WorldWideScience

Sample records for investigation phase sdm-site

  1. Site description of Forsmark at completion of the site investigation phase. SDM-Site Forsmark

    International Nuclear Information System (INIS)

    2008-12-01

    The Swedish Nuclear Fuel and Waste Management Co., SKB, has undertaken site characterisation in two different areas, Forsmark and Laxemar-Simpevarp, in order to identify a suitable location for a geological repository of spent nuclear fuel according to the KBS-3 method. The site investigations have been conducted in campaigns, punctuated by data freezes. After each data freeze, the site data have been analysed and modelling has been carried out with the overall purpose to develop a site descriptive model (SDM). The site descriptive model is used by repository engineering to design the underground facility and to develop a repository layout adapted to the site. It is also essential for safety assessment, since the model is the only source for site-specific input. Another important use of the site descriptive model is in the environmental impact assessment. An SDM is an integrated model for geology, thermal properties, rock mechanics, hydrogeology, hydrogeochemistry, bedrock transport properties and a description of the surface system. The site descriptive model compiled in the current report, SDM-Site, presents an integrated understanding of the Forsmark area at the completion of the surface-based investigations, which were conducted at Forsmark during the period 2002 to 2007. It also provides a summary of the abundant underlying data and the discipline-specific models that support the site understanding. The description relies heavily on background reports that address, in particular, details in data analyses and modelling in the different disciplines. The Forsmark area is located in northern Uppland within the municipality of Oesthammar, about 120 km north of Stockholm. The candidate area for site investigation is located along the shoreline of Oeregrundsgrepen, within the north-western part of a major tectonic lens that formed between 1.87 and 1.85 billion years ago during the Svecokarelian orogeny. The candidate area is approximately 6 km long and 2 km wide. The

  2. Site description of Forsmark at completion of the site investigation phase. SDM-Site Forsmark

    Energy Technology Data Exchange (ETDEWEB)

    2008-12-15

    The Swedish Nuclear Fuel and Waste Management Co., SKB, has undertaken site characterisation in two different areas, Forsmark and Laxemar-Simpevarp, in order to identify a suitable location for a geological repository of spent nuclear fuel according to the KBS-3 method. The site investigations have been conducted in campaigns, punctuated by data freezes. After each data freeze, the site data have been analysed and modelling has been carried out with the overall purpose to develop a site descriptive model (SDM). The site descriptive model is used by repository engineering to design the underground facility and to develop a repository layout adapted to the site. It is also essential for safety assessment, since the model is the only source for site-specific input. Another important use of the site descriptive model is in the environmental impact assessment. An SDM is an integrated model for geology, thermal properties, rock mechanics, hydrogeology, hydrogeochemistry, bedrock transport properties and a description of the surface system. The site descriptive model compiled in the current report, SDM-Site, presents an integrated understanding of the Forsmark area at the completion of the surface-based investigations, which were conducted at Forsmark during the period 2002 to 2007. It also provides a summary of the abundant underlying data and the discipline-specific models that support the site understanding. The description relies heavily on background reports that address, in particular, details in data analyses and modelling in the different disciplines. The Forsmark area is located in northern Uppland within the municipality of Oesthammar, about 120 km north of Stockholm. The candidate area for site investigation is located along the shoreline of Oeregrundsgrepen, within the north-western part of a major tectonic lens that formed between 1.87 and 1.85 billion years ago during the Svecokarelian orogeny. The candidate area is approximately 6 km long and 2 km wide. The

  3. Site description of Laxemar at completion of the site investigation phase. SDM-Site Laxemar

    Energy Technology Data Exchange (ETDEWEB)

    2009-12-15

    The Swedish Nuclear Fuel and Waste Management Company (SKB) has undertaken site characterisation in two different areas, Forsmark and Laxemar-Simpevarp, in order to identify a suitable location for a geological repository of spent nuclear fuel according to the KBS-3 method. The site investigations have been conducted in campaigns, punctuated by data freezes. After each data freeze, the site data have been analysed and modelling has been carried out with the overall purpose to develop a site descriptive model (SDM). The site descriptive model is used by repository engineering to design the underground facility and to develop a repository layout adapted to the site. It is also essential for safety assessment, since the SDM is the only source for site-specific input. Another important use of the site descriptive model is in the environmental impact assessment. An SDM is an integrated model of geology, thermal properties, rock mechanics, hydrogeology, hydrogeochemistry, bedrock transport properties and a description of the surface system. The site descriptive model compiled in the current report, SDM-Site Laxemar, presents an integrated understanding of the Laxemar-Simpevarp area (with special emphasis on the Laxemar subarea) at the completion of the surface-based investigations, which were conducted during the period 2002 to 2007. A summary is also provided of the abundant underlying data and the discipline specific models that support the site understanding. The description relies heavily on background reports that address, in particular, details of the data analyses and modelling of the different disciplines. The Laxemar-Simpevarp area is located in the province of Smaaland within the municipality of Oskarshamn, about 230 km south of Stockholm. The candidate area for site investigation is located along the shoreline of the strait of Kalmarsund, within a 1.8 billion year old suite of well preserved bedrock belonging to the Transscandinavian Igneous Belt formed during

  4. Site description of Laxemar at completion of the site investigation phase. SDM-Site Laxemar

    International Nuclear Information System (INIS)

    2009-12-01

    The Swedish Nuclear Fuel and Waste Management Company (SKB) has undertaken site characterisation in two different areas, Forsmark and Laxemar-Simpevarp, in order to identify a suitable location for a geological repository of spent nuclear fuel according to the KBS-3 method. The site investigations have been conducted in campaigns, punctuated by data freezes. After each data freeze, the site data have been analysed and modelling has been carried out with the overall purpose to develop a site descriptive model (SDM). The site descriptive model is used by repository engineering to design the underground facility and to develop a repository layout adapted to the site. It is also essential for safety assessment, since the SDM is the only source for site-specific input. Another important use of the site descriptive model is in the environmental impact assessment. An SDM is an integrated model of geology, thermal properties, rock mechanics, hydrogeology, hydrogeochemistry, bedrock transport properties and a description of the surface system. The site descriptive model compiled in the current report, SDM-Site Laxemar, presents an integrated understanding of the Laxemar-Simpevarp area (with special emphasis on the Laxemar subarea) at the completion of the surface-based investigations, which were conducted during the period 2002 to 2007. A summary is also provided of the abundant underlying data and the discipline specific models that support the site understanding. The description relies heavily on background reports that address, in particular, details of the data analyses and modelling of the different disciplines. The Laxemar-Simpevarp area is located in the province of Smaaland within the municipality of Oskarshamn, about 230 km south of Stockholm. The candidate area for site investigation is located along the shoreline of the strait of Kalmarsund, within a 1.8 billion year old suite of well preserved bedrock belonging to the Transscandinavian Igneous Belt formed during

  5. Bedrock hydrogeology Forsmark. Site descriptive modelling, SDM-Site Forsmark

    International Nuclear Information System (INIS)

    Follin, Sven

    2008-12-01

    The Swedish Nuclear Fuel and Waste Management Company (SKB) has conducted site investigations at two different locations, the Forsmark and Laxemar-Simpevarp areas, with the objective of siting a final repository for spent nuclear fuel according to the KBS-3 concept. Site characterisation should provide all data required for an integrated evaluation of the suitability of the investigated site and an important component in the characterisation work is the development of a hydrogeological model. The hydrogeological model is used by repository engineering to design the underground facility and to develop a repository layout adapted to the site. It also provides input to the safety assessment. Another important use of the hydrogeological model is in the environmental impact assessment. This report presents the understanding of the hydrogeological conditions of the bedrock at Forsmark reached following the completion of the surface-based investigations and provides a summary of the bedrock hydrogeological model and the underlying data supporting its development. It constitutes the main reference on bedrock hydrogeology for the site descriptive model concluding the surface-based investigations at Forsmark, SDM-site, and is intended to describe the hydraulic properties and hydrogeological conditions of the bedrock at the site and to give the information essential for demonstrating understanding

  6. Geology Laxemar. Site descriptive modelling SDM-Site Laxemar

    Energy Technology Data Exchange (ETDEWEB)

    Wahlgren, Carl-Henric (Geological Survey of Sweden, Uppsala (Sweden)); Curtis, Philip; Hermanson, Jan; Forssberg, Ola; Oehman, Johan (Golder Associates AB (Sweden)); Fox, Aaron; La Pointe, Paul (Golder Associates Inc (United States)); Drake, Henrik (Dept. of Earth Sciences, Univ. of Goeteborg, Goeteborg (Sweden)); Triumf, Carl-Axel; Mattsson, Haakan; Thunehed, Hans (GeoVista AB, Luleaa (Sweden)); Juhlin, Christopher (Dept. of Earth Sciences, Uppsala Univ., Uppsala (Sweden))

    2008-11-15

    The geological work during the SDM Site Laxemar modelling stage has involved the continued development of deterministic models for rock domains (RSM) and deformation zones (ZSM), the identification and deterministic modelling of fracture domains (FSM), and the development of statistical models for fractures and minor deformation zones (geological discrete fracture network (DFN) modelling). The geological DFN model addresses fractures/structures with a size of less than 1 km, which is the lower cut-off of structures included in the deterministic modelling of deformation zones. In order to take account of variability in data resolution, deterministic models for rock domains and deformation zones are presented in both regional and local scale model volumes, while the geological DFN model is valid only within specific fracture domains inside the Laxemar local model volume. The geological and geophysical data that constitute the basis for the SDM-Site Laxemar modelling work comprise all data that have been acquired from Laxemar, i.e. all data that were available at the data freeze for SDM-Site Laxemar at August 31, 2007. Selected quality controlled data from the complementary cored borehole KLX27A have also been utilised in the modelling work. Data from the following investigations were acquired during the complete site investigation between the data freezes for Laxemar 1.2 and SDM-Site Laxemar as defined above: A revised bedrock geological map at the ground surface. Geological and geophysical data from 40 new cored boreholes and 14 percussion boreholes. Sampling and subsequent modal and geochemical analytical work of bedrock samples taken in connection with excavations in southern Laxemar. Detailed mapping of fractures and rock units along 10 trench excavations and 2 large surface exposures (drill sites for KLX09 and KLX11A/KLX20A). Special studies involving more detailed characterisation of deformation zones identified in the geological single-hole interpretation

  7. Geology Laxemar. Site descriptive modelling SDM-Site Laxemar

    International Nuclear Information System (INIS)

    Wahlgren, Carl-Henric; Curtis, Philip; Hermanson, Jan; Forssberg, Ola; Oehman, Johan; Fox, Aaron; La Pointe, Paul; Drake, Henrik; Triumf, Carl-Axel; Mattsson, Haakan; Thunehed, Hans; Juhlin, Christopher

    2008-11-01

    The geological work during the SDM Site Laxemar modelling stage has involved the continued development of deterministic models for rock domains (RSM) and deformation zones (ZSM), the identification and deterministic modelling of fracture domains (FSM), and the development of statistical models for fractures and minor deformation zones (geological discrete fracture network (DFN) modelling). The geological DFN model addresses fractures/structures with a size of less than 1 km, which is the lower cut-off of structures included in the deterministic modelling of deformation zones. In order to take account of variability in data resolution, deterministic models for rock domains and deformation zones are presented in both regional and local scale model volumes, while the geological DFN model is valid only within specific fracture domains inside the Laxemar local model volume. The geological and geophysical data that constitute the basis for the SDM-Site Laxemar modelling work comprise all data that have been acquired from Laxemar, i.e. all data that were available at the data freeze for SDM-Site Laxemar at August 31, 2007. Selected quality controlled data from the complementary cored borehole KLX27A have also been utilised in the modelling work. Data from the following investigations were acquired during the complete site investigation between the data freezes for Laxemar 1.2 and SDM-Site Laxemar as defined above: A revised bedrock geological map at the ground surface. Geological and geophysical data from 40 new cored boreholes and 14 percussion boreholes. Sampling and subsequent modal and geochemical analytical work of bedrock samples taken in connection with excavations in southern Laxemar. Detailed mapping of fractures and rock units along 10 trench excavations and 2 large surface exposures (drill sites for KLX09 and KLX11A/KLX20A). Special studies involving more detailed characterisation of deformation zones identified in the geological single-hole interpretation

  8. Confidence assessment. Site-descriptive modelling SDM-Site Laxemar

    Energy Technology Data Exchange (ETDEWEB)

    2008-12-15

    The objective of this report is to assess the confidence that can be placed in the Laxemar site descriptive model, based on the information available at the conclusion of the surface-based investigations (SDM-Site Laxemar). In this exploration, an overriding question is whether remaining uncertainties are significant for repository engineering design or long-term safety assessment and could successfully be further reduced by more surface-based investigations or more usefully by explorations underground made during construction of the repository. Procedures for this assessment have been progressively refined during the course of the site descriptive modelling, and applied to all previous versions of the Forsmark and Laxemar site descriptive models. They include assessment of whether all relevant data have been considered and understood, identification of the main uncertainties and their causes, possible alternative models and their handling, and consistency between disciplines. The assessment then forms the basis for an overall confidence statement. The confidence in the Laxemar site descriptive model, based on the data available at the conclusion of the surface based site investigations, has been assessed by exploring: - Confidence in the site characterization data base, - remaining issues and their handling, - handling of alternatives, - consistency between disciplines and - main reasons for confidence and lack of confidence in the model. Generally, the site investigation database is of high quality, as assured by the quality procedures applied. It is judged that the Laxemar site descriptive model has an overall high level of confidence. Because of the relatively robust geological model that describes the site, the overall confidence in the Laxemar Site Descriptive model is judged to be high, even though details of the spatial variability remain unknown. The overall reason for this confidence is the wide spatial distribution of the data and the consistency between

  9. Bedrock hydrogeochemistry Forsmark. Site descriptive modelling SDM-Site Forsmark

    International Nuclear Information System (INIS)

    Laaksoharju, Marcus; Smellie, John; Tullborg, Eva-Lena; Gimeno, Maria; Hallbeck, Lotta; Molinero, Jorge; Waber, Nick

    2008-12-01

    The overall objectives of the hydrogeochemical site description for Forsmark are to establish a detailed understanding of the hydrogeochemical conditions at the site, and to use this understanding to develop models that address the needs identified by the safety assessment groups during the site investigation phase. Issues of concern to safety assessment are radionuclide transport and technical barrier behaviour, both of which are dependent on the chemistry of groundwater and porewater and their evolution with time. The specific aims of the hydrogeochemical work were: To document the hydrogeochemistry at the Forsmark site with focus on the development of conceptual models to describe and visualise the site. To provide relevant parameter values to be used for safety assessment calculations. To provide the hydrogeochemical basis for the modelling work by other teams, in particular hydrogeology. To take account of the feedback from the SR-Can safety assessment work that bears relevance to the hydrogeochemical modelling work. The work has involved the development of descriptive and mathematical models for groundwaters in relation to rock domains, fracture domains and deformation zones. In this report, the groundwaters have been interpreted in relation to their origin, evolution and composition, which require close integration with geological, climatological and hydrogeological information. Past climate changes are one of the major driving forces for long-term hydrogeochemical changes (hundreds to thousands of years) and are, therefore, of fundamental importance for understanding the palaeohydrogeological, palaeohydrogeochemical and present evolution of groundwater in the Fennoscandian crystalline bedrock. In contrast, redox buffer capacity of the bedrock will minimise the effects on changes in alkalinity and redox at repository depths, therefore limiting the variations in pH and Eh significantly, regardless of major changes in groundwater composition. There is

  10. Bedrock hydrogeochemistry Forsmark. Site descriptive modelling SDM-Site Forsmark

    Energy Technology Data Exchange (ETDEWEB)

    Laaksoharju, Marcus (Geopoint AB, Sollentuna (Sweden)); Smellie, John (Conterra AB, Partille (Sweden)); Tullborg, Eva-Lena (Terralogica, Graabo (Sweden)); Gimeno, Maria (Univ. of Zaragoza, Zaragoza (Spain)); Hallbeck, Lotta (Microbial Analytics, Goeteborg (Sweden)); Molinero, Jorge (Amphos XXI Consulting S.L., Barcelona (Spain)); Waber, Nick (Univ. of Bern, Bern (Switzerland))

    2008-12-15

    The overall objectives of the hydrogeochemical site description for Forsmark are to establish a detailed understanding of the hydrogeochemical conditions at the site, and to use this understanding to develop models that address the needs identified by the safety assessment groups during the site investigation phase. Issues of concern to safety assessment are radionuclide transport and technical barrier behaviour, both of which are dependent on the chemistry of groundwater and porewater and their evolution with time. The specific aims of the hydrogeochemical work were: To document the hydrogeochemistry at the Forsmark site with focus on the development of conceptual models to describe and visualise the site. To provide relevant parameter values to be used for safety assessment calculations. To provide the hydrogeochemical basis for the modelling work by other teams, in particular hydrogeology. To take account of the feedback from the SR-Can safety assessment work that bears relevance to the hydrogeochemical modelling work. The work has involved the development of descriptive and mathematical models for groundwaters in relation to rock domains, fracture domains and deformation zones. In this report, the groundwaters have been interpreted in relation to their origin, evolution and composition, which require close integration with geological, climatological and hydrogeological information. Past climate changes are one of the major driving forces for long-term hydrogeochemical changes (hundreds to thousands of years) and are, therefore, of fundamental importance for understanding the palaeohydrogeological, palaeohydrogeochemical and present evolution of groundwater in the Fennoscandian crystalline bedrock. In contrast, redox buffer capacity of the bedrock will minimise the effects on changes in alkalinity and redox at repository depths, therefore limiting the variations in pH and Eh significantly, regardless of major changes in groundwater composition. There is

  11. Background complementary hydrogeochemical studies. SDM-Site Forsmark

    International Nuclear Information System (INIS)

    Kalinowski, Birgitta E.

    2008-08-01

    The overall objectives of the hydrogeochemical description for Forsmark are to establish a detailed understanding of the hydrogeochemical conditions at the site and to develop models that fulfil the needs identified by the safety assessment groups during the site investigation phase. Issues of concern to safety assessment are radionuclide transport and technical barrier behaviour, both of which are dependent on the chemistry of groundwater and pore water and their evolution with time. The work has involved the development of descriptive and mathematical models for groundwaters in relation to rock domains, fracture domains and deformation zones. Past climate changes are one of the major driving forces for hydrogeochemical changes and therefore of fundamental importance for understanding the palaeohydrogeological, palaeohydrogeochemical and present evolution of groundwater in the crystalline bedrock of the Fennoscandian Shield. Understanding current undisturbed hydrochemical conditions at the proposed repository site is important when predicting future changes in groundwater chemistry. The causes of copper corrosion and/or bentonite degradation are of particular interest as they may jeopardise the long-term integrity of the planned SKB repository system. Thus, the following variables are considered for the hydrogeochemical site descriptive modelling: pH, Eh, sulphur species, iron, manganese, uranium, carbonate, phosphate, nitrogen species, total dissolved solids (TDS), isotopes, colloids, fulvic and humic acids and microorganisms. In addition, dissolved gases (e.g. carbon dioxide, methane and hydrogen) are of interest because of their likely participation in microbial reactions. In this series of reports, the final hydrogeochemical evaluation work of the site investigation at the Forsmark site, is presented. The work was conducted by SKB's hydrogeochemical project group, ChemNet, which consists of independent consultants and university researchers with expertise in

  12. Background complementary hydrogeochemical studies. SDM-Site Forsmark

    Energy Technology Data Exchange (ETDEWEB)

    Kalinowski, Birgitta E. (ed.)

    2008-08-15

    The overall objectives of the hydrogeochemical description for Forsmark are to establish a detailed understanding of the hydrogeochemical conditions at the site and to develop models that fulfil the needs identified by the safety assessment groups during the site investigation phase. Issues of concern to safety assessment are radionuclide transport and technical barrier behaviour, both of which are dependent on the chemistry of groundwater and pore water and their evolution with time. The work has involved the development of descriptive and mathematical models for groundwaters in relation to rock domains, fracture domains and deformation zones. Past climate changes are one of the major driving forces for hydrogeochemical changes and therefore of fundamental importance for understanding the palaeohydrogeological, palaeohydrogeochemical and present evolution of groundwater in the crystalline bedrock of the Fennoscandian Shield. Understanding current undisturbed hydrochemical conditions at the proposed repository site is important when predicting future changes in groundwater chemistry. The causes of copper corrosion and/or bentonite degradation are of particular interest as they may jeopardise the long-term integrity of the planned SKB repository system. Thus, the following variables are considered for the hydrogeochemical site descriptive modelling: pH, Eh, sulphur species, iron, manganese, uranium, carbonate, phosphate, nitrogen species, total dissolved solids (TDS), isotopes, colloids, fulvic and humic acids and microorganisms. In addition, dissolved gases (e.g. carbon dioxide, methane and hydrogen) are of interest because of their likely participation in microbial reactions. In this series of reports, the final hydrogeochemical evaluation work of the site investigation at the Forsmark site, is presented. The work was conducted by SKB's hydrogeochemical project group, ChemNet, which consists of independent consultants and university researchers with expertise

  13. Discrete-Feature Model Implementation of SDM-Site Forsmark

    International Nuclear Information System (INIS)

    Geier, Joel

    2010-03-01

    A discrete-feature model (DFM) was implemented for the Forsmark repository site based on the final site descriptive model from surface based investigations. The discrete-feature conceptual model represents deformation zones, individual fractures, and other water-conducting features around a repository as discrete conductors surrounded by a rock matrix which, in the present study, is treated as impermeable. This approximation is reasonable for sites in crystalline rock which has very low permeability, apart from that which results from macroscopic fracturing. Models are constructed based on the geological and hydrogeological description of the sites and engineering designs. Hydraulic heads and flows through the network of water-conducting features are calculated by the finite-element method, and are used in turn to simulate migration of non-reacting solute by a particle-tracking method, in order to estimate the properties of pathways by which radionuclides could be released to the biosphere. Stochastic simulation is used to evaluate portions of the model that can only be characterized in statistical terms, since many water-conducting features within the model volume cannot be characterized deterministically. Chapter 2 describes the methodology by which discrete features are derived to represent water-conducting features around the hypothetical repository at Forsmark (including both natural features and features that result from the disturbance of excavation), and then assembled to produce a discrete-feature network model for numerical simulation of flow and transport. Chapter 3 describes how site-specific data and repository design are adapted to produce the discrete-feature model. Chapter 4 presents results of the calculations. These include utilization factors for deposition tunnels based on the emplacement criteria that have been set forth by the implementers, flow distributions to the deposition holes, and calculated properties of discharge paths as well as

  14. Surface system Forsmark. Site descriptive modelling SDM-Site Forsmark

    International Nuclear Information System (INIS)

    Lindborg, Tobias

    2008-12-01

    SKB has undertaken site characterization of two different areas, Forsmark and Laxemar-Simpevarp, in order to find a suitable location for a geological repository for spent nuclear fuel. This report focuses on the site descriptive modelling of the surface system at Forsmark. The characterization of the surface system at the site was primarily made by identifying and describing important properties in different parts of the surface system, properties concerning e.g. hydrology and climate, Quaternary deposits and soils, hydrochemistry, vegetation, ecosystem functions, but also current and historical land use. The report presents available input data, methodology for data evaluation and modelling, and resulting models for each of the different disciplines. Results from the modelling of the surface system are also integrated with results from modelling of the deep bedrock system. The Forsmark site is located within the municipality of Oesthammar, about 120 km north of Stockholm. The investigated area is located along the shoreline of Oeregrundsgrepen, a funnel-shaped bay of the Baltic Sea. The area is characterized by small-scale topographic variations and is almost entirely located at altitudes lower than 20 metres above sea level. The Quaternary deposits in the area are dominated by till, characterized by a rich content of calcite which was transported by the glacier ice to the area from the sedimentary bedrock of Gaevlebukten about 100 km north of Forsmark. As a result, the surface waters and shallow groundwater at Forsmark are characterized by high pH values and high concentrations of certain major constituents, especially calcium and bicarbonate. The annual precipitation and runoff are 560 and 150 mm, respectively. The lakes are small and shallow, with mean and maximum depths ranging from approximately 0.1 to 1 m and 0.4 to 2 m. Sea water flows into the most low-lying lakes during events giving rise to very high sea levels. Wetlands are frequent and cover 25 to 35

  15. Surface system Forsmark. Site descriptive modelling SDM-Site Forsmark

    Energy Technology Data Exchange (ETDEWEB)

    Lindborg, Tobias (ed.)

    2008-12-15

    SKB has undertaken site characterization of two different areas, Forsmark and Laxemar-Simpevarp, in order to find a suitable location for a geological repository for spent nuclear fuel. This report focuses on the site descriptive modelling of the surface system at Forsmark. The characterization of the surface system at the site was primarily made by identifying and describing important properties in different parts of the surface system, properties concerning e.g. hydrology and climate, Quaternary deposits and soils, hydrochemistry, vegetation, ecosystem functions, but also current and historical land use. The report presents available input data, methodology for data evaluation and modelling, and resulting models for each of the different disciplines. Results from the modelling of the surface system are also integrated with results from modelling of the deep bedrock system. The Forsmark site is located within the municipality of Oesthammar, about 120 km north of Stockholm. The investigated area is located along the shoreline of Oeregrundsgrepen, a funnel-shaped bay of the Baltic Sea. The area is characterized by small-scale topographic variations and is almost entirely located at altitudes lower than 20 metres above sea level. The Quaternary deposits in the area are dominated by till, characterized by a rich content of calcite which was transported by the glacier ice to the area from the sedimentary bedrock of Gaevlebukten about 100 km north of Forsmark. As a result, the surface waters and shallow groundwater at Forsmark are characterized by high pH values and high concentrations of certain major constituents, especially calcium and bicarbonate. The annual precipitation and runoff are 560 and 150 mm, respectively. The lakes are small and shallow, with mean and maximum depths ranging from approximately 0.1 to 1 m and 0.4 to 2 m. Sea water flows into the most low-lying lakes during events giving rise to very high sea levels. Wetlands are frequent and cover 25 to 35

  16. Water-rock interaction modelling and uncertainties of mixing modelling. SDM-Site Laxemar

    Energy Technology Data Exchange (ETDEWEB)

    Gimeno, Maria J.; Auque, Luis F.; Gomez, Javier B.; Acero, Patricia (Univ. of Zaragoza, Zaragoza (Spain))

    2009-01-15

    The overall objectives of hydrogeochemical description for Laxemar are to establish a detailed understanding of the hydrogeochemical conditions at the site and to develop models that fulfil the needs identified by the safety assessment groups during the site investigation phase. Issues of concern to safety assessment are radionuclide transport and technical barrier behaviour, both of which are dependent on the chemistry of groundwater and pore water and their evolution with time. The work has involved the development of descriptive and mathematical models for groundwaters in relation to rock domains, fracture domains and deformation zones. Past climate changes are the major driving force for hydrogeochemical changes and therefore of fundamental importance for understanding the palaeohydrogeological, palaeohydrogeochemical and present evolution of groundwater in the crystalline bedrock of the Fennoscandian Shield. Understanding current undisturbed hydrochemical conditions at the proposed repository site is important when predicting future changes in groundwater chemistry. The causes of copper corrosion and/or bentonite degradation are of particular interest as they may jeopardise the long-term integrity of the planned SKB repository system. Thus, the following variables are considered for the hydrogeochemical site descriptive modelling: pH, Eh, sulphur species, iron, manganese, carbonate, phosphate, nitrogen species, total dissolved solids (TDS), isotopes, colloids, fulvic and humic acids and microorganisms. In addition, dissolved gases (e.g. carbon dioxide, methane and hydrogen) are of interest because of their likely participation in microbial reactions. In this series of reports, the final hydrogeochemical evaluation work of the site investigation at the Laxemar site, is presented. The work was conducted by SKB's hydrogeochemical project group, ChemNet, which consists of independent consultants and Univ. researchers with expertise in geochemistry

  17. Water-rock interaction modelling and uncertainties of mixing modelling. SDM-Site Laxemar

    International Nuclear Information System (INIS)

    Gimeno, Maria J.; Auque, Luis F.; Gomez, Javier B.; Acero, Patricia

    2009-01-01

    The overall objectives of hydrogeochemical description for Laxemar are to establish a detailed understanding of the hydrogeochemical conditions at the site and to develop models that fulfil the needs identified by the safety assessment groups during the site investigation phase. Issues of concern to safety assessment are radionuclide transport and technical barrier behaviour, both of which are dependent on the chemistry of groundwater and pore water and their evolution with time. The work has involved the development of descriptive and mathematical models for groundwaters in relation to rock domains, fracture domains and deformation zones. Past climate changes are the major driving force for hydrogeochemical changes and therefore of fundamental importance for understanding the palaeohydrogeological, palaeohydrogeochemical and present evolution of groundwater in the crystalline bedrock of the Fennoscandian Shield. Understanding current undisturbed hydrochemical conditions at the proposed repository site is important when predicting future changes in groundwater chemistry. The causes of copper corrosion and/or bentonite degradation are of particular interest as they may jeopardise the long-term integrity of the planned SKB repository system. Thus, the following variables are considered for the hydrogeochemical site descriptive modelling: pH, Eh, sulphur species, iron, manganese, carbonate, phosphate, nitrogen species, total dissolved solids (TDS), isotopes, colloids, fulvic and humic acids and microorganisms. In addition, dissolved gases (e.g. carbon dioxide, methane and hydrogen) are of interest because of their likely participation in microbial reactions. In this series of reports, the final hydrogeochemical evaluation work of the site investigation at the Laxemar site, is presented. The work was conducted by SKB's hydrogeochemical project group, ChemNet, which consists of independent consultants and Univ. researchers with expertise in geochemistry, hydrochemistry

  18. Geological evolution, palaeoclimate and historical development of the Forsmark and Laxemar-Simpevarp areas. Site descriptive modelling SDM-Site

    International Nuclear Information System (INIS)

    Soederbaeck, Bjoern

    2008-06-01

    The Swedish Nuclear Fuel and Waste Management Company (SKB) is undertaking site characterization at two different locations, the Forsmark and Laxemar-Simpevarp areas, with the objective of siting a geological repository for spent nuclear fuel. The site investigations started in 2002 and were completed in 2007. The analysis and modelling of data from the site investigations, which have taken place during and after these investigations, provide a foundation for the development of an integrated, multidisciplinary site descriptive model (SDM) for each of the two sites. A site descriptive model constitutes a description of the site and its regional setting, covering the current state of the geosphere and the biosphere, as well as those natural processes that affect or have affected their long-term development. Hitherto, a number of reports presenting preliminary site descriptive models for Forsmark and Laxemar-Simpevarp have been published. In these reports, the evolutionary and historical aspects of the site were included in a separate chapter. The present report comprises a further elaboration of the evolutionary and historical information included in the preliminary SDM reports, but presented here in a separate, supplementary report to the final site description, SDM-Site. The report is common to the two investigated areas, and the overall objective is to describe the long-term geological evolution, the palaeoclimate, and the post-glacial development of ecosystems and of the human population at the two sites. The report largely consists of a synthesis of information derived from the scientific literature and other sources not related to the site investigations. However, considerable information from the site investigations that has contributed to our understanding of the past development at each site is also included. This unique synthesis of both published information in a regional perspective and new site-specific information breaks new ground in our understanding

  19. Geological evolution, palaeoclimate and historical development of the Forsmark and Laxemar-Simpevarp areas. Site descriptive modelling SDM-Site

    Energy Technology Data Exchange (ETDEWEB)

    Soederbaeck, Bjoern (ed.)

    2008-06-15

    The Swedish Nuclear Fuel and Waste Management Company (SKB) is undertaking site characterization at two different locations, the Forsmark and Laxemar-Simpevarp areas, with the objective of siting a geological repository for spent nuclear fuel. The site investigations started in 2002 and were completed in 2007. The analysis and modelling of data from the site investigations, which have taken place during and after these investigations, provide a foundation for the development of an integrated, multidisciplinary site descriptive model (SDM) for each of the two sites. A site descriptive model constitutes a description of the site and its regional setting, covering the current state of the geosphere and the biosphere, as well as those natural processes that affect or have affected their long-term development. Hitherto, a number of reports presenting preliminary site descriptive models for Forsmark and Laxemar-Simpevarp have been published. In these reports, the evolutionary and historical aspects of the site were included in a separate chapter. The present report comprises a further elaboration of the evolutionary and historical information included in the preliminary SDM reports, but presented here in a separate, supplementary report to the final site description, SDM-Site. The report is common to the two investigated areas, and the overall objective is to describe the long-term geological evolution, the palaeoclimate, and the post-glacial development of ecosystems and of the human population at the two sites. The report largely consists of a synthesis of information derived from the scientific literature and other sources not related to the site investigations. However, considerable information from the site investigations that has contributed to our understanding of the past development at each site is also included. This unique synthesis of both published information in a regional perspective and new site-specific information breaks new ground in our understanding

  20. Geological discrete fracture network model for the Laxemar site. Site Descriptive Modelling. SDM-Site Laxemar

    Energy Technology Data Exchange (ETDEWEB)

    La Pointe, Paul; Fox, Aaron (Golder Associates Inc (United States)); Hermanson, Jan; Oehman, Johan (Golder Associates AB, Stockholm (Sweden))

    2008-12-15

    The Swedish Nuclear Fuel and Waste Management Company (SKB) is performing site characterization at two different locations, Forsmark and Laxemar, in order to locate a site for a final geologic repository for spent nuclear fuel. The program is built upon the development of Site Descriptive Models (SDMs) at specific timed data freezes. Each SDM is formed from discipline-specific reports from across the scientific spectrum. This report describes the methods, analyses, and conclusions of the modelling team in the production of the SDM-Site Laxemar geological discrete-fracture network (DFN) model. The DFN builds upon the work of other geological models, including the deformation zone and rock domain models. The geological DFN is a statistical model for stochastically simulating rock fractures and minor deformation zones at a scale of less than 1,000 m (the lower cut-off of the DZ models). The geological DFN is valid within six distinct fracture domains inside the Laxemar local model subarea: FSM{sub C}, FSM{sub E}W007, FSM{sub N}, FSM{sub N}E005, FSM{sub S}, and FSM{sub W}. The models are built using data from detailed surface outcrop maps, geophysical lineament maps, and the cored borehole record at Laxemar. The conceptual model for the SDM-Site Laxemar geological DFN model revolves around the identification of fracture domains based on relative fracture set intensities, orientation clustering, and the regional tectonic framework (including deformation zones). A single coupled fracture size/fracture intensity concept (the Base Model) based on a Pareto (power-law) distribution for fracture sizes was chosen as the recommended parameterisation. A slew of alternative size-intensity models were also carried through the fracture analyses and into the uncertainty and model verification analyses. Uncertainty is modelled by analysing the effects on fracture intensity (P32) that alternative model cases can have. Uncertainty is parameterised as a ratio between the P32 of the

  1. Geological discrete fracture network model for the Laxemar site. Site Descriptive Modelling. SDM-Site Laxemar

    International Nuclear Information System (INIS)

    La Pointe, Paul; Fox, Aaron; Hermanson, Jan; Oehman, Johan

    2008-10-01

    The Swedish Nuclear Fuel and Waste Management Company (SKB) is performing site characterization at two different locations, Forsmark and Laxemar, in order to locate a site for a final geologic repository for spent nuclear fuel. The program is built upon the development of Site Descriptive Models (SDMs) at specific timed data freezes. Each SDM is formed from discipline-specific reports from across the scientific spectrum. This report describes the methods, analyses, and conclusions of the modelling team in the production of the SDM-Site Laxemar geological discrete-fracture network (DFN) model. The DFN builds upon the work of other geological models, including the deformation zone and rock domain models. The geological DFN is a statistical model for stochastically simulating rock fractures and minor deformation zones at a scale of less than 1,000 m (the lower cut-off of the DZ models). The geological DFN is valid within six distinct fracture domains inside the Laxemar local model subarea: FSM C , FSM E W007, FSM N , FSM N E005, FSM S , and FSM W . The models are built using data from detailed surface outcrop maps, geophysical lineament maps, and the cored borehole record at Laxemar. The conceptual model for the SDM-Site Laxemar geological DFN model revolves around the identification of fracture domains based on relative fracture set intensities, orientation clustering, and the regional tectonic framework (including deformation zones). A single coupled fracture size/fracture intensity concept (the Base Model) based on a Pareto (power-law) distribution for fracture sizes was chosen as the recommended parameterisation. A slew of alternative size-intensity models were also carried through the fracture analyses and into the uncertainty and model verification analyses. Uncertainty is modelled by analysing the effects on fracture intensity (P32) that alternative model cases can have. Uncertainty is parameterised as a ratio between the P32 of the alternative model and the P

  2. Description of surface hydrology and near-surface hydrogeology at Forsmark. Site descriptive modelling SDM. Site Forsmark

    International Nuclear Information System (INIS)

    Johansson, Per-Olof

    2008-12-01

    This report describes the modelling of the surface hydrology and near-surface hydrogeology that was performed for the final site descriptive model of Forsmark produced in the site investigation stage, SDM-Site Forsmark. The comprehensive investigation and monitoring programme forms a strong basis for the developed conceptual and descriptive model of the hydrological and near-surface hydrological system of the site investigation area. However, there are some remaining uncertainties regarding the interaction of deep and near-surface groundwater and surface water of importance for the understanding of the system: The groundwaters in till below Lake Eckarfjaerden, Lake Gaellbotraesket, Lake Fiskarfjaerden and Lake Bolundsfjaerden have high salinities. The hydrological and hydrochemical interpretations indicate that these waters are relict waters of mainly marine origin. From the perspective of the overall water balance, the water below the central parts of the lakes can be considered as stagnant. However, according to the hydrochemical interpretation, these waters also contain weak signatures of deep saline water. Rough chloride budget calculations for the Gaellbotraesket depression also raise the question of a possible upward flow of deep groundwater. No absolute conclusion can be drawn from the existing data analyses regarding the key question of whether there is a small ongoing upward flow of deep saline water. However, Lake Bolundsfjaerden is an exception where the clear downward flow gradient from the till to the bedrock excludes the possibility of an active deep saline source. The available data indicate that there are no discharge areas for flow systems involving deep bedrock groundwater in the northern part of the tectonic lens, where the repository is planned to be located (the so-called 'target area'). However, it can not be excluded that such discharge areas exist. Data indicate that the prevailing downward vertical flow gradients from the QD to the bedrock

  3. Description of surface hydrology and near-surface hydrogeology at Forsmark. Site descriptive modelling SDM. Site Forsmark

    Energy Technology Data Exchange (ETDEWEB)

    Johansson, Per-Olof (Artesia Grundvattenkonsult AB, Taeby (Sweden))

    2008-12-15

    This report describes the modelling of the surface hydrology and near-surface hydrogeology that was performed for the final site descriptive model of Forsmark produced in the site investigation stage, SDM-Site Forsmark. The comprehensive investigation and monitoring programme forms a strong basis for the developed conceptual and descriptive model of the hydrological and near-surface hydrological system of the site investigation area. However, there are some remaining uncertainties regarding the interaction of deep and near-surface groundwater and surface water of importance for the understanding of the system: The groundwaters in till below Lake Eckarfjaerden, Lake Gaellbotraesket, Lake Fiskarfjaerden and Lake Bolundsfjaerden have high salinities. The hydrological and hydrochemical interpretations indicate that these waters are relict waters of mainly marine origin. From the perspective of the overall water balance, the water below the central parts of the lakes can be considered as stagnant. However, according to the hydrochemical interpretation, these waters also contain weak signatures of deep saline water. Rough chloride budget calculations for the Gaellbotraesket depression also raise the question of a possible upward flow of deep groundwater. No absolute conclusion can be drawn from the existing data analyses regarding the key question of whether there is a small ongoing upward flow of deep saline water. However, Lake Bolundsfjaerden is an exception where the clear downward flow gradient from the till to the bedrock excludes the possibility of an active deep saline source. The available data indicate that there are no discharge areas for flow systems involving deep bedrock groundwater in the northern part of the tectonic lens, where the repository is planned to be located (the so-called 'target area'). However, it can not be excluded that such discharge areas exist. Data indicate that the prevailing downward vertical flow gradients from the QD to

  4. Validation of coastal oceanographic models at Forsmark. Site descriptive modelling SDM-Site Forsmark

    Energy Technology Data Exchange (ETDEWEB)

    Engqvist, Anders (A och I Engqvist Konsult HB, Vaxholm (SE)); Andrejev, Oleg (Finnish Inst. of Marine Research, Helsinki (FI))

    2008-01-15

    The Swedish Nuclear Fuel and Waste Management Company (SKB) is undertaking site characterisation at two different locations, the Forsmark and the Simpevarp areas, with the objective of siting a geological repository for spent nuclear fuel. The characterisation work is divided into an initial site investigation phase and a complete site investigation phase. In this context, the water exchange of the coastal zone is one link of the chain of possible nuclide transport mechanisms that must be assessed in the site description of potential repository areas. For the purpose of validating the pair of nested 3D-models employed to simulate the water exchange in the near-shore coastal zone in the Forsmark area, an encompassing measurement program entailing six stations has been performed. The design of this program was to first assess to what degree the forcing of the fine resolution (FR) model of the Forsmark study area at its interfacial boundary to the coarse resolution (CR) model of the entire Baltic was reproduced. In addition to this scrutiny it is of particular interest how the time-varying density-determining properties, salinity and temperature, at the borders are propagated into the FR-domain, since this corresponds to the most efficient mode of water exchange. An important part of the validation process has been to carefully evaluate which measurement data that can be considered reliable. The result was that several periods of foremost near-surface salinity data had to be discarded due to growth of algae on the conductivity sensors. Lack of thorough absolute calibration of the salinity meters also necessitates dismissal of measurement data. Relative the assessed data that can be accepted as adequate, the outcome of the validation can be summarized in five points: (i) The surface-most salinity of the CR-model drifts downward a little less than one practical salinity unit (psu) per year, requiring that the ensuing correlation analysis be subdivided into periods of a

  5. Validation of coastal oceanographic models at Forsmark. Site descriptive modelling SDM-Site Forsmark

    International Nuclear Information System (INIS)

    Engqvist, Anders; Andrejev, Oleg

    2008-01-01

    The Swedish Nuclear Fuel and Waste Management Company (SKB) is undertaking site characterisation at two different locations, the Forsmark and the Simpevarp areas, with the objective of siting a geological repository for spent nuclear fuel. The characterisation work is divided into an initial site investigation phase and a complete site investigation phase. In this context, the water exchange of the coastal zone is one link of the chain of possible nuclide transport mechanisms that must be assessed in the site description of potential repository areas. For the purpose of validating the pair of nested 3D-models employed to simulate the water exchange in the near-shore coastal zone in the Forsmark area, an encompassing measurement program entailing six stations has been performed. The design of this program was to first assess to what degree the forcing of the fine resolution (FR) model of the Forsmark study area at its interfacial boundary to the coarse resolution (CR) model of the entire Baltic was reproduced. In addition to this scrutiny it is of particular interest how the time-varying density-determining properties, salinity and temperature, at the borders are propagated into the FR-domain, since this corresponds to the most efficient mode of water exchange. An important part of the validation process has been to carefully evaluate which measurement data that can be considered reliable. The result was that several periods of foremost near-surface salinity data had to be discarded due to growth of algae on the conductivity sensors. Lack of thorough absolute calibration of the salinity meters also necessitates dismissal of measurement data. Relative the assessed data that can be accepted as adequate, the outcome of the validation can be summarized in five points: (i) The surface-most salinity of the CR-model drifts downward a little less than one practical salinity unit (psu) per year, requiring that the ensuing correlation analysis be subdivided into periods of a

  6. Explorative analysis of major components and isotopes. SDM-Site Forsmark

    International Nuclear Information System (INIS)

    Smellie, John; Tullborg, Eva-Lena; Nilsson, Ann-Chatrin; Sandstroem, Bjoern; Waber, Niklaus; Gimeno, Maria; Gascoyne, Mel

    2008-09-01

    The overall objectives of the hydrogeochemical description for Forsmark are to establish a detailed understanding of the hydrogeochemical conditions at the site and to develop models that fulfil the needs identified by the safety assessment groups during the site investigation phase. Issues of concern to safety assessment are radionuclide transport and technical barrier behaviour, both of which are dependent on the chemistry of groundwater and pore water and their evolution with time. The work has involved the development of descriptive and mathematical models for groundwaters in relation to rock domains, fracture domains and deformation zones. Past climate events are the major driving force for hydrogeochemical changes and therefore are of fundamental importance for understanding the palaeohydrogeological, palaeohydrogeochemical and present evolution of groundwater in the crystalline bedrock of the Fennoscandian Shield. Understanding current undisturbed hydrochemical conditions at the proposed repository site is important when predicting future changes in groundwater chemistry. The causes behind copper corrosion and/or bentonite degradation are of particular interest as they may jeopardise the long-term integrity of the planned SKB repository system. Thus, the following variables are considered for the hydrogeochemical site descriptive modelling: pH, Eh, sulphur species, iron, manganese, carbonate, phosphate, nitrogen species, total dissolved solids (TDS), isotopes, colloids, fulvic and humic acids and microorganisms. In addition, dissolved gases (e.g. carbon dioxide, methane and hydrogen) are of interest because of their likely participation in microbial reactions. In this series of reports, the final hydrogeochemical evaluation work of the site investigation at the Forsmark site, is presented. The work was conducted by SKB's hydrogeochemical project group, ChemNet, which consists of independent consultants and university researchers with expertise in

  7. Explorative analysis of major components and isotopes. SDM-Site Forsmark

    Energy Technology Data Exchange (ETDEWEB)

    Smellie, John (Conterra AB (Sweden)); Tullborg, Eva-Lena (Terralogica AB (Sweden)); Nilsson, Ann-Chatrin (Geosigma AB (Sweden)); Sandstroem, Bjoern (Goeteborg Univ. (Sweden)); Waber, Niklaus (Univ. of Bern (Switzerland)); Gimeno, Maria (Univ. of Zaragoza (Spain)); Gascoyne, Mel (GGP Inc. (United Kingdom))

    2008-09-15

    The overall objectives of the hydrogeochemical description for Forsmark are to establish a detailed understanding of the hydrogeochemical conditions at the site and to develop models that fulfil the needs identified by the safety assessment groups during the site investigation phase. Issues of concern to safety assessment are radionuclide transport and technical barrier behaviour, both of which are dependent on the chemistry of groundwater and pore water and their evolution with time. The work has involved the development of descriptive and mathematical models for groundwaters in relation to rock domains, fracture domains and deformation zones. Past climate events are the major driving force for hydrogeochemical changes and therefore are of fundamental importance for understanding the palaeohydrogeological, palaeohydrogeochemical and present evolution of groundwater in the crystalline bedrock of the Fennoscandian Shield. Understanding current undisturbed hydrochemical conditions at the proposed repository site is important when predicting future changes in groundwater chemistry. The causes behind copper corrosion and/or bentonite degradation are of particular interest as they may jeopardise the long-term integrity of the planned SKB repository system. Thus, the following variables are considered for the hydrogeochemical site descriptive modelling: pH, Eh, sulphur species, iron, manganese, carbonate, phosphate, nitrogen species, total dissolved solids (TDS), isotopes, colloids, fulvic and humic acids and microorganisms. In addition, dissolved gases (e.g. carbon dioxide, methane and hydrogen) are of interest because of their likely participation in microbial reactions. In this series of reports, the final hydrogeochemical evaluation work of the site investigation at the Forsmark site, is presented. The work was conducted by SKB's hydrogeochemical project group, ChemNet, which consists of independent consultants and university researchers with expertise in

  8. Validation of coastal oceanographic models at Laxemar-Simpevarp. Site descriptive modelling SDM-Site Laxemar

    Energy Technology Data Exchange (ETDEWEB)

    Engqvist, Anders (A och I Engqvist Konsult HB, Vaxholm (SE)); Andrejev, Oleg (Finnish Inst. of Marine Research, Helsinki (FI))

    2008-12-15

    The Swedish Nuclear Fuel and Waste Management Company (SKB) is undertaking site characterization at two different locations, the Forsmark and the Laxemar-Simpevarp areas, with the objective of siting a geological repository for spent nuclear fuel. The characterization work is divided into an initial site investigation phase and a complete site investigation phase. In this context, the water exchange of the coastal zone is one link of the chain of possible nuclide transport mechanisms that must be assessed in the site description of potential repository areas. For the purpose of validating the pair of nested 3D-models and the coupled discrete basin (CDB-) model employed to simulate the water exchange in the near-shore coastal zone in the Laxemar-Simpevarp area, an encompassing measurement program entailing data from six stations (of which two are close) has been performed. The design of this program was to first assess to what degree the forcing of the fine resolution (FR-) model of the Laxemar- Simpevarp study area at its interfacial boundary to the coarse resolution (CR-) model of the entire Baltic was reproduced. In addition to this, it is of particular interest how the time-varying density-determining properties, salinity and temperature, at the borders are propagated into the FR-domain and further influence the water exchange with the interior, more secluded, basins. An important part of the validation process has been to carefully evaluate which measurement data that can be considered reliable. The result was that some periods of foremost near-surface salinity data had to be discarded due to growth of algae on the conductivity sensors. Interference with ship traffic and lack of absolute calibration of the salinity meters necessitated dismissal of measurement data too. In this study so-called Mesan data have been consistently used for the meteorological forcing of the 3D-models. Relative the assessed data that can be accepted as adequate, the outcome of the

  9. Validation of coastal oceanographic models at Laxemar-Simpevarp. Site descriptive modelling SDM-Site Laxemar

    International Nuclear Information System (INIS)

    Engqvist, Anders; Andrejev, Oleg

    2008-12-01

    The Swedish Nuclear Fuel and Waste Management Company (SKB) is undertaking site characterization at two different locations, the Forsmark and the Laxemar-Simpevarp areas, with the objective of siting a geological repository for spent nuclear fuel. The characterization work is divided into an initial site investigation phase and a complete site investigation phase. In this context, the water exchange of the coastal zone is one link of the chain of possible nuclide transport mechanisms that must be assessed in the site description of potential repository areas. For the purpose of validating the pair of nested 3D-models and the coupled discrete basin (CDB-) model employed to simulate the water exchange in the near-shore coastal zone in the Laxemar-Simpevarp area, an encompassing measurement program entailing data from six stations (of which two are close) has been performed. The design of this program was to first assess to what degree the forcing of the fine resolution (FR-) model of the Laxemar- Simpevarp study area at its interfacial boundary to the coarse resolution (CR-) model of the entire Baltic was reproduced. In addition to this, it is of particular interest how the time-varying density-determining properties, salinity and temperature, at the borders are propagated into the FR-domain and further influence the water exchange with the interior, more secluded, basins. An important part of the validation process has been to carefully evaluate which measurement data that can be considered reliable. The result was that some periods of foremost near-surface salinity data had to be discarded due to growth of algae on the conductivity sensors. Interference with ship traffic and lack of absolute calibration of the salinity meters necessitated dismissal of measurement data too. In this study so-called Mesan data have been consistently used for the meteorological forcing of the 3D-models. Relative the assessed data that can be accepted as adequate, the outcome of the

  10. Water-rock interaction modelling and uncertainties of mixing modelling. SDM-Site Forsmark

    Energy Technology Data Exchange (ETDEWEB)

    Gimeno, Maria J.; Auque, Luis F.; Gomez, Javier B.; Acero, Patricia (Univ. of Zaragoza, Zaragoza (Spain))

    2008-08-15

    The overall objectives of the hydrogeochemical description for Forsmark are to establish a detailed understanding of the hydrogeochemical conditions at the site and to develop models that fulfil the needs identified by the safety assessment groups during the site investigation phase. Issues of concern to safety assessment are radionuclide transport and technical barrier behaviour, both of which are dependent on the chemistry of groundwater and pore water and their evolution with time. The work has involved the development of descriptive and mathematical models for groundwaters in relation to rock domains, fracture domains and deformation zones. Past climate changes are one of the major driving forces for hydrogeochemical changes and therefore of fundamental importance for understanding the palaeohydrogeological, palaeohydrogeochemical and present evolution of groundwater in the crystalline bedrock of the Fennoscandian Shield. Understanding current undisturbed hydrochemical conditions at the proposed repository site is important when predicting future changes in groundwater chemistry. The causes behind of copper corrosion and/or bentonite degradation are of particular interest as they may jeopardise the long-term integrity of the planned SKB repository system. Thus, the following variables are considered for the hydrogeochemical site descriptive modelling: pH, Eh, sulphur species, iron, manganese, carbonate, phosphate, nitrogen species, total dissolved solids (TDS), isotopes, colloids, fulvic and humic acids and microorganisms. In addition, dissolved gases (e.g. carbon dioxide, methane and hydrogen) are of interest because of their likely participation in microbial reactions. In this series of reports, the final hydrogeochemical evaluation work of the site investigation at the Forsmark site, is presented. The work was conducted by SKB's hydrogeochemical project group, ChemNet, which consists of independent consultants and university researchers with expertise

  11. Water-rock interaction modelling and uncertainties of mixing modelling. SDM-Site Forsmark

    International Nuclear Information System (INIS)

    Gimeno, Maria J.; Auque, Luis F.; Gomez, Javier B.; Acero, Patricia

    2008-08-01

    The overall objectives of the hydrogeochemical description for Forsmark are to establish a detailed understanding of the hydrogeochemical conditions at the site and to develop models that fulfil the needs identified by the safety assessment groups during the site investigation phase. Issues of concern to safety assessment are radionuclide transport and technical barrier behaviour, both of which are dependent on the chemistry of groundwater and pore water and their evolution with time. The work has involved the development of descriptive and mathematical models for groundwaters in relation to rock domains, fracture domains and deformation zones. Past climate changes are one of the major driving forces for hydrogeochemical changes and therefore of fundamental importance for understanding the palaeohydrogeological, palaeohydrogeochemical and present evolution of groundwater in the crystalline bedrock of the Fennoscandian Shield. Understanding current undisturbed hydrochemical conditions at the proposed repository site is important when predicting future changes in groundwater chemistry. The causes behind of copper corrosion and/or bentonite degradation are of particular interest as they may jeopardise the long-term integrity of the planned SKB repository system. Thus, the following variables are considered for the hydrogeochemical site descriptive modelling: pH, Eh, sulphur species, iron, manganese, carbonate, phosphate, nitrogen species, total dissolved solids (TDS), isotopes, colloids, fulvic and humic acids and microorganisms. In addition, dissolved gases (e.g. carbon dioxide, methane and hydrogen) are of interest because of their likely participation in microbial reactions. In this series of reports, the final hydrogeochemical evaluation work of the site investigation at the Forsmark site, is presented. The work was conducted by SKB's hydrogeochemical project group, ChemNet, which consists of independent consultants and university researchers with expertise in

  12. Description of regolith at Laxemar-Simpevarp. Site descriptive modelling SDM-Site Laxemar

    International Nuclear Information System (INIS)

    Sohlenius, Gustav; Hedenstroem, Anna

    2008-11-01

    This report compiles all known available information regarding the regolith in the Laxemar-Simpevarp regional model area. Regolith refers to the loose deposits overlying the bedrock. In the Laxemar-Simpevarp area, all known regolith was deposited during the Quaternary period and is consequently often referred to as Quaternary deposits (QD). In the terrestrial areas the uppermost part of the regolith, which has been affected by climate and vegetation, is referred to as soil. The geographical and stratigraphical distributions of the regolith have been used to construct a model showing the distribution of regolith depths in the whole model area. The stratigraphical units shown in the regolith depth and stratigraphy model have been characterised with respect to physical and chemical properties. Most of the data used for that characterisation have been obtained from the site investigation but some data were taken from the literature. All QD in the Laxemar area have most probably been deposited during or after the latest deglaciation. The ice sheet in the area moved from the north-west during the latest ice age. The Baltic Sea completely covered the investigated area after the latest deglaciation c 12,000 BC. Land uplift was fastest during the first few thousand years following the deglaciation and has subsequently decreased to the present value of 1 mm/year. Older QD have been eroded in areas exposed to waves and currents and the material has later been redeposited. Fine-grained sediments have been deposited on the floor of bays and in other sheltered positions. Peat has accumulated in many of the wetlands situated in topographically low positions. The groundwater table in many of the former wetlands has been artificially lowered to obtain land for forestry and agriculture, which has caused the peat to partly or completely oxidise. As land uplift proceeds, some new areas are being subjected to erosion at the same time as other new areas are becoming lakes and sheltered

  13. Description of regolith at Laxemar-Simpevarp. Site descriptive modelling SDM-Site Laxemar

    Energy Technology Data Exchange (ETDEWEB)

    Sohlenius, Gustav; Hedenstroem, Anna (Geological Survey of Sweden (SGU), Uppsala (Sweden))

    2008-11-15

    This report compiles all known available information regarding the regolith in the Laxemar-Simpevarp regional model area. Regolith refers to the loose deposits overlying the bedrock. In the Laxemar-Simpevarp area, all known regolith was deposited during the Quaternary period and is consequently often referred to as Quaternary deposits (QD). In the terrestrial areas the uppermost part of the regolith, which has been affected by climate and vegetation, is referred to as soil. The geographical and stratigraphical distributions of the regolith have been used to construct a model showing the distribution of regolith depths in the whole model area. The stratigraphical units shown in the regolith depth and stratigraphy model have been characterised with respect to physical and chemical properties. Most of the data used for that characterisation have been obtained from the site investigation but some data were taken from the literature. All QD in the Laxemar area have most probably been deposited during or after the latest deglaciation. The ice sheet in the area moved from the north-west during the latest ice age. The Baltic Sea completely covered the investigated area after the latest deglaciation c 12,000 BC. Land uplift was fastest during the first few thousand years following the deglaciation and has subsequently decreased to the present value of 1 mm/year. Older QD have been eroded in areas exposed to waves and currents and the material has later been redeposited. Fine-grained sediments have been deposited on the floor of bays and in other sheltered positions. Peat has accumulated in many of the wetlands situated in topographically low positions. The groundwater table in many of the former wetlands has been artificially lowered to obtain land for forestry and agriculture, which has caused the peat to partly or completely oxidise. As land uplift proceeds, some new areas are being subjected to erosion at the same time as other new areas are becoming lakes and sheltered

  14. Explorative analysis of microbes, colloids and gases together with microbial modelling. Site description model SDM-Site Laxemar

    International Nuclear Information System (INIS)

    Hallbeck, Lotta; Pedersen, Karsten

    2008-08-01

    microorganisms. Different microbial groups influence the environment in different ways, depending on what metabolic group is dominant. Typically, the following redox couples are utilized by bacteria in granitic groundwater: H 2 O/O 2 , NO 3 - /N 2 , Mn 2+ /Mn(IV), Fe 2+ /Fe(III), S 2- /SO 4 2- , CH 4 /CO 2 , CH 3 COOH/CO 2 , and H 2 /H + . The data will indicate the activity of specific microbial populations at particular sites and how they may affect the geochemistry. Particles in the size range from 1 to 1 x 10 -3 μm are regarded as colloids. Their small size prohibits them from settling, which gives them the potential to transport radionuclides in groundwater. The aim of the study of colloids in the Laxemar 2.3 site investigation was to quantify and determine the composition of colloids in groundwater samples from the boreholes. There are both inorganic and organic colloids, and the site investigation measured both types. Dissolved gases in groundwater contribute to the mass of dissolved species. The distribution and composition of dissolved gases in deep groundwater are important to understand in the safety assessment of a deep geological nuclear waste repository: Micro bubbles of gas may potentially transport radionuclides from the repository to the surface. Oxygen, hydrogen sulphide and carbon dioxide are parts of fundamental redox couples that participate in several solid-aqueous phase transformations such as the precipitation of ferric iron oxides, iron sulphide and calcite. Methane and hydrogen, may serve as sources of energy to various microbiological processes

  15. Explorative analysis of microbes, colloids and gases together with microbial modelling. Site description model SDM-Site Laxemar

    Energy Technology Data Exchange (ETDEWEB)

    Hallbeck, Lotta; Pedersen, Karsten (Microbial Analytics Sweden AB, Goeteborg (Sweden))

    2008-08-15

    microorganisms. Different microbial groups influence the environment in different ways, depending on what metabolic group is dominant. Typically, the following redox couples are utilized by bacteria in granitic groundwater: H{sub 2}O/O{sub 2}, NO{sub 3}-/N{sub 2}, Mn2+/Mn(IV), Fe2+/Fe(III), S2-/SO{sub 4}2-, CH{sub 4}/CO{sub 2}, CH{sub 3}COOH/CO{sub 2}, and H{sub 2}/H+. The data will indicate the activity of specific microbial populations at particular sites and how they may affect the geochemistry. Particles in the size range from 1 to 1 x 10-3 mum are regarded as colloids. Their small size prohibits them from settling, which gives them the potential to transport radionuclides in groundwater. The aim of the study of colloids in the Laxemar 2.3 site investigation was to quantify and determine the composition of colloids in groundwater samples from the boreholes. There are both inorganic and organic colloids, and the site investigation measured both types. Dissolved gases in groundwater contribute to the mass of dissolved species. The distribution and composition of dissolved gases in deep groundwater are important to understand in the safety assessment of a deep geological nuclear waste repository: Micro bubbles of gas may potentially transport radionuclides from the repository to the surface. Oxygen, hydrogen sulphide and carbon dioxide are parts of fundamental redox couples that participate in several solid-aqueous phase transformations such as the precipitation of ferric iron oxides, iron sulphide and calcite. Methane and hydrogen, may serve as sources of energy to various microbiological processes

  16. Numerical modelling of surface hydrology and near-surface hydrogeology at Forsmark. Site descriptive modelling SDM. Site Forsmark

    International Nuclear Information System (INIS)

    Bosson, Emma; Gustafsson, Lars-Goeran; Sassner, Mona

    2008-09-01

    SKB is currently performing site investigations at two potential sites for a final repository for spent nuclear fuel. This report presents results of water flow and solute transport modelling of the Forsmark site. The modelling reported in this document focused on the near-surface groundwater, i.e. groundwater in Quaternary deposits and shallow rock, and surface water systems, and was performed using the MIKE SHE tool. The most recent site data used in the modelling were delivered in the Forsmark 2.3 dataset, which had its 'data freeze' on March 31, 2007. The present modelling is performed in support of the final version of the Forsmark site description that is produced during the site investigation phase. In this work, the hydrological modelling system MIKE SHE has been used to describe near-surface groundwater flow and the contact between groundwater and surface water at the Forsmark site. The surface water system at Forsmark is described with the one-dimensional 'channel flow' modelling tool MIKE 11, which is fully and dynamically integrated with MIKE SHE. The MIKE SHE model was updated with data from the F2.3 data freeze. The main updates concerned the geological description of the saturated zone and the time series data on water levels and surface water discharges. The time series data used as input data and for calibration and validation was extended until the Forsmark 2.3 data freeze (March 31, 2007). The present work can be subdivided into the following four parts: 1. Update of the numerical flow model. 2. Sensitivity analysis and calibration of the model parameters. 3. Validation of the calibrated model, followed by evaluation and identification of discrepancies between measurements and model results. 4. Additional sensitivity analysis and calibration in order to resolve the problems identified in point three above. The main actions taken during the calibration can be summarised as follows: 1. The potential evapotranspiration was reduced in order to reach

  17. Compilation of data used for the analysis of the geological and hydrogeological DFN models. Site descriptive modelling SDM-Site Laxemar

    International Nuclear Information System (INIS)

    Hermanson, Jan; Fox, Aaron; Oehman, Johan; Rhen, Ingvar

    2008-08-01

    This report provides an overview and compilation of the various data that constitutes the basis for construction of the geological and hydrogeological discrete feature network (DFN) models as part of model version SDM-Site Laxemar. This includes a review of fracture data in boreholes and in outcrop. Furthermore, the basis for the construction of lineament maps is given as well as a review of the hydraulic test data from cored and percussion-drilled boreholes. An emphasis is put on graphical representation of borehole logs in the form of composites of geological, hydrogeological and even hydrogeochemical data in the case of cored boreholes. One major contribution is a compilation of characteristics of minor local deformation zones (MDZs) identified in cored boreholes. Basic orientation data and fracture intensity data are presented as a function of depth for individual boreholes. The coupling between hydrogeological data and geological data is further refined in plots of Posiva flow log (PFL) data vs. geological single hole interpretation data

  18. Numerical modelling of solute transport at Forsmark with MIKE SHE. Site descriptive modelling SDM-Site Forsmark

    Energy Technology Data Exchange (ETDEWEB)

    Gustafsson, Lars-Goeran; Sassner, Mona (DHI Sverige AB, Stockholm (Sweden)); Bosson, Emma (Swedish Nuclear Fuel and Waste Management Co., Stockholm (Sweden))

    2008-12-15

    The Swedish Nuclear Fuel and Waste Management Company (SKB) is performing site investigations at two different locations in Sweden, referred to as the Forsmark and Laxemar areas, with the objective of siting a final repository for high-level radioactive waste. Data from the site investigations are used in a variety of modelling activities. This report presents model development and results of numerical transport modelling based on the numerical flow modelling of surface water and near-surface groundwater at the Forsmark site. The numerical modelling was performed using the modelling tool MIKE SHE and is based on the site data and conceptual model of the Forsmark areas. This report presents solute transport applications based on both particle tracking simulations and advection-dispersion calculations. The MIKE SHE model is the basis for the transport modelling presented in this report. Simulation cases relevant for the transport from a deep geological repository have been studied, but also the pattern of near surface recharge and discharge areas. When the main part of the modelling work presented in this report was carried out, the flow modelling of the Forsmark site was not finalised. Thus, the focus of this work is to describe the sensitivity to different transport parameters, and not to point out specific areas as discharge areas from a future repository (this is to be done later, within the framework of the safety assessment). In the last chapter, however, results based on simulations with the re-calibrated MIKE SHE flow model are presented. The results from the MIKE SHE water movement calculations were used by cycling the calculated transient flow field for a selected one-year period as many times as needed to achieve the desired simulation period. The solute source was located either in the bedrock or on top of the model. In total, 15 different transport simulation cases were studied. Five of the simulations were particle tracking simulations, whereas the rest

  19. Meteorological, hydrological and hydrogeological monitoring data and near-surface hydrogeological properties data from Laxemar-Simpevarp. Site descriptive modelling SDM-Site Laxemar

    Energy Technology Data Exchange (ETDEWEB)

    Werner, Kent (EmpTec, Taeby (Sweden)); Oehman, Johan (Golder Associates AB, Stockholm (Sweden)); Holgersson, Bjoern (SWECO VIAK, Stockholm (Sweden)); Roennback, Kristoffer (Aqualog AB, Goeteborg (Sweden)); Marelius, Fredrick (WSP Sverige, Stockholm (Sweden))

    2008-12-15

    This report presents and analyses meteorological, hydrological and hydrogeological time-series data and near-surface hydrogeological properties data from the Laxemar-Simpevarp area, available in SKB's Sicada database at time of the Laxemar 2.3 data freeze (Aug. 31, 2007). The meteorological data set includes data from two local stations, located on the island of Aespoe and at Plittorp, located further inland. In addition, the data evaluation uses a longer-term data set from 7 surrounding stations, operated by SMHI. As part of this study, a time series is constructed of the water content of snow. According to the data evaluation, the site-average annual precipitation and potential evapotranspiration can be estimated to be on the order of 600 and 535 mm, respectively. In particular, precipitation demonstrates a near-coastal gradient, with less precipitation at the coast compared to areas further inland. The surface-water level data set includes data from 4 lake-level gauging stations and 3 sea-level gauging stations. All lakes are located above sea level, including the near-coastal Lake Soeraa. Hence, no intrusion of sea water to lakes takes place. There is a strong co-variation among the monitored lake-water levels, typically with maxima during spring and minima during late summer and early autumn. Concerning the sea as a hydraulic boundary, the maximum and minimum sea levels (daily averages) during the site-investigation period were -0.52 and 0.71 metres above sea level, respectively, whereas the average sea level was 0.03 metres above sea level (RHB 70). The data set on stream discharge, surface-water temperature and electrical conductivity includes data from 9 discharge-gauging stations in 7 streams. Based on the discharge data, the site-average specific discharge for the years 2005-2007 can be estimated to 165 mm/y, which is within the interval of the estimated long-term average. Overall, discharge-data errors are likely to be small. The hydrogeological

  20. Site description of the SFR area at Forsmark at completion of the site investigation phase. SDM-PSU Forsmark

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2013-05-15

    The site descriptive model (SDM) presented in this report is an integrated model for bedrock geology, rock mechanics, bedrock hydrogeology and bedrock hydrogeochemistry of the site investigated in the SFR extension project (PSU). A description of the surface system is also included in the report. However, the surface system is not integrated with the other disciplines as new data regarding the surface system will not be available until after the completion of SDM-PSU. It is noted that SDM-PSU does not include all disciplines handled in SDM-Site Forsmark (SKB 2008b), the focus is to produce a site description that meets the needs of the SFR extension project. The overall objective of the SFR extension project is to have the application for the extension ready by 2013. This report presents an integrated site model incorporating the historic data acquired from the investigations for and construction of the existing SFR facility (1980-1986), as well as from the recent investigations for the planned extension of SFR (2008-2009). It also provides a summary of the abundant underlying data and the discipline-specific models that support the integrated site model. The description relies heavily on background reports concerning detailed data analyses and modelling in the different disciplines. It is noteworthy that the investigations conducted during the SFR extension project were guided by the choice of site prior to the investigations, which was based on the experience gained during the construction of the existing SFR facility.

  1. Site description of the SFR area at Forsmark at completion of the site investigation phase. SDM-PSU Forsmark

    International Nuclear Information System (INIS)

    2013-05-01

    The site descriptive model (SDM) presented in this report is an integrated model for bedrock geology, rock mechanics, bedrock hydrogeology and bedrock hydrogeochemistry of the site investigated in the SFR extension project (PSU). A description of the surface system is also included in the report. However, the surface system is not integrated with the other disciplines as new data regarding the surface system will not be available until after the completion of SDM-PSU. It is noted that SDM-PSU does not include all disciplines handled in SDM-Site Forsmark (SKB 2008b), the focus is to produce a site description that meets the needs of the SFR extension project. The overall objective of the SFR extension project is to have the application for the extension ready by 2013. This report presents an integrated site model incorporating the historic data acquired from the investigations for and construction of the existing SFR facility (1980-1986), as well as from the recent investigations for the planned extension of SFR (2008-2009). It also provides a summary of the abundant underlying data and the discipline-specific models that support the integrated site model. The description relies heavily on background reports concerning detailed data analyses and modelling in the different disciplines. It is noteworthy that the investigations conducted during the SFR extension project were guided by the choice of site prior to the investigations, which was based on the experience gained during the construction of the existing SFR facility

  2. SRP Baseline Hydrogeologic Investigation, Phase 3

    Energy Technology Data Exchange (ETDEWEB)

    Bledsoe, H.W.

    1988-08-01

    The SRP Baseline Hydrogeologic Investigation was implemented for the purpose of updating and improving the knowledge and understanding of the hydrogeologic systems underlying the SRP site. Phase III, which is discussed in this report, includes the drilling of 7 deep coreholes (sites P-24 through P-30) and the installation of 53 observation wells ranging in depth from approximately 50 ft to more than 970 ft below the ground surface. In addition to the collection of geologic cores for lithologic and stratigraphic study, samples were also collected for the determination of physical characteristics of the sediments and for the identification of microorganisms.

  3. Powder XRD investigations on dotriacontane in mixtures: Phase ...

    Indian Academy of Sciences (India)

    Abstract. Powder XRD investigations on dotriacontane-decane and dotriacontane-decanol mixtures are made. Phase strength, phase separation and formation of superlattices are discussed. The role of tunnel-like defects is considered.

  4. Emplacement mechanisms and structural influences of a younger granite intrusion into older wall rocks - a principal study with application to the Goetemar and Uthammar granites. Site-descriptive modelling SDM-Site Laxemar

    Energy Technology Data Exchange (ETDEWEB)

    Cruden, Alexander R. (Dept. of Geology, Univ. of Toronto (Canada))

    2008-12-15

    The c. 1.80 Ga old bedrock in the Laxemar-Simpevarp area, which is the focus of the site investigation at Oskarshamn, is dominated by intrusive rocks belonging to the c. 1.86-1.65 Ga Transscandinavian Igneous Belt (TIB). However, the site investigation area is situated in between two c. 1.45 Ga old anorogenic granites, the Goetemar granite in the north and the Uthammar granite in the south. This study evaluates the emplacement mechanism of these intrusions and their structural influence on the older bedrock. Field observations and structural measurements indicate that both the Goetemar and the Uthammar granites are discordant and have not imposed any significant ductile deformation on their wall-rocks. The apparent conformity of geological contacts and fabrics in the wall rocks and the southern margin of the Goetemar granite is coincidental and inherited from the pattern of Svecokarelian deformation of the TIB. However, interpretation of regional aeromagnetic data suggests that the granites occur within a broad, NNE-SSW trending linear belt, pointing to deep seated tectonic control on their generation, ascent and emplacement. Thermochronology indicates that the granites were emplaced at depths between 4 and 8 km into brittle wall rocks. The 3-D shape of the Goetemar and Uthammar plutons has been investigated by 2.75D forward modelling of the residual gravity anomalies due to both granites. Both granites are associated with strong residual gravity anomalies of up to -10 mgal. Constraints on the geometry of the plutons at the surface are provided from surface geology maps and several deep boreholes located on or close to the model profiles. A further variable in the gravity modelling is introduced by either allowing the upper contact of the plutons to assume the most suitable orientation to produce the best fit between the modelled and observed gravity ('unconstrained models') or by forcing the near surface orientation of the contacts to be vertical (&apos

  5. Emplacement mechanisms and structural influences of a younger granite intrusion into older wall rocks - a principal study with application to the Goetemar and Uthammar granites. Site-descriptive modelling SDM-Site Laxemar

    International Nuclear Information System (INIS)

    Cruden, Alexander R.

    2008-12-01

    The c. 1.80 Ga old bedrock in the Laxemar-Simpevarp area, which is the focus of the site investigation at Oskarshamn, is dominated by intrusive rocks belonging to the c. 1.86-1.65 Ga Transscandinavian Igneous Belt (TIB). However, the site investigation area is situated in between two c. 1.45 Ga old anorogenic granites, the Goetemar granite in the north and the Uthammar granite in the south. This study evaluates the emplacement mechanism of these intrusions and their structural influence on the older bedrock. Field observations and structural measurements indicate that both the Goetemar and the Uthammar granites are discordant and have not imposed any significant ductile deformation on their wall-rocks. The apparent conformity of geological contacts and fabrics in the wall rocks and the southern margin of the Goetemar granite is coincidental and inherited from the pattern of Svecokarelian deformation of the TIB. However, interpretation of regional aeromagnetic data suggests that the granites occur within a broad, NNE-SSW trending linear belt, pointing to deep seated tectonic control on their generation, ascent and emplacement. Thermochronology indicates that the granites were emplaced at depths between 4 and 8 km into brittle wall rocks. The 3-D shape of the Goetemar and Uthammar plutons has been investigated by 2.75D forward modelling of the residual gravity anomalies due to both granites. Both granites are associated with strong residual gravity anomalies of up to -10 mgal. Constraints on the geometry of the plutons at the surface are provided from surface geology maps and several deep boreholes located on or close to the model profiles. A further variable in the gravity modelling is introduced by either allowing the upper contact of the plutons to assume the most suitable orientation to produce the best fit between the modelled and observed gravity ('unconstrained models') or by forcing the near surface orientation of the contacts to be vertical ('constrained

  6. Lattice investigations of the QCD phase diagram

    Energy Technology Data Exchange (ETDEWEB)

    Guenther, Jana

    2016-12-15

    To understand the physics in the early universe as well as in heavy ion collisions a throughout understanding of the theory of strong interaction, quantum chromodynamics (QCD), is important. Lattice QCD provides a tool to study it from first principles. However due to the sign problem direct simulations with physical conditions are at the moment limited to zero chemical potential. In this thesis I present a circumvention of this problem. We can gain information on the QCD phase diagram and the equation of state from analytical continuation of results extracted from simulations at imaginary chemical potential. The topological susceptibility is very expensive to compute in Lattice QCD. However it provides an important ingredient for the estimation of the axion mass. The axion is a possible candidate for a dark matter, which plays in important role in the understanding of our universe. In this thesis I discuss two techniques that make it possible to determine the topological susceptibility and allow for an estimation of the axion mass. I then use this mass restrain to analyze the idea of an experiment to detect axions with a dielectric mirror.

