supplementation levels (0, 30, 60, 90, 120 and 150 ppm were evaluated using 1,440 one-day old males housed at a density of 30 chickens in each of 48 experimental plots of 3m². A completely randomized block design was used with 8 replicates. Feed intake, weight gain and feed conversion were assessed in the periods from 1 to 7 days, 1 to 21 days and 1 to 42 days of age, and viability was evaluated for the total 42-day rearing period. No performance variable was affected by boron supplementation (p>0.05 in the period from 1 to 7 days. The regression analysis indicated an ideal level of 37.4 ppm of boron for weight gain from 1 to 21 days (p0.05, although feed intake was reduced linearly with increased boron levels (p0.05. Ash and calcium percentages in the tibias of broilers and viability in the total rearing period were not affected by boron supplementation (p>0.05.

  13. The effect of the boron source composition ratio on the adsorption performance of hexagonal boron nitride without a template

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Ning, E-mail: zhangning5832@163.com; Zhang, Tong; Kan, Hongmin; Wang, Xiaoyang; Long, Haibo; Cui, Xingyu

    2015-08-01

    An inexpensive boric acid (H{sub 3}BO{sub 3}) and borax (Na{sub 2}B{sub 4}O{sub 7}·10H{sub 2}O) mix was used as a source of boron with different composition ratios, and urea was used as a nitrogen source, in flowing ammonia atmosphere, for the preparation of hexagonal boron nitride (h-BN) with different micro-morphologies. Under a certain synthesis process, the effects of the molar ratio of borax and boric acid (or simply the boron source composition ratio for short) on the phase composition of the sample were studied; the work also explored the effect of boron source composition ratio on the micro-morphology, adsorption desorption isotherm and specific surface area of the h-BN powder. The main purpose of this work was to determine the optimum composition ratio of preparing spherical mesoporous h-BN and ensure that the micro-mechanism underpinning the formation of spherical mesoporous h-BN was understood. The results showed that at the optimum boron source composition ratio of 1:1, globular mesoporous spheres with a diameter of approximately 600–800 nm could be obtained with the highest pore volume and specific surface area (230.2 m{sup 2}/g). - Graphical abstract: Display Omitted - Highlights: • Spherical h-BN was synthesized by controlling the boron source composition ratio. • Without extra spherical template, solid Na{sub 2}O was equal to a spherical template. • At boron source composition ratio of 1:1, h-BN had best adsorption performance.

  14. Boron atom reactions

    International Nuclear Information System (INIS)

    Estes, R.; Tabacco, M.B.; Digiuseppe, T.G.; Davidovits, P.

    1982-01-01

    The reaction rates of atomic boron with various epoxides have been measured in a flow tube apparatus. The bimolecular rate constants, in units of cm 3 molecule -1 s -1 , are: 1,2-epoxypropane (8.6 x 10 -11 ), 1,2-epoxybutane (8.8 x 10 -11 ), 1,2,3,4-diepoxybutane (5.5 x 10 -11 ), 1-chloro-2,3-epoxypropane (5.7 x 10 -11 ), and 1,2-epoxy-3,3,3-trichloropropane (1.5 x 10 -11 ). (orig.)

  15. Separation process for boron isotopes

    Energy Technology Data Exchange (ETDEWEB)

    Rockwood, S D

    1975-06-12

    The method according to the invention is characterized by the steps of preparing a gaseous mixture of BCl/sub 3/ containing the isotopes of boron and oxygen as the extractor, irradiating that mixture in the tube of the separator device by means of P- or R-lines of a CO/sub 2/ laser for exciting the molecules containing a given isotope of boron, simultaneously irradiating the mixture with UV for photodissociating the excited BCl/sub 3/ molecules and separating BCl/sub 3/ from the reaction products of photodissociation and from oxygen. Such method is suitable for preparing boron used in nuclear reactors.

  16. Lattice dynamics of α boron and of boron carbide

    International Nuclear Information System (INIS)

    Vast, N.

    1999-01-01

    The atomic structure and the lattice dynamics of α boron and of B 4 C boron carbide have been studied by Density Functional Theory (D.F.T.) and Density Functional Perturbation Theory (D.F.P.T.). The bulk moduli of the unit-cell and of the icosahedron have been investigated, and the equation of state at zero temperature has been determined. In α boron, Raman diffusion and infrared absorption have been studied under pressure, and the theoretical and experimental Grueneisen coefficients have been compared. In boron carbide, inspection of the theoretical and experimental vibrational spectra has led to the determination of the atomic structure of B 4 C. Finally, the effects of isotopic disorder have been modeled by an exact method beyond the mean-field approximation, and the effects onto the Raman lines has been investigated. The method has been applied to isotopic alloys of diamond and germanium. (author)

  17. Nothing Boring About Boron

    Science.gov (United States)

    Pizzorno, Lara

    2015-01-01

    The trace mineral boron is a micronutrient with diverse and vitally important roles in metabolism that render it necessary for plant, animal, and human health, and as recent research suggests, possibly for the evolution of life on Earth. As the current article shows, boron has been proven to be an important trace mineral because it (1) is essential for the growth and maintenance of bone; (2) greatly improves wound healing; (3) beneficially impacts the body’s use of estrogen, testosterone, and vitamin D; (4) boosts magnesium absorption; (5) reduces levels of inflammatory biomarkers, such as high-sensitivity C-reactive protein (hs-CRP) and tumor necrosis factor α (TNF-α); (6) raises levels of antioxidant enzymes, such as superoxide dismutase (SOD), catalase, and glutathione peroxidase; (7) protects against pesticide-induced oxidative stress and heavy-metal toxicity; (8) improves the brains electrical activity, cognitive performance, and short-term memory for elders; (9) influences the formation and activity of key biomolecules, such as S-adenosyl methionine (SAM-e) and nicotinamide adenine dinucleotide (NAD+); (10) has demonstrated preventive and therapeutic effects in a number of cancers, such as prostate, cervical, and lung cancers, and multiple and non-Hodgkin’s lymphoma; and (11) may help ameliorate the adverse effects of traditional chemotherapeutic agents. In none of the numerous studies conducted to date, however, do boron’s beneficial effects appear at intakes > 3 mg/d. No estimated average requirements (EARs) or dietary reference intakes (DRIs) have been set for boron—only an upper intake level (UL) of 20 mg/d for individuals aged ≥ 18 y. The absence of studies showing harm in conjunction with the substantial number of articles showing benefits support the consideration of boron supplementation of 3 mg/d for any individual who is consuming a diet lacking in fruits and vegetables or who is at risk for or has osteopenia; osteoporosis

  18. Program and abstracts

    International Nuclear Information System (INIS)

    1975-01-01

    Abstracts of the papers given at the conference are presented. The abstracts are arranged under sessions entitled:Theoretical Physics; Nuclear Physics; Solid State Physics; Spectroscopy; Physics Education; SANCGASS; Astronomy; Plasma Physics; Physics in Industry; Applied and General Physics

  19. Program and abstracts

    Energy Technology Data Exchange (ETDEWEB)

    1975-01-01

    Abstracts of the papers given at the conference are presented. The abstracts are arranged under sessions entitled:Theoretical Physics; Nuclear Physics; Solid State Physics; Spectroscopy; Physics Education; SANCGASS; Astronomy; Plasma Physics; Physics in Industry; Applied and General Physics.

  20. Introduction to abstract algebra

    CERN Document Server

    Nicholson, W Keith

    2012-01-01

    Praise for the Third Edition ". . . an expository masterpiece of the highest didactic value that has gained additional attractivity through the various improvements . . ."-Zentralblatt MATH The Fourth Edition of Introduction to Abstract Algebra continues to provide an accessible approach to the basic structures of abstract algebra: groups, rings, and fields. The book's unique presentation helps readers advance to abstract theory by presenting concrete examples of induction, number theory, integers modulo n, and permutations before the abstract structures are defined. Readers can immediately be

  1. Abstracting Concepts and Methods.

    Science.gov (United States)

    Borko, Harold; Bernier, Charles L.

    This text provides a complete discussion of abstracts--their history, production, organization, publication--and of indexing. Instructions for abstracting are outlined, and standards and criteria for abstracting are stated. Management, automation, and personnel are discussed in terms of possible economies that can be derived from the introduction…

  2. Boronization in TEXTOR

    International Nuclear Information System (INIS)

    Winter, J.; Esser, H.G.; Koenen, L.; Reimer, H.; Seggern, J. v.; Schlueter, J.; Waelbroeck, F.; Wienhold, P.; Veprek, S.

    1989-01-01

    The liner and limiters of TEXTOR have been coated in situ with a boron containing carbon film using a RG discharge in a throughflow of 0.8 He + 0.1 B 2 H 6 + 0.1 CH 4 . The average film thickness was 30-50 nm, the ratio of boron and carbon in the layer was about 1:1 according to Auger Electron Spectroscopy. Subsequent tokamak discharges are characterized by a small fraction of radiated power ( eff lower than 1.2 are derived from conductivity measurements. The most prominent change in the impurity concentration compared to good conditions in a carbonized surrounding is measured for oxygen. The value OVI/anti n e of the OVI intensity normalized to the averaged plasma density anti n e decreases by more than a factor of four. The decrease in the oxygen content manifests itself also as a reduction of the CO and CO 2 partial pressures measured during and after the discharge with a sniffer probe. The carbon levels are reduced by a factor of about two as measured by the normalized intensity CII/anti n e of the CII line and via the ratio of the C fluxes and deuterium fluxed measured at the limiter (CI/D α ). The wall shows a pronounced sorption of hydrogen from the plasma, easing the density control and the establishment of low recycling conditions. The beneficial conditions did not show a significant deterioration during more than 200 discharges, including numerous shots at ICRH power levels >2 MW. (orig.)

  3. Note on boron toxicity in oats

    Energy Technology Data Exchange (ETDEWEB)

    Langille, W M; Mahoney, J F

    1959-01-01

    Boron was applied at the rate of 35 pounds per acre of borax to a field of oats. With the first noticeable growth there appeared a definite chlorotic condition of the oat seedlings on plots receiving boron treatments. Analysis of chlorotic tissue at 3 weeks after seeding indicated 110 ppm boron, while apparently healthy tissue contained 6.1 ppm boron at the same stage of growth. There was a rapid decline in the boron content of the oat tissue as the crop grew older. At maturity the oat tissue from the boron-treated plots contained an average of 14.15 ppm boron as compared with 4.10 boron from untreated areas. Boron toxicity had no harmful effect so far as yields were concerned, under the conditions of this experiment. 3 references.

  4. Method for producing polycrystalline boron nitride

    International Nuclear Information System (INIS)

    Alexeevskii, V.P.; Bochko, A.V.; Dzhamarov, S.S.; Karpinos, D.M.; Karyuk, G.G.; Kolomiets, I.P.; Kurdyumov, A.V.; Pivovarov, M.S.; Frantsevich, I.N.; Yarosh, V.V.

    1975-01-01

    A mixture containing less than 50 percent of graphite-like boron nitride treated by a shock wave and highly defective wurtzite-like boron nitride obtained by a shock-wave method is compressed and heated at pressure and temperature values corresponding to the region of the phase diagram for boron nitride defined by the graphite-like compact modifications of boron nitride equilibrium line and the cubic wurtzite-like boron nitride equilibrium line. The resulting crystals of boron nitride exhibit a structure of wurtzite-like boron nitride or of both wurtzite-like and cubic boron nitride. The resulting material exhibits higher plasticity as compared with polycrystalline cubic boron nitride. Tools made of this compact polycrystalline material have a longer service life under impact loads in machining hardened steel and chilled iron. (U.S.)

  5. Metal interactions with boron clusters

    International Nuclear Information System (INIS)

    Grimes, R.N.

    1982-01-01

    This book presents information on the following topics: the structural and bonding features of metallaboranes and metallacarboranes; transition-metal derivatives of nido-boranes and some related species; interactions of metal groups with the octahydrotriborate (1-) anion, B 3 H 8 ; metallaboron cage compounds of the main group metals; closo-carborane-metal complexes containing metal-carbon and metal-boron omega-bonds; electrochemistry of metallaboron cage compounds; and boron clusters with transition metal-hydrogen bonds

  6. Building America

    Energy Technology Data Exchange (ETDEWEB)

    Brad Oberg

    2010-12-31

    IBACOS researched the constructability and viability issues of using high performance windows as one component of a larger approach to building houses that achieve the Building America 70% energy savings target.

  7. 2018 Congress Poster Abstracts

    Science.gov (United States)

    2018-02-21

    Each abstract has been indexed according to the first author. Abstracts appear as they were submitted and have not undergone editing or the Oncology Nursing Forum’s review process. Only abstracts that will be presented appear here. Poster numbers are subject to change. For updated poster numbers, visit congress.ons.org or check the Congress guide. Data published in abstracts presented at the ONS 43rd Annual Congress are embargoed until the conclusion of the presentation. Coverage and/or distribution of an abstract, poster, or any of its supplemental material to or by the news media, any commercial entity, or individuals, including the authors of said abstract, is strictly prohibited until the embargo is lifted. Promotion of general topics and speakers is encouraged within these guidelines.

  8. 2018 Congress Podium Abstracts

    Science.gov (United States)

    2018-02-21

    Each abstract has been indexed according to first author. Abstracts appear as they were submitted and have not undergone editing or the Oncology Nursing Forum’s review process. Only abstracts that will be presented appear here. For Congress scheduling information, visit congress.ons.org or check the Congress guide. Data published in abstracts presented at the ONS 43rd Annual Congress are embargoed until the conclusion of the presentation. Coverage and/or distribution of an abstract, poster, or any of its supplemental material to or by the news media, any commercial entity, or individuals, including the authors of said abstract, is strictly prohibited until the embargo is lifted. Promotion of general topics and speakers is encouraged within these guidelines.

  9. Magnetostriction of the polycrystalline Fe80Al20 alloy doped with boron

    International Nuclear Information System (INIS)

    Bormio-Nunes, Cristina; Teodoro dos Santos, Claudio; Botani de Souza Dias, Mateus; Doerr, Mathias; Granovsky, Sergey; Loewenhaupt, Michael

    2012-01-01

    Highlights: ► Fe 80 Al 20 polycrystalline alloy magnetostriction 40 ppm increased to 80 ppm due to 2% of B doping. ► B stabilizes α-FeAl phase and a coexistence of α-FeAl + Fe 3 Al improves magnetostriction. ► Presence of Fe 2 B phase causes domain rearrangement revealed by the decrease of the volume magnetostriction. - Abstract: The doping of Fe 80 Al 20 polycrystalline alloy with 2% of boron increased the total magnetostriction twofold compared to a sample without boron. A value close to 80 ppm was achieved at 300 K. The microstructures of the boron-doped alloys show a dendritically solidified matrix with interdendritic α-FeAl and/or Fe 3 Al and Fe 2 B eutectic between the grains. The XRD analysis reveals an increase in the volume fraction of α-FeAl and a correspondent decrease of the Fe 3 Al phase volume fraction as the boron content increases. The increase of the volume fraction of this tetragonal Fe 2 B phase in the samples doped with boron causes the decrease of the strong volume magnetostriction that was observed in the alloy without boron. There is some evidence that the improvement of the magnetostriction magnitude due to the addition of boron to the Fe 80 Al 20 alloy could reach the maximal magnetostriction if the 1:1 optimal ratio of the volume fractions of the α-FeAl and Fe 3 Al phases could be reached.

  10. Influence of boron on strain hardening behaviour and ductility of low carbon hot rolled steel

    International Nuclear Information System (INIS)

    Deva, Anjana; Jha, B.K.; Mishra, N.S.

    2011-01-01

    Highlights: → Unique feature of low strain hardening exponent (n) with high total elongation has been discussed in industrially produced low carbon boron containing steel. → n has been correlated with the micro structural changes occurring during deformation of steel. → This feature of low n and high % elongation has potential for higher cold reducibility. → The work is being reported for the first time on industrially produced low carbon boron containing steel. - Abstract: The beneficial effect of boron on mechanical properties of low carbon Al-killed steel has been reported in recent past. However, the effect of boron on strain hardening exponent (n) and ductility has not been fully understood. This aspect has been discussed in present work. The results of mill trials with reference to n and ductility with boron added steel are compared to those for commercial grade. The lowering of 'n' with increased total elongation in boron bearing steel has been related to the microstructural evolution as a result of boron addition.

  11. Compilation of Theses Abstracts

    National Research Council Canada - National Science Library

    2005-01-01

    This publication contains unclassified/unrestricted abstracts of classified or restricted theses submitted for the degrees of Doctor of Philosophy, Master of Business Administration, Master of Science...

  12. Nuclear medicine. Abstracts; Nuklearmedizin 2000. Abstracts

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    2000-07-01

    This issue of the journal contains the abstracts of the 183 conference papers as well as 266 posters presented at the conference. Subject fields covered are: Neurology, psychology, oncology, pediatrics, radiopharmacy, endocrinology, EDP, measuring equipment and methods, radiological protection, cardiology, and therapy. (orig./CB) [German] Die vorliegende Zeitschrift enthaelt die Kurzfassungen der 183 auf der Tagung gehaltenen Vortraege sowie der 226 praesentierten Poster, die sich mit den folgenden Themen befassten: Neurologie, Psychiatrie, Onkologie, Paediatrie, Radiopharmazie, Endokrinologie, EDV, Messtechnik, Strahlenschutz, Kardiologie sowie Therapie. (MG)

  13. Data Abstraction in GLISP.

    Science.gov (United States)

    Novak, Gordon S., Jr.

    GLISP is a high-level computer language (based on Lisp and including Lisp as a sublanguage) which is compiled into Lisp. GLISP programs are compiled relative to a knowledge base of object descriptions, a form of abstract datatypes. A primary goal of the use of abstract datatypes in GLISP is to allow program code to be written in terms of objects,…

  14. Truthful Monadic Abstractions

    DEFF Research Database (Denmark)

    Brock-Nannestad, Taus; Schürmann, Carsten

    2012-01-01

    indefinitely, finding neither a proof nor a disproof of a given subgoal. In this paper we characterize a family of truth-preserving abstractions from intuitionistic first-order logic to the monadic fragment of classical first-order logic. Because they are truthful, these abstractions can be used to disprove...

  15. Program and abstracts

    International Nuclear Information System (INIS)

    1976-01-01

    Abstracts of the papers given at the conference are presented. The abstracts are arranged under sessions entitled: Theoretical Physics; Nuclear Physics; Solid State Physics; Spectroscopy; Plasma Physics; Solar-Terrestrial Physics; Astrophysics and Astronomy; Radioastronomy; General Physics; Applied Physics; Industrial Physics

  16. Completeness of Lyapunov Abstraction

    Directory of Open Access Journals (Sweden)

    Rafael Wisniewski

    2013-08-01

    Full Text Available In this work, we continue our study on discrete abstractions of dynamical systems. To this end, we use a family of partitioning functions to generate an abstraction. The intersection of sub-level sets of the partitioning functions defines cells, which are regarded as discrete objects. The union of cells makes up the state space of the dynamical systems. Our construction gives rise to a combinatorial object - a timed automaton. We examine sound and complete abstractions. An abstraction is said to be sound when the flow of the time automata covers the flow lines of the dynamical systems. If the dynamics of the dynamical system and the time automaton are equivalent, the abstraction is complete. The commonly accepted paradigm for partitioning functions is that they ought to be transversal to the studied vector field. We show that there is no complete partitioning with transversal functions, even for particular dynamical systems whose critical sets are isolated critical points. Therefore, we allow the directional derivative along the vector field to be non-positive in this work. This considerably complicates the abstraction technique. For understanding dynamical systems, it is vital to study stable and unstable manifolds and their intersections. These objects appear naturally in this work. Indeed, we show that for an abstraction to be complete, the set of critical points of an abstraction function shall contain either the stable or unstable manifold of the dynamical system.

  17. The deleuzian abstract machines

    DEFF Research Database (Denmark)

    Werner Petersen, Erik

    2005-01-01

    To most people the concept of abstract machines is connected to the name of Alan Turing and the development of the modern computer. The Turing machine is universal, axiomatic and symbolic (E.g. operating on symbols). Inspired by Foucault, Deleuze and Guattari extended the concept of abstract...

  18. Check Sample Abstracts.

    Science.gov (United States)

    Alter, David; Grenache, David G; Bosler, David S; Karcher, Raymond E; Nichols, James; Rajadhyaksha, Aparna; Camelo-Piragua, Sandra; Rauch, Carol; Huddleston, Brent J; Frank, Elizabeth L; Sluss, Patrick M; Lewandrowski, Kent; Eichhorn, John H; Hall, Janet E; Rahman, Saud S; McPherson, Richard A; Kiechle, Frederick L; Hammett-Stabler, Catherine; Pierce, Kristin A; Kloehn, Erica A; Thomas, Patricia A; Walts, Ann E; Madan, Rashna; Schlesinger, Kathie; Nawgiri, Ranjana; Bhutani, Manoop; Kanber, Yonca; Abati, Andrea; Atkins, Kristen A; Farrar, Robert; Gopez, Evelyn Valencerina; Jhala, Darshana; Griffin, Sonya; Jhala, Khushboo; Jhala, Nirag; Bentz, Joel S; Emerson, Lyska; Chadwick, Barbara E; Barroeta, Julieta E; Baloch, Zubair W; Collins, Brian T; Middleton, Owen L; Davis, Gregory G; Haden-Pinneri, Kathryn; Chu, Albert Y; Keylock, Joren B; Ramoso, Robert; Thoene, Cynthia A; Stewart, Donna; Pierce, Arand; Barry, Michelle; Aljinovic, Nika; Gardner, David L; Barry, Michelle; Shields, Lisa B E; Arnold, Jack; Stewart, Donna; Martin, Erica L; Rakow, Rex J; Paddock, Christopher; Zaki, Sherif R; Prahlow, Joseph A; Stewart, Donna; Shields, Lisa B E; Rolf, Cristin M; Falzon, Andrew L; Hudacki, Rachel; Mazzella, Fermina M; Bethel, Melissa; Zarrin-Khameh, Neda; Gresik, M Vicky; Gill, Ryan; Karlon, William; Etzell, Joan; Deftos, Michael; Karlon, William J; Etzell, Joan E; Wang, Endi; Lu, Chuanyi M; Manion, Elizabeth; Rosenthal, Nancy; Wang, Endi; Lu, Chuanyi M; Tang, Patrick; Petric, Martin; Schade, Andrew E; Hall, Geraldine S; Oethinger, Margret; Hall, Geraldine; Picton, Avis R; Hoang, Linda; Imperial, Miguel Ranoa; Kibsey, Pamela; Waites, Ken; Duffy, Lynn; Hall, Geraldine S; Salangsang, Jo-Anne M; Bravo, Lulette Tricia C; Oethinger, Margaret D; Veras, Emanuela; Silva, Elvia; Vicens, Jimena; Silva, Elvio; Keylock, Joren; Hempel, James; Rushing, Elizabeth; Posligua, Lorena E; Deavers, Michael T; Nash, Jason W; Basturk, Olca; Perle, Mary Ann; Greco, Alba; Lee, Peng; Maru, Dipen; Weydert, Jamie Allen; Stevens, Todd M; Brownlee, Noel A; Kemper, April E; Williams, H James; Oliverio, Brock J; Al-Agha, Osama M; Eskue, Kyle L; Newlands, Shawn D; Eltorky, Mahmoud A; Puri, Puja K; Royer, Michael C; Rush, Walter L; Tavora, Fabio; Galvin, Jeffrey R; Franks, Teri J; Carter, James Elliot; Kahn, Andrea Graciela; Lozada Muñoz, Luis R; Houghton, Dan; Land, Kevin J; Nester, Theresa; Gildea, Jacob; Lefkowitz, Jerry; Lacount, Rachel A; Thompson, Hannis W; Refaai, Majed A; Quillen, Karen; Lopez, Ana Ortega; Goldfinger, Dennis; Muram, Talia; Thompson, Hannis

    2009-02-01

    The following abstracts are compiled from Check Sample exercises published in 2008. These peer-reviewed case studies assist laboratory professionals with continuing medical education and are developed in the areas of clinical chemistry, cytopathology, forensic pathology, hematology, microbiology, surgical pathology, and transfusion medicine. Abstracts for all exercises published in the program will appear annually in AJCP.

  19. Adsorption of boron from boron-containing wastewaters by ion exchange in a continuous reactor

    International Nuclear Information System (INIS)

    Yilmaz, A. Erdem; Boncukcuoglu, Recep; Yilmaz, M. Tolga; Kocakerim, M. Muhtar

    2005-01-01

    In this study, boron removal from boron-containing wastewaters prepared synthetically was investigated. The experiments in which Amberlite IRA 743, boron specific resin was used were carried out in a column reactor. The bed volume of resin, boron concentration, flow rate and temperature were selected as experimental parameters. The experimental results showed that percent of boron removal increased with increasing amount of resin and with decreasing boron concentration in the solution. Boron removal decreased with increasing of flow rate and the effect of temperature on the percent of total boron removal increased the boron removal rate. As a result, it was seen that about 99% of boron in the wastewater could be removed at optimum conditions

  20. Abstract Datatypes in PVS

    Science.gov (United States)

    Owre, Sam; Shankar, Natarajan

    1997-01-01

    PVS (Prototype Verification System) is a general-purpose environment for developing specifications and proofs. This document deals primarily with the abstract datatype mechanism in PVS which generates theories containing axioms and definitions for a class of recursive datatypes. The concepts underlying the abstract datatype mechanism are illustrated using ordered binary trees as an example. Binary trees are described by a PVS abstract datatype that is parametric in its value type. The type of ordered binary trees is then presented as a subtype of binary trees where the ordering relation is also taken as a parameter. We define the operations of inserting an element into, and searching for an element in an ordered binary tree; the bulk of the report is devoted to PVS proofs of some useful properties of these operations. These proofs illustrate various approaches to proving properties of abstract datatype operations. They also describe the built-in capabilities of the PVS proof checker for simplifying abstract datatype expressions.

  1. Lattice vibrations in α-boron

    International Nuclear Information System (INIS)

    Richter, W.

    1976-01-01

    α-rhombohedral boron is the simplest boron modification, with only 12 atoms per unit cell. The boron atoms are arranged in B 12 icosahedra, which are centered at the lattice points of a primitive rhombohedral lattice. The icosahedra are slightly deformed, as the five-fold symmetry of the ideal icosahedron is incompatible with any crystal structure. The lattice dynamics of α-boron are discussed in terms of the model developed by Weber and Thorpe. (Auth.)

  2. Study of the boron levels in serum after implantation of different ratios nano-hexagonal boron nitride–hydroxy apatite in rat femurs

    Energy Technology Data Exchange (ETDEWEB)

    Atila, Alptug, E-mail: alptugatila@yahoo.com [Department of Analytical Chemistry, Faculty of Pharmacy, Ataturk University, Erzurum 25240 (Turkey); Halici, Zekai; Cadirci, Elif [Department of Pharmacology, Faculty of Medicine, Ataturk University, Erzurum 25240 (Turkey); Karakus, Emre [Department of Pharmacology and Toxicology, School of Veterinary Medicine, Ataturk University, Erzurum 25240 (Turkey); Palabiyik, Saziye Sezin [Department of Pharmaceutical Toxicology, Faculty of Pharmacy, Ataturk University, Erzurum 25240 (Turkey); Ay, Nuran [Department of Material Science and Engineering, Faculty of Engineering, Anadolu University, Eskisehir 26555 (Turkey); Bakan, Feray [Sabancı University Nanotechnology Research and Application Center (SUNUM), Istanbul 34956 (Turkey); Yilmaz, Sahin [Department of Genetics and Bioengineering, Faculty of Engineering and Architecture, Yeditepe University, Istanbul 34755 (Turkey)

    2016-01-01

    ABSTRACT: Boron and its derivatives are effective in bone recovery and osteointegration. However, increasing the boron levels in body liquids may cause toxicity. The aim of our study is to investigate serum boron levels using ICP-MS after implantation of different ratios of nano-hBN–HA composites in rat femurs. All rats were (n = 126) divided into five experimental groups (n = 24) and one healthy group (6 rats); healthy (Group1), femoral defect + %100HA (Group2), femoral defect + %2.5hBN + %97.5HA (Group3), femoral defect + %5hBN + %95HA (Group4), femoral defect + %10hBN + %90 HA (Group5), femoral defect + %100hBN (Group6). The femoral defect was created in the distal femur (3 mm drill-bit). Each implant group was divided into four different groups (n = 24) also 6 rats sacrificed for each groups in one week intervals during four weeks. In our results; at 1, 2, 3, and 4 weeks after implantation near bone tissue, serum levels of boron were evaluated using ICP-MS. We demonstrated that neither short-term nor long-term implantation of hBN–HA composite resulted in statistically increased serum boron levels in experimental groups compared to healthy group. In conclusion, this study investigated the implant material produced form hBN–HA for the first time. Our data suggest that hBN is a new promising target for biomaterial and implant bioengineers. - Highlights: • Nano-hBN–HA composites are new targets for biomaterial and implant bioengineers. • Serum boron levels were researched after implantation of nano-hBN–HA composites. • Implantation of hBN–HA composite did not result in increased serum boron levels. • The use of boron in composite form with HA did not change the stability of the implant.

  3. Completeness of Lyapunov Abstraction

    DEFF Research Database (Denmark)

    Wisniewski, Rafal; Sloth, Christoffer

    2013-01-01

    the vector field, which allows the generation of a complete abstraction. To compute the functions that define the subdivision of the state space in an algorithm, we formulate a sum of squares optimization problem. This optimization problem finds the best subdivisioning functions, with respect to the ability......This paper addresses the generation of complete abstractions of polynomial dynamical systems by timed automata. For the proposed abstraction, the state space is divided into cells by sublevel sets of functions. We identify a relation between these functions and their directional derivatives along...

  4. Study the gas sensing properties of boron nitride nanosheets

    International Nuclear Information System (INIS)

    Sajjad, Muhammad; Feng, Peter

    2014-01-01

    Graphical abstract: - Highlights: • We synthesized boron nitride nanosheets (BNNSs) on silicon substrate. • We analyzed gas sensing properties of BNNSs-based gas-sensor device. • CH 4 gas is used to measure gas-sensing properties of the device. • Quick response and recovery time of the device is recorded. • BNNSs showed excellent sensitivity to the working gas. - Abstract: In the present communication, we report on the synthesis of boron nitride nanosheets (BNNSs) and study of their gas sensing properties. BNNSs are synthesized by irradiating pyrolytic hexagonal boron nitride (h-BN) target using CO 2 laser pulses. High resolution transmission electron microscopic measurements (HRTEM) revealed 2-dientional honeycomb crystal lattice structure of BNNSs. HRTEM, electron diffraction, XRD and Raman scattering measurements clearly identified h-BN. Gas sensing properties of synthesized BNNSs were analyzed with prototype gas sensor using methane as working gas. A systematic response curve of the sensor is recorded in each cycle of gas “in” and “out”; suggesting excellent sensitivity and high performance of BNNSs-based gas-sensor

  5. Polyethylene/boron-containing composites for radiation shielding

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Ji Wook [Center for Materials Architecturing, Institute for Multi-Disciplinary Convergence of Materials, Korea Institute of Science and Technology (KIST), Seoul 136-791 (Korea, Republic of); Department of Chemical and Biological Engineering, Korea University, Seoul 136-701 (Korea, Republic of); Lee, Jang-Woo; Yu, Seunggun; Baek, Bum Ki; Hong, Jun Pyo [Center for Materials Architecturing, Institute for Multi-Disciplinary Convergence of Materials, Korea Institute of Science and Technology (KIST), Seoul 136-791 (Korea, Republic of); Seo, Yongsok [School of Materials Science and Engineering, Seoul National University, Seoul 151-744 (Korea, Republic of); Kim, Woo Nyon [Department of Chemical and Biological Engineering, Korea University, Seoul 136-701 (Korea, Republic of); Hong, Soon Man, E-mail: smhong@kist.re.kr [Center for Materials Architecturing, Institute for Multi-Disciplinary Convergence of Materials, Korea Institute of Science and Technology (KIST), Seoul 136-791 (Korea, Republic of); Nanomaterials Science and Engineering, University of Science and Technology, Daejeon 305-350 (Korea, Republic of); Koo, Chong Min, E-mail: koo@kist.re.kr [Center for Materials Architecturing, Institute for Multi-Disciplinary Convergence of Materials, Korea Institute of Science and Technology (KIST), Seoul 136-791 (Korea, Republic of); Nanomaterials Science and Engineering, University of Science and Technology, Daejeon 305-350 (Korea, Republic of)

    2014-06-01

    Graphical abstract: - Highlights: • HDPE/silane-treated boron nitride (mBN) composites were fabricated. • The HDPE/mBN composites revealed a strong adhesion behavior at the interface of matrix/filler. • The HDPE/mBN composites show superior radiation shielding, thermoconductive and mechanical properties to the composites containing pristine BN and B{sub 4}C fillers. - Abstract: High-density polyethylene (HDPE) composites with modified boron nitride (mBN) fillers, functionalized with an organosilane, were fabricated through conventional melt-extrusion processing techniques. The properties and performances of these composites were compared with those of the composites containing pristine BN and boron carbide (B{sub 4}C) fillers. The silane functionalization of the BN fillers strongly improved the interfacial adhesion between the polymer matrix and the filler. As a result, the HDPE/mBN composites showed a better dispersion state of the filler particles, larger tensile modulus, greater effective thermal conductivity, and better neutron shielding property compared with the HDPE/BN and HDPE/B{sub 4}C composites.

  6. Polyethylene/boron-containing composites for radiation shielding

    International Nuclear Information System (INIS)

    Shin, Ji Wook; Lee, Jang-Woo; Yu, Seunggun; Baek, Bum Ki; Hong, Jun Pyo; Seo, Yongsok; Kim, Woo Nyon; Hong, Soon Man; Koo, Chong Min

    2014-01-01

    Graphical abstract: - Highlights: • HDPE/silane-treated boron nitride (mBN) composites were fabricated. • The HDPE/mBN composites revealed a strong adhesion behavior at the interface of matrix/filler. • The HDPE/mBN composites show superior radiation shielding, thermoconductive and mechanical properties to the composites containing pristine BN and B 4 C fillers. - Abstract: High-density polyethylene (HDPE) composites with modified boron nitride (mBN) fillers, functionalized with an organosilane, were fabricated through conventional melt-extrusion processing techniques. The properties and performances of these composites were compared with those of the composites containing pristine BN and boron carbide (B 4 C) fillers. The silane functionalization of the BN fillers strongly improved the interfacial adhesion between the polymer matrix and the filler. As a result, the HDPE/mBN composites showed a better dispersion state of the filler particles, larger tensile modulus, greater effective thermal conductivity, and better neutron shielding property compared with the HDPE/BN and HDPE/B 4 C composites

  7. New Icosahedral Boron Carbide Semiconductors

    Science.gov (United States)

    Echeverria Mora, Elena Maria

    Novel semiconductor boron carbide films and boron carbide films doped with aromatic compounds have been investigated and characterized. Most of these semiconductors were formed by plasma enhanced chemical vapor deposition. The aromatic compound additives used, in this thesis, were pyridine (Py), aniline, and diaminobenzene (DAB). As one of the key parameters for semiconducting device functionality is the metal contact and, therefore, the chemical interactions or band bending that may occur at the metal/semiconductor interface, X-ray photoemission spectroscopy has been used to investigate the interaction of gold (Au) with these novel boron carbide-based semiconductors. Both n- and p-type films have been tested and pure boron carbide devices are compared to those containing aromatic compounds. The results show that boron carbide seems to behave differently from other semiconductors, opening a way for new analysis and approaches in device's functionality. By studying the electrical and optical properties of these films, it has been found that samples containing the aromatic compound exhibit an improvement in the electron-hole separation and charge extraction, as well as a decrease in the band gap. The hole carrier lifetimes for each sample were extracted from the capacitance-voltage, C(V), and current-voltage, I(V), curves. Additionally, devices, with boron carbide with the addition of pyridine, exhibited better collection of neutron capture generated pulses at ZERO applied bias, compared to the pure boron carbide samples. This is consistent with the longer carrier lifetimes estimated for these films. The I-V curves, as a function of external magnetic field, of the pure boron carbide films and films containing DAB demonstrate that significant room temperature negative magneto-resistance (> 100% for pure samples, and > 50% for samples containing DAB) is possible in the resulting dielectric thin films. Inclusion of DAB is not essential for significant negative magneto

  8. Boron steel. I Part. Preparation

    International Nuclear Information System (INIS)

    Jaraiz Franco, E.; Esteban Hernandez, J. A.

    1960-01-01

    With the advent of the first nuclear reactors arise the need for control rods and shielding duties for some types of radiations. One of the materials used for this purpose has been the high boron steel. This paper describes the melting and casting procedures employed for the production, at laboratory scale, of steels with Boron content ranging from 1 to 4 per cent, as well as the metallographic and X-Ray techniques used for the identification of the present phases. The electrolytic technique employed for the isolation of the Fe 2 B phase and its subsequent X-Ray identification has proved to be satisfactory. (Author) 11 refs

  9. Chemical separation of boron isotopes

    Energy Technology Data Exchange (ETDEWEB)

    Palko, A.A.

    1978-06-01

    This is the final report of the research performed at ORNL on the chemical fractionation of boron isotopes between BF/sub 3/ gas and the liquid molecular addition compounds of BF/sub 3/. Thirty compounds were studied, ten of them in detail. Graphs and equations are given for variation of isotopic equilibrium constant, vapor pressure, and BF/sub 3/ solubility as a function of temperature. Rate of isotopic exchange and melting points were determined. Several of the compounds are likely candidates for use in a gas-liquid countercurrent exchange system for large-scale separation of boron isotopes. 23 figs, 53 tables, 39 references.

  10. Chemical separation of boron isotopes

    International Nuclear Information System (INIS)

    Palko, A.A.

    1978-06-01

    This is the final report of the research performed at ORNL on the chemical fractionation of boron isotopes between BF 3 gas and the liquid molecular addition compounds of BF 3 . Thirty compounds were studied, ten of them in detail. Graphs and equations are given for variation of isotopic equilibrium constant, vapor pressure, and BF 3 solubility as a function of temperature. Rate of isotopic exchange and melting points were determined. Several of the compounds are likely candidates for use in a gas-liquid countercurrent exchange system for large-scale separation of boron isotopes. 23 figs, 53 tables, 39 references

  11. Scientific meeting abstracts

    International Nuclear Information System (INIS)

    1999-01-01

    The document is a collection of the scientific meeting abstracts in the fields of nuclear physics, medical sciences, chemistry, agriculture, environment, engineering, different aspects of energy and presents research done in 1999 in these fields

  12. Science meeting. Abstracts

    International Nuclear Information System (INIS)

    2000-01-01

    the document is a collection of the science meeting abstracts in the fields of nuclear physics, medical sciences, chemistry, agriculture, environment, engineering, material sciences different aspects of energy and presents research done in 2000 in these fields

  13. Mathematical games, abstract games

    CERN Document Server

    Neto, Joao Pedro

    2013-01-01

    User-friendly, visually appealing collection offers both new and classic strategic board games. Includes abstract games for two and three players and mathematical games such as Nim and games on graphs.

  14. Textbook America.

    Science.gov (United States)

    Karp, Walter

    1980-01-01

    Focuses on how political attitudes have been influenced by American history textbooks at various times throughout history. Excerpts from traditional and revisionist textbooks are presented, with emphasis on "America Revised" by Frances FitzGerald. Journal available from Harper's Magazine Co., 2 Park Ave., New York, NY 10016. (DB)

  15. Abstracts of contributed papers

    Energy Technology Data Exchange (ETDEWEB)

    1994-08-01

    This volume contains 571 abstracts of contributed papers to be presented during the Twelfth US National Congress of Applied Mechanics. Abstracts are arranged in the order in which they fall in the program -- the main sessions are listed chronologically in the Table of Contents. The Author Index is in alphabetical order and lists each paper number (matching the schedule in the Final Program) with its corresponding page number in the book.

  16. Two-channel neutron boron meter

    International Nuclear Information System (INIS)

    Chen Yongqing; Yin Guowei; Chai Songshan; Deng Zhaoping; Zhou Bin

    1993-09-01

    The two-channel neutron boron meter is a continuous on-line measuring device to measure boron concentration of primary cooling liquid of reactors. The neutron-leakage-compensation method is taken in the measuring mechanism. In the primary measuring configuration, the mini-boron-water annulus and two-channel and central calibration loop are adopted. The calibration ring and constant-temperature of boron-water can be remotely controlled by secondary instruments. With the microcomputer data processing system the boron concentration is automatically measured and calibrated in on-line mode. The meter has many advantages such as high accuracy, fast response, multi-applications, high reliability and convenience

  17. Radiation shielding properties of high performance concrete reinforced with basalt fibers infused with natural and enriched boron

    Energy Technology Data Exchange (ETDEWEB)

    Zorla, Eyüp; Ipbüker, Cagatay [University of Tartu, Institute of Physics (Estonia); Biland, Alex [US Basalt Corp., Houston (United States); Kiisk, Madis [University of Tartu, Institute of Physics (Estonia); Kovaljov, Sergei [OÜ Basaltest, Tartu (Estonia); Tkaczyk, Alan H. [University of Tartu, Institute of Physics (Estonia); Gulik, Volodymyr, E-mail: volodymyr.gulik@gmail.com [Institute for Safety Problems of Nuclear Power Plants, Lysogirska 12, of. 201, 03028 Kyiv (Ukraine)

    2017-03-15

    Highlights: • Basalt fiber infused with natural and enriched boron in varying proportions. • Gamma-ray attenuation remains stable with addition of basalt-boron fiber. • Improvement in neutron shielding for nuclear facilities producing fast fission spectrum. • Basalt-boron fiber could decrease the shielding thickness in thermal spectrum reactors. - Abstract: The importance of radiation shielding is increasing in parallel with the expansion of the application areas of nuclear technologies. This study investigates the radiation shielding properties of two types of high strength concrete reinforced with basalt fibers infused with 12–20% boron oxide, containing varying fractions of natural and enriched boron. The gamma-ray shielding characteristics are analyzed with the help of the WinXCom, whereas the neutron shielding characteristics are modeled and computed by Monte Carlo Serpent code. For gamma-ray shielding, the attenuation coefficients of the studied samples do not display any significant variation due to the addition of basalt-boron fibers at any mixing proportion. For neutron shielding, the addition of basalt-boron fiber has negligible effects in the case of very fast neutrons (14 MeV), but it could considerably improve the neutron shielding of concrete for nuclear facilities producing a fast fission spectrum (e.g. with reactors as BN-800, FBTR) and thermal neutron spectrum (Light Water Reactors (LWR)). It was also found that basalt-boron fiber could decrease the thickness of radiation shielding material in thermal spectrum reactors.

  18. Radiation shielding properties of high performance concrete reinforced with basalt fibers infused with natural and enriched boron

    International Nuclear Information System (INIS)

    Zorla, Eyüp; Ipbüker, Cagatay; Biland, Alex; Kiisk, Madis; Kovaljov, Sergei; Tkaczyk, Alan H.; Gulik, Volodymyr

    2017-01-01

    Highlights: • Basalt fiber infused with natural and enriched boron in varying proportions. • Gamma-ray attenuation remains stable with addition of basalt-boron fiber. • Improvement in neutron shielding for nuclear facilities producing fast fission spectrum. • Basalt-boron fiber could decrease the shielding thickness in thermal spectrum reactors. - Abstract: The importance of radiation shielding is increasing in parallel with the expansion of the application areas of nuclear technologies. This study investigates the radiation shielding properties of two types of high strength concrete reinforced with basalt fibers infused with 12–20% boron oxide, containing varying fractions of natural and enriched boron. The gamma-ray shielding characteristics are analyzed with the help of the WinXCom, whereas the neutron shielding characteristics are modeled and computed by Monte Carlo Serpent code. For gamma-ray shielding, the attenuation coefficients of the studied samples do not display any significant variation due to the addition of basalt-boron fibers at any mixing proportion. For neutron shielding, the addition of basalt-boron fiber has negligible effects in the case of very fast neutrons (14 MeV), but it could considerably improve the neutron shielding of concrete for nuclear facilities producing a fast fission spectrum (e.g. with reactors as BN-800, FBTR) and thermal neutron spectrum (Light Water Reactors (LWR)). It was also found that basalt-boron fiber could decrease the thickness of radiation shielding material in thermal spectrum reactors.

  19. Toxicity evaluation of boron nitride nanospheres and water-soluble boron nitride in Caenorhabditis elegans

    Directory of Open Access Journals (Sweden)

    Wang N

    2017-08-01

    Full Text Available Ning Wang,1 Hui Wang,2 Chengchun Tang,3 Shijun Lei,1 Wanqing Shen,1 Cong Wang,1 Guobin Wang,4 Zheng Wang,1,4 Lin Wang1,5 1Research Center for Tissue Engineering and Regenerative Medicine, Union Hospital, 2Department of Medical Genetics, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 3Boron Nitride Research Center, School of Materials Science and Engineering, Hebei University of Technology, Tianjin, 4Department of Gastrointestinal Surgery, 5Department of Clinical Laboratory, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China Abstract: Boron nitride (BN nanomaterials have been increasingly explored for potential biological applications. However, their toxicity remains poorly understood. Using Caenorhabditis elegans as a whole-animal model for toxicity analysis of two representative types of BN nanomaterials – BN nanospheres (BNNSs and highly water-soluble BN nanomaterial (named BN-800-2 – we found that BNNSs overall toxicity was less than soluble BN-800-2 with irregular shapes. The concentration thresholds for BNNSs and BN-800-2 were 100 µg·mL-1 and 10 µg·mL-1, respectively. Above this concentration, both delayed growth, decreased life span, reduced progeny, retarded locomotion behavior, and changed the expression of phenotype-related genes to various extents. BNNSs and BN-800-2 increased oxidative stress levels in C. elegans by promoting reactive oxygen species production. Our results further showed that oxidative stress response and MAPK signaling-related genes, such as GAS1, SOD2, SOD3, MEK1, and PMK1, might be key factors for reactive oxygen species production and toxic responses to BNNSs and BN-800-2 exposure. Together, our results suggest that when concentrations are lower than 10 µg·mL-1, BNNSs are more biocompatible than BN-800-2 and are potentially biocompatible material. Keywords: boron nitride nanomaterials, Caenorhabditis elegans, nanotoxicology

  20. Boron-enhanced diffusion of boron from ultralow-energy boron implantation

    International Nuclear Information System (INIS)

    Agarwal, A.; Eaglesham, D.J.; Gossmann, H.J.; Pelaz, L.; Herner, S.B.; Jacobson, D.C.

    1998-01-01

    The authors have investigated the diffusion enhancement mechanism of BED (boron enhanced diffusion), wherein the boron diffusivity is enhanced three to four times over the equilibrium diffusivity at 1,050 C in the proximity of a silicon layer containing a high boron concentration. It is shown that BED is associated with the formation of a fine-grain polycrystalline silicon boride phase within an initially amorphous Si layer having a high B concentration. For 0.5 keV B + , the threshold implantation dose which leads to BED lies between 3 x 10 14 and of 1 x 10 15 /cm -2 . Formation of the shallowest possible junctions by 0.5 keV B + requires that the implant dose be kept lower than this threshold

  1. Green synthesis of boron doped graphene and its application as high performance anode material in Li ion battery

    Energy Technology Data Exchange (ETDEWEB)

    Sahoo, Madhumita; Sreena, K.P.; Vinayan, B.P.; Ramaprabhu, S., E-mail: ramp@iitm.ac.in

    2015-01-15

    Graphical abstract: Boron doped graphene (B-G), synthesized by simple hydrogen induced reduction technique using boric acid as boron precursor, have more uneven surface as a result of smaller bonding distance of boron compared to carbon, showed high capacity and high rate capability compared to pristine graphene as an anode material for Li ion battery application. - Abstract: The present work demonstrates a facile route for the large-scale, catalyst free, and green synthesis approach of boron doped graphene (B-G) and its use as high performance anode material for Li ion battery (LIB) application. Boron atoms were doped into graphene framework with an atomic percentage of 5.93% via hydrogen induced thermal reduction technique using graphite oxide and boric acid as precursors. Various characterization techniques were used to confirm the boron doping in graphene sheets. B-G as anode material shows a discharge capacity of 548 mAh g{sup −1} at 100 mA g{sup −1} after 30th cycles. At high current density value of 1 A g{sup −1}, B-G as anode material enhances the specific capacity by about 1.7 times compared to pristine graphene. The present study shows a simplistic way of boron doping in graphene leading to an enhanced Li ion adsorption due to the change in electronic states.

  2. Green synthesis of boron doped graphene and its application as high performance anode material in Li ion battery

    International Nuclear Information System (INIS)

    Sahoo, Madhumita; Sreena, K.P.; Vinayan, B.P.; Ramaprabhu, S.

    2015-01-01

    Graphical abstract: Boron doped graphene (B-G), synthesized by simple hydrogen induced reduction technique using boric acid as boron precursor, have more uneven surface as a result of smaller bonding distance of boron compared to carbon, showed high capacity and high rate capability compared to pristine graphene as an anode material for Li ion battery application. - Abstract: The present work demonstrates a facile route for the large-scale, catalyst free, and green synthesis approach of boron doped graphene (B-G) and its use as high performance anode material for Li ion battery (LIB) application. Boron atoms were doped into graphene framework with an atomic percentage of 5.93% via hydrogen induced thermal reduction technique using graphite oxide and boric acid as precursors. Various characterization techniques were used to confirm the boron doping in graphene sheets. B-G as anode material shows a discharge capacity of 548 mAh g −1 at 100 mA g −1 after 30th cycles. At high current density value of 1 A g −1 , B-G as anode material enhances the specific capacity by about 1.7 times compared to pristine graphene. The present study shows a simplistic way of boron doping in graphene leading to an enhanced Li ion adsorption due to the change in electronic states

  3. Bolivia. America = Las Americas [Series].

    Science.gov (United States)

    Toro, Leonor; Avery, Robert S.

    Written for teachers to use with migrant children in elementary grades and to highlight the many Americas, this bilingual English/Spanish social studies resource booklet provides historical and cultural information on Bolivia. A table of contents indicates the language--Spanish or English--in which the topics are written. The quarterly provides an…

  4. Structural characterization of electrodeposited boron

    Indian Academy of Sciences (India)

    Structural characterization of electrodeposited boron was carried out by using transmission electron microscopy and Raman spectroscopy. Electron diffraction and phase contrast imaging were carried out by using transmission electron microscopy. Phase identification was done based on the analysis of electron diffraction ...

  5. Boron isotopes in geothermal systems

    International Nuclear Information System (INIS)

    Aggarwal, J.

    1997-01-01

    Boron is a highly mobile element and during water-rock reactions, boron is leached out of rocks with no apparent fractionation. In geothermal systems where the water recharging the systems are meteoric in origin, the B isotope ratio of the geothermal fluid reflects the B isotope ratio of the rocks. Seawater has a distinctive B isotope ratio and where seawater recharges the geothermal system, the B isotope ratio of the geothermal system reflects the mixing of rock derived B and seawater derived B. Any deviations of the actual B isotope ratio of a mixture reflects subtle differences in the water-rock ratios in the cold downwelling limb of the hydrothermal system. This paper will present data from a variety of different geothermal systems, including New Zealand; Iceland; Yellowston, USA; Ibusuki, Japan to show the range in B isotope ratios in active geothermal systems. Some of these systems show well defined mixing trends between seawater and the host rocks, whilst others show the boron isotope ratios of the host rock only. In geothermal systems containing high amounts of CO 2 boron isotope ratios from a volatile B source can also be inferred. (auth)

  6. Structural characterization of electrodeposited boron

    Indian Academy of Sciences (India)

    high temperature reaction between elemental boron and car- bon to form B4C is .... cible was used as the container for the electrolyte and also acted as an anode. ... chosen as cathode due to its availability, low cost, ease of fabrication and ...