  7. Lattice investigations of the QCD phase diagram

    International Nuclear Information System (INIS)

    Guenther, Jana

    2016-01-01

    To understand the physics in the early universe as well as in heavy ion collisions a throughout understanding of the theory of strong interaction, quantum chromodynamics (QCD), is important. Lattice QCD provides a tool to study it from first principles. However due to the sign problem direct simulations with physical conditions are at the moment limited to zero chemical potential. In this thesis I present a circumvention of this problem. We can gain information on the QCD phase diagram and the equation of state from analytical continuation of results extracted from simulations at imaginary chemical potential. The topological susceptibility is very expensive to compute in Lattice QCD. However it provides an important ingredient for the estimation of the axion mass. The axion is a possible candidate for a dark matter, which plays in important role in the understanding of our universe. In this thesis I discuss two techniques that make it possible to determine the topological susceptibility and allow for an estimation of the axion mass. I then use this mass restrain to analyze the idea of an experiment to detect axions with a dielectric mirror.

  8. SRP baseline hydrogeologic investigation, Phase 2

    Energy Technology Data Exchange (ETDEWEB)

    Bledsoe, H.W.

    1987-11-01

    As discussed in the program plan for the Savannah River Plant (SRP) Baseline Hydrogeologic Investigation, this program has been implemented for the purpose of updating and improving the current state of knowledge and understanding of the hydrogeologic systems underlying the Savannah River Plant (SRP). The objective of the program is to install a series of observation well clusters (wells installed in each major water bearing formation at the same site) at key locations across the plant site in order to: (1) provide detailed information on the lithology, stratigraphy, and groundwater hydrology, (2) provide observation wells to monitor the groundwater quality, head relationships, gradients, and flow paths.

  9. Investigation into the phase effects in nonlinear hollow waveguides

    CSIR Research Space (South Africa)

    Litvin, IA

    2006-07-01

    Full Text Available Numerical calculations of the phase velocities of collective modes of a hollow waveguide at the Stokes frequency is carried out. The self- imaging of transverse structure of modes superposition (Talbot effect) is investigated. It is shown...

  10. Powder XRD investigations on dotriacontane in mixtures: Phase ...

    Indian Academy of Sciences (India)

    Unknown

    Powder XRD investigations on dotriacontane in mixtures: Phase strength and super lattices. P B SHASHIKANTH and P B V PRASAD*. SR Research Laboratory for Studies in Crystallization Phenomena, 10-1-96,. Mamillaguda, Khammam 507 001, India e-mail: prasadpbv_kmm@sol.net.in. MS received 29 January 2000; ...

  11. Investigating the QCD phase diagram with hadron multiplicities at NICA

    Energy Technology Data Exchange (ETDEWEB)

    Becattini, F. [Universita di Firenze (Italy); INFN, Firenze (Italy); Stock, R. [Goethe University, Frankfurt am Main (Germany)

    2016-08-15

    We discuss the potential of the experimental programme at NICA to investigate the QCD phase diagram and particularly the position of the critical line at large baryon-chemical potential with accurate measurements of particle multiplicities. We briefly review the present status and we outline the tasks to be accomplished both theoretically and the experimentally to make hadronic abundances a sensitive probe. (orig.)

  12. Investigation of phase stability in the scandia-zirconia

    International Nuclear Information System (INIS)

    Grosso, Robson Lopes

    2016-01-01

    In this work, the phase stability of scandia-zirconia (ScSZ) system was investigated by the thermodynamic study of nanoparticles, within the range of 0 to 20 mol% Sc 2 O 3 , and by codoping of ZrO 2 -10 mol% Sc 2 O 3 (10ScSZ) with Dy 2 O 3 and Nb 2 O 5 . The phase stability of ScSZ was evaluated based on thermodynamic data collected by water adsorption microcalorimetry and high temperature oxide melt solution. Nanostructured zirconia-scandia solid solutions were synthesized by coprecipitation method. Thermodynamic data were determined for ScSZ polymorph (monoclinic, tetragonal, cubic, rhombohedral β and γ) found by X-ray diffraction. This systemic work resulted in an unprecedented phase diagram at the nanoscale of particle size-composition. The effects of additives on 10ScSZ were investigated aiming to stabilize the cubic (c) structure at room temperature and to suppress the characteristic cubic-rhombohedral β phase transformation. Compositions were prepared by coprecipitation and solid state reaction. Materials were sintered by conventional and spark plasma sintering. Full stabilization of the cubic phase was attained by 1 mol% Dy 2 O 3 and 0.5 mol% Nb 2 O 5 additions. The smallest Nb 2 O 5 content required for cubic phase stabilization was attributed to liquid phase formation during sintering and to small ionic radius of Nb 5+ . Results of high temperature X-ray diffraction and thermal analysis show suppression of the c-β transformation. Samples containing 0.5 mol% Nb 2 O 5 show total ionic conductivity similar to 10ScSZ without additives within a broad temperature range with high stability during 170 h at 600 °C. (author)

  13. Final Work Plan: Phase I Investigation at Bladen, Nebraska

    Energy Technology Data Exchange (ETDEWEB)

    LaFreniere, Lorraine M. [Argonne National Lab. (ANL), Argonne, IL (United States). Environmental Science Division. Applied Geosciences and Environmental Management Section; Yan, Eugene [Argonne National Lab. (ANL), Argonne, IL (United States). Environmental Science Division

    2014-07-01

    The village of Bladen is a town of population approximately 237 in the northwest part of Webster County, Nebraska, 30 mi southwest of Hastings and 140 mi southwest of Lincoln, Nebraska. In 2000, the fumigant-related compound carbon tetrachloride was detected in public water supply well PWS 68-1, at a trace level. Low-level contamination, below the maximum contamination level (MCL) of 5.0 μg/L, has been detected intermittently in well PWS 68-1 since 2000, including in the last sample taken in July 2013. In 2006, the village installed a new well, PWS 2006-1, that remains free of contamination. Because the carbon tetrachloride found in well PWS 68-1 might be linked to historical use of fumigants containing carbon tetrachloride at grain storage facilities, including its former facility in Bladen, the CCC/USDA is proposing an investigation to (1) delineate the source and extent of the carbon tetrachloride contamination potentially associated with its former facility, (2) characterize pathways and controlling factors for contaminant migration in the subsurface, and (3) establish a basis for estimating potential health and environmental risks. The work will be performed in accordance with the Intergovernmental Agreement established between the NDEQ and the Farm Service Agency of the USDA. The site investigation at Bladen will be implemented in phases, so that data collected and interpretations developed during each phase can be evaluated to determine if a subsequent phase of investigation is warranted and, if warranted, to provide effective guidance for the subsequent investigation activities. This Work Plan identifies the specific technical objectives and defines the scope of work proposed for the Phase I investigation by compiling and evaluating historical data. The proposed investigation activities will be performed on behalf of the CCC/USDA by the Environmental Science Division of Argonne National Laboratory. Argonne is a nonprofit, multidisciplinary research

  14. Phase I Source Investigation, Heckathorn Superfund Site, Richmond, California

    Energy Technology Data Exchange (ETDEWEB)

    Kohn, Nancy P; Evans, Nathan R

    2002-12-18

    This report represents Phase I of a multi-phase approach to a source investigation of DDT at the Heckathorn Superfund Site, Richmond, California, the former site of a pesticide packaging plant, and the adjacent waterway, the Lauritzen Channel. Potential identified sources of contamination were from sloughed material from undredged areas (such as side banks) and from outfall pipes. Objectives of Phase I included the (1) evaluation of pesticide concentrations associated with discharge from outfalls, (2) identification of additional outfalls in the area, (3) identification of type, quantity, and distribution of sediment under the Levin pier, (4) quantification of pesticide concentrations in sediment under the pier, and (5) evaluation of sediment structure and slope stability under the pier. Field operations included the collection of sediment directly from inside the mouths of outfall pipes, when possible, or the deployment of specially designed particle traps where direct sampling was problematic. Passive water samplers were placed at the end of known outfall pipes and analyzed for DDT and other pesticides of concern. Underwater dive surveys were conducted beneath the Levin pier to document type, slope, and thickness of sediment. Samples were collected at locations of interest and analyzed for contaminants. Also sampled was soil from bank areas, which were suspected of potentially contributing to continued DDT contamination of the Lauritzen Channel through erosion and groundwater leaching. The Phase I Source Investigation was successful in identifying significant sources of DDT contamination to Lauritzen Channel sediment. Undredged sediment beneath the Levin pier that has been redistributed to the channel is a likely source. Two outfalls tested bear further investigation. Not as well-defined are the contributions of bank erosional material and groundwater leaching. Subsequent investigations will be based on the results of this first phase.

  15. Investigation of a Novel Optical Phase Demodulator based on Sampling Phase-Locked Loop

    DEFF Research Database (Denmark)

    Zibar, Darko; Johansson, L.A.; Chou, H.F.

    2006-01-01

    A novel phase-locked coherent demodulator, based on a sampling phase-locked loop, is presented and investigated theoretically. The demodulator is capable of operating at high-frequencies, by using optical sampling to downconvert the high-frequency input RF signal to the frequency range...... of the baseband loop. We develop a detailed theoretical model of the (sampling) phase-locked coherent demodulator and perform detailed numerical simulations. The simulation results show that the operation of the sampling demodulator resembles the operation of the baseband demodulator for very short optical pulses (...

  16. Phase space investigation of the lithium amide halides

    Energy Technology Data Exchange (ETDEWEB)

    Davies, Rosalind A. [Hydrogen Storage Chemistry Group, School of Chemistry, University of Birmingham, Edgbaston, Birmingham B15 2TT (United Kingdom); Hydrogen and Fuel Cell Group, School of Chemical Engineering, University of Birmingham, Edgbaston B15 2TT (United Kingdom); Hewett, David R.; Korkiakoski, Emma [Hydrogen Storage Chemistry Group, School of Chemistry, University of Birmingham, Edgbaston, Birmingham B15 2TT (United Kingdom); Thompson, Stephen P. [Diamond Light Source, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0QX (United Kingdom); Anderson, Paul A., E-mail: p.a.anderson@bham.ac.uk [Hydrogen Storage Chemistry Group, School of Chemistry, University of Birmingham, Edgbaston, Birmingham B15 2TT (United Kingdom)

    2015-10-05

    Highlights: • The lower limits of halide incorporation in lithium amide have been investigated. • The only amide iodide stoichiometry observed was Li{sub 3}(NH{sub 2}){sub 2}I. • Solid solutions were observed in both the amide chloride and amide bromide systems. • A 46% reduction in chloride content resulted in a new phase: Li{sub 7}(NH{sub 2}){sub 6}Cl. • New low-chloride phase maintained improved H{sub 2} desorption properties of Li{sub 4}(NH{sub 2}){sub 3}Cl. - Abstract: An investigation has been carried out into the lower limits of halide incorporation in lithium amide (LiNH{sub 2}). It was found that the lithium amide iodide Li{sub 3}(NH{sub 2}){sub 2}I was unable to accommodate any variation in stoichiometry. In contrast, some variation in stoichiometry was accommodated in Li{sub 7}(NH{sub 2}){sub 6}Br, as shown by a decrease in unit cell volume when the bromide content was reduced. The amide chloride Li{sub 4}(NH{sub 2}){sub 3}Cl was found to adopt either a rhombohedral or a cubic structure depending on the reaction conditions. Reduction in chloride content generally resulted in a mixture of phases, but a new rhombohedral phase with the stoichiometry Li{sub 7}(NH{sub 2}){sub 6}Cl was observed. In comparison to LiNH{sub 2}, this new low-chloride phase exhibited similar improved hydrogen desorption properties as Li{sub 4}(NH{sub 2}){sub 3}Cl but with a much reduced weight penalty through addition of chloride. Attempts to dope lithium amide with fluoride ions have so far proved unsuccessful.

  17. Experimental and numerical investigation on two-phase flow instabilities

    Energy Technology Data Exchange (ETDEWEB)

    Ruspini, Leonardo Carlos

    2013-03-01

    Two-phase flow instabilities are experimentally and numerically studied within this thesis. In particular, the phenomena called Ledinegg instability, density wave oscillations and pressure drop oscillations are investigated. The most important investigations regarding the occurrence of two-phase flow instabilities are reviewed. An extensive description of the main contributions in the experimental and analytical research is presented. In addition, a critical discussion and recommendations for future investigations are presented. A numerical framework using a hp-adaptive method is developed in order to solve the conservation equations modelling general thermo-hydraulic systems. A natural convection problem is analysed numerically in order to test the numerical solver. Moreover, the description of an adaptive strategy to solve thermo-hydraulic problems is presented. In the second part of this dissertation, a homogeneous model is used to study Ledinegg, density wave and pressure drop oscillations phenomena numerically. The dynamic characteristics of the Ledinegg (flow excursion) phenomenon are analysed through the simulation of several transient examples. In addition, density wave instabilities in boiling and condensing systems are investigated. The effects of several parameters, such as the fluid inertia and compressibility volumes, on the stability limits of Ledinegg and density wave instabilities are studied, showing a strong influence of these parameters. Moreover, the phenomenon called pressure drop oscillations is numerically investigated. A discussion of the physical representation of several models is presented with reference to the obtained numerical results. Finally, the influence of different parameters on these phenomena is analysed. In the last part, an experimental investigation of these phenomena is presented. The designing methodology used for the construction of the experimental facility is described. Several simulations and a non

  18. Investigation of the optical properties of phase change alloys

    Energy Technology Data Exchange (ETDEWEB)

    Shportko, Konstantin; Kremers, Stephan; Woda, Michael; Welnic, Wojciech; Wuttig, Matthias [Institute of Physics, RWTH University of Technology Aachen (Germany)

    2008-07-01

    Phase change materials (PCM) have a unique potential as materials for an emerging non-volatile electronic memory. The aim of this study is to investigate the permittivity dispersion and dispersion of refractive and extinction indexes of the certain alloys of group V and group VI elements. Reflectance spectra have been measured in the UV-VIS/IR range. The spectra have been simulated using SCOUT software. The thickness of the PCM layer has been determined independently. We have analyzed and compared the difference between the spectra of the amorphous and crystalline phases. Our experiments reveal very remarkable findings. Dispersion of the refractive and extinction indexes of both phases show pronounced contrast. The analysis of computations and experimental data reveal the correlation between local structural changes and optical properties as well as the origin of the optical contrast in these materials. The change in optical properties cannot be attributed to a smearing of transition energies as commonly assumed for amorphous semiconductors: the optical contrast between the two phases can only be explained by significant changes in the transition matrix elements.

  19. An investigation of Hebbian phase sequences as assembly graphs

    Directory of Open Access Journals (Sweden)

    Daniel Gomes Almeida Filho

    2014-04-01

    Full Text Available Hebb proposed that synapses between neurons that fire synchronously are strengthened, forming cell assemblies and phase sequences. The former, on a shorter scale, are ensembles of synchronized cells that function transiently as a closed processing system; the latter, on a larger scale, correspond to the sequential activation of cell assemblies able to represent percepts and behaviors. Nowadays, the recording of large neuronal populations allows for the detection of multiple cell assemblies. Within Hebb’s theory, the next logical step is the analysis of phase sequences. Here we detected phase sequences as consecutive assembly activation patterns, and then analyzed their graph attributes in relation to behavior. We investigated action potentials recorded from the adult rat hippocampus and neocortex before, during and after novel object exploration (experimental periods. Within assembly graphs, each assembly corresponded to a node, and each edge corresponded to the temporal sequence of consecutive node activations. The sum of all assembly activations was proportional to firing rates, but the activity of individual assemblies was not. Assembly repertoire was stable across experimental periods, suggesting that novel experience does not create new assemblies in the adult rat. Assembly graph attributes, on the other hand, varied significantly across behavioral states and experimental periods, and were separable enough to correctly classify experimental periods (Naïve Bayes classifier; maximum AUROCs ranging from 0.55 to 0.99 and behavioral states (waking, slow wave sleep, and rapid eye movement sleep; maximum AUROCs s ranging from 0.64 to 0.98. Our findings agree with Hebb’s view that assemblies correspond to primitive building blocks of representation, nearly unchanged in the adult, while phase sequences are labile across behavioral states and change after novel experience. The results are compatible with a role for phase sequences in behavior

  20. Final report : Phase III targeted investigation, Everest, Kansas.

    Energy Technology Data Exchange (ETDEWEB)

    LaFreniere, L. M.; Environmental Science Division

    2006-01-31

    The Commodity Credit Corporation (CCC), an agency of the U.S. Department of Agriculture (USDA), formerly operated grain storage facilities at two different locations at Everest, Kansas (Figure 1.1). One facility (referred to in this report as the Everest facility) was at the western edge of the city. The second facility (referred to in this report as Everest East) was about 0.5 mi northeast of the town. The CCC/USDA operated these facilities from the early 1950s until the early 1970s, at a time when commercial fumigants containing carbon tetrachloride were in common use by the CCC/USDA and private industry for the preservation of grain in storage. In 1997 the Kansas Department of Health and Environment (KDHE) sampled several domestic drinking water and non-drinking water wells in the Everest area as part of the CCC/USDA Private Well Sampling Program. All of the sampled wells were outside the Everest city limits. Carbon tetrachloride contamination was identified at a single domestic drinking water well (the Nigh well, DW06; Figure 1.1) approximately 3/8 mi northwest of the former Everest CCC/USDA grain storage facility. Subsequent KDHE investigations suggested that the contamination in DW06 could be linked to the former use of grain fumigants at the CCC/USDA facility. For this reason, the CCC/USDA is conducting a phased environmental study to determine the source and extent of the carbon tetrachloride contamination at Everest and to identify potential remedial options. The studies are being performed by the Environmental Research Division of Argonne National Laboratory. Two phases of investigation were completed previously; this report presents the findings of the targeted Phase III investigation at Everest.

  1. Investigating Earth shadowing effect with DAMA/LIBRA-phase1

    Energy Technology Data Exchange (ETDEWEB)

    Bernabei, R.; Belli, P.; D' Angelo, S.; Di Marco, A. [Universita di Roma ' ' Tor Vergata' ' , Dipt. di Fisica, Rome (Italy); INFN, sez. Roma ' ' Tor Vergata' ' , Rome (Italy); Montecchia, F. [Universita di Roma ' ' Tor Vergata' ' , Dipt. di Fisica, Rome (Italy); INFN, sez. Roma ' ' Tor Vergata' ' , Rome (Italy); Universita di Roma ' ' Tor Vergata' ' , Dipt. di Ingegneria Civile e Ingegneria Informatica, Rome (Italy); D' Angelo, A.; Incicchitti, A. [Universita di Roma ' ' La Sapienza' ' , Dipt. di Fisica, Rome (Italy); INFN, sez. Roma, Rome (Italy); Cappella, F.; Caracciolo, V.; Cerulli, R. [INFN, Laboratori Nazionali del Gran Sasso, Assergi (Italy); Dai, C.J.; He, H.L.; Kuang, H.H.; Ma, X.H.; Sheng, X.D.; Wang, R.G. [Chinese Academy of Sciences, Key Laboratory of Particle Astrophysics, Institute of High Energy Physics, Beijing (China); Ye, Z.P. [Chinese Academy of Sciences, Key Laboratory of Particle Astrophysics, Institute of High Energy Physics, Beijing (China); University of Jing Gangshan, Ji' an, Jiangxi (China)

    2015-05-15

    In the present paper the results obtained in the investigation of possible diurnal effects for low-energy single-hit scintillation events of DAMA/LIBRA-phase1 (1.04 ton x year exposure) have been analysed in terms of an effect expected in case of dark matter (DM) candidates inducing nuclear recoils and having high cross-section with ordinary matter, which implies low DM local density in order to fulfill the DAMA/LIBRA DM annual modulation results. This effect is due to the different Earth depths crossed by those DM candidates during the sidereal day. (orig.)

  2. Spectroscopy investigations of phase transitions in liquid crystals

    Science.gov (United States)

    Pogorelov, Valerii E.; Pinkevich, Igor P.; Estrela-Llopis, Iryna; Bukalo, Vyacheslav

    1998-09-01

    The results of study of nonoriented nematic MBBA structural genesis at different temperature pre-history are reported. The temperature depended transformations of vibrational Raman spectra and their connections with the change of MBBA structure were investigated. Spectral region was 1100-1600 cm-1, temperature interval was from 163 K to 333 K. The method allows to prognosticate structural evolution of MBBA and to identify phase states. In particular it is discovered that in dependence on cooling rate several coexisting fractions may be obtained at region lower than glass transition temperature.

  3. INVESTIGATION OF POLARIZATION PHASE DIFFERENCE RELATED TO FOREST FIELDS CHARACTERIZATIONS

    Directory of Open Access Journals (Sweden)

    M. Majidi

    2013-09-01

    Full Text Available The information content of Synthetic Aperture Radar (SAR data significantly included in the radiometric polarization channels, hence polarimetric SAR data should be analyzed in relation with target structure. The importance of the phase difference between two co-polarized scattered signals due to the possible association between the biophysical parameters and the measured Polarization Phase Difference (PPD statistics of the backscattered signal recorded components has been recognized in geophysical remote sensing. This paper examines two Radarsat-2 images statistics of the phase difference to describe the feasibility of relationship with the physical properties of scattering targets and tries to understand relevance of PPD statistics with various types of forest fields. As well as variation of incidence angle due to affecting on PPD statistics is investigated. The experimental forest pieces that are used in this research are characterized white pine (Pinus strobus L., red pine (Pinus resinosa Ait., jack pine (Pinus banksiana Lamb., white spruce (Picea glauca (Moench Voss, black spruce (Picea mariana (Mill B.S.P., poplar (Populus L., red oak (Quercus rubra L. , aspen and ground vegetation. The experimental results show that despite of biophysical parameters have a wide diversity, PPD statistics are almost the same. Forest fields distributions as distributed targets have close to zero means regardless of the incidence angle. Also, The PPD distribution are function of both target and sensor parameters, but for more appropriate examination related to PPD statistics the observations should made in the leaf-off season or in bands with lower frequencies.

  4. Investigation of the explosion hazards of hydrogen sulphide. Phase II

    International Nuclear Information System (INIS)

    Moen, I.O.

    1986-01-01

    The results of Phase II of an investigation directed towards quantifying the explosive hazards of hydrogen sulphide in air are described. This second and final phase is focussed on flame acceleration until detonation in obstacle environments simulating a heavy water plant. The results of previous experimental tests, both small and large scale, are compiled and summarized and the results of a series of flame acceleration tests are reported. These tests were performed in order to assess the potential for damaging explosions in simulated industrial environments with repeated obstacles. The experimented apparatus consisted of a channel 1.8 m x 1.8 m in cross-section and 15.5 m long. Two obstacle configurations were tested, corresponding to 500 mm or 220 mm diameter tubes mounted across the channel at regular intervals. Tests were performed with acetylene, propane and hydrogen sulphide fuels. The results of numerical simulation are also reported and compared with the observed results. Scaling predictions are also made. The key results are summarized in the main text, and detailed reports covering the various aspects are included in three annexes

  5. Experimental Investigation of Ice Phase Change Material Heat Exchangers

    Science.gov (United States)

    Leimkuehler, Thomas O.; Stephan, Ryan A.

    2012-01-01

    Phase change materials (PCM) may be useful for spacecraft thermal control systems that involve cyclical heat loads or cyclical thermal environments. Thermal energy can be stored in the PCM during peak heat loads or in adverse thermal environments. The stored thermal energy can then be released later during minimum heat loads or in more favorable thermal environments. This can result in a decreased turndown ratio for the radiator and a reduced system mass. The use of water as a PCM rather than the more traditional paraffin wax has the potential for significant mass reduction since the latent heat of formation of water is approximately 70% greater than that of wax. One of the potential drawbacks of using ice as a PCM is its potential to rupture its container as water expands upon freezing. In order to develop a space qualified ice PCM heat exchanger, failure mechanisms must first be understood. Therefore, a methodical experimental investigation has been undertaken to demonstrate and document specific failure mechanisms due to ice expansion in the PCM. A number of ice PCM heat exchangers were fabricated and tested. Additionally, methods for controlling void location in order to reduce the risk of damage due to ice expansion were investigated. This paper presents an overview of the results of this investigation from the past three years.

  6. Investigation of switching region in superlattice phase change memories

    Science.gov (United States)

    Ohyanagi, T.; Takaura, N.

    2016-10-01

    We investigated superlattice phase change memories (PCMs) to clarify which regions were responsible for switching. We observed atomic structures in a superlattice PCM film with a stack of GeTe / Sb2Te3 layers using atomically resolved EDX maps, and we found an intermixed region with three atom species of the Ge, Sb and Te around the top GeTe layer under the top electrode. We also found that a device with a GeTe layer on an Sb2Te3 layer without superlattice structure had the same switching characteristics as a device with a superlattice PCM, that had the same top GeTe layer. We developed and fabricated a modified superlattice PCM that attained ultra low Reset / Set currents under 60 μ A .

  7. Promising investigational drug candidates in phase I and phase II clinical trials for mesothelioma.

    Science.gov (United States)

    Guazzelli, Alice; Bakker, Emyr; Tian, Kun; Demonacos, Constantinos; Krstic-Demonacos, Marija; Mutti, Luciano

    2017-08-01

    Malignant mesothelioma is a rare and lethal malignancy primarily affecting the pleura and peritoneum. Mesothelioma incidence is expected to increase worldwide and current treatments remain ineffective, leading to poor prognosis. Within this article potential targets to improve the quality of life of the patients and assessment of further avenues for research are discussed. Areas covered: This review highlights emerging therapies currently under investigation for malignant mesothelioma with a specific focus on phase I and phase II clinical trials. Three main areas are discussed: immunotherapy (immune checkpoint blockade and cancer vaccines, among others), multitargeted therapy (such as targeting pro-angiogenic genes) and gene therapy (such as suicide gene therapy). For each, clinical trials are described to detail the current or past investigations at phase I and II. Expert opinion: The approach of applying existing treatments from other cancers does not show significant benefit, with the most promising outcome being an increase in survival of 2.7 months following combination of chemotherapy with bevacizumab. It is our opinion that the hypoxic microenvironment, the role of the stroma, and the metabolic status of mesothelioma should all be assessed and characterised to aid in the development of new treatments to improve patient outcomes.

  8. Sealing of investigation boreholes, Phase 4 - Final report

    Energy Technology Data Exchange (ETDEWEB)

    Pusch, Roland [Drawrite AB, Luleaa Technical University, Luleaa (Sweden); Ramqvist, Gunnar [El-Tekno AB, Figeholm (Sweden); Bockgaard, Niclas [Golder Associates, Goeteborg (Sweden); Ekman, Lennart [LE Geokonsult AB, Baelinge (Sweden)

    2011-09-15

    The report describes the outcome of Phase 4 of the project 'Sealing of investigation boreholes', which deals with 1) characterization and planning of borehole sealing, 2) performance and quality assessment, 3) sealing of large diameter holes, and 4) interaction of clay and concrete plugs. A specific goal was to find ways to characterize, plan and seal of boreholes so that their impact on the overall hydraulic performance of the repository rock can predicted and controlled. The work comprised selection of representative 'reference holes' at the Laxemar and Forsmark sites for development of a general programme for planning and simulating implementation of borehole plugging campaigns, considering also cost issues. A second aim was to define and quantify the role of seals in the reference holes for finding out how important sealing really is. A third was to test a practical way to seal large diameter boreholes and a fourth to find out how concrete matures and performs in contact with smectite clay. The study demonstrated, in conclusion, the need for developing techniques for preparing deep boreholes before lasting seals are installed in them, since poor sealing can short-circuit hydraulically important fracture zones intersected by the holes. The practically oriented sealing activities showed that the technique developed for tight sealing of large-diameter boreholes is practical and feasible. The issue of chemical stability was investigated by testing the performance and constitution of a plug consisting of CBI concrete in contact with smectite-rich seals for almost three years. This study showed that none of them underwent substantial degradation in this period of time, but chemical reactions and thereby generated changes in physical behaviour of the plug components had taken place, particularly in the clay. The rate of degradation is, however, not yet known. It was concluded from this study that it is suitable to carry out a corresponding

  9. Sealing of investigation boreholes, Phase 4 - Final report

    International Nuclear Information System (INIS)

    Pusch, Roland; Ramqvist, Gunnar; Bockgaard, Niclas; Ekman, Lennart

    2011-09-01

    The report describes the outcome of Phase 4 of the project 'Sealing of investigation boreholes', which deals with 1) characterization and planning of borehole sealing, 2) performance and quality assessment, 3) sealing of large diameter holes, and 4) interaction of clay and concrete plugs. A specific goal was to find ways to characterize, plan and seal of boreholes so that their impact on the overall hydraulic performance of the repository rock can predicted and controlled. The work comprised selection of representative 'reference holes' at the Laxemar and Forsmark sites for development of a general programme for planning and simulating implementation of borehole plugging campaigns, considering also cost issues. A second aim was to define and quantify the role of seals in the reference holes for finding out how important sealing really is. A third was to test a practical way to seal large diameter boreholes and a fourth to find out how concrete matures and performs in contact with smectite clay. The study demonstrated, in conclusion, the need for developing techniques for preparing deep boreholes before lasting seals are installed in them, since poor sealing can short-circuit hydraulically important fracture zones intersected by the holes. The practically oriented sealing activities showed that the technique developed for tight sealing of large-diameter boreholes is practical and feasible. The issue of chemical stability was investigated by testing the performance and constitution of a plug consisting of CBI concrete in contact with smectite-rich seals for almost three years. This study showed that none of them underwent substantial degradation in this period of time, but chemical reactions and thereby generated changes in physical behaviour of the plug components had taken place, particularly in the clay. The rate of degradation is, however, not yet known. It was concluded from this study that it is suitable to carry out a corresponding investigation of the plugs

  10. Investigation of binary solid phases by calorimetry and kinetic modelling

    NARCIS (Netherlands)

    Matovic, M.

    2007-01-01

    The traditional methods for the determination of liquid-solid phase diagrams are based on the assumption that the overall equilibrium is established between the phases. However, the result of the crystallization of a liquid mixture will typically be a non-equilibrium or metastable state of the

  11. HRTEM investigation of phase stability in alumina–zirconia ...

    Indian Academy of Sciences (India)

    Phase stability of nanostructured thin films can be significantly different from the stability of the same materials in bulk form because of the increased contribution from surface and interface effects. Zirconia (ZrO2), stabilized in tetragonal and cubic phases, is a technologically important material and is used for most high ...

  12. Preliminary investigation of liquid phase sintering in ferrous systems

    International Nuclear Information System (INIS)

    Klein, J.

    1975-04-01

    Liquid phase sintering was utilized to achieve, by a simple compaction and sintering procedure involving short times and moderate temperatures, a virtually full dense high carbon Fe:C alloy and high boron Fe:B alloy. Parameters such as powder characteristics and mixing, compacting pressure, heating program and the liquid phase fraction were found to influence the sintered density. The response of the Fe:C alloy to a heat treatment is reported along with preliminary experiments in the iron base ternary system Fe:W:C. Residual porosities observed in microstructures of certain liquid phase sintered compacts were accounted for by a proposed capillary flow of the liquid phase and a local densification competing against an overall densification. Some general recommendations are made for liquid phase sintering of powder aggregates. 15 fig., 7 tables

  13. Experimental Investigation of a Six-Phase Variable Frequency Drive

    Directory of Open Access Journals (Sweden)

    Tadas Lipinskis

    2016-06-01

    Full Text Available Experimental results of a variable frequency drive, consisting of a six-phase voltage source inverter and six-phase asynchronous AC motor are presented in this paper. Frequency converter uses a six-phase space vector PWM scheme created by the author. The voltage forming scheme is implemented in Matlab/Simulink, and logical signals for inverter control are transferred from PC via the National instruments PCI-6024E data acquisition card. Voltages, at which the experimental motor operates at maximum efficiency, were determined experimentally. Motor transitions, when it is operating with one, two, and three failed phase windings are presented, confirming that a six-phase motor can operate with up to three failed windings.

  14. Experimental investigation two phase flow in direct methanol fuel cells

    International Nuclear Information System (INIS)

    Mat, M. D.; Kaplan, Y.; Celik, S.; Oeztural, A.

    2007-01-01

    Direct methanol fuel cells (DMFC) have received many attentions specifically for portable electronic applications since it utilize methanol which is in liquid form in atmospheric condition and high energy density of the methanol. Thus it eliminates the storage problem of hydrogen. It also eliminates humidification requirement of polymeric membrane which is a problem in PEM fuel cells. Some electronic companies introduced DMFC prototypes for portable electronic applications. Presence of carbon dioxide gases due to electrochemical reactions in anode makes the problem a two phase problem. A two phase flow may occur at cathode specifically at high current densities due to the excess water. Presence of gas phase in anode region and liquid phase in cathode region prevents diffusion of fuel and oxygen to the reaction sites thus reduces the performance of the system. Uncontrolled pressure buildup in anode region increases methanol crossover through membrane and adversely effect the performance. Two phase flow in both anode and cathode region is very effective in the performance of DMYC system and a detailed understanding of two phase flow for high performance DMFC systems. Although there are many theoretical and experimental studies available on the DMFC systems in the literature, only few studies consider problem as a two-phase flow problem. In this study, an experimental set up is developed and species distributions on system are measured with a gas chromatograph. System performance characteristics (V-I curves) is measured depending on the process parameters (temperature, fuel ad oxidant flow rates, methanol concentration etc)

  15. Investigation of effect of single phase electrical faults at LOFT

    International Nuclear Information System (INIS)

    Yeates, J.A.

    1978-01-01

    This LTR presents the general basic engineering facts related to an open phase fault in a three phase power system commonly referred to as a single phase condition. It describes the probable results to electrical motors and describes the LOFT system design factors which minimize the likelihood of such a fault occurring at LOFT. It recognizes that the hazard of such a fault is a realistic threat and notes the types of relays designed to provide protection. Recommendations are made to perform a detailed engineering study to determine the most advantageous protective relay design, and to implement such a design by installation of the necessary devices and controls

  16. Investigation of the phase formation from nickel coated nanostructured silicon

    Science.gov (United States)

    Shilyaeva, Yulia I.; Pyatilova, Olga V.; Berezkina, Alexandra Yu.; Sysa, Artem V.; Dudin, Alexander A.; Smirnov, Dmitry I.; Gavrilov, Sergey A.

    2016-12-01

    In this paper, the influence of the conditions of chemical and electrochemical nickel plating of nanostructured silicon and subsequent heat treatment on the phase composition of Si/Ni structures with advanced interface is studied. Nanostructured silicon formed by chemical and electrochemical etching was used for the formation of a developed interphase surface. The resulting Si/Ni samples were analyzed using scanning electron microscopy, energy dispersive X-ray analysis, and X-ray phase analysis. The experiments have revealed the differences in phase composition of the Si/Ni structures obtained by different methods, both before and after heat treatment.

  17. Investigation of alternating-phase focusing for superconducting linacs

    International Nuclear Information System (INIS)

    Sagalovsky, L.; Delayen, J.R.

    1992-01-01

    The paper describes a new model of alternating-phase focusing (APF) dynamics applicable to ion linacs with short independently controlled superconducting cavities. The equations of motion are derived for a cylindrically symmetric electric field represented by a traveling wave with continuous periodic phase modulation. Solutions are obtained and analyzed for both the linear and nonlinear particle motion. Problems of linear stability and overall longitudinal acceptance are solved using standard mathematical techniques for periodic systems; analytical results are obtained. It is shown that the main beam dynamical aspects of APF are adequately described by four parameters; equilibrium synchronous phase, phase modulation amplitude, length of APF period, and incremental energy gain. The model can be applied to study the feasibility of realizing APF in a low-β section of a proton linac. (author). 9 refs., 3 figs

  18. Investigation of binary solid phases by calorimetry and kinetic modelling

    OpenAIRE

    Matovic, M.

    2007-01-01

    The traditional methods for the determination of liquid-solid phase diagrams are based on the assumption that the overall equilibrium is established between the phases. However, the result of the crystallization of a liquid mixture will typically be a non-equilibrium or metastable state of the solid. For a proper description of the crystallization process the equilibrium approach is insufficient and a kinetic approach is actually required. In this work, we show that during slow crystallizatio...

  19. Final report on the surface-based investigation phase (phase 1) at the Mizunami Underground Research Laboratory project

    International Nuclear Information System (INIS)

    Saegusa, Hiromitsu; Matsuoka, Toshiyuki

    2011-03-01

    The Mizunami Underground Research Laboratory (MIU) Project is a comprehensive research project investigating the deep underground environment within crystalline rock being conducted by Japan Atomic Energy Agency at Mizunami City in Gifu Prefecture, central Japan and its role is defined in 'Framework for Nuclear Energy Policy' by Japan Atomic Energy Commission. The MIU Project has three overlapping phases: Surface-based Investigation phase (Phase I), Construction phase (Phase II), and Operation phase (Phase III), with a total duration of 20 years. The overall project goals of the MIU Project from Phase I through to Phase III are: 1) to establish techniques for investigation, analysis and assessment of the deep geological environment, and 2) to develop a range of engineering for deep underground application. During Phase I, the overall project goals were supported by Phase I goals. For the overall project goals 1), the Phase I goals were set to construct models of the geological environment from all surface-based investigation results that describe the geological environment prior to excavation and predict excavation response. For the overall project goals 2), the Phase I goals were set to formulate detailed design concepts and a construction plan for the underground facilities. This report summarizes the Phase I investigation which was completed in March 2005. The authors believe this report will make an important milestone, since this report clarifies how the Phase I goals are achieved and evaluate the future issues thereby direct the research which will be conducted during Phase II. With regard to the overall project goals 1), 'To establish techniques for investigation, analysis and assessment of the deep geological environment,' a step-wise investigation was conducted by iterating investigation, interpretation, and assessment, thereby understanding of geologic environment was progressively and effectively improved with progress of investigation. An optimal

  20. HRTEM investigation of phase stability in alumina–zirconia ...

    Indian Academy of Sciences (India)

    stabilized in tetragonal and cubic phases, is a technologically important material and is used for most high tempera- ... zirconia thin-film multilayers in the as deposited state and annealed up to 1473 K at 2 × 10−5 mbar. Conventional techniques .... On the basis of the above equations it can be clearly stated that in the nm ...

  1. HRTEM investigation of phase stability in alumina–zirconia ...

    Indian Academy of Sciences (India)

    2Department of Physics, PERI Institute of Technology, Chennai 600 048, Tamil Nadu, India. 3Centre for Nanoscience and Nanotechnology, Sathyabama University, Chennai 600 119, Tamil Nadu, India. MS received 3 April 2014; revised 26 June 2014. Abstract. Phase stability of nanostructured thin films can be significantly ...

  2. Investigation of intracavity phase interferometry applied to nano-metrology

    Science.gov (United States)

    Luo, Xuan

    Intracavity phase interferometry is sensing technique developed at UNM, in which a physical quantity to be measured is put as integral part of a mode-locked laser. It relies on the fact that any intracavity phase shift of an intracavity pulse will result in a frequency change of the whole pulse train. The implementations of IPI requires the operation of a mode-locked laser in which two pulses circulate independently, i.e. with no phase coupling between them. IPI has been demonstrated with a variety of laser systems, to detect either non-reciprocal effects (such as rotation, magnetic field), or phase changes that can be made periodic at the repetition rate of the laser cavity. The purpose of this work is to study the feasibility of applying this technique to the measurement of non-periodic (i.e. slow) changes in optical path. The new concept to measure sub-nanometer displacement uses an optoelectronic modulator (EOM) inside the cavity. The operation of the mode-locked laser after insertion of such an element in its cavity is analyzed. Several laser systems have been tried for the implementation of IPI. Two of them are presented in this thesis. The first one is a Nd:YVO4 laser, mode-locked by a multiple quantum wells (MQW) saturable absorber. The presence of a solid state saturable absorber introduced a dead band in the beat note response of the system. A new coupling between group and phase velocity was discovered experimentally, and explained through simulation. This coupling affects negatively the operation of the system, since the repetition rate is no longer a reliable fixed quantity. The coupling could be eliminated by replacing the MQW with a dye jet absorber. A first demonstration of a slow optical path change (in the nm range) was made. The system that appeared at first the most promising is the intracavity optical parametric oscillator (OPO) synchronously pumped by a mode-locked Ti:Sapphire lasers. Bringing the unstable behavior of that laser under control

  3. Superconductivity and other nucleon phases investigated with neutron resonances

    International Nuclear Information System (INIS)

    Rohr, G.H.

    1995-01-01

    The results of application of the Bardeen-Copper-Schrieffer (BCS) theory for determination of the general properties of nuclei are discussed. It is shown that the presence of acoustic waves in nuclides indicated by the regular spacing of neutron resonances is completed with the successful application of the BCS theory to nuclei. From the equations used in the BCS theory the coupling strength between nucleons and phonons can be calculated in very good agreement with that of electrons and phonons in a superconductor. This value together with the lifetime of a phonon complete the properties of the quasi-particles in nuclei. In addition using the level densities at neutron separation energy the critical temperature and the transition from the superconductive to the normal non-interacting nucleon phase is reproduced with a function depending only on the ground state shift of the nucleus. However the normal phase transition is obtained only when the excitation is based on the correlated ground state. 14 refs., 11 figs

  4. Investigation of phase error correction for digital sinusoidal phase-shifting fringe projection profilometry

    Science.gov (United States)

    Ma, S.; Quan, C.; Zhu, R.; Tay, C. J.

    2012-08-01

    Digital sinusoidal phase-shifting fringe projection profilometry (DSPFPP) is a powerful tool to reconstruct three-dimensional (3D) surface of diffuse objects. However, a highly accurate profile is often hindered by nonlinear response, color crosstalk and imbalance of a pair of digital projector and CCD/CMOS camera. In this paper, several phase error correction methods, such as Look-Up-Table (LUT) compensation, intensity correction, gamma correction, LUT-based hybrid method and blind phase error suppression for gray and color-encoded DSPFPP are described. Experimental results are also demonstrated to evaluate the effectiveness of each method.

  5. Investigation on Optimization in Segmentation Phase of Iris Recognition

    Directory of Open Access Journals (Sweden)

    Selvamuthukumaran Shanmugam

    2010-01-01

    Full Text Available In a progressively more digital society, the demandfor secure identification has led to amplified development ofbiometric systems. Iris biometric systems are becoming widelyadopted and accepted as one of the most effective ways topositively identify people. In this paper, the Segmentation phasesof Iris recognition has been examined. The performance of theSegmentation phase could be amplified by the proposedoptimization technique- Optimized Iris Segmentation using SobelEdge Detection. By the proposed method, the overall rank-onerecognition rate of 90% is being achieved which is much betterthan reported accuracies for iris recognition in the literature.Also the proposed approach makes the overall iris recognitionsystem performance by the improvement factor of 10 fold as well.

  6. Theoretical investigation of redox species in condensed phase

    Indian Academy of Sciences (India)

    WINTEC

    Application. The methodologies described above were success- fully used to calculate the absolute free energy of reduction of Plastocyanin in water,7g .... Nital Mehta and Sambhu N Datta. 506. Table 1. Quantum chemical softwares necessary for investigation of a molecule in a medium. Software. Relevant task. Availability.

  7. An NMR Investigation of Phase Structure and Chain Dynamics in the Polyethylene/Montmorillonite Nanocomposites

    Directory of Open Access Journals (Sweden)

    Wei Li

    2013-01-01

    Full Text Available Novel exfoliated and interacted polyethylene (PE/montmorillonite (MMT nanocomposites prepared by in situ polymerization were characterized by solid-state nuclear magnetic resonance (NMR. The phase structure and molecular mobility were investigated by proton and carbon NMR under static and magic-angle spinning (MAS conditions. The results showed that incorporation of MMT layer enhanced the polyethylene crystallinity behavior. The chain mobility of crystalline phase, interphase and amorphous phase was hindered in the nanocomposites. The phase structure and chain dynamics were also investigated upon changing the temperature. The orthorhombic and monoclinic phases were detected according to the 13CP/MAS NMR. Quantitative characterization of the phase structure was also conducted by 13C DP/MAS upon changing the temperature. Finally, the difference in the phase structure and chain dynamics in each phase of PE/nanocomposites was compared based on the NMR results when fiber filler was introduced.

  8. Investigation of some features of ferroelectric phase transition in a liquid-crystal binary system

    International Nuclear Information System (INIS)

    Sarkissyan, A.Ts.; Baghdasaryan, Z.V.; Vardanyan, K.K.

    2000-01-01

    Investigation of some features of the ferroelectric phase transition in a liquid-crystal binary system is carried out. It is shown that in investigated systems the flexoelectric effects are responsible, in basic, for occurrence of the spontaneous polarization

  9. CEMS Investigations of Fe-Silicide Phases Formed by the Method of Concentration Controlled Phase Selection

    International Nuclear Information System (INIS)

    Moodley, M. K.; Bharuth-Ram, K.; Waal, H. de; Pretorius, R.

    2002-01-01

    Conversion electron Moessbauer spectroscopy (CEMS) measurements have been made on Fe-silicide samples formed using the method of concentration controlled phase selection. To prepare the samples a 10 nm layer of Fe 30 M 70 (M=Cr, Ni) was evaporated onto Si(100) surfaces, followed by evaporation of a 60 nm Fe layer. Diffusion of the Fe into the Si substrate and the formation of different Fe-Si phases was achieved by subjecting the evaporated samples to a series of heating stages, which consisted of (a) a 10 min anneal at 800 deg. C plus etch of the residual surface layer, (b) a further 3 hr anneal at 800 deg. C, (c) a 60 mJ excimer laser anneal to an energy density of 0.8 J/cm 2 , and (d) a final 3 hr anneal at 800 deg. C. CEMS measurements were used to track the Fe-silicide phases formed. The CEMS spectra consisted of doublets which, based on established hyperfine parameters, could be assigned to α- or β-FeSi 2 or cubic FeSi. The spectra showed that β-FeSi 2 had formed already at the first annealing stage. Excimer laser annealing resulted in the formation of a phase with hyperfine parameters consistent with those of α-FeSi 2 . A further 3 hr anneal at 800 deg. C resulted in complete reversal to the semiconducting β-FeSi 2 phase.

  10. Theoretical modelling and experimental investigation of single-phase and two-phase flow division at a tee-junction

    International Nuclear Information System (INIS)

    Lemonnier, H.; Hervieu, E.

    1991-01-01

    Phase separation in a tee-junction is modelled in the particular case of bubbly-flow. The model is based on a two-dimensional approach and hence, uses local equations. The first step consists in modelling the single-phase flow in the tee-junction. The free streamline theory is used to predict the flow of the continuous phase. The two recirculation zones which are presented in this case are predicted by the model. The second step consists in predicting the gas bubble paths as a result of the actions of the single-phase flow. Finally, the trajectories of gas bubbles are used to predict the separation characteristics of the tee-junction. Each step of the modelling procedure has been carefully tested by an in-depth experimental investigation. Excellent quantitative agreement is obtained between experimental results and model predictions. Moreover, the phase separation phenomenon is found to be clearly described by the model. (orig.)

  11. Using the Lunar Phases Concept Inventory to Investigate College Students' Pre-instructional Mental Models of Lunar Phases

    Science.gov (United States)

    Lindell, Rebecca S.; Sommer, Steven R.

    2004-09-01

    The Lunar Phases Concept Inventory (LPCI) is a twenty-item multiple-choice inventory developed to aid instructors in assessing the mental models their students utilize when answering questions concerning phases of the moon. Based upon an in-depth qualitative investigation of students' understanding of lunar phases, the LPCI was designed to take advantage of the innovative model analysis theory to probe the different dimensions of students' mental models of lunar phases. As part of a national field test, pre-instructional LPCI data was collected for over 750 students from multiple post-secondary institutions across the United States and Canada. Application of model analysis theory to this data set allowed researchers to probe the different mental models of lunar phases students across the country utilize prior to instruction. Results of this analysis display strikingly similar results for the different institutions, suggesting a potential underlying cognitive framework.

  12. High pressure MHD coal combustors investigation, phase 2

    Science.gov (United States)

    Iwata, H.; Hamberg, R.

    1981-05-01

    A high pressure MHD coal combustor was investigated. The purpose was to acquire basic design and support engineering data through systematic combustion experiments at the 10 and 20 thermal megawatt size and to design a 50 MW/sub t/ combustor. This combustor is to produce an electrically conductive plasma generated by the direct combustion of pulverized coal with hot oxygen enriched vitiated air that is seeded with potassium carbonate. Vitiated air and oxygen are used as the oxidizer, however, preheated air will ultimately be used as the oxidizer in coal fired MHD combustors.

  13. CST receiver tube qualification, Phase 1, Investigation - Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Mack, I.; Rossy, J.-P.

    2010-05-15

    In this report the different application possibilities for concentrated solar thermal (CST) systems are studied. Further, the possible measuring methods for characterising and qualifying the receivers with their embedded absorber tubes are investigated. The investigations show that CST systems can be used as an environmentally friendly alternative to fossil fuels in many applications. The best known one is the generation of electrical power, but concentrated solar energy can also be used for desalination, industrial process heat, and for cooling of buildings. Industrial process heat is a large potential area with temperature in the range of 120 {sup o}C to over 400 {sup o}C. Heat below 400 {sup o}C can be provided by various parabolic trough and Fresnel systems, which are optimised for the temperature required. In order to further increase the usage of CST systems, it is of great importance to provide standards for the qualification and characterisation of the different components of the CST systems. Huge efforts are currently made to define a standard for evacuated receiver tubes. For the characterisation of the black absorber tubes the development is still at the beginning, although the need here is also given. (authors)

  14. Radiogauging to investigate two phase flow. Graduation report

    Energy Technology Data Exchange (ETDEWEB)

    Corten, G.P.

    1992-11-12

    New measuring methods are developed and are tested with the small reactor simulator MIDAS (Mini Dodewaard ASsembly). The purpose of this work is to be able to measure accurately as many different properties of the flow as possible in the coming bigger simulator SIDAS (Simulated Dodewaard ASsembly). In SIDAS the flow around a fuel assembly of the Dutch Dodewaard reactor will be simulated. An extensive evaluation of the gamma detection system showed that the detection system could be simplified strongly. The simplified system is used to measure the radial and axial distribution of the void fraction in the core of MIDAS for three different operating conditions. Two new measuring methods have been developed and tested. A method to estimate the probability density of the void fraction in time. Due to the nonlinear relation between transmission and void fraction the determined average value of the void fraction in general will contain a systematic error. In this investigation it is shown that this error can be maximally 7.5% in MIDAS and maximally 25% in SIDAS. Therefore a new measuring method has been developed in which the true probability density of the void fraction in time is approximated by two different values of the void fraction, each with a certain probability. With this new method firstly the average void fraction can be determined much more precisely and secondly it often can be used to determine the flow pattern. (orig./WL).

  15. Experimental investigations on transient single phase flow through perforated plates

    International Nuclear Information System (INIS)

    Casadei, F.

    1983-01-01

    The transient flow of the coolant through the perforated dip-plate during a HCDA in a LMFBR was simulated in a one-dimensional experimental model. Several experiments with water as fluid and with various perforation ratios of the dip-plate and different initial heights of the fluid head over the dip-plate were run. The pressure drop across the dip-plate and the forces acting on the dip-plate and on the upper plug of the reactor vessel were measured in a wide range of the Reynolds and Strouhal numbers. The flow pattern downstreams the perforated plate was filmed with high-speed cameras. The resistance coefficients for the transient flow of the coolant through the perforated plate were obtained as a function of the acceleration. The forces acting on the upper plug and their time integral were compared with those acting on the dip-plate. Finally, using high-speed film pictures the formation of fluid jets downstream the dip-plate was investigated. (orig.)

  16. Neotectonic investigations in southern Ontario: Prince Edward County. Phase I

    International Nuclear Information System (INIS)

    McFall, G.H.; Allam, A.

    1989-03-01

    This report summarizes the preliminary results of geological and geophysical investigations of possible neotectonic features in Prince Edward County, southern Ontario, made by the Ontario Geological Survey during 1988. Low magnitude seismic events indicative of contemporary stress relief occurred during 1987-88 near Salmon Point and Consecon (M 2.2). These events were located proximal to a major regional fault system crossing Lake Ontario and consisting of the Clarendon-Linden Fault System in New York State and the Salmon River-Picton fault systems in Ontario. Detailed observations were made of regional jointing orientations (predominantly 60 degrees and 125 degrees), erosion of surficial deposits adjacent to open fractures, a local fault displacement (post-glacially), dome structures located at Point Petre, and dissolution/karst terrains in the eastern part of the study area. Excavations of four pop-up structures indicate that three are classical pop-ups and one is atypical in structure. Level transects were conducted across complex structures in the eastern part of the study area. Detailed refraction seismic and resistivity surveys were conducted on pop-up and fault features. Preliminary results indicate that the Picton Fault is a complex zone of fractures with differing bedrock on each side. The central zone of the East Duck Pond pop-up is fractured and may contain variable amounts of water. Overturned and upright folds in the Consecon Quarry located outside of the primary research area were documented and found to be trending in a west-northwest to northwest direction. This fold orientation is compatible both with a glacial shove origin and with the present stress field orientations. Although glacial shove can produce overturned folds, it cannot form upright folds. A regional, tectonic deformation oriented northeasterly is therefore suggested as the causative mechanism

  17. Investigating the phase transformations in starch during gelatinisation

    International Nuclear Information System (INIS)

    Tan, I.; Sopade, P.A.; Halley, P.J.

    2003-01-01

    amylose/amylopectin ratio of the raw starch. It was, therefore, proposed that other structural parameters such as crystallinity, lamellar assembly, water distribution inside the granules plays a critical role in the gelatinisation process. This proposition needs to be fully investigated, and small-angle scattering studies (SANS and SAXS) may provide additional information necessary to understand the mechanisms of gelatinisation and the critical parameters that affect it. In addition, this paper highlights the existing discrepancies among these mechanisms, and need for more in-depth study using advanced and novel techniques. How SANS and SAXS may aid the understanding of starch gelatinisation will also be discussed

  18. Theoretical investigation of the forward phase-matched geometry for degenerate four-wave mixing spectroscopy

    International Nuclear Information System (INIS)

    Reichardt, T.A.; Lucht, R.P.; Danehy, P.M.; Farrow, R.L.

    1998-01-01

    We examine theoretically the degenerate four-wave mixing (DFWM) signal intensities and line shapes obtained with the forward phase-matched geometry in which all beams propagate in the same direction and compare the results to those of the phase-conjugate geometry with counterpropagating pump beams. To examine the forward phase-matched geometry, we modify a theoretical approach used previously to calculate phase-conjugate DFWM signal intensities. This theoretical approach, which involves numerical integration of the time-dependent density-matrix equations, is validated for the forward phase-matched geometry by comparison of our calculated line shapes to both a perturbative solution and to experimental data. This methodology is then used to compare the signal intensities and line shapes obtained with the forward phase-matched geometry and the phase-conjugate geometry in the perturbative (low laser power) and saturated (high laser power) regimes. In the perturbative regime the forward phase-matched signal exhibits less sensitivity to the Doppler linewidth. At pump laser intensities approximately equal to the saturation intensity the signal for the forward phase-matched geometry is stronger than that for the phase-conjugate geometry for primarily Doppler-broadened resonances, assuming the same probe volume for both geometries. These advantages warrant further investigations employing the forward phase-matched configuration for DFWM measurements of gas-phase species. copyright 1998 Optical Society of America

  19. Investigation of the overall transient performance of the industrial two-phase closed loop thermosyphon

    NARCIS (Netherlands)

    Vincent, Charles C.J.; Kok, Jacobus B.W.

    1992-01-01

    The two-phase closed loop thermosyphon is investigated with emphasis on the overall performance in transient operation. The control volume approach is the base of a global analysis describing the motion of vapor and liquid phases of the thermosyphon system in one-dimensional equations. Interfacial

  20. Investigation of the Sequential Rotation Technique and its Application in Phased Arrays

    DEFF Research Database (Denmark)

    Larsen, Niels Vesterdal

    2007-01-01

    This report documents the investigations of the sequential rotation technique in application to phased array antennas. A spherical wave expansion for the far field of sequentially phased arrays is derived for general antenna elements. This model is approximate in that it assumes that the element...

  1. New investigation of phase equilibria in the system Al-Cu-Si.

    Science.gov (United States)

    Ponweiser, Norbert; Richter, Klaus W

    2012-01-25

    The phase equilibria and invariant reactions in the system Al-Cu-Si were investigated by a combination of optical microscopy, powder X-ray diffraction (XRD), differential thermal analysis (DTA) and electron probe micro analysis (EPMA). Isothermal phase equilibria were investigated within two isothermal sections. The isothermal section at 500 °C covers the whole ternary composition range and largely confirms the findings of previous phase diagram investigations. The isothermal section at 700 °C describes phase equilibria only in the complex Cu-rich part of the phase diagram. A new ternary compound τ was found in the region between (Al,Cu)-γ(1) and (Cu,Si)-γ and its solubility range was determined. The solubility of Al in κ-CuSi was found to be extremely high at 700 °C. In contrast, no ternary solubility in the β-phase of Cu-Al was found, although this phase is supposed to form a complete solid solution according to previous phase diagram assessments. Two isopleths, at 10 and 40 at.% Si, were investigated by means of DTA and a partial ternary reaction scheme (Scheil diagram) was constructed, based on the current work and the latest findings in the binary systems Al-Cu and Cu-Si. The current study shows that the high temperature equilibria in the Cu-rich corner are still poorly understood and additional studies in this area would be favorable.

  2. Horonobe Underground Research Laboratory project. Synthesis of phase I investigation 2001-2005. Volume 'geoscientific research'

    International Nuclear Information System (INIS)

    Ota, Kunio; Abe, Hironobu; Kunimaru, Takanori

    2011-03-01

    The Horonobe Underground Research Laboratory (URL) Project is being pursued by the Japan Atomic Energy Agency (JAEA) to enhance the reliability of relevant disposal technologies through investigations of the deep geological environment within the host sedimentary formations at Horonobe in Hokkaido, northern Japan. The project consists of two major research areas, 'Geoscientific Research' and 'R and D on Geological Disposal', and proceeds in three overlapping phases, 'Phase I: Surface-based investigation', 'Phase II: Construction' and 'Phase III: Operation', over a period of 20 years. The present report summarises the results of the Phase I geoscientific research carried out from March 2001 to March 2005. Integration of the results from different disciplines ensures that the Phase I goals have been successfully achieved and identifies key issues that need to be addressed in Phases II and III. More importantly, efforts are made to summarise as many lessons learnt from the Phase I investigations and other technical achievements as possible to form a 'knowledge base' that will reinforce the technical basis for both implementation and the formulation of safety regulations. Based on experiences of selecting the URL area and site in Horonobe Town, important factors that should be taken into consideration in such selection processes and their rationale are demonstrated. In the course of stepwise surface-based investigations, a number of achievements have been made, which can eventually provide examples of integrated methodologies for characterising the sedimentary formations. The relevant surface-based investigation techniques have thus been further developed. The Horonobe URL has been designed based on geoscientific information accumulated during the surface-based investigations and the plans for safe construction and operation of the URL have been defined in a feasible manner. In addition, a variety of environmental measures taken during Phase I have proved to be

  3. Investigation on velocity distribution of TFM and DEM phase in hybrid model of CBFB in mining

    Science.gov (United States)

    Zhang, Tianyu; Feng, Ying; Zhao, Zhening

    2017-05-01

    As a novel model for gas solid flow simulation, the investigation of TFM-DEM hybrid model is far from completely, including mutual interaction of TFM and DEM phase, selection of DEM portion and coherence of the predicted results from both phases. Therefore, in present study, the consistency of velocity distribution between TFM and DEM phase is investigated. The correlation of instantaneous and time-averaged velocity distribution of TFM and DEM phase in specific area in CBFB for mining is studied. And the differences of the axial and radial velocity between the particles of different sizes are discussed. The influence of particle diameter and the ratio of DEM and TFM phase on the correlation of velocity, both instantaneous and time-averaged, are taken into consideration.

  4. Experimental Investigation of Microstructure and Phase Transitions in Ag-Cu-Zn Brazing Alloys

    Science.gov (United States)

    Dimitrijević, Stevan P.; Manasijević, Dragan; Kamberović, Željko; Dimitrijević, Silvana B.; Mitrić, Miodrag; Gorgievski, Milan; Mladenović, Srba

    2018-03-01

    Microstructure and phase transitions of selected brazing alloys from the Ag-Cu-Zn ternary system were investigated. Four ternary alloys with silver content in the compositional range from 25 to 60 wt.% were studied using x-ray diffraction (XRD) and scanning electron microscopy coupled with the energy-dispersive spectroscopy (SEM-EDS). Phase transitions of the investigated alloys were measured using differential scanning calorimetry (DSC). Experimentally obtained results were compared with the results of a thermodynamic calculation of the phase equilibria according to the CALPHAD method. The experiments confirmed the optimized thermodynamic parameters for the calculations from the thermodynamic assessment in literature. Phase compositions, liquidus and solidus temperatures were confirmed by the EDS and DTA methods. Additionally, the calculated solidification paths and predicted phase transformations were in agreement with the SEM images.

  5. Hydrochemistry in surface water and shallow groundwater. Site descriptive modelling SDM-Site Forsmark

    Energy Technology Data Exchange (ETDEWEB)

    Troejbom, Mats (Mopelikan, Norrtaelje (SE)); Soederbaeck, Bjoern (Swedish Nuclear Fuel and Waste Management Co., Stockholm (SE)); Johansson, Per-Olof (Artesia Grundvattenkonsult AB, Taeby (SE))

    2007-10-15

    With a mathematical/statistical approach, a large number of visualisations and models reflect the hydrochemistry in the Forsmark area, with the intention to give an understanding of important processes and factors that affect the hydrochemistry in the surface systems. In order to widen the perspective, all data from the Forsmark 2.2 stage including observations from different levels of the bedrock, as well as hydrological measurements and characterisations of the Quaternary deposits, have been included in the analyses. The purpose of this report is to give a general understanding of the site and to explain observed overall patterns as well as anomalies, and, ultimately, to present a conceptual model that explains the present hydrochemistry in the surface system in the light of the past. The report may also function as a basis for further evaluation and testing of scenarios, and may be regarded as an intermediate step between raw data compilations from the vast SICADA database and specialised expert models. The flat topography and the recent withdrawal of the Baltic Sea due to the isostatic land-uplift are two important factors determining the hydrochemistry in the Forsmark area. Marine remnants in the Quaternary deposits, as well as modern sea water intrusions, are therefore strongly influencing the hydrochemistry, especially in areas at low altitude close to the coast. Large-scale marine gradients in the surface system are consistent with the conceptual model that describes the hydrochemical evolution in a paleo-hydrologic perspective. The Forsmark area is covered by glacial remnants, mostly in the form of a till layer, which was deposited during the Weichselian glaciation and deglaciation. When the ice cover retreated about 11,000 years ago, these deposits were exposed on the sea floor. This till layer is characterized by a rich content of calcite, originating from the sedimentary bedrock of Gaevlebukten about 100 km north of Forsmark. The dissolution of this mineral has a central role in the forming of today's hydrochemistry in surface systems, and probably also on the composition of the dilute, non-brackish, groundwater in the upper parts of the fractured bedrock. The rich supply of calcium and the high alkalinity affects the structure of the whole ecosystem, for example by forming the oligotrophic hardwater lakes which are characteristic for the area. One major issue in the report is if there can be found any indications on deep groundwater discharge in the surface system. According to observations in surface water and shallow groundwater, and to the hydrological/hydrochemical conceptual model, there is probably no ongoing deep discharge into the freshwater surface system. In restricted areas there are, however, indications that relict marine remnants, which also includes deep saline signatures, prevail in the groundwater at relatively shallow depths in the Quaternary deposits, but not reach the surface due to the downwards directed groundwater flow pattern that generally prevail in the area. This hydrochemical pattern could according to the conceptual model probably be explained by influence from marine remnants formed under a previous hydrological regime and these signatures are preserved because of stagnant conditions in some areas

  6. The terrestrial ecosystems at Forsmark and Laxemar-Simpevarp. Site descriptive modelling SDM site

    International Nuclear Information System (INIS)

    Loefgren, Anders

    2008-12-01

    This report describes the terrestrial ecosystems in the Forsmark and Laxemar-Simpevarp areas by summarizing ecological data and data from disciplines such as hydrology, quaternary geology and chemistry. The description therefore includes a number of different processes that drive element fluxes in the ecosystems, such as net primary production, heterotrophic respiration, transpiration, and horizontal transport from land to streams and lakes. Moreover, the human appropriation of the landscape is described with regard to land use and potential and actual utilization of food resources both today and in a historical perspective

  7. Hydrochemistry in surface water and shallow groundwater. Site descriptive modelling SDM-Site Forsmark

    International Nuclear Information System (INIS)

    Troejbom, Mats; Soederbaeck, Bjoern; Johansson, Per-Olof

    2007-10-01

    With a mathematical/statistical approach, a large number of visualisations and models reflect the hydrochemistry in the Forsmark area, with the intention to give an understanding of important processes and factors that affect the hydrochemistry in the surface systems. In order to widen the perspective, all data from the Forsmark 2.2 stage including observations from different levels of the bedrock, as well as hydrological measurements and characterisations of the Quaternary deposits, have been included in the analyses. The purpose of this report is to give a general understanding of the site and to explain observed overall patterns as well as anomalies, and, ultimately, to present a conceptual model that explains the present hydrochemistry in the surface system in the light of the past. The report may also function as a basis for further evaluation and testing of scenarios, and may be regarded as an intermediate step between raw data compilations from the vast SICADA database and specialised expert models. The flat topography and the recent withdrawal of the Baltic Sea due to the isostatic land-uplift are two important factors determining the hydrochemistry in the Forsmark area. Marine remnants in the Quaternary deposits, as well as modern sea water intrusions, are therefore strongly influencing the hydrochemistry, especially in areas at low altitude close to the coast. Large-scale marine gradients in the surface system are consistent with the conceptual model that describes the hydrochemical evolution in a paleo-hydrologic perspective. The Forsmark area is covered by glacial remnants, mostly in the form of a till layer, which was deposited during the Weichselian glaciation and deglaciation. When the ice cover retreated about 11,000 years ago, these deposits were exposed on the sea floor. This till layer is characterized by a rich content of calcite, originating from the sedimentary bedrock of Gaevlebukten about 100 km north of Forsmark. The dissolution of this mineral has a central role in the forming of today's hydrochemistry in surface systems, and probably also on the composition of the dilute, non-brackish, groundwater in the upper parts of the fractured bedrock. The rich supply of calcium and the high alkalinity affects the structure of the whole ecosystem, for example by forming the oligotrophic hardwater lakes which are characteristic for the area. One major issue in the report is if there can be found any indications on deep groundwater discharge in the surface system. According to observations in surface water and shallow groundwater, and to the hydrological/hydrochemical conceptual model, there is probably no ongoing deep discharge into the freshwater surface system. In restricted areas there are, however, indications that relict marine remnants, which also includes deep saline signatures, prevail in the groundwater at relatively shallow depths in the Quaternary deposits, but not reach the surface due to the downwards directed groundwater flow pattern that generally prevail in the area. This hydrochemical pattern could according to the conceptual model probably be explained by influence from marine remnants formed under a previous hydrological regime and these signatures are preserved because of stagnant conditions in some areas

  8. Hydrochemistry in surface water and shallow groundwater. Site descriptive modelling SDM-Site Laxemar

    Energy Technology Data Exchange (ETDEWEB)

    Troejbom, Mats (Mopelikan, Norrtaelje (Sweden)); Soederbaeck, Bjoern; Kalinowski, Birgitta (Swedish Nuclear Fuel and Waste Management Co., Stockholm (Sweden))

    2008-10-15

    Based on a mathematical/statistical approach, a large number of visualisations and models reflect the hydrochemistry of the Laxemar-Simpevarp area, with the intention of providing an understanding of important processes and factors that affect the hydrochemistry of the surface systems. In order to widen the perspective, all data from Laxemar stage 2.3, including observations from different levels of the bedrock, as well as hydrological measurements and characterisations of the Quaternary deposits, have been included in the analyses. The purpose of this report is to provide a general understanding of the site and to explain observed overall patterns and anomalies, and ultimately to present a conceptual model that explains the present hydrochemistry of the surface system in the light of the past. The report may also serve as a basis for further evaluation and testing of scenarios, and may be regarded as an intermediate step between raw data compilations from the vast Sicada database and specialised expert models. The topography in the Laxemar-Simpevarp area is characterised by elevated areas covered by thin or no Quaternary deposits, intersected by deep fissure valleys filled with thick sediments. This topography, in combination with the withdrawal of the Baltic Sea due to isostatic land uplift, are two important factors determining the hydrochemistry of the Laxemar-Simpevarp area. Furthermore, marine remnants in the Quaternary deposits influence the hydrochemistry in areas at low elevation close to the coast, whereas higher-lying areas are mostly influenced by atmospheric deposition and weathering processes. The vegetation cover has also great impact on the hydrochemistry of the surface system. Degradation of biogenic carbon generates large numbers of H+ ions, which drive weathering processes in the Quaternary deposits as well as in the upper parts of the bedrock. The present situation in the surface system is a consequence of the palaeohydrological past. In higher elevated areas, meteoric recharge has a great influence on the observed hydrochemistry, which is usually characterised by dilute fresh waters of low ionic strength. In lower areas close to the coast, there are indications of ongoing flushing of marine relicts since the area was covered by sea water. At most locations in the Laxemar-Simpevarp area, this flushing is more or less completed and concentrations of marine ions may be explained by deposition and anthropogenic sources. As much as 2/3 of the Cl input to the surface system has been estimated to originate from anthropogenic sources as road salt. One important question in the hydrochemical evaluation is whether there are any indications of deep groundwater discharge in the surface system. It can be concluded from observations in shallow groundwater that deep groundwater signatures are present in the Quaternary deposits in potential deep discharge areas beneath lakes and brackish bays. On land, no deep signatures have been detected neither in surface water nor in groundwater, which indicates that shallow meteoric recharge/discharge patterns dominate and that potential regional deep discharge is too dilute to be detected in surface water

  9. The limnic ecosystems at Forsmark and Laxemar-Simpevarp. Site descriptive modelling SDM-Site

    International Nuclear Information System (INIS)

    Norden, Sara; Soederbaeck, Bjoern; Andersson, Eva

    2008-11-01

    The overall objective of this report is to provide a thorough description of the limnic ecosystems at both Forsmark and Laxemar-Simpevarp. This information may be used in the Safety Assessment and as a basis for the Environmental Impact Assessment. Three aims were set up for the report: 1) to characterize and describe the limnic ecosystems today and in the past in the Forsmark and Laxemar-Simpevarp areas and compare these ecosystems with limnic ecosystems in other areas; 2) to evaluate and visualize major pools, fluxes and sinks of elements within the limnic ecosystems; and finally 3) to describe human impact on the limnic ecosystems. The report includes a thorough description of the lakes and streams in Forsmark and Laxemar-Simpevarp and covers the following areas: catchment area characteristics, hydrology, climate, sediment characteristics, physical characteristics of streams, habitat distribution in lakes, biotic components, water chemistry, comparisons with other lakes and streams in the region, and a historical description. Ecosystem models for carbon and mass balances for a number of elements have been calculated to further improve the understanding of the lake ecosystems. Important processes for the safety assessment are described and evaluated in the report. The Forsmark regional model area contains more than 20 permanent lakes and pools. All lakes are small and shallow, and are characterized as oligotrophic hardwater lakes. Calcareous soils in the area give rise to high calcium concentrations in the surface water, which in turn leads to high pH and low nutrient concentrations in water as phosphorus often co-precipitates with calcium. The shallow depths and moderate water colour permit photosynthesis in the entire benthic habitat of the lakes, and the bottoms are covered by dense stands of the macroalgae Chara sp. Moreover, many of the lakes also have a thick microbial mat (>10 cm), consisting of cyanobacteria and diatoms, in the benthic habitat. Fish in the lakes are dominated by species resistant to low oxygen concentrations, mainly due to poor oxygen conditions during the winter. The streams in Forsmark are all very small, and long stretches of the streams are dry during summer. The downstream parts of some of the streams may function as passages for migrating fish, and extensive spawning migration between the sea and a downstream lake has been observed. Human activities in the area have affected the limnic ecosystem, and large parts of the streams in the Forsmark area consist of man-made ditches. Moreover, one of the lakes has been lowered and one has been divided into two basins. The ecosystem carbon models for the Forsmark area show that the lakes that contain a microbial mat have larger primary production than respiration, and thus show a positive net ecosystem production (NEP). In lakes that lack a microbial mat, respiration is similar in magnitude as primary production and net ecosystem production is close to zero. Carbon mass balance models for the Forsmark lakes indicate, in accordance with the ecosystem models, that the larger lakes (with a microbial mat) in the area have a positive NEP. However, in contrast to the ecosystem models, the mass balance models indicate that the smaller lakes in the area have negative NEP, regardless of the occurrence of a microbial mat. A low proportion (7-10%) of the carbon incorporated into primary producers in the lake is transported upwards in the food web, and instead most carbon is consumed by bacteria in the form of DOC and POC. The mass balances for a number of elements in Forsmark lakes show that the proportions of different fluxes to and from the lakes are dependent on lake size and position in the catchment, but also on the specific properties of the different elements. The Laxemar-Simpevarp lakes are small and all but one are characterized as brown-water lakes. The lakes have moderate phosphorus concentrations, whereas the concentrations of nitrogen and dissolved organic carbon tend to be high. Because of the brownish water, light penetration is poor and the depth of the photic zone is generally small. In accordance, macrophyte coverage in the lakes is small and biota is dominated by heterotrophic organisms, particularly bacteria. Perch is the predominant fish species in numbers, as well as in weight, in the lakes in the area. Most of the streams in the Laxemar-Simpevarp area are small with mostly calm or slowly flowing water and many of the streams have dry sections in the summer. Most lakes in the Laxemar-Simpevarp area are affected by human activities; the water level in most lakes has been lowered, and one lake, Soeraamagasinet, was originally a sea bay but was dammed in order to ensure freshwater reserves to the nuclear power plant. Water is pumped from Laxemaraan to Soeraamagasinet in order to maintain the available water storage in the lake. Both the carbon ecosystem model and the mass balance for Lake Frisksjoen in Laxemar- Simpevarp indicate a negative NEP, i.e. higher respiration than primary production. The carbon mass balance show that the lake receives large inputs of organic matter and that these inputs are to a large extent mineralized to CO 2 and emitted to the atmosphere. A large part of the carbon influx also contributes to sediment accumulation in the lake. The annual amount of carbon transported to the lake via inflow is of the same magnitude as the internal processes of primary production and consumption, and there is a large probability that carbon entering the lake will be incorporated into the lake food web. A relatively large part of the primary produced carbon (34%) is transported upwards in the food web. Mass balances for a number of elements indicate that, in general, the most important influx of different elements to the lake is via surface water and the most important outflux is via sediment accumulation

  10. The limnic ecosystems at Forsmark and Laxemar-Simpevarp. Site descriptive modelling SDM-Site

    Energy Technology Data Exchange (ETDEWEB)

    Norden, Sara; Soederbaeck, Bjoern (Swedish Nuclear Fuel and Waste Management Co., Stockholm (Sweden)); Andersson, Eva (SWECO, Stockholm (Sweden))

    2008-11-15

    The overall objective of this report is to provide a thorough description of the limnic ecosystems at both Forsmark and Laxemar-Simpevarp. This information may be used in the Safety Assessment and as a basis for the Environmental Impact Assessment. Three aims were set up for the report: 1) to characterize and describe the limnic ecosystems today and in the past in the Forsmark and Laxemar-Simpevarp areas and compare these ecosystems with limnic ecosystems in other areas; 2) to evaluate and visualize major pools, fluxes and sinks of elements within the limnic ecosystems; and finally 3) to describe human impact on the limnic ecosystems. The report includes a thorough description of the lakes and streams in Forsmark and Laxemar-Simpevarp and covers the following areas: catchment area characteristics, hydrology, climate, sediment characteristics, physical characteristics of streams, habitat distribution in lakes, biotic components, water chemistry, comparisons with other lakes and streams in the region, and a historical description. Ecosystem models for carbon and mass balances for a number of elements have been calculated to further improve the understanding of the lake ecosystems. Important processes for the safety assessment are described and evaluated in the report. The Forsmark regional model area contains more than 20 permanent lakes and pools. All lakes are small and shallow, and are characterized as oligotrophic hardwater lakes. Calcareous soils in the area give rise to high calcium concentrations in the surface water, which in turn leads to high pH and low nutrient concentrations in water as phosphorus often co-precipitates with calcium. The shallow depths and moderate water colour permit photosynthesis in the entire benthic habitat of the lakes, and the bottoms are covered by dense stands of the macroalgae Chara sp. Moreover, many of the lakes also have a thick microbial mat (>10 cm), consisting of cyanobacteria and diatoms, in the benthic habitat. Fish in the lakes are dominated by species resistant to low oxygen concentrations, mainly due to poor oxygen conditions during the winter. The streams in Forsmark are all very small, and long stretches of the streams are dry during summer. The downstream parts of some of the streams may function as passages for migrating fish, and extensive spawning migration between the sea and a downstream lake has been observed. Human activities in the area have affected the limnic ecosystem, and large parts of the streams in the Forsmark area consist of man-made ditches. Moreover, one of the lakes has been lowered and one has been divided into two basins. The ecosystem carbon models for the Forsmark area show that the lakes that contain a microbial mat have larger primary production than respiration, and thus show a positive net ecosystem production (NEP). In lakes that lack a microbial mat, respiration is similar in magnitude as primary production and net ecosystem production is close to zero. Carbon mass balance models for the Forsmark lakes indicate, in accordance with the ecosystem models, that the larger lakes (with a microbial mat) in the area have a positive NEP. However, in contrast to the ecosystem models, the mass balance models indicate that the smaller lakes in the area have negative NEP, regardless of the occurrence of a microbial mat. A low proportion (7-10%) of the carbon incorporated into primary producers in the lake is transported upwards in the food web, and instead most carbon is consumed by bacteria in the form of DOC and POC. The mass balances for a number of elements in Forsmark lakes show that the proportions of different fluxes to and from the lakes are dependent on lake size and position in the catchment, but also on the specific properties of the different elements. The Laxemar-Simpevarp lakes are small and all but one are characterized as brown-water lakes. The lakes have moderate phosphorus concentrations, whereas the concentrations of nitrogen and dissolved organic carbon tend to be high. Because of the brownish water, light penetration is poor and the depth of the photic zone is generally small. In accordance, macrophyte coverage in the lakes is small and biota is dominated by heterotrophic organisms, particularly bacteria. Perch is the predominant fish species in numbers, as well as in weight, in the lakes in the area. Most of the streams in the Laxemar-Simpevarp area are small with mostly calm or slowly flowing water and many of the streams have dry sections in the summer. Most lakes in the Laxemar-Simpevarp area are affected by human activities; the water level in most lakes has been lowered, and one lake, Soeraamagasinet, was originally a sea bay but was dammed in order to ensure freshwater reserves to the nuclear power plant. Water is pumped from Laxemaraan to Soeraamagasinet in order to maintain the available water storage in the lake.