  7. Abstract Objects of Verbs

    DEFF Research Database (Denmark)

    Robering, Klaus

    2014-01-01

    Verbs do often take arguments of quite different types. In an orthodox type-theoretic framework this results in an extreme polysemy of many verbs. In this article, it is shown that this unwanted consequence can be avoided when a theory of "abstract objects" is adopted according to which these obj......Verbs do often take arguments of quite different types. In an orthodox type-theoretic framework this results in an extreme polysemy of many verbs. In this article, it is shown that this unwanted consequence can be avoided when a theory of "abstract objects" is adopted according to which...... these objects represent non-objectual entities in contexts from which they are excluded by type restrictions. Thus these objects are "abstract'' in a functional rather than in an ontological sense: they function as representatives of other entities but they are otherwise quite normal objects. Three examples...

  8. Boron-11 MRI and MRS of intact animals infused with a boron neutron capture agent

    International Nuclear Information System (INIS)

    Kabalka, G.W.; Davis, M.; Bendel, P.

    1988-01-01

    Boron neutron capture therapy (BNCT) depends on the delivery of boron-containing drugs to a targeted lesion. Currently, the verification and quantification of in vivo boron content is a difficult problem. Boron-11 spectroscopy was utilized to confirm the presence of a dimeric sulfhydryl dodecaborane BNCT agent contained in an intact animal. Spectroscopy experiments revealed that the decay time of transverse magnetization of the boron-11 spins was less than 1 ms which precluded the use of a 2DFT imaging protocol. A back-projection protocol was developed and utilized to generate the first boron-11 image of a BNCT agent in the liver of an intact Fisher 344 rat

  9. Building Safe Concurrency Abstractions

    DEFF Research Database (Denmark)

    Madsen, Ole Lehrmann

    2014-01-01

    Concurrent object-oriented programming in Beta is based on semaphores and coroutines and the ability to define high-level concurrency abstractions like monitors, and rendezvous-based communication, and their associated schedulers. The coroutine mechanism of SIMULA has been generalized into the no......Concurrent object-oriented programming in Beta is based on semaphores and coroutines and the ability to define high-level concurrency abstractions like monitors, and rendezvous-based communication, and their associated schedulers. The coroutine mechanism of SIMULA has been generalized...

  10. Abstract Objects of Verbs

    DEFF Research Database (Denmark)

    2014-01-01

    Verbs do often take arguments of quite different types. In an orthodox type-theoretic framework this results in an extreme polysemy of many verbs. In this article, it is shown that this unwanted consequence can be avoided when a theory of "abstract objects" is adopted according to which...... these objects represent non-objectual entities in contexts from which they are excluded by type restrictions. Thus these objects are "abstract'' in a functional rather than in an ontological sense: they function as representatives of other entities but they are otherwise quite normal objects. Three examples...

  11. Study on the preparation of boron-rich film by magnetron sputtering in oxygen atmosphere

    Energy Technology Data Exchange (ETDEWEB)

    Pan, Zhangmin; Yang, Yiming; Huang, Jian; Ren, Bing; Yu, Hongze; Xu, Run; Ji, Huanhuan; Wang, Lin; Wang, Linjun, E-mail: ljwang@shu.edu.cn

    2016-12-01

    Highlights: • Boron ({sup 10}B) oxide films were successfully grown using RF magnetron sputtering. • Effects of oxygen partial pressure on the property of the films were studied. • Substrates were covered with B-rich film and film surface was covered with B{sub 2}O{sub 3}. • The growth mechanism of films in oxygen atmosphere was analyzed using XPS. - Abstract: In this paper, the growth of boron ({sup 10}B) oxide films on (1 0 0) silicon substrate were achieved by radio frequency (r.f.) magnetron sputtering under the different oxygen partial pressure with a target of boron and boron oxide. The structure and properties of deposited films were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy spectrometer (FTIR), X-ray photoelectron spectroscopy (XPS), respectively. The results showed that the substrate was covered with boron-rich films tightly and the surface of films was covered with B{sub 2}O{sub 3}. And the growth mechanism of boron-rich film in oxygen atmosphere was also analyzed.

  12. Boron doped ZnO embedded into reduced graphene oxide for electrochemical supercapacitors

    Energy Technology Data Exchange (ETDEWEB)

    Alver, Ü., E-mail: ualver@ktu.edu.tr [Karadeniz Technical University, Dept. of Metallurgical and Materials Engineering, 61080 Trabzon (Turkey); Tanrıverdi, A. [Kahramanmaras Sutcu Imam University, Department of Physics, 46100 Kahramanmaraş (Turkey)

    2016-08-15

    Highlights: • Boron doped ZnO particles are fabricated and embedded into reduced graphene oxide (RGO) by hydrothermal method. • RGO/ZnO:B composites are used as electrodes for supercapacitors. • Presence of boron in RGO/ZnO composites caused increasing the stability and specific capacitance of electrodes. - Abstract: In this work, reduced graphene oxide/boron doped zinc oxide (RGO/ZnO:B) composites were fabricated by a hydrothermal process and their electrochemical properties were investigated as a function of dopant concentration. First, boron doped ZnO (ZnO:B) particles was fabricated with different boron concentrations (5, 10, 15 and 20 wt%) and then ZnO:B particles were embedded into RGO sheets. The physical properties of sensitized composites were characterized by XRD and SEM. Characterization indicated that the ZnO:B particles with plate-like structure in the composite were dispersed on graphene sheets. The electrochemical properties of the RGO/ZnO:B composite were investigated through cyclic voltammetry, galvanostatic charge/discharge measurements in a 6 M KOH electrolyte. Electrochemical measurements show that the specific capacitance values of RGO/ZnO:B electrodes increase with increasing boron concentration. RGO/ZnO:B composite electrodes (20 wt% B) display the specific capacitance as high as 230.50 F/g at 5 mV/s, which is almost five times higher than that of RGO/ZnO (52.71 F/g).

  13. Boron doped ZnO embedded into reduced graphene oxide for electrochemical supercapacitors

    International Nuclear Information System (INIS)

    Alver, Ü.; Tanrıverdi, A.

    2016-01-01

    Highlights: • Boron doped ZnO particles are fabricated and embedded into reduced graphene oxide (RGO) by hydrothermal method. • RGO/ZnO:B composites are used as electrodes for supercapacitors. • Presence of boron in RGO/ZnO composites caused increasing the stability and specific capacitance of electrodes. - Abstract: In this work, reduced graphene oxide/boron doped zinc oxide (RGO/ZnO:B) composites were fabricated by a hydrothermal process and their electrochemical properties were investigated as a function of dopant concentration. First, boron doped ZnO (ZnO:B) particles was fabricated with different boron concentrations (5, 10, 15 and 20 wt%) and then ZnO:B particles were embedded into RGO sheets. The physical properties of sensitized composites were characterized by XRD and SEM. Characterization indicated that the ZnO:B particles with plate-like structure in the composite were dispersed on graphene sheets. The electrochemical properties of the RGO/ZnO:B composite were investigated through cyclic voltammetry, galvanostatic charge/discharge measurements in a 6 M KOH electrolyte. Electrochemical measurements show that the specific capacitance values of RGO/ZnO:B electrodes increase with increasing boron concentration. RGO/ZnO:B composite electrodes (20 wt% B) display the specific capacitance as high as 230.50 F/g at 5 mV/s, which is almost five times higher than that of RGO/ZnO (52.71 F/g).

  14. Nuclear medicine. Abstracts

    International Nuclear Information System (INIS)

    Anon.

    2000-01-01

    This issue of the journal contains the abstracts of the 183 conference papers as well as 266 posters presented at the conference. Subject fields covered are: Neurology, psychology, oncology, pediatrics, radiopharmacy, endocrinology, EDP, measuring equipment and methods, radiological protection, cardiology, and therapy. (orig./CB) [de

  15. Seismic Consequence Abstraction

    International Nuclear Information System (INIS)

    Gross, M.

    2004-01-01

    The primary purpose of this model report is to develop abstractions for the response of engineered barrier system (EBS) components to seismic hazards at a geologic repository at Yucca Mountain, Nevada, and to define the methodology for using these abstractions in a seismic scenario class for the Total System Performance Assessment - License Application (TSPA-LA). A secondary purpose of this model report is to provide information for criticality studies related to seismic hazards. The seismic hazards addressed herein are vibratory ground motion, fault displacement, and rockfall due to ground motion. The EBS components are the drip shield, the waste package, and the fuel cladding. The requirements for development of the abstractions and the associated algorithms for the seismic scenario class are defined in ''Technical Work Plan For: Regulatory Integration Modeling of Drift Degradation, Waste Package and Drip Shield Vibratory Motion and Seismic Consequences'' (BSC 2004 [DIRS 171520]). The development of these abstractions will provide a more complete representation of flow into and transport from the EBS under disruptive events. The results from this development will also address portions of integrated subissue ENG2, Mechanical Disruption of Engineered Barriers, including the acceptance criteria for this subissue defined in Section 2.2.1.3.2.3 of the ''Yucca Mountain Review Plan, Final Report'' (NRC 2003 [DIRS 163274])

  16. Annual Conference Abstracts

    Science.gov (United States)

    Journal of Engineering Education, 1972

    1972-01-01

    Includes abstracts of papers presented at the 80th Annual Conference of the American Society for Engineering Education. The broad areas include aerospace, affiliate and associate member council, agricultural engineering, biomedical engineering, continuing engineering studies, chemical engineering, civil engineering, computers, cooperative…

  17. WWNPQFT-2013 - Abstracts

    International Nuclear Information System (INIS)

    Cessac, B.; Bianchi, E.; Bellon, M.; Fried, H.; Krajewski, T.; Schubert, C.; Barre, J.; Hofmann, R.; Muller, B.; Raffaelli, B.

    2014-01-01

    The object of this Workshop is to consolidate and publicize new efforts in non perturbative-like Field Theories, relying in Functional Methods, Renormalization Group, and Dyson-Schwinger Equations. A presentation deals with effective vertices and photon-photon scattering in SU(2) Yang-Mills thermodynamics. This document gathers the abstracts of the presentations

  18. Seismic Consequence Abstraction

    Energy Technology Data Exchange (ETDEWEB)

    M. Gross

    2004-10-25

    The primary purpose of this model report is to develop abstractions for the response of engineered barrier system (EBS) components to seismic hazards at a geologic repository at Yucca Mountain, Nevada, and to define the methodology for using these abstractions in a seismic scenario class for the Total System Performance Assessment - License Application (TSPA-LA). A secondary purpose of this model report is to provide information for criticality studies related to seismic hazards. The seismic hazards addressed herein are vibratory ground motion, fault displacement, and rockfall due to ground motion. The EBS components are the drip shield, the waste package, and the fuel cladding. The requirements for development of the abstractions and the associated algorithms for the seismic scenario class are defined in ''Technical Work Plan For: Regulatory Integration Modeling of Drift Degradation, Waste Package and Drip Shield Vibratory Motion and Seismic Consequences'' (BSC 2004 [DIRS 171520]). The development of these abstractions will provide a more complete representation of flow into and transport from the EBS under disruptive events. The results from this development will also address portions of integrated subissue ENG2, Mechanical Disruption of Engineered Barriers, including the acceptance criteria for this subissue defined in Section 2.2.1.3.2.3 of the ''Yucca Mountain Review Plan, Final Report'' (NRC 2003 [DIRS 163274]).

  19. Full Abstraction for HOPLA

    DEFF Research Database (Denmark)

    Nygaard, Mikkel; Winskel, Glynn

    2003-01-01

    A fully abstract denotational semantics for the higher-order process language HOPLA is presented. It characterises contextual and logical equivalence, the latter linking up with simulation. The semantics is a clean, domain-theoretic description of processes as downwards-closed sets of computation...

  20. Abstraction and art.

    Science.gov (United States)

    Gortais, Bernard

    2003-07-29

    In a given social context, artistic creation comprises a set of processes, which relate to the activity of the artist and the activity of the spectator. Through these processes we see and understand that the world is vaster than it is said to be. Artistic processes are mediated experiences that open up the world. A successful work of art expresses a reality beyond actual reality: it suggests an unknown world using the means and the signs of the known world. Artistic practices incorporate the means of creation developed by science and technology and change forms as they change. Artists and the public follow different processes of abstraction at different levels, in the definition of the means of creation, of representation and of perception of a work of art. This paper examines how the processes of abstraction are used within the framework of the visual arts and abstract painting, which appeared during a period of growing importance for the processes of abstraction in science and technology, at the beginning of the twentieth century. The development of digital platforms and new man-machine interfaces allow multimedia creations. This is performed under the constraint of phases of multidisciplinary conceptualization using generic representation languages, which tend to abolish traditional frontiers between the arts: visual arts, drama, dance and music.

  1. Composing Interfering Abstract Protocols

    Science.gov (United States)

    2016-04-01

    Tecnologia , Universidade Nova de Lisboa, Caparica, Portugal. This document is a companion technical report of the paper, “Composing Interfering Abstract...a Ciência e Tecnologia (Portuguese Foundation for Science and Technology) through the Carnegie Mellon Portugal Program under grant SFRH / BD / 33765

  2. Abstract algebra for physicists

    International Nuclear Information System (INIS)

    Zeman, J.

    1975-06-01

    Certain recent models of composite hadrons involve concepts and theorems from abstract algebra which are unfamiliar to most theoretical physicists. The algebraic apparatus needed for an understanding of these models is summarized here. Particular emphasis is given to algebraic structures which are not assumed to be associative. (2 figures) (auth)

  3. Reasoning abstractly about resources

    Science.gov (United States)

    Clement, B.; Barrett, A.

    2001-01-01

    r describes a way to schedule high level activities before distributing them across multiple rovers in order to coordinate the resultant use of shared resources regardless of how each rover decides how to perform its activities. We present an algorithm for summarizing the metric resource requirements of an abstract activity based n the resource usages of its potential refinements.

  4. Abstracts of submitted papers

    International Nuclear Information System (INIS)

    1987-01-01

    The conference proceedings contain 152 abstracts of presented papers relating to various aspects of personnel dosimetry, the dosimetry of the working and living environment, various types of dosemeters and spectrometers, the use of radionuclides in various industrial fields, the migration of radionuclides on Czechoslovak territory after the Chernobyl accident, theoretical studies of some parameters of ionizing radiation detectors, and their calibration. (M.D.)

  5. The Abstraction Engine

    DEFF Research Database (Denmark)

    Fortescue, Michael David

    The main thesis of this book is that abstraction, far from being confined to higher formsof cognition, language and logical reasoning, has actually been a major driving forcethroughout the evolution of creatures with brains. It is manifest in emotive as well as rationalthought. Wending its way th...

  6. Impredicative concurrent abstract predicates

    DEFF Research Database (Denmark)

    Svendsen, Kasper; Birkedal, Lars

    2014-01-01

    We present impredicative concurrent abstract predicates { iCAP { a program logic for modular reasoning about concurrent, higher- order, reentrant, imperative code. Building on earlier work, iCAP uses protocols to reason about shared mutable state. A key novel feature of iCAP is the ability to dene...

  7. Abstract Film and Beyond.

    Science.gov (United States)

    Le Grice, Malcolm

    A theoretical and historical account of the main preoccupations of makers of abstract films is presented in this book. The book's scope includes discussion of nonrepresentational forms as well as examination of experiments in the manipulation of time in films. The ten chapters discuss the following topics: art and cinematography, the first…

  8. SPR 2015. Abstracts

    International Nuclear Information System (INIS)

    2015-01-01

    The volume contains the abstracts of the SPR (society for pediatric radiology) 2015 meeting covering the following issues: fetal imaging, muscoskeletal imaging, cardiac imaging, chest imaging, oncologic imaging, tools for process improvement, child abuse, contrast enhanced ultrasound, image gently - update of radiation dose recording/reporting/monitoring - meaningful or useless meaning?, pediatric thoracic imaging, ALARA.

  9. Beyond the abstractions?

    DEFF Research Database (Denmark)

    Olesen, Henning Salling

    2006-01-01

      The anniversary of the International Journal of Lifelong Education takes place in the middle of a conceptual landslide from lifelong education to lifelong learning. Contemporary discourses of lifelong learning etc are however abstractions behind which new functions and agendas for adult education...

  10. Abstracts of SIG Sessions.

    Science.gov (United States)

    Proceedings of the ASIS Annual Meeting, 1994

    1994-01-01

    Includes abstracts of 18 special interest group (SIG) sessions. Highlights include natural language processing, information science and terminology science, classification, knowledge-intensive information systems, information value and ownership issues, economics and theories of information science, information retrieval interfaces, fuzzy thinking…

  11. Circularity and Lambda Abstraction

    DEFF Research Database (Denmark)

    Danvy, Olivier; Thiemann, Peter; Zerny, Ian

    2013-01-01

    unknowns from what is done to them, which we lambda-abstract with functions. The circular unknowns then become dead variables, which we eliminate. The result is a strict circu- lar program a la Pettorossi. This transformation is reversible: given a strict circular program a la Pettorossi, we introduce...

  12. SPR 2015. Abstracts

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2015-04-01

    The volume contains the abstracts of the SPR (society for pediatric radiology) 2015 meeting covering the following issues: fetal imaging, muscoskeletal imaging, cardiac imaging, chest imaging, oncologic imaging, tools for process improvement, child abuse, contrast enhanced ultrasound, image gently - update of radiation dose recording/reporting/monitoring - meaningful or useless meaning?, pediatric thoracic imaging, ALARA.

  13. Controlling groundwater over abstraction

    NARCIS (Netherlands)

    Naber, Al Majd; Molle, Francois

    2017-01-01

    The control of groundwater over abstraction is a vexing problem worldwide. Jordan is one of the countries facing severe water scarcity which has implemented a wide range of measures and policies over the past 20 years. While the gap between formal legal and policy frameworks and local practices on

  14. Monadic abstract interpreters

    DEFF Research Database (Denmark)

    Sergey, Ilya; Devriese, Dominique; Might, Matthew

    2013-01-01

    to instrument an analysis with high-level strategies for improving precision and performance, such as abstract garbage collection and widening. While the paper itself runs the development for continuationpassing style, our generic implementation replays it for direct-style lambda-calculus and Featherweight Java...

  15. EBS Radionuclide Transport Abstraction

    International Nuclear Information System (INIS)

    Schreiner, R.

    2001-01-01

    The purpose of this work is to develop the Engineered Barrier System (EBS) radionuclide transport abstraction model, as directed by a written development plan (CRWMS M and O 1999a). This abstraction is the conceptual model that will be used to determine the rate of release of radionuclides from the EBS to the unsaturated zone (UZ) in the total system performance assessment-license application (TSPA-LA). In particular, this model will be used to quantify the time-dependent radionuclide releases from a failed waste package (WP) and their subsequent transport through the EBS to the emplacement drift wall/UZ interface. The development of this conceptual model will allow Performance Assessment Operations (PAO) and its Engineered Barrier Performance Department to provide a more detailed and complete EBS flow and transport abstraction. The results from this conceptual model will allow PA0 to address portions of the key technical issues (KTIs) presented in three NRC Issue Resolution Status Reports (IRSRs): (1) the Evolution of the Near-Field Environment (ENFE), Revision 2 (NRC 1999a), (2) the Container Life and Source Term (CLST), Revision 2 (NRC 1999b), and (3) the Thermal Effects on Flow (TEF), Revision 1 (NRC 1998). The conceptual model for flow and transport in the EBS will be referred to as the ''EBS RT Abstraction'' in this analysis/modeling report (AMR). The scope of this abstraction and report is limited to flow and transport processes. More specifically, this AMR does not discuss elements of the TSPA-SR and TSPA-LA that relate to the EBS but are discussed in other AMRs. These elements include corrosion processes, radionuclide solubility limits, waste form dissolution rates and concentrations of colloidal particles that are generally represented as boundary conditions or input parameters for the EBS RT Abstraction. In effect, this AMR provides the algorithms for transporting radionuclides using the flow geometry and radionuclide concentrations determined by other

  16. Improving the electrochemical properties of nanosized LiFePO4-based electrode by boron doping

    International Nuclear Information System (INIS)

    Trócoli, Rafael; Franger, Sylvain; Cruz, Manuel; Morales, Julián; Santos-Peña, Jesús

    2014-01-01

    Highlights: • Thermal treatment of boron phosphate with LiFePO 4 provides electrode materials with high performance in lithium half-cells: 160 mAh·g -1 (90% of theoretical capacity) under C/5 rate • The products are composites containing boron-modified LiFePO 4 , FePO 4 and an amorphous phase with ionic diffusion properties • The boron treatment affects textural, conductive and lithium diffusivity of the electrode material leading to higher performance • A limited boron-doping of the phospholivine structure is observed - Abstract: Electrode materials with homogeneous distribution of boron were obtained by heating mixtures of nanosized carbon-coated lithium iron phosphate and BPO 4 in 3-9% weight at 700 °C. The materials can be described as nanocomposites containing i) LiFePO 4 , possibly doped with a low amount of boron, ii) FePO 4 and iii) an amorphous layer based on Li 4 P 2 O 7 -derived material that surrounds the phosphate particles. The thermal treatment with BPO 4 also triggered changes in the carbon coating graphitic order. Galvanostatic and voltammetric studies in lithium half-cells showed smaller polarisation, higher capacity and better cycle life for the boron-doped composites. For instance, one of the solids, called B 6 -LiFePO 4 , provided close to 150 and 140 mAhg -1 (87% and 81% of theoretical capacity, respectively) under C/2.5 and C regimes after several cycles. Improved specific surface area, carbon graphitization, conductivity and lithium ion diffusivity in the boron-doped phospholivine network account for this excellent rate performance. The properties of an amorphous layer surrounding the phosphate particles also account for such higher performance

  17. Ghana Science Abstracts

    International Nuclear Information System (INIS)

    Entsua-Mensah, C.

    2004-01-01

    This issue of the Ghana Science Abstracts combines in one publication all the country's bibliographic output in science and technology. The objective is to provide a quick reference source to facilitate the work of information professionals, research scientists, lecturers and policy makers. It is meant to give users an idea of the depth and scope and results of the studies and projects carried out. The scope and coverage comprise research outputs, conference proceedings and periodical articles published in Ghana. It does not capture those that were published outside Ghana. Abstracts reported have been grouped under the following subject areas: Agriculture, Biochemistry, Biodiversity conservation, biological sciences, biotechnology, chemistry, dentistry, engineering, environmental management, forestry, information management, mathematics, medicine, physics, nuclear science, pharmacy, renewable energy and science education

  18. Research Abstracts of 1979.

    Science.gov (United States)

    1979-12-01

    abscess formation and tissue necrosis, its relationship to periodontal pockets was investigated. Specimens were obtained from maxillary and mandibular...of Organisms and Periodontal Pockets." (Abstract 4853). 10. SIMONSON, Lo Go, LAMDERTS, B. L. and JACROLA, Do R. - "Effects of Dextranases and other...the tip of the periodontal probe rests within epithelium, at or slightly apical to the coronal extent of the junctional epithelium. The purpose of

  19. NPP life management (abstracts)

    International Nuclear Information System (INIS)

    Litvinskij, L.L.; Barbashev, S.V.

    2002-01-01

    Abstracts of the papers presented at the International conference of the Ukrainian Nuclear Society 'NPP Life Management'. The following problems are considered: modernization of the NPP; NPP life management; waste and spent nuclear fuel management; decommissioning issues; control systems (including radiation and ecological control systems); information and control systems; legal and regulatory framework. State nuclear regulatory control; PR in nuclear power; training of personnel; economics of nuclear power engineering

  20. Research Abstracts of 1982.

    Science.gov (United States)

    1982-12-01

    Third Molars in Naval Personnel,- (Abstract #1430) 7. A. SEROWSKI* and F. AKER --"The Effect of Marine and Fresh-Water Atmospheric Environments on...record to determine changes in surface coverage or other outcomes -- extraction, endodontic therapy , crown placement -- which occurred over time. The...MR0412002-0443. 0 e5 History of Retention and Extraction of Third Molars in Naval Personnel. D. C. SCHROEDER*, J. C. CECIL and M. E. COHEN. Naval

  1. DEGRO 2017. Abstracts

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2017-06-15

    The volume includes abstracts of the Annual DEGRO Meeting 2017 covering lectures and poster sessions with the following issues: lymphoma, biology, physics, radioimmunotherapy, sarcomas and rare tumors, prostate carcinoma, lung tumors, benign lesions and new media, mamma carcinoma, gastrointestinal tumors, quality of life, care science and quality assurance, high-technology methods and palliative situation, head-and-neck tumors, brain tumors, central nervous system metastases, guidelines, radiation sensitivity, radiotherapy, radioimmunotherapy.

  2. Medical physics 2013. Abstracts

    International Nuclear Information System (INIS)

    Treuer, Harald

    2013-01-01

    The proceedings of the medical physics conference 2013 include abstract of lectures and poster sessions concerning the following issues: Tele-therapy - application systems, nuclear medicine and molecular imaging, neuromodulation, hearing and technical support, basic dosimetry, NMR imaging -CEST (chemical exchange saturation transfer), medical robotics, magnetic particle imaging, audiology, radiation protection, phase contrast - innovative concepts, particle therapy, brachytherapy, computerized tomography, quantity assurance, hybrid imaging techniques, diffusion and lung NMR imaging, image processing - visualization, cardiac and abdominal NMR imaging.

  3. SPR 2014. Abstracts

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2014-05-15

    The proceedings of the SPR 2014 meeting include abstracts on the following topics: Body imaging techniques: practical advice for clinic work; thoracic imaging: focus on the lungs; gastrointestinal imaging: focus on the pancreas and bowel; genitourinary imaging: focus on gonadal radiology; muscoskeletal imaging; focus on oncology; child abuse and nor child abuse: focus on radiography; impact of NMR and CT imaging on management of CHD; education and communication: art and practice in pediatric radiology.

  4. SPR 2014. Abstracts

    International Nuclear Information System (INIS)

    2014-01-01

    The proceedings of the SPR 2014 meeting include abstracts on the following topics: Body imaging techniques: practical advice for clinic work; thoracic imaging: focus on the lungs; gastrointestinal imaging: focus on the pancreas and bowel; genitourinary imaging: focus on gonadal radiology; muscoskeletal imaging; focus on oncology; child abuse and nor child abuse: focus on radiography; impact of NMR and CT imaging on management of CHD; education and communication: art and practice in pediatric radiology.

  5. WWNPQFT-2011 - Abstracts

    International Nuclear Information System (INIS)

    Bianchi, E.; Bender, C.; Culetu, H.; Fried, H.; Grossmann, A.; Hofmann, R.; Le Bellac, M.; Martinetti, P.; Muller, B.; Patras, F.; Raffaeli, B.; Vitting Andersen, J.

    2013-01-01

    The object of this workshop is to consolidate and publicize new efforts in non-perturbative field theories. This year the presentations deal with quantum gravity, non-commutative geometry, fat-tailed wave-functions, strongly coupled field theories, space-times two time-like dimensions, and multiplicative renormalization. A presentation is dedicated to the construction of a nucleon-nucleon potential from an analytical, non-perturbative gauge invariant QCD. This document gathers the abstracts of the presentations

  6. Helium diffusion in irradiated boron carbide

    International Nuclear Information System (INIS)

    Hollenberg, G.W.

    1981-03-01

    Boron carbide has been internationally adopted as the neutron absorber material in the control and safety rods of large fast breeder reactors. Its relatively large neutron capture cross section at high neutron energies provides sufficient reactivity worth with a minimum of core space. In addition, the commercial availability of boron carbide makes it attractive from a fabrication standpoint. Instrumented irradiation experiments in EBR-II have provided continuous helium release data on boron carbide at a variety of operating temperatures. Although some microstructural and compositional variations were examined in these experiments most of the boron carbide was prototypic of that used in the Fast Flux Test Facility. The density of the boron carbide pellets was approximately 92% of theoretical. The boron carbide pellets were approximately 1.0 cm in diameter and possessed average grain sizes that varied from 8 to 30 μm. Pellet centerline temperatures were continually measured during the irradiation experiments

  7. EBS Radionuclide Transport Abstraction

    International Nuclear Information System (INIS)

    J. Prouty

    2006-01-01

    The purpose of this report is to develop and analyze the engineered barrier system (EBS) radionuclide transport abstraction model, consistent with Level I and Level II model validation, as identified in Technical Work Plan for: Near-Field Environment and Transport: Engineered Barrier System: Radionuclide Transport Abstraction Model Report Integration (BSC 2005 [DIRS 173617]). The EBS radionuclide transport abstraction (or EBS RT Abstraction) is the conceptual model used in the total system performance assessment (TSPA) to determine the rate of radionuclide releases from the EBS to the unsaturated zone (UZ). The EBS RT Abstraction conceptual model consists of two main components: a flow model and a transport model. Both models are developed mathematically from first principles in order to show explicitly what assumptions, simplifications, and approximations are incorporated into the models used in the TSPA. The flow model defines the pathways for water flow in the EBS and specifies how the flow rate is computed in each pathway. Input to this model includes the seepage flux into a drift. The seepage flux is potentially split by the drip shield, with some (or all) of the flux being diverted by the drip shield and some passing through breaches in the drip shield that might result from corrosion or seismic damage. The flux through drip shield breaches is potentially split by the waste package, with some (or all) of the flux being diverted by the waste package and some passing through waste package breaches that might result from corrosion or seismic damage. Neither the drip shield nor the waste package survives an igneous intrusion, so the flux splitting submodel is not used in the igneous scenario class. The flow model is validated in an independent model validation technical review. The drip shield and waste package flux splitting algorithms are developed and validated using experimental data. The transport model considers advective transport and diffusive transport

  8. EBS Radionuclide Transport Abstraction

    Energy Technology Data Exchange (ETDEWEB)

    J. Prouty

    2006-07-14

    The purpose of this report is to develop and analyze the engineered barrier system (EBS) radionuclide transport abstraction model, consistent with Level I and Level II model validation, as identified in Technical Work Plan for: Near-Field Environment and Transport: Engineered Barrier System: Radionuclide Transport Abstraction Model Report Integration (BSC 2005 [DIRS 173617]). The EBS radionuclide transport abstraction (or EBS RT Abstraction) is the conceptual model used in the total system performance assessment (TSPA) to determine the rate of radionuclide releases from the EBS to the unsaturated zone (UZ). The EBS RT Abstraction conceptual model consists of two main components: a flow model and a transport model. Both models are developed mathematically from first principles in order to show explicitly what assumptions, simplifications, and approximations are incorporated into the models used in the TSPA. The flow model defines the pathways for water flow in the EBS and specifies how the flow rate is computed in each pathway. Input to this model includes the seepage flux into a drift. The seepage flux is potentially split by the drip shield, with some (or all) of the flux being diverted by the drip shield and some passing through breaches in the drip shield that might result from corrosion or seismic damage. The flux through drip shield breaches is potentially split by the waste package, with some (or all) of the flux being diverted by the waste package and some passing through waste package breaches that might result from corrosion or seismic damage. Neither the drip shield nor the waste package survives an igneous intrusion, so the flux splitting submodel is not used in the igneous scenario class. The flow model is validated in an independent model validation technical review. The drip shield and waste package flux splitting algorithms are developed and validated using experimental data. The transport model considers advective transport and diffusive transport

  9. Primary system boron dilution analysis

    International Nuclear Information System (INIS)

    Crump, R.J.; Naretto, C.J.; Borgen, R.A.; Rockhold, H.C.

    1978-01-01

    The results are presented for an analysis conducted to determine the potential paths through which nonborated water or water with insufficient boron concentration might enter the LOFT primary coolant piping system or reactor vessel to cause dilution of the borated primary coolant water. No attempt was made in the course of this analysis to identify possible design modifications nor to suggest changes in administrative procedures or controls

  10. Boron removal from geothermal waters by electrocoagulation

    Energy Technology Data Exchange (ETDEWEB)

    Yilmaz, A. Erdem [Atatuerk University, Faculty of Engineering, Department of Environmental Engineering., 25240 Erzurum (Turkey)], E-mail: aerdemy@atauni.edu.tr; Boncukcuoglu, Recep [Atatuerk University, Faculty of Engineering, Department of Environmental Engineering., 25240 Erzurum (Turkey); Kocakerim, M. Muhtar [Atatuerk University, Faculty of Engineering, Department of Chemical Engineering, 25240 Erzurum (Turkey); Yilmaz, M. Tolga; Paluluoglu, Cihan [Atatuerk University, Faculty of Engineering, Department of Environmental Engineering., 25240 Erzurum (Turkey)

    2008-05-01

    Most of the geothermal waters in Turkey contain extremely high concentration of boron when they are used for irrigation. The use of geothermal waters for irrigation can results in excess amount deposition of boron in soil. On the other hand, a minimal boron concentration is required for irrigational waters. In this study, electrocoagulation (EC) was selected as a treatment process for the removal of boron from thermal waters obtained from Ilica-Erzurum in Turkey. Current density (CD), pH of solution and temperature of solution were selected as operational parameters. The results showed that boron removal efficiency increased from pH 4.0 to 8.0 and decreased at pH 10.0. Although boron removal efficiency was highest at pH 8.0, energy consumption was very high at this pH value compared to other pH intervals. Boron removal efficiency reached to 95% with increasing current density from 1.5 to 6.0 mA/cm{sup 2}, but energy consumption was also increased in this interval. At higher temperatures of solution, such as 313 and 333 K, boron removal efficiency increased. At optimum conditions, boron removal efficiency in geothermal water reached up to 95%.

  11. Boron removal from geothermal waters by electrocoagulation

    International Nuclear Information System (INIS)

    Yilmaz, A. Erdem; Boncukcuoglu, Recep; Kocakerim, M. Muhtar; Yilmaz, M. Tolga; Paluluoglu, Cihan

    2008-01-01

    Most of the geothermal waters in Turkey contain extremely high concentration of boron when they are used for irrigation. The use of geothermal waters for irrigation can results in excess amount deposition of boron in soil. On the other hand, a minimal boron concentration is required for irrigational waters. In this study, electrocoagulation (EC) was selected as a treatment process for the removal of boron from thermal waters obtained from Ilica-Erzurum in Turkey. Current density (CD), pH of solution and temperature of solution were selected as operational parameters. The results showed that boron removal efficiency increased from pH 4.0 to 8.0 and decreased at pH 10.0. Although boron removal efficiency was highest at pH 8.0, energy consumption was very high at this pH value compared to other pH intervals. Boron removal efficiency reached to 95% with increasing current density from 1.5 to 6.0 mA/cm 2 , but energy consumption was also increased in this interval. At higher temperatures of solution, such as 313 and 333 K, boron removal efficiency increased. At optimum conditions, boron removal efficiency in geothermal water reached up to 95%

  12. Removal of boron (B) from waste liquors.

    Science.gov (United States)

    Jiang, J Q; Xu, Y; Simon, J; Quill, K; Shettle, K

    2006-01-01

    This paper explores the use of electrocoagulation to remove boron from waste effluent in comparison with alum coagulation. In treating model test wastes, greater boron removals were achieved with electrocoagulation at low doses than conventional alum coagulation when reaction was undertaken for the same conditions (pH 8.5, and initial boron concentration was 500 mg/L). Al electrocoagulation can achieve good boron removal performance (68.3%) at a dose of 2.1 (as molar ratio of Al:B, and for current density of 62.1 A/m2), while alum coagulation can only achieve the maximum boron removal of 56% at a dose of 2.4. Also, Al electrocoagulation can remove 15-20% more boron than alum coagulation for the same dose compared in the treatment of both model test wastes and industry effluent. The estimation of running costs shows that to achieve 75% boron removal from industry waste effluent, i.e. removing 150 g of boron from 1 m3 of effluent, electrocoagulation was 6.2 times cheaper than alum coagulation. The economic advantage of electrocoagulation in the treatment of boron-containing waste effluent is thus significant.

  13. Non-equilibrium mass transfer absorption model for the design of boron isotopes chemical exchange column

    International Nuclear Information System (INIS)

    Bai, Peng; Fan, Kaigong; Guo, Xianghai; Zhang, Haocui

    2016-01-01

    Highlights: • We propose a non-equilibrium mass transfer absorption model instead of a distillation equilibrium model to calculate boron isotopes separation. • We apply the model to calculate the needed column height to meet prescribed separation requirements. - Abstract: To interpret the phenomenon of chemical exchange in boron isotopes separation accurately, the process is specified as an absorption–reaction–desorption hybrid process instead of a distillation equilibrium model, the non-equilibrium mass transfer absorption model is put forward and a mass transfer enhancement factor E is introduced to find the packing height needed to meet the specified separation requirements with MATLAB.

  14. Program and abstracts

    International Nuclear Information System (INIS)

    1978-01-01

    This volume contains the program and abstracts of the conference. The following topics are included: metal vapor molecular lasers, magnetohydrodynamics, rare gas halide and nuclear pumped lasers, transfer mechanisms in arcs, kinetic processes in rare gas halide lasers, arcs and flows, XeF kinetics and lasers, fundamental processes in excimer lasers, electrode effects and vacuum arcs, electron and ion transport, ion interactions and mobilities, glow discharges, diagnostics and afterglows, dissociative recombination, electron ionization and excitation, rare gas excimers and group VI lasers, breakdown, novel laser pumping techniques, electrode-related discharge phenomena, photon interactions, attachment, plasma chemistry and infrared lasers, electron scattering, and reactions of excited species

  15. Elements of abstract algebra

    CERN Document Server

    Clark, Allan

    1984-01-01

    This concise, readable, college-level text treats basic abstract algebra in remarkable depth and detail. An antidote to the usual surveys of structure, the book presents group theory, Galois theory, and classical ideal theory in a framework emphasizing proof of important theorems.Chapter I (Set Theory) covers the basics of sets. Chapter II (Group Theory) is a rigorous introduction to groups. It contains all the results needed for Galois theory as well as the Sylow theorems, the Jordan-Holder theorem, and a complete treatment of the simplicity of alternating groups. Chapter III (Field Theory)

  16. SPR 2017. Abstracts

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2017-05-15

    The conference proceedings SPR 2017 include abstracts on the following issues: gastrointestinal radiography - inflammatory bowel diseases, cardiovascular CTA, general muscoskeletal radiology, muscoskeletal congenital development diseases, general pediatric radiology - chest, muscoskeletal imaging - marrow and infectious disorders, state-of-the-art body MR imaging, practical pediatric sonography, quality and professionalism, CT imaging in congenital heart diseases, radiographic courses, body MT techniques, contrast enhanced ultrasound, machine learning, forensic imaging, the radiation dos conundrum - reconciling imaging, imagining and managing, the practice of radiology, interventional radiology, neuroradiology, PET/MR.

  17. Ghana energy abstracts

    International Nuclear Information System (INIS)

    Entsua-Mensah, Clement

    1994-01-01

    Ghana Energy Abstracts 1994 is the first issue of an annual publication of the Energy information Centre. The aim is to combine in one publication the country' s bibliographic output on energy so as to provide a valuable source of reference for policy makers, planners,and researchers. It covers the broad spectrum of energy including; energy conservation, energy resource management, petroleum and renewable energy resources.The documents listed comprise research reports, baseline studies,conference proceedings, periodical articles dissertations and theses. Keywords and author indexes have been provided to facilitate easy reference. (C.E.M)

  18. Parameterized Dataflow (Extended Abstract

    Directory of Open Access Journals (Sweden)

    Dominic Duggan

    2016-10-01

    Full Text Available Dataflow networks have application in various forms of stream processing, for example for parallel processing of multimedia data. The description of dataflow graphs, including their firing behavior, is typically non-compositional and not amenable to separate compilation. This article considers a dataflow language with a type and effect system that captures the firing behavior of actors. This system allows definitions to abstract over actor firing rates, supporting the definition and safe composition of actor definitions where firing rates are not instantiated until a dataflow graph is launched.

  19. ESPR 2015. Abstracts

    International Nuclear Information System (INIS)

    2015-01-01

    The volume includes the abstracts of the ESPR 2015 covering the following topics: PCG (post graduate courses): Radiography; fluoroscopy and general issue; nuclear medicine, interventional radiology and hybrid imaging, pediatric CT, pediatric ultrasound; MRI in childhood. Scientific sessions and task force sessions: International aspects; neuroradiology, neonatal imaging, engineering techniques to simulate injury in child abuse, CT - dose and quality, challenges in the chest, cardiovascular and chest, muscoskeletal, oncology, pediatric uroradiology and abdominal imaging, fetal and postmortem imaging, education and global challenges, neuroradiology - head and neck, gastrointestinal and genitourinary.

  20. ABSTRACTION OF DRIFT SEEPAGE

    International Nuclear Information System (INIS)

    Wilson, Michael L.

    2001-01-01

    Drift seepage refers to flow of liquid water into repository emplacement drifts, where it can potentially contribute to degradation of the engineered systems and release and transport of radionuclides within the drifts. Because of these important effects, seepage into emplacement drifts is listed as a ''principal factor for the postclosure safety case'' in the screening criteria for grading of data in Attachment 1 of AP-3.15Q, Rev. 2, ''Managing Technical Product Inputs''. Abstraction refers to distillation of the essential components of a process model into a form suitable for use in total-system performance assessment (TSPA). Thus, the purpose of this analysis/model is to put the information generated by the seepage process modeling in a form appropriate for use in the TSPA for the Site Recommendation. This report also supports the Unsaturated-Zone Flow and Transport Process Model Report. The scope of the work is discussed below. This analysis/model is governed by the ''Technical Work Plan for Unsaturated Zone Flow and Transport Process Model Report'' (CRWMS MandO 2000a). Details of this activity are in Addendum A of the technical work plan. The original Work Direction and Planning Document is included as Attachment 7 of Addendum A. Note that the Work Direction and Planning Document contains tasks identified for both Performance Assessment Operations (PAO) and Natural Environment Program Operations (NEPO). Only the PAO tasks are documented here. The planning for the NEPO activities is now in Addendum D of the same technical work plan and the work is documented in a separate report (CRWMS MandO 2000b). The Project has been reorganized since the document was written. The responsible organizations in the new structure are the Performance Assessment Department and the Unsaturated Zone Department, respectively. The work plan for the seepage abstraction calls for determining an appropriate abstraction methodology, determining uncertainties in seepage, and providing

  1. IPR 2016. Abstracts

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2016-05-15

    The volume on the meeting of pediatric radiology includes abstract on the following issues: chest, cardiovascular system, neuroradiology, CT radiation DRs (diagnostic reference levels) and dose reporting guidelines, genitourinary imaging, gastrointestinal radiology, oncology an nuclear medicine, whole body imaging, fetal/neonates imaging, child abuse, oncology and hybrid imaging, value added imaging, muscoskeletal imaging, dose and radiation safety, imaging children - immobilization and distraction techniques, information - education - QI and healthcare policy, ALARA, the knowledge skills and competences for a technologist/radiographer in pediatric radiology, full exploitation of new technological features in pediatric CT, image quality issues in pediatrics, abdominal imaging, interventional radiology, MR contrast agents, tumor - mass imaging, cardiothoracic imaging, ultrasonography.

  2. ESPR 2015. Abstracts

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2015-05-10

    The volume includes the abstracts of the ESPR 2015 covering the following topics: PCG (post graduate courses): Radiography; fluoroscopy and general issue; nuclear medicine, interventional radiology and hybrid imaging, pediatric CT, pediatric ultrasound; MRI in childhood. Scientific sessions and task force sessions: International aspects; neuroradiology, neonatal imaging, engineering techniques to simulate injury in child abuse, CT - dose and quality, challenges in the chest, cardiovascular and chest, muscoskeletal, oncology, pediatric uroradiology and abdominal imaging, fetal and postmortem imaging, education and global challenges, neuroradiology - head and neck, gastrointestinal and genitourinary.

  3. IPR 2016. Abstracts

    International Nuclear Information System (INIS)

    2016-01-01

    The volume on the meeting of pediatric radiology includes abstract on the following issues: chest, cardiovascular system, neuroradiology, CT radiation DRs (diagnostic reference levels) and dose reporting guidelines, genitourinary imaging, gastrointestinal radiology, oncology an nuclear medicine, whole body imaging, fetal/neonates imaging, child abuse, oncology and hybrid imaging, value added imaging, muscoskeletal imaging, dose and radiation safety, imaging children - immobilization and distraction techniques, information - education - QI and healthcare policy, ALARA, the knowledge skills and competences for a technologist/radiographer in pediatric radiology, full exploitation of new technological features in pediatric CT, image quality issues in pediatrics, abdominal imaging, interventional radiology, MR contrast agents, tumor - mass imaging, cardiothoracic imaging, ultrasonography.

  4. EBS Radionuclide Transport Abstraction

    Energy Technology Data Exchange (ETDEWEB)

    J.D. Schreiber

    2005-08-25

    The purpose of this report is to develop and analyze the engineered barrier system (EBS) radionuclide transport abstraction model, consistent with Level I and Level II model validation, as identified in ''Technical Work Plan for: Near-Field Environment and Transport: Engineered Barrier System: Radionuclide Transport Abstraction Model Report Integration'' (BSC 2005 [DIRS 173617]). The EBS radionuclide transport abstraction (or EBS RT Abstraction) is the conceptual model used in the total system performance assessment for the license application (TSPA-LA) to determine the rate of radionuclide releases from the EBS to the unsaturated zone (UZ). The EBS RT Abstraction conceptual model consists of two main components: a flow model and a transport model. Both models are developed mathematically from first principles in order to show explicitly what assumptions, simplifications, and approximations are incorporated into the models used in the TSPA-LA. The flow model defines the pathways for water flow in the EBS and specifies how the flow rate is computed in each pathway. Input to this model includes the seepage flux into a drift. The seepage flux is potentially split by the drip shield, with some (or all) of the flux being diverted by the drip shield and some passing through breaches in the drip shield that might result from corrosion or seismic damage. The flux through drip shield breaches is potentially split by the waste package, with some (or all) of the flux being diverted by the waste package and some passing through waste package breaches that might result from corrosion or seismic damage. Neither the drip shield nor the waste package survives an igneous intrusion, so the flux splitting submodel is not used in the igneous scenario class. The flow model is validated in an independent model validation technical review. The drip shield and waste package flux splitting algorithms are developed and validated using experimental data. The transport

  5. EBS Radionuclide Transport Abstraction

    International Nuclear Information System (INIS)

    J.D. Schreiber

    2005-01-01

    The purpose of this report is to develop and analyze the engineered barrier system (EBS) radionuclide transport abstraction model, consistent with Level I and Level II model validation, as identified in ''Technical Work Plan for: Near-Field Environment and Transport: Engineered Barrier System: Radionuclide Transport Abstraction Model Report Integration'' (BSC 2005 [DIRS 173617]). The EBS radionuclide transport abstraction (or EBS RT Abstraction) is the conceptual model used in the total system performance assessment for the license application (TSPA-LA) to determine the rate of radionuclide releases from the EBS to the unsaturated zone (UZ). The EBS RT Abstraction conceptual model consists of two main components: a flow model and a transport model. Both models are developed mathematically from first principles in order to show explicitly what assumptions, simplifications, and approximations are incorporated into the models used in the TSPA-LA. The flow model defines the pathways for water flow in the EBS and specifies how the flow rate is computed in each pathway. Input to this model includes the seepage flux into a drift. The seepage flux is potentially split by the drip shield, with some (or all) of the flux being diverted by the drip shield and some passing through breaches in the drip shield that might result from corrosion or seismic damage. The flux through drip shield breaches is potentially split by the waste package, with some (or all) of the flux being diverted by the waste package and some passing through waste package breaches that might result from corrosion or seismic damage. Neither the drip shield nor the waste package survives an igneous intrusion, so the flux splitting submodel is not used in the igneous scenario class. The flow model is validated in an independent model validation technical review. The drip shield and waste package flux splitting algorithms are developed and validated using experimental data. The transport model considers

  6. A technique to prepare boronated B72.3 monoclonal antibody for boron neutron capture therapy

    International Nuclear Information System (INIS)

    Ranadive, G.N.; Rosenzweig, H.S.; Epperly, M.W.

    1993-01-01

    B72.3 monoclonal antibody has been successfully boronated using mercaptoundecahydro-closo-dodecaborate (boron cage compound). The reagent was incorporated by first reacting the lysine residues of the antibody with m-maleimidobenzoyl succinimide ester (MBS), followed by Michael addition to the maleimido group by the mercapto boron cage compound to form a physiologically stable thioether linkage. Boron content of the antibody was determined by atomic absorption spectroscopy. For biodistribution studies, boronated antibody was radioiodinated with iodogen. 125 I-labeled and boronated B72.3 monoclonal antibody demonstrated clear tumor localization when administered via tail vein injections to athymic nude mice bearing LS174-T tumor xenografts. Boronated antibody was calculated to deliver 10 6 boron atoms per tumor cell. Although this falls short of the specific boron content originally proposed as necessary for boron neutron capture therapy (BNCT), recent calculations suggest that far fewer atoms of 10 B per tumor cell would be necessary to effect successful BNCT when the boron is targeted to the tumor cell membrane. (author)

  7. Evaluation of mechanical properties of aluminium alloy–alumina–boron carbide metal matrix composites

    International Nuclear Information System (INIS)

    Vijaya Ramnath, B.; Elanchezhian, C.; Jaivignesh, M.; Rajesh, S.; Parswajinan, C.; Siddique Ahmed Ghias, A.

    2014-01-01

    Highlights: • Fabrication of MMC with aluminium alloy–alumina–boron carbide is done. • Different proportions of reinforcements are added. • The effects of varying proportions are studied. • Investigation on mechanical properties above composites is performed. • Failure morphology analysis is done using SEM. - Abstract: This paper deals with the fabrication and mechanical investigation of aluminium alloy, alumina (Al 2 O 3 ) and boron carbide metal matrix composites. Aluminium is the matrix metal having properties like light weight, high strength and ease of machinability. Alumina which has better wear resistance, high strength, hardness and boron carbide which has excellent hardness and fracture toughness are added as reinforcements. Here, the fabrication is done by stir casting which involves mixing the required quantities of additives into stirred molten aluminium. After solidification, the samples are prepared and tested to find the various mechanical properties like tensile, flexural, impact and hardness. The internal structure of the composite is observed using Scanning Electron Microscope (SEM)

  8. Boron carbide synthesis by carbothermic reduction of boron oxide

    International Nuclear Information System (INIS)

    Castro, A.R.M. de; Paschoal, J.O.A.

    1988-01-01

    Boron carbide (B 4 C) is a ceramic material of technological applications due to its extreme hardness and high chemical as well as thermal stability. Some parameters of the process for obtaining B 4 C by carbothermic reduction of B 2 O 3 have been determined. The starting powders and the final products have been analysed by chemical, spectrographic and X-ray diffraction methods. The results show that the B 4 C obtained by the carbothermic reduction process is suitable for applications with a definite determination of the free carbon content. (author) [pt

  9. Problems in abstract algebra

    CERN Document Server

    Wadsworth, A R

    2017-01-01

    This is a book of problems in abstract algebra for strong undergraduates or beginning graduate students. It can be used as a supplement to a course or for self-study. The book provides more variety and more challenging problems than are found in most algebra textbooks. It is intended for students wanting to enrich their learning of mathematics by tackling problems that take some thought and effort to solve. The book contains problems on groups (including the Sylow Theorems, solvable groups, presentation of groups by generators and relations, and structure and duality for finite abelian groups); rings (including basic ideal theory and factorization in integral domains and Gauss's Theorem); linear algebra (emphasizing linear transformations, including canonical forms); and fields (including Galois theory). Hints to many problems are also included.