  11. The terrestrial ecosystems at Forsmark and Laxemar-Simpevarp. Site descriptive modelling SDM site

    Energy Technology Data Exchange (ETDEWEB)

    Loefgren, Anders (EcoAnalytica, Haegersten (Sweden)) (ed.)

    2008-12-15

    This report describes the terrestrial ecosystems in the Forsmark and Laxemar-Simpevarp areas by summarizing ecological data and data from disciplines such as hydrology, quaternary geology and chemistry. The description therefore includes a number of different processes that drive element fluxes in the ecosystems, such as net primary production, heterotrophic respiration, transpiration, and horizontal transport from land to streams and lakes. Moreover, the human appropriation of the landscape is described with regard to land use and potential and actual utilization of food resources both today and in a historical perspective

  12. Hydrochemistry in surface water and shallow groundwater. Site descriptive modelling SDM-Site Laxemar

    International Nuclear Information System (INIS)

    Troejbom, Mats; Soederbaeck, Bjoern; Kalinowski, Birgitta

    2008-10-01

    Based on a mathematical/statistical approach, a large number of visualisations and models reflect the hydrochemistry of the Laxemar-Simpevarp area, with the intention of providing an understanding of important processes and factors that affect the hydrochemistry of the surface systems. In order to widen the perspective, all data from Laxemar stage 2.3, including observations from different levels of the bedrock, as well as hydrological measurements and characterisations of the Quaternary deposits, have been included in the analyses. The purpose of this report is to provide a general understanding of the site and to explain observed overall patterns and anomalies, and ultimately to present a conceptual model that explains the present hydrochemistry of the surface system in the light of the past. The report may also serve as a basis for further evaluation and testing of scenarios, and may be regarded as an intermediate step between raw data compilations from the vast Sicada database and specialised expert models. The topography in the Laxemar-Simpevarp area is characterised by elevated areas covered by thin or no Quaternary deposits, intersected by deep fissure valleys filled with thick sediments. This topography, in combination with the withdrawal of the Baltic Sea due to isostatic land uplift, are two important factors determining the hydrochemistry of the Laxemar-Simpevarp area. Furthermore, marine remnants in the Quaternary deposits influence the hydrochemistry in areas at low elevation close to the coast, whereas higher-lying areas are mostly influenced by atmospheric deposition and weathering processes. The vegetation cover has also great impact on the hydrochemistry of the surface system. Degradation of biogenic carbon generates large numbers of H + ions, which drive weathering processes in the Quaternary deposits as well as in the upper parts of the bedrock. The present situation in the surface system is a consequence of the palaeohydrological past. In higher elevated areas, meteoric recharge has a great influence on the observed hydrochemistry, which is usually characterised by dilute fresh waters of low ionic strength. In lower areas close to the coast, there are indications of ongoing flushing of marine relicts since the area was covered by sea water. At most locations in the Laxemar-Simpevarp area, this flushing is more or less completed and concentrations of marine ions may be explained by deposition and anthropogenic sources. As much as 2/3 of the Cl input to the surface system has been estimated to originate from anthropogenic sources as road salt. One important question in the hydrochemical evaluation is whether there are any indications of deep groundwater discharge in the surface system. It can be concluded from observations in shallow groundwater that deep groundwater signatures are present in the Quaternary deposits in potential deep discharge areas beneath lakes and brackish bays. On land, no deep signatures have been detected neither in surface water nor in groundwater, which indicates that shallow meteoric recharge/discharge patterns dominate and that potential regional deep discharge is too dilute to be detected in surface water

  13. Colloid transport, retention, and remobilization during two-phase flow: Micro-model investigation and modeling

    NARCIS (Netherlands)

    Zhang, Q.

    2013-01-01

    In this study the transport of colloids in a two-phase fluid system is investigated. In particular, the effects on the interface of two immiscible fluids in steady-state and transient circumstances in a micro-porous network are investigated. The experimental setup is designed consisting of micro

  14. Waste area Grouping 2 Phase I remedial investigation: Sediment and Cesium-137 transport modeling report

    International Nuclear Information System (INIS)

    Clapp, R.B.; Bao, Y.S.; Moore, T.D.; Brenkert, A.L.; Purucker, S.T.; Reece, D.K.; Burgoa, B.B.

    1996-06-01

    This report is one of five reports issued in 1996 that provide follow-up information to the Phase I Remedial Investigation (RI) Report for Waste Area Grouping (WAG) 2 at Oak Ridge National Laboratory (ORNL). The five reports address areas of concern that may present immediate risk to public health at the Clinch River and ecological risk within WAG 2 at ORNL. A sixth report, on groundwater, in the series documenting WAG 2 RI Phase I results were part of project activities conducted in FY 1996. The five reports that complete activities conducted as part of Phase I of the Remedial Investigation (RI) for WAG 2 are as follows: (1) Waste Area Grouping 2, Phase I Task Data Report: Seep Data Assessment, (2) Waste Area Grouping 2, Phase I Task Data Report: Tributaries Data Assessment, (3) Waste Area Grouping 2, Phase I Task Data Report: Ecological Risk Assessment, (4) Waste Area Grouping 2, Phase I Task Data Report: Human Health Risk Assessment, (5) Waste Area Grouping 2, Phase I Task Data Report: Sediment and 137 Cs Transport Modeling In December 1990, the Remedial Investigation Plan for Waste Area Grouping 2 at Oak Ridge National Laboratory was issued (ORNL 1990). The WAG 2 RI Plan was structured with a short-term component to be conducted while upgradient WAGs are investigated and remediated, and a long-term component that will complete the RI process for WAG 2 following remediation of upgradient WAGs. RI activities for the short-term component were initiated with the approval of the Environmental Protection Agency, Region IV (EPA), and the Tennessee Department of Environment and Conservation (TDEC). This report presents the results of an investigation of the risk associated with possible future releases of 137 Cs due to an extreme flood. The results are based on field measurements made during storms and computer model simulations

  15. Investigation of phase coupling phenomena in sustained portion of musical instruments sound

    Science.gov (United States)

    Dubnov, Shlomo; Rodet, Xavier

    2003-01-01

    This work investigates aperiodicities that occur in the sustained portion of a sound of musical instrument played by a human player, due to synchronous versus asynchronous deviations of the partial phases. By using an additive sinusoidal analysis, phases of individual partials are precisely extracted and their correlation statistics and coupling effects are analyzed. It is shown that various musical instruments exhibit different phase coupling characteristics. The effect of phase coupling is compared to analysis by means of higher order statistics and it is shown that both methods are closely mathematically related. Following a detailed analysis of phase coupling for various musical instruments it is suggested that phase coupling is an important characteristic of a sustained portion of sound of individual musical instruments, and possibly even of instrumental families. Interesting differences in phase deviations where found for the flute, trumpet and cello. For the cello, the effect of vibrato is examined by comparing the analysis of a closed string sound played with a natural vibrato to analysis of an open string sound that contains no vibrato. Following, a possible model for phase deviations in the cello is presented and a simulation of phase fluctuations for this model is performed.

  16. Investigating hygroscopic behavior and phase separation of organic/inorganic mixed phase aerosol particles with FTIR spectroscopy

    Science.gov (United States)

    Zawadowicz, M. A.; Cziczo, D. J.

    2013-12-01

    Atmospheric aerosol particles can be composed of inorganic salts, such as ammonium sulfate and sodium chloride, and therefore exhibit hygroscopic properties. Many inorganic salts have very well-defined deliquescence and efflorescence points at which they take up and lose water, respectively. For example, the deliquescence relative humidity of pure ammonium sulfate is about 80% and its efflorescence point is about 35%. This behavior of ammonium sulfate is important to atmospheric chemistry because some reactions, such as the hydrolysis of nitrogen pentoxide, occur on aqueous but not crystalline surfaces. Deliquescence and efflorescence of simple inorganic salt particles have been investigated by a variety of methods, such as IR spectroscopy, tandem mobility analysis and electrodynamic balance. Field measurements have shown that atmospheric aerosol are not typically a single inorganic salt, instead they often contain organic as well as inorganic species. Mixed inorganic/organic aerosol particles, while abundant in the atmosphere, have not been studied as extensively. Many recent studies have focused on microscopy techniques that require deposition of the aerosol on a glass slide, possibly changing its surface properties. This project investigates the deliquescence and efflorescence points, phase separation and ability to exchange gas-phase components of mixed organic and inorganic aerosol using a flow tube coupled with FTIR spectroscopy. Ammonium sulfate aerosol mixed with organic polyols with different O:C ratios, including glycerol, 1,2,6-hexanetriol, 1,4-butanediol and 1,5-pentanediol have been investigated. This project aims to study gas-phase exchange in these aerosol systems to determine if exchange is impacted when phase separation occurs.

  17. A numerical investigation into factors affecting gas and aqueous phase plumes in the subsurface

    Science.gov (United States)

    Thomson, N. R.; Sykes, J. F.; Van Vliet, D.

    1997-10-01

    An investigation into the face and transport of volatile organic compounds (VOCs) in the subsurface requires the consideration of contaminant mass in both the aqueous and soil gas phases. As a result of water/gas phase partitioning, contaminated by partitioning from underlying ground water pollution. Conversely, soil gas can be contaminated by partitioning from underlying ground water VOC plumes. This soil gas and aqueous phase interaction has motivated the popularity of soil gas sampling technology as a method of characterizing ground water VOC contamination. A finite-element-based numerical model was developed to accurately simulate the interaction between the soil gas phase and the aqueous phase. This interaction is complicated since the saturation of the aqueous phase varies dramatically across the capillary fringe. The two-phase flow equations for gas and water are used to describe the flow regime, while the advective-dispersive transport of the VOC is considered in both phases. Dissolution and volatilization from a non-mobile non-aqueous phase liquid is included as a volatile organic contaminant source. A deforming mesh allows the model to accurately track the water table movement, and a Eularian-Lagrangian formulation is used to control some of the numerical difficulties associated with the numerical solution of the advection-dispersion equation. An investigation into diffusion of a VOC from below the water table demonstrated that both the frequency and the magnitude of water table fluctuations have a profound influence on the degree of soil gas contamination. Two-dimensional large-scale, long-term simulations were performed to estimate the aqueous and soil gas phase plumes resulting from an immobilized trichloroethylene residual located in the unsaturated zone. The simulation results indicate that these plumes are very sensitive to the vertical position of the contaminant source. In addition, it was determined that seasonal fluctuations in soil gas VOC

  18. Experimental investigation of Cs 137 distribution in a system of aquatic solution - solid phase - plant

    International Nuclear Information System (INIS)

    Marchiulioniene, D.; Kiponas, D.; Lukshiene, B.

    2005-01-01

    Investigation of Cs 137 accumulation in the plant Lepidium sativum L. (seeds, roots, aboveground part) and in the solid phase from the aquatic solution under laboratory conditions was performed. According to the obtained results, evaluation of Cs 137 distribution in the system aquatic solution - solid phase - plant and transfer of this radionuclide from the root system to the plant aboveground part during the plant growth process was done. (authors)

  19. Employment of a novel ultrasonic method to investigate high pressure phase transitions in oleic acid

    Science.gov (United States)

    Rostocki, A. J.; Siegoczyński, R. M.; Kiełczyński, P.; Szalewski, M.; Balcerzak, A.; Zduniak, M.

    2011-06-01

    In this work, the variation of sound velocity with hydrostatic pressure for oleic acid is evaluated up to 350 MPa. During the measurement, we identified the phase transformation of oleic acid and the presence of the hysteresis of the dependence of sound velocity on pressure. From the performed measurements, it can be seen that the dependence of sound velocity on pressure can be used to investigate phase transformations in natural oils. Ultrasonic waves were excited and detected using piezoelectric LiNbO3(Y-36 cut) 5 MHz transducers. The phase velocity of the longitudinal ultrasonic waves was measured using a cross-correlation method to evaluate the time of flight.

  20. Investigations of binary and ternary phase change alloys for future memory applications

    International Nuclear Information System (INIS)

    Rausch, Pascal

    2012-01-01

    The understanding of phase change materials is of great importance because it enables us to predict properties and tailor alloys which might be even better suitable to tackle challenges of future memory applications. Within this thesis two topics have been approached: on the one hand the understanding of the alloy In 3 Sb 1 Te 2 and on the other hand the so called resistivity drift of amorphous Ge-Sn-Te phase change materials. The main topic covers an in depth discussion of the ternary alloy In 3 Sb 1 Te 2 . At first glance, this alloy does not fit into the established concepts of phase alloys: e.g. the existence of resonant bonding in the crystalline phase is not obvious and the number of p-electrons is very low compared to other phase change alloys. Furthermore amorphous phase change alloys with high indium content are usually not discussed in literature, an exception being the recent work by Spreafico et al. on InGeTe 2 . For the first time a complete description of In 3 Sb 1 Te 2 alloy is given in this work for the crystalline phase, amorphous phase and crystallization process. In addition comparisons are drawn to typical phase change materials like Ge 2 Sb 2 Te 5 /GeTe or prototype systems like AgInTe 2 and InTe. The second topic of this thesis deals with the issue of resistivity drift, i.e. the increase of resistivity of amorphous phase change alloys with aging. This drift effect greatly hampers the introduction of multilevel phase change memory devices into the market. Recently a systematic decrease of drift coefficient with stoichiometry has been observed in our group going from GeTe over Ge 3 Sn 1 Te 4 to Ge 2 Sn 2 Te 4 . These alloys are investigated with respect to constraint theory.

  1. A molecular dynamic investigation for shock induced phase transition of water

    Science.gov (United States)

    Mitra, Nilanjan; Neogi, Anupam

    2015-06-01

    Atomistic equilibrium molecular dynamics (EMD) was carried out to investigate shock induced phase transition of bulk liquid water. Multi-scale shock technique (MSST) was utilized to investigate low (US = 2 . 5km /s) to strong (US = 6 . 5km /s) intensity shock response on an extended flexible three point model up to 100 ns. The thermodynamic pathway of phase transition from liquid water to ice VII was investigated using temporal variation of thermodynamic state variables, power spectrum analyses of O-H bond vibration along with temporal evolution of pair correlation function between O-O, O-H and H-H atoms. Static structure factor along with pair-distribution function extended up to 20 Å was calculated and compared against the ideal ice VII to get information regarding long range ordering. Bragg reflection at different crystal planes were evaluated to investigate percentage of crystallinity of the shocked sample. Specific questions answered in this work involves: What is the exact time frame after the passage of shock at certain intensity in which nucleation of solid phase can be observed? Is it a complete or partial phase transition? Are external nucleators essential for this transformation? What is the percentage of crystallinity of the nucleated phase?

  2. Phase transitions of amorphous solid acetone in confined geometry investigated by reflection absorption infrared spectroscopy.

    Science.gov (United States)

    Shin, Sunghwan; Kang, Hani; Kim, Jun Soo; Kang, Heon

    2014-11-26

    We investigated the phase transformations of amorphous solid acetone under confined geometry by preparing acetone films trapped in amorphous solid water (ASW) or CCl4. Reflection absorption infrared spectroscopy (RAIRS) and temperature-programmed desorption (TPD) were used to monitor the phase changes of the acetone sample with increasing temperature. An acetone film trapped in ASW shows an abrupt change in the RAIRS features of the acetone vibrational bands during heating from 80 to 100 K, which indicates the transformation of amorphous solid acetone to a molecularly aligned crystalline phase. Further heating of the sample to 140 K produces an isotropic solid phase, and eventually a fluid phase near 157 K, at which the acetone sample is probably trapped in a pressurized, superheated condition inside the ASW matrix. Inside a CCl4 matrix, amorphous solid acetone crystallizes into a different, isotropic structure at ca. 90 K. We propose that the molecularly aligned crystalline phase formed in ASW is created by heterogeneous nucleation at the acetone-water interface, with resultant crystal growth, whereas the isotropic crystalline phase in CCl4 is formed by homogeneous crystal growth starting from the bulk region of the acetone sample.

  3. Phase study in Sr-Th-P-O system: Structural and thermal investigations of quaternary compounds

    International Nuclear Information System (INIS)

    Keskar, Meera; Phatak, Rohan; Sali, S.K.; Krishnan, K.; Dahale, N.D.; Kulkarni, N.K.; Kannan, S.

    2011-01-01

    The sub-solidus phase relations in Sr-Th-P-O quaternary system were determined at 1223 K in air. To confirm the formation and stability of reported phases, ternary and quaternary compounds in Sr-Th-O, Sr-P-O, Th-P-O and Sr-Th-P-O systems were synthesized by solid state reactions of SrCO 3 , ThO 2 and NH 4 H 2 PO 4 in desired molar proportions at 1223 K. A pseudo-ternary phase diagram of SrO-ThO 2 -P 2 O 5 system was drawn on the basis of the phase analysis of various phase mixtures and phase fields were established by powder X-ray diffraction. In the phase diagram, three quaternary compounds SrTh(PO 4 ) 2 , SrTh 4 (PO 4 ) 6 and Sr 7 Th(PO 4 ) 6 were identified. When heated in air at 1673 K, these compounds decompose to ThO 2 . Structures of SrTh(PO 4 ) 2 , SrTh 4 (PO 4 ) 6 and Sr 7 Th(PO 4 ) 6 were derived from X-ray powder data using the Rietveld refinement method. Thermal expansion behaviors of SrTh(PO 4 ) 2 , SrTh 4 (PO 4 ) 6 and Sr 7 Th(PO 4 ) 6 were investigated using high-temperature X-ray diffraction in the temperature range of 298-1273 K.

  4. Aespoe Hard Rock Laboratory - feasibility and usefulness of site investigation methods. Experiences from the pre-investigation phase

    International Nuclear Information System (INIS)

    Almen, K.E.; Olsson, Paer; Rhen, I.; Stanfors, R.; Wikberg, P.

    1994-08-01

    One of the main goals set up by SKB for the Aespoe HRL project is to 'test the quality and appropriateness of different methods for characterizing the bedrock with respect to conditions of importance for a final repository'. An extensive investigation programme was carried out during the projects pre-investigation phase that in part was based in experience from SKBs previous site investigations and in part entailed the testing of new or other unestablished methods. Previous technical reports have described the methods that have been used and the results, models and predictions that have been produced. All the methods used are discussed in the present report in terms of how they have contributed in different analysis stages to the total geoscientific characterization of the rock at Aespoe. The usefulness of each method for modelling and prediction in different scales is evaluated, and aspects of the practical execution of the methods under different conditions are discussed. The report sheds light on the importance of dividing large investigation programmes such as this one into suitable stages to get an opportunity to evaluate the results obtained and plan in detail the investigations in the next stage. Furthermore, the way in which the characterization/modelling work in different geometric scales has been done for the different investigation stages is discussed, along with whether this has been found to be a suitable approach. The importance of pursuing an interdisciplinary strategy throughout the pre-investigation process cannot be overemphasized. For the planning, execution, analysis and reporting of the results of the pre-investigations, this has been guaranteed by an organization in which an interdisciplinary group has been in charge of the investigations, together with the project manager. 52 refs, numerous tabs and figs

  5. Experimental investigation of phase equilibria in the Ni-Nb-V ternary system

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Xingjun; Yang, Shuiyuan; Wang, Cuiping [Xiamen Univ. (China). Dept. of Materials Science and Engineering; Xiamen Univ. (China). Fujian Provincial Key Lab. of Materials Genome; Zhang, Xianjie; Jiang, Hengxing; Shi, Zhan [Xiamen Univ. (China). Dept. of Materials Science and Engineering

    2017-09-15

    The phase equilibria of the Ni-Nb-V ternary system at 1000 C and 1200 C were established using electron probe microanalysis, X-ray diffraction and differential scanning calorimetry. The results of the investigation revealed that: (1) The Nb solubility in (Ni) and σ{sup '} phases was less than 10 at.%; (2) A ternary compound τ (NiNbV) was confirmed, in which V had a large solubility; (3) A new liquid region was evident at 1200 C, but was absent at 1000 C; (4) The lattice constants of Ni{sub 3}Nb and Ni{sub 6}Nb{sub 7} phase decreased with increase in V content in the Ni{sub 3}Nb and Ni{sub 6}Nb{sub 7}. The phase equilibria of the Ni-Nb-V ternary system will contribute to its thermodynamic assessment.

  6. High-temperature structural phase transitions in neighborite: a high-resolution neutron powder diffraction investigation

    Science.gov (United States)

    Knight, Kevin S.; Price, G. David; Stuart, John A.; Wood, Ian G.

    2015-01-01

    The nature of the apparently continuous structural phase transition at 1,049 K in the perovskite-structured, MgSiO3 isomorph, neighborite (NaMgF3), from the orthorhombic ( Pbnm) hettotype phase to the cubic () aristotype structure, has been re-investigated using high-resolution, time-of-flight neutron powder diffraction. Using data collected at 1 K intervals close to the nominal phase transition temperature, the temperature dependence of the intensities of superlattice reflections at the M point and the R point of the pseudocubic Brillouin zone indicate the existence of a new intermediate tetragonal phase in space group P4/ mbm, with a narrow phase field extending from ~1,046.5 to ~1,048.5 K, at ambient pressure. Group theoretical analysis shows that the structural transitions identified in this study, Pbnm- P4/ mbm, and P4/ mbm-, are permitted to be second order. The observation of the tetragonal phase resolves the longstanding issue of why the high-temperature phase transition, previously identified as Pbnm-, and which would be expected to be first order under Landau theory, is in fact found to be continuous. Analysis of the pseudocubic shear strain shows it to vary with a critical exponent of 0.5 implying that the phase transition from Pbnm to P4/ mbm is tricritical in character. The large librational modes that exist in the MgF6 octahedron at high temperature, and the use of Gaussian probability density functions to describe atomic displacements, result in apparent bond shortening in the Mg-F distances, making mode amplitude determination an unreliable method for determination of the critical exponent from internal coordinates. Crystal structures are reported for the three phases of NaMgF3 at 1,033 K ( Pbnm), 1,047 K ( P4/ mbm) and 1,049 K ().

  7. Investigations of effect of phase change mass transfer rate on cavitation process with homogeneous relaxation model

    Energy Technology Data Exchange (ETDEWEB)

    He, Zhixia; Zhang, Liang; Saha, Kaushik; Som, Sibendu; Duan, Lian; Wang, Qian

    2017-12-01

    The super high fuel injection pressure and micro size of nozzle orifice has been an important development trend for the fuel injection system. Accordingly, cavitation transient process, fuel compressibility, amount of noncondensable gas in the fuel and cavitation erosion have attracted more attention. Based on the fact of cavitation in itself is a kind of thermodynamic phase change process, this paper takes the perspective of the cavitation phase change mass transfer process to analyze above mentioned phenomenon. The two-phase cavitating turbulent flow simulations with VOF approach coupled with HRM cavitation model and U-RANS of standard k-ε turbulence model were performed for investigations of cavitation phase change mass transfer process. It is concluded the mass transfer time scale coefficient in the Homogenous Relaxation Model (HRM) representing mass transfer rate should tend to be as small as possible in a condition that ensured the solver stable. At very fast mass transfer rate, the phase change occurs at very thin interface between liquid and vapor phase and condensation occurs more focused and then will contribute predictably to a more serious cavitation erosion. Both the initial non-condensable gas in fuel and the fuel compressibility can accelerate the cavitation mass transfer process.

  8. Experimental investigation and thermodynamic calculations of the Bi–In–Ni phase diagram

    Energy Technology Data Exchange (ETDEWEB)

    Premović, Milena [University in Priština, Faculty of Technical Science, Kosovo, Mitrovica (Serbia); Minić, Duško, E-mail: dminic65@open.telekom.rs [University in Priština, Faculty of Technical Science, Kosovo, Mitrovica (Serbia); Manasijević, Dragan [University of Belgrade, Technical Faculty, Bor (Serbia); Ćosović, Vladan [University of Belgrade, Institute of Chemistry, Technology and Metallurgy, Belgrade (Serbia); Živković, Dragana [University of Belgrade, Technical Faculty, Bor (Serbia); Dervišević, Irma [University in Priština, Faculty of Technical Science, Kosovo, Mitrovica (Serbia)

    2015-06-10

    Highlights: • Calculated constitutive binary system based on literature data. • Experimentally determined (DTA) temperatures of phase transformations compared with analytical calculation. • Definition of several vertical sections. • Calculated horizontal section, confirmed by experimental SEM–EDS and XRD method. • Calculated liquidus surface projection and determined invariant reaction occurred in ternary Bi–In–Ni system. - Abstract: Phase diagram of the Bi–In–Ni ternary system was investigated using differential thermal analysis (DTA), scanning electron microscopy (SEM) with energy dispersive spectrometry (EDS), and X-ray powder diffraction (XRD) analysis. Experimentally obtained results were compared with the results of thermodynamic calculation of phase equilibria based on calculation of phase diagram (CALPHAD) method and literature data. Phase transition temperatures of alloys with overall compositions along three selected vertical sections In–Bi{sub 0.8}Ni{sub 0.2}, x(Bi) = 0.6 and Bi–In{sub 0.5}Ni{sub 0.5} were measured by DTA. Liquidus temperatures were experimentally determined and compared with the results of thermodynamic calculation. Identification of coexisting phases in samples equilibrated at 100 °C, 300 °C and 350 °C was carried out using SEM–EDS and XRD methods. The obtained results were compared with the calculated isothermal sections of the Bi–In–Ni ternary system at corresponding temperatures. Calculated liquidus projection and invariant equilibria of the Bi–In–Ni ternary system were presented.

  9. Preliminary applications of the new Neptune two-phase CFD solver to pressurized thermal shock investigations

    International Nuclear Information System (INIS)

    Boucker, M.; Laviaville, J.; Martin, A.; Bechaud, C.; Bestion, D.; Coste, P.

    2004-01-01

    The objective of this communication is to present some preliminary applications to pressurized thermal shock (PTS) investigations of the CFD (Computational Fluid Dynamics) two-phase flow solver of the new NEPTUNE thermal-hydraulics platform. In the framework of plant life extension, the Reactor Pressure Vessel (RPV) integrity is a major concern, and an important part of RPV integrity assessment is related to PTS analysis. In the case where the cold legs are partially filled with steam, it becomes a two-phase problem and new important effects occur, such as condensation due to the Emergency Core Cooling (ECC) injections of sub-cooled water. Thus, an advanced prediction of RPV thermal loading during these transients requires sophisticated two-phase, local scale, 3-dimensional codes. In that purpose, a program has been set up to extend the capabilities of the NEPTUNE two-phase CFD solver. A simple set of turbulence and condensation model for free surface steam-water flow has been tested in simulation of an ECC high pressure injection representing facility, using a full 3-dimensional mesh and the new NEPTUNE solver. Encouraging results have been obtained but it should be noticed that several sources of error can compensate for one another. Nevertheless, the computation presented here allows to be reasonable confident in the use of two-phase CFD in order to carry out refined analysis of two-phase PTS scenarios within the next years

  10. Investigation of snow single scattering properties based on first order Legendre phase function

    Science.gov (United States)

    Eppanapelli, Lavan Kumar; Casselgren, Johan; Wåhlin, Johan; Sjödahl, Mikael

    2017-04-01

    Angularly resolved bidirectional reflectance measurements were modelled by approximating a first order Legendre expanded phase function to retrieve single scattering properties of snow. The measurements from 10 different snow types with known density and specific surface area (SSA) were investigated. A near infrared (NIR) spectrometer was used to measure reflected light above the snow surface over the hemisphere in the wavelength region of 900-1650 nm. A solver based on discrete ordinate radiative transfer (DISORT) model was used to retrieve the estimated Legendre coefficients of the phase function and a correlation between the coefficients and physical properties of different snow types is investigated. Results of this study suggest that the first two coefficients of the first order Legendre phase function provide sufficient information about the physical properties of snow where the latter captures the anisotropic behaviour of snow and the former provides a relative estimate of the single scattering albedo of snow. The coefficients of the first order phase function were compared with the experimental data and observed that both the coefficients are in good agreement with the experimental data. These findings suggest that our approach can be applied as a qualitative tool to investigate physical properties of snow and also to classify different snow types.

  11. A summary of INSITE activities in tracking SKB's spent fuel repository site investigations from 2002-2009 and of advice provided to the regulatory authorities on the status of site understanding at the end of the surface-based investigations

    International Nuclear Information System (INIS)

    Chapman, Neil; Bath, Adrian; Geier, Joel; Ove Stephansson; Tiren, Sven; Tsang, Chin-Fu

    2010-11-01

    SSM and its predecessor SKI employed a team of earth scientists who followed and reviewed SKB's investigations of the potential spent nuclear fuel repository sites at Forsmark and Laxemar. This group was named INSITE (INdependent Site Investigation Tracking and Evaluation) and began its work in 2002 and completed its task with the review of the final versions SKB's site descriptive models, SDM-Site, in 2009. This report is a summary of INSITE's work over the eight-and-a-half year period of the site investigations and the lead-in and the wind-down to the work. It is intended to provide an outline and a record of how INSITE has worked and how its advice was generated and provided to SKI and, latterly, to SSM. Together with all the other documentation generated by INSITE, this report is intended to support the regulatory review of SKB's licence application for a spent nuclear fuel repository

  12. Investigations of binary and ternary phase change alloys for future memory applications

    Energy Technology Data Exchange (ETDEWEB)

    Rausch, Pascal

    2012-09-13

    The understanding of phase change materials is of great importance because it enables us to predict properties and tailor alloys which might be even better suitable to tackle challenges of future memory applications. Within this thesis two topics have been approached: on the one hand the understanding of the alloy In{sub 3}Sb{sub 1}Te{sub 2} and on the other hand the so called resistivity drift of amorphous Ge-Sn-Te phase change materials. The main topic covers an in depth discussion of the ternary alloy In{sub 3}Sb{sub 1}Te{sub 2}. At first glance, this alloy does not fit into the established concepts of phase alloys: e.g. the existence of resonant bonding in the crystalline phase is not obvious and the number of p-electrons is very low compared to other phase change alloys. Furthermore amorphous phase change alloys with high indium content are usually not discussed in literature, an exception being the recent work by Spreafico et al. on InGeTe{sub 2}. For the first time a complete description of In{sub 3}Sb{sub 1}Te{sub 2} alloy is given in this work for the crystalline phase, amorphous phase and crystallization process. In addition comparisons are drawn to typical phase change materials like Ge{sub 2}Sb{sub 2}Te{sub 5}/GeTe or prototype systems like AgInTe{sub 2} and InTe. The second topic of this thesis deals with the issue of resistivity drift, i.e. the increase of resistivity of amorphous phase change alloys with aging. This drift effect greatly hampers the introduction of multilevel phase change memory devices into the market. Recently a systematic decrease of drift coefficient with stoichiometry has been observed in our group going from GeTe over Ge{sub 3}Sn{sub 1}Te{sub 4} to Ge{sub 2}Sn{sub 2}Te{sub 4}. These alloys are investigated with respect to constraint theory.

  13. Experimental investigation of phase equilibria in the Zr-Cu-Ni ternary system

    International Nuclear Information System (INIS)

    Yang, Mujin; Wang, Cuiping; Yang, Shuiyuan; Shi, Zhan; Han, Jiajia; Liu, Xingjun

    2017-01-01

    The phase equilibria in the Zr-Cu-Ni ternary system are investigated combined with X-ray diffraction, electron probe micro-analysis and differential scanning calorimetry. Two isothermal sections of the Zr-Cu-Ni ternary system at 1 000 C and 1 100 C are experimentally established. Most of the binary intermetallic compounds, e.g. Zr 7 Ni 10 , ZrNi, ZrNi 5 , Zr 14 Cu 51 , and Zr 2 Cu 9 , show a remarkable ternary solubility. A new ternary compound named τ 3 (Zr 31.1-30.7 . Cu 28.5-40.3 Ni 40.4-29.0 ) is detected at 1 000 C and dissolved at 1 020 C because the nearby large liquid phase field further expands. The newly determined phase equilibria will provide important information for both thermodynamic assessment and alloy design of Zr-based metallic glass.

  14. Controlled in meso phase crystallization--a method for the structural investigation of membrane proteins.

    Directory of Open Access Journals (Sweden)

    Jan Kubicek

    Full Text Available We investigated in meso crystallization of membrane proteins to develop a fast screening technology which combines features of the well established classical vapor diffusion experiment with the batch meso phase crystallization, but without premixing of protein and monoolein. It inherits the advantages of both methods, namely (i the stabilization of membrane proteins in the meso phase, (ii the control of hydration level and additive concentration by vapor diffusion. The new technology (iii significantly simplifies in meso crystallization experiments and allows the use of standard liquid handling robots suitable for 96 well formats. CIMP crystallization furthermore allows (iv direct monitoring of phase transformation and crystallization events. Bacteriorhodopsin (BR crystals of high quality and diffraction up to 1.3 Å resolution have been obtained in this approach. CIMP and the developed consumables and protocols have been successfully applied to obtain crystals of sensory rhodopsin II (SRII from Halobacterium salinarum for the first time.

  15. Simulation Based Investigation of Focusing Phased Array Ultrasound in Dissimilar Metal Welds

    Directory of Open Access Journals (Sweden)

    Hun-Hee Kim

    2016-02-01

    Full Text Available Flaws at dissimilar metal welds (DMWs, such as reactor coolant systems components, Control Rod Drive Mechanism (CRDM, Bottom Mounted Instrumentation (BMI etc., in nuclear power plants have been found. Notably, primary water stress corrosion cracking (PWSCC in the DMWs could cause significant reliability problems at nuclear power plants. Therefore, phased array ultrasound is widely used for inspecting surface break cracks and stress corrosion cracks in DMWs. However, inspection of DMWs using phased array ultrasound has a relatively low probability of detection of cracks, because the crystalline structure of welds causes distortion and splitting of the ultrasonic beams which propagates anisotropic medium. Therefore, advanced evaluation techniques of phased array ultrasound are needed for improvement in the probability of detection of flaws in DMWs. Thus, in this study, an investigation of focusing and steering phased array ultrasound in DMWs was carried out using a time reversal technique, and an adaptive focusing technique based on finite element method (FEM simulation. Also, evaluation of focusing performance of three different focusing techniques was performed by comparing amplitude of phased array ultrasonic signals scattered from the targeted flaw with three different time delays.

  16. Ternary Phase-Separation Investigation of Sol-Gel Derived Silica from Ethyl Silicate 40

    Science.gov (United States)

    Wang, Shengnan; Wang, David K.; Smart, Simon; Diniz da Costa, João C.

    2015-01-01

    A ternary phase-separation investigation of the ethyl silicate 40 (ES40) sol-gel process was conducted using ethanol and water as the solvent and hydrolysing agent, respectively. This oligomeric silica precursor underwent various degrees of phase separation behaviour in solution during the sol-gel reactions as a function of temperature and H2O/Si ratios. The solution composition within the immiscible region of the ES40 phase-separated system shows that the hydrolysis and condensation reactions decreased with decreasing reaction temperature. A mesoporous structure was obtained at low temperature due to weak drying forces from slow solvent evaporation on one hand and formation of unreacted ES40 cages in the other, which reduced network shrinkage and produced larger pores. This was attributed to the concentration of the reactive sites around the phase-separated interface, which enhanced the condensation and crosslinking. Contrary to dense silica structures obtained from sol-gel reactions in the miscible region, higher microporosity was produced via a phase-separated sol-gel system by using high H2O/Si ratios. This tailoring process facilitated further condensation reactions and crosslinking of silica chains, which coupled with stiffening of the network, made it more resistant to compression and densification. PMID:26411484

  17. Neutron spin-echo investigation of the microemulsion dynamics. in bicontinuous lamellar and droplet phases

    CERN Document Server

    Mihailescu, M; Endo, H; Allgaier, J; Gompper, G; Stellbrink, J; Richter, D; Jakobs, B; Sottmann, T; Faragó, B

    2002-01-01

    Using neutron spin-echo (NSE) spectroscopy in combination with dynamic light scattering (DLS), we performed an extensive investigation of the bicontinuous phase in ternary water-surfactant-oil microemulsions, with extension to lamellar and droplet phases. The dynamical behavior of surfactant monolayers of decyl-polyglycol-ether (C sub 1 sub 0 E sub 4) molecules, or mixtures of surfactant with long amphiphilic block-copolymers of type poly-ethylene propylene/poly-ethylene oxide (PEP-PEO) was studied, under comparable conditions. The investigation techniques provide access to different length scales relative to the characteristic periodicity length of the microemulsion structure. Information on the elastic bending modulus is obtained from the local scale dynamics in view of existing theoretical descriptions and is found to be in accordance with small angle neutron scattering (SANS) studies. Evidence for the modified elastic properties and additional interaction of the amphiphilic layers due to the polymer is mo...

  18. High-pressure fluid-phase equilibria: Experimental methods and systems investigated (2005-2008)

    DEFF Research Database (Denmark)

    Fonseca, José; Dohrn, Ralf; Peper, Stephanie

    2011-01-01

    A review of systems is given, for which experimental high-pressure phase-equilibrium data were published in the period between 2005 and 2008, continuing a series of reviews. To find candidates for articles that are of interest for this survey a three-stage search strategy was used including...... a systematic search of the contents of the 17 most important journals of the field. Experimental methods for the investigation of high-pressure phase equilibria were classified, described and illustrated using examples from articles of the period between 2005 and 2008. For the systems investigated......, the reference, the temperature and pressure range of the data, and the experimental method used for the measurements is given in 54 tables. Vapor–liquid equilibria, liquid–liquid equilibria, vapor–liquid–liquid equilibria, solid–liquid equilibria, solid–vapor equilibria, solid–vapor–liquid equilibria, critical...

  19. Investigation of two-phase transport phenomena in microchannels using a microfabricated experimental structure

    Energy Technology Data Exchange (ETDEWEB)

    Wang Fumin [Mechanical Engineering Department, Stanford University, Room 224, Building 530, Stanford, CA 94305-3030 (United States)]. E-mail: fuminmems@gmail.com; Steinbrenner, Julie E. [Mechanical Engineering Department, Stanford University, Room 224, Building 530, Stanford, CA 94305-3030 (United States); Hidrovo, Carlos H. [Mechanical Engineering Department, Stanford University, Room 224, Building 530, Stanford, CA 94305-3030 (United States); Kramer, Theresa A. [Mechanical Engineering Department, Stanford University, Room 224, Building 530, Stanford, CA 94305-3030 (United States); Lee, Eon Soo [Mechanical Engineering Department, Stanford University, Room 224, Building 530, Stanford, CA 94305-3030 (United States); Vigneron, Sebastien [Mechanical Engineering Department, Stanford University, Room 224, Building 530, Stanford, CA 94305-3030 (United States); Cheng, Ching-Hsiang [Mechanical Engineering Department, Stanford University, Room 224, Building 530, Stanford, CA 94305-3030 (United States); Eaton, John K. [Mechanical Engineering Department, Stanford University, Room 224, Building 530, Stanford, CA 94305-3030 (United States); Goodson, Kenneth E. [Mechanical Engineering Department, Stanford University, Room 224, Building 530, Stanford, CA 94305-3030 (United States)

    2007-07-15

    Microchannels (0.05-1 mm) improve gas routing in proton exchange membrane fuel cells, but add to the complexities of water management. This work microfabricates experimental structures with distributed water injection as well as with heating and temperature sensing capabilities to study water formation and transport. The samples feature optical access to allow visualization and distributed thermometry for investigation of two-phase flow transport phenomena in the microchannels. The temperature evolution along the channel is observed that the temperature downstream of the distributed water injection decreases as the pressure drop increases. As the water injection rate is lower than 200 {mu}l/min, there exists a turning point where temperature increases as the pressure drop increases further. These micromachined structures with integrated temperature sensors and heaters are key to the experimental investigation as well as visualization of two-phase flow and water transport phenomena in microchannels for fuel cell applications.

  20. Two-phase flow in steam turbines: EDF R and D division investigations

    International Nuclear Information System (INIS)

    Laali, A.R.

    1992-05-01

    This report outlines the investigations on wet steam flows in steam turbines. All the softwares developed in the framework of these studies enables analysis of different aspects of these types of flows. The use of two phase codes based on 2 fluid models, which has achieved a sufficient progress, and the integration of the condensation programme in a transonic non stationary code will constitute a second step for these studies, enhancing what has already been achieved in this field

  1. Physical investigation of square cylinder array dynamical response under single-phase cross-flow

    International Nuclear Information System (INIS)

    Longatte, E.; Baj, F.

    2014-01-01

    Fluid structure interaction and flow-induced vibration in square cylinder arrangement under single-phase incompressible laminar cross flow are investigated in the present paper. Dynamic instability governed by damping generation is studied without any consideration about mixing with turbulence effects. Conservative and non-conservative effects are pointed out and dynamical stability limit sensitivity to physical parameters is analyzed. Finally the influence of key physical parameters on fluid solid dynamics interaction is quantified. (authors)

  2. An Investigation of Attenuation, Scattering and Site Effects on Regional Phases.

    Science.gov (United States)

    1981-03-23

    sedimentary sites (circles) relative to hard rock sites (squares) located on the shield or stable platform region of North America. Triangles denote the...resting on granitic or consolidated lower Paleozoic rocks having no more than 50 m of overlying unconsolidated rock cover. All sites not satisfying...investigate amplification of regional phases at sedimentary sites (circles) relative to hard rock sites (squares) located on the shield or stable platform

  3. The possibility of using dc conductivity for investigating phase transition in amorphous semiconductors

    International Nuclear Information System (INIS)

    El-Mously, M.K.; Mina, N.K.

    1985-07-01

    Different formulas have been applied to deduce the effective or the generalized electrical conductivity of double phase systems. These formulas have been revised and fitted to the experimental data of the binary systems amorphous-crystal (a-c) and liquid-crystal (l-c) for pure elementary selenium and selenium doped by different other elements. Both connected medium and statistical mixture theories can be applied depending on the nature of the system under investigation. (author)

  4. Radiative acoustic investigation of metals in the area of structural phase transition

    International Nuclear Information System (INIS)

    Kalinichenko, A.I.; Popov, G.F.

    1989-01-01

    Consideration is given to results of experimental investigations of temperature dependences of Grueneisen parameter (GP) and sound velocity for alloys with the effect of shape memory (Cu-Al-Ni and Ni-Ti) and gadolinium in the region of their structural phase transformations. Effect of thermal and spatial GP nonlinearity on the type of excited acoustic wave, as well as possibility of determining function of GP dependence with respect to nonlinear thermoacoustic response of irradiated substance are discussed

  5. Thermodynamic analysis and phase equilibria investigation in Pb−Zn−Ag system

    Directory of Open Access Journals (Sweden)

    Mitovski Aleksandra M.

    2010-01-01

    Full Text Available Physico-chemical processes that take place during the refining process in the extractive metallurgy of lead, are connected with ternary Pb−Zn−Ag system, which is necessary to study from the theoretical practical and aspects. Such investigation is important from production point of view, because of the phenomena that occur during desilvering of lead which is one of the important stages during lead refining process. Process of lead desilvering binds to ternary system Pb−Zn−Ag, which was the reason for numerous investigations, both from thermodynamic point of view and in terms of testing and determining the phase diagram, bearing in mind the theoretical, and practical importance of knowledge about the processes which are going in investigated system. The paper presents the results of thermodynamic analysis and investigation of phase equilibria of the Pb−Zn−Ag ternary system using the method of thermodynamic predictions and phase diagrams calculations, respectively, and the experimental results of metalography obtained by optical microscopy. Phase diagram of the vertical section Pb−Zn80Ag20 is presented, obtained by CALPHAD calculation methodology, and using PANDAT thermodynamic software, compared to experimental results obtained by DTA analysis. The results show a pronounced break in solubility, which is characteristic for the whole ternary Pb−Zn−Ag system. Also, it can be noticed that the thermodynamic properties follow the behavior of this system, which is expressed through positive deviation of Raoult’s law, pointing to the lack of lead affinity compared to the other two components in the system. The optical microscopy results of the investigated system show the following: - Sample L1 (weight% Pb = 98: the structure of the observed section shows double eutectic (Pbsol+Zn−Agsol which lies in the base of the primary crystals of lead (Pbsol - Samples L2−L5: the structure consists of a dual eutectic (Pbsol+Zn−Agsol and

  6. Hydrogeological and hydrogeochemical investigations in boreholes - Final report of the phase I geochemical investigations of the Stripa groundwaters

    International Nuclear Information System (INIS)

    Nordstroem, D.K.; Carlsson, L.; Fontes, J.C.; Frits, P.; Moser, H.; Olsson, T.

    1985-07-01

    The hydrogeochemical investigations of Phase I of the Stripa Project (1980-1984) have been completed, and the results are presented in this final report. All chemical and isotopic data on the groundwaters from the beginning to the Stripa Project to the present (1977-84) are tabulated an used in the final interpretations. The background geology and hydrology is summarized and updated along with new analyses of the Stripa grantie. Water-rock interactions form a basic framework for the changes in major-element chemistry with depth, including carbonate geochemistry, the fluid-inclusion hypothesis, redox processes, and mineral precipitation. The irregular distribution of chloride suggests channelling is occurring and the effect of thermomechanical perturbations on the groundwater chemistry is documented. Stable and radioactive isotpes provide information of the origin and evolution of the groundwater itself and of several elments within the groundwater. Subsurface production of radionuclides is documented in these investigations, and a general picture of uranium transformations during weathering is presented. One of the primary conclusions reached in these studies is that different dissolved constituents will provide different residence times because they have different origins and different evolutionary histories that may or may not be related to the overall evolution of the groundwater itself. (author)

  7. Theoretical Investigations of Si-Ge Alloys in P42/ncm Phase: First-Principles Calculations

    Directory of Open Access Journals (Sweden)

    Zhenyang Ma

    2017-05-01

    Full Text Available The structural, mechanical, anisotropic, electronic and thermal properties of Si, Si0.667Ge0.333, Si0.333Ge0.667 and Ge in P42/ncm phase are investigated in this work. The calculations have been performed with an ultra-soft pseudopotential by using the generalized gradient approximation and local density approximation in the framework of density functional theory. The achieved results for the lattice constants and band gaps of P42/ncm-Si and P42/ncm-Ge in this research have good accordance with other results. The calculated elastic constants and elastic moduli of the Si, Si0.667Ge0.333, Si0.333Ge0.667 and Ge in P42/ncm phase are better than that of the Si, Si0.667Ge0.333, Si0.333Ge0.667 and Ge in P42/mnm phase. The Si, Si0.667Ge0.333, Si0.333Ge0.667 and Ge in P42/ncm phase exhibit varying degrees of mechanical anisotropic properties in Poisson’s ratio, shear modulus, Young’s modulus, and universal anisotropic index. The band structures of the Si, Si0.667Ge0.333, Si0.333Ge0.667 and Ge in P42/ncm phase show that they are all indirect band gap semiconductors with band gap of 1.46 eV, 1.25 eV, 1.36 eV and 1.00 eV, respectively. In addition, we also found that the minimum thermal conductivity κmin of the Si, Si0.667Ge0.333, Si0.333Ge0.667 and Ge in P42/ncm phase exhibit different degrees of anisotropic properties in (001, (010, (100 and (01¯0 planes.

  8. Phase sensitive molecular dynamics of self-assembly glycolipid thin films: A dielectric spectroscopy investigation

    Science.gov (United States)

    Velayutham, T. S.; Ng, B. K.; Gan, W. C.; Majid, W. H. Abd.; Hashim, R.; Zahid, N. I.; Chaiprapa, Jitrin

    2014-08-01

    Glycolipid, found commonly in membranes, is also a liquid crystal material which can self-assemble without the presence of a solvent. Here, the dielectric and conductivity properties of three synthetic glycolipid thin films in different thermotropic liquid crystal phases were investigated over a frequency and temperature range of (10-2-106 Hz) and (303-463 K), respectively. The observed relaxation processes distinguish between the different phases (smectic A, columnar/hexagonal, and bicontinuous cubic Q) and the glycolipid molecular structures. Large dielectric responses were observed in the columnar and bicontinuous cubic phases of the longer branched alkyl chain glycolipids. Glycolipids with the shortest branched alkyl chain experience the most restricted self-assembly dynamic process over the broad temperature range studied compared to the longer ones. A high frequency dielectric absorption (Process I) was observed in all samples. This is related to the dynamics of the hydrogen bond network from the sugar group. An additional low-frequency mechanism (Process II) with a large dielectric strength was observed due to the internal dynamics of the self-assembly organization. Phase sensitive domain heterogeneity in the bicontinuous cubic phase was related to the diffusion of charge carriers. The microscopic features of charge hopping were modelled using the random walk scheme, and two charge carrier hopping lengths were estimated for two glycolipid systems. For Process I, the hopping length is comparable to the hydrogen bond and is related to the dynamics of the hydrogen bond network. Additionally, that for Process II is comparable to the bilayer spacing, hence confirming that this low-frequency mechanism is associated with the internal dynamics within the phase.

  9. Experimental investigation of phase equilibria in the Co-W-V ternary system

    International Nuclear Information System (INIS)

    Liu Xingjun; Zhu Yihong; Yu Yan; Wang Cuiping

    2011-01-01

    Highlights: → Three isothermal sections of the Co-W-V ternary system at 1100 deg. C, 1200 deg. C and 1300 deg. C were determined. → No ternary compound was found in the Co-W-V ternary system. → A stable liquid miscibility gap is newly discovered in the Co-W-V ternary system. → This work is of great essence to establish the thermodynamic database for the Co-based alloys. - Abstract: The phase equilibria in the Co-W-V ternary system were experimentally investigated by optical microscopy (OM), electron probe microanalysis (EPMA) and X-ray diffraction (XRD) on the equilibrated alloys. Three isothermal sections of the Co-W-V ternary system at 1100 deg. C, 1200 deg. C and 1300 deg. C were determined, and no ternary compound was found in this system. In addition, a novel phenomena induced by the liquid phase separation in the Co-W-V alloys was firstly discovered, suggesting that a stable liquid miscibility gap exists in the Co-W-V ternary system. The newly determined phase equilibria and firstly discovered phase separation phenomena in the Co-W-V system will provide important information for the development of Co-W based alloys.

  10. Investigation of phase-change coatings for variable thermal control of spacecraft

    Science.gov (United States)

    Kelliher, W. C.; Young, P. R.

    1972-01-01

    An investigation was conducted to determine the feasibility of producing a spacecraft coating system that could vary the ratio of its solar absorptance to thermal emittance to adjust automatically for changes in the thermal balance of a spacecraft. This study resulted in a new concept called the phase-change effect which uses the change that occurs in the optical properties of many materials during the phase transition from a crystalline solid to an amorphous material. A series of two-component model coatings was developed which, when placed on a highly reflecting substrate, exhibited a sharp decrease in solar absorptance within a narrow temperature range. A variable thermal control coating can have a significant amount of temperature regulation with the phase-change effect. Data are presented on several crystallite-polymer formulations, their physical and optical properties, and associated phase-change temperatures. Aspects pertaining to their use in a space environment and an example of the degree of thermal regulation attainable with these coatings is also given.

  11. International Before Commercial: Investigating the Pre-Commercial Phase of International New Ventures

    Directory of Open Access Journals (Sweden)

    Nicolai Løvdal

    2013-03-01

    Full Text Available In this study we focus newly established companies within the wave and tidal energy industry. Companies in this industry have not yet reached the phase of commercial production and sales. Our study investigates presents three case companies, analyzing their development pattern and how they access resources through international activities in the pre-commercial phase. The results reveal extensive international activities, were the companies seek for and exploits resources from a variety of countries even the early phases of their development. In fact, they are willing to establish large part of their activities in foreign countries (and even move their home base to access resources. A key implication for managers is the need of balancing international use of resources and international access to resources. From the perspective of policy makers, the case study illustrate how countries and regions compete in order to attract the attention from and activity of firms in an emerging industry. These companies relocate activity across borders depending on the support framework offered. For researchers, the study demonstrates the need of focus on the international dimension of firm activity as early as in the pre-commercial phase.

  12. Investigations on the transverse phase space at a photo injector for minimized emittance

    International Nuclear Information System (INIS)

    Miltchev, V.

    2006-08-01

    Radio frequency photoinjectors are electron sources able to generate beams of extremely high brightness, which are applicable to linac driven Free Electron Lasers (FEL). Because of the high phase space density, the dynamics of the electron beam is dominated by space charge interactions between the particles. This thesis studies the transverse phase space of space charge dominated electron beams produced by the Photo Injector Test Facility in Zeuthen (PITZ). The operation conditions for minimizing the transverse emittance are studied experimentally, theoretically and in simulations. The influence of the longitudinal profile of the driving UV laser pulse on the transverse emittance is investigated. Emphasis is placed on the experimental study of the emittance as a function of different machine parameters like the laser beam spot size, the amplitude of the focusing magnetic field, the rf phase and the electron bunch charge. First investigations on the thermal emittance for Cs 2 Te photocathodes under rf operating conditions are presented. Measurements of the thermal emittance scaling with the photocathode laser spot size are analyzed. The significance of the applied rf field in the emittance formation process is discussed. (orig.)

  13. Investigations on the transverse phase space at a photo injector for minimized emittance

    Energy Technology Data Exchange (ETDEWEB)

    Miltchev, V.

    2006-08-15

    Radio frequency photoinjectors are electron sources able to generate beams of extremely high brightness, which are applicable to linac driven Free Electron Lasers (FEL). Because of the high phase space density, the dynamics of the electron beam is dominated by space charge interactions between the particles. This thesis studies the transverse phase space of space charge dominated electron beams produced by the Photo Injector Test Facility in Zeuthen (PITZ). The operation conditions for minimizing the transverse emittance are studied experimentally, theoretically and in simulations. The influence of the longitudinal profile of the driving UV laser pulse on the transverse emittance is investigated. Emphasis is placed on the experimental study of the emittance as a function of different machine parameters like the laser beam spot size, the amplitude of the focusing magnetic field, the rf phase and the electron bunch charge. First investigations on the thermal emittance for Cs{sub 2}Te photocathodes under rf operating conditions are presented. Measurements of the thermal emittance scaling with the photocathode laser spot size are analyzed. The significance of the applied rf field in the emittance formation process is discussed. (orig.)

  14. Theoretical investigation of the long-lived metastable AlO2+ dication in gas phase

    International Nuclear Information System (INIS)

    Sghaier, Onsi; Abdallah, Hassan H.; Abdullah, Hewa Y.; Jaidane, Nejm Eddine; Al Mogren, Muneerah Mogren; Hochlaf, Majdi

    2016-01-01

    Highlights: • Theoretical investigation of gas-phase molecular species AlO 2+ . • Spectroscopic parameters of this dication in its electronic ground and exited states. • Theoretical double ionization spectrum of AlO. - Abstract: We report the results of a detailed theoretical study of the electronic ground and excited states of the gas-phase doubly charged ion AlO 2+ using high-level ab initio computer calculations. Both standard and explicitly correlated methods were used to calculate their potential energy curves and spectroscopic parameters. These computations show that the ground state of AlO 2+ is X 2 Π. The internuclear equilibrium distance of AlO 2+ (X 2 Π) is computed 1.725 Å. We also deduced the adiabatic double ionization and charge stripping energies of AlO to be about 27.45 eV and 17.80 eV, respectively.

  15. Experimental investigation and thermodynamic prediction of the Bi-Sb-Zn phase diagram

    Energy Technology Data Exchange (ETDEWEB)

    Minic, Dusko, E-mail: dminic65@nadlanu.com [University of Pristina, Faculty of Technical Sciences, 38220 Kosovska Mitrovica (Serbia); Dokic, Jelena [University of Pristina, Faculty of Technical Sciences, 38220 Kosovska Mitrovica (Serbia); Cosovic, Vladan; Stajic-Trosic, Jasna [Institute of Chemistry, Tehnology and Metallurgy, Njegoseva 12, 11000 Belgrade (Serbia); Zivkovic, Dragana [University of Belgrade, Technical Faculty, VJ 12, 19210 Bor (Serbia); Dervisevic, Irma [University of Pristina, Faculty of Technical Sciences, 38220 Kosovska Mitrovica (Serbia)

    2010-07-01

    Phase diagram of the ternary Bi-Sb-Zn system was investigated experimentally by DTA and SEM-EDS methods and analytically by CALPHAD method. The liquidus projection, invariant equilibria, several vertical sections and isothermal section at 300 {sup o}C were predicted using COST 531 thermodynamic database. Phase transition temperatures of alloys along three predicted vertical sections of the Bi-Sb-Zn ternary system with molar ratio Bi:Sb = 1, Bi:Zn = 1 and Sb:Zn = 1, were measured by differential thermal analysis (DTA). Predicted isothermal section at 300 {sup o}C was compared with the results of the scanning electron microscope (SEM) with energy dispersive spectrometry (EDS) analysis from this work.

  16. Investigations on the growth kinetics of Laves phase precipitates in 12% Cr creep-resistant steels: Experimental and DICTRA calculations

    International Nuclear Information System (INIS)

    Prat, O.; Garcia, J.; Rojas, D.; Carrasco, C.; Inden, G.

    2010-01-01

    The growth kinetics of Laves phase precipitates (type Fe 2 W) in the early stage of creep (650 deg. C for 10,000 h) in two 12% Cr ferrite-martensitic steels has been investigated. In one alloy the Laves phase formed on tempering, while in the second alloy the Laves phase precipitated during creep. Kinetic simulations were performed using the software DICTRA. The particle size of the Laves phase was measured on transmission electron microscopy samples. The equilibrium phase fraction of the Laves phase was reached in the first thousand hours. Simulations of particle growth showed good agreement with the experimental results. Competitive growth between M 23 C 6 and the Laves phase showed that M 23 C 6 carbides reached their equilibrium after 12 days, whereas the Laves phase reached equilibrium after 3 months. Simulations of the influence of the interfacial energy and addition of Co, Cu and Si on Laves phase precipitation are presented.

  17. An investigation of phase transitions in solid methane and deuterated derivatives to pressures of 3 kbar

    International Nuclear Information System (INIS)

    Sprik, M.

    1982-01-01

    The first part of this thesis is an experimental investigation of the interaction responsible for the I-II transition and the second part comprises three theoretical studies of several of the properties of phase I and II. The first chapter of part I, is a general introduction to a thermodynamic treatment of the isotope effect in an orientational phase transition. The thermodynamic approach yields a corresponding state model for the phase diagrams of the five isotopes of methane (CH 4 , CHD 3 , CH 2 D 2 , CH 3 D and CD 4 ). In the remaining two chapters of part I, the corresponding state relation mentioned above is applied to the I-II transition of methane in order to obtain an experimental value for the effective exponent n of the dependence on intermolecular separation of the ordering anisotropic interaction. Part II starts with a derivation of a quasi-classical approximation to the statistical density matrix of a free spherical top. While the orientational system is treated classically, the consequences of the other characteristic of the methane molecules are considered, i.e. the high approximately odd symmetry of the molecule (the octupole field in phase II is odd under spatial inversion). It is argued that the renormalization group analysis of critical phenomena in certain highly complicated antiferromagnetic systems may be equally well applied to the I-II transition in methane. Finally, the study of the quantum effect in phase II is resumed. The spin lattice relaxation time at very low temperature is calculated from first principles using an orientational dynamical process of purely quantum-mechanical nature. (Auth.)

  18. Contaminated Materials and Groundwater Investigation Work Plan, Chaska Flood Control Project Stages 3 and 4, Chaska, Minnesota: MPCA Phase II Investigation Work Plan

    National Research Council Canada - National Science Library

    1992-01-01

    This Phase II Investigation Work Plan discusses the field work and laboratory testing required to determine the extent of contaminated materials to be encountered during the construction of Stage 4...

  19. Numerical investigation of the early flight phase in ski-jumping.

    Science.gov (United States)

    Gardan, N; Schneider, A; Polidori, G; Trenchard, H; Seigneur, J M; Beaumont, F; Fourchet, F; Taiar, R

    2017-07-05

    The purpose of this study is to develop a numerical methodology based on real data from wind tunnel experiments to investigate the effect of the ski jumper's posture and speed on aerodynamic forces in a wide range of angles of attack. To improve our knowledge of the aerodynamic behavior of the ski jumper and his equipment during the early flight phase of the ski jump, we applied CFD methodology to evaluate the influence of angle of attack (α=14°, 21.5°, 29°, 36.5° and 44°) and speed (u=23, 26 and 29m/s) on aerodynamic forces in the situation of stable attitude of the ski jumper's body and skis. The standard k-ω turbulence model was used to investigate both the influence of the ski jumper's posture and speed on aerodynamic performance during the early flight phase. Numerical results show that the ski jumper's speed has very little impact on the lift and drag coefficients. Conversely, the lift and drag forces acting on the ski jumper's body during the early flight phase of the jump are strongly influenced by the variations of the angle of attack. The present results suggest that the greater the ski jumper's angle of inclination, with respect to the relative flow, the greater the pressure difference between the lower and upper parts of the skier. Further studies will focus on the dependency of the parameters with both the angle of attack α and the body-ski angle β as control variables. It will be possible to test and optimize different ski jumping styles in different ski jumping hills and investigate different environmental conditions such as temperature, altitude or crosswinds. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Investigation of the phase structure of a chirally-invariant Higgs-Yukawa model

    CERN Document Server

    Bulava, John; Hou, George W.-S.; Jansen, Karl; Knippschild, Bastian; Lin, C.-J.David; Nagai, Kei-Ichi; Nagy, Attila; Ogawa, Kenji

    2012-01-01

    We present new data on our ongoing project on the investigation of the phase structure of the Higgs-Yukawa model at large bare Yukawa couplings. The data presented last year are extended in terms of statistics, the number of bare Yukawa couplings at existing, and new larger volumes. In addition, this study is extended by a finite temperature project at the physical top quark mass m_t =175 GeV and a hypothetical fourth generation top quark with a mass of m_t' =700 GeV .

  1. High-pressure fluid-phase equilibria: Experimental methods and systems investigated (2000-2004)

    DEFF Research Database (Denmark)

    Dohrn, Ralf; Peper, Stephanie; Fonseca, José

    2010-01-01

    , and the experimental method used for the measurements are given in 54 tables. Most of experimental data in the literature have been given for binary systems. Of the 1204 binary systems, 681 (57%) have carbon dioxide as one of the components. Information on 156 pure components, 451 ternary systems of which 267 (62......%) contain carbon dioxide, 150 multicomponent and complex systems, and 129 systems with hydrates is given. Experimental methods for the investigation of high-pressure phase equilibria are classified and described. Work on the continuation of the review series is under way, covering the period between 2005...

  2. QUEOS, an experimental investigation of the premixing phase with hot spheres

    Energy Technology Data Exchange (ETDEWEB)

    Meyer, L. [Forschungszentrum Karlsruhe GmbH Technik und Umwelt (Germany). Inst. fuer Neutronenphysik und Reaktortechnik

    1998-01-01

    A second series of experiments with hot spheres to investigate the premixing phase of a steam explosion has been performed in the QUEOS facility at FZK. The diameter of the sphere jet plunging into the water has been reduced from 180 mm to 100 mm and larger masses have been employed. Both changes led to longer pours, compared to the short pours in the first series. The data of seven experiments are presented using three types of spheres at 1800 K and total volumes of approximately two and four liters, respectively. High speed films were taken, pressures, water temperatures and the steaming rate were measured. (author)

  3. Investigating mixed phase clouds using a synergy of ground based remote sensing measurements

    Science.gov (United States)

    Gierens, Rosa; Kneifel, Stefan; Löhnert, Ulrich

    2017-04-01

    obtained from a Doppler wind lidar. Furthermore, the Cloudnet scheme (www.cloud-net.org), that combines radar, lidar and microwave radiometer observations with a forecast model to provide a best estimate of cloud properties, is used for identifying mixed phase clouds. The continuous measurements carried out at AWIPEV make it possible to characterize the macro- and micro- physical properties of mixed-phase clouds on a long-term, statistical basis. The Arctic observations are compared to a 5-year observational data set from Jülich Observatory for Cloud Evolution (JOYCE) in Western Germany. The occurrence of different types of clouds (with focus on mixed-phase and super-cooled clouds), the distribution of ice and liquid within the clouds, the turbulent environment as well as the temperatures where the different phases are occurring are investigated.

  4. A Preliminary Experimental Investigation of Wet Fine Erosion in Two-Phase Flow

    Science.gov (United States)

    Ya, H. H.; luthfi, Haziq; ngo, Nguyet-tran; Hassan, Suhaimi; pao, William

    2018-03-01

    Solid particles below 62 μm is classified as fine. In oil producing operation, the most commonly used downhole sand screen can only capture solid particles of 140 μm and above. Most predictive erosion model is limited to particle size of 100 μm with single phase flow assumption because it is commonly believed that erosion due to particles below 100 μm is insignificant and typically ignored by oil and gas consultants when proposing facilities design. The objective of this paper is to investigate the impact of fines particle on mild steel plate in two-phase flow at different collision angles. A two phase flow loop was set up. The average size of fine particle was 60 μm, mixed with water with sand to water ratio at 1:65 wt/wt. The mild steel plates were oriented at three different impact angles which are -30°, 30° and 90°, with respect to the horizon. Scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), surface roughness and Vickers micro hardness techniques were used to quantify the effects of fine particle on the exposed surface.

  5. Experimental investigation of phase equilibria in the Zr-Cu-Ni ternary system

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Mujin; Wang, Cuiping; Yang, Shuiyuan; Shi, Zhan; Han, Jiajia; Liu, Xingjun [Xiamen Univ. (China). College of Materials and Fujian Provincial Key Lab. of Materials Genome

    2017-08-15

    The phase equilibria in the Zr-Cu-Ni ternary system are investigated combined with X-ray diffraction, electron probe micro-analysis and differential scanning calorimetry. Two isothermal sections of the Zr-Cu-Ni ternary system at 1 000 C and 1 100 C are experimentally established. Most of the binary intermetallic compounds, e.g. Zr{sub 7}Ni{sub 10}, ZrNi, ZrNi{sub 5}, Zr{sub 14}Cu{sub 51}, and Zr{sub 2}Cu{sub 9}, show a remarkable ternary solubility. A new ternary compound named τ{sub 3} (Zr{sub 31.1-30.7} . Cu{sub 28.5-40.3}Ni{sub 40.4-29.0}) is detected at 1 000 C and dissolved at 1 020 C because the nearby large liquid phase field further expands. The newly determined phase equilibria will provide important information for both thermodynamic assessment and alloy design of Zr-based metallic glass.

  6. Numerical investigation of refrigeration machine compressor operation considering single-phase electric motor dynamic characteristics

    Science.gov (United States)

    Baidak, Y.; Smyk, V.

    2017-08-01

    Using as the base the differential equations system which was presented in relative units for generalized electric motor of hermetic refrigeration compressor, mathematical model of the software for dynamic performance calculation of refrigeration machine compressors drive low-power asynchronous motors was developed. Performed on its ground calculations of the basic model of two-phase electric motor drive of hermetic compressor and the proposed newly developed model of the motor with single-phase stator winding, which is an alternative to the industrial motor winding, have confirmed the benefits of the motor with innovative stator winding over the base engine. Given calculations of the dynamic characteristics of compressor drive motor have permitted to determine the value of electromagnetic torque swinging for coordinating compressor and motor mechanical characteristics, and for taking them into consideration in choosing compressor elements construction materials. Developed and used in the process of investigation of refrigeration compressor drive asynchronous single-phase motor mathematical and software can be considered as an element of computer-aided design system for design of the aggregate of refrigeration compression unit refrigerating machine.

  7. Investigation of the Hydrogen Silsesquioxane (HSQ) Electron Resist as Insulating Material in Phase Change Memory Devices

    Science.gov (United States)

    Zhou, Jiao; Ji, Hongkai; Lan, Tian; Yan, Junbing; Zhou, Wenli; Miao, Xiangshui

    2015-01-01

    Phase change random access memory (PCRAM) affords many advantages over conventional solid-state memories due to its nonvolatility, high speed, and scalability. However, high programming current to amorphize the crystalline phase through the melt-quench process of PCRAM, known as the RESET current, poses a critical challenge and has become the most significant obstacle for its widespread commercialization. In this work, an excellent negative tone resist for high resolution electron beam lithography, hydrogen silsesquioxane (HSQ), has been investigated as the insulating material which locally blocks the contact between the bottom electrode and the phase change material in PCRAM devices. Fabrications of the highly scaled HSQ nanopore arrays (as small as 16 nm) are presented. The insulating properties of the HSQ material are studied, especially under e-beam exposure plus thermal curing. Some other critical issues about the thickness adjustment of HSQ films and the influence of the PCRAM electrode on electron scattering in e-beam lithography are discussed. In addition, the HSQ material was successfully integrated into the PCRAM devices, achieving ultra-low RESET current (sub-100 μA), outstanding on/off ratios (~50), and improved endurance at tens of nanometers.

  8. Vibrational spectroscopic and dielectric properties investigations of phase transitions in KMgPO4 compound

    Science.gov (United States)

    Miladi, L.; Oueslati, A.; Guidara, K.

    2017-11-01

    The potassium orthophosphate KMgPO4 with a β-tridymite structure was synthesized via solid-state reaction. X-ray diffraction study confirms the formation of a single phase material which crystallizes at room temperature in monoclinic system. This compound has been investigated by vibrational spectroscopy in the temperature range573-723 K. Thermal analysis shows that this composition undergoes two phase transitions at T1=633Kand T2=693 K.The evolution of Raman line ν and half -width Δν versus temperature introduces huge changes which are associated with the phase transitions originating from the reorientation of the PO4 tetrahedron. Besides, an analysis of the dielectric constants ε‧ and ε″versus temperature at several frequencies shows a distribution of relaxation times. This relaxation is probably due to the change in dynamical state of the K+ cation. The ac conductivity behavior can be understood in terms of the motions of K+ cations along the tunnels which are formed by six-membered rings of MgO4 and PO4 tetrahedron linked by common vertices. The activation energies values obtained from the thermal evolution of the conductivity are: Ea1=0.52 eV (T693 K).

  9. Investigation of two-phase liquid-metal magnetohydrodynamic power systems

    International Nuclear Information System (INIS)

    Amend, W.E.; Fabris, G.; Cutting, J.

    1975-01-01

    A two-phase Liquid-Metal MHD (LMMHD) system is under development at the Argonne National Laboratory, and results are presented for detailed cycle analysis and systems studies, the experimental facility, and the thermal and magneto fluid mechanics problems encountered. The studies indicate that the LMMHD cycle will operate efficiently in the temperature range of 1000-1600 0 F (50 percent efficiency with a maximum cycle temperature of 1600 0 F) and is therefore potentially compatible with many advanced heat sources under development such as the LMFBR, fluidized-bed coal combustor, HTGCR and the fusion reactor. Of special interest is the coupling to the LMFBR thereby eliminating the costly, potentially hazardous liquid-metal/water interface. The results of detailed parametric studies of the heat transfer interfaces between an LMMHD power cycle and an LMFBR and a steam bottoming plant are described. Experimental evaluation of the two-phase LMMHD generator was performed in an ambient temperature NaK--N 2 facility at ANL. Results of these experiments, performed to determine the operating characteristics of the device as a function of the various independent parameters and to investigate two-phase flow, are given. (U.S.)

  10. Horonobe Underground Research Laboratory project. Plans of investigations during shaft and drift excavation (Construction of underground facilities: Phase II)

    International Nuclear Information System (INIS)

    2005-06-01

    Horonobe Underground Research Laboratory Project is planned for over 20 years to establish the scientific and technical basis for the underground disposal of high-level radioactive wastes in Japan. The investigations are conducted by JNC in three phases, from the surface (Phase I), during the construction of the underground facilities (Phase II), and using the facilities (Phase III). This report concerns the investigation plans for Phase II. During excavation of shafts and drifts, detailed geological and borehole investigation will be conducted and the geological model constructed in Phase I is evaluated and revised by newly acquired data of geophysical and geological environment. Detailed in-situ experiments, as well as the effects of shaft excavation, are also done to study long-term changes, rock properties, groundwater flow and chemistry to ensure the reliability of repository technology and establish safety assessment methodology. (S. Ohno)

  11. Local probe investigations of the electronic phase diagrams of iron pnictides and chalcogenides

    Energy Technology Data Exchange (ETDEWEB)

    Materne, Philipp

    2015-09-24

    In this work, the electronic phase diagrams of Ca{sub 1-x}Na{sub x}Fe{sub 2}As{sub 2} and Fe{sub 1+y}Te were investigated using muon spin relaxation and Moessbauer spectroscopy. Single crystals of Ca{sub 1-x}Na{sub x}Fe{sub 2}As{sub 2} with x = 0.00, 0.35, 0.50, and 0.67 were examined. The undoped 122 parent compound CaFe{sub 2}As{sub 2} is a semi metal and shows antiferromagnetic commensurate spin density wave order below 167 K. By hole doping via Na substitution, the magnetic order is suppressed and superconductivity emerges including a Na-substitution level region, where both phases coexist. Upon Na substitution, a tilting of the magnetic moments out of the ab-plane is found. The interaction of the magnetic and superconducting order parameter in this coexistence region was studied and a nanoscopic coexistence of both order parameters is found. This is proven by a reduction of the magnetic order parameter of 7 % in x = 0.50 below the superconducting transition temperature. This reduction was analysed using Landau theory and a systematic correlation between the reduction of the magnetic order parameter and the ratio of the transition temperatures, T{sub c}/T{sub N}, for the 122 family of the iron pnictides is presented. The magnetic phase transition is accompanied by a tetragonal-to-orthorhombic phase transition. The lattice dynamics at temperatures above and below this magneto-structural phase transition were studied and no change in the lattice dynamics were found. However, the lattice for finite x is softer than for the undoped compound. For x = 0.67, diluted magnetic order is found. Therefore, the magnetism in Ca{sub 1-x}Na{sub x}Fe{sub 2}As{sub 2} is persistent even at optimal doping. The superconducting state is investigated by measuring the temperature dependence of the magnetic penetration depth, where two superconducting gaps with a weighting of nearly 50:50 are obtained. A temperature independent anisotropy of the magnetic penetration depth γ{sub

  12. Investigating Phase Transform Behavior in Indium Selenide Based RAM and Its Validation as a Memory Element

    Directory of Open Access Journals (Sweden)

    Swapnil Sourav

    2016-01-01

    Full Text Available Phase transform properties of Indium Selenide (In2Se3 based Random Access Memory (RAM have been explored in this paper. Phase change random access memory (PCRAM is an attractive solid-state nonvolatile memory that possesses potential to meet various current technology demands of memory design. Already reported PCRAM models are mainly based upon Germanium-Antimony-Tellurium (Ge2Sb2Te5 or GST materials as their prime constituents. However, PCRAM using GST material lacks some important memory attributes required for memory elements such as larger resistance margin between the highly resistive amorphous and highly conductive crystalline states in phase change materials. This paper investigates various electrical and compositional properties of the Indium Selenide (In2Se3 material and also draws comparison with its counterpart mainly focusing on phase transform properties. To achieve this goal, a SPICE model of In2Se3 based PCRAM model has been reported in this work. The reported model has been also validated to act as a memory cell by associating it with a read/write circuit proposed in this work. Simulation results demonstrate impressive retentivity and low power consumption by requiring a set pulse of 208 μA for a duration of 100 μs to set the PCRAM in crystalline state. Similarly, a reset pulse of 11.7 μA for a duration of 20 ns can set the PCRAM in amorphous state. Modeling of In2Se3 based PCRAM has been done in Verilog-A and simulation results have been extensively verified using SPICE simulator.

  13. Electron microscopic investigations of the as-synthesised and dissociated Y:124 HTSC phases

    International Nuclear Information System (INIS)

    Srivastava, A.K.; Ramakrishna, K.; Srivastava, O.N.

    1992-01-01

    The Y:124 was synthesised at ambient oxygen pressure using an oxygen enhancer (NaNO 3 ). The as-synthesised material was thermally dissociated at 915degC for various time spans, e.g., 1, 2 and 5 min. X-ray diffraction (XRD) results showed that the undissociated sample corresponds to the Y:124 phase, whereas the dissociated samples consisted of mixed phases. For the samples dissociated for 1 min these were Y:124 and Y:123 (with some traces of CuO), for dissociation times of 2 and 5 min these were dominantly Y:123 and CuO. From R-T and L-T (inductance-temperature) measurements, it was found that the undissociated Y:124 possesses a Tc(R=0)∝80 K and there is no drop in inductance for dissociated samples (2 and 5 min). Microstructural investigations of Y:124 revealed that the material dissociated for 1 min is biphasic, consisting of Y:124 and Y:123. Besides stacking disorder, local area superstructures along ''c'' emanating from the native Y:124 phase were also observed. This is thought to ensue from the random and sequential removal of Cu-O chains from the Y:124 structure. The sample subjected to longer dissociation times, i.e., 2 and 5 min consists of Y:123 and CuO precipitates. For longer dissociation times, e.g., 2 min and above, the Y:124 phase nearly completely converts into Y:123 and CuO. (orig.)

  14. Investigation of gas-phase decontamination of internally radioactively contaminated gaseous diffusion process equipment and piping

    International Nuclear Information System (INIS)

    Bundy, R.D.; Munday, E.B.

    1991-01-01

    Construction of the gaseous diffusion plants (GDPs) was begun during World War 2 to produce enriched uranium for defense purposes. These plants, which utilized UF 6 gas, were used primarily for this purpose through 1964. From 1959 through 1968, production shifted primarily to uranium enrichment to supply the nuclear power industry. Additional UF 6 -handling facilities were built in feed and fuel-processing plants associated with the uranium enrichment process. Two of the five process buildings at Oak ridge were shut down in 1964. Uranium enrichment activities at Oak Ridge were discontinued altogether in 1985. In 1987, the Department of Energy (DOE) decided to proceed with a permanent shutdown of the Oak Ridge Gaseous Diffusion Plant (ORGDP). DOE intends to begin decommissioning and decontamination (D ampersand D) of ORGDP early in the next century. The remaining two GDPs are expected to be shut down during the next 10 to 40 years and will also require D ampersand D, as will the other UF 6 -handling facilities. This paper presents an investigation of gas- phase decontamination of internally radioactively contaminated gaseous diffusion process equipment and piping using powerful fluorinating reagents that convert nonvolatile uranium compounds to volatile UF 6 . These reagents include ClF 3 , F 2 , and other compounds. The scope of D ampersand D at the GDPs, previous work of gas-phase decontamination, four concepts for using gas-phase decontamination, plans for further study of gas-phase decontamination, and the current status of this work are discussed. 13 refs., 15 figs

  15. A Heat Transfer Investigation of Liquid and Two-Phase Methane

    Science.gov (United States)

    VanNoord, Jonathan

    2010-01-01

    A heat transfer investigation was conducted for liquid and two-phase methane. The tests were conducted at the NASA Glenn Research Center Heated Tube Facility (HTF) using resistively heated tube sections to simulate conditions encountered in regeneratively cooled rocket engines. This testing is part of NASA s Propulsion and Cryogenics Advanced Development (PCAD) project. Nontoxic propellants, such as liquid oxygen/liquid methane (LO2/LCH4), offer potential benefits in both performance and safety over equivalently sized hypergolic propulsion systems in spacecraft applications. Regeneratively cooled thrust chambers are one solution for high performance, robust LO2/LCH4 engines, but cooling data on methane is limited. Several test runs were conducted using three different diameter Inconel 600 tubes, with nominal inner diameters of 0.0225-, 0.054-, and 0.075-in. The mass flow rate was varied from 0.005 to 0.07 lbm/sec. As the current focus of the PCAD project is on pressure fed engines for LO2/LCH4, the average test section outlet pressures were targeted to be 200 psia or 500 psia. The heat flux was incrementally increased for each test condition while the test section wall temperatures were monitored. A maximum average heat flux of 6.2 Btu/in.2 sec was achieved and, at times, the temperatures of the test sections reached in excess of 1800 R. The primary objective of the tests was to produce heat transfer correlations for methane in the liquid and two-phase regime. For two-phase flow testing, the critical heat flux values were determined where the fluid transitions from nucleate boiling to film boiling. A secondary goal of the testing was to measure system pressure drops in the two-phase regime.

  16. Phase transition of iron sulphide minerals under hydrothermal conditions and magnetic investigations

    Science.gov (United States)

    Li, Ssu Han; Chen, Yen-Hua; Lee, Jey-Jau; Sheu, Hwo-Shuenn

    2018-01-01

    Iron sulphide minerals have been used in industrial applications for many years, and more recently there has been increasing interest in the use of iron sulphide nanomaterials because of their useful properties and low cost. Previous studies have mainly focused on the synthesis of iron sulphides, but their phase transition and micro-magnetic properties are still unclear. In this study, iron sulphide minerals were synthesized via a hydrothermal method, and their phase transition mechanisms and magnetic properties were investigated. Ex situ and in situ X-ray diffraction results of the iron-sulphur system under hydrothermal conditions suggested that the transformation sequence followed the order of mackinawite (FeS) → greigite (Fe3S4) → smythite (Fe9S11) → pyrrhotite (Fe9S10). Pure greigite and pyrrhotite were obtained during the synthesis processes, after 1 h at 120 and 160 °C, respectively. Greigite showed a granular morphology with particle diameters around 30 nm, and pyrrhotite comprised stacked hexagonal sheets with thousands of nanometers in width. Pyrrhotite showed anti-ferromagnetic behaviour; however, it did not saturate up to magnetic field of 7 T. Greigite was ferrimagnetic, with a high saturation magnetization of 62.7 Am2 kg-1 and coercive magnetic field of 27.6 mT. Magnetic force microscope measurements of greigite revealed that its magnetic structure belonged to a spin-canted single domain. Overall, this study provides new information on the phase transition mechanism, related reaction formulas, and magnetic properties of iron sulphides, and it emphasizes the important role played by temperature/time in phase transitions.

  17. Investigation of a cylindrical chemosorptive denuder for sampling and phase separation of toluene diisocyanate aerosols.

    Science.gov (United States)

    Nordqvist, Yvonne; Nilsson, Ulrika; Colmsjö, Anders

    2005-07-01

    A cylindrical chemosorptive denuder in series with a glass fibre filter has been evaluated for sampling toluene diisocyanate (TDI) aerosols. The sampler is designed for measuring personal exposure to diisocyanates. Several denuder coatings and derivatising reagents were investigated. Dimethylpolysiloxane (SE-30) and 5% phenyl dimethylpolysiloxane (SE-54) with either dibutylamine (DBA) or dipentylamine (DPeA) as derivatising reagents yielded the lowest vapour breakthrough (the amount (%) of the vapour that passes through the denuder), close to values predicted by theory. Immobilisation of the SE-30 denuder coating by in-situ cross-linking yielded comparable results. With an SE-30/DBA-coated denuder operating within an airflow range of 100-500 mL min(-1), the phase separation was shown to be consistent with theoretical predictions derived by use of the Gormley-Kennedy equation. This provides a means of calculating the vapour breakthrough and correcting experimentally obtained values with regard to vapour-particulate phase distribution, suggesting that the denuder can provide accurate phase-distribution measurements. The SE-30/DBA denuder can be used over a concentration range spanning nearly six orders of magnitude. Its capacity is sufficient to perform 15-min exposure measurements of a TDI aerosol with air concentrations as high as 1,700 microg m(-3), 40 times higher than the Swedish occupational exposure limit (OEL). At the other end of the range, the estimated limit of detection (LOD) was less than 2 ng m(-3) for both the vapour and the aerosol phases when LC-ESI-MS-MS was used for chemical analysis.

  18. Structural investigations on the tetragonal to cubic phase transformations in zirconia induced by progressive yttrium additions

    Science.gov (United States)

    Vasanthavel, S.; Kannan, S.

    2018-01-01

    Yttria stabilized zirconia (YSZ) is inevitable in many industrial applications. Yttrium additions in ZrO2 system induces either tetragonal (t-ZrO2) or cubic (c-ZrO2) phase stabilization that predominantly depends on the yttrium content. Here, the structural changes in ZrO2 system upon a wide range of yttrium additions are investigated. Powder synthesis is carried out through citrate-nitrate assisted sol-gel technique and analytical techniques involving XRD, Raman spectra and structural analysis through Rietveld refinement were utilized to investigate the structural changes in ZrO2 upon progressive yttrium additions. The critical limit of yttrium content to retain unique t-ZrO2, mixtures of t-ZrO2 and c-ZrO2 and discrete c-ZrO2 is determined.

  19. INVESTIGATION OF THE FACTORS AFFECT PHASE INDUCTANCE IN SWITCHED RELUCTANCE MOTORS

    Directory of Open Access Journals (Sweden)

    Ahmet FENERCİOĞLU

    2007-02-01

    Full Text Available In this study, the factors affecting change of the phase inductance in a switched reluctance motor (SRM have been investigated. The motor inductance is a function of both excitation current and rotor position and it depends on motor geometry, relative permeability, saturation and fringing and end-turn field. Non-linearity of SRM leads to difficulties for the development of analytical methods for predicting the flux linkages, co–energy change and inductance at all rotor positions these effects in the 6/4 SRM obtained from analytical way and predicted by 3D finite element method (Ansoft RMxprt, Ansoft Maxwell 3D have been investigated. Results of simulations and analytical solutions have been relatively compared.

  20. Final Phase II report : QuickSite(R) investigation, Everest, Kansas.

    Energy Technology Data Exchange (ETDEWEB)

    LaFreniere, L. M. (Environmental Research)

    2003-11-01

    this reason, the CCC/USDA is conducting an environmental site investigation to determine the source(s) and extent of the carbon tetrachloride contamination at Everest and to assess whether the contamination requires remedial action. The investigation at Everest is being performed by the Environmental Research Division of Argonne National Laboratory. Argonne is a nonprofit, multidisciplinary research center operated by the University of Chicago for the U.S. Department of Energy (DOE). The CCC/USDA has entered into an interagency agreement with DOE, under which Argonne provides technical assistance to the CCC/USDA with environmental site characterization and remediation at its former grain storage facilities. At these facilities, Argonne is applying its QuickSite{reg_sign} environmental site characterization methodology. This methodology has been applied successfully at a number of former CCC/USDA facilities in Kansas and Nebraska and has been adopted by the American Society for Testing and Materials (ASTM 1998) as standard practice for environmental site characterization. Phase I of the QuickSite{reg_sign} investigation examined the key geologic, hydrogeologic, and hydrogeochemical relationships that define potential contaminant migration pathways at Everest (Argonne 2001). Phase II of the QuickSite{reg_sign} investigation at Everest was undertaken with the primary goal of delineating and improving understanding of the distribution of carbon tetrachloride contamination in groundwater at this site and the potential source area(s) that might have contributed to this contamination. To address this goal, four specific technical objectives were developed to guide the Phase II field studies. Sampling of near-surface soils at the former Everest CCC/USDA facility that was originally planned for Phase I had to be postponed until October 2000 because of access restrictions. Viable vegetation was not available for sampling then. This period is termed the first session of Phase II

  1. Integrated account of method, site selection and programme prior to the site investigation phase

    International Nuclear Information System (INIS)

    2000-12-01

    In order to dispose of the spent nuclear fuel in a safe manner, SKB plans to site a deep repository and an encapsulation plant with associated canister fabrication and transportation system. After an integrated evaluation of feasibility studies and other material, SKB will proceed with investigations of the rock and studies regarding establishment of the deep disposal system in the municipality of Oskarshamn or in Northern Uppland. The plans also include further study of the prospects for a deep repository in the municipality of Nykoeping. In the municipality of Oskarshamn, SKB plans further studies of a siting of the deep repository at Simpevarp. There SKB wants to initiate site investigations with test drilling. For the encapsulation plant, SKB wants to continue studying a siting at CLAB. In Northern Uppland, SKB plans to study two siting alternatives for the deep repository. One is Forsmark in the municipality of Oesthammar, where SKB wants to initiate a site investigation with test drilling. The other is Tierp north of Skutskaer, where SKB intends to start test drilling in an area north of Tierp. First, however, a suitable drilling area with possible transport solutions needs to be defined. This alternative requires the participation of the municipalities of both Tierp and Aelvkarleby. A siting of the encapsulation plant in Northern Uppland will also be studied. For the municipality of Nykoeping, SKB plans to conduct a new safety assessment for the Fjaellveden area, based on data from previous investigations as well as additional studies of how a deep repository could be arranged. SKB will thereby gather data from yet another geographic and geological region beyond those that are prioritized. No test drilling is planned in Nykoeping. The goal of the site investigation phase is to obtain all permits needed to build the planned facilities. It will take an estimated 7 - 8 years to assemble the requisite supporting material, carry out consultations, compile siting

  2. Thermoplastic Micromodel Investigation of Two-Phase Flows in a Fractured Porous Medium

    Directory of Open Access Journals (Sweden)

    Shao-Yiu Hsu

    2017-01-01

    Full Text Available In the past few years, micromodels have become a useful tool for visualizing flow phenomena in porous media with pore structures, e.g., the multifluid dynamics in soils or rocks with fractures in natural geomaterials. Micromodels fabricated using glass or silicon substrates incur high material cost; in particular, the microfabrication-facility cost for making a glass or silicon-based micromold is usually high. This may be an obstacle for researchers investigating the two-phase-flow behavior of porous media. A rigid thermoplastic material is a preferable polymer material for microfluidic models because of its high resistance to infiltration and deformation. In this study, cyclic olefin copolymer (COC was selected as the substrate for the micromodel because of its excellent chemical, optical, and mechanical properties. A delicate micromodel with a complex pore geometry that represents a two-dimensional (2D cross-section profile of a fractured rock in a natural oil or groundwater reservoir was developed for two-phase-flow experiments. Using an optical visualization system, we visualized the flow behavior in the micromodel during the processes of imbibition and drainage. The results show that the flow resistance in the main channel (fracture with a large radius was higher than that in the surrounding area with small pore channels when the injection or extraction rates were low. When we increased the flow rates, the extraction efficiency of the water and oil in the mainstream channel (fracture did not increase monotonically because of the complex two-phase-flow dynamics. These findings provide a new mechanism of residual trapping in porous media.

  3. Gas-Phase Thermal Tautomerization of Imidazole-Acetic Acid: Theoretical and Computational Investigations

    Directory of Open Access Journals (Sweden)

    Saadullah G. Aziz

    2015-11-01

    Full Text Available The gas-phase thermal tautomerization reaction between imidazole-4-acetic (I and imidazole-5-acetic (II acids was monitored using the traditional hybrid functional (B3LYP and the long-range corrected functionals (CAM-B3LYP and ωB97XD with 6-311++G** and aug-cc-pvdz basis sets. The roles of the long-range and dispersion corrections on their geometrical parameters, thermodynamic functions, kinetics, dipole moments, Highest Occupied Molecular Orbital–Lowest Unoccupied Molecular Orbital (HOMO–LUMO energy gaps and total hyperpolarizability were investigated. All tested levels of theory predicted the preference of I over II by 0.750–0.877 kcal/mol. The origin of predilection of I is assigned to the H-bonding interaction (nN8→σ*O14–H15. This interaction stabilized I by 15.07 kcal/mol. The gas-phase interconversion between the two tautomers assumed a 1,2-proton shift mechanism, with two transition states (TS, TS1 and TS2, having energy barriers of 47.67–49.92 and 49.55–52.69 kcal/mol, respectively, and an sp3-type intermediate. A water-assisted 1,3-proton shift route brought the barrier height down to less than 20 kcal/mol in gas-phase and less than 12 kcal/mol in solution. The relatively high values of total hyperpolarizability of I compared to II were interpreted and discussed.

  4. An experimental and numerical investigation of phase change electrodes for therapeutic irreversible electroporation.

    Science.gov (United States)

    Arena, Christopher B; Mahajan, Roop L; Nichole Rylander, Marissa; Davalos, Rafael V

    2013-11-01

    Irreversible electroporation (IRE) is a new technology for ablating aberrant tissue that utilizes pulsed electric fields (PEFs) to kill cells by destabilizing their plasma membrane. When treatments are planned correctly, the pulse parameters and location of the electrodes for delivering the pulses are selected to permit destruction of the target tissue without causing thermal damage to the surrounding structures. This allows for the treatment of surgically inoperable masses that are located near major blood vessels and nerves. In select cases of high-dose IRE, where a large ablation volume is desired without increasing the number of electrode insertions, it can become challenging to design a pulse protocol that is inherently nonthermal. To solve this problem we have developed a new electrosurgical device that requires no external equipment or protocol modifications. The design incorporates a phase change material (PCM) into the electrode core that melts during treatment and absorbs heat out of the surrounding tissue. Here, this idea is reduced to practice by testing hollow electrodes filled with gallium on tissue phantoms and monitoring temperature in real time. Additionally, the experimental data generated are used to validate a numerical model of the heat transfer problem, which is then applied to investigate the cooling performance of other classes of PCMs. The results indicate that metallic PCMs, such as gallium, are better suited than organics or salt hydrates for thermal management, because their comparatively higher thermal conductivity aids in heat dissipation. However, the melting point of the metallic PCM must be properly adjusted to ensure that the phase transition is not completed before the end of treatment. When translated clinically, phase change electrodes have the potential to continue to allow IRE to be performed safely near critical structures, even in high-dose cases.

  5. Critical role of bioanalytical strategies in investigation of clinical PK observations, a Phase I case study

    Science.gov (United States)

    Peng, Kun; Xu, Keyang; Liu, Luna; Hendricks, Robert; Delarosa, Reginald; Erickson, Rich; Budha, Nageshwar; Leabman, Maya; Song, An; Kaur, Surinder; Fischer, Saloumeh K

    2014-01-01

    RG7652 is a human immunoglobulin 1 (IgG1) monoclonal antibody (mAb) targeting proprotein convertase subtilisin/kexin type 9 (PCSK9) and is designed for the treatment of hypercholesterolemia. A target-binding enzyme-linked immunosorbent assay (ELISA) was developed to measure RG7652 levels in human serum in a Phase I study. Although target-binding assay formats are generally used to quantify free therapeutic, the actual therapeutic species being measured are affected by assay conditions, such as sample dilution and incubation time, and levels of soluble target in the samples. Therefore, in the presence of high concentrations of circulating target, the choice of reagents and assay conditions can have a significant effect on the observed pharmacokinetic (PK) profiles. Phase I RG7652 PK analysis using the ELISA data resulted in a nonlinear dose normalized exposure. An investigation was conducted to characterize the ELISA to determine whether the assay format and reagents may have contributed to the PK observation. In addition, to confirm the ELISA results, a second orthogonal method, liquid chromatography tandem mass spectrometry (LC-MS/MS) using a signature peptide as surrogate, was developed and implemented. A subset of PK samples, randomly selected from half of the subjects in the 6 single ascending dose (SAD) cohorts in the Phase I clinical study, was analyzed with the LC-MS/MS assay, and the data were found to be comparable to the ELISA data. This paper illustrates the importance of reagent characterization, as well as the benefits of using an orthogonal approach to eliminate bioanalytical contributions when encountering unexpected observations. PMID:25484037

  6. Investigation of phase stability and oxide ion performance in new perovskite-type bismuth vanadate

    International Nuclear Information System (INIS)

    Al-Alas, Ahlam; Beg, Saba; Al-Areqi, Niyazi A.S.

    2012-01-01

    Samples of the BICDVOX system, formulated as Bi 4 Cd x V 2−x O 11−(3x/2)−δ in the Cd substitution range 0 ≤ x ≤ 0.25 were synthesized using the standard solid state reaction.The correlation between phase stability and oxide ion performance were investigated by variable temperature XRPD, DSC and AC impedance spectroscopy. The substitution of V 5+ by Cd 2+ exhibited different phase transitions upon varying composition. For compositions with x ≤ 0.05, two successive transitions; α↔β↔γ are evident, while the β↔γ transition exists in the composition range 0.05 4+ → V 5+ re–oxidation results in increased defect trapping effects in the system at higher temperatures. -- Highlights: ► γ-Stabilized BICDVOX at lower dopant concentrations. ► Good oxide-ion conductivity at lower temperatures. ► High temperature-vanadium reduction with lower dopant concentrations.

  7. Investigation of the effect of different parameters on the phase inversion temperature O/W nanoemulsions

    Directory of Open Access Journals (Sweden)

    D. Kaviani

    2016-01-01

    Full Text Available Objective(s: Nanoemulsions are a kind of emulsions that can be transparent, translucent (size range 50-200 nm or “milky” (up to 500 nm. Nanoemulsions are adequatly effective for transfer of active component through skin which facilitate the entrance of the active component . The transparent nature of the system and lack of the thickener and fluidity are among advantages of nanoemulsion. Materials and Methods: In this study, a nanoemulsion of lemon oil in water was prepared by the phase inversion temperature (PIT emulsification method in which the tween 40 was used as surfactant. The effect of concentration of NaCl in aqueous phase, pH and weight percent of surfactant and aqueous on the PIT and droplet size were investigated. Results: The results showed that with increasing of concentration of NaCl from 0.05 M to 1 M, PIT decrease from 72 to 50. The average droplet sizes, for 0.1, 0.5 and 1 M of NaCl in 25 ºC are 497.3, 308.1 and 189.9 nm, respectively and the polydispersity indexes are 0.348, 0.334 and 0.307, respectively. Conclusion: Considering the characteristics of nanoemulsions such as being transparent, endurance of solution and droplet size can provide suitable reaction environment for polymerization process used in making hygienic and medical materials.

  8. Online analytical investigations on solvent-, temperature- and water vapour-induced phase transformations of citric acid

    Energy Technology Data Exchange (ETDEWEB)

    Helmdach, L.; Ulrich, J. [Martin-Luther-Universitaet Halle-Wittenberg, Zentrum fuer Ingenieurwissenschaft, Verfahrenstechnik/TVT, Halle (Saale) (Germany); Feth, M.P. [Sanofi-Aventis Deutschland GmbH, Chemical and Process Development Frankfurt Chemistry, Frankfurt (Germany)

    2012-09-15

    It was demonstrated exemplarily for the crystallization of citric acid that the usage of an ultrasound device as well as Raman spectroscopy enables the inline measurement and the control of phase transitions. The influence of different solvent compositions (water and ethanol-water) on the crystallization of citric acid was investigated. By increasing the ethanol content the transformation point was shifted towards higher temperatures. In addition, a strong impact on the nucleation point as well as on the crystal habit was detected in ethanol-water mixtures. The results lead to the assumption that a citric acid solvate exists, which is, however, highly unstable upon isolation from mother liquor and converts fast into the known anhydrate or monohydrate forms of citric acid. The presence of such a solvate, however, could not be proven during this study. Furthermore, factors such as temperature and humidity which might influence the phase transition of the solid product were analyzed by Hotstage-Raman Spectroscopy and Water Vapor Sorption Gravimetry-Dispersive Raman Spectroscopy. Both, temperature as well as humidity show a strong influence on the behaviour of CAM. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  9. Phase II drugs currently being investigated for the treatment of hypogonadism.

    Science.gov (United States)

    Udedibia, Emeka; Kaminetsky, Jed

    2014-12-01

    Hypogonadism is the most common endocrine disorder, which affects men of all age groups. Recent shifts in public awareness, increased screening and recognition of symptoms and updated diagnostic criteria have led to an increase in men diagnosed as hypogonadal, including middle-aged and older men who previously would have been considered eugonadal. The increase in testosterone replacement therapy (TRT) has paralleled an increase in advancements of treatment options. Although current therapies are highly efficacious for many men, there remains a need for newer therapies that are more cost-effective, preserve ease of use and administration, mitigate undesirable effects and closely mimic physiological levels of testosterone. In this review, the authors discuss current TRTs and therapies in development for the treatment of hypogonadism. The focus is on therapies under Phase II investigation or those who have recently completed Phase II study. With several new therapies in development, the authors expect advancements in achieving treatment benchmarks that meet the needs of the individual symptomatic hypogonadal male. Increased public awareness of hypogonadism and TRT has led to a welcomed expansion in the choice of TRT options. These include new delivery systems, formulations, routes of administration and non-testosterone modalities.

  10. The investigations of characteristics of Sb2Te as a base phase-change material

    Science.gov (United States)

    Liu, Guangyu; Wu, Liangcai; Zhu, Min; Song, Zhitang; Rao, Feng; Song, Sannian; Cheng, Yan

    2017-09-01

    Chalcogenide alloys are paid much attention in the study of nonvolatile phase-change memory (PCM). A comprehensive research is investigated on Sb2Te (ST), a base material, from properties to performances in this paper. For the characteristics of ST films, the sheet resistance is extremely stable during cooling process in resistance-temperature measurement and the thickness change of ST film is 5.7%. However, low 10-year data retention temperature (∼55 °C) and large crystal grain are the demerits for ST. In addition, the structure characteristics show stable hexagonal phase and large grain of several hundred nanometers at crystalline state after annealing. As for electrical properties, although the ST-based PCM devices are characterized by fast operation speed of ∼20 ns, only about 8 × 103 times of stable operation cycles can be obtained. After that, the endurance performance deteriorates gradually due to the growth of grains. About resistance drift, the drift coefficients are very small both in crystalline state and in amorphous state.

  11. Investigation of phase synchronization of interictal EEG in right temporal lobe epilepsy

    Science.gov (United States)

    Yu, Haitao; Cai, Lihui; Wu, Xinyu; Song, Zhenxi; Wang, Jiang; Xia, Zijie; Liu, Jing; Cao, Yibin

    2018-02-01

    Epilepsy is commonly associated with abnormally synchronous activity of neurons located in epileptogenic zones. In this study, we investigated the synchronization characteristic of right temporal lobe epilepsy (RTLE). Multichannel electroencephalography (EEG) data were recorded from the RTLE patients during interictal period and normal controls. Power spectral density was first used to analyze the EEG power for two groups of subjects. It was found that the power of epileptics is increased in the whole brain compared with that of the control. We calculated phase lag index (PLI) to measure the phase synchronization between each pair of EEG signals. A higher degree of synchronization was observed in the epileptics especially between distant channels. In particular, the regional synchronization degree was negatively correlated with power spectral density and the correlation was weaker for epileptics. Moreover, the synchronization degree decayed with the increase of relative distance of channels for both the epilepsy and control, but the dependence was weakened in the former. The obtained results may provide new insights into the generation mechanism of epilepsy.

  12. Investigation of In–48Sn as a phase change material candidate for thermal storage applications

    Directory of Open Access Journals (Sweden)

    Mawire Ashmore

    2017-01-01

    Full Text Available Latent heat storage systems provide large thermal storage densities for solar energy storage for various domestic and industrial applications. In–48Sn, an alloy of indium and tin a lead-free solder is investigated as a phase change material (PCM in latent heat storage systems for heating applications. Results obtained from differential scanning calorimetry indicate that the alloy is useful in storing sensible heat beyond its melting temperature as it exhibits very little decomposition up to 400 °C. Though In–48Sn possesses a low latent heat of fusion, its high density allows for a larger thermal storage mass. The behaviour of In–48Sn in a 50 mm aluminium spherical capsule during charging and discharging cycles is investigated using sunflower oil as the heat transfer fluid (HTF at flow rates of 3, 6, 9 and 12 ml/s. The influence of the charging temperature on the charging characteristics of the encapsulated PCM is also investigated. The average charging and discharging rates of the encapsulated PCM show an increase with an increase in the HTF flow rate. The HTF temperature determines the maximum temperature attained by the PCM and thus the total energy stored by the encapsulated PCM. In–48Sn shows good potential as a PCM in a spherical aluminium capsule for packed bed domestic heat storage systems.

  13. UPS and DFT investigation of the electronic structure of gas-phase trimesic acid

    Energy Technology Data Exchange (ETDEWEB)

    Reisberg, L., E-mail: rebban@ut.ee [Institute of Physics, University of Tartu, W. Oswaldi 1, EE-50411 Tartu (Estonia); Pärna, R. [Institute of Physics, University of Tartu, W. Oswaldi 1, EE-50411 Tartu (Estonia); MAX IV Laboratory, Lund University, Fotongatan 2, 225 94 Lund (Sweden); Kikas, A.; Kuusik, I.; Kisand, V. [Institute of Physics, University of Tartu, W. Oswaldi 1, EE-50411 Tartu (Estonia); Hirsimäki, M.; Valden, M. [Surface Science Laboratory, Optoelectronics Research Centre, Tampere University of Technology, FIN-33101 Tampere (Finland); Nõmmiste, E. [Institute of Physics, University of Tartu, W. Oswaldi 1, EE-50411 Tartu (Estonia)

    2016-11-15

    Highlights: • In the current study outer valence band electronic structure of benzene-1,3,5-tricarboxylic acid was interpreted. • Experimental and calculated trimesic acid (TMA) spectrum were compared to ones of benzene and benzoic acid. • It is shown that similarities between MO energies and shapes for benzene and TMA exists. • Addition of carboxyl groups to the benzene ring clearly correlates with increasing binding energy of HOMO. - Abstract: Benzene-1,3,5-tricarboxylic acid (trimesic acid, TMA) molecules in gas-phase have been investigated by using valence band photoemission. The photoelectron spectrum in the binding energy region from 9 to 22 eV is interpreted by using density functional theory calculations. The electronic structure of TMA is compared with benzene and benzoic acid in order to demonstrate changes in molecular orbital energies induced by addition of carboxyl groups to benzene ring.

  14. Investigation of the phase separation of PNIPAM using infrared spectroscopy together with multivariate data analysis

    DEFF Research Database (Denmark)

    Munk, Tommy; Baldursdottir, Stefania G.; Hietala, S.

    2013-01-01

    The use of vibrational spectroscopy to investigate complex structural changes in polymers yields chemically rich data, but interpretation can be challenging and subtle but meaningful spectral changes may be missed through visual inspection alone. Multivariate analysis is an efficient approach...... to gain an oversight of small but systematic spectral differences anywhere within the spectra, providing further insight into structural changes and associated transformation mechanisms. In this study, the novel analytical approach of infrared spectroscopy combined with principal component analysis...... a complex re-organization of the hydrogen bonds and change of the hydration layer. The changes agreed with existing results from other techniques, and new insights were gained into the effect of controlled tacticity on phase transformation behaviour. The study demonstrates that infrared spectroscopy...

  15. Optical investigation of gas-phase KCl/KOH sulfation in post flame conditions

    DEFF Research Database (Denmark)

    Weng, Wubin; chen, Shuang; Wu, Hao

    2018-01-01

    A counter-flow reactor setup was designed to investigate the gas-phase sulfation and homogeneous nucleation of potassium salts. Gaseous KOH and KCl were introduced into the post-flame zone of a laminar flat flame. The hot flame products mixed in the counter-flow with cold N2, with or without....... Depending on the potassium speciation in the inlet and the presence of SO2, they consisted of K2SO4, KCl, or K2CO3, respectively. The experiments showed that KOH was sulphated more readily than KCl, resulting in larger quantities of aerosols. The sulfation process in the counter-flow setup was simulated...... using a chemical kinetic model including a detailed subset for the Cl/S/K chemistry. Similar to the experimental results, much more potassium sulfate was predicted when seeding KOH compared to seeding KCl. For both KOH and KCl, sulfation was predicted to occur primarily through the reactions among...

  16. Thermal investigation of a phase change memory device at the nanoscale

    International Nuclear Information System (INIS)

    Battaglia, Jean-Luc; De, Indrayush; Saci, Abdelhak; Kusiak, Andrzej; Sousa, Véronique

    2016-01-01

    New technologies in non-volatile memories have been developed for several years based on phase-change alloys out of which, the most known is the Ge 2 Sb 2 Te 5 . The thermal investigation of the microelectronics device at cell scale is relevant since the heat transfer is the main limiting aspect for the optimal functioning of the device. More particularly, the thermal resistance at interfaces between the constitutive materials is of primary importance. We implemented a scanning thermal microscopy experiment in the 3D mode that allowed to fully characterizing the thermal properties of the cell at the nanoscale. The results lead to understand the 3D heat diffusion in the cell and more particularly the role of the vertical and horizontal interfaces. (paper)

  17. Experimental investigation on phase change materials as heating element for non-electric neonatal incubator

    Science.gov (United States)

    Matahari, Rho Natta; Putra, Nandy; Ariantara, Bambang; Amin, Muhammad; Prawiro, Erwin

    2017-02-01

    High number of preterm births is one of the issues in improving health standard. The effort to help premature babies is hampered by high cost of NICU care in hospital. In addition, uneven distribution of electricity to remote area made it hard to operate the incubator. Utilization of phase change material beeswax to non-electricity incubator as heating element becomes alternative option to save premature babies. The objective of this experiment is to investigate the most efficient mass of beeswax according to Indonesian National Standard to earn over time and ideal temperature of incubator. Experiment was performed using prototype incubator, which utilizes natural convection phenomenon in the heating process of incubator. Utilization of fin is to accelerate heat distribution in the incubator. Result of experiment showed that the most efficient mass of PCM is 3 kg, which has 2.45 hours of running time for maintaining temperature of incubator in range of 32-36 °C.

  18. Detailed investigation of proposed gas-phase syntheses of ammonia in dense interstellar clouds

    International Nuclear Information System (INIS)

    Herbst, E.; Defrees, D.J.; Mclean, A.D.; Molecular Research Institute, Palo Alto, CA; IBM Almaden Research Center, San Jose, CA)

    1987-01-01

    The initial reactions of the Herbst and Klemperer (1973) and the Dalgarno (1974) schemes (I and II, respectively) for the gas-phase synthesis of ammonia in dense interstellar clouds were investigated. The rate of the slightly endothermic reaction between N(+) and H2 to yield NH(+) and H (scheme I) under interstellar conditions was reinvestigated under thermal and nonthermal conditions based on laboratory data. It was found that the relative importance of this reaction in synthesizing ammonia is determined by how the laboratory data at low temperature are interpreted. On the other hand, the exothermic reaction between N and H3(+) to form NH2(+) + H (scheme II) was calculated to possess significant activation energy and, therefore, to have a negligible rate coefficient under interstellar conditions. Consequently, this reaction cannot take place appreciably in interstellar clouds. 41 references

  19. An Investigation of Rotorcraft Stability-Phase Margin Requirements in Hover

    Science.gov (United States)

    Blanken, Chris L.; Lusardi, Jeff A.; Ivler, Christina M.; Tischler, Mark B.; Hoefinger, Marc T.; Decker, William A.; Malpica, Carlos A.; Berger, Tom; Tucker, George E.

    2009-01-01

    A cooperative study was performed to investigate the handling quality effects from reduced flight control system stability margins, and the trade-offs with higher disturbance rejection bandwidth (DRB). The piloted simulation study, perform on the NASA-Ames Vertical Motion Simulator, included three classes of rotorcraft in four configurations: a utility-class helicopter; a medium-lift helicopter evaluated with and without an external slung load; and a large (heavy-lift) civil tiltrotor aircraft. This large aircraft also allowed an initial assessment of ADS-33 handling quality requirements for an aircraft of this size. Ten experimental test pilots representing the U.S. Army, Marine Corps, NASA, rotorcraft industry, and the German Aerospace Center (DLR), evaluated the four aircraft configurations, for a range of flight control stability-margins and turbulence levels, while primarily performing the ADS-33 Hover and Lateral Reposition MTEs. Pilot comments and aircraft-task performance data were analyzed. The preliminary stability margin results suggest higher DRB and less phase margin cases are preferred as the aircraft increases in size. Extra care will need to be taken to assess the influence of variability when nominal flight control gains start with reduced margins. Phase margins as low as 20-23 degrees resulted in low disturbance-response damping ratios, objectionable oscillations, PIO tendencies, and a perception of an incipient handling qualities cliff. Pilot comments on the disturbance response of the aircraft correlated well to the DRB guidelines provided in the ADS-33 Test Guide. The A D-3S3 mid-term response-to-control damping ratio metrics can be measured and applied to the disturbance-response damping ratio. An initial assessment of LCTR yaw bandwidth shows the current Level 1 boundary needs to be relaxed to help account for a large pilot off-set from the c.g. Future efforts should continue to investigate the applicability/refinement of the current ADS-33

  20. INVESTIGATION OF MAGNETIC MODE FOR 3-PHASE TRANSFORMER WITH SYMMETRICAL MAGNETIC CONDUCTOR OF FRAME DESIGN

    Directory of Open Access Journals (Sweden)

    A. A. Mazurenko

    2017-01-01

    Full Text Available Magnetic mode for 3-phase transformer with symmetrical magnetic conductor of frame design has been investigated on schematic model. The scheme consists of three non-linear coils having star-connection without zero wire. Weberampere characteristics correspond to similar parameters of separate frames of a magnetic conductor. It has been accepted that a magnetic flow of every frame is closed on itself without passing into other frame of the magnetic conductor. Electromagnetic state of equivalent diagram has been described by a system of differential equations which were solved with the help of MathCad program. Investigations have resulted in calculation of functions for magnetic frame induction and magnetizing current and their harmonic compositions; dependence of actual amplitude for magnetic field induction on amplitude of the main harmonic induction has been determined in the paper. While executing experiments it has been revealed the following: induction amplitude of the main harmonic in the magnetic field within frames of the magnetic conductor is higher in comparison with the design induction value by 15.5 %; due to non-linearity of weber-ampere characteristics in frames and properties of 3-phase system harmonic components, which are multiple of three, are initiated in the functions of magnetic induction for separate frames; high-order harmonics of function for magnetic frame induction being imposed on the main harmonic decrease an actual amplitude of magnetic field induction practically up to the design induction value within the operational range of the actual amplitude and in this context coefficients of high-order harmonics change insignificantly; harmonic components, which are multiple of three, are absent in magnetizing currents. 

  1. Investigation of Virtual Digital Human and Robotic Device Technology Merger Complimented by Haptics and Autostereoscopic Displays, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — As expected, the STTR Phase I investigation confirmed that the Digital Virtual Human (DVH) and Robonaut technologies can be merged, and that haptic and...

  2. Experimental investigation of flow accelerated corrosion under two-phase flow conditions

    International Nuclear Information System (INIS)

    Ahmed, Wael H.; Bello, Mufatiu M.; El Nakla, Meamer; Al Sarkhi, Abdelsalam; Badr, Hassan M.

    2014-01-01

    Highlights: • Effect of two-phase flow on flow accelerated corrosion has been investigated experimentally. • Experiments were performed for different orifice to pipe diameter ratios. • The effect of flow patterns and mass quality on wear patterns is investigated. • The maximum FAC wear was found at approximately 2–5 pipe diameters downstream of the orifice. • The current study will help FAC engineers to prepare reliable plant inspection scope. - Abstract: The main objective of this paper is to experimentally study the effect of two-phase flow on flow-accelerated corrosion (FAC) downstream an orifice. FAC is a major safety and reliability issue affecting carbon-steel piping in nuclear and fossil power plants. This is because of its pipe wall wearing and thinning effects that could lead to sudden and sometimes catastrophic failures, as well as a huge economic loss. In the present study, FAC wear of carbon-steel piping was simulated experimentally by circulating air–water mixtures through hydrocal (CaSO 4 ·1/2H 2 O) test sections at liquid superficial Reynolds number, Re = 20,000, and different air mass flow rates. Experiments were performed for a test section with different orifice to pipe diameter ratios (d o /D = 0.25, 0.5 and 0.74). The observed flow patterns were compared with the available flow pattern maps. Surface wear patterns downstream the orifices were also analyzed. The maximum FAC wear was found to occur at approximately 2–5 pipe diameters downstream of the orifice. The obtained results were found to be consistent with those from a single-phase flow study reported earlier. Moreover, FAC was found to depend on the relative values of the mixture mass quality and the volumetric void fraction. Lower values of FAC wear rate were obtained for higher values of mass quality. A modified correlation is developed in order to predict FAC wear rate downstream of the pipe-restricting orifice with an average RMS accuracy of ±10%. However, the location

  3. Phase II Investigation at the Former CCC/USDA Grain Storage Facility in Savannah, Missouri

    Energy Technology Data Exchange (ETDEWEB)

    LaFreniere, Lorraine M. [Argonne National Lab. (ANL), Argonne, IL (United States). Environmental Science Division. Applied Geosciences and Environmental Management Section

    2012-05-01

    contamination potentially associated with a number of former CCC/USDA grain storage facilities in Missouri. The site characterization at Savannah is being conducted on behalf of the CCC/USDA by the Environmental Science Division of Argonne National Laboratory. The investigation is being conducted in phases, so that information obtained and interpretations developed during each incremental stage can be used most effectively to guide subsequent phases of the program. Phase II objectives: Investigate the more detailed characteristics of groundwater flow in the vicinity of the former CCC/USDA facility and the contaminated Morgan and MoDOT private wells; Obtain additional information on the vertical and lateral distribution and concentrations of carbon tetrachloride in groundwater in the vicinity of the former CCC/USDA facility and the contaminated Morgan and MoDOT private wells; Investigate further for possible evidence of carbon tetrachloride in the subsurface (vadose zone) and deeper soils beneath the former CCC/USDA facility, as well as in the vicinity of the contaminated MoDOT private well.

  4. Hydrogeological characterization on surface-based investigation phase in the Mizunami underground research laboratory project, in Japan

    International Nuclear Information System (INIS)

    Saegusa, Hiromitsu; Onoe, Hironori; Takeuchi, Shinji; Takeuchi, Ryuji; Ohyama, Takuya

    2007-01-01

    The Mizunami Underground Research Laboratory (MIU) project is being carried out by Japan Atomic Energy Agency in the Cretaceous Toki granite in the Tono area, central Japan. The MIU project is a purpose-built generic underground research laboratory project that is planned for a broad scientific study of the deep geological environment as a basis of research and development for geological disposal of nuclear wastes. One of the main goals of the MIU project is to establish comprehensive techniques for investigation, analysis, and assessment of the deep geological environment. The MIU project has three overlapping phases: Surface-based Investigation (Phase I), Construction (Phase II) and Operation (Phase III). Hydrogeological investigations using a stepwise process in Phase I have been carried out in order to obtain information on important properties such as, location of water conducting features, hydraulic conductivity and so on. Hydrogeological modeling and groundwater flow simulations in Phase I have been carried out in order to synthesize these investigation results, to evaluate the uncertainty of the hydrogeological model and to identify the main issues for further investigations. Using the stepwise hydrogeological characterization approach and combining the investigation with modeling and simulation, understanding of the hydrogeological environment has been progressively improved. (authors)

  5. Experimental investigations on the cooling of a motorcycle helmet with phase change material (PCM

    Directory of Open Access Journals (Sweden)

    Fok S.C.

    2011-01-01

    Full Text Available The thermal comfort of motorcycle helmet during hot weather is important as it can affect the physiological and psychological condition of the rider. This paper examines the use of phase change material (PCM to cool a motorcycle helmet and presents the experimental investigations on the influences of the simulated solar radiation, wind speed, and heat generation rate on the cooling system. The result shows that the PCM-cooled helmet is able to prolong the thermal comfort period compared to a normal helmet. The findings also indicate that the heat generation from the head is the predominant factor that will affect the PCM melting time. Simulated solar radiation and ram-air due to vehicle motion under adiabatic condition can have very little influences on the PCM melting time. The results suggested that the helmet usage time would be influenced by the amount of heat generated from the head. Some major design considerations based on these findings have been included. Although this investigation focuses on the cooling of a motorcyclist helmet, the findings would also be useful for the development of PCM-cooling systems in other applications.

  6. [Environmental investigation of ground water contamination at Wright- Patterson Air Force Base, Ohio]. Volume 4, Health and Safety Plan (HSP); Phase 1, Task 4 Field Investigation report: Draft

    Energy Technology Data Exchange (ETDEWEB)

    1991-10-01

    This Health and Safety Plan (HSP) was developed for the Environmental Investigation of Ground-water Contamination Investigation at Wright-Patterson Air Force Base near Dayton, Ohio, based on the projected scope of work for the Phase 1, Task 4 Field Investigation. The HSP describes hazards that may be encountered during the investigation, assesses the hazards, and indicates what type of personal protective equipment is to be used for each task performed. The HSP also addresses the medical monitoring program, decontamination procedures, air monitoring, training, site control, accident prevention, and emergency response.

  7. Bedrock Hydrogeology - Site investigation SFR

    Energy Technology Data Exchange (ETDEWEB)

    Oehman, Johan [Geosigma AB, Stockholm (Sweden); Bockgaard, Niclas [Golder Assoes AB, Stockholm (Sweden); Follin, Sven [SF GeoLogic AB, Taeby (Sweden)

    2012-06-15

    The Swedish Nuclear Fuel and Waste Management Company (SKB) has conducted site investigations for a planned extension of the existing final repository for short-lived radioactive waste (SFR). This report presents an integrated analysis and interpretation of the historic data from the existing SFR (1980 - 1986), as well as, from the recent investigations for the planned extension of SFR (2008 - 2009). The primary objective is to establish a conceptual hydrogeological model of the bedrock for safety assessment and design analyses. Analyses and interpretations of all (old and new) hydraulic data are analysed with regard to the recently developed geological deformation zone model of the SFR model domain (Curtis et al. 2011). The methodology used by Curtis et al. (2011) has focussed on magnetic anomalies and deformation zone intercepts with ground surface greater than 300 m. In the hydrogeological modelling, however, it has been considered important to also explore the occurrence and characteristics of shallow horizontal to sub-horizontal structures (sheet joints) inside the SFR model domain. Such structures are of considerable importance for the hydrogeology in the uppermost c. 150 m of bedrock in SDM-Site Forsmark; hence the term Shallow Bedrock Aquifer was used to emphasise their hydraulic significance. In this study, the acronym SBA-structure is used for horizontal structures identified in the hydrogeological modelling. In addition to the predominantly steeply dipping geological deformation zones, eight so-called SBA-structures are modelled deterministically in the hydrogeological model. The SBA-structures are envisaged as hydraulically heterogeneous and composed of clusters of minor gently dipping to horizontal fractures rather than extensive single features. A type of structures that is partly included in the definition of the SBA-structures is the Unresolved Possible Deformations Zone (Unresolved PDZ) intercepts identified by Curtis et al. (2011). The Unresolved

  8. Investigations on the growth kinetics of Laves phase precipitates in 12% Cr creep-resistant steels: Experimental and DICTRA calculations

    Energy Technology Data Exchange (ETDEWEB)

    Prat, O. [Max Planck Institute fuer Eisenforschung GmbH, Max Planck Strasse 1, 40237 Duesseldorf (Germany)] [Universidad de Concepcion, Departamento de Ingenieria de Materiales, Edmundo Larenas 270, Concepcion (Chile); Garcia, J., E-mail: jose.garcia@helmholtz-berlin.de [Helmholtz-Zentrum Berlin fuer Materialien und Energie GmbH, Hahn-Meitner-Platz 1, 14109 Berlin (Germany); Rojas, D. [Max Planck Institute fuer Eisenforschung GmbH, Max Planck Strasse 1, 40237 Duesseldorf (Germany); Carrasco, C. [Universidad de Concepcion, Departamento de Ingenieria de Materiales, Edmundo Larenas 270, Concepcion (Chile); Inden, G. [Max Planck Institute fuer Eisenforschung GmbH, Max Planck Strasse 1, 40237 Duesseldorf (Germany)

    2010-10-15

    The growth kinetics of Laves phase precipitates (type Fe{sub 2}W) in the early stage of creep (650 deg. C for 10,000 h) in two 12% Cr ferrite-martensitic steels has been investigated. In one alloy the Laves phase formed on tempering, while in the second alloy the Laves phase precipitated during creep. Kinetic simulations were performed using the software DICTRA. The particle size of the Laves phase was measured on transmission electron microscopy samples. The equilibrium phase fraction of the Laves phase was reached in the first thousand hours. Simulations of particle growth showed good agreement with the experimental results. Competitive growth between M{sub 23}C{sub 6} and the Laves phase showed that M{sub 23}C{sub 6} carbides reached their equilibrium after 12 days, whereas the Laves phase reached equilibrium after 3 months. Simulations of the influence of the interfacial energy and addition of Co, Cu and Si on Laves phase precipitation are presented.

  9. Phase 1 remedial investigation report for 200-BP-1 operable unit. Volume 1

    Energy Technology Data Exchange (ETDEWEB)

    1993-09-01

    The US Department of Energy (DOE) Hanford Site, in Washington State is organized into numerically designated operational areas including the 100, 200, 300, 400, 600, and 1100 Areas. The US Environmental Protection Agency (EPA), in November 1989 included the 200 Areas of the Hanford Site on the National Priority List (NPL) under the Comprehensive Environmental Response, Compensation and Liability Act of 1980 (CERCLA). Inclusion on the NPL initiated the remedial investigation (RD process for the 200-BP-1 operable unit. These efforts are being addressed through the Hanford Federal Facility Agreement and Consent Order (Ecology et al. 1989) which was negotiated and approved by the DOE, the EPA, and the State of Washington Department of Ecology (Ecology) in May 1989. This agreement, known as the Tri-Party Agreement, governs all CERCLA efforts at Hanford. In March of 1990, the Department of Energy, Richland Operations (DOE-RL) issued a Remedial Investigation/Feasibility Study (RI/FS) work plan (DOE-RL 1990a) for the 200-BP-1 operable unit. The work plan initiated the first phase of site characterization activities associated with the 200-BP-1 operable unit. The purpose of the 200-BP-1 operable unit RI is to gather and develop the necessary information to adequately understand the risks to human health and the environment posed by the site and to support the development and analysis of remedial alternatives during the FS. The RI analysis will, in turn, be used by Tri-Party Agreement signatories to make a risk-management-based selection of remedies for the releases of hazardous substances that have occurred from the 200-BP-1 operable unit.

  10. Phase 1 remedial investigation report for 200-BP-1 operable unit

    International Nuclear Information System (INIS)

    1993-09-01

    The US Department of Energy (DOE) Hanford Site, in Washington State is organized into numerically designated operational areas including the 100, 200, 300, 400, 600, and 1100 Areas. The US Environmental Protection Agency (EPA), in November 1989 included the 200 Areas of the Hanford Site on the National Priority List (NPL) under the Comprehensive Environmental Response, Compensation and Liability Act of 1980 (CERCLA). Inclusion on the NPL initiated the remedial investigation (RD process for the 200-BP-1 operable unit. These efforts are being addressed through the Hanford Federal Facility Agreement and Consent Order (Ecology et al. 1989) which was negotiated and approved by the DOE, the EPA, and the State of Washington Department of Ecology (Ecology) in May 1989. This agreement, known as the Tri-Party Agreement, governs all CERCLA efforts at Hanford. In March of 1990, the Department of Energy, Richland Operations (DOE-RL) issued a Remedial Investigation/Feasibility Study (RI/FS) work plan (DOE-RL 1990a) for the 200-BP-1 operable unit. The work plan initiated the first phase of site characterization activities associated with the 200-BP-1 operable unit. The purpose of the 200-BP-1 operable unit RI is to gather and develop the necessary information to adequately understand the risks to human health and the environment posed by the site and to support the development and analysis of remedial alternatives during the FS. The RI analysis will, in turn, be used by Tri-Party Agreement signatories to make a risk-management-based selection of remedies for the releases of hazardous substances that have occurred from the 200-BP-1 operable unit

  11. Application of 119Sn Moessbauer spectroscopy to investigations of RET2-X2-type phases

    International Nuclear Information System (INIS)

    Goerlich, E.

    1991-01-01

    Moessbauer spectroscopy of 119 Sn is an effective tool to study nuclear hyperfine interactions which in turn are important as a source of information complementary to that supplied by ''classical'' methods. However, particularly when the effects are subtle, experimental conditions as well as data analysis should be handled with care. The attention is devoted primarily to the finite absorber thickness effects. As examples serve our recent results obtained from investigations of ternary tetragonal phases of RET 2 X 2 -type. In EuPd 2 Si 2 mixed valent system 119 Sn was used as probe which detects the influence of Eu-valency change at a distant site of Si. Electrical resistivity measurements in CeNi 2 Sn 2 may indicate a Kondo-type behaviour while Moessbauer effect leads to the conclusion in favour of a magnetically ordered state. The analysis of resonance absorption spectra of CeAg 2 Sn 2 using a full transmission integral indicates the presence of a metallic β-tin in the sample, while data fitting within the thin absorber approximation has lead to the opposite conclusion. Neither in CeNi 2 Sn 2 nor in ErNi 2 Sn 2 the temperature dependence of the recoil free factors alone cannot explain the observed broadening of spectra at low temperatures. (author). 14 refs, 13 figs

  12. Investigating hyperoxic effects in the rat brain using quantitative susceptibility mapping based on MRI phase.

    Science.gov (United States)

    Hsieh, Meng-Chi; Kuo, Li-Wei; Huang, Yun-An; Chen, Jyh-Horng

    2017-02-01

    To test whether susceptibility imaging can detect microvenous oxygen saturation changes, induced by hyperoxia, in the rat brain. A three-dimensional gradient-echo with a flow compensation sequence was used to acquire T2*-weighted images of rat brains during hyperoxia and normoxia. Quantitative susceptibility mapping (QSM) and QSM-based microvenous oxygenation venography were computed from gradient-echo (GRE) phase images and compared between the two conditions. Pulse oxygen saturation (SpO 2 ) in the cortex was examined and compared with venous oxygen saturation (SvO 2 ) estimated by QSM. Oxygen saturation change calculated by a conventional Δ R2* map was also compared with the ΔSvO 2 estimated by QSM. Susceptibilities of five venous and tissue regions were quantified separately by QSM. Venous susceptibility was reduced by nearly 10%, with an SvO 2 shift of 10% during hyperoxia. A hyperoxic effect, confirmed by SpO 2 measurement, resulted in an SvO 2 increase in the cortex. The ΔSvO 2 between hyperoxia and normoxia was consistent with what was estimated by the Δ R2* map in five regions. These findings suggest that a quantitative susceptibility map is a promising technique for SvO 2 measurement. This method may be useful for quantitatively investigating oxygenation-dependent functional MRI studies. Magn Reson Med 77:592-602, 2017. © 2016 International Society for Magnetic Resonance in Medicine. © 2016 International Society for Magnetic Resonance in Medicine.

  13. Experimental investigation of the dissolution of fractures. From early stage instability to phase diagram

    Science.gov (United States)

    Osselin, Florian; Budek, Agnieszka; Cybulski, Olgierd; Kondratiuk, Pawel; Garstecki, Piotr; Szymczak, Piotr

    2016-04-01

    Dissolution of natural rocks is a fundamental geological process and a key part of landscape formation and weathering processes. Moreover, in current hot topics like Carbon Capture and Storage or Enhanced Oil Recovery, mastering dissolution of the host rock is fundamental for the efficiency and the security of the operation. The basic principles of dissolution are well-known and the theory of the reactive infiltration instability has been extensively studied. However, the experimental aspect has proved very challenging because of the strong dependence of the outcome with pore network, chemical composition, flow rate... In this study we are trying to tackle this issue by using a very simple and efficient device consisting of a chip of pure gypsum inserted between two polycarbonate plates and subjected to a constant flow rate of pure water. Thanks to this device, we are able to control all parameters such as flow rate, fracture aperture, roughness of the walls... but also to observe in situ the progression of the dissolution thanks to the transparency of the polycarbonate which is impossible with 3D rocks. We have been using this experimental set-up to explore and investigate all aspects of the dissolution in a fracture, such as initial instability and phase diagram of different dissolution patterns, and to compare it with theory and simulations, yielding very good agreement and interesting feedbacks on the coupling between flow and chemistry in geological media

  14. Magnetic phase investigations on fluorine (F) doped LiFePO4

    Science.gov (United States)

    Radhamani, A. V.

    2018-03-01

    LiFePO4 (LFP) is a very promising cathode material for Li-ion batteries due to its high thermal stability, less toxicity and high theoretical capacity (170 mAh g-1). Anion doping, especially fluorine (F) at the oxygen site is one way to improve the low electronic conductivity of the material. In this line, fluorine doped LFP was prepared at different fluorine concentrations (1 to 40 mol%) to study the structural, spectroscopic and magnetic properties in view of the material property optimization for battery applications. The investigation of the magnetic properties was found to be successful for the determination of small amounts of magnetic impurities which were not noticeably observed from structural characterizations. Determination of conducting magnetic impurities has its own relevance in the current scenario of Li-ion based battery applications. Systematic characterization studies along with the implications of magnetic phases on the material activity of fluorine doped LiFePO4 nanoparticles will be discussed in detail.

  15. Monte Carlo based investigation of Berry phase for depth resolved characterization of biomedical scattering samples

    Energy Technology Data Exchange (ETDEWEB)

    Baba, Justin S [ORNL; John, Dwayne O [ORNL; Koju, Vijay [ORNL

    2015-01-01

    The propagation of light in turbid media is an active area of research with relevance to numerous investigational fields, e.g., biomedical diagnostics and therapeutics. The statistical random-walk nature of photon propagation through turbid media is ideal for computational based modeling and simulation. Ready access to super computing resources provide a means for attaining brute force solutions to stochastic light-matter interactions entailing scattering by facilitating timely propagation of sufficient (>10million) photons while tracking characteristic parameters based on the incorporated physics of the problem. One such model that works well for isotropic but fails for anisotropic scatter, which is the case for many biomedical sample scattering problems, is the diffusion approximation. In this report, we address this by utilizing Berry phase (BP) evolution as a means for capturing anisotropic scattering characteristics of samples in the preceding depth where the diffusion approximation fails. We extend the polarization sensitive Monte Carlo method of Ramella-Roman, et al.,1 to include the computationally intensive tracking of photon trajectory in addition to polarization state at every scattering event. To speed-up the computations, which entail the appropriate rotations of reference frames, the code was parallelized using OpenMP. The results presented reveal that BP is strongly correlated to the photon penetration depth, thus potentiating the possibility of polarimetric depth resolved characterization of highly scattering samples, e.g., biological tissues.

  16. Investigation of two-phase thermosyphon performance filled with modern HFC refrigerants

    Science.gov (United States)

    Gorecki, Grzegorz

    2018-02-01

    Two-phase closed thermosyphons (TPCTs) are widely utilized as heat exchanger elements in waste heat recovery systems and as passive heating/cooling devices. They are popular because of their high thermal conductivity, simple construction and reliability. Previous researches indicate that refrigerants are performing better than typical TPCT working fluids like deionized water or alcohols in the low temperature range. In the present study three HFC (Hydrofluorocarbons) refrigerants were tested: R134a, R404A and R407C. The total length of the investigated TPCT is 550 mm with equal length (245 mm) condenser and evaporator sections. Its outer diameter is 22 mm with 1 mm wall thickness. The evaporator section was heated by hot water with varying inlet temperature by 5 K step in the range of 288 K - 323 K. The condenser was cooled by cold water with inlet temperature kept at a constant value of 283 K. It was found that using R134a and R404A as working fluids heat transfer rates are the highest. For both refrigerants 10% is optimal filling ratio. They can be utilized interchangeably because the differences between their throughputs are within uncertainty bands. R407C performance was 50% lower. Other disadvantages of using this refrigerant are relatively high working pressures and higher optimal filling ratio (30%).

  17. Experimental investigation of solidification in metal foam enhanced phase change material

    Science.gov (United States)

    Beyne, W.; Bağci, O.; Huisseune, H.; Canière, H.; Danneels, J.; Daenens, D.; De Paepe, M.

    2017-10-01

    A major challenge for the use of phase change materials (PCMs) in thermal energy storage (TES) is overcoming the low thermal conductivity of PCM’s. The low conductivity gives rise to limited power during charging and discharging TES. Impregnating metal foam with PCM, however, has been found to enhance the heat transfer. On the other hand, the effect of foam parameters such as porosity, pore size and material type has remained unclear. In this paper, the effect of these foam parameters on the solidification time is investigated. Different samples of PCM-impregnated metal foam were experimentally tested and compared to one without metal foam. The samples varied with respect to choice of material, porosity and pore size. They were placed in a rectangular cavity and cooled from one side using a coolant flowing through a cold plate. The other sides of the rectangular cavity were Polymethyl Methacrylate (PM) walls exposed to ambient. The temperature on the exterior walls of the cavity was monitored as well as the coolant flow rate and its temperature. The metal foam inserts reduced the solidification times by at least 25 %. However, the difference between the best performing and worst performing metal foam is about 28 %. This shows a large potential for future research.

  18. Small angle neutron scattering form polymer melts: structural investigation and phase behaviour

    International Nuclear Information System (INIS)

    Ertugrul, O.

    2004-01-01

    The Small-Angle Neutron Scattering (SANS) techniques have been used to study the structural properties and phase behavior of polymer melts. A model based on Random Phase Approximation (RPA) is proposed to predict the experimental data. By fitting the model to data we could be able to obtain radius of gyration (a measure of size of a polymer) and phase transition for the sample. (author)

  19. Model investigations 3D of gas-powder two phase flow in descending packed bed in metallurgical shaft furnaces

    OpenAIRE

    B. Panic; K. Janiszewski

    2014-01-01

    This paper presents the second phase of model investigations of static pressure radial distribution conducted on 4 levels of bed height. During the phase the diameter of glass bed particles was increased, blast-furnace pellets were introduced as bed and iron powder was used as powder. Experiments were carried out with regard to gas velocity, bed and powder type and size of bed particles. The radial distribution of 3 fractions of powder accumulated in the bed – static powder, dynamic powder an...

  20. Investigational drugs in phase I and phase II clinical trials for the treatment of community-acquired pneumonia.

    Science.gov (United States)

    Liapikou, Adamantia; Cillóniz, Catia; Torres, Antoni

    2017-11-01

    Community acquired pneumonia is one of the main infections, remaining as a global cause of considerable morbidity and mortality. Successful treatment hinges on expedient delivery of appropriate antibiotic therapy tailored to both the likely pathogens and the severity of disease. Although antibiotic resistance is increasing and pharmaceutical companies continue to debate the profitability of introducing new antibacterial agents, an encouraging number of new molecules have recently been unveiled which target multidrug-resistant bacteria. Areas covered: Herein, the authors summarize the actual situation of novel antibiotics for CAP in phase I & II of development. For each set of compounds, the medical significance and possible clinical placement are discussed. Current treatment options from the most important international guidelines are also reviewed. Expert opinion: Our review shows that the new antibiotics in the pipeline belong to existing antibiotic classes as β-lactams, macrolides, quinolones, oxazolidinones, tetracyclines, lipoglycopeptides, and cyclic lipopeptides and a few with a narrow spectrum of activity are novel compounds directed against novel targets. With rising outpatient antibiotic resistance in pneumonia, some of the compounds discussed are being considered for more rapid advancement in the pipeline, helping to increase the number of agents in later stages of development.

  1. Radiotracer investigations to study the hydrodynamic characteristics of continuous phase in a pulsed sieve plate extraction column

    Science.gov (United States)

    Din, G. U.; Khan, I. H.; Chughtai, I. R.; Inayat, M. H.; Jin, J. H.

    2013-05-01

    The present investigations are focused to study the hydrodynamic characteristics of continuous phase in a pulsed sieve plate extraction column using 68Ga in the form of gallium chloride from an industrial radionuclide generator (68Ge/68Ga). Labeling of water with the subject radiotracer in water-kerosene environment was evaluated. Experiments for Residence Time Distribution (RTD) analysis were carried out for a range of dispersed phase superficial velocities in a liquid-liquid extraction pulsed sieve plate column operating in the emulsion regime with water as continuous and kerosene as dispersed phase. Axial Dispersion Model (ADM) was used to simulate the hydrodynamic characteristics of continuous phase. It has been observed that the axial mixing in the continuous phase decreases and slip velocity increases with increase in superficial velocity of dispersed phase while the holdup of continuous phase was found to decrease with increase in superficial velocity of dispersed phase. ADM with open-open boundary condition was found to be a suitable model for the subject system.

  2. Experimental Investigations of Noise Control in Planetary Gear Set by Phasing

    Directory of Open Access Journals (Sweden)

    S. H. Gawande

    2014-01-01

    Full Text Available Now a days reduction of gear noise and resulting vibrations has received much attention of the researchers. The internal excitation caused by the variation in tooth mesh stiffness is a key factor in causing vibration. Therefore to reduce gear noise and vibrations several techniques have been proposed in recent years. In this research the experimental work is carried out to study the effect of planet phasing on noise and subsequent resulting vibrations of Nylon-6 planetary gear drive. For this purpose experimental set-up was built and trials were conducted for two different arrangements (i.e., with phasing and without phasing and it is observed that the noise level and resulting vibrations were reduced by planet phasing arrangement. So from the experimental results it is observed that by applying the meshing phase difference one can reduce planetary gear set noise and vibrations.

  3. Grimsel test site. Investigation phase IV. Borehole sealing. Technical report 07-01

    International Nuclear Information System (INIS)

    Bluemling, P.; Adams, J.

    2008-04-01

    Within the context of the phase IV (1994 - 1996) research and development activities at the Grimsel Test Site (GTS), Nagra developed, in collaboration with the 'Agence nationale pour la gestion des dechets radioactifs' (Andra), an investigation project for the sealing of boreholes drilled from underground. The project had the following goals: (i) sealing of boreholes drilled from underground facilities with a length of up to 500 m; (ii) sealing of boreholes with mainly irregular shape (e.g. breakouts of borehole wall); (iii) ensuring a hydraulic conductivity of 10 -11 - 10 -12 m/s for the seal; (iv) ensuring reliable quality control in routine production. Nagra's new concept developed in this project was to use highly compacted bentonite pellets or granular bentonite while Andra evaluated the use of a cylindrical block of bentonite. This report deals with Nagra's concepts only. The two techniques tested by Nagra were: 1. Pneumatic injection of granular bentonite into a borehole using a grain size distribution of 4-10 mm. 2. Emplacement using a modified core barrel (MACMET tool) for transport and compaction of bentonite pellets. Following a detailed literature study and the development of appropriate concepts, the necessary tools were developed and successively tested in the laboratory. An appropriate test field was established and characterized at GTS where both techniques were tested in situ to estimate their performance under realistic field conditions. The swelling pressures were monitored for 4 months after seal emplacement until an almost constant value was attained. Finally, the hydraulic and mechanical performances of the seals were tested. It was found that the conductivities measured across the seal were at least equivalent to the matrix properties of the surrounding rock (3-6·10 -12 m/s). The hydraulic testing also showed no linear preferential flow along the seals. (author)

  4. ICP Monitoring and Phase-Contrast MRI to Investigate Intracranial Compliance.

    Science.gov (United States)

    Lokossou, A; Balédent, O; Garnotel, S; Page, G; Balardy, L; Czosnyka, Z; Payoux, P; Schmidt, E A

    2018-01-01

    The amplitude of intracranial pressure (ICP) can be measured by ICP monitoring. Phase-contrast magnetic resonance imaging (PCMRI) can quantify blood and cerebrospinal fluid (CSF) flows. The aim of this work was to investigate intracranial compliance at rest by combining baseline ICP monitoring and PCMRI in hydrocephalus patients. ICP monitoring was performed before infusion testing to quantify ΔICP_rest at the basal condition in 33 suspected hydrocephalus patients (74 years). The day before, patients had had a PCMRI to assess total cerebral blood flow (tCBF), intracranial blood volume change (stroke volume SVblood), and cervical CSF volume change (the stroke volume CSV). Global (blood and CSF) intracranial volume change (ΔIVC) during each cardiac cycle (CC) was calculated. Finally, Compliance: C_rest = ΔIVC/ΔICP_rest was calculated. The data set was postprocessed by two operators according to blind analysis. Bland-Altman plots showed that measurements presented no significant difference between the two operators. ΔICP_rest = 2.41 ± 1.21 mmHg, tCBF = 469.89 ± 127.54 mL/min, SVblood = 0.82 ± 0.32 mL/cc, CSV = 0.50 ± 0.22 mL/cc, ΔIVC = 0.44 ± 0.22 mL, and C_rest = 0.23 ± 0.15 mL/mmHg. There are significant relations between SVblood and CSV and also SVblood and tCBF. During "basal" condition, the compliance amplitude of the intracranial compartment is heterogeneous in suspected hydrocephalus patients, and its value is lower than expected! This new parameter could represent new information, complementary to conventional infusion tests. We hope that this information can be applied to improve the selection of patients for shunt surgery.

  5. [Environmental investigation of ground water contamination at Wright-Patterson Air Force Base, Ohio]. Volume 3, Sampling and analysis plan (SAP): Phase 1, Task 4, Field Investigation: Draft

    Energy Technology Data Exchange (ETDEWEB)

    1991-10-01

    In April 1990, Wright-Patterson Air Force Base (WPAFB), initiated an investigation to evaluate a potential Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) removal action to prevent, to the extent practicable, the offsite migration of contaminated ground water from WPAFB. WPAFB retained the services of the Environmental Management Operations (EMO) and its principle subcontractor, International Technology Corporation (IT) to complete Phase 1 of the environmental investigation of ground-water contamination at WPAFB. Phase 1 of the investigation involves the short-term evaluation and potential design for a program to remove ground-water contamination that appears to be migrating across the western boundary of Area C, and across the northern boundary of Area B along Springfield Pike. Primarily, Task 4 of Phase 1 focuses on collection of information at the Area C and Springfield Pike boundaries of WPAFB. This Sampling and Analysis Plan (SAP) has been prepared to assist in completion of the Task 4 field investigation and is comprised of the Quality Assurance Project Plan (QAPP) and the Field Sampling Plan (FSP).