  10. ICENES 2007 Abstracts

    Energy Technology Data Exchange (ETDEWEB)

    Sahin, S [Gazi University, Technical Education Faculty, Ankara (Turkey)

    2007-07-01

    In this book Conference Program and Abstracts were included 13th International Conference on Emerging Nuclear Energy Systems which held between 03-08 June 2007 in Istanbul, Turkey. The main objective of International Conference series on Emerging Nuclear Energy Systems (ICENES) is to provide an international scientific and technical forum for scientists, engineers, industry leaders, policy makers, decision makers and young professionals who will shape future energy supply and technology , for a broad review and discussion of various advanced, innovative and non-conventional nuclear energy production systems. The main topics of 159 accepted papers from 35 countries are fusion science and technology, fission reactors, accelerator driven systems, transmutation, laser in nuclear technology, radiation shielding, nuclear reactions, hydrogen energy, solar energy, low energy physics and societal issues.

  11. ICENES 2007 Abstracts

    International Nuclear Information System (INIS)

    Sahin, S.

    2007-01-01

    In this book Conference Program and Abstracts were included 13th International Conference on Emerging Nuclear Energy Systems which held between 03-08 June 2007 in Istanbul, Turkey. The main objective of International Conference series on Emerging Nuclear Energy Systems (ICENES) is to provide an international scientific and technical forum for scientists, engineers, industry leaders, policy makers, decision makers and young professionals who will shape future energy supply and technology , for a broad review and discussion of various advanced, innovative and non-conventional nuclear energy production systems. The main topics of 159 accepted papers from 35 countries are fusion science and technology, fission reactors, accelerator driven systems, transmutation, laser in nuclear technology, radiation shielding, nuclear reactions, hydrogen energy, solar energy, low energy physics and societal issues

  12. Computational Abstraction Steps

    DEFF Research Database (Denmark)

    Thomsen, Lone Leth; Thomsen, Bent; Nørmark, Kurt

    2010-01-01

    and class instantiations. Our teaching experience shows that many novice programmers find it difficult to write programs with abstractions that materialise to concrete objects later in the development process. The contribution of this paper is the idea of initiating a programming process by creating...... or capturing concrete values, objects, or actions. As the next step, some of these are lifted to a higher level by computational means. In the object-oriented paradigm the target of such steps is classes. We hypothesise that the proposed approach primarily will be beneficial to novice programmers or during...... the exploratory phase of a program development process. In some specific niches it is also expected that our approach will benefit professional programmers....

  13. IEEE conference record -- Abstracts

    International Nuclear Information System (INIS)

    Anon.

    1994-01-01

    This conference covers the following areas: computational plasma physics; vacuum electronic; basic phenomena in fully ionized plasmas; plasma, electron, and ion sources; environmental/energy issues in plasma science; space plasmas; plasma processing; ball lightning/spherical plasma configurations; plasma processing; fast wave devices; magnetic fusion; basic phenomena in partially ionized plasma; dense plasma focus; plasma diagnostics; basic phenomena in weakly ionized gases; fast opening switches; MHD; fast z-pinches and x-ray lasers; intense ion and electron beams; laser-produced plasmas; microwave plasma interactions; EM and ETH launchers; solid state plasmas and switches; intense beam microwaves; and plasmas for lighting. Separate abstracts were prepared for 416 papers in this conference

  14. Front and back side SIMS analysis of boron-doped delta-layer in diamond

    Energy Technology Data Exchange (ETDEWEB)

    Pinault-Thaury, M.-A., E-mail: marie-amandine.pinault-thaury@uvsq.fr [Groupe d’Etude de la Matière Condensée, CNRS, University of Paris Saclay, University of Versailles St Quentin, 45 Avenue des Etats-Unis, 78035 Versailles Cedex (France); Jomard, F. [Groupe d’Etude de la Matière Condensée, CNRS, University of Paris Saclay, University of Versailles St Quentin, 45 Avenue des Etats-Unis, 78035 Versailles Cedex (France); Mer-Calfati, C.; Tranchant, N.; Pomorski, M.; Bergonzo, P.; Arnault, J.-C. [CEA, LIST, Diamond Sensors Laboratory, 91191 Gif-sur-Yvette (France)

    2017-07-15

    Highlights: • Front and back side SIMS analysis of delta-layer boron-doped is a first for diamond. • Combination of front and back side depth profiling improves delta-layer analyses. • Sharp interfaces are evidenced on both sides of the delta-layer boron-doped diamond. • The growth of delta-layer boron doped diamond is now well controlled. - Abstract: Nowadays the availability of very thin diamond layers in the range of nanometers as well as the possibility to characterize such delta-layer structures are required for the field of photonics and spintronics, but also for the development of next generation high power devices involving boron doping. The fabrication of diamond structures with abrupt interfaces such as superlattices and quantum wells has been recently improved. A very accurate characterization is then essential even though the analysis of such structures is arduous and challenging. SIMS analyses are commonly used to obtain depth profiles of dopants. However, below 10 nm in thickness, SIMS induced ion mixing effects which are no longer negligible. Then the raw SIMS profile might differ from the real dopant profile. In this study, we have analyzed a diamond structure containing a thin boron epilayer, especially synthesized to achieve SIMS analysis on both sides and to overcome the effects of ion mixing. We evidence the ion mixing induced by primary ions. Such a structure is a delta diamond layer, comparable to classical boron-doped delta-layer in silicon. Our results show that the growth of boron-doped delta-layer in diamond is now well controlled in terms of thickness and interfaces.

  15. Magnetostriction of the polycrystalline Fe{sub 80}Al{sub 20} alloy doped with boron

    Energy Technology Data Exchange (ETDEWEB)

    Bormio-Nunes, Cristina, E-mail: cristina@demar.eel.usp.br [Escola de Engenharia de Lorena, Dep. de Eng. de Materiais, Universidade de S.Paulo, Lorena, SP (Brazil); Teodoro dos Santos, Claudio; Botani de Souza Dias, Mateus [Escola de Engenharia de Lorena, Dep. de Eng. de Materiais, Universidade de S.Paulo, Lorena, SP (Brazil); Doerr, Mathias; Granovsky, Sergey; Loewenhaupt, Michael [Institut fuer Festkoerperphysik, TU Dresden, D-01062 Dresden (Germany)

    2012-10-25

    Highlights: Black-Right-Pointing-Pointer Fe{sub 80}Al{sub 20} polycrystalline alloy magnetostriction 40 ppm increased to 80 ppm due to 2% of B doping. Black-Right-Pointing-Pointer B stabilizes {alpha}-FeAl phase and a coexistence of {alpha}-FeAl + Fe{sub 3}Al improves magnetostriction. Black-Right-Pointing-Pointer Presence of Fe{sub 2}B phase causes domain rearrangement revealed by the decrease of the volume magnetostriction. - Abstract: The doping of Fe{sub 80}Al{sub 20} polycrystalline alloy with 2% of boron increased the total magnetostriction twofold compared to a sample without boron. A value close to 80 ppm was achieved at 300 K. The microstructures of the boron-doped alloys show a dendritically solidified matrix with interdendritic {alpha}-FeAl and/or Fe{sub 3}Al and Fe{sub 2}B eutectic between the grains. The XRD analysis reveals an increase in the volume fraction of {alpha}-FeAl and a correspondent decrease of the Fe{sub 3}Al phase volume fraction as the boron content increases. The increase of the volume fraction of this tetragonal Fe{sub 2}B phase in the samples doped with boron causes the decrease of the strong volume magnetostriction that was observed in the alloy without boron. There is some evidence that the improvement of the magnetostriction magnitude due to the addition of boron to the Fe{sub 80}Al{sub 20} alloy could reach the maximal magnetostriction if the 1:1 optimal ratio of the volume fractions of the {alpha}-FeAl and Fe{sub 3}Al phases could be reached.

  16. Fabrication of boron-phosphide neutron detectors

    International Nuclear Information System (INIS)

    Fitzsimmons, M.; Pynn, R.

    1997-01-01

    Boron phosphide is a potentially viable candidate for high neutron flux neutron detectors. The authors have explored chemical vapor deposition methods to produce such detectors and have not been able to produce good boron phosphide coatings on silicon carbide substrates. However, semi-conducting quality films have been produced. Further testing is required

  17. New techniques for producing thin boron films

    International Nuclear Information System (INIS)

    Thomas, G.E.

    1988-01-01

    A review will be presented of methods for producing thin boron films using an electron gun. Previous papers have had the problem of spattering of the boron source during the evaporation. Methods for reducing this problem will also be presented. 12 refs., 4 figs

  18. Boron rates for triticale and wheat crops

    Directory of Open Access Journals (Sweden)

    Corrêa Juliano Corulli

    2005-01-01

    Full Text Available No reports are registered on responses to boron fertilization nutrient deficiency and toxicity in triticale crops. The aim of this study was to evaluate triticale response to different rates of boron in comparison to wheat in an hapludox with initial boron level at 0.08 mg dm-3 4 4 factorial design trial completely randomized blocks design (n = 4. Boron rates were 0; 0.62; 1.24 and 1.86 mg dm-3; triticale cultivars were IAC 3, BR 4 and BR 53 and IAPAR 38 wheat crop was used for comparison. The wheat (IAPAR 38 crop presented the highest boron absorption level of all. Among triticale cultivars, the most responsive was IAC 53, presenting similar characteristics to wheat, followed by BR 4; these two crops are considered tolerant to higher boron rates in soil. Regarding to BR 53, no absorption effect was observed, and the cultivars was sensitive to boron toxicity. Absorption responses differed for each genotype. That makes it possible to choose and use the best-adapted plants to soils with different boron rates.

  19. Hot flow behavior of boron microalloyed steels

    International Nuclear Information System (INIS)

    Lopez-Chipres, E.; Mejia, I.; Maldonado, C.; Bedolla-Jacuinde, A.; El-Wahabi, M.; Cabrera, J.M.

    2008-01-01

    This research work studies the effect of boron contents on the hot flow behavior of boron microalloyed steels. For this purpose, uniaxial hot-compression tests were carried out in a low carbon steel microalloyed with four different amounts of boron over a wide range of temperatures (950, 1000, 1050 and 1100 deg. C) and constant true strain rates (10 -3 , 10 -2 and 10 -1 s -1 ). Experimental results revealed that both peak stress and peak strain tend to decrease as boron content increases, which indicates that boron additions have a solid solution softening effect. Likewise, the flow curves show a delaying effect on the kinetics of dynamic recrystallization (DRX) when increasing boron content. Deformed microstructures show a finer austenitic grain size in the steel with higher boron content (grain refinement effect). Results are discussed in terms of boron segregation towards austenitic grain boundaries during plastic deformation, which increases the movement of dislocations, enhances the grain boundary cohesion and modificates the grain boundary structure

  20. Elastic modulus and fracture of boron carbide

    International Nuclear Information System (INIS)

    Hollenberg, G.W.; Walther, G.

    1978-12-01

    The elastic modulus of hot-pressed boron carbide with 1 to 15% porosity was measured at room temperature. K/sub IC/ values were determined for the same porosity range at 500 0 C by the double torsion technique. The critical stress intensity factor of boron carbide with 8% porosity was evaluated from 25 to 1200 0 C

  1. Multi-dimensional boron transport modeling in subchannel approach: Part I. Model selection, implementation and verification of COBRA-TF boron tracking model

    Energy Technology Data Exchange (ETDEWEB)

    Ozdemir, Ozkan Emre, E-mail: ozdemir@psu.edu [Department of Mechanical and Nuclear Engineering, The Pennsylvania State University, University Park, PA 16802 (United States); Avramova, Maria N., E-mail: mna109@psu.edu [Department of Mechanical and Nuclear Engineering, The Pennsylvania State University, University Park, PA 16802 (United States); Sato, Kenya, E-mail: kenya_sato@mhi.co.jp [Mitsubishi Heavy Industries (MHI), Kobe (Japan)

    2014-10-15

    Highlights: ► Implementation of multidimensional boron transport model in a subchannel approach. ► Studies on cross flow mechanism, heat transfer and lateral pressure drop effects. ► Verification of the implemented model via code-to-code comparison with CFD code. - Abstract: The risk of reflux condensation especially during a Small Break Loss Of Coolant Accident (SB-LOCA) and the complications of tracking the boron concentration experimentally inside the primary coolant system have stimulated and subsequently have been a focus of many computational studies on boron tracking simulations in nuclear reactors. This paper presents the development and implementation of a multidimensional boron transport model with Modified Godunov Scheme within a thermal-hydraulic code based on a subchannel approach. The cross flow mechanism in multiple-subchannel rod bundle geometry as well as the heat transfer and lateral pressure drop effects are considered in the performed studies on simulations of deboration and boration cases. The Pennsylvania State University (PSU) version of the COBRA-TF (CTF) code was chosen for the implementation of three different boron tracking models: First Order Accurate Upwind Difference Scheme, Second Order Accurate Godunov Scheme, and Modified Godunov Scheme. Based on the performed nodalization sensitivity studies, the Modified Godunov Scheme approach with a physical diffusion term was determined to provide the best solution in terms of precision and accuracy. As a part of the verification and validation activities, a code-to-code comparison was carried out with the STAR-CD computational fluid dynamics (CFD) code and presented here. The objective of this study was two-fold: (1) to verify the accuracy of the newly developed CTF boron tracking model against CFD calculations; and (2) to investigate its numerical advantages as compared to other thermal-hydraulics codes.

  2. Boron isotopic enrichment by displacement chromatography

    International Nuclear Information System (INIS)

    Mohapatra, K.K.; Bose, Arun

    2014-01-01

    10 B enriched boron is used in applications requiring high volumetric neutron absorption (absorption cross section- 3837 barn for thermal and 1 barn for 1 MeV fast neutron). It is used in fast breeder reactor (as control rod material), in neutron counter, in Boron Neutron Capture Therapy etc. Owing to very small separation factor, boron isotopic enrichment is a complex process requiring large number of separation stages. Heavy Water Board has ventured in industrial scale production of 10 B enriched boron using Exchange Distillation Process as well as Ion Displacement Chromatography Process. Ion Displacement Chromatography process is used in Boron Enrichment Plant at HWP, Manuguru. It is based on isotopic exchange between borate ions (B(OH) 4 - ) on anion exchange resin and boric acid passing through resin. The isotopic exchange takes place due to difference in zero point energy of 10 B and 11 B

  3. XPS analysis of boron doped heterofullerenes

    Energy Technology Data Exchange (ETDEWEB)

    Schnyder, B; Koetz, R [Paul Scherrer Inst. (PSI), Villigen (Switzerland); Muhr, H J; Nesper, R [ETH Zurich, Zurich (Switzerland)

    1997-06-01

    Boron heterofullerenes were generated through arc-evaporation of doped graphite rods in a helium atmosphere. According to mass spectrometric analysis only mono-substituted fullerenes like C{sub 59}B, C{sub 69}B and higher homologues together with a large fraction of higher undoped fullerenes were extracted and enriched when pyridine was used as the solvent. XPS analysis of the extracts indicated the presence of two boron species with significantly different binding energies. One peak was assigned to borid acid. The second one corresponds to boron in the fullerene cage, which is mainly C{sub 59}B, according to the mass spectrum. This boron is in a somewhat higher oxidation state than that of ordinary boron-carbon compounds. The reported synthesis and extraction procedure opens a viable route for production of macroscopic amounts of these compounds. (author) 2 figs., 1 tab., 7 refs.

  4. Adsorption of sugars on Al- and Ga-doped boron nitride surfaces: A computational study

    Energy Technology Data Exchange (ETDEWEB)

    Darwish, Ahmed A. [Center for Nanotechnology, Zewail City of Science and Technology, Giza 12588 (Egypt); Department of Nuclear and Radiation Engineering, Faculty of Engineering, Alexandria University, Alexandria (Egypt); Fadlallah, Mohamed M. [Center for Fundamental Physics, Zewail City of Science and Technology, Giza 12588 (Egypt); Department of Physics, Faculty of Science, Benha University, Benha (Egypt); Badawi, Ashraf [Center for Nanotechnology, Zewail City of Science and Technology, Giza 12588 (Egypt); Maarouf, Ahmed A., E-mail: ahmed.maarouf@egnc.gov.eg [Center for Fundamental Physics, Zewail City of Science and Technology, Giza 12588 (Egypt); Egypt Nanotechnology Center & Department of Physics, Faculty of Science, Cairo University, Giza 12613 (Egypt)

    2016-07-30

    Highlights: • Doping boron nitride sheets with aluminum or gallium atoms significantly enhances their molecular adsorption properties. • Adsorption of glucose or glucosamine on Al- and Ga-doped boron nitride sheets changes the band gap. • Doping concentration changes the bad gap, but has a minor effect on the adsorption energy. - Abstract: Molecular adsorption on surfaces is a key element for many applications, including sensing and catalysis. Non-invasive sugar sensing has been an active area of research due to its importance to diabetes care. The adsorption of sugars on a template surface study is at the heart of matter. Here, we study doped hexagonal boron nitride sheets (h-BNNs) as adsorbing and sensing template for glucose and glucosamine. Using first principles calculations, we find that the adsorption of glucose and glucosamine on h-BNNs is significantly enhanced by the substitutional doping of the sheet with Al and Ga. Including long range van der Waals corrections gives adsorption energies of about 2 eV. In addition to the charge transfer occurring between glucose and the Al/Ga-doped BN sheets, the adsorption alters the size of the band gap, allowing for optical detection of adsorption. We also find that Al-doped boron nitride sheet is better than Ga-doped boron nitride sheet to enhance the adsorption energy of glucose and glucosamine. The results of our work can be potentially utilized when designing support templates for glucose and glucosamine.

  5. Boron effect on the microstructure of 9% Cr ferritic–martensitic steels

    International Nuclear Information System (INIS)

    Klimenkov, M.; Materna-Morris, E.; Möslang, A.

    2015-01-01

    Highlights: • Detailed TEM characterization of BN, M 23 C 6 , VN and TaC precipitates in B-alloyed EUROFER97. • Determination of B content influence on density and composition of M 23 C 6 and MX precipitates and herewith on microstructure. • α-Al 2 O 3 –BN–TaC–VN precipitation sequence of different phases during cooling was proposed. • Decreasing of thermal stability of microstructure with boron content was measured. - Abstract: The microstructure of reduces-activation 9Cr–WTaV steel alloyed with 83 and 1160 wt. ppm 10 B was detailed analysed using transmission electron microscopy. The influence of boron content on the precipitation behaviour of M 23 C 6 and MX (VN and TaC) phases and, hence, on the formation process of steel’s grain and lath structure was studied. VN precipitates, which play an important role in the stabilisation of the lath structure, exhibit most sensitive reaction on presence of boron. Their spatial density significantly reduces in the alloy with 83 ppm boron. In the steel with 1160 wt. ppm boron, no formation of VN was detected, whereas TaC particles precipitate at the lath and grain boundaries. These changes in the structure stabilisation mechanism lead to an increasing lath width and a decreasing thermal stability of laths and grains. Analytical investigations of several BN particles reveal their complex multi-phase structure and allow conclusions to be drawn with respect to their precipitation sequence

  6. Boron-doped MnO{sub 2}/carbon fiber composite electrode for supercapacitor

    Energy Technology Data Exchange (ETDEWEB)

    Chi, Hong Zhong, E-mail: hzchi@hdu.edu.cn [College of Materials and Environmental Engineering, Hangzhou Dianzi University, Hangzhou 310018 (China); Zhu, Hongjie [College of Materials and Environmental Engineering, Hangzhou Dianzi University, Hangzhou 310018 (China); Gao, Linhui [Center of Materials Engineering, Zhejiang Sci-Tech University, Hangzhou 310018 (China)

    2015-10-05

    Highlights: • Interstitial ion in MnO{sub 2} lattice. • Porous film composed by interlocking worm-like nanostructure. • Boron-doped birnessite-type MnO{sub 2}/carbon fiber composite electrode. • Enhanced capacitive properties through nonmetal element doping. - Abstract: The boron-doped MnO{sub 2}/carbon fiber composite electrode has been prepared via in situ redox reaction between potassium permanganate and carbon fibers in the presence of boric acid. The addition of boron as dopant results in the increase of growth-rate of MnO{sub 2} crystal and the formation of worm-like nanostructure. Based on the analysis of binding energy, element boron incorporates into the MnO{sub 2} lattice through interstitial mode. The doped electrode with porous framework is beneficial to pseudocapacitive reaction and surface charge storage, leading to higher specific capacitance and superior rate capability. After experienced 1000 cycles, the boron-doped MnO{sub 2} still retain a higher specific capacitance by about 80% of its initial value. The fall in capacitance is blamed to be the combination of the formation of soluble Mn{sup 2+} and the absence of active site on the outer surface.

  7. Cathodoluminescence of cubic boron nitride

    International Nuclear Information System (INIS)

    Tkachev, V.D.; Shipilo, V.B.; Zajtsev, A.M.

    1985-01-01

    Three optically active defects are detected in mono- and polycrystal cubic boron nitride (β-BN). Analysis of intensity of temperature dependences, halfwidth and energy shift of 1.76 eV narrow phononless line (center GC-1) makes it possible to interprete the observed cathodoluminescence spectra an optical analog of the Moessbaner effect. Comparison of the obtained results with the known data for diamond monocrystals makes it possible to suggest that the detected center GC-1 is a nitrogen vacancy . The conclusion, concerning the Moessbauer optical spectra application, is made to analyze structural perfection of β-BN crystal lattice

  8. Boron enrichment in martian clay.

    Directory of Open Access Journals (Sweden)

    James D Stephenson

    Full Text Available We have detected a concentration of boron in martian clay far in excess of that in any previously reported extra-terrestrial object. This enrichment indicates that the chemistry necessary for the formation of ribose, a key component of RNA, could have existed on Mars since the formation of early clay deposits, contemporary to the emergence of life on Earth. Given the greater similarity of Earth and Mars early in their geological history, and the extensive disruption of Earth's earliest mineralogy by plate tectonics, we suggest that the conditions for prebiotic ribose synthesis may be better understood by further Mars exploration.

  9. Exoplanets and Multiverses (Abstract)

    Science.gov (United States)

    Trimble, V.

    2016-12-01

    (Abstract only) To the ancients, the Earth was the Universe, of a size to be crossed by a god in a day, by boat or chariot, and by humans in a lifetime. Thus an exoplanet would have been a multiverse. The ideas gradually separated over centuries, with gradual acceptance of a sun-centered solar system, the stars as suns likely to have their own planets, other galaxies beyond the Milky Way, and so forth. And whenever the community divided between "just one' of anything versus "many," the "manies" have won. Discoveries beginning in 1991 and 1995 have gradually led to a battalion or two of planets orbiting other stars, very few like our own little family, and to moderately serious consideration of even larger numbers of other universes, again very few like our own. I'm betting, however, on habitable (though not necessarily inhabited) exoplanets to be found, and habitable (though again not necessarily inhabited) universes. Only the former will yield pretty pictures.

  10. SENSE 2010, Abstracts

    International Nuclear Information System (INIS)

    Lumsden, M.D.; Argyriou, D.N.; Inosov, D.

    2012-01-01

    The microscopic origin of unconventional superconductivity continues to attract the attention of the condensed matter community. Whereas rare-earth / actinide-based intermetallic and copper oxide-based high temperature superconductors are studied for more than twenty years, the iron-based superconductors have been in the focus of interest since their recent discovery. Inelastic neutron scattering experiments have been of particular importance for the understanding of the magnetic and superconducting properties of these compounds. With its 29 talks and 14 posters the workshop provided a forum for the 71 registered participants to review and discuss experimental achievements, recognize the observed synergy and differences as well as discuss theoretical efforts to identify the symmetry of the superconducting order parameter in addition to the coupling mechanisms of the Cooper pairs. The workshop covered different topics relevant for the study of unconventional superconductivity. Magnetization and lattice dynamics such as spin resonances, phonons, magnetic and other excitations as studied by spectroscopic methods were presented. Investigations of (doping, pressure and magnetic field dependent) phase diagrams, electronic states as well as vortex physics by the various diffraction techniques were also addressed. This document gathers only the abstracts of the papers. (authors)

  11. Book of Abstracts

    International Nuclear Information System (INIS)

    2013-06-01

    ANIMMA 2013 is the third of a series of conferences devoted to endorsing and promoting scientific and technical activities based on nuclear instrumentation and measurements. The main objective of ANIMMA conference is to unite the various scientific communities not only involved in nuclear instrumentation and measurements, but also in nuclear medicine and radiation. The conference is all about getting scientists, engineers and the industry to meet, exchange cultures and identify new scientific and technical prospects to help overcome both current and future unresolved issues. The conference provides scientists and engineers with a veritable opportunity to compare their latest research and development in different areas: physics, nuclear energy, nuclear fuel cycle, safety, security, future energies (GEN III+, GENIV, ITER, ...). The conference topics include instrumentation and measurement methods for: Fundamental physics; Fusion diagnostics and technology; Nuclear power reactors; Research reactors; Nuclear fuel cycle; Decommissioning, dismantling and remote handling; Safeguards, homeland security; Severe accident monitoring; Environmental and medical sciences; Education, training and outreach. This document brings together the abstracts of the presentations. Each presentation (full paper) is analysed separately and entered in INIS

  12. Stellar Presentations (Abstract)

    Science.gov (United States)

    Young, D.

    2015-12-01

    (Abstract only) The AAVSO is in the process of expanding its education, outreach and speakers bureau program. powerpoint presentations prepared for specific target audiences such as AAVSO members, educators, students, the general public, and Science Olympiad teams, coaches, event supervisors, and state directors will be available online for members to use. The presentations range from specific and general content relating to stellar evolution and variable stars to specific activities for a workshop environment. A presentation—even with a general topic—that works for high school students will not work for educators, Science Olympiad teams, or the general public. Each audience is unique and requires a different approach. The current environment necessitates presentations that are captivating for a younger generation that is embedded in a highly visual and sound-bite world of social media, twitter and U-Tube, and mobile devices. For educators, presentations and workshops for themselves and their students must support the Next Generation Science Standards (NGSS), the Common Core Content Standards, and the Science Technology, Engineering and Mathematics (STEM) initiative. Current best practices for developing relevant and engaging powerpoint presentations to deliver information to a variety of targeted audiences will be presented along with several examples.

  13. Automated Supernova Discovery (Abstract)

    Science.gov (United States)

    Post, R. S.

    2015-12-01

    (Abstract only) We are developing a system of robotic telescopes for automatic recognition of Supernovas as well as other transient events in collaboration with the Puckett Supernova Search Team. At the SAS2014 meeting, the discovery program, SNARE, was first described. Since then, it has been continuously improved to handle searches under a wide variety of atmospheric conditions. Currently, two telescopes are used to build a reference library while searching for PSN with a partial library. Since data is taken every night without clouds, we must deal with varying atmospheric and high background illumination from the moon. Software is configured to identify a PSN, reshoot for verification with options to change the run plan to acquire photometric or spectrographic data. The telescopes are 24-inch CDK24, with Alta U230 cameras, one in CA and one in NM. Images and run plans are sent between sites so the CA telescope can search while photometry is done in NM. Our goal is to find bright PSNs with magnitude 17.5 or less which is the limit of our planned spectroscopy. We present results from our first automated PSN discoveries and plans for PSN data acquisition.

  14. Chemistry and technology of boron and its compounds

    International Nuclear Information System (INIS)

    Zhigach, A.F.; Parfenov, B.P.; Svitsyn, R.A.

    1995-01-01

    The results of research dealing with development of technologies of boron trichloride, boron hydride, aminoderivative boron hydrides, metal borohydrides, carboranes, carborane-containing polymers, carried out at the institute of organoelemental compounds, are presented. Physicochemical properties of the compounds have been studied and analytical methods have been developed. Data on toxicity and fire hazard of boron compounds are provided

  15. Analysis of boron nitride by flame spectrometry methods

    International Nuclear Information System (INIS)

    Telegin, G.F.; Chapysheva, G.Ya.; Shilkina, N.N.

    1989-01-01

    A rapid method has been developed for determination of free and total boron contents as well as trace impurities in boron nitride by using autoclave sample decomposition followed by atomic emission and atomic absorption determination. The relative standard deviation is not greater than 0.03 in the determination of free boron 0.012 in the determination of total boron content

  16. Abstraction of Drift Seepage

    International Nuclear Information System (INIS)

    J.T. Birkholzer

    2004-01-01

    This model report documents the abstraction of drift seepage, conducted to provide seepage-relevant parameters and their probability distributions for use in Total System Performance Assessment for License Application (TSPA-LA). Drift seepage refers to the flow of liquid water into waste emplacement drifts. Water that seeps into drifts may contact waste packages and potentially mobilize radionuclides, and may result in advective transport of radionuclides through breached waste packages [''Risk Information to Support Prioritization of Performance Assessment Models'' (BSC 2003 [DIRS 168796], Section 3.3.2)]. The unsaturated rock layers overlying and hosting the repository form a natural barrier that reduces the amount of water entering emplacement drifts by natural subsurface processes. For example, drift seepage is limited by the capillary barrier forming at the drift crown, which decreases or even eliminates water flow from the unsaturated fractured rock into the drift. During the first few hundred years after waste emplacement, when above-boiling rock temperatures will develop as a result of heat generated by the decay of the radioactive waste, vaporization of percolation water is an additional factor limiting seepage. Estimating the effectiveness of these natural barrier capabilities and predicting the amount of seepage into drifts is an important aspect of assessing the performance of the repository. The TSPA-LA therefore includes a seepage component that calculates the amount of seepage into drifts [''Total System Performance Assessment (TSPA) Model/Analysis for the License Application'' (BSC 2004 [DIRS 168504], Section 6.3.3.1)]. The TSPA-LA calculation is performed with a probabilistic approach that accounts for the spatial and temporal variability and inherent uncertainty of seepage-relevant properties and processes. Results are used for subsequent TSPA-LA components that may handle, for example, waste package corrosion or radionuclide transport

  17. Book of abstracts

    International Nuclear Information System (INIS)

    1987-01-01

    The document contains abstracts of 24 review papers, 24 invited papers, 24 oral contributions and 120 posters. 10 review papers summarize the status of laser fusion research and progress in high-power laser facilities in major world laboratories. Four papers review research programs (laser-matter interaction studies and X-ray source development) based on KrF laser systems. Other review papers discuss the problems of laser energy conversion into X-rays in laser-heated cavities, X-ray lasing at shorter wavelengths, optimization of targets for inertial fusion. Two review papers are devoted to light ion fusion. The subjects of most invited papers are special problems of current laser plasma research, such as hot electron generation, nonlinear resonance absorption, energy accumulation limits, pellet ignition, conversion of laser light into X-rays, high-pressure plasma generation. Three invited papers review laser plasma research in Czechoslovakia, Poland and Spain. One paper suggests a new method of producing muonic superdense matter. The remaining inivited papers deal with the progress in XUV lasers and with laser plasma applications for further laser development. Of the papers accepted for oral presentation 12 papers discuss various problems of laser-plasma interaction; 4 papers deal with laser targets, 4 papers with laser-initiated X-ray sources, 3 papers with the diagnostics of laser-produced plasma. The last oral contribution presents the main principles of the excimer laser theory. The largest group of posters is related to laser-plasma interaction and energy absorption problems, to laser-target interaction and various methods of laser plasma diagnostics. The other posters deal with plasma applications in laser development, plasma mirrors, Brillouin and Raman scattering, X-ray emission, harmonic generation, electron acceleration, production of high-Z plasmas and other related problems. (J.U.)

  18. Study of ceramic mixed boron element as a neutron shielding

    International Nuclear Information System (INIS)

    Ismail Mustapha; Mohd Reusmaazran Yusof; Md Fakarudin Ab Rahman; Nor Paiza Mohamad Hasan; Samihah Mustaffha; Yusof Abdullah; Mohamad Rabaie Shari; Airwan Affandi Mahmood; Nurliyana Abdullah; Hearie Hassan

    2012-01-01

    Shielding upon radiation should not be underestimated as it can causes hazard to health. Precautions on the released of radioactive materials should be well concerned and considered. Therefore, the combination of ceramic and boron make them very useful for shielding purpose in areas of low and intermediate neutron. A six grades of ceramic tile have been produced namely IMN05 - 5 % boron, IMN06 - 6 % boron, IMN07 - 7 % boron, IMN08 - 8 % boron, IMN09 - 9 % boron, IMN10 - 10 % boron from mixing, press and sintered process. Boron is a material that capable of absorbing and capturing neutron, so that neutron and gamma test were conducted to analyze the effectiveness of boron material in combination with ceramic as shielding. From the finding, percent reduction number of count per minute shows the ceramic tiles are capable to capture neutron. Apart from all the percentage of boron used, 10 % is the most effective shields since the percent reduction indicating greater neutron captured increased. (author)

  19. Boron-Loaded Silicone Rubber Scintillators

    Energy Technology Data Exchange (ETDEWEB)

    Bell, Z.W.; Maya, L.; Brown, G.M.; Sloop, F.V.Jr

    2003-05-12

    Silicone rubber received attention as an alternative to polyvinyltoluene in applications in which the scintillator is exposed to high doses because of the increased resistance of the rubber to the formation of blue-absorbing color centers. Work by Bowen, et al., and Harmon, et al., demonstrated their properties under gamma/x-ray irradiation, and Bell, et al. have shown their response to thermal neutrons. This last work, however, provided an example of a silicone in which both the boron and the scintillator were contained in the rubber as solutes, a formulation which led to the precipitation of solids and sublimation of the boron component. In the present work we describe a scintillator in which the boron is chemically bonded to the siloxane and so avoids the problem of precipitation and loss of boron to sublimation. Material containing up to 18% boron, by weight, was prepared, mounted on photomultipliers, and exposed to both neutron and gamma fluxes. Pulse height spectra showing the neutron and photon response were obtained, and although the light output was found to be much poorer than from samples in which boron was dissolved, the higher boron concentrations enabled essentially 100% neutron absorption in only a few millimeters' thickness of rubber.

  20. Density separation of boron particles. Final report

    International Nuclear Information System (INIS)

    Smith, R.M.

    1980-04-01

    A density distribution much broader than expected was observed in lots of natural boron powder supplied by two different sources. The material in both lots was found to have a rhombohedral crystal structure, and the only other parameters which seemed to account for such a distribution were impurities within the crystal structure and varying isotopic ratios. A separation technique was established to isolate boron particles in narrow densty ranges. The isolated fractions were subsequently analyzed for B 10 and total boron content in an effort to determine whether selective isotopic enrichment and nonhomogeneous impurity distribution were the causes for the broad density distribution of the boron powders. It was found that although the B 10 content remained nearly constant around 18%, the total boron content varied from 37.5 to 98.7%. One of the lots also was found to contain an apparently high level of alpha rhombohedral boron which broadened the density distribution considerably. During this work, a capability for removing boron particles containing gross amounts of impurities and, thereby, improving the overall purity of the remaining material was developed. In addition, the separation technique used in this study apparently isolated particles with alpha and beta rhombohedral crystal structures, although the only supporting evidence is density data

  1. Cell cycle dependence of boron uptake in various boron compounds used for neutron capture therapy

    International Nuclear Information System (INIS)

    Yoshida, F.; Matsumura, A.; Shibata, Y.; Yamamoto, T.; Nose, T.; Okumura, M.

    2000-01-01

    In neutron capture therapy, it is important that the tumor take boron in selectively. Furthermore, it is ideal when the uptake is equal in each tumor cell. Some indirect proof of differences in boron uptake among neoplastic cell cycles has been documented. However, no investigation has yet measured boron uptake directly. Using flow cytometry, in the present study cells were sorted by G0/G1 phase and G2/M phase, and the boron concentration of each fraction was measured with inductively coupled plasma-atomic emission spectroscopy (ICP-AES). The results were that BSH (sodiumborocaptate) and BPA (p-boronophenylalanine) had higher rates of boron uptake in the G2/M group than in the G0/G1 group. However, in BPA the difference was more prominent, which revealed a 2.2-3.3 times higher uptake of boron in the G2/M group than in the G0/G1 group. (author)

  2. The determination of boron and carbon in reactor grade boron carbide

    International Nuclear Information System (INIS)

    Crossley, D.; Wood, A.J.; McInnes, C.A.J.; Jones, I.G.

    1978-09-01

    The sealed tube method of dissolution at high temperature and pressure has been successfully applied in the analysis of reactor grade boron carbide for the determination of boron. A 50 mg sample of boron carbide is completely dissolved by heating with concentrated nitric acid in a sealed tube at 300 0 C. The boron content of the resultant sample solution is determined by the mannitol potentiometric titration method. The precision of the method for the determination of 2.5 mg of boron using the Harwell automatic potentiometric titrator is 0.2% (coefficient of variation). The carbon content of a boron carbide sample is determined by combustion of the sample at 1050 0 C in a stream of oxygen using vanadium pentoxide to ensure the complete oxidation of the sample. The carbon dioxide produced from the sample is measured manometrically and the precision of the method for the determination of 4 mg of carbon is 0.4% (coefficient of variation). (author)

  3. Hot ductility behavior of a low carbon advanced high strength steel (AHSS) microalloyed with boron

    International Nuclear Information System (INIS)

    Mejia, I.; Bedolla-Jacuinde, A.; Maldonado, C.; Cabrera, J.M.

    2011-01-01

    Research highlights: → Effect of boron on the hot ductility behavior of a low carbon NiCrVCu AHSS. → Boron addition of 117 ppm improves hot ductility over 100% in terms of RA. → Hot ductility improvement is associated with segregation/precipitation of boron. → Typical hot ductility recovery at lower temperatures does not appear in this steel. → Hot ductility loss is associated with precipitates/inclusions coupled with voids. - Abstract: The current study analyses the influence of boron addition on the hot ductility of a low carbon advanced high strength NiCrVCu steel. For this purpose hot tensile tests were carried out at different temperatures (650, 750, 800, 900 and 1000 deg. C) at a constant true strain rate of 0.001 s -1 . Experimental results showed a substantial improvement in hot ductility for the low carbon advanced high strength steel when microalloyed with boron compared with that without boron addition. Nevertheless, both steels showed poor ductility when tested at the lowest temperatures (650, 750 and 800 deg. C), and such behavior is associated to the precipitation of vanadium carbides/nitrides and inclusions, particularly MnS and CuS particles. The fracture mode of the low carbon advanced high strength steel microalloyed with boron seems to be more ductile than the steel without boron addition. Furthermore, the fracture surfaces of specimens tested at temperatures showing the highest ductility (900 and 1000 deg. C) indicate that the fracture mode is a result of ductile failure, while in the region of poor ductility the fracture mode is of the ductile-brittle type failure. It was shown that precipitates and/or inclusions coupled with voids play a meaningful role on the crack nucleation mechanism which in turn causes a hot ductility loss. Likewise, dynamic recrystallization (DRX) which always results in restoration of ductility only occurs in the range from 900 to 1000 deg. C. Results are discussed in terms of boron segregation towards

  4. Hot ductility behavior of a low carbon advanced high strength steel (AHSS) microalloyed with boron

    Energy Technology Data Exchange (ETDEWEB)

    Mejia, I., E-mail: imejia@umich.mx [Instituto de Investigaciones Metalurgicas, Universidad Michoacana de San Nicolas de Hidalgo, Edificio ' U' , Ciudad Universitaria, 58066 Morelia, Michoacan (Mexico); Bedolla-Jacuinde, A.; Maldonado, C. [Instituto de Investigaciones Metalurgicas, Universidad Michoacana de San Nicolas de Hidalgo, Edificio ' U' , Ciudad Universitaria, 58066 Morelia, Michoacan (Mexico); Cabrera, J.M. [Departament de Ciencia dels Materials i Enginyeria Metal.lurgica, ETSEIB - Universitat Politecnica de Catalunya, Av. Diagonal 647, 08028 Barcelona (Spain); Fundacio CTM Centre Tecnologic, Av. de las Bases de Manresa 1, 08240 Manresa (Spain)

    2011-05-25

    Research highlights: {yields} Effect of boron on the hot ductility behavior of a low carbon NiCrVCu AHSS. {yields} Boron addition of 117 ppm improves hot ductility over 100% in terms of RA. {yields} Hot ductility improvement is associated with segregation/precipitation of boron. {yields} Typical hot ductility recovery at lower temperatures does not appear in this steel. {yields} Hot ductility loss is associated with precipitates/inclusions coupled with voids. - Abstract: The current study analyses the influence of boron addition on the hot ductility of a low carbon advanced high strength NiCrVCu steel. For this purpose hot tensile tests were carried out at different temperatures (650, 750, 800, 900 and 1000 deg. C) at a constant true strain rate of 0.001 s{sup -1}. Experimental results showed a substantial improvement in hot ductility for the low carbon advanced high strength steel when microalloyed with boron compared with that without boron addition. Nevertheless, both steels showed poor ductility when tested at the lowest temperatures (650, 750 and 800 deg. C), and such behavior is associated to the precipitation of vanadium carbides/nitrides and inclusions, particularly MnS and CuS particles. The fracture mode of the low carbon advanced high strength steel microalloyed with boron seems to be more ductile than the steel without boron addition. Furthermore, the fracture surfaces of specimens tested at temperatures showing the highest ductility (900 and 1000 deg. C) indicate that the fracture mode is a result of ductile failure, while in the region of poor ductility the fracture mode is of the ductile-brittle type failure. It was shown that precipitates and/or inclusions coupled with voids play a meaningful role on the crack nucleation mechanism which in turn causes a hot ductility loss. Likewise, dynamic recrystallization (DRX) which always results in restoration of ductility only occurs in the range from 900 to 1000 deg. C. Results are discussed in terms of

  5. Developments in boron magnetic resonance imaging (MRI)

    International Nuclear Information System (INIS)

    Schweizer, M.

    1995-01-01

    This report summarizes progress during the past year on maturing Boron-11 magnetic resonance imaging (MRI) methodology for noninvasive determination of BNCT agents (BSH) spatially in time. Three major areas are excerpted: (1) Boron-11 MRI of BSH distributions in a canine intracranial tumor model and the first human glioblastoma patient, (2) whole body Boron-11 MRI of BSH pharmacokinetics in a rat flank tumor model, and (3) penetration of gadolinium salts through the BBB as a function of tumor growth in the canine brain

  6. Advance Organizers: Concret Versus Abstract.

    Science.gov (United States)

    Corkill, Alice J.; And Others

    1988-01-01

    Two experiments examined the relative effects of concrete and abstract advance organizers on students' memory for subsequent prose. Results of the experiments are discussed in terms of the memorability, familiarity, and visualizability of concrete and abstract verbal materials. (JD)

  7. Characterization of boron tolerant bacteria isolated from a fly ash dumping site for bacterial boron remediation.

    Science.gov (United States)

    Edward Raja, Chellaiah; Omine, Kiyoshi

    2013-08-01

    Boron is an essential micronutrient for plants, but can above certain concentrations be toxic to living organisms. A major environmental concern is the removal of boron from contaminated water and fly ash. For this purpose, the samples were collected from a fly ash dumping site, Nagasaki prefecture, Japan. The chemical characteristics and heavy metal concentration of the samples were performed by X-ray fluorescent analysis and leaching test. For bacterial analysis, samples were collected in sterile plastic sheets and isolation was carried out by serial dilution method. The boron tolerant isolates that showed values of maximum inhibitory concentration toward boron ranging from 100 to 260 mM level were screened. Based on 16S rRNA sequencing and phylogenetic analysis, the isolates were most closely related to the genera Bacillus, Lysinibacillus, Microbacterium and Ralstonia. The boron tolerance of these strains was also associated with resistant to several heavy metals, such as As (III), Cr (VI), Cd, Cu, Pb, Ni, Se (III) and Zn. Indeed, these strains were arsenic oxidizing bacteria confirmed by silver nitrate test. These strains exhibited their salt resistances ranging from 4 to 15 % were determined in Trypticase soy agar medium. The boron tolerant strains were capable of removing 0.1-2.0 and 2.7-3.7 mg l(-1) boron from the medium and fly ash at 168 h. Thus, we have successfully identified the boron tolerant and removal bacteria from a fly ash dumping site for boron remediation.

  8. Investigation of boron extraction process with aid magnesium hydroxide from mother liquor of boron production

    International Nuclear Information System (INIS)

    Balapanova, B.S.; Zhajmina, R.E.; Serazetdinov, D.Z.

    1988-01-01

    Conditions of boron - magnesium concentrate preparation from mother liquor by coprecipitation of borate - ions by magnesium hydroxide are investigated. It is shown that boron - magnesium concentrate and products of its heat treatment at 100 - 500 deg C in water are dissolved partially, and in ammonium citrate - practically completely. Suppositions are made on the composition of the product prepared, on the the structure of its crystal lattice and the processes taking place in it during heat treatment. The conclusion is made on the perspectiveness of processing of mother liquor of boron industry for boron - magnesium concentrate

  9. Typesafe Abstractions for Tensor Operations

    OpenAIRE

    Chen, Tongfei

    2017-01-01

    We propose a typesafe abstraction to tensors (i.e. multidimensional arrays) exploiting the type-level programming capabilities of Scala through heterogeneous lists (HList), and showcase typesafe abstractions of common tensor operations and various neural layers such as convolution or recurrent neural networks. This abstraction could lay the foundation of future typesafe deep learning frameworks that runs on Scala/JVM.

  10. Cathodoluminescence of cubic boron nitride

    International Nuclear Information System (INIS)

    Tkachev, V.D.; Shipilo, V.B.; Zaitsev, A.M.

    1985-01-01

    Three types of optically active defect were observed in single-crystal and polycrystalline cubic boron nitride (β-BN). An analysis of the temperature dependences of the intensity, half-width, and energy shift of a narrow zero-phonon line at 1.76 eV (GC-1 center) made it possible to interpret the observed cathodoluminescence spectra as an optical analog of the Moessbauer effect. A comparison of the results obtained in the present study with the available data on diamond single crystals made it possible to identify the observed GC-1 center as a nitrogen vacancy. It was concluded that optical Moessbauer-type spectra can be used to analyze structure defects in the crystal lattice of β-BN

  11. Behaviour of boron in Mandovi estuary (Goa)

    Digital Repository Service at National Institute of Oceanography (India)

    Shirodkar, P.V.; Anand, S.P.

    and alkalinity gave positive correlations with a linear variation. Though the overall behavioural pattern of boron indicated non-conservative nature, it showed a quasi-conservative character during premonsoon and a non-conservative during rest of the seasons...

  12. Internal stress control of boron thin film

    International Nuclear Information System (INIS)

    Satomi, N.; Kitamura, M.; Sasaki, T.; Nishikawa, M.

    1998-01-01

    The occurrence of stress in thin films has led to serious stability problems in practical use. We have investigated the stress in the boron films to find the deposition condition of the boron films with less stress. It was found that the stress in the boron film varies sufficiently from compressive to tensile stress, that is from -1.0 to 1.4 GPa, depending on the evaporation conditions, such as deposition rate and the substrate temperature. Hydrogen ion bombardment resulted in the enhancement of the compressive stress, possibly due to ion peening effect, while under helium ion bombardment, stress relief was observed. The boron film with nearly zero stress was obtained by the evaporation at a deposition rate of 0.5 nm s -1 and substrate temperature of 300 C. (orig.)

  13. Internal stress control of boron thin film

    Energy Technology Data Exchange (ETDEWEB)

    Satomi, N.; Kitamura, M.; Sasaki, T.; Nishikawa, M. [Osaka Univ., Suita (Japan). Graduate Sch. of Eng.

    1998-09-01

    The occurrence of stress in thin films has led to serious stability problems in practical use. We have investigated the stress in the boron films to find the deposition condition of the boron films with less stress. It was found that the stress in the boron film varies sufficiently from compressive to tensile stress, that is from -1.0 to 1.4 GPa, depending on the evaporation conditions, such as deposition rate and the substrate temperature. Hydrogen ion bombardment resulted in the enhancement of the compressive stress, possibly due to ion peening effect, while under helium ion bombardment, stress relief was observed. The boron film with nearly zero stress was obtained by the evaporation at a deposition rate of 0.5 nm s{sup -1} and substrate temperature of 300 C. (orig.) 12 refs.

  14. Determination of boron in amorphous alloys

    Energy Technology Data Exchange (ETDEWEB)

    Grazhulene, S.S.; Grossman, O.V.; Kuntscher, K.K.; Malygina, L.I.; Muller, E.N.; Telegin, G.F.

    1985-10-01

    In the determination of boron in amorphous alloys containingFe, Co, B, Si, Ni, and P having unusal magnetic and electrical properties, precise analysis and rapid analysis are necessary. To improve the metrological properties of the existing procedure, to find a rapid determination of boron in amorphous alloys, and to verify the accuracy of the results, in the present work the optimization of the photometric determination after extraction of the BF/sup -//sub 4/ ion pair with methylene blue has been studied, and a boron determination by flame photometry using selective methylation has been developed. The determination of boron by the flame photometric and spectrophotometric methods is shown. When a highly precise determination is needed, the spectrophotometric procedure can be used. This procedure is distinguished by its labor intensity and duration. When the need for reproducibility is less severe, the rapid flame photometric procedure is best.

  15. Boron adsorption on hematite and clinoptilolite

    International Nuclear Information System (INIS)

    Gainer, G.M.

    1993-01-01

    This thesis describes experiments performed to determine the suitability of boron as a potential reactive tracer for use in saturated-zone C-well reactive tracer studies for the Yucca Mountain Project (YMP). Experiments were performed to identify the prevalent sorption mechanism of boron and to determine adsorption of boron on hematite and clinoptilolite as a function of pH. These minerals are present in the Yucca Mountain tuff in which the C-well studies will be conducted. Evaluation of this sorption mechanism was done by determining the equilibration time of boron-mineral suspensions, by measuring changes in equilibrium to titrations, and by measuring electrophoretic mobility. Experiments were performed with the minerals suspended in NaCl electrolytes of concentrations ranging from 0.1 N NaCl to 0.001 N NaCl. Experimentalconditions included pH values between 3 and 12 and temperature of about 38 degrees C

  16. Boron-isotope fractionation in plants

    Energy Technology Data Exchange (ETDEWEB)

    Marentes, E [Univ. of Guelph, Dept. of Horticultural Science, Guelph, Ontario (Canada); Vanderpool, R A [USDA/ARS Grand Forks Human Nutrition Research Center, Grand Forks, North Dakota (United States); Shelp, B J [Univ. of Guelph, Dept. of Horticultural Science, Guelph, Ontario (Canada)

    1997-10-15

    Naturally-occurring variations in the abundance of stable isotopes of carbon, nitrogen, oxygen, and other elements in plants have been reported and are now used to understand various physiological processes in plants. Boron (B) isotopic variation in several plant species have been documented, but no determination as to whether plants fractionate the stable isotopes of boron, {sup 11}B and {sup 10}B, has been made. Here, we report that plants with differing B requirements (wheat, corn and broccoli) fractionated boron. The whole plant was enriched in {sup 11}B relative to the nutrient solution, and the leaves were enriched in {sup 10}B and the stem in {sup 11}B relative to the xylem sap. Although at present, a mechanistic role for boron in plants is uncertain, potential fractionating mechanisms are discussed. (author)

  17. Boron-isotope fractionation in plants

    International Nuclear Information System (INIS)

    Marentes, E.; Vanderpool, R.A.; Shelp, B.J.

    1997-01-01

    Naturally-occurring variations in the abundance of stable isotopes of carbon, nitrogen, oxygen, and other elements in plants have been reported and are now used to understand various physiological processes in plants. Boron (B) isotopic variation in several plant species have been documented, but no determination as to whether plants fractionate the stable isotopes of boron, 11 B and 10 B, has been made. Here, we report that plants with differing B requirements (wheat, corn and broccoli) fractionated boron. The whole plant was enriched in 11 B relative to the nutrient solution, and the leaves were enriched in 10 B and the stem in 11 B relative to the xylem sap. Although at present, a mechanistic role for boron in plants is uncertain, potential fractionating mechanisms are discussed. (author)

  18. Boron dose determination for BNCT using Fricke and EPR dosimetry

    International Nuclear Information System (INIS)

    Wielopolski, L.; Ciesielski, B.