  6. Investigation of flow dynamics of liquid phase in a pilot-scale trickle bed reactor using radiotracer technique.

    Science.gov (United States)

    Pant, H J; Sharma, V K

    2016-10-01

    A radiotracer investigation was carried out to measure residence time distribution (RTD) of liquid phase in a trickle bed reactor (TBR). The main objectives of the investigation were to investigate radial and axial mixing of the liquid phase, and evaluate performance of the liquid distributor/redistributor at different operating conditions. Mean residence times (MRTs), holdups (H) and fraction of flow flowing along different quadrants were estimated. The analysis of the measured RTD curves indicated radial non-uniform distribution of liquid phase across the beds. The overall RTD of the liquid phase, measured at the exit of the reactor was simulated using a multi-parameter axial dispersion with exchange model (ADEM), and model parameters were obtained. The results of model simulations indicated that the TBR behaved as a plug flow reactor at most of the operating conditions used in the investigation. The results of the investigation helped to improve the existing design as well as to design a full-scale industrial TBR for petroleum refining applications. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. Low-Frequency, All Digital Radar (ADR) for Biomass and Ice-sheet Investigations, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Low-Frequency, All Digital Radar (ADR) can be a key component for NASA Phased-array and tomographic Radar systems spanning multiple earth-science measurement...

  8. Experimental investigation of zero phase shift effects for Coriolis flowmeters due to pipe imperfections

    DEFF Research Database (Denmark)

    Enz, Stephanie; Thomsen, Jon Juel; Neumeyer, Stefan

    2011-01-01

    damping and mass, and on ambient temperature changes. Experimental observations confirm the hypothesis that asymmetry in the axial distribution of damping will induce zero shifts similar to the phase shifts due to fluid flow. Axially symmetrically distributed damping was observed to influence phase shift......, the flexural vibrations of two bent, parallel, non-fluid-conveying pipes are studied experimentally, employing an industrial CFM. Special attention has been paid on the phase shift in the case of zero mass flow, i.e. the zero shift, caused by various imperfections to the ‘‘perfect’’ CFM, i.e. non-uniform pipe...... at an order of magnitude smaller than the primary effect of mass flow, while small added mass and ambient temperature changes induced zero shifts two orders of magnitude smaller than the phase shifts due to mass flow. The order of magnitude of the induced zero shifts indicates that non-uniform damping, added...

  9. Pyridinium salt investigations under high pressure: pressure-induced phase transitions in ferroelectric pyridinium perrhenate

    International Nuclear Information System (INIS)

    Czarnecki, P; Beskrovny, A I; Bobrowicz-Sarga, L; Lewicki, S; Wasicki, J

    2005-01-01

    The properties of pyridinium perrhenate have been studied by three methods: dielectric spectroscopy, neutron powder diffractometry and NMR spectrometry under high pressure. It has been shown that under high pressure the temperatures of the two phase transitions in the crystal are shifted towards lower ones. Moreover, the results have shown the occurrence of a new high pressure phase with a triple point corresponding to the pressure of 100 MPa and the temperature of 240 K

  10. Investigation on frictional pressure drop of steam-water two-phase flow in an internally ribbed tube

    International Nuclear Information System (INIS)

    Li Yongxing; Chen Tingkuan; Li Huixiong

    2005-01-01

    Within the range of pressures from 9 to 22 MPa, mass velocities from G 600 to 1200 kg/(m 2 ·s), and heat fluxes from x 0 to 1.0, experiments had performed to investigate the frictional pressure drop of the steam-water two-phase flow in a six-head internally ribbed tube with the outer diameter of 38.1 mm and the thickness of 7.5 mm. The test section was thermally insulated as horizontal direction. Based on the experimental results, it was found that pressure had a noticeable effect on the frictional pressure drop of the mental results, and that pressure had a noticeable effect on the frictional pressure drop of the steam-water two-phase flow, and the frictional pressure drop factor of the steam-water two-phase flow decreased with an increase in pressure. The frictional pressure drop factor of the steam-water two-phase flow tends to one near the critical pressure. As steam quality increased, the frictional pressure drop factor of the steam-water two-phase flow first increased, and then it had a decreasing tendency. With an increase in mass velocity, the frictional pressure drop factor of the steam-water two-phase flow decreased. Correlations of the frictional pressure drop factor of the steam-water two-phase flow had been provided. (authors)

  11. Pressure-induced phase transition in hydrothermally grown ZnO nanoflowers investigated by Raman and photoluminescence spectroscopy.

    Science.gov (United States)

    Bushiri, M Junaid; Vinod, R; Segura, Alfredo; Sans, Juan Angel

    2015-09-30

    This paper reports the pressure-dependent photoluminescence and Raman spectral investigation of hydrothermally synthesized ZnO nanoflowers at room temperature. Intrinsic near-band-edge UV emission from ZnO nanoflowers is monotonously blue-shifted under pressures up to 13.8 GPa with a pressure coefficient of 26 meV GPa(-1), and this pressure value is nearly 5 GPa above the transition pressure from the wurtzite to the rock salt phase for bulk ZnO. The Raman band corresponds to the wurtzite phase, the [Formula: see text] and [Formula: see text] modes were observed up to about 11 GPa from the spectra. The apparent discrepancy in the transition pressures as determined from photoluminescence and Raman studies suggests that it is a consequence of the gradual phase transition, in which the smallest nanoparticles are expected to remain in the wurtzite phase up to 13-15 GPa.

  12. Direct investigations of the immobilization of radionuclides in the alteration phases of spent nuclear fuel. 1998 annual progress report

    International Nuclear Information System (INIS)

    Burns, P.C.; Finch, R.J.

    1998-01-01

    'In an oxidizing environment, such as in the proposed repository at Yucca Mountain, rapid alteration rates are expected for spent nuclear fuel. Lab.-scale simulations have repeatedly shown that the dominant alteration products under repository conditions will be uranyl phases. There is an inadequate database that relates to the effects of the alteration products on the release of radionuclides, but this information is essential to provide a radionuclide release estimate. It is likely that many of the radionuclides contained in the fuel will be incorporated into the alteration products that form, potentially with a profound impact on the future mobility of radionuclides in the repository. The authors objective is to characterize the incorporation of radionuclides into alteration products by synthesis of uranyl phases doped with radionuclides, appropriate surrogate elements, or non-radioactive isotopes, followed by detailed phase characterization by diffraction and spectroscopic techniques. The research will permit a more realistic estimate of the release rates of the radionuclides from the near-field environment. This report summarizes work after 8 months of a 3-year project. The objective of investigating radionuclide incorporation in uranyl phases has required the development of synthesis techniques for various uranyl phases that are expected to form under repository conditions. The authors have synthesized and determined the structures of several uranyl phases that are new to science and that may be important alteration products under repository conditions. They have also undertaken the determination and refinement of the crystal structures of various uranyl phases that are likely to form under repository conditions. Other experiments include the investigation of the ion-exchange properties of uranyl phases under repository conditions.'

  13. Experimental investigation of the ternary system Ni–Pd–Sn with special focus on the B8-type phase

    International Nuclear Information System (INIS)

    Jandl, Isabella; Ipser, Herbert; Richter, Klaus W.

    2015-01-01

    The ternary alloy system Ni–Pd–Sn was investigated experimentally from 700 °C upwards, with special focus on the general NiAs-type compounds. The phase diagram and crystallographic parameters were studied by means of powder X-ray diffraction (XRD), differential thermal analysis (DTA), light optical microscopy (LOM) and scanning electron microscopy (SEM) in combination with energy dispersive X-ray spectroscopy (EDX). An isothermal section at 700 °C was constructed wherein a continuous phase field between the binary NiAs-type compounds γ (PdSn) and Ni 3 Sn 2 (high temperature modification) was detected. A series of samples throughout this phase field was used to investigate lattice parameter variations, occupation of the atomic sites and the melting behaviour. A partial ordering of the transition metals was observed. Moreover, three vertical sections at 30 at.%, 40 at.% and 50 at.% Sn were determined. Altogether, seven ternary invariant phase reactions were discovered: two ternary eutectic reactions, one ternary eutectoid reaction, three ternary transition reactions and one maximum. A complete reaction scheme for the investigated temperature range is given. Furthermore, a partial liquidus surface projection, except for the low-temperature Sn-rich region, was developed. - Highlights: • Detailed study of the ternary alloy system Ni–Pd–Sn. • 1 Isotherm, 3 vertical sections, a partial liquidus projection and a reaction scheme. • A continuous phase field, between γ and Ni 3 Sn 2 , was discovered. • Lattice parameters and structural features in this phase field were analysed. • A partial order of Ni and Pd in this phase field was observed

  14. Investigation of global particulate nitrate from the AeroCom phase III experiment

    Directory of Open Access Journals (Sweden)

    H. Bian

    2017-11-01

    Full Text Available An assessment of global particulate nitrate and ammonium aerosol based on simulations from nine models participating in the Aerosol Comparisons between Observations and Models (AeroCom phase III study is presented. A budget analysis was conducted to understand the typical magnitude, distribution, and diversity of the aerosols and their precursors among the models. To gain confidence regarding model performance, the model results were evaluated with various observations globally, including ground station measurements over North America, Europe, and east Asia for tracer concentrations and dry and wet depositions, as well as with aircraft measurements in the Northern Hemisphere mid-to-high latitudes for tracer vertical distributions. Given the unique chemical and physical features of the nitrate occurrence, we further investigated the similarity and differentiation among the models by examining (1 the pH-dependent NH3 wet deposition; (2 the nitrate formation via heterogeneous chemistry on the surface of dust and sea salt particles or thermodynamic equilibrium calculation including dust and sea salt ions; and (3 the nitrate coarse-mode fraction (i.e., coarse/total. It is found that HNO3, which is simulated explicitly based on full O3-HOx-NOx-aerosol chemistry by all models, differs by up to a factor of 9 among the models in its global tropospheric burden. This partially contributes to a large difference in NO3−, whose atmospheric burden differs by up to a factor of 13. The atmospheric burdens of NH3 and NH4+ differ by 17 and 4, respectively. Analyses at the process level show that the large diversity in atmospheric burdens of NO3−, NH3, and NH4+ is also related to deposition processes. Wet deposition seems to be the dominant process in determining the diversity in NH3 and NH4+ lifetimes. It is critical to correctly account for contributions of heterogeneous chemical production of nitrate on dust and sea salt, because this process

  15. Heat transfer characteristics of thermal energy storage of a composite phase change materials: Numerical and experimental investigations

    International Nuclear Information System (INIS)

    Aadmi, Moussa; Karkri, Mustapha; El Hammouti, Mimoun

    2014-01-01

    In the present study, phase change materials based on epoxy resin paraffin wax with the melting point 27 °C were used as a new energy storage system. Thermophysical properties and the process of melting of a PCM (phase change material) composite were investigated numerically and experimentally. DSC (differential scanning calorimetry) has been used for measurement of melting enthalpy and determination of PCM heat capacity. The thermophysical properties of the prepared composite have been characterized by using a new transient hot plate apparatus. The results have shown that the most important thermal properties of these composites at the solid and liquid states are like the “apparent” thermal conductivity, the heat storage capacity and the latent heat of fusion. These experimental results have been simulated by using numerical Comsol ® Multiphysiques 4.3 based models with success. The results of the experimental investigation compare favorably with the numerical results and thus serve to validate the numerical approach. - Highlights: • Phase change materials based on paraffin spheres used as new energy storage system. • Thermophysical properties and the melting process of composites were investigated. • All experimental results have been simulated using Comsol ® Multiphysiques. • The ability to store and release the thermal energy were investigated. • A very thin molten PCM (phase change material) exists which is apparently visible in the spheres

  16. 78 FR 13379 - Xanthan Gum from Austria and China; Scheduling of the Final Phase of an Antidumping Investigation

    Science.gov (United States)

    2013-02-27

    ... Austria and China; Scheduling of the Final Phase of an Antidumping Investigation AGENCY: United States... United States is materially retarded, by reason of less-than-fair-value imports from Austria and/or China... preliminary determinations by the Department of Commerce that imports of xanthan gum from Austria and China...

  17. Investigation of inter-diffusion in bilayer GeTe/SnSe phase change memory films

    International Nuclear Information System (INIS)

    Devasia, Archana; MacMahon, David; Raoux, Simone; Campbell, Kristy A.; Kurinec, Santosh K.

    2012-01-01

    A metal-chalcogenide layer, SnSe, is inserted between the memory layer GeTe and the top electrode to form a phase change memory cell. The GeTe layer exhibits ovonic threshold switching at a threshold field of ∼ 110 V/μm. For subsequent implementation into applications and reliability, material inter-diffusion and sublimation are examined in bilayer phase change films of GeTe/SnSe. Transmission electron microscopy and parallel electron energy loss spectroscopy analyses reveal Sn migration to the GeTe layer, which is responsible for lowering the rhombohedral to cubic structural transformation temperature in GeTe. Incongruent sublimation of SnSe and GeTe is observed at temperatures higher than 500 °C. Severe volatilization of Se results in the separation of a metallic Sn phase. The use of Al 2 O 3 as a capping layer has been found to mitigate these effects. - Highlights: ► In the as-deposited state, GeTe is amorphous and SnSe is orthorhombic in structure. ► After 300 °C, Sn migration results in the formation of a Ge x Sn 1−x Te solid solution. ► Film decomposition and incongruent sublimation are observed at high temperatures. ► A consequence of incongruent sublimation is the separation of metallic Sn phase. ► Al2O3 capping mitigates volatilization and Sn phase separation at high temperatures.

  18. Low temperature thermodynamic investigation of the phase diagram of Sr3Ru2O7

    Science.gov (United States)

    Sun, D.; Rost, A. W.; Perry, R. S.; Mackenzie, A. P.; Brando, M.

    2018-03-01

    We studied the phase diagram of Sr3Ru2O7 by means of heat capacity and magnetocaloric effect measurements at temperatures as low as 0.06 K and fields up to 12 T. We confirm the presence of a new quantum critical point at 7.5 T which is characterized by a strong non-Fermi-liquid behavior of the electronic specific heat coefficient Δ C /T ˜-logT over more than a decade in temperature, placing strong constraints on theories of its criticality. In particular logarithmic corrections are found when the dimension d is equal to the dynamic critical exponent z , in contrast to the conclusion of a two-dimensional metamagnetic quantum critical end point, recently proposed. Moreover, we achieved a clear determination of the new second thermodynamic phase adjoining the first one at lower temperatures. Its thermodynamic features differ significantly from those of the dominant phase and characteristics expected of classical equilibrium phase transitions are not observed, indicating fundamental differences in the phase formation.

  19. Investigation of the imaging quality of synchrotron-based phase-contrast mammographic tomography

    International Nuclear Information System (INIS)

    Gureyev, T E; Mayo, S C; Nesterets, Ya I; Mohammadi, S; Menk, R H; Arfelli, F; Tromba, G; Lockie, D; Pavlov, K M; Kitchen, M J; Zanconati, F; Dullin, C

    2014-01-01

    We report the results of a systematic study of phase-contrast x-ray computed tomography in the propagation-based and analyser-based modes using specially designed phantoms and excised breast tissue samples. The study is aimed at the quantitative evaluation and subsequent optimization, with respect to detection of small tumours in breast tissue, of the effects of phase contrast and phase retrieval on key imaging parameters, such as spatial resolution, contrast-to-noise ratio, x-ray dose and a recently proposed ‘intrinsic quality’ characteristic which combines the image noise with the spatial resolution. We demonstrate that some of the methods evaluated in this work lead to substantial (more than 20-fold) improvement in the contrast-to-noise and intrinsic quality of the reconstructed tomographic images compared with conventional techniques, with the measured characteristics being in good agreement with the corresponding theoretical estimations. This improvement also corresponds to an approximately 400-fold reduction in the x-ray dose, compared with conventional absorption-based tomography, without a loss in the imaging quality. The results of this study confirm and quantify the significant potential benefits achievable in three-dimensional mammography using x-ray phase-contrast imaging and phase-retrieval techniques. (paper)

  20. Investigation of solid-phase hydrogenation of amino acids and peptides

    International Nuclear Information System (INIS)

    Zolotarev, Yu.A.; Myasoedov, N.F.; Zajtsev, D.A.; Lubnin, M.Yu.; Tatur, V.Yu.; Kozik, V.S.; Dorokhova, E.M.; Rozenberg, S.N.

    1990-01-01

    The possibility of synthesizing amino acids and peptides multiply labelled with tritium or deuterium by the method of solid-phase isotopic exchange with gaseous hydrogen isotopes was verified. Establishment of the isotopic hydrogen equilibrium between the gaseous phase and the solid phase formed by the amino acid molecules was found experimentally. The activation energy of the isotopic exchange is 13 kcal/mol. A mathematical model was set up for the isotopic exchange with a probable substitution of hydrogen atoms. Uniformly labelled amino acids were obtained in a high optical purity and with 80 to 90% hydrogen substitution by deuterium and tritium. Tritiated peptides were prepared in high yields at molar activities of 1.5 to 3.7 TBq/mmol. (author). 4 tabs

  1. Experimental investigation of two-phase flow patterns in minichannels at horizontal orientation

    Science.gov (United States)

    Saljoshi, P. S.; Autee, A. T.

    2017-09-01

    Two-phase flow is the simplest case of multiphase flow in which two phases are present for a pure component. The mini channel is considered as diameter below 3.0-0.2 mm and conventional channel is considered diameter above 3.0 mm. An experiment was conducted to study the adiabatic two-phase flow patterns in the circular test section with inner diameter of 1.1, 1.63, 2.0, 2.43 and 3.0 mm for horizontal orientation using air and water as a fluid. Different types of flow patterns found in the experiment. The parameters that affect most of these patterns and their transitions are channel size, phase superficial velocities (air and liquid) and surface tension. The superficial velocity of liquid and gas ranges from 0.01 to 66.70 and 0.01 to 3 m/s respectively. Two-phase flow pattern photos were recorded using a high speed CMOS camera. In this experiment different flow patterns were identified for different tube diameters that confirm the diameter effect on flow patterns in two-phase flows. Stratified flow was not observed for tube diameters less than 3.0 mm. Similarly, wavy-annular flow pattern was not observed in 1.6 and 1.0 mm diameter tubes due to the surface-tension effect and decrease in tube diameter. Buoyancy effects were clearly visible in 2.43 and 3.0 mm diameter tubes flow pattern. It has also observed that as the test-section diameter decreases the transition lines shift towards the higher gas and liquid velocity. However, the result of flow pattern lines in the present study has good agreement with the some of the existing flow patterns maps.

  2. A logistic dose-ranging method for phase I clinical investigations trials.

    Science.gov (United States)

    Murphy, J R; Hall, D L

    1997-11-01

    This paper describes an alternative to the continual reassessment method (CRM) for phase I trials. The logistic dose ranging strategy (LDRS) uses logistic regression and a dose allocation scheme similar to the CRM. It can easily be implemented from any logistic regression program. The LDRS can be a stand alone dose allocation scheme or it can be incorporated into standard three on a dose strategies to indicate when escalation can proceed more rapidly. Finally, the effect of covariates such as age or comorbid conditions on the toxicity expected for the dose selected for a phase II trial can be examined.

  3. Investigation of Portevin-Le Chatelier band with temporal phase analysis of speckle interferometry

    Science.gov (United States)

    Jiang, Zhenyu; Zhang, Qingchuan; Wu, Xiaoping

    2003-04-01

    A new method combining temporal phase analysis with dynamic digital speckle pattern interferometry is proposed to study Portevin-Le Chatelier effect quantitatively. The principle bases on that the phase difference of interference speckle patterns is a time-dependent function related to the object deformation. The interference speckle patterns of specimen are recorded with high sampling rate while PLC effect occurs, and the 2D displacement map of PLC band and its width are obtained by analyzing the displacement of specimen with proposed method.

  4. High-pressure Raman investigations of phase transformations in pentaerythritol (C(CH sub 2 OH) sub 4)

    CERN Document Server

    Bhattacharya, T

    2002-01-01

    Our high-pressure Raman scattering experiments on pentaerythritol (C(CH sub 2 OH) sub 4) show that this compound undergoes at least three phase transformations up to 25 GPa. Splitting of various modes at approx 6.3, approx 8.2 and 10 GPa suggests that these phase transformations result in lowering of crystalline symmetry. A very small discontinuous change in slope of most of the Raman-active modes is observed at 0.3 GPa. However, no other signature of a phase transition was observed at this pressure. The observed correlation of the pressures for the onset of the two phase transformations with the limiting values of the distances between various non-bonded atoms in the parent phase suggests that the molecular rearrangements across the phase transformations are not very drastic. In addition, our earlier Fourier transform infrared and present Raman investigations indicate that high-pressure compression leads to increase in strength of the hydrogen bond present in this compound.

  5. Investigation on the formation of a third phase in the extraction of Pu(IV) nitrate with tributyl phosphate

    International Nuclear Information System (INIS)

    Yu Enjiang; Liu Liming; Huang Huaian

    1986-01-01

    The formation of a third phase is studied in the system Pu(IV) nitratenitric acid-TBP-alkane diluent (or kerosine). The maximum concentration (solubility, S Pu ) of Pu(IV) in the equilibrium organic phase at which still no third phase is formed is measured as a function of the nitric acid concentration in the equilibrium aqueous phase C H , the temperature, and the molecular size of n-alkane duluent. Results show that maxima of S Pu at 6 to 7 M nitric acid are observed at 17 deg C, 26 deg C and 35 deg C while not at 40 deg C. Minima on the S Pu vs. C H curves at 0.5 to 2 M mitric acid have been observed at 17 deg C and 26 deg C. It is found that the molecular size of n-alkane diluents has a very pronounced effect on S Pu . The effect of aqueous equilibrium Pu(IV) concentration on the formation of a third phase is investigated, when the equilibrium HNO 3 concentration is 3.5 M. It is shown that the plutonium concentration of the third phase is increased with increasing aqueous equilibrium Pu(IV) concentration. The effect of the addition of lauryl alcohol on the S Pu is preliminarily studied

  6. M324 : investigation of closure pour elimination for phased construction of steel girder bridges.

    Science.gov (United States)

    2014-10-01

    Phased construction is a common practice used by State DOTs during the : replacement of a bridge. This method allows for the traffic flow to be maintained on half : of the bridge while a new deck is constructed on the other half. For steel girder bri...

  7. Investigating the Retention Mechanisms of Liquid Chromatography Using Solid-Phase Extraction Cartridges

    Science.gov (United States)

    O'Donnell, Mary E.; Musial, Beata A.; Bretz, Stacey Lowery; Danielson, Neil D.; Ca, Diep

    2009-01-01

    Liquid chromatography (LC) experiments for the undergraduate analytical laboratory course often illustrate the application of reversed-phase LC to solve a separation problem, but rarely compare LC retention mechanisms. In addition, a high-performance liquid chromatography instrument may be beyond what some small colleges can purchase. Solid-phase…

  8. Correlative theoretical and experimental investigation of the formation of AlYB14 and competing phases

    International Nuclear Information System (INIS)

    Hunold, Oliver; Chen, Yen-Ting; Music, Denis; Baben, Moritz to; Achenbach, Jan-Ole; Keuter, Philipp; Schneider, Jochen M.; Persson, Per O. Å.; Primetzhofer, Daniel

    2016-01-01

    The phase formation in the boron-rich section of the Al-Y-B system has been explored by a correlative theoretical and experimental research approach. The structure of coatings deposited via high power pulsed magnetron sputtering from a compound target was studied using elastic recoil detection analysis, electron energy loss spectroscopy spectrum imaging, as well as X-ray and electron diffraction data. The formation of AlYB 14 together with the (Y,Al)B 6 impurity phase, containing 1.8 at. % less B than AlYB 14 , was observed at a growth temperature of 800 °C and hence 600 °C below the bulk synthesis temperature. Based on quantum mechanical calculations, we infer that minute compositional variations within the film may be responsible for the formation of both icosahedrally bonded AlYB 14 and cubic (Y,Al)B 6 phases. These findings are relevant for synthesis attempts of all boron rich icosahedrally bonded compounds with the space group: Imma that form ternary phases at similar compositions.

  9. Final Report: Investigations of Mixed-Phase Cloud Microphysical, Radiative, and Dynamical Processes

    Energy Technology Data Exchange (ETDEWEB)

    Shupe, Matthew [Univ. of Colorado, Boulder, CO (United States)

    2016-08-18

    This project supported the principle investigator’s work on a number of studies regarding mixed-phase clouds and in various related collaborations with ARM and related scientists. This project has contributed to numerous publications and conference/meeting presentations.

  10. Investigation on Capacitor Switching Transient Limiter with a Three phase Variable Resistance

    DEFF Research Database (Denmark)

    Naderi, Seyed Behzad; Jafari, Mehdi; Zandnia, Amir

    2017-01-01

    In this paper, a capacitor switching transient limiter based on a three phase variable resistance is proposed. The proposed structure eliminates the capacitor switching transient current and over-voltage by introducing a variable resistance to the current path with its special switching pattern. ...

  11. Model investigations 3D of gas-powder two phase flow in descending bed with consideration radial distribution of flow

    Directory of Open Access Journals (Sweden)

    B. Panic

    2013-04-01

    Full Text Available The results of experimental investigations concerning radial distribution of powder accumulation in bed and static pressure were presented in this paper. To realize this research physical model of gas-powder two phase flow with descending bed was projected and constructed. Amounts of “dynamic” and “static” powder accumulated in bed, in dependence on gas velocity and of bed particles were investigated. In 3D model “static” powder (with its radial distribution at the tuyere level and in the higher part of bed was measured. The influence of bed particles, powder and gas radial distribution on values of interaction forces between flow phases in investigated system was defined.

  12. Investigation of Regularities of Heat and Mass Transfer and Phase Transitions during Water Droplets Motion through High-Temperature Gases

    Directory of Open Access Journals (Sweden)

    Roman S. Volkov

    2014-06-01

    Full Text Available The macroscopic regularities of heat and mass transfer and phase transitions during water droplets motion through high-temperature (more than 1000 K gases have been investigated numerically and experimentally. Water droplet evaporation rates have been established. Gas and water vapors concentrations and also temperature values of gas-vapor mixture in small neighborhood and water droplet trace have been singled out. Possible mechanisms of droplet coagulation in high-temperature gas area have been determined. Experiments have been carried out with the optical methods of two-phase gas-vapor-droplet mixtures diagnostics (“Particle Image Velocimetry” and “Interferometric Particle Imaging” usage to assess the adequateness of developed heat and mass transfer models and the results of numerical investigations. The good agreement of numerical and experimental investigation results due to integral characteristics of water droplet evaporation has been received.

  13. Phase equilibria and structural investigations in the system Al–Fe–Si

    Science.gov (United States)

    Marker, Martin C.J.; Skolyszewska-Kühberger, Barbara; Effenberger, Herta S.; Schmetterer, Clemens; Richter, Klaus W.

    2011-01-01

    The Al–Fe–Si system was studied for an isothermal section at 800 °C in the Al-rich part and at 900 °C in the Fe-rich part, and for half a dozen vertical sections at 27, 35, 40, 50 and 60 at.% Fe and 5 at.% Al. Optical microscopy and powder X-ray diffraction (XRD) was used for initial sample characterization, and Electron Probe Microanalysis (EPMA) and Scanning Electron Microscopy (SEM) of the annealed samples was used to determine the exact phase compositions. Thermal reactions were studied by Differential Thermal Analysis (DTA). Our experimental results are generally in good agreement with the most recent phase diagram versions of the system Al–Fe–Si. A new ternary high-temperature phase τ12 (cF96, NiTi2-type) with the composition Al48Fe36Si16 was discovered and was structurally characterized by means of single-crystal and powder XRD. The variation of the lattice parameters of the triclinic phase τ1 with the composition Al2+xFe3Si3−x (−0.3 < x < 1.3) was studied in detail. For the binary phase FeSi2 only small solubility of Al was found in the low-temperature modification LT-FeSi2 (ζβ) but significant solubility in the high-temperature modification HT-FeSi2 (ζα) (8.5 at.% Al). It was found that the high-temperature modification of FeSi2 is stabilized down to much lower temperature in the ternary, confirming earlier literature suggestions on this issue. DTA results in four selected vertical sections were compared with calculated sections based on a recent CALPHAD assessment. The deviations of liquidus values are significant suggesting the need for improvement of the thermodynamic models. PMID:27087751

  14. An experimental investigation of stratified two-phase pipe flow at small inclinations

    Energy Technology Data Exchange (ETDEWEB)

    Espedal, Mikal

    1998-12-31

    The prediction of stratified flow is important for several industrial applications. Stratified flow experiments were carefully performed in order to investigate the performance of a typical model which uses wall friction factors based on single phase pipe flow as described above. The test facility has a 18.5 m long and 60 mm i.d. (L/D=300) acrylic test section which can be inclined between -10 {sup o} and +10 {sup o}. The liquid holdup was measured by using fast closing valves and the pressure gradients by using three differential pressure transducers. Interfacial waves were measured by thin wire conductance probes mounted in a plane perpendicular to the main flow. The experiments were performed using water and air at atmospheric pressure. The selected test section inclinations were between -3 {sup o} and +0.5 {sup o} to the horizontal plane. A large number of experiments were performed for different combinations of air and water flow rates and the rates were limited to avoid slug flow and stratified flow with liquid droplets. The pressure gradient and the liquid holdup were measured. In addition the wave probes were used to find the wave heights and the wave power spectra. The results show that the predicted pressure gradient using the standard models is approximately 30% lower than the measured value when large amplitude waves are present. When the flow is driven by the interfacial force the test section inclination has minor influence on the deviation between predicted and measured pressure gradients. Similar trends are apparent in data from the literature, although they seem to have gone unnoticed. For several data sets large spread in the predictions are observed when the model described above was used. Gas wall shear stress experiments indicate that the main cause of the deviation between measured and predicted pressure gradient and holdup resides in the modelling of the liquid wall friction term. Measurements of the liquid wall shear stress distribution

  15. Investigation of the effect of tube voltage and imaging geometry on phase contrast imaging for a micro-CT system

    International Nuclear Information System (INIS)

    Gui Jianbao; Zou Jing; Rong Junyan; Hu Zhanli; Zhang Qiyang; Zheng Hairong; Xia Dan

    2012-01-01

    Based upon a bench-top micro-CT system, propagation-based phase-contrast imaging has been investigated using insects and a thin plastic sheet. The system mainly includes a micro-focus source with focal spot size of 13-20 μm and a cooled X-ray CCD detector with pixel size of 24 μm. The edge-enhancement effect can be found clearly in the acquired images. With a 0.5 mm thickness plastic edge phantom, the effects of X-ray tube voltage and imaging geometry on the phase-contrast imaging were investigated, and quantitative index, edge-enhancement index (EEI), were also calculated. In our study, an interesting phenomenon was observed that the phase-contrast effect becomes more pronounced as the tube voltage increases from 20 kVp to 90 kVp. Further investigation indicates that smaller focal spot size resulting from the reduction of tube current at higher tube voltage, has caused the unexpected phenomenon. Inferred from our results, phase-contrast effect is insensitive to the tube voltage in the range of 20-90 kVp (widely used in medical diagnosis); however, it is sensitive to the focal spot size. In addition, for the investigation of the effect of imaging geometry, an optimal geometric magnification range of 2.5-4.5 is suggested to get a good phase-contrast imaging for a micro-CT system with source-to-detector distance of 720 mm.

  16. Investigation of shape memory of red blood cells using optical tweezers and quantitative phase microscopy

    Science.gov (United States)

    Cardenas, Nelson; Mohanty, Samarendra K.

    2012-03-01

    RBC has been shown to possess shape memory subsequent to shear-induced shape transformation. However, this property of RBC may not be generalized to all kinds of stresses. Here, we report our observation on the action of radiation pressure forces on RBC's shape memory using optical manipulation and quantitative phase microscopy (OMQPM). QPM, based on Mach-Zehnder interferrometry, allowed measurement of dynamic changes of shape of RBC in optical tweezers at different trapping laser powers. In high power near-infrared optical tweezers (>200mW), the RBC was found to deform significantly due to optical forces. Upon removal of the tweezers, hysteresis in recovering its original resting shape was observed. In very high power tweezers or long-term stretching events, shape memory was almost erased. This irreversibility of the deformation may be due to temperature rise or stress-induced phase transformation of lipids in RBC membrane.

  17. Two-Phase Flow Simulations for PTS Investigation by Means of Neptune_CFD Code

    Directory of Open Access Journals (Sweden)

    Maria Cristina Galassi

    2009-01-01

    Full Text Available Two-dimensional axisymmetric simulations of pressurized thermal shock (PTS phenomena through Neptune_CFD module are presented aiming at two-phase models validation against experimental data. Because of PTS complexity, only some thermal-hydraulic aspects were considered. Two different flow configurations were studied, occurring when emergency core cooling (ECC water is injected in an uncovered cold leg of a pressurized water reactor (PWR—a plunging water jet entering a free surface, and a stratified steam-water flow. Some standard and new implemented models were tested: modified turbulent - models with turbulence production induced by interfacial friction, models for the drag coefficient, and interfacial heat transfer models. Quite good agreement with experimental data was achieved with best performing models for both test cases, even if a further improvement in phase change modelling would be suitable for nuclear technology applications.

  18. Investigation on the role of nitrogen in crystallization of Sb-rich phase change materials

    International Nuclear Information System (INIS)

    Choi, Jihoon; Lee, Taek Sung; Lee, Suyoun; Kim, Won Mok; Cheong, Byung-ki; Lee, Hyun Seok; Kim, Donghwan

    2009-01-01

    To better understand the role of nitrogen (N) during crystallization of Sb-rich phase change materials, a study was conducted using Sb and Sb 70 Te 30 as host materials of N. Crystallization of the as-sputtered Sb-N films of varying N content was examined to reveal that Sb-N bonds are formed in the as-sputtered states, enhancing amorphous phase stability increasingly with N content. Crystallization appeared to proceed with irreversible dissociation of these bonds to form N 2 molecules that may then exist stably during the subsequent memory operations. N 2 molecules are considered to play as growth-retarding agents as demonstrated with memory operations of N-doped Sb 70 Te 30 .

  19. Three-dimensional investigation of the two-phase flow structure in a bubbly pipe flow

    International Nuclear Information System (INIS)

    Schmidl, W.; Hassan, Y.A.; Ortiz-Villafuerte, J.

    1996-01-01

    Particle image velocimetry (PIV) is a nonintrusive measurement technique that can be used to study the structure of various fluid flows. PIV is used to measure the time-varying, full-field velocity data of a particle-seeded flow field within either a two-dimensional plane or three-dimensional volume. PIV is a very efficient measurement technique since it can obtain both qualitative and quantitative spatial information about the flow field being studied. The quantitative spatial velocity information can be further processed into information of flow parameters such as vorticity and turbulence over extended areas. The objective of this study was to apply recent advances and improvements in the PIV flow measurement technique to the full-field, nonintrusive analysis of a three-dimensional, two-phase fluid flow system in such a manner that both components of the two-phase system could be experimentally quantified

  20. Investigation of Effect Additive Phase Change Materials on the Thermal Conductivity

    Science.gov (United States)

    Nakielska, Magdalena; Chalamoński, Mariusz; Pawłowski, Krzysztof

    2017-10-01

    The aim of worldwide policy is to reduce the amount of consumed energy and conventional fuels. An important branch of the economy that affects the energy balance of the country is construction industry. In Poland, since January 1st, 2017 new limit values have been valid regarding energy saving and thermal insulation of buildings. To meet the requirements of more and more stringent technical and environmental standards, new technological solutions are currently being looked for. When it comes to the use of new materials, phase-change materials are being widely introduced into construction industry. Thanks to phase-change materials, we can increase the amount of heat storage. Great thermal inertia of the building provides more stable conditions inside the rooms and allows the use of unconventional sources of energy such as solar energy. A way to reduce the energy consumption of the object is the use of modern solutions for ventilation systems. An example is the solar chimney, which supports natural ventilation in order to improve internal comfort of the rooms. Numerous studies are being carried out in order to determine the optimal construction of solar chimneys in terms of materials and construction parameters. One of the elements of solar chimneys is an absorption plate, which affects the amount of accumulated heat in the construction. In order to carry out the research on the thermal capacity of the absorption plate, the first research work has been already planned. The work presents the research results of a heat-transfer coefficient of the absorption plates samples made of cement, aggregate, water, and phase-change material in different volume percentage. The work also presents methodology and the research process of phase-change material samples.

  1. R-Phase Phenomena in Neutron Diffraction Investigations of Thermomechanically Loaded NiTi Polycrystals

    Czech Academy of Sciences Publication Activity Database

    Lukáš, Petr; Šittner, Petr; Neov, Dimitar; Novák, Václav; Lugovyy, Dmytro; Tovar, M.

    404/407, - (2002), s. 835-840 ISSN 0255-5476. [Proceedings of the European Conference on Residual Stresses /6./. Coimbra, 10.07.2000-12.07.2000] R&D Projects: GA ČR GV202/97/K038; GA AV ČR IAA1048107 Keywords : shape memory alloy * neutron diffraction * martensitic transformation * NiTi * R-phase Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 0.613, year: 2002

  2. A facility for the experimental investigation of single substance two phase flow

    International Nuclear Information System (INIS)

    Maeder, P.F.; Dickinson, D.A.; Nikitopoulos, D.E.; DiPippo, R.

    1985-01-01

    The paper describes a research facility dedicated to single-substance two-phase flow. The working fluid is dichlorotetrafluoroethane (or refrigerant R-114), allowing both operation at manageable pressures, temperatures and flowrates, and application of results to practical situations through similarity. Operation is in the blowdown mode. The control and data acquisition systems are fully automated and computer controlled. A range of flow conditions from predominantly liquid flow to high velocity, high void fraction choked flow can be attained

  3. Investigation of a phase transition in a single optically levitated microdroplet by Raman-Mie scattering.

    Science.gov (United States)

    Trunk, M; Lübben, J F; Popp, J; Schrader, B; Kiefer, W

    1997-05-20

    Light-scattering measurements of optically levitated microdroplets containing three components, glycerin, water, and ammonium sulfate, are presented. Evaporation of the microdroplet is studied by means of morphology-dependent resonances observed in both Raman spectra as well as elastically scattered light and by the simultaneous measurement of the laser power. The phase transition from the liquid to the solid state of ammonium sulfate inside the microdroplet is observed by means of morphology-dependent resonances and Raman scattering.

  4. Experimental investigation on local parameter measurement using optical probes in two-phase flow under rolling condition

    International Nuclear Information System (INIS)

    Tian Daogui; Sun Licheng; Yan Changqi; Liu Guoqiang

    2013-01-01

    In order to get more local interfacial information as well as to further comprehend the intrinsic mechanism of two-phase flow under rolling condition, a method was proposed to measure the local parameters by using optical probes under rolling condition in this paper. An experimental investigation of two-phase flow under rolling condition was conducted using the probe fabricated by the authors. It is verified that the probe method is feasible to measure the local parameters in two'-phase flow under rolling condition. The results show that the interfacial parameters distribution near wall region has a distinct periodicity due to the rolling motion. The averaged deviation of the void fraction measured by the probe from that obtained from measured pressure drop is about 8%. (authors)

  5. Investigation of fringing electric field effect on high-resolution blue phase liquid crystal spatial light modulator.

    Science.gov (United States)

    Yan, Jing; Guo, Zhengbo; Xing, Yufei; Li, Qing

    2015-08-20

    The fringing electric field effect which determines the performance of a high-resolution blue phase liquid crystal spatial light modulator (BPLC-SLM) is investigated by numerical modeling. The BPLC-SLM is polarization-dependent due to the transverse electric field component. The physical mechanism of the phase profile properties for different polarization states is analyzed. General design issues related to the BPLC-SLM configuration and phase profile properties are discussed. Notably, the material parameters and cell gap thickness are both optimized to obtain a low operation voltage (V2π=26.07  V). This work provides fundamental understanding for the feasibility of low operation voltage and high spatial resolution BPLC-SLM.

  6. Phase diagram, thermodynamic investigations, and modelling of systems relevant to lithium-ion batteries

    Energy Technology Data Exchange (ETDEWEB)

    Fuertauer, Siegfried; Beutl, Alexander; Flanorfer, Hans [Vienna Univ. (Austria). Dept. of Inorganic Chemistry - Functional Materials; Li, Dajian; Cupid, Damian [Karlsruhe Institute of Technology (KIT), Eggenstein-Leopoldshafen (Germany). Inst. for Applied Materials - Applied Materials Physics (IAM-AWP); Henriques, David; Giel, Hans; Markus, Thorsten [Mannheim Univ. of Applied Sciences (Germany). Inst. for Thermo- and Fluiddynamics

    2017-11-15

    This article reports on two consecutive joint projects titled ''Experimental Thermodynamics and Phase Relations of New Electrode Materials for Lithium-Ion Batteries'', which were performed in the framework of the WenDeLIB 1473 priority program ''Materials with new Design for Lithium Ion Batteries''. Hundreds of samples were synthesized using experimental techniques specifically developed to deal with highly reactive lithium and lithium-containing compounds to generate electrochemical, phase diagram and crystal structure data in the Cu-Li, Li-Sn, Li-Sb, Cu-Li-Sn, Cu-Li-Sb and selected oxide systems. The thermochemical and phase diagram data were subsequently used to develop self-consistent thermodynamic descriptions of several binary systems. In the present contribution, the experimental techniques, working procedures, results and their relevance to the development of new electrode materials for lithium ion batteries are discussed and summarized. The collaboration between the three groups has resulted in more than fifteen (15) published articles during the six-year funding period.

  7. Numerical Investigation on the Effects of a Precursor Wetting Film on the Displacement of Two Immiscible Phases Along a Channel

    KAUST Repository

    Bao, Kai

    2015-10-08

    A set of numerical experiments has been conducted to study the effect of a precursor fluid layer on the motion of two phase system in a channel. This system is characterized by coupled Cahn-Hillard and Navier-Stokes system together with slip boundary conditions. The solution of the governing equation involves first the solution of Cahn-Hillard equation with semi-implicit and Mixed finite element discritization with a convex splitting scheme. The Navier-Stokes equations are then solved with a P2-P0 mixed finite element method. Three cases have been investigated; in the first the effect of different wettability scenarios with no precursor layer has been investigated. In the second scenario, the effect of the precursor layer for different wettability conditions is investigated. In the third case, the effect of the thickness of the precursor layer is investigated. It is found that, wettability conditions have considerable effect on the flow of the considered two-phase system. Furthermore the existence of the precursor layer has additional influence on the breakthrough of the phases.

  8. Investigation of an unusual low-temperature phase transformation in RbBH4 by neutron diffraction

    International Nuclear Information System (INIS)

    Kitchen, Brian B.; Verdal, Nina; Udovic, Terrence J.; Rush, John J.; Hartman, Michael R.; DeVries, Daniel J.

    2013-01-01

    To investigate the previously reported low-temperature phase transition in rubidium borohydride (RbBH 4 ) near 48.5 K, we carried out neutron powder diffraction and vibrational spectroscopy measurements both above and below this temperature on an isotopically-enriched sample of Rb 11 BD 4 . Our diffraction data reflected an average cubic Fm3 ¯ m structure with BD 4 − anion orientational disorder at all temperatures, with no hint of extra Bragg peaks due to long-range orientational order below the transition temperature as reported by others. These structural results and careful analysis of torsional vibrations in RbBD 4 corroborate the results of prior neutron vibrational spectroscopy measurements suggesting that the low-temperature RbBH 4 structure indeed possesses some orientational ordering of the BH 4 − anions, but of a shorter-ranged nature insensitive to powder diffraction methods. - The neutron powder diffraction pattern of RbBD 4 below the phase transition temperature (shown here in black) is indistinguishable from that collected above the phase transition temperature. The inset depicts the cubic structure that fits the data at both temperatures. - Highlights: • We investigated the nature of the RbBD 4 phase transition using NVS and NPD. • A change in shape of the RbBD 4 torsion mode was observed across the transition. • The RbBD 4 diffraction pattern across this phase transition was unchanged. • The phase transition in RbBD 4 appears to produce only short-range ordering of BD 4 −

  9. In situ TEM investigation on the precipitation behavior of μ phase in Ni-base single crystal superalloys

    International Nuclear Information System (INIS)

    Gao, Shuang; Liu, Zhi-Quan; Li, Cai-Fu; Zhou, Yizhou; Jin, Tao

    2016-01-01

    The precipitation behavior of μ phase in Ni-base single crystal superalloys was investigated by in situ transmission electron microscopy (TEM). A layer-by-layer growth process with a ledge propagation mechanism was first observed during in situ precipitation. Three types of μ phase with different morphologies were found, which grow along [001] μ with (001) μ planar defects, [-111] μ with (1–12) μ planar defects, as well as both directions with mixed planar defects. High-resolution TEM image and established atomic models reveal a basic growth mechanism of μ phase by stacking on (001) μ plane and randomly forming coherent planar defects, while the nucleation of incoherent (1–12) μ planar defects at the early stage of precipitation plays an important role in affecting the basic growth mechanism. The frequent faults during the stacking process of the sub-unit layers within μ lattice should be responsible for the defect formation. -- Graphical abstract: In situ transmission electron microscopy (TEM) investigations reveal the layer-by-layer growth mechanism of μ phase precipitated in Ni-base single crystal superalloys. Three types of μ phase with different morphologies were formed at 1050 °C, which grows along [001] μ with (001) μ planar defects, [-111] μ with (1–12) μ planar defects, as well as both directions with mixed planar defects respectively. Formation of (001) μ micro-twin and stacking fault is the essential feature for precipitated μ phase, while nucleation of incoherent (1–12) μ planar defects plays an important role in changing growth method. Display Omitted

  10. Katoite under pressure: an ab initio investigation of its structural, elastic and vibrational properties sheds light on the phase transition.

    Science.gov (United States)

    Erba, Alessandro; Navarrete-López, Alejandra M; Lacivita, Valentina; D'Arco, Philippe; Zicovich-Wilson, Claudio M

    2015-01-28

    The evolution under pressures up to 65 GPa of structural, elastic and vibrational properties of the katoite hydrogarnet, Ca3Al2(OH)12, is investigated with an ab initio simulation performed at the B3LYP level of theory, by using all-electron basis sets with the Crystal periodic program. The high-symmetry Ia3d phase of katoite, stable under ambient conditions, is shown to be destabilized, as pressure increases, by interactions involving hydrogen atoms and their neighbors which weaken the hydrogen bonding network of the structure. The corresponding thermodynamical instability is revealed by anomalous deviations from regularity of its elastic constants and by numerous imaginary phonon frequencies, up to 50 GPa. Interestingly, as pressure is further increased above 50 GPa, the Ia3d structure is shown to become stable again (all positive phonon frequencies and regular elastic constants). However, present calculations suggest that, above about 15 GPa and up to at least 65 GPa, a phase of I4[combining macron]3d symmetry (a non-centrosymmetric subgroup of Ia3d) becomes more stable than the Ia3d one, being characterized by strengthened hydrogen bonds. At low-pressures (between about 5 GPa and 15 GPa), both phases show some instabilities (more so for I4[combining macron]3d than for Ia3d), thus suggesting either the existence of a third phase or a possible phase transition of second order.

  11. Investigation of the void coefficient and other integral parameters in the PROTEUS-LWHCR phase II program

    International Nuclear Information System (INIS)

    Seiler, R.; Chawla, R.; Gmur, K.; Hager, H.; Berger, H.D.; Bohme, R.

    1988-01-01

    Comparisons of calculated and measured neutron balance components are reported for the 7.5% fissile plutonium reference test lattice of the PROTEUS-light water high conversion reactor (LWHCR) phase II program, both wet (with H/sub 2/O) and dry (100% void). Special experimental techniques have been developed and applied, particularly for κ/sub ∞/, and the range of directly measured reaction rate ratios has been extended. For the two cell codes tested, WIMS-D/1981 library and KARBUS/KEDAK-4, specific shortcomings have been identified; the new measurements have been found to be significantly more representative and accurate than the earlier phase I experiments. The κ/sub ∞/ void coefficient for the phase II reference lattice between 0 and 100% void has been found to be qualitatively different from those assessed for the earlier phase I test lattices. Consideration of the individual void coefficient components show this to be largely a consequence of the more LWHCR-representative fuel rod diameter and plutonium isotopic composition of the fuel currently being used. Results of control rod studies conducted for the phase II reference lattice - both wet and dry - serve to illustrate the efforts being made toward investigations of special power reactor features

  12. Investigating the heat transfer on the top side of inclined printed circuit boards during vapour phase soldering

    International Nuclear Information System (INIS)

    Illés, Balázs; Géczy, Attila

    2016-01-01

    Highlights: • Investigating the effect of inclination on heat transfer uniformity and intensity during VPS. • Even moderate inclination has high impact on the condensate layer and on the heat transfer. • Inclination under 1° has negative effect on temperature distribution of the soldered board. • Inclination from 1° to 10° improves heat transfer uniformity of vapour phase soldering. • Inclination can help to reduce soldering failures during vapour phase soldering. - Abstract: In this paper, heat transfer and condensate layer formation was investigated by numerical simulations on the top side of inclined printed circuit boards during vapour phase soldering. The phase change on the inclined surface and the transfer mechanisms in the condensate layer were embedded in a three-dimensional model. Steady-state and saturated vapour conditions were applied as boundary conditions in order to study the pure effect of the inclination. Due to the electronic component and circuit board structures during soldering only moderate inclination angles were studied between 0° and 10°. It was found that a moderate inclination of the printed circuit board has considerable effects on the formation of condensate layer and consequently on heat transfer. Compared to the default horizontal orientation of the board, the thickness differences of the condensate layer can be decreased with an optimised inclination of the printed circuit board. This effect homogenizes heat transfer during the process, enabling improved solder joint quality, with reduced overall soldering failure count.

  13. Aespoe hard rock laboratory. Field investigation methodology and instruments used in the preinvestigation phase, 1986-1990

    International Nuclear Information System (INIS)

    Almen, K.E.; Zellman, O.

    1991-12-01

    The Aespoe hard rock laboratory project started in 1986. The pre-investigation phase, 1986-1990, involved extensive field measurements from the surface as well as from boreholes, aimed at characterizing the rock formation with regard to geology, geohydrology, hydrochemistry and rock mechanics. The field investigation methodology used in the project was based on experience from and developments during the previous SKB study site investigation programme. However, in some respects the techniques were changed or modified. Major changes have been possible due to a new drilling technique, telescope-type drilling. This report describes the logistics of the investigation programme, characterized to a large extent by multi-purpose planning and performance of the activities in order to optimize the use of available resources; time, personnel and equipment. Preliminary hydraulic testing and groundwater sampling were conducted during the drilling of each borehole. When the drilling was completed an extensive set of singlehole investigations were carried out: geophysical logging, borehole radar, hydraulic tests of different kinds, water sampling and rock stress measurements. Multipackers were installed in the boreholes as soon as possible after the borehole investigations. The system enables monitoring of groundwater pressure, water sampling and groundwater flow measurements to be performed by means of dilution tests and tracer injection. Boreholes with such equipment were used as observation holes during interference pumping tests and long term hydraulic and tracer tests. The monitoring programme will continue during the subsequent phases of construction and operation of the Aespoe hard rock laboratory. (83 refs., 94 figs.) (au)

  14. Pulse Phase Dynamic Thermal Tomography Investigation on the Defects of the Solid-Propellant Missile Engine Cladding Layer

    Science.gov (United States)

    Peng, Wei; Wang, Fei; Liu, Jun-yan; Xiao, Peng; Wang, Yang; Dai, Jing-min

    2018-04-01

    Pulse phase dynamic thermal tomography (PP-DTT) was introduced as a nondestructive inspection technique to detect the defects of the solid-propellant missile engine cladding layer. One-dimensional thermal wave mathematical model stimulated by pulse signal was developed and employed to investigate the thermal wave transmission characteristics. The pulse phase algorithm was used to extract the thermal wave characteristic of thermal radiation. Depth calibration curve was obtained by fuzzy c-means algorithm. Moreover, PP-DTT, a depth-resolved photothermal imaging modality, was employed to enable three-dimensional (3D) visualization of cladding layer defects. The comparison experiment between PP-DTT and classical dynamic thermal tomography was investigated. The results showed that PP-DTT can reconstruct the 3D topography of defects in a high quality.

  15. 1-D Two-phase Flow Investigation for External Reactor Vessel Cooling

    International Nuclear Information System (INIS)

    Kim, Jae Cheol

    2007-02-01

    During a severe accident, when a molten corium is relocated in a reactor vessel lower head, the RCF(Reactor Cavity Flooding) system for ERVC (External Reactor Vessel Cooling) is actuated and coolants are supplied into a reactor cavity to remove a decay heat from the molten corium. This severe accident mitigation strategy for maintaining a integrity of reactor vessel was adopted in the nuclear power plants of APR1400, AP600, and AP1000. Under the ERVC condition, the upward two-phase flow is driven by the amount of the decay heat from the molten corium. To achieve the ERVC strategy, the two-phase natural circulation in the annular gap between the external reactor vessel and the insulation should be formed sufficiently by designing the coolant inlet/outlet area and gap size adequately on the insulation device. Also the natural circulation flow restriction has to be minimized. In this reason, it is needed to review the fundamental structure of insulation. In the existing power plants, the insulation design is aimed at minimizing heat losses under a normal operation. Under the ERVC condition, however, the ability to form the two-phase natural circulation is uncertain. Namely, some important factors, such as the coolant inlet/outlet areas, flow restriction, and steam vent etc. in the flow channel, should be considered for ERVC design. T-HEMES 1D study is launched to estimate the natural circulation flow under the ERVC condition of APR1400. The experimental facility is one-dimensional and scaled down as the half height and 1/238 channel area of the APR1400 reactor vessel. The air injection method was used to simulate the boiling at the external reactor vessel and generate the natural circulation two-phase flow. From the experimental results, the natural circulation flow rate highly depended on inlet/outlet areas and the circulation flow rate increased as the outlet height as well as the supplied water head increased. On the other hand, the simple analysis using the drift

  16. Experimental investigation of two-stage thermoelectric generator system integrated with phase change materials

    DEFF Research Database (Denmark)

    Ahmadi Atouei, Saeed; Ranjbar, Ali Akbar; Rezaniakolaei, Alireza

    2017-01-01

    experimentally. In the first stage, a TEG module installed between a phase change material (PCM) heat sink, as cooling system, and an electrical heater, as the heat source. Because of the inherent characteristics of PCMs to save the thermal energy as latent heat, the PCM heat sink is used as the heat source...... of the second stage TEGs. In the second stage, five smaller TEG modules are installed around the PCM with individual heat sinks for cooling with natural convection. In order to have a comparison between a common TEG system and the proposed two-stage TEG system, a one-stage thermoelectric generator with forced...

  17. Investigation of metal-matrix composite containing liquid-phase dispersion

    Czech Academy of Sciences Publication Activity Database

    Strunz, Pavel; Mukherji, D.; Gilles, R.; Geue, T.; Rösler, J.

    2012-01-01

    Roč. 340, 012098 (2012), s. 1-15 ISSN 1742-6588. [5th European Conference on Neutron Scattering. Praha, 17.07.2011-21.07.2011] R&D Projects: GA MPO FR-TI1/378 Grant - others:European Commission(XE) RII3-CT-2003-505925 Program:FP6 Institutional support: RVO:61389005 Keywords : metal-matrix composite * liquid- phase dispersion * strengthening * neutron diffraction Subject RIV: BM - Solid Matter Physics ; Magnetism http://iopscience.iop.org/1742-6596/340/1/012098

  18. Experimental Investigation of Thermal Conductivity of Concrete Containing Micro-Encapsulated Phase Change Materials

    DEFF Research Database (Denmark)

    Pomianowski, Michal Zbigniew; Heiselberg, Per; Jensen, Rasmus Lund

    2011-01-01

    in this article utilizes integration of the concrete and the microencapsulated Phase Change Material (PCM). PCM has the ability to absorb and release significant amounts of heat at a specific temperature range. As a consequence of admixing PCM to the concrete, new thermal properties like thermal conductivity...... and specific heat capacity have to be defined. This paper presents results from the measurements of the thermal conductivity of various microencapsulated PCM-concrete and PCM-cement-paste mixes. It was discovered that increase of the amount of PCM decreases the thermal conductivity of the concrete PCM mixture...

  19. Applications of the phase function method ideas for the investigation of the two- and three-body system properties

    International Nuclear Information System (INIS)

    Petrov, N.M.; Pushkash, A.M.

    1985-01-01

    In accordance with the main idea of the phase function method the two-body off-shell scattering amplitudes are considered as the limit of the scattering amplitude sequence corresponding to the sequence of the R-radius cut-off potentials. The explicit analytical expression for the scattering amplitudes function is obtained in the case of separable potentials, due to which the three-body problem is investigated

  20. An investigation of long-distance propagation of gravity waves under CAWSES India Phase II Programme

    Directory of Open Access Journals (Sweden)

    N. Parihar

    2015-05-01

    Full Text Available Coordinated measurements of airglow features from the mesosphere–lower thermosphere (MLT region were performed at Allahabad (25.5° N, 81.9° E and Gadanki (13.5° N, 79.2° E, India to study the propagation of gravity waves in 13–27° N latitude range during the period June 2009 to May 2010 under CAWSES (Climate And Weather of Sun Earth System India Phase II Programme. At Allahabad, imaging observations of OH broadband emissions and OI 557.7 nm emission were made using an all-sky imager, while at Gadanki photometric measurements of OH (6, 2 Meinel band and O2 (0, 1 Atmospheric band emissions were carried out. On many occasions, the nightly observations reveal the presence of similar waves at both locations. Typically, the period of observed similar waves lay in the 2.2–4.5 h range, had large phase speeds (~ 77–331 m s−1 and large wavelengths (~ 1194–2746 km. The images of outgoing long-wave radiation activity of the National Oceanic and Atmospheric Administration (NOAA and the high-resolution infrared images of KALPANA-1 satellite suggest that such waves possibly originated from some nearby convective sources. An analysis of their propagation characteristics in conjunction with SABER/TIMED temperature profiles and Horizontal Wind Model (HWM 2007 wind estimates suggest that the waves propagated over long distances (~ 1200–2000 km in atmospheric ducts.

  1. Investigation of the kinetics and microscopic mechanism of solid-solid phase transitions in HMX

    Science.gov (United States)

    Bowlan, Pamela; Suvorova, Natalya; Oschwald, Dave; Bowlan, John; Rector, Kirk; Henson, Bryan; Smilowitz, Laura

    2017-06-01

    Although studied intensely in the 2000's, a number of important questions about solid-solid phase transitions in the energetic organic material octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) remain. The mechanism by which one of the four isomorphs, known as δ, γ, α and β, transforms into another, and the conditions (i.e. temperature and pressure) and rates at which these transitions take place are still not fully known, yet important for predicting and controlling energy release phenomena in HMX such as detonation. The theory of virtual melting, by which a liquid forms at the interface of a nucleation site, is necessary to explain transformations between certain of the four different phases of HMX, such as the β to δ transition. However the existence of this disordered intermediate state has never been directly proven due to the need for both spatial (HMX using X-ray diffraction and confocal Raman and near-field infrared microscopy.

  2. Investigation of the liquid crystalline phase transitions using the new modified Pople Karasz model

    Science.gov (United States)

    Yazıcı, Mustafa; Özgan, Şükrü; Keskin, Mustafa

    2005-09-01

    Thermodynamics of solid nematic and nematic isotropic liquid transitions are studied by using a new modified model that combines the modified theories of Chandrasekhar et al. with those Keskin and Özgan which are based on the Pople Karasz theory. The thermodynamic properties of the disordered system are evaluated relative to those of the perfectly ordered one within the lowest approximation of the cluster variation method which is identical to the mean-field approximation. The results are compared with the some available experimental data, the predictions of the original Pople Karasz (PK) theory and its previous modified theories. For nematic isotropic and s(nematic) at the transition temperatures, the agreement is very good and much better than the predictions of the PK theory and its previous modified theories. For the solid nematic transition, all theories give very nearly the same results, but the values are significantly lower than the observed data. Moreover, one of the theoretical phase diagrams is also qualitatively similar to the experimental phase diagram for p-azoxyphenetole (PAA).

  3. Investigation of the liquid crystalline phase transitions using the new modified Pople-Karasz model

    International Nuclear Information System (INIS)

    Yazici, Mustafa; Oezgan, Suekrue; Keskin, Mustafa

    2005-01-01

    Thermodynamics of solid-nematic and nematic-isotropic liquid transitions are studied by using a new modified model that combines the modified theories of Chandrasekhar et al. with those Keskin and Oezgan which are based on the Pople-Karasz theory. The thermodynamic properties of the disordered system are evaluated relative to those of the perfectly ordered one within the lowest approximation of the cluster variation method which is identical to the mean-field approximation. The results are compared with the some available experimental data, the predictions of the original Pople-Karasz (PK) theory and its previous modified theories. For nematic-isotropic and s(nematic) at the transition temperatures, the agreement is very good and much better than the predictions of the PK theory and its previous modified theories. For the solid-nematic transition, all theories give very nearly the same results, but the values are significantly lower than the observed data. Moreover, one of the theoretical phase diagrams is also qualitatively similar to the experimental phase diagram for p-azoxyphenetole (PAA)

  4. Experimental investigation of extended Kalman Filter combined with carrier phase recovery for 16-QAM system

    Science.gov (United States)

    Shu, Tong; Li, Yan; Yu, Miao; Zhang, Yifan; Zhou, Honghang; Qiu, Jifang; Guo, Hongxiang; Hong, Xiaobin; Wu, Jian

    2018-02-01

    Performance of Extended Kalman Filter combined with the Viterbi-Viterbi phase estimation (VVPE-EKF) for joint phase noise mitigation and amplitude noise equalization is experimental demonstrated. Experimental results show that, for 11.2 Gbaud SP-16-QAM, the proposed VVPE-EKF achieves 0.9 dB required OSNR reduction at bit error ratio (BER) of 3.8e-3 compared to the VVPE. The result of maximum likelihood combined with VVPE (VVPE-ML) is only 0.3 dB. For 28 GBaud SP-16-QAM signal, VVPE-EKF achieves 3 dB required OSNR reduction at BER=3.8e-3 (7% HD-FEC threshold) compared to VVPE. And VVPE-ML can reduce the required OSNR for 1.7 dB compared to the VVPE. VVPE-EKF outperforms DD-EKF 3.7 dB and 0.7 dB for 11.2 GBaud and 28 GBaud system, respectively.

  5. An investigation of two-phase flow instability using wavelet signal extraction technique

    International Nuclear Information System (INIS)

    Shang Zhi; Yang Ruichang; Cao Xuewu; Yang Yanhua

    2004-01-01

    When the oscillation periods of the instability of two-phase flow are sought with traditional methods of signal analysis, generally the Fourier transform must be employed and then the oscillation periods will be gotten at the location of the local maximum amplitude of frequency transform. However, Fourier transform will be difficult to clearly analyze the unsteady signals especially when the signals include many peaks and the noise interference is not generated by white noise in many areas of practical engineering like the oscillation of the instability of two-phase flow. The most effective solving method for the difficulty of Fourier transform is to analyze the signals directly in time domain. Wavelet analysis is able to search out the periods from time domain directly. It also has more excellent local characteristics than Fourier analysis in the both of time and frequency domains. In this paper, not only is a direct detecting method of the oscillation periods successfully applied based on the wavelet signal extraction techniques, but also the oscillation of density wave type of TYPE I is found as a kind of oscillations with a high-frequency harmonization

  6. Phase identification and structure investigation of novel quaternary rare-earth substituted titanates

    Science.gov (United States)

    Aldridge, James D.; Womick, Jordan M.; Rosmus, Kimberly A.; Weiland, Ashley; Aitken, Jennifer A.; Polvani, Deborah A.

    2017-12-01

    Novel quaternary lanthanide-substituted oxides of stoichiometry LnxY2-xTi2O7 (where Ln is lanthanum, neodymium, samarium, gadolinium, or ytterbium) were prepared by traditional high-temperature, solid-state techniques and characterized by X-ray powder diffraction. Samples with nominal values of x up to 1.0 were attempted. The well-studied ternary cubic pyrochlore compound yttrium titanium oxide (Y2Ti2O7, space group Fd-3m, Z = 8), served as a parent structural framework in which Ln3+ cations were substituted on the Y3+ site. Laboratory-grade X-ray powder diffraction data revealed pure quaternary pyrochlore phases for LnxY2-xTi2O7 with x ≤ 0.2. Pyrochlore phase purity was verified by Rietveld analysis using high-resolution synchrotron X-ray powder diffraction data when x ≤ 0.2, however, for La3+ substitution specifically, pure quaternary pyrochlore formed at x<0.1. Band gap energies on selected samples were determined using optical diffuse reflectance spectroscopy and showed that these materials can be classified as electrical insulators with indirect band gap energies around 3.7 eV.

  7. Investigation of properties and performance of ceramic composite components: Final report on Phases 3 and 4

    Energy Technology Data Exchange (ETDEWEB)

    Curtin, W.A.; Halverson, H.; Carter, R.H.; Miraj, N.; Reifsnider, K.L. [Virginia Polytechnic Inst. and State Univ., Blacksburg, VA (United States)

    1998-01-15

    The objective of the Fossil Energy Advanced Research and Technology Development (AR and TD) Materials Program is to conduct research and development on materials for longer-term fossil energy applications as well as for generic needs of various fossil fuel technologies. The research program of the Materials Response Group at Virginia Tech addresses the need for reliable and durable structural ceramic composites to perform in high temperature environments. The research effort provides an experimental and analytical basis for the transition from properties of materials to performance of actual component structures. Phases 1 and 2 of the present program focused on the development of test capabilities, initial studies of component mechanical response under various conditions and the development of a life prediction methodology. These efforts have been described in previous reports. This report summarizes the major tasks completed under Phases 3 and 4 of the project. Overall, the authors have made significant progress in a broad spectrum of tasks in this program. Their efforts have encompassed component evaluation, assessment of new SiC-based composites with improved high-temperature potential, development of oxide coating materials for SiC, and the extension and development of new models for predicting the durability of composite components under specific operating conditions for various CMC applications. Each of these areas of work is an important area for achieving the ultimate goal of usable SiC-based composites in high-temperature corrosive environments typical of fossil energy applications.

  8. Investigating Structure and Dynamics of Proteins in Amorphous Phases Using Neutron Scattering

    Directory of Open Access Journals (Sweden)

    Maria Monica Castellanos

    Full Text Available In order to increase shelf life and minimize aggregation during storage, many biotherapeutic drugs are formulated and stored as either frozen solutions or lyophilized powders. However, characterizing amorphous solids can be challenging with the commonly available set of biophysical measurements used for proteins in liquid solutions. Therefore, some questions remain regarding the structure of the active pharmaceutical ingredient during freezing and drying of the drug product and the molecular role of excipients. Neutron scattering is a powerful technique to study structure and dynamics of a variety of systems in both solid and liquid phases. Moreover, neutron scattering experiments can generally be correlated with theory and molecular simulations to analyze experimental data. In this article, we focus on the use of neutron techniques to address problems of biotechnological interest. We describe the use of small-angle neutron scattering to study the solution structure of biological molecules and the packing arrangement in amorphous phases, that is, frozen glasses and freeze-dried protein powders. In addition, we discuss the use of neutron spectroscopy to measure the dynamics of glassy systems at different time and length scales. Overall, we expect that the present article will guide and prompt the use of neutron scattering to provide unique insights on many of the outstanding questions in biotechnology. Keywords: Neutron scattering, Protein structure, Protein dynamics, Freeze-dried proteins, Glasses, Frozen protein solutions, Molecular dynamics

  9. Investigation of Thermal Interface Materials Using Phase-Sensitive Transient Thermoreflectance Technique: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Feng, X.; King, C.; DeVoto, D.; Mihalic, M.; Narumanchi, S.

    2014-08-01

    With increasing power density in electronics packages/modules, thermal resistances at multiple interfaces are a bottleneck to efficient heat removal from the package. In this work, the performance of thermal interface materials such as grease, thermoplastic adhesives and diffusion-bonded interfaces are characterized using the phase-sensitive transient thermoreflectance technique. A multi-layer heat conduction model was constructed and theoretical solutions were derived to obtain the relation between phase lag and the thermal/physical properties. This technique enables simultaneous extraction of the contact resistance and bulk thermal conductivity of the TIMs. With the measurements, the bulk thermal conductivity of Dow TC-5022 thermal grease (70 to 75 um bondline thickness) was 3 to 5 W/(m-K) and the contact resistance was 5 to 10 mm2-K/W. For the Btech thermoplastic material (45 to 80 μm bondline thickness), the bulk thermal conductivity was 20 to 50 W/(m-K) and the contact resistance was 2 to 5 mm2-K/W. Measurements were also conducted to quantify the thermal performance of diffusion-bonded interface for power electronics applications. Results with the diffusion-bonded sample showed that the interfacial thermal resistance is more than one order of magnitude lower than those of traditional TIMs, suggesting potential pathways to efficient thermal management.

  10. Investigation on two-phase flow stability in a natural circulation system

    International Nuclear Information System (INIS)

    Wu Shaorung; Jia Haijun; Jiang Shengyiao; Zhang Youjie

    2000-01-01

    A research program on thermal-hydrodynamic stability of the two-phase flow, simulating the behavior in the primary loop of a nuclear heating reactor developed by the Tsinghua University institute of nuclear energy technology (INET) in China has been executed for several years. In the integrated primary loop of the NHR heating reactor, the natural circulation of the coolant water was adopted with low system pressure, low steam quality at the exit of the core and a relatively long riser above the core. It is important to keep the reactor operating under stable conditions with enough safety margins. The program was aimed at: (1) accumulating experimental data for verification of the models and codes used in the design and safety analysis of this type of reactor; (2) understanding the unstable behavior, its physical mechanisms and parameter effects. The results of the study show that under certain geometric conditions and operating parameters a self-sustaining, low frequency, even amplitude mass flow oscillation may be excited at very low steam qualities. Stability maps under different conditions are provided. An unstable region, which exists between the single-phase stable region and the low steam quality bulk boiling stable region, was experimentally demonstrated. (orig.) [de

  11. Three-dimensional investigation of the two-phase flow structure in a bubbly pipe flow

    International Nuclear Information System (INIS)

    Hassan, Y.A.; Schmidl, W.D.; Ortiz-Villafuerte, J.

    1997-01-01

    Particle Image Velocimetry (PIV) is a non-intrusive measurement technique, which can be used to study the structure of various fluid flows. PIV is used to measure the time varying full field velocity data of a particle-seeded flow field within either a two-dimensional plane or three-dimensional volume. PIV is a very efficient measurement technique since it can obtain both qualitative and quantitative spatial information about the flow field being studied. This information can be further processed into information such as vorticity and pathlines. Other flow measurement techniques (Laser Doppler Velocimetry, Hot Wire Anemometry, etc...) only provide quantitative information at a single point. PIV can be used to study turbulence structures if a sufficient amount of data can be acquired and analyzed, and it can also be extended to study two-phase flows if both phases can be distinguished. In this study, the flow structure around a bubble rising in a pipe filled with water was studied in three-dimensions. The velocity of the rising bubble and the velocity field of the surrounding water was measured. Then the turbulence intensities and Reynolds stresses were calculated from the experimental data. (author)

  12. Correction: Electrochemical Investigation of the Corrosion of Different Microstructural Phases of X65 Pipeline Steel under Saturated Carbon Dioxide Conditions. Materials 2015, 8, 2635–2649

    Directory of Open Access Journals (Sweden)

    Yuanfeng Yang

    2015-12-01

    Full Text Available In the published manuscript “Electrochemical Investigation of the Corrosion of Different Microstructural Phases of X65 Pipeline Steel under Saturated Carbon Dioxide Conditions. [...

  13. Experimental investigation of the U–Zr–Al ternary phase diagram: Isothermal sections at 673 K and 1073 K

    Energy Technology Data Exchange (ETDEWEB)

    Moussa, C.; Désévédavy, F.; Noël, H.; Pasturel, M.; Gouttefangeas, F. [ISCR/CSM, Université de Rennes1, UMR-CNRS 6226, Campus de Beaulieu, 263 Avenue du Général Leclerc, 35042 Rennes Cedex, France, (France); Dubois, S. [CEA/DEN/DEC, Cadarache, 13108 St. Paul Lez Durance (France); Stepnik, B. [AREVA/CERCA, 10 Rue Juliette Récamier, 69006 Lyon (France); Tougait, O., E-mail: tougait@univ-rennes1.fr [ISCR/CSM, Université de Rennes1, UMR-CNRS 6226, Campus de Beaulieu, 263 Avenue du Général Leclerc, 35042 Rennes Cedex, France, (France); UCCS, UMR 8181 CNRS, Université Lille 1, ENSCL, Avenue Mendeleiev, 59655 Villeneuve d’Ascq Cedex (France)

    2015-06-15

    Highlights: • Isothermal sections of the U–Zr–Al system were investigated for 673 K and 1073 K. • The crystallographic properties of the equilibrium phases were checked. • The ternary extension of both unary and binary phases was determined. • The solubility of Al into UZr{sub 2} (δ-phase) was assessed by diffusion couples. • The microstructure of quenched alloys is discussed. - Abstract: Isothermal sections at 673 K and 1073 K of the ternary U–Zr–Al system were established in the whole concentration range, by means of powder X-ray diffraction, scanning electron microscopy–energy dispersive X-ray spectroscopy and differential thermal analysis. All measured compositions and unit-cell refinements were performed at room temperature from quenched samples annealed at 1073 K and 673 K for four and eight weeks respectively. For both temperatures, the Al-rich corner of the phase diagram is characterized by extended homogeneity ranges due to mutual exchange between U and Zr in UAl{sub 3} (cubic, AuCu{sub 3}-type) and in the Laves phase UAl{sub 2} (cubic, MgCu{sub 2}-type). Minute U solubility in ZrAl{sub 2} (hexagonal, MgZn{sub 2}-type) and in Zr{sub 2}Al (hexagonal, Ni{sub 2}In-type) was evaluated to be of the order of 1 at.% U. For the other binary compounds, the solubility of the third component was found negligible. At 1073 K, the solid solution based on γU (cubic, W-type) which covers the U–Zr binary axis up to 95.5 at.% Zr, allows also some limited solubility of Al [maximum of 5 at.%]. For Al-content below 66 at.%, most of the phase relations comprise equilibria between the Zr–Al binaries and the γ(U,Zr,Al) solid solution. At 673 K, the U–Zr axis is found in agreement with the literature data and no Al solubility could be detected in αU, αZr and UZr{sub 2} (δ phase). The phase relations are mainly established between Zr–Al binaries and αU. For monolithic UMo fuel with a Zr diffusion barrier foil cladded with Al, the main interaction

  14. Experimental investigation of the U–Zr–Al ternary phase diagram: Isothermal sections at 673 K and 1073 K

    International Nuclear Information System (INIS)

    Moussa, C.; Désévédavy, F.; Noël, H.; Pasturel, M.; Gouttefangeas, F.; Dubois, S.; Stepnik, B.; Tougait, O.