    1995-01-01

    In Boron Neutron Capture Therapy (BNCT) the dominant dose delivered to the tumor is due to α and 7 Li charged particles resulting from a neutron capture by 10 B and is referred to herein as the boron dose. Boron dose is directly attributable to the following two independent factors, one boron concentration and the neutron capture energy dependent cross section of boron, and two the energy spectrum of the neutrons that interact with boron. The neutron energy distribution at a given point is dictated by the incident neutron energy distribution, the depth in tissue, geometrical factors such as beam size and patient's dimensions. To account for these factors can be accommodated by using Monte Carlo theoretical simulations. However, in conventional experimental BNCT dosimetry, e.g., using TLDs or ionization chambers, it is only possible to estimate the boron dose. To overcome some of the limitations in the conventional dosimetry, modifications in ferrous sulfate dosimetry (Fricke) and Electron Paramagnetic Resonance (EPR) dosimetry in alanine, enable to measure specifically boron dose in a mixed gamma neutron radiation fields. The boron dose, in either of the dosimeters, is obtained as a difference between measurements with boronated and unboronated dosimeters. Since boron participates directly in the measurements, the boron dosimetry reflects the true contribution, integral of the neutron energy spectrum with boron cross section, of the boron dose to the total dose. Both methods are well established and used extensively in dosimetry, they are presented briefly here

  19. Boron-rich oligomers for BNCT

    International Nuclear Information System (INIS)

    Gula, M.; Perleberg, O.; Gabel, D.

    2000-01-01

    The synthesis of two BSH derivatives is described, which can be used for oligomerization in DNA-synthesizers. Synthesis pathways lead to final products in five and six steps, respectively. Because of chirality interesting results were expected. NMR-measurements confirm this expectation. Possible oligomers with high concentrations of boron can be attached to biomolecules. These oligomers can be explored with several imaging methods (EELS, PEM) to determine the lower detection limit of boron with these methods. (author)

  20. Rare earth-iron-boron premanent magnets

    International Nuclear Information System (INIS)

    Ghendehari, M.H.

    1988-01-01

    This patent describes a method for producing rare earth-iron-boron permanent magnets containing added rare earth oxide, comprising the steps of: (a) mixing a particulate alloy containing at least one rare earth metal, iron, and boron with at least one particulate rare earth oxide; (b) aligning magnetic domains of the mixture in a magnetic field; (c) compacting the aligned mixture to form a shape; and (d) sintering the compacted shape

  1. Quantitative analysis of boron by neutron radiography

    International Nuclear Information System (INIS)

    Bayuelken, A.; Boeck, H.; Schachner, H.; Buchberger, T.

    1990-01-01

    The quantitative determination of boron in ores is a long process with chemical analysis techniques. As nuclear techniques like X-ray fluorescence and activation analysis are not applicable for boron, only the neutron radiography technique, using the high neutron absorption cross section of this element, can be applied for quantitative determinations. This paper describes preliminary tests and calibration experiments carried out at a 250 kW TRIGA reactor. (orig.) [de

  2. Discharge cleaning on TFTR after boronization

    International Nuclear Information System (INIS)

    Mueller, D.; Dylla, H.F.; LaMarche, P.H.; Bell, M.G.; Blanchard, W.; Bush, C.E.; Gentile, C.; Hawryluk, R.J.; HIll, K.W.; Janos, A.C.; Jobes, F.C; Owens, D.K.; Pearson, G.; Schivell, J.; Ulrickson, M.A.; Vannoy, C.; Wong, K.L.

    1991-05-01

    At the beginning of the 1990 TFTR experimental run, after replacement of POCO-AXF-5Q graphite tiles on the midplane of the bumper limiter by carbon fiber composite (CFC) tiles and prior to any Pulse Discharge Cleaning (PDC), boronization was performed. Boronization is the deposition of a layer of boron and carbon on the vacuum vessel inner surface by a glow discharge in a diborane, methane and helium mixture. The amount of discharge cleaning required after boronization was substantially reduced compared to that which was needed after previous openings when boronization was not done. Previously, after a major shutdown, about 10 5 low current (∼20 kA) Taylor Discharge Cleaning (TDC) pulses were required before high current (∼400 kA) aggressive Pulse Discharge Cleaning (PDC) pulses could be performed successfully. Aggressive PDC is used to heat the limiters from the vessel bakeout temperature of 150 degrees C to 250 degrees C for a period of several hours. Heating the limiters is important to increase the rate at which water is removed from the carbon limiter tiles. After boronization, the number of required TDC pulses was reduced to <5000. The number of aggressive PDC pulses required was approximately unchanged. 14 refs., 1 tab

  3. Boronization on NSTX using Deuterated Trimethylboron

    International Nuclear Information System (INIS)

    Blanchard, W.R.; Gernhardt, R.C.; Kugel, H.W.; LaMarche, P.H.

    2002-01-01

    Boronization on the National Spherical Torus Experiment (NSTX) has proved to be quite beneficial with increases in confinement and density, and decreases in impurities observed in the plasma. The boron has been applied to the interior surfaces of NSTX, about every 2 to 3 weeks of plasma operation, by producing a glow discharge in the vacuum vessel using deuterated trimethylboron (TMB) in a 10% mixture with helium. Special NSTX requirements restricted the selection of the candidate boronization method to the use of deuterated boron compounds. Deuterated TMB met these requirements, but is a hazardous gas and special care in the execution of the boronization process is required. This paper describes the existing GDC, Gas Injection, and Torus Vacuum Pumping System hardware used for this process, the glow discharge process, and the automated control system that allows for remote operation to maximize both the safety and efficacy of applying the boron coating. The administrative requirements and the detailed procedure for the setup, operation and shutdown of the process are also described

  4. Innovative boron nitride-doped propellants

    Directory of Open Access Journals (Sweden)

    Thelma Manning

    2016-04-01

    Full Text Available The U.S. military has a need for more powerful propellants with balanced/stoichiometric amounts of fuel and oxidants. However, balanced and more powerful propellants lead to accelerated gun barrel erosion and markedly shortened useful barrel life. Boron nitride (BN is an interesting potential additive for propellants that could reduce gun wear effects in advanced propellants (US patent pending 2015-026P. Hexagonal boron nitride is a good lubricant that can provide wear resistance and lower flame temperatures for gun barrels. Further, boron can dope steel, which drastically improves its strength and wear resistance, and can block the formation of softer carbides. A scalable synthesis method for producing boron nitride nano-particles that can be readily dispersed into propellants has been developed. Even dispersion of the nano-particles in a double-base propellant has been demonstrated using a solvent-based processing approach. Stability of a composite propellant with the BN additive was verified. In this paper, results from propellant testing of boron nitride nano-composite propellants are presented, including closed bomb and wear and erosion testing. Detailed characterization of the erosion tester substrates before and after firing was obtained by electron microscopy, inductively coupled plasma and x-ray photoelectron spectroscopy. This promising boron nitride additive shows the ability to improve gun wear and erosion resistance without any destabilizing effects to the propellant. Potential applications could include less erosive propellants in propellant ammunition for large, medium and small diameter fire arms.

  5. Interfacing microbiology and biotechnology. Conference abstracts

    Energy Technology Data Exchange (ETDEWEB)

    Maupin, Julia A.

    2001-05-19

    The Interfacing Microbiology and Biotechnology Conference was attended by over 100 faculty, post-docs, students, and research scientists from the US, Europe, and Latin America. The conference successfully stimulated communication and the dissemination of knowledge among scientists involved in basic and applied research. The focus of the conference was on microbial physiology and genetics and included sessions on C1 metabolism, archaeal metabolism, proteases and chaperones, gene arrays, and metabolic engineering. The meeting provided the setting for in-depth discussions between scientists who are internationally recognized for their research in these fields. The following objectives were met: (1) The promotion of interaction and future collaborative projects among scientists involved in basic and applied research which incorporates microbial physiology, genetics, and biochemistry; (2) the facilitation of communication of new research findings through seminars, posters, and abstracts; (3 ) the stimulation of enthusiasm and education among participants including graduate and undergraduate students.

  6. Nanoindentation hardness of hot-pressed boron suboxide

    International Nuclear Information System (INIS)

    Machaka, Ronald; Derry, Trevor E.; Sigalas, Iakovos

    2011-01-01

    Highlights: → The load-displacement indentation response of hot-pressed B 6 O is measured and analysed. → The nanoindentation hardness of hot-pressed boron suboxide is reported. → An approach is developed to simulate multi-cycling loading load-displacement curves. → A comprehensive model inter-comparison study of the ISE in hot-pressed B 6 O is also presented. → The fractal dimension is a better measure of ISE than the Meyer's index. - Abstract: The existence of the indentation size effect implies the absence of a single hardness value for the material under investigation especially at low applied loads. In this paper we present an investigation of the indentation size dependence behaviour of nanoindentation hardness in boron suboxide ceramic compacts prepared by uniaxial hot-pressing. Berkovich nanohardness indentations were conducted and analyzed accordingly. In addition to the ordinary Oliver and Pharr method of nanoindentation data analysis, a quantitative approach for the loading curve analysis is proposed. Using the proposed approach, the description and characterization of the observed indentation size effect through the application of the Meyer's law, and the classical and the modified proportional specimen resistance models as well as the multi-fractal scaling law was conducted and is reported. The load-independent hardness values deduced from our quantitative approach are comparable to the results calculated with conventional methods, especially with the multi-fractal scaling law.

  7. Nanoindentation hardness of hot-pressed boron suboxide

    Energy Technology Data Exchange (ETDEWEB)

    Machaka, Ronald, E-mail: Ronald.Machaka@wits.ac.za [DST/NRF Centre of Excellence in Strong Materials, University of the Witwatersrand, P. Bag 3, Wits, Johannesburg (South Africa); School of Chemical and Metallurgical Engineering, University of the Witwatersrand, P.O. Bag 3, Wits, Johannesburg 2050 (South Africa); Derry, Trevor E. [DST/NRF Centre of Excellence in Strong Materials, University of the Witwatersrand, P. Bag 3, Wits, Johannesburg (South Africa); School of Physics, University of the Witwatersrand, P.O. Bag 3, Wits, Johannesburg 2050 (South Africa); Sigalas, Iakovos [DST/NRF Centre of Excellence in Strong Materials, University of the Witwatersrand, P. Bag 3, Wits, Johannesburg (South Africa); School of Chemical and Metallurgical Engineering, University of the Witwatersrand, P.O. Bag 3, Wits, Johannesburg 2050 (South Africa)

    2011-07-15

    Highlights: {yields} The load-displacement indentation response of hot-pressed B{sub 6}O is measured and analysed. {yields} The nanoindentation hardness of hot-pressed boron suboxide is reported. {yields} An approach is developed to simulate multi-cycling loading load-displacement curves. {yields} A comprehensive model inter-comparison study of the ISE in hot-pressed B{sub 6}O is also presented. {yields} The fractal dimension is a better measure of ISE than the Meyer's index. - Abstract: The existence of the indentation size effect implies the absence of a single hardness value for the material under investigation especially at low applied loads. In this paper we present an investigation of the indentation size dependence behaviour of nanoindentation hardness in boron suboxide ceramic compacts prepared by uniaxial hot-pressing. Berkovich nanohardness indentations were conducted and analyzed accordingly. In addition to the ordinary Oliver and Pharr method of nanoindentation data analysis, a quantitative approach for the loading curve analysis is proposed. Using the proposed approach, the description and characterization of the observed indentation size effect through the application of the Meyer's law, and the classical and the modified proportional specimen resistance models as well as the multi-fractal scaling law was conducted and is reported. The load-independent hardness values deduced from our quantitative approach are comparable to the results calculated with conventional methods, especially with the multi-fractal scaling law.

  8. Synthesis of borophenes: Anisotropic, two-dimensional boron polymorphs

    Energy Technology Data Exchange (ETDEWEB)

    Mannix, A. J.; Zhou, X. -F.; Kiraly, B.; Wood, J. D.; Alducin, D.; Myers, B. D.; Liu, X.; Fisher, B. L.; Santiago, U.; Guest, J. R.; Yacaman, M. J.; Ponce, A.; Oganov, A. R.; Hersam, M. C.; Guisinger, N. P.

    2015-12-17

    At the atomic-cluster scale, pure boron is markedly similar to carbon, forming simple planar molecules and cage-like fullerenes. Theoretical studies predict that two-dimensional (2D) boron sheets will adopt an atomic configuration similar to that of boron atomic clusters. We synthesized atomically thin, crystalline 2D boron sheets (i.e., borophene) on silver surfaces under ultrahigh-vacuum conditions. Atomic-scale characterization, supported by theoretical calculations, revealed structures reminiscent of fused boron clusters with multiple scales of anisotropic, out-of-plane buckling. Unlike bulk boron allotropes, borophene shows metallic characteristics that are consistent with predictions of a highly anisotropic, 2D metal.

  9. Development of magnetic resonance technology for noninvasive boron quantification

    International Nuclear Information System (INIS)

    Bradshaw, K.M.

    1990-11-01

    Boron magnetic resonance imaging (MRI) and spectroscopy (MRS) were developed in support of the noninvasive boron quantification task of the Idaho National Engineering Laboratory (INEL) Power Burst Facility/Boron Neutron Capture Therapy (PBF/BNCT) program. The hardware and software described in this report are modifications specific to a GE Signa trademark MRI system, release 3.X and are necessary for boron magnetic resonance operation. The technology developed in this task has been applied to obtaining animal pharmacokinetic data of boron compounds (drug time response) and the in-vivo localization of boron in animal tissue noninvasively. 9 refs., 21 figs

  10. Grounding abstractness: Abstract concepts and the activation of the mouth

    Directory of Open Access Journals (Sweden)

    Anna M Borghi

    2016-10-01

    Full Text Available One key issue for theories of cognition is how abstract concepts, such as freedom, are represented. According to the WAT (Words As social Tools proposal, abstract concepts activate both sensorimotor and linguistic/social information, and their acquisition modality involves the linguistic experience more than the acquisition of concrete concepts. We report an experiment in which participants were presented with abstract and concrete definitions followed by concrete and abstract target-words. When the definition and the word matched, participants were required to press a key, either with the hand or with the mouth. Response times and accuracy were recorded. As predicted, we found that abstract definitions and abstract words yielded slower responses and more errors compared to concrete definitions and concrete words. More crucially, there was an interaction between the target-words and the effector used to respond (hand, mouth. While responses with the mouth were overall slower, the advantage of the hand over the mouth responses was more marked with concrete than with abstract concepts. The results are in keeping with grounded and embodied theories of cognition and support the WAT proposal, according to which abstract concepts evoke linguistic-social information, hence activate the mouth. The mechanisms underlying the mouth activation with abstract concepts (re-enactment of acquisition experience, or re-explanation of the word meaning, possibly through inner talk are discussed. To our knowledge this is the first behavioral study demonstrating with real words that the advantage of the hand over the mouth is more marked with concrete than with abstract concepts, likely because of the activation of linguistic information with abstract concepts.

  11. The effect of boron deficiency on gene expression and boron compartmentalization in sugarbeet

    Science.gov (United States)

    NIP5, BOR1, NIP6, and WRKY6 genes were investigated for their role in boron deficiency in sugar beet, each with a proposed role in boron use in model plant species. All genes showed evidence of polymorphism in fragment size and gene expression in the target genomic DNA and cDNA libraries, with no co...

  12. Research of boron conversion coating in neutron detector with boron deposited GEM

    International Nuclear Information System (INIS)

    Ye Di; Sun Zhijia; Zhou Jianrong; Wang Yanfeng; Yang Guian; Xu Hong; Chen Yuanbai; Xiao Yu; Diao Xungang

    2014-01-01

    GEM is a flourishing new gas detector and nowadays its technology become more mature. It has outstanding properties, such as excellent position resolution, high counting rate, radiation resistance, simple and flexible signal readout, can be large-area detector, wide application range. Detector with boron deposited GEM uses multilayer GEM with deposited boron film as neutron conversion carrier which reads out the information of neutron shot from the readout electrode with gas amplification from every GEM layer. The detector is high performance which can meet the demands of neutron detector of a new generation. Boron deposited neutron conversion electrode with boron deposited cathode and GEM included is the core part of the detector. As boron is a high-melting-point metalloid (> 2 000 ℃), electroplating and thermal evaporation are inappropriate ways. So finding a way to deposit boron on electrode which can meet the demands become a key technology in the development of neutron detector with boron deposited GEM. Compared with evaporation, sputtering has features such as low deposition temperature, high film purity, nice adhesive, thus is appropriate for our research. Magnetron sputtering is a improved way of sputtering which can get lower sputtering air pressure and higher target voltage, so that we can get better films. Through deposit process, the research uses magnetron sputtering to deposit pure boron film on copper electrode and GEM film. This method can get high quality, nice adhere, high purity, controllable uniformity, low cost film with high speed film formation. (authors)

  13. The study of high-boron steel and high-boron cast iron used for shield

    International Nuclear Information System (INIS)

    Pan Xuerong; Lu Jixin; Wen Yaozeng; Wang Zhaishu; Cheng Jiantin; Cheng Wen; Shun Danqi; Yu Jinmu

    1996-12-01

    The smelting, forging, heat-treatment technology and the mechanical properties of three kinds of high-boron steels (type 1: 0.5% boron; type 2: 0.5% boron and 4% or 2% nickel; type 3: 0.5% boron, 0.5% nickel and 0.5% molybdenum) were studied. The test results show that the technology for smelting, forging and heat-treatment (1050 degree C/0.5 h water cooled + 810 degree C/1 h oil cooled) in laboratory is feasible. Being sensitive to notch, the impact toughness of high-boron steel type 1 is not steady and can not meet the technology requirements on mechanical properties. The mechanical properties of both high-boron steel type 2 and type 3 can meet the technological requirements. The smelting technology of high-boron casting iron containing 0.5% boron was researched. The tests show that this casting iron can be smelted in laboratory and its properties can basically satisfy the technology requirements. (10 refs., 6 figs., 11 tab.)

  14. Real-time boronization in PBX-M using erosion of solid boronized targets

    International Nuclear Information System (INIS)

    Kugel, H.W.; Timberlake, J.; Bell, R.; LeBlanc, B.; Okabayashi, M.; Paul, S.; Tighe, W.; Hirooka, Y.

    1994-11-01

    Thirty one real-time boronizations were applied to PBX-M using the plasma erosion of solid target probes. More than 17 g of boron were deposited in PBX-M using this technique. The probes were positioned at the edge plasma to optimize vaporization and minimize spallation. Auger depth profile analysis of poloidal and toroidal deposition sample coupon arrays indicate that boron was transported by the plasma around the torus and deep into the divertors. During discharges with continuous real-time boronization, low-Z and high-Z impurities decreased rapidly as plasma surfaces were covered during the first 20-30 discharges. After boronization, a short-term improvement in plasma conditions persisted prior to significant boron erosion from plasma surfaces, and a longer term, but less significant improvement persisted as boron farther from the edge continued gettering. Real-time solid target boronization has been found to be very effective for accelerating conditioning to new regimes and maintaining high performance plasma conditions

  15. Mechanical Engineering Department technical abstracts

    International Nuclear Information System (INIS)

    Denney, R.M.

    1982-01-01

    The Mechanical Engineering Department publishes listings of technical abstracts twice a year to inform readers of the broad range of technical activities in the Department, and to promote an exchange of ideas. Details of the work covered by an abstract may be obtained by contacting the author(s). Overall information about current activities of each of the Department's seven divisions precedes the technical abstracts

  16. Nuclear code abstracts (1975 edition)

    International Nuclear Information System (INIS)

    Akanuma, Makoto; Hirakawa, Takashi

    1976-02-01

    Nuclear Code Abstracts is compiled in the Nuclear Code Committee to exchange information of the nuclear code developments among members of the committee. Enlarging the collection, the present one includes nuclear code abstracts obtained in 1975 through liaison officers of the organizations in Japan participating in the Nuclear Energy Agency's Computer Program Library at Ispra, Italy. The classification of nuclear codes and the format of code abstracts are the same as those in the library. (auth.)

  17. Little People of America

    Science.gov (United States)

    ... information. World Dwarf Games 2017 Welcome to Little People of America Little People of America (LPA) is a nonprofit organization that provides support and information to people of short stature and their families. LPA is ...

  18. Ceramic silicon-boron-carbon fibers from organic silicon-boron-polymers

    Science.gov (United States)

    Riccitiello, Salvatore R. (Inventor); Hsu, Ming-Ta S. (Inventor); Chen, Timothy S. (Inventor)

    1993-01-01

    Novel high strength ceramic fibers derived from boron, silicon, and carbon organic precursor polymers are discussed. The ceramic fibers are thermally stable up to and beyond 1200 C in air. The method of preparation of the boron-silicon-carbon fibers from a low oxygen content organosilicon boron precursor polymer of the general formula Si(R2)BR(sup 1) includes melt-spinning, crosslinking, and pyrolysis. Specifically, the crosslinked (or cured) precursor organic polymer fibers do not melt or deform during pyrolysis to form the silicon-boron-carbon ceramic fiber. These novel silicon-boron-carbon ceramic fibers are useful in high temperature applications because they retain tensile and other properties up to 1200 C, from 1200 to 1300 C, and in some cases higher than 1300 C.

  19. A quantitative comparison between electrocoagulation and chemical coagulation for boron removal from boron-containing solution

    International Nuclear Information System (INIS)

    Yilmaz, A. Erdem; Boncukcuoglu, Recep; Kocakerim, M. Muhtar

    2007-01-01

    This paper provides a quantitative comparison of electrocoagulation and chemical coagulation approaches based on boron removal. Electrocoagulation process delivers the coagulant in situ as the sacrificial anode corrodes, due to a fixed current density, while the simultaneous evolution of hydrogen at the cathode allows for pollutant removal by flotation. By comparison, conventional chemical coagulation typically adds a salt of the coagulant, with settling providing the primary pollutant removal path. Chemical coagulation was carried out via jar tests using aluminum chloride. Comparison was done with the same amount of coagulant between electrocoagulation and chemical coagulation processes. Boron removal obtained was higher with electrocoagulation process. In addition, it was seen that chemical coagulation has any effect for boron removal from boron-containing solution. At optimum conditions (e.g. pH 8.0 and aluminum dose of 7.45 g/L), boron removal efficiencies for electrocoagulation and chemical coagulation were 94.0% and 24.0%, respectively

  20. A quantitative comparison between electrocoagulation and chemical coagulation for boron removal from boron-containing solution

    Energy Technology Data Exchange (ETDEWEB)

    Yilmaz, A. Erdem [Atatuerk University, Faculty of Engineering, Department of Environmental Engineering, 25240 Erzurum (Turkey)], E-mail: aerdemy@atauni.edu.tr; Boncukcuoglu, Recep [Atatuerk University, Faculty of Engineering, Department of Environmental Engineering, 25240 Erzurum (Turkey); Kocakerim, M. Muhtar [Atatuerk University, Faculty of Engineering, Department of Chemical Engineering, 25240 Erzurum (Turkey)

    2007-10-22

    This paper provides a quantitative comparison of electrocoagulation and chemical coagulation approaches based on boron removal. Electrocoagulation process delivers the coagulant in situ as the sacrificial anode corrodes, due to a fixed current density, while the simultaneous evolution of hydrogen at the cathode allows for pollutant removal by flotation. By comparison, conventional chemical coagulation typically adds a salt of the coagulant, with settling providing the primary pollutant removal path. Chemical coagulation was carried out via jar tests using aluminum chloride. Comparison was done with the same amount of coagulant between electrocoagulation and chemical coagulation processes. Boron removal obtained was higher with electrocoagulation process. In addition, it was seen that chemical coagulation has any effect for boron removal from boron-containing solution. At optimum conditions (e.g. pH 8.0 and aluminum dose of 7.45 g/L), boron removal efficiencies for electrocoagulation and chemical coagulation were 94.0% and 24.0%, respectively.

  1. Biodistribution, toxicity and efficacy of a boronated porphyrin for boron neutron capture therapy

    International Nuclear Information System (INIS)

    Miura, Michiko; Micca, P.; Fairchild, R.; Slatkin, D.; Gabel, D.

    1992-01-01

    Boron-containing porphyrins may be useful for boron neutron capture therapy (BNCT) in the treatment of brain tumors. Porphyrins have been shown to accumulate in tumor tissue and to be essentially excluded from normal brain. However, problems of toxicity may prevent some boron-containing porphyrins from being considered for BNCT. The authors have synthesized the boronated porphyrin 2,4-bis-vinyl-o-nidocarboranyl-deuteroporphyrin IX (VCDP). Preliminary studies in tumor-bearing mice showed considerable uptake of boron at a total dose of 150 μg/gbw with low mortality. They now report that a total dose to mice of ∼ 275 μg VCDP/gbw administered in multiple intraperitoneal (ip) injections can provide 40-50μg B per gram of tumor with acceptable toxicity. Toxicity experiments and a preliminary trial of BNCT in mice given such doses are also reported

  2. Redistribution of boron in leaves reduces boron toxicity.

    Science.gov (United States)

    Reid, Robert J; Fitzpatrick, Kate L

    2009-11-01

    High soil boron (B) concentrations lead to the accumulation of B in leaves, causing the development of necrotic regions in leaf tips and margins, gradually extending back along the leaf. Plants vary considerably in their tolerance to B toxicity, and it was recently discovered that one of the tolerance mechanisms involved extrusion of B from the root. Expression of a gene encoding a root B efflux transporter was shown to be much higher in tolerant cultivars. In our current research we have shown that the same gene is also upregulated in leaves. However, unlike in the root, the increased activity of the B efflux transporter in the leaves cannot reduce the tissue B concentration. Instead, we have shown that in tolerant cultivars, these transporters redistribute B from the intracellular phase where it is toxic, into the apoplast which is much less sensitive to B. These results provide an explanation of why different cultivars with the same leaf B concentrations can show markedly different toxicity symptoms. We have also shown that rain can remove a large proportion of leaf B, leading to significant improvements of growth of both leaves and roots.

  3. The influence of boron dopant on the electrochemical properties of graphene as an electrode material and a support for Pt catalysts

    International Nuclear Information System (INIS)

    Bo, Xiangjie; Li, Mian; Han, Ce; Guo, Liping

    2013-01-01

    Highlights: •More defective sites in graphene after the doping of boron atoms. •Fine dispersion of Pt nanoparticles supported on boron-doped graphene. •Low electron transfer resistance at boron-doped graphene. •High performance of boron-doped graphene as an electrode material or a support for Pt catalysts. -- Abstract: Boron-doped graphene (BGR) is prepared by thermal annealing of graphene oxide (GO) in the presence of boric acid. More defective sites are introduced into GR accompanied by the doping of boron. Low electron transfer resistance towards redox probe is observed at BGR. The BGR modified electrode can effectively distinguish the anodic peaks for ascorbic acid (AA), dopamine (DA), and uric acid (UA). The defective sites of BGR can also act as anchoring sites for the deposition of Pt nanoparticles. When used as a support for Pt electrocatalysts, Pt nanoparticles with an average diameter of 3.2 nm are deposited on BGR. The doping of boron into GR facilitates the dispersion of Pt nanoparticles and increases the utilization efficiency of Pt nanoparticles. The Pt/BGR exhibits significant catalytic activity towards the oxidation of methanol. The results demonstrate that BGR is a good support for Pt catalysts or an electrode material compared with the undoped GR

  4. Boron-containing thioureas for neutron capture therapy

    International Nuclear Information System (INIS)

    Ketz, H.

    1993-01-01

    Melanin is produced in large amounts in malignant melanotic melanomas. Because thiourea compounds are covalently incorporated into melanin during its biosynthesis, the preparation of boronated thiourea-derivatives is of particular interest for the BNCT (Boron Neutron Capture Therapy). Accumulation of boron in tumors by means of boronated thiourea-derivatives may therefore provide levels of 10 B which are useful for BNCT. In BNCT the tumor containing the boron compound is irradiated with epithermal neutrons to generate He- and Li-nuclei from the 10 B which can then destroy the tumor cells. Because of the short ranges of these particles (approximately one cell diameter) the damage will be almost exclusively confined to the tumor leaving normal tissue unharmed. High accumulation of 2-mercapto-1-methylimidazole (methimazole) in melanotic melanomas has been described in the literature. Boronated derivatives of methimazole were therefore synthesized. Boron was in the form of a boronic acid, a nido-carbonate and a mercaptoundeca hydro-closo-dodecaborate (BSH). The synthesis of the boron cluster derivatives of methimazole (nido-carborate- and BSH-derivatives) with 9 resp. 12 boron atoms in the molecule were expected to achieve higher concentrations of boron in the tumor than in the case of the boronic acid compound with its single boron atom. (orig.) [de

  5. ABSTRACT

    African Journals Online (AJOL)

    descriptive statistics, Z-test and multiple regressiion analysis. Results show that the ... protein intake from animal sources, which is less than 10gm/capita /day ... production offish and fish products through effective fisheries extension efforts ...

  6. ABSTRACT

    African Journals Online (AJOL)

    in Imo state, the gender-perceived production constraints; the relative ... to establishing if stereotyping such operations along gender lines will ... difference in returns accruing to male and female small ruminant ..... The bias against Sheep and.

  7. ABSTRACT

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    Commemorating the 100th Anniversary of the Revolution of 1911 Promoting the Deep Development of the CPC History and National History by the Research and Publication of the History of the Revolution of …………1911 Zhu Jiamu (4)

  8. ABSTRACT

    African Journals Online (AJOL)

    Dr Obe

    inner forces (bending moments, shearing forces etc) are usually redistributed. Cracks that often appear within the walls of tall buildings during constructions point to this phenomenon. It has also been recognized that foundation engineering is complicated. (1). Also settlement has been accepted as stress induced and time ...

  9. Abstract

    African Journals Online (AJOL)

    1 Uyole Agr.icultural Research Institute, Ministry of Agriculture, Food Security and Co-operatives,. P.o Box 400 ... from this study suggest that participation in dairy market depended on access to both in-put and output ..... Socio-economics and.

  10. abstract

    Directory of Open Access Journals (Sweden)

    abstract abstract

    2016-07-01

    Full Text Available Introduction: Strawberry (fragaria×ananassa Duch. fruit characterized by short storage life, often estimated last less than one week even under optimum conditions at 8°C. The loss of fruit quality is often caused by gray mold (Botrytis cinerea that is the most frequent reported postharvest disease in strawberry during storage (6. In recent years, considerable attention has given to elimination of synthetic chemical and fungicides application and development of various alternative strategies for controlling fruit and vegetables diseases (2. One strategy is replacement of natural products with plant origin such as essential oil and methyl salicylate (MeSA. Essential oils are volatile, natural and complex compounds characterized by a strong odor formed by aromatic plants in form of secondary metabolites. In nature, essential similar oils that extract from lavender (Lavandula angustifolia play an important role in protection of the plants against pathogen incidence that can be replaced by synthetic fungicides (1, 4 and 14. MeSA is also a volatile natural compound synthesized from salicylic acid which has an important role in the plant defense-mechanism, as well as plant growth and development (5, 19 and 20. Therefore, the main objective of this research was to study the effects of MeSA and lavender essential oil (LEO on decay control caused by Botrytis cinerea as well as post-harvest quality indices of strawberry fruits during cold storage. Material and Methods: First, antifungal activity was studied by using a contact assay (in vitro, which produces hyphal growth inhibition. Briefly, potato dextrose agar (PDA plates were prepared using 8 cm diameter glass petri dishes and inhibitory percentage was determined. For in-vivo assessment of LEO and MeSA effects on Botrytis-caused fungal disease control, the experiment was conducted as factorial in completely randomized design (CRD with 3 replicates. The treatments were 3 concentration of LEO including 0, 500 and 1000 µl L-1 and 3 level of MeSA including 0, 0.1 and 0.2 mM. After treatment, the fruits were inoculated by Botrytis suspension and transferred to storage and quality parameters were evaluated after 7, 14 and 21 days. At each sampling time, disease incidence, weight loss, titratable acidity, pH, soluble solids content, vitamin C and antioxidant activity were measured. Results and Discussion: The results showed that both LEO and MeSA treatments had significant effects on inhibition of mycelium growth within in-vitro condition (p < 0.05. Inhibition rate of mycelium growth significantly improved by LEO and MeSA concentration increase of, (Table 1. At in-vivo assessment, diseases incidence of treated fruits with 500 µl L-1 LEO and 0.1 mM MeSA were 32% and 64% lower than untreated fruits, respectively (Fig. 1 and 2. During storage period, the percentage of infected fruits increased. In addition, LEO and MeSA treatments affected quality parameters of strawberry fruits including titratable acidity, soluble solids content, vitamin C and antioxidant activity. Treated fruits had a high content of soluble solids, vitamin C and antioxidant activity in comparison to untreated fruits (Table 3 and 4. Probably ascorbic acid decreased through fungal infection duo to cell wall break down during storage. Any factors such as essential oil and salicylate that inhibit fungal growth can help preserving vitamin C in stored products. High level of vitamin C and antioxidant activity was observed in treated fruits with 0.1 mM MeSA and 500 µl L-1 LEO. In controlling weight loss of fruits, 0.2 mM of MeSA and 500 µl L-1 of LEO had significant effects, although MeSA was more effective than LEO treatments, possibly due to elimination of respiration rates and fungi infection (Table 4. Therefore, LEO and MeSA with fungicide effects could be replaced with synthetic fungicides in controlling fungal diseases of strawberry and maintain fruits quality during storage. Conclusion: In conclusion, our results showed that LEO and MeSA treatments could be safe and used to prevent infection of strawberry during storage, although LEO was more effective than MeSA treatments. Concentration of 500 μl L-1 of LEO and 0.1 mM MeSA could control fungal infection of fruits during storage. Also, LEO and MeSA treatments can extend shelf life for over the minimum period required to transit strawberries to foreign markets and without affecting quality, adversely. However, future studies are necessary to fully understand the mechanisms by which LEO and MeSA treatments may act as a fungicide and increase their postharvest life.

  11. Abstract

    African Journals Online (AJOL)

    a route of HIV transmission with sex (p=0.003) and age (p=0.000) being highly ... preventing HIV, prevention of mother-to-child transmission of HIV (PMTCT), health behaviour and ..... order to determine which infant feeding methods were perceived ..... breast diseases, cancer, insufficient milk, work and pregnancy.

  12. Abstract

    African Journals Online (AJOL)

    ATTAMAH C. O

    female ̅=3.50; difference in mean{dm} = -0.70). Male entrepreneurs ... with the variance more on lack of information facilities (male ̅= 2.28; female. ̅= 2.60; dm = -0.32). ..... Issa R. (2009). Climate Change and Livestock Production Frontier.

  13. Abstract ~. ,

    African Journals Online (AJOL)

    and Marketed in'Morogoro Municipality,"Taniania. lR. ... It was concluded that water adulteration ofmilk in ... Despite the fact that infofmal milk marketing i{ ..... Least sqoares ~einsand standard error of means (SEM) for'milk quality variables;.

  14. ABSTRACT

    African Journals Online (AJOL)

    Objective: To determine the incidence of post operative SSI after primary total hip arthroplasty. Design: A retrospective cohort study. ... Conclusion: The risk of post operative SSI after total hip arthroplasties is low in the African setting. Further investigation is .... knee replacements for osteoarthritis. J. Bone Joint. Surg.

  15. Abstract

    Indian Academy of Sciences (India)

    2017-03-10

    Mar 10, 2017 ... factors with low to moderate effect which have been described (Klareskog et al. 2006). The strongest ... 2014). Several studies in GWAS and meta-analyses ... All patients and healthy controls gave informed consent to .... HLA-DQB1 encoded chain of MHC-II protein and HLA-DQA2 encoded chain of MHC-II ...

  16. Abstract

    African Journals Online (AJOL)

    Maru Shete

    business owned and controlled equally by the members that is targeted to break the ... The Poverty Reduction Strategy Programme of OSHO is focused in supporting the ..... The Report of United Nations (2005) indicates an improvement in the.

  17. Abstract

    African Journals Online (AJOL)

    PROF. O. E. OSUAGWU

    An Authoring system is a software with pre-programmed elements which allows both programmers ... doing things in all aspects of human endeavour. ... learning is offered through an Internet .... based or problem-based learning environment.

  18. abstract

    African Journals Online (AJOL)

    status of households in Owemi agricultural area of Imo state, isolate the determinants of ... importation, the country has hardly ever provided enough food for her teeming ..... Third in importance is the sale of valuable items as a coping strategy. The type ... while 70% preferred begging for food to dying of starvation. However,.

  19. Abstracts

    International Nuclear Information System (INIS)

    1989-09-01

    The proceedings contain 106 papers of which 2 fall under the INIS Scope. One concerns seismic risk assessment at radioactive waste repositories in the U.S., the other concerns the possibility of predicting earthquakes from changes in radon 222 levels in selected ground water springs of northern Italy. (M.D.)

  20. Abstract

    African Journals Online (AJOL)

    dell

    The study was conducted on high schools around the vicinity of Jimma. University easy to ... and community/Kebele leaders were sources of information and media ... biological, health sciences, social sciences ...... and one or more elementary.

  1. Abstract

    African Journals Online (AJOL)

    `123456789jkl''''#

    1, 2Department of Educational Technology Obafemi Awolowo University, Ile-Ife, Nigeria oasofowora@yahoo.com. 46 ... Geography teachers drawn from secondary schools in Osun State. ..... Elementary/Secondary Education Handbook an.

  2. Abstract

    African Journals Online (AJOL)

    `123456789jkl''''#

    extent of the integration of the new technology in teaching and learning Geography in Nigerian ... mounted pressure advocating for the removal ... which reduce opportunities for developing .... the fact the subject has distance itself from the.

  3. abstract

    Directory of Open Access Journals (Sweden)

    . user

    2016-02-01

    Full Text Available Introduction: One of the microbiological preparations used for this study was Effective Microorganisms (EM, being a commercial mixture of photosynthesizing bacteria, Actinomycetes, lactic acid bacteria, yeasts and fermenting fungi. The microbiological composition of the EM concentrateincludesStreptomyces albus, Propioni bacterium freudenreichil, Streptococcus lactis, Aspergillus oryzae, Mucor hiemalis, Saccharomycescerevisiae and Candida utilis. Moreover, EM also contains an unspecified amount of Lactobacillus sp. Rhodo pseudomonas sp. and Streptomyces griseus. Effective Microorganisms have a positive effect on the decomposition of organic matter, limiting putrefaction, increasing nitrogen content in the root medium of plants, phosphorus, improving soil fertility and as a result contributing to the growth and development of the root systems of plants. Selection of almond vegetative rootstocks for water stress tolerance is important for almond crop production in arid and semi-arid regions. The study of the eco-morphological characteristics that determine the success of a rootstock in a particular environment is a powerful tool for both agricultural management and breeding purposes. The aim of this work was to select the new rootstocks for water shortage tolerance, impact of water stress as well as Effective Microorganism (EM on morphological characteristics of almond rootstocks. Materials and Methods: In order to select the new rootstocks for water shortage tolerance, impact of water stress as well as EMonmorphologicalcharacteristics of almondrootstocks were studiedin thedepartment ofHorticulture, Ferdowsi University of Mashhad, in 2011-2012. The experiment was carried out with four replications in a completely random blockdesign to study the effects of two concentrations of EM (0 and 1%, three irrigation levels (normal irrigation 100%-control-and irrigation after depletion of 33 and 66% of available water, and four almond rootstocks including GF677 and selected natural hybrid of peach × almond (H1and H2, and almond vegetative rootstock (local control.In this study,EMtreatments for 60 days before stress treatments were applied so that in each irrigation, EM solution to a concentration of one percent was given to half of the experiment pots. Other pots were irrigated equally with normal water. Stress levels were applied from July as follow: full irrigation, watering after unloading 33% and 66% soil moisture availability. In order to evaluate the performance, seedling survival, plant growth, number of leaves, leaf area, root fresh and dry weight and leaves and root length were measured. Results and Discussion: Analysis of variance showed that between rootstock levels across all treatments were significantly differences at 0.01 level of probability. Comparison of means showed that the highest fresh and dry weight and leaf are awere observed forGF677and H1.Rootstockannualgrowth rate was also different. Most of the growth was related to the H1 Rootstocks. Thes urvival ratewas significantly different from the Rootstocks ofGF677,andH1showedthe highestpercentage of survival. The degree of adaptation to drought in varieties of almonds is different. The results showed that changes ingrowthparametersinGF677and H1were observed less often than other rootstocks. Because of strong roots,GF677and H1continue to attract more minerals under stress conditions. Analysis of variance showed that the between irrigation levels for all treatments were significantly different at 0.01 level of probability. Comparison of means showed that among the study traits, the highest amount was obtained from complete irrigation, while irrigationat66 percenthad the least amount. Water stress may directly affect photosyn thesis, through leaf photochemicalprocessorindirectly,byclosing stomata, reducingleaf area and growth. The results showed that the levels of(EM on the leaf surface, leaf number, annual growth, root dry weight and volume were significantly different (p

  4. Abstract

    African Journals Online (AJOL)

    UDS-CAPTURED

    examines the extent of women farmers' access to credit from Rural Banks (RBs) in the Upper East. Region of Ghana. .... In this regard, anybody who does not attempt to get credit from formal, semi-formal/endogenous or ... District and the Builsa Community Rural Bank with its headquarters at Sandema in the Builsa. District.

  5. Abstract

    African Journals Online (AJOL)

    ­E¢b

    development of its economy presupposes entrepreneurial direction, which is ... and independence. Ethiopian business men and women should take intelligent risks ... opportunities. Such a strategy helps Ethiopian entrepreneurship to grow. .... propensity, and high energy decreased as the cultural distance from the United ...

  6. Abstract

    Indian Academy of Sciences (India)

    2017-03-10

    Mar 10, 2017 ... autoimmune and infectious diseases including type 1 diabetes (Nakanishi and Inoko 2006) and chronic HCV infection (Tibbs et al. 1996). Additionally, it was suggested that it may be a shared epitope for RA (Li et al. 2013). According to these data and our findings, we can suggest that there is an interaction ...

  7. Abstract

    Directory of Open Access Journals (Sweden)

    Maria Jose Carvalho de Souza Domingues

    2003-01-01

    Full Text Available The practice of teaching, in actuality, shows the necessity of teachers and students coming together to form a behavior that is different from the traditional model of teaching. The unity formed from various types of knowledge and the relation between theory and practice show themselves to be fundamental. Starting in 2002, and in search of this unity, a project that hoped to unify the disciplines taught in the second semester of the course in Administration was implemented. During the semester, a single work sought to relate the theories studied with the reality of an organization. Each professor evaluated the works from the point of view of his discipline, as well as the presentation, in general, of the group. It can be affirmed that seeking to bring together various types of knowledge necessarily passes to a rethinking of the postures of teachers and students.

  8. ABSTRACTS

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    4The Current Trends in Global Mineral Exploration and Development LIU Shucken (Information Center of Ministry of Land and Resources, Beijing 100812, China) Abstract: This paper introduces the main issues that the global mineral exploration and development are faced with. The main issues of focus include: the mineral exploration has rapidly recovered from the short depression caused by the effects of global financial crisis; most of the important mineral reserves have continued to grow; there has been continued rapid growth in mining development investment; the supply capacity of mineral products has increased; mergers and acquisitions of mining company are stirring, and multinational mergers & acquisitions has become mainstream,

  9. Abstract

    African Journals Online (AJOL)

    used standardised scales to measure the level of HIV stigma over time. A repeated .... with studies that focused so heavily 'on the beliefs and attitudes of those who are .... to harm the PLHA (e.g. ridicule, insults, blame), 8 items, alpha. = 0.886; (ii) ... self based on HIV status, 5 items, alpha = 0.906; (iii) health care neglect – in ...

  10. Abstract

    African Journals Online (AJOL)

    Getachew

    realistic distribution of no-show data in modeling the cost function was considered using data collected from the .... the paper models the cost function based on a realistic probability distributions based on the historical data is a .... Plot of Revenue generated vs. overbooking for two class case (at $500. Compensation Cost ...

  11. ABSTRACT

    Directory of Open Access Journals (Sweden)

    Michelle de Stefano Sabino

    2011-12-01

    Full Text Available This paper aims to describe and to analyze the integration observed in the Sintonia project with respect to the comparison of project management processes to the model of the Stage-Gate ®. The literature addresses these issues conceptually, but lack an alignment between them that is evident in practice. As a method was used single case study. The report is as if the Sintonia project, developed by PRODESP - Data Processing Company of São Paulo. The results show the integration of project management processes with the Stage-Gate model developed during the project life cycle. The formalization of the project was defined in stages in which allowed the exploitation of economies of repetition and recombination to the development of new projects. This study contributes to the technical vision in dealing with the integration of project management processes. It was concluded that this system represents an attractive way, in terms of creating economic value and technological innovation for the organization.

  12. Abstracts

    International Nuclear Information System (INIS)

    2001-01-01

    The minutes of the Latinamerican Geology Meeting and the 3. Uruguayan Meeting organized by the National Direction of Mining and Geology (DINAMIGE) and Uruguayan Geology Society (Uruguay) includes topics such as: paleontology, sedimentation, stratigraphy, fossils, paleoclimatology, geo tectonics, coal deposits, minerals res sources, tectonic evolution of the Andes Mountain Ranges, IGCP Project, Environmental geology, Hydrogeology, fuels, and geomorphology

  13. Abstracts

    International Nuclear Information System (INIS)

    2013-01-01

    The power point presentation is about: danger identification, caracterization, evaluation exposition, risk (CAC, 1997; FAO, 2007), European food safety authority, foodrisk organization, pathogens risk ranking, risk reduction, gubernamental responsability

  14. ABSTRACT

    Indian Academy of Sciences (India)

    Efforts have also been successfully made to include the study of rock art in the school/ college curriculum so as to help develop awareness amongst the students and general public about the need to preserve this cultural heritage for the posterity and also to highlight its importance in tourism industry. rock art and their ...

  15. ABSTRACT

    African Journals Online (AJOL)

    BSN

    A CHEMICAL STlJDY OF AN I 'DI GENO KNOWLED<:E SYSTEM OF ... preservation of "kindirmo" with water and ethanol extracts of seeds and husk of. CO\\\\'J)Ca for ... Such facilities arc ho1\\·ever not a\\ailable to most peasant animal farmers.

  16. Abstract

    African Journals Online (AJOL)

    PROF. OLIVER OSUAGWA

    Many mathematical models of stochastic dynamical systems were based on the assumption that the drift ... stochastic process with state space S is a ..... The algorithm was implemented through a MatLab script and the result of the simulation is.

  17. ABSTRACTS

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    Wu Jie and Duan Yanchao. The current line drawing of Laterolog and its application. PI, 2011, 25(4) : 1 - 4 The current line plays an important role in the directly understanding the characteristics of Laterolog tool. A method of drawing current lines for the discrete potential data based on the Finite Element calculation is studied. It solves a series of key problems, including the selection of step length, the identification of direction, treatment of nmtation point and the control of stop. A drawing program is written by MATLAB software. Taking the current line drawing of the dual Laterolog logging as an example, we analyze the tool's investigation characteristics in the several formations such as homogeneous, low or high invasion, and invasion with shoulder. These results verify the effectiveness of the new method. The method can be applied to the other kinds of Laterolog tools to draw their current lines and analyze their investigation characteristics.

  18. Abstract

    African Journals Online (AJOL)

    on human development are sufficiently important to warrant an integration of. HIV and .... interaction of HIV and malaria22, The discussions that follow further sub- .... HIV —MTCT and the paediatric management of children born of ser0p0$l-.

  19. Abstract

    DEFF Research Database (Denmark)

    Tafdrup, Oliver

    2013-01-01

    Udgivet som en del af Tidskrifts specialudgivelse om Adorno. http://tidskrift.dk/data/50/Aforismesamling.pdf......Udgivet som en del af Tidskrifts specialudgivelse om Adorno. http://tidskrift.dk/data/50/Aforismesamling.pdf...

  20. Photodegradation of aniline by goethite doped with boron under ultraviolet and visible light irradiation

    International Nuclear Information System (INIS)

    Liu, Guanglong; Liao, Shuijiao; Zhu, Duanwei; Liu, Linghua; Cheng, Dongsheng; Zhou, Huaidong

    2011-01-01

    Highlights: → Goethite modified by boron was prepared by sol-gel method in presence of boron acid at the low temperature. → B-goethite has slight red shift in the band gap transition beside their stronger light absorption compared with pristine goethite. → The results showed that semiconductor photocatalytic reaction mechanism should exist in the process of aniline degradation with goethite and B-goethite as photocatalyst. -- Abstract: In the present study, goethite and goethite doped with boron (B-goethite) were employed to detect the presence or absence of semiconductor photocatalytic reaction mechanism in the reaction systems. B-goethite was prepared by sol-gel method in presence of boron acid in order to improve its photocatalystic efficiency under the ultraviolet and visible light irradiation. The optical properties of goethite and B-goethite were characterized by ultraviolet and visible absorption spectra and the result indicated that B-goethite has slight red shift in the band gap transition beside their stronger light absorption compared with pristine goethite. Degradation of aniline was investigated in presence of goethite and B-goethite in aqueous solution. It was found that the B-goethite photocatalyst exhibited enhanced ultraviolet and visible light photocatalytic activity in degradation of aniline compared with the pristine goethite. The photocatalytic degradation mechanism of B-goethite was discussed.

  1. Togetherness in the Americas.

    Science.gov (United States)

    Black, Jan Knippers

    1984-01-01

    There is a growing unacknowledged reality to the oneness of America. Latin America is increasingly sharing not only the blessings of U.S.-style modernization, but its demons as well. Also, many problems that have long plagued Latin America, e.g., indebtedness and militarism, are becoming more apparent in the United States. (RM)

  2. Abstract concepts in grounded cognition

    NARCIS (Netherlands)

    Lakens, D.

    2010-01-01

    When people think about highly abstract concepts, they draw upon concrete experiences to structure their thoughts. For example, black knights in fairytales are evil, and knights in shining armor are good. The sensory experiences black and white are used to represent the abstract concepts of good and

  3. Modal abstractions of concurrent behavior

    DEFF Research Database (Denmark)

    Nielson, Flemming; Nanz, Sebastian; Nielson, Hanne Riis

    2011-01-01

    We present an effective algorithm for the automatic construction of finite modal transition systems as abstractions of potentially infinite concurrent processes. Modal transition systems are recognized as valuable abstractions for model checking because they allow for the validation as well...... as refutation of safety and liveness properties. However, the algorithmic construction of finite abstractions from potentially infinite concurrent processes is a missing link that prevents their more widespread usage for model checking of concurrent systems. Our algorithm is a worklist algorithm using concepts...... from abstract interpretation and operating upon mappings from sets to intervals in order to express simultaneous over- and underapprox-imations of the multisets of process actions available in a particular state. We obtain a finite abstraction that is 3-valued in both states and transitions...

  4. Technical abstracts: Mechanical engineering, 1990

    International Nuclear Information System (INIS)

    Broesius, J.Y.

    1991-01-01

    This document is a compilation of the published, unclassified abstracts produced by mechanical engineers at Lawrence Livermore National Laboratory (LLNL) during the calendar year 1990. Many abstracts summarize work completed and published in report form. These are UCRL-JC series documents, which include the full text of articles to be published in journals and of papers to be presented at meetings, and UCID reports, which are informal documents. Not all UCIDs contain abstracts: short summaries were generated when abstracts were not included. Technical Abstracts also provides descriptions of those documents assigned to the UCRL-MI (miscellaneous) category. These are generally viewgraphs or photographs presented at meetings. An author index is provided at the back of this volume for cross referencing

  5. Metaphor: Bridging embodiment to abstraction.

    Science.gov (United States)

    Jamrozik, Anja; McQuire, Marguerite; Cardillo, Eileen R; Chatterjee, Anjan

    2016-08-01

    Embodied cognition accounts posit that concepts are grounded in our sensory and motor systems. An important challenge for these accounts is explaining how abstract concepts, which do not directly call upon sensory or motor information, can be informed by experience. We propose that metaphor is one important vehicle guiding the development and use of abstract concepts. Metaphors allow us to draw on concrete, familiar domains to acquire and reason about abstract concepts. Additionally, repeated metaphoric use drawing on particular aspects of concrete experience can result in the development of new abstract representations. These abstractions, which are derived from embodied experience but lack much of the sensorimotor information associated with it, can then be flexibly applied to understand new situations.

  6. Boron removal in radioactive liquid waste by forward osmosis membrane

    Energy Technology Data Exchange (ETDEWEB)

    Doo Seong Hwang; Hei Min Choi; Kune Woo Lee; Jei Kwon Moon [KAERI, Daejeon (Korea, Republic of)

    2013-07-01

    This study investigated the treatment of boric acid contained in liquid radioactive waste using a forward osmosis membrane. The boron permeation through the membrane depends on the type of membrane, membrane orientation, pH of the feed solution, salt and boron concentration in the feed solution, and osmotic pressure of the draw solution. The boron flux begins to decline from pH 7 and increases with an increase of the osmotic driving force. The boron flux decreases slightly with the salt concentration, but is not heavily influenced by a low salt concentration. The boron flux increases linearly with the concentration of boron. No element except for boron was permeated through the FO membrane in the multi-component system. The maximum boron flux is obtained in an active layer facing a draw solution orientation of the CTA-ES membrane under conditions of less than pH 7 and high osmotic pressure. (authors)

  7. 15th International Conference on Boron Chemistry (IMEBORON XV)

    Czech Academy of Sciences Publication Activity Database

    Grüner, Bohumír; Štíbr, Bohumil

    2015-01-01

    Roč. 87, č. 2 (2015), s. 121 ISSN 0033-4545 Institutional support: RVO:61388980 Keywords : boranes * boron * boron materials * carboranes * IMEBORON XV * medicinal chemistry Subject RIV: CA - Inorganic Chemistry

  8. Structure prediction of boron-doped graphene by machine learning

    Science.gov (United States)

    M. Dieb, Thaer; Hou, Zhufeng; Tsuda, Koji

    2018-06-01

    Heteroatom doping has endowed graphene with manifold aspects of material properties and boosted its applications. The atomic structure determination of doped graphene is vital to understand its material properties. Motivated by the recently synthesized boron-doped graphene with relatively high concentration, here we employ machine learning methods to search the most stable structures of doped boron atoms in graphene, in conjunction with the atomistic simulations. From the determined stable structures, we find that in the free-standing pristine graphene, the doped boron atoms energetically prefer to substitute for the carbon atoms at different sublattice sites and that the para configuration of boron-boron pair is dominant in the cases of high boron concentrations. The boron doping can increase the work function of graphene by 0.7 eV for a boron content higher than 3.1%.

  9. Boron: out of the sky and onto the ground

    International Nuclear Information System (INIS)

    Kuehl, D.K.

    1975-01-01

    Now an accepted, engineered material for aerospace applications, boron is taking its place on the ground. Both current production applications, prototype (development) applications, and speculative applications abound. In the leisure product market, boron epoxy or boron aluminum has been used or tried in golf clubs (in combination with graphite epoxy or to reinforce aluminum or steel), in tennis racquets, in bicycles, racing shells, skis and skipoles, bows and arrows, and others. In the industrial area, boron has been used to reduce fatigue, increase stiffness, or for its abrasive properties. Textile machinery, honing tools, and cut off wheels or saws are among the applications. In the medical field, prosthetics and orthotic braces, wheel chairs, canes, and crutches are all good applications for boron. Applications for boron in transportation, construction, and heavy industry are also possible. The volume of boron used in these applications could have a major impact on prices, making boron composite parts cost competitive with conventional materials. (U.S.)

  10. The Influence of Parameters Affecting Boron Removal by Electrocoagulation Process

    KAUST Repository

    Zeboudji, B.; Drouiche, Nadjib; Lounici, Hakim; Mameri, Nabil; Ghaffour, NorEddine

    2013-01-01

    , this process requires chemical addition and important additional investment, operation and maintenance, and energy costs. Electrocoagulation (EC) process can be used to achieve such low boron concentration. In this work, the removal of boron from aqueous

  11. Boron Removal in Seawater Reverse Osmosis System

    KAUST Repository

    Rahmawati, Karina

    2011-07-01

    Reverse osmosis successfully proves to remove more than 99% of solute in seawater, providing fresh water supply with satisfied quality. Due to some operational constraints, however, some trace contaminants removal, such as boron, cannot be achieved in one pass system. The stringent criterion for boron from World Health Organization (WHO) and Saudi Arabia local standard (0.5 mg/l) is hardly fulfilled by single pass sea water reverse osmosis (SWRO) plants. Some design processes have been proposed to deal with boron removal, but they are not economically efficient due to high energy and chemical consumption. The objective of this study was to study boron removal by different reverse osmosis membranes in two pH conditions, with and without antiscalant addition. Thus, it was expected to observe the possibility of operating single pass system and necessity to operate two pass system using low energy membrane. Five membrane samples were obtained from two different manufacturers. Three types of feed water pH were used, pH 8, pH 10, and pH 10 with antiscalant addition. Experiment was conducted in parallel to compare membrane performance from two manufacturers. Filtration was run with fully recycle mode for three days. Sample of permeate and feed were taken every 12 hours, and analyzed for their boron and TDS concentration. Membrane samples were also tested for their surface charge. The results showed that boron rejection increases as the feed pH increases. This was caused by dissociation of boric acid to negatively charged borate ion and more negatively charged membrane surface at elevated pH which enhance boron rejection. This study found that single pass reverse osmosis system, with and without elevating the pH, may not be possible to be applied because of two reasons. First, permeate quality in term of boron, does not fulfill WHO and local Saudi Arabia regulations. Second, severe scaling occurs due to operation in alkaline condition, since Ca and Mg concentration are

  12. Boron tolerance in NS wheat lines

    Directory of Open Access Journals (Sweden)

    Brdar Milka

    2006-01-01

    Full Text Available Boron is an essential micronutrient for higher plants. Present in excessive amounts boron becomes toxic and can limit plant growth and yield. Suppression of root growth is one of the symptoms of boron toxicity in wheat. This study was undertaken to investigate the response of 10 perspective NS lines of wheat to high concentrations of boron. Analysis of root growth was done on young plants, germinated and grown in the presence of different concentrations of boric acid (0, 50,100 and 150 mg/1. Significant differences occurred between analyzed genotypes and treatments regarding root length. Average suppression of root growth was between 11,6 and 34,2%, for line NS 252/02 are even noted 61,4% longer roots at treatments in relation to the control. Lines with mean suppression of root growth less than 20% (NS 101/02, NS 138/01, NS 53/03 and NS 73/02 may be considered as boron tolerant. Spearmans coefficients showed high level of agreement regarding rang of root length for genotypes treated with 100 and 150 mg H3BO3/l.

  13. Hot ductility behavior of boron microalloyed steels

    International Nuclear Information System (INIS)

    Lopez-Chipres, E.; Mejia, I.; Maldonado, C.; Bedolla-Jacuinde, A.; Cabrera, J.M.

    2007-01-01

    The current study analyses the influence of boron contents (between 29 and 105 ppm) on the hot ductility of boron microalloyed steels. For this purpose, hot tensile tests were carried out at different temperatures (700, 800, 900 and 1000 deg. C) at a constant true strain rate of 0.001 s -1 . In general, results revealed an improvement of the hot ductility of steels at increasing boron content. At 700, 900 and 1000 deg. C the ductility is higher than at 800 deg. C, where boron microalloyed steels exhibit a region of ductility loss (trough region). Likewise, dynamic recrystallization only occurred at 900 and 1000 deg. C. The fracture surfaces of the tested steels at temperatures giving the high temperature ductility regime show that the fracture mode is a result of ductile failure, whereas it is ductile-brittle failure in the trough region. Results are discussed in terms of dynamic recrystallization and boron segregation towards austenite grain boundaries, which may retard the formation of pro-eutectoid ferrite and increase grain boundary cohesion

  14. Technology of boron-containing polyphosphate fertilizer 'Phosphobor'

    International Nuclear Information System (INIS)

    Aldabergenov, M.K.; Balakaeva, T.G.

    1995-01-01

    A technology is developed for producing 'Phosphobor' fertilizer based on the rock phosphate weal (17-18% P 2 O 5 ) with additions of boron-magnesium compound. Boron is part of polyphosphate fertilizer in the form of polymeric compounds of phosphorus and boron. Phosphorus and boron copolymers -boratophosphates - are easily formed in the process of polyphosphate fertilizers production, since borates undergo a mutual polycondensation reaction with phosphates. 8 refs., 1 fig

  15. Determination of free carbon content in boron carbide ceramic powders

    International Nuclear Information System (INIS)

    Castro, A.R.M. de; Lima, N.B. de; Paschoal, J.O.A.

    1990-01-01

    Boron carbide is a ceramic material of technological importance due to its hardness and high chemical and thermal stabilities. Free carbon is always found as a process dependent impurity in boron carbide. The development of procedures for its detection is required because its presence leads to a degradation of the boron carbide properties. In this work, several procedures for determining free carbon content in boron carbide specimens are reported and discussed for comparison purposes. (author) [pt

  16. Hyperbranched-polyol-tethered poly (amic acid) electrospun nanofiber membrane with ultrahigh adsorption capacity for boron removal

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Zhe; Wu, Zhongyu; Zhang, Yufeng; Meng, Jianqiang, E-mail: jianqiang.meng@hotmail.com

    2017-04-30

    Highlights: • Electrospun nanofiber membranes were grafted with hyperbranched polyols. • The membrane had a maximum boron uptake of 5.68 mmol/g. • The membrane could adsorb 0.82 mmol/g boron from a 5 mg/L solution in 15 min. • The membrane obeyed the Langmuir and the pseudo-first-order kinetic model. • The regeneration efficiency remained over 90% after 10 cycled uses. - Abstract: The development of efficient adsorbents with high sorption capacity remains as a challenge for the removal of micropollutants occurred globally in water resources. In this work, poly (amic acid) (PAA) electrospun nanofiber membranes grafted with hyperbranched polyols were synthesized and used for boron removal. The PAA nanofiber was reacted with hyperbranched polyethylenimine (HPEI) and further with glycidol to introduce the vicinal hydroxyl groups. The chemical composition and surface characteristics of the obtained PAA-g-PG membranes were evaluated by FESEM, FTIR, XPS and water contact angles (WCA) measurements. The boron adsorption thermodynamics and kinetics were investigated systematically. The results showed that the PAA nanofiber spun from concentration of 15% had uniform morphology and narrow diameter distribution. The PAA-g-PG nanofiber membrane had a maximum boron uptake of 5.68 mmol/g and could adsorb 0.82 mmol/g boron from a 5 mg/L solution in 15 min. Both the high surface area of nanofibers and the hyperbranched structure should contribute to the high boron uptake and high adsorption rate. The nanofiber membrane obeyed the Langmuir adsorption model and the pseudo-first-order kinetic model. The regeneration efficiency of the nanofiber membrane remained 93.9% after 10 cycled uses, indicating good regenerability of the membrane.

  17. Evaluating the complexation behavior and regeneration of boron selective glucaminium-based ionic liquids when used as extraction solvents

    International Nuclear Information System (INIS)

    Joshi, Manishkumar D.; Steyer, Daniel J.; Anderson, Jared L.

    2012-01-01

    Highlights: ► Glucaminium-based ILs exhibit high selectivity for boron species using DLLME. ► The concentration of glucaminium-based IL affects type of boron complex formed. ► Use of 0.1 M HCl allows for regeneration of the IL solvent following extraction. ► Selectivity of the glucaminium-based ILs for boron species in seawater is similar to Milli-Q water. - Abstract: Glucaminium-based ionic liquids are a new class of solvents capable of extracting boron-species from water with high efficiency. The complexation behavior of these ILs with borate was thoroughly studied using 11 B NMR. Two different complexes, namely, monochelate complex and bischelate complex, were observed. 11 B NMR was used extensively to determine the formation constants for monochelate and bischelate complexes. The IL concentration was observed to have a significant effect on the IL–borate complexes. Using an in situ dispersive liquid–liquid microextraction (in situ DLLME) method, the extraction efficiency for boron species was increased dramatically when lithium bis[(trifluoromethyl)sulfonyl]imide (LiNTf 2 ) was used as the metathesis salt in an aqueous solution containing 0.1 M sodium chloride. IL regeneration after extraction was achieved using 0.1 M hydrochloric acid. The extraction efficiency of boron species was consistent when the IL was employed after three regeneration cycles. The selectivity of the IL for boron species in synthetic seawater samples was similar to performing the same extraction from Milli-Q water samples.

  18. Screening of Wheat Genotypes for Boron Efficiency in Bangladesh

    Science.gov (United States)

    A number of Bangladeshi wheat genotypes (varieties and advanced lines) have been tested for boron efficiency through sand culture experiments over two years (2007-08 & 2008-09) against two Thai check varieties ‘Fang 60’ (boron efficient) and ‘SW41’ (boron inefficient). Performances of the genotypes ...

  19. The effects of boron management on soil microbial population and ...

    African Journals Online (AJOL)

    Soil microorganisms directly influence boron content of soil as maximum boron release corresponds with the highest microbial activity. The objective of this study is to determine the effects of different levels of boron fertilizer on microbial population, microbial respiration and soil enzyme activities in different soil depths in ...

  20. Abstract Interpretation and Attribute Gramars

    DEFF Research Database (Denmark)

    Rosendahl, Mads

    The objective of this thesis is to explore the connections between abstract interpretation and attribute grammars as frameworks in program analysis. Abstract interpretation is a semantics-based program analysis method. A large class of data flow analysis problems can be expressed as non-standard ...... is presented in the thesis. Methods from abstract interpretation can also be used in correctness proofs of attribute grammars. This proof technique introduces a new class of attribute grammars based on domain theory. This method is illustrated with examples....

  1. Synthesis of nano-sized amorphous boron powders through active dilution self-propagating high-temperature synthesis method

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Jilin [The State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070 (China); Gu, Yunle [School of Material Science and Engineering, Wuhan Institute of Technology, Wuhan 430073 (China); Li, Zili [The State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070 (China); Wang, Weimin, E-mail: wangwm@hotmail.com [The State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070 (China); Fu, Zhengyi [The State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070 (China)

    2013-06-01

    Graphical abstract: Nano-sized amorphous boron powders were synthesized by active dilution self-propagating high-temperature synthesis (SHS) method. The effects of endothermic reaction rate, the possible chemical reaction mechanism and active dilution model for synthesis of the product were also discussed. Highlights: ► Nano-sized amorphous boron powders were synthesized by active dilution self-propagating high-temperature synthesis method. ► The morphology, particle size and purity of the samples could be effectively controlled via changing the endothermic rate. ► The diluter KBH{sub 4} played an important role in active dilution synthesis of amorphous nano-sized boron powders. ► The active dilution method could be further popularized and become a common approach to prepare various inorganic materials. - Abstract: Nano-sized amorphous boron powders were synthesized by active dilution self-propagating high-temperature synthesis (SHS) method at temperatures ranging from 700 °C to 850 °C in a SHS furnace using Mg, B{sub 2}O{sub 3} and KBH{sub 4} as raw materials. Samples were characterized by X-ray powder diffraction (XRD), Laser particle size analyzer, Fourier transform infrared spectra (FTIR), X-ray energy dispersive spectroscopy (EDX), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and high-resolution transmission TEM (HRTEM). The boron powders demonstrated an average particle size of 50 nm with a purity of 95.64 wt.%. The diluter KBH{sub 4} played an important role in the active dilution synthesis of amorphous nano-sized boron powders. The effects of endothermic reaction rate, the possible chemical reaction mechanism and active dilution model for synthesis of the product were also discussed.

  2. Synthesis of nano-sized amorphous boron powders through active dilution self-propagating high-temperature synthesis method

    International Nuclear Information System (INIS)

    Wang, Jilin; Gu, Yunle; Li, Zili; Wang, Weimin; Fu, Zhengyi

    2013-01-01

    Graphical abstract: Nano-sized amorphous boron powders were synthesized by active dilution self-propagating high-temperature synthesis (SHS) method. The effects of endothermic reaction rate, the possible chemical reaction mechanism and active dilution model for synthesis of the product were also discussed. Highlights: ► Nano-sized amorphous boron powders were synthesized by active dilution self-propagating high-temperature synthesis method. ► The morphology, particle size and purity of the samples could be effectively controlled via changing the endothermic rate. ► The diluter KBH 4 played an important role in active dilution synthesis of amorphous nano-sized boron powders. ► The active dilution method could be further popularized and become a common approach to prepare various inorganic materials. - Abstract: Nano-sized amorphous boron powders were synthesized by active dilution self-propagating high-temperature synthesis (SHS) method at temperatures ranging from 700 °C to 850 °C in a SHS furnace using Mg, B 2 O 3 and KBH 4 as raw materials. Samples were characterized by X-ray powder diffraction (XRD), Laser particle size analyzer, Fourier transform infrared spectra (FTIR), X-ray energy dispersive spectroscopy (EDX), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and high-resolution transmission TEM (HRTEM). The boron powders demonstrated an average particle size of 50 nm with a purity of 95.64 wt.%. The diluter KBH 4 played an important role in the active dilution synthesis of amorphous nano-sized boron powders. The effects of endothermic reaction rate, the possible chemical reaction mechanism and active dilution model for synthesis of the product were also discussed

  3. Elia Kazan's America America: A Message for America.

    Science.gov (United States)

    Molofsky, Merle

    2018-06-01

    Elia Kazan's 1963 film, America America is a tribute to the immigrant experience of his own forebears, and has relevance to the refugee crisis of today. In stark black and white cinematography, the film provides insight into the refugee-immigrant experience, personified in Stavros, a young man longing for freedom, obsessed with an idealized America. His hope and innocence cannot safeguard him. His memories of his happy childhood and loving family create idealizing transferences to a world of others who manipulate and betray him as he undertakes his quest. Eventually he too learns to manipulate and betray, unconsciously identifying with the aggressor. History will offer ethical challenges, the black and white cinematography mirroring the black and white perception of good and bad, the shades of grey evoking a maturation of understanding.

  4. Oxidation of boron carbide at high temperatures

    International Nuclear Information System (INIS)

    Steinbrueck, Martin

    2005-01-01

    The oxidation kinetics of various types of boron carbides (pellets, powder) were investigated in the temperature range between 1073 and 1873 K. Oxidation rates were measured in transient and isothermal tests by means of mass spectrometric gas analysis. Oxidation of boron carbide is controlled by the formation of superficial liquid boron oxide and its loss due to the reaction with surplus steam to volatile boric acids and/or direct evaporation at temperatures above 1770 K. The overall reaction kinetics is paralinear. Linear oxidation kinetics established soon after the initiation of oxidation under the test conditions described in this report. Oxidation is strongly influenced by the thermohydraulic boundary conditions and in particular by the steam partial pressure and flow rate. On the other hand, the microstructure of the B 4 C samples has a limited influence on oxidation. Very low amounts of methane were produced in these tests

  5. The ternary system nickel-boron-silicon

    International Nuclear Information System (INIS)

    Lugscheider, E.; Reimann, H.; Knotek, O.

    1975-01-01

    The ternary system Nickel-Boron-Silicon was established at 850 0 C by means of X-ray diffraction, metallographic and micro-hardness examinations. The well known binary nickel borides and silicides resp. were confirmed. In the boron-silicon system two binary phases, SiBsub(4-x) with x approximately 0.7 and SiB 6 were found the latter in equilibrium with the β-rhombohedral boron. Confirming the two ternary silicon borides a greater homogeneity range was found for Ni 6 Si 2 B, the phase Nisub(4,6)Si 2 B published by Uraz and Rundqvist can better be described by the formula Nisub(4.29)Si 2 Bsub(1.43). In relation to further investigations we measured melting temperatures in ternary Ni-10 B-Si alloys by differential thermoanalysis. (author)

  6. Depth resolved investigations of boron implanted silicon

    Science.gov (United States)

    Sztucki, M.; Metzger, T. H.; Milita, S.; Berberich, F.; Schell, N.; Rouvière, J. L.; Patel, J.

    2003-01-01

    We have studied the depth distribution and structure of defects in boron implanted silicon (0 0 1). Silicon wafers were implanted with a boron dose of 6×10 15 ions/cm -2 at 32 keV and went through different annealing treatments. Using diffuse X-ray scattering at grazing incidence and exit angles we are able to distinguish between different kinds of defects (point defect clusters and extrinsic stacking faults on {1 1 1} planes) and to determine their depth distribution as a function of the thermal budget. Cross-section transmission electron microscopy was used to gain complementary information. In addition we have determined the strain distribution caused by the boron implantation as a function of depth from rocking curve measurements.

  7. Radiation hardening of MOS devices by boron

    International Nuclear Information System (INIS)

    Danchenko, V.

    1975-01-01

    A novel technique is disclosed for radiation hardening of MOS devices and specifically for stabilizing the gate threshold potential at room temperature of a radiation subjected MOS field-effect device of the type having a semiconductor substrate, an insulating layer of oxide on the substrate, and a gate electrode disposed on the insulating layer. In the preferred embodiment, the novel inventive technique contemplates the introduction of boron into the insulating oxide, the boron being introduced within a layer of the oxide of about 100A to 300A thickness immediately adjacent the semiconductor-insulator interface. The concentration of boron in the oxide layer is preferably maintained on the order of 10 atoms/ cm 3 . The novel technique serves to reduce and substantially annihilate radiation induced positive gate charge accumulations, which accumulations, if not eliminated, would cause shifting of the gate threshold potential of a radiation subjected MOS device, and thus render the device unstable and/or inoperative. (auth)

  8. BC-454 boron-loaded plastic scintillator

    International Nuclear Information System (INIS)

    Bellian, J.G.

    1984-01-01

    Prototype samples of plastic scintillators containing up to 10% by weight of natural boron have been produced. The maximum size scintillators made to date are 28 mm dia. x 100 mm long. Rods containing up to 2% boron are now made routinely and work is progressing on higher concentrations. The plastics are clear and emit the same blue fluorescence as other common plastic scintillators. It is expected that rods up to 3'' dia. containing 5% boron will be produced during the next few months. BC-454 is particularly useful in neutron research, materials studies, some types of neutron dosimetry, and monitoring of medium to high energy neutrons in the presence of other types radiation. It combines attractive features that enhance its usefulness to the physics community

  9. On the Mechanism of Boron Ignition

    Science.gov (United States)

    Keil, D. G.; Dreizin, E. L.; Felder, W.; Vicenzi, E. P.

    1997-01-01

    Boron filaments were electrically heated in air and argon/oxygen mixtures while their resistance, temperature, and radiation at the wavelengths of BO and BO2 bands were monitored. The filaments 'burned' in two distinct stages. Samples of the filaments were quenched at different times before and during the burning and analyzed using electron microscopy. The beginning of the first stage combustion characterized by a local resistance minimum, a sharp spike in boron oxide radiation emission, and a rapid rise in temperature, occurred at 1500 +/- 70 deg. C, independent of pre-heating history and oxygen content (540%) in the gas environment. The data suggest that a phase transition occurs in the filaments at this temperature that triggers stage one combustion. Significant amounts of oxygen were found inside quenched filaments. Large spherical voids formed in the boron filaments during their second stage combustion which is interpreted to indicate a crucial role for the gas dissolution processes in the combustion scenario.

  10. A system to deposit boron films (boronization) in the DIII-D tokamak

    International Nuclear Information System (INIS)

    Hodapp, T.R.; Jackson, G.L.; Phillips, J.; Holtrop, K.L.; Peterson, P.L.; Winters, J.

    1992-01-01

    A system has been added to the DIII-D tokamak to coat its plasma facing surfaces with a film of boron using diborane gas. The system includes special health and safety equipment for handling the diborane gas which is toxic and inflammable. The purpose f the boron film is to reduce the levels of impurity atoms in the DIII-D plasmas. Experiments following the application of the boron film in DIII-D have led to significant reductions in plasma impurity levels and the observation of a new, very high confinement regime

  11. A system to deposit boron films (boronization) in the DIII-D tokamak

    International Nuclear Information System (INIS)

    Hodapp, T.R.; Jackson, G.L.; Phillips, J.; Holtrop, K.L.; Petersen, P.I.; Winter, J.

    1991-09-01

    A system has been added to the D3-D tokamak to coat its plasma facing surfaces with a film of boron using diborane gas. The system includes special health and safety equipment for handling the diborane gas which is toxic and inflammable. The purpose of the boron film is to reduce the levels of impurity atoms in the D3-D plasmas. Experiments following the application of the boron film in D3-D have led to significant reductions in plasma impurity levels and the observation of a new, very high confinement regime. 9 refs., 1 fig

  12. New long-cycle small modular PWR cores using particle type burnable poisons for low boron operation

    Energy Technology Data Exchange (ETDEWEB)

    Yoo, Hoseong; Hwang, Dae Hee [Department of Nuclear Engineering, Kyung Hee University, Deogyeong-daero, GiHeung-gu, Yongin, Gyeonggi-do 446-701 (Korea, Republic of); Hong, Ser Gi, E-mail: sergihong@khu.ac.kr [Department of Nuclear Engineering, Kyung Hee University, Deogyeong-daero, GiHeung-gu, Yongin, Gyeonggi-do 446-701 (Korea, Republic of); Shin, Ho Choel [Core and Fuel Analysis Group, Korea Hydro & Nuclear Power Central Research Institute (KHNP-CRI), Daejon 305-343 (Korea, Republic of)

    2017-04-01

    Highlights: • New advanced burnable poison rods (BPR) are suggested for low boron operation in PWR. • The new SMR cores have long cycle length of ∼4.5 EFPYs with low boron concentration. • The SMR core satisfies all the design targets and constraints. - Abstract: In this paper, new small long-cycle PWR (Pressurized Water Reactor) cores for low boron concentration operation are designed by employing advanced burnable poison rods (BPRs) in which the BISO (Bi-Isotropic) particles of burnable poison are distributed in a SiC matrix. The BPRs are designed by adjusting the kernel diameter, the kernel material and the packing fraction to effectively reduce the excess reactivity in order to reduce the boron concentration in the coolant and achieve a flat change in excess reactivity over a long operational cycle. In addition, axial zoning of the BPRs was suggested to improve the core performances, and it was shown that the suggested axial zoning of BPRs considerably extends the cycle length compared to a core with no BPR axial zoning. The results of the core physics analyses showed that the cores using BPRs with a B{sub 4}C kernel have long cycle lengths of ∼4.5 EFPYs (Effective Full Power Years), small maximum CBCs (Critical Boron Concentration) lower than 370 ppm, low power peaking factors, and large shutdown margins of control element assemblies.

  13. Knowledge acquisition for temporal abstraction.

    Science.gov (United States)

    Stein, A; Musen, M A; Shahar, Y

    1996-01-01

    Temporal abstraction is the task of detecting relevant patterns in data over time. The knowledge-based temporal-abstraction method uses knowledge about a clinical domain's contexts, external events, and parameters to create meaningful interval-based abstractions from raw time-stamped clinical data. In this paper, we describe the acquisition and maintenance of domain-specific temporal-abstraction knowledge. Using the PROTEGE-II framework, we have designed a graphical tool for acquiring temporal knowledge directly from expert physicians, maintaining the knowledge in a sharable form, and converting the knowledge into a suitable format for use by an appropriate problem-solving method. In initial tests, the tool offered significant gains in our ability to rapidly acquire temporal knowledge and to use that knowledge to perform automated temporal reasoning.

  14. Boron removal by electrocoagulation and recovery.

    Science.gov (United States)

    Isa, Mohamed Hasnain; Ezechi, Ezerie Henry; Ahmed, Zubair; Magram, Saleh Faraj; Kutty, Shamsul Rahman Mohamed

    2014-03-15

    This work investigated the removal of boron from wastewater and its recovery by electrocoagulation and hydrothermal mineralization methods respectively. The experimental design was developed using Box-Behnken Model. An initial study was performed based on four preselected variables (pH, current density, concentration and time) using synthetic wastewater. Response surface methodology (RSM) was used to evaluate the effect of process variables and their interaction on boron removal. The optimum conditions were obtained as pH 6.3, current density 17.4 mA/cm(2), and time 89 min. At these applied optimum conditions, 99.7% boron removal from an initial concentration of 10.4 mg/L was achieved. The process was effectively optimized by RSM with a desirability value of 1.0. The results showed that boron removal efficiency enhanced with increase in current density and treatment time. Removal efficiency also increased when pH was increased from 4 to 7 and subsequently decreased at pH 10. Adsorption kinetics study revealed that the reaction followed pseudo second order kinetic model; evidenced by high correlation and goodness of fit. Thermodynamics study showed that mechanism of boron adsorption was chemisorption and the reaction was endothermic in nature. Furthermore, the adsorption process was spontaneous as indicated by negative values of the adsorption free energy. Treatment of real produced water using electrocoagulation resulted in 98% boron removal. The hydrothermal mineralization study showed that borate minerals (Inyoite, Takadaite and Nifontovite) can be recovered as recyclable precipitate from electrocoagulation flocs of produced water. Copyright © 2013 Elsevier Ltd. All rights reserved.

  15. Boron nitride nanotubes for spintronics.

    Science.gov (United States)

    Dhungana, Kamal B; Pati, Ranjit

    2014-09-22

    With the end of Moore's law in sight, researchers are in search of an alternative approach to manipulate information. Spintronics or spin-based electronics, which uses the spin state of electrons to store, process and communicate information, offers exciting opportunities to sustain the current growth in the information industry. For example, the discovery of the giant magneto resistance (GMR) effect, which provides the foundation behind modern high density data storage devices, is an important success story of spintronics; GMR-based sensors have wide applications, ranging from automotive industry to biology. In recent years, with the tremendous progress in nanotechnology, spintronics has crossed the boundary of conventional, all metallic, solid state multi-layered structures to reach a new frontier, where nanostructures provide a pathway for the spin-carriers. Different materials such as organic and inorganic nanostructures are explored for possible applications in spintronics. In this short review, we focus on the boron nitride nanotube (BNNT), which has recently been explored for possible applications in spintronics. Unlike many organic materials, BNNTs offer higher thermal stability and higher resistance to oxidation. It has been reported that the metal-free fluorinated BNNT exhibits long range ferromagnetic spin ordering, which is stable at a temperature much higher than room temperature. Due to their large band gap, BNNTs are also explored as a tunnel magneto resistance device. In addition, the F-BNNT has recently been predicted as an ideal spin-filter. The purpose of this review is to highlight these recent progresses so that a concerted effort by both experimentalists and theorists can be carried out in the future to realize the true potential of BNNT-based spintronics.

  16. Boron Nitride Nanotubes for Spintronics

    Directory of Open Access Journals (Sweden)

    Kamal B. Dhungana

    2014-09-01

    Full Text Available With the end of Moore’s law in sight, researchers are in search of an alternative approach to manipulate information. Spintronics or spin-based electronics, which uses the spin state of electrons to store, process and communicate information, offers exciting opportunities to sustain the current growth in the information industry. For example, the discovery of the giant magneto resistance (GMR effect, which provides the foundation behind modern high density data storage devices, is an important success story of spintronics; GMR-based sensors have wide applications, ranging from automotive industry to biology. In recent years, with the tremendous progress in nanotechnology, spintronics has crossed the boundary of conventional, all metallic, solid state multi-layered structures to reach a new frontier, where nanostructures provide a pathway for the spin-carriers. Different materials such as organic and inorganic nanostructures are explored for possible applications in spintronics. In this short review, we focus on the boron nitride nanotube (BNNT, which has recently been explored for possible applications in spintronics. Unlike many organic materials, BNNTs offer higher thermal stability and higher resistance to oxidation. It has been reported that the metal-free fluorinated BNNT exhibits long range ferromagnetic spin ordering, which is stable at a temperature much higher than room temperature. Due to their large band gap, BNNTs are also explored as a tunnel magneto resistance device. In addition, the F-BNNT has recently been predicted as an ideal spin-filter. The purpose of this review is to highlight these recent progresses so that a concerted effort by both experimentalists and theorists can be carried out in the future to realize the true potential of BNNT-based spintronics.

  17. The Immunosuppressive drug – Rapamycin – Electroanalytical Sensing Using Boron- Doped Diamond electrode

    International Nuclear Information System (INIS)

    Stanković, Dalibor M.; Kalcher, Kurt

    2015-01-01

    Graphical abstract: Display Omitted -- Abstract: This paper presents for the first time the study of electrochemical behavior of well known immunosuppressant drug – rapamycin (sirolimus) using boron-doped diamond electrode. Rapamycin provided single and oval-shaped oxidation peak at +1.1 V vs. Ag/AgCl electrode in Britton–Robinson buffer solution at pH 3 confirming highly irreversible behavior of analyte at boron-doped diamond electrode. A differential pulse voltammetry was used for quantification of tested drug under the optimum experimental conditions. The calibration curve was linear over the range from 0.5 to 19.5 μM (R 2 = 0.9976) with detection limit of 0.22 μM. Repeatability of ten successfully measurements of three different concentrations (5, 10 and 15 μM) was 2.5, 1.9 and 1,7 %, respectively. Influence of most common biomolecules presented in urine samples was evaluated. The suggested analytical methodology was successfully applied for determination of rapamycin in four urine samples with excellent recoveries. The developed approach could be beneficial in analysis of rapamycin in biological samples using boron-doped diamond electrode as up-to-date electrochemical sensor and could represent inexpensive analytical alternative to separation methods

  18. Reactive sputter deposition of boron nitride

    International Nuclear Information System (INIS)

    Jankowski, A.F.; Hayes, J.P.; McKernan, M.A.; Makowiecki, D.M.

    1995-10-01

    The preparation of fully dense, boron targets for use in planar magnetron sources has lead to the synthesis of Boron Nitride (BN) films by reactive rf sputtering. The deposition parameters of gas pressure, flow and composition are varied along with substrate temperature and applied bias. The films are characterized for composition using Auger electron spectroscopy, for chemical bonding using Raman spectroscopy and for crystalline structure using transmission electron microscopy. The deposition conditions are established which lead to the growth of crystalline BN phases. In particular, the growth of an adherent cubic BN coating requires 400--500 C substrate heating and an applied -300 V dc bias

  19. Proton linacs for boron neutron capture therapy

    International Nuclear Information System (INIS)

    Lennox, A.J.

    1993-08-01

    Recent advances in the ability to deliver boron-containing drugs to brain tumors have generated interest in ∼4 MeV linacs as sources of epithermal neutrons for radiation therapy. In addition, fast neutron therapy facilities have been studying methods to moderate their beams to take advantage of the high cross section for epithermal neutrons on boron-10. This paper describes the technical issues involved in each approach and presents the motivation for undertaking such studies using the Fermilab linac. the problems which must be solved before therapy can begin are outlined. Status of preparatory work and results of preliminary measurements are presented

  20. Titanium reinforced boron-polyimide composite

    Science.gov (United States)

    Clark, G. A.; Clayton, K. I.

    1969-01-01

    Processing techniques for boron polyimide prepreg were developed whereby composites could be molded under vacuum bag pressure only. A post-cure cycle was developed which resulted in no loss in room temperature mechanical properties of the composite at any time during up to 16 hours at 650 F. A design utilizing laminated titanium foil was developed to achieve a smooth transition of load from the titanium attachment points into the boron-reinforced body of the structure. The box beam test article was subjected to combined bending and torsional loads while exposed to 650 F. Loads were applied incrementally until failure occurred at 83% design limit load.

  1. Designing your boron-charging system

    International Nuclear Information System (INIS)

    Miller, J.

    1979-01-01

    High-pressure positive-displacement pumps used in the boron-charging setups of pressurized-water (PWR) nuclear plants because of their inherently high efficiencies over a wide range of pressures and speeds are described. Hydrogen-saturated water containing 4-12% boric acid is fed to the pump from a volume-control tank under a gas blanket. Complicated piping and the pulsation difficulties associated with reciprocating pumps make hydrogen-saturated boron-charging systems a challenge to the designer. The article describes the unusual hydraulics of the systems to help assure a trouble-free design

  2. Model for calculating the boron concentration in PWR type reactors

    International Nuclear Information System (INIS)

    Reis Martins Junior, L.L. dos; Vanni, E.A.

    1986-01-01

    A PWR boron concentration model has been developed for use with RETRAN code. The concentration model calculates the boron mass balance in the primary circuit as the injected boron mixes and is transported through the same circuit. RETRAN control blocks are used to calculate the boron concentration in fluid volumes during steady-state and transient conditions. The boron reactivity worth is obtained from the core concentration and used in RETRAN point kinetics model. A FSAR type analysis of a Steam Line Break Accident in Angra I plant was selected to test the model and the results obtained indicate a sucessfull performance. (Author) [pt

  3. Hemorrhage in mouse tumors induced by dodecaborate cluster lipids intended for boron neutron capture therapy

    Directory of Open Access Journals (Sweden)

    Schaffran T

    2014-07-01

    Full Text Available Tanja Schaffran,1 Nan Jiang,1 Markus Bergmann,2,3 Ekkehard Küstermann,4 Regine Süss,5 Rolf Schubert,5 Franz M Wagner,6 Doaa Awad,7 Detlef Gabel1,2,8 1Department of Chemistry, University of Bremen, 2Institute of Neuropathology, Klinikum Bremen-Mitte; 3Cooperative Center Medicine, University of Bremen, 4“In-vivo-MR” AG, FB2, University of Bremen, Bremen, 5Pharmaceutical Technology, University of Freiburg, Freiburg im Breisgau, 6Forschungsneutronenquelle Heinz Maier-Leibnitz (FRM II, Technische Unversitaet Muenchen, Garching, Germany; 7Department of Biochemistry, Alexandria University, Alexandria, Egypt; 8School of Engineering and Science, Jacobs University Bremen, Bremen, Germany Abstract: The potential of boron-containing lipids with three different structures, which were intended for use in boron neutron capture therapy, was investigated. All three types of boron lipids contained the anionic dodecaborate cluster as the headgroup. Their effects on two different tumor models in mice following intravenous injection were tested; for this, liposomes with boron lipid, distearoyl phosphatidylcholine, and cholesterol as helper lipids, and containing a polyethylene glycol lipid for steric protection, were administered intravenously into tumor-bearing mice (C3H mice for SCCVII squamous cell carcinoma and BALB/c mice for CT26/WT colon carcinoma. With the exception of one lipid (B-THF-14, the lipids were well tolerated, and no other animal was lost due to systemic toxicity. The lipid which led to death was not found to be much more toxic in cell culture than the other boron lipids. All of the lipids that were well tolerated showed hemorrhage in both tumor models within a few hours after administration. The hemorrhage could be seen by in vivo magnetic resonance and histology, and was found to occur within a few hours. The degree of hemorrhage depended on the amount of boron administered and on the tumor model. The observed unwanted effect of the lipids

  4. Synthesis of boron nitride nanotubes with SiC nanowire as template

    International Nuclear Information System (INIS)

    Zhong, B.; Song, L.; Huang, X.X.; Wen, G.W.; Xia, L.

    2011-01-01

    Highlights: → Boron nitride nanotubes (BNNTs) have been fabricated using SiC nanowires as template. → SiC nanowires could be effectively etched out by the vapors decomposed from ammonia borane, leading to the formation of BNNTs. → A template self-sacrificing mechanism is responsible for the formation of BNNTs. -- Abstract: A novel template method for the preparation of boron nitride nanotubes (BNNTs) using SiC nanowire as template and ammonia borane as precursor is reported. We find out that the SiC nanowires could be effectively etched out by the vapors decomposed from ammonia borane, leading to the formation of BNNTs. The as-prepared products are well characterized by means of complementary analytical techniques. A possible formation mechanism is disclosed. The method developed here paves the way for large scale production of BNNTs.

  5. Insights into the Mechanisms Underlying Boron Homeostasis in Plants

    Directory of Open Access Journals (Sweden)

    Akira Yoshinari

    2017-11-01

    Full Text Available Boron is an essential element for plants but is toxic in excess. Therefore, plants must adapt to both limiting and excess boron conditions for normal growth. Boron transport in plants is primarily based on three transport mechanisms across the plasma membrane: passive diffusion of boric acid, facilitated diffusion of boric acid via channels, and export of borate anion via transporters. Under boron -limiting conditions, boric acid channels and borate exporters function in the uptake and translocation of boron to support growth of various plant species. In Arabidopsis thaliana, NIP5;1 and BOR1 are located in the plasma membrane and polarized toward soil and stele, respectively, in various root cells, for efficient transport of boron from the soil to the stele. Importantly, sufficient levels of boron induce downregulation of NIP5;1 and BOR1 through mRNA degradation and proteolysis through endocytosis, respectively. In addition, borate exporters, such as Arabidopsis BOR4 and barley Bot1, function in boron exclusion from tissues and cells under conditions of excess boron. Thus, plants actively regulate intracellular localization and abundance of transport proteins to maintain boron homeostasis. In this review, the physiological roles and regulatory mechanisms of intracellular localization and abundance of boron transport proteins are discussed.

  6. A colorimetric determination of boron in biological sample for boron neutron capture therapy (BNCT)

    International Nuclear Information System (INIS)

    Camillo, M.A.P.; Tomac Junior, U.

    1990-01-01

    The boron neutron capture therapy (BNCT) has shown better prognosis in the treatment of glyemas and gluoblastomas grade III and IV than other therapies. During the treatment the levels of Na 2 10 B 12 H 11 SH must be known in several compartiments of the organism and with this purpose the method of colorimetric determination of boron using curcumine was established. This method is simple, reprodutible and adequate sensitivity for this control. (author) [pt

  7. A colorimetric determination of boron in biological sample for boron neutron capture therapy

    International Nuclear Information System (INIS)

    Camilo, M.A.P.; Tomac Junior, U.

    1989-01-01

    The boron neutron capture therapy (BNCT) has shown better prognosis in the treatment of gliomas and glioblastomas grade III and IV than other therapies. During the treatment of levels of Na 2 10 B 12 H 11 S H must be known in several compartments of the organism and with this purpose the method of colorimetric determination of boron using curcumin was established. This method is simples, reproducible and has adequate sensitivity for this control. (author). 7 refs, 3 figs, 1 tab

  8. Boron uptake measurements in a rat model for Boron Neutron Capture Therapy of lung tumours

    Energy Technology Data Exchange (ETDEWEB)

    Bortolussi, S., E-mail: silva.bortolussi@pv.infn.i [Department of Nuclear and Theoretical Physics, University of Pavia, via Bassi 6, 27100 Pavia (Italy); National Institute of Nuclear Physics (INFN), Section of Pavia, via Bassi 6, 27100 Pavia (Italy); Bakeine, J.G. [Department of Nuclear and Theoretical Physics, University of Pavia, via Bassi 6, 27100 Pavia (Italy); Ballarini, F. [Department of Nuclear and Theoretical Physics, University of Pavia, via Bassi 6, 27100 Pavia (Italy); National Institute of Nuclear Physics (INFN), Section of Pavia, via Bassi 6, 27100 Pavia (Italy); Bruschi, P. [Department of Nuclear and Theoretical Physics, University of Pavia, via Bassi 6, 27100 Pavia (Italy); Gadan, M.A. [Department of Nuclear and Theoretical Physics, University of Pavia, via Bassi 6, 27100 Pavia (Italy); Comision Nacional de Energia Atomica, Buenos Aires (Argentina); Protti, N.; Stella, S. [Department of Nuclear and Theoretical Physics, University of Pavia, via Bassi 6, 27100 Pavia (Italy); National Institute of Nuclear Physics (INFN), Section of Pavia, via Bassi 6, 27100 Pavia (Italy); Clerici, A.; Ferrari, C.; Cansolino, L.; Zonta, C.; Zonta, A. [Department of Surgery, University of Pavia, via Ferrata 27100 Pavia (Italy); Nano, R. [Department of Animal Biology, University of Pavia, via Ferrata 27100 Pavia (Italy); Altieri, S. [Department of Nuclear and Theoretical Physics, University of Pavia, via Bassi 6, 27100 Pavia (Italy); National Institute of Nuclear Physics (INFN), Section of Pavia, via Bassi 6, 27100 Pavia (Italy)

    2011-02-15

    Lung carcinoma is the leading cause of cancer mortality in the Western countries. Despite the introduction over the last few years of new therapeutic agents, survival from lung cancer has shown no discernible improvement in the last 20 years. For these reasons any efforts to find and validate new effective therapeutic procedures for lung cancer are very timely. The selective boron uptake in the tumour with respect to healthy tissues makes Boron Neutron Capture Therapy a potentially advantageous option in the treatment of tumours that affect whole vital organs, and that are surgically inoperable. To study the possibility of applying BNCT to the treatment of diffuse pulmonary tumours, an animal model for boron uptake measurements in lung metastases was developed. Both healthy and tumour-bearing rats were infused with Boronophenylalanine (BPA) and sacrificed at different time intervals after drug administration. The lungs were extracted, and prepared for boron analysis by neutron autoradiography and {alpha}-spectroscopy. The boron concentrations in tumour and normal lung were plotted as a function of the time elapsed after BPA administration. The concentration in tumour is almost constant within the error bars for all the time intervals of the experiment (1-8 h), while the curve in normal lung decreases after 4 h from BPA infusion. At 4 h, the ratio of boron concentration in tumour to boron concentration in healthy lung is higher than 3, and it stays above this level up to 8 h. Also the images of boron distribution in the samples, obtained by neutron autoradiography, show a selective absorption in the metastases.

  9. Nuclear magnetic resonance spectroscopy of boron compounds containing two-, three- and four-coordinate boron

    International Nuclear Information System (INIS)

    Wrackmeyer, B.

    1988-01-01

    The influence of boron chemistry on various areas of research in inorganic, organic and theoretical chemistry is well documented. In fact, many models presently employed to describe chemical bonding in general can be traced to attempts to understand bonding in boranes. The confirmation of many theoretical predictions in boron chemistry relies on direct and indirect structural information provided by various physical methods that - fortunately - became available almost at the same rate as that with which the interest in boron compounds was growing. Clearly, there has always been a strong link between the interest in synthesis and the application of physical methods. As in many other areas of chemistry, developments in boron chemistry have been greatly accelerated by NMR. 11 B NMR has been at the center of interest from the beginning, accompanied by routine 1 H NMR measurements, and occasional 14 N, 19 F and 31 P NMR work. In the last 12 years, we have seen an increasing number of 13 C NMR studies of boron compounds. The availability of multinuclear facilities for PFT NMR spectrometers stimulates the measurement of the NMR spectra of other nuclei, like 29 Si, 119 Sn or other metals, in order to obtain additional information. This paper is intended to serve several purposes: to update previous reviews on 11 B NMR of boron compounds, to demonstrate some applications of multinuclear NMR to boron chemistry; to attempt to incorporate new NMR parameters into the known data set; and to summarize the experimental facts required for obtaining the maximum information from NMR studies on boron compounds

  10. Construct Abstraction for Automatic Information Abstraction from Digital Images

    Science.gov (United States)

    2006-05-30

    objects and features and the names of objects of objects and features. For example, in Figure 15 the parts of the fish could be named the ‘mouth... fish -1 fish -2 fish -3 tennis shoe tennis racquet...of abstraction and generality. For example, an algorithm might usefully find a polygon ( blob ) in an image and calculate numbers such as the

  11. ICP-MS determination of boron: method optimization during preparation of graphite reference material for boron

    International Nuclear Information System (INIS)

    Granthali, S.K.; Shailaja, P.P.; Mainsha, V.; Venkatesh, K.; Kallola, K.S.; Sanjukta, A.K.

    2017-01-01

    Graphite finds widespread use in nuclear reactors as moderator, reflector, and fuel fabricating components because of its thermal stability and integrity. The manufacturing process consists of various mixing, moulding and baking operations followed by heat-treatment between 2500 °C and 3000 °C. The high temperature treatment is required to drive the amorphous carbon-to-graphite phase transformation. Since synthetic graphite is processed at high temperature, impurity concentrations in the precursor carbon get significantly reduced due to volatilization. However boron may might partly gets converted into boron carbide at high temperatures in the carbon environment of graphite and remains stable (B_4C: boiling point 3500 °C) in the matrix. Literature survey reveals the use of various methods for determination of boron. Previously we have developed a method for determination of boron in graphite electrodes using inductively coupled plasma mass spectrometry (ICP-MS). The method involves removal of graphite matrix by ignition of the sample at 800°C in presence of saturated barium hydroxide solution to prevent the loss of boron. Here we are reporting a modification in the method by using calcium carbonate in place of barium hydroxide and using beryllium (Be) as an internal standard, which resulted in a better precession. The method was validated by spike recovery experiments as well as using another technique viz. Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES). The modified method was applied in evaluation of boron concentration in the graphite reference material prepared

  12. Boron exposure through drinking water during pregnancy and birth size.

    Science.gov (United States)

    Igra, Annachiara Malin; Harari, Florencia; Lu, Ying; Casimiro, Esperanza; Vahter, Marie

    2016-10-01

    Boron is a metalloid found at highly varying concentrations in soil and water. Experimental data indicate that boron is a developmental toxicant, but the few human toxicity data available concern mostly male reproduction. To evaluate potential effects of boron exposure through drinking water on pregnancy outcomes. In a mother-child cohort in northern Argentina (n=194), 1-3 samples of serum, whole blood and urine were collected per woman during pregnancy and analyzed for boron and other elements to which exposure occurred, using inductively coupled plasma mass spectrometry. Infant weight, length and head circumference were measured at birth. Drinking water boron ranged 377-10,929μg/L. The serum boron concentrations during pregnancy ranged 0.73-605μg/L (median 133μg/L) and correlated strongly with whole-blood and urinary boron, and, to a lesser extent, with water boron. In multivariable-adjusted linear spline regression analysis (non-linear association), we found that serum boron concentrations above 80μg/L were inversely associated with birth length (B-0.69cm, 95% CI -1.4; -0.024, p=0.043, per 100μg/L increase in serum boron). The impact of boron appeared stronger when we restricted the exposure to the third trimester, when the serum boron concentrations were the highest (0.73-447μg/L). An increase in serum boron of 100μg/L in the third trimester corresponded to 0.9cm shorter and 120g lighter newborns (p=0.001 and 0.021, respectively). Considering that elevated boron concentrations in drinking water are common in many areas of the world, although more screening is warranted, our novel findings warrant additional research on early-life exposure in other populations. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  13. Mechanical Engineering Department technical abstracts

    International Nuclear Information System (INIS)

    1984-01-01

    The Mechanical Engineering Department publishes abstracts twice a year to inform readers of the broad range of technical activities in the Department, and to promote an exchange of ideas. Details of the work covered by an abstract may be obtained by contacting the author(s). General information about the current role and activities of each of the Department's seven divisions precedes the technical abstracts. Further information about a division's work may be obtained from the division leader, whose name is given at the end of each divisional summary. The Department's seven divisions are as follows: Nuclear Test Engineering Division, Nuclear Explosives Engineering Division, Weapons Engineering Division, Energy Systems Engineering Division, Engineering Sciences Division, Magnetic Fusion Engineering Division and Materials Fabrication Division

  14. Abstraction by Set-Membership

    DEFF Research Database (Denmark)

    Mödersheim, Sebastian Alexander

    2010-01-01

    The abstraction and over-approximation of protocols and web services by a set of Horn clauses is a very successful method in practice. It has however limitations for protocols and web services that are based on databases of keys, contracts, or even access rights, where revocation is possible, so...... that the set of true facts does not monotonically grow with the transitions. We extend the scope of these over-approximation methods by defining a new way of abstraction that can handle such databases, and we formally prove that the abstraction is sound. We realize a translator from a convenient specification...... language to standard Horn clauses and use the verifier ProVerif and the theorem prover SPASS to solve them. We show by a number of examples that this approach is practically feasible for wide variety of verification problems of security protocols and web services....

  15. Boron nitride nanosheets reinforced glass matrix composites

    Czech Academy of Sciences Publication Activity Database

    Saggar, Richa; Porwal, H.; Tatarko, P.; Dlouhý, Ivo; Reece, M. J.