    2015-01-01

    Highlights: • Isothermal sections of the U–Zr–Al system were investigated for 673 K and 1073 K. • The crystallographic properties of the equilibrium phases were checked. • The ternary extension of both unary and binary phases was determined. • The solubility of Al into UZr 2 (δ-phase) was assessed by diffusion couples. • The microstructure of quenched alloys is discussed. - Abstract: Isothermal sections at 673 K and 1073 K of the ternary U–Zr–Al system were established in the whole concentration range, by means of powder X-ray diffraction, scanning electron microscopy–energy dispersive X-ray spectroscopy and differential thermal analysis. All measured compositions and unit-cell refinements were performed at room temperature from quenched samples annealed at 1073 K and 673 K for four and eight weeks respectively. For both temperatures, the Al-rich corner of the phase diagram is characterized by extended homogeneity ranges due to mutual exchange between U and Zr in UAl 3 (cubic, AuCu 3 -type) and in the Laves phase UAl 2 (cubic, MgCu 2 -type). Minute U solubility in ZrAl 2 (hexagonal, MgZn 2 -type) and in Zr 2 Al (hexagonal, Ni 2 In-type) was evaluated to be of the order of 1 at.% U. For the other binary compounds, the solubility of the third component was found negligible. At 1073 K, the solid solution based on γU (cubic, W-type) which covers the U–Zr binary axis up to 95.5 at.% Zr, allows also some limited solubility of Al [maximum of 5 at.%]. For Al-content below 66 at.%, most of the phase relations comprise equilibria between the Zr–Al binaries and the γ(U,Zr,Al) solid solution. At 673 K, the U–Zr axis is found in agreement with the literature data and no Al solubility could be detected in αU, αZr and UZr 2 (δ phase). The phase relations are mainly established between Zr–Al binaries and αU. For monolithic UMo fuel with a Zr diffusion barrier foil cladded with Al, the main interaction product is expected to involve the U

  15. Theoretical Investigation of the Structural Stabilities of Ceria Surfaces and Supported Metal Nanocluster in Vapor and Aqueous Phases

    Energy Technology Data Exchange (ETDEWEB)

    Ren, Zhibo [State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing 100029, China; Institute for Integrated Catalysis, Pacific Northwest National Laboratory, Richland, Washington 99352, United States; Liu, Ning [State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing 100029, China; Institute for Integrated Catalysis, Pacific Northwest National Laboratory, Richland, Washington 99352, United States; Chen, Biaohua [State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing 100029, China; Li, Jianwei [State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing 100029, China; Mei, Donghai [Institute for Integrated Catalysis, Pacific Northwest National Laboratory, Richland, Washington 99352, United States

    2018-01-25

    Understanding the structural stability and dynamics at the interface between the solid metal oxide and aqueous phase is significant in a variety of industrial applications including heterogeneous catalysis and environmental remediation. In the present work, the stabilities of three low-index ceria (CeO2) surfaces, i.e., (111), (110) and (100) in vapor and aqueous phases were studied using ab initio molecular dynamics simulations and density functional theory (DFT) calculations. Gibbs surface free energies as a function of temperature, water partial pressure, and water coverages were calculated using DFT based atomistic thermodynamic approach. On the basis of surface free energies, the morphology and exposed surface structures of the CeO2 nanoparticle were predicted using Wulff construction principle. It is found that the partially hydroxylated (111) and (100) are two major surface structures of CeO2 nanoparticles in vapor phase at ambient temperature (300 K). As the temperature increases, the fully dehydrated (111) surface gradually becomes the most dominant surface structure. While in aqueous phase, the exposed surface of the CeO2 nanoparticle is dominated by the hydroxylated (110) structure at 393 K. Finally, the morphology and stability of a cuboctahedron Pt13 nanocluster supported on CeO2 surfaces in both gas and aqueous phases were investigated. In gas phase, the supported Pt13 nanocluster has the tendency to wetting the CeO2 surface due to the strong metal-support interaction. The calculated interaction energies suggest the CeO2(110) surface provides the best stability for the Pt13 nanocluster. The CeO2 supported Pt13 nanoclusters are oxidized. Compared to the gas phase, the morphology of the CeO2 supported Pt13 nanocluster is less distorted due to the solvation effect provided by surrounding water molecules in aqueous phase. More electrons are transferred from the Pt13 nanocluster to the CeO2 support, implying the supported Pt13 nanocluster is further

  16. Investigating Solutions to Wind Washing Issues in Two-Story Florida Homes, Phase 2

    Energy Technology Data Exchange (ETDEWEB)

    Withers, C. [Building America Partnership for Improved Residential Construction, Cocoa, FL (United States); Kono, J. [Building America Partnership for Improved Residential Construction, Cocoa, FL (United States)

    2015-04-01

    This report provides results from a second-phase research study of a phenomenon generally referred to as wind washing. Wind washing is the movement of unconditioned air around or through building thermal barriers in such a way as to diminish or nullify the intended thermal performance. In some cases, thermal and air barriers are installed very poorly or not at all, and air can readily move from unconditioned attic spaces into quasi-conditioned interstitial spaces. This study focused on the impact of poorly sealed and insulated floor cavities adjacent to attic spaces in Florida homes. In these cases, unconditioned attic air can be transferred into floor cavities through pathways driven by natural factors such as wind, or by thermal differences between the floor cavity and the attic. Air can also be driven into a floor cavity through mechanical forces imposed by return duct leakage in the floor cavity.

  17. Investigation of biomedical inner microstructures with hard X-ray phase-contrast imaging

    Energy Technology Data Exchange (ETDEWEB)

    Shu Hang [Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, CAS, 100049 Beijing (China); Graduate University of the Chinese Academy of Sciences, 100864 Beijing (China); Zhu Peiping [Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, CAS, 100049 Beijing (China); Chen Bo [Department of Physics, University of Science and Technology of China, Hefei 230026 (China); Liu Bo; Yin Hongxia [Capital University of Medical Sciences, 100054 Beijing (China); Li Enrong [Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, CAS, 100049 Beijing (China); Graduate University of the Chinese Academy of Sciences, 100864 Beijing (China); Liu Yijin [Department of Physics, University of Science and Technology of China, Hefei 230026 (China); Wang Junyue [Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, CAS, 100049 Beijing (China); Graduate University of the Chinese Academy of Sciences, 100864 Beijing (China); Yuan Qingxi; Huang Wanxia; Fang Shouxian [Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, CAS, 100049 Beijing (China); Wu Ziyu [Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, CAS, 100049 Beijing (China); National Center for NanoScience and Technology, 100080 Beijing (China)], E-mail: wuzy@ihep.ac.cn

    2007-09-21

    Hard X-ray Phase-Contrast Imaging (HX-PCI) is a new and valuable method that may provide information of the inner parts of an opaque object. Previous reports demonstrated its applicability in soft and hard tissue imaging. Here we provide further evidence for improved image quality and the effective capability to distinguish inner microstructures in real biomedical systems such as cochlea. Experiments performed both at the 4W1A beamline of the Beijing Synchrotron Radiation Facility (BSRF) and at the Taiwan National Synchrotron Radiation Research Center (NSRRC) clearly show details of samples' inner microstructure with a resolution of a few microns. The improved spatial resolution is a relevant achievement for future improved understanding and clinical trials.

  18. Quality investigation of surface mount technology using phase-shifting digital holography

    Science.gov (United States)

    Boonsri, Chantira; Buranasiri, Prathan

    2016-09-01

    Applying of a phase-shifting digital holography combined with compressive sensing to inspect the soldering quality of surface mount technology (SMT) which is a method for producing electronic circuits. In SMT, the components are mounted and connected with each other directly onto the surface of printed circuit boards (PCBs). By reconstructing the multidimensional images from a few samples of SMT, the results are solved by an optimization problem. In this paper, two problems have been concerned. The first one is to examine the devices and the soldering quality of connections between them, which are in micro-scaled. The second is to observe the effect of heat treatment of soldering material and devices on the surface mount board.

  19. An experimental and numerical investigation of crossflow effects in two-phase displacements

    DEFF Research Database (Denmark)

    Cinar, Y.; Jessen, Kristian; Berenblyum, Roman

    2006-01-01

    In this paper, we present flow visualization experiments and numerical simulations that demonstrate the combined effects of viscous and capillary forces and gravity segregation on crossflow that occurs in two-phase displacements in layered porous media. We report results of a series of immiscible...... (IFT) by varying the isopropanol concentration. Experiments were performed for a wide range of capillary and gravity numbers. The experimental results illustrate the transitions from flow dominated by capillary pressure at high IFT to flow dominated by gravity and viscous forces at low IFT...... experiments by two different numerical techniques: finite-difference and streamline methods. The numerical simulation results agree well with experimental observations when gravity and viscous forces were most important. For capillary-dominated flows, the simulation results are in reasonable agreement...

  20. Gas-phase conformations of 2-methyl-1,3-dithiolane investigated by microwave spectroscopy

    Science.gov (United States)

    Van, Vinh; Stahl, Wolfgang; Schwell, Martin; Nguyen, Ha Vinh Lam

    2018-03-01

    The conformational analysis of 2-methyl-1,3-dithiolane using quantum chemical calculations at some levels of theory yielded only one stable conformer with envelope geometry. However, other levels of theory indicated two envelope conformers. Analysis of the microwave spectrum recorded using two molecular jet Fourier transform microwave spectrometers covering the frequency range from 2 to 40 GHz confirms that only one conformer exists under jet conditions. The experimental spectrum was reproduced using a rigid-rotor model with centrifugal distortion correction within the measurement accuracy of 1.5 kHz, and molecular parameters were determined with very high accuracy. The gas phase structure of the title molecule is compared with the structures of other related molecules studied under the same experimental conditions.

  1. Experimental investigation of a two-phase closed thermosyphon assembly for passive containment cooling system

    Energy Technology Data Exchange (ETDEWEB)

    Nam, Kyung Ho [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Kim, Sang Nyung [Kyunghee Univ., Gyeonggi-do (Korea, Republic of)

    2017-06-15

    After the Fukushima accident, increasing interest has been raised in passive safety systems that maintain the integrity of the containment building. To improve the reliability and safety of nuclear power plants, long-term passive cooling concepts have been developed for advanced reactors. In a previous study, the proposed design was based on an ordinary cylindrical Two-Phase Closed Thermosyphon (TPCT). The exact assembly size and number of TPCTs should be elaborated upon through accurate calculations based on experiments. While the ultimate goal is to propose an effective MPHP design for the PCCS and experimentally verify its performance, a TPCT assembly that was manufactured based on the conceptual design in this paper was tested.

  2. Experimental and theoretical investigations on the phase purity of GaAs zincblende nanowires

    Science.gov (United States)

    Ren, X.; Huang, H.; Dubrovskii, V. G.; Sibirev, N. V.; Nazarenko, M. V.; Bolshakov, A. D.; Ye, X.; Wang, Q.; Huang, Y.; Zhang, X.; Guo, J.; Liu, X.

    2011-01-01

    Interesting phenomena of GaAs nanowire growth have been observed. The nanowires were grown by metal-organic chemical vapor deposition (MOCVD) on GaAs (1 1 1)B substrates with an Au catalyst at 464 °C. The growth rates of all nanowires were almost the same for a fixed density of Au nanodrops. TEM analysis demonstrates a stacking-fault-free zincblende structure of the nanowires even when their radius is reduced to as small as 12 nm. A theoretical model is developed that is capable of describing the critical radius of zincblende to wurtzite phase transition as a function of vapor supersaturation and material constants. The model shows that the surprising prevalence of the zincblende structure should originate from very high supersaturations during MOCVD.

  3. Experimental and theoretical investigations on the phase purity of GaAs zincblende nanowires

    International Nuclear Information System (INIS)

    Ren, X; Huang, H; Ye, X; Wang, Q; Huang, Y; Zhang, X; Guo, J; Liu, X; Dubrovskii, V G; Sibirev, N V; Nazarenko, M V; Bolshakov, A D

    2011-01-01

    Interesting phenomena of GaAs nanowire growth have been observed. The nanowires were grown by metal-organic chemical vapor deposition (MOCVD) on GaAs (1 1 1)B substrates with an Au catalyst at 464 °C. The growth rates of all nanowires were almost the same for a fixed density of Au nanodrops. TEM analysis demonstrates a stacking-fault-free zincblende structure of the nanowires even when their radius is reduced to as small as 12 nm. A theoretical model is developed that is capable of describing the critical radius of zincblende to wurtzite phase transition as a function of vapor supersaturation and material constants. The model shows that the surprising prevalence of the zincblende structure should originate from very high supersaturations during MOCVD

  4. A mass spectrometric investigation of the exchange of deuterium with tetraborane(10) in the gas phase

    International Nuclear Information System (INIS)

    Greatrex, R.; Greenwood, N.N.; Potter, C.D.

    1984-01-01

    Mass spectrometry has been used to establish direct exchange between dideuterium (D 2 ) and B 4 H 10 in the gas phase. In a mixture of stoicheiometry B 4 H 10 :3D 2 at 42 deg C, ca. 7% of the hydrogen atoms were replaced by deuterium in 130 min. The possibility that the exchange might be occurring by an indirect or autocatalytic mechanism was eliminated by a series of experiments in which the rate of exchange was shown to be independent of small admixtures of the decomposition products. The present work resolves a troublesome inconsistency in the literature and strengthens the view that the equilibrium B 4 H 10 brace B 4 H 8 brace + H 2 plays a key role in borane interconversion reactions. (author)

  5. Improving Performance of Cold-Chain Insulated Container with Phase Change Material: An Experimental Investigation

    Directory of Open Access Journals (Sweden)

    Li Huang

    2017-12-01

    Full Text Available The cold-chain transportation is an important means to ensure the drug and food safety. An cold-chain insulated container incorporating with Phase Change Material (PCM has been developed for a temperature-controlled transportation in the range of 2~8 °C. The container configuration and different preconditioning methods have been determined to realize a 72-h transportation under extremely high, extremely low, and alternating temperature conditions. The experimental results showed that the temperature-controlled time was extended from 1 h to more than 80 h and the internal temperature maintained at 4~5 °C by using a PCM with a melting/freezing point of 5 °C, while the container presented a subcooling effect in a range of −1~2 °C when using water as PCM. The experimental values of the temperature-controlled time agreed well with the theoretical values.

  6. Out of phase thermal mechanical fatigue investigation of a directionally solidified superalloy DZ125

    Directory of Open Access Journals (Sweden)

    Hu Xiaoan

    2016-02-01

    Full Text Available Out of phase (OP thermal mechanical fatigue (TMF behavior of a directionally solidified (DS superalloy DZ125 was experimentally and numerically studied. Two different temperature conditions, which are 500–1000 °C and 400–900 °C, were considered in the present research. Stress and strain responses as well as fatigue life results were presented and discussed. Scanning electron microscope (SEM and metallographic analysis were used to study the damage mechanism. An oxidation assisted crack initiation and propagation phenomenon were found to explain the shorted life under TMF cycles. In order to characterize the stress and strain deformations under TMF loadings, a modified Chaboche’s constitutive model was applied. Additionally, the TMF life of the material was modeled and predicted by Neu–Sehitoglu damage law with high accuracy.

  7. Symmetry analysis in the investigation of the order-disorder phase transition and possible structural deformations

    International Nuclear Information System (INIS)

    Gurin, O.V.; Syromyatnikov, V.N.

    1984-01-01

    Order-disorder phase transitions for the Me-X structures in Nb-H(D) hydrides with hydrogen (deuterium) ordering over the 12d tetrahedral interstices of the GAMMAsub(c)sup(v) lattice and for the Me-X and Me-X 2 oxides in the Ta-O system with oxygen ordering over octahedral 6b interstices are presented. The concentration of interstitial atoms is assumed to be constant. All possible models of ordered structures with a GAMMAsub(o)sup(b) lattice were determined using symmetry analysis. The possible structural deformations consistent with each variant of the ordering of the interstitial atoms were also considered. The structural deformations include the displacements of the metal atoms and of the centres of the interstices which were deduced using symmetry analysis. The results of the analysis of the final structure symmetry raise the question of understanding the nature of superstructure reflections in neutron diffraction patterns. (Auth.)

  8. Experimental investigations of turbulent temperature fluctuations and phase angles in ASDEX Upgrade

    Science.gov (United States)

    Freethy, Simon

    2017-10-01

    A complete experimental understanding of the turbulent fluctuations in tokamak plasmas is essential for providing confidence in the extrapolation of heat transport models to future experimental devices and reactors. Guided by ``predict first'' nonlinear gyrokinetic simulations with the GENE code, two new turbulence diagnostics were designed and have been installed on ASDEX Upgrade (AUG) to probe the fundamentals of ion-scale turbulent electron heat transport. The first, a 30-channel correlation ECE (CECE) radiometer, measures radial profiles (0.5 mode. Typical L-mode levels are in the range 0.3 - 0.8%. The second is formed by the addition of a reflectometer on the same line of sight to enable measurements of the phase angle between turbulent density and temperature fluctuations. Design predictions are followed by a more traditional ``post-diction'' validation study with GENE. Using a cutting edge synthetic diagnostic GENE shows a factor 1.6 - 2 over-prediction of the fluctuation amplitude, while matching both ion and electron heat fluxes within experimental error. Detailed sensitivity scans are underway to understand the robustness of this disagreement and a detailed assessment of the experimental errors has been carried out. The discrepancy opens questions about the role of multi-scale turbulence physics, but also indicates the need for the comparison of more experimental turbulence properties to have a more complete validation hierarchy. In an effort to understand the discrepancy, predictions of the nT-phase and the radial correlation length have been made along with an assessment of their sensitivity to experimental errors. Comparison to experimental measurements will be discussed. This work is supported in part by the US DOE under Grants DE-SC0006419 and DE-SC0017381. This work has also received funding from the European Union's Horizon 2020 research and innovation programme under Grant agreement number 633053.

  9. Experimental investigation of effect of spacer on two phase turbulent mixing rate in subchannels of pressure tube type BWR

    Energy Technology Data Exchange (ETDEWEB)

    Verma, Shashi Kant; Sinha, S.L. [National Institute of Technology, Raipur (India). Mechanical Engineering Dept.; Chandraker, D.K. [Bhabha Atomic Research Centre, Mumbai (India). Reactor Design and Development Group

    2017-11-15

    Turbulent mixing rate between adjacent subchannels in a two-phase flow has been known to be strongly dependent on the flow pattern. The most important aspect of turbulent motion is that the velocity and pressure at a fixed point do not remain constant with time even in steady state but go through very irregular high frequency fluctuations. These fluctuations influence the diffusion of scalar and vector quantities. The Advanced Heavy Water Reactor (AHWR) is a vertical pressure tube type, heavy water moderated and boiling light water cooled natural circulation based reactor. The fuel bundle of AHWR contains 54 fuel rods set in three concentric rings of 12, 18 and 24 fuel rods. This fuel bundle is divided into number of imaginary interacting flow channel called subchannels. Alteration from single phase to two phase flow situation occurs in reactor rod bundle with raise in power. The two phase flow regimes like bubbly, slug-churn, and annular flow are generally encountered in reactor rod bundle. Prediction of thermal margin of the reactor has necessitated the investigation of turbulent mixing rate of coolant between these subchannels under these flow regimes. Thus, it is fundamental to estimate the effect of spacer grids on turbulent mixing between subchannels of AHWR rod bundle.

  10. Review of Available Data for Validation of Nuresim Two-Phase CFD Software Applied to CHF Investigations

    Directory of Open Access Journals (Sweden)

    D. Bestion

    2009-01-01

    Full Text Available The NURESIM Project of the 6th European Framework Program initiated the development of a new-generation common European Standard Software Platform for nuclear reactor simulation. The thermal-hydraulic subproject aims at improving the understanding and the predictive capabilities of the simulation tools for key two-phase flow thermal-hydraulic processes such as the critical heat flux (CHF. As part of a multi-scale analysis of reactor thermal-hydraulics, a two-phase CFD tool is developed to allow zooming on local processes. Current industrial methods for CHF mainly use the sub-channel analysis and empirical CHF correlations based on large scale experiments having the real geometry of a reactor assembly. Two-phase CFD is used here for understanding some boiling flow processes, for helping new fuel assembly design, and for developing better CHF predictions in both PWR and BWR. This paper presents a review of experimental data which can be used for validation of the two-phase CFD application to CHF investigations. The phenomenology of DNB and Dry-Out are detailed identifying all basic flow processes which require a specific modeling in CFD tool. The resulting modeling program of work is given and the current state-of-the-art of the modeling within the NURESIM project is presented.

  11. Phase 1 - Test Area Investigation Report : Mine Research Project GUE-70-14.10 : Executive Summary

    Science.gov (United States)

    2001-01-01

    The GUE-70-14.10 Mine Research Project is the investigation of a 2,200-foot-long section of : Interstate 70 in Guernsey County, Ohio. Portions of the project area pavement were damaged as a : result of mine subsidence. The damaged areas were remediat...

  12. Phase II - Test Area Investigation Report : Mine Research Project GUE - 70-14.10 : Executive Summary

    Science.gov (United States)

    2001-01-01

    The GUE-70-14.10 Mine Research Project is the investigation of a 2,100-foot-long section : of Interstate 70 in Guernsey County, Ohio. Portions of the Project Area pavement were : damaged as a result of mine subsidence. The damaged areas and other min...

  13. Theoretical investigation of phase transition on GaAs(0 0 1)-c(4 x 4) surface

    International Nuclear Information System (INIS)

    Ishizaki, Hirotoshi; Akiyama, Toru; Nakamura, Kohji; Shiraishi, Kenji; Taguchi, Akihito; Ito, Tomonori

    2005-01-01

    The surface phase transition between GaAs(0 0 1)-c(4 x 4) and -(2 x 4)β2 surfaces is systematically investigated by using our ab initio-based approach. The phase diagram calculations for the c(4 x 4) surfaces as functions of temperature and As pressure reveal that three kinds of c(4 x 4) surfaces consisting of Ga-As dimers and/or Ga-Ga dimers become stable near the phase transition temperature. The electron counting Monte Carlo simulation and ab initio calculations are also performed to investigate the structural change of the c(4 x 4) surface after predepositing a 0.5 monolayer of Ga on the three kinds of c(4 x 4) surfaces. The calculated results suggest that the c(4 x 4) surfaces consisting of three Ga-As dimers or one Ga-Ga dimer and two Ga-As dimers in the (4 x 4) surface unit cell possibly change their structures to (2 x 4)β2 structures with Ga-As surface dimers. The conventional (2 x 4)β2 surface consisting of As dimers finally appears due to destabilization of Ga-As dimers at high temperature and high pressure

  14. In situ investigation of ordering phase transformations in FePt magnetic nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Wittig, James E., E-mail: j.wittig@vanderbilt.edu [Interdisciplinary Materials Science, Vanderbilt University, PMB 351683, 2301 Vanderbilt Place, Nashville, TN 37232 (United States); Bentley, James, E-mail: bentleyj48@gmail.com [Materials Science and Technology Division, Oak Ridge National Laboratory, PO Box 2008, Oak Ridge, TN 37831-6376 (United States); Allard, Lawrence F., E-mail: allardlfjr@ornl.gov [Materials Science and Technology Division, Oak Ridge National Laboratory, PO Box 2008, Oak Ridge, TN 37831-6376 (United States)

    2017-05-15

    In situ high-resolution electron microscopy was used to reveal information at the atomic level for the disordered-to-ordered phase transformation of equiatomic FePt nanoparticles that can exhibit outstanding magnetic properties after transforming from disordered face-centered-cubic into the tetragonal L1{sub 0} ordered structure. High-angle annular dark-field imaging in the scanning transmission electron microscope provided sufficient contrast between the Fe and Pt atoms to readily monitor the ordering of the atoms during in situ heating experiments. However, during continuous high-magnification imaging the electron beam influenced the kinetics of the transformation so annealing had to be performed with the electron beam blanked. At 500 °C where the reaction rate was relatively slow, observation of the transformation mechanisms using this sequential imaging protocol revealed that ordering proceeded from (002) surface facets but was incomplete and multiple-domain particles were formed that contained anti-phase domain boundaries and anti-site defects. At 600 and 700 °C, the limitations of sequential imaging were revealed as a consequence of increased transformation kinetics. Annealing for only 5 min at 700 °C produced complete single-domain L1{sub 0} order; such single-domain particles were more spherical in shape with (002) facets. The in situ experiments also provided information concerning nanoparticle sintering, coalescence, and consolidation. Although there was resistance to complete sintering due to the crystallography of L1{sub 0} order, the driving force from the large surface-area-to-volume ratio resulted in considerable nanoparticle coalescence, which would render such FePt nanoparticles unsuitable for use as magnetic recording media. Comparison of the in situ data acquired using the protocol described above with parallel ex situ annealing experiments showed that identical behavior resulted in all cases. - Highlights: • HAADF STEM imaging reveals the

  15. Quantum phase transitions and local magnetism in Mott insulators: A local probe investigation using muons, neutrons, and photons

    Science.gov (United States)

    Frandsen, Benjamin A.

    destroyed at the quantum phase transition. Taken together, these findings point unambiguously to a first-order quantum phase transition in these systems. We also conducted x-ray and neutron PDF experiments, which suggest that the distinct atomic structures associated with the insulating and metallic phases similarly coexist near the quantum phase transition. These results have significant implications for our understanding of the Mott metal-insulator quantum phase transition in real materials. The second part of this thesis centers on the derivation and development of the magnetic pair distribution function (mPDF) technique and its application to the antiferromagnetic Mott insulator MnO. The atomic PDF method involves Fourier transforming the x-ray or neutron total scattering intensity from reciprocal space into real space to directly reveal the local atomic correlations in a material, which may deviate significantly from the average crystallographic structure of that material. Likewise, the mPDF method involves Fourier transforming the magnetic neutron total scattering intensity to probe the local correlations of magnetic moments in the material, which may exist on short length scales even when the material has no long-range magnetic order. After deriving the fundamental mPDF equations and providing a proof-of-principle by recovering the known magnetic structure of antiferromagnetic MnO, we used this technique to investigate the short-range magnetic correlations that persist well into the paramagnetic phase of MnO. By combining the mPDF measurements with ab initio calculations of the spin-spin correlation function in paramagnetic MnO, we were able to quantitatively account for the observed mPDF. We also used the mPDF data to evaluate competing ab initio theories, thereby resolving some longstanding questions about the magnetic exchange interactions in MnO.

  16. Investigation of vertical slug flow with advanced two-phase flow instrumentation

    International Nuclear Information System (INIS)

    Mi, Y.; Ishii, M.; Tsoukalas, L.H.

    2001-01-01

    Extensive experiments of vertical slug flow were carried out with an electromagnetic flowmeter and an impedance void-meter in an air-water two-phase experimental loop. The basic principles of these instruments in vertical slug flow measurements are discussed. Time series of the liquid velocity and the impedance were separated into two parts corresponding to the Taylor bubble and the liquid slug. Characteristics of slug flow, such as the void fractions, probabilities and lengths of the Taylor bubble and liquid slug, slug unit velocity, area-averaged liquid velocity, and liquid film velocity of the Taylor bubble tail, etc., were obtained. For the first time, the area-averaged liquid velocity of slug flow was revealed by the electromagnetic flowmeter. It is realized that the void fraction of the liquid slug is determined by the turbulent intensity due to the relative liquid motion between the Taylor bubble tail region and its wake region. A correlation of the void fraction of the liquid slug is developed based on experimental results obtained from a test section with 50.8 mm i.d. The results of this study suggest a promising improvement in understanding of vertical slug flow

  17. Investigating Solutions to Wind Washing Issues in Two-Story Florida Homes, Phase 2

    Energy Technology Data Exchange (ETDEWEB)

    Withers, Charles R. [Florida Solar Energy Center, Cocoa, FL (United States); Kono, Jamie [Florida Solar Energy Center, Cocoa, FL (United States)

    2015-04-13

    With U.S. Department of Energy goals of reducing existing home energy use by 30% and new home energy use by 50%, it is imperative to focus on several energy efficiency measures, including the quality of air and thermal barriers. This report provides results from a second-phase research study of a phenomenon generally referred to as wind washing. Wind washing is the movement of unconditioned air around or through building thermal barriers in such a way as to diminish or nullify the intended thermal performance. In some cases, thermal and air barriers are installed very poorly or not at all, and air can readily move from unconditioned attic spaces into quasi-conditioned interstitial spaces. This study focused on the impact of poorly sealed and insulated floor cavities adjacent to attic spaces in Florida homes. In these cases, unconditioned attic air can be transferred into floor cavities through pathways driven by natural factors such as wind, or by thermal differences between the floor cavity and the attic. Air can also be driven into a floor cavity through mechanical forces imposed by return duct leakage in the floor cavity.

  18. Investigation of HV/HR-CMOS technology for the ATLAS Phase-II Strip Tracker Upgrade

    Science.gov (United States)

    Fadeyev, V.; Galloway, Z.; Grabas, H.; Grillo, A. A.; Liang, Z.; Martinez-Mckinney, F.; Seiden, A.; Volk, J.; Affolder, A.; Buckland, M.; Meng, L.; Arndt, K.; Bortoletto, D.; Huffman, T.; John, J.; McMahon, S.; Nickerson, R.; Phillips, P.; Plackett, R.; Shipsey, I.; Vigani, L.; Bates, R.; Blue, A.; Buttar, C.; Kanisauskas, K.; Maneuski, D.; Benoit, M.; Di Bello, F.; Caragiulo, P.; Dragone, A.; Grenier, P.; Kenney, C.; Rubbo, F.; Segal, J.; Su, D.; Tamma, C.; Das, D.; Dopke, J.; Turchetta, R.; Wilson, F.; Worm, S.; Ehrler, F.; Peric, I.; Gregor, I. M.; Stanitzki, M.; Hoeferkamp, M.; Seidel, S.; Hommels, L. B. A.; Kramberger, G.; Mandić, I.; Mikuž, M.; Muenstermann, D.; Wang, R.; Zhang, J.; Warren, M.; Song, W.; Xiu, Q.; Zhu, H.

    2016-09-01

    ATLAS has formed strip CMOS project to study the use of CMOS MAPS devices as silicon strip sensors for the Phase-II Strip Tracker Upgrade. This choice of sensors promises several advantages over the conventional baseline design, such as better resolution, less material in the tracking volume, and faster construction speed. At the same time, many design features of the sensors are driven by the requirement of minimizing the impact on the rest of the detector. Hence the target devices feature long pixels which are grouped to form a virtual strip with binary-encoded z position. The key performance aspects are radiation hardness compatibility with HL-LHC environment, as well as extraction of the full hit position with full-reticle readout architecture. To date, several test chips have been submitted using two different CMOS technologies. The AMS 350 nm is a high voltage CMOS process (HV-CMOS), that features the sensor bias of up to 120 V. The TowerJazz 180 nm high resistivity CMOS process (HR-CMOS) uses a high resistivity epitaxial layer to provide the depletion region on top of the substrate. We have evaluated passive pixel performance, and charge collection projections. The results strongly support the radiation tolerance of these devices to radiation dose of the HL-LHC in the strip tracker region. We also describe design features for the next chip submission that are motivated by our technology evaluation.

  19. Numerical investigation of phase change materials thermal capacitor for pipe flow

    Directory of Open Access Journals (Sweden)

    Kurnia Jundika Candra

    2017-01-01

    Full Text Available This study addresses the performance of phase change material as thermal capacitor. A computational fluid dynamics (CFD model is developed to take into account the conjugate heat transfer between water as the heat transfer fluid (HTF and PCM as thermal capacitor. A pulsating inlet temperature with constant inlet velocity is prescribed to represent temperature variation. The performance of thermal capacitor is evaluated by closely monitoring outlet temperature and comparing it with inlet temperature to examine the reduction in temperature fluctuation. To intensify heat transfer between HTF and PCM, extended surfaces (fins are installed on PCM side. The results indicate that PCM thermal capacitor can reduce temperature fluctuation by ∼ 1 °C. This reduction can be improved further when extended surface is installed with ∼ 1.5 °C reduction in temperature fluctuation is achieved. Moreover, it is found that the maximum temperature is delayed at the outlet due to slow conjugate heat transfer between HTF and PCM. Inlet velocity is found to have considerable influence of the temperature fluctuation reduction: Slower inlet velocity results in a better temperature fluctuation reduction. This study is expected to serve as a guideline in designing PCM-based thermal capacitor.

  20. Numerical and dimensional investigation of two-phase countercurrent imbibition in porous media

    KAUST Repository

    El-Amin, Mohamed

    2013-04-01

    In this paper, we introduce a numerical solution of the problem of two-phase immiscible flow in porous media. In the first part of this work, we present the general conservation laws for multiphase flows in porous media as outlined in the literature for the sake of completion where we emphasize the difficulties associated with these equations in their primitive form and the fact that they are, generally, unclosed. The second part concerns the 1D computation for dimensional and non-dimensional cases and a theoretical analysis of the problem under consideration. A time-scale based on the characteristic velocity is used to transform the macroscopic governing equations into a non-dimensional form. The resulting dimensionless governing equations involved some important dimensionless physical parameters such as Bond number Bo, capillary number Ca and Darcy number Da. Numerical experiments on the Bond number effect is performed for two cases, gravity opposing and assisting. The theoretical analysis illustrates that common formulations of the time-scale forces the coefficient Da12Ca to be equal to one, while formulation of dimensionless time based on a characteristic velocity allows the capillary and Darcy numbers to appear in the dimensionless governing equation which leads to a wide range of scales and physical properties of fluids and rocks. The results indicate that the buoyancy effects due to gravity force take place depending on the location of the open boundary. © 2012 Elsevier B.V. All rights reserved.

  1. Nonideal equilibrium dissolution of trichloroethene from a decane-based nonaqueous phase liquid mixture: Experimental and modeling investigation

    Science.gov (United States)

    McCray, John E.; Dugan, Pamela J.

    2002-07-01

    Batch equilibrium solubility studies were conducted to examine the solubilization behavior of a chlorinated solvent, trichloroethene (TCE), from a fuel-based nonaqueous phase liquid (NAPL) mixture. An alkane (n-decane) was used as a model compound because it is often a primary compound in jet fuel. The NAPL phase mole fractions of the chlorinated solvent in the mixture (XTCEN) that were investigated are typical of in situ values found at industrial and military waste sites (0.0001 >= XTCEN UNIFAC method greatly underpredicts the γTCEN in this surrogate fuel. A NAPL-mixture equilibrium-dissolution model was developed that incorporates the observed nonideal dissolution. This model indicates that nonideal NAPL dissolution is 4 times faster than ideal dissolution for a hypothetical NAPL mixture with an initial XTCEN = 0.001. The magnitude of this effect becomes more important as the initial value of the XTCEN is decreased.

  2. Model development of SAS4A and investigation on the initiating phase consequences in LMFRs related with material motion

    International Nuclear Information System (INIS)

    Niwa, H.

    1994-01-01

    This paper focuses on an analytical aspect of the initiating phase scenario and consequences of postulated core disruptive accident in liquid-metal-cooled fast breeder reactors. An analytical code, SAS4A, has been developed at Argonne National Laboratory, and introduced to PNC. Improvement and validation effort have been performed for the mixed-oxide version of SAS4A at PNC. This paper describes firstly recent development of SAS4A's material motion related models briefly. A fission gas mass transfer model and solid fuel chunk jamming model are developed and introduced to SAS4A, and validated using CABRI-2 E13 experimental data. Secondly, an investigation of the mechanism of energetics in the initiating phase of an unprotected loss-of-flow accident has identified major control parameters which are intimately related to core design parameters and material motion phenomena. (author)

  3. Phase 1 data summary report for the Clinch River Remedial Investigation: Health risk and ecological risk screening assessment

    Energy Technology Data Exchange (ETDEWEB)

    Cook, R.B.; Adams, S.M.; Beauchamp, J.J.; Bevelhimer, M.S.; Blaylock, B.G.; Brandt, C.C.; Ford, C.J.; Frank, M.L.; Gentry, M.J.; Holladay, S.K.; Hook, L.A.; Levine, D.A.; Longman, R.C.; McGinn, C.W.; Skiles, J.L.; Suter, G.W.; Williams, L.F.

    1992-12-01

    The Clinch River Remedial Investigation (CRRI) is designed to address the transport, fate, and distribution of waterborne contaminants released from the US Department of Energy's (DOE's) Oak Ridge Reservation (ORR) and to assess potential risks to human health and the environment associated with these contaminants. The contaminants released since the early 1940s include a variety of radionuclides, metals, and organic compounds. The purpose of this report is to summarize the results of Phase 1 of the CRRI. Phase 1 was designed to (1) obtain high-quality data to confirm existing historical data for contaminant levels in fish, sediment, and water from the CR/WBR; (2) determine the in the range of contaminant concentrations present river-reservoir system; (3) identify specific contaminants of concern; and (4) establish the reference (background) concentrations for those contaminants.

  4. Investigation and thermodynamic calculation of phase diagram of CdI2-PbI2-NaI system

    International Nuclear Information System (INIS)

    Storonkin, A.V.; Vasil'kova, I.V.; Korobkov, S.V.

    1976-01-01

    Using the thermographic and X-ray phase analyses binary CdI 2 -PbI 2 , PI 2 -NaI, CdI 2 -NaI systems and a triple CdI 2 -PbI 2 -NaI system are investigated and their melting diagrams are plotted. A method of thermodynamic calculation has been proposed and tested of the shape of the eutectic lines for the system CdI 2 -PbI 2 -NaI, taking into account the non-ideality of the liquid phase. The method uses data obtained for the binary systems. The liquidus surface of the triple system has been constructed on the basis of the calculation. The results of the calculation of the triple eutectics are in good agreement with the experimental data

  5. Investigation of phase-wise voltage regulator control logics for compensating voltage deviations in an experimental low voltage network

    DEFF Research Database (Denmark)

    Hu, Junjie; Zecchino, Antonio; Marinelli, Mattia

    2016-01-01

    This paper investigates the control logics of an on-load tap-changer (OLTC) transformer by means of an experimental system validation. The experimental low-voltage unbalanced system consists of a decoupled single-phase OLTC transformer, a 75-metre 16 mm2 cable, a controllable single-phase resistive...... load and an electric vehicle, which has the vehicle-to-grid function. Three control logics of the OLTC transformer are described in the study. The three control logics are classified based on their control objectives and control inputs, which include network currents and voltages, and can be measured...... either locally or remotely. To evaluate and compare the control performances of the three control logics, all the tests use the same loading profiles. The experimental results indicate that the modified line compensation control can regulate voltage in a safe band in the case of various load...

  6. Investigation of environmental friendly Te-free SiSb material for applications of phase-change memory

    International Nuclear Information System (INIS)

    Zhang Ting; Song Zhitang; Liu Bo; Feng Songlin

    2008-01-01

    Te-free environmental friendly Si x Sb 100−x phase-change materials are investigated. The binary material, which is compatible with the complementary metal-oxide-semiconductor manufacturing process, is outstanding in various properties. Si x Sb 100−x shows a much better data retention as compared with Ge 2 Sb 2 Te 5 . The density change for Si 10 Sb 90 and Si 16 Sb 84 is only about 3% and 3.8%, respectively. The failure times for Si 10 Sb 90 and Si 16 Sb 84 are about 10 3 and 10 6 times longer than that of Ge 2 Sb 2 Te 5 at 110 °C. The crystallization temperature of Si x Sb 100−x increases with silicon content within the material. Si x Sb 100−x materials are good candidates for the phase-change memory applications

  7. Structure and property investigations of TDO in aqueous phase by density functional theory, UV absorption, and Raman spectroscopy.

    Science.gov (United States)

    Shao, Jianzhong; Liu, Xiaoyun; Chen, Pin; Wu, Qiuxia; Zheng, Xuming; Pei, Kemei

    2014-05-01

    Density functional theory, UV absorption, and Raman spectroscopy are used to investigate the structure and properties of TDO in aqueous solution. The equilibrium structures, UV absorption spectra, interaction energies, and Raman spectroscopy data of TDO, AIMSA, and 12 TDO or AIMSA clusters are calculated. Raman spectroscopy experiments are carried out by 488 and 208 nm laser excitation. The Raman spectra of TDO in solid and aqueous phases have been compared, and the most possible structure for TDO in aqueous phase was deduced from analysis of the DFT calculations for the examined models, the experimental UV absorption spectrum, and Raman spectra of TDO. The interaction energy results show that TDO's solubility in water is originated from the TDO-water cyclic oligomer. The calculated UV absorption and Raman spectra of the I2·2H2O-cyc cluster model agree with the experimental results of TDO in aqueous solution very well.

  8. Investigation on a Novel Discontinuous Pulse-Width Modulation Algorithm for Single-phase Voltage Source Rectifier

    DEFF Research Database (Denmark)

    Qu, Hao; Yang, Xijun; Guo, Yougui

    2014-01-01

    Single-phase voltage source converter (VSC) is an important power electronic converter (PEC), including single-phase voltage source inverter (VSI), single-phase voltage source rectifier (VSR), single-phase active power filter (APF) and single-phase grid-connection inverter (GCI). Single-phase VSC...

  9. Investigation of Two-Phase Flow in AxialCentrifugal Impeller by Hydrodynamic Modeling Methods

    Directory of Open Access Journals (Sweden)

    V. O. Lomakin

    2014-01-01

    Full Text Available The article provides a methodology to study the flow in the wet part of the pump with fundamentally new axial-centrifugal impeller by methods of hydrodynamic modeling in the software package STAR CCM +. The objective of the study was to determine the normal and cavitation characteristics of the pump with a new type of wet part, as well as optimization of the geometrical parameters of the pump. Authors solved this problem using an example of the hot coolant pump, which should meet high requirements for cavitation quality and efficiency (hydraulic efficiency up to 87%, critical value of NPSH to 2.2 m.Also, the article focuses on the methods of numerical solution of two-phase flow simulation in a pump that are needed for a more accurate simulation of cavitation in the pump and research work in liquids with high gas content.Hydrodynamic modeling was performed on a computing cluster at the department E-10 of BMSTU for pump flow simulation in unsteady statement of problem using the computational grid size to 1.5 million cells. Simultaneously, the experimental model of the pump was made by 3D printing and tested at the stand in the BMSTU. Test results, which were compared with the calculated data are also given in the article. Inaccuracy of the calculation of pump head does not exceed 5%.The simulation results may be of interest to specialists in the field of hydrodynamic modeling, and for designers of such pumps. The authors also report production of a full-length prototype of the pump in order to conduct further testing for the verification of the data in the article, primarily in terms of cavitation characteristics.

  10. Experimental and computational investigation on the gas phase reaction of p-cymene with Cl atoms.

    Science.gov (United States)

    Dash, Manas Ranjan; Srinivasulu, G; Rajakumar, B

    2015-01-29

    The rate coefficient for the gas-phase reaction of Cl atoms with p-cymene was determined as a function of temperature (288-350 K) and pressure (700-800 Torr) using the relative rate technique, with 1,3-butadiene and ethylene as reference compounds. Cl atoms were generated by UV photolysis of oxalyl chloride ((COCl)2) at 254 nm, and nitrogen was used as the diluent gas. The rate coefficient for the reaction of Cl atoms with p-cymene at 298 K was measured to be (2.58 ± 1.55) × 10(-10) cm(3) molecule(-1) s(-1). The kinetic data obtained over the temperature range 288-350 K were used to derive an Arrhenius expression: k(T) = (9.36 ± 2.90) × 10(-10) exp[-(488 ± 98)/T] cm(3) molecule(-1) s(-1). Theoretical kinetic calculations were also performed for the title reaction using canonical variational transition state theory (CVT) with small curvature tunneling (SCT) between 250 and 400 K. The calculated rate coefficients obtained over the temperature range 250-400 K were used to derive an Arrhenius expression: k(T) = 5.41 × 10(-13) exp[1837/T] cm(3) molecule(-1) s(-1). Theoretical study indicated that addition channels contribute maximum to the total reaction and H-abstraction channels can be neglected. The atmospheric lifetime (τ) of p-cymene due to its reactions with various tropospheric oxidants was estimated, and it was concluded that the reactions of p-cymene with Cl atoms may compete with OH radicals in the marine boundary layer and in coastal urban areas where the concentration of Cl atoms is high.

  11. Experimental investigations on the performance of a collector–storage wall system using phase change materials

    International Nuclear Information System (INIS)

    Zhou, Guobing; Pang, Mengmeng

    2015-01-01

    Highlights: • Performance of collector–storage wall using PCM was experimentally studied. • PCM surface temperature rises steep–slow–steep successively during charge. • After sharp drops, PCM surface temperature decreases slightly during discharge. • Temperatures of gap air, glazing and room vary with PCM surface temperature. • Air flow rate and heating rate fluctuate during charge but go steady after discharge. - Abstract: Experiments have been performed on the thermal behavior of a collector–storage wall system using PCM (phase change material). PCM slabs were attached on the gap-side wall surface to increase the heat storage. The test was carried out for a whole day with charging period of 6.5 h and discharging period of 17.5 h, respectively. Wall and air temperatures as well as air velocity in the gap were measured for analysis. The results showed that the PCM surface temperature increases first rapidly, then slowly and rapidly again during the charging process, which in turn corresponds with the three storage stages: sensible heat (solid), latent heat (melting) and sensible heat (liquid), respectively; while in the discharging process the PCM surface temperature decreases slightly shortly after the initial sharp drops, which suggests the long time period of solidification for PCM to release latent heat. Subject to the variations of PCM surface temperatures, similar trends were also found for the gap air temperatures, glazing temperature and indoor temperature. Both the air flow rate and heating rate by air circulation have up and down fluctuations during the charging period, and then, shortly after initial sharp drops, they keep at nearly steady values during the discharging period. The indoor temperature was found to be above 22 °C during the whole discharging period (17.5 h) under present conditions, which indicates that the indoor thermal comfort could be kept for a long time by using PCM in collector–storage wall system.

  12. Gas phase anion photoelectron spectroscopy and theoretical investigation of gold acetylide species

    Science.gov (United States)

    Wang, Peng; Zhang, Wenjing; Xu, Xi-Ling; Yuan, Jinyun; Xu, Hong-Guang; Zheng, Weijun

    2017-05-01

    We conducted gas phase anion photoelectron spectroscopy and density functional theory studies on a number of gold acetylide species, such as AuC2H, AuC2Au, and Au2C2H. Based on the photoelectron spectra, the electron affinities of AuC2H, AuC2Au, and Au2C2H are measured to be 1.54(±0.04), 1.60(±0.08), and 4.23(±0.08) eV, respectively. The highest occupied molecular orbital-lowest unoccupied molecular orbital (HOMO-LUMO) gaps of AuC2H and AuC2Au are measured to be about 2.62 and 2.48 eV, respectively. It is interesting that photoelectron spectra of AuC2H- and AuC2Au- display similar spectral features. The comparison of experimental and theoretical results confirms that the ground-state structures of AuC2H-, AuC2Au-, and their neutrals are all linear with Au—C≡C—H and Au—C≡C—Au configurations. The similar geometric structures, spectral features, HOMO-LUMO gaps, and chemical bonding between AuC2H-/0 and AuC2Au-/0 demonstrate that Au atom behaves like H atom in these species. The photoelectron spectrum of Au2C2H- shows that Au2C2H has a high electron affinity of 4.23(±0.08) eV, indicating Au2C2H is a superhalogen. Further, we found an unusual similarity between the terminal Au atom of Au2C2H- and the iodine atom of IAuC2H-.

  13. Preliminary investigations of equilibrium reconstruction quality during ELMy and ELM-free phases on JET

    Energy Technology Data Exchange (ETDEWEB)

    Gelfusa, M., E-mail: gelfusa@ing.uniroma2.it [Associazione EURATOM-ENEA—University of Rome “Tor Vergata”, Rome (Italy); Murari, A. [Associazione EURATOM-ENEA per la Fusione, Consorzio RFX, 4-35127 Padova (Italy); Peluso, E. [Associazione EURATOM-ENEA sulla Fusione, ENEA C.R. Frascati, C.P. 65, I-00044 Frascati, Rome (Italy); Gaudio, P. [Associazione EURATOM-ENEA—University of Rome “Tor Vergata”, Rome (Italy); Orsitto, F.P. [Associazione EURATOM-ENEA sulla Fusione, ENEA C.R. Frascati, C.P. 65, I-00044 Frascati, Rome (Italy); Gerasimov, S. [EURATOM/CCFE Fusion Association, Culham Science Centre, Abingdon, Oxon OX14 3DB (United Kingdom); Collaboration: JET-EFDA Contributors

    2013-08-21

    On JET, the magnetic topology is normally derived from the code EFIT, which solves the Grad–Shafranov equation with constraints imposed by the available measurements, typically the pick-up coils. Both the code and the measurements are expected to perform worse during ELMs. To assess this hypothesis, various statistical indicators, based on the values of the residuals and their probability distribution, have been calculated. They all show that the quality of EFIT reconstructions is clearly better in absence of ELMs. How the responsibility, for the lower quality of the reconstructions, is shared between the measurements and EFIT is a subject under investigation. © 2001 Elsevier Science. All rights reserved.

  14. Nevada Nuclear Waste Storage Investigations: exploratory shaft. Phase I. Conceptual design report

    International Nuclear Information System (INIS)

    Nelson, D.C.; Merson, T.J.; McGuire, P.L.; Sibbitt, W.L.

    1982-06-01

    It is proposed that an Exploratory Shaft (ES) be constructed in Yucca Mountain on or near the southwest portion of the Nevada Test Site (NTS) as part of the Nevada Nuclear Waste Storage Investigations. This document describes a conceptual design for an ES and a cost estimate based on a set of construction assumptions. Included in this document are appendixes consisting of supporting studies done at NTS by Fenix and Scisson, Inc. and Holmes and Narver, Inc. These appendixes constitute a history of the development of the design and are included as part of the record

  15. Investigation of the phase relations in the U-Al-Ge ternary system: Influence of the Al/Ge substitution on the properties of the intermediate phases

    Energy Technology Data Exchange (ETDEWEB)

    Moussa, C.; El Sayah, Z. [Institut des Sciences Chimiques de Rennes, Chimie du Solide et Matériaux, UMR CNRS 6226, Université Rennes 1, Campus de Beaulieu, 35042 Rennes Cedex (France); Chajewski, G. [Institute of Low Temperature and Structure Research, Polish Academy of Sciences, ul. Okólna 2, 50-422 Wrocław (Poland); Berche, A.; Dorcet, V. [Institut des Sciences Chimiques de Rennes, Chimie du Solide et Matériaux, UMR CNRS 6226, Université Rennes 1, Campus de Beaulieu, 35042 Rennes Cedex (France); Pikul, A.P. [Institute of Low Temperature and Structure Research, Polish Academy of Sciences, ul. Okólna 2, 50-422 Wrocław (Poland); Pasturel, M. [Institut des Sciences Chimiques de Rennes, Chimie du Solide et Matériaux, UMR CNRS 6226, Université Rennes 1, Campus de Beaulieu, 35042 Rennes Cedex (France); Joanny, L. [ScanMAT – CMEBA, University of Rennes 1, Campus de Beaulieu, 35042 Rennes Cedex (France); Stepnik, B. [AREVA/CERCA, 10 Rue Juliette Récamier, 69006 Lyon (France); Tougait, O., E-mail: tougait@univ-rennes1.fr [Institut des Sciences Chimiques de Rennes, Chimie du Solide et Matériaux, UMR CNRS 6226, Université Rennes 1, Campus de Beaulieu, 35042 Rennes Cedex (France); Unité de Catalyse et de Chimie du Solide, UMR CNRS 8181, Université de Lille, 59695 Villeneuve d' Ascq (France)

    2016-11-15

    below the solidus. A unique ternary phase showing a large homogeneity domain, U{sub 3}Al{sub 2−x}Ge{sub 3+x} for −0.1≤x≤1.35 and −0.2≤x≤1.5 at 673 K and 1173 K respectively has been evidenced. It is best described with the non-centrosymmetric space group I4cm above room temperature. A linear increase of the ferromagnetic ordering is observed with the Al content. - Highlights: • Isothermal sections of the U-Al-Ge system were investigated for 673 K and 1173 K. • An isomorphous solid-solution UAl{sub 3}-UGe{sub 3} forms for the whole composition range. • U{sub 3}Al{sub 2−x}Ge{sub 3+x} the unique ternary phase to form exists for a large homogeneity domain. • U{sub 3}Al{sub 2−x}Ge{sub 3+x} is best described in I4cm space group above room temperature. • The ferromagnetic transition of U{sub 3}Al{sub 2−x}Ge{sub 3+x} linearly increases with the Al content.

  16. Phase I remedial investigation report for the 300-FF-5 operable unit, Volume 1

    International Nuclear Information System (INIS)

    1994-01-01

    The focus of this remedial investigation (RI) is the 300-FF-5 operable unit, one of five operable units associated with the 300 Area aggregate of the U.S. Department of Energy's (DOE's) Hanford Site. The 300-FF-5 operable unit is a groundwater operable unit beneath the 300-FF-1, 300-FF-2, and 300-FF-3 source operable units. This operable unit was designated to include all contamination detected in the groundwater and sediments below the water table that emanates from the 300-FF-1, 300-FF-2, and 300-FF-3 operable units (DOE-RL 1990a). In November 1989, the U.S. Environmental Protection Agency (EPA) placed the 300 Area on the National Priorities List (NPL) contained within Appendix B of the National Oil and Hazardous Substance Pollution Contingency Plan (NCP, 53 FR 51391 et seq.). The EPA took this action pursuant to their authority under the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA, 42 USC 9601 et seq.). The DOE Richland Operations Office (DOE-RL), the EPA and Washington Department of Ecology (Ecology) issued the Hanford Federal Facility Agreement and Consent Order (Tri-Party Agreement), in May 1989 (Ecology et al. 1992, Rev. 2). This agreement, among other matters, governs all CERCLA efforts at the Hanford Site. In June 1990, a remedial investigation/feasibility study (RI/FS) workplan for the 300-FF-5 operable unit was issued pursuant to the Tri-Party Agreement

  17. Phase I remedial investigation report for the 300-FF-5 operable unit, Volume 1

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-01-01

    The focus of this remedial investigation (RI) is the 300-FF-5 operable unit, one of five operable units associated with the 300 Area aggregate of the U.S. Department of Energy`s (DOE`s) Hanford Site. The 300-FF-5 operable unit is a groundwater operable unit beneath the 300-FF-1, 300-FF-2, and 300-FF-3 source operable units. This operable unit was designated to include all contamination detected in the groundwater and sediments below the water table that emanates from the 300-FF-1, 300-FF-2, and 300-FF-3 operable units (DOE-RL 1990a). In November 1989, the U.S. Environmental Protection Agency (EPA) placed the 300 Area on the National Priorities List (NPL) contained within Appendix B of the National Oil and Hazardous Substance Pollution Contingency Plan (NCP, 53 FR 51391 et seq.). The EPA took this action pursuant to their authority under the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA, 42 USC 9601 et seq.). The DOE Richland Operations Office (DOE-RL), the EPA and Washington Department of Ecology (Ecology) issued the Hanford Federal Facility Agreement and Consent Order (Tri-Party Agreement), in May 1989 (Ecology et al. 1992, Rev. 2). This agreement, among other matters, governs all CERCLA efforts at the Hanford Site. In June 1990, a remedial investigation/feasibility study (RI/FS) workplan for the 300-FF-5 operable unit was issued pursuant to the Tri-Party Agreement.

  18. Investigation of ractopamine-imprinted polymer for dispersive solid-phase extraction of trace beta-agonists in pig tissues.

    Science.gov (United States)

    Hu, Yuling; Liu, Ruijin; Li, Yuanwen; Li, Gongke

    2010-07-01

    Ractopamine, as an alternative beta-agonist to clenbuterol, is more and more used as leanness-enhancing agent in the swine industry. This work presents a new molecularly imprinted polymer (MIP) using ractopamine as template for dispersive solid-phase extraction of trace ractopamine and the structural related beta-agonists in animal tissues. The binding properties and selectivity of MIP were investigated. High selectivity in polar environment was found, since the extraction capacity of ractopamine with the MIP was 4.5-fold as much as that with the non-imprinted polymer in acetonitrile. Cross-selectivity investigation indicates that the MIP preferentially binds the template and then the structural analogues according to their molecular similarity. Thermodynamic and kinetic investigation was performed to interpret the specific adsorption and molecular recognition of the MIP for ractopamine. Standard free energy, standard enthalpy, and standard entropy were determined. Related information suggested that adsorption of ractopamine onto MIP was an exothermic, spontaneous process. The MIP can be applied as dispersive solid-phase extraction material for enrichment of ractopamine, isoxsuprine, fenoterol and clenbuterol in complex samples before HPLC analysis. The method revealed detection limits of 0.20-0.90 microg/L, recoveries of 83.8-115.2 and 85.2-110.2% for the spiked pig muscle and pig liver, respectively, with the RSD from 2.5 to 8.8%.

  19. Distribution of cesium between colloid-rock phases-establishment of experimental system and investigation of Cs distribution between colloid and rock

    International Nuclear Information System (INIS)

    Nakata, Kotaro

    2006-01-01

    Distribution and re-distribution of cesium between 3-phases (colloid, rock and water) was investigated. Analcite and bentonite colloid ware used as colloid phase and muscovite was used as rock phase. Before investigating the distribution between 3-phases, sorption and desorption behavior of Cs on analcite colloid, bentonite colloid and muscovite was investigated. It was found some fraction of Cs sorbed irreversibly on analcite colloid, while Cs sorbed reversibly on bentonite colloid. The experimental system was established for assessment of the distribution of nuclides between 3-phases by using combination of membrane filter and experimental cell. Since colloid and muscovite were separated by membrane filter, sorption of colloid on muscovite could be prevented and we could obtain distribution of Cs as ion. The distribution of Cs between 3-phases were obtained by this experimental system. Furthermore, re-distribution experiment was also carried out by using this system. After 7 days contact of colloid with Cs, distribution of sorbed Cs on colloid to liquid or muscovite phase was investigated. Comparing sorption and desorption isotherm with the distribution of Cs between 3-phases, it was found that Kd value of colloid (ratio of Cs concentration in liquid phase to amount of sorbed Cs on colloid phase) estimated in 2-phases (water and colloid) is different from that in 3-phases. Furthermore, in the case of analcite colloid, Kd value of colloid obtained in 3-phases distribution experiment was different from that obtained in re-distribution experiment. This is considered because of the irreversibility of Cs sorption on analcite colloid. Thus, it was found distribution of Cs in 3-phases was not predictable from sorption and desorption isotherm or Kd value of 2-phases (water-rock, water-colloid). (author)

  20. Experimental and numerical investigation of shock wave propagation through complex geometry, gas continuous, two-phase media

    International Nuclear Information System (INIS)

    Liu, J. Chien-Chih

    1993-01-01

    The work presented here investigates the phenomenon of shock wave propagation in gas continuous, two-phase media. The motivation for this work stems from the need to understand blast venting consequences in the HYLIFE inertial confinement fusion (ICF) reactor. The HYLIFE concept utilizes lasers or heavy ion beams to rapidly heat and compress D-T targets injected into the center of a reactor chamber. A segmented blanket of failing molten lithium or Li 2 BeF 4 (Flibe) jets encircles the reactors central cavity, shielding the reactor structure from radiation damage, absorbing the fusion energy, and breeding more tritium fuel

  1. Experimental investigation of two-phase gas-liquid flow in microchannel with T-junction

    Science.gov (United States)

    Bartkus, German; Kozulin, Igor; Kuznetsov, Vladimir

    2017-10-01

    Using high-speed video recording and the method of dual laser scanning the gas-liquid flow was investigated in rectangular microchannels with an aspect ratio of 2.35 and 1.26. Experiments were earned out for the vertical flow of ethanol-nitrogen mixture in a microchannel with a cross section of 553×235 µm and for the horizontal flow of water-nitrogen mixture in a microchannel with a cross section of 315×250 µm. The T-mixer was used at the channel's inlet for gas-liquid flow formation. It was observed that elongated bubble, transition, and annular flows are the main regimes for a microchannel with a hydraulic diameter substantially less than the capillary constant. Using laser scanning, the maps of flow regimes for ethanol-nitrogen and water-nitrogen mixtures were obtained and discussed.

  2. Investigation on stacked cascade multilevel inverter by employing single-phase transformers

    Directory of Open Access Journals (Sweden)

    Y. Suresh

    2016-06-01

    Full Text Available In the present paper a new version of multilevel inverter is investigated. This new version is based on hybrid association of commutation cells with H-bridge cells. The association allows a significant reduction of the volume of the capacitors. In fact, presented topology allows us to work on higher input voltage levels with the same power switches. This new version is generally called as SCMI (stacked cascade multilevel inverter. The proposed inverter has potential to generate high quality waveforms, reduction in switching frequency, capable to operate at higher voltage levels and finally utilizes minimum number of switching components. The presented version of SCMI is simulated in Matlab-simulink and further, experimental validation is carried out in the laboratory with prototype setup.

  3. Experimental investigation of single-phase flow friction in narrow annuli

    International Nuclear Information System (INIS)

    Sun Zhongning; Sun Licheng; Yan Changqi; Huang Weitang

    2004-01-01

    Experimental investigations of water flow friction in horizontal narrow annuli, with gap sizes of 0.57-3.08 mm, were carried out. The tests involved both laminar and turbulent flow regimes. The critical Reynolds number transited from laminar flow to turbulent flow was examed and observed. The friction factors obtained from experiments were compared with conventional correlations evaluated results, and the influences of channel scale and eccentricity on flow friction characteristics were discussed. It was found that fluid friction in turbulent regime could be predicted by conventional correlations with satisfied degree, but both values and varying trend of that vs. r i /r o in laminar regime were obviously departure from theoretically results when the gap sizes were less than 2.0 mm, and the critical Reynolds number was slightly less then 2300 when the gap sizes were less than 1.0 mm

  4. Flow characteristics of centrifugal gas-liquid separator. Investigation with air-water two-phase flow experiment

    International Nuclear Information System (INIS)

    Yoneda, Kimitoshi; Inada, Fumio

    2004-01-01

    Air-water two-phase flow experiment was conducted to examine the basic flow characteristics of a centrifugal gas-liquid separator. Vertical transparent test section, which is 4 m in height, was used to imitate the scale of a BWR separator. Flow rate conditions of gas and liquid were fixed at 0.1 m 3 /s and 0.033 m 3 /s, respectively. Radial distributions of two-phase flow characteristics, such as void fraction, gas velocity and bubble chord length, were measured by traversing dual optical void probes in the test section, horizontally. The flow in the standpipe reached to quasi-developed state within the height-to-diameter aspect ratio H/D=10, which in turn can mean the maximum value for an ideal height design of a standpipe. The liquid film in the barrel showed a maximum thickness at 0.5 to 1 m in height from the swirler exit, which was a common result for three different standpipe length conditions, qualitatively and quantitatively. The empirical database obtained in this study would contribute practically to the validation of numerical analyses for an actual separator in a plant, and would also be academically useful for further investigations of two-phase flow in large-diameter pipes. (author)

  5. Single-crystal X-ray and neutron powder diffraction investigation of the phase transition in tetrachlorobenzene.

    Science.gov (United States)

    Barnett, Sarah A; Broder, Charlotte K; Shankland, Kenneth; David, William I F; Ibberson, Richard M; Tocher, Derek A

    2006-04-01

    The polymorphic phase transition of 1,2,4,5-tetrachlorobenzene (TCB) has been investigated using neutron powder diffraction and single-crystal X-ray diffraction. The diffraction experiments show a reversible phase change that occurs as a function of temperature with no apparent loss of sample quality on transition between the two phases. Neutron powder diffraction gives detailed information on the molecular structural changes and lattice parameters from 2 K to room temperature. The structure of the low-temperature form has been elucidated for the first time using single-crystal X-ray diffraction. Comparison of the alpha and beta structures show that they are both based on the same sheet motif, with the differences between the two being very subtle, except in terms of crystal symmetry. Detailed analysis of the structures revealed the changes required for inter-conversion. A computational polymorph search showed that these two sheet structures are more thermodynamically stable than alternative herringbone-type structures.

  6. Experimental investigation of an indirect solar dryer integrated with phase change material for drying valeriana jatamansi (medicinal herb

    Directory of Open Access Journals (Sweden)

    A.K. Bhardwaj

    2017-09-01

    Full Text Available In this study, an experimental investigation of an indirect solar dryer integrated with phase change material has been carried out for drying Valeriana Jatamansi. The experimentation has been performed under the climatic conditions of Himalayan region, Solan (latitude − 30.91°N, longitude − 77.09°E, Himachal Pradesh (India in the month of October-November 2016. Paraffin RT-42 has been used as a phase change material in the dryer. Using this system, the moisture content of rhizomes reduced from 89% to 9% in 5 days as compared to heat pump drying and shade drying, which took 8 days and 14 days, respectively. Results of present study infer that the drying time using phase change material in this setup has reduced by 37.50% and 64.29% when compared to heat pump drying and shade drying, respectively. The dried rhizomes obtained are of superior quality in terms of colour, texture, aroma and bio-medical constituents. Analyses show that by using present setup, total valepotriates obtained were 3.47% as compared to traditional shade drying which yield 3.31%.

  7. Geological data acquisition for site characterisation at Olkiluoto: a framework for the phase of underground investigations

    International Nuclear Information System (INIS)

    Milnes, A.G.; Aaltonen, I.; Kemppainen, K.; Mattila, J.; Wikstroem, L.; Front, K.; Kaerki, A.; Gehoer, S.; Paulamaeki, S.; Paananen, M.; Ahokas, T.

    2007-05-01

    'Geological data acquisition' is a general term for the collection of observations and measurements by direct observation of exposed bedrock in the field (i.e. in natural outcrops and trenches, in drillholes, and in tunnels and other underground excavations). Only field-based data acquisition is included in this report: laboratory-based investigations will be continued, based on the field data and sampling, and all the data will be subject to discipline-specific processing, as the project proceeds. The ultimate aim of geological data acquisition is to provide the necessary data base for geological models of the bedrock of the Olkiluoto site, in connection with the construction of an underground rock characterisation facility, ONKALO, and a repository for spent nuclear fuel, at about 500m depth. Geological data acquisition plays a central role in site characterisation and modelling, and is intended to provide a solid platform on which the other disciplines (rock mechanics, hydrogeology, seismic risk assessment, etc.) can base their investigations. Based on consideration of a series of guidelines (e.g. modelling scale, source of data, level of investigation, national and international experience, special conditions at Olkiluoto, need for process understanding), a project-oriented 'framework' has been developed as a background to the different projects within the geological data acquisition programme. Each project will require its own system of data acquisition (methodology, spreadsheets, protocols, etc.), as described in the corresponding reports; the present report concentrates on the general principles which lie behind the different methodologies and data sheets. These principles are treated under three main headings: characterization of intact rock, characterization of deformation zone intersections, and characterization of individual fractures. Geological mapping of natural outcrops and trenches at Olkiluoto, and lithological logging of more than 40 rock cores

  8. Investigation and modification of the structural-phase state of oxide films on Zirconium alloys

    International Nuclear Information System (INIS)

    Volkov, N.; Kalin, B.; Osipov, V.; Markelov, V.; Pimenov, Y.

    2009-01-01

    In this work, ion mixing under irradiation by a beam of Ar + ions with a wide energy spectrum of a preliminarily applied multilayer (Al+Fe+Mo+Y) film on the substrate of Zirconium alloys has been chosen as a method of RBA with the purpose to increase the operational properties of Zirconium alloys E110 and E635. The use of Ar + ion beams with a wide energy spectrum also makes it possible to perform purification and ion polishing of the surface (in this case the surface roughness R α decreases from 1-2 to 0.2-0.4 μm) which are necessary before application of multilayer films. The state of ion-alloyed layers of alloys and oxide films on their surface after corrosion tests during up to 3000 h in a water-steam medium at the temperature of 350 0 C and the pressure of 17 MPa has been investigated in this work. Regularities of penetration of oxygen and hydrogen atoms into ion-alloyed (modified) surface layers of alloys E110 and E635 during the oxidation have been also studied

  9. Experimental investigation on the transient one phase flow through perforated plates

    International Nuclear Information System (INIS)

    Casadei, F.; Dalle Donne, M.

    1982-01-01

    The coolant flow across the perforated dip-plate during a HCDA in a LMFBR was simulated in a one-dimensional model. Several experiments with water as fluid and with various perforation ratios of the dip-plate and different initial heights of the fluid head over the dip-plate were run. The pressure drop across the dip-plate and the forces acting on the dip-plate and on the upper plug of the reactor vessel were measured in a wide range of the Reynolds and Strouhal numbers. The flow pattern downstreams the perforated plate was filmed with high-speed cameras. The resistance coefficients for the transient flow of the coolant through the perforated plate were obtained as a function of the acceleration. The forces acting on the upper plug and their time integral were compared with those acting on the dip-plate. Finally, using high-speed film pictures the formation of fluid jets downstream the dip-plate was investigated

  10. Predicting enrollment performance of investigational centers in phase III multi-center clinical trials

    Directory of Open Access Journals (Sweden)

    Rutger M. van den Bor

    2017-09-01

    Full Text Available Failure to meet subject recruitment targets in clinical trials continues to be a widespread problem with potentially serious scientific, logistical, financial and ethical consequences. On the operational level, enrollment-related issues may be mitigated by careful site selection and by allocating monitoring or training resources proportionally to the anticipated risk of poor enrollment. Such procedures require estimates of the expected recruitment performance that are sufficiently reliable to allow centers to be sensibly categorized. In this study, we investigate whether information obtained from feasibility questionnaires can potentially be used to predict which centers will and which centers will not meet their enrollment targets by means of multivariable logistic regression analysis. From a large set of 59 candidate predictors, we determined the subset that is optimal for predictive purposes using Least Absolute Shrinkage and Selection Operator (LASSO regularization. Although the extent to which the results are generalizable remains to be determined, they indicate that the prediction accuracy of the optimal model is only a marginal improvement over the intercept-only model, illustrating the difficulty of prediction in this setting.

  11. Investigation of two-phase flow instability under SMART-P core conditions

    International Nuclear Information System (INIS)

    Hwang, Dae Hyun; Lee, Chung Chan

    2005-01-01

    An integral-type advanced light water reactor, named SMART-P, is being continuously studied at KAERI. The reactor core consists of hundreds of closed-channel type fuel assemblies with vertical upward flows. The upper and lower parts of the fuel assembly channels are connected to the common heads. The constant pressure drop imposed on the channel is responsible for the occurrence of density wave oscillations under local boiling and/or natural circulation conditions. The fuel assembly channel with oscillatory flow is highly susceptible to experience the CHF which may cause the fuel failure due to a sudden increase of the cladding temperature. Thus, prevention of the flow instability is an important criterion for the SMART-P core design. Experimental and analytical studies have been conducted in order to investigate the onset of flow instability (OFI) under SMART core conditions. The parallel channel oscillations were observed in a high pressure water-loop test facility. A linear stability analysis model in the frequency-domain was developed for the prediction of the marginal stability boundary (MSB) in the parallel boiling channels

  12. Investigating excitation-dependent and fringe-field effects of electromagnet and permanent-magnet phase shifters for a crossed undulator

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Ting-Yi, E-mail: chung.albert@nsrrc.org.tw [National Synchrotron Radiation Research Center, Hsinchu Science Park, Hsinchu 30076, Taiwan (China); Yang, Chih-Sheng; Chu, Yun-Liang; Lin, Fu-Yuan; Jan, Jyh-Chyuan [National Synchrotron Radiation Research Center, Hsinchu Science Park, Hsinchu 30076, Taiwan (China); Hwang, Ching-Shiang [National Synchrotron Radiation Research Center, Hsinchu Science Park, Hsinchu 30076, Taiwan (China); Department of Electrophysics, National Chiao Tung University, Hsinchu 30050, Taiwan (China)

    2017-04-01

    To enhance the flux density or to control polarization, a phase shifter was designed and used to modulate the phase matching between segmented undulators. A larger hysteresis loop causes, however, a repeatability issue in the phase matching; the fringe field of the phase shifter creates an extra magnetic-field error. The design of the phase shifter must therefore minimize the hysteresis loop and fringe field to maintain the phases exact and to ignore the crosstalk effect. Two critical issues are the hysteresis-loop problem and the fringe-field effect, which determine the radiation performance and the stability of the ring. To investigate these issues, a phase shifter was constructed to operate in accordance with electromagnetic- and permanent-type magnets; the results from the field measurements and shims are discussed here. The shimming algorithm and a compact permanent-magnet phase shifter that eliminates the issues are also presented.

  13. Phase Identification of Nanometric Precipitates in Al-Si-Cu Aluminum Alloy by Hr-Stem Investigations

    Directory of Open Access Journals (Sweden)

    Pawlyta M.

    2016-09-01

    Full Text Available Aluminium recycling is cost-effective and beneficial for the environment. It is expected that this trend will continue in the future, and even will steadily increase. The consequence of the use of recycled materials is variable and difficult to predict chemical composition. This causes a significant reduction in the production process, since the properties of produced alloy are determined by the microstructure and the presence of precipitates of other phases. For this reason, the type and order of formation of precipitates were systematically investigated in recent decades. These studies involved, however, only the main systems (Al-Cu, Al-Mg-Si, Al-Cu-Mg, Al-Mg-Si-Cu, while more complex systems were not analysed. Even trace amounts of additional elements can significantly affect the alloy microstructure and composition of precipitates formed. This fact is particularly important in the case of new technologies such as laser surface treatment. As a result of extremely high temperature and temperature changes after the laser remelting large amount of precipitates are observed. Precipitates are nanometric in size and have different morphology and chemical composition. A full understanding of the processes that occur during the laser remelting requires their precise but also time effectively phase identification, which due to the diversity and nanometric size, is a major research challenge. This work presents the methodology of identification of nanometer phase precipitates in the alloy AlSi9Cu, based on the simultaneous TEM imaging and chemical composition analysis using the dispersion spectroscopy using the characteristic X-ray. Verification is performed by comparing the simulation unit cell of the identified phase with the experimental high-resolution image.

  14. Theoretical investigations on two-phase flow instability in parallel channels under axial non-uniform heating

    International Nuclear Information System (INIS)

    Lu, Xiaodong; Wu, Yingwei; Zhou, Linglan; Tian, Wenxi; Su, Guanghui; Qiu, Suizheng; Zhang, Hong

    2014-01-01

    Highlights: • We developed a model based on homogeneous flow model to analyze two-phase flow instability in parallel channels. • The influence of axial non-uniform heating on the system stability has been investigated. • Influences of various factors on system instability under cosine heat flux have been studied. • The system under top-peaked heat flux is the most stable system. - Abstract: Two-phase flow instability in parallel channels heated by axial non-uniform heat flux has been theoretically studied in this paper. The system control equations of parallel channels were established based on the homogeneous flow model in two-phase region. Semi-implicit finite-difference scheme and staggered mesh method were used to discretize the equations, and the difference equations were solved by chasing method. Cosine, bottom-peaked and top-peaked heat fluxes were used to study the influence of non-uniform heating on two-phase flow instability of the parallel channels system. The marginal stability boundaries (MSB) of parallel channels and three-dimensional instability spaces (or instability reefs) under different heat flux conditions have been obtained. Compared with axial uniform heating, axial non-uniform heating will affect the system stability. Cosine and bottom-peaked heat fluxes can destabilize the system stability in high inlet subcooling region, while the opposite effect can be found in low inlet subcooling region. However, top-peaked heat flux can enhance the system stability in the whole region. In addition, for cosine heat flux, increasing the system pressure or inlet resistance coefficient can strengthen the system stability, and increasing the heating power will destabilize the system stability. The influence of inlet subcooling number on the system stability is multi-valued under cosine heat flux

  15. Phase transformations in Ni/Ti multilayers investigated by synchrotron radiation-based x-ray diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Cavaleiro, A.J., E-mail: andre.cavaleiro@dem.uc.pt [CEMUC, Department of Mechanical Engineering, University of Coimbra, R. Luís Reis Santos, 3030-788 Coimbra (Portugal); Ramos, A.S. [CEMUC, Department of Mechanical Engineering, University of Coimbra, R. Luís Reis Santos, 3030-788 Coimbra (Portugal); Martins, R.M.S. [CENIMAT/I3N, Department of Materials Science, Faculty of Sciences and Technology, University Nova de Lisboa, 2829-516 Caparica (Portugal); Instituto de Plasmas e Fusão Nuclear, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisboa (Portugal); LATR/IST/CTN – Campus Tecnológico e Nuclear, Estrada Nacional 10 ao km 139.7, 2695-066 Bobadela LRS (Portugal); Fernandes, F.M. Braz [CENIMAT/I3N, Department of Materials Science, Faculty of Sciences and Technology, University Nova de Lisboa, 2829-516 Caparica (Portugal); Morgiel, J. [Institute of Metallurgy and Materials Science, Polish Academy of Sciences, Reymonta 25, 30-059 Cracow (Poland); Baehtz, C. [Helmholtz Zentrum Dresden Rossendorf HZDR, Institute of Ion Beam Physics and Materials Research, D-01314 Dresden (Germany); Vieira, M.T. [CEMUC, Department of Mechanical Engineering, University of Coimbra, R. Luís Reis Santos, 3030-788 Coimbra (Portugal)

    2015-10-15

    X-ray diffraction using synchrotron radiation was used for real-time investigation of the phase evolution of Ni/Ti multilayer thin films during annealing. These multilayers were deposited onto Ti–6Al–4V substrates by dc magnetron sputtering from pure Ni and Ti targets. The deposition parameters were adjusted in order to obtain a near equiatomic chemical composition and modulation periods (Λ) below 25 nm. Along the entire thickness of the films, well-defined structures with alternate Ni- and Ti-rich layers are observed, even for Λ = 4 nm. In this case, a halo characteristic of an amorphous structure is obtained, while for Λ of 12 and 25 nm the as-deposited thin films are nanocrystalline being possible to identify the (111) Ni and (002) Ti diffraction peaks. The nanolayered structure vanishes during annealing due to interdiffusion followed by reaction. The reaction between Ni and Ti to produce NiTi in the cubic B2 structure occurs in a short delay of time and within a narrow temperature range. For Λ of 25, 12 and 4 nm, the reaction temperature is close to 320, 350 and 385 °C, respectively. For higher temperatures, in addition to the austenitic phase, the NiTi{sub 2} phase is identified. The diffusion of Ti from the substrate and Ni towards the substrate could favour the precipitation of NiTi{sub 2}. - Highlights: • Alternate Ni- and Ti-rich layers are observed, even for short periods. • Phase evolution was studied using synchrotron radiation XRD during annealing. • Ni and Ti reacted at ∼300–400 °C to form B2–NiTi in a single step. • The higher the period the lower the reaction temperature. • At higher temperatures NiTi{sub 2} was detected due to Ni diffusion towards Ti{sub 6}Al{sub 4}V.

  16. Phase 1 study of the investigational Aurora A kinase inhibitor alisertib (MLN8237) in East Asian cancer patients: pharmacokinetics and recommended phase 2 dose.

    Science.gov (United States)

    Venkatakrishnan, Karthik; Kim, Tae Min; Lin, Chia-Chi; Thye, Lim Soon; Chng, Wee Joo; Ma, Brigette; Chen, Ming Huang; Zhou, Xiaofei; Liu, Hua; Kelly, Virginia; Kim, Won Seog

    2015-08-01

    This phase 1 study assessed the pharmacokinetics (PK), maximum tolerated dose (MTD)/recommended phase 2 dose (RP2D), safety, and preliminary efficacy of the investigational Aurora A kinase inhibitor, alisertib, in East Asian patients with advanced solid tumors or lymphomas. Patients received alisertib twice-daily (BID) for 7 days in 21-day cycles. Doses were escalated (3 + 3) from 30 mg BID based on cycle 1 dose-limiting toxicities (DLTs) until the MTD, followed by expansion for PK/safety characterization. Thirty-six patients (61 % Chinese, 36 % Korean, 3 % Malay) received alisertib (30 mg BID, n = 30; 40 mg BID, n = 6; median, 2.5 cycles). Alisertib exposures increased approximately dose proportionally, and mean half-life was 16 h. Geometric mean apparent oral clearance (2.65 L/h) was 40 % lower than previous estimates in Western patients, resulting in approximately 70 % higher mean dose-normalized, steady-state exposures (735 nM*h/mg) in East Asian patients. Two patients experienced DLTs at 40 mg BID (grade 3 stomatitis; grade 4 neutropenia); the MTD/RP2D was 30 mg BID. Common toxicities (grade ≥3 at RP2D) were neutropenia (50 %), diarrhea (13 %), and stomatitis (10 %). One patient with extranodal T-/NK-cell lymphoma (nasal type) achieved a partial response and 18 (51 %) had stable disease. The MTD/RP2D of alisertib in East Asian patients (30 mg BID) was lower than in Western patients (50 mg BID), consistent with higher systemic exposures in the East Asian population. Alisertib was generally well tolerated and showed signs of antitumor activity in East Asian cancer patients.

  17. Protein and Peptide Gas-phase Structure Investigation Using Collision Cross Section Measurements and Hydrogen Deuterium Exchange

    Science.gov (United States)

    Khakinejad, Mahdiar

    Protein and peptide gas-phase structure analysis provides the opportunity to study these species outside of their explicit environment where the interaction network with surrounding molecules makes the analysis difficult [1]. Although gas-phase structure analysis offers a unique opportunity to study the intrinsic behavior of these biomolecules [2-4], proteins and peptides exhibit very low vapor pressures [2]. Peptide and protein ions can be rendered in the gas-phase using electrospray ionization (ESI) [5]. There is a growing body of literature that shows proteins and peptides can maintain solution structures during the process of ESI and these structures can persist for a few hundred milliseconds [6-9]. Techniques for monitoring gas-phase protein and peptide ion structures are categorized as physical probes and chemical probes. Collision cross section (CCS) measurement, being a physical probe, is a powerful method to investigate gas-phase structure size [3, 7, 10-15]; however, CCS values alone do not establish a one to one relation with structure(i.e., the CCS value is an orientationally averaged value [15-18]. Here we propose the utility of gas-phase hydrogen deuterium exchange (HDX) as a second criterion of structure elucidation. The proposed approach incudes extensive MD simulations to sample biomolecular ion conformation space with the production of numerous, random in-silico structures. Subsequently a CCS can be calculated for these structures and theoretical CCS values are compared with experimental values to produce a pool of candidate structures. Utilizing a chemical reaction model based on the gas-phase HDX mechanism, the HDX kinetics behavior of these candidate structures are predicted and compared to experimental results to nominate the best in-silico structures which match (chemically and physically) with experimental observations. For the predictive approach to succeed, an extensive technique and method development is essential. To combine CCS

  18. Quality assurance/quality control summary report for Phase 1 of the Clinch River remedial investigation. Environmental Restoration Program

    International Nuclear Information System (INIS)

    Holladay, S.K.; Bevelhimer, M.S.; Brandt, C.C.

    1994-07-01

    The Clinch River Remedial Investigation (CRRI) is designed to address the transport, fate, and distribution of waterborne contaminants released from the US Department of Energy Oak Ridge Reservation and to assess potential risks to human health and the environment associated with these contaminants. Primary areas of investigation are Melton Hill Reservoir, the Clinch River from Melton Hill Dam to its confluence with the Tennessee River, Poplar Creek, and Watts Bar Reservoir. Phase 1 of the CRRI was a preliminary study in selected areas of the Clinch River/Watts Bar Reservoir. Fish, sediment, and water samples were collected and analyzed for inorganic, organic, and radiological parameters. Phase 1 was designed to (1) obtain high-quality data to confirm existing historical data for contaminant levels; (2) determine the range of contaminant concentrations present in the river-reservoir system; (3) identify specific contaminants of concern; and (4) establish the reference (background) concentrations for those contaminants. Quality assurance (QA) objectives for Phase I were that (1) scientific data generated would withstand scientific scrutiny; (2) data would be gathered using appropriate procedures for field sampling, chain-of-custody, laboratory analyses, and data reporting; and (3) data would be of known precision and accuracy. These objectives were met through the development and implementation of (1) a QA oversight program of audits and surveillances; (2) standard operating procedures accompanied by a training program; (3) field sampling and analytical laboratory quality control requirements; (4) data and records management systems; and (5) validation of the data by an independent reviewer. Approximately 1700 inorganic samples, 1500 organic samples, and 2200 radiological samples were analyzed and validated. The QA completeness objective for the project was to obtain valid analytical results for at least 95% of the samples collected

  19. Investigation of the separation of scandium and rare earth elements from red mud by use of reversed-phase HPLC.

    Science.gov (United States)

    Tsakanika, Lambrini V; Ochsenkühn-Petropoulou, Maria Th; Mendrinos, Leonidas N

    2004-07-01

    A chromatographic method has been developed for separation and determination of scandium (Sc) and rare earth elements (REEs) in samples from a red mud (RM)-utilization process. Reversed-phase high-performance liquid chromatography (RP-HPLC) with post-column derivatization using 4-(2-pyridylazo)-resorcinol (PAR) and UV-visible detection at 520 nm was tested using different gradient elution profiles and pH values to optimize separation and recovery, primarily for Sc but also for yttrium and the individual lanthanides, from iron present in the samples. The separation was performed in less than 20 min by use of a mobile phase gradient. The concentration of alpha-hydroxyisobutyric acid ( alpha-HIBA), as eluent, was altered from 0.06 to 0.4 mol L(-1) (pH 3.7) and 0.01 mol L(-1) sodium salt n-octane sulfonic acid (OS) was used as modifier. Very low detection limits in the nanogram range and a good resolution for Sc and REEs except for Y/Dy were achieved. Before application of the method to the red mud samples and to the corresponding bauxites, Sc and REEs were leached from red mud with 0.6 mol L(-1) HNO(3) and mostly separated, as a group, from the main elements by ion exchange/selective elution (6 mol L(-1) HNO(3)) in accordance with a pilot-plant process developed in this laboratory. After evaporation of the eluent to dryness the extracted elements were re-dissolved in the mobile phase. By use of this chromatographic method Sc, which is the most expensive of the elements investigated and occurs in economically interesting concentrations in red mud, could be separated not only from co-existing Fe but also from Y/Dy, Yb, Er, Ho, Gd, Eu, Sm, Nd, Pr, Ce and La. All the elements investigated were individually recovered. Their recoveries were found to be nearly quantitative.

  20. Insulating phase in Sr{sub 2}IrO{sub 4}: An investigation using critical analysis and magnetocaloric effect

    Energy Technology Data Exchange (ETDEWEB)

    Bhatti, Imtiaz Noor; Pramanik, A.K., E-mail: akpramanik@mail.jnu.ac.in

    2017-01-15

    The nature of insulating phase in 5d based Sr{sub 2}IrO{sub 4} is quite debated as the theoretical as well as experimental investigations have put forward evidences in favor of both magnetically driven Slater-type and interaction driven Mott-type insulator. To understand this insulating behavior, we have investigated the nature of magnetic state in Sr{sub 2}IrO{sub 4} through studying critical exponents, low temperature thermal demagnetization and magnetocaloric effect. The estimated critical exponents do not exactly match with any universality class, however, the values obey the scaling behavior. The exponent values suggest that spin interaction in present material is close to mean-field model. The analysis of low temperature thermal demagnetization data, however, shows dual presence of localized- and itinerant-type of magnetic interaction. Moreover, field dependent change in magnetic entropy indicates magnetic interaction is close to mean-field type. While this material shows an insulating behavior across the magnetic transition, yet a distinct change in slope in resistivity is observed around T{sub c}. We infer that though the insulating phase in Sr{sub 2}IrO{sub 4} is more close to be Slater-type but the simultaneous presence of both Slater- and Mott-type is the likely scenario for this material. - Highlights: • Critical analysis shows Sr{sub 2}IrO{sub 4} has ferromagnetic ordering temperature T{sub c}~225 K. • Obtained critical exponents imply spin interaction is close to mean-field model. • Analysis of magneto-entropy data also supports mean-field type interaction. • However, the presence of both itinerant and localized spin interaction is evident. • Sr{sub 2}IrO{sub 4} has simultaneous presence of both Slater- and Mott-type insulating phase.

  1. Gas-phase thermal dissociation of uranium hexafluoride: Investigation by the technique of laser-powered homogeneous pyrolysis

    International Nuclear Information System (INIS)

    Bostick, W.D.; McCulla, W.H.; Trowbridge, L.D.

    1987-04-01

    In the gas-phase, uranium hexafluoride decomposes thermally in a quasi-unimolecular reaction to yield uranium pentafluoride and atomic fluorine. We have investigated this reaction using the relatively new technique of laser-powered homogeneous pyrolysis, in which a megawatt infrared laser is used to generate short pulses of high gas temperatures under strictly homogeneous conditions. In our investigation, SiF 4 is used as the sensitizer to absorb energy from a pulsed CO 2 laser and to transfer this energy by collisions with the reactant gas. Ethyl chloride is used as an external standard ''thermometer'' gas to permit estimation of the unimolecular reaction rate constants by a relative rate approach. When UF 6 is the reactant, CF 3 Cl is used as reagent to trap atomic fluorine reaction product, forming CF 4 as a stable indicator which is easily detected by infrared spectroscopy. Using these techniques, we estimate the UF 6 unimolecular reaction rate constant near the high-pressure limit. In the Appendix, we describe a computer program, written for the IBM PC, which predicts unimolecular rate constants based on the Rice-Ramsperger-Kassel theory. Parameterization of the theoretical model is discussed, and recommendations are made for ''appropriate'' input parameters for use in predicting the gas-phase unimolecular reaction rate for UF 6 as a function of temperature and gas composition and total pressure. 85 refs., 17 figs., 14 tabs

  2. Phase I Investigations at the Former CCC/USDA Grain Storage Facility in Montgomery City, Missouri, in 2010-2011

    Energy Technology Data Exchange (ETDEWEB)

    LaFreniere, Lorraine M. [Argonne National Lab. (ANL), Argonne, IL (United States). Environmental Science Division. Applied Geoscience and Environmental Restoration Program

    2012-11-01

    This report presents the technical findings of Phase I of Argonne’s studies. The Phase I field investigation was initiated on October 18, 2010. The work was conducted in accord with (1) the final site-specific Phase I Work Plan for Montgomery City (Argonne 2010; approved by the MDNR [2010]); (2) applicable Missouri regulations; and (3) the standard operating procedures, quality assurance/quality control (QA/QC) measures, and general health and safety policies outlined in the Master Work Plan (Argonne 2002) for operations in Kansas, which was reviewed by the MDNR and accepted for current use. A draft master plan specific to work in Missouri and a set of draft standard operating procedures are in review with the MDNR. The site-specific Work Plan for Montgomery City (Argonne 2010) (1) summarizes the pre-existing knowledge base for the Montgomery City investigation site compiled by Argonne and (2) describes the site-specific technical objectives and the intended scope of work developed for the first phase of the investigation. Three primary technical objectives were identified for the Phase I studies, as follows: 1. Update the presently identified inventory and status of private and public drinking water wells in the immediate vicinity of the former CCC/USDA grain storage facility, and sample the identified wells for volatile organic compounds (VOCs) and geochemical analyses. In conjunction with this effort, determine the present sources(s) of drinking water for all residents in an approximate 0.5-mi radius of the former CCC/USDA facility. 2. Investigate for possible evidence of a soil source of carbon tetrachloride contamination in the unconsolidated sediments beneath the former CCC/USDA facility that might affect the underlying bedrock aquifer units. 3. Obtain preliminary information on the site-specific lithologic and hydrologic characteristics of the unconsolidated sediments overlying bedrock at the former CCC/USDA grain storage location. Section 2 of this report

  3. A fluid biopsy as investigating technology for the fluid phase of solid tumors

    Science.gov (United States)

    Kuhn, Peter; Bethel, Kelly

    2012-02-01

    Reliable measurement of internal bodily substances and structures is one of the cornerstones of modern medicine. Progress in cancer medicine, like that in many medical fields, must encompass and take advantage of progress in the physical sciences. Historically, the development and refinement of physical sciences-based detection of biological entities precedes periods of great advancements in therapies. To treat broken limbs and arthritis, we are indebted to Conrad Roentgen's discovery of x-rays by which we can evaluate the bones; to apply gamma knife therapy for cancer, we are indebted to Marie Curie's discoveries about radioactivity by which we can eradicate tumors; to manage the complications of diabetes, we are indebted to Tom Clemens, Ames Pharmaceuticals and Dick Bernstein's refinement of direct blood glucose measurement technology by which we can count, hour-to-hour, the waxing and waning of blood sugar levels; to understand anything at all on the cellular level, we are indebted to Antonie van Leeuwenhoek's microscope, by which we can see our cells. The application of physical sciences perspectives to biological and medical problems has a long and productive history. As of late, however, the increasing compartmentalization of science and exponential increases of knowledge in both arenas has resulted in a rift between the two. The NCI has initiated a research network establishing multiple centers of investigation, the Physical Sciences in Oncology Centers (http://physics.cancer.gov), which seek to mend the rift. Each headed by a pair of investigators, one in the physical sciences and one in the biological sciences, the centers seek to bring the advances and breakthroughs of the physical sciences world to bear on the question of cancer. This issue of physical biology contains a series of articles exploring the utility and applicability of a new method for measuring cancer as it spreads, developed at the Scripps Physical Oncology Center. Although some progress

  4. An overview of the MIZ-1 borehole investigations during phase I/II. MIZ-1 progress report 03-01

    International Nuclear Information System (INIS)

    Ota, Kunio; Takeuchi, Shinji; Ikeda, Koki

    2004-05-01

    Surface-based investigations have now been carried out, in a step-by-step fashion, with the main aims of the development of conceptual models of the geological environment and the enhancement of the understanding of the undisturbed deep geological environment before excavation of the shafts and experimental drifts. The MIZ-1 borehole investigation programme was launched in December 2002, as a step of the field investigations at the MIU Construction Site. The overall goals of the MIZ-1 borehole investigations are to characterise the geological environment from the surface to over 1,000 m depth in the crystalline basement, to establish baseline conditions before excavation of the shafts and experimental drifts, and to provide a deep borehole for observing hydraulic responses during the shaft and drift excavation and experiments in the drifts during the Construction and the Operation Phases. The borehole is planned to be drilled in an overall south-westerly direction from the north-eastern area of the MIU Site. The planned inclination varies from vertical at shallower depths to 12deg from vertical at greater depths down to 1,350 m along the borehole length, which will be achieved by controlled directional drilling. In MIZ-1 Phase I/II (from March to May 2003), the borehole was drilled vertically, through the entire sedimentary formations, down to 123.00 m in the uppermost part of the Toki granite at the MIU Construction Site. The new method of wireline core drilling with a downhole motor was introduced for the drilling. Planned geological, geophysical and hydrochemical investigations and complementary hydraulic and hydrochemical monitoring were performed. In addition, as a complete loss of drilling fluid was encountered at 115.85 m along the borehole length, modified work procedures resulted in the execution of hydraulic tests with groundwater sampling, from necessity, in that section and of further drilling work. The local QC system was applied to all the

  5. Non-steady experimental investigation on an integrated thermal management system for power battery with phase change materials

    International Nuclear Information System (INIS)

    Shi, Shang; Xie, Yongqi; Li, Ming; Yuan, Yanping; Yu, Jianzu; Wu, Hongwei; Liu, Bin; Liu, Nan

    2017-01-01

    Highlights: • An integrated thermal management system for power battery is designed. • The battery temperature rise is a non-steady process for charge and discharge. • A mathematical model can accurately represent temperature rise characteristics. • The heat generation power of the battery is calculated theoretically. • The excess temperatures and thermal resistances affect the system performance. - Abstract: A large amount of heat inside the power battery must be dissipated to maintain the temperature in a safe range for the hybrid power train during high-current charging/discharging processes. In this article, a combined experimental and theoretical study has been conducted to investigate a newly designed thermal management system integrating phase change material with air cooling. An unsteady mathematical model was developed for the battery with the integrated thermal management system. Meanwhile, the heat generation power, thermal resistance, and time constant were calculated. The effect of several control parameters, such as thermal resistance, initial temperature, melting temperature and ambient temperature, on the performance of the integrated thermal management system were analyzed. The results indicated that: (1) the calculated temperature rise of the battery was in good agreement with the experimental data. The appropriate operation temperature of the battery was attained by the action of the phase change storage energy unit which is composed of copper foam and n-Eicosane, (2) the remarkable decrease of the battery temperature can be achieved by reducing the convection thermal resistance or increasing the conductivity of the phase change storage energy unit, where the latter could be the better option due to no additional energy consumption. When convective resistance and thermal resistance between the battery surface and the phase change storage energy unit are less than 2.03 K/W and 1.85 K/W, respectively, the battery will not exceed the

  6. Investigation for three-dimensional DNAPL migration and dissolved phase concentration changes in porous media by water table fluctuation

    Science.gov (United States)

    Lee, D.; Moon, H.; Lee, K.

    2011-12-01

    A number of two-dimensional DNAPL migration studies in groundwater have been performed by other researchers. To date, however, three-dimensional study has not been done and study considering water table fluctuation are currently lacking as well. In this study, well controlled three-dimensional laboratory experiment was performed to investigate migration of TCE, NAPL saturation and morphological DNAPL pool in the groundwater. The 20ml TCE (Trichloroethylene) and Oil Red O was used to visualize TCE that was used in this study. The column (43cm diameter and 40cm height) is big enough so free-phase TCE cannot reach column wall or bottom. Previous study at Wonju-si, Gangwon-do, South Korea shows TCE concentration changes proportional to rainfall intensity (Seasonal variation). The main objective of this study is to clarify variation of NAPL migration and dissolved NAPL concentration by water table changes. Water samples were collected at three-dimensional points (at each 3cm vertical depth and 7cm lateral depth) and gas phase TCE and effluent samples were also analyzed. At the end of the experiment, sand layers were removed one by one and pictures of cross-sectional area at various depths were taken. The dyed areas where free-phase TCE exist were analyzed by modal counting. The result shows that the free-phase TCE infiltrates through the unsaturated zone and accumulated around water table spreading laterally, some of TCE migrate through the saturated zone until all free-phase TCE is adsorbed on the sand grains or dissolved into water. And after water table rising, some point shows reduced concentration by dilution with fresh water but the highest concentration of TCE is higher than the concentration that is sampled before the water table rising. (Highest TCE concentration before water table rising: 443.28 ppm, after water table rising: 779.1 ppm) This means, remediation action should be taken with considering seasonal rainfall variation. NAPL saturation and the depth

  7. Pumpless geothermal heat probe - Phase 1: investigation of potential and energetic and commercial feasibility; Pumpenlose Erdwaermesonde Phase 1: Potentialabklaerung, Machbarkeitsstudie energetisch und wirtschaftlich

    Energy Technology Data Exchange (ETDEWEB)

    Peterlunger, A.; Ehrbar, M. [Interstaatliche Hochschule fuer Technik Buchs, Labor fuer Thermodynamik und Kaeltetechnik, Buchs (Switzerland); Bassetti, S.; Rohner, E. [Geowatt AG, Zuerich (Switzerland)

    2004-07-01

    This final report for the Swiss Federal Office of Energy (SFOE) discusses the results of an investigation made at the University of Applied Science in Buchs, Switzerland, on the subject of thermosyphon-based geothermal heat probes. These probes are considered as being a further development of traditional, brine-filled vertical geothermal probes and possess the advantage of not needing a pump to circulate the heat-transfer medium. The resulting improvement in the Coefficient of Performance (COP) of such heat-pump systems is quoted as being 12 to 15%. The question of appropriate probe design - probe-diameters of 40 mm and lengths of 350 m are considered to be optimal - is discussed and compared with actual installations that have already been made in Switzerland. As far as heat transfer media are concerned, the advantages and disadvantages of ammonium and carbon dioxide are discussed. Also, the need for inexpensive ways of repairing possible leaks in these high-pressure systems is discussed. The report also looks at the possibilities of using such probes for cooling applications. The physics of the heat-transfer process is explained and the results of numerical modelling of the ground-loops are presented. Comparisons are made between the energy-efficiency and costs of such systems and conventional heat-pump systems using vertical and horizontal heat exchangers as well as those using ground-water as a source of heat. The report is concluded with a forward look at the second phase of the project.

  8. An investigation of the interfacial characteristics of two-phase stratified flow in a nearly horizontal channel

    International Nuclear Information System (INIS)

    Yu, Seon Oh

    2000-02-01

    A theoretical flow transition criterion to slug flow or onset of countercurrent flow limitation (CCFL) in a nearly horizontal stratified flow, considering the effect of steam condensation, has been derived. In addition, the interfacial characteristics of a two-phase stratified flow in a nearly horizontal channel have been investigated experimentally for two important interfacial phenomena, i.e., heat and momentum transfers, which are given as the essential interfacial boundary conditions to analyze the two-phase flow. To obtain the experimental data for onset of CCFL and to understand the interfacial phenomena, a series of experiments have also been performed in a countercurrent stratified flow test facility with 0.083 m inner diameter and 2.2 m length of test section. For the flow instability criterion, i.e., a transition condition from stratified flow to slug flow or onset of CCFL, a theoretical model that includes the steam condensation effect has been developed using the concept of total energy balance over the interfacial wave crest. The present model is more general in that it becomes the same form of the previous models if the effects of interfacial shear stress and steam condensation were neglected in a rectangular channel. the comparisons between the theoretical criterion for CCFL and the experimental data show that the present model can predict well the present experimental data of a circular tube as well as those of rectangular ducts from the previous study. Results of a parametric study of the steam condensation effect using the present model show that, when all local conditions are similar, the model-predicted critical gas velocities with the steam condensation factor are lower than those without the steam condensation factor, which indicates that the steam condensation phenomenon has a destabilizing effect on CCFL. In addition, using the present theoretical criterion, it is possible to explain the effect of steam condensation on the CCFL

  9. X-Ray Microspectroscopic Investigations of Remote Aerosol Composition and Changes in Aerosol Microstructure and Phase State upon Hydration

    Science.gov (United States)

    Andreae, M. O.; Artaxo, P.; Bechtel, M.; Förster, J. D.; Kilcoyne, A. L. D.; Krüger, M. L.; Pöhlker, C.; Saturno, J.; Weigand, M.; Wiedemann, K. T.

    2014-12-01

    Atmospheric aerosols play a crucial role in the Earth's climate system and hydrological cycle by scattering and absorbing sunlight and affecting the formation and development of clouds and precipitation. Our research focuses on aerosols in remote regions, in order to characterize the properties and sources of natural aerosol particles and the extent of human perturbations of the aerosol burden. The phase and mixing state of atmospheric aerosols, and particularly their hygroscopic response to relative humidity (RH) variations, is a central determinant of their atmospheric life cycle and impacts. We present an investigation using X-ray microspectroscopy on submicrometer aerosols under variable RH conditions, showing in situ changes in morphology, microstructure, and phase state upon humidity cycling. We applied Scanning Transmission X-ray Microscopy with Near-Edge X-ray Absorption Fine Structure spectroscopy (STXM-NEXAFS) under variable RH conditions to standard aerosols for a validation of the experimental approach and to internally mixed aerosol particles from the Amazonian rain forest collected during periods with anthropogenic pollution. The measurements were conducted at X-ray microscopes at the synchrotron facilities Advanced Light Source (ALS) in Berkeley, USA, and BESSY II in Berlin, Germany. Upon hydration, we observed substantial and reproducible changes in microstructure of the Amazonian particles (internal mixture of secondary organic material, ammoniated sulfate, and soot), which appear as mainly driven by efflorescence and recrystallization of sulfate salts. Multiple solid and liquid phases were found to coexist, especially in intermediate humidity regimes (60-80% RH). This shows that X-ray microspectroscopy under variable RH is a valuable technique to analyze the hygroscopic response of individual ambient aerosol particles. Our initial results underline that RH changes can trigger strong particle restructuring, in agreement with previous studies on

  10. Simulation investigation of thermal phase transformation and residual stress in single pulse EDM of Ti-6Al-4V

    Science.gov (United States)

    Tang, Jiajing; Yang, Xiaodong

    2018-04-01

    The thermal phase transformation and residual stress are ineluctable in the electrical discharge machining (EDM) process, and they will greatly affect the working performances of the machined surface. This paper presents a simulation study on the thermal phase transformation and residual stress in single-pulse EDM of Ti-6Al-4V, which is the most popular titanium alloy in fields such as aircraft engine and some other leading industries. A multi-physics model including thermal, hydraulic, metallography and structural mechanics was developed. Based on the proposed model, the thickness and metallographic structure of the recast layer and heat affected layer (HAZ) were investigated. The distribution and characteristics of residual stress around the discharge crater were obtained. The recast layer and HAZ at the center of crater are found to be the thinnest, and their thicknesses gradually increase approaching the periphery of the crater. The recast layer undergoes a complete α‧ (martensitic) transformation, while the HAZ is mainly composed by the α  +  β  +  α‧ three-phase microstructure. Along the depth direction of crater, the Von Mises stress increases first and then decreases, reaching its maximal value near the interface of recast layer and HAZ. In the recast layer, both compressive stress component and tensile stress component are observed. ANOVA results showed that the influence of discharge current on maximal tensile stress is more significant than that of pulse duration, while the pulse duration has more significant influence on average thickness of the recast layer and the depth location of the maximal tensile stress. The works conducted in this study will help to evaluate the quality and integrity of EDMed surface, especially when the non-destructive testing is difficult to achieve.

  11. Investigation of a Five-Phase Dual-Rotor Permanent Magnet Synchronous Motor Used for Electric Vehicles

    Directory of Open Access Journals (Sweden)

    Yumeng Li

    2014-06-01

    Full Text Available This paper presents a novel five-phase permanent magnet synchronous motor (PMSM, which contains dual rotors and a single stator, equivalent to two five-phase motors working together. Thus, this kind of motor has the potential of good fault tolerant capability and high torque density, which makes it appropriate for use in electric vehicles. In view of the different connection types, the inside and outside stator windings can be driven in series or parallel, which results in the different performances of the magnetomotive force (MMF and torque under open-circuit fault conditions. By decomposing the MMF, the reason that torque ripple increases after open-circuit faults is explained, and the relationship between MMF and torque is revealed. Then, the current control strategy is applied to adjust the open-circuit faults, and the electromagnetic analysis and MMF harmonics analysis are performed to interpret the phenomenon that the torque ripple is still larger than in the normal situation. The investigations are verified by finite element analysis results.

  12. Investigation of heat transfer and pressure drop of CO(2) two-phase flow in a horizontal minichannel

    CERN Document Server

    Wu, J; Haug, F; Franke, C; Bremer, J; Eisel, T; Koettig, T

    2011-01-01

    An innovative cooling system based on evaporative CO(2) two-phase flow is under investigation for the tracker detectors upgrade at CERN (European Organization for Nuclear Research). The radiation hardness and the excellent thermodynamic properties emphasize carbon dioxide as a cooling agent in the foreseen minichannels. A circular stainless steel tube in horizontal orientation with an inner diameter of 1.42 mm and a length of 0.3 m has been used as a test section to perform the step-wise scanning of the vapor quality in the entire two-phase region. To characterize the heat transfer and the pressure drop depending on the vapor quality in the tube, measurements have been performed by varying the mass flux from 300 to 600 kg/m(2) s, the heat flux from 7.5 to 29.8 kW/m(2) and the saturation temperature from -40 to 0 degrees C (reduced pressures from 0.136 to 0.472). Heat transfer coefficients between 4 kW/m(2) K and 28 kW/m(2) K and pressure gradients up to 75 kPa/m were registered. The measured data was analyzed...

  13. Experimental Investigation of Two-Phase Oil (D130)-Water Flow in 4″ Pipe for Different Inclination Angles

    Science.gov (United States)

    Shaahid, S. M.; Basha, Mehaboob; Al-Hems, Luai M.

    2018-03-01

    Oil and water are often produced and transported together in pipelines that have various degrees of inclination from the horizontal. The flow of two immiscible liquids oil and water in pipes has been a research topic since several decades. In oil and chemical industries, knowledge of the frictional pressure loss in oil-water flows in pipes is necessary to specify the size of the pump required to pump the emulsions. An experimental investigation has been carried out for measurement of pressure drop of oil (D130)-water two-phase flows in 4 inch diameter inclined stainless steel pipe at different flow conditions. Experiments were conducted for different inclination angles including; 0°, 15°, 30° (for water cuts “WC” 0 - 100%). The flow rates at the inlet were varied from 4000 to 8000 barrels-per-day (BPD). For a given flow rate the frictional pressure drop has been found to increase (for all angles) from WC = 0 - 60%, and thereafter friction pressure drop decreases, this could be due phase inversion. For a given WC 40%, the frictional pressure drop has been found to increase with angle and flow rate. It has been noticed that inclination angle has appreciable effect on frictional pressure drop.

  14. First-Principles Investigation of Phase Stability, Electronic Structure and Optical Properties of MgZnO Monolayer

    Directory of Open Access Journals (Sweden)

    Changlong Tan

    2016-10-01

    Full Text Available MgZnO bulk has attracted much attention as candidates for application in optoelectronic devices in the blue and ultraviolet region. However, there has been no reported study regarding two-dimensional MgZnO monolayer in spite of its unique properties due to quantum confinement effect. Here, using density functional theory calculations, we investigated the phase stability, electronic structure and optical properties of MgxZn1−xO monolayer with Mg concentration x range from 0 to 1. Our calculations show that MgZnO monolayer remains the graphene-like structure with various Mg concentrations. The phase segregation occurring in bulk systems has not been observed in the monolayer due to size effect, which is advantageous for application. Moreover, MgZnO monolayer exhibits interesting tuning of electronic structure and optical properties with Mg concentration. The band gap increases with increasing Mg concentration. More interestingly, a direct to indirect band gap transition is observed for MgZnO monolayer when Mg concentration is higher than 75 at %. We also predict that Mg doping leads to a blue shift of the optical absorption peaks. Our results may provide guidance for designing the growth process and potential application of MgZnO monolayer.

  15. Tensiometric investigation of the interaction and phase separation in a polymer mixture–ionic surfactant ternary system

    Directory of Open Access Journals (Sweden)

    JAROSLAV M. KATONA

    2010-06-01

    Full Text Available The interaction and phase separation in a ternary mixture composed of hydroxypropyl methyl cellulose (HPMC, sodium carboxymethyl cellulose (NaCMC, and sodium dodecylsulfate (SDS were investigated by tensiometry. Surface tension measurements of binary mixtures (0.7 % HPMC and 0.00–2.00 % SDS and of ternary mixtures (0.7 % HPMC, 0.3 % NaCMC, and 0.00–2.00 % SDS were performed. The measurements indicated interaction between HPMC and SDS, which resulted in HPMC–SDS complex formation. The critical association concentration, CAC, and polymer saturation point, PSP, were determined. Phase separation of ternary HPMC/SDS/NaCMC mixtures occurs at SDS concentration > CAC, i.e., when the HPMC–SDS complex is formed. The volume of the coacervate increases with increasing SDS concentration, and at SDS concentrations > 1.00 %, the coacervate vanishes. The surface tensions (s of ternary HPMC/SDS/NaCMC mixtures in the pre-coacervation region and at the onset of the coacervation region are similar to the σ of the corresponding binary HPMC–SDS mixtures, while in the coacervation and post coacervation region, they are close to the s of the corresponding SDS solutions

  16. Investigational drugs in Phase II clinical trials for the treatment of obesity: implications for future development of novel therapies.

    Science.gov (United States)

    Jackson, V Margaret; Price, David A; Carpino, Philip A

    2014-08-01

    The discovery of new antiobesity agents has attracted considerable interest over the past decade, but many of the investigational agents that have advanced into human clinical trials have shown unacceptable adverse events and/or efficacy profiles. This review summarizes the available preclinical and clinical data of antiobesity drugs currently in Phase II clinical trials. It also provides a brief summary of the mechanisms underlying the regulation of energy homeostasis. New approaches to solving the obesity epidemic are needed, exemplified in part by some of the agents currently in Phase II clinical trials. Weight loss treatments could be tailored to specific subpopulations such as morbidly obese individuals with a high risk for complications or obese patients with a specific genotype. Fixed dose combinations of drugs that target multiple complementary pathways could be developed to deliver durable, 10% or greater weight loss. A shift away from pharmacological agents that act on pathways in the CNS could lead to drugs with fewer side effects and more favorable risk/benefit ratios.

  17. Theoretical investigation of the long-lived metastable AlO{sup 2+} dication in gas phase

    Energy Technology Data Exchange (ETDEWEB)

    Sghaier, Onsi [Université Paris-Est, Laboratoire Modélisation et Simulation Multi Echelle, MSME UMR 8208 CNRS, 5 bd Descartes, 77454 Marne-la-Vallée (France); Abdallah, Hassan H. [Computational Nanotechnology Research Lab. CNRL, Salahaddin University, 44001 Erbil (Iraq); Department of Chemistry, College of Education, Salahaddin University, 44001 Erbil (Iraq); Abdullah, Hewa Y. [Computational Nanotechnology Research Lab. CNRL, Salahaddin University, 44001 Erbil (Iraq); Department of Physics, College of Education, Salahaddin University, 44001 Erbil (Iraq); Jaidane, Nejm Eddine [Laboratoire de Spectroscopie Atomique, Moléculaire et Applications – LSAMA, Université de Tunis, Tunis (Tunisia); Al Mogren, Muneerah Mogren [Chemistry Department, Faculty of Science, King Saud University, PO Box 2455, Riyadh 11451 (Saudi Arabia); Hochlaf, Majdi, E-mail: hochlaf@univ-mlv.fr [Université Paris-Est, Laboratoire Modélisation et Simulation Multi Echelle, MSME UMR 8208 CNRS, 5 bd Descartes, 77454 Marne-la-Vallée (France)

    2016-09-30

    Highlights: • Theoretical investigation of gas-phase molecular species AlO{sup 2+}. • Spectroscopic parameters of this dication in its electronic ground and exited states. • Theoretical double ionization spectrum of AlO. - Abstract: We report the results of a detailed theoretical study of the electronic ground and excited states of the gas-phase doubly charged ion AlO{sup 2+} using high-level ab initio computer calculations. Both standard and explicitly correlated methods were used to calculate their potential energy curves and spectroscopic parameters. These computations show that the ground state of AlO{sup 2+} is X{sup 2}Π. The internuclear equilibrium distance of AlO{sup 2+}(X{sup 2}Π) is computed 1.725 Å. We also deduced the adiabatic double ionization and charge stripping energies of AlO to be about 27.45 eV and 17.80 eV, respectively.

  18. Experimental and numerical investigation of shock wave propagation through complex geometry, gas continuous, two-phase media

    Energy Technology Data Exchange (ETDEWEB)

    Chien-Chih Liu, James [Univ. of California, Berkeley, CA (United States)

    1993-01-01

    The work presented here investigates the phenomenon of shock wave propagation in gas continuous, two-phase media. The motivation for this work stems from the need to understand blast venting consequences in the HYLIFE inertial confinement fusion (ICF) reactor. The HYLIFE concept utilizes lasers or heavy ion beams to rapidly heat and compress D-T targets injected into the center of a reactor chamber. A segmented blanket of falling molten lithium or Li2BeF4 (Flibe) jets encircles the reactor`s central cavity, shielding the reactor structure from radiation damage, absorbing the fusion energy, and breeding more tritium fuel. X-rays from the fusion microexplosion will ablate a thin layer of blanket material from the surfaces which face toward the fusion site. This generates a highly energetic vapor, which mostly coalesces in the central cavity. The blast expansion from the central cavity generates a shock which propagates through the segmented blanket - a complex geometry, gas-continuous two-phase medium. The impulse that the blast gives to the liquid as it vents past, the gas shock on the chamber wall, and ultimately the liquid impact on the wall are all important quantities to the HYLIFE structural designers.

  19. Final report : phase I investigation at the former CCC/USDA grain storage facility in Savannah, Missouri.

    Energy Technology Data Exchange (ETDEWEB)

    LaFreniere, L. M.; Environmental Science Division

    2010-08-05

    Agency of the USDA and the MoDNR, to address carbon tetrachloride contamination potentially associated with a number of former CCC/USDA grain storage facilities in Missouri. The site characterization at Savannah is being conducted on behalf of the CCC/USDA by the Environmental Science Division of Argonne National Laboratory. A phased approach is being employed by the CCC/USDA and Argonne, with the approval of the MoDNR, so that information obtained and interpretations developed during each incremental stage of the study can be used most effectively to guide subsequent aspects of the program. This report presents the technical findings of Phase I of Argonne's studies. The Phase I investigation was undertaken in accord with the final site-specific Phase I Work Plan for Savannah (Argonne 2007), as well as with the Master Work Plan (MWPK) for CCC/USDAArgonne operations in the state of Kansas (Argonne 2002), which the MoDNR reviewed and approved (with minor revisions) for temporary use in Missouri to facilitate the start-up of the CCC/USDA's activities at Savannah. (Argonne is developing a similar Master Work Plan for operations in Missouri that is based on the existing MWPK, with the approval of the MoDNR. The Missouri document has not been finalized, however, at this time.) The site-specific Savannah Work Plan (Argonne 2007; approved by the MoDNR [2007a]) (1) summarized the pre-existing knowledge base for the Savannah investigation site compiled by Argonne and (2) described the site-specific technical objectives and the intended scope of work developed for this phase of the investigation. Four primary technical objectives were identified for the Phase I studies, as follows: (1) Update the previous (MoDNR 2000a,b) inventory and status of private wells in the immediate vicinity of the former CCC/USDA grain storage facility, and sample the identified wells for analyses for volatile organic compounds (VOCs) and geochemical constituents. (2) Investigate for possible

  20. The piston-cylinder apparatus for in-situ structural investigations of high-pressure phases of gas hydrates with the use of synchrotron radiation

    CERN Document Server

    Mirinski, D S; Larionova, E G; Kurnosov, A V; Ancharov, A I; Dyadin, Y A; Tolochko, B P; Sheromov, M A

    2001-01-01

    The piston-cylinder apparatus for the investigation of high-pressure gas hydrate phases by the powder diffraction method is presented. The first results concerning the nature of the high-pressure gas hydrate phase in the sulfur hexafluoride-water system are reported.

  1. Investigation on disordering (PAC-method) and diffusion in the ordered β-Hume-Rothery-Phase PdIn

    International Nuclear Information System (INIS)

    Hahn, H.

    1982-01-01

    The author presents PAC measurements on the ordered intermetallic B2-phase PdIn with the isotope In 111 in order to investigate the structural and thermal disorder. The experimental data obtained confirm the disorder model being valid for NiAl, CoGa, CoAl and NiAl. Additional experiments on self-diffusion of Pd 109 and In 114 in the temperature range 1000K-1500K in the alloy PdIn under various compositions yield the frequency-factors and the related activation energies. A detailed discussion of the possible diffusion mechanisms leads to a model which includes direct jumps to second neighbour places and excludes tripeldefect motion and the ring-jump mechanism. (RK)

  2. External and internal structure of weevils (Insecta: Coleoptera) investigated with phase-contrast X-ray imaging

    International Nuclear Information System (INIS)

    Hoennicke, M.G.; Cusatis, C.; Rigon, L.; Menk, R.-H.; Arfelli, F.; Foerster, L.A.; Rosado-Neto, G.H.

    2010-01-01

    Weevils (Coleoptera: Curculionidae) are identified by the external structure (dorsal, ventral and lateral features) and also by internal structure. The genitalia can be used to distinguish the sex and to identify the insects when the external structure appears identical. For this purpose, a destructive dissecting microscopy procedure is usually employed. In this paper, phase contrast X-ray imaging (radiography and tomography) is employed to investigate the internal structure (genitalia) of two entire species of weevils that presents very similar external structures (Sitophilus oryzae and Sitophilus zeamais). The detection of features, which looks like the genital structure, shows that such non-destructive technique could be used as an alternative method for identification of insects. This method is especially useful in examining the internal features of precious species from museum collections, as already described in the recent literature.

  3. External and internal structure of weevils (Insecta: Coleoptera) investigated with phase-contrast X-ray imaging

    Science.gov (United States)

    Hönnicke, M. G.; Cusatis, C.; Rigon, L.; Menk, R.-H.; Arfelli, F.; Foerster, L. A.; Rosado-Neto, G. H.

    2010-08-01

    Weevils (Coleoptera: Curculionidae) are identified by the external structure (dorsal, ventral and lateral features) and also by internal structure. The genitalia can be used to distinguish the sex and to identify the insects when the external structure appears identical. For this purpose, a destructive dissecting microscopy procedure is usually employed. In this paper, phase contrast X-ray imaging (radiography and tomography) is employed to investigate the internal structure (genitalia) of two entire species of weevils that presents very similar external structures ( Sitophilus oryzae and Sitophilus zeamais). The detection of features, which looks like the genital structure, shows that such non-destructive technique could be used as an alternative method for identification of insects. This method is especially useful in examining the internal features of precious species from museum collections, as already described in the recent literature.

  4. External and internal structure of weevils (Insecta: Coleoptera) investigated with phase-contrast X-ray imaging

    Energy Technology Data Exchange (ETDEWEB)

    Hoennicke, M.G., E-mail: mhonnicke@bnl.go [NSLS II, Brookhaven National Laboratory, Upton, NY (United States); Cusatis, C. [LORXI, Departamento de Fisica-UFPR, Curitiba (Brazil); Rigon, L. [Instituto Nazionale di Fisica Nucleare, Trieste (Italy); Menk, R.-H. [Sincrotrone Trieste SCPa, Basovizza, Trieste (Italy); Arfelli, F. [Instituto Nazionale di Fisica Nucleare, Trieste (Italy); Dipartamento di Fisica-Universita di Trieste, Trieste (Italy); Foerster, L.A.; Rosado-Neto, G.H. [Departamento de Zoologia-UFPR, Curitiba (Brazil)

    2010-08-21

    Weevils (Coleoptera: Curculionidae) are identified by the external structure (dorsal, ventral and lateral features) and also by internal structure. The genitalia can be used to distinguish the sex and to identify the insects when the external structure appears identical. For this purpose, a destructive dissecting microscopy procedure is usually employed. In this paper, phase contrast X-ray imaging (radiography and tomography) is employed to investigate the internal structure (genitalia) of two entire species of weevils that presents very similar external structures (Sitophilus oryzae and Sitophilus zeamais). The detection of features, which looks like the genital structure, shows that such non-destructive technique could be used as an alternative method for identification of insects. This method is especially useful in examining the internal features of precious species from museum collections, as already described in the recent literature.

  5. An investigation on the effects of phase change material on material components used for high temperature thermal energy storage system

    Science.gov (United States)

    Kim, Taeil; Singh, Dileep; Zhao, Weihuan; Yua, Wenhua; France, David M.

    2016-05-01

    The latent heat thermal energy storage (LHTES) systems for concentrated solar power (CSP) plants with advanced power cycle require high temperature phase change materials (PCMs), Graphite foams with high thermal conductivity to enhance the poor thermal conductivity of PCMs. Brazing of the graphite foams to the structural metals of the LHTES system could be a method to assemble the system and a method to protect the structural metals from the molten salts. In the present study, the LHTES prototype capsules using MgCl2-graphite foam composites were assembled by brazing and welding, and tested to investigate the corrosion attack of the PCM salt on the BNi-4 braze. The microstructural analysis showed that the BNi-4 braze alloy can be used not only for the joining of structure alloy to graphite foams but also for the protecting of structure alloy from the corrosion by PCM.

  6. Phase I remedial investigation report of Waste Area Grouping 2 at Oak Ridge National Laboratory, Oak Ridge, Tennessee

    Energy Technology Data Exchange (ETDEWEB)

    Miller, D.E. [ed.

    1995-07-01

    This report presents the activities and findings of the first phase of a three-phase remedial investigation (RI) of Waste Area Grouping (WAG) 2 at Oak Ridge National Laboratory (ORNL) in Oak Ridge, Tennessee, and updates the scope and strategy for WAG-2-related efforts. WAG 2 contains White Oak Creek (WOC) and its tributaries downstream of the ORNL main plant area, White Oak Lake, White Oak Creek Embayment on the Clinch River, and the associated floodplain and subsurface environment. Water, sediment, soil, and biota in WAG 2 are contaminated and continue to receive contaminants from upgradient WAGs. This report includes field activities completed through October 1992. The remediation of WAG 2 is scheduled to follow the cessation of contaminant input from hydrologically upgradient WAGs. While upgradient areas are being remediated, the strategy for WAG 2 is to conduct a long-term monitoring and investigation program that takes full advantage of WAG 2`s role as an integrator of contaminant fluxes from other ORNL WAGs and focuses on four key goals: (1) Implement, in concert with other programs, long-term, multimedia environmental monitoring and tracking of contaminants leaving other WAGs, entering WAG 2, and being transported off-site. (2) Provide a conceptual framework to integrate and develop information at the watershed-level for pathways and processes that are key to contaminant movement, and so support remedial efforts at ORNL. (3) Provide periodic updates of estimates of potential risk (both human health and ecological) associated with contaminants accumulating in and moving through WAG 2 to off-site areas. (4) Support the ORNL Environmental Restoration Program efforts to prioritize, remediate, and verify remedial effectiveness for contaminated sites at ORNL, through long-term monitoring and continually updated risk assessments.

  7. Phase I remedial investigation report of Waste Area Grouping 2 at Oak Ridge National Laboratory, Oak Ridge, Tennessee

    International Nuclear Information System (INIS)

    Miller, D.E.

    1995-07-01

    This report presents the activities and findings of the first phase of a three-phase remedial investigation (RI) of Waste Area Grouping (WAG) 2 at Oak Ridge National Laboratory (ORNL) in Oak Ridge, Tennessee, and updates the scope and strategy for WAG-2-related efforts. WAG 2 contains White Oak Creek (WOC) and its tributaries downstream of the ORNL main plant area, White Oak Lake, White Oak Creek Embayment on the Clinch River, and the associated floodplain and subsurface environment. Water, sediment, soil, and biota in WAG 2 are contaminated and continue to receive contaminants from upgradient WAGs. This report includes field activities completed through October 1992. The remediation of WAG 2 is scheduled to follow the cessation of contaminant input from hydrologically upgradient WAGs. While upgradient areas are being remediated, the strategy for WAG 2 is to conduct a long-term monitoring and investigation program that takes full advantage of WAG 2's role as an integrator of contaminant fluxes from other ORNL WAGs and focuses on four key goals: (1) Implement, in concert with other programs, long-term, multimedia environmental monitoring and tracking of contaminants leaving other WAGs, entering WAG 2, and being transported off-site. (2) Provide a conceptual framework to integrate and develop information at the watershed-level for pathways and processes that are key to contaminant movement, and so support remedial efforts at ORNL. (3) Provide periodic updates of estimates of potential risk (both human health and ecological) associated with contaminants accumulating in and moving through WAG 2 to off-site areas. (4) Support the ORNL Environmental Restoration Program efforts to prioritize, remediate, and verify remedial effectiveness for contaminated sites at ORNL, through long-term monitoring and continually updated risk assessments

  8. Non-invasive Investigation of Free Phase Gas Accumulation in a Northern Peatland Using GPR: Vegetation Effects

    Science.gov (United States)

    Parsekian, A.; Nolan, J.; Comas, X.; Slater, L.

    2008-05-01

    Northern peatlands are known to produce methane, although the contribution of this source to the atmospheric methane burden is still uncertain. Biogenic methane releases have become an increasingly important issue with regard to assessing the impact of northern peatlands impact on the global carbon budget. Previous workers have suggested that methane production is pronounced in a zone a few meters below the surface and that accumulation of free phase gas is encouraged by the presence of confining layers that act to hinder FPG release. We used ground penetrating radar (GPR) to non-invasively investigate (1) where free-phase gas (FPG) methane may be accumulating vertically within the peat column of a northern peatland, and (2) the dependence of methane production on vegetation type. Common mid-point (CMP) measurements were applied to investigate the likely vertical spatial distribution/ concentration of trapped methane within the peat profile within different vegetation units. The CMP data were modeled using the Complex Refractive Index Model (CRIM) to obtain a one dimensional model of interval layer velocities presumably representing the vertical distribution of gas content. CMP surveys were conducted at several locations in Caribou Bog peatland (Orono, Maine) in order to assess how peat thickness and surface vegetation communities may be impact FPG accumulation in the sub-surface. These locations include an open pool system, a low shrub heath area and a densely forested zone. As well as having variable surface vegetation communities, the total peat thickness is distinctly different at each of these sites. Preliminary results suggest that the CMP models are distinctly different between these sites and suggest a dependence of FPG accumulation on vegetation type.

  9. Investigation of Temperature Fluctuations Caused by Steam-Water Two-Phase Flow in Pressurizer Spray Piping

    Science.gov (United States)

    Miyoshi, Koji; Nakamura, Akira; Takenaka, Nobuyuki; Oumaya, Toru

    In a PWR plant, a steam-water two-phase flow may possibly exist in the pressurizer spray pipe under a normal operating condition since the flow rate of the spray water is not sufficient to fill the horizontal section of the pipe completely. Initiation of high cycle fatigue cracks is suspected to occur under such thermally stratified two phase flow conditions due to cyclic thermal stress fluctuations caused by oscillations of the water surface. Such oscillations cannot be detected by the measurement of temperature on outer surface of the pipe. In order to clarify the flow and thermal conditions in the pressurizer spray pipe and assess their impact on the pipe structure, an experiment was conducted for a steam-water flow at a low flow rate using a mock-up pressurizer spray pipe. The maximum temperature fluctuation of about 0.2 times of the steam-water temperature difference was observed at the inner wall around water surface in the test section. Visualization tests were conducted to investigate the temperature fluctuation phenomena. It was shown that the fluid temperature fluctuations were not caused by the waves on the water surface, but were caused by liquid temperature fluctuations in water layer below the interface. The influence of small amount of non-condensable gas dissolved in the reactor coolant on the liquid temperature fluctuation phenomena was investigated by injecting air into the experimental loop. The air injection attenuated the liquid temperature fluctuations in the water layer since the condensation was suppressed by the non- condensable gas. It is not expected that wall temperature fluctuation in the actual PWR plant may exceed the temperature equivalent to the fatigue limit stress amplitude when it is assumed to be proportional to the steam-water temperature difference.

  10. Phase II RCRA Facility Investigation Report, Tooele Army Depot-North Area, Group A, Suspected Releases SWMUs; Volume 2 - Appendices A-K

    National Research Council Canada - National Science Library

    1997-01-01

    ... field activities were conducted, and descriptions of sample collection, handling, and shipping procedures. The Phase II RFI field activities were conducted without significant deviation from the project work plans prepared for this investigation...

  11. Experimental investigation on single-phase pressure losses in nuclear debris beds: Identification of flow regimes and effective diameter

    Energy Technology Data Exchange (ETDEWEB)

    Clavier, R., E-mail: remi.clavier@irsn.fr [Institut de Radioprotection et de Sûreté Nucléaire (IRSN) – PSN-RES/SEREX/LE2M, Cadarache bât. 327, 13115 St Paul-lez-Durance (France); Chikhi, N., E-mail: nourdine.chikhi@irsn.fr [Institut de Radioprotection et de Sûreté Nucléaire (IRSN) – PSN-RES/SEREX/LE2M, Cadarache bât. 327, 13115 St Paul-lez-Durance (France); Fichot, F. [Institut de Radioprotection et de Sûreté Nucléaire (IRSN) – PSN-RES/SAG/LEPC, Cadarache bât. 700, 13115 St Paul-lez-Durance (France); Quintard, M. [Université de Toulouse – INPT – UPS – Institut de Mécanique des Fluides de Toulouse (IMFT), Allée Camille Soula, F-31400 Toulouse (France); CNRS – IMFT, F-31400 Toulouse (France)

    2015-10-15

    Highlights: • Single-phase pressure drops versus flow rates in particle beds are measured. • Conditions are representative of the reflooding of a nuclear fuel debris bed. • Darcy, weak inertial, strong inertial and weak turbulent regimes are observed. • A Darcy–Forchheimer law is found to be a good approximation in this domain. • A predictive correlation is derived from new experimental data. - Abstract: During a severe nuclear power plant accident, the degradation of the reactor core can lead to the formation of debris beds. The main accident management procedure consists in injecting water inside the reactor vessel. Nevertheless, large uncertainties remain regarding the coolability of such debris beds. Motivated by the reduction of these uncertainties, experiments have been conducted on the CALIDE facility in order to investigate single-phase pressure losses in representative debris beds. In this paper, these results are presented and analyzed in order to identify a simple single-phase flow pressure loss correlation for debris-bed-like particle beds in reflooding conditions, which cover Darcean to Weakly Turbulent flow regimes. The first part of this work is dedicated to study macro-scale pressure losses generated by debris-bed-like particle beds, i.e., high sphericity (>80%) particle beds with relatively small size dispersion (from 1 mm to 10 mm). A Darcy–Forchheimer law, involving the sum of a linear term and a quadratic deviation, with respect to filtration velocity, has been found to be relevant to describe this behavior in Darcy, Strong Inertial and Weak Turbulent regimes. It has also been observed that, in a restricted domain (Re = 15 to Re = 30) between Darcy and Weak Inertial regimes, deviation is better described by a cubic term, which corresponds to the so-called Weak Inertial regime. The second part of this work aims at identifying expressions for coefficients of linear and quadratic terms in Darcy–Forchheimer law, in order to obtain a

  12. Theoretical investigation of Sn-doped Ge{sub 2}Sb{sub 2}Te{sub 5} alloy in crystalline phase

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Janpreet; Tripathi, S. K., E-mail: surya@pu.ac.in [Department of Physics, Center of Advanced Study in Physics, Panjab University, Chandigarh-160014 (India); Singh, Gurinder; Kaura, Aman [University Institute of Engineering and Technology Hoshiarpur-146001 (India)

    2015-06-24

    Ge{sub 2}Sb{sub 2}Te{sub 5} (GST) is technologically important for phase-change random access memory applications. It has been shown that the 2.2 atomic % doping of Sn weakens the Ge–Te bond strength while maintaining the symmetry of stable phase of GST. The influence of Sn doping upon the phase change characteristics of the crystalline GST alloy has been investigated by ab initio calculations. The lattice parameter, average interface distances between two adjacent (111) layers, equilibrium volume, metallic character and electrical resistance has been calculated for the stable phase of GST and Sn-doped GST.

  13. Experimental investigation on the use of water-phase change material storage in conventional solar water heating systems

    Energy Technology Data Exchange (ETDEWEB)

    Al-Hinti, I.; Al-Ghandoor, A.; Maaly, A.; Abu Naqeera, I.; Al-Khateeb, Z.; Al-Sheikh, O. [The Hashemite University, Zarqa 13115 (Jordan)

    2010-08-15

    This paper presents an experimental investigation of the performance of water-phase change material (PCM) storage for use with conventional solar water heating systems. Paraffin wax contained in small cylindrical aluminum containers is used as the PCM. The containers are packed in a commercially available, cylindrical hot water storage tank on two levels. The PCM storage advantage is firstly demonstrated under controlled energy input experiments with the aid of an electrical heater on an isolated storage tank, with and without the PCM containers. It was found that the use of the suggested configuration can result in a 13-14 C advantage in the stored hot water temperature over extended periods of time. The storage performance was also investigated when connected to flat plate collectors in a closed-loop system with conventional natural circulation. Over a test period of 24 h, the stored water temperature remained at least 30 C higher than the ambient temperature. The use of short periods of forced circulation was found to have minimum effect on the performance of the system. Finally, the recovery effect and the storage performance of the PCM was analyzed under open-loop operation patterns, structured to simulate daily use patterns. (author)

  14. An atmospheric pressure high-temperature laminar flow reactor for investigation of combustion and related gas phase reaction systems.

    Science.gov (United States)

    Oßwald, Patrick; Köhler, Markus

    2015-10-01

    A new high-temperature flow reactor experiment utilizing the powerful molecular beam mass spectrometry (MBMS) technique for detailed observation of gas phase kinetics in reacting flows is presented. The reactor design provides a consequent extension of the experimental portfolio of validation experiments for combustion reaction kinetics. Temperatures up to 1800 K are applicable by three individually controlled temperature zones with this atmospheric pressure flow reactor. Detailed speciation data are obtained using the sensitive MBMS technique, providing in situ access to almost all chemical species involved in the combustion process, including highly reactive species such as radicals. Strategies for quantifying the experimental data are presented alongside a careful analysis of the characterization of the experimental boundary conditions to enable precise numeric reproduction of the experimental results. The general capabilities of this new analytical tool for the investigation of reacting flows are demonstrated for a selected range of conditions, fuels, and applications. A detailed dataset for the well-known gaseous fuels, methane and ethylene, is provided and used to verify the experimental approach. Furthermore, application for liquid fuels and fuel components important for technical combustors like gas turbines and engines is demonstrated. Besides the detailed investigation of novel fuels and fuel components, the wide range of operation conditions gives access to extended combustion topics, such as super rich conditions at high temperature important for gasification processes, or the peroxy chemistry governing the low temperature oxidation regime. These demonstrations are accompanied by a first kinetic modeling approach, examining the opportunities for model validation purposes.

  15. Horonobe Underground Research Laboratory project. Synthesis of phase 1 investigation 2001-2005, Volume 'geological disposal research'

    International Nuclear Information System (INIS)

    Fujita, Tomoo; Taniguchi, Naoki; Maekawa, Keisuke; Sawada, Atsushi; Makino, Hitoshi; Sasamoto, Hiroshi; Yoshikawa, Hideki; Shibata, Masahiro; Ota, Kunio; Miyahara, Kaname; Naito, Morimasa; Yui, Mikazu; Matsui, Hiroya; Hama, Katsuhiro; Kunimaru, Takanori; Takeuchi, Ryuji; Tanai, Kenji; Kurikami, Hiroshi; Wakasugi, Keiichiro; Ishii, Eiichi

    2011-03-01

    This report summarizes the progress of research and development on geological disposal during the surface-based investigation phase (2001-2005) in the Horonobe Underground Research Laboratory project, of which aims are to apply the design methods of geological disposal and mass transport analysis to actual geological conditions obtained from the project as an example of actual geological environment. For the first aim, the design methods for the geological disposal facility proposed in 'H12 report (the second progress report)' was reviewed and then improved based on the recent knowledge. The applicability of design for engineered barrier system, backfill of disposal tunnel, underground facility was illustrated. For the second aim, the conceptual structure from site investigation and evaluation to mass transport analysis was developed as a work flow at first. Then following this work flow a series of procedures for mass transport analysis was applied to the actual geological conditions to illustrate the practical workability of the work flow and the applicability of this methodology. Consequently, based on the results, future subjects were derived. (author)

  16. Investigations of the VVER-1000 coolant transient benchmark phase 1 with the coupled code system RELAP5/PARCS

    International Nuclear Information System (INIS)

    Sanchez-Espinoza, Victor Hugo

    2008-07-01

    As part of the reactor dynamics activities of FZK/IRS, the qualification of best-estimate coupled code systems for reactor safety evaluations is a key step toward improving their prediction capability and acceptability. The VVER-1000 Coolant Transient Benchmark Phase 1 represents an excellent opportunity to validate the simulation capability of the coupled code system RELAP5/PACRS regarding both the thermal hydraulic plant response (RELAP5) using measured data obtained during commissioning tests at the Kozloduy nuclear power plant unit 6 and the neutron kinetics models of PARCS for hexagonal geometries. The Phase 1 is devoted to the analysis of the switching on of one main coolant pump while the other three pumps are in operation. It includes the following exercises: (a) investigation of the integral plant response using a best-estimate thermal hydraulic system code with a point kinetics model (b) analysis of the core response for given initial and transient thermal hydraulic boundary conditions using a coupled code system with 3D-neutron kinetics model and (c) investigation of the integral plant response using a best-estimate coupled code system with 3D-neutron kinetics. Already before the test, complex flow conditions exist within the RPV e.g. coolant mixing in the upper plenum caused by the reverse flow through the loop-3 with the stopped pump. The test is initiated by switching on the main coolant pump of loop-3 that leads to a reversal of the flow through the respective piping. After about 13 s the mass flow rate through this loop reaches values comparable with the one of the other loops. During this time period, the increased primary coolant flow causes a reduction of the core averaged coolant temperature and thus an increase of the core power. Later on, the power stabilizes at a level higher than the initial power. In this analysis, special attention is paid on the prediction of the spatial asymmetrical core cooling during the test and its effects on the

  17. Investigations of the VVER-1000 coolant transient benchmark phase 1 with the coupled code system RELAP5/PARCS

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez-Espinoza, Victor Hugo

    2008-07-15

    As part of the reactor dynamics activities of FZK/IRS, the qualification of best-estimate coupled code systems for reactor safety evaluations is a key step toward improving their prediction capability and acceptability. The VVER-1000 Coolant Transient Benchmark Phase 1 represents an excellent opportunity to validate the simulation capability of the coupled code system RELAP5/PACRS regarding both the thermal hydraulic plant response (RELAP5) using measured data obtained during commissioning tests at the Kozloduy nuclear power plant unit 6 and the neutron kinetics models of PARCS for hexagonal geometries. The Phase 1 is devoted to the analysis of the switching on of one main coolant pump while the other three pumps are in operation. It includes the following exercises: (a) investigation of the integral plant response using a best-estimate thermal hydraulic system code with a point kinetics model (b) analysis of the core response for given initial and transient thermal hydraulic boundary conditions using a coupled code system with 3D-neutron kinetics model and (c) investigation of the integral plant response using a best-estimate coupled code system with 3D-neutron kinetics. Already before the test, complex flow conditions exist within the RPV e.g. coolant mixing in the upper plenum caused by the reverse flow through the loop-3 with the stopped pump. The test is initiated by switching on the main coolant pump of loop-3 that leads to a reversal of the flow through the respective piping. After about 13 s the mass flow rate through this loop reaches values comparable with the one of the other loops. During this time period, the increased primary coolant flow causes a reduction of the core averaged coolant temperature and thus an increase of the core power. Later on, the power stabilizes at a level higher than the initial power. In this analysis, special attention is paid on the prediction of the spatial asymmetrical core cooling during the test and its effects on the

  18. Investigation using X-ray diffraction into the formation of the γ' phase in U-Mo alloys

    International Nuclear Information System (INIS)

    Donze, G.; Cabane, G.

    1959-01-01

    The decomposition of the γ phase of uranium-molybdenum alloys does not take place in the classical manner: the equilibrium products are not formed immediately after the start of the decomposition. The α phase is first precipitated and this liberates molybdenum which enriches the γ phase. When this γ phase is sufficiently enriched, it arranges itself so that the equilibrium product γ' appears. (author) [fr

  19. Investigation of the phase equilibria and phase transformations associated with the Bi2Sr2CaCu2Oy superconductor

    International Nuclear Information System (INIS)

    Holesinger, T.

    1993-01-01

    The solid solution region and reaction kinetics of the Bi 2 Sr 2 CaCu 2 O y (2212) superconductor were examined as a function of temperature and oxygen partial pressure. Crystallization studies from the glassy and molten states were undertaken to determine the phase transformation and kinetics associated with the formation of 2212 and other competing phases. Crystallization of nominal 2212 glasses was found to proceed in two steps with the formation of Bi 2 Sr 2-x Ca x CuO y (2201) and Cu 2 O followed by Bi 2 Sr 3-x Ca x O y , CaO, and SrO. The 2212 phase converts from the 2201 phase with increasing temperatures. However, its formation below 800 C was kinetically limited. At 800 C and above, a nearly full conversion to the 2212 phase was achieved after only one minute although considerably longer anneal times were necessary for the system to reach equilibrium. In low oxygen partial pressures, the solidus is reduced to approximately 750 C. Solidification studies revealed an eutectic structure separating the incongruently melting 2212/2201 phases at high oxygen partial pressures from the congruently melting Bi 2 Sr 3-x Ca x O y (23x) and Bi 2 Sr 2-x Ca x O y (22x) phases present at low oxygen partial pressures. During solidification in various oxygen partial pressures, the separation of CaO in the melt and the initial crystallization of alkaline-earth cuprates leaves behind a Bi-rich liquid from which it is impossible to form single-phase 2212. Hence, significant amounts of 2201 were also present in these samples. These problems could be reduced by melt processing in inert atmospheres. Bulk 2212 material produced in this manner was found to possess high transition temperatures, high intergranular critical current densities below 20K, and modest critical current densities at 77K

  20. Numerical investigation of interfacial mass transport resistance and two-phase flow in PEM fuel cell air channels

    Science.gov (United States)

    Koz, Mustafa

    Proton exchange membrane fuel cells (PEMFCs) are efficient and environmentally friendly electrochemical engines. The performance of a PEMFC is adversely affected by oxygen (O2) concentration loss from the air flow channel to the cathode catalyst layer (CL). Oxygen transport resistance at the gas diffusion layer (GDL) and air channel interface is a non-negligible component of the O2 concentration loss. Simplified PEMFC performance models in the available literature incorporate the O2 resistance at the GDL-channel interface as an input parameter. However, this parameter has been taken as a constant so far in the available literature and does not reflect variable PEMFC operating conditions and the effect of two-phase flow in the channels. This study numerically calculates the O2 transport resistance at the GDL-air channel interface and expresses this resistance through the non-dimensional Sherwood number (Sh). Local Sh is investigated in an air channel with multiple droplets and films inside. These water features are represented as solid obstructions and only air flow is simulated. Local variations of Sh in the flow direction are obtained as a function of superficial air velocity, water feature size, and uniform spacing between water features. These variations are expressed with mathematical expressions for the PEMFC performance models to utilize and save computational resources. The resulting mathematical correlations for Sh can be utilized in PEMFC performance models. These models can predict cell performance more accurately with the help of the results of this work. Moreover, PEMFC performance models do not need to use a look-up table since the results were expressed through correlations. Performance models can be kept simplified although their predictions will become more realistic. Since two-phase flow in channels is experienced mostly at lower temperatures, performance optimization at low temperatures can be done easier.

  1. Investigation of physical image characteristics and phenomenon of edge enhancement by phase contrast using equipment typical for mammography

    International Nuclear Information System (INIS)

    Yamazaki, Asumi; Ichikawa, Katsuhiro; Kodera, Yoshie

    2008-01-01

    A technique called phase contrast mammography (PCM) has only recently been applied in clinical examination. In this application, PCM images are acquired at a 1.75x magnification using an x-ray tube for clinical use, and then reduced to the real size of the object by image processing. The images showed enhanced object edges; reportedly, this enhancement occurred because of the refraction of x rays through a cylindrical object. The authors measured the physical image characteristics of PCM to compare the image characteristics of PCM with those of conventional mammography. More specifically, they measured the object-edge-response characteristics and the noise characteristics in the spatial frequency domain. The results revealed that the edge-response characteristics of PCM outperformed those of conventional mammography. In addition, the characteristics changed with the object-placement conditions and the object shapes. The noise characteristics of PCM were better than those of conventional mammography. Subsequently, to verify why object edges were enhanced in PCM images, the authors simulated image profiles that would be obtained if the x rays were refracted and totally reflected by using not only a cylindrical substance but also a planar substance as the object. So, they confirmed that the object edges in PCM images were enhanced because x rays were refracted irrespective of the object shapes. Further, they found that the edge enhancements depended on the object shapes and positions. It was also proposed that the larger magnification than 1.75 in the commercialized system might be more suitable for PCM. Finally, the authors investigated phase-contrast effects to breast tissues by the simulation and demonstrated that PCM would be helpful in the diagnoses of mammography.

  2. Investigation of grid-enhanced two-phase convective heat transfer in the dispersed flow film boiling regime

    International Nuclear Information System (INIS)

    Miller, D.J.; Cheung, F.B.; Bajorek, S.M.

    2013-01-01

    Highlights: • Experiments were done in the RBHT facility to study the droplet flow in rod bundle. • The presence of a droplet field was found to greatly enhance heat transfer. • A second-stage augmentation was observed downstream of a spacer grid. • This augmentation is due to the breakup of liquid ligaments downstream of the grid. - Abstract: A two-phase dispersed droplet flow investigation of the grid-enhanced heat transfer augmentation has been done using steam cooling with droplet injection experimental data obtained from the Penn State/NRC Rod Bundle Heat Transfer (RBHT) facility. The RBHT facility is a vertical, full length, 7 × 7-rod bundle heat transfer facility having 45 electrically heated fuel rod simulators of 9.5 mm (0.374-in.) diameter on a 12.6 mm (0.496-in.) pitch which simulates a portion of a PWR fuel assembly. The facility operates at low pressure, up to 4 bars (60 psia) and has over 500 channels of instrumentation including heater rod thermocouples, spacer grid thermocouples, closely-spaced differential pressure cells along the test section, several fluid temperature measurements within the rod bundle flow area, inlet and exit flows, absolute pressure, and the bundle power. A series of carefully controlled and well instrumented steam cooling with droplet injection experiments were performed over a range of Reynolds numbers and droplet injection flow rates. The experimental results were analyzed to obtain the axial variation of the local heat transfer coefficients along the rod bundle. At the spacer grid location, the flow was found to be substantially disrupted, with the hydrodynamic and thermal boundary layers undergoing redevelopment. Owing to this flow restructuring, the heat transfer downstream of a grid spacer was found to be augmented above the fully developed flow heat transfer as a result of flow disruption induced by the grid. Furthermore, the presence of a droplet field further enhanced the heat transfer as compared to single

  3. Investigation of the effect of aluminum on the phase composition of Ti-Al-Nb-Mo gamma alloys

    Science.gov (United States)

    Terlikbaeva, A. Zh.; Alimzhanova, A. M.; Shayakhmetova, R. A.; Smagulov, D. U.; Osipov, P. A.

    2017-11-01

    A quantitative analysis of the influence of aluminum concentration on the phase composition of TNM-type Ti-Al-Nb-Mo γ-alloys has been carried out using the Thermo-Calc software and experimental methods. Isothermal and polythermal sections of the corresponding phase diagram have been calculated; the critical temperatures of phase transformations in the alloys of the system, and the chemical compositions of phases formed in them (β, α, α2, γ) have been determined. The influence of the annealing temperature on the microstructure and phase composition of the alloys containing 43 and 40% Al has been studied.

  4. Experiences and needs of parents of critically injured children during the acute hospital phase: A qualitative investigation.

    Science.gov (United States)

    Foster, Kim; Young, Alexandra; Mitchell, Rebecca; Van, Connie; Curtis, Kate

    2017-01-01

    Physical injury is a leading cause of death and disability among children worldwide and the largest cause of paediatric hospital admission. Parents of critically injured children are at increased risk of developing mental and emotional distress in the aftermath of child injury. In the Australian context, there is limited evidence on parent experiences of child injury and hospitalisation, and minimal understanding of their support needs. The aim of this investigation was to explore parents' experiences of having a critically injured child during the acute hospitalisation phase of injury, and to determine their support needs during this time. This multi-centre study forms part of a larger longitudinal mixed methods study investigating the experiences, unmet needs and well-being of parents of critically injured children over the two-year period following injury. This paper describes parents' experiences of having a child 0-13 years hospitalised with critical injury in one of four Australian paediatric hospitals. Semi-structured interviews were conducted with forty parents and transcribed verbatim. The data were managed using NVIVO 10 software and thematically analysed. Forty parents (26 mothers and 14 fathers) of 30 children (14 girls and 16 boys aged 1-13 years) from three Australian States participated. The majority of children were Australian born. Three main themes with sub-themes were identified: navigating the crisis of child injury; coming to terms with the complexity of child injury; and finding ways to meet the family's needs. There is a need for targeted psychological care provision for parents of critically injured children in the acute hospital phase, including psychological first aid and addressing parental blame attribution. Parents and children would benefit from the implementation of anticipatory guidance frameworks informed by a family-centred social ecological approach to prepare them for the trauma journey and for discharge. This approach could

  5. Gas-phase complexes formed between amidoxime ligands and vanadium or iron investigated using electrospray ionization mass spectrometry.