    2015-01-01

    Roč. 114, SEP (2015), S26-S32 ISSN 1743-6753 R&D Projects: GA MŠk(CZ) 7AMB14SK155 EU Projects: European Commission(XE) 264526 Institutional support: RVO:68081723 Keywords : Boron nitride nanosheets * Borosilicate glass * Mechanical properties Subject RIV: JL - Materials Fatigue, Friction Mechanics Impact factor: 1.162, year: 2015

  16. Boron-doped manganese dioxide for supercapacitors.

    Science.gov (United States)

    Chi, Hong Zhong; Li, Yuwei; Xin, Yingxu; Qin, Haiying

    2014-11-11

    The addition of boron as a dopant during the reaction between carbon fiber and permanganate led to significant enhancement of the growth-rate and formation of the porous framework. The doped MnO2 was superior to the pristine sample as electrode materials for supercapacitors in terms of the specific capacitance and rate capability.

  17. Intrinsic ferromagnetism in hexagonal boron nitride nanosheets

    Energy Technology Data Exchange (ETDEWEB)

    Si, M. S.; Gao, Daqiang, E-mail: gaodq@lzu.edu.cn, E-mail: xueds@lzu.edu.cn; Yang, Dezheng; Peng, Yong; Zhang, Z. Y.; Xue, Desheng, E-mail: gaodq@lzu.edu.cn, E-mail: xueds@lzu.edu.cn [Key Laboratory for Magnetism and Magnetic Materials of the Ministry of Education, Lanzhou University, Lanzhou 730000 (China); Liu, Yushen [Jiangsu Laboratory of Advanced Functional Materials and College of Physics and Engineering, Changshu Institute of Technology, Changshu 215500 (China); Deng, Xiaohui [Department of Physics and Electronic Information Science, Hengyang Normal University, Hengyang 421008 (China); Zhang, G. P. [Department of Physics, Indiana State University, Terre Haute, Indiana 47809 (United States)

    2014-05-28

    Understanding the mechanism of ferromagnetism in hexagonal boron nitride nanosheets, which possess only s and p electrons in comparison with normal ferromagnets based on localized d or f electrons, is a current challenge. In this work, we report an experimental finding that the ferromagnetic coupling is an intrinsic property of hexagonal boron nitride nanosheets, which has never been reported before. Moreover, we further confirm it from ab initio calculations. We show that the measured ferromagnetism should be attributed to the localized π states at edges, where the electron-electron interaction plays the role in this ferromagnetic ordering. More importantly, we demonstrate such edge-induced ferromagnetism causes a high Curie temperature well above room temperature. Our systematical work, including experimental measurements and theoretical confirmation, proves that such unusual room temperature ferromagnetism in hexagonal boron nitride nanosheets is edge-dependent, similar to widely reported graphene-based materials. It is believed that this work will open new perspectives for hexagonal boron nitride spintronic devices.

  18. Anomalous Seebeck coefficient in boron carbides

    International Nuclear Information System (INIS)

    Aselage, T.L.; Emin, D.; Wood, C.; Mackinnon, I.D.R.; Howard, I.A.

    1987-01-01

    Boron carbides exhibit an anomalously large Seebeck coefficient with a temperature coefficient that is characteristic of polaronic hopping between inequivalent sites. The inequivalence in the sites is associated with disorder in the solid. The temperature dependence of the Seebeck coefficient for materials prepared by different techniques provides insight into the nature of the disorder

  19. NEW ADVANCES IN BORON SOIL CHEMISTRY - Paper

    Science.gov (United States)

    Boron is an essential plant micronutrient for which the range between deficiency and toxicity is narrower than for any other nutrient element. Plants respond directly to the amount of B in soil solution and only indirectly to the amount of B adsorbed on soil particle surfaces. ...

  20. NEW ADVANCES IN BORON SOIL CHEMISTRY

    Science.gov (United States)

    Boron is an essential plant micronutrient for which the range between deficiency and toxicity is narrower than for any other nutrient element. Plants respond directly to the amount of B in soil solution and only indirectly to the amount of B adsorbed on soil particle surfaces. ...

  1. New insight into pecan boron nutrition

    Science.gov (United States)

    Alternate bearing by individual pecan [Carya illinoinensis (Wangenh.) K. Koch] trees is problematic for nut producers and processors. There are many unknowns regarding alternate bearing physiology, such as the relationship between boron and fruit set, nutmeat quality, and kernel maladies. Evidence...

  2. Joining of boron carbide using nickel interlayer

    International Nuclear Information System (INIS)

    Vosughi, A.; Hadian, A. M.

    2008-01-01

    Carbide ceramics such as boron carbide due to their unique properties such as low density, high refractoriness, and high strength to weight ratio have many applications in different industries. This study focuses on direct bonding of boron carbide for high temperature applications using nickel interlayer. The process variables such as bonding time, temperature, and pressure have been investigated. The microstructure of the joint area was studied using electron scanning microscope technique. At all the bonding temperatures ranging from 1150 to 1300 d eg C a reaction layer formed across the ceramic/metal interface. The thickness of the reaction layer increased by increasing temperature. The strength of the bonded samples was measured using shear testing method. The highest strength value obtained was about 100 MPa and belonged to the samples bonded at 1250 for 75 min bonding time. The strength of the joints decreased by increasing the bonding temperature above 1250 d eg C . The results of this study showed that direct bonding technique along with nickel interlayer can be successfully utilized for bonding boron carbide ceramic to itself. This method may be used for bonding boron carbide to metals as well.

  3. Influence of pollution of boron chlorinity ratio

    Digital Repository Service at National Institute of Oceanography (India)

    Narvekar, P.V.; Zingde, M.D.

    Presence of boron in domestic wastewater has resulted in high B/CI ratio at some locations in the coastal water around Bombay. A widest range (0.215-0.281) of B/CI was observed at a location with high influence of wastewater release. The mean B...

  4. Bandgap engineered graphene and hexagonal boron nitride

    Indian Academy of Sciences (India)

    In this article a double-barrier resonant tunnelling diode (DBRTD) has been modelled by taking advantage of single-layer hexagonal lattice of graphene and hexagonal boron nitride (h-BN). The DBRTD performance and operation are explored by means of a self-consistent solution inside the non-equilibrium Green's ...

  5. Reaction of boron carbide with molybdenum disilicide

    International Nuclear Information System (INIS)

    Novikov, A.V.; Melekhin, V.F.; Pegov, V.S.

    1989-01-01

    The investigation results of interaction in the B 4 C-MoSi 2 system during sintering in vacuum are presented. Sintering of boron carbide with molybdenum disilicide is shown to lead to the formation of MoB 2 , SiC, Mo 5 Si 3 compounds, the presence of carbon-containing covering plays an important role in sintering

  6. Crystal structure of isomeric boron difluoride acetylnaphtholates

    International Nuclear Information System (INIS)

    Bukvetskij, B.V.; Fedorenko, E.V.; Mirochnik, A.G.; Karasev, V.E.

    2006-01-01

    Crystal structures of luminescent isomeric acetylnaphtholates of boron difluoride are investigated. Full X-ray structural analysis is done at 293 K. Coordinated of atoms, bond angles, bond lengths, interatomic distances are determined. Results of comparative evaluations of the isomers are represented [ru

  7. Radiobiology of boron neutron capture therapy

    International Nuclear Information System (INIS)

    Bond, V.P.

    1986-01-01

    The author addresses the question of single session versus protracted therapy in the application of boron neutron therapy to tumors. As background he discusses the reasoning behind the current use of fractionated therapy with conventional low-LET radiations and difference which may obtain for neutron therapy. Several aspects of dose rates and dose levels are then addressed

  8. Elements of abstract harmonic analysis

    CERN Document Server

    Bachman, George

    2013-01-01

    Elements of Abstract Harmonic Analysis provides an introduction to the fundamental concepts and basic theorems of abstract harmonic analysis. In order to give a reasonably complete and self-contained introduction to the subject, most of the proofs have been presented in great detail thereby making the development understandable to a very wide audience. Exercises have been supplied at the end of each chapter. Some of these are meant to extend the theory slightly while others should serve to test the reader's understanding of the material presented. The first chapter and part of the second give

  9. BCM6: New Generation of Boron Meter

    International Nuclear Information System (INIS)

    Pirat, P.

    2010-01-01

    Full text of publication follows: Rolls-Royce has developed a new generation of boron meter, based on more than 30 years of experience. The Rolls-Royce BCM6 boron meter provides Nuclear Power Plant (NPP) operators with the boron concentration of the primary circuit. The meter provides continuous and safe measurements with no manual sampling and no human contact. In this paper, technical features, advantages and customer benefits of the use of the new generation of Rolls-Royce BCM6 boron meter will be detailed. Values and associated alarms are provides over different media: 4-20 mA outputs, relays, displays in the main control room and in the chemical lab, and digital links. A special alarm avoids unexpected homogeneous dilution of the primary circuit, which is a critical operational parameter. The Rolls-Royce BCM6 boron meter is fully configurable over a set of parameters allowing adaptation to customer needs. It has a differential capability, thus eliminating neutronic noise and keeping measurements accurate, even in the case of fuel clad rupture. Measurements are accurate, reliable, and have a quick response time. Equipment meets state-of-the-art qualification requests. Designed in 2008, the BCM6 boron meter is the newest equipment of Rolls-Royce boron meters product line. It has been chosen to equip the French EPR NPP and complies with the state-of-the-art of the technology. Rolls-Royce has more than 30 years of experience in Instrumentation and Controls with more than 75 NPP units operating worldwide. All of this experience return has been put in this new generation of equipment to provide the customer with the best operation. About Rolls-Royce Rolls-Royce is a global business providing integrated power systems for use on land, at sea and in the air. The Group has a balanced business portfolio with leading market positions. Rolls-Royce has a broad range of civil nuclear expertise, including work related to licensing and safety reviews, engineering design

  10. Large Eddy Simulation for an inherent boron dilution transient

    International Nuclear Information System (INIS)

    Jayaraju, S.T.; Sathiah, P.; Komen, E.M.J.; Baglietto, E.

    2013-01-01

    Highlights: • Large Eddy Simulation is performed for a transient boron dilution scenario in the scaled experimental facility of ROCOM. • Fully conformal polyhedral grid of 14 million is created to capture all details of the domain. • Systematic multi-step validation methodology is followed to assess the accuracy of LES model. • For the presently simulated BDT scenario, the LES results lend support to its reliability in consistently predicting the slug transport in the RPV. -- Abstract: The present paper focuses on the validation and applicability of large eddy simulation (LES) to analyze the transport and mixing in the reactor pressure vessel (RPV) during an inherent boron dilution transient (BDT) scenario. Extensive validation data comes from relevant integral tests performed in the scaled ROCOM experimental facility. The modeling of sub-grid-scales is based on the WALE model. A fully conformal polyhedral grid of about 15 million cells is constructed to capture all details in the domain, including the complex structures of the lower-plenum. Detailed qualitative and quantitative validations are performed by following a systematic multi-step validation methodology. Qualitative comparisons to the experimental data in the cold legs, downcomer and the core inlet showed good predictions by the LES model. Minor deviations seen in the quantitative comparisons are rigorously quantified. A key parameter which is affecting the core neutron kinetics response is the value of highest deborated slug concentration that occurs at the core inlet during the transient. Detailed analyses are made at the core inlet to evaluate not only the value of the maximum slug concentration, but also the location and the time at which it occurs during the transient. The relative differences between the ensemble averaged experimental data and CFD predictions were within the range of relative differences seen within 10 different experimental realizations. For the studied scenario, the

  11. Thermal conductivity of polymer composites with oriented boron nitride

    International Nuclear Information System (INIS)

    Ahn, Hong Jun; Eoh, Young Jun; Park, Sung Dae; Kim, Eung Soo

    2014-01-01

    Highlights: • Thermal conductivity depended on the orientation of BN in the polymer matrices. • Hexagonal boron nitride (BN) particles were treated by C 27 H 27 N 3 O 2 and C 14 H 6 O 8 . • Amphiphilic-agent-treated BN particles are more easily oriented in the composite. • BN/PVA composites with C 14 H 6 O 8 -treated BN showed the highest thermal conductivity. • Thermal conductivity of the composites was compared with several theoretical models. - Abstract: Thermal conductivity of boron nitride (BN) with polyvinyl alcohol (PVA) and/or polyvinyl butyral (PVB) was investigated as a function of the degree of BN orientation, the numbers of hydroxyl groups in the polymer matrices and the amphiphilic agents used. The composites with in-plane orientation of BN showed a higher thermal conductivity than the composites with out-of-plane orientation of BN due to the increase of thermal pathway. For a given BN content, the composites with in-plane orientation of BN/PVA showed higher thermal conductivity than the composites with in-plane orientation of BN/PVB. This result could be attributed to the improved degree of orientation of BN, caused by a larger number of hydroxyl groups being present. Those treated with C 14 H 6 O 8 amphiphilic agent demonstrated a higher thermal conductivity than those treated by C 27 H 27 N 3 O 2 . The measured thermal conductivity of the composites was compared with that predicted by the several theoretical models

  12. Boron cross-linked graphene oxide/polyvinyl alcohol nanocomposite gel electrolyte for flexible solid-state electric double layer capacitor with high performance

    International Nuclear Information System (INIS)

    Huang, Yi-Fu; Wu, Peng-Fei; Zhang, Ming-Qiu; Ruan, Wen-Hong; Giannelis, Emmanuel P.

    2014-01-01

    Highlights: • Gel electrolyte is prepared and used in electric double layer capacitor. • Insertion of boron crosslinks into GO agglomerates opens channels for ion migration. • Solid supercapacitors show excellent specific capacitance and cycle stability. • Nanocomposite electrolyte shows better thermal stability and mechanical properties. - Abstract: A new family of boron cross-linked graphene oxide/polyvinyl alcohol (GO-B-PVA) nanocomposite gels is prepared by freeze-thaw/boron cross-linking method. Then the gel electrolytes saturated with KOH solution are assembled into electric double layer capacitors (EDLCs). Structure, thermal and mechanical properties of GO-B-PVA are explored. The electrochemical properties of EDLCs using GO-B-PVA/KOH are investigated, and compared with those using GO-PVA/KOH gel or KOH solution electrolyte. FTIR shows that boron cross-links are introduced into GO-PVA, while the boronic structure inserted into agglomerated GO sheets is demonstrated by DMA analysis. The synergy effect of the GO and the boron crosslinking benefits for ionic conductivity due to unblocking ion channels, and for improvement of thermal stability and mechanical properties of the electrolytes. Higher specific capacitance and better cycle stability of EDLCs are obtained by using the GO-B-PVA/KOH electrolyte, especially the one at higher GO content. The nanocomposite gel electrolytes with excellent electrochemical properties and solid-like character are candidates for the industrial application in high-performance flexible solid-state EDLCs

  13. Biocards and Level of Abstraction

    DEFF Research Database (Denmark)

    Lenau, Torben Anker; Keshwani, Sonal; Chakrabarti, Amaresh

    2015-01-01

    Biocards are formal descriptions of biological phenomena and their underlying functional principles. They are used in bioinspired design to document search results and to communicate the findings for use in the further design process. The present study explored the effect of abstraction level used...

  14. Teaching abstraction in introductory courses

    NARCIS (Netherlands)

    Koppelman, Herman; van Dijk, Betsy

    Abstraction is viewed as a key concept in computer science. It is not only an important concept but also one that is difficult to master. This paper focuses on the problems that novices experience when they first encounter this concept. Three assignments from introductory courses are analyzed, to

  15. Abstract Interpretation of Mobile Ambients

    DEFF Research Database (Denmark)

    Hansen, René Rydhof; Jensen, J. G.; Nielson, Flemming

    1999-01-01

    We demonstrate that abstract interpretation is useful for analysing calculi of computation such as the ambient calculus (which is based on the p-calculus); more importantly, we show that the entire development can be expressed in a constraint-based formalism that is becoming exceedingly popular...

  16. IRAP 2006, Book of Abstracts

    International Nuclear Information System (INIS)

    2006-01-01

    This publications related with Hacettepe University, Turkish Atomic Energy Authority, The Scientific and Technological Research Council of Turkey, International Atomic Energy Agency, CEA-Saclay, CEA-Saclay Drecam, ANKAmall Shopping Center and Ion Beam Applications Industrial that was held in Antalya, Turkey, 23-28 September 2006. A separate abstract was prepared for each paper

  17. IRAP 2006, Book of Abstracts

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2006-07-01

    This publications related with Hacettepe University, Turkish Atomic Energy Authority, The Scientific and Technological Research Council of Turkey, International Atomic Energy Agency, CEA-Saclay, CEA-Saclay Drecam, ANKAmall Shopping Center and Ion Beam Applications Industrial that was held in Antalya, Turkey, 23-28 September 2006. A separate abstract was prepared for each paper.

  18. The Complexity of Abstract Machines

    Directory of Open Access Journals (Sweden)

    Beniamino Accattoli

    2017-01-01

    Full Text Available The lambda-calculus is a peculiar computational model whose definition does not come with a notion of machine. Unsurprisingly, implementations of the lambda-calculus have been studied for decades. Abstract machines are implementations schema for fixed evaluation strategies that are a compromise between theory and practice: they are concrete enough to provide a notion of machine and abstract enough to avoid the many intricacies of actual implementations. There is an extensive literature about abstract machines for the lambda-calculus, and yet—quite mysteriously—the efficiency of these machines with respect to the strategy that they implement has almost never been studied. This paper provides an unusual introduction to abstract machines, based on the complexity of their overhead with respect to the length of the implemented strategies. It is conceived to be a tutorial, focusing on the case study of implementing the weak head (call-by-name strategy, and yet it is an original re-elaboration of known results. Moreover, some of the observation contained here never appeared in print before.

  19. Abstract Interpretation Using Attribute Grammar

    DEFF Research Database (Denmark)

    Rosendahl, Mads

    1990-01-01

    This paper deals with the correctness proofs of attribute grammars using methods from abstract interpretation. The technique will be described by defining a live-variable analysis for a small flow-chart language and proving it correct with respect to a continuation style semantics. The proof...

  20. Rabies in the Americas

    Science.gov (United States)

    Rabies in the Americas Search this site Welcome Previous Meetings Steering Committee Contact Sitemap Welcome The Rabies in the Americas (RITA) meeting is an annual event that has been held since 1990 managers of rabies programs, wildlife biologists, laboratory personnel and other people interested in

  1. World review: Latin America

    International Nuclear Information System (INIS)

    Anon.

    2000-01-01

    The article gives information on contracts announced (and to whom) throughout Latin America in all aspects of the petroleum, natural gas and petrochemicals industries. Countries specifically mentioned are Argentina, Brazil, Chile, Mexico, Trinidad and Venezuela. The future for the oil industry in Latin America is viewed as 'highly prospective'

  2. America in the Eyes of America Watchers:

    DEFF Research Database (Denmark)

    Feng, Huiyun; He, Kai

    2015-01-01

    Based on an original survey conducted in the summer of 2012 in Beijing, we examine how China's America watchers—IR scholars who work on US-China relations—have viewed China's power status in the international system, US-China relations and some specific US policies in Asia. Our survey shows that ...

  3. Raman spectroscopy of boron-doped single-layer graphene.

    Science.gov (United States)

    Kim, Yoong Ahm; Fujisawa, Kazunori; Muramatsu, Hiroyuki; Hayashi, Takuya; Endo, Morinobu; Fujimori, Toshihiko; Kaneko, Katsumi; Terrones, Mauricio; Behrends, Jan; Eckmann, Axel; Casiraghi, Cinzia; Novoselov, Kostya S; Saito, Riichiro; Dresselhaus, Mildred S

    2012-07-24

    The introduction of foreign atoms, such as nitrogen, into the hexagonal network of an sp(2)-hybridized carbon atom monolayer has been demonstrated and constitutes an effective tool for tailoring the intrinsic properties of graphene. Here, we report that boron atoms can be efficiently substituted for carbon in graphene. Single-layer graphene substitutionally doped with boron was prepared by the mechanical exfoliation of boron-doped graphite. X-ray photoelectron spectroscopy demonstrated that the amount of substitutional boron in graphite was ~0.22 atom %. Raman spectroscopy demonstrated that the boron atoms were spaced 4.76 nm apart in single-layer graphene. The 7-fold higher intensity of the D-band when compared to the G-band was explained by the elastically scattered photoexcited electrons by boron atoms before emitting a phonon. The frequency of the G-band in single-layer substitutionally boron-doped graphene was unchanged, which could be explained by the p-type boron doping (stiffening) counteracting the tensile strain effect of the larger carbon-boron bond length (softening). Boron-doped graphene appears to be a useful tool for engineering the physical and chemical properties of graphene.

  4. Laser-induced photochemical enrichment of boron isotopes

    International Nuclear Information System (INIS)

    Freund, S.M.; Ritter, J.J.

    1976-01-01

    A boron trichloride starting material containing both boron-10 isotopes and boron-11 isotopes is selectively enriched in one or the other of these isotopes by a laser-induced photochemical method involving the reaction of laser-excited boron trichloride with either H 2 S or D 2 S. The method is carried out by subjecting a low pressure gaseous mixture of boron trichloride starting material and the sulfide to infrared radiation from a carbon dioxide TE laser. The wave length of the radiation is selected so as to selectively excite one or the other of boron-10 BCl 3 molecules or boron-11 BCl 3 molecules, thereby making them preferentially more reactive with the sulfide. The laser-induced reaction produces both a boron-containing solid phase reaction product and a gaseous phase containing mostly unreacted BCl 3 and small amounts of sulfhydroboranes. Pure boron trichloride selectively enriched in one of the isotopes is recovered as the primary product of the method from the gaseous phase by a multi-step recovery procedure. Pure boron trichloride enriched in the other isotope is recovered as a secondary product of the method by the subsequent chlorination of the solid phase reaction product followed by separation of BCl 3 from the mixture of gaseous products resulting from the chlorination

  5. Higher boron rejection with a new TFC forward osmosis membrane

    KAUST Repository

    Valladares Linares, Rodrigo; Li, Zhenyu; Sarp, Sarper; Park, Y. G.; Amy, Gary L.; Vrouwenvelder, Johannes S.

    2014-01-01

    Due to the stringent limits for boron in drinking and irrigation water, water treatment facilities have to incur additional treatment to remove boron down to a safe concentration. Forward osmosis (FO) is a membrane technology that may reduce the energy required to remove boron present in seawater. In direct FO desalination hybrid systems, fresh water is recovered from seawater using a recoverable draw solution, FO membranes are expected to show high boron rejection. This study focuses on determining the boron rejection capabilities of a new generation thin-film composite (TFC) FO membrane compared to a first generation cellulose triacetate (CTA) FO membrane. The effects of water permeate flux, membrane structure, draw solute charge, and reverse solute flux on boron rejection were determined. For TFC and CTA FO membranes, experiments showed that when similar operating conditions are applied (e.g. membrane type and draw solute type) boron rejection decreases with increase in permeate flux. Reverse draw solute flux and membrane fouling have no significant impact on boron rejection. Compared to the first generation CTA FO membrane operated at the same conditions, the TFC FO membrane showed a 40% higher boron rejection capability and a 20% higher water flux. This demonstrates the potential for boron removal for new generation TFC FO membranes. © 2014 © 2014 Balaban Desalination Publications. All rights reserved.

  6. ISOBORDAT: An Online Data Base on Boron Isotopes

    Energy Technology Data Exchange (ETDEWEB)

    Pennisi, M.; Adorni-Braccesi, A.; Andreani, D.; Gori, L.; Gonfiantini, R. [Istituto di Geoscienze e Georisorse, CNR, Pisa (Italy); Sciuto, P. F. [Servizio Geologico, Sismico e dei Suoli, D.G. Ambiente e Difesa del Suolo e della Costa, Regione Emilia Romagna, Bologna (Italy)

    2013-07-15

    From 1986, boron isotope data in natural substances increased sharply in scientific publications. Analytical difficulties derived from complex geochemical matrices have been faced and interlaboratory calibrations reported in the boron literature. Boron isotopes are nowdays applied to investigate boron origin and migration in natural waters, sources of boron contamination, water-rock interactions and also contribute to water resource management. This is especially important in those areas where boron content exceeds the local regulations for drinking water supply and boron sources need to be identified. ISOBORDAT, an interactive database on boron isotope composition and content in natural waters is presented to the wider community of boron isotope users. The database's structure, scope and applications are reported, along with a discussion on {delta}{sup 11}B values obtained in Italian waters. In the database boron data are structured in the following categories: rainwater, rivers, lakes, groundwater and potential contaminants. New categories (medium and high enthalpy fluids from volcanic and geothermal areas) are anticipated. ISOBORDAT aims to be as interactive as possible and will be developed taking into account information and suggestions received. The database is continually undergoing revision to keep pace with continuous data publication. Indications of data that are missing at present are greatly appreciated. (author)

  7. Synthesis and characterization of ammonium phosphate fertilizers with boron

    Directory of Open Access Journals (Sweden)

    ANGELA MAGDA

    2010-07-01

    Full Text Available The concentration of boron, an essential micronutrient for plants, presents a narrow range between deficiency and toxicity. In order to provide the boron requirement for plants, and to avoid toxicity problems, boron compounds are mixed with basic fertilizers. Sodium borate pentahydrate was used as a boron source. Ammonium orthophosphates fertilizers with boron were prepared by neutralizing phosphoric acid with ammonia and addition of variable amounts of sodium tetraborate pentahydrate to the reaction mixture at a NH3:H3PO4 molar ratio of 1.5. The fertilizers obtained with boron contents ranging from 0.05 to 1 % (w/w were fully characterized by chemical analysis, thermal analysis, X-ray diffraction and infrared spectrophotometry. The studies showed that up to 500 °C, regardless of the boron content, no significant changes concerning thermal stability and nutritional properties occurred. Above 500 °C, an increase of thermal stability with an increase of the boron content was observed. X-Ray diffraction of a heat-treated sample containing 5 % (w/w boron indicated the appearance of boron orthophosphate, BPO4, as a new crystalline phase, and the disappearance of the previous structures above 500 °C, which explains the increase in thermal stability.

  8. Higher boron rejection with a new TFC forward osmosis membrane

    KAUST Repository

    Valladares Linares, Rodrigo

    2014-07-17

    Due to the stringent limits for boron in drinking and irrigation water, water treatment facilities have to incur additional treatment to remove boron down to a safe concentration. Forward osmosis (FO) is a membrane technology that may reduce the energy required to remove boron present in seawater. In direct FO desalination hybrid systems, fresh water is recovered from seawater using a recoverable draw solution, FO membranes are expected to show high boron rejection. This study focuses on determining the boron rejection capabilities of a new generation thin-film composite (TFC) FO membrane compared to a first generation cellulose triacetate (CTA) FO membrane. The effects of water permeate flux, membrane structure, draw solute charge, and reverse solute flux on boron rejection were determined. For TFC and CTA FO membranes, experiments showed that when similar operating conditions are applied (e.g. membrane type and draw solute type) boron rejection decreases with increase in permeate flux. Reverse draw solute flux and membrane fouling have no significant impact on boron rejection. Compared to the first generation CTA FO membrane operated at the same conditions, the TFC FO membrane showed a 40% higher boron rejection capability and a 20% higher water flux. This demonstrates the potential for boron removal for new generation TFC FO membranes. © 2014 © 2014 Balaban Desalination Publications. All rights reserved.

  9. Roughness-based monitoring of transparency and conductivity in boron-doped ZnO thin films prepared by spray pyrolysis

    International Nuclear Information System (INIS)

    Gaikwad, Rajendra S.; Bhande, Sambhaji S.; Mane, Rajaram S.; Pawar, Bhagwat N.; Gaikwad, Sanjay L.; Han, Sung-Hwan; Joo, Oh-Shim

    2012-01-01

    Graphical abstract: Display Omitted Highlights: ► We report surface roughness dependent transparency and conductivity in ZnO films. ► The surface roughness with respected to boron doping concentrations is studied. ► Boron doped and pristine Zinc oxide thin films have showed ≥95% transmittance. ► Increased carrier concentration of 9.21 × 10 21 cm −3 revealed from Hall measurement. -- Abstract: Sprayed polycrystalline ZnO and boron-doped ZnO thin films composed of spherical grains of 25–32 nm in diameters are used in roughness measurement and further correlated with the transparency and the conductivity characteristics. The surface roughness is increased up to Zn 0.98 B 0.02 O and then declined at higher boron concentrations. The sprayed ZnO films revealed ≥95% transmittance in the visible wavelength range, 1.956 × 10 −4 Ω cm electrical resistivity, 46 cm 2 /V s Hall mobility and 9.21 × 10 21 cm −3 charge carrier concentration. The X-ray photoelectron spectroscopy study has confirmed 0.15 eV binding energy change for Zn 2p 3/2 when 2 at% boron content is mixed without altering electro-optical properties substantially. Finally, using soft modeling importance of these textured ZnO over non-textured films for enhancing the solar cells performance is explored.

  10. America's Children and the Environment

    Science.gov (United States)

    ... Labs and Research Centers America's Children and the Environment (ACE) Contact Us Share ACE presents key information ... of updates to ACE . America's Children and the Environment (ACE) America's Children and the Environment (ACE) is ...

  11. XPS analysis for cubic boron nitride crystal synthesized under high pressure and high temperature using Li3N as catalysis

    International Nuclear Information System (INIS)

    Guo, Xiaofei; Xu, Bin; Zhang, Wen; Cai, Zhichao; Wen, Zhenxing

    2014-01-01

    Highlights: • The cBN was synthesized by Li 3 N as catalyst under high pressure and high temperature (HPHT). • The film coated on the as-grown cBN crystals was studied by XPS. • The electronic structure variation in the film was investigated. • The growth mechanism of cubic boron nitride crystal was analyzed briefly. - Abstract: Cubic boron nitride (cBN) single crystals are synthesized with lithium nitride (Li3N) as catalyst under high pressure and high temperature. The variation of electronic structures from boron nitride of different layers in coating film on the cBN single crystal has been investigated by X-ray photoelectron spectroscopy. Combining the atomic concentration analysis, it was shown that from the film/cBN crystal interface to the inner, the sp 2 fractions are decreasing, and the sp 3 fractions are increasing in the film at the same time. Moreover, by transmission electron microscopy, a lot of cBN microparticles are found in the interface. For there is no Li 3 N in the film, it is possible that Li 3 N first reacts with hexagonal boron nitride to produce Li 3 BN 2 during cBN crystals synthesis under high pressure and high temperature (HPHT). Boron and nitrogen atoms, required for cBN crystals growth, could come from the direct conversion from hexagonal boron nitride with the catalysis of Li 3 BN 2 under high pressure and high temperature, but not directly from the decomposition of Li 3 BN 2

  12. Learning abstract algebra with ISETL

    CERN Document Server

    Dubinsky, Ed

    1994-01-01

    Most students in abstract algebra classes have great difficulty making sense of what the instructor is saying. Moreover, this seems to remain true almost independently of the quality of the lecture. This book is based on the constructivist belief that, before students can make sense of any presentation of abstract mathematics, they need to be engaged in mental activities which will establish an experiential base for any future verbal explanation. No less, they need to have the opportunity to reflect on their activities. This approach is based on extensive theoretical and empirical studies as well as on the substantial experience of the authors in teaching astract algebra. The main source of activities in this course is computer constructions, specifically, small programs written in the mathlike programming language ISETL; the main tool for reflections is work in teams of 2-4 students, where the activities are discussed and debated. Because of the similarity of ISETL expressions to standard written mathematics...

  13. Abstract Cauchy problems three approaches

    CERN Document Server

    Melnikova, Irina V

    2001-01-01

    Although the theory of well-posed Cauchy problems is reasonably understood, ill-posed problems-involved in a numerous mathematical models in physics, engineering, and finance- can be approached in a variety of ways. Historically, there have been three major strategies for dealing with such problems: semigroup, abstract distribution, and regularization methods. Semigroup and distribution methods restore well-posedness, in a modern weak sense. Regularization methods provide approximate solutions to ill-posed problems. Although these approaches were extensively developed over the last decades by many researchers, nowhere could one find a comprehensive treatment of all three approaches.Abstract Cauchy Problems: Three Approaches provides an innovative, self-contained account of these methods and, furthermore, demonstrates and studies some of the profound connections between them. The authors discuss the application of different methods not only to the Cauchy problem that is not well-posed in the classical sense, b...

  14. ESGAR 2007. Book of abstracts

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2007-06-15

    The book includes the abstracts of all contributions presented during ESGAR (European Society of Gastrointestinal and Abdominal Radiology) 2007. The contributions of the symposium and the scientific sessions cover the following topics: abdominal MRI; interactive liver diagnosis; rectal cancer; liver metastases; pancreas: technical advances, lesion characterisation and staging; hepatic interventions; upper GI tract: multimodality evaluation; Crohn's disease evaluation; focal liver lesions: multimodality evaluation; CTC-computer aided diagnosis; bile ducts: imaging and intervention; GI tract: imaging and intervention; small bowel and appendix: cross-sectional imaging; CT and MR colonography; trauma and acute abdominal conditions: imaging and intervention; vascular and diffuse liver disease; liver contrast enhanced US. The second part covers the abstract of 248 presentations.

  15. Cryogenic foam insulation: Abstracted publications

    Science.gov (United States)

    Williamson, F. R.

    1977-01-01

    A group of documents were chosen and abstracted which contain information on the properties of foam materials and on the use of foams as thermal insulation at cryogenic temperatures. The properties include thermal properties, mechanical properties, and compatibility properties with oxygen and other cryogenic fluids. Uses of foams include applications as thermal insulation for spacecraft propellant tanks, and for liquefied natural gas storage tanks and pipelines.

  16. The abstract unconscious in painting

    OpenAIRE

    Parker, David

    2009-01-01

    The Abstract Unconscious in Painting addresses painting as experiential process, critically examining the psychological factors involved in the formation of imagery as it emerges through imaginative responses to the process of mark making and the structuring of space and form. The paper sets this process in relation to theoretical material drawn from Jungian and Post Jungian Psychology ( Avens, 1980; Hillman, 1975) the arts ( Gombrich, 1960; Kuspit, 2000; McKeever, 2005; Worringer, 1908) and ...

  17. Abstract specialization and its applications

    OpenAIRE

    Puebla Sánchez, Alvaro Germán; Hermenegildo, Manuel V.

    2003-01-01

    The aim of program specialization is to optimize programs by exploiting certain knowledge about the context in which the program will execute. There exist many program manipulation techniques which allow specializing the program in different ways. Among them, one of the best known techniques is partial evaluation, often referred to simply as program specialization, which optimizes programs by specializing them for (partially) known input data. In this work we describe abstract specia...

  18. Boron autoradiography method applied to the study of steels

    International Nuclear Information System (INIS)

    Gugelmeier, R.; Barcelo, G.N.; Boado, J.H.; Fernandez, C.

    1986-01-01

    The boron state, contained in the steel microestructure, is determined. The autoradiography by neutrons is used, permiting to obtain boron distribution images by means of additional information which is difficult to acquire by other methods. The application of the method is described, based on the neutronic irradiation of a polished steel sample, over which a celulose nitrate sheet or other appropriate material is fixed to constitute the detector. The particles generated by the neutron-boron interaction affect the detector sheet, which is subsequently revealed with a chemical treatment and can be observed at the optical microscope. In the case of materials used for the construction of nuclear reactors, special attention must be given to the presence of boron, since owing to the exceptionaly high capacity of neutron absorption, lowest quantities of boron acquire importance. The adaption of the method to metallurgical problems allows the obtainment of a correlation between the boron distribution images and the material's microstructure. (M.E.L.) [es

  19. Evolution of anisotropy in bcc Fe distorted by interstitial boron

    Science.gov (United States)

    Gölden, Dominik; Zhang, Hongbin; Radulov, Iliya; Dirba, Imants; Komissinskiy, Philipp; Hildebrandt, Erwin; Alff, Lambert

    2018-01-01

    The evolution of magnetic anisotropy in bcc Fe as a function of interstitial boron atoms was investigated in thin films grown by molecular beam epitaxy. The thermodynamic nonequilibrium conditions during film growth allowed one to stabilize an interstitial boron content of about 14 at .% accompanied by lattice tetragonalization. The c /a ratio scaled linearly with the boron content up to a maximum value of 1.05 at 300 °C substrate growth temperature, with a room-temperature magnetization of. In contrast to nitrogen interstitials, the magnetic easy axis remained in-plane with an anisotropy of approximately -5.1 ×106erg /cm3 . Density functional theory calculations using the measured lattice parameters confirm this value and show that boron local ordering indeed favors in-plane magnetization. Given the increased temperature stability of boron interstitials as compared to nitrogen interstitials, this study will help to find possible ways to manipulate boron interstitials into a more favorable local order.

  20. Synthesis of Boron Nano wires, Nano tubes, and Nano sheets

    International Nuclear Information System (INIS)

    Patel, R.B.; Chou, T.; Iqbal, Z.

    2014-01-01

    The synthesis of boron nano wires, nano tubes, and nano sheets using a thermal vapor deposition process is reported. This work confirms previous research and provides a new method capable of synthesizing boron nano materials. The materials were made by using various combinations of MgB 2 , Mg(BH 4 ) 2 , MCM-41, NiB, and Fe wire. Unlike previously reported methods, a nanoparticle catalyst and a silicate substrate are not required for synthesis. Two types of boron nano wires, boron nano tubes, and boron nano sheets were made. Their morphology and chemical composition were determined through the use of scanning electron microscopy, transmission electron microscopy, and electron energy loss spectroscopy. These boron-based materials have potential for electronic and hydrogen storage applications.

  1. Influence of dopants, particularly carbon, on β-rhombohedral boron

    Science.gov (United States)

    Werheit, H.; Flachbart, K.; Pristáš, G.; Lotnyk, D.; Filipov, V.; Kuhlmann, U.; Shitsevalova, N.; Lundström, T.

    2017-09-01

    Due to the high affinity of carbon to boron, the preparation of carbon-free boron is problematic. Even high-purity (6 N) β-rhombohedral boron contains 30-60 ppm of C. Hence, carbon affects the boron physical properties published so far more or less significantly. We studied well-defined carbon-doped boron samples based on pure starting material carefully annealed with up to about 1% C, thus assuring homogeneity. We present and discuss their electrical conductivity, optical absorption, luminescence and phonon spectra. Earlier attempts of other authors to determine the conductivity of C-doped boron are revised. Our results allow estimating the effects of oxygen and iron doping on the electrical conductivity using results taken from literature. Discontinuities at low T impair the electronic properties.

  2. The influence of metal Mg on micro-morphology and crystallinity of spherical hexagonal boron nitride

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Ning, E-mail: zhangning5832@163.com; Liu, Huan; Kan, Hongmin; Wang, Xiaoyang; Long, Haibo; Zhou, Yonghui

    2015-08-15

    Highlights: • The action mechanism of Mg to the synthesis of spherical BN was explored. • The influence of Mg content on the crystallinity of h-BN powders was studied. • Even if not added any template, the spherical h-BN could be prepared. - Abstract: This search used the boric acid and borax as a source of boron, urea as a nitrogen source, Mg as metal catalyst, and thus prepared different micro-morphology and crystallinity hexagonal boron nitride powders under a flowing ammonia atmosphere at a nitriding temperature of 750 °C. The effect of Mg content on the crystallinity and micro-morphology of hexagonal boron nitride powders was studied, and the Mg action mechanism was explored. Without the added surfactant, the graphitization index (GI) was 6.87, and the diameter of the spherical h-BN was bigger. When the added Mg were 0.1 g, 0.3 g, 0.5 g and 0.7 g, the (GI) decreased to 6.04, 5.67, 4.62 and 4.84, respectively. When the Mg content was higher (0.9 g), GI value increased rapidly, and the crystallinity became bad. When the Mg content was 0.5 g, the dispersion of h-BN powders was at its optimum and refinement apparently, and the crystallinity at its highest.

  3. Control of core structure in MgB{sub 2} wire through tailoring boron powder

    Energy Technology Data Exchange (ETDEWEB)

    Maeda, Minoru, E-mail: maeda.minoru70@nihon-u.ac.jp [Department of Physics, College of Science and Technology, Nihon University, 1-8-14 Kanda-Surugadai, Chiyoda-ku, Tokyo 101-8308 (Japan); Uchiyama, Daisuke [Department of Physics, College of Science and Technology, Nihon University, 1-8-14 Kanda-Surugadai, Chiyoda-ku, Tokyo 101-8308 (Japan); Hossain, Md Shahriar Al; Ma, Zongqing [Institute for Superconducting and Electronic Materials, University of Wollongong, North Wollongong, New South Wales 2500 (Australia); Shahabuddin, Mohammed [Department of Physics and Astronomy, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451 (Saudi Arabia); Kim, Jung Ho, E-mail: jhk@uow.edu.au [Institute for Superconducting and Electronic Materials, University of Wollongong, North Wollongong, New South Wales 2500 (Australia)

    2015-07-05

    Highlights: • The typical void structure in the wire is obtained by using large-sized B powder. • In contrast, void alignment can be achieved by using fine B powder. • The sintering at lower temperatures improves the critical current density in fields. - Abstract: A common fabrication process for MgB{sub 2} wire, namely, the in situ powder-in-tube process, forms numerous voids within the wire core, and void formation cannot be completely avoided. The orientation is, however, known to be aligned more or less along the current-flow direction when ductile coarse magnesium powder is used as a precursor, and further tailoring approaches could open up the way to improving the transport critical current density. Herein, we have used boron powders with different particle sizes, in combination with the coarse magnesium powder, and evaluated their size effects on the phase composition, microstructure, and transport properties. A mixture of the coarse magnesium powder with large-sized boron powder in the wire core, after cold working and sintering, forms a granular morphology. In contrast, an aligned core appears during the reduction process for wire which is prepared by using fine boron powder. The sintering process, especially at a low temperature, where magnesium evaporation hardly occurs, yields an aligned structure, mainly consisting of MgB{sub 2} phase, along the wire direction. These findings demonstrate that the initial size of the starting materials is critical for the tailored structure.

  4. Thermal conductivity enhancement of paraffin by adding boron nitride nanostructures: A molecular dynamics study

    International Nuclear Information System (INIS)

    Lin, Changpeng; Rao, Zhonghao

    2017-01-01

    Highlights: • Different contributions to thermal conductivity are obtained. • Thermal conductivity of paraffin could be improved by boron nitride. • Crystallization effect from boron nitride was the key factor. • Paraffin nanocomposite is the desirable candidate for thermal energy storage. - Abstract: While paraffin is widely used in thermal energy storage today, its low thermal conductivity has become a bottleneck for the further applications. Here, we construct two kinds of paraffin-based phase change material nanocomposites through introducing boron nitride (BN) nanostructures into n-eicosane to enhance the thermal conductivity. Molecular dynamics (MD) simulation was adopted to estimate their thermal conductivities and related thermal properties. The results indicate that, after adding BN nanostructures, the latent heat of composites is reduced compared with the pure paraffin and they both show a glass-like thermal conductivity which increases as the temperature rises. This happens because the increasing temperature leads to gradually smaller inconsistency in vibrational density of state along three directions and increasingly significant overlaps among them. Furthermore, by decomposing the thermal conductivity, it is found that the major contribution to the overall thermal conductivity comes from BN nanostructures, while the contribution of n-eicosane is insignificant. Though the thermal conductivity from n-eicosane term is small, it has been improved greatly compared with amorphous state of n-eicosane, mainly due to the crystallization effects from BN nanostructures. This work will provide microscopic views and insights into the thermal mechanism of paraffin and offer effective guidances to enhance the thermal conductivity.

  5. Pulverization of boron element and proportions of boron carbide in boron; Broyage de bore element et dosage de carbure de bore dans le bore

    Energy Technology Data Exchange (ETDEWEB)

    Lang, F M; Finck, C [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1956-07-01

    It is possible to reduce boron element into fine powder by means of a mortar and pestle made of sintered boron carbide, the ratio of boron carbide introduced being less than one per cent. Boron element at our disposal is made of sharp edged, dark brown, little grains of average size greater than 5 {mu}. Grain sizes smaller than 1{mu} are required for applying thin layers of such boron. (author) [French] Il est possible de pulveriser finement du bore element au moyen de mortier et pilon en carbure de bore fritte, le taux de carbure de bore introduit etant inferieur a 1 pour cent. Le bore element dont nous disposons est constitue de petits grains brun fonce, a aretes vives, de dimension moyenne superieure a 5 {mu}. L'application de ce bore en couches minces demande des grains de dimensions inferieures a 1 {mu}. (aute0008.

  6. Characterization of boron doped nanocrystalline diamonds

    International Nuclear Information System (INIS)

    Peterlevitz, A C; Manne, G M; Sampaio, M A; Quispe, J C R; Pasquetto, M P; Iannini, R F; Ceragioli, H J; Baranauskas, V

    2008-01-01

    Nanostructured diamond doped with boron was prepared using a hot-filament assisted chemical vapour deposition system fed with an ethyl alcohol, hydrogen and argon mixture. The reduction of the diamond grains to the nanoscale was produced by secondary nucleation and defects induced by argon and boron atoms via surface reactions during chemical vapour deposition. Raman measurements show that the samples are nanodiamonds embedded in a matrix of graphite and disordered carbon grains, while morphological investigations using field electron scanning microscopy show that the size of the grains ranges from 20 to 100 nm. The lowest threshold fields achieved were in the 1.6 to 2.4 V/μm range

  7. Boron Nitride Nanotube: Synthesis and Applications

    Science.gov (United States)

    Tiano, Amanda L.; Park, Cheol; Lee, Joseph W.; Luong, Hoa H.; Gibbons, Luke J.; Chu, Sang-Hyon; Applin, Samantha I.; Gnoffo, Peter; Lowther, Sharon; Kim, Hyun Jung; hide

    2014-01-01

    Scientists have predicted that carbon's immediate neighbors on the periodic chart, boron and nitrogen, may also form perfect nanotubes, since the advent of carbon nanotubes (CNTs) in 1991. First proposed then synthesized by researchers at UC Berkeley in the mid 1990's, the boron nitride nanotube (BNNT) has proven very difficult to make until now. Herein we provide an update on a catalyst-free method for synthesizing highly crystalline, small diameter BNNTs with a high aspect ratio using a high power laser under a high pressure and high temperature environment first discovered jointly by NASA/NIA JSA. Progress in purification methods, dispersion studies, BNNT mat and composite formation, and modeling and diagnostics will also be presented. The white BNNTs offer extraordinary properties including neutron radiation shielding, piezoelectricity, thermal oxidative stability (> 800 C in air), mechanical strength, and toughness. The characteristics of the novel BNNTs and BNNT polymer composites and their potential applications are discussed.

  8. CVD mechanism of pyrolytic boron nitride

    International Nuclear Information System (INIS)

    Tanji, H.; Monden, K.; Ide, M.

    1987-01-01

    Pyrolytic boron nitride (P-BN) has become a essential material for III-V compound semiconductor manufacturing process. As the demand from electronics industry for larger single crystals increases, the demand for larger and more economical P-BN components is growing rapidly. P-BN is manufactured by low pressure CVD using boron-trihalides and ammonia as the reactants. In spite that P-BN has been in the market for quite a long time, limited number of fundamental studies regarding the kinetics and the formation mechanism of P-BN have been reported. As it has been demonstrated in CVD of Si, knowledge and both theoretical and empirical modeling of CVD process can be applied to improve the deposition technology and to give more uniform deposition with higher efficiency, and it should also apply to the deposition of P-BN

  9. Microadditions of boron and vanadium in ADI

    Directory of Open Access Journals (Sweden)

    Rzychoń T.

    2007-01-01

    Full Text Available In the second part of the study, describing the role of vanadium and boron microadditions in the process of structure formation in heavy-walled castings made from ADI, the results of own investigations were presented. Within this study two series of melts of the ductile iron were made, introducing microadditions of the above mentioned elements to both unalloyed ductile iron and the ductile iron containing high levels of nickel and copper (the composition typical of ADI. Melts were conducted with iron-nickel-magnesium master alloy. Thermal analysis of the solidification process of the cast keel blocks was conducted, the heat treatment of the alloys was carried out, and then the effect of the introduced additions of boron and vanadium on the hardenability of the investigated cast iron was examined and evaluated.

  10. Boron nitride encapsulated graphene infrared emitters

    International Nuclear Information System (INIS)

    Barnard, H. R.; Zossimova, E.; Mahlmeister, N. H.; Lawton, L. M.; Luxmoore, I. J.; Nash, G. R.

    2016-01-01

    The spatial and spectral characteristics of mid-infrared thermal emission from devices containing a large area multilayer graphene layer, encapsulated using hexagonal boron nitride, have been investigated. The devices were run continuously in air for over 1000 h, with the emission spectrum covering the absorption bands of many important gases. An approximate solution to the heat equation was used to simulate the measured emission profile across the devices yielding an estimated value of the characteristic length, which defines the exponential rise/fall of the temperature profile across the device, of 40 μm. This is much larger than values obtained in smaller exfoliated graphene devices and reflects the device geometry, and the increase in lateral heat conduction within the devices due to the multilayer graphene and boron nitride layers.

  11. Boron nitride encapsulated graphene infrared emitters

    Energy Technology Data Exchange (ETDEWEB)

    Barnard, H. R.; Zossimova, E.; Mahlmeister, N. H.; Lawton, L. M.; Luxmoore, I. J.; Nash, G. R., E-mail: g.r.nash@exeter.ac.uk [College of Engineering, Mathematics and Physical Sciences, University of Exeter, Exeter EX4 4QF (United Kingdom)

    2016-03-28

    The spatial and spectral characteristics of mid-infrared thermal emission from devices containing a large area multilayer graphene layer, encapsulated using hexagonal boron nitride, have been investigated. The devices were run continuously in air for over 1000 h, with the emission spectrum covering the absorption bands of many important gases. An approximate solution to the heat equation was used to simulate the measured emission profile across the devices yielding an estimated value of the characteristic length, which defines the exponential rise/fall of the temperature profile across the device, of 40 μm. This is much larger than values obtained in smaller exfoliated graphene devices and reflects the device geometry, and the increase in lateral heat conduction within the devices due to the multilayer graphene and boron nitride layers.

  12. The spectrophotometric determination of boron in tourmalines

    Directory of Open Access Journals (Sweden)

    LJILJANA JAKSIC

    2005-02-01

    Full Text Available A procedure for the spectrophotometric determination of macro amounts of boron in tourmaline with azomethine H is described. The used tourmaline concentrate was obtained by magnetic separation and heavy-liquids purification of the schorl zone of pegmatite or granite aplite. The samples of tourmaline were decomposed by fusion with anhydrous sodium carbonate and taken up in dilute hydrochloric acid. The interfering effects of iron and aluminium were eliminated by masking with an EDTA – NTA solution. After pH adjustment, the boron was reacted with azomethine H and the absorbance of the obtained coloured complex was measured at 415 nm. The results are compared with those obtained by other procedures. The relative error of the determination was less than 3 %.

  13. Determination of microdistribution of boron in metals

    Energy Technology Data Exchange (ETDEWEB)

    Illic, R; Najzer, M; Rant, J [J. Stefan Institute, Ljubljana (Yugoslavia)

    1976-07-01

    A neutron induced autoradiographic technique was used for the determination of the boron microdistribution in metals. The specimens, which were in close contact with a LR 115 SSTD, were irradiated in the exposure room of the TRIGA Mark II reactor in Ljubljana. The spatial resolution of the autoradiographic image recorded by the LR 115 detector was found to be influenced mainly by the size of the reaction product tracks. The track diameter of a normally etched detector was about 7 {mu}m. An appreciable reduction of track size was achieved by pre-etching the detector foil before neutron irradiation. By this procedure it was possible to obtain a track diameter as small as 1 {mu}m and correspondingly to improve the spatial resolution of the autoradiographs of type EC 80 steel and Al Mg 3 alloy which contain 30 and 2 ppm of boron respectively. (author)

  14. Synthesis and characterization of boron nitrides nanotubes

    International Nuclear Information System (INIS)

    Ferreira, T.H.; Sousa, E.M.B.