    Science.gov (United States)

    Mustapha, Adetayo M; Pasilis, Sofie P

    2016-08-15

    Amidoxime-functionalized sorbents can be used to extract uranium from seawater. Iron(III) and vanadium(V) may compete with uranium for adsorption sites. We use 2,6-dihydroxyiminopiperidine (DHIP) and N(1) ,N(5) -dihydroxypentanediimidamide (DHPD) to model amidoxime functional groups and characterize the vanadium(V) and iron(III) complexes with these ligands. We also examine the effect of iron(III) and vanadium(V) on uranyl(VI) complexation by DHIP and DHPD. The experiments were carried out in positive ion mode using a quadrupole ion trap mass spectrometer equipped with an electrospray ionization source. The effect on the mass spectra of changes in ligand, metal:ligand mole ratio, and pH was examined. Iron(III) formed a 1:2 metal:ligand complex with DHIP at all metal:ligand mole ratios and pH values investigated; it formed both 1:2 and 1:3 metal:ligand complexes with DHPD. Vanadium(V) formed 1:1 and 1:2 metal:ligand complexes with DHIP. A 1:2 metal:ligand complex was formed with DHPD at all vanadium(V):DHPD mole ratios investigated. Changes in solution pH did not affect the ions observed. The relative binding affinities of the metal ions towards DHIP followed the order iron(III) > vanadium(V) > uranyl(VI). This study presents a first look at the gas-phase vanadium(V)- and iron(III)-DHIP and -DHPD complexes using electrospray ionization mass spectrometry. These metals form stronger complexes with amidoxime ligands than uranyl(VI), and will affect uranyl(VI) adsorption to amidoxime-based sorbents. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  6. Headspace versus direct immersion solid phase microextraction in complex matrixes: investigation of analyte behavior in multicomponent mixtures.

    Science.gov (United States)

    Gionfriddo, Emanuela; Souza-Silva, Érica A; Pawliszyn, Janusz

    2015-08-18

    This work aims to investigate the behavior of analytes in complex mixtures and matrixes with the use of solid-phase microextraction (SPME). Various factors that influence analyte uptake such as coating chemistry, extraction mode, the physicochemical properties of analytes, and matrix complexity were considered. At first, an aqueous system containing analytes bearing different hydrophobicities, molecular weights, and chemical functionalities was investigated by using commercially available liquid and solid porous coatings. The differences in the mass transfer mechanisms resulted in a more pronounced occurrence of coating saturation in headspace mode. Contrariwise, direct immersion extraction minimizes the occurrence of artifacts related to coating saturation and provides enhanced extraction of polar compounds. In addition, matrix-compatible PDMS-modified solid coatings, characterized by a new morphology that avoids coating fouling, were compared to their nonmodified analogues. The obtained results indicate that PDMS-modified coatings reduce artifacts associated with coating saturation, even in headspace mode. This factor, coupled to their matrix compatibility, make the use of direct SPME very practical as a quantification approach and the best choice for metabolomics studies where wide coverage is intended. To further understand the influence on analyte uptake on a system where additional interactions occur due to matrix components, ex vivo and in vivo sampling conditions were simulated using a starch matrix model, with the aim of mimicking plant-derived materials. Our results corroborate the fact that matrix handling can affect analyte/matrix equilibria, with consequent release of high concentrations of previously bound hydrophobic compounds, potentially leading to coating saturation. Direct immersion SPME limited the occurrence of the artifacts, which confirms the suitability of SPME for in vivo applications. These findings shed light into the implementation of in

  7. Applying the Taguchi Method for Investigating the Phase-Locked Loop Dynamics Affected by Hybrid Storage System Parameters

    Directory of Open Access Journals (Sweden)

    Mostafa Ahmadzadeh

    2018-01-01

    Full Text Available Storage systems play an important role in performance of micro-grids. Storage systems may decrease fluctuations caused by periodic and unpredictable nature of distributed generation resource. Some micro-grids are connected to the network via a grid-interface converter. The phase-locked loop (PLL is a commonly technique for the grid synchronization of network-connected converters. Various parameters affect the stability of PLL (including the network-side and microgrid-side parameters. The effect of the micro-grid-side parameters on the stability of the PLL has not been studied so far. In this paper, the stability of PLL influenced by microgrid-side parameters has been evaluated after a detailed analytical modeling of micro-grid components (including the production power fluctuations, energy storage system, microgrid-side loads, controller parameters etc.. This paper proposes two new stability analysis criteria for PLL affected by micro-grid and hybrid storage system parameters. Using proposed criteria for stability of PLL, optimized rate of micro-grid and hybrid storage system parameters are obtained using statistical methods (Taguchi approach. Finally, behavior of PLL affected by hybrid storage system is investigated. The simulation results and eigenvalues analysis confirm the theoretical analysis and proposed criteria.

  8. Quantitative investigation of free radicals in bio-oil and their potential role in condensed-phase polymerization.

    Science.gov (United States)

    Kim, Kwang Ho; Bai, Xianglan; Cady, Sarah; Gable, Preston; Brown, Robert C

    2015-03-01

    We report on the quantitative analysis of free radicals in bio-oils produced from pyrolysis of cellulose, organosolv lignin, and corn stover by EPR spectroscopy. Also, we investigated their potential role in condensed-phase polymerization. Bio-oils produced from lignin and cellulose show clear evidence of homolytic cleavage reactions during pyrolysis that produce free radicals. The concentration of free radicals in lignin bio-oil was 7.5×10(20)  spin g(-1), which was 375 and 138 times higher than free-radical concentrations in bio-oil from cellulose and corn stover. Pyrolytic lignin had the highest concentration in free radicals, which could be a combination of carbon-centered (benzyl radicals) and oxygen-centered (phenoxy radicals) organic species because they are delocalized in a π system. Free-radical concentrations did not change during accelerated aging tests despite increases in molecular weight of bio-oils, suggesting that free radicals in condensed bio-oils are stable. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Investigation of the gas-phase hydrogen/deuterium exchange behavior of aromatic dicarboxylic acids in a quadrupole ion trap

    Science.gov (United States)

    Chipuk, Joseph E.; Brodbelt, Jennifer S.

    2007-11-01

    Gas-phase hydrogen/deuterium (H/D) exchange reactions of four deprotonated aromatic dicarboxylic acids (phthalic acid, isophthalic acid, terephthalic acid and 2,6-naphthalic acid) with D2O were performed in a quadrupole ion trap mass spectrometer. Experimental results showed significant differences in the rate and extent of exchange when the relative position of the carboxylic acid groups varied. Spontaneous and near complete exchange of one aromatic hydrogen atom occurred when the carboxylic acid groups were in the meta-position, whereas no additional exchange was observed for either the ortho- or para-isomers or for the structurally similar naphthalic acid. Computational investigations support the participation of several possible exchange mechanisms with the contribution of each relying heavily on the relative orientation of the acid moieties. A relay mechanism that bridges the deprotonation site and the labile hydrogen site appears to be responsible for the H/D exchange of not only the labile hydrogen atom of isophthalic acid, but also for the formation of a stable carbanion and corresponding subsequent exchange of one aromatic hydrogen atom. The impact of hydrogen bonding on the relay mechanism is demonstrated by the reaction of phthalic acid as the extent and rate of reaction are greatly retarded by the favorable interaction of the two carboxylic acid groups. Finally, a flip-flop mechanism is likely responsible for the exchange of both terephthalic acid and 2,6-naphthalic acid where the reactive sites are too remote for exchange via relay.

  10. Enhanced performance and interfacial investigation of mineral-based composite phase change materials for thermal energy storage.

    Science.gov (United States)

    Li, Chuanchang; Fu, Liangjie; Ouyang, Jing; Yang, Huaming

    2013-01-01

    A novel mineral-based composite phase change materials (PCMs) was prepared via vacuum impregnation method assisted with microwave-acid treatment of the graphite (G) and bentonite (B) mixture. Graphite and microwave-acid treated bentonite mixture (GBm) had more loading capacity and higher crystallinity of stearic acid (SA) in the SA/GBm composite. The SA/GBm composite showed an enhanced thermal storage capacity, latent heats for melting and freezing (84.64 and 84.14 J/g) was higher than those of SA/B sample (48.43 and 47.13 J/g, respectively). Addition of graphite was beneficial to the enhancement in thermal conductivity of the SA/GBm composite, which could reach 0.77 W/m K, 31% higher than SA/B and 196% than pure SA. Furthermore, atomic-level interfaces between SA and support surfaces were depicted, and the mechanism of enhanced thermal storage properties was in detail investigated.

  11. Investigation of the behavior of a three phase grid-connected photovoltaic system to control active and reactive power

    Energy Technology Data Exchange (ETDEWEB)

    Tsengenes, Georgios; Adamidis, Georgios [Department of Electrical Engineering and Computer Engineering, Democritus University of Thrace, University Campus Kimmeria, 67100 Xanthi (Greece)

    2011-01-15

    In this paper, a photovoltaic (PV) system, with maximum power point tracking (MPPT), connected to a three phase grid is presented. The connection of photovoltaic system on the grid takes place in one stage using voltage source inverter (VSI). For a better utilization of the photovoltaic system, the control strategy applied is based on p-q theory. According to this strategy during sunlight the system sends active power to the grid and at the same time compensates the reactive power of the load. In case there is no sunlight (during the night for instance), the inverter only compensates the reactive power of the load. In this paper the use of p-q theory to supply the grid with active power and compensate the reactive power of the load is investigated. The advantage of this control strategy is that the photovoltaic system is operated the whole day. Furthermore, the p-q theory uses simple algebraic calculations without demanding the use of PLL to synchronize the inverter with the grid. (author)

  12. Application of the anisotropic phase-field crystal model to investigate the lattice systems of different anisotropic parameters and orientations

    Science.gov (United States)

    Kundin, Julia; Ajmal Choudhary, Muhammad

    2017-07-01

    In this article, we present the recent advances in the development of the anisotropic phase-field crystal (APFC) model. These advances are important in basic researches for multiferroic and thermoelectric materials with anisotropic crystal lattices and in thin-film applications. We start by providing a general description of the model derived in our previous studies based on the crystal symmetry and the microscopic dynamical density functional theory for anisotropic interactions and show that there exist only two possible degrees of freedom for the anisotropic lattices which are described by two independent parameters. New findings concerning the applications of the APFC model for the estimation of the elastic modules of anisotropic systems including sheared and stretched lattices as well as for the investigation of the heterogeneous thin film growth are described. The simulation results demonstrate the strong dependency of the misfit dislocation formation during the film growth on the anisotropy and reveal the asymmetric behavior in the cases of positive and negative misfits. We also present the development of the amplitude representation for the full APFC model of two orientation variants and show the relationship between the wave vectors and the base angles of the anisotropic lattices.

  13. Effect of methanol on the phase-transition properties of glycerol-monopalmitate lipid bilayers investigated using molecular dynamics simulations: in quest of the biphasic effect.

    Science.gov (United States)

    Laner, Monika; Hünenberger, Philippe H

    2015-02-01

    The effect of methanol on the phase and phase-transition properties of a 2×8×8 glycerol-1-monopalmitate bilayer patch is investigated using a series of 239 molecular dynamics simulations on the 180 ns timescale, considering methanol concentrations cM and temperatures T in the ranges 0-12.3M and 302-338 K, respectively. The results in the form of hysteresis-corrected transition temperatures Tm are compatible with the expected features of the biphasic effect, with a reversal concentration crev of about 5.2 M. Below this concentration, the main transition is between the liquid crystal (LC) and gel (GL) phases, and Tm decreases upon increasing cM. Above this concentration, the interdigitated (ID) phase is the stable ordered phase instead, and Tm slightly increases upon increasing T up to about 10 M. The analysis of the structural and dynamical properties also reveals very different sensitivities and responses of the three phases to changes in cM. In particular, the properties of the GL phase are insensitive to cM, whereas those of the LC and ID phases are altered via an increase of the area per lipid. For the LC phase, increasing cM promotes disorder and fluidity. For the ID phase, in contrast, increasing cM up to about 10 M slightly increases the ordering and rigidity. Two side issues are also addressed, concerning: (i) the occurrence tilt-precession motions in the GL and ID phases; (ii) the influence of the pressure coupling scheme employed in the simulations, semi- or fully-anisotropic, on the simulation results. Copyright © 2014 Elsevier Inc. All rights reserved.

  14. Domain Size of Phase-Separated NaxCoO2 as Investigated by X-Ray Microdiffraction

    Directory of Open Access Journals (Sweden)

    Hideharu Niwa

    2017-03-01

    Full Text Available O3-NaCoO 2 is a promising cathode material for sodium ion secondary batteries (SIBs. Na x CoO 2 shows phase separation (PS into the O3 and O ′ 3 phases in the Na concentration range of 0.89 ⩽ x ⩽ 0.99. In order to estimate the domain size (r in the two-phase region, we performed X-ray microdiffraction (XRMD of thin films of Na x CoO 2 at x = 0.97 and ∼1. We found that r (≈400 nm of the O ′ 3 domain is comparable to the particle size d (=331 ± 87 nm in the as-grown O3-NaCoO 2 film. This observation suggests that individual particles of Na x CoO 2 are single phase to minimize the strain at the O3–O ′ 3 phase boundary.

  15. Electrochemical Investigation of the Corrosion of Different Microstructural Phases of X65 Pipeline Steel under Saturated Carbon Dioxide Conditions

    Directory of Open Access Journals (Sweden)

    Yuanfeng Yang

    2015-05-01

    Full Text Available The aim of this research was to investigate the influence of metallurgy on the corrosion behaviour of separate weld zone (WZ and parent plate (PP regions of X65 pipeline steel in a solution of deionised water saturated with CO2, at two different temperatures (55 °C and 80 °C and at initial pH~4.0. In addition, a non-electrochemical immersion experiment was also performed at 80 °C in CO2, on a sample portion of X65 pipeline containing part of a weld section, together with adjacent heat affected zones (HAZ and parent material. Electrochemical impedance spectroscopy (EIS was used to evaluate the corrosion behaviour of the separate weld and parent plate samples. This study seeks to understand the significance of the different microstructures within the different zones of the welded X65 pipe in CO2 environments on corrosion performance; with particular attention given to the formation of surface scales; and their composition/significance. The results obtained from grazing incidence X-ray diffraction (GIXRD measurements suggest that, post immersion, the parent plate substrate is scale free, with only features arising from ferrite (α-Fe and cementite (Fe3C apparent. In contrast, at 80 °C, GIXRD from the weld zone substrate, and weld zone/heat affected zone of the non-electrochemical sample indicates the presence of siderite (FeCO3 and chukanovite (Fe2CO3(OH2 phases. Scanning Electron Microscopy (SEM on this surface confirmed the presence of characteristic discrete cube-shaped crystallites of siderite together with plate-like clusters of chukanovite.

  16. Investigation of dynamic morphological changes of cancer cells during photoimmuno therapy (PIT) by low-coherence quantitative phase microscopy

    Science.gov (United States)

    Ogawa, Mikako; Yamauchi, Toyohiko; Iwai, Hidenao; Magata, Yasuhiro; Choyke, Peter L.; Kobayashi, Hisataka

    2014-03-01

    We have reported a new molecular-targeted cancer phototherapy, photoimmunotherapy (PIT), which killed implanted tumors in mice without side-effects. To understand the mechanism of cell killing with PIT, three-dimentional dynamic low-coherence quantitative phase microscopy (3D LC-QPM), a device developed by Hamamatsu Photonics K.K, was used to detect morphologic changes in cancer cells during PIT. 3T3/HER2 cells were incubated with anti-HER2 trastuzumab-IR700 (10 μg/mL, 0.1 μM as IR700) for 24 hours, then, three-dimensionally imaged with the LC-QPM during the exposure of two different optically filtered lights for excitation of IR700 (500-780 nm) and imaging (780-950 nm). For comparison with traditional PDT, the same experiments were performed with Photofrin (10 and 1 μM). Serial changes in the cell membrane were readily visualized on 3D LC-QPM. 3T3/HER2 cells began to swell rapidly after exposure to 500-780 nm light excitation. The cell volume reached a maximum within 1 min after continuous exposure, and then the cells appeared to burst. This finding suggests that PIT damages the cell membrane by photo-reaction inducing an influx of water into the cell causing swelling and bursting of the cells. Interestingly, even after only 5 seconds of light exposure, the cells demonstrated swelling and bursting albeit more slowly, implying that sufficient cumulative damage occurs on the cell membrane to induce lethal damage to cells even at minimal light exposure. Similar but non-selective membrane damage was shown in PDT-treated cells Photofrin. Thus, PIT induces sufficient damage to the cell membrane within 5 seconds to induce rapid necrotic cell death which can be observed directly with 3D LC-QPM. Further investigation is needed to evaluate the biochemical mechanisms underlying PIT-induced cellular membrane damage.

  17. Project inspection using mobile technology - phase I : an investigation into existing business processes and areas for improvement using mobile technology.

    Science.gov (United States)

    2013-08-01

    As mobile technology becomes widely available and affordable, transportation agencies can use this technology to : streamline operations involved within project inspection. This research, conducted in two phases, identified : opportunities for proces...

  18. Raman Scattering Proof-of-Concept Investigation to Detect Particle Phase in the Propulsion System Lab (PSL) Icing Duct

    Data.gov (United States)

    National Aeronautics and Space Administration — This proposal addresses a proof-of-concept study using Raman Scattering to distinguish both the particle phase and particle temperature in the Propulsion System Lab...

  19. Experimental Investigation of Phase Equilibria in the Ho-Ti-Si Ternary System at 973 K (700 °C)

    Science.gov (United States)

    Han, Feng; Zhan, Yongzhong

    2018-02-01

    Phase equilibrium relations of the Ho-Ti-Si ternary system at 973 K (700 °C) were experimentally researched by means of X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive spectrometer (EDS). The isothermal section of the system at 973 K (700 °C) consists of 14 three-phase regions, 27 two-phase regions, and 14 single-phase regions. The phases Ti5Si3, Ti5Si4, TiSi, TiSi2, Ho5Si3, Ho5Si4, HoSi, αHoSi2-b, and βHoSi2-a are proved to exist at 973 K (700 °C). Previously reported HoTiSi and Ho2Ti3Si4 ternary compounds were confirmed to exist at this temperature. The solubility of Ho in the intermediate phases (i.e., TiSi2, TiSi, Ti5Si4, and Ti5Si3) at the Ti-Si side is extremely small. The maximum solubilities of Ti in HoSi2-b, Ho5Si4, and Ho5Si3 are confirmed to be 8.0, 7.2, and 6.0 at. pct, respectively.

  20. Ab initio density functional theory investigation of the structural, electronic and optical properties of Ca3Sb2 in hexagonal and cubic phases

    International Nuclear Information System (INIS)

    Arghavani Nia, Borhan; Sedighi, Matin; Shahrokhi, Masoud; Moradian, Rostam

    2013-01-01

    A density functional theory study of structural, electronical and optical properties of Ca 3 Sb 2 compound in hexagonal and cubic phases is presented. In the exchange–correlation potential, generalized gradient approximation (PBE-GGA) has been used to calculate lattice parameters, bulk modulus, cohesive energy, dielectric function and energy loss spectra. The electronic band structure of this compound has been calculated using the above two approximations as well as another form of PBE-GGA, proposed by Engle and Vosko (EV-GGA). It is found that the hexagonal phase of Ca 3 Sb 2 has an indirect gap in the Γ→N direction; while in the cubic phase there is a direct-gap at the Γ point in the PBE-GGA and EV-GGA. Effects of applying pressure on the band structure of the system studied and optical properties of these systems were calculated. - Graphical abstract: A density functional theory study of structural, electronic and optical properties of Ca 3 Sb 2 compound in hexagonal and cubic phases is presented. Display Omitted - Highlights: • Physical properties of Ca 3 Sb 2 in hexagonal and cubic phases are investigated. • It is found that the hexagonal phase is an indirect gap semiconductor. • Ca 3 Sb 2 is a direct-gap semiconductor at the Γ point in the cubic phase. • By increasing pressure the semiconducting band gap and anti-symmetry gap are decreased

  1. Source evaluation report phase 2 investigation: Limited field investigation. Final report: United States Air Force Environmental Restoration Program, Eielson Air Force Base, Alaska

    Energy Technology Data Exchange (ETDEWEB)

    1994-10-01

    This report describes the limited field investigation work done to address issues and answer unresolved questions regarding a collection of potential contaminant sources at Eielson Air Force Base (AFB), near Fairbanks, Alaska. These sources were listed in the Eielson AFB Federal Facility Agreement supporting the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) cleanup of the base. The limited field investigation began in 1993 to resolve all remaining technical issues and provide the data and analysis required to evaluate the environmental hazard associated with these sites. The objective of the limited field investigation was to allow the remedial project managers to sort each site into one of three categories: requiring remedial investigation/feasibility study, requiring interim removal action, or requiring no further remedial action.

  2. Detailed Investigation of the Structural, Thermal, and Electronic Properties of Gold Isocyanide Complexes with Mechano-Triggered Single-Crystal-to-Single-Crystal Phase Transitions.

    Science.gov (United States)

    Seki, Tomohiro; Sakurada, Kenta; Muromoto, Mai; Seki, Shu; Ito, Hajime

    2016-02-01

    Mechano-induced phase transitions in organic crystalline materials, which can alter their properties, have received much attention. However, most mechano-responsive molecular crystals exhibit crystal-to-amorphous phase transitions, and the intermolecular interaction patterns in the daughter phase are difficult to characterize. We have investigated phenyl(phenylisocyanide)gold(I) (1) and phenyl(3,5-dimethylphenylisocyanide)gold(I) (2) complexes, which exhibit a mechano-triggered single-crystal-to-single-crystal phase transition. Previous reports of complexes 1 and 2 have focused on the relationships between the crystalline structures and photoluminescence properties; in this work we have focused on other aspects. The face index measurements of complexes 1 and 2 before and after the mechano-induced phase transitions have indicated that they undergo non-epitaxial phase transitions without a rigorous orientational relationship between the mother and daughter phases. Differential scanning calorimetry analyses revealed the phase transition of complex 1 to be enthalpically driven by the formation of new aurophilic interactions. In contrast, the phase transition of complex 2 was found to be entropically driven, with the closure of an empty void in the mother phase. Scanning electron microscopy observation showed that the degree of the charging effect of both complexes 1 and 2 was changed by the phase transitions, which suggests that the formation of the aurophilic interactions affords more effective conductive pathways. Moreover, flash-photolysis time-resolved microwave conductivity measurements revealed that complex 1 increased in conductivity after the phase change, whereas the conductivity of complex 2 decreased. These contrasting results were explained by the different patterns in the aurophilic interactions. Finally, an intriguing disappearing polymorphism of complex 2 has been reported, in which a polymorph form could not be obtained again after some period of time

  3. Theoretical and experimental investigation of a balanced phase-locked loop based clock recovery at a bit rate of 160 Gb/s

    DEFF Research Database (Denmark)

    Zibar, Darko; Oxenløwe, Leif Katsuo; Clausen, Anders

    2003-01-01

    This paper describes a mathematical model of a balanced opto-electronic phase-locked loop (OPLL), which is required to be very fast for some network applications. OPLL is investigated in terms of clock pulse width, loop filter gain and residuals of the balancing DC level. Based on the guidelines ...

  4. Investigation of influence of the wavelength of probing optical emission on the conditions of visualization of the flow's phase structures in the energy-technique elements

    International Nuclear Information System (INIS)

    Volevatyj, A.A.; Tolkach, A.V.; Bykovskij, Yu.M.

    2002-01-01

    Certain problems of objective visualization of two-phases flows in the energy-technique elements at the investigations by means of photo-, cinema- and video-registration are considered. It is shown an advisability of using of the more long-wave illumination of the medium at the high steam-content values in the flow

  5. Experimental investigation of the Ag–Bi–I ternary system and thermodynamic properties of the ternary phases

    International Nuclear Information System (INIS)

    Mashadieva, Leyla F.; Aliev, Ziya S.; Shevelkov, Andrei V.; Babanly, Mahammad B.

    2013-01-01

    Highlights: ► The self-consistent phase diagram of the Ag–Bi–I system is constructed. ► Ag 2 BiI 5 and AgBi 2 I 7 are the only ternary phases of the system. ► Standard thermodynamic functions of formation and the standard entropies of Ag 2 BiI 5 and AgBi 2 I 7 are calculated. - Abstract: The phase equilibriums in the Ag–Bi–I ternary system and thermodynamic properties of the ternary phases were experimentally determined by using DTA and XRD techniques and EMF measurements with the Ag 4 RbI 5 solid electrolyte. According to the obtained experimental results, the polythermal sections of the ternary phase diagram, its isothermal section at 300 K as well as the projection of the liquids surface have been revised. The fields of the primary crystallization and types and coordinates of nonvariant and monovariant equilibriums were determined. The partial molar functions of silver iodide and silver in the alloys as well as the standard thermodynamic functions of formation and the standard entropies of Ag 2 BiI 5 and AgBi 2 I 7 were calculated based on EMF measurements.

  6. Phase 1 RCRA Facility Investigation/Corrective Measures Study Work Plan for Single-Shell Tank (SST) Waste Management Areas

    International Nuclear Information System (INIS)

    MCCARTHY, M.M.

    1999-01-01

    This document is the master work plan for the Resource Conservation and Recovery Act of 1976 (RCRA) Corrective Action Program (RCAP) for single-shell tank (SST) farms at the US. Department of Energy's (DOE'S) Hanford Site. The DOE Office of River Protection (ORP) initiated the RCAP to address the impacts of past and potential future tank waste releases to the environment. This work plan defines RCAP activities for the four SST waste management areas (WMAs) at which releases have contaminated groundwater. Recognizing the potential need for future RCAP activities beyond those specified in this master work plan, DOE has designated the currently planned activities as ''Phase 1.'' If a second phase of activities is needed for the WMAs addressed in Phase 1, or if releases are detected at other SST WMAs, this master work plan will be updated accordingly

  7. Phase 1 RCRA Facility Investigation & Corrective Measures Study Work Plan for Single Shell Tank (SST) Waste Management Areas

    Energy Technology Data Exchange (ETDEWEB)

    MCCARTHY, M.M.

    1999-08-01

    This document is the master work plan for the Resource Conservation and Recovery Act of 1976 (RCRA) Corrective Action Program (RCAP) for single-shell tank (SST) farms at the US. Department of Energy's (DOE'S) Hanford Site. The DOE Office of River Protection (ORP) initiated the RCAP to address the impacts of past and potential future tank waste releases to the environment. This work plan defines RCAP activities for the four SST waste management areas (WMAs) at which releases have contaminated groundwater. Recognizing the potential need for future RCAP activities beyond those specified in this master work plan, DOE has designated the currently planned activities as ''Phase 1.'' If a second phase of activities is needed for the WMAs addressed in Phase 1, or if releases are detected at other SST WMAs, this master work plan will be updated accordingly.

  8. An investigation on steam-water two-phase forced convection boiling heat transfer in helical-coiled tubes

    International Nuclear Information System (INIS)

    Zhou Yunlong; Sun Bin; Chen Tingkuan; Chen Xuejun

    2002-01-01

    Two-phase flow forced convection boiling heat transfer on helical-coiled tubes has been systematically studied. The experiments have been done on high pressure water loop in Xi'an Jiaotong University. The test condition is as follows: system pressures 6.0 to 11 MPa, mass velocity 400 to 1200 kg/(m 2 ·s), helical diameter 1.37 m and helical angles 3.94 degree. Two-phase forced convection heat transfer coefficients are correlated as function of Lockhart-Martinelli parameter. Subcooling water and superheated vapor forced convection heat transfer coefficient are also presented and compared with other literatures

  9. Quality assurance/quality control summary report on phase 2 of the Clinch River remedial investigation at the Oak Ridge Reservation, Oak Ridge, Tennessee

    International Nuclear Information System (INIS)

    Holladay, S.K.; Anderson, H.M.; Benson, S.B.; Bevelhimer, M.S.; Brandt, C.C.; Chavannes, C.M.; Cook, R.B.; Evans, D.A.; Ford, C.J.; Harris, R.A.; Horwedel, B.M.; Jackson, B.L.

    1996-12-01

    Quality assurance (QA) objectives for Phase 2 were that (1) scientific data generated would withstand scientific and legal scrutiny; (2) data would be gathered using appropriate procedures for sample collection, sample handling and security, chain of custody, laboratory analyses, and data reporting; (3) data would be of known precision and accuracy; and (4) data would meet data quality objectives defined in the Phase 2 Sampling and Analysis Plan. A review of the QA systems and quality control (QC) data associated with the Phase 2 investigation is presented to evaluate whether the data were of sufficient quality to satisfy Phase 2 objectives. The data quality indicators of precision, accuracy, representativeness, comparability, completeness, and sensitivity were evaluated to determine any limitations associated with the data. Data were flagged with qualifiers that were associated with appropriate reason codes and documentation relating the qualifiers to the reviewer of the data. These qualifiers were then consolidated into an overall final qualifier to represent the quality of the data to the end user. In summary, reproducible, precise, and accurate measurements consistent with CRRI objectives and the limitations of the sampling and analytical procedures used were obtained for the data collected in support of the Phase 2 Remedial Investigation

  10. Quality assurance/quality control summary report on phase 2 of the Clinch River remedial investigation at the Oak Ridge Reservation, Oak Ridge, Tennessee

    Energy Technology Data Exchange (ETDEWEB)

    Holladay, S.K.; Anderson, H.M.; Benson, S.B.; Bevelhimer, M.S.; Brandt, C.C.; Chavannes, C.M.; Cook, R.B.; Evans, D.A.; Ford, C.J.; Harris, R.A.; Horwedel, B.M.; Jackson, B.L.

    1996-12-01

    Quality assurance (QA) objectives for Phase 2 were that (1) scientific data generated would withstand scientific and legal scrutiny; (2) data would be gathered using appropriate procedures for sample collection, sample handling and security, chain of custody, laboratory analyses, and data reporting; (3) data would be of known precision and accuracy; and (4) data would meet data quality objectives defined in the Phase 2 Sampling and Analysis Plan. A review of the QA systems and quality control (QC) data associated with the Phase 2 investigation is presented to evaluate whether the data were of sufficient quality to satisfy Phase 2 objectives. The data quality indicators of precision, accuracy, representativeness, comparability, completeness, and sensitivity were evaluated to determine any limitations associated with the data. Data were flagged with qualifiers that were associated with appropriate reason codes and documentation relating the qualifiers to the reviewer of the data. These qualifiers were then consolidated into an overall final qualifier to represent the quality of the data to the end user. In summary, reproducible, precise, and accurate measurements consistent with CRRI objectives and the limitations of the sampling and analytical procedures used were obtained for the data collected in support of the Phase 2 Remedial Investigation.

  11. Experimental and numerical investigation of form-stable dodecane/hydrophobic fumed silica composite phase change materials for cold energy storage

    International Nuclear Information System (INIS)

    Chen, Jiajie; Ling, Ziye; Fang, Xiaoming; Zhang, Zhengguo

    2015-01-01

    Highlights: • Form-stable dodecane/fumed silica composite for cold storage is prepared. • A suggesting hypothesis that explains infiltration mechanism is proposed. • The performance of the composite phase change material is investigated. • Numerical simulation of system is carried out and results fit well. - Abstract: A kind of form-stable composite phase change materials used for cold thermal energy storage is prepared by absorbing dodecane into the hydrophobic fumed silica. With relatively suitable pore diameter and hydrophobic groups, hydrophobic fumed silica is beneficial to the penetration and infiltration of dodecane and the leakage problem solving. Scanned by electron micrographs and Fourier transformation infrared, the composite phase change material is characterized to be just physical penetration. Besides, the differential scanning calorimeter and thermo gravimetric analysis reveals the high enthalpy, good thermal stability and cycling performance of this composite phase change material. What’s more, Hot-Disk thermal constants analyzer demonstrates that the composite phase change material has low thermal conductivity which is desired in cold storage application. In the experiment, a cold energy storage system is set up and the results from the experiment show that the system has excellent performance of cold storage by incorporating composite phase change material. Apart from that, the experimental data is found to have a great agreement with the numerical simulation which is carried out by using the commercial computational fluid dynamics software FLUENT.

  12. Experimental Investigation and Thermodynamic Assessment of Phase Equilibria in the PLLA/Dioxane/Water Ternary System for Applications in the Biomedical Field.

    Science.gov (United States)

    Ruggiero, Flavia; Netti, Paolo Antonio; Torino, Enza

    2015-12-01

    Fundamental understanding of thermodynamic of phase separation plays a key role in tuning the desired features of biomedical devices. In particular, phase separation of ternary solution is of remarkable interest in processes to obtain biodegradable and biocompatible architectures applied as artificial devices to repair, replace, or support damaged tissues or organs. In these perspectives, thermally induced phase separation (TIPS) is the most widely used technique to obtained porous morphologies and, in addition, among different ternary systems, polylactic acid (PLLA)/dioxane/water has given promising results and has been largely studied. However, to increase the control of TIPS-based processes and architectures, an investigation of the basic energetic phenomena occurring during phase separation is still required. Here we propose an experimental investigation of the selected ternary system by using isothermal titration calorimetric approach at different solvent/antisolvent ratio and a thermodynamic explanation related to the polymer-solvents interactions in terms of energetic contribution to the phase separation process. Furthermore, relevant information about the phase diagrams and interaction parameters of the studied systems are furnished in terms of liquid-liquid miscibility gap. Indeed, polymer-solvents interactions are responsible for the mechanism of the phase separation process and, therefore, of the final features of the morphologies; the knowledge of such data is fundamental to control processes for the production of membranes, scaffolds and several nanostructures. The behavior of the polymer at different solvent/nonsolvent ratios is discussed in terms of solvation mechanism and a preliminary contribution to the understanding of the role of the hydrogen bonding in the interface phenomena is also reported. It is the first time that thermodynamic data of a ternary system are collected by mean of nano-isothermal titration calorimetry (nano-ITC). Supporting

  13. Radiotracer investigations for tracing catalyst phase in a Fluid Catalytic Cracking Unit (FCCU) in a petroleum refinery

    International Nuclear Information System (INIS)

    Pant, H.J.; Singh, Gursharan; Nair, A.G.C.; Tomar, B.S.

    2006-01-01

    This paper describes characterization, production and application of lanthanum-140 as a radiotracer for evaluation of radial mixing, measurement of mean residence time (MRT) and estimation of degree of axial mixing of catalyst phase in an FCCU in a petroleum refinery

  14. Correlative theoretical and experimental investigation of the formation of AlYB{sub 14} and competing phases

    Energy Technology Data Exchange (ETDEWEB)

    Hunold, Oliver, E-mail: hunold@mch.rwth-aachen.de; Chen, Yen-Ting; Music, Denis; Baben, Moritz to; Achenbach, Jan-Ole; Keuter, Philipp; Schneider, Jochen M. [Materials Chemistry, RWTH Aachen University, Kopernikusstr. 10, D-52074 Aachen (Germany); Persson, Per O. Å. [Department of Physics, Chemistry and Biology (IFM), Linköping University, S-58183 Linköping (Sweden); Primetzhofer, Daniel [Department of Physics and Astronomy, Uppsala University, Lägerhyddsvägen 1, S-75120 Uppsala (Sweden)

    2016-02-28

    The phase formation in the boron-rich section of the Al-Y-B system has been explored by a correlative theoretical and experimental research approach. The structure of coatings deposited via high power pulsed magnetron sputtering from a compound target was studied using elastic recoil detection analysis, electron energy loss spectroscopy spectrum imaging, as well as X-ray and electron diffraction data. The formation of AlYB{sub 14} together with the (Y,Al)B{sub 6} impurity phase, containing 1.8 at. % less B than AlYB{sub 14}, was observed at a growth temperature of 800 °C and hence 600 °C below the bulk synthesis temperature. Based on quantum mechanical calculations, we infer that minute compositional variations within the film may be responsible for the formation of both icosahedrally bonded AlYB{sub 14} and cubic (Y,Al)B{sub 6} phases. These findings are relevant for synthesis attempts of all boron rich icosahedrally bonded compounds with the space group: Imma that form ternary phases at similar compositions.

  15. Tooele Army Depot - South Area Suspected Release Units. RCRA Facility Investigation - Phase 2, for SWMUs 1, 25, and 27

    National Research Council Canada - National Science Library

    Kamp, Susan; Tate, D. J; Zigich, Daniel; Moss, Pamela; Warner, Alan; Leslie, Mark; Bieniulis, Carol

    1995-01-01

    ... Waste Management Units (SWMUs) 1 and 25 and an RFI-Phase I program to determine the presence or absence of contamination at SWMU 37 at Tooele Army Depot South Area (TEAD-S), near Tooele, Utah. SWMUs 1 and 25...

  16. Atomic resolution investigations of phase transformation from TaN to CrTaN in a steel matrix

    DEFF Research Database (Denmark)

    Danielsen, Hilmar Kjartansson; Hald, John

    2012-01-01

    strength of the steel. The Cr content promotes Z-phase precipitation, making MN strengthening of these materials unfeasible, since 12%Cr is necessary for oxidation resistance. The authors have suggested an acceleration of Z-phase precipitation to obtain a fine and stable distribution of CrMN instead of MN...... atoms diffuse from the steel matrix into TaN precipitates and physically transform them into CrTaN. The crystal structure of the precipitates changes from that of a typical MN NaCl type crystal structure to a Z-phase crystal structure with alternating double layers of Cr and TaN. Since there is a large......In development of 12%Cr high temperature steels used for fossil fired power plants, the precipitation of large Z-phase particles, CrMN, has been identified as a major problem since they replace small and finely distributed MN particles. This causes a premature breakdown in the longterm creep...

  17. Numerical investigation of influence on heat transfer characteristics to pneumatically conveyed dense phase flow by selecting models and boundary conditions

    Science.gov (United States)

    Zheng, Y.; Liu, Q.; Li, Y.

    2012-03-01

    Solids moving with a gas stream in a pipeline can be found in many industrial processes, such as power generation, chemical, pharmaceutical, food and commodity transfer processes. A mass flow rate of the solids is important characteristic that is often required to be measured (and controlled) to achieve efficient utilization of energy and raw materials in pneumatic conveying systems. The methods of measuring the mass flow rate of solids in a pneumatic pipeline can be divided into direct and indirect (inferential) measurements. A thermal solids' mass flow-meter, in principle, should ideally provide a direct measurement of solids flow rate, regardless of inhomogeneities in solids' distribution and environmental impacts. One key issue in developing a thermal solids' mass flow-meter is to characterize the heat transfer between the hot pipe wall and the gas-solids dense phase flow. The Eulerian continuum modeling with gas-solid two phases is the most common method for pneumatic transport. To model a gas-solid dense phase flow passing through a heated region, the gas phase is described as a continuous phase and the particles as the second phase. This study aims to describe the heat transfer characteristics between the hot wall and the gas-solids dense phase flow in pneumatic pipelines by modeling a turbulence gas-solid plug passing through the heated region which involves several actual and crucial issues: selections of interphase exchange coefficient, near-wall region functions and different wall surface temperatures. A sensitivity analysis was discussed to identify the influence on the heat transfer characteristics by selecting different interphase exchange coefficient models and different boundary conditions. Simulation results suggest that sensitivity analysis in the choice of models is very significant. The simulation results appear to show that a combination of choosing the Syamlal-O'Brien interphase exchange coefficient model and the standard k-ɛ model along with

  18. Investigation of the effect of sugar stereochemistry on biologically relevant lyotropic phases from branched-chain synthetic glycolipids by small-angle X-ray scattering.

    Science.gov (United States)

    Zahid, N Idayu; Conn, Charlotte E; Brooks, Nicholas J; Ahmad, Noraini; Seddon, John M; Hashim, Rauzah

    2013-12-23

    Synthetic branched-chain glycolipids are suitable as model systems in understanding biological cell membranes, particularly because certain natural lipids possess chain branching. Herein, four branched-chain glycopyranosides, namely, 2-hexyl-decyl-α-D-glucopyranoside (α-Glc-OC10C6), 2-hexyl-decyl-β-D-glucopyranoside (β-Glc-OC10C6), 2-hexyl-decyl-α-D-galactopyranoside (α-Gal-OC10C6), and 2-hexyl-decyl-β-D-galactopyranoside (β-Gal-OC10C6), with a total alkyl chain length of 16 carbon atoms have been synthesized, and their phase behavior has been studied. The partial binary phase diagrams of these nonionic surfactants in water were investigated by optical polarizing microscopy (OPM) and small-angle X-ray scattering (SAXS). The introduction of chain branching in the hydrocarbon chain region is shown to result in the formation of inverse structures such as inverse hexagonal and inverse bicontinuous cubic phases. A comparison of the four compounds showed that they exhibited different polymorphism, especially in the thermotropic state, as a result of contributions from anomeric and epimeric effects according to their stereochemistry. The neat α-Glc-OC10C6 compound exhibited a lamellar (Lα) phase whereas dry α-Gal-OC10C6 formed an inverse bicontinuous cubic Ia3d (QII(G)) phase. Both β-anomers of glucoside and galactoside adopted the inverse hexagonal phase (HII) in the dry state. Generally, in the presence of water, all four glycolipids formed inverse bicontinuous cubic Ia3d (QII(G)) and Pn3m (QII(D)) phases over wide temperature and concentration ranges. The formation of inverse nonlamellar phases by these Guerbet branched-chain glycosides confirms their potential as materials for novel biotechnological applications such as drug delivery and crystallization of membrane proteins.

  19. Experimental and Numerical Investigation of Four- Phase Flow (Water–Gasoline-Air-Solid in a Fluidized Bed Column

    Directory of Open Access Journals (Sweden)

    Riyadh S. Al-Turaihi

    2016-03-01

    Full Text Available In this paper four phase fluidized bed is experimentally built and numerically modeled to study the bed characteristics such as ratio (the static bed height of solid particle / the bed diameter (H/D, air, gasoline , and water superficial velocity. The test pipe for the experimental rig is Perspex pipe with 1 m long and 0.0254 m diameter. The 2D numerical model has been established with Ansys fluent 15.0. Pressure drop equation is found to relate the pressure drop with the bed parameters with deviation of 22%. The Four-phases was represented by air, water, gasoline and solid particle. The results show that the pressure of the bed increases as the ratio H/D increases and air, gasoline , and water superficial velocity increases. As well as the expansion of the bed increases as air, gasoline, and water superficial velocity increases.

  20. X-ray phase microtomography with a single grating for high-throughput investigations of biological tissue.

    Science.gov (United States)

    Zdora, Marie-Christine; Vila-Comamala, Joan; Schulz, Georg; Khimchenko, Anna; Hipp, Alexander; Cook, Andrew C; Dilg, Daniel; David, Christian; Grünzweig, Christian; Rau, Christoph; Thibault, Pierre; Zanette, Irene

    2017-02-01

    The high-throughput 3D visualisation of biological specimens is essential for studying diseases and developmental disorders. It requires imaging methods that deliver high-contrast, high-resolution volumetric information at short sample preparation and acquisition times. Here we show that X-ray phase-contrast tomography using a single grating can provide a powerful alternative to commonly employed techniques, such as high-resolution episcopic microscopy (HREM). We present the phase tomography of a mouse embryo in paraffin obtained with an X-ray single-grating interferometer at I13-2 Beamline at Diamond Light Source and discuss the results in comparison with HREM measurements. The excellent contrast and quantitative density information achieved non-destructively and without staining using a simple, robust setup make X-ray single-grating interferometry an optimum candidate for high-throughput imaging of biological specimens as an alternative for existing methods like HREM.

  1. Growth of a Copper-Gold Alloy Phase by Bulk Copper Electrodeposition on Gold Investigated by In Situ STM

    DEFF Research Database (Denmark)

    Andersen, Jens Enevold Thaulov; Møller, Per

    1995-01-01

    the potential in the double-layer charging region from 500 to -100 mV and back to 500 mV at a sweep rate of 1 mV/s in an acidified copper sulfate electrolyte (0.01M H2SO4, 0.01M CuSO4, and Millipore water). After completion of the first cycle the gold surface had recrystallized and nuclei of an alloy phase were...... in peak potential for the anodic current transient from E = 20 mV to E = -2 mV was observed after completion of four subsequent cycles of copper electrodeposition/dissolution. The shift is suggested to be equal to the change in potential of the working electrode owing to the formation of the alloy phase....

  2. MicroRaman, PXRD, EDS and microscopic investigation of magnesium calcite biomineral phases. The case of sea urchin biominerals

    Science.gov (United States)

    Borzęcka-Prokop, B.; Wesełucha-Birczyńska, A.; Koszowska, E.

    2007-02-01

    This study concerns Mg-calcite characterization (and in particular molecular structure and microstructural studies of mineral phases) of a sea urchin mineralised test and spines. Sea urchins are spiny sea animals (kingdom Animalia, phylum Echinodermata, class Echinoidea). Microscopic observations, SEM, EDS, PXRD and spectroscopic microRaman methods have been applied to characterize the biomineral parts of the sea urchin. The latter technique is very useful in research of biological systems and especially suitable for monitoring differences within biomineral phases exhibiting varieties of morphological forms. Crystalline magnesium calcium carbonate, Mg xCa 1- xCO 3 (magnesian calcite; space group R-3 cH; a = 4.9594(8) Å, c = 16.886(6) Å), has been identified as the predominant biomineral component.

  3. Possible quadrupolar nematic phase in the frustrated spin chain LiCuSbO4: An NMR investigation

    Science.gov (United States)

    Bosiočić, M.; Bert, F.; Dutton, S. E.; Cava, R. J.; Baker, P. J.; Požek, M.; Mendels, P.

    2017-12-01

    The frustrated one-dimensional quantum magnet LiCuSbO4 is a rare realization of the J1-J2 spin chain model with an easily accessible saturation field, formerly estimated at 12 T. Exotic multipolar nematic phases were theoretically predicted in such compounds just below the saturation field, but without unambiguous experimental observation so far. In this paper we present extensive experimental research on the compound in a wide temperature (30 mK to 300 K) and field (0-13.3 T) range by muon spin rotation (μ SR ), 7Li nuclear magnetic resonance (NMR), and magnetic susceptibility (SQUID). μ SR experiments in zero magnetic field demonstrate the absence of long-range 3D ordering down to 30 mK. Together with former heat capacity data [Dutton et al., Phys. Rev. Lett. 108, 187206 (2012), 10.1103/PhysRevLett.108.187206], magnetic susceptibility measurements suggest a short-range-correlated vector chiral phase in the field range 0-4 T. At the intermediate-field values (5-12 T), the system enters a 3D-ordered spin density wave phase with 0.75 μB per copper site at lowest temperatures (125 mK), estimated by NMR. At still higher field, the magnetization is found to be saturated above 13 T where the spin lattice T1-1 relaxation reveals a spin gap estimated at 3.2(2) K. We narrow down the possibility of observing a multipolar nematic phase to the range 12.5-13 T.

  4. SAXS investigation of a cubic to a sponge (L3) phase transition in self-assembled lipid nanocarriers

    Czech Academy of Sciences Publication Activity Database

    Angelov, Borislav; Angelova, A.; Mutafchieva, R.; Lesieur, S.; Vainio, U.; Garamus, V. M.; Jensen, G. V.; Pedersen, J. S.

    2011-01-01

    Roč. 13, č. 8 (2011), s. 3073-3081 ISSN 1463-9076 R&D Projects: GA ČR GA202/09/2078; GA ČR GAP208/10/1600 Institutional research plan: CEZ:AV0Z40500505 Keywords : lipid-water phases * liquid crystals * swelling Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 3.573, year: 2011

  5. Applying the Taguchi Method for Investigating the Phase-Locked Loop Dynamics Affected by Hybrid Storage System Parameters

    OpenAIRE

    Mostafa Ahmadzadeh; Saeedollah Mortazavi; Mohsen Saniei

    2018-01-01

    Storage systems play an important role in performance of micro-grids. Storage systems may decrease fluctuations caused by periodic and unpredictable nature of distributed generation resource. Some micro-grids are connected to the network via a grid-interface converter. The phase-locked loop (PLL) is a commonly technique for the grid synchronization of network-connected converters. Various parameters affect the stability of PLL (including the network-side and microgrid-side parameters). The ef...

  6. A study to investigate viscous coupling effects on the hydraulic conductance of fluid layers in two-phase flow at the pore level.

    Science.gov (United States)

    Shams, Mosayeb; Raeini, Ali Q; Blunt, Martin J; Bijeljic, Branko

    2018-07-15

    This paper examines the role of momentum transfer across fluid-fluid interfaces in two-phase flow. A volume-of-fluid finite-volume numerical method is used to solve the Navier-Stokes equations for two-phase flow at the micro-scale. The model is applied to investigate viscous coupling effects as a function of the viscosity ratio, the wetting phase saturation and the wettability, for different fluid configurations in simple pore geometries. It is shown that viscous coupling effects can be significant for certain pore geometries such as oil layers sandwiched between water in the corner of mixed wettability capillaries. A simple parametric model is then presented to estimate general mobility terms as a function of geometric properties and viscosity ratio. Finally, the model is validated by comparison with the mobilities computed using direct numerical simulation. Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.

  7. Investigation of electronic phase segregation in La0.75Ca0.15Sr0.10MnO3 manganite

    International Nuclear Information System (INIS)

    Venkatesh, R; Venkateshwarlu, D; Pryds, Nini

    2014-01-01

    The effect of electronic phase segregation in a broad metal-Insulator transition (MIT) observed in La 0.75 Ca 0.25-x Sr x MnO 3 (x=0.1) composition is investigated using heat capacity, magnetization, electrical resistivity and magnetoresistance measurements. The negative magnetoresistance of 65% in an applied magnetic field of 12 T and 15% in 1 T with a broad working range of 18 K around 300 K which is beneficial for room temperature colossal magnetoresistance (CMR) applications. The broad transition in temperature dependent zero field resistivity measurement is analyzed in the light of percolation model indicates the abundance of insulating/metallic clusters in metallic/insulating region. A significant difference between the metallic fraction around the MIT and the ferromagnetic phases observed around the Curie temperature demonstrates the interplay between volume of itinerant and polaronic electronic phases.

  8. Comparison of EMG during passive stretching and shortening phases of each muscle for the investigation of parkinsonian rigidity.

    Science.gov (United States)

    Kwon, Yuri; Kim, Ji-Won; Kim, Ji-Sun; Koh, Seong-Beom; Eom, Gwang-Moon; Lim, Tae-Hong

    2015-01-01

    The aim of this study was to test the hypothesis in the literature that torque resistance of parkinsonian rigidity is the difference between the independent contributions of stretched and shortened muscles. The hypothesis was tested using muscle-specific stretch-shortening (MSSS) EMG ratio in this study. Nineteen patients with idiopathic Parkinson's disease (PD) and 18 healthy subjects (the mean age comparable to that of patients) participated in this study. The EMG activity was measured in the four muscles involved in wrist joint movement, i.e. flexor carpi radialis, flexor carpi ulnaris, extensor carpi radialis and extensor carpi ulnaris. The passive flexion-extension movement with a range of ±30∘ was applied at wrist joint. Root mean squared (RMS) mean was calculated from the envelope of the EMG for each of stretching and shortening phases. MSSS EMG ratio was defined as the ratio of RMS EMG of stretching phase and RMS EMG of shortening phase of a single muscle, and it was calculated for each muscle. MSSS EMG ratios were smaller than one in all muscles. These results indicate that all wrist muscles generate greater mean EMG during shortening than during stretching. Therefore, the torque resistance of parkinsonian rigidity cannot be explained as the simple summation of independent antagonistic torque pair.

  9. Ab initio investigation of B16(GeS), B27(FeB) and B33(CrB/TlI) phases of lead chalcogenides

    International Nuclear Information System (INIS)

    Demiray, Ferhat; Berber, Savas

    2013-01-01

    We report an ab initio investigation of the intermediate phases occurring in the pressure-induced B1–B2 phase transitions of lead chalcogenides PbX (X = S, Se and Te). The equilibrium lattice constants and atomic positions were calculated without symmetry constraints. The total energies of the optimized structures under pressure were obtained to determine the structures of possible intermediate phases and transitions between these structures. PbTe prefers to be in the B27 structure in the whole transition pressure range while the intermediate phase of PbSe is B27 at lower pressures and becomes B16/B33 at ≈5 GPa. Our results help in understanding the difficulties in experimental investigations of the intermediate phase of PbSe. The intermediate phase of PbS is in the B27 structure at lower pressure values, but it should be in the B16/B33 structure with a transition around ≈6 GPa. Our finding that it is possible to find the intermediate structures of PbS and PbSe in B27 and B16/B33 while PbTe adopts only B27 as the intermediate structure is in good agreement with previous research. The electronic structures of the three structures remain semi-conducting in their calculated optimized structures and the fundamental electronic energy gap decreases with increasing pressure. The projected density of states indicates that the bonding between the Pb atom and the chalcogen has both covalent and ionic contributions with a charge transfer from the Pb atom to the chalcogen. (paper)

  10. Contributions of gas-phase plasma chemistry to surface modifications and gas-surface interactions: investigations of fluorocarbon rf plasmas

    Science.gov (United States)

    Cuddy, Michael F., II

    The fundamental aspects of inductively coupled fluorocarbon (FC) plasma chemistry were examined, with special emphasis on the contributions of gas-phase species to surface modifications. Characterization of the gas-phase constituents of single-source CF4-, C2F6-, C3F 8-, and C3F6-based plasmas was performed using spectroscopic and mass spectrometric techniques. The effects of varying plasma parameters, including applied rf power (P) and system pressure (p) were examined. Optical emission spectroscopy (OES) and laser-induced fluorescence (LIF) spectroscopy were employed to monitor the behavior of excited and ground CFx (x = 1,2) radicals, respectively. Mass spectrometric techniques, including ion energy analyses, elucidated behaviors of nascent ions in the FC plasmas. These gas-phase data were correlated with the net effect of substrate processing for Si and ZrO2 surfaces. Surface-specific analyses were performed for post-processed substrates via x-ray photoelectron spectroscopy (XPS) and contact angle goniometry. Generally, precursors with lower F/C ratios tended to deposit robust FC films of high surface energy. Precursors of higher F/C ratio, such as CF4, were associated with etching or removal of material from surfaces. Nonetheless, a net balance between deposition of FC moieties and etching of material exists for each plasma system. The imaging of radicals interacting with surfaces (IRIS) technique provided insight into the phenomena occurring at the interface of the plasma gas-phase and substrate of interest. IRIS results demonstrate that CFx radicals scatter copiously, with surface scatter coefficients, S, generally greater than unity under most experimental conditions. Such considerable S values imply surface-mediated production of the CFx radicals at FC-passivated sites. It is inferred that the primary route to surface production of CFx arises from energetic ion bombardment and ablation of surface FC films. Other factors which may influence the observed CFx

  11. Ab initio density functional theory investigation of the structural, electronic and optical properties of Ca{sub 3}Sb{sub 2} in hexagonal and cubic phases

    Energy Technology Data Exchange (ETDEWEB)

    Arghavani Nia, Borhan, E-mail: b.arghavani@gmail.com [Department of Physics, Kermanshah Branch, Islamic Azad University, Kermanshah (Iran, Islamic Republic of); Sedighi, Matin [Department of Physics, Kermanshah Branch, Islamic Azad University, Kermanshah (Iran, Islamic Republic of); Shahrokhi, Masoud [Young Researchers and Elite Club, Kermanshah Branch, Islamic Azad University, Kermanshah (Iran, Islamic Republic of); Moradian, Rostam [Nano-Science and Nano-Technology Research Center, Razi University, Kermanshah (Iran, Islamic Republic of); Computational Physics Science Research Laboratory, Department of Nano-Science, Institute for Studies in Theoretical Physics and Mathematics (IPM), P.O. Box 19395-1795, Tehran (Iran, Islamic Republic of)

    2013-11-15

    A density functional theory study of structural, electronical and optical properties of Ca{sub 3}Sb{sub 2} compound in hexagonal and cubic phases is presented. In the exchange–correlation potential, generalized gradient approximation (PBE-GGA) has been used to calculate lattice parameters, bulk modulus, cohesive energy, dielectric function and energy loss spectra. The electronic band structure of this compound has been calculated using the above two approximations as well as another form of PBE-GGA, proposed by Engle and Vosko (EV-GGA). It is found that the hexagonal phase of Ca{sub 3}Sb{sub 2} has an indirect gap in the Γ→N direction; while in the cubic phase there is a direct-gap at the Γ point in the PBE-GGA and EV-GGA. Effects of applying pressure on the band structure of the system studied and optical properties of these systems were calculated. - Graphical abstract: A density functional theory study of structural, electronic and optical properties of Ca{sub 3}Sb{sub 2} compound in hexagonal and cubic phases is presented. Display Omitted - Highlights: • Physical properties of Ca{sub 3}Sb{sub 2} in hexagonal and cubic phases are investigated. • It is found that the hexagonal phase is an indirect gap semiconductor. • Ca{sub 3}Sb{sub 2} is a direct-gap semiconductor at the Γ point in the cubic phase. • By increasing pressure the semiconducting band gap and anti-symmetry gap are decreased.

  12. Investigation of the retention/pH profile of zwitterionic fluoroquinolones in reversed-phase and ion-interaction high performance liquid chromatography.

    Science.gov (United States)

    Pistos, C; Tsantili-Kakoulidou, A; Koupparis, M

    2005-09-15

    The retention/pH profiles of three fluoroquinolones, ofloxacin, norfloxacin and ciprofloxacin, was investigated by means of reversed-phase high performance liquid chromatography (RP-HPLC) and reversed-phase ion-interaction chromatography (RP-IIC), using an octadecylsilane stationary phase and acetonitrile as organic modifier. Sodium hexanesulphonate and tetrabutylammonium hydroxide were used as sources of counter ions in ion-interaction chromatography. The retention/pH profiles under in RP-HPLC were compared to the corresponding lipophilicity/pH profiles. Despite the rather hydrophilic nature of the three fluoroquinolones positive retention factors were obtained while there was a shift of the retention maximum towards more acidic pH values. This behavior was attributed mainly to non-hydrophobic silanophilic interactions with the silanized silica gel material of the stationary phase. In ion-interaction chromatography the effect of counter ions over a broad pH range was found to be ruled rather by the ion pair formation in the mobile phase which led to a drastic decrease in retention as a consequence of the disruption of the zwitterionic structure and thereupon the deliberation of a net charge in the molecules. At pH values at which zwitterionic structure was not favored both the ion-exchange and ion pair formation mechanisms were assumed to contribute to the retention.

  13. The nitrogen doping effect on the properties of Ge-In-Sb-Te phase-change recording media investigated by blue-light laser

    International Nuclear Information System (INIS)

    Yeh, T.-T.; Hsieh, T.-E.; Shieh, H.-P.D.

    2005-01-01

    This work investigates the thermal, optical and recrystallization properties as well as the microstructure of nitrogen-doped Ge-In-Sb-Te (GIST) phase-change material when irradiated by blue-light laser. The experimental results showed that nitrogen doping at the condition of N 2 /Ar sputtering gas flow ratio equals to 3% might enhance the recrystallization speed of GIST recording layer up to 1.5 times. However, the disk failed when too much nitrogen (N 2 /Ar ≥ 5.0%) was introduced. The data obtained by differential scanning calorimetry, X-ray diffraction and ellipsometry revealed changes of thermal and optical properties due to the nitrogen doping in GIST. When appropriate amount of nitrogen was added, the activation energy (E a ) of amorphous-crystalline phase transition of GIST decreased and the optical constants of amorphous and crystalline phases (except the k value of amorphous phase) gradually reduced with the increase of wavelength in the range of 600-750 nm. Modulation simulation based on the reflectively of doped GIST layers obtained from static test indicated that appropriate nitrogen doping benefited the signal characteristics of optical disks. Transmission electron microscopy observed numerous tiny precipitates uniformly distributed in the doped GIST layers. These were believed to be nitride particles generated by nitrogen doping that might offer the preferential sites for amorphous-crystalline phase transition so that the recrystallization speed was accelerated

  14. Analysis of the cavitating flow induced by an ultrasonic horn – Experimental investigation on the influence of actuation phase, amplitude and geometrical boundary conditions

    Directory of Open Access Journals (Sweden)

    Müller Saskia

    2014-03-01

    Full Text Available Till today, factors influencing the formation and collapse of densely distributed, interacting cavitation bubbles are only qualitatively understood. The aim of the present study is to investigate experimentally the influence of selected boundary conditions on the number and size distribution of cavitation bubbles created by an ultrasonic horn (sonotrode. Cavitation bubble clouds below the sonotrode were recorded by means of phase-locked shadowgraphy imaging. The time integrated number of cavitation bubbles was found to decrease exponentially with growing bubble radius. The number of bubbles was increased with growing actuation amplitude and gap width between the sonotrode tip and an opposing solid wall. Furthermore, it could be shown that the number of cavitation bubbles depends on the actuation phase. Future investigations will focus on establishing a statistical relation between the number and size distribution of cavitation bubbles in the near wall region and the resulting cavitation erosion on solid surfaces.

  15. Investigation of the solubility and the potentials for purification of serum amyloid A (SAA) from equine acute phase serum

    DEFF Research Database (Denmark)

    Christensen, Michelle Brønniche; Sørensen, Jens Christian; Jacobsen, Stine

    2013-01-01

    for purification of equine SAA based on biochemical properties.Freeze dried equine acute phase serum was dissolved in 70% 2-propanol, 8 M urea, and milli-Q water, respectively. Supercritical fluid extraction (SFE), size-exclusive chromatography (FPLC-SEC), and preparative isoelectric focusing (IEF) were performed...... in the attempt to purify. Immunostaining of IEF blots were used for isoform-specific detection of SAA in the preparations and purity was assessed by silverstained SDS-PAGE. FINDINGS: SAA was soluble in 70% 2-propanol, 8 M urea and Milli-Q water. SAA was not separated in the lipophilic or ampipathic fractions...

  16. New investigations on shock-wave synthesized high-pressure phases in the system Si-Al-O-N

    Science.gov (United States)

    Schlothauer, T.; Greif, A.; Keller, K.; Schwarz, M. R.; Kroke, E.; Heide, G.

    2012-12-01

    The shock-wave synthesis of nanostructured high-pressure phases at a gram-scale permits the analysis of spinel type nitrides with different chemical composition using methods not suitable for microgram amounts of material. Methods with a significant mass loss through the analytical process like TG-MS or FT-IR or bulk methods at the g-scale like 29Si-MAS-NMR or neutron diffraction were used. The synthesis of pure high-pressure modifications (gamma-phases) of different SiAlON-compounds using amorphous H-bearing precursors at pressures of 30-40 GPa is a necessary prerequisite for precise determinations of crystal chemical features. Etching with HF is a well-known method to purify the high-pressure nitrides (Sekine 2002). The etched parts were analyzed by neutron diffraction, TG-MS, and carrier gas hot extraction (CGHE). Volatile elements like H2 and Cl2, as well as non-stoichiometric oxygen and nitrogen, and NOx, H2O are enriched in the disordered rims. This degassing process ends at temperatures of approximately 600°C, while the spinel structure remains well preserved up to 1300°C. Under these conditions the gamma-phases stay unchanged under air, argon and vacuum. Furthermore chlorine, an important impurity of the H-bearing precursors neither influences the synthesized products nor the synthesis process itself. IR-spectroscopy of gamma-Si3(O,N)4 shows that peak shifts of octahedral lattice vibrations (≈ 680 cm-1) and both tetrahedral vibrations (ny3 and ny4) (Jeanloz 1980, Preudhomme & Tarte 1971) to higher frequencies with decreasing oxygen content occur. This effect is also visible in samples contaminated with impurities of low pressure modifications. The more complex structure of gamma-SiAlON and the simultaneously exchange of the cation- and the anion-positions prevents the appearance of this important feature. Yet to be synthesized pure gamma-SiAlON using similar H-bearing precursors is necessary to resolve its structure. Sekine, T., H. He, T. Kobayashi, K

  17. Protection Of TEG Module at High Temperature Transient Boundary Condition Using Phase Change Materials, an Experimental Investigation

    DEFF Research Database (Denmark)

    Ahmadi Atouei,, Saeed; Rezaniakolaei, Alireza; Akbar Ranjbar, Ali

    2017-01-01

    phase change materials (PCM) in an aluminium box are placed between heat source and the thermoelectric module. The results show when the input heat flux is high, a fraction of the thermal energy is saved in the PCM during the melting process, and when the heat source is off, the saved energy in the PCM...... release slowly, causing a more stable electrical energy production by the TEM and lower the effect of the heat source temperature fluctuations. This study also shows by design of a proper geometry and selection of efficient PCMs, not only the high temperature pulse by the heat source is damped, also more...

  18. Investigations on microstructure of Chinese traditional medicine using phase-contrast imaging with microfocus X-ray tube

    International Nuclear Information System (INIS)

    Wei Xun; Chinese Academy of Sciences, Beijing; Xiao Tiqiao; Chen Min; Liu Lixiang; Luo Yuyu; Du Guohao; Xu Hongjie

    2005-01-01

    The microscopic morphology of plant cells and their ergastic substances is an important standard for the identification of Chinese traditional medicine. The authors have developed a new method, X-ray phase-contrast imaging (XPCI) based on the microfocus X-ray tube, to explore microstructures of Chinese herbal medicine. The results indicate that XPCI is capable of distinguishing the structures commonly used in the identification. Non-destructive detection and high sensibility are counted among the major advantages of XPCI. The possibility of future applications of XPCI in the field of medicine identification is discussed. (authors)

  19. Study of hematite-iron phase transformation during iron-carbon core-shell nanoparticles synthesis and investigation of their magnetic and microwave properties

    OpenAIRE

    Omid Khani; Morteza Zargar Shoushtari; Mohammad Jazirehpour; Mansoor Farbod

    2017-01-01

    The structural properties and microwave absorption capability of the iron nanoparticles and iron-carbon core-shell nanoparticles have been studied, in the present paper. The investigated nanoparticles were synthesized by hydrothermal route and by reduction of hematite nanoparticles during annealing in argon-hydrogen atmosphere. Hematite-iron phase transformation during the reduction process has been studied by X-ray diffraction (XRD). XRD patterns showed that in iron nanoparticles, hematite-i...

  20. Heat transfer characteristics of thermal energy storage for PCM (phase change material) melting in horizontal tube: Numerical and experimental investigations

    International Nuclear Information System (INIS)

    Aadmi, Moussa; Karkri, Mustapha; El Hammouti, Mimoun

    2015-01-01

    This paper focuses on the experimental and numerical study of the storage and release of thermal heat during melting and solidification of PCM (phase change material). Heat transfer enhancement techniques such as the use of conductors like graphite and metal tubes have been proven to be effective. The material used for thermal energy storage systems is a composite based on epoxy resin loaded with metal hollow tubes filled with paraffin wax. Differential Scanning Calorimetry has been used for measurement of melting enthalpy and determination of heat capacity. The thermophysical properties of the prepared composite phase change material have been characterized using a new transient hot plate apparatus. The results have shown that most important thermal properties of these composites at the solid and liquid states are the ‘‘apparent’’ thermal conductivity, the heat storage capacity and the latent heat of fusion. These experimental results have been simulated using numerical Comsol ® Multiphysics 4.3 based models with success. The results of the experimental investigation are compared favorably with the numerical results and thus serve to validate the numerical approach. - Highlights: • Phase change materials based on cylindrical used as new energy storage system. • Thermophysical properties and the melting process of composites were investigated. • All experimental results have been simulated using Comsol ® Multiphysiques. • The ability to store and release the thermal energy were investigated. • Good improvement in the thermal conductivity of composites

  1. Simultaneous X-ray diffraction and phase-contrast imaging for investigating material deformation mechanisms during high-rate loading

    Energy Technology Data Exchange (ETDEWEB)

    Hudspeth, M. [Purdue University, West Lafayette, IN 47907 (United States); Sun, T. [Argonne National Laboratory, Argonne, IL 60439 (United States); Parab, N.; Guo, Z. [Purdue University, West Lafayette, IN 47907 (United States); Fezzaa, K. [Argonne National Laboratory, Argonne, IL 60439 (United States); Luo, S. [The Peac Institute of Multiscale Sciences, Chengdu, Sichuan 610207, People’s Republic of (China); Chen, W., E-mail: wchen@purdue.edu [Purdue University, West Lafayette, IN 47907 (United States)

    2015-01-01

    A simultaneous X-ray imaging and diffraction technique has been developed for studying dynamic material behaviors during high-rate tensile loading provided by a miniature Kolsky bar. Using a high-speed camera and an intensified charge-coupled device (ICCD), a simultaneous X-ray imaging and diffraction technique has been developed for studying dynamic material behaviors during high-rate tensile loading. A Kolsky tension bar has been used to pull samples at 1000 s{sup −1} and 5000 s{sup −1} strain-rates for super-elastic equiatomic NiTi and 1100-O series aluminium, respectively. By altering the ICCD gating time, temporal resolutions of 100 ps and 3.37 µs have been achieved in capturing the diffraction patterns of interest, thus equating to single-pulse and 22-pulse X-ray exposure. Furthermore, the sample through-thickness deformation process has been simultaneously imaged via phase-contrast imaging. It is also shown that adequate signal-to-noise ratios are achieved for the detected white-beam diffraction patterns, thereby allowing sufficient information to perform quantitative data analysis diffraction via in-house software (WBXRD-GUI). Of current interest is the ability to evaluate crystal d-spacing, texture evolution and material phase transitions, all of which will be established from experiments performed at the aforementioned elevated strain-rates.

  2. Two-phase pressurized thermal shock investigations using a 3D two-fluid modeling of stratified flow with condensation

    International Nuclear Information System (INIS)

    Yao, W.; Coste, P.; Bestion, D.; Boucker, M.

    2003-01-01

    In this paper, a local 3D two-fluid model for a turbulent stratified flow with/without condensation, which can be used to predict two-phase pressurized thermal shock, is presented. A modified turbulent K- model is proposed with turbulence production induced by interfacial friction. A model of interfacial friction based on a interfacial sublayer concept and three interfacial heat transfer models, namely, a model based on the small eddies controlled surface renewal concept (HDM, Hughes and Duffey, 1991), a model based on the asymptotic behavior of the Eddy Viscosity (EVM), and a model based on the Interfacial Sublayer concept (ISM) are implemented into a preliminary version of the NEPTUNE code based on the 3D module of the CATHARE code. As a first step to apply the above models to predict the two-phase thermal shock, the models are evaluated by comparison of calculated profiles with several experiments: a turbulent air-water stratified flow without interfacial heat transfer; a turbulent steam-water stratified flow with condensation; turbulence induced by the impact of a water jet in a water pool. The prediction results agree well with the experimental data. In addition, the comparison of three interfacial heat transfer models shows that EVM and ISM gave better prediction results while HDM highly overestimated the interfacial heat transfers compared to the experimental data of a steam water stratified flow

  3. Investigation of Di-ethylhexyl Phthalate Migration by Applying Magnetic Solid Phase Extraction Method Followed by GC-FID Determination

    Directory of Open Access Journals (Sweden)

    Mohammad Faraji

    2016-10-01

    Full Text Available Background and Objectives: The addition of plasticizers (mainly phthalates and adipates makes plastic flexible and popular for packaging, storing and preserving food, water, and so on. The most widely used plasticizer in food contact applications is di-ethylhexyl phthalate (DEHP though being suspected to have carcinogenic and estrogenic properties. The aim of this study is application of magnetic solid phase extraction as new absorbent for determination of DEHP in water samples by gas chromatography (GC. Materials and Methods: Important factors in extraction, separation and determination processes were optimized using the one-variable-at-a-time method. For optimization, all tests were performed two times. Figures of merit of the proposed method were evaluated. The amount of DEHP in some water samples was determined using the proposed method. Results: The results showed that the obtained chromatogram of extract was free of significant interference. The preservatives’ recoveries ranged from 91.6% to 102.2%. Limit of detection and limit of quantitation were 0.1 mg kg-1 and 0.3 µg L-1, respectively. Concentration of DEHP in the studied samples was in the range of N.D-2.3 µg L-1. Conclusions: The acceptable performance and reliability of the proposed method were demonstrated. Temperature and time were fount as the most effective parameters in migration of DEHP. Keywords: Di-ethylhexyl phthalate, Magnetic solid phase extraction, Migration, Gas chromatography

  4. The pressure induced B1-B2 phase transition of alkaline halides and alkaline earth chalcogenides. A first principles investigation

    International Nuclear Information System (INIS)

    Potzel, Oliver; Taubmann, Gerhard

    2011-01-01

    In this work, we considered the pressure induced B1-B2 phase transition of AB compounds. The DFT calculations were carried out for 11 alkaline halides, 11 alkaline earth chalcogenides and the lanthanide pnictide CeP. For both the B1 and the B2 structures of each compound, the energy was calculated as a function of the cell volume. The transition pressure, the bulk moduli and their pressure derivatives were obtained from the corresponding equations of state. The transition path of the Buerger mechanism was described using roots of the transition matrix. We correlated the computed enthalpies of activation to some structure defining properties of the compounds. A fair correlation to Pearsons hardness of the ions was observed. -- Graphical abstract: Pressure induced transition from the B1 structure (left) via the transition state (middle) to the B2 structure (right). Display Omitted Highlights: → Pressure induced phase transitions in AB compounds were considered. → Alkaline halides and alkaline earth chalcogenides were treated. → DFT calculations with periodic boundary conditions were applied. → The transition path was described by roots of the transition matrix. → The enthalpy of activation was calculated for numerous compounds.

  5. Investigation of microstructural evolution and electrical properties for Ni-Sn transient liquid-phase sintering bonding

    Science.gov (United States)

    Feng, Hong-Liang; Huang, Ji-Hua; Yang, Jian; Zhou, Shao-Kun; Zhang, Rong; Wang, Yue; Chen, Shu-Hai

    2017-11-01

    Ni/Ni-Sn/Ni sandwiched simulated package structures were successfully bonded under low temperature and low pressure by Ni-Sn transient liquid-phase sintering bonding. The results show that, after isothermally holding for 240 min at 300 °C and 180 min at 340 °C, Sn was completely transformed into Ni3Sn4 intermetallic compounds. When the Ni3Sn4 phases around Ni particles were pressed together, the porosity of the bonding layer increased, which obviously differed from the normal sintering densification process. With further analysis of this phenomenon, it was found that large volume shrinkage (14.94% at 340 °C) occurred when Ni reacted with Sn to form Ni3Sn4, which caused void formation. A mechanistic model of the microstructural evolution in the bonding layer was proposed. Meanwhile, the resistivity of the bonding layer was measured and analyzed by using the four-probe method; the microstructural evolution was well reflected by the resistivity of the bonding layer. The relationship between the resistivity and microstructure was also discussed in detail.[Figure not available: see fulltext.

  6. Investigation and modeling of stable phase of crystal in Gd2X(X=Al, Ga, In) IMC