    2010-01-01

    This paper presents a new synthesis for the production of boron nitride nanotubes (BNNT) from boron powder, ammonium nitrate and hematite tube furnace CVD method. The samples were subjected to some characterization techniques as infrared spectroscopy, thermal analysis, X-ray diffraction and scanning electron microscopy and transmission. By analyzing the results can explain the chemical reactions involved in the process and confirm the formation of BNNT with several layers and about 30 nanometers in diameter. Due to excellent mechanical properties and its chemical and thermal stability this material is promising for various applications. However, BNNT has received much less attention than carbon nanotubes, it is because of great difficulty to synthesize appreciable quantities from the techniques currently known, and this is one of the main reasons this work.(author)

  15. Grain refinement of cast titanium alloys via trace boron addition

    International Nuclear Information System (INIS)

    Tamirisakandala, S.; Bhat, R.B.; Tiley, J.S.; Miracle, D.B.

    2005-01-01

    The grain size of as-cast Ti-6Al-4V is reduced by about an order of magnitude from 1700 to 200 μm with an addition of 0.1 wt.% boron. A much weaker dependence of reduction in grain size is obtained for boron additions from >0.1% to 1.0%. Similar trends were observed in boron-modified as-cast Ti-6Al-2Sn-4Zr-2Mo-0.1Si

  16. On melting of boron phosphide under pressure

    OpenAIRE

    Solozhenko, Vladimir; Mukhanov, V. A.

    2015-01-01

    Melting of cubic boron phosphide, BP, has been studied at pressures to 9 GPa using synchrotron X-ray diffraction and electrical resistivity measurements. It has been found that above 2.6 GPa BP melts congruently, and the melting curve exhibits negative slope (–60 ± 7 K/GPa), which is indicative of a higher density of the melt as compared to the solid phase.

  17. High resolution imaging of boron carbide microstructures

    International Nuclear Information System (INIS)

    MacKinnon, I.D.R.; Aselage, T.; Van Deusen, S.B.

    1986-01-01

    Two samples of boron carbide have been examined using high resolution transmission electron microscopy (HRTEM). A hot-pressed B 13 C 2 sample shows a high density of variable width twins normal to (10*1). Subtle shifts or offsets of lattice fringes along the twin plane and normal to approx.(10*5) were also observed. A B 4 C powder showed little evidence of stacking disorder in crystalline regions

  18. Contributions to the chemistry of Boron, 112

    International Nuclear Information System (INIS)

    Goetze, R.; Noeth, H.

    1980-01-01

    Several methods were used to prepare a series of boron substituted 1, 3, 2-dithiaborols. The NMR data of this new class of compounds indicate in comparison to 1, 3, 2-dithiaborolanes, that the heterocycle can be looked at as a 6 π-electron system. A high degree of analogy in the mass spectrometric fragmentation of dithiaborolanes and dithiaborols exists, however, the parent ion of 2-methyl dithiaborol is more stable than that of the saturated analogon. (orig.)

  19. Indico CONFERENCE: Define the Call for Abstracts

    CERN Multimedia

    CERN. Geneva; Ferreira, Pedro

    2017-01-01

    In this tutorial, you will learn how to define and open a call for abstracts. When defining a call for abstracts, you will be able to define settings related to the type of questions asked during a review of an abstract, select the users who will review the abstracts, decide when to open the call for abstracts, and more.

  20. Boron neutron capture therapy induces apoptosis of glioma cells through Bcl-2/Bax

    OpenAIRE

    Wang, Peng; Zhen, Haining; Jiang, Xinbiao; Zhang, Wei; Cheng, Xin; Guo, Geng; Mao, Xinggang; Zhang, Xiang

    2010-01-01

    Abstract Background Boron neutron capture therapy (BNCT) is an alternative treatment modality for patients with glioma. The aim of this study was to determine whether induction of apoptosis contributes to the main therapeutic efficacy of BNCT and to compare the relative biological effect (RBE) of BNCT, γ-ray and reactor neutron irradiation. Methods The neutron beam was obtained from the Xi'an Pulsed Reactor (XAPR) and γ-rays were obtained from [60Co] γ source of the Fourth Military Medical Un...

  1. Molecular Dynamics Modeling of Piezoelectric Boron Nirtride Nanotubes

    Data.gov (United States)

    National Aeronautics and Space Administration — Conduct a systematic computational study on the physical and electro-mechanical properties of Boron Nitride Nanotubes (BNNTs) to evaluate their functional...

  2. Combustion Performance of a Staged Hybrid Rocket with Boron addition

    Science.gov (United States)

    Lee, D.; Lee, C.

    2018-04-01

    In this paper, the effect of boron on overall system specific impulse was investigated. Additionally, a series of combustion tests was carried out to analyze and evaluate the effect of boron addition on O/F variation and radial temperature profiles. To maintain the hybrid rocket engine advantages, upper limit of boron contents in solid fuel was set to be 10 wt%. The results also suggested that, when adding boron to solid fuel, it helped to provide more uniform radial temperature distribution and also to increase specific impulse by 3.2%.

  3. Deuterated-decaborane using boronization on JT-60U

    Energy Technology Data Exchange (ETDEWEB)

    Yagyu, Jun-ichi; Arai, Takashi; Kaminaga, Atsushi; Miyata, Katsuyuki [Japan Atomic Energy Research Inst., Naka, Ibaraki (Japan). Naka Fusion Research Establishment; Arai, Masaru [Kaihatsu Denki Co., Ltd., Tokyo (Japan)

    2001-03-01

    In JT-60U, boronization using hydride-decaborane (B{sub 10}H{sub 14}) vaporization has been conducted for the first wall conditioning. Compared to other discharge cleaning (DC), boronization is claimed to be efficient in reduction of oxygen impurities and hydrogen recycling in plasma. However, there are some problems in reduction of hydrogen included in boron film and stabilization of DC glow discharge during the boronization. To solve these problems, a new boronization method using deuterated-decaborane (B{sub 10}D{sub 14}) was adopted instead of the conventional hydride-decaborane. As a result, hydrogen content in the boron film decreased clearly and discharge conditioning shots, for decreasing hydrogen content in plasmas, after the boronization were reduced to 1/10 in comparison to the conventional process. Furthermore, DC glow discharge became stable, with only helium carrier gas, and it was possible to save 30 hours in maximum of the time necessary to boronization. It is shown that the boronization using deuterated-decaborane is very efficient and effective method for the first wall conditioning. (author)

  4. Graphite and boron carbide composites made by hot-pressing

    International Nuclear Information System (INIS)

    Miyazaki, K.; Hagio, T.; Kobayashi, K.

    1981-01-01

    Composites consisting of graphite and boron carbide were made by hot-pressing mixed powders of coke carbon and boron carbide. The change of relative density, mechanical strength and electrical resistivity of the composites and the X-ray parameters of coke carbon were investigated with increase of boron carbide content and hot-pressing temperature. From these experiments, it was found that boron carbide powder has a remarkable effect on sintering and graphitization of coke carbon powder above the hot-pressing temperature of 2000 0 C. At 2200 0 C, electrical resistivity of the composite and d(002) spacing of coke carbon once showed minimum values at about 5 to 10 wt% boron carbide and then increased. The strength of the composite increased with increase of boron carbide content. It was considered that some boron from boron carbide began to diffuse substitutionally into the graphite structure above 2000 0 C and densification and graphitization were promoted with the diffusion of boron. Improvements could be made to the mechanical strength, density, oxidation resistance and manufacturing methods by comparing with the properties and processes of conventional graphites. (author)

  5. Dependence of boron cluster dissolution on the annealing ambient

    International Nuclear Information System (INIS)

    Radic, Ljubo; Lilak, Aaron D.; Law, Mark E.

    2002-01-01

    Boron is introduced into silicon via implantation to form p-type layers. This process creates damage in the crystal that upon annealing causes enhanced diffusion and clustering of the boron layer. Reactivation of the boron is not a well-understood process. In this letter we experimentally investigate the effect of the annealing ambient on boron reactivation kinetics. An oxidizing ambient which injects silicon interstitials is compared to an inert ambient. Contrary to published theory, an excess of interstitials does not accelerate the reactivation process

  6. Tourette Association of America

    Science.gov (United States)

    ... outcomes Find a Doctor Find information for Select Audience Parents Adults with Tourette Kids Teens Educators Professionals ... About Tourette Tourette Association of America Welcomes NFL Marketing Executive Julie Haddon to Its Board of Directors ...

  7. Arthritis in America

    Science.gov (United States)

    ... Digital Press Kit Read the MMWR Science Clips Arthritis in America Time to Take Action! Language: English ( ... by about 40% by being physically active. Problem Arthritis is common and a growing health threat. Arthritis ...

  8. Rediscovering South America

    National Research Council Canada - National Science Library

    Ray, Charles; Shearer, Thomas D; Staszak, Michael

    1997-01-01

    In presenting the U.S. National Security Strategy of Engagement and Enlargement the Clinton Administration states that, "The unprecedented triumph of democracy and market economies throughout the (Latin America...

  9. Paralyzed Veterans of America

    Science.gov (United States)

    ... Connected Twitter @PVA1946 Facebook @Paralyzed Veterans of America Instagram @PVA1946 National Veterans Wheelchair Games App Download Now ... 838-7782 CONNECT WITH US Facebook Twitter YouTube Instagram Flickr STAY INFORMED WITH NEWS & UPDATES Enter your ...

  10. Ion implantation of boron in germanium

    International Nuclear Information System (INIS)

    Jones, K.S.

    1985-05-01

    Ion implantation of 11 B + into room temperature Ge samples leads to a p-type layer prior to any post implant annealing steps. Variable temperature Hall measurements and deep level transient spectroscopy experiments indicate that room temperature implantation of 11 B + into Ge results in 100% of the boron ions being electrically active as shallow acceptor, over the entire dose range (5 x 10 11 /cm 2 to 1 x 10 14 /cm 2 ) and energy range (25 keV to 100 keV) investigated, without any post implant annealing. The concentration of damage related acceptor centers is only 10% of the boron related, shallow acceptor center concentration for low energy implants (25 keV), but becomes dominant at high energies (100 keV) and low doses ( 12 /cm 2 ). Three damage related hole traps are produced by ion implantation of 11 B + . Two of these hole traps have also been observed in γ-irradiated Ge and may be oxygen-vacancy related defects, while the third trap may be divacancy related. All three traps anneal out at low temperatures ( 0 C). Boron, from room temperature implantation of BF 2 + into Ge, is not substitutionally active prior to a post implant annealing step of 250 0 C for 30 minutes. After annealing additional shallow acceptors are observed in BF 2 + implanted samples which may be due to fluorine or flourine related complexes which are electrically active

  11. Considerations for boron neutron capture therapy studies

    International Nuclear Information System (INIS)

    Faria Gaspar, P. de.

    1994-01-01

    Radiotherapy is indispensable as a mean to eradicate deeply or infiltrating tumor tissue that can not be removed surgically. Therefore, it is not selective and may also kill the surrounding health tissue. The principle of BNCT (Boron Neutron Capture Therapy) consist in targeting a tumor selectively with a boron-10 compound. This nuclide has a large capture cross section for thermal neutrons and the nuclear reaction and the delivered energy in locus will selective the tumor. Since its initial proposal in 1963 BNCT has made much progress, however it is not used in a routine treatment. In this work it was approached some complex procedures, as the obtention of selective boron compounds, the adequate set up of neutron beams, the biodistribution, the in vivo and in vitro studies, and also human patients treatments. This work provide fundamentals about BNCT to professional of different areas of knowledge since it comprises multidisciplinary study. It includes appendixes for the ones not related to the field for a better comprehension of the many aspects involved. It is also presented a glossary containing technical and basic aspects involved. It is also presented a glossary containing technical and basic terms referred in the work. (author). 174 refs, 1 fig, 12 apps

  12. Advances in boronization on NSTX-Upgrade

    Directory of Open Access Journals (Sweden)

    C. H Skinner

    2017-08-01

    Full Text Available Boronization has been effective in reducing plasma impurities and enabling access to higher density, higher confinement plasmas in many magnetic fusion devices. The National Spherical Torus eXperiment, NSTX, has recently undergone a major upgrade to NSTX-U in order to develop the physics basis for a ST-based Fusion Nuclear Science Facility (FNSF with capability for double the toroidal field, plasma current, and NBI heating power and increased pulse duration from 1–1.5s to 5–8s. A new deuterated tri-methyl boron conditioning system was implemented together with a novel surface analysis diagnostic. We report on the spatial distribution of the boron deposition versus discharge pressure, gas injection and electrode location. The oxygen concentration of the plasma facing surface was measured by in-vacuo XPS and increased both with plasma exposure and with exposure to trace residual gases. This increase correlated with the rise of oxygen emission from the plasma.

  13. Boron determination in U3O8

    International Nuclear Information System (INIS)

    Ogura, Nadia S.; Sarkis, Jorge E.S.; Rosa, Daniele S.; Ulrich, Joao C.

    2009-01-01

    There exist specifications of the concentration as far the limit of impurities in the used uranium compounds is concerned. Among those impurities the boron element is detached. that in the uranium compounds acts as neutron absorber in nuclear reactions. Therefore, the determination of this element in uranium compounds, it is fundamental for the quality and performance of the nuclear fuels. However, the determination of this element is many times prejudiced by the presence of the uranium. For solving this problem, it is performed a chemical separation of the uranium (matrix) out of the interest. The most used methods to accomplish that separation are the solvent extraction and the ion exchange. In this work, the boron concentration will be done through the ion exchange technique, using polypropylene columns and Dowex AG 50W - X8 100-200 mesh cation resin in chloricide medium 0.25 M. The boron concentration will be determined through high resolution inductive coupling plasma mass spectrometry (HRICP-MS)

  14. Stable boron nitride diamondoids as nanoscale materials

    International Nuclear Information System (INIS)

    Fyta, Maria

    2014-01-01

    We predict the stability of diamondoids made up of boron and nitrogen instead of carbon atoms. The results are based on quantum-mechanical calculations within density functional theory (DFT) and show some very distinct features compared to the regular carbon-based diamondoids. These features are evaluated with respect to the energetics and electronic properties of the boron nitride diamondoids as compared to the respective properties of the carbon-based diamondoids. We find that BN-diamondoids are overall more stable than their respective C-diamondoid counterparts. The electronic band-gaps (E g ) of the former are overall lower than those for the latter nanostructures but do not show a very distinct trend with their size. Contrary to the lower C-diamondoids, the BN-diamondoids are semiconducting and show a depletion of charge on the nitrogen site. Their differences in the distribution of the molecular orbitals, compared to their carbon-based counterparts, offer additional bonding and functionalization possibilities. These tiny BN-based nanostructures could potentially be used as nanobuilding blocks complementing or substituting the C-diamondoids, based on the desired properties. An experimental realization of boron nitride diamondoids remains to show their feasibility. (paper)

  15. Operating System Abstraction Layer (OSAL)

    Science.gov (United States)

    Yanchik, Nicholas J.

    2007-01-01

    This viewgraph presentation reviews the concept of the Operating System Abstraction Layer (OSAL) and its benefits. The OSAL is A small layer of software that allows programs to run on many different operating systems and hardware platforms It runs independent of the underlying OS & hardware and it is self-contained. The benefits of OSAL are that it removes dependencies from any one operating system, promotes portable, reusable flight software. It allows for Core Flight software (FSW) to be built for multiple processors and operating systems. The presentation discusses the functionality, the various OSAL releases, and describes the specifications.

  16. National Physics Conference. Paper Abstracts

    International Nuclear Information System (INIS)

    Marinela Dumitriu, Editorial Coordination.

    1995-01-01

    This book contains the abstracts of the proceedings of the annual Romanian Physics Conference organized by Romanian Physics Society. The conference was held on November 30 to December 2, 1995 in the city of Baia Mare. It was organized in the following nine sections: 1 - Astrophysics, Particle Physics, Nuclear Physics, Molecular and Atomic Physics; 2 - Plasma Physics; 3 - Biophysics; 4 - Technical Physics; 5 - Theoretical Physics; 6 -The Physics of Energy; 7 - The Physics of Environment 8 - Solid State Physics; 9 - Optical and Quantum Electronics. The full texts can be obtained on request from the Romanian Physical Society or directly from authors

  17. In-Package Chemistry Abstraction

    Energy Technology Data Exchange (ETDEWEB)

    P.S. Domski

    2003-07-21

    The work associated with the development of this model report was performed in accordance with the requirements established in ''Technical Work Plan for Waste Form Degradation Modeling, Testing, and Analyses in Support of SR and LA'' (BSC 2002a). The in-package chemistry model and in-package chemistry model abstraction are developed to predict the bulk chemistry inside of a failed waste package and to provide simplified expressions of that chemistry. The purpose of this work is to provide the abstraction model to the Performance Assessment Project and the Waste Form Department for development of geochemical models of the waste package interior. The scope of this model report is to describe the development and validation of the in-package chemistry model and in-package chemistry model abstraction. The in-package chemistry model will consider chemical interactions of water with the waste package materials and the waste form for commercial spent nuclear fuel (CSNF) and codisposed high-level waste glass (HLWG) and N Reactor spent fuel (CDNR). The in-package chemistry model includes two sub-models, the first a water vapor condensation (WVC) model, where water enters a waste package as vapor and forms a film on the waste package components with subsequent film reactions with the waste package materials and waste form--this is a no-flow model, the reacted fluids do not exit the waste package via advection. The second sub-model of the in-package chemistry model is the seepage dripping model (SDM), where water, water that may have seeped into the repository from the surrounding rock, enters a failed waste package and reacts with the waste package components and waste form, and then exits the waste package with no accumulation of reacted water in the waste package. Both of the submodels of the in-package chemistry model are film models in contrast to past in-package chemistry models where all of the waste package pore space was filled with water. The

  18. Abstract decomposition theorem and applications

    CERN Document Server

    Grossberg, R; Grossberg, Rami; Lessmann, Olivier

    2005-01-01

    Let K be an Abstract Elementary Class. Under the asusmptions that K has a nicely behaved forking-like notion, regular types and existence of some prime models we establish a decomposition theorem for such classes. The decomposition implies a main gap result for the class K. The setting is general enough to cover \\aleph_0-stable first-order theories (proved by Shelah in 1982), Excellent Classes of atomic models of a first order tehory (proved Grossberg and Hart 1987) and the class of submodels of a large sequentially homogenuus \\aleph_0-stable model (which is new).

  19. In-Package Chemistry Abstraction

    International Nuclear Information System (INIS)

    P.S. Domski

    2003-01-01

    The work associated with the development of this model report was performed in accordance with the requirements established in ''Technical Work Plan for Waste Form Degradation Modeling, Testing, and Analyses in Support of SR and LA'' (BSC 2002a). The in-package chemistry model and in-package chemistry model abstraction are developed to predict the bulk chemistry inside of a failed waste package and to provide simplified expressions of that chemistry. The purpose of this work is to provide the abstraction model to the Performance Assessment Project and the Waste Form Department for development of geochemical models of the waste package interior. The scope of this model report is to describe the development and validation of the in-package chemistry model and in-package chemistry model abstraction. The in-package chemistry model will consider chemical interactions of water with the waste package materials and the waste form for commercial spent nuclear fuel (CSNF) and codisposed high-level waste glass (HLWG) and N Reactor spent fuel (CDNR). The in-package chemistry model includes two sub-models, the first a water vapor condensation (WVC) model, where water enters a waste package as vapor and forms a film on the waste package components with subsequent film reactions with the waste package materials and waste form--this is a no-flow model, the reacted fluids do not exit the waste package via advection. The second sub-model of the in-package chemistry model is the seepage dripping model (SDM), where water, water that may have seeped into the repository from the surrounding rock, enters a failed waste package and reacts with the waste package components and waste form, and then exits the waste package with no accumulation of reacted water in the waste package. Both of the submodels of the in-package chemistry model are film models in contrast to past in-package chemistry models where all of the waste package pore space was filled with water. The current in

  20. Shoestring Budget Radio Astronomy (Abstract)

    Science.gov (United States)

    Hoot, J. E.

    2017-12-01

    (Abstract only) The commercial exploitation of microwave frequencies for cellular, WiFi, Bluetooth, HDTV, and satellite digital media transmission has brought down the cost of the components required to build an effective radio telescope to the point where, for the cost of a good eyepiece, you can construct and operate a radio telescope. This paper sets forth a family of designs for 1421 MHz telescopes. It also proposes a method by which operators of such instruments can aggregate and archive data via the Internet. With 90 or so instruments it will be possible to survey the entire radio sky for transients with a 24 hour cadence.

  1. Enrichment and desalting of tryptic protein digests and the protein depletion using boron nitride

    Energy Technology Data Exchange (ETDEWEB)

    Fischnaller, Martin; Köck, Rainer; Bakry, Rania, E-mail: rania.bakry@uibk.ac.at; Bonn, Günther K.

    2014-05-01

    Highlights: • Protein tryptic digests were desalted and enriched utilizing hexagonal boron nitride. • Phosphopeptides were desalted with high recovery rates. • Boron nitride exhibits high wettability allowing fast sample preparation. • Boron nitride shows protein depletion capability applied for peptide purification. - Abstract: Sample preparation still remains a great challenge in modern bioanalysis and the interest in new efficient solid phase extraction (SPE) materials still remains high. In this work, hexagonal boron nitride (h-BN) is introduced as a new SPE material for the isolation and enrichment of peptides. The h-BN is isoelectronic and structurally similar to graphite. It has remarkable properties including good thermal conductivity, excellent thermal and chemical stability and a better oxidation resistance than graphite. BN attracts increasing interest because of its wide range of applicability. In the present work, the great potential of h-BN, as a new SPE-material, on the enrichment, preconcentration and desalting of tryptic digest of model proteins is demonstrated. A special attention was dedicated to the efficient enrichment of hydrophilic phosphopeptides. Two elution protocols were developed for the enrichment of peptides compatible for subsequent MALDI-MS and ESI-MS analysis. In addition, the recoveries of 5 peptides and 3 phosphopeptides with wide range of pI values utilizing h-BN materials with different surface areas were investigated. 84–106% recovery rate could be achieved using h-BN materials. The results were compared with those obtained using graphite and silica C18 under the same elution conditions, and lower recoveries were obtained. In addition, h-BN was found to have a capability of protein depletion, which is requisite for the peptide profiling.

  2. Enrichment and desalting of tryptic protein digests and the protein depletion using boron nitride

    International Nuclear Information System (INIS)

    Fischnaller, Martin; Köck, Rainer; Bakry, Rania; Bonn, Günther K.

    2014-01-01

    Highlights: • Protein tryptic digests were desalted and enriched utilizing hexagonal boron nitride. • Phosphopeptides were desalted with high recovery rates. • Boron nitride exhibits high wettability allowing fast sample preparation. • Boron nitride shows protein depletion capability applied for peptide purification. - Abstract: Sample preparation still remains a great challenge in modern bioanalysis and the interest in new efficient solid phase extraction (SPE) materials still remains high. In this work, hexagonal boron nitride (h-BN) is introduced as a new SPE material for the isolation and enrichment of peptides. The h-BN is isoelectronic and structurally similar to graphite. It has remarkable properties including good thermal conductivity, excellent thermal and chemical stability and a better oxidation resistance than graphite. BN attracts increasing interest because of its wide range of applicability. In the present work, the great potential of h-BN, as a new SPE-material, on the enrichment, preconcentration and desalting of tryptic digest of model proteins is demonstrated. A special attention was dedicated to the efficient enrichment of hydrophilic phosphopeptides. Two elution protocols were developed for the enrichment of peptides compatible for subsequent MALDI-MS and ESI-MS analysis. In addition, the recoveries of 5 peptides and 3 phosphopeptides with wide range of pI values utilizing h-BN materials with different surface areas were investigated. 84–106% recovery rate could be achieved using h-BN materials. The results were compared with those obtained using graphite and silica C18 under the same elution conditions, and lower recoveries were obtained. In addition, h-BN was found to have a capability of protein depletion, which is requisite for the peptide profiling

  3. A critical assessment of boron target compounds for boron neutron capture therapy.

    Science.gov (United States)

    Hawthorne, M Frederick; Lee, Mark W

    2003-01-01

    Boron neutron capture therapy (BNCT) has undergone dramatic developments since its inception by Locher in 1936 and the development of nuclear energy during World War II. The ensuing Cold War spawned the entirely new field of polyhedral borane chemistry, rapid advances in nuclear reactor technology and a corresponding increase in the number to reactors potentially available for BNCT. This effort has been largely oriented toward the eradication of glioblastoma multiforme (GBM) and melanoma with reduced interest in other types of malignancies. The design and synthesis of boron-10 target compounds needed for BNCT was not channeled to those types of compounds specifically required for GBM or melanoma. Consequently, a number of potentially useful boron agents are known which have not been biologically evaluated beyond a cursory examination and only three boron-10 enriched target species are approved for human use following their Investigational New Drug classification by the US Food and Drug Administration; BSH, BPA and GB-10. All ongoing clinical trials with GBM and melanoma are necessarily conducted with one of these three species and most often with BPA. The further development of BNCT is presently stalled by the absence of strong support for advanced compound evaluation and compound discovery driven by recent advances in biology and chemistry. A rigorous demonstration of BNCT efficacy surpassing that of currently available protocols has yet to be achieved. This article discusses the past history of compound development, contemporary problems such as compound classification and those problems which impede future advances. The latter include means for biological evaluation of new (and existing) boron target candidates at all stages of their development and the large-scale synthesis of boron target species for clinical trials and beyond. The future of BNCT is bright if latitude is given to the choice of clinical disease to be treated and if a recognized study

  4. Determination of isotopic composition of boron in boron carbide by TIMS and PIGE: an inter-comparison study

    International Nuclear Information System (INIS)

    Sasibhushan, K.; Rao, R.M.; Parab, A.R.; Alamelu, D.; Aggarwal, S.K.; Acharya, R.; Chhillar, S.; Pujari, P.K.

    2015-01-01

    The paper reports a comparison of results on the determination of isotopic composition of boron in boron carbide (B 4 C) samples by Thermal Ionisation Mass Spectrometry (TIMS) and Particle Induced Gamma ray Spectrometry (PIGE). B 4 C samples having varying boron isotopic composition (natural, enriched with respect to 10 B) and their synthetic mixtures) have been analysed by both the techniques. The 10 B atom% was found to be in the range of 20-67%. (author)

  5. Boron neutron capture therapy. Synthesis of boronated amines- and DNA intercalating agents for potential use in cancer therapy

    International Nuclear Information System (INIS)

    Ghaneolhosseini, H.

    1998-01-01

    Boron Neutron Capture Therapy is a binary cancer treatment modality, involving the delivery of a suitable boron compound to tumour cells followed by irradiation of the tumour by thermal neutrons. Boronated agents can selectively be delivered to tumour cells either directly with tumour-specific boron compounds, or by use of targeting strategies. However, the efficacy of this method would increase if the boron agents are localised in the cell nucleus rather than in the cell cytoplasm when neutron irradiation takes place. With these considerations in mind, some boronated DNA intercalating/interacting agents such as phenanthridine- acridine- spermidine- and naphthalimide derivatives were synthesised. Aminoalkyl-o-carboranes were synthesised in order to be used both for coupling to macromolecules and also for halogenation of their corresponding nido-derivatives. The amino groups were introduced using the Gabriel reagent N, N-dibenzyl iminodicarboxylate to provide 1-(aminomethyl)- and 1-(2-aminoethyl)-o-carboranes. The first attempt to achieve the possibility to accumulate a higher concentration of boron atoms in the cell nucleus was to synthesize carboranyl phenanthridinium analogues by reacting a p- or o-carboranyl moiety with phenanthridine, a chromophore with a planar aromatic ring system as DNA intercalator. Boronated acridine-spermidine, boronated diacridine, and boronated dispermidine were obtained in order to increase water solubility to avoid the interaction of these agents with non-DNA sides of the cell, especially membranes; and to enhance the feasibility of a higher DNA-binding constant and also decrease the DNA-drug dissociation rate. Finally, the synthesis of a boronated naphthalimide derivative was carried out by nucleophilic reaction of a primary aminoalkyl-p-carborane with naphthalic anhydride. Biological evaluations on DNA-binding, toxicity, and cellular binding with carboranyl phenanthridinium analogues, boronated acridine- and spermidine are described

  6. Determination of boron in graphite, boron carbide and glass by ICP-MS, ICP-OES and conventional wet chemical methods

    International Nuclear Information System (INIS)

    Venkatesh, K.; Kamble, Granthali S.; Venkatesh, Manisha; Kumar, Sanjukta A.; Reddy, A.V.R.

    2014-01-01

    Boron is an important element of interest in nuclear reactor materials due to its high neutron absorption cross section (σ 0 =3837 barns for 10 B). In the present paper, R and D work and routinely used methods have been described for the analysis of case samples (1) Graphite where boron is present at trace levels, (2) Boron Carbide having boron concentration of about 80% and (3) Glass containing 4-6 % boron. (author)

  7. Effect of boron and carbon addition on microstructure and mechanical properties of Ti-15-3 alloy

    International Nuclear Information System (INIS)

    Sarkar, R.; Ghosal, P.; Muraleedharan, K.; Nandy, T.K.; Ray, K.K.

    2011-01-01

    Highlights: → Development of β Ti alloys with B and C addition for improved mechanical properties. → Detailed characterization of microstructural constituents using electron microscopy. → Microstructure-mechanical property correlation in this new class of alloys. → Strengthening mechanism in β Ti alloy in the presence of hard and non-deformable phases. - Abstract: A detailed microstructure-mechanical property correlation was carried out in beta titanium alloys (Ti-15V-3Al-3Sn-3Cr) with boron and carbon additions. The alloys were prepared by non-consumable vacuum arc melting followed by hot rolling. Microstructural characterization was carried out using an optical microscope, a scanning electron microscope (SEM), a transmission electron microscope (TEM) and a high resolution TEM (HRTEM). Addition of boron and carbon resulted in the precipitation of TiB and TiC, respectively, and these phases acted as reinforcements. Evaluation of mechanical properties in solution treated and solution treated plus aged condition showed strengthening in the boron and carbon containing alloy with respect to the base. Strengthening in solution treated condition was attributed to a synergistic effect of grain refinement and load transfer in the presence of non-deformable phases. On the other hand, higher strength in boron and carbon containing alloys on aging was ascribed to the presence of finer aged microstructures.

  8. A self-propagation high-temperature synthesis and annealing route to synthesis of wave-like boron nitride nanotubes

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Jilin; Zhang, Laiping [School of Materials Science and Engineering, Wuhan Institute of Technology, Wuhan, Hubei, 430073 (China); Gu, Yunle, E-mail: ncm@mail.wit.edu.cn [School of Materials Science and Engineering, Wuhan Institute of Technology, Wuhan, Hubei, 430073 (China); Pan, Xinye; Zhao, Guowei; Zhang, Zhanhui [School of Materials Science and Engineering, Wuhan Institute of Technology, Wuhan, Hubei, 430073 (China)

    2013-03-15

    Highlights: ► Large quantities of wave-like BN nanotubes were synthesized by SHS-annealing method. ► The catalytic boron-containing porous precursor was produced by self-propagation high-temperature synthesis method. ► Three growth models were proposed to explain the growth mechanism of the wave-like BN nanotubes. - Abstract: Large quantities of boron nitride (BN) nanotubes were synthesized by annealing a catalytic boron-containing porous precursor in flowing NH{sub 3} gas at 1180 °C. The porous precursor was prepared by self-propagation high-temperature synthesis (SHS) method at 800 °C using Mg, B{sub 2}O{sub 3} and amorphous boron powder (α-B) as the starting materials. The porous precursor played an important role in large quantities synthesis of BN nanotubes. The as-synthesized product was characterized by X-ray diffractometer (XRD), Fourier transform infrared spectrometer (FTIR), Raman, Scanning electron microscopy (SEM), X-ray energy dispersive spectroscopy (EDS), Transmission electron microscopy (TEM) and High-resolution transmission electron microscopy (HRTEM). Characterization results indicated that the BN nanotubes displayed wave-like inner structures with diameters in the range of 50–300 nm and average lengths of more than 10 μm. The possible growth mechanism of the BN nanotubes was also discussed.

  9. Reconstruction of abstract quantum theory

    International Nuclear Information System (INIS)

    Drieschner, M.; Goernitz, T.; von Weizsaecker, C.F.

    1988-01-01

    Understanding quantum theory as a general theory of prediction, we reconstruct abstract quantum theory. Abstract means the general frame of quantum theory, without reference to a three-dimensional position space, to concepts like particle or field, or to special laws of dynamics. Reconstruction is the attempt to do this by formulating simple and plausible postulates on prediction in order to derive the basic concepts of quantum theory from them. Thereby no law of classical physics is presupposed which would then have to be quantized. We briefly discuss the relationship of theory and interpretation in physics and the fundamental role of time as a basic concept for physics. Then a number of assertions are given, formulated as succinctly as possible in order to make them easily quotable and comparable. The assertations are arranged in four groups: heuristic principles, verbal definitions of some terms, three basic postulates, and consequences. The three postulates of separable alternatives, indeterminism, and kinematics are the central points of this work. These brief assertions are commented upon, and their relationship with the interpretation of quantum theory is discussed. Also given are an outlook on the further development into concrete quantum theory and some philosophical reflections

  10. An introduction to abstract algebra

    CERN Document Server

    Robinson, Derek JS

    2003-01-01

    This is a high level introduction to abstract algebra which is aimed at readers whose interests lie in mathematics and in the information and physical sciences. In addition to introducing the main concepts of modern algebra, the book contains numerous applications, which are intended to illustrate the concepts and to convince the reader of the utility and relevance of algebra today. In particular applications to Polya coloring theory, latin squares, Steiner systems and error correcting codes are described. Another feature of the book is that group theory and ring theory are carried further than is often done at this level. There is ample material here for a two semester course in abstract algebra. The importance of proof is stressed and rigorous proofs of almost all results are given. But care has been taken to lead the reader through the proofs by gentle stages. There are nearly 400 problems, of varying degrees of difficulty, to test the reader''s skill and progress. The book should be suitable for students ...

  11. Synovectomy by neutron capture in boron

    International Nuclear Information System (INIS)

    Vega C, H.R.

    2002-01-01

    The rheumatoid arthritis is an illness which affect approximately at 3% of the World population. This illness is characterized by the inflammation of the joints which reduces the quality of life and the productivity of the patients. Since, it is an autoimmune illness, the inflammation is due to the overproduction of synovial liquid by the increase in the quantity of synoviocytes. The rheumatoid arthritis does not have a definitive recovery and the patients have three options of treatment: the use of drugs, the surgery and the radio synovectomy. The synovectomy by neutron capture in Boron is a novel proposal of treatment of the rheumatoid arthritis that consists in using a charged compound with Boron 10 that is preferently incorporated in the synoviocytes and to a less extent in the rest of surrounding tissues of the joint. Then, the joint is exposed to a thermal neutron field that induces the reaction (n, α) in the 10 B. the products of this reaction place their energy inside synoviocytes producing their reduction and therefore the reduction of the joint inflammation. Since it is a novel procedure, the synovectomy by neutron capture in boron has two problems: the source design and the design of the adequate drug. In this work it has been realized a Monte Carlo study with the purpose to design a moderating medium that with a 239 Pu Be source in its center, produces a thermal neutron field. With the produced neutron spectra, the neutrons spectra and neutron doses were calculated in different sites inside a model of knee joint. In Monte Carlo studies it is necessary to know the elemental composition of all the joint components, for the case of synovia and the synovial liquid this information does not exist in such way that it is supposed that its composition is equal than the water. In this work also it has been calculated the kerma factors by neutrons of synovia and the synovial liquid supposing that their elemental composition are similar to the blood tissue

  12. An empirical model for parameters affecting energy consumption in boron removal from boron-containing wastewaters by electrocoagulation.

    Science.gov (United States)

    Yilmaz, A Erdem; Boncukcuoğlu, Recep; Kocakerim, M Muhtar

    2007-06-01

    In this study, it was investigated parameters affecting energy consumption in boron removal from boron containing wastewaters prepared synthetically, via electrocoagulation method. The solution pH, initial boron concentration, dose of supporting electrolyte, current density and temperature of solution were selected as experimental parameters affecting energy consumption. The obtained experimental results showed that boron removal efficiency reached up to 99% under optimum conditions, in which solution pH was 8.0, current density 6.0 mA/cm(2), initial boron concentration 100mg/L and solution temperature 293 K. The current density was an important parameter affecting energy consumption too. High current density applied to electrocoagulation cell increased energy consumption. Increasing solution temperature caused to decrease energy consumption that high temperature decreased potential applied under constant current density. That increasing initial boron concentration and dose of supporting electrolyte caused to increase specific conductivity of solution decreased energy consumption. As a result, it was seen that energy consumption for boron removal via electrocoagulation method could be minimized at optimum conditions. An empirical model was predicted by statistically. Experimentally obtained values were fitted with values predicted from empirical model being as following; [formula in text]. Unfortunately, the conditions obtained for optimum boron removal were not the conditions obtained for minimum energy consumption. It was determined that support electrolyte must be used for increase boron removal and decrease electrical energy consumption.

  13. Boron Removal in Radioactive Liquid Waste by Forward Osmosis Membrane

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, Dooseong; Choi, Hei Min; Lee, Kune Woo; Moon Jeikwon [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2014-05-15

    These wastes contain about 0.3-0.8 wt% boric acid and have been concentrated through an evaporation treatment. Boric acid tends to crystallize owing to its solubility, and to plug the evaporator. The volume reduction obtained through evaporation is limited by the amount of boric acid in the waste. As an emerging technology, forward osmosis (FO) has attracted growing interest in wastewater treatment and desalination. FO is a membrane process in which water flows across a semi-permeable membrane from a feed solution of lower osmotic pressure to a draw solution of higher osmotic pressure. However, very few studies on the removal of boron by FO have been performed. The objective of this study is to evaluate the possibility of boron separation in radioactive liquid waste by FO. In this study, the performance of FO was investigated to separate boron in the simulated liquid waste under the factors such as pH, osmotic pressure, ionic strength of the solution, and membrane characteristic. The boron separation in radioactive borate liquid waste was investigated with an FO membrane. When the feed solution containing boron is treated by the FO membrane, the boron permeation depends on the type of membrane, membrane orientation, pH of the feed solution, salt and boron concentration in the feed solution, and osmotic pressure of the draw solution. The boron flux begins to decline from pH 7, and increases with an increase in the osmotic driving force. The boron flux of the CTA-ES and ALFD membrane orientation is higher than those of the CTA-NW and ALFF orientation, respectively. The boron permeation rate is constant regardless of the osmotic pressure and membrane orientation. The boron flux decreases slightly with the salt concentration, but it is not heavily influenced at a low salt concentration.

  14. Boron Removal in Radioactive Liquid Waste by Forward Osmosis Membrane

    International Nuclear Information System (INIS)

    Hwang, Dooseong; Choi, Hei Min; Lee, Kune Woo; Moon Jeikwon

    2014-01-01

    These wastes contain about 0.3-0.8 wt% boric acid and have been concentrated through an evaporation treatment. Boric acid tends to crystallize owing to its solubility, and to plug the evaporator. The volume reduction obtained through evaporation is limited by the amount of boric acid in the waste. As an emerging technology, forward osmosis (FO) has attracted growing interest in wastewater treatment and desalination. FO is a membrane process in which water flows across a semi-permeable membrane from a feed solution of lower osmotic pressure to a draw solution of higher osmotic pressure. However, very few studies on the removal of boron by FO have been performed. The objective of this study is to evaluate the possibility of boron separation in radioactive liquid waste by FO. In this study, the performance of FO was investigated to separate boron in the simulated liquid waste under the factors such as pH, osmotic pressure, ionic strength of the solution, and membrane characteristic. The boron separation in radioactive borate liquid waste was investigated with an FO membrane. When the feed solution containing boron is treated by the FO membrane, the boron permeation depends on the type of membrane, membrane orientation, pH of the feed solution, salt and boron concentration in the feed solution, and osmotic pressure of the draw solution. The boron flux begins to decline from pH 7, and increases with an increase in the osmotic driving force. The boron flux of the CTA-ES and ALFD membrane orientation is higher than those of the CTA-NW and ALFF orientation, respectively. The boron permeation rate is constant regardless of the osmotic pressure and membrane orientation. The boron flux decreases slightly with the salt concentration, but it is not heavily influenced at a low salt concentration

  15. Abstract Expression Grammar Symbolic Regression

    Science.gov (United States)

    Korns, Michael F.

    This chapter examines the use of Abstract Expression Grammars to perform the entire Symbolic Regression process without the use of Genetic Programming per se. The techniques explored produce a symbolic regression engine which has absolutely no bloat, which allows total user control of the search space and output formulas, which is faster, and more accurate than the engines produced in our previous papers using Genetic Programming. The genome is an all vector structure with four chromosomes plus additional epigenetic and constraint vectors, allowing total user control of the search space and the final output formulas. A combination of specialized compiler techniques, genetic algorithms, particle swarm, aged layered populations, plus discrete and continuous differential evolution are used to produce an improved symbolic regression sytem. Nine base test cases, from the literature, are used to test the improvement in speed and accuracy. The improved results indicate that these techniques move us a big step closer toward future industrial strength symbolic regression systems.

  16. WIPR-2010 Book of abstracts

    International Nuclear Information System (INIS)

    2015-01-01

    The main objective of the workshop was to review advanced and preclinical studies on innovative positron emitting radionuclides to assess their usefulness and potentials. Presentations were organized around 4 issues: 1) preclinical and clinical point of view, 2) production of innovative PET radionuclides, 3) from complexation chemistry to PET imaging and 4) from research to clinic. Emphasis has been put on "6"4Cu, "6"8Ga, "8"9Zr, "4"4Sc but specific aspects such as production or purification have been considered for "6"6Ga, "6"7Ga, "5"2Fe, "8"6Y, and "6"8Ge radionuclides. This document gathers the abstracts of most contributions

  17. Abstract algebra an introductory course

    CERN Document Server

    Lee, Gregory T

    2018-01-01

    This carefully written textbook offers a thorough introduction to abstract algebra, covering the fundamentals of groups, rings and fields. The first two chapters present preliminary topics such as properties of the integers and equivalence relations. The author then explores the first major algebraic structure, the group, progressing as far as the Sylow theorems and the classification of finite abelian groups. An introduction to ring theory follows, leading to a discussion of fields and polynomials that includes sections on splitting fields and the construction of finite fields. The final part contains applications to public key cryptography as well as classical straightedge and compass constructions. Explaining key topics at a gentle pace, this book is aimed at undergraduate students. It assumes no prior knowledge of the subject and contains over 500 exercises, half of which have detailed solutions provided.

  18. Norddesign 2012 - Book of Abstract

    DEFF Research Database (Denmark)

    . Conceptualisation and Innovative thinking. Research approaches and topics: Human Behaviour and Cognition. Cooperation and Multidisciplinary Design. Staging and Management of Design. Communication in Design. Design education and teaching: Programmes and Syllabuses. New Courses. Integrated and Multi-disciplinary. We...... fate of the ideas behind the conferences. In that view the conferences have been thematically open and the organization has been tight with a limited number of participants that allows a good overview of all the papers and a lot of informal discussion between the participants. The present conference...... has been organized in line with the original ideas. The topics mentioned in the call for abstracts were: Product Development: Integrated, Multidisciplinary, Product life oriented and Distributed. Multi-product Development. Innovation and Business Models. Engineering Design and Industrial Design...

  19. Spectrophotometry of Symbiotic Stars (Abstract)

    Science.gov (United States)

    Boyd, D.

    2017-12-01

    (Abstract only) Symbiotic stars are fascinating objects - complex binary systems comprising a cool red giant star and a small hot object, often a white dwarf, both embedded in a nebula formed by a wind from the giant star. UV radiation from the hot star ionizes the nebula, producing a range of emission lines. These objects have composite spectra with contributions from both stars plus the nebula and these spectra can change on many timescales. Being moderately bright, they lend themselves well to amateur spectroscopy. This paper describes the symbiotic star phenomenon, shows how spectrophotometry can be used to extract astrophysically useful information about the nature of these systems, and gives results for three symbiotic stars based on the author's observations.

  20. Transplantation as an abstract good

    DEFF Research Database (Denmark)

    Hoeyer, Klaus; Jensen, Anja Marie Bornø; Olejaz, Maria

    2015-01-01

    This article investigates valuations of organ transfers that are currently seen as legitimising increasingly aggressive procurement methods in Denmark. Based on interviews with registered donors and the intensive care unit staff responsible for managing organ donor patients we identify three types...... a more general salience in the organ transplant field by way of facilitating a perception of organ transplantation as an abstract moral good rather than a specific good for specific people. Furthermore, we suggest that multiple forms of ignorance sustain each other: a desire for ignorance with respect...... to the prioritisation of recipients sustains pressure for more organs; this pressure necessitates more aggressive measures in organ procurement and these measures increase the need for ignorance in relation to the actual procedures as well as the actual recipients. These attempts to avoid knowledge are in remarkable...

  1. Degradation of interface between boron subphthalocyanine chloride and fullerene

    Energy Technology Data Exchange (ETDEWEB)

    Lo, Ming-Fai; Guan, Zhi-Qiang [Center of Super-Diamond and Advanced Films (COSDAF), Department of Physics and Materials Science, City University of Hong Kong, Hong Kong SAR (China); City University of Hong Kong Shenzhen Research Institute, Shenzhen (China); Chan, Chiu-Yee [Center of Super-Diamond and Advanced Films (COSDAF), Department of Physics and Materials Science, City University of Hong Kong, Hong Kong SAR (China); Ng, Tsz-Wai, E-mail: tszwaing@cityu.edu.hk [Center of Super-Diamond and Advanced Films (COSDAF), Department of Physics and Materials Science, City University of Hong Kong, Hong Kong SAR (China); City University of Hong Kong Shenzhen Research Institute, Shenzhen (China); Lee, Chun-Sing, E-mail: apcslee@cityu.edu.hk [Center of Super-Diamond and Advanced Films (COSDAF), Department of Physics and Materials Science, City University of Hong Kong, Hong Kong SAR (China); City University of Hong Kong Shenzhen Research Institute, Shenzhen (China)

    2015-10-01

    Highlights: • SubPc/C{sub 60} device shows a fast Voc decade upon operation. • The HOMO-LUMO offset at a SubPc/C60 heterojunction decreases from 1.66 to 1.45 eV upon aging in UHV. • It is caused by internal deterioration of the donor/acceptor interface. - Abstract: Apart from external environmental factors, we herein show with ultra-violet photoemission spectroscopy (UPS) studies that degradation in organic photovoltaic (OPV) devices can also be caused by internal deterioration of the donor/acceptor interface. Albeit with impressive initial open circuit voltage (Voc), boron subphthalocyanine chloride (SubPc)/fullerene (C{sub 60}) device shows a fast Voc decade upon operation. UPS results show that the energy offset between the highest occupied molecular orbit (HOMO) of SubPc and the lowest unoccupied molecular orbit (LUMO) of C{sub 60} is reduced from 1.66 to 1.45 eV after aging in ultra-high vacuum (UHV) condition. This result is consistent with the change in built-in voltage of the corresponding device upon operation. The related charge interaction and degradation mechanism in the SubPc/C{sub 60} device are discussed.

  2. Degradation of interface between boron subphthalocyanine chloride and fullerene

    International Nuclear Information System (INIS)

    Lo, Ming-Fai; Guan, Zhi-Qiang; Chan, Chiu-Yee; Ng, Tsz-Wai; Lee, Chun-Sing

    2015-01-01

    Highlights: • SubPc/C 60 device shows a fast Voc decade upon operation. • The HOMO-LUMO offset at a SubPc/C60 heterojunction decreases from 1.66 to 1.45 eV upon aging in UHV. • It is caused by internal deterioration of the donor/acceptor interface. - Abstract: Apart from external environmental factors, we herein show with ultra-violet photoemission spectroscopy (UPS) studies that degradation in organic photovoltaic (OPV) devices can also be caused by internal deterioration of the donor/acceptor interface. Albeit with impressive initial open circuit voltage (Voc), boron subphthalocyanine chloride (SubPc)/fullerene (C 60 ) device shows a fast Voc decade upon operation. UPS results show that the energy offset between the highest occupied molecular orbit (HOMO) of SubPc and the lowest unoccupied molecular orbit (LUMO) of C 60 is reduced from 1.66 to 1.45 eV after aging in ultra-high vacuum (UHV) condition. This result is consistent with the change in built-in voltage of the corresponding device upon operation. The related charge interaction and degradation mechanism in the SubPc/C 60 device are discussed.

  3. Boron nitride hollow nanospheres: Synthesis, formation mechanism and dielectric property

    Energy Technology Data Exchange (ETDEWEB)

    Zhong, B.; Tang, X.H. [School of Materials Science and Engineering, Harbin Institute of Technology at Weihai, Weihai 264209 (China); Huang, X.X., E-mail: swliza@hit.edu.cn [School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001 (China); Xia, L. [School of Materials Science and Engineering, Harbin Institute of Technology at Weihai, Weihai 264209 (China); Zhang, X.D. [School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001 (China); Wang, C.J. [School of Materials Science and Engineering, Harbin Institute of Technology at Weihai, Weihai 264209 (China); Wen, G.W., E-mail: g.wen@hit.edu.cn [School of Materials Science and Engineering, Harbin Institute of Technology at Weihai, Weihai 264209 (China); School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001 (China)

    2015-04-15

    Highlights: • BN hollow nanospheres are fabricated in large scale via a new CVD method. • Morphology and structure are elucidated by complementary analytical techniques. • Formation mechanism is proposed based on experimental observations. • Dielectric properties are investigated in the X-band microwave frequencies. • BN hollow nanospheres show lower dielectric loss than regular BN powders. - Abstract: Boron nitride (BN) hollow nanospheres have been successfully fabricated by pyrolyzing vapors decomposed from ammonia borane (NH{sub 3}BH{sub 3}) at 1300 °C. The final products have been extensively characterized by X-ray diffraction, field-emission scanning electron microscopy, transmission electron microscopy, and X-ray photoelectron spectroscopy. The BN hollow nanospheres were ranging from 100 to 300 nm in diameter and around 30–100 nm in thickness. The internal structure of the products was found dependent on the reaction temperatures. A possible formation mechanism of the BN hollow nanospheres was proposed on the basis of the experimental observations. Dielectric measurements in the X-band microwave frequencies (8–12 GHz) showed that the dielectric loss of the paraffin filled by the BN hollow nanospheres was lower than that filled by regular BN powders, which indicated that the BN hollow nanospheres could be potentially used as low-density fillers for microwave radomes.

  4. High pressure synthesis and investigations of properties of boron allotropes and boron carbide

    International Nuclear Information System (INIS)

    Chuvashova, Irina

    2017-01-01

    This work aimed at the development of the high-pressure high-temperature (HPHT) synthesis of single crystals of boron allotropes and boron-rich compounds, which could be used further for precise investigations of their structures, properties, and behavior at extreme conditions. To summarize, the present work resulted in the HPHT synthesis of the first previously unknown non-icosahedral boron allotrope ζ-B. This finding confirmed earlier theoretical predictions, which stayed unproven for decades because of experimental challenges which couldn't be overcome until recently. Structural stability of α-B and β-B in the Mbar pressure range and B 13 C 2 up to 68 GPa was experimentally proven. Accurate measurements of the unit cell and B 12 icosahedra volumes of the stoichiometric boron carbide B 13 C 2 as a function of pressure led to conclusion that they undergo a similar reduction upon compression that is typical for covalently bonded solids. Neither 'molecular-like' nor 'inversed molecular-like' solid behavior upon compression was detected that has closed a long-standing scientific dispute. A comparison of the compressional behavior of B 13 C 2 with that of α-B and γ-B allotropes and B 4 C showed that it is determined by the types of bonding involved in the course of compression.

  5. Comparison of boron and neon damage effects in boron ion-implanted resistors

    International Nuclear Information System (INIS)

    MacIver, B.A.

    1975-01-01

    Boron and neon damage implants were used in fabricating integrated-circuit resistors in silicon. Resistor properties were studied as functions of damaging ion species and dose. Sheet resistances in the 10 000 Ω/square range were obtained with low temperature and voltage sensitivities and d.c. isolation. (author)

  6. From boron analogues of amino acids to boronated DNA: potential new pharmaceuticals and neutron capture agents

    International Nuclear Information System (INIS)

    Spielvogel, B.F.; Sood, Anup; Duke Univ., Durham, NC; Shaw, B.R.; Hall, I.H.

    1991-01-01

    Isoelectronic and isostructural boron analogues of the α-amino acids ranging from simple glycine analogues such as H 3 NBH 2 COOH and Me 2 NHBH 2 COOH to alanine analogues have been synthesised. A diverse variety of analogues, including precursors and derivatives (such as peptides) have potent pharmacological activity, including anticancer, antiinflammatory, analgesic, and hypolipidemic activity in animal model studies and in vitro cell cultures. Boronated nucleosides and (oligo)nucleotides, synthetic oligonucleotide analogues of ''antisense'' agents interact with a complementary nucleic acid sequence blocking the biological effect of the target sequence. Nucleosides boronated on the pyrimidine and purine bases have been prepared. It has been established that an entirely new class of nucleic acid derivatives is feasible in which one of the non-bridging oxygens in the internucleotide phosphodiester linkage can be replaced by an isoelectronic analogue, the borane group, (BH 3 ). The boronated oligonucleotides can be viewed as hybrids of the normal oxygen oligonucleotides and the methylphosphonate oligonucleotides. (author)

  7. Investigation of Hard Boron Rich Solids: Osmium Diboride and β-Rhombohedral Boron

    Science.gov (United States)

    Hebbache, M.; Živković, D.

    Recently, we succeeded in synthesizing three osmium borides, i.e., OsB1.1, Os2B3 and OsB2. Up to date, almost nothing is known about the physical properties of these materials. Microhardness measurements show that OsB2 is extremely hard. Ab initio calculations show that it is due to formation of covalent bonds between boron atoms. OsB2 is also a low compressibility material. It can be used for hard coatings. The β-rhombohedral polymorph of boron is the second hardest elemental crystal (H ≈ 33 GPa). It is also very light and a p-type semiconductor. In early 1970s, it has been shown that the doping of boron with 3d transition elements enhances its hardness by about 25%. We predict that, in general, heavily doped samples MBx, with x ≤ 31 or equivalently a dopant concentration larger than 3.2 at.%, should be ultrahard, i.e., H > 43 GPa. The relevant dopants M are Al, Cu, Sc, Mn, Mg and Li. In addition to these properties, boron-rich materials have a very low volatility, a high chemical inertness and high melting point. They are suitable for applications under extreme conditions and thermoelectric equipment.

  8. Boron distribution and the effect of lime on boron uptake by pansy, petunia, and gerbera plants

    Science.gov (United States)

    Reports of boron (B) deficiency have become more prevalent in pansy (Viola ×wittrockiana), petunia (Petunia ×hybrida), and gerbera (Gerbera jamesonii) plug production. When symptoms are observed in production the presence and severity of symptoms have no pattern, symptomatic plants can be located a...

  9. High pressure synthesis and investigations of properties of boron allotropes and boron carbide

    Energy Technology Data Exchange (ETDEWEB)

    Chuvashova, Irina

    2017-06-12

    This work aimed at the development of the high-pressure high-temperature (HPHT) synthesis of single crystals of boron allotropes and boron-rich compounds, which could be used further for precise investigations of their structures, properties, and behavior at extreme conditions. To summarize, the present work resulted in the HPHT synthesis of the first previously unknown non-icosahedral boron allotrope ζ-B. This finding confirmed earlier theoretical predictions, which stayed unproven for decades because of experimental challenges which couldn't be overcome until recently. Structural stability of α-B and β-B in the Mbar pressure range and B{sub 13}C{sub 2} up to 68 GPa was experimentally proven. Accurate measurements of the unit cell and B{sub 12} icosahedra volumes of the stoichiometric boron carbide B{sub 13}C{sub 2} as a function of pressure led to conclusion that they undergo a similar reduction upon compression that is typical for covalently bonded solids. Neither 'molecular-like' nor 'inversed molecular-like' solid behavior upon compression was detected that has closed a long-standing scientific dispute. A comparison of the compressional behavior of B{sub 13}C{sub 2} with that of α-B and γ-B allotropes and B{sub 4}C showed that it is determined by the types of bonding involved in the course of compression.

  10. Dynamic response of multiwall boron nitride nanotubes subjected to ...

    Indian Academy of Sciences (India)

    Page 1 ... 1. Introduction. Boron nitride nanotubes (BNNTs) are like carbon nanotubes. (CNTs) in structure in which carbon atoms are replaced by alternate boron and nitrogen atoms. Thus, BNNTs demon- ... istic analyser for intermediate landing situation of inserted mass.15 Also, a macroscopic continuum simulation is sug-.

  11. Highly thermal conductive carbon fiber/boron carbide composite material

    International Nuclear Information System (INIS)

    Chiba, Akio; Suzuki, Yasutaka; Goto, Sumitaka; Saito, Yukio; Jinbo, Ryutaro; Ogiwara, Norio; Saido, Masahiro.

    1996-01-01

    In a composite member for use in walls of a thermonuclear reactor, if carbon fibers and boron carbide are mixed, since they are brought into contact with each other directly, boron is reacted with the carbon fibers to form boron carbide to lower thermal conductivity of the carbon fibers. Then, in the present invention, graphite or amorphous carbon is filled between the carbon fibers to provide a fiber bundle of not less than 500 carbon fibers. Further, the surface of the fiber bundle is coated with graphite or amorphous carbon to suppress diffusion or solid solubilization of boron to carbon fibers or reaction of them. Then, lowering of thermal conductivity of the carbon fibers is prevented, as well as the mixing amount of the carbon fiber bundles with boron carbide, a sintering temperature and orientation of carbon fiber bundles are optimized to provide a highly thermal conductive carbon fiber/boron carbide composite material. In addition, carbide or boride type short fibers, spherical graphite, and amorphous carbon are mixed in the boron carbide to prevent development of cracks. Diffusion or solid solubilization of boron to carbon fibers is reduced or reaction of them if the carbon fibers are bundled. (N.H.)

  12. Feasibility study of SMART core with soluble boron

    International Nuclear Information System (INIS)

    Kim, Kang Seog; Lee, Chung Chan; Zee, Sung Quun

    2000-11-01

    The excess reactivity of SMART core without soluble boron is effectively controlled by 49 CEDM. We suggest another method to control the core excess reactivity using both the checkerboard type of 25 CEDM and soluble boron and perform a feasibility calculation. The soluble boron operation is categorized into the on-line and the off-line mechanisms. The former is to successively control the boron concentration according to the excess reactivity during operation and the latter is to add and change some soluble boron during refueling and repairing. Since the on-line soluble boron control system of SMART is conceptually identical to that of the commercial pressurized water reactor, we did not perform the analysis. Since the soluble boron in the complete off-line system increases the moderator temperature coefficient, the reactivity defect between hot and cold moderator temperature is decreased. However, the decrease of the reactivity is not big to satisfy the core reactivity limits. When using 25 CEDM, the possible mechanism is to control the excess reactivity by both control rod and on-line boron control mechanism between cold and hot zero power and by only control rod at hot full power. We selected the loading pattern satisfying the requirement in the view of nuclear design

  13. Mass spectrometric investigation of vinyl-substituted organic boron compounds

    International Nuclear Information System (INIS)

    Tarielashvili, V.O.; Ordzhonikidze, K.G.; Parulava, L.P.; Vakhaniya, G.V.

    1992-01-01

    Mass spectrometric investigation of vinyl-substituted organic compounds was conducted. Ionization was performed by electron shock. Possibility of determining boron isotope content is all analyzed organic boron vinyl-substituted compounds by direct method is shown. This simplifies sufficiently and lowers the price of analysis, improves its accuracy and rapidity

  14. Determination of free and combined carbon in boron carbide

    International Nuclear Information System (INIS)

    Shankaran, P.S.; Kulkarni, Amit S.; Pandey, K.L.; Ramanjaneyulu, P.S.; Yadav, C.S.; Sayi, Y.S.; Ramakumar, K.L.

    2009-01-01

    A simple, sensitive and fast method for the determination of free and combined carbon in boron carbide samples, based on combustion in presence of oxygen at different temperatures, has been developed. Method has been standardized by analyzing mixture of two different boron carbide samples. Error associated with the method in the determination of free carbon is less than 5%. (author)

  15. The investigation of parameters affecting boron removal by electrocoagulation method

    Energy Technology Data Exchange (ETDEWEB)

    Yilmaz, A. Erdem [Department of Environmental Engineering, Atatuerk University, Faculty of Engineering, Erzurum (Turkey)]. E-mail: aerdemy@atauni.edu.tr; Boncukcuoglu, Recep [Department of Environmental Engineering, Atatuerk University, Faculty of Engineering, Erzurum (Turkey); Kocakerim, M. Muhtar [Department of Chemical Engineering, 25240, Atatuerk University, Faculty of Engineering Erzurum (Turkey); Keskinler, Buelent [Department of Environmental Engineering, Gebze Institute of Technology, Gebze/Kocaeli 41400 (Turkey)

    2005-10-17

    Boron removal from wastewaters by electrocoagulation using aluminum electrode material was investigated in this paper. Several working parameters, such as pH, current density, boron concentration and type and concentration of supporting electrolyte were studied in an attempt to achieve a higher removal capacity. The experiments were carried out by keeping the pH of solution constant and optimum pH of solution was determined 8.0 for the aluminum electrode. Although energy consumption increased with decreasing boron concentration, which conductivity of these solutions were low, boron removal efficiency was higher at 100 mg/L than that of 1000 mg/L. Current density was an important parameter affecting removal efficiency. Boron removal efficiency and energy consumption increased with increasing current density from 1.2 to 6.0 mA/cm{sup 2}. The types of different supporting electrolyte were experimented in order to investigate to this parameter effect on boron removal. The highest boron removal efficiency, 97%, was found by CaCl{sub 2}. Added CaCl{sub 2} increased more the conductivity of solution according to other supporting electrolytes, but decreased energy consumption. The results showed to have a high effectiveness of the electrocoagulation method in removing boron from aqueous solutions.

  16. The investigation of parameters affecting boron removal by electrocoagulation method

    International Nuclear Information System (INIS)

    Yilmaz, A. Erdem; Boncukcuoglu, Recep; Kocakerim, M. Muhtar; Keskinler, Buelent

    2005-01-01

    Boron removal from wastewaters by electrocoagulation using aluminum electrode material was investigated in this paper. Several working parameters, such as pH, current density, boron concentration and type and concentration of supporting electrolyte were studied in an attempt to achieve a higher removal capacity. The experiments were carried out by keeping the pH of solution constant and optimum pH of solution was determined 8.0 for the aluminum electrode. Although energy consumption increased with decreasing boron concentration, which conductivity of these solutions were low, boron removal efficiency was higher at 100 mg/L than that of 1000 mg/L. Current density was an important parameter affecting removal efficiency. Boron removal efficiency and energy consumption increased with increasing current density from 1.2 to 6.0 mA/cm 2 . The types of different supporting electrolyte were experimented in order to investigate to this parameter effect on boron removal. The highest boron removal efficiency, 97%, was found by CaCl 2 . Added CaCl 2 increased more the conductivity of solution according to other supporting electrolytes, but decreased energy consumption. The results showed to have a high effectiveness of the electrocoagulation method in removing boron from aqueous solutions

  17. Effect of boron on growth criteria of some wheat cultivars

    Directory of Open Access Journals (Sweden)

    Ashraf Metwally

    2012-01-01

    Full Text Available Introduction: Toxic soil concentrations of the essential micronutrient boron (B represent major limitations to crop production worldwide. Plants have a range of defense systems that might be involved in their affinity to resist and tolerate nutrients stress.Materials and methods: The experiments were carried out to study the differential responses in five wheat cultivars to boron toxicity. Results: The fresh and dry matter yield of the test wheat cultivars showed marked decrease as the concentration of boron was increased. Elevated concentration of boron had a notable inhibitory effect on the biosynthesis of pigments fractions in the test wheat cultivars as severely as dry matter gain. The adverse concentration effects of boron on some metabolic responses were clearly displayed by shoot and root systems, exhibited in the elevated rates of proline, hydrogen peroxide and malondialdehyde formation. Potassium leakage was severely affected by boron-stress in some cultivars at all tested concentrations, while in some others a moderate damage was manifested only at the higher boron concentrations.Conclusions: Sakha 93 out of all the different cultivars investigated was found to display the lowest sensitivity to boron-stress, while Gemmeza 9 was the most sensitive one.

  18. New applications of the interaction between diols and boronic acids

    NARCIS (Netherlands)

    Duval, F.L.

    2015-01-01

    Florine Duval - New applications of the interaction between diols and boronic acids – Summary

    Chapter 1 introduces the theory and known applications of the interaction between boronic acids and diols, and explains the context of this thesis. Diagnosis of

  19. Contamination of urban garden soils with copper and boron

    Energy Technology Data Exchange (ETDEWEB)

    Purves, D

    1966-06-04

    Spectrochemical analyses of garden soils sampled in the Edinburgh and Dundee areas indicate that there is substantial contamination of urban soils with copper and boron. These soils were analyzed spectrochemically with respect to total copper and water-extractable boron content with the view of comparing the levels obtained in urban areas with levels in arable soils in rural areas. The results indicate that urban garden soils contain about four times as much copper and two to three times as much water-soluble boron as rural arable soils. The existence of such a marked disparity between the levels of two potentially toxic elements in urban and rural areas is evidence of slow poisoning of the soil environment in built-up areas and is cause for concern. While the major source of contamination of soils with copper and boron is still a matter for speculation, it is probable that the addition of soot to garden soils and the fall-out of sooty material in built-up areas where atmospheric pollution is a problem make a substantial contribution to the water-extractable boron content of urban soils. Three samples of soot from domestic chimneys, obtained from independent sources, were found on analysis to contain 640, 650 and 555 p.p.m. water-extractable boron, and it is evident that the addition to soil of even small amounts of soot with a boron content of this order would have a marked effect on its water-extractable boron content.

  20. Preparation of boron-nitrogen films by sputtering

    International Nuclear Information System (INIS)

    Klose, S.; Winde, B.

    1980-01-01

    Hard boron-nitrogen films adherent to various substrates can be prepared by sputtering. IR investigations suggest the existence of cubic boron nitride in certain layers. Transmission electron microscope studies have shown a quasi-amorphous structure irregularly incorporating crystallites of zinc blende structure of some nm in diameter

  1. Production of boron carbide powder by carbothermal synthesis of ...

    Indian Academy of Sciences (India)

    TECS

    weight armour plates etc (Alizadeh et al 2004). It can also be used as a reinforcing material for ceramic matrix composites. It is an excellent neutron absorption material in nuclear industry due to its high neutron absorption co- efficient (Sinha et al 2002). Boron carbide can be prepared by reaction of elemental boron and ...

  2. Boron Diffusion in Surface-Treated Framing Lumber

    Science.gov (United States)

    Patricia K. Lebow; Stan T. Lebow; Steven A. Halverson

    2013-01-01

    The extent of boron penetration in framing lumber treated by spray applications during construction is not well quantified. This study evaluated the effect of formulation and concentration on diffusion of boron in lumber specimens that were equilibrated in conditions that produced wood moisture contents of 18 to 21 percent. One set of specimens was pressure treated...

  3. Design, Fabrication and Performance of Boron-Carbide Control Elements

    International Nuclear Information System (INIS)

    Brammer, H.A.; Jacobson, J.

    1964-01-01

    A control blade design, incorporating boron-carbide (B 4 C) in stainless-steel tubes, was introduced into service in boiling water reactors in April 1961. Since that time this blade has become the standard reference control element in General Electric boiling-water reactors, replacing the 2% boron-stainless-steel blades previously used. The blades consist of a sheathed, cruciform array of small vertical stainless-steel tubes filled with compácted boron-carbide powder. The boron-carbide powder is confined longitudinally into several independent compartments by swaging over ball bearings located inside the tubes. The development and use of boron-carbide control rods is discussed in five phases: 1. Summary of experience with boron-steel blades and reasons for transition to boron-carbide control; 2. Design of the boron-carbide blade, beginning with developmental experiments, including early measurements performed in the AEC ''Control Rod Material and Development Program'' at the Vallecitos Atomic Laboratory, through a description of the final control blade configuration; 3. Fabrication of the blades and quality control procedures; 4. Results of confirmatory pre-operational mechanical and reactivity testing; and 5. Post-operational experience with the blades, including information on the results of mechanical inspection and reactivity testing after two years of reactor service. (author) [fr

  4. A Modal-Logic Based Graph Abstraction

    NARCIS (Netherlands)

    Bauer, J.; Boneva, I.B.; Kurban, M.E.; Rensink, Arend; Ehrig, H; Heckel, R.; Rozenberg, G.; Taentzer, G.

    2008-01-01

    Infinite or very large state spaces often prohibit the successful verification of graph transformation systems. Abstract graph transformation is an approach that tackles this problem by abstracting graphs to abstract graphs of bounded size and by lifting application of productions to abstract

  5. Argonne Code Center: compilation of program abstracts

    Energy Technology Data Exchange (ETDEWEB)

    Butler, M.K.; DeBruler, M.; Edwards, H.S.; Harrison, C. Jr.; Hughes, C.E.; Jorgensen, R.; Legan, M.; Menozzi, T.; Ranzini, L.; Strecok, A.J.

    1977-08-01

    This publication is the eleventh supplement to, and revision of, ANL-7411. It contains additional abstracts and revisions to some earlier abstracts and other pages. Sections of the complete document ANL-7411 are as follows: preface, history and acknowledgements, abstract format, recommended program package contents, program classification guide and thesaurus, and the abstract collection. (RWR)

  6. Argonne Code Center: compilation of program abstracts

    Energy Technology Data Exchange (ETDEWEB)

    Butler, M.K.; DeBruler, M.; Edwards, H.S.

    1976-08-01

    This publication is the tenth supplement to, and revision of, ANL-7411. It contains additional abstracts and revisions to some earlier abstracts and other pages. Sections of the document are as follows: preface; history and acknowledgements; abstract format; recommended program package contents; program classification guide and thesaurus; and abstract collection. (RWR)

  7. Argonne Code Center: compilation of program abstracts

    International Nuclear Information System (INIS)

    Butler, M.K.; DeBruler, M.; Edwards, H.S.; Harrison, C. Jr.; Hughes, C.E.; Jorgensen, R.; Legan, M.; Menozzi, T.; Ranzini, L.; Strecok, A.J.

    1977-08-01

    This publication is the eleventh supplement to, and revision of, ANL-7411. It contains additional abstracts and revisions to some earlier abstracts and other pages. Sections of the complete document ANL-7411 are as follows: preface, history and acknowledgements, abstract format, recommended program package contents, program classification guide and thesaurus, and the abstract collection

  8. Argonne Code Center: compilation of program abstracts

    International Nuclear Information System (INIS)

    Butler, M.K.; DeBruler, M.; Edwards, H.S.

    1976-08-01

    This publication is the tenth supplement to, and revision of, ANL-7411. It contains additional abstracts and revisions to some earlier abstracts and other pages. Sections of the document are as follows: preface; history and acknowledgements; abstract format; recommended program package contents; program classification guide and thesaurus; and abstract collection

  9. Boron-based nanostructures: Synthesis, functionalization, and characterization

    Science.gov (United States)

    Bedasso, Eyrusalam Kifyalew

    Boron-based nanostructures have not been explored in detail; however, these structures have the potential to revolutionize many fields including electronics and biomedicine. The research discussed in this dissertation focuses on synthesis, functionalization, and characterization of boron-based zero-dimensional nanostructures (core/shell and nanoparticles) and one-dimensional nanostructures (nanorods). The first project investigates the synthesis and functionalization of boron-based core/shell nanoparticles. Two boron-containing core/shell nanoparticles, namely boron/iron oxide and boron/silica, were synthesized. Initially, boron nanoparticles with a diameter between 10-100 nm were prepared by decomposition of nido-decaborane (B10H14) followed by formation of a core/shell structure. The core/shell structures were prepared using the appropriate precursor, iron source and silica source, for the shell in the presence of boron nanoparticles. The formation of core/shell nanostructures was confirmed using high resolution TEM. Then, the core/shell nanoparticles underwent a surface modification. Boron/iron oxide core/shell nanoparticles were functionalized with oleic acid, citric acid, amine-terminated polyethylene glycol, folic acid, and dopamine, and boron/silica core/shell nanoparticles were modified with 3-(amino propyl) triethoxy silane, 3-(2-aminoethyleamino)propyltrimethoxysilane), citric acid, folic acid, amine-terminated polyethylene glycol, and O-(2-Carboxyethyl)polyethylene glycol. A UV-Vis and ATR-FTIR analysis established the success of surface modification. The cytotoxicity of water-soluble core/shell nanoparticles was studied in triple negative breast cancer cell line MDA-MB-231 and the result showed the compounds are not toxic. The second project highlights optimization of reaction conditions for the synthesis of boron nanorods. This synthesis, done via reduction of boron oxide with molten lithium, was studied to produce boron nanorods without any

  10. Problems and possibilities of development of boron nitride ceramics

    International Nuclear Information System (INIS)

    Rusanova, L.N.; Romashin, A.G.; Kulikova, G.I.; Golubeva, O.P.

    1988-01-01

    The modern state of developments in the field of technology of ceramics produced from boron nitride is analyzed. Substantial difficulties in production of pure ceramics from hexagonal and wurtzite-like boron nitride are stated as related to the structure peculiarities and inhomogeneity of chemical bonds in elementary crystal cells of various modifications. Advantages and disadvantages of familiar technological procedures in production of boron nitride ceramics are compared. A new technology is suggested, which is based on the use of electroorganic compounds for hardening and protection of porous high-purity boron-nitride die from oxidation, and as high-efficient sintered elements for treatment of powders of various structures and further pyrolisis. The method is called thermal molecular lacing (TML). Properties of ceramics produced by the TML method are compared with characteristics of well-known brands of boron nitride ceramics

  11. Fracture toughness of borides formed on boronized ductile iron

    International Nuclear Information System (INIS)

    Sen, Ugur; Sen, Saduman; Koksal, Sakip; Yilmaz, Fevzi

    2005-01-01

    In this study, fracture toughness properties of boronized ductile iron were investigated. Boronizing was realized in a salt bath consisting of borax, boric acid and ferro-silicon. Boronizing heat treatment was carried out between 850 and 950 deg. C under the atmospheric pressure for 2-8 h. Borides e.g. FeB, Fe 2 B formed on ductile iron was verified by X-ray diffraction (XRD) analysis, SEM and optical microscope. Experimental results revealed that longer boronizing time resulted in thicker boride layers. Optical microscope cross-sectional observation of borided layers showed dentricular morphology. Both microhardness and fracture toughness of borided surfaces were measured via Vickers indenter. The harnesses of borides formed on the ductile iron were in the range of 1160-2140 HV 0.1 and fracture toughness were in the range of 2.19-4.47 MPa m 1/2 depending on boronizing time and temperature

  12. An overview the boron dilution issue in PWRs

    International Nuclear Information System (INIS)

    Hyvaerinen, J.

    1994-01-01

    The presentation is an overview of boron (boric acid) dilution in pressurized water reactors (PWRs). Boric acid has been widely used in PWRs as a dissolved poison, as one of the main reactivity controlling means, for a long time, from nearly but not quite from the beginning of the design, construction and operation of PWRs in the present-day sense. The specific safety issue, namely the risk of uncontrolled reactivity insertion due to inadvertent boron dilution, is discussed first, followed by a brief look on the history of boron usage in PWRs. A discussion of boron dilution phenomenology is presented next in general terms. Some particular concerns that boron dilution phenomena arouse in the minds of a regulator will also be presented before concluding with a brief look on the future of dissolved poisons. (11 refs.)

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2006-08-14

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

  14. Boron effect on stainless steel plasticity under hot deformation

    International Nuclear Information System (INIS)

    Bulat, S.I.; Kardonov, B.A.; Sorokina, N.A.

    1978-01-01

    The effect of boron on plasticity of stainless steels at temperatures of hot deformation has been studied at three levels of alloying, i.e. 0-0.01% (micro-alloying or modifying), 0.01-0.02% (low alloying) and 0.02-2.0% (high alloying). Introduction of 0.001-0.005% of boron increases hot plasticity of both low and high carbon stainless steels due to decrease in grain size and strengthening of grain boundaries. Microalloying by boron has a positive effect at temperatures below 1200-1220 deg C. At higher temperatures, particularly when its content exceeds 0.008%, boron deteriorates plasticity by increasing the size of grains and weakening their boundaries. 0.1-2% boron strengthen the stainless steel and dectease its plasticity

  15. Impact of Boron pollution to Biota Marine aquatic

    International Nuclear Information System (INIS)

    Heni Susiati; Yarianto-SBS; Imam Hamzah; Fepriadi

    2003-01-01

    Power plants and industrial facilities can release potentially harmful chemicals, like boron through direct aqueous discharges or cycling of cooling water to aquatic ecosystems environmental at plant surrounding. Boron is an essential trace element for the growth of marine biota, but can be toxic in excessive amount. Therefore will adversely affect of growth, reproduction or survival. Toxicity to aquatic organism, including vertebrates, invertebrates and plants can vary depending on the organism's life stage and environment. It is recommended that the maximum concentration of total boron for the protection of marine aquatic life should not exceed 1,2 mg B/L. Early stages of life cycle are more sensitive to boron than later ones, and the use of reconstituted water shows higher toxicity in lower boron concentrations than natural waters. (author)

  16. Additive Manufacturing of Dense Hexagonal Boron Nitride Objects

    Energy Technology Data Exchange (ETDEWEB)

    Marquez Rossy, Andres E [ORNL; Armstrong, Beth L [ORNL; Elliott, Amy M [ORNL; Lara-Curzio, Edgar [ORNL

    2017-05-12

    The feasibility of manufacturing hexagonal boron nitride objects via additive manufacturing techniques was investigated. It was demonstrated that it is possible to hot-extrude thermoplastic filaments containing uniformly distributed boron nitride particles with a volume concentration as high as 60% and that these thermoplastic filaments can be used as feedstock for 3D-printing objects using a fused deposition system. Objects 3D-printed by fused deposition were subsequently sintered at high temperature to obtain dense ceramic products. In a parallel study the behavior of hexagonal boron nitride in aqueous solutions was investigated. It was shown that the addition of a cationic dispersant to an azeotrope enabled the formulation of slurries with a volume concentration of boron nitride as high as 33%. Although these slurries exhibited complex rheological behavior, the results from this study are encouraging and provide a pathway for manufacturing hexagonal boron nitride objects via robocasting.

  17. Boron determination in tourmaline by neutron induced radiography

    Energy Technology Data Exchange (ETDEWEB)

    Qureshi, A.A. E-mail: aaqureshi@pinstech.org.pk; Akram, M.; Ayub Khan, M.; Khattak, N.U.; Qureshi, I.E.; Khan, H.A

    2001-06-01

    The technique of neutron induced radiography has been applied to determine the boron concentration and its spatial distribution in mineral tourmaline collected from Swat Tourmaline Granite, Northern Pakistan. The technique involves the simultaneous irradiation of sample and a standard fixed on a track detector with thermal neutrons and the counting of alpha and {sup 7}Li tracks produced in the detector from the nuclear reaction {sup 10}B(n,{alpha}){sup 7}Li. Boron concentration is determined by comparing the {sup 7}Li and alpha particle tracks density with that of a standard of known boron concentration. Boron concentration in tourmaline has been found to be (3.40{+-}0.01)% in this study which is on the upper side within the normal range (2.5-3.8)% reported in the world. The presence of somewhat higher concentration of boron in tourmaline indicates that the Swat Tourmaline Granite was generated as a late stage hydrothermal activity during the Himalayan Orogeny.

  18. An abstract approach to music.

    Energy Technology Data Exchange (ETDEWEB)

    Kaper, H. G.; Tipei, S.

    1999-04-19

    In this article we have outlined a formal framework for an abstract approach to music and music composition. The model is formulated in terms of objects that have attributes, obey relationships, and are subject to certain well-defined operations. The motivation for this approach uses traditional terms and concepts of music theory, but the approach itself is formal and uses the language of mathematics. The universal object is an audio wave; partials, sounds, and compositions are special objects, which are placed in a hierarchical order based on time scales. The objects have both static and dynamic attributes. When we realize a composition, we assign values to each of its attributes: a (scalar) value to a static attribute, an envelope and a size to a dynamic attribute. A composition is then a trajectory in the space of aural events, and the complex audio wave is its formal representation. Sounds are fibers in the space of aural events, from which the composer weaves the trajectory of a composition. Each sound object in turn is made up of partials, which are the elementary building blocks of any music composition. The partials evolve on the fastest time scale in the hierarchy of partials, sounds, and compositions. The ideas outlined in this article are being implemented in a digital instrument for additive sound synthesis and in software for music composition. A demonstration of some preliminary results has been submitted by the authors for presentation at the conference.

  19. 1986 annual information meeting. Abstracts

    International Nuclear Information System (INIS)

    1986-01-01

    Abstracts are presented for the following papers: Geohydrological Research at the Y-12 Plant (C.S. Haase); Ecological Impacts of Waste Disposal Operations in Bear Creek Valley Near the Y-12 Plant (J.M. Loar); Finite Element Simulation of Subsurface Contaminant Transport: Logistic Difficulties in Handling Large Field Problems (G.T. Yeh); Dynamic Compaction of a Radioactive Waste Burial Trench (B.P. Spalding); Comparative Evaluation of Potential Sites for a High-Level Radioactive Waste Repository (E.D. Smith); Changing Priorities in Environmental Assessment and Environmental Compliance (R.M. Reed); Ecology, Ecotoxicology, and Ecological Risk Assessment (L.W. Barnthouse); Theory and Practice in Uncertainty Analysis from Ten Years of Practice (R.H. Gardner); Modeling Landscape Effects of Forest Decline (V.H. Dale); Soil Nitrogen and the Global Carbon Cycle (W.M. Post); Maximizing Wood Energy Production in Short-Rotation Plantations: Effect of Initial Spacing and Rotation Length (L.L. Wright); and Ecological Communities and Processes in Woodland Streams Exhibit Both Direct and Indirect Effects of Acidification (J.W. Elwood)

  20. Handedness shapes children's abstract concepts.

    Science.gov (United States)

    Casasanto, Daniel; Henetz, Tania

    2012-03-01

    Can children's handedness influence how they represent abstract concepts like kindness and intelligence? Here we show that from an early age, right-handers associate rightward space more strongly with positive ideas and leftward space with negative ideas, but the opposite is true for left-handers. In one experiment, children indicated where on a diagram a preferred toy and a dispreferred toy should go. Right-handers tended to assign the preferred toy to a box on the right and the dispreferred toy to a box on the left. Left-handers showed the opposite pattern. In a second experiment, children judged which of two cartoon animals looked smarter (or dumber) or nicer (or meaner). Right-handers attributed more positive qualities to animals on the right, but left-handers to animals on the left. These contrasting associations between space and valence cannot be explained by exposure to language or cultural conventions, which consistently link right with good. Rather, right- and left-handers implicitly associated positive valence more strongly with the side of space on which they can act more fluently with their dominant hands. Results support the body-specificity hypothesis (Casasanto, 2009), showing that children with different kinds of bodies think differently in corresponding ways. Copyright © 2011 Cognitive Science Society, Inc.

  1. WD1145+017 (Abstract)

    Science.gov (United States)

    Motta, M.

    2017-12-01

    (Abstract only) WD1145 is a 17th magnitude white dwarf star 570 light years away in Virgo that was discovered to have a disintegrating planetoid in close orbit by Andrew Vanderburg, a graduate student at Harvard CfA, while data mining the elucidate the nature of its rather bizarre transit light curves. I obtained multiple observations of WD1145 over the course of a year, and found a series of complex transit light curves that could only be interpreted as a ring complex or torus in close orbit around WD1145. Combined with data from other amateur astronomers, professional observations, and satellite data, it became clear that WD1145 has a small planetoid in close orbit at the Roche limit and is breaking apart, forming a ring of debris material that is then raining down on the white dwarf. The surface of the star is "polluted" by heavy metals, determined by spectroscopic data. Given that in the intense gravitational field of a white dwarf any heavy metals could not for long last on the surface, this confirms that we are tracking in real time the destruction of a small planet by its host star.

  2. EURORIB 2010, Book of abstracts

    International Nuclear Information System (INIS)

    Tsoneva, N.; Lenske, H.; Casten, R.

    2012-01-01

    The second international EURORIB conference 'EURORIB'10' will be held from June 6. to June 11. 2010 in Lamoura (France). Our nuclear physics community is eagerly awaiting the construction of the next generation of Radioactive Ion Beam (RIB) facilities in Europe: HIE-ISOLDE at CERN, NUSTAR at FAIR, SPES at LNL, SPIRAL2 at GANIL and the future EURISOL. The collaborations built around these facilities are exploring new experimental and theoretical ideas that will advance our understanding of nuclear structure through studies of exotic nuclei. Following in the spirit of the conference held in Giens in 2008, EURORIB'10 will provide the opportunity for the different collaborations to come together and present these ideas, and explore the synergy between the research programmes based around the hypothetical severe acprojects. The main topics to be discussed at the conference are: 1) At and beyond the drip line, 2) Shell structure far from stability, 3) Fusion reactions and synthesis of heavy and superheavy nuclei, 4) Dynamics and thermodynamics of exotic nuclear systems, 5) Radioactive ion beams in nuclear astrophysics, 6) New modes of radioactivity, 7) Fundamental interactions, 8) Applications in other fields, 9) Future RIB facilities, 10) Production and manipulation of RIB, and 11) Working group meetings on synergy in instrumentation and data acquisition. This document gathers only the abstracts of the papers. (authors)

  3. Attracting Girls into Physics (abstract)

    Science.gov (United States)

    Gadalla, Afaf

    2009-04-01

    A recent international study of women in physics showed that enrollment in physics and science is declining for both males and females and that women are severely underrepresented in careers requiring a strong physics background. The gender gap begins early in the pipeline, from the first grade. Girls are treated differently than boys at home and in society in ways that often hinder their chances for success. They have fewer freedoms, are discouraged from accessing resources or being adventurous, have far less exposure to problem solving, and are not encouraged to choose their lives. In order to motivate more girl students to study physics in the Assiut governorate of Egypt, the Assiut Alliance for the Women and Assiut Education District collaborated in renovating the education of physics in middle and secondary school classrooms. A program that helps in increasing the number of girls in science and physics has been designed in which informal groupings are organized at middle and secondary schools to involve girls in the training and experiences needed to attract and encourage girls to learn physics. During implementation of the program at some schools, girls, because they had not been trained in problem-solving as boys, appeared not to be as facile in abstracting the ideas of physics, and that was the primary reason for girls dropping out of science and physics. This could be overcome by holding a topical physics and technology summer school under the supervision of the Assiut Alliance for the Women.

  4. The triconnected abstraction of process models

    OpenAIRE

    Polyvyanyy, Artem; Smirnov, Sergey; Weske, Mathias

    2009-01-01

    Contents: Artem Polyvanny, Sergey Smirnow, and Mathias Weske The Triconnected Abstraction of Process Models 1 Introduction 2 Business Process Model Abstraction 3 Preliminaries 4 Triconnected Decomposition 4.1 Basic Approach for Process Component Discovery 4.2 SPQR-Tree Decomposition 4.3 SPQR-Tree Fragments in the Context of Process Models 5 Triconnected Abstraction 5.1 Abstraction Rules 5.2 Abstraction Algorithm 6 Related Work and Conclusions

  5. Neosporosis in South America.

    Science.gov (United States)

    Moore, D P

    2005-01-20

    This work gathers reports about Neospora-infections in South America. Neospora-infections have been reported from Argentina, Brazil, Chile, Paraguay, Peru and Uruguay. Evidence of exposure to N. caninum was mentioned in cattle, goats, sheep, dogs, cats, water buffaloes, alpacas, llamas, South American opossums, wolves and other wild canids. No antibodies were found in horses. Interesting epidemiological and pathological data were described. Two isolations were performed from dogs, one from cattle, and recently five from water buffaloes. Since the cattle industry is important in South America and reproductive losses caused by Neospora-infection have been identified, more investigations are needed in order to understand its epidemiology and control the disease.

  6. Numerical simulation of boron injection in a BWR

    Energy Technology Data Exchange (ETDEWEB)

    Tinoco, Hernan, E-mail: htb@forsmark.vattenfall.s [Forsmarks Kraftgrupp AB, SE-742 03 Osthammar (Sweden); Buchwald, Przemyslaw [Reactor Technology, Royal Institute of Technology, SE-100 44 Stockholm (Sweden); Frid, Wiktor, E-mail: wiktor@reactor.sci.kth.s [Reactor Technology, Royal Institute of Technology, SE-100 44 Stockholm (Sweden)

    2010-02-15

    The present study constitutes a first step to understand the process of boron injection, transport and mixing in a BWR. It consists of transient CFD simulations of boron injection in a model of the downcomer of Forsmark's Unit 3 containing about 6 million elements. The two cases studied are unintentional start of boron injection under normal operation and loss of offsite power with partial ATWS leaving 10% of the core power uncontrolled. The flow conditions of the second case are defined by means of an analysis with RELAP5, assuming boron injection start directly after the first ECCS injection. Recent publications show that meaningful conservative results may be obtained for boron or thermal mixing in PWRs with grids as coarse as that utilized here, provided that higher order discretization schemes are used to minimize numerical diffusion. The obtained results indicate an apparently strong influence of the scenario in the behavior of the injection process. The normal operation simulation shows that virtually all boron solution flows down to the Main Recirculation Pump inlet located directly below the boron inlet nozzle. The loss of offsite power simulation shows initially a spread of the boron solution over the entire sectional area of the lower part of the downcomer filled with colder water. This remaining effect of the ECCS injection lasts until all this water has left the downcomer. Above this region, the boron injection jet develops in a vertical streak, eventually resembling the injection of the normal operation scenario. Due to the initial spread, this boron injection will probably cause larger temporal and spatial concentration variations in the core. In both cases, these variations may cause reactivity transients and fuel damage due to local power escalation. To settle this issue, an analysis using an extended model containing the downcomer, the MRPs and the Lower Plenum will be carried out. Also, the simulation time will be extended to a scale of

  7. Numerical simulation of boron injection in a BWR

    International Nuclear Information System (INIS)

    Tinoco, Hernan; Buchwald, Przemyslaw; Frid, Wiktor

    2010-01-01

    The present study constitutes a first step to understand the process of boron injection, transport and mixing in a BWR. It consists of transient CFD simulations of boron injection in a model of the downcomer of Forsmark's Unit 3 containing about 6 million elements. The two cases studied are unintentional start of boron injection under normal operation and loss of offsite power with partial ATWS leaving 10% of the core power uncontrolled. The flow conditions of the second case are defined by means of an analysis with RELAP5, assuming boron injection start directly after the first ECCS injection. Recent publications show that meaningful conservative results may be obtained for boron or thermal mixing in PWRs with grids as coarse as that utilized here, provided that higher order discretization schemes are used to minimize numerical diffusion. The obtained results indicate an apparently strong influence of the scenario in the behavior of the injection process. The normal operation simulation shows that virtually all boron solution flows down to the Main Recirculation Pump inlet located directly below the boron inlet nozzle. The loss of offsite power simulation shows initially a spread of the boron solution over the entire sectional area of the lower part of the downcomer filled with colder water. This remaining effect of the ECCS injection lasts until all this water has left the downcomer. Above this region, the boron injection jet develops in a vertical streak, eventually resembling the injection of the normal operation scenario. Due to the initial spread, this boron injection will probably cause larger temporal and spatial concentration variations in the core. In both cases, these variations may cause reactivity transients and fuel damage due to local power escalation. To settle this issue, an analysis using an extended model containing the downcomer, the MRPs and the Lower Plenum will be carried out. Also, the simulation time will be extended to a scale of several

  8. Packing C60 in Boron Nitride Nanotubes

    Science.gov (United States)

    Mickelson, W.; Aloni, S.; Han, Wei-Qiang; Cumings, John; Zettl, A.

    2003-04-01

    We have created insulated C60 nanowire by packing C60 molecules into the interior of insulating boron nitride nanotubes (BNNTs). For small-diameter BNNTs, the wire consists of a linear chain of C60 molecules. With increasing BNNT inner diameter, unusual C60 stacking configurations are obtained (including helical, hollow core, and incommensurate) that are unknown for bulk or thin-film forms of C60. C60 in BNNTs thus presents a model system for studying the properties of dimensionally constrained ``silo'' crystal structures. For the linear-chain case, we have fused the C60 molecules to form a single-walled carbon nanotube inside the insulating BNNT.

  9. Stability analysis of zigzag boron nitride nanoribbons

    Energy Technology Data Exchange (ETDEWEB)

    Rai, Hari Mohan, E-mail: rai.2208@gmail.com; Late, Ravikiran; Saxena, Shailendra K.; Kumar, Rajesh; Sagdeo, Pankaj R. [Indian Institute of Technology, Indore –452017 (India); Jaiswal, Neeraj K. [Discipline of Physics, PDPM- Indian Institute of Information Technology, Design and Manufacturing, Jabalpur – 482005 (India); Srivastava, Pankaj [Computational Nanoscience and Technology Lab. (CNTL), ABV- Indian Institute of Information Technology and Management, Gwalior – 474015 (India)

    2015-05-15

    We have explored the structural stability of bare and hydrogenated zigzag boron nitride nanoribbons (ZBNNRs). In order to investigate the structural stability, we calculate the cohesive energy for bare, one-edge and both edges H-terminated ZBNNRs with different widths. It is found that the ZBNNRs with width Nz=8 are energetically more favorable than the lower-width counterparts (Nz<8). Bare ZBNNRs have been found energetically most stable as compared to the edge terminated ribbons. Our analysis reveals that the structural stability is a function of ribbon-width and it is not affected significantly by the type of edge-passivation (one-edge or both-edges)

  10. Magnesium doping of boron nitride nanotubes

    Science.gov (United States)

    Legg, Robert; Jordan, Kevin

    2015-06-16

    A method to fabricate boron nitride nanotubes incorporating magnesium diboride in their structure. In a first embodiment, magnesium wire is introduced into a reaction feed bundle during a BNNT fabrication process. In a second embodiment, magnesium in powder form is mixed into a nitrogen gas flow during the BNNT fabrication process. MgB.sub.2 yarn may be used for superconducting applications and, in that capacity, has considerably less susceptibility to stress and has considerably better thermal conductivity than these conventional materials when compared to both conventional low and high temperature superconducting materials.

  11. Synthesis of boron-containing heterocyclic compounds

    International Nuclear Information System (INIS)

    Azev, Yuri; Slepukhina, Irina; Gabel, Detlef

    2004-01-01

    The synthesis of boron-containing 1,3,5-triazines and 1,2,4-triazines is described. Derivatives of 1,3,5-triazine containing the o-carborane cluster have been obtained by reacting the corresponding propargyl derivatives with B 10 H 14 . Derivatives of 1,2,4-triazine containing the B 12 H 12 2- cluster have been obtained by nucleophilic substitution of ethylsulfone derivatives with B 12 H 11 SH 2- . They have been isolated in their ring-protonated form. Reaction of RNH 2 -B 8 H 11 NH-R with stericly demanding heterocycles failed, either for steric or for solubility reasons

  12. Salinity’s influence on boron toxicity in broccoli: II. Impacts on boron uptake, uptake mechanisms and tissue ion relations.

    Science.gov (United States)

    Limited research has been conducted on the interactive effects of salinity and boron stresses on plants despite their common occurrence in natural systems. The purpose of this research was to determine and quantify the interactive effects of salinity, salt composition and boron on broccoli (Brassica...

  13. Continued biological investigations of boron-rich oligomeric phosphate diesters (OPDs). Tumor-selective boron agents for BNCT

    International Nuclear Information System (INIS)

    Lee, Mark W.; Shelly, Kenneth; Kane, Robert R.; Hawthorne, M. Frederick

    2006-01-01

    Clinical success of Boron Neutron Capture Therapy will rely on the selective intracellular delivery of high concentrations of boron-10 to tumor tissue. In order for a boron agent to facilitate clinical success, the simultaneous needs of obtaining a high tumor dose, high tumor selectivity, and low systemic toxicity must be realized. Boron-rich oligomeric phosphate diesters (OPDs) are a class of highly water-soluble compounds containing up to 40% boron by weight. Previous work in our groups demonstrated that once placed in the cytoplasm of tumor cells, OPDs quickly accumulate within the cell nucleus. The objective of the current study was to determine the biodistribution of seven different free OPDs in BALB/c mice bearing EMT6 tumors. Fructose solutions containing between 1.4 and 6.4 micrograms of boron per gram of tissue were interveinously injected in mice seven to ten days after tumor implantation. At intervals during the study, animals were euthanized and samples of tumor, blood, liver, kidney, brain and skin were collected and analyzed for boron content using ICP-AES. Tumor boron concentrations of between 5 and 29 ppm were achieved and maintained over the 72-hour time course of each experiment. Several OPDs demonstrated high tumor selectivity with one oligomer exhibiting a tumor to blood ratio of 35:1. The apparent toxicity of each oligomer was assessed through animal behavior during the experiment and necropsy of each animal upon sacrifice. (author)

  14. Meeting the challenge of homogenous boron targeting of heterogeneous tumors for effective boron neutron capture therapy (BNCT)

    International Nuclear Information System (INIS)

    Heber, Elisa M.; Trivillin, Veronica A.; Itoiz, Maria E.; Rebagliati, J. Raul; Batistoni, Daniel; Kreimann, Erica L.; Schwint, Amanda E.; Nigg, David W.; Gonzalez, Beatriz N.

    2006-01-01

    BNCT is a tumor cell targeted radiation therapy. Inadequately boron targeted tumor populations jeopardize tumor control. Meeting the to date unresolved challenge of homogeneous targeting of heterogeneous tumors with effective boron carriers would contribute to therapeutic efficacy. The aim of the present study was to evaluate the degree of variation in boron content delivered by boronophenylalanine (BPA), GB-10 (Na 2 10 B 10 H 10 ) and the combined administration of (BPA+GB-10) in different portions of tumor, precancerous tissue around tumor and normal pouch tissue in the hamster cheek pouch oral cancer model. Boron content was evaluated by ICP-AES. The degree of homogeneity in boron targeting was assessed in terms of the coefficient of variation ([S.D./Mean]x100) of boron values. Statistical analysis of the results was performed by one-way ANOVA and the least significant difference test. GB-10 and GB-10 plus BPA achieved respectively a statistically significant 1.8-fold and 3.3-fold increase in targeting homogeneity over BPA. The combined boron compound administration protocol contributes to homogeneous targeting of heterogeneous tumors and would increase therapeutic efficacy of BNCT by exposing all tumor populations to neutron capture reactions in boron. (author)

  15. Strategy for designing stable and powerful nitrogen-rich high-energy materials by introducing boron atoms.

    Science.gov (United States)

    Wu, Wen-Jie; Chi, Wei-Jie; Li, Quan-Song; Li, Ze-Sheng

    2017-06-01

    One of the most important aims in the development of high-energy materials is to improve their stability and thus ensure that they are safe to manufacture and transport. In this work, we theoretically investigated open-chain N 4 B 2 isomers using density functional theory in order to find the best way of stabilizing nitrogen-rich molecules. The results show that the boron atoms in these isomers are aligned linearly with their neighboring atoms, which facilitates close packing in the crystals of these materials. Upon comparing the energies of nine N 4 B 2 isomers, we found that the structure with alternating N and B atoms had the lowest energy. Structures with more than one nitrogen atom between two boron atoms had higher energies. The energy of N 4 B 2 increases by about 50 kcal/mol each time it is rearranged to include an extra nitrogen atom between the two boron atoms. More importantly, our results also show that boron atoms stabilize nitrogen-rich molecules more efficiently than carbon atoms do. Also, the combustion of any isomer of N 4 B 2 releases more heat than the corresponding isomer of N 4 C 2 does under well-oxygenated conditions. Our study suggests that the three most stable N 4 B 2 isomers (BN13, BN24, and BN34) are good candidates for high-energy molecules, and it outlines a new strategy for designing stable boron-containing high-energy materials. Graphical abstract The structural characteristics, thermodynamic stabilities, and exothermic properties of nitrogen-rich N 4 B 2 isomers were investigated by means of density functional theory.

  16. SOIL AND WATER CONSERVATION POLICY APPROACHES IN NORTH AMERICA, EUROPE, AND AUSTRALIA. (R825761)

    Science.gov (United States)

    AbstractSoil and water conservation policies and programs in developed countries in North America, Europe, and Australia are examined in the context of their effectiveness for addressing environmental degradation associated with technology-intensive agricultural syste...

  17. Daymet: Daily Surface Weather Data on a 1-km Grid for North America, Version 2

    Data.gov (United States)

    National Aeronautics and Space Administration — ABSTRACT: This data set provides Daymet output data as mosaicked gridded estimates of daily weather parameters for North America, including daily continuous surfaces...

  18. The Aggregation of Boron on the Tissues of Gold Fish (Carassius auratus Linnaeus, 1758

    Directory of Open Access Journals (Sweden)

    Tuncer Okan Genç

    2015-03-01

    Full Text Available In this study, it was aimed to determine the water-borne and food-borne boron accumulation in the liver and muscle tissues of Gold Fish (Carassius auratus Linnaeus, 1758. For each treatment, 12 individuals were. The water-borne boron treatments were applied as boron acid concentration of 1 mg/L, 10 mg/L and 20 mg/L in the aquarium water, while the food-borne boron treatments were prepared food contained the defined levels of boron (1 mg/kg, 5 mg/kg and 10 mg/kg as boric acid. The boron levels in the tissues were determined by an ICP-MS procedure. The maximum boron concentration was found in the 20mg/L water borne boron treatment in the liver tissue (1.78±0.02 mg/kg. In the water-borne boron treatments, the maximum Transfer Factor (TF was found in the 20mg/L boron concentration, and TF values were increased when the boron concentrations were decreasing. In the 1 mg/kg food-borne boron treatment, TF was found as 0, and increasing concentration of boron in the food caused an increase in TF reached about 0.06. This study suggested that the target organ for boron accumulation is the liver rather than the muscles and the accumulation of food-borne boron is lower when comparing water-borne boron.

  19. Exploiting the enantioselectivity of Baeyer-Villiger monooxygenases via boron oxidation

    NARCIS (Netherlands)

    Brondani, Patricia B.; Dudek, Hanna; Reis, Joel S.; Fraaije, Marco W.; Andrade, Leandro H.

    2012-01-01

    The enantioselective carbon-boron bond oxidation of several chiral boron-containing compounds by Baeyer-Villiger monooxygenases was evaluated. PAMO and M446G PAMO conveniently oxidized 1-phenylethyl boronate into the corresponding 1-(phenyl)ethanol (ee = 82-91%). Cyclopropyl boronic esters were also

  20. Study of the boron distribution in pea and alfalfa plants using SSNTD

    International Nuclear Information System (INIS)

    Li Jianming; Inst. for Application of Atomic Energy)" data-affiliation=" (Chinese Academy of Agricultural Sciences, Beijing, BJ (China)> Inst. for Application of Atomic Energy)" >Deng Hongmin

    1988-01-01

    The distribution of boron in pea (Pisum sativum L.) and alfalfa (Medicago sativa L.) was determined by using SSNTD. The results show that boron concentrations in leaves are highest, furthermore boron concentrations of the base leaves are higher than those of the top leaves. Among flower tissues, calyx has the highest boron concentration